你是家庭和朋友的IT人吗？

当今,支持的费用是IT部门最大的开支。我们都在想方设法计量和减少这种开销。但是有一种IT支持的费用没有列在预算或收支平衡表上,那就是我们花费在支持朋友和家庭成员解决IT问题上的时间。我们将它称之为＂个人IT＂。     

Impact of Preferential P-Diffusion Along the Grain Boundaries on Fine-Grained Polysilicon Solar Cells

Thin-film polysilicon solar cells are a promising low-cost alternative for bulk silicon solar cells due to their reduced material thickness. Recently, we showed that the use of an amorphous silicon/polycrystalline silicon heterojunction emitter instead of a diffused homojunction emitter led to a boost in the open-circuit voltage by 90 mV. Now, we present a full evidence that shows that this improvement is related to the absence of dopant smearing along the grain boundaries. By using scanning spreading resistance microscopy, we found an enlargement of the junction area by a factor of five in case of a homojunction. The tips of the dopant spikes represent lowly doped areas with an enhanced recombination.     

Considerations and strategies behind the design and construction requirements of the Istanbul Strait immersed tunnel

This being a design-build project, the challenge faced during preparations of the Employer’s requirements for design and construction of the Istanbul Strait immersed tunnel was to give the contractor as much freedom as possible and yet specify enough so that the Employer obtained the required facility. When completed, this will be a world-class facility. This paper discusses on a strategic level many of the aspects to be presented by the author in two papers in later sessions of the day. Unusual features of this crossing include the deepest ever immersed tunnel crossing, extra waterproofing requirements, strong currents with bi-directional flow, close proximity of the North Anatolian Fault which is predicted to have a major seismic event during the life of the tunnel, and the method of connecting the adjacent bored tunnels to the immersed tunnel. Safety during tunnel construction and operation has been paramount, and resulted in changes to contract packaging and extra requirements. Other challenges discussed include fish migration, control of an international waterway, environmental issues and ensuring the stability of the soft soils during a seismic event.     

Atomic force microscopic analysis of hydrogen peroxide bleached kraft northern black spruce fibres

Hydrogen peroxide is a potent, relatively inexpensive oxidant that chemically degrades chromophoric components in pulps and textiles. Oxidation of cellulose is a byproduct of this process step that decreases the tensile strength of individual fibres. The residence time of pulp in the bleaching reactor must be optimized to achieve the desired brightness and minimizing fibre degradation. To evaluate the impact of peroxide bleaching at the microfibrillar level, a single black spruce tree was chosen and kraft pulped. Peroxide bleaching was conducted via benchtop polyethylene bag bleaching in a temperature-controlled waterbath. Atomic force microscopy (AFM) topographical images acquired before and after the bleaching step show dramatic changes in fibre structure consistent with delignification and defects in the surface topography. This was further verified by X-ray work at Brookhaven National Laboratory, NY, U.S.A.     

Chitosan particles agglomerated scaffolds for cartilage and osteochondral tissue engineering approaches with adipose tissue derived stem cells

In the XML file of the original article, H. Redl’s affiliation is incorrect. It is listed correctly in both the paper and PDF versions of the article, and can be found below: The online version of the original article can be found at     

Mammalian Rh/T2/S-glycoprotein ribonuclease family genes: cloning of a human member located in a region of chromosome 6 (6q27) frequently deleted in human malignancies

OBJECTIVE: To implement a low-cost system of transmitting high-quality digital photographs of mutilating extremity injuries using the speed of the Internet. DESIGN: A high-resolution digital camera and simple hardware and software platform are used to take and transmit images via electronic mail. The images are received within minutes by the consultant, and an assessment can be made. RESULTS: A low-cost and high-quality system can easily be implemented. Images can be seen by consultants only a few minutes after they are obtained. The quality of the reproductions is excellent, and they are handled exactly as other photographs. CONCLUSION: This technique can be widely applicable and inexpensive to initiate in any emergency room. It allows rapid assessment of extremity injuries and x-ray images by expert consultants, who can then evaluate the replantation or revascularization potential of extremity trauma cases. This can eliminate unnecessary and often expensive transfer of patients who are not candidates for replantation.     

Detection of human papillomavirus gene sequences in laryngeal tumors and premalignant changes by polymerase chain reaction

Human papillomavirus gene sequences have been detected in a number of malignant and benign tumours. Non-oncogenic types 6 and 11 are etiological factors of benign mucosal tumours. Types 16 and 18 can be detected in malignancies most often but their role in the etiopathogenesis of cancers is still unclear. In our study we examined formalin-fixed and paraffin-embedded archive laryngeal tissues containing squamous cell carcinoma, papilloma and precancerous lesions for the presence of human papillomavirus genes. As a control we also examined tissues harbouring laryngeal nodules which represented the normal larynx in our study. After DNA preparation from the paraffin blocks we performed polymerase chain reaction to detect the DNA of human papillomavirus types 6, 11, 16 and 18. In the squamous cell carcinomas, papillomas and precancerous lesions the presence of human papillomavirus gene sequences was significantly higher than in the control group. To verify the integrity of DNA we also amplified a sequence deriving from the cellular beta-globin gene. Based on the 100% positivity for this gene we declare that the combination of our DNA preparation and polymerase chain reaction is a reliable method for detecting DNA sequences from formalin-fixed and paraffin-embedded tissues.