bluuebunny/crossref_metadata_2025 huggingface dataset:
Memory Interference as a Determinant of Language Comprehension
Authors: Van Dyke Julie A. , Johns Clinton L.
Published: March 2012

The parameters of the human memory system constrain the operation of language comprehension processes. In the memory literature, both decay and interference have been proposed as causes of forgetting; however, while there is a long history of research establishing the nature of interference effects in memory, the effects of decay are much more poorly supported. Nevertheless, research investigating the limitations of the human sentence processing mechanism typically focus on decay‐based explanations, emphasizing the role of capacity, while the role of interference has received comparatively little attention. This paper reviews both accounts of difficulty in language comprehension by drawing direct connections to research in the memory domain. Capacity‐based accounts are found to be untenable, diverging substantially from what is known about the operation of the human memory system. In contrast, recent research investigating comprehension difficulty using a retrieval‐interference paradigm is shown to be wholly consistent with both behavioral and neuropsychological memory phenomena. The implications of adopting a retrieval‐interference approach to investigating individual variation in language comprehension are discussed.
Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid–enhanced magnetic resonance imaging predicts the histological grade of hepatocellular carcinoma only in patients with child-pugh class a cirrhosis
Authors: Kim Hee Yeon , Choi Jong Young , Kim Chang Wook , Bae Si Hyun , Yoon Seung Kew , Lee Young Joon , Rha Sung Eun , You Young Kyoung , Kim Dong Goo , Jung Eun Sun
Published: March 2012

The aim of this study was to investigate the role of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)–enhanced magnetic resonance imaging (MRI) in predicting the histological grade of hepatocellular carcinoma (HCC) according to the hepatic function. Eighty-one consecutive patients with 122 histologically proven HCCs who underwent Gd-EOB-DTPA–enhanced MRI before resection (45 HCCs in 42 patients) or transplantation (77 HCCs in 39 patients) were analyzed retrospectively. We calculated the relative enhancement ratios (RER), which is the ratio of the relative intensity of a tumor versus the surrounding parenchyma on hepatobiliary phase images to the relative intensity on unenhanced MRI scans. We then analyzed the correlation between the RER and the tumor differentiation grade in patients with various degrees of hepatic function. The degree of tumor enhancement, which included the precontrast relative intensity ratio (RIR), the postcontrast RIR, and the RER, for well-differentiated (WD) HCCs was significantly higher than the degree of tumor enhancement for moderately differentiated and poorly differentiated (PD) HCCs (P = 0.001 and P = 0.001, respectively, for precontrast RIRs; P < 0.001 and P < 0.001, respectively, for postcontrast RIRs; and P = 0.01 and P = 0.001, respectively, for RERs). In a subgroup analysis based on liver function, the correlation between the histological grade and the enhancement ratio was demonstrated only in the group of patients with Child-Pugh class A cirrhosis. The accuracy of postcontrast RIRs for predicting WD and PD HCCs was favorable; the areas under the receiver operating characteristic curves were 0.896 [95% confidence interval (CI) = 0.817–0.974] and 0.769 (95% CI = 0.658–0.879), respectively. In conclusion, the hepatobiliary phase of Gd-EOB-DTPA–enhanced MRI may help to predict the differentiation of HCCs, especially in HCC patients with Child-Pugh class A cirrhosis before liver transplantation or resection. Liver Transpl, 2012. © 2012 AASLD.
λ‐symmetries, nonlocal transformations and first integrals to a class of Painlevé–Gambier equations
Authors: Yaşar Emrullah
Published: March 2012

In this work, we consider a class of Painlevé–Gambier equations that model the motion of chain ball drawing with constant force in the frictionless surface. λ‐symmetries, first integrals, integrating factors, nonlocal transformations and local transformations are derived by using the some recent studies that are proposed by Muriel and Romero. Copyright © 2012 John Wiley & Sons, Ltd.
Cardiac arterial spin labeling using segmented ECG‐gated Look‐Locker FAIR: Variability and repeatability in preclinical studies
Authors: Campbell‐Washburn Adrienne E. , Price Anthony N. , Wells Jack A. , Thomas David L. , Ordidge Roger J. , Lythgoe Mark F.
Published: March 2012

MRI is important for the assessment of cardiac structure and function in preclinical studies of cardiac disease. Arterial spin labeling techniques can be used to measure perfusion noninvasively. In this study, an electrocardiogram‐gated Look‐Locker sequence with segmented k‐space acquisition has been implemented to acquire single slice arterial spin labeling data sets in 15 min in the mouse heart. A data logger was introduced to improve data quality by: (1) allowing automated rejection of respiration‐corrupted images, (2) providing additional prospective gating to improve consistency of acquisition timing, and (3) allowing the recombination of uncorrupted k‐space lines from consecutive data sets to reduce respiration corruption. Finally, variability and repeatability of perfusion estimation within‐session, between‐session, between‐animal, and between image rejection criteria were assessed in mice. The criterion used to reject images from the T1 fit was shown to affect the perfusion estimation. These data showed that the between‐animal coefficient of variability (24%) was greater than the between‐session variability (17%) and within‐session variability (11%). Furthermore, the magnitude of change in perfusion required to detect differences was 30% (within‐session) and 55% (between‐session) according to Bland‐Altman repeatability analysis. These technique developments and repeatability statistics will provide a platform for future preclinical studies applying cardiac arterial spin labeling. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Muscle fiber velocity and electromyographic signs of fatigue in fibromyalgia
Authors: Klaver‐KrÓl Ewa G. , Rasker Johannes J. , Henriquez Nizare R. , Verheijen Wilma G. , Zwarts Machiel J.
Published: March 2012

Introduction: Fibromyalgia (FM) is a disorder of widespread muscular pain. We investigated possible differences in surface electromyography (sEMG) in clinically unaffected muscle between patients with FM and controls. Methods: sEMG was performed on the biceps brachii muscle of 13 women with FM and 14 matched healthy controls during prolonged dynamic exercises, unloaded, and loaded up to 20% of maximum voluntary contraction. The sEMG parameters were: muscle fiber conduction velocity (CV); skewness of motor unit potential (peak) velocities; peak frequency (PF) (number of peaks per second); and average rectified voltage (ARV). Results: There was significantly higher CV in the FM group. Although the FM group performed the tests equally well, their electromyographic fatigue was significantly less expressed compared with controls (in CV, PF, and ARV). Conclusion: In the patients with FM, we clearly showed functional abnormalities of the muscle membrane, which led to high conduction velocity and resistance to fatigue in electromyography. Muscle Nerve 46: 738–745, 2012
Moth‐eye antireflection coating fabricated by nanoimprint lithography on 1 eV dilute nitride solar cell
Authors: Tommila Juha , Aho Arto , Tukiainen Antti , Polojärvi Ville , Salmi Joel , Niemi Tapio , Guina Mircea
Published: March 2012

We report on the performance of biomimicked antireflection coating applied to dilute nitride solar cell. The coating consists of nanostructures replicating the moth‐eye geometry and has been fabricated by nanoimprint lithography directly within the window layer covering the dilute nitride absorbing junction. The mean reflectivity within the spectral range of 320–1800 nm remains under 5% for incident angles up to 45°. The effect of the coating on the cell performance was assessed by measuring the current–voltage characteristics under simulated solar illumination. A clear performance increase was identified when comparing a solar cell with the moth‐eye coating with a solar cell having a standard SiNx/SiO2 coating. Copyright © 2012 John Wiley & Sons, Ltd.
Mimicking the cell membrane with block copolymer membranes
Authors: Zhang Xiaoyan , Tanner Pascal , Graff Alexandra , Palivan Cornelia G. , Meier Wolfgang
Published: March 2012

Cell membranes are essential barriers in Nature. To understand their properties and functions and to develop desirable applications, a simple and elegant approach is to study membranes that mimic the cell membrane. Lipid bilayers represent simple models that are physiologically representative when in the form of mixtures of various lipids, but they are not adequately stable even when covered with amphipathic proteins or when combined with polymers, thus preventing technological applications. This makes necessary the design of completely synthetic membranes. In this respect, amphiphilic copolymers that self‐assemble under dilute aqueous conditions and generate supramolecular polymer vesicles or films are ideal candidates for synthetic membranes. Their versatility in terms of chemistry and properties (permeability, mechanical stability, thickness), if appropriately designed, enable the insertion of biological molecules, such as membrane proteins and biopores, or the attachment of biomolecules at their surfaces. Here, we present the domain of synthetic membranes based on amphiphilic copolymers beginning with their generation and up to their applications in medicine, the food industry, and technology. Even though significant progress has been made in combining them with membrane proteins, open questions remain with respect to desired properties that could accommodate biological molecules and support further development of the field, from both the point of view of fundamental understanding and of applications. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Methylol‐functional benzoxazines as precursors for high‐performance thermoset polymers: Unique simultaneous addition and condensation polymerization behavior
Authors: Baqar Mohamed , Agag Tarek , Ishida Hatsuo , Qutubuddin Syed
Published: March 2012

A new class of high‐performance resins of combined molecular structure of both traditional phenolics and benzoxazines has been developed. The monomers termed as methylol‐functional benzoxazines were synthesized through Mannich condensation reaction of methylol‐functional phenols and aromatic amines, including methylenedianiline (4,4′‐diaminodiphenylmethane) and oxydianiline (4,4′‐diaminodiphenyl ether), in the presence of paraformaldehyde. For comparison, other series of benzoxazine monomers were prepared from phenol, corresponding aromatic amines, and paraformaldehyde. The as‐synthesized monomers are characterized by their high purity as judged from 1H NMR and Fourier transform infrared spectra. Differential scanning calorimetric thermograms of the novel monomers show two exothermic peaks associated with condensation reaction of methylol groups and ring‐opening polymerization of benzoxazines. The position of methylol group relative to benzoxazine structure plays a significant role in accelerating polymerization. Viscoelastic and thermogravimetric analyses of the crosslinked polymers reveal high Tg (274–343 °C) and excellent thermal stability when compared with the traditional polybenzoxazines. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
One‐pot synthesis of hyperbranched glycopolymers by RAFT polymerization
Authors: Wei Zhenke , Hao Xiaojuan , Gan Zhihua , Hughes Timothy C.
Published: March 2012

Soluble hyperbranched glycopolymers were prepared by copolymerization of glycan monomers with reversible addition‐fragmentation chain transfer polymerization (RAFT) inimers in a simple one‐pot reaction. Two novel RAFT inimers, 2‐(methacryloyloxy)ethyl 4‐cyano‐4‐(phenylcarbonothioylthio)pentanoate (MAE‐CPP) and 2‐(3‐(benzylthiocarbonothioylthio)propanoyloxy)ethyl acrylate (BCP‐EA) were synthesized and used to prepare hyperbranched glycopolymers. Two types of galactose‐based saccharide monomers, 6‐O‐methacryloyl‐1,2:3,4‐di‐O‐isopropylidene‐D‐galactopyranose (proGal‐M) and 6‐O‐(2′‐acrylamido‐2′‐methylpropanoate)‐1,2:3,4‐di‐O‐isopropylidene‐D‐galactopyranose (proGal‐A), containing a methacrylate and an acrylamide group, respectively, were also synthesized and polymerized under the mediation of the MAE‐CPP and BCP‐EA inimers, respectively. In addition, hyperbranched poly(proGal‐M), linear poly(proGal‐A), and hyperbranched poly(proGal‐A) were generated and their polymerization kinetics were studied and compared. An unexpected difference was observed in the kinetics between the two monomers during polymerization: the relationship between polymerization rate and concentration of inimer was totally opposite in the two monomer–inimer systems. Branching analysis was conducted by using degree of branching (DB) as the measurement parameter. As expected, a higher DB occurred with increased inimer content. Furthermore, these polymers were readily deprotected by hydrolysis in trifluoroacetic acid solution resulting in water‐soluble polymers. The resulting branched glycopolymers have potential as biomimetics of polysaccharides. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Photoinitiated RAFT polymerization of vinyl acetate
Authors: Ham Min‐kyoung , HoYouk Ji , Kwon Yong‐Ku , Kwark Young‐Je
Published: March 2012

A photoinitiation process was investigated to develop a rapid and well‐controlled RAFT polymerization method applied to vinyl acetate (VAc) using methyl (ethoxycarbonothioyl)sulfanyl acetate (MESA) and bis(2,4,6‐trimethylbenzoyl)phenylphosphine oxide as the RAFT agent and photoinitiator, respectively. MESA was selected as the photochemically inert RAFT agent to minimize photolysis of the thiocarbonylthio groups during polymerization. Poly(vinyl acetate) with a prespecified well‐controlled molecular weight (MW) and a narrow MW distribution was successfully synthesized. The polymerization reaction proceeded as a living polymerization and was remarkably rapid compared with approaches that use thermally initiated processes with a very short induction period. A detailed kinetic study of the mechanism underlying the polymerization reaction, however, revealed that the chain ends containing xanthate moieties were not perfectly stable upon UV‐irradiation, and they generated radicals via homolytic cleavage. This reaction appeared to proceed by a combination of a degenerative transfer RAFT mechanism and a dissociation‐combination mechanism. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Glu121‐Lys319 salt bridge between catalytic and N‐terminal domains is pivotal for the activity and stability of Escherichia coli aminopeptidase N
Authors: Gumpena Rajesh , Kishor Chandan , Ganji Roopa Jones , Jain Nishant , Addlagatta Anthony
Published: March 2012

Escherichia coli aminopeptidase N (ePepN) belongs to the gluzincin family of M1 class metalloproteases that share a common primary structure with consensus zinc binding motif (HEXXH‐(X18)‐E) and an exopeptidase motif (GXMEN) in the active site. There is one amino acid, E121 in Domain I that blocks the extended active site grove of the thermolysin like catalytic domain (Domain II) limiting the substrate to S1 pocket. E121 forms a part of the S1 pocket, while making critical contact with the amino‐terminus of the substrate. In addition, the carboxylate of E121 forms a salt bridge with K319 in Domain II. Both these residues are absolutely conserved in ePepN homologs. Analogous Glu‐Asn pair in tricon interacting factor F3 (F3) and Gln‐Asn pair in human leukotriene A4 hydrolase (LTA4H) are also conserved in respective homologs. Mutation of either of these residues individually or together substantially reduced or entirely eliminated enzymatic activity. In addition, thermal denaturation studies suggest that the mutation at K319 destabilizes the protein as much as by 3.7°C, while E121 mutants were insensitive. Crystal structure of E121Q mutant reveals that the enzyme is inactive due to the reduced S1 subsite volume. Together, data presented here suggests that ePepN, F3, and LTA4H homologs adopted a divergent evolution that includes E121‐K319 or its analogous pairs, and these cannot be interchanged.
The folding pathway of glycosomal triosephosphate isomerase: Structural insights into equilibrium intermediates
Authors: Guzman‐Luna Valeria , Garza‐Ramos Georgina
Published: March 2012

The guanidine hydrochloride‐induced conformational transitions of glycosomal triosephosphate isomerase (TIM) were monitored with functional, spectroscopic, and hydrodynamic measurements. The equilibrium folding pathway was found to include two intermediates (N2↔I2↔2M↔2U). According to this model, the conformational stability parameters of TIM are as follows: ΔGI2‐N2 = 5.5 ± 0.6, ΔG2M‐I2=19.6 ± 1.6, and ΔG2U‐2M = 14.7 ± 3.1 kcal mol−1. The I2 state is compact (αSR = 0.8); it is able to bind 8‐anilinonaphthalene‐1‐sulfonic acid ANS and it is composed of ∼45% of α‐helix and tertiary structure content compared with the native enzyme; however, it is unable to bind the transition‐state analog 2‐phosphoglycolate. Conversely, the 2M state lacks detectable tertiary contacts, possesses ∼10% of the native α‐helical content, is significantly expanded (αSR = 0.2), and has low affinity for ANS. We studied the effect of mutating cysteine residues on the structure and stability of I2 and 2M. Three mutants were made: C39A, C126A, and C39A/C126A. The replacement of C39, which is located at β2, was found to be neutral. The I2–C126A state, however, was prone to aggregation and exhibited an emission maximum that was 3‐nm red‐shifted compared with the I2–wild type, indicating solvent exposure of W90 at β4. Our results suggest that the I2 state comprises the (βα)1‐4β5 module in which the conserved C126 residue located at β5 defines the boundary of the folded segment. We propose a folding pathway that highlights the remarkable thermodynamic stability of this glycosomal enzyme. Proteins 2012; © 2012 Wiley Periodicals, Inc.
First‐principles calculations of spontaneous polarization for TTF‐QBrCl3
Authors: Ishibashi Shoji , Horiuchi Sachio , Kumai Reiji , Terakura Kiyoyuki
Published: March 2012

We have evaluated spontaneous polarization for TTF‐QBrCl3, whose crystal structure is similar to that of TTF‐CA, by first‐principles calculations. The obtained results are compared with those for closely related materials TTF‐CA and TTF‐BA and found to have some similarities to those for TTF‐CA. No magnetic state is found and polarization grows non‐linearly with the adiabatic switching parameter λ when the system varies from the virtual paraelectric state to the actual ferroelectric state. The evaluated spontaneous polarization values are in the same range as the experimental ones.
RECRUITMENT AND SUCCESSIONAL DYNAMICS DIVERSIFY THE SHIFTING HABITAT MOSAIC OF AN ALASKAN FLOODPLAIN
Authors: Mouw J. E.B. , Chaffin J. L. , Whited D. C. , Hauer F. R. , Matson P. L. , Stanford J. A.
Published: March 2012

We measured plant recruitment patterns, successional dynamics, and biophysical processes on laterally expansive floodplains of the Kwethluk River, Alaska. The main channel of this gravel‐bed river frequently avulses and possesses an anabranching plan form. Fluvial processes were interactive with life history processes of riparian plants in determining initial stages of primary succession. Reproductive strategies and herbivory became important factors later in succession. We conducted plant age and compositional surveys to assess patterns of propagule deposition. We found that dispersal strategies of species were an important factor influencing recruitment patterns. Flood‐dispersed seeds resulted in even‐aged cohorts of species persistently segregated in space, based on age data. Sediment characteristics and inundation potential had little influence on seedling distributions. Recruitment was also segregated on the basis of dispersal strategy. At the heads of bars, where vegetative propagules (live drift wood) were entombed during floods, the distributions of species were random. This size‐selective nature of recruitment persisted through time. Vegetation age and distribution patterns were further diversified by the river's legacy of gravel deposition that diversified the primary successional pathway: one associated with ridges and another with swales. Interactions between these pathways and beaver herbivory initiated secondary succession. We used satellite imagery to quantify the extent of floodplain influenced by herbivory and to assess the importance of this driver of secondary succession. We also used high‐resolution aerial imagery and randomly selected sites to provide an unbiased analysis. We classified this imagery to quantify the spatial extent of herbivory and its influence on the initiation of secondary succession. The results showed, in addition to recruitment and successional dynamics, the flood‐plain habitat mosaic was diversified by the initiation of secondary succession. Patch and species composition within the vegetation mosaics were significantly different than those portions of the floodplain engaged in primary succession. Copyright © 2012 John Wiley & Sons, Ltd.
Phenomenology and cosmology of an electroweak pseudo-dilaton and electroweak baryons
Authors: Campbell Bruce A. , Ellis John , Olive Keith A.
Published: March 2012

Abstract

In many strongly-interacting models of electroweak symmetry breaking the lowest-lying observable particle is a pseudo-Goldstone boson of approximate scale symmetry, the pseudo-dilaton. Its interactions with Standard Model particles can be described using a low-energy effective nonlinear chiral Lagrangian supplemented by terms that restore approximate scale symmetry, yielding couplings of the pseudo-dilaton that differ from those of a Standard Model Higgs boson by fixed factors. We review the experimental constraints on such a pseudo-dilaton in light of new data from the LHC and elsewhere. The effective nonlinear chiral Lagrangian has Skyrmion solutions that may be identified with the ‘electroweak baryons’ of the underlying strongly-interacting theory, whose nature may be revealed by the properties of the Skyrmions. We discuss the finite-temperature electroweak phase transition in the low-energy effective theory, finding that the possibility of a first-order electroweak phase transition is resurrected. We discuss the evolution of the Universe during this transition and derive an order-of-magnitude lower limit on the abundance of electroweak baryons in the absence of a cosmological asymmetry, which suggests that such an asymmetry would be necessary if the electroweak baryons are to provide the cosmological density of dark matter. We revisit estimates of the corresponding spin-independent dark matter scattering cross section, with a view to direct detection experiments.
Primary Blast Injuries—An Updated Concise Review
Authors: Yeh Daniel Dante , Schecter William P.
Published: March 2012

Blast injuries have been increasing in the civilian setting and clinicians need to understand the spectrum of injury and management strategies. Multisystem trauma associated with combined blunt and penetrating injuries is the rule. Explosions in closed spaces increase the likelihood of primary blast injury. Rupture of tympanic membranes is an inaccurate marker for severe primary blast injury. Blast lung injury manifests early and should be managed with lung‐protective ventilation. Blast brain injury is more common than previously appreciated.
Subcuticular Absorbable Suture with Subcutaneous Drainage System Prevents Incisional SSI after Hepatectomy for Hepatocellular Carcinoma
Authors: Tsujita Eiji , Yamashita Yo‐ichi , Takeishi Kazuki , Matsuyama Ayumi , Tsutsui Shin‐ichi , Matsuda Hiroyuki , Taketomi Akinobu , Shirabe Ken , Ishida Teruyoshi , Maehara Yoshihiko
Published: March 2012

Background

The effectiveness of subcuticular absorbable suture with subcutaneous drainage to decrease the risk of postoperative incisional surgical site infection (SSI) in hepatocellular carcinoma (HCC) patients was evaluated.

Methods

A total of 149 patients with HCC who underwent hepatectomy (Hx) were retrospectively investigated. Patients were divided into two groups: the patients with subcuticular suture combined with subcutaneous drainage (the drainage group; 61 patients) and the patients with nylon suture without subcutaneous drainage (the nylon group; 88 patients). After the operations, the complication rate of postoperative incisional SSI was analyzed and compared between the two groups.

Results

In the drainage group the rate of incisional SSI was significantly lower compared to the nylon group: 14–3 % (p = 0.033), respectively. Patients with incisional SSI needed significantly longer postoperative hospital care than the patients without incisional SSI: 28 versus 15 days (p < 0.005). Multivariate analysis revealed that subcuticular absorbable suture with subcutaneous drainage significantly reduced the occurrence of incisional SSI (odds ratio; 0.15; p = 0.034).

Conclusions

We have demonstrated that the subcuticular suture with subcutaneous drainage is effective in preventing incisional SSI in patients undergoing Hx for HCC.
Double Omental Flap Reduced Perianastomotic Collections and Relaparotomy Rates after Pancreaticoduodenectomy with Pancreaticogastrostomy
Authors: Rosso Edoardo , Lopez Patricia , Roedlisch Marie Noel , Narita Masato , Oussoultzoglou Elie , Bachellier Philippe
Published: March 2012

Introduction

In an attempt to reduce the perioperative morbidity after pancreaticoduodenectomy, the results of double omental flap (DOF) after pancreaticoduodenectomy (PD) with pancreaticogastrostomy (PG) were compared to a standard technique.

Methods

From January 2009 to December 2009, 61 patients underwent PD with PG for pancreatic adenocarcinoma in our department. Perioperative data were prospectively recorded, and postoperative outcome of patients who underwent or not a DOF (group DOF+ = 33 and group DOF− = 28, respectively) was analyzed.

Results

The overall postoperative mortality was 1.6 % (n = 1). The overall postoperative morbidity rate was 27.8 % (n = 17). PF occurred in eight (13.1 %) patients and was grade A in six (9.8 %) patients. Clinically relevant PF (grade B and C) occurred in two (3.2 %) patients. The univariate analysis showed that in the DOF+ groups there was a significant reduction of perianastomotic collections (P = 0.034) and a significant reduction of the relaparotomy rate (P = 0.05).

Discussion

The DOF contributed to reduce the rate of perianastomotic collections as well as the rate of relaparotomy.

Conclusions

A DOF should be considered a further step toward a reduction of surgical‐related complications after PD with PG.
Laparoscopic Appendectomy Outcomes on the Weekend and During the Week are no Different: A National Study of 151,774 Patients
Authors: Worni Mathias , Østbye Truls , Gandhi Mihir , Rajgor Dimple , Shah Jatin , Shah Anand , Pietrobon Ricardo , Jacobs Danny O. , Guller Ulrich
Published: March 2012

Background

The “weekend effect” is defined as increased morbidity and mortality for patients admitted on weekends compared with weekdays. It has been observed for several diseases, including myocardial infarction and renal insufficiency; however, it has not yet been investigated for laparoscopic appendectomy in acute appendicitis—one of the most prevalent surgical diagnoses.

Methods

The present study is based on the Nationwide Inpatient Sample (NIS) from 1999 to 2008. The following outcomes were compared between patients undergoing laparoscopic appendectomy for acute appendicitis admitted on weekdays versus weekends: severity of appendicitis, intraoperative and postoperative complications, conversion rate, in‐hospital mortality, and length of hospital stay. Unadjusted and risk‐adjusted generalized linear regression analyses were performed.

Results

Overall, 151,774 patients were included, mean age was 39.6 years, 52.6% (n = 79,801) were male, and 25.3% (n = 38,317) were admitted on weekends. After risk adjustment, the conversion rate was lower [odds ratio (OR): 0.94, p = 0.004, number needed to harm (NNH): 244], whereas pulmonary complications (OR: 1.12, p = 0.028, NNH: 649) and reoperations (OR: 1.21, p = 0.013, NNH: 1,028) were slightly higher on weekends than on weekdays. Overall postoperative complications (OR: 1.03, p = 0.24), mortality (OR: 1.37, p = 0.075) and length of hospital stay (mean on weekday: 2.00 days, weekends: 2.01 days, p = 0.29) were not statistically different.

Conclusions

The present investigation provides evidence that no clinically significant “weekend effect” for patients undergoing laparoscopic appendectomy exists. Therefore, hospital or staffing policy changes are not justified based on the findings from this large national study.
Evidence of serologic activity in chronic hepatitis B after surface antigen (HBsAg) seroclearance documented by conventional HBsAg assay
Authors: Seto Wai-Kay , Tanaka Yasuhito , Wong Danny Ka-Ho , Lai Ching-Lung , Shinkai Noboru , Yuen John Chi-Hang , Tong Teresa , Fung James , Hung Ivan Fan-Ngai , Yuen Man-Fung
Published: March 2012

Background

Possible serologic activity after hepatitis B surface antigen (HBsAg) seroclearance documented by conventional assays in chronic hepatitis B (CHB) has not been thoroughly investigated.

Methods

We determined the levels of serum hepatitis B virus (HBV) DNA, hepatitis B core-related antigen (HBcrAg), and linearized HBsAg (CLEIA prototype) in 329 CHB patients (72.0% male) after HBsAg seroclearance was documented by a conventional HBsAg assay.

Results

The median interval between presentation and HBsAg seroclearance was 69.4 months. The median age at HBsAg seroclearance was 50 years. Assays for serum HBV DNA, HBcrAg, and linearized HBsAg were performed at a median time interval of 11.2 months after HBsAg loss. Linearized HBsAg and HBcrAg were detectable in 85 (25.8%) and 69 (21%) patients, respectively, and one or both serologic markers were detectable in 133 patients (40.4%). Serum HBV DNA was detectable in only 7 patients (2.1%). There was no correlation between linearized HBsAg and HBcrAg levels (r = 0.095, p = 0.924). The incidences of detectable linearized HBsAg and HBcrAg did not differ between patient samples taken at 6–12 and >12 months after HBsAg seroclearance (p = 0.146 and 0.079, respectively). Among patients with detectable serologic markers, median levels of linearized HBsAg (p = 0.581) and HBcrAg (p = 0.951) did not significantly change with time after HBsAg seroclearance.

Conclusion

Using novel HBcrAg and linearized HBsAg assays, viral serologic activity after HBsAg seroclearance was demonstrated in more than 40% of CHB patients. These tests have potential applications in diagnosing and prognosticating CHB patients with HBsAg seroclearance.
Singleton pregnancy outcomes after assisted and non‐assisted reproductive technology in infertile patients
Authors: Tsutsumi Ryo , Fujimoto Akihisa , Osuga Yutaka , Ooi Nagisa , Takemura Yuri , Koizumi Minako , Yano Tetsu , Taketani Yuji
Published: March 2012

Purpose

Singleton pregnancy after assisted reproductive technology (ART) has been associated with higher risks of adverse pregnancy outcome than naturally conceived singleton pregnancy. This study was to elucidate whether the ART procedure is responsible for abnormal pregnancy outcome comparing those after ART and non‐ART in infertile patients.

Methods

We compare the singleton pregnancy outcome of infertile patients in our university hospital between 2000 and 2008 following ART (351 pregnancies) and non‐ART (213 pregnancies) procedures. Pregnancy outcome parameters were incidence of pregnancy induced hypertension, placenta previa, placental abruption, cesarean delivery, preterm birth, very preterm birth, stillbirth, low birth weight and very low birth weight.

Results

Most of the pregnancy outcome parameters were not significantly different between the ART group and the non‐ART group. Only placenta previa was significantly higher in the ART group than in the non‐ART group (odds ratio 4.0; 95 % CI 1.2–13.7).

Conclusions

ART procedure may itself be a risk factor for the development of placenta previa. Some of the abnormal perinatal outcomes that had been previously attributed to ART, however, may be due to the baseline characteristics of infertile patients.
Go North, Young Scholar, Go North
Authors: White Graham
Published: March 2012

Abstract.The North—defined as the Canadian Arctic—ranks among the most understudied and yet the most promising fields of enquiry for Canadian political scientists. It offers a host of fascinating research topics and intellectual puzzles, many of which entail the often fraught relationship between the Canadian state and Aboriginal peoples. Important conceptual issues await academics studying northern politics and governance. As well, political scientists' work can benefit the governments and the people of the North who are grappling with difficult practical problems as they develop distinctive ways of governing themselves.

Academic work on northern politics can be at once intellectually stimulating, professionally rewarding and of significant practical utility. Accordingly, more Canadian political scientists, especially young scholars, should turn their attention northwards.

Résumé.Le Nord, ou plus précisément l'Arctique canadien, constitue un des champs les moins explorés et pourtant les plus prometteurs pour les politologues canadiens. Son étude révèle une foule de sujets de recherche fascinants et d'énigmes intellectuelles, dont plusieurs se rapportent aux relations souvent tendues entre l'État canadien et les peuples autochtones. D'importants enjeux conceptuels se posent aux chercheurs de la politique nordique et de la gouvernance. De plus, les recherches des politologues peuvent aider les gouvernements et les habitants du Nord à résoudre des problèmes concrets associés au développement de façons distinctives de se gouverner.

En somme, la recherche sur la politique nordique peut être à la fois intellectuellement stimulante, professionnellement gratifiante et pourvu d'une grande utilité pratique. En conséquence, plus de politologues canadiens, et en particulier ceux des nouvelles générations, devraient diriger leur attention vers le Nord.
Young Canadians in the 2008 Federal Election Campaign: Using Facebook to Probe Perceptions of Citizenship and Participation
Authors: Goodman Nicole , Bastedo Heather , LeDuc Lawrence , Pammett Jon H.
Published: March 2012

Abstract.The gradual withdrawal of young voters from the active electorate is one of the strongest and most important factors in accounting for declining voter turnout in Canada and other western democracies. Because qualitative approaches may be better able to probe the reasons underlying these changing values and attitudes than traditional mass surveys, we used the popular social media site Facebook during the 2008 federal election campaign to collect data on young people's perceptions of electoral politics in the context of their civic obligations. This medium proved to be a valuable and productive research tool. Based on this project, we argue that non-voting tends to be seen as a more socially acceptable behaviour to young voters than is typically found in the thinking of older cohorts, and that this may be connected to changing concepts of the obligations of citizenship.

Résumé.Le désengagement graduel des jeunes électeurs est un des facteurs les plus importants pour expliquer le déclin de la participation électorale au Canada et dans les démocraties occidentales. Afin de mieux comprendre les causes de ce changement de valeurs et d'attitudes, nous avons utilisé le média socialFacebookafin de collecter des données qualitatives sur la perception des jeunes électeurs durant l'élection fédérale de 2008. Cette approche nous apparaît mieux adapter que l'approche traditionnelle caractérisée par l'utilisation de sondages d'opinion. Au terme de l'analyse, la collecte de données viaFacebooks'est avérée être une stratégie de recherche productive. En nous basant sur ces données, nous concluons que l'abstention électorale est un comportement plus socialement acceptable pour les jeunes électeurs que pour les électeurs plus âgés. Cette attitude pourrait être liée un changement conceptuel quant aux obligations associées à la citoyenneté.
Vers une bureaucratie représentative. La promotion de la représentation et de la diversité linguistiques dans l'administration fédérale en Suisse et au Canada
Authors: Kübler Daniel , Kobelt Émilienne , Andrey Stephanie
Published: March 2012

Résumé.Sous l'angle du concept de bureaucratie représentative, le présent article compare la gestion des enjeux liés à la participation des différentes communautés linguistiques dans l'administration publique de deux États multilingues : le Canada et la Suisse. À la suite de la mobilisation politique autour du clivage linguistique, des stratégies de promotion du plurilinguisme ont été adoptées dans les deux pays. La stratégie canadienne mise surl'égalité de traitementdes fonctionnaires anglophones et francophones. La Suisse poursuit quant à elle l'objectif de lareprésentationdes différentes communautés linguistiques dans la fonction publique. Ces différences de fond s'expliquent, entre autres, par la nature du régime linguistique en place et par le contexte de démocratie consociationnelle en Suisse. La participation proportionnelle des communautés linguistiques au sein de l'administration fédérale est globalement atteinte dans les deux pays. Cependant, au niveau du fonctionnement interne, une logique de rationalité linguistique exerce une pression sur les groupes minoritaires pour qu'ils adoptent la langue majoritaire.

Abstract.Drawing on the concept of representative bureaucracy, this article examines how two multi-lingual states—Canada and Switzerland—deal with issues related to the participation of different linguistic communities in the federal public service. Following a political mobilisation of the linguistic cleavage, strategies to promote multilingualism in the public service have been adopted in both countries. The Canadian strategy focuses onequal treatmentof Anglophones and Francophones in the public service. In Switzerland,adequate representationof the linguistic communities is the primary goal. These differences are explained by the characteristics of the linguistic regimes in each of the two countries, as well as by the peculiarities of consociational democracy in Switzerland. In both countries, the linguistic origins of public administration staff, overall, mirrors the proportions of the linguistic communities in the wider society. Within administrative units, however, linguistic diversity is hampered by the logics of language rationality, where minorities are under pressure to communicate in the language of the majority.
Effects of age and species on agronomic performance, chemical composition and in vitro gas production of some tropical multi-purpose tree species
Authors: ARIGBEDE O. M. , TAN Z. L. , ANELE U. Y. , SUN Z. H. , TANG S. X. , HAN X. F. , ZHOU C. S. , ZENG B.
Published: March 2012

Five tropical multi-purpose tree species (MPTS), Enterolobium cyclocarpum, Moringa oleifera, Millettia griffoniana, Pterocarpus santalinoides and Treculia Africana, and one exotic species (Leucaena leucocephala), which acted as the control, planted in a randomized complete block design, were selected to evaluate the potentials as feed supplements for herds in dry seasons of south-western Nigeria. Samples of the MPTS leaves were collected in 2005, 2006, 2007 and 2008, weighed, dried and milled for estimation of biomass production, chemical analysis and measurement of in vitro gas production. Results showed significant differences (P < 0·001) in the biomass production of the MPTS. E. cyclocarpum consistently recorded the highest biomass production, height and collar diameter throughout the experimental period. There were also differences (P ⩽ 0·001) in dry matter (DM), crude protein (CP), ether extract (EE) and ash contents of the MPTS across species and years after planting. M. oleifera recorded the highest CP content of 240 g/kg DM. Interactions were observed between species and year for neutral detergent fibre (NDFom), acid detergent fibre (ADFom) and lignin contents of the MPTS. M. griffoniana and M. oleifera had lower tannin contents, whereas E. cyclocarpum, P. santalinoides, T. africana and L. leucocephala had higher tannin contents. The values reported for mineral contents showed that their levels in the MPTS were adequate for ruminants and there were no differences in the contents of most minerals. In vitro gas production results showed that the potential gas production ‘b’ was highest in M. griffoniana and lowest in P. santalinoides and there were species and year interactions (P ⩽ 0·001) for volatile fatty acid profiles of the supernatant after 96 h incubation. The estimated organic matter digestibility (OMD) and metabolizable energy (ME) of the MPTS were generally high. The high biomass production, CP and low fibre contents, as well as in vitro fermentation characteristics found for the MPTS evaluated in the current study suggest that these are better alternatives in comparison with L. leucocephala. It can be concluded that the MPTS evaluated have potential as sources of feed supplements for ruminants in dry seasons, especially in south western Nigeria.
Industrialization and Fertility in the Nineteenth Century: Evidence from South Carolina
Authors: WANAMAKER MARIANNE H.
Published: March 2012

Economists frequently hypothesize that industrialization contributed to the United States’ nineteenth-century fertility decline. I exploit the circumstances surrounding industrialization in South Carolina between 1881 and 1900 to show that the establishment of textile mills coincided with a 6–10 percent fertility reduction. Migrating households are responsible for most of the observed decline. Higher rates of textile employment and child mortality for migrants can explain part of the result, and I conjecture that an increase in child-raising costs induced by the separation of migrant households from their extended families may explain the remaining gap in migrant-native fertility.
Vowel spaces in Plains Cree
Authors: Muehlbauer Jeffrey
Published: March 2012

This paper presents a pilot study of the acoustic correlates of the Plains Cree vowel system. Naturalistic recordings of speakers of mid-20th-century Plains Cree, including one monolingual speaker, provide an empirical test for the general expectations from phonological descriptions. The results demonstrate that, while the hypothesized short/long vowel pairs do indeed have a strong durational contrast, the majority of vowel pairs are also distinguished by their formants. In all cases, the long vowel occupies a more extreme position in the vowel space. Plains Cree thus appears to show both a quantity and a quality contrast in its vowel pairs. The individual speaker data are then normalized to test whether there is intra-speaker variation in these results, with the results showing variation in the relation between vowels in all three parts of the vowel space.
Investigating the nature of aspirated stops in Western Andalusian Spanish
Authors: Torreira Francisco
Published: March 2012

In Western Andalusian Spanish (WAS), [h + voiceless stop] clusters are realized as long pre- and postaspirated stops. This study investigates if a new class of stops (realized as geminates with variable degrees of pre- and postaspiration) has emerged in this dialect, or if postaspiration in these clusters results from articulatory overlap. An experiment was carried out in which WAS speakers produced [h + voiceless stop] clusters under changes in speech rate and stress location. The duration of postaspiration, measured as voice onset, did not show systematic effects of any of the experimental variables. Moreover, trade-offs were observed between voice onset and preaspiration plus closure durations. These results indicate that postaspiration in WAS [h + voiceless stop] clusters is the consequence of extensive articulatory overlap. It is further hypothesized that the lengthening of closures in WAS stops preceded by [h] results from a different gestural mechanism affecting all [hC] clusters in this dialect. From a broader perspective, since extensive overlap and consonantal lengthening do not occur in the [hC] clusters of other Spanish varieties, these findings lend support to the idea that intergestural coordination patterns can be dialect-specific.
‘Do you own non-Chinese mui tsai?’ Re-examining Race and Female Servitude in Malaya and Hong Kong, 1919–1939
Authors: LEOW RACHEL
Published: March 2012

This paper considers the abolition of the mui tsai (young female bondservants) as it unfolded in British Malaya, and challenges the overemphasis on Hong Kong as the primary focus of mui tsai scholarship. While the mui tsai system was defended as a time-honoured Chinese tradition, this paper uses new material to show that trans-racial considerations figured prominently in mui tsai abolition in Malaya, particularly in helping to recast it as a wider problem of child welfare. It is argued that this neglected aspect of mui tsai abolition only comes clearly to light in the Malayan case; for only in the intensely multi-racial conditions of peninsular Malaya could the question be asked: ‘Do you own non-Chinese mui tsai?’
Hebrew School in Nineteenth-Century Bombay: Protestant Missionaries, Cochin Jews, and the Hebraization of India's Bene Israel Community
Authors: NUMARK MITCH
Published: March 2012

This paper is a study of cultural interaction and diffusion in colonial Bombay. Focusing on Hebrew language instruction, it examines the encounter between India's little-known Bene Israel Jewish community and Protestant missionaries. Whilst eighteenth and nineteenth-century Cochin Jews were responsible for teaching the Bene Israel Jewish liturgy and forms of worship, the Bene Israel acquired Hebrew and Biblical knowledge primarily from nineteenth-century Protestant missionaries. At the beginning of the nineteenth century, the Bene Israel community was a Konkanjatiwith limited knowledge of Judaism. However, by the end of the century the community had become an Indian-Jewish community roughly analogous to other Jewish communities. This paper explores how this transformation occurred, detailing the content, motivation, and means by which British and American missionaries and, to a lesser extent, Cochin Jews instructed the Bene Israel in Jewish knowledge. Through a critical examination of neglected English and Marathi sources, it reconstructs the Bene Israel perspective in these encounters and their attitude towards the Christian missionaries who laboured amongst them. It demonstrates that the Bene Israel were active participants and selective consumers in their interaction with the missionaries, taking what they wanted most from the encounter: knowledge of the Old Testament and the Hebrew language. Ultimately, the instruction the Bene Israel received from Protestant missionaries did not convert them to Christianity but strengthened and transformed their Judaism.