Incorporation of a Hydrophobic Antibacterial Peptide into Amphiphilic Polyelectrolyte Multilayers: A Bioinspired Approach to Prepare Biocidal Thin Coatings

A non‐water‐soluble natural antibacterial peptide, gramicidin A, has been successfully incorporated into polyelectrolyte assemblies to elaborate biocidal thin films. For this, we used a double strategy, the first step of which consists of complexing the peptide by a non‐denaturing anionic amphiphilic polysaccharide, namely a hydrophobically modified carboxymethylpullulan. We demonstrate that the use of this amphiphilic anionic derivative allows to efficiently solubilize the peptide in aqueous solution, without denaturation. The amount of peptide solubilized by the amphiphilic polysaccharide was optimized by systematically varying the hydrophobicity and the molar mass of the CMP derivative. In a second step, the negatively charged complex was layer‐by‐layer assembled with cationic poly(L‐lysine) to form biofunctionalized thin films. The amount of peptide incorporated in the multilayers was controlled by changing the number of deposited complex layers, and was quantified by UV spectroscopy. The antibacterial activity of the resulting biofunctionalized films was evidenced against a gram‐positive bacterium, E. faecalis. We demonstrated that the biocidal activity resulted from a double mechanism: contact between bacteria and the film surface, and release of the peptide into the solution surrounding the film. We also showed that the peptide was not completely removed from the film after rinsing, which insured preservation of the biocidal activity of the film surface.     

A wavelet approach to detecting electrocautery noise in the ECG.

A software approach has been developed for detecting electrocautery noise in the electrocardiogram (ECG) using a wavelet decomposition of the signal. With this approach, a clinical monitoring expert system can be forewarned of potential artifacts in trend values derived from the ECG, allowing it to proceed with caution when making decisions based on these trends. In 15 operations spanning 38.5 h of ECG data, we achieved a false positive rate of 0.71% and a false negative rate of 0.33%. While existing hardware approaches detect the source of the noise without any ability to assess its impact on the measured ECG, our software approach detects the presence of noise in the signal itself. Furthermore, the software approach is cheaper and easier to implement in a clinical environment than existing hardware approaches.     

英国零售业规划政策

1引言 本文将“零售业规划”（retail planning）定义为在一个给定时期内应发展的零售业数量、种类和地点的决策过程。这个过程将通过与私营业主（零售业主和地产开发商）及公共部门（地方和国家政府）的互动来进行实施。私营业主与公共部门的出发点是不同的,私营业主通常会要求维持或增加销售额和利润．而公共部门则以非商业目标为根本．追求制定符合更广泛的公众利益的政策。     

混沌的家庭无线网

随着越来越多的家庭安装Wi-Fi,信道拥塞问题日益严重。     

A comparison of five heuristics for the multiple depot vehicle scheduling problem

Given a set of timetabled tasks, the multi-depot vehicle scheduling problem consists of determining least-cost schedules for vehicles assigned to several depots such that each task is accomplished exactly once by a vehicle. In this paper, we propose to compare the performance of five different heuristics for this well-known problem, namely, a truncated branch-and-cut method, a Lagrangian heuristic, a truncated column generation method, a large neighborhood search heuristic using truncated column generation for neighborhood evaluation, and a tabu search heuristic. The first three methods are adaptations of existing methods, while the last two are new in the context of this problem. Computational results on randomly generated instances show that the column generation heuristic performs the best when enough computational time is available and stability is required, while the large neighborhood search method is the best alternative when looking for good quality solutions in relatively fast computational times.     

Vicarious traumatization, spirituality, and the treatment of sexual abuse survivors: A national survey of women psychotherapists.

Should psychotherapists limit their clinical work with trauma survivors to avoid being traumatized themselves? Vicarious traumatization (VT—the symptoms similar to posttraumatic stress disorder and the disruption in cognitive schemas reported in clinicians who are exposed to the trauma material of their clients—was assessed in a national survey of 1,000 women psychotherapists. Therapists with higher levels of exposure to sexual abuse material reported significantly more trauma symptoms but no significant disruption of cognitive schemas. Spiritual well-being, a key area thought to be damaged by VT, was found to be higher for those clinicians who saw more sexual abuse survivors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reconstruction of chronic and complete dislocations of the acromioclavicular joint

The authors report on a technique for the treatment of symptomatic, chronic complete dislocations of the acromioclavicular joint. The coracoacromial ligament is substituted for the coracoclavicular ligaments, and a special temporary coracoclavicular lag screw is used to stabilize the clavicle to the coracoid during ligament healing. The technique has been used on 23 patients who were observed for an average of 5.2 years. Good to excellent results were obtained in 19 of 23 patients. The four patients with fair or poor results had one or more resections of the distal clavicle before the reconstruction. Subjectively, 22 of 23 patients reported improvement in their shoulder.     

High-inversion densities in Nd:YAG-upconversion and bleaching

We report on the investigation of upconversion in Nd:YAG and its implications for intensely pumped devices. Analysis of lifetime measurements and the performance of a 1 at.% Nd-doped YAG amplifier give an Auger upconversion rate of 7×10³ s^-1. This is significantly smaller than previously reported, but modeling of the performance of Nd:YAG devices with high-inversion densities shows that even this rate can still seriously degrade the small-signal gain and significantly increase the thermal load. The variation of cross-relaxation and upconversion rates with doping level is also described. Finally, it is found that the effect of bleaching of the Nd:YAG absorption can lead to a reduced spatial overlap between the signal and inversion profiles and thus can also significantly reduce the gain     

Water as reactive gas to prepare titanium oxynitride thin films by reactive sputtering

Thin films of titanium oxynitride were successfully prepared by dc reactive magnetron sputtering using a titanium metallic target, argon, nitrogen and water vapour as reactive gases. The nitrogen partial pressure was kept constant during every deposition whereas that of the water vapour was systematically changed from 0 to 0.1 Pa. The evolution of the deposition rate with an increasing amount of water vapour injected into the process was correlated with the target poisoning phenomenon estimated from the target potential. Structure and morphology of the films were analysed by X-ray diffraction and scanning electron microscopy. Films were poorly crystallised or amorphous with a typical columnar microstructure. Nitrogen, oxygen and titanium concentrations were determined by Rutherford backscattering spectroscopy and nuclear reaction analysis, and the amount of hydrogen in the films was also quantified. Optical transmittance in the visible region and electrical conductivity measured against temperature were gradually modified from metallic to semiconducting behaviour with an increasing supply of the water vapour partial pressure. Moreover, an interesting maximum of the electrical conductivity was observed in this transition, for a small amount of water vapour.