A gravity independent vapor absorption refrigerator

Design evaluation of vapor absorbing refrigerator systems operating independently of gravit

Finite element modeling of compression behavior of extruded polystyrene foam using X-ray tomography

Extruded polystyrene rigid foams have attracted a great attention as a superior load-bearing thermal insulation material since their implementation in building construction. One of the most common application areas of this type of thermal insulation material is under raft foundations, where the foam normally undergoes high levels of compression loads. The purpose of this research is to determine how to simulate and optimize the structural response of extruded polystyrene under compression stresses. The optimization has been achieved through investigating the relation between the foam microstructure and the global mechanical properties. The foam was first examined using X-ray tomography imaging technique to acquire some morphological information about the microstructure. The obtained morphological data of extruded polystyrene boards were then utilized to develop microstructure-based finite element models based on the so-called idealized realistic Kelvin cell. The finite element simulation was accomplished with the help of the nanoindentation technology to explore the mechanical properties of the cell wall material. The finite element models were validated by comparisons between the simulated and the experimental results. It has been found that the mechanical properties of the foam in different loading directions can be adequately simulated using the approach of the idealized realistic Kelvin cell. With the help of these models, a parameter study was carried out. This study included the effect of cell size and cell anisotropy on the mechanical response of extruded polystyrene boards under compression stresses. Charts relating between the foam microstructure characteristics and the compression behavior were generated based on the parametric study. © The Author(s) 2013. Reprints and permissions: sagepub.co.uk/journalsPermissions. nav

MANAGEMENT’S PERCEPTION OF STOCK DIVIDEND DISTRIBUTION IN AN EMERGING CAPITAL MARKET: THE CASE OF KUWAIT

The purpose of this study is to investigate perceptions of top managers of Kuwaiti companies regarding factors the affect their companies’ decision to distribute stock dividend ( SD ). A questionnaire listing 32 reasons that could explain companies’ decisions to declare SDs was distributed to a sample of 120 randomly selected top managers from 100 Kuwaiti companies and 73 responses were received (representing a 61% response rate ). Participants were classified according to: ( 1 )business sector ( investment, real estate, banking, service, and industrial ) and ( 2 ) size of SDs ( small ( less than 25% ) and large ( 25% or more )). Nonparametric statistical tests were employed to analyze the data.Stock Dividends, Importance Ratings, Trading Liquidity, Institutional Investors

Attentional bias toward negative and positive pictorial stimuli and its relationship with distorted cognitions, empathy, and moral reasoning among men with intellectual disabilities who have committed crimes

The aims of this study were to examine: (a) whether men with intellectual disabilities who have a history of criminal offending attend to affective pictorial stimuli in a biased manner, and (b) whether there is a relationship between an affective attentional bias and offence-supportive cognitions, empathy, and moral development. Forty-six men with intellectual disabilities who had a documented history of criminal offending, and 51 men who also had intellectual disabilities, but no such history, were recruited and asked to complete a computer-based dot-probe task using affective pictorial stimuli with randomisation, along with measures of distorted cognitions, empathy, and moral development. Those with a history of criminal offending endorsed significantly more offence-supportive cognitions, had significantly lower general empathy, and more “mature” moral development, as well as a significant attentional bias toward affective pictorial stimuli. Attentional bias significantly predicted offence-supportive cognitions, and vice versa, having controlled for offence history, and Full-Scale IQ, but this was not the case for empathy or moral development. While the findings require replication, interventions which aim to modify attention bias with this population should be tested

Spectrophotometric Determination of Omeprazole Sodium and Ranitidine Hydrochloride Using 2, 4-dinitrofluorobenzene and 4- chloro-7-nitrobenzen-2-oxa-1, 3-diazole Accompanied with a Kinetic Study

Two accurate, simple and sensitive spectrophotometric methods were developed for determination of omeprazole sodium and ranitidine hydrochloride in bulk and pharmaceutical dosage forms. The first method was based on the reaction of these drugs with 2, 4- dinitrofluorobenzene producing yellow colored products measured at λmax 470 nm and 420 nm for omeprazole sodium and ranitidine HCl, respectively. Beer’s law was obeyed in the concentration range from (5-40 µg.ml-1) for omeprazole sodium and (30-180 µg.ml-1) for ranitidine HCl with molar absorpitivity 9.202 x 103 Lmol-1cm-1 and 1.778 x 103 Lmol-1cm-1, respectively. The second method was based on the reaction of omeprazole sodium and ranitidine HCl with 4- Chloro-7-nitrobenzen-2-oxa-1, 3-diazole producing yellow colored adducts measured at λmax 481 nm and 468 nm for omeprazole sodium and ranitidine HCl, respectively. This method was accompanied with a kinetic study for ranitidine HCl. The absorbance-concentration plots were rectilinear over concentration range (2-12 µg.ml-1) and (0.025-0.15 µg.ml-1) for omeprazole sodium and ranitidine HCl with molar absorpitivity 4.062 x 104 Lmol-1cm-1 and 2.802 x 106 Lmol-1cm-1, respectively. These methods hold their accuracy and precision well when applied to the determination of omeprazole sodium and ranitidine HCl in their dosage forms

Progressive in vivo development of resistance to cefiderocol in Pseudomonas aeruginosa.

We report in vivo development of cefiderocol (FDC) resistance among four sequential Pseudomonas aeruginosa clinical isolates ST244 recovered from a single patient, without exposure to FDC, which raises concern about the effectiveness of this novel drug. The first recovered P. aeruginosa isolate (P-01) was susceptible to FDC (2 μg/mL), albeit this MIC value was higher than that of a wild-type P. aeruginosa (0.12-0.25 μg/ml). The subsequent isolated strains (P-02, P-03, P-04) displayed increasing levels of FDC MICs (8, 16, and 64 μg/ml, respectively). Those isolates also showed variable and gradual increasing levels of resistance to most β-lactams tested in this study. Surprisingly, no acquired β-lactamase was identified in any of those isolates. Whole-genome sequence analysis suggested that this resistance was driven by multifactorial mechanisms including mutational changes in iron transporter proteins associated with FDC uptake, ampC gene overproduction, and mexAB-oprM overexpression. These findings highlight that a susceptibility testing to FDC must be performed prior to any prescription

The effect of nitro-oleic versus losartan in diabetic nephropathy: modulation of parathyroid hormone-related protein

Background: Parathyroid hormone-related protein (PTHrP) involvement in the mechanisms related to angiotensin II (AngII)-induced renal injury has become an emerging concern. The current study was thus designed to compare the possible preventive and therapeutic effect of AngII antagonists, losartan and nitro-oleic (NO2-OA) acid, on diabetic nephropathy (DN) and evaluate their effect on PTHrP modulation as well as on the functional and histopathological parameters in the kidney of diabetic rats.  Materials and methods: Forty eight adult male Sprague Dawley rats were divided into control group, DN group, pre-diabetic nephropathy (pre-DN) losartan group, pre-diabetic nephropathy nitro-oleic acid (pre-DN NO2-OA) group, post-diabetic nephropathy (post-DN) losartan and post-diabetic nephropathy nitro-oleic acid (post-DN NO2-OA) groups. At the end of the study, systolic blood pressure (SBP), serum fasting glucose, glomerular filtration rate (GFR), urea, urea albumin excretion (UAE), serum angiotensin, renal PTHrP gene expression and correlations between PTHrP and SBP, serum glucose, AngII and kidney functions were evaluated. Histo- logical examination, Masson’s trichrome, periodic acid-Schiff staining as well as morphometric analysis and histopathological scoring for tubular and glomerular parameters have been carried out.  Results: Prophylactic losartan and NO2-OA were associated with improvement in SBP, serum glucose, urea, GFR, UAE, with reduction in serum AngII and PTHrP overexpression observed in diabetic kidney. Treatment with losartan and NO2-OA showed the same effect except that post-DN NO2-OA showed no significant effect regarding kidney function. Strong correlations were observed between PTHrP and SBP, serum glucose, AngII and kidney functions. Histopathological results revealed obvious improvement in glomerulosclerosis, vascular and tubular injury parameters in prophylactic groups especially with losartan.  Conclusions: Both pre and post-DN losartan, NO2-OA may have a potential role in protection and regression of DN through reduction of PTHrP overexpression.

Sptrx-2, a fusion protein composed of one thioredoxin and three tandemly repeated NDP-kinase domains is expressed in human testis germ cells

42 páginas, 9 figuras.Background Thioredoxins (Trx) are small redox proteins that function as general protein disulphide reductases and regulate several cellular processes such as transcription factor DNA binding activity, apoptosis and DNA synthesis. In mammalian organisms, thioredoxins are generally ubiquitously expressed in all tissues, with the exception of Sptrx-1 which is specifically expressed in sperm cells. Results We report here the identification and characterization of a novel member of the thioredoxin family, the second with a tissue-specific distribution in human sperm, termed Sptrx-2. The Sptrx-2 ORF (open reading frame) encodes for a protein of 588 amino acids with two different domains: an N-terminal thioredoxin domain encompassing the first 105 residues and a C-terminal domain composed of three repeats of a NDP kinase domain. The Sptrx-2 gene spans about 51 kb organized in 17 exons and maps at locus 7p13-14. Sptrx-2 mRNA is exclusively expressed in human testis, mainly in primary spermatocytes, while Sptrx-2 protein expression is detected from the pachytene spermatocytes stage onwards, peaking at round spermatids stage. Recombinant full-length Sptrx-2 expressed in bacteria displayed neither thioredoxin nor NDP kinase enzymatic activity. Conclusions The sperm specific expression of Sptrx-2, together with its chromosomal assignment to a position reported as a potential locus for flagellar anomalies and male infertility phenotypes such as primary ciliary dyskinesia, suggests that it might be a novel component of the human sperm axonemal organization.This work was supported by grants from the Swedish Medical Research Council (Projects 03P-14096-01A, 03X-14041-01A and 13X-10370), the Åke Wibergs Stiftelse, the Karolinska Institutet, the Södertörns Högskola and the Medical Research Fund of Tampere University Hospital.Peer reviewe