Hypothermia

Hypothermia (from Greek ὑποθερμία) is a condition in which an organism's temperature drops below that required for normal metabolism and body functions. In warm-blooded animals, core body temperature is maintained near a constant level through biologic homeostasis. However, when the body is exposed to cold, its internal mechanisms may be unable to replenish the heat that is being lost to the organism's surroundings.
Hypothermia is the opposite of hyperthermia, the condition that causes heat exhaustion and heat stroke.

Symptoms
Normal body temperature in humans is 36.6–37.0 °C (97.9–98.6 °F). Hypothermia can be divided into three stages of severity.

Stage 1
Body temperature drops by 1–2 °C (1.8–3.6 °F) below normal temperature (35–37 °C or 95–98.6 °F. Mild to strong shivering occurs. The victim is unable to perform complex tasks with the hands; the hands become numb. Blood vessels in the outer extremities constrict, lessening heat loss to the outside air. Breathing becomes quick and shallow. Goose bumps form, raising body hair on end in an attempt to create an insulating layer of air around the body (which is of limited use in humans due to lack of sufficient hair, but useful in other species). Victim may feel sick to their stomach, and very tired. Often, a person will experience a warm sensation, as if they have recovered, but they are in fact heading into Stage 2. Another test to see if the person is entering stage 2 is if they are unable to touch their thumb with their little finger; this is the first stage of muscles not working. They might start to have trouble seeing.

Stage 2
Body temperature drops by 2–4 °C (3.8–7.6 °F) below normal temperature (33–35 °C or 91–94.8 °F). Shivering becomes more violent. Muscle mis-coordination becomes apparent. Movements are slow and labored, accompanied by a stumbling pace and mild confusion, although the victim may appear alert. Surface blood vessels contract further as the body focuses its remaining resources on keeping the vital organs warm. The victim becomes pale. Lips, ears, fingers and toes may become blue.

Stage 3
Body temperature drops below approximately 32 °C (89.6 °F). Shivering usually stops. Difficulty speaking, sluggish thinking, and amnesia start to appear; inability to use hands and stumbling is also usually present. Cellular metabolic processes shut down. Below 30 °C (86.0 °F), the exposed skin becomes blue and puffy, muscle coordination becomes very poor, walking becomes almost impossible, and the victim exhibits incoherent/irrational behavior including terminal burrowing or even a stupor. Pulse and respiration rates decrease significantly, but fast heart rates (ventricular tachycardia, atrial fibrillation) can occur. Major organs fail. Clinical death occurs. Because of decreased cellular activity in stage 3 hypothermia, the body will actually take longer to undergo brain death.

Immersion hypothermia
Hypothermia of both the extremities and body core continues to be a major limitation to diving in cold water. Cooling in the extremities is often the limitation to operations. The limitation of finger dexterity due to pain or numbness decreases general safety and work capacity, which consequently increases the risk of other injuries.
For divers breathing heliox below 100 meters wearing hot water suits, the inspired gas must be heated, or the symptoms of hypothermia can set in without the divers realizing it.
Other predisposing factors leading to immersion hypothermia include dehydration, inadequate rewarming with repetitive operations, starting operations while wearing cold, wet dry suit undergarments, sweating with work, inadequate thermal insulation (for example, thin dry suit undergarment), lack of heated breathing gas with deep heliox diving, and poor physical conditioning.
Moderate and severe cases of hypothermia require immediate hospitalization. In a hospital, external treatments, such as heated blankets are used to warm patients with mild hypothermia, as well as internal treatments such as injected warm fluids. For severe cases of hypothermia, patients may undergo lavage (washing) of the bladder, stomach, chest and abdominal cavities with warmed fluids. These patients are at high risk for arrhythmias (irregular heartbeats), and care must be taken to minimize jostling and other disturbances until they have been sufficiently warmed, as these arrhythmias are very difficult to treat while the victim is still cold.
An important tenet of treatment is that a person cannot be considered dead until he/she has been adequately warmed. Remarkable accounts of recovery after prolonged cardiac arrest have been reported in patients with hypothermia, such as children who have been submerged in cold water for more than 15 minutes (called mini-hibernation). It is presumed that this is because the low temperature prevents some of the cellular damage that occurs when blood flow and oxygen are lost for an extended period of time.

Prevention
Appropriate clothing helps to prevent hypothermia. Wearing cotton in chilly weather is a particular hypothermia risk as it retains water, and water quickly conducts heat away from the body. Even in dry weather, cotton clothing can become damp from perspiration, and chilly after the wearer stops exercising. Synthetic and wool fabrics provide far better insulation when wet and dry more quickly. Some synthetic fabrics are even designed to wick perspiration away from the body, such as liner socks.
Heat loss on land is very difficult to predict due to multiple variables such as clothing type and quantity, amount of insulating fat on the victim, environmental humidity or personal dampness such as after exertion, the circumstances surrounding the hypothermic episode, and so on. Heat is lost much faster in water, hence the need for wetsuits or drysuits in cold-weather activities such as kayaking. Water temperatures that would be quite reasonable as outdoor air temperatures can lead to hypothermia very quickly. For example, a water temperature of 10 °C (50 °F) can be expected to lead to death in approximately 1 hour, and water temperatures hovering at freezing can lead to death in as little as 15 minutes. On the other end of the scale, in water even a temperature as high as 26 °C (80 °F) may eventually (after many hours) lead to mild hypothermia.
Alcohol consumption prior to cold exposure may increase one's risk of becoming hypothermic. Alcohol acts as a vasodilator, increasing blood flow to the body's extremities, thereby increasing heat loss. Ironically, this may cause the victim to feel warm while rapidly losing heat to the surrounding environment.
The United States Coast Guard promotes using life vests as a method of protection against hypothermia through the 50/50/50 rule: If someone is in 50 °F water for 50 minutes, he/she has a 50 percent better chance of survival if wearing a life jacket.

Hari Merdeka

Hari Merdeka (Independence Day) is a national day of Malaysia commemorating the independence of the Federation of Malaya from British colonial rule, celebrated on August 31. In a wider context, it is to celebrate the formation of Malaysia.


Tunku Abdul Rahman Putra Al-Haj announced the independence of Malaya from the British on August 31, 1957 at Stadium Merdeka

Malaya Independence
The effort for independence was spearheaded by Tunku Abdul Rahman Putra Al-Haj, the first Prime Minister of Malaysia, who led a delegation of ministers and political leaders of Malaya in negotiations with the British in London for Merdeka, or independence along with the first president of the Malayan Chinese Association (MCA) Tun Dato Sir Tan Cheng Lock and fifth President of Malaysian Indian Congress Tun V.T. Sambanthan. Once it became increasingly clear that the Communist threat posed during the Malayan Emergency was petering out, agreement was reached on February 8, 1956, for Malaya to gain independence from the British Empire. However, for a number of logistical and administrative reasons, it was decided that the official proclamation of independence would only be made the next year, on August 31, 1957, at Stadium Merdeka (Independence Stadium), in Kuala Lumpur.

The formation of Malaysia
The Federation of Malaysia, comprising the States of Malaya, North Borneo (later renamed Sabah), Sarawak and Singapore was to be officially declared on the date August 31, 1963, on the 6th anniversary of Malayan independence. However, it was postponed to September 16, 1963, mainly due to Indonesian and the Philippines' opposition to the formation of Malaysia. Nevertheless, North Borneo and Singapore declared sovereignty on August 31, 1963. Indonesian opposition later escalated to a military conflict. Indonesia considered Malaysia as a new form of colonization on the provinces of Sarawak and Sabah in the island of Borneo (bordering Kalimantan, Indonesia), which they laid claim on. To assure Indonesia that Malaysia was not a form of neo-colonialism, a referendum, organized by the United Nations, and the Cobbold Commission, led by Lord Cobbold, were formed to determine whether the people of Sabah and Sarawak wished to join Malaysia. Their eventual findings which indicated substantial support for Malaysia among the peoples of Sabah and Sarawak, cleared the way for the final proclamation of Malaysia.
The formation of the Federation of Malaysia was then announced on September 16, 1963 as Malaysia Day. The Independence Day celebration is still held on August 31, the original independence date of Malaya. However, this has caused some minor discontent among East Malaysians in particular since it has been argued that celebrating the national day on August 31 is too Malaya-centric.

Modern Malaysia
In 1970, 75 percent of Malaysians living below the poverty line were Malays, the majority of Malays were still rural workers, and Malays were still largely excluded from the modern economy. The government’s response was the New Economic Policy of 1971, which was to be implemented through a series of four five-year plans from 1971 to 1990. The plan had two objectives: the elimination of poverty, particularly rural poverty, and the elimination of the identification between race and economic function. This latter policy was understood to mean a decisive shift in economic power from the Chinese to the Malays.
Poverty was tackled through an agricultural policy which resettled 250,000 Malays on newly cleared farmland, more investment in rural infrastructure, and the creation of free trade zones in rural areas to create new manufacturing jobs. During the 1970s and ‘80s rural poverty did decline, particularly in the Malayan Peninsula, but critics of the government’s policy contend that this was mainly due to the growth of overall national prosperity (due in large part to the discovery of important oil and gas reserves) and migration of rural people to the cities rather than to state intervention. Little was done to improve the living standards of the low-paid workers in plantation agriculture, although this group steadily declined as a proportion of the workforce. By 1990 the poorest parts of Malaysia were rural Sabah and Sarawak, which lagged significantly behind the rest of the country. These years saw rapid growth in Malaysian cities, particularly Kuala Lumpur, which became a magnet for immigration both from rural Malaya and from poorer neighbours such as Indonesia, Bangladesh, Thailand and the Philippines. Urban poverty became a problem for the first time, with shanty towns growing up around the cities. The second arm of government policy, driven mainly by Mahathir first as Education Minister and then as Prime Minister, was the transfer of economic power to the Malays. Mahathir greatly expanded the number of secondary schools and universities throughout the country, and enforced the policy of teaching in Malay rather than English. This had the effect of creating a large new Malay professional class. It also created an unofficial barrier against Chinese access to higher education, since few Chinese are sufficiently fluent in Malay to study at Malay-language universities. Chinese families therefore sent their children to universities in Singapore, Australia, Britain or the United States – by 2000, for example, 60,000 Malaysians held degrees from Australian universities. This had the unintended consequence of exposing large numbers of Malaysians to life in Western countries, creating a new source of discontent. Mahathir also greatly expanded educational opportunities for Malay women – by 2000 half of all university students were women.
Malaysia’s rapid economic progress since 1970, which was only temporarily disrupted by the Asian financial crisis of 1997, has not been matched by change in Malaysian politics. The repressive measures passed in 1970 remain in place. Malaysia has had regular elections since 1974, and although campaigning is reasonably free at election time, it is in effect a one-party state, with the UMNO-controlled National Front usually winning nearly all the seats.

Abutment

An abutment is, generally, the point where two structures or objects meet.
Specifically, an abutment may be:
the part of a structure that supports an arch.
the tooth or teeth that support a fixed or removable bridge.
the part of an implant that acts as an connection between the implant and the crown

Bridge Abutments

An abutment is an end support of a bridge superstructure.
Abutments are used for the following purposes:
to transmit the loads of from the superstructure to the foundations.
support the bearing devices.
support the backwalls.
There are different types of abutments including:
Footing-Type Abutments - each has a footing, sill and end dam, 25-30 foot spans
Pile Abutments - consist of steel or timber and can support spans of any length
Concrete Abutments - the most permanent type, and can span any length with a max height of 20 ft.

Other Civil Engineering Applications of Abutments

Abutment is also a term used by civil engineers in dam construction; moving water from a large reservoir to a channel such as a spillway, there are smooth transition walls at both sides named abutments which minimize the water's energy loss

Lake Berryessa's Glory Hole

Cross section of a spillway

Abutments in Prosthetic and Implant Dentistry

Abutment is also the term for a connecting element used to attach prosthetics to a dental implant that is Osseointegrated. These are usually called prosthetic implant abutments. These abutments can be made from a variety of materials, such as titanium, surgical stainless steel and gold. More modern abutments are now also made from zirconia, which is a white ceramic, to better complement the aesthetics of a dental implant restoration. The two images to the right show a ceramic abutment and the ceramic crown bonded to it.
Prosthetic abutments are connected to the dental implants via a screw. This screw needs to be tightened to a predetermined torque, in order to avoid screw loosening during chewing, which can often create a counter-clockwise torque on the implant-abutment interface, encouraging the abutment screw to come loose. This can largely be prevented with proper screw design and torquing of the abutment.
The images to the right show how a ceramic abutment can enhance a ceramic crown by giving it a more life-like appearance. Ceramic abutments have to be used with care, however, since their compressive strength is nowhere near that of titanium, gold or other noble metals. Most clinicians feel more comfortable using a metal prosthetic abutment in the posterior molar areas, due to the increased masticatory forces present in these areas.

Ceramic Abutment connected to implant

Ceramic crown bonded to abutment

Ramadan

Ramadan (Arabic: رمضان‎) (also written Ramazan, Ramzan, Ramadhan, Ramdan, Ramadaan) is an Islamic religious observance that takes place during the ninth month of the Islamic calendar; the month in which the Qur'an was revealed[Qur'an 2:185] to the Prophet Muhammad. In the western calendar, the dates of Ramadan vary, moving forward about ten days each year. It is the Islamic month of fasting, in which participating Muslims refrain from eating, drinking, sexual conduct, smoking, and indulging in anything that is in excess or ill-natured; from dawn until sunset Fasting is meant to teach the Muslim patience, modesty and spirituality. Ramaḍān is a time to fast for the sake of Allah, and to offer more prayer than usual. Muslims also believed through good actions, they get rewarded seventy times as much as they normally can achieve. During Ramaḍān, Muslims ask forgiveness for past sins, pray for guidance and help in refraining from everyday evils, and try to purify themselves through self-restraint and good deeds.

Origins of Ramadan

The name "Ramaḍāma" had been the name of the ninth month in the Arab world long before the arrival of Islam; the word itself derived from an Arabic root rmḍ, as in words like "ramiḍa" or "ar-ramaḍ" denoting intense heat, scorched ground and shortness of rations. In the Qu'ran, God proclaims that "fasting has been written down (as obligatory) upon you, as it was upon those before you". According to the earliest hadith, this refers to the Jewish practice of fasting on Yom Kippur.
Laylat al-Qadr, considered the most holy night of the year, is the night in which the Qur'an was revealed to Muhammad, the "Night of the Power". Muslims believe it to have occurred on an odd-numbered night during the last 10 days of Ramaḍān, either the night of the 21st, 23rd, 25th, 27th or 29th (in Sunni thought) or the 19th, 21st or 23rd (in Shi'a thought). Ramaḍān ends with Eid ul-Fitr, with much celebration and feasts. During the month following Ramaḍān, called Shawwal, Muslims are encouraged to fast for a further six days, known as as-Sitta al-Bīḍ, or "the white six." When fasting is over, Muslims go to Mosques in new clothes to pray the first Eid prayer. They give out presents to the young ones and greet their friends and families. They then thank God for what He has given them.

Practices during Ramaḍān

Fasting

The most prominent event of this month is fasting. Every day during the month of Ramadan, Muslims around the world get up before dawn to eat Sahur, the pre-dawn meal, then they perform the fajr prayer. They have to stop eating and drinking before the call for prayer starts until the fourth prayer of the day, Maghrib. Muslims may continue to eat and drink after the sun has set until the next morning's fajr prayer call. Then the process starts all over.
Ramadān is a time of reflecting and worshiping God. Muslims are expected to put more effort into following the teachings of Islam and to avoid obscene and irreligious sights and sounds. Sexual thoughts and activities during fasting hours are also forbidden.[Qur'an 2:187] Purity of both thought and action is important. The fast is intended to be an exacting act of deep personal worship in which Muslims seek a raised awareness of closeness to God.
The act of fasting is said to redirect the heart away from worldly activities, its purpose being to cleanse the inner soul and free it from harm. It also allows Muslims to practice self-discipline, self-control, sacrifice, and empathy for those who are less fortunate; thus encouraging actions of generosity and charity. However, a certain level of self-control can be lost by those who suffer from eating disorders.
The elderly, the chronically ill, and the mentally ill are exempt from fasting, although the first two groups must endeavor to feed the poor in place of their missed fasting. Also exempt are pregnant women, women during the period of their menstruation, and women nursing their newborns. A difference of opinion exists among Islamic scholars as to whether this last group must make up the days they miss at a later date, or feed poor people as a recompense for days missed. While fasting is not considered compulsory in childhood, many children endeavor to complete as many fasts as possible as practice for later life. Lastly, those traveling are exempt, but must make up the days they miss.[Qur'an 2:184] More specifically, Twelver Shī‘ah define those who travel more than 14 miles in a day as exempt. The elderly or those who suffer from a disability or disease and have no prospect of getting better in the future can pay the cost of Iftar for a person who cannot afford it, or else they can host him in their house and have him eat with them after sunset as a way of repaying for the days they could not fast. [Qur'an 2:184]
A person who is observing Ramadan might break the fast accidentally, due to having forgotten it. In such an instance, one should spit out the food being eaten or cease the forbidden activity, immediately upon remembering the fast.
When Ramadan came to overshadow Ashura in importance, it took on some characteristics of the latter. According to the well-known hadith, the person who observes Ramadan properly will have all their past sins forgiven. According to another, "When Ramadan arrives, Heaven's gates are opened, Hell's gates are closed, and the demons are chained up" and who ever passes away will enter paradise.

Prayer and reading of the Qur'an

In addition to fasting, Muslims are encouraged to read the entire Qur'an. Some Muslims perform the recitation of the entire Qur'an by means of special prayers, called Tarawih, which are held in the mosques every night of the month, during which a whole section of the Qur'an (juz, which is 1/30 of the Qur'an) is recited. Therefore the entire Qur'an would be completed at the end of the month.
Ramadān is also a time when Muslims are to slow down from worldly affairs and focus on self-reformation, spiritual cleansing and enlightenment, establishing a link between themselves and God through prayer, supplication, charity, good deeds, kindness and helping others. Since it is a festival of giving and sharing, Muslims prepare special foods and buy gifts for their family and friends and for giving to the poor and needy who cannot afford it; this can involve buying new clothes, shoes and other items of need. There is also a social aspect involved the preparing of special foods and inviting people for the Iftar meal (the meal to open the fast).
In many Muslim and non Muslim countries with large Muslim populations, markets close down in the evening to enable people to perform prayers and consume the Iftar meal – these markets then re-open and stay open for a good part of the night. Muslims can be seen shopping, eating, spending time with their friends and family during the evening hours. In some Muslim countries, failing to fast or openly flaunting such behavior during Ramadan is considered a crime and is prosecuted as such.

Eid ul-Fitr

The Islamic holiday of Eid ul-Fitr (Arabic: عيد الفطر‎) marks the end of the fasting period of Ramadan and the first day of the following month, after another new moon has been sighted. The Eid falls after 29 or 30 days of fasting, as per the lunar sighting. Eid ul-Fitr means the Festival of Breaking the Fast; a special celebration is made. Food is donated to the poor (‘Zakat al-Fitr’), everyone puts on their best, usually new, clothes, and communal prayers are held in the early morning, followed by feasting and visiting relatives and friends. The prayer is two rakaahs only, and it is optional (Wajib) prayer as opposed to the compulsory five daily prayers.

Oldest Tree

Pinus longaeva

Pinus longaeva, the Great Basin Bristlecone Pine, is a long-living species of tree found in the higher mountains of the southwest United States. The species is one of three closely related trees known as bristlecone pines and is sometimes known as the Intermountain or Western bristlecone pine.

Physical characteristics

It is a medium-size tree, reaching 5 to 15 m (16 to 49 ft) tall and with a trunk diameter of up to 2.5 to 3.6 m (8 ft 2 in to 11 ft 10 in) in diameter. The bark is bright orange-yellow, thin and scaly at the base of the trunk. The leaves ('needles') are in fascicles of five, stout, 2.5 to 4 cm (0.98 to 1.6 in) long, deep green to blue-green on the outer face, with stomata confined to a bright white band on the inner surfaces. The leaves show the longest persistence of any plant, with some remaining green for 45 years (Ewers & Schmid 1981).
The cones are ovoid-cylindrical, 5 to 10 cm (2.0 to 3.9 in) long and 3 to 4 cm (1.2 to 1.6 in) broad when closed, green or purple at first, ripening orange-buff when 16 months old, with numerous thin, fragile scales, each scale with a bristle-like spine 2 to 5 mm (0.079 to 0.20 in) long. The cones open to 4 to 6 cm (1.6 to 2.4 in) broad when mature, releasing the seeds immediately after opening. The seeds are 5 mm (0.20 in) long, with a 12 to 22 mm (0.47 to 0.87 in) wing; they are mostly dispersed by the wind, but some are also dispersed by Clark's Nutcrackers, which pluck the seeds out of the opening cones.

The nutcrackers use the seeds as a food resource, storing many for later use, and some of these stored seeds are not used and are able to grow into new plants. However, in many stands current reproduction is not adequate to replace old and dying trees.
It differs from Pinus aristata in that the needles always have two resin canals, and these are not interrupted and broken, so it lacks the characteristic small white resin flecks appearing on the needles in that species. From the Foxtail Pine, it differs in the cone bristles being over 2 mm (0.079 in) long, and the cones having a more rounded (not conic) base.

Distribution

The species occurs in Utah, Nevada and eastern California. In California, it is restricted to the White Mountains, the Inyo Mountains, and the Panamint Range, in Mono and Inyo counties.

A specimen of Pinus longaeva

In Nevada, it is found in most of the higher ranges of the Basin and Range from the Spring Mountains near Las Vegas north to the Ruby Mountains, and in Utah, northeast to South Tent in the Wasatch Range.

Age

A specimen of this species nicknamed "Methuselah" located in the Ancient Bristlecone Pine Forest of the White Mountains near Bishop, California is 4,700 years old, as measured by annual ring count on a small core taken with an increment borer. Its exact location is kept secret, since an older specimen, nicknamed "Prometheus", was cut down in 1964. It is the oldest known tree in North America, and the oldest known individual tree in the world, although a clonal individual, nicknamed "Old Tjikko", a Norway Spruce in Sweden is 9,550 years old.
Among the White Mountain specimens, the oldest trees are found on north-facing slopes, with an average of 2,000 years, as compared to the 1,000 year average on the southern slopes. The climate and the durability of their wood can preserve them long after death, with dead trees as old as 7,000 years persisting next to live ones.

Cupressus sempervirens

Cupressus sempervirens, the Mediterranean Cypress (also known as Italian, Tuscan, or Graveyard Cypress, or Pencil Pine) is a species of cypress native to the eastern Mediterranean region, in northeast Libya, southeast Greece (Crete, Rhodes), southern Turkey, Cyprus, western Syria, Lebanon, Israel and western Jordan, and also a disjunct population in Iran.
It is a medium-sized evergreen tree to 35 m (115 ft) tall, with a conic crown with level branches and variably loosely hanging branchlets. It is very long-lived, with some trees reported to be over 1,000 years old.
The foliage grows in dense sprays, dark green in colour. The leaves are scale-like, 2-5 mm long, and produced on rounded (not flattened) shoots. The seed cones are ovoid or oblong, 25-40 mm long, with 10-14 scales, green at first, maturing brown about 20–24 months after pollination. The male cones are 3-5 mm long, and release pollen in late winter.
It is moderately susceptible to cypress canker, caused by the fungus Seridium cardinale, and can suffer extensive dieback where this disease is common.
The species name sempervirens comes from the Latin for 'evergreen'.

Uses

Mediterranean Cypress has been widely cultivated as an ornamental tree for millennia away from its native range, mainly throughout the central and western Mediterranean region, and in other areas with similar hot, dry summers and mild, rainy winters, including California, southwest South Africa and southern Australia. It can also be grown successfully in areas with cooler, moister summers, such as the British Isles, New Zealand and the Pacific Northwest (coastal Oregon, Washington and British Columbia).
The vast majority of the trees in cultivation are selected cultivars with a fastigiate crown, with erect branches forming a narrow to very narrow crown often less than a tenth as wide as the tree is tall. The dark green 'exclamation mark' shape of these trees is a highly characteristic signature of Mediterranean town and village landscapes. Cypress used to be used in distilleries as staves to hold mash ferments to make alcohol before the invention of stainless steel.

Déjà vu

Déjà vu (diucapkan / deɪʒɑ ː vu ː / (mendengarkan); Perancis: [deʒa Vỹ] (mendengarkan), "sudah mulai"; juga disebut paramnesia, dari Yunani παρα "untuk", "dekat, terhadap, bertentangan dengan" + μνήμη "mnēmē "," memori ") atau promnesia, adalah pengalaman merasa yakin bahawa telah menyaksikan atau mengalami situasi yang baru sebelumnya (individu merasa seolah-olah sebuah perkara sudah terjadi atau yang telah terjadi di masa lalu), walaupun keadaan yang tepat dari sebelumnya dan mengalami ketidakpastian. Istilah ini dicipta oleh seorang pengkaji fizik Perancis, emile Boirac (1851-1917) dalam bukunya "L'Avenir des sciences psychiques" ("The Future of Psychic Sciences"), yang diperluas setelah dia menulis sebuah karangan semasa masih menuntut. Pengalaman Déjà vu biasanya disertai oleh rasa keakraban menarik, dan juga rasa "kengerian", "keadaan tidak dikenal," atau "weirdness." Yang "sebelumnya" pengalaman yang paling sering dikaitkan dengan mimpi, meskipun dalam beberapa keadaan ada perasaan yang mengalami rasa "benar-benar terjadi" di masa lalu. Pengalaman Déjà vu kelihatannya cukup umum di kalangan orang dewasa dan kanak-kanak. Referensi ke pengalaman Déjà vu juga ditemukan dalam sastera di masa lalu, menunjukkan itu bukanlah sebuah fenomena baru, ia sangat sulit untuk membangkitkan yang Déjà Vu merupakan perihal pengalaman, sehingga membuatnya menjadi subjek dari beberapa kajian. Baru-baru ini, para penyelidik telah menemukan cara untuk mencipta sensasi ini menggunakan kaedah hypnosis.

Kajian Saintifik
Sejak tahun terakhir dari abad ke-20, Déjà Vu telah dikaji secara serius didalam penelitian psikologis dan neurophysiological. Bercakap secara ilmiah, penjelasan Déjà vu tidak hanya suatu tindakan "precognition" atau "prophecy", tetapi itu adalah anomali dari memori dan memberi kesan bahawa sebuah pengalaman "being recalled." Ini adalah penjelasan atau hujah oleh fakta bahawa rasa "dingin" pada waktu yang kuat dalam banyak keadaan, tetapi keadaan yang "sebelumnya" pengalaman (bila, dimana dan bagaimana pengalaman sebelumnya terjadi) cukup samar-samar ini dapat dipameran dari ingatan yang kuat yang memiliki "unsettling" pengalaman Déjà vu itu sendiri, tetapi sedikit atau tidak ada ingatan yang spesifik atau perkara mereka "mengingat" ketika mereka yang mengalami Déjà vu. Secara khusus, hal ini dapat dari hasil tumpang tindih antara sistem neurological dan bertanggungjawab untuk memori jangka pendek (peristiwa yang dianggap sebagai hadir dalam) dan orang-orang yang bertanggungjawab untuk jangka panjang memori (peristiwa yang dianggap sebagai berada di masa lalu). Susunan perkara yang disimpan ke dalam memori sebelum adalah sedar sebahagian dari otak bahkan menerima informasi dan proses itu. Lain teori yang dieksplorasi adalah visi. Menunjukkan sebagai teori, salah satu mata akan merakam apa yang dilihat fractionally lebih cepat dari yang lain, yang membuat "ingatan kuat" sensasi atau "sama" pemandangan yang dilihat oleh milidetik kemudian di mata yang sebaliknya. Namun, ini gagal untuk menjelaskan fenomena lainnya yang terlibat, seperti bahagian auditive, terutama bahagian digital. Jika satu, misalnya, pengalaman Déjà vu dari seseorang yang kuat pada jari tangan kiri, maka Déjà vu merasa sudah tentu tidak kerana sebelah kanannya mengalami sensasi yang sama lebih dari itu mengingat bahwa tangan kiri sebelah kananya tidak akan pernah menerima input sama. Selain itu, seseorang danagn hanya satu mata masih juga akan mengalami Déjà Vu Déjà vécu (gangguan memori, mirip dengan Déjà vu berterusan).

Penerangan Alternatif
Penerangan Mistik
Déjà vu berkaitan dengan precognition, kebolehan pandang secara terus, dan sering disebut sebagai bukti untuk "psikis" kemampuan dalam masyarakat umum. Penjelasan dari bukti-bukan ilmiah menjelaskan, sifat pengalaman untuk ramalan, penglihatan (seperti yang diterima dalam mimpi), atau hidup-kenangan masa lalu. Beberapa masih percaya bahwa Déjà vu adalah sekilas tentang kehidupan yang sudah, misalnya ketika Anda membuat pilihan dalam kehidupan ini dan akan membawa Anda ke bawah jalan tertentu, bila Anda berada di jalur yang Anda miliki, sekilas hidup anda yang membuat berbagai pilihan.

Mimpi
Beberapa percaya Déjà vu adalah memori mimpi. Walaupun sebagian besar mimpi tidak pernah diingat, orang yang bermimpi dapat menampilkan aktiviti di kawasan otak yang memproses memori jangka panjang. Telah dispekulasi bahwa mimpi langsung ke memori jangka panjang, melangkaui memori jangka pendek secara keseluruhan. Dalam hal ini, Déjà vu mungkin memori yang lupa dengan elemen mimpi di umum dengan pengalaman yang sedang berjaga-jaga. Hal ini mungkin serupa dengan yang lain dikenal sebagai fenomena Déjà rêvé, atau "sudah bermimpi." Namun, kajian pada tikus menunjukkan bahawa jangka panjang kenangan pertama harus ditetapkan sebagai memori jangka pendek.

Penjelmaan Semula

Mereka yang percaya penjelmaan semula berteori bahawa Déjà vu disebabkan oleh fragmen-hidup dari masa lalu menjadi kenangan menyentak ke permukaan yang diketahui oleh orang. Lain berteori bahwa fenomena ini disebabkan oleh semangat bintang, atau di luar tubuh pengalaman (OBEs), di mana mungkin saja ada orang yang dikunjungi di tempat sementara mereka dgn bintang selama seseorang itu tidur. Sensasi ini mungkin juga diinterpretasikan sebagai pemenuhan terhubung ke suatu kondisi seperti yang terlihat atau dirasakan dalam firasat.

Ibnu Sina

Abu Ali al Husain ibn Abdallah ibn Sina, itulah nama lengkap Ibnu Sina. Ia lahir di Afsana, sebuah kota kecil dekat dengan kota Bukhara, tempat asal ahli hadits ternama Bukhari, pada tahun 981.
Ibnu Sina yang lebih dikenali di Barat dengan nama Avicenna mempunyai nama lengkap Abu Ali al- Huseyn bin Abdullah bin Hassan Ali bin Sina. Beliau merupakan seorang yang berbangsa Parsi. Menurut Ibnu Abi Ushaybi’ah ia lahir pada tahun 375 H, di desa Afshanah dekat kota Kharmaitan Propinzi Bukhara Afghanistan.

ibnu sina

Pelajaran pertama yang diterimanya pada zaman kanak-kanak adalah Al-Quran dan sastera yang didapati olehnya secara tidak formal. Ia mula belajar pada usia 5 tahun. Sementara itu sewaktu berumur 10 tahun , beliau telah berjaya menghafal Al-Quran. Pada masa umurnya meningkat 18 tahun Ibnu Sina telah menjadi "Doktor Di Raja". Disamping itu, Ibnu Sina juga telah menguasai seluruh cabang ilmu pengetahuan yang ada pada waktu itu. Ilmu-ilmu agama seperti tafsir, fiqh, perbandingan agama (ushuluddin), tasawuf dan sebagainya sudah dikuasainya ketika baru berusia 10 tahun. Pada masa kecilnya, ia dibimbing dan dididik oleh Abu Abdullah Natili, seorang sahabat karib ayahnya, dan ayahnya sendiri. Antara bidang ilmu yang berjaya dikuasainya termasuklah dalam bidang falsafah, kedoktoran, geometri, astronomi, muzik, syair, teologi, politik, matematik, fizik, kimia, sastera dan kosmologi.
Walaupun Ibnu Sina menguasai pelbagai ilmu pengetahuan termasuk falsafah tetapi beliau lebih menonjol dalam bidang perubatan sama ada sebagai seorang doktor ataupun mahaguru ilmu tersebut.
Ibnu Sina mula menjadi terkenal selepas berjaya menyembuhkan penyakit Putera Nub Ibn Nas al-Samani yang gagal diubati oleh doktor yang lain. Kehebatan dan kepakaran dalam bidang perubatan tiada tolok bandingnya sehingga beliau diberikan gelaran al-Syeikh al-Rais (Mahaguru Pertama).

Teori-Teori Anatomi Dan Fisiologi

Teori-teori anatomi dan fisiologi dalam buku-buku beliau adalah menggambarkan analogi manusia terhadap negara dan mikrokosmos (dunia kecil) terhadap alam semester sebagai makrokosmos (dunia besar). Misalnya digambarkan bahawa syurga kayangan adalah bulat dan bumi adalah persegi dan dengan demikian kepala itu bulat dan kaki itu empat persegi. Terdapat empat musim dan 12 bulan dalam setahun, dengan itu manusia memiliki empat tangkai dan lengan (anggota badan) mempunyai 12 tulang sendi. Hati (heart) adalah ‘pangeran’-nya tubuh manusia, sementera paru-paru adalah ‘menteri’-nya. Leher merupakan ‘jendela’-nya sang badan, manakala kandung empedu sebagai ‘markas pusat’-nya. Limpa dan perut sebagai ‘bumbung’ sedangkan usus merupakan sistem komunikasi dan sistem pembuangan.
Sementara itu "Canon of Medicine" memuatkan pernyataan yang tegas bahawa "darah mengalir secara terus-menerus dalam suatu lingkaran dan tak pernah berhenti" . Namun ini belum dapat dianggap sebagai suatu penemuan tentang srikulasi darah, kerana bangsa cina tidak membezakan antara urat-urat darah halus (Veins) dengan pembuluh nadi (arteries). Analogi tersebut hanyalah analogi yang digambarkan antara gerakan darah dan siklus alam semesta, pergantian musim dan gerakan-gerakan tubuh tanpa peragaan secara empirik pada keadaan yang sebenarnya.

makam ibnu sina (bahagian dalam)

Pengaruh Ibnu Sina (Avicenna)

Pengaruh Ibnu Sina sebagai seorang failasuf dan doktor perubatan dalam kebudayaan Eropah adalah luas. Buku karangannya al-Qanun Fit- Tibb (Peraturan Perubatan) terdiri daripada 14 jilid, telah dianggap sebagai himpunan perbendaharaan ilmu perubatan. Ilmu perubatan moden banyak mendapat pelajaran daripada Ibnu Sina, dari segi pengunaan ubat, diagnosis dan pembedahan.

Terjemahan Dan Bahan Rujukan al-Qanun Fit- Tibb

Pada abad ke 12 M Gerard Cremona yang berpindah ke Toledo, Sepanyol telah menterjemahkan buku Ibnu Sina ke bahasa Latin. Buku ini menjadi buku rujukan utama di universiti-universiti Eropah hingga 1500 M. Bukunya telah disalin (cetak ) sebanyak 16 kali dan 15 edisi dalam bahasa Latin dan sebuah edisi dalam bahasa Yahudi (Hebrew).Disamping itu buku tersebut turut diterjemahkan ke dalam bahasa Inggeris, Perancis , Sepanyol dan Itali . Pada abad ke 16 M , buku ini dicetak 21 kali.
Al-Qanun Fit-Tibb juga digunakan sebagai buku teks kedoktoran di berbagai universiti di Perancis. Misalnya di Sekolah Tinggi Kedoktoran Montpellier dan Louvin telah menggunakannya sebagai bahan rujukan pada abad ke 17 M. Sementara itu Prof. Phillip K. Hitpi telah menganggap buku tersebut sebagai "Ensiklopedia Kedoktoran".
Penulis- penulis Barat telah menganggap Ibnu Sina sebagai ‘Bapa Doktor’ kerana Ibnu Sina telah menyatupadukan teori perubatan Yunani Hippocrates dan GALEN dan pengalaman dari ahli-ahli perubatan dari India dan Parsi dan pengalaman beliau sendiri.

Aristotle

Aristotle (Greek: Ἀριστοτέλης, Aristotélēs) (384 BC – 322 BC) was a Greek philosopher, a student of Plato and teacher of Alexander the Great. He wrote on many subjects, including physics, metaphysics, poetry, theater, music, logic, rhetoric, politics, government, ethics, biology and zoology.
Together with Plato and Socrates (Plato's teacher), Aristotle is one of the most important founding figures in Western philosophy. He was the first to create a comprehensive system of Western philosophy, encompassing morality and aesthetics, logic and science, politics and metaphysics. Aristotle's views on the physical sciences profoundly shaped medieval scholarship, and their influence extended well into the Renaissance, although they were ultimately replaced by Newtonian Physics. In the biological sciences, some of his observations were confirmed to be accurate only in the nineteenth century. His works contain the earliest known formal study of logic, which was incorporated in the late nineteenth century into modern formal logic. In metaphysics, Aristotelianism had a profound influence on philosophical and theological thinking in the Islamic and Jewish traditions in the Middle Ages, and it continues to influence Christian theology, especially Eastern Orthodox theology, and the scholastic tradition of the Catholic Church. All aspects of Aristotle's philosophy continue to be the object of active academic study today.

Life
Aristotle was born in Stageira, Chalcidice, in 384 BC, about 55 km (34 mi) east of modern-day Thessaloniki. His father Nicomachus was the personal physician to King Amyntas of Macedon. Aristotle was trained and educated as a member of the aristocracy. At about the age of eighteen, he went to Athens to continue his education at Plato's Academy. Aristotle remained at the academy for nearly twenty years, not leaving until after Plato's death in 347 BC. He then traveled with Xenocrates to the court of his friend Hermias of Atarneus in Asia Minor. While in Asia, Aristotle traveled with Theophrastus to the island of Lesbos, where together they researched the botany and zoology of the island. Aristotle married Hermias's adoptive daughter (or niece) Pythias. She bore him a daughter, whom they named Pythias. Soon after Hermias' death, Aristotle was invited by Philip II of Macedon to become the tutor to his son Alexander the Great in 343 B.C.
Aristotle was appointed as the head of the royal academy of Macedon. During that time he gave lessons not only to Alexander, but also to two other future kings: Ptolemy and Cassander. In his Politics, Aristotle states that only one thing could justify monarchy, and that was if the virtue of the king and his family were greater than the virtue of the rest of the citizens put together. Tactfully, he included the young prince and his father in that category. Aristotle encouraged Alexander toward eastern conquest, and his attitude towards Persia was unabashedly ethnocentric. In one famous example, he counsels Alexander to be 'a leader to the Greeks and a despot to the barbarians, to look after the former as after friends and relatives, and to deal with the latter as with beasts or plants'. Near the end of Alexander's life he began to suspect plots, and threatened Aristotle in letters. Aristotle had made no secret of his contempt for Alexander's pretense of divinity, and the king had executed Aristotle's grandnephew Callisthenes as a traitor. A widespread tradition in antiquity suspected Aristotle of playing a role in Alexander's death, but there is little evidence for this.

Early Islamic portrayal of Aristotle

Aristotle's scientific method
Like his teacher Plato, Aristotle's philosophy aims at the universal. Aristotle, however, found the universal in particular things, which he called the essence of things, while Plato finds that the universal exists apart from particular things, and is related to them as their prototype or exemplar. For Aristotle, therefore, philosophic method implies the ascent from the study of particular phenomena to the knowledge of essences, while for Plato philosophic method means the descent from a knowledge of universal Forms (or ideas) to a contemplation of particular imitations of these. For Aristotle, "form" still refers to the unconditional basis of phenomena but is "instantiated" in a particular substance (see Universals and particulars, below). In a certain sense, Aristotle's method is both inductive and deductive, while Plato's is essentially deductive from a priori principles.
In Aristotle's terminology, "natural philosophy" is a branch of philosophy examining the phenomena of the natural world, and includes fields that would be regarded today as physics, biology and other natural sciences. In modern times, the scope of philosophy has become limited to more generic or abstract inquiries, such as ethics and metaphysics, in which logic plays a major role. Today's philosophy tends to exclude empirical study of the natural world by means of the scientific method. In contrast, Aristotle's philosophical endeavors encompassed virtually all facets of intellectual inquiry.
In the larger sense of the word, Aristotle makes philosophy coextensive with reasoning, which he also would describe as "science". Note, however, that his use of the term science carries a different meaning than that covered by the term "scientific method". For Aristotle, "all science (dianoia) is either practical, poetical or theoretical" (Metaphysics 1025b25). By practical science, he means ethics and politics; by poetical science, he means the study of poetry and the other fine arts; by theoretical science, he means physics, mathematics and metaphysics.
If logic (or "analytics") is regarded as a study preliminary to philosophy, the divisions of Aristotelian philosophy would consist of: (1) Logic; (2) Theoretical Philosophy, including Metaphysics, Physics, Mathematics, (3) Practical Philosophy and (4) Poetical Philosophy.

Legacy
Twenty-three hundred years after his death, Aristotle remains one of the most influential people who ever lived. He was the founder of formal logic, pioneered the study of zoology, and left every future scientist and philosopher in his debt through his contributions to the scientific method.
Despite these accolades, many of Aristotle's errors held back science considerably. Bertrand Russell notes that "almost every serious intellectual advance has had to begin with an attack on some Aristotelian doctrine". Russell also refers to Aristotle's ethics as "repulsive", and calls his logic "as definitely antiquated as Ptolemaic astronomy". Russell notes that these errors make it difficult to do historical justice to Aristotle, until one remembers how large of an advance he made upon all of his predecessors. Of course, the problem of excessive devotion to Aristotle is more a problem of those later centuries and not of Aristotle himself.
Aristotle believed that women are colder than men and thus a lower form of life. His assumption unfortunately carried forward unexamined to Galen and others for almost two thousand years until the sixteenth century. He also believed that females could not be fully human. His analysis of procreation is frequently criticized on the grounds that it presupposes an active, ensouling masculine element bringing life to an inert, passive, lumpen female element; it is on these grounds that Aristotle is considered by some feminist critics to have been a misogynist. On the other hand, Aristotle gave equal weight to women's happiness as he did to men's, and commented in his Rhetoric that a society cannot be happy unless women are happy too. In places like Sparta where the lot of women is bad, there can only be half-happiness in society.

Muhammad ibn Zakariya al-Razi

Abū Bakr Muhammad ibn Zakariyā Rāzī (Zakariā-ye Rāzi: Persian: زكريای رازی), known as Rhazes or Rasis after medieval Latinists, (August 26 865, Rayy— 925, Rayy) was a Persian alchemist, chemist, physician, philosopher and scholar. He is recognised as a polymath and often referred as "probably the greatest and most original of all the Muslim physicians, and one of the most prolific as an author".
He made fundamental and enduring contributions to the fields of medicine, alchemy, music, and philosophy, recorded in over 184 books and articles in various fields of science. He was well-versed in Persian, Greek and Indian medical knowledge and made numerous advances in medicine through own observations and discoveries.


Well educated in music, mathematics, philosophy, and metaphysics, he finally chose medicine as his professional field. As a physician, he was an early proponent of experimental medicine and is considered the father of pediatrics. He was also a pioneer of neurosurgery and ophthalmology. He was among the first to use Humoralism to distinguish one contagious disease from another. In particular, Razi was the first physician to distinguish smallpox and measles through his clinical characterization of the two diseases. And as an alchemist, Rhazes is known for his study of sulfuric acid and for his discovery of ethanol and its refinement to use in medicine. He became chief physician of Rayy and Baghdad hospitals.


Rhazes was a rationalist and very confident in the power of ratiocination; he was widely regarded by his contemporaries and biographers as liberal and free from any kind of prejudice and very bold and daring in expressing his ideas without a qualm.
He traveled extensively but mostly in Persia. As a teacher in medicine, he attracted students of all disciplines and was said to be compassionate and devoted to the service of his patients, whether rich or poor.

European depiction of the Persian doctor Al-Razi, in Gerard of Cremona "Receuil des traites de medecine" 1250-1260

Biography

Rhazes was born on 28 August 865 AH and died on 6 October 925AH. His name Razi in Persian means from the city of Rayy, an ancient town called Ragha in old Persian and Ragâ in Avestan. It is located on the southern slopes of the Elburz Range situated near Tehran, Iran. In this city (like Ibn Sina) he accomplished most of his work.

In his early life he could have been a musician or singer (see Ibn abi Usaibi'ah) but more likely a lute-player who shifted his interest from music to alchemy (cf. ibn Juljul, Sa'id, ibn Khallikan, Usaibi'ah, al-Safadi). At the age of 30 (Safadi says after 40) he stopped his study of alchemy because his experimentation had caused an eye-disease (Cf. al-Biruni), obliging him to search for physicians and medicine to cure it. al-Biruni, Beyhaqi and others, say this was the reason why he began his medical studies.

Contributions to medicine

Smallpox vs. measles

As chief physician of the Baghdad hospital, Razi formulated the first known description of smallpox:
"Smallpox appears when blood 'boils' and is infected, resulting in vapours being expelled. Thus juvenile blood (which looks like wet extracts appearing on the skin) is being transformed into richer blood, having the color of mature wine. At this stage, smallpox shows up essentially as 'bubbles found in wine' - (as blisters) - ... this disease can also occur at other times - (meaning: not only during childhood) -. The best thing to do during this first stage is to keep away from it, otherwise this disease might turn into an epidemic."
This diagnosis is acknowledged by the Encyclopaedia Britannica (1911), which states: "The most trustworthy statements as to the early existence of the disease are found in an account by the 9th-century Persian physician Rhazes, by whom its symptoms were clearly described, its pathology explained by a humoral or fermentation theory, and directions given for its treatment."

Razi, treating a patient

Razi's book: al-Judari wa al-Hasbah (On Smallpox and Measles) was the first book describing smallpox and measles as distinct diseases. It was translated more than a dozen times into Latin and other European languages. Its lack of dogmatism and its Hippocratic reliance on clinical observation show Razi's medical methods.

Uranium

Uranium (pronounced /jʊˈreɪniəm/) is a silvery-white metallic chemical element in the actinide series of the periodic table that has the symbol U and atomic number 92. Besides its 92 protons, a uranium nucleus can have between 141 and 146 neutrons, with 146 (U-238) and 143 (U-235) in its most common isotopes. The number of electrons in a uranium atom is 92, 6 of them valence electrons. Uranium has the highest atomic weight of the naturally occurring elements. Uranium is approximately 70% denser than lead, but not as dense as gold or tungsten. It is weakly radioactive. It occurs naturally in low concentrations (a few parts per million) in soil, rock and water, and is commercially extracted from uranium-bearing minerals such as uraninite.

silvery gray metallic; corrodes to a spalling black oxide coat in air

Uranium is used as a colorant in uranium glass, producing orange-red to lemon yellow hues. It was also used for tinting and shading in early photography. The 1789 discovery of uranium in the mineral pitchblende is credited to Martin Heinrich Klaproth, who named the new element after the planet Uranus. Eugène-Melchior Péligot was the first person to isolate the metal, and its radioactive properties were uncovered in 1896 by Antoine Becquerel. Research by Enrico Fermi and others starting in 1934 led to its use as a fuel in the nuclear power industry and in Little Boy, the first nuclear weapon used in war. An ensuing arms race during the Cold War between the United States and the Soviet Union produced tens of thousands of nuclear weapons that used enriched uranium and uranium-derived plutonium. The security of those weapons and their fissile material following the breakup of the Soviet Union in 1991 is an ongoing concern for public health and safety.

Applications
The major application of uranium in the military sector is in high-density penetrators. This ammunition consists of depleted uranium (DU) alloyed with 1–2% other elements. At high impact speed, the density, hardness, and flammability of the projectile enable destruction of heavily armored targets. Tank armor and the removable armor on combat vehicles are also hardened with depleted uranium plates. The use of DU became a contentious political-environmental issue after the use of DU munitions by the US, UK and other countries during wars in the Persian Gulf and the Balkans raised questions of uranium compounds left in the soil (see Gulf War Syndrome).
Depleted uranium is also used as a shielding material in some containers used to store and transport radioactive materials. Other uses of DU include counterweights for aircraft control surfaces, as ballast for missile re-entry vehicles and as a shielding material. Due to its high density, this material is found in inertial guidance devices and in gyroscopic compasses. DU is preferred over similarly dense metals due to its ability to be easily machined and cast as well as its relatively low cost. Counter to popular belief, the main risk of exposure to DU is chemical poisoning by uranium oxide rather than radioactivity (uranium being only a weak alpha emitter).
During the later stages of World War II, the entire Cold War, and to a lesser extent afterwards, uranium has been used as the fissile explosive material to produce nuclear weapons. Two major types of fission bombs were built: a relatively simple device that uses uranium-235 and a more complicated mechanism that uses uranium-238-derived plutonium-239. Later, a much more complicated and far more powerful fusion bomb that uses a plutonium-based device in a uranium casing to cause a mixture of tritium and deuterium to undergo nuclear fusion was built.

The most visible civilian use of uranium is as the thermal power source used in nuclear power plants.

After Marie Curie discovered radium in uranium ore, a huge industry developed to mine uranium so as to extract the radium, which was used to make glow-in-the-dark paints for clock and aircraft dials. This left a prodigious quantity of uranium as a 'waste product', since it takes three metric tons of uranium to extract one gram of radium. This 'waste product' was diverted to the glazing industry, making uranium glazes very inexpensive and abundant. In addition to the pottery glazes, uranium tile glazes accounted for the bulk of the use, including common bathroom and kitchen tiles which can be produced in green, yellow, mauve, black, blue, red and other colors.
Uranium was also used in photographic chemicals (esp. uranium nitrate as a toner), in lamp filaments, to improve the appearance of dentures, and in the leather and wood industries for stains and dyes. Uranium salts are mordants of silk or wool. Uranyl acetate and uranyl formate are used as electron-dense "stains" in transmission electron microscopy, to increase the contrast of biological specimens in ultrathin sections and in negative staining of viruses, isolated cell organelles and macromolecules.
The discovery of the radioactivity of uranium ushered in additional scientific and practical uses of the element. The long half-life of the isotope uranium-238 (4.51 × 109 years) makes it well-suited for use in estimating the age of the earliest igneous rocks and for other types of radiometric dating (including uranium-thorium dating and uranium-lead dating). Uranium metal is used for X-ray targets in the making of high-energy X-rays.

Uranium glass used as lead-in seals in a vacuum capacitor