An antimicrobial activity of cytolytic T cells mediated by granulysin

Cytolytic T lymphocytes (CTLs) kill intracellular pathogens by a granule-dependent mechanism. Granulysin, a protein found in granules of CTLs, reduced the viability of a broad spectrum of pathogenic bacteria, fungi, and parasites in vitro. Granulysin directly killed extracellular Mycobacterium tuberculosis, altering the membrane integrity of the bacillus, and, in combination with perforin, decreased the viability of intracellular M. tuberculosis. The ability of CTLs to kill intracellular M. tuberculosis was dependent on the presence of granulysin in cytotoxic granules, defining a mechanism by which T cells directly contribute to immunity against intracellular pathogens.     

Security protocol for IEEE 802.11 wireless local area network

As Wireless Local Area Networks (WLANs) are rapidly deployed to expand the field of wireless products, the provision of authentication and privacy of the information transfer will be mandatory. These functions need to take into account the inherent limitations of the WLAN medium such as limited bandwidth, noisy wireless channel and limited computational power. Moreover, some of the IEEE 802.11 WLAN characteristics such as the use of a point coordinator and the polling based Point Coordination Function (PCF) have also to be considered in this design. In this paper, we introduce a security protocol for the IEEE 802.11 PCF that provides privacy and authentication, and is designed to reduce security overheads while taking into account the WLAN characteristics. We prove this protocol using the original and modified BAN logic.     

Patient adherence to cancer control regimens: Scale development and initial validation.

Describes the development of a 38-item self-report Adherence Determinants Questionnaire (ADQ) to assess 7 elements of patients' adherence to medical treatment and prevention: (1) perceptions of interpersonal care, (2) beliefs about susceptibility to disease, (3) beliefs about severity of disease, (4) assessments of perceived utility of adhering (efficacy and benefits vs costs of adhering), (5) perceptions of subjective social norms for adhering, (6) intentions to adhere, and (7) perceptions of supports available for and absence of barriers to adherence. Past adherence and health value were also assessed. In 4 diverse field settings, intentions to adhere were most highly correlated with the perceived utility of adhering. Adherence (self-reported and objectively measured) was related most strongly to the presence of supports for and the absence of barriers to adherence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Practical implant dentistry--the mandibular removable overdenture prosthesis

The fully edentulous mandible presents functional, esthetic, and psychological challenges for the patient and the dentist. The mandibular overdenture supported by endosseous implants can provide a superior treatment modality, overcoming many of the difficulties inherent in the conventional denture. Advantages cited are increased denture retention, improved chewing efficiency, maintenance of bone height, replacement of lost anatomy, increased denture stability, reduction of soft tissue coverage and extension of the prosthesis, and easy access for hygiene maintenance. The major disadvantage rests with the patient's intolerance of a removable prosthetic design.     

Performance and design evaluation of WDM stars

A performance tool for evaluating the design of a wavelength-division-multiplexing (WDM) passive star is provided. The design parameters that determine the system performance are the number of wavelengths in the system, the number of receivers per node, the wavelength allocation per receiver, the transmitter tunability range, and the node buffer size. An exact analysis becomes prohibitively complex for even moderately sized systems. Therefore, an efficient approximate analysis with drastically reduced computational complexity is presented, incorporating all of the above design parameters, in addition to the channel access protocol and the nonhomogeneous traffic patterns of high-bandwidth networks. The approach produces very accurate results and can help in selecting the most cost-effective system design for given performance requirements     

Use of FEA for Design of Posttensioning Anchor Head

This paper deals with the development process of a multistrand wedge anchor head mechanism. Generally, this development process involves a number of different experimental tests but, while informative and necessary, these tests cannot provide valuable information such as internal strain distributions, stress concentrations, or percentage of the anchorage yielded volume. To answer these questions, an efficient numerical finite element model has been developed and validated which includes nonlinearities such as: large strain; plasticity; and contact between interfaces. First, this paper presents a comparison between numerical and experimental results of VSL International CS 6-31 anchorage mechanism under standard loading conditions. Based on the good agreement between results, the numerical model was then used to assess the anchorage behavior under more severe loading conditions and improved mechanical characteristics. Through anchorage deflection, von Mises stresses as well as equivalent plastic strains, it is shown that the anchor areas most severely stressed are concentrated along its peripheral wedge cavities and that, while suitable for typical loadings, the VSL anchorage is not acceptable for the more severe loading conditions examined. Finally, this paper underlines the proposed numerical model usefulness with regard to the development of new post-tensioned anchorages by providing information not otherwise available.     

Associations of endothelial dysfunction and arterial stiffness with intradialytic hypotension and hypertension

Intradialytic hypotension and hypertension are both independently associated with mortality among persons with end-stage renal disease on hemodialysis. Endothelial dysfunction and arterial stiffness are two possible mechanisms underlying these phenomena, but their association with hemodynamic instability during dialysis has not been evaluated. Thirty patients were recruited from chronic dialysis units at San Francisco General Hospital and San Francisco Veterans Affairs Medical Center. Endothelial dysfunction was assessed with flow-mediated dilation of the brachial artery after upper arm occlusion. Arterial stiffness was assessed using carotid-femoral pulse wave velocity measured by tonometry. Intradialytic hypotension and hypertension were defined as the average decrease in systolic blood pressure (SBP) over 1 week, as well as the frequency over 1 month of hypotension or hypertension. Every 5% decrease in flow-mediated dilation was associated with a 7.5 mmHg decrease in SBP after adjustment for phosphorus, body mass index, atherosclerosis, and ultrafiltration (P=0.02). Every 5 m/s increase in pulse wave velocity was associated with an 8 mmHg increase in SBP after adjustment for predialysis SBP and ultrafiltration (P=0.03). Over 1 month, every 5% lower flow-mediated dilation was associated with a 10% higher frequency of hypotension (P=0.09), and every 5 m/s increase in pulse wave velocity was associated with an 15% higher frequency of hypertension (P=0.02). In a cross-sectional analysis of 30 dialysis patients, endothelial dysfunction and arterial stiffness were independently associated with intradialytic hypotension and intradialytic hypertension, respectively. Elucidating these potential mechanisms of hemodynamic instability during dialysis may facilitate development of treatment strategies specific to this pathophysiology.     

A data-derived reference signal technique for adaptive arrays

A new technique is presented for reference signal generation in adaptive arrays, and it is shown how it can be used in a binary FSK communication system. This method consists of encoding the message bit stream at the transmitter to convert it to a first-order Markov source with a transition probability of p>1/2. Then, in the receiver, each detected bit is used to predict the next bit, and the predicted bits are used to generate a reference signal. The performance of an FSK system based on this concept is analyzed, and an experimental system is described. This experimental system demonstrated that the reference signal generation concept is feasible and showed that this technique could be used to protect an FSK communication system from a CW interference signal