Hari-hari tanpa istirahat…..

Dah tiga hari ini aq ga sempet istirahat dengan tenang. Malem jaga warnet, paginya langsung ke lab ngerjain proyeknya dosen sampe sore. Sore pulang mandi bentar, habis itu ke lab lagi sampe jam 23.30 and ga sempet pulang tapi langsung ke warnet……. Duh capeknya……….

Jumlah Blogku Berapa Yach……….????

Kalo diinget2 semenjak bisa buat blog sendiri, kayaknya dah banyak bngt. Sampe2 temenku ada yang nanya…

“Emang buat apa bikin blog banyak bngt?”

Trus aku jawab, “Biar terkenal … He.. he.. “

Yang jelas aku enjoy aja bikin blog banyak2. Cos aku dah tau caranya memanfaatkan sedikit waktu tuk menghasilkan uang tambahan. Klo ga percay, liat aja cerita orang2 yang dah jd jutawan gara2 ngeblog. Cos selain google Adsense, banyak juga yang memberikan uang buat kita klo kita masang bannernya. Ato situs2 luar yang mo ngiklan di situs2 penyedia layanan advertising.

Ya… walopun blm jd jutawan, setidaknya accoun adsense q dah ada isinya He… he…

Oke dech…. buat yg blom manfaatin bognya, buruandech daftar di Adsense, Bidvertiser, Obeus, wigdetbuks, Adbrite, And banyk lg situs2 yang nyediain fasilitas pay per click. bahkan kemaren aku dapat info klo Friendster juga ada yg bisa menghasilkan dollar. So cari tau aja yah………

Ngomong2 soal jumlah blogku, aku sebutin aja semua :

1. jurnalilmiah.blogspot.com
2. kurnia25.blogspot.com
3. laptopworld21.blogspot.com
4. mypublisher.blogsome.com
5. publisher.blogsome.com

Ah… pokoknya banyak dech. Cos klo diinget2 skrg aku ga inget smua.

The geomicrobiology of gold

Subject Category: Geomicrobiology and microbial contributions to geochemical cycles

The ISME Journal (2007) 1, 567–584; doi:10.1038/ismej.2007.75; published online 20 September 2007

Frank Reith¹, Maggy F Lengke², Donna Falconer³, David Craw³ and Gordon Southam⁴

1. ¹School of Earth and Environmental Sciences, The University of Adelaide, CSIRO Land and Water, Waite Laboratories, Urrbrae, South Australia, Australia
2. ²Geomega Inc., Boulder, CO, USA
3. ³Department of Geology, University of Otago, Dunedin, New Zealand
4. ⁴Department of Earth Sciences, The University of Western Ontario, London, Ontario, Canada

Correspondence: F Reith, School of Earth and Environmental Sciences, The University of Adelaide, CSIRO Land and Water, Waite Laboratories, Waite Road, Glen Osmond, Urrbrae, Adelaide South Australia 5064, Australia. E-mail: Frank.Reith@csiro.au

Abstract

Microorganisms capable of actively solubilizing and precipitating gold appear to play a larger role in the biogeochemical cycling of gold than previously believed. Recent research suggests that bacteria and archaea are involved in every step of the biogeochemical cycle of gold, from the formation of primary mineralization in hydrothermal and deep subsurface systems to its solubilization, dispersion and re-concentration as secondary gold under surface conditions. Enzymatically catalysed precipitation of gold has been observed in thermophilic and hyperthermophilic bacteria and archaea (for example, Thermotoga maritime, Pyrobaculum islandicum), and their activity led to the formation of gold- and silver-bearing sinters in New Zealand’s hot spring systems. Sulphate-reducing bacteria (SRB), for example, Desulfovibrio sp., may be involved in the formation of gold-bearing sulphide minerals in deep subsurface environments; over geological timescales this may contribute to the formation of economic deposits. Iron- and sulphur-oxidizing bacteria (for example, Acidothiobacillus ferrooxidans, A. thiooxidans) are known to breakdown gold-hosting sulphide minerals in zones of primary mineralization, and release associated gold in the process. These and other bacteria (for example, actinobacteria) produce thiosulphate, which is known to oxidize gold and form stable, transportable complexes. Other microbial processes, for example, excretion of amino acids and cyanide, may control gold solubilization in auriferous top- and rhizosphere soils. A number of bacteria and archaea are capable of actively catalysing the precipitation of toxic gold(I/III) complexes. Reductive precipitation of these complexes may improve survival rates of bacterial populations that are capable of (1) detoxifying the immediate cell environment by detecting, excreting and reducing gold complexes, possibly using P-type ATPase efflux pumps as well as membrane vesicles (for example, Salmonella enterica, Cupriavidus (Ralstonia) metallidurans, Plectonema boryanum); (2) gaining metabolic energy by utilizing gold-complexing ligands (for example, thiosulphate by A. ferrooxidans) or (3) using gold as metal centre in enzymes (Micrococcus luteus). C. metallidurans containing biofilms were detected on gold grains from two Australian sites, indicating that gold bioaccumulation may lead to gold biomineralization by forming secondary ‘bacterioform’ gold. Formation of secondary octahedral gold crystals from gold(III) chloride solution, was promoted by a cyanobacterium (P. boryanum) via an amorphous gold(I) sulphide intermediate. ‘Bacterioform’ gold and secondary gold crystals are common in quartz pebble conglomerates (QPC), where they are often associated with bituminous organic matter possibly derived from cyanobacteria. This may suggest that cyanobacteria have played a role in the formation of the Witwatersrand QPC, the world’s largest gold deposit.

 

Keywords:

microorganisms, gold, geomicrobiology, solubilization, bioaccumulation, biomineralization

Cinta Itu………..

Sobat muda muslim, jumpa lagi ama STUDIA ye. Edisi pekan ini, masih tentang cinta. Moga aja nggak bosen, dan nggak pernah bosen. Gimana pun juga, tema cinta tuh emang everlasting alias kagak ada matinye. Nah, di edisi ini, sengaja dan terpaksa STUDIA bahas soal cinta lagi. Tapi, semoga aja ini agak lain. Sebenarnya tema cinta yang akan ditulis di buletin ini udah banyak berseliweran di dunia maya, tapi STUDIA akan berusaha memodifikasinya, mempermaknya, dan men-syarah-nya dengan sudut pandang Islam yang lebih dalem, dan tentu dengan gaya STUDIA dong ya. Makasih buat yang udah nulis pertama kali artikel ini di internet. Penulis asli tulisan ini jadi nggak ketahuan karena tulisan tersebut udah berbiak di banyak situs dengan sumber “unknown”.

Oya, ada beberapa penjelasan tentang cinta. Kamu kayaknya nggak ada salahnya kalo tahu soal ini. Oke, biar nggak makan banyak tempat dan ngebusa mulu di prolognya, kita jembrengin dan pretelin satu per satu tentang karakter cinta ini. Siap ya. Go!

Cinta=perasaan sekaligus akal sehat