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142.
Silk fibers have been used in textiles for more than 5,000 years and as a suturing material for many centuries. The recent development of new applications for silks include drug delivery. An overview of this new field is provided, summarizing the development of emerging drug delivery applications which include silk-based nanomedicines and transdermal delivery systems We also highlight some of the challenges in developing silk-based drug delivery systems. 相似文献
143.
In the current study the savings of CO2 emissions due to the use of ground source heat pump (GSHP) systems was investigated in comparison to conventional heating systems. Based on a subsidy program for GSHP systems in southwest Germany, the regional, average, and total CO2 savings of 1105 installed GSHP systems were determined on a regional scale. The emitted CO2 per kWh of heating demand for the studied scenario resulted in 149 g CO2/kWh for GSHP using the German electricity mix and 65 g CO2/kWh using the regional electricity mix, which results in CO2 savings of 35% or 72%, respectively. Similar CO2 avoidances of GSHP systems were found in American and European studies ranging between 15% and 77% strongly depending on the supplied energy for the heat pumps and the efficiency of installation. The resulting CO2 savings for one installed GSHP unit in the present study therefore range between 1800 and 4000 kg per year. Nevertheless, the minimum average total annual CO2 savings of all installed GSHP systems due to the subsidy program amounted to 2000 tons per year. The maximum regional avoided additional CO2 emissions are primarily associated with the affluent suburbs of the most densely populated area in the region. In 2006 the total contribution of CO2 savings due to GSHP systems in Germany was only about 3.4% of the total renewable energies. However, continuously rising numbers of installed GSHP units and the increasing use of renewable electricity demonstrate that there is a fine opportunity to substantially avoid additional CO2 emissions associated with the provision of heating (and cooling) of buildings and other facilities. 相似文献
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Alexander Shakhov Christian Reichenbach Daria Kondrashova Philipp Zeigermann Dirk Mehlhorn Prof. Dirk Enke Dr. Rustem Valiullin 《化学,工程师,技术》2013,85(11):1734-1741
Mesoporous glasses – the leaching products of phase‐separated alkali borosilicate glasses – are widely used in fundamental research and practical applications. In this work, the option to control their internal mesopore structure by varying the conditions of microphase separation has been studied. Structure and transport characterization of a family of nanoporous glasses obtained under different conditions has been performed using a combination of several experimental techniques, including gas adsorption, nuclear magnetic resonance cryoporometry and diffusometry. 相似文献
147.
Portable mobile code is often executed by a host virtual machine using just‐in‐time compilation. In this context, the compilation time in the host virtual machine is critical. This compilation time can be reduced if optimizations are performed ahead‐of‐time before distribution of the mobile code. Unfortunately, the portable nature of mobile code limits ahead‐of‐time optimizations to those that are machine‐independent. This work examines the effect of machine‐independent optimizations on the performance of mobile code applications. All experiments use the SafeTSA Format, a mobile code format that is based on Static Single Assignment Form (SSA Form). The experiments, which are performed on both the PowerPC and IA32 architectures, indicate that the effects of performing classical machine‐independent optimizations are—in fact—quite machine‐dependent. Nevertheless, the results demonstrate that applying such optimizations in a mobile code system can be beneficial. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
148.
Hal Philipp 《电子设计技术》2009,16(4):62-63,68
现今社会上很多人都频繁地接触到触摸屏。这种装置最常见于PDA和手机等手持设备和售票终端系统等应用,其中大部分都基于电阻性技术。电阻性技术采用一个柔性外层,其压触固定内层时,会产生电信号,然后转换为X-Y坐标位置。此外,还有其它两种常用技术:表面声波(SAW)和电容感测技术,不过,一直以来,由于成本和构建的限制,这两种技术都仅用在公用信息服务应用(Kiosk applications)中。 相似文献
149.
OBJECTIVE AND IMPORTANCE: Symptomatic cerebral vasospasm can occur after resection of tumors in or adjacent to the basal cisterns, causing delayed neurological deterioration. This potentially treatable condition may go unrecognized. Delay in its recognition will adversely affect the outcome of the patients. There has been a few cases of vasospasm after tumoral resection reported in the literature, mostly in adults. We report a case of vasospasm after resection of a third nerve schwannoma in a pediatric patient. This is the youngest patient reported to date with vasospasm after resection of a brain tumor. CLINICAL PRESENTATION: A six years old girl presented with sudden onset diplopia. Radiological work-up revealed a third nerve mass. She underwent a craniotomy for resection of her mass. Pathological findings were consistent with a third nerve schwannoma. One week postoperatively, her mental status deteriorated. A CT scan revealed a diffuse hypodense area involving the right frontal and temporal lobes in the middle cerebral artery distribution as well as the midbrain. The absence of these findings on the MRI imaging performed on the first postoperative day made us evoke a vascular etiology. A cerebral angiogram was performed and revealed vasospasm in the right internal carotid artery and in the right middle and posterior cerebral arteries. Hyperdynamic hypervolemic hemodilutional therapy was instituted. CONCLUSION: Delayed clinical deterioration from vasospasm is a potentially reversible condition, if recognized early. A high index of suspicion should be maintained in case delayed clinical deterioration occurs after surgery of tumors in the basal cisterns. Cerebral angiography will confirm the diagnosis. Early institution of hyperdynamic hypervolemic hemodilutional therapy and angioplasty may reverse the deficit and improve outcome. 相似文献
150.
Antiatherosclerotic properties of water and alcoholic extracts of 20 types of high-species mushrooms were investigated by evaluation of intracellular cholesterol accumulation and 3H-thymidine inclusion into the cells of the human aortal intima in culture. The influence of a single intake of some mushroom species on antiatherosclerotic properties of the human sera was studied. It has been shown that Ganoderma lucidum and Lentinus edodes possess pronounced antiatherosclerotic properties. 相似文献