bluuebunny/crossref_metadata_2025 huggingface dataset:
Reductive amination with zinc powder in aqueous media
Authors: Giovenzana Giovanni B , Imperio Daniela , Penoni Andrea , Palmisano Giovanni
Published: August 2011

Zinc powder in aqueous alkaline media was employed to perform reductive amination of aldehydes with primary amines. The corresponding secondary amines were obtained in good yields along with minor amounts of hydrodimerization byproducts. The protocol is a green alternative to the use of complex hydrides in chlorinated or highly flammable solvents.
Collective Occupations among Filipina Migrant Workers: Bridging Disrupted Identities
Authors: Peralta-Catipon Terry
Published: August 2011

This article exemplifies how social and cultural contexts influenced identity-formation among individuals of a collectivistic community. Specifically, ethnographic data on Filipina workers in Hong Kong showed that disruptions caused by migration and foreign employment resulted in participants feeling conflicted about their sense of selves. Further, while still in the host country, participants' engagement in occupations with their peers also enabled the workers to embody new identities through recreation of familiar sociocultural contexts. Using the concept of “interdependent self construal,” the study shows how participants' identities shifted with changes in sociocultural contexts. Also, collective engagement in occupations proved instrumental in alleviating feelings of conflicted sense of selves. As such, this article may contribute to the body of knowledge about the interrelationships of occupation, culture, and identity-formation that, in turn, may enhance cultural competence among occupational therapy practitioners.
Revista Latina de Comunicación Social, en la red social Facebook
Authors: Herrero Gutiérrez Francisco Javier , Álvarez-Nobell Alejandro , López-Ornelas Maricela
Published: August 2011

Los nuevos espacios de ‘diálogo’ e interacción directa y bidireccional, promovidos por la incorporación de las herramientas de la Web 2.0, han impulsado y transformado los patrones tradicionales de la difusión científica así como el estudio de los modelos comunicacionales a la hora de vehicular este tipo de relaciones con la necesidad de identificar las características esenciales de sus usuarios. En este sentido, el presente trabajo aborda el objetivo de analizar la divulgación y vinculación académica que la Revista Latina de Comunicación Social (RLCS) ha generado desde su incorporación a principios de 2010 a las redes sociales de Facebook (como factor vital de este análisis) y Twitter. La metodología se asiste de técnicas mixtas que registran estadísticamente los datos obtenidos a través del programa Motigo Webstats así como del análisis generado a partir de la información proporcionada por sus usuarios. Entre los resultados se distingue un avance significativo por parte de RLCS en materia de difusión al compartir, mediante las redes sociales, las actualizaciones que realiza periódicamente, otorgándole un valor agregado a esta publicación electrónica al fortalecer su visibilidad a través del uso de las redes sociales.
An Empiric Analysis of Omaha System Targets
Authors: Melton-Meaux G. , Timm J. , Westra B. , Kerr M. , Raman N. , Farri O. , Hart C. , Martin K. , Monsen K.
Published: August 2011

Interface terminologies used in electronic health records must be re-evaluated and revised to reflect current health care practice and knowledge. To enable future revisions of the Omaha System Intervention Scheme, investigators evaluated formal semantic structure of target terms and concept duplication of problem and target terms. Using linguistic principles and qualitative analysis, five themes were found. A multidimensional formal semantic structure for the intervention target term was proposed. Concept duplication was examined for 16 problem-target matches. Clinical data enabled assessment of the validity of a proposed formal semantic structure and concept duplication. Recommendations are suggested for future development of the Omaha System Intervention Scheme.
Physician Quality and Health Care for the Poor and Uninsured
Authors: Gardner Lara , Vishwasrao Sharmila
Published: August 2011

Adverse health outcomes for uninsured patients have been attributed to their health status and to the quality of treatment received. A question about treatment that remains unexplored is whether physicians treating the uninsured are more likely to have characteristics indicative of lower quality than physicians treating insured patients. Using education, training, experience, and board certification to measure physician quality, we find that uninsured and Medicaid patients are treated by lower-quality physicians both because of the hospitals these patients attend and because of sorting within hospitals. The effects are statistically significant, but small.
The Impact of Ambulance Diversion on Heart Attack Deaths
Authors: Yankovic Natalia , Glied Sherry , Green Linda V. , Grams Morgan
Published: August 2011

Hospital ambulance diversions are prevalent and increasing nationwide as emergency departments experience growing congestion. Using negative binomial regressions, this paper links the number of acute myocardial infarction (AMI) deaths to the level and extent of diversion in the five boroughs of New York City. The results indicate that both high levels of ambulance diversion and simultaneous diversion across hospitals are associated with increasing numbers of deaths from AMI.
Health Care When Workers Need it Most: Before and after Entry into the Social Security Disability Insurance Program
Authors: Livermore Gina A. , Stapleton David C. , Claypool Henry
Published: August 2011

This study analyzed survey data on Social Security Disability Insurance (SSDI) beneficiaries during the six-year window surrounding SSDI entitlement to illustrate changes in characteristics, insurance status, and health care access. We found that SSDI beneficiaries were less likely to be insured than the general working-age population, even three years before SSDI entitlement, and their uninsurance rates remained high until the third year after SSDI entitlement. Health care access problems were reported frequently during all periods surrounding SSDI entitlement, and poverty rates increased markedly post-entitlement. The findings suggest that there are significant gaps in the safety net for disabled workers before, during, and after the transition to SSDI.
Rural and Urban Differences in Children's Medicaid and CHIP Participation
Authors: King Jennifer , Holmes George M. , Slifkin Rebecca T.
Published: August 2011

Efforts to increase enrollment in Medicaid and the Children's Health Insurance Program (CHIP) among uninsured children would benefit from an understanding of how program participation varies in rural and urban areas. Using Current Population Survey data from the period 2006–2007, rural participation rates were slightly higher than urban rates in the nation overall. There was no rural-urban difference when comparisons were based on within-state variation, independent of adjustment for individual characteristics. For researchers examining health policy issues strongly influenced by state policies or other state-level factors, this study highlights the challenges presented by national data sets with small or nonexistent samples from geographic areas within some states.
Reforming Beneficiary Cost Sharing to Improve Medicare Performance
Authors: Zuckerman Stephen , Shang Baoping , Waidmann Timothy
Published: August 2011

This paper explores options for reforming Medicare cost sharing in an effort to provide better financial protection for those beneficiaries with the greatest health care needs. Using data from the Health and Retirement Study (HRS) and the Medicare Current Beneficiary Survey (MCBS), we consider how unified annual deductibles, alternative coinsurance rates, and a limit on out-of-pocket spending would alter program spending, beneficiary cost sharing, and premiums for supplemental coverage. We show that adding an out-of-pocket limit and raising deductibles and coinsurance slightly would provide better safeguards to beneficiaries with high costs than the current Medicare benefit structure. Our estimates also suggest that policies protecting these beneficiaries could be structured in a way that would add little to overall program costs.
Gaseous pollutants in Beijing urban area during the heating period 2007–2008: variability, sources, meteorological, and chemical impacts
Authors: Lin W. , Xu X. , Ge B. , Liu X.
Published: August 2011

Abstract. Gaseous pollutants, NOy/NOx, SO2, CO, and O3, were measured at an urban site in Beijing from 17 November 2007 to 15 March 2008. The average concentrations (with ± 1σ) of NO, NO2, NOx, NOy, CO, SO2, and O3 were 29.0 ± 2.7 ppb, 33.7 ± 1.4 ppb, 62.7 ± 4.0 ppb, 72.8 ± 4.5 ppb, 1.99 ± 0.13 ppm, 31.9 ± 2.0 ppb, and 11.9 ± 0.8 ppb, respectively, with hourly maxima of 200.7 ppb, 113.5 ppb, 303.9 ppb, 323.2 ppb, 15.06 ppm, 147.3 ppb, and 69.7 ppb, respectively. The concentrations of the pollutants show "saw-toothed" patterns, which are attributable mainly to changes in wind direction and speed. The frequency distributions of the hourly mean concentrations of NOy, SO2, CO, and O3 can all be decomposed in the two Lorentz curves, with their peak concentrations representing background levels under different conditions. During the observation period, the average ratio NOx/NOy was 0.86 ± 0.10, suggesting that the gaseous pollutants in Beijing in winter are mainly from local emissions. Data of O3, NOz, and NOx/NOy indicate that photochemistry can take place in Beijing even in the cold winter period. Based on the measurements of O3, NOx, and NOy, ozone production efficiency (OPE) is estimated to be in the range of 0–8.9 (ppb ppb−1) with the mean(± 1σ) and median values being 1.1(± 1.6) and 0.5 (ppb ppb−1), respectively, for the winter 2007–2008 in Beijing. This low OPE would cause a photochemical O3 source of 5 ppb day−1, which is small but significant for surface O3 in winter in Beijing. Downward transport of O3-rich air from the free troposphere is the more important factor for the enhancement of the O3 level in the surface layer, while high NO level for the destruction of O3. The concentrations of SO2, CO, and NOx are strongly correlated among each other, indicating that they are emitted by some common sources. Multiple linear regression analysis is applied to the concentrations of NOy, SO2, and CO and empirical equations are obtained for the NOy concentration. Based the equations, the relative contributions from mobile and point sources to NOy is estimated to be 66 ± 30 % and 40 ± 16 %, respectively, suggesting that even in the heating period, mobile sources in Beijing contribute more to NOy than point sources.
Altered or Impaired Immune Response to Hepatitis B Vaccine in WNIN/GR-Ob Rat: An Obese Rat Model with Impaired Glucose Tolerance
Authors: Bandaru Prathibha , Rajkumar Hemalatha , Nappanveettil Giridharan
Published: August 2011

Obesity is shown to increase the incidence and severity of infectious diseases and individuals seem to exhibit poor antibody response to vaccination due to several inherent immune defects. With the increasing prevalence of impaired glucose tolerance (IGT) seen in obese individuals, the present study was aimed to investigate the basal immune response and immune response upon Hepatitis B vaccination (HBV) in an obese rat model WNIN/GR-Ob with impaired glucose tolerance (IGT). Decreased proportions of splenic CD4+T helper cells and CD3+T cells were observed in obese animals compared to lean animals. Upon HBV, obese animals showed reduced cell-mediated immunity and humoral immunity in terms of splenic lymphocyte proliferative response to Concanavalin A (Con A) and Hepatitis B surface antigen (HBsAg) and HBsAg-specific IgG response. Innate immunity as assessed in terms of Tumor Necrosis Factorα(TNFα) and Nitric oxide (NO) production by peritoneal macrophages upon HBV was low and unchanged, respectively, in obese animals. Thus long-term immunological memory is impaired or altered upon HBV.
Selective Oxidations of Organoboron Compounds Catalyzed by Baeyer–Villiger Monooxygenases
Authors: Brondani Patrícia B. , de Gonzalo Gonzalo , Fraaije Marco W. , Andrade Leandro H.
Published: August 2011

The applicability of Baeyer–Villiger monooxygenases (BVMOs) in organoboron chemistry has been explored through testing chemo‐ and enantioselective oxidations of a variety of boron‐containing aromatic and vinylic compounds. Several BVMOs, namely: phenylacetone monooxygenase (PAMO), M446G PAMO mutant, 4‐hydroxyacetophenone monooxygenase (HAPMO) and cyclohexanone monooxygenase (CHMO) were used in this study. The degree of chemoselectivity depends on the type of BVMO employed, in which the biocatalysts prefer boron‐carbon oxidation over Baeyer–Villiger oxidation or epoxidation. Interestingly, it was discovered that PAMO can be used to perform kinetic resolution of boron‐containing compounds with good enantioselectivities. These findings extend the known biocatalytic repertoire of BVMOs by showing a new family of compounds that can be oxidized by these enzymes.
Stereoselective Desymmetrization of 2,2‐Bishydroxymethyl‐1‐tetralones by Iodocyclization, Synthesis of Novel Enantiopure [6.6.5] Tricyclic Framework and Chemoenzymatic Diversity Generation
Authors: Mahapatra Tridib , Jana Navendu , Nanda Samik
Published: August 2011

Stereoselective halocyclization of pro‐chiral 2,2‐bishydroxymethyl‐1‐tetralone derivatives with N‐halosuccinamides afforded an interesting tricyclic scaffold found in many naturally occurring hasubanan alkaloids. Enantiopure tricyclic scaffolds are synthesized by using enzymatic kinetic resolution (EKR) of the parent racemic compound. Microbial ketoreductase (Geotrichum candidum, Aspergillus niger and Candida parapsilosis) mediated stereoselective reduction reactions have been successfully employed to these enantiopure tricyclic scaffolds which, followed by functional group manipulation, provides novel cyclic frameworks.
Construction of Trifluoromethyl‐Bearing Quaternary Carbon Centers by Intramolecular Decarboxylative Allylation of α‐Trifluoromethyl β‐Keto Esters
Authors: Shibata Norio , Suzuki Satoru , Furukawa Tatsuya , Kawai Hiroyuki , Tokunaga Etsuko , Yuan Zhe , Cahard Dominique
Published: August 2011

A new palladium‐catalyzed decarboxylative allylation of allyl α‐trifluoromethyl‐β‐keto esters was developed in the presence of tris(dibenzylideneacetone)dipalladium [Pd2(dba)3] and 1,2‐bis(diphenylphosphino)ethane (dppe) in tetrahydrofuran. α‐Trifluoromethyl ketones featuring a quaternary carbon center were produced in good yields and the dreaded α,β‐unsaturated‐β,β‐difluoro ketones resulting from β‐elimination of a fluoride ion was not observed.
Microdeletion at 4q21.3 is associated with intellectual disability, dysmorphic facies, hypotonia, and short stature
Authors: Dukes‐Rimsky Lynn , Guzauskas Gregory F. , Holden Kenton R. , Griggs Rachel , Ladd Sydney , del Carmen Montoya Maria , DuPont Barbara R. , Srivastava Anand K.
Published: August 2011

Chromosomal imbalances are a major cause of intellectual disability (ID) and multiple congenital anomalies. We have clinically and molecularly characterized two patients with chromosome translocations and ID. Using whole genome array CGH analysis, we identified a microdeletion involving 4q21.3, unrelated to the translocations in both patients. We confirmed the 4q21.3 microdeletions using fluorescence in situ hybridization and quantitative genomic PCR. The corresponding deletion boundaries in the patients were further mapped and compared to previously reported 4q21 deletions and the associated clinical features. We determined a common region of deletion overlap that appears unique to ID, short stature, hypotonia, and dysmorphic facial features. © 2011 Wiley‐Liss, Inc.
Whole‐exome sequencing identifies compound heterozygous mutations in WDR62 in siblings with recurrent polymicrogyria
Authors: Murdock David R. , Clark Gary D. , Bainbridge Matthew N. , Newsham Irene , Wu Yuan‐Qing , Muzny Donna M. , Cheung Sau Wai , Gibbs Richard A. , Ramocki Melissa B.
Published: August 2011

Polymicrogyria is a disorder of neuronal development resulting in structurally abnormal cerebral hemispheres characterized by over‐folding and abnormal lamination of the cerebral cortex. Polymicrogyria is frequently associated with severe neurologic deficits including intellectual disability, motor problems, and epilepsy. There are acquired and genetic causes of polymicrogyria, but most patients with a presumed genetic etiology lack a specific diagnosis. Here we report using whole‐exome sequencing to identify compound heterozygous mutations in the WD repeat domain 62 (WDR62) gene as the cause of recurrent polymicrogyria in a sibling pair. Sanger sequencing confirmed that the siblings both inherited 1‐bp (maternal allele) and 2‐bp (paternal allele) frameshift deletions, which predict premature truncation of WDR62, a protein that has a role in early cortical development. The probands are from a non‐consanguineous family of Northern European descent, suggesting that autosomal recessive PMG due to compound heterozygous mutation of WDR62 might be a relatively common cause of PMG in the population. Further studies to identify mutation frequency in the population are needed. © 2011 Wiley‐Liss, Inc.
Mild Tessier No. 7 cleft with PHACE syndrome: The case for pulmonary vascular steal
Authors: Bajaj Amit , Dyke Peter , Zaleski Christina , Cava Joseph , McPherson Elizabeth
Published: August 2011

We describe an unusual case of PHACE syndrome that provides a demonstration of the role of vascular anomalies in the causation of external ear and facial anomalies. The child in our case was characterized by a small segmental hemangioma of the face, tetralogy of Fallot, and anomalous origin of left common carotid artery from pulmonary artery with retrograde blood flow. This presumably resulted in hypoperfusion of the left side of the face resulting in a Tessier number 7 cleft and left ear anomaly explained by pulmonary vascular steal phenomenon. The absence of posterior fossa anomalies may reflect normal perfusion via the Circle of Willis. © 2011 Wiley‐Liss, Inc.
Physical health problems in adults with Prader–Willi syndrome
Authors: Sinnema Margje , Maaskant Marian A. , van Schrojenstein Lantman‐de Valk Henny M.J. , Caroline van Nieuwpoort I. , Drent Madeleine L. , Curfs Leopold M.G. , Schrander‐Stumpel Constance T.R.M.
Published: August 2011

Prader–Willi syndrome (PWS) is a genetic disorder which is characterized by severe hypotonia and feeding problems in early infancy. In later childhood and adolescence, this is followed by hyperphagia and extreme obesity if the diet is not strictly controlled. Data on physical health problems in adults with PWS are scarce. We report on the prevalence of physical health problems in a Dutch cohort of adults with PWS in relation to age, BMI, and genetic subtype. Participants (n = 102) were retrieved via the Dutch Prader–Willi Parent Association and through physicians specializing in persons with intellectual disabilities (ID). Details regarding physical health problem spanning the participants' lifespan were collected from caretakers through semi‐structured interviews. Cardiovascular problems included diabetes mellitus, hypertension, and cerebrovascular accidents. Respiratory infections were frequent in adulthood. In males, cryptorchidism was almost universal, for which 28/48 males had a history of surgery, mostly orchidopexy. None of the women had a regular menstrual cycle. Sixteen individuals had a diagnosis of osteoporosis. Spinal deformation, hip dysplasia, and foot abnormalities were common. Skinpicking, leg edema, and erysipelas were frequent dermatological problems. The findings in our group support the notion that the prevalence of physical health problems is underestimated. This underscores the importance of developing monitoring programs which would help to recognize physical health problems at an early stage. © 2011 Wiley‐Liss, Inc.
Modeling and stress–strain characteristics of the mechanical properties of carbon‐nanotube‐reinforced poly(vinyl acetate) nanocomposites
Authors: Merijs Meri Remo , Bitenieks Juris , Kalnins Martins , Maksimov Robert
Published: August 2011

Polymer/carbon nanotube (CNT) composites are one of the most perspective advanced materials developed in recent years. The properties of CNT‐reinforced polymer composites, however, strongly depend on structural aspects of the nanostructured filler and on its dispersion quality in a polymer matrix. Consequently, this research was devoted to the investigation of multiwalled‐CNT‐modified poly(vinyl acetate) (PVAc) composites with respect to the mechanical property dependence on some structural characteristics of CNTs. PVAc/CNT nanocomposites were obtained with a solution casting technique. The amount of CNTs was changed from 0.01 up to 2 wt %. The stress–strain characteristics of PVAc/CNT nanocomposites clearly revealed remarkable reinforcing effects of the CNT additions already at 0.01 wt %. At this CNT concentration, the elastic modulus (E) and tensile yield stress increased by 12.5 and 60%, respectively. Special attention was paid to the change of E with respect to some structural characteristics of CNTs. A corresponding mathematical model for the prediction of the elastic properties of CNT polymer nanocomposites is proposed, showing that elastic constants of the nanocomposites largely depend on the agglomeration of CNTs. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Influence of the stacking sequence on the porosity in carbon fiber composites
Authors: Toscano C. , Vitiello C.
Published: August 2011

Several composite laminate structures with different stacking sequences were manufactured to study how the special orientation of the fibers can influence the porosity distribution in the material. Different amounts of porosity were introduced into the laminate during autoclave curing through the application of pressures that differed from the prescribed one. All of the obtained structures were analyzed by ultrasonic inspection to measure the attenuation undergone by the signal through crossing within the material. Subsequently, the attenuation variations were associated with the induced porosity. The obtained results were corroborated by an estimation of the percentage of porosity introduced into the composites structures through the application of a standard method for density measurement. The results prove that there are stacking sequences much more subject to trap air with the consequent formation of the porosity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Poly(vinyl chloride)/CaCO3 nanocomposites: Influence of surface treatments on the properties
Authors: Bonadies Irene , Avella Maurizio , Avolio Roberto , Carfagna Cosimo , Errico Maria Emanuela , Gentile Gennaro
Published: August 2011

Poly(vinyl chloride) (PVC)‐based nanocomposites containing calcium carbonate nanoparticles (CaCO3) were prepared. Different nanoparticle surface modifiers were selected and tested to promote matrix/filler interactions and, consequently, to obtain high‐ performance materials. In particular, the nanoparticles were modified with poly(acrylic acid) (PAA) and poly (butadiene‐co‐acrylonitrile‐co‐acrylic acid) (PBAA). For comparison, PVC‐based materials, with the addition of commercial neat and stearic acid modified CaCO3, were also prepared. The influence of CaCO3 and surface modifiers on the gelation, thermal properties, thermal stability, and mechanical properties of PVC was studied. The gelation time of the rigid PVC/CaCO3 composites decreased as a function of the percentage and surface treatment of CaCO3. Morphological analysis proved the effectiveness of PAA and PBAA as surface modifiers; they obtained for the corresponding materials a typical nanostructured morphology. A significant improvement in the PVC thermal stability was recorded with the addition of neat and stearic acid modified CaCO3. Finally, mechanical tests showed an increase in the flexural strength and toughness of PVC as a function of the nanoparticle surface modifier. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Interleukin‐17A induction of angiogenesis, cell migration, and cytoskeletal rearrangement
Authors: Moran Ellen M. , Connolly Mary , Gao Wei , McCormick Jennifer , Fearon Ursula , Veale Douglas J.
Published: August 2011

Objective

To examine the ability of interleukin‐17A (IL‐17A) to stimulate angiogenesis, cell migration, and cytoskeletal rearrangement.

Methods

The effect of IL‐17A on microvascular tube formation and extracellular matrix invasion by human dermal endothelial cells (HDECs) was assessed using Matrigel matrix and Transwell Matrigel invasion chambers. IL‐17A–induced growth‐related oncogene α (GROα) and monocyte chemotactic protein 1 (MCP‐1) production in rheumatoid arthritis synovial fibroblasts (RASFs) and HDECs was measured by enzyme‐linked immunosorbent assay. IL‐17A–induced migration was assessed using peripheral blood mononuclear cell (PBMC) migration assays and wound‐repair scratch assays, with or without anti‐GROα and anti–MCP‐1 antibodies. Binding of β1 integrin receptors was assessed using integrin binding assays. Cytoskeletal assembly/disassembly in RASFs and HDECs were assessed by immunofluorescence staining for F‐actin. IL‐17A–induced cell migration and cytoskeletal disassembly were assessed in the presence of a Rac1 inhibitor (NSC23766). Rac1 activation following IL‐17 stimulation in the presence or absence of anti‐GROα, anti–MCP‐1, or IgG control was assessed by Rac GTPase pull‐down assays and Western blotting.

Results

IL‐17A significantly up‐regulated angiogenesis and endothelial cell invasion. It significantly induced GROα and MCP‐1 expression in RASFs. Migration of PBMCs, RASFs, and HDECs was induced by IL‐17A; these effects were blocked by anti‐GROα or anti–MCP‐1 antibodies. IL‐17A significantly up‐regulated β1 integrin receptor binding and induced cytoskeletal disassembly in RASFs and HDECs. Rac1 activation was directly induced by IL‐17A. IL‐17A–induced wound repair and actin rearrangement were inhibited by a pharmacologic inhibitor of Rac1 (NSC23766). Anti‐GROα or anti–MCP‐1 antibodies had no effect on IL‐17A–induced Rac1 activation.

Conclusion

IL‐17A induces angiogenesis, cell migration, and cell invasion, all of which are key processes in the pathogenesis of rheumatoid arthritis and ones that are mediated in part through chemokine‐ and cytoskeleton‐dependent pathways.
Antibacterial Agents and Cystic Fibrosis: Synthesis and Antimicrobial Evaluation of a Series of N‐Thiomethylazetidinones
Authors: Galletti Paola , Cocuzza Clementina E. A. , Pori Matteo , Quintavalla Arianna , Musumeci Rosario , Giacomini Daria
Published: August 2011

The increasing emergence of multidrug‐resistant microorganisms is one of the greatest challenges in the clinical management of infectious disease. New antimicrobial agents are therefore urgently required, particularly in the treatment of chronic and recurrent infections often associated with antibiotic‐resistant pathogens, as in the case of cystic fibrosis (CF) patients. This study reports the antibacterial activity of a series of monocyclic β‐lactams with an alkylidenecarboxyl chain or electron‐withdrawing groups such as 4‐OAc, 4‐SAc, and 4‐SO2Ph at the C4 position of the ring. N‐Unsubstituted and N‐thiomethyl derivatives were compared. A total of 33 azetidinones were tested for their activity against Gram‐positive and Gram‐negative bacterial clinical isolates. The combination of an N‐thiomethyl group and a benzyl ester on the 4‐alkylidene side chain were found to increase the potency against Gram‐positive bacteria. The N‐thiomethyl group clearly elevated the activity of 4‐acetoxyazetidinones relative to the corresponding NH derivatives. The most active compounds showed minimum inhibitory concentration (MIC) values of 4 and 8 mg L−1 against methicillin‐resistant Staphylococcus aureus isolated from pediatric patients with CF.
Casting a net on dendritic spines: The extracellular matrix and its receptors
Authors: Dansie Lorraine E. , Ethell Iryna M.
Published: August 2011

Dendritic spines are dynamic structures that accommodate the majority of excitatory synapses in the brain and are influenced by extracellular signals from presynaptic neurons, glial cells, and the extracellular matrix (ECM). The ECM surrounds dendritic spines and extends into the synaptic cleft, maintaining synapse integrity as well as mediating trans‐synaptic communications between neurons. Several scaffolding proteins and glycans that compose the ECM form a lattice‐like network, which serves as an attractive ground for various secreted glycoproteins, lectins, growth factors, and enzymes. ECM components can control dendritic spines through the interactions with their specific receptors or by influencing the functions of other synaptic proteins. In this review, we focus on ECM components and their receptors that regulate dendritic spine development and plasticity in the normal and diseased brain. © 2011 Wiley Periodicals, Inc. Develop Neurobiol 71: 956‐981, 2011
Motoneuron programmed cell death in response to proBDNF
Authors: Taylor Anna R. , Gifondorwa David J. , Robinson Mac B. , Strupe Jane L. , Prevette David , Johnson James E. , Hempstead Barbara , Oppenheim Ronald W. , Milligan Carolanne E.
Published: August 2011

Motoneurons (MN) as well as most neuronal populations undergo a temporally and spatially specific period of programmed cell death (PCD). Several factors have been considered to regulate the survival of MNs during this period, including availability of muscle‐derived trophic support and activity. The possibility that target‐derived factors may also negatively regulate MN survival has been considered, but not pursued. Neurotrophin precursors, through their interaction with p75NTR and sortilin receptors have been shown to induce cell death during development and following injury in the CNS. In this study, we find that muscle cells produce and secrete proBDNF. ProBDNF through its interaction with p75NTR and sortilin, promotes a caspase‐dependent death of MNs in culture. We also provide data to suggest that proBDNF regulates MN PCD during development in vivo. © 2011 Wiley Periodicals, Inc. Develop Neurobiol 72: 699–712, 2012
Macroscale evolutionary patterns of flight muscle dimorphism in the carrion beetle Necrophila japonica
Authors: Ikeda Hiroshi , Sota Teiji
Published: August 2011

Some insect species exhibit polymorphisms in flight muscles or wings, which provide opportunities for studying the factors that drive dispersal polymorphisms and the evolution of flightlessness in insects. We investigated the macroscale evolutionary pattern of flightlessness in the widespread Japanese beetle Necrophila japonica (Coleoptera: Silphidae), which exhibits flight muscle dimorphisms using phylogeographic approaches. N. japonica lives in both stable and unstable habitats, and the flight muscle dimorphisms may have been maintained through the use of these diverse habitats. We studied the distribution pattern of the proportion of individuals lacking flight muscles in relation to the genetic differentiation among geographic populations using an 842‐base pair sequence of the COI‐II gene. Both flight‐capable and flightless individuals occurred over the distribution area, and the flight muscle condition showed no significant phylogeographic pattern. Several populations comprised flight‐capable individuals only, whereas few comprised flightless ones only. Demographic expansion was suggested for major clades of COI‐II haplotypes, and the genetic differentiation showed an isolation‐by‐distance pattern among the populations in Japan. The proportion of flightless individuals was higher in a population with a higher annual mean temperature and with higher genetic diversity among individuals. These results indicate that geographic expansion occurred recently while flight muscle dimorphisms have been maintained, that flight‐capable individuals have colonized cooler (peripheral) habitats, and that flightlessness has increased in long‐persisting populations as suggested by high genetic diversity.
Synthesis and Thermal Stability Studies of CaFe4As3
Authors: Yi Tanghong , Dioguardi Adam P. , Klavins Peter , Curro Nicholas J. , Zhao Liang L. , Morosan E. , Kauzlarich Susan M.
Published: August 2011

CaFe4As3 is a new intermetallic structure type that can be described as a framework comprising of FeAs4 tetrahedra. The structure has similarities to the 1‐2‐2 superconducting phase in that the Fe/As network is related to the ThCr2Si2 structure. In addition, this phase shows magnetic transitions associated with spin density waves. This phase was prepared from a Sn flux, and it has recently been reported that further expansion of this structure type via chemical substitution is limited. We have developed a solid‐state synthesis route for the preparation of CaFe4As3 that involves reacting a stoichiometric combination of the constituent elements. The thermal stability of this material was investigated over the 298–1473 K temperature range. An initial investigation of the Sn grown CaFe4As3 crystals showed that residual Sn that was present on the surface of the crystals reacted with the crystals at temperatures above 1173 K to form new phases. A thermal stability study of Sn‐free CaFe4As3 indicated that it decomposed to give CaFe2As2 and Fe2As. The thermal behavior of CaFe2As2 was also investigated and the data showed that it can also form CaFe4As3 at high temperatures. The solid‐state synthesis route presented herein and additional solid solution studies may provide opportunities for the prepartion of materials with this structure type with improved electronic properties.
α‐/β‐Formylated Boron–Dipyrrin (BODIPY) Dyes: Regioselective Syntheses and Photophysical Properties
Authors: Yu Changjiang , Jiao Lijuan , Yin Hao , Zhou Jinyuan , Pang Weidong , Wu Yangchun , Wang Zhaoyun , Yang Gaosheng , Hao Erhong
Published: August 2011

Formylation has been performed on pyrrole‐unsubstituted dipyrromethanes 1 and boron–dipyrrin (BODIPY) dyes 4 based on a Vilsmeier–Haack reaction. It is highly regioselective and complementary and occurs exclusively at the α‐ and β‐position, respectively, for pyrrole‐unsubstituted dipyrromethanes 1 and BODIPY dyes 4. This regioselective formylation enables the syntheses of a variety of α‐ and β‐substituted BODIPY dyes. The installation of formyl groups affects the electronic properties of the BODIPY chromophore, resulting in red‐ and blueshifts of the absorption and emission maxima, respectively, for the α‐ and β‐formylatedBODIPYs 3 and 5.
Therapeutic plasma exchange and renal related vasculitis: Therapeutic apheresis academy 2010
Authors: Balogun Rasheed A. , Abdel‐Rahman Emaad M.
Published: August 2011

Therapeutic plasma exchange (TPE), a form of extracorporeal therapy, has been used in the management of many systemic conditions some of which include the systemic vasculitides that affect the kidneys. The following is a mini review of what is known about renal related indications for TPE in such conditions and the evidence based literature available as presented at the Therapeutic Apheresis Academy in September 2010. J. Clin. Apheresis, 2011. © 2011 Wiley‐Liss, Inc.
Biochemical, sensory and microbiological attributes of bream (Megalobrama amblycephala) during partial freezing and chilled storage
Authors: Song Yongling , Luo Yongkang , You Juan , Shen Huixing , Hu Sumei
Published: August 2011

BACKGROUND: Bream is one of the main farmed freshwater fish species in China. This study aimed to examine the nucleotide degradation of bream during partial freezing and chilled storage and to assess the possible usefulness of nucleotide ratios (K, Ki, H, P, Fr and G values) as freshness indices in comparison with sensory assessment and total viable counts.

RESULTS: Total viable counts were 5.74 and 4.66 log(colony‐forming units g−1) on the day of sensory rejection under chilled storage and partial freezing storage respectively. The inosine 5‐monophosphate decrease and inosine increase were faster in chilled storage than in partial freezing storage. Hypoxanthine levels increased continuously with time under both storage regimes. Among the nucleotide ratios, the K, Ki, P, G and Fr values were superior to the H value and provided useful freshness indicators for both storage conditions.

CONCLUSION: Bream in chilled storage were sensorially acceptable only up to 10 days, compared with 33 days for bream in partial freezing storage. Partial freezing delayed the nucleotide degradation of bream. Copyright © 2011 Society of Chemical Industry
Studies on highly conducting Polypyrrole/Fe3O4 nanocomposites
Authors: Mathad Jyotsna Kiran , Rao R.M.V.G.K.
Published: August 2011

Polypyrrole (PPy)/Fe3O4 nanocomposites were in situ synthesized using chemical oxidative polymerization in an aqueous solution of FeCl3.6H2O, in presence of different Fe3O4 loadings (0%–16.52%). These composites were characterized through a 4 Probe electrical conductivity measurement technique, Fourier Transform infrared spectroscopy, energy dispersive X‐ray spectroscopy, scanning electron microscopy, X‐ray diffraction, thermo gravimetric analysis, and vibrating sample magnetometer. Results showed maximum electrical conductivity of 75.28 S/cm for the 2.52% Fe3O4 loaded nanocomposite and with improved thermal stability compared with the host PPy. Furthermore, a linear relationship between saturated magnetization Ms and % composition of Fe3O4 in the above nanocomposites was observed, showing 6.34 emu/g at 16.52% Fe3O4/PPy nanocomposite. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers
Preparation and characterization of graphene composites with conducting polymers
Authors: Trang Le Kim Huyen , Thanh Tung Tran , Young Kim Tae , Yang Woo Seok , Kim Hyeongkeun , Suh Kwang S
Published: August 2011

We report a new route for preparing electro‐conductive composites based on reduced graphene oxide (RG‐O) and poly(3,4‐ethylenedioxythiophene) (PEDOT). The composites were prepared by in situ polymerization of EDOT in aqueous mixture containing RG‐O platelets modified with poly(sodium 4‐styrenesulfonate) (PSS). In the synthetic process, PSS molecules stabilize RG‐O in the aqueous phase and function as a polymerization template to hybridize PEDOT chains along RG‐O platelets. Compared with the RG‐O platelets, the resulting composites show an enhanced electrical conductivity of 9.2 S cm−1 with good thermal stability. Copyright © 2011 Society of Chemical Industry
Single fatherhood due to cancer
Authors: Yopp Justin M. , Rosenstein Donald L.
Published: August 2011

Cancer is a leading cause of widowed fatherhood in the USA. Fathers whose spouses have died from cancer constitute a potentially vulnerable population as they adjust to their role as sole or primary caregiver while managing their own grief and that of their children. The importance of addressing the psychological needs of widowed fathers is underscored by data showing that father's coping and emotional availability are closely tied to their bereaved children's mental health. Surprisingly, scant attention has been given to the phenomenon of widowed fatherhood with virtually no clinical resources or research studies devoted to fathers who have lost their wives to cancer. This commentary highlights key challenges facing this underserved population of widowers and calls for development of research agendas and clinical interventions for single fathers due to cancer. Copyright © 2011 John Wiley & Sons, Ltd.
Heterogeneous solvothermal synthesis of one‐dimensional titania nanostructures on transparent conductive glasses
Authors: Jia Qiaoying , Que Wenxiu , Zhang Jin
Published: August 2011

The present study reports a novel method for a direct growth of one‐dimensional (1D) TiO2 nanoarchitectures on fluorine‐doped tin oxide (FTO) conductive glass by a heterogeneous solvothermal route. Results indicate that the morphologies of the obtained samples can be controlled and changed from vertically oriented single‐crystalline rutile nanowire arrays to randomly disoriented nanotubular architectures by controlling the position of the substrate and the amount of the initial precursor. At a low concentration of the precursor, dandelion‐like TiO2 comprised of large amounts of the crystalline nanorods are found on the nonconductive surface of the horizontally oriented FTO glass, which are suitable for photocatalysis, while TiO2 nanowire arrays are grown on the conductive surface of the FTO glass, which can be used as photoanodes for sensitized solar cells to enhance the electron‐transport rate. The difference in morphology is probably related to the selective adsorption of the Cl ions, the texture of the substrate, and the immiscibility between the nonpolar solvent and the aqueous solution.
A green and fast way for reduction of graphene oxide in acidic aqueous solution via microwave assistance
Authors: Lu Ting , Pan Likun , Nie Chunyang , Zhao Zhiwei , Sun Zhuo
Published: August 2011

A facile and pollution‐free method was applied to prepare graphene nanosheets by reducing graphene oxide in acidic aqueous solution without any toxic chemicals via microwave heating. The surface morphology, structure, and composition characterizations were carried out using atomic force microscopy, field‐emission scanning electron microscopy, transmission electron microscopy, energy‐dispersive X‐ray spectroscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy, respectively. The results showed that high‐quality and large‐area reduced graphene nanosheets were obtained.
Coherent quantum transport in ferromagnet/s±‐wave superconductor/ferromagnet structures
Authors: Zhao X. L. , Tao Y. C.
Published: August 2011

We extend the Blonder–Tinkham–Klapwijk approach to studying the effects of barrier strength and spin polarization on coherent spin‐polarized transport in ferromagnet (FM)/iron‐pnictide‐superconductor (SC)/FM structures with s±‐paring for the SC. It is demonstrated that the effects of barrier strength and spin polarization on the particular features of oscillations of all the reflection and transmission probabilities, and differential conductances with energy in ferromagnetic and antiferromagnetic alignments of the magnetizations of the two FMs are different, which are also different from those for the s++ model.
Effects of thermal treatment on structure and magnetic properties of nonstoichiometric perovskite‐type oxides La0.67Sr0.15□0.18MnO3‐δ
Authors: Ge J. J. , Yang M. , Xue X. B. , Du J. , Wu X. S. , Tan W. S.
Published: August 2011

The structural and magnetic properties of La0.67Sr0.15□0.18MnO3‐δ manganites obtained with various thermal treatment conditions have been studied. X‐ray diffraction studies show that all the samples crystallize with the rhombohedral symmetry and the space group is R‐3c. No change in structural symmetry is found for all samples with thermal treatment. However, the bond angles of MnOMn and O1MnO2 deviate from 180 and 90 °, respectively, indicating the presence of Jahn–Teller type distortion in the MnO6 octahedron. And the oxygen content shows determinant affect on compound magnetic properties. With increasing oxygen content induced by thermal treatments, the Curie temperatures TC increases systematically from ∼280 to ∼303 K, showing the dependence of sample magnetic properties on sintering processes. A maximum value of |ΔSM(T, H)| is measured to be more than 5 J/kg · K near the curie temperature, indicating the potential of utilizing the strong magnetocaloric effect of these materials in magnetic refrigeration.
Tuning the exchange bias training effect in top‐ and bottom‐pinning FeNi/FeMn bilayers
Authors: Yang M. , Ge J. J. , Xue X. B. , Yang Y. , Rui W. B. , You B. , Sun L. , Du J. , Hu A.
Published: August 2011

A magnetic field of 600 Oe, different from the original pinning direction (PD), is applied in the film plane to tune the exchange bias (EB) training effect in both top‐ and bottom‐pinning FeNi/FeMn bilayers. Compared to the top‐pinning structures, the training effects in the bottom‐pinning ones are more easily tuned, characterized by larger rotation of the PD just after the field tuning. The EB tuning effect is thought to be originated from spin frustration near the FM/AF interface, and the interfacial AF spins are less stable and readily to be tuned by external field in the bottom‐pinning bilayers than those in the top‐pinning bilayers. This statement can also be validated by the azimuthal dependence of the EB effect.
Mechanical fabrication of carbon nanotube/TiO2 nanoparticle composite films and their field‐emission properties
Authors: He Kai‐Xuan , Su Juan , Guo Deng‐Zhu , Xing Ying‐Jie , Zhang Geng‐Min
Published: August 2011

A simple mechanical rubbing method for fabricating films of carbon nanotubes (CNTs) and CNTs‐based composite materials is presented, and films of CNTs, TiO2 nanoparticles, and CNTs‐TiO2 composite with different proportions are realized. The field emission (FE) properties of these films are systematically studied in comparison experiments. It is found that the TiO2 films show neglectable FE current in the electrical field up to 10 V/µm, and CNTs‐TiO2 composite films with an optimum proportion (7–10 wt.%) of TiO2 nanoparticles exhibit dramatically‐improved FE properties compared with pure CNT films, in lowering turn‐on filed to 1.3 V/µm (CNT films: 2.5 V/µm), suppressing the degradation of FE current, and increasing the FE uniformity and stability. The mechanisms responsible for such improvement are also discussed.
Resonant multimeander‐metasurfaces: A model system for superlenses and communication devices
Authors: Schweizer H. , Fu L. , Hentschel M. , Weiss T. , Bauer C. , Schau P. , Frenner K. , Osten W. , Giessen H.
Published: August 2011

We study the optical properties of single and double meander meta surfaces (MMS). A strong and resonant photon–plasmon coupling in single and double structures is found. The effect can be used to mimic bulk negative index materials with a promise for lower optical losses. Based on the optical properties of the MMS structures the application fields reach from near/far field lenses to communication devices. The strong photon–plasmon coupling effects pave the route for dense optical/plasmonic integration.
Towards description of kinetics of dissolution and cluster growth in C60/NMP solutions
Authors: Tropin T. V. , Avdeev M. V. , Kyzyma O. A. , Yeremin R. A. , Jargalan N. , Korobov M. V. , Aksenov V. L.
Published: August 2011

Model growth of fullerene C60 clusters in the solution in N‐methyl‐2‐pyrrolidone (NMP) is considered in the frame of nucleation theory. In addition to the previous models, the reason for the supersaturation caused the cluster formation is related to the appearance of new C60–NMP complexes with NMP. The dissolution process is taken into account. Different regimes of the proposed models depending on the kinetic parameters are distinguished and analyzed.
Photoluminescence evaluation of the quality of Cd0.9Zn0.1Te detectors doped with different indium concentrations
Authors: Naseka Yu. , Strilchuk O. , Komar V. , Terzin I. , Sulima S. , Bryleva K.
Published: August 2011

With the aim to determine an optimal indium (In) concentration in Cd0.9Zn0.1Te:In nuclear radiation detectors for a good material quality, low‐temperature photoluminescence (LTPL) measurements have been performed at 5 K in the energy range of 1.2–1.7 eV. The LTPL spectrum of initial sample contained a neutral acceptor bound exciton (A0X) peak at 1.635 eV, donor–acceptor pair (DAP) peak at 1.606 eV with its 1LO phonon replica, and deep‐level defects (D) peak at 1.455 eV. In doping leads to the appearance of a new relatively intensive peak at 1.652 eV that is caused by a shallow neutral donor bound exciton (D0X) due to In substituting cadmium vacancies (VCd). At In concentrations of about 8 × 1016–1017 cm−3 the value of $I_{{\rm D}^{{\rm 0}} {\rm X}} /I_{{\rm D}} $ ratio is maximal, which indicates a low density of detrimental carrier traps and, therefore, high‐material quality. We believe that at such concentrations the majority of as‐grown Cd vacancies will be substituted by In atoms and, therefore, noted concentrations are optimal, which was confirmed by the correlation with mobility–lifetime product.