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Ornamental Fish

Pterophyllum scalare
螢光神仙魚
Gene Transfer in Taiwan is World-Renowned
Internationally, Taiwan is a leader in biotechnology research and development. Today (May 25), a press conference at the Council of Agriculture, Executive Yuan, was held by scientists and the Jy Lin Company , the biggest exporter of ornamental fish in Taiwan, to announce that the first green-fluorescent angelfish (Pterophyllum scalare) and convict cichlid (Cichlasoma nigrofasciatus) in the world have successfully been developed. The body colors of these two fish are a beautiful green fluorescent under blue light (as shown in the picture). With help from the Council of Agriculture and Fishery Agency, this industrial-academic cooperation received technical guidance from Academia Sinica and the “Office for the Promotion of Industrialization of Agricultural Biotechnology”. Then, through the screening and breeding undertaken by the technical team at Jy Lin Company, the beautiful new fish were cultivated which can be used for ornamental, scientific, and medical applications.

According to Yu-Ho Lin, Chairman of Jy Lin Company, these ornamental fish are aquaculture species with high economic value and great development potential. They are very suitable for development in Taiwan which is experiencing rising manpower costs and limited water resources at present. In addition to cats and dogs, ornamental fish are also very popular pets, due to the great variety of breeds and the various gorgeous colors. To develop the ornamental aquarium industry, two useful biotechnology tools of gene engineering and gene transfer can be utilized to change fish species and produce special genetic strains; for example, increasing or improving the appearance of the body color to make new kinds of tropical fish with a variety of hues. Through these techniques, we can greatly enhance a fish’s ornamental value and industrial competitiveness in international markets.

According to Dr. Jyh-Yih Chen of the Marine Research Station, Institute of Cellular and Organismic Biology, Academia Sinica, proper breeds and improvements are a crucial influence in terms of developing biotech pets with high economic value. After discussions with Jy Lin Company, he chose the common angelfish and convict cichlid to be the research subjects. He also suggested that Jy Lin Company speed up the cultivation of transparent strains of these two fishes, with the expectation that the implanted fluorescent protein genes would fully perform.

Three years ago, Academia Sinica began research on muscle promoters. Researchers recently found a new type of promoter with a whole-body muscle performance gene. A plasmid was also constructed, by means of a promoter connected to the green fluorescence protein gene and an antimicrobial peptide gene. The first convict cichlid implanted with the improved muscle-promoter fluorescence protein gene was born in the Marine Research Station, Institute of Cellular and Organismic Biology, Academia Sinica, on August 15, 2008. Through the technique of marker-assisted selection (MAS) provided by the Jy Lin Company, the molecular markers were applied to genetic breeding and improvement. To the present, the third generation (F3) has successfully been born, which has established a solid foundation for the industrialization of the achievements in such transgenic ornamental fish. “In the world, this is the first instance in which the fish of the Family Cichlidae have been implanted with the green fluorescent gene and have successfully passed it down to the next generation.” Undoubtedly, such research is a new milestone in terms of biotech pets. This is not only the first instance of fluorescent ornamental fish of the Family Cichlidae in the world, but also the largest fluorescent ornamental fish worldwide at the present stage! Such an achievement has initiated inspiring prospects of research on high-class ornamental fish.

Yu-Ho Lin pointed out that the common angelfish is a beautiful and elegant ornamental fish from the Amazon River. It was a global sensation when it was introduced to the international market in 1915. A pair of them might cost up to US$75. At that time, a new car cost only US$500. Because the common angelfish has graceful fin lines and a moderate personality, it still remains one of the most popular ornamental fish to this day. The transparent common angelfish implanted with the fluorescent protein gene is a breed exclusively cultivated by Jy Lin Company: its skin is transparent, while its internal organs can clearly be seen. Among the common angelfish from the Amazon River, the research personnel at Jy Lin Company searched for individuals with lighter skin color due to gene mutations, and bred them to produce later generations. Then, among the later generations, the ones with the lightest color were once again selected for breeding. After similar selection and breeding were repeatedly undertaken, individuals of the common angelfish with an almost-transparent skin color were finally cultivated.

Yu-Ho Lin said: The R&D team at Jy Lin Company adopted the transfer method via reproductive ovary electroporation, to transplant the external fluorescent protein gene into the transparent common angelfish’s ovaries. The first batch of F0 transgenic common angelfish (96 in total) were obtained in January 2008. After cultivating approximately 20,000 individuals, the research personnel were able to obtain transgenic fish that exhibited stable performance and passed the trait on to subsequent generations—the fluorescent common angelfish shows green fluorescent light from the inside out. Through two kinds of authentication via molecular biological techniques, the results were completely consistent, which proved that gene transfer was successful.

With technical guidance provided by the Marine Research Station, Institute of Cellular and Organismic Biology, Academia Sinica for many years, the Jy Lin Company has accumulated considerable experience in technical aspects of gene transfer in ornamental fish; these techniques are widely applied to many kinds of popular-selling fish internationally. At present, this industrial-academic cooperation is still actively ongoing, and aims to successfully apply a sterility technique to transgenic ornamental fish. In addition, by means of marker-assisted selection (MAS) in fish to analyze genetic variations and formation, the speed and efficiency of breeding fluorescent ornamental fish can be enhanced, so as to advance commercial mass production. In the meantime, Jy Lin Company also hopes as soon as possible to get these fish approved under the genetically modified organism (GMO) laws in various countries. In particular, they hope to gain approval under the Taiwanese GMO law.

When the Jy Lin Company carried out the research and developed the first green fluorescent common angelfish and convict cichlid in the world, many foreign biological museums actively invited the company through many channels to go there to exhibit these first green fluorescent species in the world.

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蔬菜對溫度日照條件的要求

蔬菜對溫度日照條件的要求
全日照  8個小時日照 瓜類、茄果類、豆類、山藥、豆薯(地瓜)。番茄、黃瓜、茄子、辣椒等喜溫中、強光性
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其次是根莖類,如:馬鈴薯、甜菜、胡蘿蔔、白蘿蔔、甘藷、山藥等等。至少需半日照,才能生長,芋頭雖喜歡全日照,但比其他蔬菜耐蔭。 
需要中等光照大白菜、甘藍、芥菜、蒜、洋蔥。 

長日性蔬菜白菜、甘藍、芥菜、蘿蔔、胡蘿蔔、芹菜、菠菜、萵苣、蠶豆、豌豆、大蔥、洋蔥。

短日性蔬菜豇豆、扁豆、莧菜、空心菜。         

中光性蔬菜黃瓜、番茄、茄子、辣椒、菜豆

菜豆

菜豆喜溫暖,不耐高溫和霜凍。菜豆種子發芽的適溫為20-30℃;在40℃以上的高溫和10℃以下的低溫,種子不易發芽。幼苗生長適宜氣溫為18-25℃。花芽分化的適宜氣溫為20-25℃,過高或過低溫度易出現發育不完全的花蕾、落花。

菜豆對光照強度的要求較高。在適宜溫度條件下,光照充足則植株生長健壯,莖的節間短而分枝多,開花結莢比較多,而且有利於根部對磷肥的吸收。當光照強度減弱時,植株易徒長,莖的節間長,分枝少,葉質薄,而且開花結莢數少,易落花落莢。

菜豆根系強大,能耐一定程度乾旱,但喜中度濕潤土壤條件,要求水分供應適中,不耐澇。生長期適宜土壤濕度為田間最大持水量的60%-70%,空氣相對濕度以80%為宜。開花結莢期對水分最敏感,此期土壤乾旱對開花結莢有不良影響,開花數、結莢數及莢內種子數減少。土壤水分過大時,下部葉片黃化,早脫落。空氣濕度過大會引起徒長、結莢不良。

菜豆具有深根性和根瘤菌,對土壤的要求不甚嚴格,但仍以土層深厚肥沃、排水良好的輕砂壤土或粘質壤土為好。土壤過於粘重、低溫、排水和通氣不良則生長不良,炭疽病重。菜豆喜中性至微酸性土壤,適宜的土壤pH為5-7.0,其中以州6.2-6.8最適宜。菜豆最忌連作,生產中應實行2-3年輪作。

菜豆生育過程中,主要吸收鉀和氮較多,還要吸收一定量的磷和鈣,才能良好發育。結莢期吸收磷鉀量較大。磷鉀肥對菜豆植株的生長發育、根瘤菌的發育、花芽分化、開花結莢和種子的發育等均有影響。缺乏磷肥,菜豆嫩莢和種子的品質和產量就會降低。缺鈣,幼葉葉片捲曲,葉緣失綠和生長點死亡。缺硼,則根係不發達,影響根瘤菌固氮,使花和豆莢發育不良。 耐陰半陰(大概3-4小時日照) 應選擇耐陰的蔬菜種植,如萵…

黑檸檬

黑檸檬
Dried lemons are actually limes and are used heavily in Persian Gulf and also Iranian cuisine where they add a strong bitter flavor in addition to sourness. They are made by boiling ripe limes in salt water, and then sun drying until the insides turn black. The outside color varies from tan to black. They are sold whole or ground.

Black Lime is a spice used in Middle Eastern dishes. It is made by boiling fresh lime in salt water and sun drying until the insides turn black. The outside color varies from tan to black. It is sold whole or ground.

黑檸檬實際上是使用萊姆,並且在波斯灣和伊朗料理中被大量使用,除了酸味外,它們還添加了強烈的苦味。它們是利用鹽水煮成熟萊姆,然後曬乾,直到內部變黑。外部顏色從棕褐色變化到黑色。他們可以整顆或切片販售。
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USE Black limes are usually used in legume, seafood or meat dishes. They are pierced, peeled or crushed before adding them to the dish. After cooking they become softer and edible. They can also be powdered and added to rice dishes. Powdered black lime is also used as an ingredient in Gulf-…

為何冰箱冷凍室非得是零下18度?

為何冰箱冷凍室非得是零下18度? 不少家庭的冰箱有led面板,可顯示冷藏室和冷凍室溫度。每次看到那個零下18℃,不少人,包括筆者在內就會禁不住提出一個小疑問:為什麼冷凍室溫度非得是零下18℃?最多零下1℃不就結冰了嗎?搞這麼低溫度實在是浪費電呢。

聰明如很多人是這樣推測的

百思不得其解,於是很多人,包括筆者在內就開始推測後面的機制了。冷凍室的零下18℃其實不費電,相反,它是節約電力的一個好措施。為何?

冰箱隔一段時間,內部溫度升高後,它就要啟動壓縮機,嗡嗡嗡的。頻繁啟動壓縮機不僅耗電,冰箱的壽命也會降低,還有就是很吵人。怎麼辦?簡單,先把冷凍室的溫度搞得低低的,比如零下18℃左右。


然後,冷凍室的冷氣往上走,來到冷藏室,如此,就能長時間保持冷藏室的溫度處於0到8℃以內了。

待冷凍室的冷氣散失過多,溫度升高到零下幾度時,再啟動冰箱的壓縮機把溫度再次降到零下18℃,如此,冰箱的啟動次數就變少了。

實際是這樣嗎?很遺憾,不是。

原因之一:不一樣的水

水到零度以下就結冰了,這是絕大多數人的認識。然而仔細一想,這不適用於冰箱的冷凍室。因為冷凍室存放的不是上百升礦泉水,而是各種各樣的食物。

食物中含有大量水這沒錯,但這些水同時含有大量的鹽、糖等物質。就像每1升海水中大約含有35克鹽,所以平均起來,要到零下1.33℃時海水才會結冰。

因此,要想把食物凍結,並不是溫度只要達到水的冰點就可以,得保證足夠低的溫度,食物中的水才能凍結,這很重要,因為食物中只要有液態水存在,這就等於是為各種細菌的繁殖提供了必備條件。

圖為牛肉薄片在不同溫度和不同時間內測得的牛肉中凍結水量的曲線。

當牛肉薄片的溫度為零下4℃時,只有70%的水分被凍結;溫度下降到零下9℃左右時,也還有3%的水分未凍結;即使牛肉薄片的溫度降低到零下18℃時,也不是100%的水分都被凍結住。

原因之二:嗜冷微生物

根據微生物對不同溫度的適應範圍,可將微生物分為三大類,嗜熱菌、嗜溫菌和嗜冷菌。在食物的冷藏和冷凍過程中,我們面對的「敵人」是嗜溫菌和嗜冷菌。

一般來說,能引起食物腐敗和食物致毒的嗜溫菌,在低於3 ℃情況下不產生毒素,當然,個別菌種例外。

而對於嗜冷菌,一般得在零下10 ℃到零下12 ℃時才會停止生長。

有的黴菌甚至要到零下15~零下18 ℃時才會停止生長。

瞧,我們以為,零下幾攝氏度後微生物就被殺死或停止繁殖了,但…