bluuebunny/crossref_metadata_2025 huggingface dataset:
Theoretical investigation of a water‐gas‐shift catalytic membrane for diesel reformate purification
Authors: Kuncharam Bhanu Vardhan Reddy , Wilhite Benjamin A.
Published: July 2013

The novel application of a catalytic water‐gas‐shift membrane reactor for selective removal of CO from H2‐rich reformate mixtures for achieving gas purification solely via manipulation of reaction and diffusion phenomena, assuming Knudsen diffusion regime and the absence of hydrogen permselective materials, is described. An isothermal, two‐dimensional model is developed to describe a tube‐and‐shell membrane reactor supplied with a typical reformate mixture (9% CO, 3% CO2, 28% H2, and 15% H2O) to the retentate volume and steam supplied to the permeate volume such that the overall H2O:CO ratio within the system is 9:1. Simulations indicate that apparent CO:H2 selectivities of 90:1 to >200:1 at H2 recoveries of 20% to upwards of 40% may be achieved through appropriate design of the catalytic membrane and selection of operating conditions. Under these conditions, simulations predict an apparent hydrogen permeability of 2.3 × 10−10 mol m−1 Pa, which compares favorably against that of competing hydrogen‐permselective membranes. © 2013 American Institute of Chemical Engineers AIChE J, 59: 4334–4345, 2013
Analysis of differentially expressed proteins in late‐stationary growth phase of Mycobacterium tuberculosisH37Rv
Authors: Ang Kai‐Cheen , Ibrahim Pazilah , Gam Lay‐Harn
Published: July 2013

Mycobacterium tuberculosis is a causative agent of tuberculosis (TB). The ability of M. tuberculosis to be quiescent in the cell has caused the emergence of latent infection. A comprehensive proteomic analysis of M. tuberculosis H37Rv over three growth phases, namely mid‐log (14‐day culture), early stationary (28‐day culture), and late stationary (50‐day culture), was performed in order to study the change in proteome from the mid‐log phase to late‐stationary phase. Combination methods of two‐dimensional electrophoresis (2‐DE) and tandem mass spectrometry were used to generate proteome maps of M. tuberculosis at different growth phases. Ten proteins were detected differentially expressed in the late‐stationary phase compared with the other two phases. These proteins were SucD, TrpD, and Rv2161c, which belong to metabolic pathway proteins; FadE5, AccD5, DesA1, and Rv1139c are proteins involved in cell wall or lipid biosynthesis, whereas TB21.7 and Rv3224 are conserved hypothetical proteins with unknown function. A surface antigen protein, DesA1, was not detectable in the late‐stationary phase, although present in both log and early‐stationary phases. The changes in the expression levels of these proteins were in line with the growth environment changes of the bacteria from mid‐log phase to late‐stationary phase. The information gathered may be valuable in the intervention against latent TB infection.
Strategies for Developing an Environmentally Sustainable Supply Chain: Differences Between Manufacturing and Service Sectors
Authors: Chiarini Andrea
Published: July 2013

This research illuminates the debate on whether there are differences between the manufacturing and service sectors in the matter of developing a sustainable environmental supply chain. Over the past 5 years a survey has been conducted with 800 large European companies, of which half are in the manufacturing sector and half in the service sector. The hypotheses within the survey are related to strategies for developing an environmental supply chain. They were derived from a literature review and were tested by means of a chi‐square test. The survey questionnaire enabled the respondents to give some viewpoints about the hypotheses. In this way, strategies for developing the supply chain such as ISO 14001, the Eco‐Management and Audit Scheme (EMAS), Life Cycle Assessment (LCA), auditing, waste management systems, reverse logistics, environmental indicators, remanufacturing and reuse have been investigated. Results show interesting and unexpected differences between manufacturing and service sectors that can lead to further research, practical implications and even suggestions for the surveyed companies. For instance, the viewpoints of manufacturing and service industries differ over ISO 14001 and EMAS implementation in the supply chain. In addition, service industries approach the implementation of auditing, reverse logistics, reuse and remanufacturing in a way different from that of manufacturing. Other strategies are considered essential by both sectors. Copyright © 2013 John Wiley & Sons, Ltd and ERP Environment.
ChemInform Abstract: Chemical and Microbial Remediation of Hexavalent Chromium from Contaminated Soil and Mining/Metallurgical Solid Waste: A Review
Authors: Dhal B. , Thatoi H. N. , Das N. N. , Pandey B. D.
Published: July 2013

Review: 231 refs.
Synthesis and Complexation Properties of “Unsymmetrical” Sucrose‐Based Receptors
Authors: Potopnyk Mykhaylo A. , Jarosz Sławomir
Published: July 2013

New “unsymmetrical”, sucrose‐based diaza‐crown ethers have been designed and prepared from monosilylated hexa‐O‐benzylsucrose derivatives. The enantioselective complexation of phenylethylammonium cations by these receptors was evaluated. It was demonstrated that the introduction of the amino group at the 6‐position (glucose moiety) in sucrose increases the association constant for the S cation, but reduces the enantioselectivity. On the other hand, introduction of the amino group at the 6′‐position (fructose moiety) in sucrose increases significantly the value of Ka and at the same time the high enantioselectivity is preserved.
Aryne Cycloaddition Reactions in the Synthesis of Large Polycyclic Aromatic Compounds
Authors: Pérez Dolores , Peña Diego , Guitián Enrique
Published: July 2013

Cycloaddition reactions involving arynes provide privileged strategies for the convergent synthesis of polycyclic compounds containing aromatic rings. This review focuses on the application of aryne chemistry, in particular [4+2] and palladium‐catalysed [2+2+2] cycloaddition reactions, in the synthesis of large polycyclic aromatic hydrocarbons (PAHs) containing five or more fused benzene rings. Many of the polycyclic compounds included in this report display properties of interest in the field of materials science and some can be considered as nano‐sized graphene substructures or nanographenes.
Multispectral simultaneous diagnosis of Saturn's aurorae throughout a planetary rotation
Authors: Lamy L. , Prangé R. , Pryor W. , Gustin J. , Badman S. V. , Melin H. , Stallard T. , Mitchell D. G. , Brandt P. C.
Published: July 2013

From 27 to 28 January 2009, the Cassini spacecraft remotely acquired combined observations of Saturn's southern aurorae at radio, ultraviolet, and infrared wavelengths, while monitoring ion injections in the middle magnetosphere from energetic neutral atoms. Simultaneous measurements included the sampling of a full planetary rotation, a relevant timescale to investigate auroral emissions driven by processes internal to the magnetosphere. In addition, this interval coincidentally matched a powerful substorm‐like event in the magnetotail, which induced an overall dawnside intensification of the magnetospheric and auroral activity. We comparatively analyze this unique set of measurements to reach a comprehensive view of kronian auroral processes over the investigated timescale. We identify three source regions for the atmospheric aurorae, including a main oval associated with the bulk of Saturn Kilometric Radiation (SKR), together with polar and equatorward emissions. These observations reveal the coexistence of corotational and subcorototational dynamics of emissions associated with the main auroral oval. Precisely, we show that the atmospheric main oval hosts short‐lived subcorotating isolated features together with a bright, longitudinally extended, corotating region locked at the southern SKR phase. We assign the substorm‐like event to a regular, internally driven, nightside ion injection possibly triggered by a plasmoid ejection. We also investigate the total auroral energy budget, from the power input to the atmosphere, characterized by precipitating electrons up to 20 keV, to its dissipation through the various radiating processes. Finally, through simulations, we confirm the search‐light nature of the SKR rotational modulation and we show that SKR arcs relate to isolated auroral spots. We characterize which radio sources are visible from the spacecraft and we estimate the fraction of visible southern power to a few percent. The resulting findings are discussed in the frame of pending questions as the persistence of a corotating field‐aligned current system within a subcorotating magnetospheric cold plasma, the occurrence of plasmoid activity, and the comparison of auroral fluxes radiated at different wavelengths.
Making sense of cultural distance for military expatriates operating in an extreme context
Authors: Fisher Kelly , Hutchings Kate
Published: July 2013

This research examines the relationship between cultural distance (CD) and intercultural adjustment for Australian military advisers who trained and lead foreign soldiers during the Vietnam War. Situated cognition is used to identify six salient attributes of CD for the military advisers, and a conceptual framework is proposed on the basis of shared mental models (schemata) that illustrate the relationship between CD and expatriate adjustment in an extreme context. The findings highlight the significance of professional and ethical differences between the Australians and Vietnamese, foreignness, language, political and social milieu, and face management. The research is significant in the following: extending the literature on CD and expatriate adjustment from an erstwhile overwhelming focus on adjustment in a mundane environment to the extreme context in which poor intercultural collaboration can have potentially life‐threatening effects; highlighting the role of “boundary spanners” in intercultural collaborations and negotiations; and providing insights into human behavior in a complex, dynamic context for other organizations operating in an extreme context. Copyright © 2013 John Wiley & Sons, Ltd.
Dynamics of natural prokaryotes, viruses, and heterotrophic nanoflagellates in alpine karstic groundwater
Authors: Wilhartitz Inés C. , Kirschner Alexander K. T. , Brussaard Corina P. D. , Fischer Ulrike R. , Wieltschnig Claudia , Stadler Hermann , Farnleitner Andreas H.
Published: July 2013

Seasonal dynamics of naturally occurring prokaryotes, viruses, and heterotrophic nanoflagellates in two hydro‐geologically contrasting alpine karst springs were monitored over three annual cycles. To our knowledge, this study is the first to shed light on the occurrence and possible interrelationships between these three groups in karstic groundwater. Hydrological and microbiological standard indicators were recovered simultaneously in order to estimate surface influence, especially during rainfall events. Data revealed a strong dependence of the microbial communities on the prevailing hydrological situation. Prokaryotic numbers averaged 5.1 × 107 and 1.3 × 107 cells L−1, and heterotrophic nanoflagellate abundance averaged 1.1 × 104 and 3 × 103 cells L−1 in the limestone spring type (LKAS2) and the dolomitic spring type (DKAS1), respectively. Viral abundance in LKAS2 and DKAS1 averaged 9.4 × 108 and 1.1 × 108 viruses L−1. Unlike in DKAS1, the dynamic spring type LKAS2 revealed a clear difference between base flow and high discharge conditions. The virus‐to‐prokaryotes ratio was generally lower by a factor of 2–3, at higher average water residence times. Furthermore, the high prokaryotes‐to‐heterotrophic nanoflagellate ratios, namely about 4700 and 5400 for LKAS2 and DKAS1, respectively, pointed toward an uncoupling of these two groups in the planktonic fraction of alpine karstic aquifers.
Structure of P3HT in the solid state
Authors: de Oliveira Eliézer Fernando , Lavarda Francisco Carlos
Published: July 2013

Poly(3‐hexylthiophene) (P3HT) is a polymer widely used in organic photovoltaic devices. Discrepancies in information exist in the literature about its morphological structure in solution and in the solid state. This work is a theoretical study, in which the structure of P3HT in the solid state is deduced from its structure in solution and comparisons with optical absorption data. The results indicate that P3HT is not planar, either in solution or in the solid state. However, the effective conjugation length in the solid state is similar to that of a planar chain. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1350–1354
Novel Insights into the Pharmacology of Flavonoids
Authors: Romano Barbara , Pagano Ester , Montanaro Vittorino , Fortunato Alfonso L. , Milic Natasa , Borrelli Francesca
Published: July 2013

Flavonoids are widely distributed secondary metabolites and currently consumed in large amounts in the daily diet. In this article, some of the most recent developments in flavonoid – and related polyphenolic compounds – pharmacology are discussed, with particular emphasis on very recent data, most of which are published in Phytotherapy Research, which highlight new aspects in flavonoid anti‐inflammatory, antilipidemic, antihyperglycemic, antiviral, hepatoprotective, gastric antiulcer, cardioprotective, neuroprotective, antioxidant and anticancer actions. These updated data confirm the well‐established diverse beneficial pharmacological actions and might support the perspective for a therapeutic use. Copyright © 2013 John Wiley & Sons, Ltd.
An investigation of college chemistry students' understanding of structure–property relationships
Authors: Cooper Melanie M. , Corley Leah M. , Underwood Sonia M.
Published: July 2013

The connection between the molecular‐level structure of a substance and its macroscopic properties is a fundamental concept in chemistry. Students in college‐level general and organic chemistry courses were interviewed to investigate how they used structure–property relationships to predict properties such as melting and boiling points. Although student difficulties in this area are well documented, they are usually classified as individual misconceptions. However our studies showed that student problems appear to arise from a complex interplay of problems involving a number of different sources: (1) models of phases/phase change, (2) use of representations, (3) language and terminology, and (4) use of heuristics in student reasoning. No two students used the same sets of ideas to perform the task at hand, and while we did see some recurrences of a single idea or heuristic, the ways that students combined them were different. We believe that, at least for high‐level complex tasks such as determining structure–property relationships, student understanding is best understood as a set of loosely connected ideas, skills, and heuristics that are not well integrated. These are not single “misconceptions” that can be reconstructed in isolation. What is clear is that students who have done everything we ask of them, and who have earned high grades in chemistry courses are unable to address a core concept in chemistry. Typical assessments often mask the difficulties that students have with core concepts, since many students may correctly answer a question using heuristics, but have faulty reasoning. We recommend that instruction should include a scaffolded progression of ideas, and opportunities to construct and connect their understanding that will allow students to construct a more coherent framework from which to make predictions about the behavior of matter.
Deformation and exhumation of the Ronda peridotite (Spain)
Authors: Précigout Jacques , Gueydan Frédéric , Garrido Carlos J. , Cogné Nathan , Booth‐Rea Guillermo
Published: July 2013

The Ronda peridotite supplies one of the best objects to document subcontinental mantle deformation, but its internal deformation and exhumation mechanisms remain controversial. Here we provide new structural data and numerical results that constrain the Oligocene‐Miocene deformation history of the Ronda massif. We first describe a mantle shear zone in the northern massif that developed subcrustal strain localization during decompression and related partial melting. The deformation regime of this mantle shear zone evolved from penetrative NE‐SW stretching to sinistral shear highlighted by discrete shear bands. We then show structural observations that document a viscous deformation in the southern massif occurring prior to the thrust‐assisted emplacement of the peridotite during large decompression. Finally, we performed numerical investigations that quantify a high temperature of 980°C for the basal peridotite lens at the time of its crustal emplacement. Our numerical results constrain the timing of ductile deformation of the peridotite just before 22 Ma, probably between 30 and 22 Ma. Altogether, these features led us to conclude that the deformation and exhumation of the Ronda peridotite results from lithosphere thinning subsequently inverted in the course of the Oligocene‐Miocene. Among available models, our findings support the hypothesis of peridotite exhumation by the inversion of a thinned back‐arc continental lithosphere during westward slab rollback through the Alboran region.
Inflammatory Pseudotumours in the Abdomen and Pelvis: A Pictorial Essay
Authors: Sedlic Tony , Scali Elena P. , Lee Wai-Kit , Verma Sadhna , Chang Silvia D.
Published: July 2013

Inflammatory pseudotumours are uncommonly encountered lesions in the abdomen and pelvis that often present with variable and nonspecific imaging features. They may mimic other more common lesions, including malignancy. Within the appropriate clinical context, inflammatory pseudotumours merit consideration in the differential diagnosis of soft-tissue masses within the abdomen and pelvis. A preoperative diagnosis of inflammatory pseudotumour, established through biopsy, may help to differentiate this benign entity from malignancy. In this article, we reviewed the imaging features of inflammatory pseudotumours of the abdomen and pelvis, including liver, spleen, bowel, retroperitoneum, kidney, bladder, uterus, and adnexa.
Assessing Postdisaster Psychological Stress in Hazardous Waste Operations and Emergency Response (HAZWOPER) Workers
Authors: Calcote Joshua C. , Carson Arch I. , Peskin Melissa F. , Emery Robert J.
Published: July 2013

Objective

To assess the prevalence of traumatic stress experienced by secondary responders to disaster events to determine if mental health education should be included in HAZWOPER training.

Methods

Preexisting survey tools for assessing posttraumatic stress disorder (PTSD), resiliency, and mental distress were combined to form a web-based survey tool that was distributed to individuals functioning in secondary response roles. Data were analyzed using the Fisher exact test, 1-way ANOVA, and 1-samplettests.

Results

Respondents reported elevated PTSD levels (32.9%) as compared to the general population. HAZWOPER-trained responders with disaster work experience were more likely to be classified as PTSD positive as compared to untrained, inexperienced responders and those possessing only training or experience. A majority (68.75%) scored below the mean resiliency level of 80.4 on the Connor-Davidson Resilience Scale. Respondents with only training or both training and experience were more likely to exhibit lower resiliency scores than those with no training or experience. PTSD positivity correlated with disaster experience. Among respondents, 91% indicated support for mental health education.

Conclusions

Given the results of the survey, consideration should be given to the inclusion of pre- and postdeployment mental health education in the HAZWOPER training regimen. (Disaster Med Public Health Preparedness. 2013;0:1-9)
Effects of a multi-micronutrient-fortified beverage, with and without sugar, on growth and cognition in South African schoolchildren: a randomised, double-blind, controlled intervention
Authors: Taljaard Christine , Covic Namukolo M. , van Graan Averalda E. , Kruger Herculina S. , Smuts Cornelius M. , Baumgartner Jeannine , Kvalsvig Jane D. , Wright Hattie H. , van Stuijvenberg Martha E. , Jerling Johann C.
Published: July 2013

Little is known about the effects of combined micronutrient and sugar consumption on growth and cognition. In the present study, we investigated the effects of micronutrients and sugar, alone and in combination, in a beverage on growth and cognition in schoolchildren. In a 2 × 2 factorial design, children (n414, 6–11 years) were randomly allocated to consume beverages containing (1) micronutrients with sugar, (2) micronutrients with a non-nutritive sweetener, (3) no micronutrients with sugar or (4) no micronutrients with a non-nutritive sweetener for 8·5 months. Growth was assessed and cognition was tested using the Kaufman Assessment Battery for Children version II (KABC-II) subtests and the Hopkins Verbal Learning Test (HVLT). Micronutrients decreased the OR for Fe deficiency at the endpoint (OR 0·19; 95 % CI 0·07, 0·53). Micronutrients increased KABC Atlantis (intervention effect: 0·76; 95 % CI 0·10, 1·42) and HVLT Discrimination Index (1·00; 95 % CI 0·01, 2·00) scores. Sugar increased KABC Atlantis (0·71; 95 % CI 0·05, 1·37) and Rover (0·72; 95 % CI 0·08, 1·35) scores and HVLT Recall 3 (0·94; 95 % CI 0·15, 1·72). Significant micronutrient × sugar interaction effects on the Atlantis, Number recall, Rover and Discrimination Index scores indicated that micronutrients and sugar in combination attenuated the beneficial effects of micronutrients or sugar alone. Micronutrients or sugar alone had a lowering effect on weight-for-agez-scores relative to controls (micronutrients − 0·08; 95 % CI − 0·15, − 0·01; sugar − 0·07; 95 % CI − 0·14, − 0·002), but in combination, this effect was attenuated. The beverages with micronutrients or added sugar alone had a beneficial effect on cognition, which was attenuated when provided in combination.
Connectedness properties of the set where the iterates of an entire function are bounded
Authors: OSBORNE JOHN
Published: July 2013

We investigate some connectedness properties of the set of points K(f) where the iterates of an entire function f are bounded. We describe a class of transcendental entire functions for which K(f) is totally disconnected if and only if each component of K(f) containing a critical point is aperiodic. Moreover we show that, for such functions, if K(f) is disconnected then it has uncountably many components. We give examples of functions for which K(f) is totally disconnected and we use quasiconformal surgery to construct a function for which K(f) has a component with empty interior that is not a singleton.
A review of cognitive therapy in acute medical settings. Part II: Strategies and complexities
Authors: Levin Tomer T. , White Craig A. , Bialer Philip , Charlson Robert W. , Kissane David W.
Published: July 2013

Objective:

Cognitive therapy (CT) has considerable utility for psychosomatic medicine (PM) in acute medical settings but, to date, no such cohesive adaptation has been developed. Part I delineated a CT model for acute medical settings focusing on assessment and formulation. In Part II, we review how CT can be applied to common PM clinical challenges. A pragmatic approach is helpful because this review targets PM trainees and educators.

Methods:

Narrative review is used to discuss the application of CT strategies to common challenges in acute medical settings. Treatment complexities and limitations associated with the PM setting are detailed. Exemplary dialogues are used to model techniques.

Result:

We present CT approaches to eight common scenarios: (1) distressed or hopeless patients; (2) patients expressing pivotal distorted cognitions/images; (3) patients who catastrophize; (4) patients who benefit from distraction and activation strategies; (5) panic and anxiety; (6) suicidal patients; (7) patients who are stuck and helpless; (8) inhibited patients. Limitations are discussed.

Significance of results:

A CT informed PM assessment, formulation and early intervention with specific techniques offers a novel integrative framework for psychotherapy with the acutely medically ill. Future efforts should focus on dissemination, education of fellows and building research efficacy data.
Renal denervation - a clinical update and future directions
Authors: Mortensen Kai , Franzen Klaas , Reppel Michael , Weil Joachim
Published: July 2013

The aim of this review is to give a contemporary update on renal denervation therapy focusing particularly on the scientific background and present literature as well as on different technical approaches and potential future directions.
Einstellungen zum Einbezug der Erstsprache im Kindergarten und deren Bedeutung für die Wortschatzentwicklung im Deutschen bei Kindern mit Migrationshintergrund
Authors: Kratzmann Jens , Lehrl Simone , Ebert Susanne
Published: July 2013

Der Beitrag untersucht anhand einer Stichprobe von 188 Kindern mit Migrationshintergrund im Alter von 3 – 5 Jahren der Längsschnittstudie BiKS-3 – 10, welche Bedeutung die Einstellung der Erzieherin zur Integration der Erstsprache in der Kindertagesstätte für die Wortschatzentwicklung im Deutschen hat. Hierzu wurde der rezeptive Wortschatz im Deutschen zu drei Messzeitpunkten im Abstand von jeweils einem Jahr erfasst und anhand von latenten Wachstumsmodellen modelliert. Neben den Einstellungen von Erzieherinnen werden auch strukturelle und prozessuale Merkmale aus Familie und Kindergarten berücksichtigt. Es zeigen sich negative Effekte einer erstsprachintegrierenden Einstellung auf die Wortschatzentwicklung im Deutschen für Kinder, in deren Familien die Erstsprache gepflegt wird, und in Kindertagesstätten mit einem hohen Anteil an Kindern mit Migrationshintergrund.
Low temperature delays timing and enhances the cost of nitrogen fixation in the unicellular cyanobacterium Cyanothece
Authors: Brauer Verena S , Stomp Maayke , Rosso Camillo , van Beusekom Sebastiaan A M , Emmerich Barbara , Stal Lucas J , Huisman Jef
Published: July 2013

Marine nitrogen-fixing cyanobacteria are largely confined to the tropical and subtropical ocean. It has been argued that their global biogeographical distribution reflects the physiologically feasible temperature range at which they can perform nitrogen fixation. In this study we refine this line of argumentation for the globally important group of unicellular diazotrophic cyanobacteria, and pose the following two hypotheses: (i) nitrogen fixation is limited by nitrogenase activity at low temperature and by oxygen diffusion at high temperature, which is manifested by a shift from strong to weak temperature dependence of nitrogenase activity, and (ii) high respiration rates are required to maintain very low levels of oxygen for nitrogenase, which results in enhanced respiratory cost per molecule of fixed nitrogen at low temperature. We tested these hypotheses in laboratory experiments with the unicellular cyanobacterium Cyanothece sp. BG043511. In line with the first hypothesis, the specific growth rate increased strongly with temperature from 18 to 30 °C, but leveled off at higher temperature under nitrogen-fixing conditions. As predicted by the second hypothesis, the respiratory cost of nitrogen fixation and also the cellular C:N ratio rose sharply at temperatures below 21 °C. In addition, we found that low temperature caused a strong delay in the onset of the nocturnal nitrogenase activity, which shortened the remaining nighttime available for nitrogen fixation. Together, these results point at a lower temperature limit for unicellular nitrogen-fixing cyanobacteria, which offers an explanation for their (sub)tropical distribution and suggests expansion of their biogeographical range by global warming.
Multifactorial diversity sustains microbial community stability
Authors: Erkus Oylum , de Jager Victor C L , Spus Maciej , van Alen-Boerrigter Ingrid J , van Rijswijck Irma M H , Hazelwood Lucie , Janssen Patrick W M , van Hijum Sacha A F T , Kleerebezem Michiel , Smid Eddy J
Published: July 2013

Maintenance of a high degree of biodiversity in homogeneous environments is poorly understood. A complex cheese starter culture with a long history of use was characterized as a model system to study simple microbial communities. Eight distinct genetic lineages were identified, encompassing two species: Lactococcus lactis and Leuconostoc mesenteroides. The genetic lineages were found to be collections of strains with variable plasmid content and phage sensitivities. Kill-the-winner hypothesis explaining the suppression of the fittest strains by density-dependent phage predation was operational at the strain level. This prevents the eradication of entire genetic lineages from the community during propagation regimes (back-slopping), stabilizing the genetic heterogeneity in the starter culture against environmental uncertainty.
Optically Induced Thermal Gradients for Protein Characterization in Nanolitre-scale Samples in Microfluidic Devices
Authors: Sagar D. M. , Aoudjane Samir , Gaudet Matthieu , Aeppli Gabriel , Dalby Paul A.
Published: July 2013

Proteins are the most vital biological functional units in every living cell. Measurement of protein stability is central to understanding their structure, function and role in diseases. While proteins are also sought as therapeutic agents, they can cause diseases by misfolding and aggregation in vivo. Here we demonstrate a novel method to measure protein stability and denaturation kinetics, on unprecedented timescales, through optically-induced heating of nanolitre samples in microfluidic capillaries. We obtain protein denaturation kinetics as a function of temperature and accurate thermodynamic stability data, from a snapshot experiment on a single sample. We also report the first experimental characterization of optical heating in controlled microcapillary flow, verified by computational fluid dynamics modelling. Our results demonstrate that we now have the engineering science in hand to design integrated all-optical microfluidic chips for a diverse range of applications including in-vitro DNA amplification, healthcare diagnostics and flow chemistry.
Mitochondrion-associated protein LRPPRC suppresses the initiation of basal levels of autophagy via enhancing Bcl-2 stability
Authors: Zou Jing , Yue Fei , Jiang Xianhan , Li Wenjiao , Yi Jinglin , Liu Leyuan
Published: July 2013

The mitochondrion-associated protein LRPPRC (leucine-rich pentatricopeptide repeat-containing) interacts with one of the microtubule-associated protein family members MAP1S (microtubule-associated protein 1 small form), originally named C19ORF5 (chromosome 19 open reading frame 5), to form a complex. MAP1S interacts with LC3 (light chain 3), the mammalian homologue of yeast autophagy marker ATG8 and one of the most important autophagy markers in mammalian cells, and helps the attachment of autophagosomes with microtubules for trafficking and recruitment of substrate mitochondria into autophagosomes for degradation. MAP1S activates autophagosomal biogenesis and degradation to remove misfolded/aggregated proteins and dysfunctional organelles such as mitochondria and suppress oxidative stress-induced genomic instability and tumorigenesis. Previously, various studies have attributed LRPPRC nucleic acid-associated functions. Instead, in the present study, we show that LRPPRC associates with mitochondria, interacts with Beclin 1 and Bcl-2 and forms a ternary complex to maintain the stability of Bcl-2. Suppression of LRPPRC leads to reduction in mitochondrial potential and reduction in Bcl-2. Lower levels of Bcl-2 lead to release of more Beclin 1 to form the Beclin 1–PI3KCIII (class III phosphoinositide 3-kinase) complex to activate autophagy and accelerate the turnover of dysfunctional mitochondria through the PI3K (phosphoinositide 3-kinase)/Akt/mTOR (mammalian target of rapamycin) pathway. The activation of autophagy induced by LRPPRC suppression occurs upstream of the ATG5–ATG12 conjugate-mediated conversion of LC3-I into LC3-II and has been confirmed in multiple mammalian cell lines with multiple autophagy markers including the size of GFP–LC3 punctate foci, the intensity of LC3-II and p62 protein and the size of the vacuolar structure. The activated autophagy enhances the removal of mitochondria through lysosomes. LRPPRC therefore acts to suppress the initiation of basal levels of autophagy to clean up dysfunctional mitochondria and other cellular debris during the normal cell cycle.
Chemical suppression of an oncogenic splicing variant of AIMP2 induces tumour regression
Authors: Lee Hee Sook , Kim Dae Gyu , Oh Young Sun , Kwon Nam Hoon , Lee Jin Young , Kim Doyeun , Park Song-Hwa , Song Jong-Hwan , Lee Sunkyung , Han Jung Min , Park Bum-Joon , Lee Jongkook , Kim Sunghoon
Published: July 2013

AIMP2 (aminoacyl-tRNA synthetase-interacting multifunctional protein 2) is a potent tumour suppressor that induces apoptosis in response to various oncogenic signals. AIMP2-DX2, an exon2-deleted splicing variant of AIMP2, is up-regulated in lung cancer and competitively suppresses the pro-apoptotic activity of AIMP2, resulting in tumorigenesis. In the present study we report that BC-DXI01, a synthetic compound, specifically reduces the cellular levels of AIMP2-DX2 through selective degradation of the AIMP2-DX2 mRNA transcript. We found that BC-DXI01-mediated cell death positively correlates with AIMP2-DX2 expression in the lung cancer cell lines tested. Administration of BC-DXI01 in a AIMP2-DX2-driven tumour xenograft mice model led to reduced tumour sizes and volumes of up to 60% in comparison with vehicle-treated mice group, consistent with decreases in AIMP2-DX2 transcript and protein levels. Taken together, our findings suggest that tumorigenic activity of AIMP2-DX2 can be controlled by the small chemical BC-DXI01, which can selectively suppress the AIMP2-DX2 mRNA transcript.
Laser comminution of submerged samples
Authors: Mariella R. , Rubenchik A. , Norton M. , Donohue G.
Published: July 2013

With the long-term goal in mind of investigating possible designs for a “universal, solid-sample comminution technique” for elemental analysis of debris and rubble, we have studied pulsed-laser ablation of solid samples that were submerged in water. Using 351-nm, 15-ns laser pulses with energy between 1 J and 0.35 J, intensities between 500 MW/cm2 and 30 MW/cm2, and samples of broken rock [quartzite] and concrete debris, we have observed conditions in which the laser-driven process can remove material from the solid target substrate, dissolving it and/or converting it into ultrafine particles in a controlled manner. Our study used impure, non-metallic substrates and investigated both the rate of material removal as well as the size distribution of particles that were ablated from the process. We studied ablation at lower regimes of intensity and fluence [below 100 MW/cm2 and 0.4 J/cm2, respectively] than has previously attracted attention and discovered that there appears to be a new regime for energy-efficient material removal [Q* < 4000 J/g, for quartzite and <2000 J/g for concrete] and for the generation of ultrafine particles.
Finite-field implementation of NMR chemical shieldings for molecules: Direct and converse gauge-including projector-augmented-wave methods
Authors: Vasconcelos Filipe , de Wijs Gilles A. , Havenith Remco W. A. , Marsman Martijn , Kresse Georg
Published: July 2013

Two finite-field implementations for the calculation of chemical shieldings of molecular systems using a plane-wave basis set and the Gauge-Including Projector-Augmented-Wave method are presented. The direct approach mimics the nuclear magnetic resonance experiment in that it puts the molecule in a uniform magnetic field and obtains shieldings from the current response. The other is based on the recently introduced “converse method” [T. Thonhauser, D. Ceresoli, A. A. Mostofi et al., J. Chem. Phys. 131, 101101 (2009)]10.1063/1.3216028. In both methods two-center contributions to the shieldings can be included via a numerically simple augmentation construction. Results obtained with both methods are discussed as well as (dis)similarities in their behaviors.
Molecular dynamics simulations of n-hexane at 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide interface
Authors: Lísal Martin , Izák Pavel
Published: July 2013

Molecular dynamics simulations of n-hexane adsorbed onto the interface of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([bmim][Tf2N]) are performed at three n-hexane surface densities, ranged from 0.7 to 2.3 μmol/m2 at 300 K. For [bmim][Tf2N] room-temperature ionic liquid, we use a non-polarizable all-atom force field with the partial atomic charges based on ab initio calculations for the isolated ion pair. The net charges of the ions are ±0.89e, which mimics the anion to cation charge transfer and polarization effects. The OPLS-AA force field is employed for modeling of n-hexane. The surface tension is computed using the mechanical route and its value decreases with increase of the n-hexane surface density. The [bmim][Tf2N]/n-hexane interface is analyzed using the intrinsic method, and the structural and dynamic properties of the interfacial, sub-interfacial, and central layers are computed. We determine the surface roughness, global and intrinsic density profiles, and orientation ordering of the molecules to describe the structure of the interface. We further compute the survival probability, normal and lateral self-diffusion coefficients, and re-orientation correlation functions to elucidate the effects of n-hexane on dynamics of the cations and anions in the layers.
Symmetrical mixtures in external fields
Authors: Materniak S. , Patrykiejew A.
Published: July 2013

We have studied the behavior of symmetrical binary mixtures of Lennard-Jones particles in contact with strongly adsorbing walls using Monte Carlo simulation methods in the grand canonical and semi-grand canonical ensembles. Two types of the surface potential have been applied. The first depends on the distance from the surface only, while the second involves periodic modulations in the directions parallel to the wall. In the latter case, it has been assumed that the solid substrate is a fcc crystal with the surface being the (100) face. We have considered the systems in which the surface potential is strong enough to induce the layer-by-layer adsorption at low temperatures and discussed the interplay between the demixing transition and the structure of thin films for several systems characterized by different parameters describing the interactions in the system.
Density modification by two superposing TE10 modes in a plasma filled rectangular waveguide
Authors: Tomar Sanjay K. , Malik Hitendra K.
Published: July 2013

Microwave and plasma interaction is examined via two fundamental TE10 modes propagating in a plasma filled rectangular waveguide after superposing at a smaller angle. The propagation of the resultant mode realized from these two modes is governed by a wave equation obtained using the Maxwell's equations. This equation is solved numerically using fourth order Runge-Kutta method for the field amplitude of the microwave in the waveguide considering the waveguide to be made up of a perfect conductor and filled with different types of initial plasma density distributions, viz. homogeneous density, linear density with gradient in the propagation direction, and the density with Gaussian profile along the waveguide width. A phenomenon similar to the duct formation by high power microwaves is found to take place, where the plasma density attains interesting profiles. These profiles can be controlled by the angle of superposition, phase difference between the fields of the two modes, microwave frequency and microwave field amplitude.
Raman studies of spin-phonon coupling in hexagonal BaFe12O19
Authors: Chen Xiang-Bai , Minh Hien Nguyen Thi , Han Kiok , Chul Sur Jung , Sung N. H. , Cho B. K. , Yang In-Sang
Published: July 2013

Phonon softening in hexagonal BaFe12O19 single crystal is observed in temperature dependent polarized Raman spectroscopy. The phonon softening is significantly enhanced below ∼80 K, at which the magnetization in a magnetic field along c-axis shows a clear change in the temperature dependence, indicating a magnetic phase transition near 80 K. Possible interpretations of the anomalous temperature dependence of the phonon frequencies–phonon softening behaviors are discussed. The phonon softening would be correlated to local structural and magnetic phase transition in hexagonal BaFe12O19, in which the spin-phonon coupling would have major contribution for the phonon softening. We also discuss that the spin-phonon coupling would be affected by both the spin ordering and the individual phonon vibration in magnetic material.
High quality factor mg-scale silicon mechanical resonators for 3-mode optoacoustic parametric amplifiers
Authors: Torres F. A. , Meng P. , Ju L. , Zhao C. , Blair D. G. , Liu K.-Y. , Chao S. , Martyniuk M. , Roch-Jeune I. , Flaminio R. , Michel C.
Published: July 2013

Milligram-scale resonators have been shown to be suitable for the creation of 3-mode optoacoustic parametric amplifiers, based on a phenomena first predicted for advanced gravitational-wave detectors. To achieve practical optoacoustic parametric devices, high quality factor resonators are required. We present millimetre-scale silicon resonators designed to exhibit a torsional vibration mode with a frequency in the 105–106 Hz range, for observation of 3-mode optoacoustic interactions in a compact table-top system. Our design incorporates an isolation stage and minimizes the acoustic loss from optical coating. We observe a quality factor of 7.5 × 105 for a mode frequency of 401.5 kHz, at room temperature and pressure of 10–3 Pa. We confirmed the mode shape by mapping the amplitude response across the resonator and comparing to finite element modelling. This study contributes to the development of 3-mode optoacoustic parametric amplifiers for use in novel high-sensitivity signal transducers and quantum measurement experiments.
Microarray of non-connected gold pads used as high density electric traps for parallelized pairing and fusion of cells
Authors: Hamdi Feriel S. , Français Olivier , Subra Frederic , Dufour-Gergam Elisabeth , Le Pioufle Bruno
Published: July 2013

Cell fusion consists of inducing the formation of a hybridoma cell containing the genetic properties of the progenitor cells. Such an operation is usually performed chemically or electrically. The latter method, named electrofusion, is considered as having a strong potential, due to its efficiency and non-toxicity, but deserves further investigations prior to being applicable for key applications like antibody production and cancer immunotherapy. Indeed, to envision such applications, a high amount of hybrid cells is needed. In this context, we present in this paper a device for massive cell pairing and electrofusion, using a microarray of non-connected conductive pads. The electrofusion chamber––or channel––exposes cells to an inhomogeneous electric field, caused by the pads array, enabling the trapping and pairing of cells with dielectrophoresis (DEP) forces prior to electrofusion. Compared to a mechanical trapping, such electric trapping is fully reversible (on/off handling). The DEP force is contactless and thus eases the release of the produced hybridoma. Moreover, the absence of wire connections on the pads permits the high density trapping and electrofusion of cells. In this paper, the electric field mapping, the effect of metallic pads thickness, and the transmembrane potential of cells are studied based on a numerical model to optimize the device. Electric calculations and experiments were conducted to evaluate the trapping force. The structure was finally validated for cell pairing and electrofusion of arrays of cells. We believe that our approach of fully electric trapping with a simple structure is a promising method for massive production of electrofused hybridoma.
Electric field engineering using quantum-size-effect-tuned heterojunctions
Authors: Adinolfi V. , Ning Z. , Xu J. , Masala S. , Zhitomirsky D. , Thon S. M. , Sargent E. H.
Published: July 2013

A quantum junction solar cell architecture was recently reported that employs colloidal quantum dots (CQDs) on each side of the p-n junction. This architecture extends the range of design opportunities for CQD photovoltaics, since the bandgap can be tuned across the light-absorbing semiconductor layer via control over CQD size, employing solution-processed, room-temperature fabricated materials. We exploit this feature by designing and demonstrating a field-enhanced heterojunction architecture. We optimize the electric field profile within the solar cell through bandgap engineering, thereby improving carrier collection and achieving an increased open circuit voltage, resulting in a 12% improvement in power conversion efficiency.
Probing the nature of carrier localization in GaInNAs epilayers by optical methods
Authors: Tsai Y. , Barman B. , Scrace T. , Lindberg G. , Fukuda M. , Whiteside V. R. , Keay J. C. , Johnson M. B. , Sellers I. R. , Al Khalfioui M. , Leroux M. , Weinstein B. A. , Petrou A.
Published: July 2013

Photoluminescence (PL), optical pumping, and reflectance studies of nominally undoped and p-type GaInNAs epilayers are presented. The PL peak energy of the nominally undoped sample exhibits an S-shaped dependence on temperature for T < 50 K. This is attributed to recombination of bound excitons localized on traps. The energy of the PL circular-polarization maximum coincides with the energy of the free-exciton related reflectance feature at all temperatures. In heavily p-type samples the S-shaped temperature-dependence of the PL energy disappears, and the PL peak and circular polarization maximum coincide with the reflectance feature at all temperatures, indicating that the PL is free-exciton-like.
Corrigendum to: Prevalence and prevention of workplace aggression in Australian clinical medical practice
Authors: Hills Danny J. , Joyce Catherine M. , Humphreys John S.
Published: July 2013

Objective.
To determine the extent of aggression directed towards Australian doctors and the implementation of aggression prevention and minimisation strategies in medical workplaces.

Methods.
Data were obtained from the pilot phase (n = 321) of the Medicine in Australia: Balancing Employment and Life survey of the clinical medical workforce in 2010. Descriptive statistics were generated in relation to doctors' experiences of aggression at work in the previous 12 months, and the implementation of workplace aggression prevention and minimisation strategies. Distributions of the outcome variables were evaluated by doctor type and sex.

Results.
More than 70% of doctors experienced verbal or written aggression and almost a third experienced physical aggression. Higher proportions of hospital non-specialists and specialists-in-training experienced aggression from patients, patient relatives or carers and co-workers. Higher proportions of female doctors experienced verbal or written aggression from patient relatives or carers and co-workers. Overall, the more basic aggression prevention and minimisation strategies had been implemented in approximately two-thirds of clinical settings, with lower rates for more extended strategies.

Conclusions.
Many Australian doctors experience workplace aggression. The more widespread adoption of measures that support the prevention and minimisation of aggression in medical practice settings appears necessary.

What is known about the topic?
The limited research on workplace aggression in Australian medical practice primarily focusses on the prevalence of patient aggression in General Practice.

What does this paper add?
Current evidence is provided on the extent of workplace aggression directed towards Australian doctors from multiple sources and the implementation of workplace aggression prevention and minimisation strategies in diverse clinical settings.

What are the implications for practitioners?
More concerted efforts need to be undertaken to ensure that effective aggression prevention and minimisation strategies are implemented in medical practice.