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261.
A series of surfactants derived from l-Proline, the free amine esters, the ester hydrochlorides and the quaternary ammonium compounds with varying chain lengths (C8–C14) were synthesised. The physicochemical and biological properties were determined in both single and sodium dodecyl sulphate (SDS) mixed systems with a view of enhancing the properties of the individual surfactants as potential ingredients in detergent formulations. The mode of action of the proline surfactants were investigated by their ability to form mixed micelles with the phospholipid 1,2-dimyristoyl-sn-glycero-3-phosphatidylcholine (DMPC). The presence of a quaternary ammonium moiety and an increase in alkyl chain length were found to enhance the antibacterial activity of the proline QUAT derivatives. The SDS-C14 QUAT mixed system displayed good antibacterial activity with optimum activity at mole fractions αQUAT: 0.4 and 0.6. The antibacterial activity of the mixed system was found to be governed by the monomers rather than the micelles. The SDS-C14 QUAT mixed system also showed moderate irritancy which makes them potential candidates as detergents.  相似文献   
262.
Für viele heutige IT-Dienste w?re eine st?rkere Authentifizierung als die mit Nutzername und Passwort wünschenswert. Insbesondere für sicherheitskritische Prozesse, wie das Zurücksetzen von Passw?rtern, sind bestehende L?sungen oft unbefriedigend. Der neue Personalausweis (nPA) stellt mit seiner eID-Funktion die M?glichkeit für eine starke Authentisierung bereit. Jedoch stehen dem erreichbaren Sicherheitsgewinn nicht unerhebliche Kosten gegenüber, die pro Dienstanbieter aufgebracht werden müssen, um die eID-Funktion zu nutzen. Wir zeigen mit dem Konzept Auth2(nPA), wie eine Zweifaktorauthentisierung mit dem nPA von mehreren Einrichtungen gemeinsam genutzt werden kann. Um für diesen Dienst ein Berechtigungszertifikat zu erhalten, realisiert das Auth2(nPA)-Konzept ein vergleichbar hohes Datenschutzniveau wie die generische eID-L?sung mit getrennten Dienstanbietern.  相似文献   
263.
Pancreatic adenocarcinoma displays a variety of molecular changes that evolve exponentially with time and lead cancer cells not only to survive, but also to invade the surrounding tissues and metastasise to distant sites. These changes include: genetic alterations in oncogenes and cancer suppressor genes; changes in the cell cycle and pathways leading to apoptosis; and also changes in epithelial to mesenchymal transition. The most common alterations involve the epidermal growth factor receptor (EGFR) gene, the HER2 gene, and the K-ras gene. In particular, the loss of function of tumor-suppressor genes has been documented in this tumor, especially in CDKN2a, p53, DPC4 and BRCA2 genes. However, other molecular events involved in pancreatic adenocarcinoma pathogenesis contribute to its development and maintenance, specifically epigenetic events. In fact, key tumor suppressors that are well established to play a role in pancreatic adenocarcinoma may be altered through hypermethylation, and oncogenes can be upregulated secondary to permissive histone modifications. Indeed, factors involved in tumor invasiveness can be aberrantly expressed through dysregulated microRNAs. This review summarizes current knowledge of pancreatic carcinogenesis from its initiation within a normal cell until the time that it has disseminated to distant organs. In this scenario, highlighting these molecular alterations could provide new clinical tools for early diagnosis and new effective therapies for this malignancy.  相似文献   
264.
Reports an error in "Interpersonal victimization patterns and psychopathology among Latino women: Results from the SALAS study" by Carlos A. Cuevas, Chiara Sabina and Emilie H. Picard (Psychological Trauma: Theory, Research, Practice, and Policy, 2010[Dec], Vol 2[4], 296-306). There were citation errors in the last sentence of the first column of text on page 9, and a reference was omitted from the reference list. The sentence should have read: “This result is consistent with other work that has found support for the anxious and dissociative reaction associated with trauma among Latinos and how it may relate to “ataque de nervios” (Hinton, Chong, Pollack, Barlow, & McNally, 2008; Lewis-Fernandez et al., 2002; Schechter et al., 2000; Tolin, Robinson, Gaztambide, Horowitz, & Blank, 2007). (The following abstract of the original article appeared in record 2010-19221-001.) Research on the victimization of Latino women and the subsequent psychological impact has been limited by focusing on individual forms of victimization, primarily partner violence or sexual assault. Another deficiency includes mainly using convenience and/or geographically restricted samples, which impacts the generalizability of the results. To overcome these research limitations, the Sexual Assault Among Latinas (SALAS) study aimed to evaluate the broader scope of victimization among Latino women. The study surveyed a national sample of 2,000 Latino women using random digit dial methodology. Women were asked about various forms of victimization in childhood and adulthood including physical assaults, sexual assaults, stalking, threats, and witnessed violence, as well as psychological symptomatology including depression, anxiety, anger, and dissociation. This analysis found that victimized women were more likely to experience some form of polyvictimization and/or revictimization throughout their lives, with only 36% of victimized women experiencing one form of victimization in childhood or adulthood alone. Furthermore, multiple victimization experiences significantly increased the proportion of women who experienced psychological distress symptoms in the clinical range. For almost all evaluated symptoms, the multiple forms of victimization or varying victimization patterns significantly predicted clinical levels of psychological distress over any specific form or single incident of victimization. The results suggest that victimized Latino women experience multiple forms of victimization and that the evaluation of a broader spectrum of victimization better accounts for pathological symptomatology. Clinical implications for Latino women and future research directions are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
265.
Effects of intervention with the Oregon model of Parent Management Training (PMTO?) on marital relationship processes and marital satisfaction in recently married biological mother and stepfather couples were examined. Sixty-seven of the 110 participating families were randomly assigned to PMTO, and 43 families to a non-intervention condition. Intervention had reliable positive indirect effects on marital relationship processes 24 months after baseline which in turn were associated with higher marital satisfaction. These indirect effects were mediated by the impact of PMTO on parenting practices 6 months after baseline. Enhanced parenting practices resulting from PMTO prevented escalation of subsequent child behavior problems at school. Consistent with a family systems perspective and research on challenges to marital quality in stepfamilies, improved co-parenting practices were associated with enhanced marital relationship skills and marital satisfaction as well as with prevention of child behavior problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
266.
This paper presents an integrated method that assesses the socio-economic impact of establishing renewable energy on a regional scale, in particular on the creation of jobs. The method proposed is based on the collection, critical analysis and presentation of the results obtained using primary information sources considering the jobs created as the most direct measure of the socio-economic potential of renewable energy sources. Its design includes contributions extracted from a prior analysis of the existing assessment methods, to lessen the uncertainty of the job ratios often used in these types of analysis. The integrated method implemented has been applied to the autonomous community of Aragon (Spain) as a pilot case, through which the method has been tested and the indicators selected to analyse the socio-economic impact of renewable energy sources on the jobs created, the quality of the jobs and other factors related to the socio-economic development of a territory: technological development, per capita income, territorial development and human capital.  相似文献   
267.
268.
1. The aim of this study was to investigate, by use of spectral analysis, (1) the blood pressure (BP) variability changes in the conscious rat during blockade of nitric oxide (NO) synthesis by the L-arginine analogue NG-nitro-L-arginine methyl ester (L-NAME); (2) the involvement of the renin-angiotensin system in these modifications, by use of the angiotensin II AT1-receptor antagonist losartan. 2. Blockade of NO synthesis was achieved by infusion for 1 h of a low-dose (10 micrograms kg-1 min-1, i.v., n = 10) and high-dose (100 micrograms kg-1 min-1, i.v., n = 10) of L-NAME. The same treatment was applied in two further groups (2 x n = 10) after a bolus dose of losartan (10 mg kg-1, i.v.). 3. Thirty minutes after the start of the infusion of low-dose L-NAME, systolic BP (SBP) increased (+10 +/- 3 mmHg, P < 0.01), with the effect being more pronounced 5 min after the end of L-NAME administration (+20 +/- 4 mmHg, P < 0.001). With high-dose L-NAME, SBP increased immediately (5 min: +8 +/- 2 mmHg, P < 0.05) and reached a maximum after 40 min (+53 +/- 4 mmHg, P < 0.001); a bradycardia was observed (60 min: -44 +/- 13 beats min-1, P < 0.01). 4. Low-dose L-NAME increased the low-frequency component (LF: 0.02-0.2 Hz) of SBP variability (50 min: 6.7 +/- 1.7 mmHg2 vs 3.4 +/- 0.5 mmHg2, P < 0.05), whereas the high dose of L-NAME not only increased the LF component (40 min: 11.7 +/- 2 mmHg2 vs 2.7 +/- 0.5 mmHg2, P < 0.001) but also decreased the mind frequency (MF: 0.2-0.6 Hz) component (60 min: 1.14 +/- 0.3 mmHg2 vs 1.7 +/- 0.1 mmHg2, P < 0.05) of SBP. 5. Losartan did not modify BP levels but had a tachycardic effect (+45 beats min-1). Moreover, losartan increased MF oscillations of SBP (4.26 +/- 0.49 mmHg2 vs 2.43 +/- 0.25 mmHg2, P < 0.001), prevented the BP rise provoked by the low-dose of L-NAME and delayed the BP rise provoked by the high-dose of L-NAME. Losartan also prevented the amplification of the LF oscillations of SBP induced by L-NAME; the decrease of the MF oscillations of SBP induced by L-NAME was reinforced after losartan. 6. We conclude that the renin-angiotensin system is involved in the increase in variability of SBP in the LF range which resulted from the withdrawal of the vasodilating influence of NO. We propose that NO may counterbalance LF oscillations provoked by the activity of the renin-angiotensin system.  相似文献   
269.
This paper generalizes the well‐known Diffusion Curves Images (DCI), which are composed of a set of Bezier curves with colors specified on either side. These colors are diffused as Laplace functions over the image domain, which results in smooth color gradients interrupted by the Bezier curves. Our new formulation allows for more color control away from the boundary, providing a similar expressive power as recent Bilaplace image models without introducing associated issues and computational costs. The new model is based on a special Laplace function blending and a new edge blur formulation. We demonstrate that given some user‐defined boundary curves over an input raster image, fitting colors and edge blur from the image to the new model and subsequent editing and animation is equally convenient as with DCIs. Numerous examples and comparisons to DCIs are presented.  相似文献   
270.
Rheological Properties of Metal Soaps in Concentrate Aqueous Dispersions The rheological behavior and the particle size distributions of calcium stearate dispersions were examined. From these investigations it is possible to propose a suitable quality profile for metal soap dispersions. For the handling of the dispersions it is advantageous if these products have a newtonic up to a slight pseudoplastic flow behavior with an average of particle size clear under 10 microns. A quality control should comprise the analysis of alcalinity, water content, rheological behavior and particle size distribution.  相似文献   
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