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排序方式: 共有892条查询结果,搜索用时 15 毫秒
31.
Xianrui Xie Yujie Chen Xiaoyu Wang Xiaoqing Xu Yihong Shen Atta ur Rehman Khan Ali Aldalbahi Allison E.Fetz Gary L.Bowlin Mohamed El-Newehy Xiumei Mo 《材料科学技术学报》2020,(24):243-261
Tissue engineering is an interdisciplinary field that integrates medical,biological,and engineering exper-tise to restore or regenerate the functionality of hea... 相似文献
32.
Emma P. Bullock Allison L. Roxburgh Patricia S. Moyer-Packenham Elif Bektas Joseph S. Webster Kathleen A. Bullock 《Journal of Computer Assisted Learning》2021,37(2):557-586
This study focused on an examination of how type, quality and children's awareness of design features in digital math games, along with an awareness of the mathematics goals of the game, were related to learning outcomes. We conducted a parallel conversion mixed methods study with 45 students in Grades 3 and 4 (ages 9–10). Students participated in clinical interviews using three digital math games. The results suggest a moderated mediation relationship in which the quality of the design features moderated the mediating impact of children's awareness of the game's design features, specifically when the child was aware of the mathematics content learning goal (MCLG) of the game. These findings show how important it is that design features are of high quality in a digital math game, and how this is intertwined with children's awareness of the features and the MCLG. When these variables intertwined in just the right way, the interactions between the children and the digital math game afforded mathematical learning growth. 相似文献
33.
Gink N. Yang Xanthe L. Strudwick Claudine S. Bonder Zlatko Kopecki Allison J. Cowin 《International journal of molecular sciences》2021,22(24)
Cutaneous squamous cell carcinoma (cSCC) accounts for 25% of cutaneous malignancies diagnosed in Caucasian populations. Surgical removal in combination with radiation and chemotherapy are effective treatments for cSCC. Nevertheless, the aggressive metastatic forms of cSCC still have a relatively poor patient outcome. Studies have linked actin cytoskeletal dynamics and the Wnt/β-catenin signaling pathway as important modulators of cSCC pathogenesis. Previous studies have also shown that the actin-remodeling protein Flightless (Flii) is a negative regulator of cSCC. The aim of this study was to investigate if the functional effects of Flii on cSCC involve the Wnt/β-catenin signaling pathway. Flii knockdown was performed using siRNA in a human late stage aggressive metastatic cSCC cell line (MET-1) alongside analysis of Flii genetic murine models of 3-methylcholanthrene induced cSCC. Flii was increased in a MET-1 cSCC cell line and reducing Flii expression led to fewer PCNA positive cells and a concomitant reduction in cellular proliferation and symmetrical division. Knockdown of Flii led to decreased β-catenin and a decrease in the expression of the downstream effector of β-catenin signaling protein SOX9. 3-Methylcholanthrene (MCA)-induced cSCC in Flii overexpressing mice showed increased markers of cancer metastasis including talin and keratin-14 and a significant increase in SOX9 alongside a reduction in Flii associated protein (Flap-1). Taken together, this study demonstrates a role for Flii in regulating proteins involved in cSCC proliferation and tumor progression and suggests a potential role for Flii in aggressive metastatic cSCC. 相似文献
34.
Aleksandra Kaliszewska Joseph Allison Matteo Martini Natalia Arias 《International journal of molecular sciences》2021,22(7)
Aging is inevitable and it is one of the major contributors to cognitive decline. However, the mechanisms underlying age-related cognitive decline are still the object of extensive research. At the biological level, it is unknown how the aging brain is subjected to progressive oxidative stress and neuroinflammation which determine, among others, mitochondrial dysfunction. The link between mitochondrial dysfunction and cognitive impairment is becoming ever more clear by the presence of significant neurological disturbances in human mitochondrial diseases. Possibly, the most important lifestyle factor determining mitochondrial functioning is nutrition. Therefore, with the present work, we review the latest findings disclosing a link between nutrition, mitochondrial functioning and cognition, and pave new ways to counteract cognitive decline in late adulthood through diet. 相似文献
35.
Jon R Saunders Heather Allison Chloe E James Alan J McCarthy Richard Sharp 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2001,76(7):662-666
Bacteriophages as accessory genetic elements play a crucial role in the dissemination of genes and the promotion of genetic diversity within bacterial populations. Such horizontal transfer of DNA is critical in the emergence of new pathogenic organisms, through the dissemination of genes encoding virulence factors such as toxins, adhesins and agressins. Phages can transfer genes that are not necessary for bacteriophage persistence and are generally recognised by their ability to convert their host bacteria to new phenotypes. This phenomenon is known as phage conversion. If such converting genes encode for virulence factors, the consequences of phage infection may include increased virulence of the host bacteria, and the conversion of a non‐pathogenic strain to a potentially dangerous pathogen. A number of virulence factors in bacteria causing diseases in plants, animals and humans are encoded by converting phages, the vast majority of which are temperate as opposed to lytic in nature. © 2001 Society of Chemical Industry 相似文献
36.
Approximately twelve years ago the first double-diffused silicon transistor was offered to the marketplace. These first transistors sold for $70.00. Today it is possible to purchase an integrated memory circuit with several thousand transistors plus several thousand resistors and diodes for less the original selling price of this first transistor. 相似文献
37.
A biomass recovery method was developed to monitor UV disinfection efficacy using adenosine triphosphate (ATP). Typically, disinfection monitoring at wastewater treatment facilities (WWTFs) involves quantifying fecal and total coliforms or colony forming units, the results of which take a minimum of 24 h to produce. ATP quantification immediately before and after UV treatment, which takes only minutes, shows little reduction and often an increase in the microbial population since UV irradiation results in cells that are viable (i.e., still producing ATP) but not culturable. To overcome this, our biomass recovery method incorporates an incubation step to encourage life cycling of microbes. Average log reductions in cellular ATP (cATP) were found to be ?0.28 ± 0.19, ?0.011 ± 0.153, ?0.17 ± 0.32, and 0.065 ± 0.074 using direct ATP measurements on UV-treated samples from WWTFs A, B, C, and D, respectively, while those using the recovery method were correspondingly 0.17 ± 0.34, 1.8 ± 0.8, 0.20 ± 0.35, and 0.72 ± 0.26. The response of the biomass recovery-ATP method indicated a significant direct correlation to the microbial population reduction observed in heterotrophic plate count (HPC) and Colilert® methods using both pure Escherichia coli culture and secondary municipal wastewater effluent. 相似文献
38.
G. G. Wright A. R. Sibbald J. S. Allison 《International journal of remote sensing》2013,34(11):2319-2336
In this paper, high resolution, remotely-sensed data are investigated as a source of management information for moorland vegetation communities on a hypothetical farm in a marginal farming area of Scotland. A hybrid technique for vegetation mapping is adopted. This involves unsupervised machine classification of spectral variation in digitally enhanced air photographs and satellite imagery, together with visual interpretation of the imagery in both the laboratory and the field. This technique enables relative estimates of annual gross biomass production, for a range of vegetation types, to be obtained. The data are integrated into a simple heather moorland management model (HMMM), to produce potential sheep-stocking capacities under a range of management scenarios, the possible financial implications of these scenarios are also assessed. 相似文献
39.
Cyberbullying is a newer variation of bullying that utilizes technology to harass. This study investigated the psychological symptomology, suicidal behaviors, aggressive tendencies, and illegal behaviors of college cyberbullies. Sixty cyberbullies and 19 cyberbully/victims (participants who cyberbullied and were victims of cyberbullying) scored higher in psychological symptoms of depression, hostility, interpersonal sensitivity, paranoia, phobic anxiety, and psychoticism than participants who were uninvolved with cyberbullying. The cyberbullies also endorsed more suicidal behaviors and scored higher in aggression. The cyberbully/victims engaged in more violent and drug crimes than cyberbullies and controls. These findings indicate perpetrators of cyberbullying have more psychological distress, aggressive tendencies, and engage in more illegal behaviors than those who do not cyberbully. This is the first study to show the distress cyberbullies are experiencing. 相似文献
40.
Allison Luong 《程序员》2007,(5):10-11
目前,中国正逐渐成为西方寻找外包开发游戏公司的一片新热土,Pearl Research认为中国市场上存在的大量劳动力,相对较低的劳务成本,大批的游戏玩家以及完善的设施都是形成这种态势的重要原因。通过向中国开发公司外包,仅就游戏美工一项,往往就可以帮助西方公司节约20%以上的开发成本,在次时代游戏开发成本超越400万美元的今天,开发成本的减少将直接提升公司的毛利率,并对游戏产品的获利与否产生直接影响。 相似文献