bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Aluminosilicate Mineral Nano-Clay Fillers on Polysulfone Mixed Matrix Membrane for Carbon Dioxide Removal
Authors: P.C. Oh , N. A. Mansur 
Published: August 2014

Over the last few decades, significant improvements in the performance of polymeric membranes for gas separation have been made. Nevertheless, the existing membrane materials need to be enhanced in order to fully exploit their gas separation application opportunities on industrial scale. Mixed matrix membrane which combines the advantages of the highly selective fillers and desirable properties of the polymer matrix is explored to overcome the trade-off trend between gas permeability and selectivity. This paper describes the effect of aluminosilicate mineral nano-clay fillers on polysulfone (PSF) mixed matrix membrane. In this study, different types of montmorillonite (MMT) nano-clays were used as fillers to fabricate asymmetric flat sheet mixed matrix membrane (MMM) via dry-wet phase inversion method. The interaction between the type of organoclay and its loading is also studied. The synthesis of MMM required N-methyl-2-pyrrolidone (NMP) as solvent and deionized water as coagulant. The fabricated MMMs were characterized by thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC) and field emission scanning electron microsropy (FESEM). Thin asymmetric membrane with dense skin layer and porous sub-structure was successfully fabricated. Results showed enhancement in MMM stability relative to neat PSF membrane. It is also found that higher nano-clay loading resulted in significant agglomeration, nevertheless, there appears to be improved adhesion between the polymer and nano-clay.
Synthesis and Preparation of Asymmetric PSf/ZIF-8 Mixed Matrix Membrane for CO2/CH4 Separation
Authors: Md Nordin Nik Abdul Hadi , Ismail Ahmad Fauzi , Mustafa Azeman 
Published: August 2014

Utilizing nano-size filler into polymer matrix would overcome challenges in developing MMM by providing good dispersion in polymer matrix, high contact polymer-filler even at low filler loading. Asymmetric neat Polysulfone (PSf) and PSf/Zeolitic Imidazole Framework-8 (PSf/ZIF-8) mixed matrix membrane was prepared using dry/wet inversion method. Membrane prepared was coated with 3wt% of polydimethylsiloxane (PDMS) in n-hexane and undergoes heat treatment. The membranes was characterized using x-ray diffraction (XRD), thermagravimetric analysis (TGA), differential scanning calorimetry (DSC), and gas permeation test at 4 bar. XRD pattern revealed that ZIF-8 was successfully synthesis with crystal size around 73nm. Lowered membrane Tg after embodiment of ZIF-8 suggests that additional free volume form, while thermal stability up to 350°C related to ZIF-8 stability. Neat PSf prepared shows CO2 permeance at 4.97 GPU with CO2/CH4 selectivity at 7.52. Interestingly, incorporation of ZIF-8 showing improvement for both CO2 permeance and CO2/CH4 selectivity up to 51% and 47% respectively. Thus, employing nano ZIF-8 as filler into PSf matrix has resultant promising membrane for CO2/CH4 separation.
Refined abelian Stark conjectures and the equivariant leading term conjecture of Burns
Authors: Sano T. 
Published: August 2014

AbstractWe formulate a conjecture which generalizes Darmon’s ‘refined class number formula’. We discuss relations between our conjecture and the equivariant leading term conjecture of Burns. As an application, we give another proof of the ‘except$2$-part’ of Darmon’s conjecture, which was first proved by Mazur and Rubin.
Trihyperkähler reduction and instanton bundles on
Authors: Jardim Marcos , Verbitsky Misha 
Published: August 2014

AbstractA trisymplectic structure on a complex $2n$-manifold is a three-dimensional space ${\rm\Omega}$ of closed holomorphic forms such that any element of ${\rm\Omega}$ has constant rank $2n$, $n$ or zero, and degenerate forms in ${\rm\Omega}$ belong to a non-degenerate quadric hypersurface. We show that a trisymplectic manifold is equipped with a holomorphic 3-web and the Chern connection of this 3-web is holomorphic, torsion-free, and preserves the three symplectic forms. We construct a trisymplectic structure on the moduli of regular rational curves in the twistor space of a hyperkähler manifold, and define a trisymplectic reduction of a trisymplectic manifold, which is a complexified form of a hyperkähler reduction. We prove that the trisymplectic reduction in the space of regular rational curves on the twistor space of a hyperkähler manifold $M$ is compatible with the hyperkähler reduction on $M$. As an application of these geometric ideas, we consider the ADHM construction of instantons and show that the moduli space of rank $r$, charge $c$ framed instanton bundles on $\mathbb{C}\mathbb{P}^{3}$ is a smooth trisymplectic manifold of complex dimension $4rc$. In particular, it follows that the moduli space of rank two, charge $c$ instanton bundles on $\mathbb{C}\mathbb{P}^{3}$ is a smooth complex manifold dimension $8c-3$, thus settling part of a 30-year-old conjecture.
Abundant and Diverse Clustered Regularly Interspaced Short Palindromic Repeat Spacers in Clostridium difficile Strains and Prophages Target Multiple Phage Types within This Pathogen
Authors: Hargreaves Katherine R. , Flores Cesar O. , Lawley Trevor D. , Clokie Martha R. J. 
Published: August 2014

ABSTRACT

Clostridium difficile
is an important human-pathogenic bacterium causing antibiotic-associated nosocomial infections worldwide. Mobile genetic elements and bacteriophages have helped shape
C. difficile
genome evolution. In many bacteria, phage infection may be controlled by a form of bacterial immunity called the clustered regularly interspaced short palindromic repeats/CRISPR-associated (CRISPR/Cas) system. This uses acquired short nucleotide sequences (spacers) to target homologous sequences (protospacers) in phage genomes.
C. difficile
carries multiple CRISPR arrays, and in this paper we examine the relationships between the host- and phage-carried elements of the system. We detected multiple matches between spacers and regions in 31
C. difficile
phage and prophage genomes. A subset of the spacers was located in prophage-carried CRISPR arrays. The CRISPR spacer profiles generated suggest that related phages would have similar host ranges. Furthermore, we show that
C. difficile
strains of the same ribotype could either have similar or divergent CRISPR contents. Both synonymous and nonsynonymous mutations in the protospacer sequences were identified, as well as differences in the protospacer adjacent motif (PAM), which could explain how phages escape this system. This paper illustrates how the distribution and diversity of CRISPR spacers in
C. difficile
, and its prophages, could modulate phage predation for this pathogen and impact upon its evolution and pathogenicity.

IMPORTANCE
Clostridium difficile
is a significant bacterial human pathogen which undergoes continual genome evolution, resulting in the emergence of new virulent strains. Phages are major facilitators of genome evolution in other bacterial species, and we use sequence analysis-based approaches in order to examine whether the CRISPR/Cas system could control these interactions across divergent
C. difficile
strains. The presence of spacer sequences in prophages that are homologous to phage genomes raises an extra level of complexity in this predator-prey microbial system. Our results demonstrate that the impact of phage infection in this system is widespread and that the CRISPR/Cas system is likely to be an important aspect of the evolutionary dynamics in
C. difficile
.
Structured approach in improving weekend handovers in a medical high dependency unit
Authors: Patel Roma , Thiagarajan Prarthana 
Published: August 2014

AbstractWeekend admissions to hospital have been associated with adverse patient outcomes, including higher morbidity and mortality risk in general medicine and surgery. The reasons behind this are likely to be multifactorial and include reduced senior clinician-led care, decreased overall workforce, and ineffective or incomplete handover. With the advent of shift-work patterns, robust handover between medical teams is of paramount importance, particularly before weekends. This has been reflected in recent publications by Royal College of Physicians (acute care toolkit 1: handover, May 2011), that identified handover as an error-prone process and issued guidelines designed to optimise its effectiveness.The aim of this project was to evaluate weekend patient mortality and success of handover on the medical high dependency unit of a large teaching hospital in the United Kingdom, before and after introduction of a structured handover tool on Friday afternoons during May 2013. This unit is registrar-led at weekends. Weekend mortality decreased from 43% in March 2013 to 22% in May 2013 (odds ratio 0.37, 95% CI 0.19-0.68, p=0.07). Documentation of resuscitation status and escalation plans increased from 75% in March 2013 to 93% in May 2013. There was universal positive feedback from registrars involved with the handover tool, who provided senior cover during the weekends in May 2013. It is hoped that structured, written handover will ultimately become commonplace in this unit and will improve patient safety at weekends.
p53 Promotes Cell Survival due to the Reversibility of Its Cell-Cycle Checkpoints
Authors: Lukin Dana J. , Carvajal Luis A. , Liu Wen-jun , Resnick-Silverman Lois , Manfredi James J. 
Published: August 2014

Abstract
The tumor suppressor p53 (TP53) has a well-studied role in triggering cell-cycle checkpoint in response to DNA damage. Previous studies have suggested that functional p53 enhances chemosensitivity. In contrast, data are presented to show that p53 can be required for cell survival following DNA damage due to activation of reversible cell-cycle checkpoints. The cellular outcome to DNA damage is determined by the duration and extent of the stimulus in a p53-dependent manner. In response to transient or low levels of DNA damage, p53 triggers a reversible G2 arrest, whereas a sustained p53-dependent cell-cycle arrest and senescence follows prolonged or high levels of DNA damage. Regardless of the length of treatment, p53-null cells arrest in G2, but ultimately adapt and proceed into mitosis. Interestingly, they fail to undergo cytokinesis, become multinucleated, and then die from apoptosis. Upon transient treatment with DNA-damaging agents, wild-type p53 cells reversibly arrest and repair the damage, whereas p53-null cells fail to do so and die. These data indicate that p53 can promote cell survival by inducing reversible cell-cycle arrest, thereby allowing for DNA repair. Thus, transient treatments may exploit differences between wild-type p53 and p53-null cells.
Implications: Although p53 status has been suggested as a clinical predictor of chemotherapeutic efficacy, studies to date have not always supported this. This study demonstrates that p53 is still an important determinant of cell fate in response to chemotherapy, under the appropriate treatment conditions. Mol Cancer Res; 13(1); 16–28. ©2014 AACR.
Autotaxin and LPA1 and LPA5 Receptors Exert Disparate Functions in Tumor Cells versus the Host Tissue Microenvironment in Melanoma Invasion and Metastasis
Authors: Lee Sue-Chin , Fujiwara Yuko , Liu Jianxiong , Yue Junming , Shimizu Yoshibumi , Norman Derek D. , Wang Yaohong , Tsukahara Ryoko , Szabo Erzsebet , Patil Renukadevi , Banerjee Souvik , Miller Duane D. , Balazs Louisa , Ghosh Manik C. , Waters Christopher M. , Oravecz Tamas , Tigyi Gabor J. 
Published: August 2014

Abstract
Autotaxin (ENPP2/ATX) and lysophosphatidic acid (LPA) receptors represent two key players in regulating cancer progression. The present study sought to understand the mechanistic role of LPA G protein–coupled receptors (GPCR), not only in the tumor cells but also in stromal cells of the tumor microenvironment. B16F10 melanoma cells predominantly express LPA5 and LPA2 receptors but lack LPA1. LPA dose dependently inhibited invasion of cells across a Matrigel layer. RNAi-mediated knockdown of LPA5 relieved the inhibitory effect of LPA on invasion without affecting basal invasion. This suggests that LPA5 exerts an anti-invasive action in melanoma cells in response to LPA. In addition, both siRNA-mediated knockdown and pharmacologic inhibition of LPA2 reduced the basal rate invasion. Unexpectedly, when probing the role of this GPCR in host tissues, it was found that the incidence of melanoma-derived lung metastasis was greatly reduced in LPA5 knockout (KO) mice compared with wild-type (WT) mice. LPA1-KO but not LPA2-KO mice also showed diminished melanoma-derived lung metastasis, suggesting that host LPA1 and LPA5 receptors play critical roles in the seeding of metastasis. The decrease in tumor cell residence in the lungs of LPA1-KO and LPA5-KO animals was apparent 24 hours after injection. However, KO of LPA1, LPA2, or LPA5 did not affect the subcutaneous growth of melanoma tumors.
Implications: These findings suggest that tumor and stromal LPA receptors, in particular LPA1 and LPA5, play different roles in invasion and the seeding of metastasis. Mol Cancer Res; 13(1); 174–85. ©2014 AACR.
Postoperative outcomes following preoperative inspiratory muscle training in patients undergoing cardiothoracic or upper abdominal surgery: a systematic review and meta analysis
Authors: Mans Christina M , Reeve Julie C , Elkins Mark R 
Published: August 2014

Objective: To evaluate whether preoperative inspiratory muscle training is effective in preventing postoperative pulmonary complications and reducing length of hospital stay in people undergoing cardiothoracic or upper abdominal surgery. Data sources: Medline, CINAHL, AMED, PsychINFO, Scopus, PEDro, and the Cochrane Library. Review methods: A systematic review and meta analysis of randomized controlled trials (or quasi-randomized controlled trials) investigating a form of preoperative inspiratory muscle training, compared with sham or no inspiratory muscle training. Participants were adults (16 years and over) awaiting elective open cardiac, thoracic, or upper abdominal surgery. Methodological quality was assessed using the PEDro scale. Results: Eight studies involving 295 participants were eligible for inclusion. The trained group had significantly higher maximal inspiratory pressure at the end of the preoperative training period (mean difference: 15 cm H2O, 95% confidence interval (CI): 9 to 21). This benefit was maintained through the early postoperative period, when lung function also recovered significantly more quickly in the trained group. Inspiratory muscle training also substantially reduced postoperative pulmonary complications (relative risk 0.48, 95% CI 0.26 to 0.89). Although not statistically significant, length of hospital stay also tended to favour the trained group. There were no statistically significant differences between the groups for the remaining outcomes. Participant satisfaction with inspiratory muscle training was high. Conclusion: Preoperative inspiratory muscle training significantly improves respiratory (muscle) function in the early postoperative period, halving the risk of pulmonary complications. The training does not increase length of stay, but more data are required to confirm whether it reduces length of stay.
Management of Acute Calcific Tendinitis Around the Hip Joint
Authors: Park Sang-Min , Baek Ji-Hoon , Ko Young-Bong , Lee Han-Jun , Park Ki Jeong , Ha Yong-Chan 
Published: August 2014

Background: Although the natural history of calcific tendinitis within the rotator cuff of the shoulder is established, the natural history of calcific tendinitis around the hip joint remains unknown. Purpose: To examine the duration of symptoms including pain, the location of calcific tendinitis around the hip joint, the radiologic course of calcium phosphate crystals, and the proportion of patients who required surgical treatment. Study Design: Case series; Level of evidence, 4. Methods: Thirty hips (29 patients) with acute calcific tendinitis were treated between January 2010 and December 2012. Level of subjective hip pain using the visual analog scale pain score, radiologic type, and the location and size of calcium deposits were measured during a follow-up period of 12 to 32 months. Results: The 29 patients included 7 men (24%) and 22 women (76%) with a mean age of 51.5 years (range, 28-78 years). All visual analog scale pain scores significantly improved from a mean of 7.1 to 0.8 at the latest follow-up ( P < .001). The most common site of calcium deposition was the tendon of the gluteus medius. During follow-up, calcium deposition completely resolved in 5 of 20 hips. Symptoms in 23 patients (24 hips) responded to nonoperative treatment. Two patients (2 hips) were treated with ultrasound-guided local anesthetic and steroid injection. Four patients (4 hips) with long duration (>3 months) of severe pain, solid type, and large size (range, 96-416 mm2) were treated with arthroscopic excision. Conclusion: Nonoperative treatment in patients with acute calcific tendinitis of the hip joint might be successful in most patients. Surgical treatment is of value for patients experiencing prolonged severe pain, solid type, and large size.
Lumbopelvic Control and Days Missed Because of Injury in Professional Baseball Pitchers
Authors: Chaudhari Ajit M.W. , McKenzie Christopher S. , Pan Xueliang , Oñate James A. 
Published: August 2014

Background: Recently, lumbopelvic control has been linked to pitching performance, kinematics, and loading; however, poor lumbopelvic control has not been prospectively investigated as a risk factor for injuries in baseball pitchers. Hypothesis: Pitchers with poor lumbopelvic control during spring training are more likely to miss ≥30 days because of an injury through an entire baseball season than pitchers with good lumbopelvic control. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 347 professional baseball pitchers were enrolled into the study during the last 2 weeks of spring training and stayed with the same team for the entire season. Lumbopelvic control was quantified by peak anterior-posterior deviation of the pelvis relative to the starting position during a single-leg raise test (APScore). Days missed because of an injury through the entire season were recorded by each team’s medical staff. Results: A higher APScore was significantly associated with a higher likelihood of missing ≥30 days ( P = .023, χ2 test). When divided into tertiles based on their APScore, participants in the highest tertile were 3.0 times and 2.2 times more likely to miss at least 30 days throughout the course of a baseball season relative to those in the lowest or middle tertiles, respectively. A higher APScore was also significantly associated with missing more days because of an injury within participants who missed at least 1 day ( P = .018, ANOVA), with participants in the highest tertile missing significantly more days (mean, 98.6 days) than those in the middle tertile (mean, 45.8 days; P = .017) or lowest tertile (mean, 43.8 days; P = .017). Conclusion: This study found that poor lumbopelvic control in professional pitchers was associated with an increased risk of missing significant time because of an injury.
Carotid atherosclerosis is not associated with lower bone mineral density and vertebral fractures in patients with systemic lupus erythematosus
Authors: Mendoza-Pinto C , García-Carrasco M , Jiménez-Hernández M , Sánchez-Pérez R , Escárcega R O , Nava-Zavala A , Munguía-Realpozo P , López-Colombo A , Jara L J , Cervera R 
Published: August 2014

Background Low bone mineral density (BMD) and vertebral fractures (VF) have been associated with atherosclerosis in the general population. We sought to investigate the relationship between BMD and VF and carotid atherosclerosis in women with systemic lupus erythematosus (SLE). Methods We studied 122 women with SLE. All patients had BMD, carotid intima-media thickness (IMT), and carotid artery atherosclerotic plaque assessment by ultrasound. Results Mean age at study entry was 44 years and mean disease duration was 11 years. Carotid plaque was found in 13 (11%) patients (9 postmenopausal and 4 premenopausal). Patients in the highest IMT quartile were more likely to be older ( p = 0.001), have a higher body mass index ( p = 0.008), and exhibit dyslipidemia at study entry ( p = 0.041), compared with the lower three quartiles. BMD at the lumbar spine was lower in patients in the highest IMT quartile compared with the lower quartiles in the multivariate logistic analysis, however, there was no association between lumbar or total hip BMD and IMT ( p = 0.91 and p = 0.6, respectively). IMT measurements did not differ according to the presence or absence of VF (0.08 ± 0.12 vs. 0.06 ± 0.03 mm, p = 0.11). A trend towards higher incidence of VF was found in patients with carotid plaque compared with those without (33% vs. 21%; p = 0.2). Conclusions In patients with SLE, the presence of carotid atherosclerosis is not associated with low BMD or VF.
Radiation Exposure in Total Ankle Replacement
Authors: Angthong Chayanin , Adams Samuel B. , Easley Mark E. , DeOrio James K. , Nunley James A. 
Published: August 2014

Background: Radiation exposure from diagnostic imaging procedures is associated with increased cancer risk. No published data currently exist regarding ionizing radiation exposure in total ankle replacement surgery. This study quantified intraoperative fluoroscopic dose and duration during ankle replacement surgery and examined patient and technical factors affecting the level of exposure. Methods: Fifty-five patients underwent ankle replacement using STAR, Salto-Talaris, or INBONE total ankles. Intraoperative fluoroscopic dose and duration, patient demographics, implant design, and accompanying additional procedures were documented for each case. The relationship between each relevant variable and radiation dose and time was determined. Results: The mean fluoroscopic dose and duration for all cases were 1.15 ± 0.84 milliGray per case and 77 ± 34 seconds per case, respectively. There was a positive correlation between the absorbed radiation dose and the duration of fluoroscopy ( r = .50, P < .001). The mean fluoroscopic doses were 1.53 milliGray, 0.99 milliGray, and 0.88 milliGray for INBONE, STAR, and Salto-Talaris prostheses, respectively. Fluoroscopic dose was significantly influenced by implant design ( P = .035), with implants using an intramedullary referencing guide associated with higher radiation doses. After excluding cases requiring additional procedures, the fluoroscopic time and radiation dose associated with intramedullary referencing guide implants continued to exceed those of the other implants, but the differences were no longer statistically significant ( P = .22, P = .09, respectively). Conclusion: The average patient radiation dose during total ankle replacement was approximately one-fifth the recommended maximum yearly radiation exposure. The radiation dose was positively associated with fluoroscopy duration. Among factors controllable by the surgeon, selection of an implant with an extramedullary alignment system and conscious effort to minimize duration of fluoroscopy can reduce harmful radiation exposure and decrease cancer risk in total ankle replacement patients and associated operating room personnel. Level of Evidence: Level III, comparative series.