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61.
Lee A. Griffin Iaroslav Gaponenko Nazanin Bassiri-Gharb 《Advanced materials (Deerfield Beach, Fla.)》2020,32(38):2002425
Machine-learning techniques are more and more often applied to the analysis of complex behaviors in materials research. Frequently used to identify fundamental behaviors within large and multidimensional datasets, these techniques are strictly based on mathematical models. Thus, without inherent physical or chemical meaning or constraints, they are prone to biased interpretation. The interpretability of machine-learning results in materials science, specifically materials’ functionalities, can be vastly improved through physical insights and careful data handling. The use of techniques such as dimensional stacking can provide the much needed physical and chemical constraints, while proper understanding of the assumptions imposed by model parameters can help avoid overinterpretation. These concepts are illustrated by application to recently reported ferroelectric switching experiments in PbZr0.2Ti0.8O3 thin films. Through systematic analysis and introduction of physical constraints, it is argued that the behaviors present are not necessarily due to exotic mechanisms previously suggested, but rather well described by classical ferroelectric switching superimposed by non-ferroelectric phenomena, such as electrochemical deformation, electrostatic interactions, and/or charge injection. 相似文献
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Glioblastoma is the most common malignant primary brain tumor in adults and is almost invariably fatal. Despite our growing understanding of the various mechanisms underlying treatment failure, the standard-of-care therapy has not changed over the last two decades, signifying a great unmet need. The challenges of treating glioblastoma are many and include inadequate drug or agent delivery across the blood–brain barrier, abundant intra- and intertumoral heterogeneity, redundant signaling pathways, and an immunosuppressive microenvironment. Here, we review the innate and adaptive molecular mechanisms underlying glioblastoma’s treatment resistance, emphasizing the intrinsic challenges therapeutic interventions must overcome—namely, the blood–brain barrier, tumoral heterogeneity, and microenvironment—and the mechanisms of resistance to conventional treatments, targeted therapy, and immunotherapy. 相似文献
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Nazanin Rahimi Mohammad Mahdi Doroodmand Samad Sabbaghi Mohammad Hossein Sheikhi 《Materials science & engineering. C, Materials for biological applications》2013,33(6):3173-3179
Hydrogen evolution of multi-walled nanotube (MWCNT)/micro-hybrid polymer composite, decorated with Ni nanoparticles through electroless deposition process is studied by the electrochemical method. Cyclic voltammetry (CV) is utilized to clearly study the electrochemical hydrogen storage/evolution behavior of the composite through a potential window ranging from ? 1.60 to + 0.60 V (vs. Ag/AgCl). Hydrogen adsorption/desorption peaks are positioned at ? 1.52 and ? 0.05 V, respectively. Chronoamperometry is also applied to estimate active surface area (0.145 m2 g? 1) of the composite as well as the diffusion coefficient (3.4 × 10? 11 m2 s? 1) of adsorbed hydrogen process. According to the chrono-charge/discharge technique, the capacity of fabricated Ni-MWCNT/micro-hybrid composite is estimated to be 2.98 wt.% during charging for a certain time (40 min). 相似文献
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Specific link between high fructose uptake and cancer development and progression highlighted fructose transporters as potential means to achieve GLUT-mediated discrimination between normal and cancer cells. The gained expression of fructose-specific transporter GLUT5 in various cancers offers a possibility for developing cancer-specific imaging and bioactive agents. Herein, we explore the feasibility of delivering a bioactive agent through cancer-relevant fructose-specific transporter GLUT5. We employed specific targeting of GLUT5 by 2,5-anhydro-D-mannitol and investigated several drug conjugates for their ability to induce cancer-specific cytotoxicity. The proof-of-concept analysis was carried out for conjugates of chlorambucil (CLB) in GLUT5-positive breast cancer cells and normal breast cells. The cytotoxicity of conjugates was assessed over 24 h and 48 h, and significant dependence between cancer-selectivity and conjugate size was observed. The differences were found to relate to the loss of GLUT5-mediated uptake upon increased conjugate size and hydrophobicity. The findings provide information on the substrate tolerance of GLUT5 and highlight the importance of maintaining appropriate hydrophilicity for GLUT-mediated delivery. 相似文献
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In general, there is a wide range of literature covering the area of thermal comfort, but not a focused literature review of thermal comfort in hospitals has published yet. However, there has been no study on the direct effect of thermal comfort on health. The authors have found a reasonable amount of literature in thermal comfort in hospitals. This paper presents a literature review on thermal comfort in hospitals. From the review, the paper concludes that it is important to undertake original studies in the relationship between thermal comfort conditions and productivity for hospital staff. The study finally concluded that it is important to find some solutions to reconcile the different thermal comfort conditions required by different occupants in hospitals. These solutions could be used whenever patients and the attending caregivers have to stay in one room for a long time compulsorily. 相似文献
67.
Evelina Enqvist Dmitrij Ramanenka Paula A.A.P. Marques Jos Gracio Nazanin Emami 《Polymer Composites》2016,37(4):1128-1136
Ultra high molecular weight polyethylene (UHMWPE) composites reinforced with multiwalled carbon nanotubes (MWCNT) were produced using planetary ball milling. The aim was to develop a more wear resistant composite with improved mechanical properties to be used in stress bearing joints. The effect of manufacturing parameters such as the effect of ball milling time and rotational speed on the final composite was analyzed by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), particle size distribution, and contact angle measurements. Ball milling as a mixing technique for UHMWPE based composites is not a new approach but yet, the effect of time, rotational speed, loading of milling jar, and type of ball mill has not been reported properly for UHMWPE. Composites with 0.5 and 1.0 wt% UHMWPE/MWCNTs were manufactured with different rotational speed and mixing times. The results indicate that rotational speed rather than mixing time is important for dispersing MWCNTs using planetary ball milling. Tensile test showed a slight decrease for the MWCNT concentration of 1 wt% suggesting that this amount is the threshold for a satisfactory distribution of the fillers in the matrix. POLYM. COMPOS. 37:1128–1136, 2016. © 2014 Society of Plastics Engineers 相似文献
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Nejatian Mohammad Jonaidi-Jafari Nematollah Abbaszadeh Sepideh Saberian Hamed Darabzadeh Nazanin Ghanizadeh Ghader 《Food science and biotechnology》2019,28(2):405-412
Food Science and Biotechnology - In this study, the flow behavior and creep parameters of saffron desserts containing gum tragacanth combinations of three species were modeled by the mixture design... 相似文献
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We investigate the application of low-density parity-check (LDPC) codes in volume holographic memory (VHM) systems. We show that a carefully designed irregular LDPC code has a very good performance in VHM systems. We optimize high-rate LDPC codes for the nonuniform error pattern in holographic memories to reduce the bit error rate extensively. The prior knowledge of noise distribution is used for designing as well as decoding the LDPC codes. We show that these codes have a superior performance to that of Reed-Solomon (RS) codes and regular LDPC counterparts. Our simulation shows that we can increase the maximum storage capacity of holographic memories by more than 50 percent if we use irregular LDPC codes with soft-decision decoding instead of conventionally employed RS codes with hard-decision decoding. The performance of these LDPC codes is close to the information theoretic capacity. 相似文献
70.
Comparison of pregabalin with doxepin in the management of uremic pruritus: a randomized single blind clinical trial 下载免费PDF全文
Nazanin Foroutan Abbas Etminan Naemeh Nikvarz Mohadese Shojai Shahrokh Abadi 《Hemodialysis international. International Symposium on Home Hemodialysis》2017,21(1):63-71
Introduction: Pruritus is one of the frustrating skin manifestations of advanced renal failure. Many options have been used for the management of uremic pruritus (UP) such as pregabalin. There are some studies that reported beneficial effects of pregabalin in reducing UP; however, most of them did not have a comparator arm. Therefore, we designed this study to compare antipruritic effects of pregabalin with doxepin in the management of pruritus in hemodialysis patients. Methods: Seventy‐two patients suffering from UP were randomly assigned to receive pregabalin (50 mg every other day) or doxepin (10 mg per day) for 4 weeks. Severity of pruritus and its effect on quality of life were assessed by visual analog scale (VAS), 5‐D itch scale and dermatology life quality index (DLQI) at baseline and after 1 week, 2 weeks and 4 weeks of the treatment. Findings: Mean scores of the VAS decreased from 7.5± 1.4 and 7.1 ± 1.3 at baseline to 2.1 ± 2.6 and 4.2 ± 2.6 at the end of the study (P < 0.001) in the pregabalin and doxepin groups, respectively. Similarly, pregabalin significantly reduced mean scores of the 5‐D itch scale and the DLQI compared to doxepin. The most reported side effect in each group was somnolence which occurred in similar rates in the both groups. Discussion: Pregabalin was more effective than doxepin in reducing the severity of uremic pruritus and improving the quality of life of patients in this study, so we suggest that clinician can consider pregabalin prior to using antihistamine drugs in the management of severe itch in hemodialysis patients. 相似文献