bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of perioperative chemotherapy on oncological outcomes after gastric cancer surgery
Authors: Bringeland E A , Wasmuth H H , Fougner R , Mjønes P , Grønbech J E
Published: October 2014

Background

Perioperative chemotherapy has become standard care for resectable gastric cancer. However, available evidence is based on a limited number of trials, and the outcomes in routine clinical practice and in unselected patients are scarcely reported.

Methods

The study included a consecutive series of patients with resectable gastric cancer treated between 2001 and 2011 in Central Norway. Before 2007, patients with resectable gastric cancer did not receive perioperative chemotherapy. Since 2007, medically fit patients with resectable gastric cancer and aged 75 years or less have been offered this. Response rates were evaluated by CT, and tolerability was assessed by the frequency of hospital admission, need for dose reduction or treatment discontinuation. The two time intervals were compared on an intention-to-treat basis for patients aged no more than 75 years for any impact on resection rates, surgical morbidity, postoperative mortality and long-term survival.

Results

About two-thirds (259) of the 419 patients registered were aged 75 years or less at diagnosis. Ninety-five of 136 patients in the later interval were eligible for chemotherapy, of whom 90 actually received the specified regimen, and 78 (87 per cent) were able to complete the preoperative course. Only 40 (44 per cent) completed all scheduled preoperative and postoperative cycles. Thirty-eight (43 per cent) of 89 evaluable patients showed a definite response on CT. Chemotherapy had no impact on postoperative morbidity or mortality. The 5-year survival rate on an intention-to-treat basis was 40·7 (95 per cent c.i. 30·7 to 50·7) per cent in the first interval, compared with 41·7 (31·5 to 51·9) per cent after the introduction of perioperative chemotherapy (P = 0·765). After adjustment for other risk factors, based on comparisons of the two time intervals, there were no differences in oncological outcomes with the use of perioperative chemotherapy.

Conclusion

Perioperative chemotherapy was completed in less than half of the patients with resectable gastric cancer. An observed tumour response to chemotherapy did not translate into any long-term survival benefit compared with surgery alone.
A composite Bayesian hierarchical model of compositional data with zeros
Authors: Napier Gary , Neocleous Tereza , Nobile Agostino
Published: October 2014

We present an effective approach for modelling compositional data with large concentrations of zeros and several levels of variation, applied to a database of elemental compositions of forensic glass of various use types. The procedure consists of the following: (i) partitioning the data set in subsets characterised by the same pattern of presence/absence of chemical elements and (ii) fitting a Bayesian hierarchical model to the transformed compositions in each data subset. We derive expressions for the posterior predictive probability that newly observed fragments of glass are of a certain use type and for computing the evidential value of glass fragments relating to two competing propositions about their source. The model is assessed using cross‐validation, and it performs well in both the classification and evidence evaluation tasks. Copyright © 2014 John Wiley & Sons, Ltd.
A Covalent Organic Framework–Cadmium Sulfide Hybrid as a Prototype Photocatalyst for Visible‐Light‐Driven Hydrogen Production
Authors: Thote Jayshri , Aiyappa Harshitha Barike , Deshpande Aparna , Díaz Díaz David , Kurungot Sreekumar , Banerjee Rahul
Published: October 2014

CdS nanoparticles were deposited on a highly stable, two‐dimensional (2D) covalent organic framework (COF) matrix and the hybrid was tested for photocatalytic hydrogen production. The efficiency of CdS‐COF hybrid was investigated by varying the COF content. On the introduction of just 1 wt % of COF, a dramatic tenfold increase in the overall photocatalytic activity of the hybrid was observed. Among the various hybrids synthesized, that with 10 wt % COF, named CdS‐COF (90:10), was found to exhibit a steep H2 production amounting to 3678 μmol h−1 g−1, which is significantly higher than that of bulk CdS particles (124 μmol h−1 g−1). The presence of a π‐conjugated backbone, high surface area, and occurrence of abundant 2D hetero‐interface highlight the usage of COF as an effective support for stabilizing the generated photoelectrons, thereby resulting in an efficient and high photocatalytic activity.
The Formation of Organogels and Helical Nanofibers from Simple Organic Salts
Authors: Yoshii Yuya , Hoshino Norihisa , Takeda Takashi , Moritomo Hiroki , Kawamata Jun , Nakamura Takayoshi , Akutagawa Tomoyuki
Published: October 2014

Simple organic salts based on aniline‐derived cations and D‐tartrate anions formed organogels and helical nanofibers. The organic salt (p‐fluoroanilinium)(D‐tartrate) was found to generate an organogel despite the absence of a hydrophobic alkyl chain, whereas (p‐iodoanilinium)(D‐tartrate) formed helical nanofibers in braided ropelike structures through a rolling‐up process. The helicity of these nanofibers could be reversed by changing the growth solvent. The driving forces responsible for the formation of the nanofibers were determined to be 1D OH⋅⋅⋅O− hydrogen‐bonding interactions between D‐tartrate anions and π stacking of anilinium cations, as well as steric hindrance between the hydrogen‐bonded chains.
Switchable Enzyme/DNAzyme Cascades by the Reconfiguration of DNA Nanostructures
Authors: Hu Yuwei , Wang Fuan , Lu Chun‐Hua , Girsh Julia , Golub Eyal , Willner Itamar
Published: October 2014

Mimicking cellular transformations and signal transduction pathways by means of biocatalytic cascades proceeding in organized media is a scientific challenge. We describe two DNA machines that enable the “ON/OFF” switchable activation and deactivation of three‐component biocatalytic cascades. One system consists of a reconfigurable DNA tweezers‐type structure, whereas in the second system the catalytic cascade proceeds on a switchable DNA clamp scaffold. The three‐component catalytic cascades consist of β‐galactosidase (β‐Gal), glucose oxidase (GOx), and the K+‐ion‐stabilized hemin‐G‐quadruplex horseradish peroxidase (HRP)‐mimicking DNAzyme. The hemin‐G‐quadruplex‐bridged closed structure of the tweezers or clamp allows the biocatalytic cascades to operate (switched “ON′′), whereas separation of the hemin‐G‐quadruplex by means of 18‐crown‐6‐ether opens the tweezers/clamp structures, thus blocking the catalytic cascade (switched ”OFF“). This study is complemented by two‐component, switchable biocatalytic cascades composed of GOx and hemin‐G‐quadruplex assembled on hairpin‐bridged DNA tweezers or clamp nanostructures.
Copper‐Catalyzed Reductive Cross‐Coupling of Nonactivated Alkyl Tosylates and Mesylates with Alkyl and Aryl Bromides
Authors: Liu Jing‐Hui , Yang Chu‐Ting , Lu Xiao‐Yu , Zhang Zhen‐Qi , Xu Ling , Cui Mian , Lu Xi , Xiao Bin , Fu Yao , Liu Lei
Published: October 2014

A copper‐catalyzed reductive cross‐coupling reaction of nonactivated alkyl tosylates and mesylates with alkyl and aryl bromides was developed. It provides a practical method for efficient and cost‐effective construction of aryl–alkyl and alkyl–alkyl CC bonds with stereocontrol from readily available substrates. When used in an intramolecular fashion, the reaction enables convenient access to various substituted carbo‐ or heterocycles, such as 2,3‐dihydrobenzofuran and benzochromene derivatives.
A phase 1B/2 study of aldoxorubicin in patients with soft tissue sarcoma
Authors: Chawla Sant P. , Chua Victoria S. , Hendifar Andrew F. , Quon Doris V. , Soman Neelesh , Sankhala Kamalesh K. , Wieland D. Scott , Levitt Daniel J.
Published: October 2014

BACKGROUND

Aldoxorubicin, a prodrug of doxorubicin, covalently binds to serum albumin, allowing for the administration of much higher doses of doxorubicin in a previous clinical study. The current phase 1B/2 study evaluated the safety of aldoxorubicin, including preliminary efficacy and safety of its maximum tolerated dose (MTD).

METHODS

Patients aged 18 to 70 years with recurrent/refractory malignant solid tumors received aldoxorubicin at a dose of 230 mg/m2, 350 mg/m2, or 450 mg/m2 (170 mg/m2, 260 mg/m2, or 335 mg/m2 doxorubicin equivalents, respectively) by intravenous infusion once every 21 days for up to 8 consecutive cycles.

RESULTS

A total of 25 patients were enrolled, including 17 patients (68%) with advanced soft tissue sarcoma (STS). The MTD of aldoxorubicin was 350 mg/m2; dose‐limiting toxicities included grade 4 neutropenia and grade 3 febrile neutropenia (NCI CTCAE v4.0). Drug‐related adverse events included myelosuppression, nausea, fatigue, alopecia, stomatitis, vomiting, and oropharyngeal pain. No clinically significant cardiac toxicities were reported. Seven patients (28%) had elevated serum troponin levels while taking part in the study, but these elevations were not clinically significant or associated with cardiac findings. A partial response was achieved in 20% of patients, and stable disease was reported in 40% of patients. The median progression‐free survival was 4.80 months, and the median overall survival was 11.25 months. Among patients with STS who were treated at the MTD (13 patients), a partial response was achieved in 38% and stable disease in 46%; the median progression‐free survival was 11.25 months and the median overall survival was 21.71 months.

CONCLUSIONS

Aldoxorubicin at a dose of 350 mg/m2 administered once every 21 days for up to 8 cycles was found to be acceptably safe and demonstrated preliminary efficacy in patients with advanced solid tumors, including STS. Further investigation of aldoxorubicin is ongoing. Cancer 2015;121:570–579. © 2014 American Cancer Society.
A ciphertext‐policy attribute‐based proxy re‐encryption scheme for data sharing in public clouds
Authors: Liang Kaitai , Fang Liming , Wong Duncan S. , Susilo Willy
Published: October 2014

Ciphertext‐policy attribute‐based proxy re‐encryption (CP‐ABPRE) extends the traditional Proxy Re‐Encryption (PRE) by allowing a semi‐trusted proxy to transform a ciphertext under an access policy to another ciphertext with the same plaintext under a new access policy (i.e., attribute‐based re‐encryption). The proxy, however, learns nothing about the underlying plaintext. CP‐ABPRE has many real world applications, such as fine‐grained access control in cloud storage systems and medical records sharing among different hospitals. All the existing CP‐ABPRE schemes are leaving chosen‐ciphertext attack (CCA) security as an interesting open problem. This paper, for the first time, proposes a new CP‐ABPRE scheme to tackle the problem. The new scheme supports attribute‐based re‐encryption with any monotonic access structures. Despite being constructed in the random oracle model, our scheme can be proven CCA secure under the decisional q‐parallel bilinear Diffie–Hellman exponent assumption. Copyright © 2014 John Wiley & Sons, Ltd.
Effects of Acceptance and Commitment Therapy (ACT) Training on Clinical Psychology Trainee Stress, Therapist Skills and Attributes, and ACT Processes
Authors: Pakenham Kenneth I.
Published: October 2014

Despite the increasing uptake of Acceptance and Commitment Therapy (ACT) by mental health practitioners, few studies have investigated the effects of ACT training on trainees. Clinical psychology trainees (CPTs) are susceptible to high stress such that their training represents a teachable moment for personal application of the therapy skills they learn for clinical practice. This study investigates the effects of ACT training on stress, therapist skills and attributes, and the personal acquisition of ACT strategies in CPTs. Thirty‐two CPTs completed questionnaires before and after university‐based ACT training that consisted of 12 2‐h weekly workshops. Pairwise t‐tests showed that CPTs reported improvements from before to after training on measures of counselling self‐efficacy, client–therapist alliance, self‐kindness, acceptance, defusion, mindfulness and values, and a marginally significant improvement on somatic symptoms, despite a trend towards increased work‐related stress. As predicted, each of the ACT process variables was related to one or more of the therapist stress, skill and attribute variables, such that greater levels of mindfulness, values and acceptance, and less thought suppression were related to better trainee outcomes. This study provides preliminary data on therapist skill development and personal benefits for CPTs related to receiving ACT training that interweaves instruction in competencies acquisition with self‐care. Copyright © 2014 John Wiley & Sons, Ltd.

Key Practitioner Message

This study provides preliminary data on therapist skill development and personal benefits for clinical psychology trainees related to receiving ACT training that integrates training in competencies acquisition with self‐care.

The ACT training offers a framework for integrating the acquisition of clinical competencies and self‐care skills and positive therapist attributes in trainees.

Findings support a strong positive union between the ACT processes and better trainee personal and professional outcomes.
Roll‐to‐Roll Atmospheric Atomic Layer Deposition of Al2O3 Thin Films on PET Substrates
Authors: Ali Kamran , Choi Kyung‐Hyun , Muhammad Nauman Malik
Published: October 2014

A novel technique of roll‐to‐roll atmospheric ALD using a multiple‐slit, gas‐source head is implemented to deposit thin films of Al2O3 on a movable web of a PET substrate at 50 °C under the working pressure of 740 Torr. An appreciable growth rate of 0.98 Å per cycle is observed at a carefully optimized web velocity of 7 mm s−1. Good morphological, chemical, electrical, and optical characteristics are shown by the Al2O3 films produced at a large scale, and they have great potential to be used as insulating and protective films in electronic devices.
Standsicherheit von Kellerwänden bei drückendem Wasser
Authors: Graubner Carl‐Alexander , Förster Valentin , Schmitt Michael
Published: October 2014

Hochwasserkatastrophen treten auch in Deutschland immer häufiger auf. Die dabei entstehenden Beanspruchungen sind im Mauerwerksbau insbesondere für Kellerwände, welche mit einem Bogenmodell bemessen werden, von Bedeutung. Da mit dem normativ vorgeschlagenen Nachweisverfahren kein hydrostatischer Druck berücksichtigt werden kann, wird zunächst eine Nachweismethodik vorgestellt, welche den Lastfall des drückenden Wassers realitätsnah abbildet. Darauf aufbauend werden Bemessungsdiagramme abgeleitet, mit deren Hilfe entweder die maximale Wasserstandhöhe in Abhängigkeit der normativ erforderlichen Mindestauflast bestimmt oder die erforderliche minimale Auflast bei gegebener Wasserstandhöhe abgelesen werden kann. Drückendes Wasser auf Kellerwände im Hochwasserfall stellt eine außergewöhnliche Einwirkung dar. Es kann gezeigt werden, dass die zugehörige Einwirkungskombination bei über die gesamte Wandhöhe hinterfüllten Wänden in vielen Fällen nur bemessungsrelevant wird, wenn das Wasser sehr hoch ansteigt. Bei teilweise hinterfüllten Kellerwänden sind auch bei hydrostatischem Wasserdruck meist kleine Auflasten für eine hinreichende Standsicherheit ausreichend.

Design of basement walls under earth and water pressure. The past decades have shown a tremendous increase in the occurrence of floods in Germany. This development asks for a extension of the design procedure used for basement walls, which is based on an arc model. As the standard regulations do not take into account hydrostatic pressure, the development of a new model regarding water pressure is evident. For this purpose, design diagrams were derived either accounting for the already existing load from the normative method to determine the maximum possible water level or diagrams which show the required minimum dead load for a certain water level. Water pressure due to a flooding represents an extraordinary load with specific partial safety factors within the design situation. If the basement wall is completely backfilled it can be shown, that the extraordinary load of hydrostatic pressure is only relevant for the wall design, if the water level rises near the terrain surface. In case of partially backfilled walls often small dead loads are sufficient to ensure adequate reliability.
Three new species of Onosma L. (Boraginaceae) from Iran
Authors: Mehrabian Ahmad Reza , Sheidai Masoud , Mozaffarian Valeyollah
Published: October 2014

In this paper, we present some important findings in Onosma sect. Onosma. Data were collected during several surveys in western and northwestern Iran. Three new species were discovered and are illustrared here, namely O. sheidaii sp. nov and O. azarbaidjanensis sp. nov (in subsect. Haplotricha) and O. mozaffariani sp. nov. (In subsect. Heterotricha). An extensive review of literature and the comparative study with specimens kept in 14 Asiatic and European herbaria lead to the assessment of their independent, specific status based on both macro and micro‐ morphological characters, which are discussed in respect to possibly closely allied species. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Knockdown of ezrin causes intrahepatic cholestasis by the dysregulation of bile fluidity in the bile duct epithelium in mice
Authors: Hatano Ryo , Akiyama Kaori , Tamura Atsushi , Hosogi Shigekuni , Marunaka Yoshinori , Caplan Michael J. , Ueno Yoshiyuki , Tsukita Sachiko , Asano Shinji
Published: October 2014

Cholangiopathies share common features, including bile duct proliferation, periportal fibrosis, and intrahepatic cholestasis. Damage of biliary epithelium by autoimunne disorder, virus infection, toxic compounds, and developmental abnormalities causes severe progressive hepatic disorders responsible for high mortality. However, the etiologies of these cholestatic diseases remain unclear because useful models to study the pathogenic mechanisms are not available. In the present study, we have found that ezrin knockdown (Vil2kd/kd
) mice develop severe intrahepatic cholestasis characterized by extensive bile duct proliferation, periductular fibrosis, and intrahepatic bile acid accumulation without developmental defects of bile duct morphology and infiltration of inflammatory cells. Ezrin is a membrane cytoskeletal cross‐linker protein, which is known to interact with transporters, scaffold proteins, and actin cytoskeleton at the plasma membrane. We found that the normal apical membrane localizations of several transport proteins including cystic fibrosis transmembrane conductance regulator (CFTR), anion exchanger 2 (AE‐2), aquaporin 1 (AQP1), and Na+/H+ exchanger regulatory factor were disturbed in bile ducts of Vil2kd/kd
mice. Stable expression of a dominant negative form of ezrin in immortalized mouse cholangiocytes also led to the reduction of the surface expression of CFTR, AE‐2, and AQP1. Reduced surface expression of these transport proteins was accompanied by reduced functional expression, as evidenced by the fact these cells exhibited decreased CFTR‐mediated Cl− efflux activity. Furthermore, bile flow and biliary HCO3
− concentration were also significantly reduced in Vil2kd/kd
mice. Conclusion: Dysfunction of ezrin mimics important aspects of the pathological mechanisms responsible for cholangiopathies. The Vil2kd/kd
mouse may be a useful model to exploit in the development and testing of potential therapies for cholangiopathies. (Hepatology 2015;61:1660‐1671)
Differential effects of targeting Notch receptors in a mouse model of liver cancer
Authors: Huntzicker Erik G. , Hötzel Kathy , Choy Lisa , Che Li , Ross Jed , Pau Gregoire , Sharma Neeraj , Siebel Christian W. , Chen Xin , French Dorothy M.
Published: October 2014

Primary liver cancer encompasses both hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA). The Notch signaling pathway, known to be important for the proper development of liver architecture, is also a potential driver of primary liver cancer. However, with four known Notch receptors and several Notch ligands, it is not clear which Notch pathway members play the predominant role in liver cancer. To address this question, we utilized antibodies to specifically target Notch1, Notch2, Notch3, or jagged1 (Jag1) in a mouse model of primary liver cancer driven by v‐akt murine thymoma viral oncogene homolog and neuroblastoma RAS viral oncogene homolog (NRas). We show that inhibition of Notch2 reduces tumor burden by eliminating highly malignant HCC‐ and CCA‐like tumors. Inhibition of the Notch ligand, Jag1, had a similar effect, consistent with Jag1 acting in cooperation with Notch2. This effect was specific to Notch2, because Notch3 inhibition did not decrease tumor burden. Unexpectedly, Notch1 inhibition altered the relative proportion of tumor types, reducing HCC‐like tumors but dramatically increasing CC‐like tumors. Finally, we show that Notch2 and Jag1 are expressed in, and Notch2 signaling is activated in, a subset of human HCC samples. Conclusions: These findings underscore the distinct roles of different Notch receptors in the liver and suggest that inhibition of Notch2 signaling represents a novel therapeutic option in the treatment of liver cancer. (Hepatology 2015;61:942–952)
Polymorphisms of DNA repair genes are related to the pathogenesis of myelodysplastic syndrome
Authors: Ribeiro Howard Lopes , de Oliveira Roberta Taiane Germano , Maia Allan Rodrigo Soares , Pires Ferreira Filho Luiz Ivando , de Sousa Juliana Cordeiro , Heredia Fabiola Fernandes , Magalhães Silvia Maria Meira , Pinheiro Ronald Feitosa
Published: October 2014

Some studies show that alterations in DNA repair genes polymorphisms are associated with the pathogenesis and susceptibility of Myelodysplastic Syndrome (MDS). We genotyped 60 MDS patients for six DNA repair gene polymorphisms: BRCA1 rs4793191, BRCA2 rs9567623, RAD51 rs1801320, XRCC5 rs3835, XRCC6 rs2267437 and LIG4 rs1805388. The G/C heterozygote genotype of rs1801320 polymorphism was associated with a decreased chance of developing MDS (p = 0.05). Additionally, the G/G homozygous genotype was associated with the presence of one cytopenia in whole blood. The genotype C/G and CG + GG of the rs2267437 polymorphism was associated with normal karyotype (p = 0.010) and bone marrow cellularity normocellular + hypercellular (p = 0.023). We found that the A/G heterozygous genotype of the rs3835 polymorphism is associated with decreased chance of developing MDS (p < 0.001). These results support the importance of RAD51, XRCC5 and XRCC6 genes polymorphisms in the maintenance of genomic stability promoting a better understanding of the genesis and etiology of MDS. Copyright © 2014 John Wiley & Sons, Ltd.
Emerging Giants, Aspiring Multinationals, and Foreign Executives: Leapfrogging, Capability Building, and Competing with Developed Country Multinationals
Authors: Arp Frithjof
Published: October 2014

The phenomenon of emerging‐market organizations appointing foreign executives from distant cultural contexts to headquarters positions has stirred public and academic interest. Emerging giants, aspiring multinationals, and even local organizations that focus entirely on domestic markets have joined the global hunt for management talent. This article reports why foreign executives from significant cultural distance are appointed to local headquarters positions, what they contribute, and why these positions are not filled with local executives. Data are sourced from in‐depth interviews with two sample groups in organizations founded and headquartered in Malaysia (46 foreign executives from 13 countries and 25 host‐country peers from three local ethnocultural groups). Triangulation of dyadic data from these two sample groups reveals a dichotomy between the initial reasons for which foreign executives are appointed and the continued reasons why some of these executives remain in their positions. © 2014 Wiley Periodicals, Inc.
A Nanochannel Platform for Single DNA Studies: From Crowding, Protein DNA Interaction, to Sequencing of Genomic Information
Authors: van der Maarel Johan R. C. , Zhang Ce , van Kan Jeroen A.
Published: October 2014

The study of nanochannel‐confined DNA is important from biotechnological and biophysical points of view. We produce nanochannels in elastomer with soft lithography and proton beam writing. Issues concerning DNA confined in such quasi one‐dimensional channels are discussed. We describe DNA stretching via the control of channel diameter and buffer conditions and how the extension can be interpreted with theory and computer simulation. We then discuss the conformation of nano‐confined DNA crowded by neutral polymers and like‐charged proteins. As an example of a protein that has an affinity to DNA, the effect of heat‐stable nucleoid‐structuring protein, H‐NS, on the folding and compaction of DNA is reviewed. Compaction of DNA by eukaryotic protamine and unpacking of pre‐compacted DNA through an increase in salt concentration are discussed. We review results obtained with a novel, cross‐channel device that allows the monitoring of the dynamic, conformational response of DNA after exposure to a ligand or protein and/or a change in buffer conditions in situ. As a biotechnological application, linearization of DNA by bottlebrush coating with a polypeptide copolymer is discussed. It is demonstrated that large‐scale genomic organization can be sequenced using single DNA molecules on an array of elastomeric nanochannels. Overall, our results show that the effects of ligands and proteins on the conformation, folding, and condensation of DNA are not only related to classical controlling factors, such as osmotic pressure, charge, and binding, but that the interplay with confinement in a nanospace is of paramount importance.
Technical improvement using ultra‐slim gastroscopes for direct peroral cholangioscopy: analysis of the initial learning phase
Authors: Weigt Jochen , Kandulski Arne , Malfertheiner Peter
Published: October 2014

Background

Direct peroral cholangioscopy (POCS) is an emerging technique complementing endoscopic retrograde cholangiopancreatography (ERCP). Only few data about the learning process of this technique exist. The objective of this study is to investigate the learning process of POCS in a tertiary center.

Methods

The study was a single center observational trial. All patients were investigated with standard ERCP directly prior to cholangioscopy. The bile ducts were intubated using the balloon anchor technique. The learning process was analyzed using linear regression and cumulative sum analysis.

Results

A total of 42 POCS were performed. Intubation was successful in 38/42 (90%). Reasons for failed intubation were small caliber bile ducts, duodenal diverticulum and papillary adenoma. Failed intubation occurred three times in the first half and only one time in the second half of investigations. The mean intubation time was 8.4 ± 4.9 min (1.6–23 min). The average intubation time changed over time (R2 = −0.7) from 9.5 min in the first half investigations to 7.3 min in the second half procedures. Cumulative sum analysis revealed an initial learning process of nine investigations with significant variations in results followed by a steady improvement in the following investigations.

Conclusions

Direct POCS is a useful tool for the investigation of biliary disease, which demands a short but recognizable initial learning phase even for experienced endoscopists.
Risk factors for technical failure of endoscopic double self‐expandable metallic stent placement by partial stent‐in‐stent method
Authors: Kawakubo Kazumichi , Kawakami Hiroshi , Toyokawa Yoshihide , Otani Koichi , Kuwatani Masaki , Abe Yoko , Kawahata Shuhei , Kubo Kimitoshi , Kubota Yoshimasa , Sakamoto Naoya
Published: October 2014

Background

Endoscopic double self‐expandable metallic stent (SEMS) placement by the partial stent‐in‐stent (PSIS) method has been reported to be useful for the management of unresectable hilar malignant biliary obstruction. However, it is technically challenging, and the optimal SEMS for the procedure remains unknown. The aim of this study was to identify the risk factors for technical failure of endoscopic double SEMS placement for unresectable malignant hilar biliary obstruction (MHBO).

Methods

Between December 2009 and May 2013, 50 consecutive patients with MHBO underwent endoscopic double SEMS placement by the PSIS method. We retrospectively evaluated the rate of successful double SEMS placement and identified the risk factors for technical failure.

Results

The technical success rate for double SEMS placement was 82.0% (95% confidence interval [CI]: 69.2–90.2). On univariate analysis, the rate of technical failure was high in patients with metastatic disease and unilateral placement. Multivariate analysis revealed that metastatic disease was a significant risk factor for technical failure (odds ratio: 9.63, 95% CI: 1.11–105.5). The subgroup analysis after double guidewire insertion showed that the rate of technical success was higher in the laser‐cut type SEMS with a large mesh and thick delivery system than in the braided type SEMS with a small mesh and thick delivery system.

Conclusions

Metastatic disease was a significant risk factor for technical failure of double SEMS placement for unresectable MHBO. The laser‐cut type SEMS with a large mesh and thin delivery system might be preferable for the PSIS procedure.
Quinolinic acid induces disrupts cytoskeletal homeostasis in striatal neurons. Protective role of astrocyte–neuron interaction
Authors: Pierozan Paula , Ferreira Fernanda , de Lima Bárbara Ortiz , Pessoa‐Pureur Regina
Published: October 2014

Quinolinic acid (QUIN) is an endogenous metabolite of the kynurenine pathway involved in several neurological disorders. Among the several mechanisms involved in QUIN‐mediated toxicity, disruption of the cytoskeleton has been demonstrated in striatally injected rats and in striatal slices. The present work searched for the actions of QUIN in primary striatal neurons. Neurons exposed to 10 µM QUIN presented hyperphosphorylated neurofilament (NF) subunits (NFL, NFM, and NFH). Hyperphosphorylation was abrogated in the presence of protein kinase A and protein kinase C inhibitors H89 (20 μM) and staurosporine (10 nM), respectively, as well as by specific antagonists to N‐methyl‐D‐aspartate (50 µM DL‐AP5) and metabotropic glutamate receptor 1 (100 µM MPEP). Also, intra‐ and extracellular Ca2+ chelators (10 µM BAPTA‐AM and 1 mM EGTA, respectively) and Ca2+ influx through L‐type voltage‐dependent Ca2+ channel (10 µM verapamil) are implicated in QUIN‐mediated effects. Cells immunostained for the neuronal markers βIII‐tubulin and microtubule‐associated protein 2 showed altered neurite/neuron ratios and neurite outgrowth. NF hyperphosphorylation and morphological alterations were totally prevented by conditioned medium from QUIN‐treated astrocytes. Cocultured astrocytes and neurons interacted with one another reciprocally, protecting them against QUIN injury. Cocultured cells preserved their cytoskeletal organization and cell morphology together with unaltered activity of the phosphorylating system associated with the cytoskeleton. This article describes cytoskeletal disruption as one of the most relevant actions of QUIN toxicity in striatal neurons in culture with soluble factors secreted by astrocytes, with neuron–astrocyte interaction playing a role in neuroprotection. © 2014 Wiley Periodicals, Inc.
Cronbach's alpha reliability: Interval estimation, hypothesis testing, and sample size planning
Authors: Bonett Douglas G. , Wright Thomas A.
Published: October 2014

Cronbach's alpha is one of the most widely used measures of reliability in the social and organizational sciences. Current practice is to report the sample value of Cronbach's alpha reliability, but a confidence interval for the population reliability value also should be reported. The traditional confidence interval for the population value of Cronbach's alpha makes an unnecessarily restrictive assumption that the multiple measurements have equal variances and equal covariances. We propose a confidence interval that does not require equal variances or equal covariances. The results of a simulation study demonstrated that the proposed method performed better than alternative methods. We also present some sample size formulas that approximate the sample size requirements for desired power or desired confidence interval precision. R functions are provided that can be used to implement the proposed confidence interval and sample size methods. Copyright © 2014 John Wiley & Sons, Ltd.
Impact of biochars on swell–shrinkage behavior, mechanical strength, and surface cracking of clayey soil
Authors: Zong Yutong , Chen Danping , Lu Shenggao
Published: October 2014

Swell–shrinkage, cracking and stickiness of expansive clayey soils usually lead to their low yield. Improvement of these poor soil physical properties is a key goal for enhancing the crop productivity of expansive clayey soils. This article presents results of a study on the impact of three biochars produced from wheat straw (SB), woodchips (WCB), and wastewater sludge (WSB) on the swell–shrinkage behavior, mechanical strength, and surface cracking of a clayey soil. The soil was treated with biochars at the rate of 0, 20, 40, and 60 g biochar kg−1 soil, respectively; and incubated for 180 d in glasshouse. Application of biochars decreased significantly (p < 0.01) the coefficient of linear extensibility (COLE) of the soil, the effect of SB being most prominent. The tensile strength (TS) of the clayey soil was originally 937 kPa, which decreased to 458 kPa, 495 kPa and 659 kPa for 6% SB‐, WCB‐, and WSB‐amended soils, respectively. Shear strength tests indicated that biochars significantly reduced cohesion (c) and increased internal friction angle (θ). Biochar significantly reduced the formation of soil surface cracks, surface area, and length of the cracks. The surface area density of cracks in the 6% biochar‐amended soils decreased by 14% for SB, 17% for WCB, and 19% for WSB, respectively, compared with control. The results suggest that biochar can be used as a soil amendment for improving the poor physical properties of the clayey soil, particularly in terms of reduction in swell–shrinkage, tensile strength and surface area density of cracking.
The combination of localized phosphorus and water supply indicates a high potential for savings of irrigation water and phosphorus fertilizer
Authors: Zhan Ai , Chen Xinping , Li Shiqing
Published: October 2014

Water and phosphorus (P) are often unevenly distributed in the soil profile, thus limiting water and P uptake and plant growth. A soil column and a split‐root experiment were conducted to quantify the effect of localized water and P supply on shoot growth, root morphology, specific P uptake (SPU), P‐use efficiency (PUE), and water‐use efficiency (WUE) of maize (Zea mays L.). Our results indicate that roots preferentially grow in the layer or compartment with both adequate water and P supply, subsequently stimulating SPU, PUE, and WUE, and enhancing shoot growth. Compared with the treatments in which both layers and compartments were supplied with adequate P and/or water, the growth of maize was maintained or minimally affected. SPU, PUE, and WUE were increased when both P and water were supplied in one layer or one compartment only. These findings show that normal plant growth with an adequate P uptake was achieved even if part of the roots were supplied with 2/3 (soil column experiment) and 1/2 (split‐root experiment) of the phosphorus and water supplied in the full‐phosphorus and full‐water treatment. Changes in root morphology under water stress conditions induced by the application of phosphorus and water in deeper soil layers or to a part of the roots may have substantial practical implications for agricultural production and environmental protection.
Lymph node status after resection for gallbladder adenocarcinoma: Prognostic implications of different nodal staging/scoring systems
Authors: Amini Neda , Spolverato Gaya , Kim Yuhree , Gupta Rohan , Margonis Georgios Antonios , Ejaz Aslam , Pawlik Timothy M.
Published: October 2014

Background and Objectives

Several lymph node (LN) staging/scoring systems have been proposed to stratify the prognosis of patients with gallbladder adenocarcinoma (GBA). We sought to define the prognostic performance of the most commonly utilized LN staging/scoring systems including AJCC/UICC N stage, lymph node ratio (LNR), log odds (LODDS), and N score, among patients with GBA.

Method

Between 2004 and 2010, 1,124 patients with GBA were identified from the Surveillance Epidemiology and End Results (SEER) database. The discriminative ability of each LN staging/scoring system was assessed using the Akaike's Information Criterion (AIC) and the Harrell's concordance index.

Results

When assessed using categorical values, LNR had a modest, improved ability to discriminate patients with regard to prognosis (C‐index: 0.615; AIC: 2118.2) compared with AJCC/UICC N stage or N score and a prognostic discrimination comparable to LODDS. Among patients who had a total number of LN examined (TNLE) of 1 or 2, all the staging/scoring systems performed comparably. In contrast, among patients who had ≥4 TNLE, LODDS performed the best (C‐index: 0.613; AIC: 303.2).

Conclusion

The performance of the different LN staging/scoring systems varied based on the TNLE. In particular, for patients who had ≥4 TNLE, LODDS out‐performed the other staging/scoring systems. J. Surg. Oncol. 2015 111:299–305. © 2014 Wiley Periodicals, Inc.
Mitochondrial dysfunction in steatotic rat livers occurs because a defect in complex i makes the liver susceptible to prolonged cold ischemia
Authors: Chu Michael J. J. , Hickey Anthony J. R. , Jiang Yannan , Petzer Amorita , Bartlett Adam S. J. R. , Phillips Anthony R. J.
Published: October 2014

Steatotic livers are susceptible to cold ischemia, which is thought to be secondary to mitochondrial dysfunction. Ischemic preconditioning (IPC) has been reported to improve liver function in the setting of warm ischemia/reperfusion injury, but the effect of IPC on steatotic liver mitochondrial function (MF) with cold ischemia has not been previously evaluated. We aimed to evaluate MF with various severities of hepatic steatosis after various durations of cold ischemia storage with or without IPC. Male Sprague‐Dawley rats were fed a normal diet or a high‐fat/high‐sucrose diet for 1, 2, or 4 weeks to induce mild (<30%), moderate (30%‐60%), or severe (>60%) macrovesicular steatosis, respectively. Liver MF was tested with high‐resolution respirometry after 1.5, 4, 8, 12, 18, and 24 hours of cold ischemia. Rats in each group (n = 10) underwent 10 minutes of IPC or no IPC before cold ischemia. The baseline (time 0) respiration was similar for lean and severely steatotic livers despite decreased mitochondrial complex I (C‐I) activity in severely steatotic livers. Hepatic steatosis was associated with increased C‐I–mediated leaks and decreased respiratory control ratios (RCRs) after cold ischemia. Mildly, moderately, and severely steatotic livers showed significantly lower RCRs after 8, 1.5, and 1.5 hours of cold ischemia, respectively, in comparison with lean livers. IPC restored RCRs in mildly steatotic livers to levels comparable to those in lean livers for up to 24 hours of cold ischemia via the attenuation of C‐I–mediated leaks, but it had no beneficial effect on moderately and severely steatotic livers. In conclusion, steatotic livers exhibited apparent mitochondrial dysfunction through an alteration in C‐I activity, and this made them more susceptible to prolonged cold ischemia. The clinically based IPC protocol used here restored MF in cases of mild hepatic steatosis by attenuating C‐I–mediated leaks after prolonged cold ischemia, but it did work not in livers with moderate or severe steatosis. Liver Transpl 21:396–407, 2015. © 2015 AASLD.
SB‐S Core‐Shell Particles in Semicontinuous Seeded Emulsion Polymerization and their use as Impact Modifier
Authors: Uliana Nilva R. , Machado Ricardo A. F. , Sayer Claudia , Araújo Pedro H.H.
Published: October 2014

The impact resistance of polymeric materials can be modified by the addition of polymer particles with core shell structure, in which the core consists of a rubber phase and the shell of a glassy phase. In this work, the synthesis of core‐shell particles (polybutadiene‐rich phase / polystyrene rich phase) by emulsion polymerization and their use as impact modifiers in crystal polystyrene, PS, was investigated. Reactions were followed by gravimetry and dynamic light scattering analysis and core‐shell morphology was determined by transmission electron microscopy. This latex, after dried, was incorporated into a PS matrix in a single screw extruder. The impact resistance increased with the incorporation of the core‐shell particles and with the number of passes through the extruder.
Synthesis and Characterization of Diolefin/Propylene Copolymers by Ziegler‐Natta Polymerization
Authors: Lima Aline , Azeredo Ana Paula , Nele Marcio , Liberman Susana , Pinto José Carlos
Published: October 2014

Diolefins can be used as comonomers in propylene copolymerizations in order to modify some of the final properties of the obtained poly(propylene) (PP) resins. Although reduction of catalyst activity can be expected when such copolymerizations are performed with standard heterogeneous Ziegler‐ Natta catalysts, copolymers containing 1,5‐hexadiene (HD) and 1,7‐octadiene (OD) can be produced at high rates when the comonomer content is sufficiently low (below 2 mol%); however, the presence of very small amounts of 5‐ethylidene‐2‐norbornene (ENB) leads to complete catalyst inhibition. It is shown that incorporation of dienes lead to decrease of the melting point of the final product, especially in presence of ENB. When compared to HD, addition of OD causes more pronounced modification of the melt flow index and weight‐average molecular weight, although the xylene solubles is less sensitive to the comonomer feed when the comonomer composition is low. Obtained results indicate that small amounts of dienes can be used at plant site to modify the final properties of PP resins produced with standard heterogeneous Ziegler‐Natta polymerizations.
Temperature‐dependent MR signals in cortical bone: Potential for monitoring temperature changes during high‐intensity focused ultrasound treatment in bone
Authors: Ramsay Elizabeth , Mougenot Charles , Kazem Mohammad , Laetsch Theodore W. , Chopra Rajiv
Published: October 2014

Purpose

Because existing magnetic resonance thermometry techniques do not provide temperature information within bone, high‐intensity focused ultrasound (HIFU) exposures in bone are monitored using temperature changes in adjacent soft tissues. In this study, the potential to monitor temperature changes in cortical bone using a short TE gradient echo sequence is evaluated.

Methods

The feasibility of this proposed method was initially evaluated by measuring the temperature dependence of the gradient echo signal during cooling of cortical bone samples implanted with fiber‐optic temperature sensors. A subsequent experiment involved heating a cortical bone sample using a clinical MR‐HIFU system.

Results

A consistent relationship between temperature change and the change in magnitude signal was observed within and between cortical bone samples. For the two‐dimensional gradient echo sequence implemented in this study, a least‐squares linear fit determined the percentage change in signal to be (0.90 ± 0.01)%/°C. This relationship was used to estimate temperature changes observed in the HIFU experiment and these temperatures agreed well with those measured from an implanted fiber‐optic sensor.

Conclusion

This method appears capable of displaying changes related to temperature in cortical bone and could improve the safety of MR‐HIFU treatments. Further investigations into the sensitivity of the technique in vivo are warranted. Magn Reson Med 74:1095–1102, 2015. © 2014 Wiley Periodicals, Inc.
Models to predict the operating temperature of different photovoltaic modules in outdoor conditions
Authors: Mora Segado Patricia , Carretero Jesús , Sidrach‐de‐Cardona Mariano
Published: October 2014

The operating temperature of photovoltaic modules under real operating conditions is important information when designing and sizing those systems. This paper proposes new models to predict this temperature for different technology modules under the climate conditions of southern Spain using meteorological parameters. The proposed models are hourly and instantaneous. Those models are compared with previous models existing in the literature. The results obtained show that because of the thermal inertia of the modules, only the proposed hourly models allow the average temperature of the modules to be determined accurately. The temperature of the modules can be predicted using the two‐parameter hourly model proposed in this paper with a mean absolute percentage error less than 6.0% for the technologies tested. Copyright © 2014 John Wiley & Sons, Ltd.
Correlates of Stress and Coping among Jordanian Nursing Students during Clinical Practice in Psychiatric/Mental Health Course
Authors: Alzayyat Abdulkarim , Al‐Gamal Ekhlas
Published: October 2014

Training in psychiatric settings is stressful for nursing students. The purpose of this study was to examine the correlations between the students' characteristics, their stress degrees, stressors and types of coping strategies they experience during training in psychiatric course. A descriptive, correlational, longitudinal design was used. Sixty‐five undergraduate nursing students were recruited randomly from five Jordanian universities. Self‐report questionnaires were administered at the second semester of the 2012–2013 academic year. The findings showed that students who utilized avoidance or transference strategies reported high stress degrees. Moreover, the results showed that those students who were in the fourth year, with a low family income, who avoid extracurricular activities, with a low academic grade or who registered in other clinical course(s) reported high stress degrees. These findings present a worthy data for the clinical instructors that facilitate students training in psychiatric settings and promote their psychosocial well‐being. Copyright © 2014 John Wiley & Sons, Ltd.
Stressors and Coping Strategies of UK Firefighters during On‐duty Incidents
Authors: Young Paul M. , Partington Sarah , Wetherell Mark A. , St Clair Gibson Alan , Partington Elizabeth
Published: October 2014

Operational response by firefighters requires an abrupt change from rest to near‐maximal physical effort and incorporates almost instant stress management that must be made during extreme heat, limited time and partial information, yet little is known about the coping strategies incorporated to manage the physiological and psychological demands associated with this environment. A sample of 22 UK firefighters took part in focus groups identifying frequently used coping techniques based upon problem‐focused and emotion‐focused coping methods. Findings suggest problem‐orientated coping comprised half of the total coping strategies quoted by participants, with a third of responses being categorized as emotion‐focused methods, and 17% were considered to be both problem‐focused and emotion‐focused techniques. Responses indicate problem‐focused methods are often utilized en route to the incident, and at the early stages of operational tasks. Emotion‐focused responses are more common during periods of fatigue and exhaustion and post‐incident, and problem‐focused and emotion‐focused techniques were found post‐incident, although there was often an overlap between methods and they perhaps should not be treated as three distinct stages. The importance of peer support and potential benefits to firefighter well‐being and operational performance are discussed. Copyright © 2014 John Wiley & Sons, Ltd.