bluuebunny/crossref_metadata_2025_split huggingface dataset:
Atomistic Investigation of Load Transfer Between DWNT Bundles “Crosslinked” by PMMA Oligomers
Authors: Naraghi Mohammad , Bratzel Graham H. , Filleter Tobin , An Zhi , Wei Xiaoding , Nguyen SonBinh T. , Buehler Markus J. , Espinosa Horacio D. 
Published: November 2012

AbstractThe production of carbon nanotube (CNT) yarns possessing high strength and toughness remains a major challenge due to the intrinsically weak interactions between “bare” CNTs. To this end, nanomechanical shear experiments between functionalized bundles of CNTs are combined with multiscale simulations to reveal the mechanistic and quantitative role of nanotube surface functionalization on CNT‐CNT interactions. Notably, the in situ chemical vapor deposition (CVD) functionalization of CNT bundles by poly(methyl methacrylate) (PMMA)‐like oligomers is found to enhance the shear strength of bundle junctions by about an order of magnitude compared with “bare” van der Waals interactions between pristine CNTs. Through multiscale simulations, the enhancement of the shear strength can be attributed to an interlocking mechanism of polymer chains in the bundles, dominated by van der Waals interactions, and stretching and alignment of chains during shearing. Unlike covalent bonds, such synergistic weak interactions can re‐form upon failure, resulting in strong, yet robust fibers. This work establishes the significance of engineered weak interactions with appropriate structural distribution to design CNT yarns with high strength and toughness, similar to the design paradigm found in many biological materials.
Polyhedral Oligosilsesquioxane‐Modified Boron Nitride Nanotube Based Epoxy Nanocomposites: An Ideal Dielectric Material with High Thermal Conductivity
Authors: Huang Xingyi , Zhi Chunyi , Jiang Pingkai , Golberg Dmitri , Bando Yoshio , Tanaka Toshikatsu 
Published: November 2012

AbstractDielectric polymer composites with high thermal conductivity are very promising for microelectronic packaging and thermal management application in new energy systems such as solar cells and light emitting diodes (LEDs). However, a well‐known paradox is that conventional composites with high thermal conductivity usually suffer from the high dielectric constant and high dielectric loss, while on the other hand, composite materials with excellent dielectric properties usually possess low thermal conductivity. In this work, an ideal dielectric thermally conductive epoxy nanocomposite is successfully fabricated using polyhedral oligosilsesquioxane (POSS) functionalized boron nitride nanotubes (BNNTs) as fillers. The nanocomposites with 30 wt% fraction of POSS modified BNNTs exhibit much lower dielectric constant, dielectric loss tangent, and coefficient of thermal expansion in comparison with the pure epoxy resin. As an example, below 100 Hz, the dielectric loss of the nanocomposites with 20 and 30 wt% BNNTs is reduced by one order of magnitude in comparison with the pure epoxy resin. Moreover, the nanocomposites show a dramatic thermal conductivity enhancement of 1360% in comparison with the pristine epoxy resin at a BNNT loading fraction of 30 wt%. The merits of the designed composites are suggested to originate from the excellent intrinsic properties of embedded BNNTs, effective surface modification by POSS molecules, and carefully developed composite preparation methods.
Word smithing in medical genetics. Part II
Authors: Cohen Jr. M. Michael 
Published: November 2012

AbstractTerminology discussed here is subsumed under “common misused terms in medical genetics articles” (depressed nasal bridge; anophthalmia; rotated ears; low‐set ears; heterotopia; ASD as an abbreviation for autism spectrum disorders; mental retardation; “radiographs revealed something”; and new syndrome) and also subsumed under “erroneous terminology that persists at the editorial and publishing level” (failure to understand the possessive case of names ending in “s”; failure to understand that a comma should not be used before Jr; problematic use of numbers in reference sections; failure to italicize Latin phrases; failure to honor book titles that begin words with upper case letters; omitting the corresponding author; and inadequate citation of foreign languages). © 2012 Wiley Periodicals, Inc.
Synthese aromatischer Nitrile mithilfe nichtmetallischer CN‐Quellen
Authors: Kim Jinho , Kim Hyun Jin , Chang Sukbok 
Published: November 2012

AbstractAromatische Nitrile werden effizient durch die übergangsmetallkatalysierte Cyanierung von Aryl(pseudo)halogeniden mit metallischen CN‐Quellen wie CuCN, KCN, NaCN, Zn(CN)2, TMSCN oder K4[Fe(CN)6] synthetisiert. Nachteilig an diesen Verfahren sind jedoch die stöchiometrischen Mengen von Metallabfall, die Vergiftung des Metallkatalysators oder die Bildung von toxischem HCN‐Gas. Für die Cyanierung von Aryl‐Halogen‐ und Aryl‐H‐Bindungen wird daher seit einiger Zeit auch eine Reihe von “nichtmetallischen” organischen CN‐Quellen erkundet. Dieser Kurzaufsatz stellt verschiedene nichtmetallische CN‐Quellen und ihre Anwendung für die Synthese von Arylnitrilen vor.
Biocomposites based on lignin and plasticized poly(L‐lactic acid)
Authors: Rahman Mohammed Arifur , De Santis Diego , Spagnoli Gloria , Ramorino Giorgio , Penco Maurizio , Phuong Vu Thanh , Lazzeri Andrea 
Published: November 2012

AbstractIn this research work, biocomposites based on a ternary system containing softwood Kraft lignin (Indulin AT), poly‐L‐lactic acid (PLLA) and polyethylene glycol (PEG) have been developed. Two binary systems based on PLLA/PEG and PLLA/lignin have also been studied to understand the role of plasticizer (i.e., PEG) and filler (i.e., lignin) on the overall physicomechanical behavior of PLLA. All samples have been prepared by melt‐blending. A novel approach has also been introduced to improve the compatibility between PLLA and PEG by using a transesterification catalyst under reactive‐mixing conditions. In PEG plasticized PLLA flexibility increases with increasing content of PEG and no significant effect of the molecular weight of PEG on the flexibility of PLLA has been observed. Differential scanning calorimetry and size‐exclusion chromatography along with FTIR analysis show the formation of PLLA‐b‐PEG copolymer for high temperature processed PLLA/PEG systems. On the other hand, binary systems containing lignin show higher stiffness than PLLA/PEG system and good adhesion between the particles and the matrix has been observed by scanning electron microscopy. However, a concomitant good balance in stiffness introduced by the lignin particles and flexibility introduced by PEG has been observed in the ternary systems. This study also showed that high temperature reactive melt‐blending of PLLA/PEG leads to the formation of a segmented PLLA‐b‐PEG block copolymer. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Effect of core‐shell morphology evolution on the rheology, crystallization, and mechanical properties of PA6/EPDM‐g‐MA/HDPE ternary blend
Authors: Dou Rui , Wang Wei , Zhou Yan , Li Lan‐peng , Gong Lei , Yin Bo , Yang Ming‐bo 
Published: November 2012

AbstractIn this article, polyamide 6 (PA6), maleic anhydride grafted ethylene‐propylene‐diene monomer (EPDM‐g‐MA), high‐density polyethylene (HDPE) were simultaneously added into an internal mixer to melt‐mixing for different periods. The relationship between morphology and rheological behaviors, crystallization, mechanical properties of PA6/EPDM‐g‐MA/HDPE blends were studied. The phase morphology observation revealed that PA6/EPDM‐g‐MA/HDPE (70/15/15 wt %) blend is constituted from PA6 matrix in which is dispersed core‐shell droplets of HDPE core encapsulated by EPDM‐g‐MA phase and indicated that the mixing time played a crucial role on the evolution of the core‐shell morphology. Rheological measurement manifested that the complex viscosity and storage modulus of ternary blends were notable higher than the pure polymer blends and binary blends which ascribed different phase morphology. Moreover, the maximum notched impact strength of PA6/EPDM‐g‐MA/HDPE blend was 80.7 KJ/m2 and this value was 10–11 times higher than that of pure PA6. Particularly, differential scanning calorimetry results indicated that the bulk crystallization temperature of HDPE (114.6°C) was partly weakened and a new crystallization peak appeared at a lower temperature of around 102.2°C as a result of co‐crystal of HDPE and EPDM‐g‐MA. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Comparative study of anal acoustic reflectometry and anal manometry in the assessment of faecal incontinence
Authors: Hornung B R , Mitchell P J , Carlson G L , Klarskov N , Lose G , Kiff E S 
Published: November 2012

Abstract

Background
Anal acoustic reflectometry (AAR) is a reproducible technique providing a novel physiological assessment of anal sphincter function. It may have advantages over conventional anal manometry. The aims of this study were to determine the ability of AAR and anal manometry to identify changes in anal sphincter function in patients with faecal incontinence (FI) and to relate these changes to the severity of FI.

Methods
Women with FI underwent assessment with AAR and anal manometry. All patients completed the Vaizey FI questionnaire and were classified according to symptom type (urge, passive or mixed) and integrity of the anal sphincters. The ability of AAR and anal manometry to correlate with symptom severity was evaluated. AAR was compared with anal manometry in detecting differences in anal sphincter function between symptomatic subgroups, and patients with and without a sphincter defect.

Results
One hundred women with FI were included in the study. The AAR variables opening pressure, opening elastance, closing elastance and squeeze opening pressure correlated with symptom severity, whereas the manometric measurements maximum resting pressure and maximum squeeze pressure did not. Unlike anal manometry, AAR was able to detect differences in anal sphincter function between different symptomatic subgroups, whereas anal manometry was not. An anal sphincter defect was not associated with a significant change in anal sphincter function determined by either AAR or anal manometry.

Conclusion
In the assessment of women with FI, AAR variables correlated with symptom severity and could distinguish between different symptomatic subgroups. AAR may help to guide management in these patients.
Long-term follow-up of the Medical Research Council CLASICC trial of conventional versus laparoscopically assisted resection in colorectal cancer
Authors: Green B L , Marshall H C , Collinson F , Quirke P , Guillou P , Jayne D G , Brown J M 
Published: November 2012

Abstract

Background
Laparoscopic resection is used widely in the management of colorectal cancer; however, the data on long-term outcomes, particularly those related to rectal cancer, are limited. The results of long-term follow-up of the UK Medical Research Council trial of laparoscopically assisted versus open surgery for colorectal cancer are presented.

Methods
A total of 794 patients from 27 UK centres were randomized to laparoscopic or open surgery in a 2:1 ratio between 1996 and 2002. Long-term follow-up data were analysed to determine differences in survival outcomes and recurrences for intention-to-treat and actual treatment groups.

Results
Median follow-up of all patients was 62·9 (interquartile range 22·9 − 92·8) months. There were no statistically significant differences between open and laparoscopic groups in overall survival (78·3 (95 per cent confidence interval (c.i.) 65·8 to 106·6) versus 82·7 (69·1 to 94·8) months respectively; P = 0·780) and disease-free survival (DFS) (89·5 (67·1 to 121·7) versus 77·0 (63·3 to 94·0) months; P = 0·589). In colonic cancer intraoperative conversions to open surgery were associated with worse overall survival (hazard ratio (HR) 2·28, 95 per cent c.i. 1·47 to 3·53; P &lt; 0·001) and DFS (HR 2·20, 1·31 to 3·67; P = 0·007). In terms of recurrence, no significant differences were observed by randomized procedure. However, at 10 years, right colonic cancers showed an increased propensity for local recurrence compared with left colonic cancers: 14·7 versus 5·2 per cent (difference 9·5 (95 per cent c.i. 2·3 to 16·6) per cent; P = 0·019).

Conclusion
Long-term results continue to support the use of laparoscopic surgery for both colonic and rectal cancer.
Severity of portal hypertension and prediction of postoperative liver failure after liver resection in patients with Child–Pugh grade A cirrhosis
Authors: Chen X , Zhai J , Cai X , Zhang Y , Wei L , Shi L , Wu D , Shen F , Lau W-Y , Wu M 
Published: November 2012

Abstract

Background
Patients with Child–Pugh grade A cirrhosis and clinical evidence of portal hypertension are likely to develop posthepatectomy liver failure (PHLF). Whether such patients are suitable candidates for partial hepatectomy is controversial. This study explored the impact of portal venous pressure (PVP) on PHLF and the possibility of stratifying patients with Child–Pugh grade A cirrhosis for risk of PHLF using clinical data alone.

Methods
Between April 2009 and May 2011, consecutive patients who underwent partial hepatectomy for hepatocellular carcinoma and intraoperative measurement of PVP were included in this prospective study. Using signs of clinically significant portal hypertension (CSPH), patients with Child–Pugh grade A cirrhosis were subclassified into three groups: no, mild and severe CSPH. Risk factors for PHLF were subjected to univariable and multivariable analysis, and receiver operating characteristic (ROC) curve analysis.

Results
Sixty-seven (35·3 per cent) of 190 patients developed PHLF, which was persistent in 12 patients (6·3 per cent). Four patients (2·1 per cent) died from PHLF within 3 months of surgery. Multivariable analysis showed both PVP and CSPH to be independent predictors of PHLF (P &lt; 0·001). PVP values, incidence of PHLF and persistent PHLF were significantly higher in the severe CSPH group than in the other two groups (P &lt; 0·001). Severe CSPH (odds ratio 27·68, P = 0·005) and a preoperative neutrophil : lymphocyte ratio (NLR) of 2·8 or above (odds ratio 49·75, P = 0·002) were independent factors affecting the incidence of persistent PHLF.

Conclusion
The severity of CSPH, corresponding to different PVP levels, could be used to stratify patients with Child-Pugh grade A cirrhosis and to predict the incidence of PHLF. Patients with severe CSPH or a NLR of 2·8 or above were more likely to develop persistent PHLF after partial hepatectomy.
Effects of hydrogen sulphide in an experimental model of renal ischaemia–reperfusion injury
Authors: Hunter J P , Hosgood S A , Patel M , Rose R , Read K , Nicholson M L 
Published: November 2012

Abstract

Background
Renal ischaemia–reperfusion injury (IRI) is a major cause of acute renal failure and renal transplant dysfunction. The aim of this study was to investigate the efficacy of the endogenous gaseous signalling molecule hydrogen sulphide in protecting against renal IRI.

Methods
Large White female pigs underwent laparotomy and cross-clamping of the left renal pedicle for 60 min. Animals were allocated randomly to treatment with either intravenous hydrogen sulphide (n = 6) or saline control (n = 6) 10 min before clamp release, and then underwent a right nephrectomy. Staff were blinded to treatment allocation and animals were recovered for 7 days.

Results
Hydrogen sulphide therapy resulted in a marked reduction in kidney injury with reduced serum creatinine levels on days 1–5, in a reduced area under the creatinine–time curve, and a halving of the time to achieve a creatinine level of less than 250 µmol/l, compared with the control. Hydrogen sulphide also preserved glomerular function, as shown by the urinary protein/creatinine ratio, which, compared with baseline, increased on days 1 and 3 in the control group (mean(s.e.m.) 3·22(1·43), P = 0·016 and 2·59(1·27), P = 0·031), but not in the treatment group (0·99(0·23), P = 0·190 and 1·06(0·44), P = 0·110, respectively). Mean(s.e.m.) tumour necrosis factor α levels at 6 h postreperfusion increased in the control animals (56(6) versus 115(21) pg/ml; P = 0·026), but not in the hydrogen sulphide-treated animals (61(7) versus 74(11) pg/ml; P = 0·460). Renal neutrophil infiltration at 30 min (myeloperoxidase staining) was also significantly reduced by treatment with hydrogen sulphide (P = 0·016).

Conclusion
Hydrogen sulphide offers a promising new approach to ameliorating renal IRI with potential translation into a number of clinical settings, including renal transplantation.
Liver resection for hepatocellular carcinoma in patients without cirrhosis
Authors: Thelen A , Benckert C , Tautenhahn H-M , Hau H-M , Bartels M , Linnemann J , Bertolini J , Moche M , Wittekind C , Jonas S 
Published: November 2012

Abstract

Background
Data on liver resection for hepatocellular carcinoma (HCC) without cirrhosis are sparse. The present study was conducted to evaluate the indications and results of liver resection for HCC with regard to safety and efficacy.

Methods
Data for patients who had liver resection for HCC without cirrhosis between January 1996 and March 2011 were retrieved retrospectively using a prospective database containing information on all patients who underwent hepatectomy for HCC. Patient and tumour characteristics were analysed for influence on overall and disease-free survival to identify prognostic factors by univariable and multivariable analysis.

Results
The 1-, 3- and 5-year overall survival rates after resection with curative intent for HCC without cirrhosis were 84, 66 and 50 per cent respectively. Disease-free survival rates were 69, 53 and 42 per cent respectively. The 90-day mortality rate was 4·5 per cent (5 of 110 patients). Surgical radicality and growth pattern of the tumour were independent prognostic factors for overall survival. Disease-free survival after resection with curative intent was independently affected by growth pattern and by the number and size of tumour nodules.

Conclusion
Liver resection for HCC without cirrhosis carries a low perioperative risk and excellent long-term outcome if radical resection is achieved.
Non-operative management of acute cholecystitis in the elderly (Br J Surg 2012; 99: 1254–1261)
Authors: Bass G , Walsh T N 
Published: November 2012

Abstract
The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses should be sent electronically via the BJS website (www.bjs.co.uk). All letters will be reviewed and, if approved, appear on the website. A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length.
Deactivation and Regeneration of H‐USY Zeolite during Lignin Catalytic Fast Pyrolysis
Authors: Ma Zhiqiang , van Bokhoven Jeroen A. 
Published: November 2012

AbstractCatalytic fast pyrolysis of alkaline lignin over H‐USY zeolites uniquely yields a high fraction of aromatics but only very small amounts of tar and char. This study focused on the deactivation and regeneration of the H‐USY zeolite. N2 physisorption, thermogravimetric analysis (TGA), temperature‐programmed desorption of NH3, and 27Al MAS NMR analysis were used to determine coking, pore topology, and the number of acid sites of the deactivated and regenerated H‐USY catalyst. Deactivation occurred mainly owing to coke deposition on the catalyst. Both pore blockage and active site poisoning were observed during deactivation. The coke was removed through calcination of the deactivated catalysts in air at high temperature. Calcination restored the high porosity and the acid sites to a large extent. Even better catalytic performance was obtained after the reintroduction of protons through an ion‐exchange step. Recovery of catalytic properties was high but incomplete, because of structural changes in the catalyst during the reaction–regeneration process.
Synthesis of Dimethyl Carbonate from Methyl Carbamate and Methanol Using a Fixed‐Bed Reactor
Authors: Wang D. , Zhang X. , Wei W. , Sun Y. 
Published: November 2012

AbstractSeveral mixed oxide catalysts were prepared by coprecipitation for dimethyl carbonate (DMC) synthesis from methyl carbamate and methanol. During the batch process, the DMC yield was below 35 %. In order to minimize the unfavorable thermodynamic equilibrium and side reactions for the DMC synthesis, a fixed‐bed reactor was designed. A maximum DMC yield of ∼ 73 % could be realized over a ZnO‐Al2O3 catalyst. The effects of reaction conditions for this type of reactor were investigated in detail.
Measurement and Simulation of Axial Velocity in a Filter Bag
Authors: Saleem M. , Tahir M. S. , Krammer G. 
Published: November 2012

AbstractThe axial velocity in two different tests with pulse‐jet bag filters made of needle felts on a pilot‐scale test facility separating limestone dust from air under ambient conditions is measured and simulated at different cake area loads. Results reveal that the axial velocity profiles are not truly linear along the whole length of the bag. A nonuniform gas flow prevails when the bags are differently dust‐loaded. The same behaviors are observed even at the end of filtration cycles at different upper pressure drop limits. At the higher upper limit, the nonuniformity is stronger. Radial velocity profiles are nearly symmetric along the length of the bag.
Mechanistic Origin of the Vibrational Coherence Accompanying the Photoreaction of Biomimetic Molecular Switches
Authors: Léonard Jérémie , Schapiro Igor , Briand Julien , Fusi Stefania , Paccani Riccardo Rossi , Olivucci Massimo , Haacke Stefan 
Published: November 2012

AbstractThe coherent photoisomerization of a chromophore in condensed phase is a rare process in which light energy is funneled into specific molecular vibrations during electronic relaxation from the excited to the ground state. In this work, we employed ultrafast spectroscopy and computational methods to investigate the molecular origin of the coherent motion accompanying the photoisomerization of indanylidene–pyrroline (IP) molecular switches. UV/Vis femtosecond transient absorption gave evidence for an excited‐ and ground‐state vibrational wave packet, which appears as a general feature of the IP compounds investigated. In close resemblance to the coherent photoisomerization of rhodopsin, the sudden onset of a far‐red‐detuned and rapidly blue‐shifting photoproduct signature indicated that the population arriving on the electronic ground state after nonadiabatic decay through the conical intersection (CI) is still very focused in the form of a vibrational wave packet. Semiclassical trajectories were employed to investigate the reaction mechanism. Their analysis showed that coupled double‐bond twisting and ring inversions, already populated during the excited‐state reactive motion, induced periodic changes in π‐conjugation that modulate the ground‐state absorption after the non‐adiabatic decay. This prediction further supports that the observed ground‐state oscillation results from the reactive motion, which is in line with a biomimetic, coherent photoisomerization scenario. The IP compounds thus appear as a model system to investigate the mechanism of mode‐selective photomechanical energy transduction. The presented mechanism opens new perspectives for energy transduction at the molecular level, with applications to the design of efficient molecular devices.