bluuebunny/crossref_metadata_2025_split huggingface dataset:
All‐polymer solar cells utilizing low band gap polymers as donor and acceptor
Authors: Tang Yaqi , McNeill Christopher R. 
Published: December 2012

AbstractAll‐polymer solar cells based on blends of the low band gap polymers poly{[4,8‐bis[(2‐ethylhexyl)oxy]benzo[1,2‐b:4,5‐b′]dithiophene‐2,6‐diyl][3‐fluoro‐2‐[(2‐ethylhexyl)carbonyl]thieno[3,4‐b]thiophenediyl]} (PTB7) and poly{[N,N‐9‐bis(2‐octyldodecyl)‐naphthalene‐1,4,5,8‐bis(dicarboximide)‐2,6‐diyl]‐alt‐5,59‐(2,29‐bithiophene)} (P(NDI2OD‐T2)) are demonstrated. The use of the donor polymer PTB7 instead of poly(3‐hexylthiophene) results in a higher open‐circuit voltage and an overall spectral response better matched to the solar spectrum. A power conversion efficiency of 1.1% is reported with a peak external quantum efficiency of 18% at a wavelength of 680 nm. The microstructure of PTB7:P(NDI2OD‐T2) blends is also investigated using a combination of grazing‐incidence wide‐angle X‐ray scattering (GIWAXS), near‐edge X‐ray fine‐structure (NEXAFS) spectroscopy, atomic force microscopy (AFM), and scanning transmission X‐ray microscopy (STXM). GIWAXS measurements show that PTB7:P(NDI2OD‐T2) blends contain P(NDI2OD‐T2) crystallites with a (100) thickness of 9.5 nm dispersed in an amorphous PTB7 matrix. STXM measurements indicate a lack of mesoscale phase separation, with AFM and NEXAFS measurements revealing a P(NDI2OD‐T2)‐rich top surface with fibrillar morphology. These results indicate that the pairing of low band gap polymers as both donor and acceptor polymers in all‐polymer solar cells may be an effective strategy for realizing high‐efficiency all‐polymer solar cells. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013
Respiratory and hemodynamic effects of a stepwise lung recruitment maneuver in pediatric ARDS: A feasibility study
Authors: Cruces Pablo , Donoso Alejandro , Valenzuela Jorge , Díaz Franco 
Published: December 2012

AbstractBackgroundLittle is known about the efficacy and safety of recruitment maneuvers (RMs) in pediatric patients with acute respiratory distress syndrome (ARDS). We therefore assessed the effects on gas exchange and lung mechanics and the possible detrimental effects of a sequential lung RMs and decremental positive end‐expiratory pressure (PEEP) titration in pediatric ARDS patients.MethodsWe enrolled patients <15 years of age with ARDS, progressive hypoxemia, <72 hr of mechanical ventilation, and hemodynamic stability. A step‐wise RM and decremental PEEP trial were performed. Safety was evaluated as the occurrence of hypotension and low pulse oxymeter oxygen saturation during the maneuver and development of airleaks after. Efficacy was evaluated as changes in lung compliance (Cdyn) and gas exchange 1, 12, and 24 hr after the RM.ResultsWe included 25 patients, of median age 5 (1–16) months, median weight 7.0 (4.1–9.2) kg, median PaO2/FIO2 117 (96–139), and median Cdyn 0.48 (0.41–0.68) ml/cmH2O/kg at baseline. Thirty RM were performed, with all completed successfully. No airleaks developed. Mild hypotension was detected during four procedures. Following RM, Cdyn, and PaO2/FIO2 increased significantly (P < 0.01 each), without changes in PaCO2 (P = 0.4). A >25% improvement in lung function (Cdyn or PaO2/FIO2) was observed after 90% of the RM procedures. Gas exchange worsening over the next 24 hr resulted in HFOV use in 36% of patients, while the remaining subjects sustained improvements in oxygenation at 12 and 24 hr. The 28‐day mortality rate was 16%.ConclusionsSequential RMs were safe and well tolerated in hemodynamically stable children with ARDS. RMs and a decremental PEEP trial may improve lung function in pediatric patients with ARDS and severe hypoxemia. Pediatr Pulmonol. 2013; 48:1135–1143. © 2012 Wiley Periodicals, Inc.
Ion Chromatographic Analysis of Ammonium Dinitramide–Oxidizer for Propellant and Pyrotechnic Applications
Authors: Raghavan Rajeev , Jacob Salu 
Published: December 2012

AbstractAnalysis of ammonium dinitramide (ADN), the advance rocket propellant oxidizer, in pure form as well as in mixtures was carried out by ion chromatography (IC). The purity of ammonium dinitramide was directly determined by estimating the dinitramide ions and indirectly by estimating the impurities. Both methods gave results comparable with those determined by Differential Scanning Calorimetry and UV spectroscopy. The chemical composition of ADN in mixtures containing nitrate, chromate, chlorate, perchlorate, and thiocyanate ions was quantitatively estimated in the same solution without any interferences or prior separation of analyte ions. The newly developed ion chromatographic methods for the analysis of ADN are simple and fast with good accuracy and precision when compared to other analytical techniques. The IC methods are found to be highly suitable for quality control analysis of ADN containing compositions and for the online process monitoring of the formation of ADN in the reaction mixture.
The Effect of Ambient Conditions on the Burning Rate of Gel Fuel Droplets
Authors: Bar‐or Dory , Natan Benveniste 
Published: December 2012

AbstractAn experimental study was conducted to determine the dependence of the burning rate coefficient of gel fuel droplets on the pressure at different ambient oxygennitrogen mixtures. Experiments were conducted using a pressure chamber, in which the droplet was suspended and the combustion process was video‐photographed by a high‐speed digital video camera. The tests were conducted at pressures between 0.1–4 MPa at different ambient oxygennitrogen compositions (air, 40 % O2 – 60 % N2, and 60 % O2 – 40 % N2). The fuel was a compound of 95 % kerosene and 5 % gellant. At sub‐critical pressure conditions, the burning rate coefficient was found to increase with increasing ambient oxygen mass fraction. At supercritical conditions, no dependence of the burning rate coefficient on the ambient mixture was found. The results indicate that the burning rate coefficient depends on the oxygen partial pressure, at least at low pressures.
Induction of Pluripotent Stem Cells from Primordial Germ Cells by Single Reprogramming Factors
Authors: Nagamatsu Go , Kosaka Takeo , Saito Shigeru , Honda Hiroaki , Takubo Keiyo , Kinoshita Taisuke , Akiyama Hideo , Sudo Tetsuo , Horimoto Katsuhisa , Oya Mototsugu , Suda Toshio 
Published: December 2012

Abstract
Germ cells are similar to pluripotent stem cells in terms of gene expression patterns and the capacity to convert to pluripotent stem cells in culture. The factors involved in germ cell development are also able to reprogram somatic cells. This suggests that germ cells are useful tools for investigating the mechanisms responsible for somatic cell reprograming. In this study, the expression of reprograming factors in primordial germ cells (PGCs) was analyzed. PGCs expressed Oct3/4, Sox2, and c-Myc but not Klf4. However, Klf2, Klf5, Essrb, or Essrg, which were expressed in PGCs, could compensate for Klf4 during somatic cell reprograming. Furthermore, PGCs could be converted to a pluripotent state by infection with any of the known reprogramming factors (Oct3/4, Sox2, Klf4, and c-Myc). These cells were designated as multipotent PGCs (mPGCs). Contrary to differences in the origins of somatic cells in somatic cell reprogramming, we hypothesized that the gene expression levels of the reprogramming factors would vary in mPGCs. Candidate genes involved in the regulation of tumorigenicity and/or reprogramming efficiency were identified by comparing the gene expression profiles of mPGCs generated by the exogenous expression of c-Myc or L-Myc.
Activin Receptor-Like Kinase 5 Inhibition Reverses Impairment of Endothelial Cell Viability by Endogenous Islet Mesenchymal Stromal Cells
Authors: Clarkin Claire E. , King Aileen J. , Dhadda Paramjeet , Chagastelles Pedro , Nardi Nance , Wheeler-Jones Caroline P. , Jones Peter M. 
Published: December 2012

AbstractFollowing islet transplantation, islet graft revascularization is compromised due to loss of endothelial cells (ECs) during islet culture. TGF-β signaling pathways are essential for vascular homeostasis but their importance for islet EC function is unclear. We have identified a population of multipotent mesenchymal stromal cells (MSCs) within islets and investigated how modulation of TGF-β signaling by these cells influences islet EC viability. Cultured islets exhibited reduced expression of EC markers (VEGFR2, VE-cadherin and CD31), which was associated with diminished but sustained expression of endoglin a marker of both ECs and MSCs. Double fluorescent labeling of islets in situ with the EC marker CD31 disclosed a population of CD31-negative cells which were positive for endoglin. In vitro coculture of microvascular ECs with endoglin-positive, CD31-negative islet MSCs reduced VEGFR2 protein expression, disrupted EC angiogenic behavior, and increased EC detachment. Medium conditioned by islet MSCs significantly decreased EC viability and increased EC caspase 3/7 activity. EC:MSC cocultures showed enhanced Smad2 phosphorylation consistent with altered ALK5 signaling. Pharmacological inhibition of ALK5 activity with SB431542 (SB) improved EC survival upon contact with MSCs, and SB-treated cultured islets retained EC marker expression and sensitivity to exogenous VEGF164. Thus, endoglin-expressing islet MSCs influence EC ALK5 signaling in vitro, which decreases EC viability, and changes in ALK5 activity in whole cultured islets contribute to islet EC loss. Modifying TGF-β signaling may enable maintenance of islet ECs during islet isolation and thus improve islet graft revascularization post-transplantation.
Transection of the Liver Parenchyma With an Ultrasound Dissector or a Stapler Device: Results of a Randomized Clinical Study
Authors: Savlid Mats , Strand Angelica Horna , Jansson Anders , Agustsson Thorhallur , Söderdahl Gunnar , Lundell Lars , Isaksson Bengt 
Published: December 2012

AbstractBackgroundPerioperative hemorrhage and postoperative bile leakage are severe complications of liver surgery. They may be related to the techniques used to divide the tissue. We designed a randomized clinical trial to compare the cavitron ultrasonic surgical aspirator (CUSA) and an endoscopic stapler device applied in routine clinical hepatic surgical practice.MethodsAll consecutive patients admitted for elective hepatic resective surgery—at least bisegmentectomy of the liver—were assessed for enrollment in the study. A total of 100 patients were subsequently randomized. There was a good balance between the study groups concerning issues that may be of relevance for the perioperative and postoperative courses. The primary objective of the study was to achieve an approximately 25 % reduction in perioperative blood loss and postoperative bile leakage. Secondary outcome variables were operating time, general postoperative morbidity, length of hospital stay, and direct medical costs.ResultsThe amount of perioperative or postoperative blood loss did not differ significantly between the two groups. We observed a trend toward shorter transection and operating time for patients in whom staplers were used, but the difference did not reach statistical signifcance. The postoperative courses were close to identical in the respective study arms with no difference in bile leakage rates or in the total morbidity profiles. The direct medical costs were nonsignificantly lower in the group where staplers were used for liver transection.ConclusionsThe results show that the use of endoscopic vascular staplers in liver surgery is feasible and safe. It offers an attractive alternative for division of the liver parenchyma during routine hepatic surgery, being comparable to the use of CUSA without adding extra costs.
Utilisation of a Level 1 Trauma Centre in KwaZulu‐Natal: Appropriateness of Referral Determines Trauma Patient Access
Authors: Hardcastle Timothy Craig , Reeds Matthew Giles , Muckart David James Jackson 
Published: December 2012

AbstractBackgroundAppropriate referral of major trauma patients to an accredited Level 1 Trauma facility is associated with improved outcome. A new Level 1 Trauma Centre was opened at Inkosi Albert Luthuli Central Hospital in March 2007. This study sought to audit the referral pattern of external consults to the trauma unit and ascertain whether the unit was receiving appropriate referrals and has adequate capacity.MethodsAn audit was performed of the referral proformas used in the unit to record admission decisions and of the computerised trauma database. The audit examined referral source (scene vs. interhospital), regional distribution, and final decision regarding admission of the injured patients. The study was approved by the UKZN Ethics Committee (BE207/09 and 011/010).ResultsOf the 1,212 external consults, 540 were accepted for admission while the rest were not accepted for various reasons. These included 206 cases where no bed was available, 233 did not meet admission criteria (minor injury or futile situation), and 115 were for subspecialty management of a single‐system injury. Finally, 115 were initially refused pending stabilisation for transfer at a regional facility. Twenty‐six percent of the cases were referrals from the scene, with an acceptance rate of 96 %. Most patients (59 %) were from the local eThekwini region.ConclusionMajor multiorgan system trauma remains a significant public health burden in KwaZulu‐Natal. A Level 1 Trauma Service is used appropriately in most circumstances. However, the additional need for more hospital facilities that provide such services across the whole province to enable effective geographical coverage for those trauma patients requiring such specialised trauma care is essential.
Management of Recurrent Inguinal Hernia at a Tertiary Care Hospital of Southern Sindh, Pakistan
Authors: Memon Ahmer A. , Siddiqui Faisal G. , Abro Arshad H. , Agha Ahmed H. , Lubna Shahzadi , Memon Abdul S. 
Published: December 2012

AbstractBackgroundThe goal of the present study was to determine the frequency, mode of presentation, and need for reoperation in the treatment of recurrent inguinal hernia at Liaquat University Hospital, Jamshoro, Sindh, Pakistan.MethodsThis descriptive, cross‐sectional study was conducted over a period of four years, from January 2007 through December 2010. A total of 916 patients with inguinal hernia underwent operation in the Department of Surgery at Liaquat University Hospital Jamshoro, Sindh, Pakistan, during the study period. Of them, 62 patients were diagnosed to have recurrent inguinal hernia and were included in the study. Female patients and patients with other types of hernia like femoral, epigastric, and paraumbilical defects were excluded.ResultsAmong the 62 patients studied, the commonest age group with recurrence was 41–50 years (43.5 %). Fifty‐one (82.2 %) of the patients were ambulatory workers. In 47 cases (75.8 %) recurrence was on the right side, and in 15 (24.1 %) recurrence was on the left side. First time recurrence was seen in 54 patients (87 %) and second time recurrence was seen in 7 patients (11.2 %); third time recurrence was observed in only one patient. All of these patients had an initial open surgery without mesh, except one. Bassini’s repair was done as a primary repair in 47 (75.8 %) cases. A total of 11 patients (17.7 %) had no previous medical records. Darning repair was done in 3 patients (4.8 %), and open surgery with mesh was performed in only one patient. The highest recurrence rates were seen in patients whose hernia repairs had been done by postgraduate trainees. That is, 45 of the patients requiring reoperation (72.5 %), compared to 11 (17.7 %), and 6 (9.6 %) operations performed by registrars and consultants, respectively. All patients in our study underwent tension‐free Lichtenstein mesh repair. Postoperative complications included retention of urine (40.3 %), scrotal hematoma (6.4 %), and wound infection (3.2 %).ConclusionsRecurrent inguinal hernia is still frequently observed today, and the Lichtenstein tension‐free repair has gained great acceptance worldwide and is currently considered the procedure of choice for primary and recurrent inguinal hernias.
How Neighborhood Structural and Institutional Features Can Shape Neighborhood Social Connectedness: A Multilevel Study of Adolescent Perceptions
Authors: Lenzi Michela , Vieno Alessio , Santinello Massimo , Perkins Douglas D. 
Published: December 2012

AbstractAccording to the norms and collective efficacy model, the levels of social connectedness within a local community are a function of neighborhood structural characteristics, such as socioeconomic status and ethnic composition. The current work aims to determine whether neighborhood structural and institutional features (neighborhood wealth, percentage of immigrants, population density, opportunities for activities and meeting places) have an impact on different components of neighborhood social connectedness (intergenerational closure, trust and reciprocity, neighborhood‐based friendship and personal relationships with neighbors). The study involved a representative sample of 389 early and middle adolescents aged 11–15 years old, coming from 31 Italian neighborhoods. Using hierarchical linear modeling, our findings showed that high population density, ethnic diversity, and physical and social disorder might represent obstacles for the creation of social ties within the neighborhood. On the contrary, the presence of opportunities for activities and meeting places in the neighborhood was associated with higher levels of social connectedness among residents.
Dufour and Soret Effects in an Axisymmetric Stagnation Point Flow of Second Grade Fluid with Newtonian Heating
Authors: Nawaz M. , Alsaedi A. , Hayat T. , Alhothauli M. S. 
Published: December 2012

ABSTRACTThe problem of magnetohydrodyanmic stagnation point flow and heat transfer of second grade fluid past a radially stretching sheet is investigated. The flow problems are examined in the presence of Newtonian heating and Soret and Dufour effects. The relevant mathematical problems are developed through equations of continuity, momentum, energy and concentration. The reduced differential equations are solved for the convergent series solutions. In order to validate the homotopy analysis method (HAM), a comparative study between the present and previous results is made. It is observed that Dufour and Soret effects on temperature and concentration distributions are different. Qualitatively, the influence of Prandtl number on temperature and Schmidt number on concentration is similar. It is further noted that the diffusion of solute in second grade fluid is increasing function of Soret number whereas it decreases when Dufour number increases.
The city as a transient home: residential patterns of Moscow workers around the turn of the twentieth century
Authors: MAZANIK ANNA 
Published: December 2012

ABSTRACT:This article examines the social topography and the housing patterns of Moscow workers in the context of their social status and experience of immigration. It argues that in the early twentieth century Moscow was characterized by extremely poor housing conditions and the absence of clear residential segregation of social classes due to the lack of profound planning policy and urban reforms.
The Speaker of the House: A Study of Leadership. By Matthew N. Green
Authors: Beckmann Matthew N. 
Published: December 2012

The Speaker of the House: A Study of Leadership. By Matthew N. Green. New Haven: Yale University Press, 2010. 292p. $30.00.In his book, Matthew N. Green investigates Speakers' purposive goals, tactical options, and legislative influence. The overriding thesis: Speakers' actions do not simply reflect “the majority of the majority's” interests and preferences, but rather emerge from a more diverse set of goals. As Green argues: “Speakers may exercise legislative leadership on behalf of the preferences of others besides the majority party in Congress [including] representing his or her own district … achieving his or her own preferred policy outcome … helping the party's president, the institutional presidency, or the House as a whole” (p. 17).
Nonviolent Revolutions: Civil Resistance in the Late 20th Century. By Sharon Erickson Nepstad
Authors: Pearlman Wendy 
Published: December 2012

Nonviolent Revolutions: Civil Resistance in the Late 20th Century. By Sharon Erickson Nepstad. New York: Oxford University Press, 2011. 200p. $99.00 cloth, $24.95 paper.We live in nonviolent revolutionary times. From Egypt to Moscow, New York to Manama, 2011 saw millions of peaceful protestors take to the streets to demand change. Under what conditions do civilian-based struggles achieve their goals without resort to violence?
Neoliberalism, Race, and the American Welfare State
Authors: Boettke Peter J. 
Published: December 2012

Disciplining the Poor: Neoliberal Paternalism and the Persistent Power of Race. By Joe Soss, Richard C. Fording, and Sanford F. Schram. Chicago: University of Chicago Press, 2011. 368p. $75.00 cloth, $25.00 paper.It is more than 15 years since the Personal Responsibility and Work Opportunity Act was passed in 1996, famously described by then-President Bill Clinton as “the end of welfare as we know it.” In Disciplining the Poor, Joe Soss, Richard Fording, and Sanford Schram analyze recent changes in US welfare policy as reflections of broader transformations of the “governance” of poverty, arguing that these transformations represent a new form of “neoliberal paternalism” in which race continues to be an important element. In this symposium, a diverse group of political scientists working on welfare issues have been asked to critically assess the book's account and to comment more broadly on the importance of the “governance of poverty” to the future of American politics.—Jeffrey C. Isaac, Editor
Neoliberalism, Race, and the American Welfare State
Authors: Katzenstein Mary Fainsod 
Published: December 2012

Disciplining the Poor: Neoliberal Paternalism and the Persistent Power of Race.By Joe Soss, Richard C. Fording, and Sanford F. Schram. Chicago: University of Chicago Press, 2011. 368p. $75.00 cloth, $25.00 paper.It is more than 15 years since the Personal Responsibility and Work Opportunity Act was passed in 1996, famously described by then-President Bill Clinton as “the end of welfare as we know it.” InDisciplining the Poor, Joe Soss, Richard Fording, and Sanford Schram analyze recent changes in US welfare policy as reflections of broader transformations of the “governance” of poverty, arguing that these transformations represent a new form of “neoliberal paternalism” in which race continues to be an important element. In this symposium, a diverse group of political scientists working on welfare issues have been asked to critically assess the book's account and to comment more broadly on the importance of the “governance of poverty” to the future of American politics.—Jeffrey C. Isaac, Editor