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991.
Robert P. Reference to Marande Ronald P. Reference to Krahe Faisal K. Reference to Fadul 《Computers & Electrical Engineering》1999,25(6):493-500
This paper describes the development and implementation of a self-tuning microcontroller-based instrument for measuring different thicknesses of glass and glass substitutes. The instrument’s hardware was successfully tested in the laboratory on coated and uncoated glass under a variety of conditions. It is designed to provide high performance and high precision measuring capability to the system user. The obtained experimental data suggest that the proposed instrument surpasses existing techniques in its accuracy, reliability, simple operation, safety and measuring capability. 相似文献
992.
Mohamed Haider Amr Elsherbeny Valeria Pittal Valeria Consoli Maha Ali Alghamdi Zahid Hussain Ghalia Khoder Khaled Greish 《International journal of molecular sciences》2022,23(3)
Lung cancer (LC) is one of the leading causes of cancer occurrence and mortality worldwide. Treatment of patients with advanced and metastatic LC presents a significant challenge, as malignant cells use different mechanisms to resist chemotherapy. Drug resistance (DR) is a complex process that occurs due to a variety of genetic and acquired factors. Identifying the mechanisms underlying DR in LC patients and possible therapeutic alternatives for more efficient therapy is a central goal of LC research. Advances in nanotechnology resulted in the development of targeted and multifunctional nanoscale drug constructs. The possible modulation of the components of nanomedicine, their surface functionalization, and the encapsulation of various active therapeutics provide promising tools to bypass crucial biological barriers. These attributes enhance the delivery of multiple therapeutic agents directly to the tumor microenvironment (TME), resulting in reversal of LC resistance to anticancer treatment. This review provides a broad framework for understanding the different molecular mechanisms of DR in lung cancer, presents novel nanomedicine therapeutics aimed at improving the efficacy of treatment of various forms of resistant LC; outlines current challenges in using nanotechnology for reversing DR; and discusses the future directions for the clinical application of nanomedicine in the management of LC resistance. 相似文献
993.
An experimental programme is described, in which a number of thermo-analytical techniques, differential scanning calorimetry (DSC), thermogravimetry (TG and DTG) are applied to investigate the combustion of black powder. The primary aim has been to investigate, and determine qualitatively and quantitatively, the nature of the solid products of combustion. Additionally, standard analytical techniques were applied, to a chemical analysis of the solid products, resulting from the electric arcignition of a sample of black-powder, under ambient, open air conditions. The solid products formed 33% by weight of the unburned black powder, consisting of K2SO4 (15%), K2CO3 (11.5%) and small amounts of KNO3 and KNO2. The DSC, TG and DTG analyses suggest a mechanism for the combustion, based on phase changes and transition stages of sulfur and KNO3, and their interaction with charcoal. 相似文献
994.
Claudia Honisch Federica Torni Rohanah Hussain Paolo Ruzza Giuliano Siligardi 《International journal of molecular sciences》2022,23(6)
The tau protein, a soluble protein associated with microtubules, which is involved in the assembly and stabilization of cytoskeletal elements, was found to form neurofibrillary tangles in different neurodegenerative diseases. Insoluble tau aggregates were observed to be organized in paired helical filaments (PHFs) and straight filaments (SFs). Recently, two small sequences (306–311 and 275–280) in the microtubule-binding region (MTBR), named PHF6 and PHF6*, respectively, were found to be essential for tau aggregation. Since a possible therapeutic approach consists of impairing amyloid formation either by stabilizing the native proteins or reducing the level of amyloid precursors, here we use synchrotron radiation circular dichroism (SRCD) at Diamond B23 beamline to evaluate the inhibitory effects of two small molecules, trehalose and ceftriaxone, against the aggregation of a small peptide containing the PHF6* sequence. Our results indicate that both these molecules, ceftriaxone and trehalose, increased the stability of the peptide toward aggregation, in particular that induced by heparin. With trehalose being present in many fruits, vegetables, algae and processed foods, these results support the need to investigate whether a diet richer in trehalose might exert a protective effect toward pathologies linked to protein misfolding. 相似文献
995.
In this paper we propose a MAC called “Neighbor Initiated Approach for avoiding Deaf and Hidden node problems in directional MAC protocol for Ad Hoc networks”, which takes advantage of the multi beam smart antennas. Through the antenna, a node can simultaneously transmit/receive a packet to/from all the directions around it. Thus the antenna switches itself in transmission and reception mode. In our scheme all transmission and reception will be directional. We discussed the hidden and deaf node problems with directional MAC and proposed the scheme to overcome those shortcomings. Our scheme has been inspired by the IEEE 802.11, which includes a new scheme to inform its neighbors who was deaf due to other communication. Moreover, the simultaneous transmission of the RTS/CTS through it’s all beams prevent the hidden node problem. In our scheme the idle nodes stay in reception mode for sensing the channel through its M non overlapping beams, as a substitute of omnidirectional antenna. It prevents the hidden node problem due to asymmetry in gain. We have simulated our scheme by OPNET 16.0, and compared our results with CDR MAC, DMAC and IEEE 802.11 protocols. Our results show that NIADH performs better than that of the existing protocols in majority of the scenarios. 相似文献
996.
997.
Antioxidant and antitumour activities of exopolysaccharide from liquid‐cultured Grifola frondosa by chemical modification
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Wenna Zhang Yongming Lu Yaping Zhang Qiuying Ding Sajid Hussain Qingxi Wu Wenjuan Pan Yan Chen 《International Journal of Food Science & Technology》2016,51(4):1055-1061
Grifola frondosa is a popular edible mushroom for its tasty flavour and can be used as a dietary supplement for its functional substances. In this study, an exopolysaccharide (EPS), purified from the submerged culture of G. frondosa, was chemically modified to obtain its carboxymethylated (CM‐EPS) and selenising derivatives (Se‐EPS). The chemical characteristics of these polysaccharides were determined based on high‐performance liquid chromatography (HPLC) and infrared analysis (IR). The antioxidant and antitumour activities of EPS and its derivatives were further investigated, respectively. The results showed that the antioxidant capacity of CM‐EPS and Se‐EPS were much better than that of EPS. Moreover, the Se‐EPS could significantly inhibit the proliferation of Hela cells compared with EPS. This study demonstrated that the carboxymethylation and selenylation played a great influence on enhancing the antioxidant and antitumour activities of exopolysaccharides from G. frondosa. 相似文献
998.
Here, more than 100 years of incumbency reports on officers of the irrigation bureaucracy of Punjab, Pakistan, are presented and analyzed. The data highlight how representation changed before and after partition within the irrigation bureaucracy. The data show that the irrigation bureaucracy increased through staffing its representation of local communities and is in its appointments responsive to elected representatives. Therefore, it is argued that empowerment of the local community can be achieved without irrigation management transfer but through the irrigation bureaucracy itself. 相似文献
999.
1000.