LEE: Light‐Weight Energy‐Efficient encryption algorithm for sensor networks

Data confidentiality in wireless sensor networks is mainly achieved by RC5 and Skipjack encryption algorithms. However, both algorithms have their weaknesses, for example RC5 supports variable-bit rotations, which are computationally expensive operations and Skipjack uses a key length of 80-bits, which is subject to brute force attack. In this paper we introduce a light-weight energy- fficient encryption-algorithm (LEE) for tiny embedded devices, such as sensor network nodes. We present experimental results of LEE under real sensor nodes operating in TinyOS. We also discuss the secrecy of our algorithm by presenting a security analysis of various tests and cryptanalytic attacks

Molecular identification of CTX-M, TEM and SHV β-lactamases in �Klebsiella pneumoniae isolated from respiratory system of patients in the ICU of educational hospitals in Tehran

Background: Extended-spectrum beta-lactamases (ESBL) producing isolates of Klebsiella pneumoniae which have been increased in the hospitals were resulting in limitation of therapeutic options. The aims of this study were to evaluate the antibiotic susceptibility pattern and presence of ESBL genes in clinical isolates of Klebsiella pneumoniae from patients admitted to the intensive care units (ICUs). Materials and Methods: In this descriptive cross-sectional study, a total of 65 Klebsiella pneumoniae strains were isolated from ICUs of educational hospitals in Tehran. Identification was performed using biochemical tests and the antimicrobial susceptibility was performed as recommended by the Clinical and Laboratory Standards Institute (CLSI). Molecular analysis of the ESBL genes was performed by Multiplex PCR (M-PCR). Results: Most of the isolates were resistant to Cotrimoxazole (72.3), Gentamicin (67.7) and Ampicillin (69.2) and the highest susceptibility was seen for Ciprofloxacin (50.8) Tetracycline (49.2), Imipenem (46.3) and Ceftriaxone (43.1). Among the ESBL-producing genes, blaCTX-M (55.3 ) was the most prevalent, followed by blaTEM (41.5 ) and blaSHV (10.7 ). The results showed that 1.5 of the isolates had concurrently blaTEM/ blaSHV and blaSHV/ blaCTX-M genes and 21.6 of isolates the blaTEM/ blaCTX-M genes. Conclusion: These findings reveal the high prevalence of multi drug resistant and ESBL-producing Klebsiella pneumoniae in patients hospitalized in ICUs and emphasize the need for appropriate infection control policies

Nanoliposomal Nitroglycerin Exerts Potent Anti-Inflammatory Effects.

Nitroglycerin (NTG) markedly enhances nitric oxide (NO) bioavailability. However, its ability to mimic the anti-inflammatory properties of NO remains unknown. Here, we examined whether NTG can suppress endothelial cell (EC) activation during inflammation and developed NTG nanoformulation to simultaneously amplify its anti-inflammatory effects and ameliorate adverse effects associated with high-dose NTG administration. Our findings reveal that NTG significantly inhibits human U937 cell adhesion to NO-deficient human microvascular ECs in vitro through an increase in endothelial NO and decrease in endothelial ICAM-1 clustering, as determined by NO analyzer, microfluorimetry, and immunofluorescence staining. Nanoliposomal NTG (NTG-NL) was formulated by encapsulating NTG within unilamellar lipid vesicles (DPhPC, POPC, Cholesterol, DHPE-Texas Red at molar ratio of 6:2:2:0.2) that were ~155 nm in diameter and readily uptaken by ECs, as determined by dynamic light scattering and quantitative fluorescence microscopy, respectively. More importantly, NTG-NL produced a 70-fold increase in NTG therapeutic efficacy when compared with free NTG while preventing excessive mitochondrial superoxide production associated with high NTG doses. Thus, these findings, which are the first to reveal the superior therapeutic effects of an NTG nanoformulation, provide the rationale for their detailed investigation for potentially superior vascular normalization therapies

Numerical study of size-dependent instability of nems considering molecular force and elastic support conditions

Nano-electromechanical systems (NEMS) sensors are recently used as powerful medical detectors for detection of disease. In this research paper, the modified couple stress non-classic continuum theory is applied to examine the size effect on the pull-in instability of beam-type NEMS sensor at submicron separations considering the van der Waals attraction. The proposed model takes the non-classic support conditions into account using rotational springs at supported end of the simply supported nano-beam. In order to solve the nonlinear constitutive equation of the nano-beams, finite difference numerical solution employed. The results reveal significant influence of the size dependency, elastic support conditions and van der Waals attraction on the pull-in characteristics of beam-type NEMS. © 2006-2014 Asian Research Publishing Network (ARPN)

The Influence of Geometrical Shape Changes on Wave Overtopping: a Laboratory and SPH Numerical Study

This paper presents laboratory investigations of four “retrofit” suggestions for attenuating the overtopping from vertical seawall. Two-dimensional physical model experiments were performed on a vertical seawall with a 1:20 sloping foreshore. Additionally, a Lagrangian, particle based SPH methodology was employed to simulate the wave hydrodynamics and overtopping for the recurve configuration. The experimental and numerical results confirm satisfactory performance. For the tested configurations in the laboratory, the mean overtopping discharges decreased over 60% and maximum individual discharge decreased 40% on recurve wall under both impulsive and non-impulsive conditions. A significant reduction was also observed in mitigating overtopping discharge by using model vegetation and reef breakwater, while diffraction pillar was not found satisfactory

The norovirus NS3 protein is a dynamic lipid- and microtubule-associated protein involved in viral RNA replication

Norovirus (NoV) infections are a significant health burden to society, yet the lack of reliable tissue culture systems has hampered the development of appropriate antiviral therapies. Here we show that the NoV NS3 protein, derived from murine NoV (MNV), is intimately associated with the MNV replication complex and the viral replication intermediate double-stranded RNA (dsRNA). We observed that when expressed individually, MNV NS3 and NS3 encoded by human Norwalk virus (NV) induced the formation of distinct vesicle-like structures that did not colocalize with any particular protein markers to cellular organelles but localized to cellular membranes, in particular those with a high cholesterol content. Both proteins also showed some degree of colocalization with the cytoskeleton marker β-tubulin. Although the distribution of MNV and NV NS3s were similar, NV NS3 displayed a higher level of colocalization with the Golgi apparatus and the endoplasmic reticulum (ER). However, we observed that although both proteins colocalized in membranes counterstained with filipin, an indicator of cholesterol content, MNV NS3 displayed a greater association with flotillin and stomatin, proteins known to associate with sphingolipid- and cholesterol-rich microdomains. Utilizing time-lapse epifluorescence microscopy, we observed that the membrane-derived vesicular structures induced by MNV NS3 were highly motile and dynamic in nature, and their movement was dependent on intact microtubules. These results begin to interrogate the functions of NoV proteins during virus replication and highlight the conserved properties of the NoV NS3 proteins among the seven Norovirus genogroups

Quantitative Model of the Behavior of the Limiting Current Oxygen Sensors

AbstractA physicochemical model of the I(V) response of amperometric oxygen sensors based in ion conduction is proposed. Although the qualitative behavior of these devices is well known, there is a lack of a quantitative description of the response of the sensors in their normal operation conditions. The model focuses on diffusion across a porous layer and minimization of the oxygen-ion electrochemical potential in steady state. It provides an analytical expression describing the current-voltage dependence in terms of oxygen diffusivity, ionic conductivity, temperature and geometrical parameters. Experimental measurements of our owndesigned amperometric ceramic sensors are in agreement with the proposed model

Application of smoothed particle hydrodynamics in evaluating the performance of coastal retrofit structures

This study develops an accurate numerical tool for investigating optimal retrofit configurations in order to minimize wave overtopping from a vertical seawall due to extreme climatic events and under changing climate. A weakly compressible smoothed particle hydrodynamics (WCSPH) model is developed to simulate the wave-structure interactions for coastal retrofit structures in front of a vertical seawall. A range of possible physical configurations of coastal retrofits including re-curve wall and submerged breakwater are modelled with the numerical model to understand their performance under different wave and structural conditions. The numerical model is successfully validated against laboratory data collected in 2D wave flume at Warwick Water Laboratory. The findings of numerical modelling are in good agreement with the laboratory data. The results indicate that recurve wall is more effective in mitigating wave overtopping and provides more resilience to coastal flooding in comparison to base-case (plain vertical wall) and submerged breakwater retrofit

Evaluation of response to preoperative chemotherapy versus surgery alone in gastroesophageal cancer: Tumor resectability, pathologic results and post-operative complications

Gastroesophageal cancer is one of the most common types of cancer worldwide. Despite significant developments in management, 5-year survival in the developing world is less than 20 percent. Due to restricted research about the impact of preoperative chemotherapy (POC) on tumor resection, pathological response and postoperative complications in Iran, we designed and implemented the present retrospective cross- sectional study on 156 patients with gastroesophageal cancer (GEc) between 2013 and 2015 at Shariati Hospital of Tehran. Two groups were included, the first group had previously received preoperative chemotherapy and the second group had only undergone surgery. All patients were followed for at least one year after the operation in terms of tumor recurrence, relapse free survival and one-year survival. The two groups were eventually compared regarding tumor resection, pathological response, postoperative complications, recurrence rate and survival. The mean age was 66.5± 7.3 years and 78 percent were male. The tumor resectability, pathological response and postoperative complications in the group which received POC were 93.5, 21.8 and 12.8, respectively, and in the surgery alone group figures for tumor resection and postoperative complications were 76 and 29.5, respectively. Also based on our study the 5-year survival in the POC group was better (79.5 vs. 66.5). Using standard neoadjuvant regimens (preoperative chemotherapy/ chemoradiotherapy) beforesurgery could increase tumor resectability, pathological response, and improve the general status of the patients. Therefore using POC may be recommended over surgery alone. © 2016, Asian Pacific Journal of Cancer Prevention