bluuebunny/crossref_metadata_2025 huggingface dataset:
Translating Research and Surveillance into Action
Authors: Loschen Wayne
Published: May 2014

The International Society for Disease Surveillance (ISDS) will hold its twelfth annual conference in New Orleans on December 12th and 13th, 2013. Led by the Society’s mission to improve population health by advancing the science and practice of disease surveillance, the conference brings together researchers and practitioners in public health, epidemiology, health policy, biostatistics and mathematical modeling, informatics, computer science, and related fields focused on biosurveillance and emerging challenges to public health practice. The theme of this year’s conference, Translating Research and Surveillance into Action, promotes the activities that are making a difference in the public health community. With abstracts submitted by authors from 36 countries, the conference will highlight research and successes in practice from around the world.Of the 211 abstracts submitted to the conference, 66 were chosen for oral presentation, 80 for posters, 4 for roundtable discussions, 4 for panels and 28 for a new presentation type, lightning talks. With 14 talks in 2 separate sessions, lightning talks will provide the audience with an information-packed series of 5 minute presentations. They will include themes like how to best use social media, what types of surveillance were performed during the 2013 Super Bowl, what algorithms work best for detection of outbreaks in resource-limited countries, and many other fantastic topics.In keeping with the conference theme of action, and due to the increasing frequency of major events requiring public health response (such as extreme weather and terrorist bombings), we are grateful to have Dr. David Abramson provide the opening keynote. Dr. Abramson is the deputy director of the National Center for Disaster Preparedness and can offer insight into how public health surveillance can be used before, during, and after disasters.We are also very pleased to have Dr. Gary Slutkin, the founder and executive director of the Cure Violence organization, speak at the conference. Dr. Slutkin will discuss his organization’s fascinating use of epidemiologic techniques applied to the problem of reducing gang violence in inner cities. We look forward to hearing their experience and the challenge of thinking about epidemiology and surveillance in a new light.I am looking forward to the 2013 ISDS Conference – it is one of the few places where public health practice, analytics, information technology, and policy seamlessly merge in a meaningful way. Every year I listen to inspiring success stories of surveillance practice, intriguing informatics techniques, brilliant analytical methods, and thoughtful policy discussions. And while all of those topics are remarkable by themselves, they are surpassed by the amazing people I meet and the connections that I make every year at ISDS!
Redescription of Tapinesthis inermis (Araneae, Oonopidae), with detailed information on its ultrastructure
Authors: Henrard Arnaud , Jocqué Rudy , Baehr Barbara C.
Published: May 2014

Tapinesthis inermis Simon, 1882, the only species in the genus, is widely distributed in western Europe. This redescription provides the first information on the ultrastructure of the species using SEM. The morphology of the spinnerets, tarsal claws and tarsal organs, and the internal structure of the female genitalia and the male palp are described and illustrated in detail. The combination of these structures is very similar to those encountered in some dysderoid spiders and supports the basal placement of Tapinesthis among Oonopinae. The phylogenetic relationships of the species are discussed. The only female among the three syntypes is designated as the lectotype.
Application of Cox’s Proportional Hazard Model and Construction of Life Table for Under-Five
Authors: Shantikumar Salam Singh
Published: May 2014

A primary data of 836 eligible women in the age group of 15-49 years is used to determine the causal effects of covariates on under-five mortality. The eight covariates viz., number of family members (NHM), type of toilet facility (TTF), total children ever born (TCB), parity (PAR), duration of breastfeeding (DBF), use contraceptive (CMT), DPT and ideal number of girl (ING) are considered as covariates of the study. By applying Cox’s regression analysis, six covariates viz., TTF, NHM, CMT, DBF, DPT and ING have substantially and significantly effect on under-five mortality. Further, a life table of under-five children under study is constructed using the estimate of survival function obtained from Cox’s regression model.
Efficient Blockwise Permutation Tests Preserving Exchangeability
Authors: Zhou Chunxiao , Zwilling Chris E. , Calhoun Vince D. , Wang Michelle Y.
Published: May 2014

In this paper, we present a new blockwise permutation test approach based on the moments of the test statistic. The method is of importance to neuroimaging studies. In order to preserve the exchangeability condition required in permutation tests, we divide the entire set of data into certain exchangeability blocks. In addition, computationally efficient moments-based permutation tests are performed by approximating the permutation distribution of the test statistic with the Pearson distribution series. This involves the calculation of the first four moments of the permutation distribution within each block and then over the entire set of data. The accuracy and efficiency of the proposed method are demonstrated through simulated experiment on the magnetic resonance imaging (MRI) brain data, specifically the multi-site voxel-based morphometry analysis from structural MRI (sMRI).
Efeitos pleiotrópicos das estatinas na sepse
Authors: Giusto Silvana Menegoto Nogueira Di , Queiroz Kelly Cristina Batista de Souto , Raimundo Rodrigo Daminello , Abreu Luiz Carlos de , Sato Mônica Akemi
Published: May 2014

O objetivo do presente estudo foi revisar os efeitos da terapia com estatinas em pacientes com quadro de sepse. Foi realizada uma busca bibliográfica de artigos na base de dados MEDLINE/PubMed, SciELO e LILACS, no período de publicação delimitado entre 2009 e 2013. Foram incluídos artigos referentes a ensaios clínicos randomizados controlados e estudos de coorte observacionais clínicos. Foram encontrados diversos estudos clínicos e observacionais que investigaram o efeito do uso de estatinas em infecções e em sepse, tanto de uso contínuo pré-hospitalar (com ou sem interrupção durante internação) ou com início imediato pós-internação. Alguns estudos descrevem prováveis efeitos positivos e benéficos da terapia com estatinas no quadro de sepse, dentre eles a melhora dos parâmetros inflamatórios e da taxa de mortalidade, porém, esses resultados não se sustentam quando são aplicados métodos estatísticos que levam em conta diferentes variáveis, tais como idade, sexo, comorbidades e gravidade da doença. Até o momento nenhum estudo demonstrou evidências sólidas e significativas quanto à redução de mortalidade e morbidade no quadro séptico associado ao uso de estatinas, indicando que seu efeito benéfico e protetor ainda não foi plenamente delimitado, sendo necessários mais estudos que confirmem os resultados até agora encontrados.
Resultados do tratamento cirúrgico das fraturas do rádio distal: estudo clínico com técnica de osteossíntese percutânea e minimamente invasiva
Authors: Aita Márcio Aurélio , Ikeuti Douglas Hideki , Mota Rodrigo Toledo , Moraes Guilherme Bonadia Bueno de , Credidio Marcos Vinícius , Costa Eduardo Fernandes da , Carvalho Fernando Luvizotto
Published: May 2014

Introdução: A utilização de técnicas minimamente invasivas para o tratamento de fraturas do rádio distal teve um aumento significativo nos últimos três anos. Isso é explicado devido ao aumento na incidência de fraturas em pacientes economicamente ativos e à necessidade destes retornarem precocemente ao trabalho. Objetivo: Analisar os resultados clínico-funcionais dos pacientes com diagnóstico de fratura com desvio redutível e instável da extremidade distal do rádio submetidos ao tratamento cirúrgico pela técnica de osteossíntese percutânea e minimamente invasiva utilizando haste intramedular bloqueada. Métodos: Foram avaliados 53 pacientes submetidos ao tratamento cirúrgico da fratura da extremidade distal do rádio, redutível e instável, classificadas segundo Rayhack como Tipo IIB, pelo método minimamente invasivo, com haste intramedular bloqueada no período entre janeiro de 2011 e dezembro de 2012. O tempo de seguimento foi de seis a 24 meses, avaliando periodicamente parâmetros radiográficos, dor, medida do arco de movimento, força de preensão palmar e qualidade de vida através do questionário DASH. Resultados: Através da análise dos valores obtidos observamos uma melhora estatisticamente significante em todos os parâmetros clínicos analisados. O grau de força de preensão palmar e a medida do arco de movimento apresentaram melhora importante desde a terceira semana de pós-operatório, assim como a escala de dor e a avaliação do questionário DASH. Conclusão: A técnica minimamente invasiva é eficaz e segura, com melhora clínica e funcional e apresenta resultados superiores quando comparada a outros métodos descritos na literatura.
Estilo de vida relacionado à saúde de estudantes universitários: comparação entre ingressantes e concluintes
Authors: Santos Jefferson Jovelino Amaral dos , Saracini Nicole , Silva Watusi Camila da , Guilherme Juliane Honório , Costa Telma Aparecida da , Gonçalves e Silva Maria-Raquel De Assunção
Published: May 2014

Introdução: O estilo de vida na juventude desempenha um papel significativo na prevenção de doenças e na promoção da saúde durante todo o ciclo de vida de um indivíduo. Objetivo: Analisar o estilo de vida de estudantes universitários de uma instituição privada de ensino superior brasileira, bem como as diferenças entre os acadêmicos ingressantes e concluintes. Métodos: Participaram do estudo 720 alunos universitários divididos em dois grupos: ingressantes (n=399) e concluintes (n=321). Foram avaliadas medidas antropométricas como peso, estatura e índice de massa corporal (IMC), além de variáveis sociodemográficas como gênero, raça, renda e estado civil. O estilo de vida foi mensurado através do Questionário Fantástico de Estilo de Vida, um questionário autoadministrado e devidamente validado. Os dados foram analisados pela estatística descritiva e posteriormente pelo teste t de Student para amostras independentes. Resultados: Os indivíduos ingressantes apresentaram um IMC menor que os concluintes (22,5±3,68 kg/m2 e 23,30±3,87 kg/m2, respectivamente). Os valores obtidos nos escores da variável estilo de vida não foram diferentes entre os grupos quando avaliados globalmente. Porém, quando os domínios foram avaliados individualmente, os ingressantes obtiveram melhores resultados nos níveis de atividade física, na questão de dirigir e conduzir veículo automotor sob efeito de bebidas alcóolicas e agitação. Conclusão: O estudo ressalta a importância da orientação de estudantes universitários para um estilo de vida saudável e da disponibilização de programas de atividades físicas no ambiente visando o controle de peso até os últimos anos de estudo, visto serem os concluintes o grupo de maior tendência ao sobrepeso.
Integrating parsimonious models of hydrological connectivity and soil biogeochemistry to simulate stream DOC dynamics
Authors: Birkel Christian , Soulsby Chris , Tetzlaff Doerthe
Published: May 2014

To improve understanding and prediction of dissolved organic carbon (DOC) sources and fluxes in northern peat‐dominated catchments, we present the development and application of a parsimonious tracer‐aided rainfall‐runoff model coupled with a biogeochemistry subroutine able to concurrently simulate streamflow and DOC dynamics. The modeling approach which included quantitative assessment of associated uncertainties was conditioned by geochemical tracers which discriminate dominant water sources. Integration of DOC was predicated on statistical time series models which identified air temperature and streamflow as the key proxies that capture DOC supply and transport processes in two upland catchments in Scotland, UK. Conceptualizing the nonlinear partitioning of quick near‐surface and slower groundwater runoff sources in combination with a DOC mass balance resulted in a coupled, low‐parameter mechanistic model. Model tests showed mostly sensitive parameters and reasonable simulation results with seasonally controlled DOC supply and event‐based DOC transport. Transport is facilitated even for smaller events by overland flow from saturated histosols connected to the stream network. However, during prolonged dry periods, near‐surface runoff “switches off” and stream DOC is dominated by low concentration groundwaters. Furthermore, the model was able to explain subtle differences in DOC dynamics between the two catchments mainly reflecting the distribution of saturated soils and available storage. We conclude that tracers and statistical time series models can successfully guide the development of parsimonious yet structurally consistent water quality models. Parsimonious models provide tools for estimating DOC dynamics and loads with reduced uncertainty and potentially greater transferability.
Photoactive Electrodes Incorporating Electrosprayed Bacterial Reaction Centers
Authors: Mirvakili Seyed M. , Slota Joanna E. , Usgaocar Ashwin R. , Mahmoudzadeh Ali , Jun Daniel , Mirvakili Mehr Negar , Beatty J. Thomas , Madden John D. W.
Published: May 2014

Highly efficient light absorption and charge separation within the photosystem and reaction center (RC) complexes of photosynthetic plants and bacteria are of great interest for solar cell and photo detector applications, since they offer almost unity quantum yield and expected ultimate power conversion efficiencies of more than 18% and 12%, respectively. In addition, the charge separated states created by these protein complexes are very long lived compared to conventional semiconductor solar cells. In this work, a novel technique is presented for the deposition of photosynthetic protein complexes, by electrospraying RCs of Rhodobacter sphaeroides onto highly ordered pyrolytic graphite (HOPG) electrodes. Remarkably, it is shown that the RCs not only survive exposure to the high electric fields but also yield peak photocurrent densities of up to 7 μA cm−2, which is equal to the highest value reported to date.
Exome sequencing identifies compound heterozygous mutations in C12orf57 in two siblings with severe intellectual disability, hypoplasia of the corpus callosum, chorioretinal coloboma, and intractable seizures
Authors: Platzer Konrad , Hüning Irina , Obieglo Carolin , Schwarzmayr Thomas , Gabriel Rainer , Strom Tim M. , Gillessen‐Kaesbach Gabriele , Kaiser Frank J.
Published: May 2014

In patients with genetically heterogeneous disorders such as intellectual disability or epilepsy, exome sequencing is a powerful tool to elucidate the underlying genetic cause. Homozygous and compound heterozygous mutations in C12orf57 have recently been described to cause an autosomal recessive syndromic form of intellectual disability, including agenesis/hypoplasia of the corpus callosum, optic coloboma, and intractable seizures. Here, we report on two siblings from nonconsanguineous parents harboring two compound heterozygous loss‐of‐function mutations in C12orf57 identified by exome sequencing, including a novel nonsense mutation, and review the patients described in the literature. © 2014 Wiley Periodicals, Inc.
Clinical correlates and genetic linkage of social and communication difficulties in families with obsessive–compulsive disorder: Results from the OCD Collaborative Genetics Study
Authors: Samuels Jack , Shugart Yin Yao , Wang Ying , Grados Marco A. , Bienvenu O. Joseph , Pinto Anthony , Rauch Scott L. , Greenberg Benjamin D. , Knowles James A. , Fyer Abby J. , Piacentini John , Pauls David L. , Cullen Bernadette , Rasmussen Steven A. , Stewart S. Evelyn , Geller Dan A. , Maher Brion S. , Goes Fernando S. , Murphy Dennis L. , McCracken James T. , Riddle Mark A. , Nestadt Gerald
Published: May 2014

Some individuals with obsessive–compulsive disorder (OCD) have autistic‐like traits, including deficits in social and communication behaviors (pragmatics). The objective of this study was to determine if pragmatic impairment aggregates in OCD families and discriminates a clinically and genetically distinct subtype of OCD. We conducted clinical examinations on, and collected DNA samples from, 706 individuals with OCD in 221 multiply affected OCD families. Using the Pragmatic Rating Scale (PRS), we compared the prevalence of pragmatic impairment in OCD‐affected relatives of probands with and without pragmatic impairment. We also compared clinical features of OCD‐affected individuals in families having at least one, versus no, individual with pragmatic impairment, and assessed for linkage to OCD in the two groups of families. The odds of pragmatic impairment were substantially greater in OCD‐affected relatives of probands with pragmatic impairment. Individuals in high‐PRS families had greater odds of separation anxiety disorder and social phobia, and a greater number of schizotypal personality traits. In high‐PRS families, there was suggestive linkage to OCD on chromosome 12 at marker D12S1064 and on chromosome X at marker DXS7132 whereas, in low‐PRS families, there was suggestive linkage to chromosome 3 at marker D3S2398. Pragmatic impairment aggregates in OCD families. Separation anxiety disorder, social phobia, and schizotypal personality traits are part of a clinical spectrum associated with pragmatic impairment in these families. Specific regions of chromosomes 12 and X are linked to OCD in high‐PRS families. Thus, pragmatic impairment may distinguish a clinically and genetically homogeneous subtype of OCD. © 2014 Wiley Periodicals, Inc.
Unterhaltungsbaggerung für die Binnenschifffahrt
Authors: Groß Thomas , Wilms Michael
Published: May 2014

Zur Sicherung der Leichtigkeit der Schifffahrt und der Verkehrssicherheit sind in Deutschland auf den Binnenwasserstraßen sowie in Häfen und sonstigen Gewässern umfangreiche Unterhaltungsarbeiten in Form von Nassbaggerungen notwendig. Hier werden die verschiedenen Methoden nach dem Stand der Technik sowie die heutigen technischen Hilfsmittel zur Ausführung der Arbeiten aufgezeigt und bewertet.

Dredging for inland shipping – Maintain riverbed clearance by dredging and handling of dredged spoil

In order to secure and ease inland shipping maintenance of inland waterways, harbours and other inland waters via dredging is required. Various methods for doing this work and the technical resources are shown and benchmarked.
Leg cramps in pregnancy caused by chronic compartment syndrome and relieved by fasciotomy after childbirth
Authors: Orlin Jan Roar , Øen Jarle , Andersen John Roger , Tjugum Ivar Jostein , Westbye Hans Jacob , Roska Jomar , Aasved Helene , Hjelmeland Kjersti
Published: May 2014

Key Clinical Message

A case of intolerable leg pain in pregnancy, caused by Chronic Compartment Syndrome (CCS), is presented. Increasing amounts of opioids were given throughout the pregnancy. Anesthetical dilemmas and surgery are discussed. In conclusion, early surgery rather than opioids is recommended.
Imaging of hemorrhagic stroke in magnetic induction tomography: An in vitro study
Authors: Mamatjan Yasin
Published: May 2014

Magnetic Induction Tomography (MIT) has the potential of providing an inexpensive medical device for regular screening and monitoring of patients. MIT could be used to detect hemorrhagic stroke, if high measurement accuracy and spatial resolution can be reached to allow significant contrast between normal brain tissues and hemorrhaged areas. However, this can be challenging because spatial resolution in MIT is limited due to the small number of independent measurements, the inverse problems are severely ill‐posed, and erroneous data cause large artefacts in reconstructed images and lower the detectability threshold of bleeding. The noise components degrading signal and image quality may be caused by thermal drift and noise from acquisition systems, environment or by body movements. The objective of the article is to empirically investigate hemorrhagic stroke in MIT based on in vitro study and to improve stroke detectability and visibility to help monitoring stroke patients. The following approaches were evaluated: (i) level setting, (ii) improved spatial filtering, (iii) averaging of multiple measurements, (iv) the combinations of these three approaches, and (v) wavelet denoising. They were evaluated with an in vitro phantom resembling a cerebral stroke in a pig brain. The results showed that these approaches enhanced stroke visibility, lowered stroke detectability threshold from 15 ml to 5 ml, and improved the localization of phantom hemorrhages such that their combination produced the best results. These methods may make it easy to the estimation of actual stroke volume, and clinical interpretation, and it can be used to long‐term monitoring of stroke progression. © 2014 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 24, 161–166, 2014
Dimensional scalable lossless compression of MRI images using haar wavelet lifting scheme with EBCOT
Authors: Anusuya V. , Srinivasa Raghavan V.
Published: May 2014

Modern medical imaging requires storage of large quantities of digitized clinical data. To provide high bandwidth and to reduce the storage space, a medical image must be compressed before transmission. One of the best image compression techniques is using the Haar wavelet transform. The method of discrete cosine transform (DCT) is chosen to be the preprocessing scheme to identify the image frequency information and has excellent energy compaction property. The block coding algorithm uses a wavelet transform to generate the sub band samples, which can be quantized and coded. It is more robust to errors than many other wavelet‐based schemes. In this article, simulations are carried out on different medical Images and it demonstrates the performance in terms of peak signal to noise ratio (PSNR) & bits per pixel (BPP). Our proposed method is found to preserve information fidelity while reducing the amount of data. © 2014 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 24, 175–181, 2014
Renal intraspecific variation along an aridity gradient detected by new renal indices in a desert herbivorous rodent
Authors: Tejo Riquelme Patricia A. , Diaz Isenrath Gabriela B. , Andino Natalia , Borghi Carlos E.
Published: May 2014

Mammals that live in arid and semi‐arid environments in South America present physiological mechanisms that enable them to conserve water. Body water is lost through the kidneys, lungs, skin, and intestines. Regarding renal adaptation for water conservation, several indices have been used to estimate the capacity of the kidneys to produce a maximum urine concentration. Most studies were conducted at an inter‐specific level, with only few performed at the intraspecific level. In this work, we compare renal function and morphology among five populations of Southern mountain cavy, Microcavia australis, present along an aridity gradient. We hypothesized that individuals from drier zones would present morphological and functional renal modifications that imply a greater capability to conserve body water. These features were studied considering the classical indices (RMT, PMT, PMA, and RMA) and three new indices that consider area measurements; the latter showed to be more adequate to reflect intraspecific differences. Our results suggest that the morphological modifications of kidneys, that is, the greater areas of renal inner medulla, would be related to the aridity gradient where populations of Southern mountain cavy occur. J. Exp. Zool. 321A: 348–356, 2014. © 2014 Wiley Periodicals, Inc.
Nonvertex‐Balanced Factors in Random Graphs
Authors: Gerke Stefanie , McDowell Andrew
Published: May 2014

We prove part of a conjecture by Johansson, Kahn, and Vu (Factors in random graphs, Random Struct. Algorithms 33 (2008), 1, 1–28.) regarding threshold functions for the existence of an H‐factor in a random graph . We prove that the conjectured threshold function is correct for any graph H which is not covered by its densest subgraphs. We also demonstrate that the main result of Johansson, Kahn, and Vu (Factors in random graphs, Random Struct. Algorithms 33 (2008), 1, 1–28) generalizes to multigraphs, digraphs, and a multipartite model.
Clinical value of spleen‐preserving distal pancreatectomy: a case‐matched analysis with a special emphasis on the postoperative systemic inflammatory response
Authors: Dumitrascu Traian , Dima Simona , Stroescu Cezar , Scarlat Andra , Ionescu Mihnea , Popescu Irinel
Published: May 2014

Background

The impact of splenectomy on outcomes after distal pancreatectomy was assessed in the present study, with a special emphasis on the postoperative systemic inflammatory response.

Methods

Thirty‐three patients with spleen‐preserving distal pancreatectomy—Kimura technique (SPDP group) were compared with a group of distal pancreatectomies with splenectomy (DPS group). The two groups were 1:1 matched for age, gender, co‐morbidities and pathology.

Results

No differences between the groups were observed regarding the overall/severe/infectious morbidity, pancreatic fistulae and postoperative diabetes rates (P‐values ≥ 0.475). An increased blood loss (P = 0.031) and need for intraoperative transfusions (P = 0.004) was observed in the DPS group. Postoperative platelet count and platelet‐to‐lymphocyte ratio were significantly higher in the DPS group (P < 0.001).

Conclusion

Spleen removal during DP is not associated with a higher morbidity but with an increased blood loss and need for intraoperative transfusions. Although the postoperative systemic inflammatory response is higher when the splenectomy is performed, the number of postoperative infectious complications is not influenced. Preservation of the spleen during DP for benign and low‐grade malignant tumor of the distal pancreas appears to be worthy and should be the first option whenever is technically feasible and it can be safely achieved.
SUPERVISION IN SCHOOL PSYCHOLOGY: THE DEVELOPMENTAL/ECOLOGICAL/PROBLEM‐SOLVING MODEL
Authors: Simon Dennis J. , Cruise Tracy K. , Huber Brenda J. , Swerdlik Mark E. , Newman Daniel S.
Published: May 2014

Effective supervision models guide the supervisory relationship and supervisory tasks leading to reflective and purposeful practice. The Developmental/Ecological/Problem‐Solving (DEP) Model provides a contemporary framework for supervision specific to school psychology. Designed for the school psychology internship, the DEP Model is also applicable to all pre‐service and advanced field‐based training, as well as career‐long continuing professional development. The Developmental domain initiates training at the functioning skill level of the supervisee and progresses toward independent competency. The Ecological domain addresses the multiple systemic contexts that influence school psychology practice and prepares the intern to intervene within both individual and systemic contexts. The Problem‐Solving domain focuses on the application of data‐based decision making and evidence‐based interventions to the full range of school psychology activities. It provides a systematic schema to address student, family, and school needs.
Suppressing charge recombination by incorporating 3,6‐carbazole into poly[9‐(heptadecan‐9‐yl)‐9H‐carbazole‐2,7‐diyl‐alt‐(5,6‐bis‐(octyloxy)‐4,7‐di(thiophen‐2‐yl)benzo[1,2,5]‐thiadiazole)‐5,5‐diyl]
Authors: Lee Gang‐Young , Moon Byung‐Joon , Song Seulki , Lee Won Ho , Woo Han Young , Park Taiho
Published: May 2014

A series of poly[9‐(heptadecan‐9‐yl)‐9H‐carbazole‐2,7‐diyl‐alt‐(5,6‐bis‐(octyloxy)‐4,7‐di(thiophen‐2‐yl)benzo‐[1,2,5]‐thia‐diazole)‐5,5‐diyl] compositions containing various ratios of 3,6‐carbazole was synthesized for testing in a polymer solar cell. An appropriate amount of 3,6‐carbazole units incorporated into the copolymer improved intermolecular charge transport, whereas excess amount of 3,6‐carbazole units temporarily seized on the partial negative charge generated in the conjugation breaks. We extensively studied the effects of the incorporated 3,6‐carbazole units on the intermolecular interactions, which can affect nongeminated recombination in bulk heterojunction‐polymer solar cells. These properties were investigated using photocurrent‐ and light intensity‐dependent measurements and electrochemical impedance spectroscopy. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 2047–2056
Optimized bandwidth allocation in broadband wireless access networks
Authors: Nasser Nidal , Miller Reid , Esmailpour Amir , Taha Abd‐Elhamid M. , Bejaoui Tarek
Published: May 2014

Towards satisfying the requirements of International Mobile Telecommunications–Advanced, both the Institute of Electrical and Electronics Engineers (IEEE) and Third Generation Partnership Project (3GPP) introduced revolutionary wireless technologies, exploiting advanced technologies and architectures. Both IEEE's 802.16 (Worldwide Interoperability for Microwave Access (WiMAX)) and 3GPP's Long Term Evolution have been introduced to accommodate the increasing demand for mobile services and applications. To realize the true potential of these technologies, however, opportunistic frameworks for radio resource management must be designed to exploit the adaptive nature of mobile traffic. The utility optimized quality‐of‐service (QoS) framework proposed in this paper for the mobile WiMAX networks achieves this objective. To maintain support for QoS guarantees, the framework capitalizes on the adaptive nature of WiMAX traffic by individually linking connections with a utility function designed to both uphold the end users’ perceived performance and determine bandwidth allocations by a search tree maximization algorithm. In doing so, bandwidth utilization is maximized for all active connections, and blocking and dropping probabilities for new and handover calls, respectively, are minimized. The framework is evaluated through an extensive simulation model and is shown to outperform state‐of‐the‐art solutions. Copyright © 2014 John Wiley & Sons, Ltd.
Sliding wear behaviors of Nomex fabric/phenolic composite under dry and water-bathed sliding conditions
Authors: Ren Guina , Zhang Zhaozhu , Zhu Xiaotao , Men Xuehu , Jiang Wei , Liu Weimin
Published: May 2014

A Nomex fabric/phenolic composite was prepared, and its tribological properties were evaluated under dry and water-bathed sliding conditions by a pin-on-disk tribometer. The resulting size of the friction coefficient for the Nomex fabric/phenolic composite in the study occurred in the following order: dry sliding condition > distilled water-bathed sliding condition > sea water-bathed sliding condition. The fabric composite’s wear rate from high to low was as follows: distilled water-bathed sliding condition > sea water-bathed sliding condition > dry sliding condition. Under water-bathed sliding conditions, penetration of water into the cracks accelerated the composite’s invalidation process, resulting in a higher wear rate. We also found that the extent of corrosion and transfer film formed on the counterpart pin significantly influenced the wear rate of the Nomex fabric composite. Discussion of the Nomex fabric composite’s wear mechanisms under the sliding conditions investigated is provided on the basis of the characterization results.
Covalent amphiphilic polyoxometalates for the design of biphasic microemulsion systems
Authors: Jallet V. , Guillemot G. , Lai J. , Bauduin P. , Nardello-Rataj V. , Proust A.
Published: May 2014

Unprecedented stabilization of a Winsor I microemulsion has been achieved using a covalent polyoxotungstate amphiphile.
Accounting for dye diffusion and orientation when relating FRET measurements to distances: three simple computational methods
Authors: Walczewska-Szewc Katarzyna , Corry Ben
Published: May 2014

A detailed analysis of three simple methods that account for dye diffusion and orientation when relating FRET measurements to distances.
In search of structure–function relationships in transition-metal based rectifiers
Authors: Weng Tingting , DeBrincat Daniel , Arcisauskaite Vaida , McGrady John E.
Published: May 2014

Using the paramagnetic moment of transition metal ions to tune the transparency of molecule–electrode heterojunctions holds the key to controlling current rectification.
Citrate modified ferrihydrite microstructures: facile synthesis, strong adsorption and excellent Fenton-like catalytic properties
Authors: Zhang Xuhong , Chen Yanzhuo , Zhao Ning , Liu Hui , Wei Yu
Published: May 2014

Flower-like citrate modified ferrihydrite microstructures, which exhibited good absorption ability and Fenton-like catalytic activity, were synthesized via a simple route.
Heavy atom tunneling in the automerization of pentalene and other antiaromatic systems
Authors: Kozuch Sebastian
Published: May 2014

Heavy atom tunneling? There is a light for anti-aromatic molecules!
l-(+)-Lactic acid production by co-fermentation of cellobiose and xylose without carbon catabolite repression using Enterococcus mundtii QU 25
Authors: Wang Ying , Abdel-Rahman Mohamed Ali , Tashiro Yukihiro , Xiao Yaotian , Zendo Takeshi , Sakai Kenji , Sonomoto Kenji
Published: May 2014

We established an effective highl-lactic acid production system based on fed-batch bacterial cultures utilising lignocellulosic biomass-derived mixed sugars without carbon catabolite repression.
Investigation of combinatorial coevaporated thin film Cu2ZnSnS4. I. Temperature effect, crystalline phases, morphology, and photoluminescence
Authors: Du Hui , Yan Fei , Young Matthew , To Bobby , Jiang Chun-Sheng , Dippo Pat , Kuciauskas Darius , Chi Zhenhuan , Lund Elizabeth A. , Hancock Chris , Hlaing OO Win Maw , Scarpulla Mike A. , Teeter Glenn
Published: May 2014

Cu2ZnSnS4 is a promising low-cost, nontoxic, earth-abundant absorber material for thin-film solar cell applications. In this study, combinatorial coevaporation was used to synthesize individual thin-film samples spanning a wide range of compositions at low (325 °C) and high (475 °C) temperatures. Film composition, grain morphology, crystalline-phase and photo-excitation information have been characterized by x-ray fluorescence, scanning electron microscopy, x-ray diffraction, Raman spectroscopy, and photoluminescence imaging and mapping. Highly textured columnar grain morphology is observed for film compositions along the ZnS-Cu2ZnSnS4-Cu2SnS3 tie line in the quasi-ternary Cu2S-ZnS-SnS2 phase system, and this effect is attributed to structural similarity between the Cu2ZnSnS4, Cu2SnS3, and ZnS crystalline phases. At 475 °C growth temperature, Sn-S phases cannot condense because of their high vapor pressures. As a result, regions that received excess Sn flux during growth produced compositions falling along the ZnS-Cu2ZnSnS4-Cu2SnS3 tie line. Room-temperature photoluminescence imaging reveals a strong correlation for these samples between film composition and photoluminescence intensity, where film regions with Cu/Sn ratios greater than ∼2 show strong photoluminescence intensity, in comparison with much weaker photoluminescence in regions that received excess Sn flux during growth or subsequent processing. The observed photoluminescence quenching in regions that received excess Sn flux is attributed to the effects of Sn-related native point defects in Cu2ZnSnS4 on non-radiative recombination processes. Implications for processing and performance of Cu2ZnSnS4 solar cells are discussed.
Temperature dependent Raman scattering studies of three dimensional topological insulators Bi2Se3
Authors: Irfan Bushra , Sahoo Satyaprakash , Gaur Anand P. S. , Ahmadi Majid , Guinel Maxime J.-F. , Katiyar Ram S. , Chatterjee Ratnamala
Published: May 2014

We investigate the temperature dependent (83 K≤T≤523 K) frequency shift of 2Ag1 and 1Eg2 phonon modes in the three dimensional topological insulator Bi2Se3, using Raman spectroscopy. The high quality single crystals of Bi2Se3 were grown using a modified Bridgman technique and characterized by Laue diffraction and high resolution transmission electron microscopy. A significant broadening in the line shape and red-shift in the frequencies were observed with increase in temperature. Polarized Raman scattering measurement shows a strong polarization effect of Ag1 and Ag2 phonon modes which confirms the good quality single crystals of Bi2Se3. Temperature co-efficient for A1g1, Eg2, and A1g2 modes was estimated to be −1.44 × 10−2, −1.94 × 10−2, and −1.95 × 10−2 cm−1∕K, respectively. Our results shed light on anharmonic properties of Bi2Se3.
Fragmentation of the adenine and guanine molecules induced by electron collisions
Authors: Minaev B. F. , Shafranyosh M. I. , Svida Yu. Yu , Sukhoviya M. I. , Shafranyosh I. I. , Baryshnikov G. V. , Minaeva V. A.
Published: May 2014

Secondary electron emission is the most important stage in the mechanism of radiation damage to DNA biopolymers induced by primary ionizing radiation. These secondary electrons ejected by the primary electron impacts can produce further ionizations, initiating an avalanche effect, leading to genome damage through the energy transfer from the primary objects to sensitive biomolecular targets, such as nitrogenous bases, saccharides, and other DNA and peptide components. In this work, the formation of positive and negative ions of purine bases of nucleic acids (adenine and guanine molecules) under the impact of slow electrons (from 0.1 till 200 eV) is studied by the crossed electron and molecular beams technique. The method used makes it possible to measure the molecular beam intensity and determine the total cross-sections for the formation of positive and negative ions of the studied molecules, their energy dependences, and absolute values. It is found that the maximum cross section for formation of the adenine and guanine positive ions is reached at about 90 eV energy of the electron beam and their absolute values are equal to 2.8 × 10−15 and 3.2 × 10−15 cm2, respectively. The total cross section for formation of the negative ions is 6.1 × 10−18 and 7.6 × 10−18 cm2 at the energy of 1.1 eV for adenine and guanine, respectively. The absolute cross-section values for the molecular ions are measured and the cross-sections of dissociative ionization are determined. Quantum chemical calculations are performed for the studied molecules, ions and fragments for interpretation of the crossed beams experiments.
Ionic size effects to molecular solvation energy and to ion current across a channel resulted from the nonuniform size-modified PNP equations
Authors: Qiao Yu , Tu Bin , Lu Benzhuo
Published: May 2014

Ionic finite size can impose considerable effects to both the equilibrium and non-equilibrium properties of a solvated molecular system, such as the solvation energy, ionic concentration, and transport in a channel. As discussed in our former work [B. Lu and Y. C. Zhou, Biophys. J. 100, 2475 (2011)], a class of size-modified Poisson-Boltzmann (PB)/Poisson-Nernst-Planck (PNP) models can be uniformly studied through the general nonuniform size-modified PNP (SMPNP) equations deduced from the extended free energy functional of Borukhov et al. [I. Borukhov, D. Andelman, and H. Orland, Phys. Rev. Lett. 79, 435 (1997)] This work focuses on the nonuniform size effects to molecular solvation energy and to ion current across a channel for real biomolecular systems. The main contributions are: (1) we prove that for solvation energy calculation with nonuniform size effects (through equilibrium SMPNP simulation), there exists a simplified approximation formulation which is the same as the widely used one in PB community. This approximate form avoids integration over the whole domain and makes energy calculations convenient. (2) Numerical calculations show that ionic size effects tend to negate the solvation effects, which indicates that a higher molecular solvation energy (lower absolute value) is to be predicted when ionic size effects are considered. For both calculations on a protein and a DNA fragment systems in a 0.5M 1:1 ionic solution, a difference about 10 kcal/mol in solvation energies is found between the PB and the SMPNP predictions. Moreover, it is observed that the solvation energy decreases as ionic strength increases, which behavior is similar as those predicted by the traditional PB equation (without size effect) and by the uniform size-modified Poisson-Boltzmann equation. (3) Nonequilibrium SMPNP simulations of ion permeation through a gramicidin A channel show that the ionic size effects lead to reduced ion current inside the channel compared with the results without considering size effects. As a component of the current, the drift term is the main contribution to the total current. The ionic size effects to the total current almost come through the drift term, and have little influence on the diffusion terms in SMPNP.
Homogenous nucleation rates of n-propanol measured in the Laminar Flow Diffusion Chamber at different total pressures
Authors: Görke Hanna , Neitola Kimmo , Hyvärinen Antti-Pekka , Lihavainen Heikki , Wölk Judith , Strey Reinhard , Brus David
Published: May 2014

Nucleation rates of n-propanol were investigated in the Laminar Flow Diffusion Chamber. Nucleation temperatures between 270 and 300 K and rates between 100 and 106 cm−3 s−1 were achieved. Since earlier measurements of n-butanol and n‑pentanol suggest a dependence of nucleation rates on carrier gas pressure, similar conditions were adjusted for these measurements. The obtained data fit well to results available from literature. A small positive pressure effect was found which strengthen the assumption that this effect is attributed to the carbon chain length of the n-alcohol [D. Brus, A. P. Hyvärinen, J. Wedekind, Y. Viisanen, M. Kulmala, V. Ždímal, J. Smolík, and H. Lihavainen, J. Chem. Phys. 128, 134312 (2008)] and might be less intensive for substances in the homologous series with higher equilibrium vapor pressure. A comparison with the theoretical approach by Wedekind et al. [Phys. Rev. Lett. 101, 12 (2008)] shows that the effect goes in the same direction but that the intensity is much stronger in experiments than in theory.
Development of a 33 kV, 20 A long pulse converter modulator for high average power klystron
Authors: Reghu T. , Mandloi V. , Shrivastava Purushottam
Published: May 2014

Research, design, and development of high average power, long pulse modulators for the proposed Indian Spallation Neutron Source are underway at Raja Ramanna Centre for Advanced Technology. With this objective, a prototype of long pulse modulator capable of delivering 33 kV, 20 A at 5 Hz repetition rate has been designed and developed. Three Insulated Gate Bipolar Transistors (IGBT) based switching modules driving high frequency, high voltage transformers have been used to generate high voltage output. The IGBT based switching modules are shifted in phase by 120° with respect to each other. The switching frequency is 25 kHz. Pulses of 1.6 ms pulse width, 80 μs rise time, and 70 μs fall time have been achieved at the modulator output. A droop of ±0.6% is achieved using a simple segmented digital droop correction technique. The total fault energy transferred to the load during fault has been measured by conducting wire burn tests and is found to be within 3.5 J.
Enhancement in field emission current density of Ni nanoparticles embedded in thin silica matrix by swift heavy ion irradiation
Authors: Sarker Debalaya , Kumar H. , Patra Rajkumar , Kabiraj D. , Avasthi D. K. , Vayalil Sarathlal K. , Roth S. V. , Srivastava P. , Ghosh S.
Published: May 2014

The field emission (FE) properties of nickel nanoparticles embedded in thin silica matrix irradiated with 100 MeV Au+7 ions at various fluences are studied here. A large increase in FE current density is observed in the irradiated films as compared to their as deposited counterpart. The dependence of FE properties on irradiation fluence is correlated with surface roughness, density of states of valence band and size distribution of nanoparticles as examined with atomic force microscope, X-ray photoelectron spectroscopy, and grazing incidence small angle x-ray scattering. A current density as high as 0.48 mA/cm2 at an applied field 15 V/μm has been found for the first time for planar field emitters in the film irradiated with fluence of 5.0 × 1013 ions/cm2. This significant enhancement in the current density is attributed to an optimized size distribution along with highest surface roughness of the same. This new member of field emission family meets most of the requirements of cold cathodes for vacuum micro/nanoelectronic devices.
Mechanically and optically controlled graphene valley filter
Authors: Qi Fenghua , Jin Guojun
Published: May 2014

We theoretically investigate the valley-dependent electronic transport through a graphene monolayer modulated simultaneously by a uniform uniaxial strain and linearly polarized light. Within the Floquet formalism, we calculate the transmission probabilities and conductances of the two valleys. It is found that valley polarization can appear only if the two modulations coexist. Under a proper stretching of the sample, the ratio of the light intensity and the light frequency squared is important. If this quantity is small, the electron transport is mainly contributed by the valley-symmetric central band and the conductance is valley unpolarized; but when this quantity is large, the valley-asymmetric sidebands also take part in the transport and the valley polarization of the conductance appears. Furthermore, the degree of the polarization can be tuned by the strain strength, light intensity, and light frequency. It is proposed that the detection of the valley polarization can be realized utilizing the valley beam splitting. Thus, a graphene monolayer can be used as a mechanically and optically controlled valley filter.
Mutual synchronization of two stacks of intrinsic Josephson junctions in cuprate superconductors
Authors: Lin Shi-Zeng
Published: May 2014

Certain high-Tc cuprate superconductors, which naturally realize a stack of Josephson junctions, thus can be used to generate electromagnetic waves in the terahertz region. A plate-like single crystal with 104 junctions without cavity resonance was proposed to achieve strong radiation. For this purpose, it is required to synchronize the Josephson plasma oscillation in all junctions. In this work, we propose to use two stacks of junctions shunted in parallel to achieve synchronization. The two stacks are mutually synchronized in the whole IV curve, and there is a phase shift between the plasma oscillation in the two stacks. The phase shift is nonzero when the number of junctions in different stacks is the same, while it can be arbitrary when the number of junctions is different. This phase shift can be tuned continuously by applying a magnetic field when all the junctions are connected by superconducting wires.
Assessing the spatial correlation and conduction state of breakdown spot patterns in Pt/HfO2/Pt structures using transient infrared thermography
Authors: Miranda E. , Riccio M. , De Falco G. , Blasco J. , Suñé J. , Irace A.
Published: May 2014

The generation and conduction state of breakdown spot patterns in HfO2-based metal-insulator-metal structures are investigated using transient infrared thermography in combination with spatial statistics. The spots are created at a low generation rate by applying an appropriate constant voltage stress to the devices. Because of the important thermal effects involved during degradation, the breakdown events leave their fingerprints on the top metal electrode in the form of two-dimensional point patterns. Contrary to what is expected, thermal mappings reveal that many of these failure sites do not longer conduct after their creation, which is consistent with a self-healing behavior. In order to investigate whether the local heat dissipation and thermal propagation induce spatial correlation among the failure events or not, the final breakdown spot spatial distributions are compared with simulations of homogeneous Poisson point processes in the plane and the results are validated against the smoothed residual field and quantile-quantile plots.