bluuebunny/crossref_metadata_2025 huggingface dataset:
Reduction in radiation‐induced lymphocytopenia by famotidine in patients undergoing radiotherapy for prostate cancer
Authors: Razzaghdoust Abolfazl , Mozdarani Hossein , Mofid Bahram , Aghamiri S. Mahmoud R. , Heidari Amir H.
Published: September 2013

BACKGROUND

Ionizing radiation causes a series of hematological alterations especially profound lymphocytopenia during and after the radiotherapy course. To investigate whether famotidine can reduce hematologic toxicity in patients treated with radiotherapy for prostate cancer.

METHODS

A total of 36 patients undergoing radiotherapy for prostate cancer were randomized to receive either placebo or famotidine tablets. Participants were pretreated with 40 mg of oral famotidine or placebo tablets twice daily, 4 and 3 hr before each radiotherapy fraction. The patients received external‐beam radiotherapy up to 70 Gy. Complete blood counts with differential, platelet counts, and hemoglobin levels were obtained at baseline, biweekly during the treatment and once 4 weeks after the end of radiotherapy course. Magnitude of changes from baseline in the hematological parameters was determined and compared using Repeated Measures ANOVA.

RESULTS

Famotidine was well tolerated. A total of 112 blood samples were evaluated. A significant reduction in radiation‐induced lymphocytopenia was noted in patients receiving famotidine than in patients receiving placebo (P = 0.006). No significant difference was observed between two groups for the decline in platelets, erythrocytes and leucocytes. For both groups, neutrophil, monocyte, eosinophil, and hemoglobin levels did not change significantly during the treatment.

CONCLUSIONS

Our results indicate that famotidine could result in a significant reduction in radiation‐induced lymphocytopenia and may consequently increase radiotherapy efficacy as well as survival times. This radioprotective effect may be chiefly associated with its antioxidant and radical scavenging properties. Further studies are required to confirm these encouraging results.Prostate 74:41–47, 2014. © 2013 Wiley Periodicals, Inc.
Are ARBs now first‐line therapy for hypertension?
Authors: McInnes Gordon
Published: September 2013

Now that generic ARBs are available and ACE inhibitors have consequently lost their cost advantage, Professor McInnes makes the case for starting antihypertensive treatment with an ARB.
Pharma deals for CCGs: too hard to ignore?
Authors: Singh Inderjit
Published: September 2013

GPs working in CCGs now have a role in managing the entry of drugs into their local formularies. The author describes the various schemes offered by manufacturers that allow CCGs to make savings when their products are purchased.
Venturing from Emerging Economies
Authors: Yamakawa Yasuhiro , Khavul Susanna , Peng Mike W. , Deeds David L.
Published: September 2013

What drives new ventures to internationalize from emerging economies to developed economies? To answer this underexplored question, we bring together theory at the intersection of international entrepreneurship and strategy in emerging economies. Focusing on intangible resources, we theorize that international expansion of new ventures from emerging economies is driven by their desire to enhance domestic reputation, to exploit their stocks of prior knowledge, and to explore benefits of incoming knowledge flows. We find support for our hypotheses using a cross‐country sample of new ventures from two major emerging economies—China and India. Copyright © 2013 Strategic Management Society.
Size‐Controlled Soft‐Template Synthesis of Carbon Nanodots toward Versatile Photoactive Materials
Authors: Kwon Woosung , Lee Gyeongjin , Do Sungan , Joo Taiha , Rhee Shi‐Woo
Published: September 2013

Size‐controlled soft‐template synthesis of carbon nanodots (CNDs) as novel photoactive materials is reported. The size of the CNDs can be controlled by regulating the amount of an emulsifier. As the size increases, the CNDs exhibit blue‐shifted photoluminescence (PL) or so‐called an inverse PL shift. Using time‐correlated single photon counting, ultraviolet photoelectron spectroscopy, and low‐temperature PL measurements, it is revealed that the CNDs are composed of sp2 clusters with certain energy gaps and their oleylamine ligands act as auxochromes to reduce the energy gaps. This insight can provide a plausible explanation on the origin of the inverse PL shift which has been debatable over a past decade. To explore the potential of the CNDs as photoactive materials, several prototypes of CND‐based optoelectronic devices, including multicolored light‐emitting diodes and air‐stable organic solar cells, are demonstrated. This study could shed light on future applications of the CNDs and further expedite the development of other related fields.
Lithium-based ionic liquids as novel lubricant additives for multiply alkylated cyclopentanes (MACs)
Authors: Song Zenghong , Liang Yongmin , Fan Mingjin , Zhou Feng , Liu Weimin
Published: September 2013

Two lithium-based ionic liquids (ILs, L-C3N3, and L-P3N3) were synthesized and evaluated as novel lubricant additives for multiply alkylated cyclopentanes (MACs). They were found to be approximately 1.0% soluble in MACs at room temperature (RT), whereas traditional ILs, such as 1-ethyl-3-methylimidazolium tetrafluoroborate (L-B102), 1-hexyl-3-methylimidazolium hexafluorophosphate (L-P106), and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (L-F102), could not be dissolved in this base oil. Friction tests indicated that these ILs exhibit excellent friction-reducing and anti-wear properties both at RT and at 100 °C. They can improve the tribological properties of MACs at RT to a greater extent than the commonly used lubricant zinc dialkyldithiophosphate (T204), even at a concentration of 0.1%. The load ramp test showed that MACs with L-C3N3 and L-P3N3 also exhibit high load-carrying capabilities. Scanning electron microscope (SEM) and X-ray photoelectron spectrometer (XPS) results indicated that physical adsorption and complex tribochemical reactions occurred between the ILs and metal surfaces during the sliding process, thereby forming a surface protective film that significantly contributed to the excellent tribological properties of the new ILs.
Atomistic simulations of friction at an ice-ice interface
Authors: Samadashvili N. , Reischl B. , Hynninen T. , Ala-Nissilä T. , Foster A. S.
Published: September 2013

Even though the slipperiness of ice is important both technologically and environmentally and often experienced in everyday life, the nanoscale processes determining ice friction are still unclear. We study the friction of a smooth ice-ice interface using atomistic simulations, and especially consider the effects of temperature, load, and sliding velocity. At this scale, frictional behavior is seen to be determined by the lubricating effect of a liquid premelt layer between the sliding ice sheets. In general, increasing temperature or load leads to a thicker lubricating layer and lower friction, while increasing the sliding velocity increases friction due to viscous shear.
Petroleum Pipelines
Authors: Chanda Sanjoy
Published: September 2013

Petroleum pipelines ensure the sustained availability of petroleum products all across the country. Pipelines transport petroleum products in a safe and efficient manner from refineries to demand areas. They also transport crude oil from import terminals as well as domestic sources to the inland refineries. India, being a developing nation, has a large network of petroleum pipelines. Economic growth and expansion of infrastructure in this country offer opportunities to better utilize the existing pipeline network. The construction of new pipelines extends this network further.

 This book introduces readers to the field of petroleum pipelines, describes the salient features of a pipeline and discusses how this system is superior to other modes of petroleum transportation. It provides a brief account on different types of fluids transported through pipelines and highlights their properties that affect pipeline design. The book details the actual design of a pipeline  from route selection, hydraulic, mechanical and other aspects of design and engineering. It also describes the operation and maintenance procedures required in the pipeline system to run at a level of efficiency equivalent to its design efficiency.

 Key features
  Covers design and engineering of pipelines
  Discusses deployment of personnel and construction equipment
  Deals with pre-commissioning and commissioning of pipelines
  Examines corrosion of steel pipelines running underground
  Describes in detail the operation and maintenance procedures
A Course of Modern Analysis
Authors: Whittaker E. T. , Watson G. N.
Published: September 2013

This classic text is known to and used by thousands of mathematicians and students of mathematics throughout the world. It gives an introduction to the general theory of infinite processes and of analytic functions together with an account of the principal transcendental functions.
The Cambridge Songs
Authors: Breul Karl
Published: September 2013

The Cambridge Songs are preserved - many of them uniquely - in a famous eleventh-century manuscript held in Cambridge University Library. Composed in Germany, mostly in Latin but with some vernacular sections, these lyrics are most notable for the variety they display in both genre and form. As one of the earliest examples of medieval secular song-writing they are a key part of the canon of European literature. This 1915 edition was the first to reproduce the complete text with facing-page transcriptions. Karl Breul, originally from Berlin, became the first university lecturer in German in 1884, and remained the most eminent Germanist at Cambridge until his death in 1932. His edition continues to be of value to medievalists today both as a source for the study of these remarkable poems and as a record of Breul's achievement in scholarship and palaeography.
The Malay Archipelago
Authors: Wallace Alfred Russel
Published: September 2013

Alfred Russel Wallace (1823–1913) was a British naturalist best remembered as the co-discoverer, with Darwin, of natural selection. His extensive fieldwork and advocacy of the theory of evolution led to him being considered one of the nineteenth century's foremost biologists. These volumes, first published in 1869, contain Wallace's acclaimed and highly influential account of extensive fieldwork he undertook in modern Indonesia, Malaysia and New Guinea between 1854 and 1862. Wallace describes his travels around the island groups, depicting the unusual animals and insects he encountered and providing ethnographic descriptions of the indigenous peoples. Wallace's analysis of biogeographic patterns in Indonesia (later termed the Wallace Line) profoundly influenced contemporary and later evolutionary and geological thought concerning both Indonesia and other areas of the world where similar patterns were found. Volume 1 covers the islands of Indonesia and Malaysia.
The Opening Up of International Organizations
Authors: Tallberg Jonas , Sommerer Thomas , Squatrito Theresa , Jönsson Christer
Published: September 2013

Once the exclusive preserve of member states, international organizations have become increasingly open in recent decades. Now virtually all international organizations at some level involve NGOs, business actors and scientific experts in policy-making. This book offers the first systematic and comprehensive analysis of this development. Combining statistical analysis and in-depth case studies, it maps and explains the openness of international organizations across issue areas, policy functions and world regions from 1950 to 2010. Addressing the question of where, how and why international organizations offer transnational actors access to global policy-making, this book has implications for critical issues in world politics. When do states share authority with private actors? What drives the design of international organizations? How do activists and businesses influence global politics? Is civil society involvement a solution to democratic deficits in global governance?
Musculoskeletal Cytohistology
Authors: Layfield Lester J. , Bedrossian Carlos W. , Crim Julia R. , Palombini Lucio
Published: September 2013

Each volume in this richly illustrated series, sponsored by the Papanicolaou Society of Cytopathology, provides an organ-based approach to the cytological and histological diagnosis of small tissue samples. Benign, pre-malignant and malignant entities are presented in a well-organized and standardized format, with high-resolution color photomicrographs, tables, tabulated specific morphologic criteria and appropriate ancillary testing algorithms. Example vignettes allow the reader to assimilate the diagnostic principles in a case-based format. This volume describes the cytologic, small core biopsy, immunohistochemical and molecular diagnostic features of musculoskeletal lesions. It provides the cytopathologist and histopathologist with a comprehensive survey of diagnostic approaches and diagnostic features for benign and malignant lesions. Each chapter contains a detailed summary of differential diagnostic features, supported by high-quality images and case studies. The print edition includes a CD-ROM offering all images in a downloadable format. With over 500 photomicrographs, this is an important resource for practising pathologists and residents in pathology.
General Todleben's History of the Defence of Sebastopol, 1854–5
Authors: Russell William Howard
Published: September 2013

The journalist William Howard Russell (1820–1907) is sometimes regarded as being the first war correspondent, and his reports from the conflict in the Crimea are also credited with being a cause of reforms made to the British military system. This 1865 book began as a review in The Times of the five-volume work of General Eduard Todleben (or Totleben), the military engineer and Russian Army General, whose work in creating and continually adapting the land defences of Sevastopol in 1854–5 made him a hero and enabled the fortress to hold out against British bombardment for a whole year. Russell added extracts from the original book to his review, and enlarged his commentary on the Russian text, producing a thorough and accurate synthesis, but always highlighting the central importance of the Russian work to any student of the history of the Sevastopol siege.
MIXING FOR PROGRESSIONS IN NONABELIAN GROUPS
Authors: TAO TERENCE
Published: September 2013

We study the mixing properties of progressions $(x, xg, x{g}^{2} )$, $(x, xg, x{g}^{2} , x{g}^{3} )$ of length three and four in a model class of finite nonabelian groups, namely the special linear groups ${\mathrm{SL} }_{d} (F)$ over a finite field $F$, with $d$ bounded. For length three progressions $(x, xg, x{g}^{2} )$, we establish a strong mixing property (with an error term that decays polynomially in the order $\vert F\vert $ of $F$), which among other things counts the number of such progressions in any given dense subset $A$ of ${\mathrm{SL} }_{d} (F)$, answering a question of Gowers for this class of groups. For length four progressions $(x, xg, x{g}^{2} , x{g}^{3} )$, we establish a partial result in the $d= 2$ case if the shift $g$ is restricted to be diagonalizable over $F$, although in this case we do not recover polynomial bounds in the error term. Our methods include the use of the Cauchy–Schwarz inequality, the abelian Fourier transform, the Lang–Weil bound for the number of points in an algebraic variety over a finite field, some algebraic geometry, and (in the case of length four progressions) the multidimensional Szemerédi theorem.
A multivariate spatial analysis of vowel formants in American English
Authors: Grieve Jack , Speelman Dirk , Geeraerts Dirk
Published: September 2013

This paper presents the results of a multivariate spatial analysis of thirty-eight vowel formant variables measured in 236 cities from across the contiguous United States, based on the acoustic data from theAtlas of North American English. The results of the analysis both confirm and challenge the results of theAtlas.Most notably, while the analysis identifies similar patterns as theAtlasin the West and the Southeast, the analysis finds that the Midwest and the Northeast are distinct dialect regions that are considerably stronger than the traditional Midland dialect region identified in theAtlas. The analysis also finds evidence that a vowel shift is actively shaping the language of the Western United States.
Escaping from Sodom: A Christian Jew Encounters German Antisemitism
Authors: RAILTON NICHOLAS
Published: September 2013

The article discusses the impact of antisemitism on Jewish Christians in twentieth-century Germany. The fate of one Jewish Christian from an Orthodox Jewish background, Maly Kagan, is used to highlight overarching themes. The article focuses on the impact of National Socialism on her work in a Protestant psychiatric hospital and for the London-based Hebrew Christian Testimony to Israel. Light is shed on how she survived the Holocaust, her work with displaced persons in Frankfurt after the war and her decision in 1952 to leave Germany to spend the rest of her life in Israel.
‘Wandelabendmahl’: Lutheran ‘Walking Communion’ and its Expression in Material Culture
Authors: RANGE MATTHIAS
Published: September 2013

This article discusses one specific way in which Protestant communion was, and still is, celebrated: the ‘Wandelabendmahl’, or ‘walking communion’, in which communicants receive bread and wine at the two sides of the altar, walking around it in between. After a general discussion of the ‘Wandelabendmahl’ in Lutheranism, the article examines how this rite was and is reflected in material culture, especially in today's northern Germany and southern Denmark. The rite was physically enshrined in church buildings by special furnishings at and around the altar. This study argues for a more holistic approach to sources: the inclusion of material culture in the study of religious practices allows for consideration and analysis of the experience of parishioners on a day-to-day basis. It is argued that it was by such means – visible, tangible, and to be experienced by each individual parishioner – that complex theological concepts were made accessible to congregations.
Psychiatric disorders in 22q11.2 deletion syndrome are prevalent but undertreated
Authors: Tang S. X. , Yi J. J. , Calkins M. E. , Whinna D. A. , Kohler C. G. , Souders M. C. , McDonald-McGinn D. M. , Zackai E. H. , Emanuel B. S. , Gur R. C. , Gur R. E.
Published: September 2013

Background

Chromosome 22q11.2 deletion syndrome (22q11DS) is a common genetic disorder with high rates of psychosis and other psychopathologies, but few studies discuss treatment. Our aim was to characterize the prevalence and treatment of major psychiatric illnesses in a well-characterized sample of individuals with 22q11DS.

Method

This was a cross-sectional study of 112 individuals aged 8 to 45 years with a confirmed diagnosis of 22q11DS. Each participant was administered a modified Schedule for Affective Disorders and Schizophrenia for School-Age Children (K-SADS) and the Structured Interview for Prodromal Syndromes (SIPS). Phenotypes assessed were threshold and subthreshold psychosis, depression, mania, generalized and separation anxiety, obsessions/compulsions, inattention/hyperactivity and substance use. Histories of mental health care and current psychotropic treatment were obtained.

Results

Psychopathology was common, with 79% of individuals meeting diagnostic criteria for a disorder at the time of assessment. Diagnoses of psychosis were made in 11% of cases, attenuated positive symptom syndrome (APS) in 21%, and 47% experienced significant subthreshold symptoms. Peak occurrence of psychosis risk was during adolescence (62% of those aged 12–17 years). Criteria for a mood disorder were met by 14%, for anxiety disorder 34% and for attention deficit hyperactivity disorder (ADHD) 31%. Mental health care had been received by 63% of individuals in their lifetime, but only 40% continued therapy and 39% used psychotropics. Antipsychotics were used by 42% of participants with psychosis and none of the participants with APS. Half of those at risk for psychosis were receiving no mental health care.

Conclusions

Psychopathology is common in 22q11DS but is not adequately treated or clinically followed. Particular attention should be paid to subthreshold psychotic symptoms, especially in adolescents.
Sedation for paediatric transcatheter atrial septal defect closure: comparison of two sedation protocols
Authors: Ülgey Ayşe , Bayram Adnan , Güneş Işın , Aksu Recep , Bicer Cihangir , Akin Aynur , Baykan Ali , Narin Nazmi , Boyaci Adem
Published: September 2013

Aim: This study aimed to compare the effects of dexmedetomidine–propofol and ketamine–propofol sedation on haemodynamic stability, immobility, and recovery time in children who underwent transcatheter closure of atrial septal defects. Methods: In all, 46 children scheduled for transcatheter closure of atrial septal defects (n = 46) were included. The dexmedetomidine–propofol group (n = 23) received dexmedetomidine (1 μg/kg) and propofol (1 mg/kg) for induction, followed by dexmedetomidine (0.5 μg/kg/hour) and propofol (100 μg/kg/minute) for maintenance. The ketamine–propofol group (n = 23) received ketamine (1 mg/kg) and propofol (1 mg/kg) for induction, followed by ketamine (1 mg/kg) and propofol (100 μg/kg/minute) for maintenance. Results: In all, 11 patients in the dexmedetomidine group (47.8%) and one patient (4.3%) in the ketamine group demonstrated a decrease ≥20% from the baseline in mean arterial pressure (p = 0.01). Heart rates decreased ≥20% from the baseline value in 10 patients (43.4%) in the dexmedetomidine group and three patients (13%) in the ketamine group (p = 0.047). Heart rate values were observed to be lower in the dexmedetomidine group throughout the procedure after the first 10 minutes. The number of patients requiring additional propofol was higher in the dexmedetomidine group (p = 0.01). The recovery times were similar in the two groups – 15.86 ± 6.50 minutes in the dexmedetomidine group and 19.65 ± 8.19 minutes in the ketamine group; p = 0.09. Conclusion: The ketamine–propofol combination was less likely to induce haemodynamic instability, with no significant change in recovery times, compared with the dexmedetomidine–propofol combination. The ketamine–propofol combination provided good conditions for the intervention.
Probing the Chemical and Electronic Properties of Individual Nanoparticles by Spatially-Resolved EELS
Authors: Gloter Alexandre , Stéphan Odile , Zobelli Alberto , Ewels Christopher , Tencé Marcel , Douiri Abdel , Colliex Christian
Published: September 2013

Extended abstract of a paper presented at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, August 1–5, 2004.
SEM Characterization in Al-C-Al2O3 Composites Produced by Stir Casting.
Authors: Flores-Zamora M. Isabel , Segura-Cedillo Ismael , Santos-Beltrán Audel , Estrada-Guel Ivanovich , Barajas Villaruel Juan Ignacio , Martínez-Sánchez Roberto
Published: September 2013

Extended abstract of a paper presented at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, August 1–5, 2004.
Mechanisms of Hyphal Tip Growth and Morphogenesis in the Filamentous Fungus Neurospora crassa
Authors: Uchida Maho , Bartnicki-García Solomon , Roberson Robert W.
Published: September 2013

Extended abstract of a paper presented at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, August 1–5, 2004.
In SituTEM Study of Catalytic Nanoparticle Reactions in Atmospheric Pressure Gas Environment
Authors: Xin Huolin L. , Niu Kaiyang , Alsem Daan Hein , Zheng Haimei
Published: September 2013

The understanding of solid–gas interactions has been greatly advanced over the past decade on account of the availability of high-resolution transmission electron microscopes (TEMs) equipped with differentially pumped environmental cells. The operational pressures in these differentially pumped environmental TEM (DP-ETEM) instruments are generally limited up to 20 mbar. Yet, many industrial catalytic reactions are operated at pressures equal or higher than 1 bar—50 times higher than that in the DP-ETEM. This poses limitations forin situstudy of gas reactions through ETEM and advances are needed to extendin situTEM study of gas reactions to the higher pressure range. Here, we present a first series of experiments using a gas flow membrane cell TEM holder that allows a pressure up to 4 bar. The built-in membrane heaters enable reactions at a temperature of 95–400°C with flowing reactive gases. We demonstrate that, using a conventional thermionic TEM, 2 Å atomic fringes can be resolved with the presence of 1 bar O2gases in an environmental cell and we show real-time observation of the Kirkendall effect during oxidation of cobalt nanocatalysts.
On the catalytic mechanism of dimeric dUTPases
Authors: Hemsworth Glyn R. , González-Pacanowska Dolores , Wilson Keith S.
Published: September 2013

The Tritryps Trypanosoma brucei, Trypanosoma cruzi and Leishmania donovani are responsible for great morbidity and mortality in developing countries. Their dimeric dUTPases are members of the all-α NTP pyrophosphohydrolase family and represent promising drug targets due to their essential nature and markedly different structural and biochemical properties compared with the trimeric human enzyme. In the present paper we describe the structure of the T. brucei enzyme in open and closed conformations. Furthermore, we probe the reaction mechanism through the binding of transition state mimics both in solution and in the crystal. 31P-NMR and tryptophan fluorescence quenching in the presence of AlF3 and MgF3− identified which phosphate is subject to nucleophilic attack by a water molecule. The structures in complex with two transition state analogues confirm that the nucleophilic attack occurs on the β-phosphate in contrast with the α-phosphate in the trimeric enzymes. These results establish the structural basis of catalysis of these important housekeeping enzymes and has ramifications for the wider all-α NTP pyrophosphohydrolase family.
Quasiclassical dynamics for the H + HS abstraction and exchange reactions on the 3A″ and the 3A′ states
Authors: Duan Zhi Xin , Li Wen Liang , Xu Wen Wu , Lv Shuang Jiang
Published: September 2013

A detailed quasiclassical trajectory study of the H + HS reaction yielding an exchange (H + HS) and an abstraction (H2 + S) channel has been performed by employing the new triplet 3A″ and 3A′ surfaces developed by our group. The cross sections for both channels are presented and found to be in good agreement with previous quantum wave packet results. The thermal rate coeﬃcients for abstraction channel at the temperature between 200 and 1000 K have been evaluated by averaging over a Boltzmann distribution of rotational states and compared with the available experimental values. It is found that the thermal rate coeﬃcients exhibit a conventional Arrhenius-type dependence on temperature, which agrees well with the experimental data. Average fractions, vibration and rotation distributions of the products H2 and HS at different collision energies have been also fully investigated. Furthermore, influence of the collision energy on the total and product-state-resolved differential cross sections (DCSs) for both channels are calculated and discussed. Some observations on the mechanism of the title reaction have been made; in particular it was discovered that reactive collisions along the collinear pathway cause the H2 product to scatter backward, while the reactive collisions with large impact parameters b, which are favored deviating from the minimum energy path, produced mainly forward scattering. For the exchange channel, the discrepancies in the DCS are also distinguished through an analysis of individual trajectories and found a double microscopic mechanism, migration or non-migration. The state-to-state DCSs provide a global perspective of the reaction mechanisms and their contribution to the final product internal energy states. The theoretical findings are discussed and compared with a kinematic constraint model.
Trimer effects in fragment molecular orbital-linear combination of molecular orbitals calculation of one-electron orbitals for biomolecules
Authors: Kobori Tomoki , Sodeyama Keitaro , Otsuka Takao , Tateyama Yoshitaka , Tsuneyuki Shinji
Published: September 2013

The fragment molecular orbital (FMO)-linear combination of molecular orbitals (LCMO) method incorporates as an efficient post-process calculation of one-electron orbitals of the whole system after the FMO total energy calculation. A straightforward way to increase the accuracy is inclusion of the trimer effect. Here, we derive a comprehensive formulation called the FMO3-LCMO method. To keep the computational costs of the trimer term low enough, we use a matrix-size reduction technique. We evaluated the accuracy and efficiency of the FMO3-LCMO scheme in model biological systems (alanine oligomer and chignolin). The results show that delocalized electronic orbitals with covalent and hydrogen bonds are better described at the trimer level, and the FMO3-LCMO method is applicable to quantitative evaluations of a wide range of frontier orbitals in large biosystems.
An energy-filtering device coupled to a quadrupole mass spectrometer for soft-landing molecular ions on surfaces with controlled energy
Authors: Bodin A. , Laloo R. , Abeilhou P. , Guiraud L. , Gauthier S. , Martrou D.
Published: September 2013

We have developed an energy-filtering device coupled to a quadrupole mass spectrometer to deposit ionized molecules on surfaces with controlled energy in ultra high vacuum environment. Extensive numerical simulations as well as direct measurements show that the ion beam flying out of a quadrupole exhibits a high-energy tail decreasing slowly up to several hundred eV. This energy distribution renders impossible any direct soft-landing deposition of molecular ions. To remove this high-energy tail by energy filtering, a 127° electrostatic sector and a specific triplet lenses were designed and added after the last quadrupole of a triple quadrupole mass spectrometer. The results obtained with this energy-filtering device show clearly the elimination of the high-energy tail. The ion beam that impinges on the sample surface satisfies now the soft-landing criterion for molecular ions, opening new research opportunities in the numerous scientific domains involving charges adsorbed on insulating surfaces.
Note: Pneumatically actuated and kinematically positioned optical mounts compatible with laser-cooling experiments
Authors: Brown Roger C. , Olmschenk S. , Wu Saijun , Dyckovsky A. M. , Wyllie R. , Porto J. V.
Published: September 2013

We present two complementary designs of pneumatically actuated and kinematically positioned optics mounts: one designed for vertical mounting and translation, the other designed for horizontal mounting and translation. The design and measured stability make these mounts well-suited to experiments with laser-cooled atoms.
Temperature-sensitive colloidal phase behavior induced by critical Casimir forces
Authors: Dang Minh Triet , Verde Ana Vila , Nguyen Van Duc , Bolhuis Peter G. , Schall Peter
Published: September 2013

We report Monte Carlo simulations of phase behavior of colloidal suspensions with near-critical binary solvents using effective pair potentials from experiments. At off-critical solvent composition, the calculated phase diagram agrees well with measurements of the experimental system, indicating that many-body effects are limited. Close to the critical composition, however, agreement between experiment and simulation becomes poorer, signaling the increased importance of many-body effects. Both at and off the critical solvent concentration, the colloidal phase diagram is qualitatively similar to those of molecular systems and obeys the principle of corresponding states with one striking difference: it occurs in a narrow temperature interval of <1 °C below the solvent phase separation temperature.
Formation and properties of iron-based magnetic superhalogens: A theoretical study
Authors: Ding Li-Ping , Kuang Xiao-Yu , Shao Peng , Zhong Ming-Min , Zhao Ya-Ru
Published: September 2013

In order to explore new magnetic superhalogens, we have systematically investigated the structures, electrophilic properties, stabilities, magnetic properties, and fragmentation channels of neutral and anionic FemFn (m = 1, 2; n = 1–7) clusters using density functional theory. Our results show that a maximum of six F atoms can be bound atomically to one Fe atom, and the Fe-Fe bonding is not preferred in Fe2Fn0/− clusters. The computed electron affinities (EAs) indicate that FeFn with n ≥ 3 are superhalogens, while Fe2Fn can be classified as superhalogens for n ≥ 5. To further understand their superhalogen characteristic, the natural population analysis charge distribution and the HOMOs of anionic clusters were also analyzed. When the extra negative charge and the content of HOMO are mainly located on F atoms, the clusters could be classified as superhalogens with EAs substantially surpass that of Cl. By calculating the binding energies per atom and the HOMO-LUMO gaps, FeF3, FeF4−, Fe2F4, Fe2F5−, and Fe2F7− clusters were found to have higher stabilities, corresponding to the Fe atoms that are attained at their favorite +2 and +3 oxidation states. Furthermore, we also predicted the most preferred fragmentation channel and product for all the ground state clusters. Even more striking is the fact that both neutral and anionic FemFn (m = 1, 2; n = 1–7) clusters carry large magnetic moments which mainly come from 3d orbital of iron atom.
An electrification mechanism of sand grains based on the diffuse double layer and Hertz contact theory
Authors: Xie Li , Han Kui , Ma Yanping , Zhou Jùn
Published: September 2013

The electrification of sand grains lifting off from sand bed is investigated experimentally. It was found that sand grains were able to carry charges, which is comparable in magnitude with the experimental results and is related to grain sizes, pH of soil, relative humidity, and electric field. Based on the theory of diffuse double layer (DDL) and Hertz contact theory, an electrification mechanism due to the break of DDLs of sand grains is presented and a formula which takes environmental conditions and grain parameters into consideration is obtained to calculate the charge-mass ratio of lift-off sand grains.
Vacuum chamber-free centrifuge with magnetic bearings
Authors: Park Cheol Hoon , Kim Soohyun , Kim Kyung-Soo
Published: September 2013

Centrifuges are devices that separate particles of different densities and sizes through the application of a centrifugal force. If a centrifuge could be operated under atmospheric conditions, all vacuum-related components such as the vacuum chamber, vacuum pump, diffusion pump, and sealing could be removed from a conventional centrifuge system. The design and manufacturing procedure for centrifuges could then be greatly simplified to facilitate the production of lightweight centrifuge systems of smaller volume. Furthermore, the maintenance costs incurred owing to wear and tear due to conventional ball bearings would be eliminated. In this study, we describe a novel vacuum chamber-free centrifuge supported by magnetic bearings. We demonstrate the feasibility of the vacuum chamber-free centrifuge by presenting experimental results that verify its high-speed support capability and motoring power capacity.
Charge carrier dynamics in organic semiconductors and their donor-acceptor composites: Numerical modeling of time-resolved photocurrent
Authors: Johnson Brian , Kendrick Mark J. , Ostroverkhova Oksana
Published: September 2013

We present a model that describes nanosecond (ns) time-scale photocurrent dynamics in functionalized anthradithiophene (ADT) films and ADT-based donor-acceptor (D/A) composites. By fitting numerically simulated photocurrents to experimental data, we quantify contributions of multiple pathways of charge carrier photogeneration to the photocurrent, as well as extract parameters that characterize charge transport (CT) in organic films including charge carrier mobilities, trap densities, hole trap depth, and trapping and recombination rates. In pristine ADT films, simulations revealed two competing charge photogeneration pathways: fast, occurring on picosecond (ps) or sub-ps time scales with efficiencies below 10%, and slow, which proceeds at the time scale of tens of nanoseconds, with efficiencies of about 11%–12%, at the applied electric fields of 40–80 kV/cm. The relative contribution of these pathways to the photocurrent was electric field dependent, with the contribution of the fast process increasing with applied electric field. However, the total charge photogeneration efficiency was weakly electric field dependent exhibiting values of 14%–20% of the absorbed photons. The remaining 80%–86% of the photoexcitation did not contribute to charge carrier generation at these time scales. In ADT-based D/A composites with 2 wt.% acceptor concentration, an additional pathway of charge photogeneration that proceeds via CT exciton dissociation contributed to the total charge photogeneration. In the composite with the functionalized pentacene (Pn) acceptor, which exhibits strong exciplex emission from a tightly bound D/A CT exciton, the contribution of the CT state to charge generation was small, ∼8%–12% of the total number of photogenerated charge carriers, dependent on the electric field. In contrast, in the composite with PCBM acceptor, the CT state contributed about a half of all photogenerated charge carriers. In both D/A composites, the charge carrier mobilities were reduced and trap densities and average trap depths were increased, as compared to a pristine ADT donor film. A considerably slower recombination of free holes with trapped electrons was found in the composite with the PCBM acceptor, which led to slower decays of the transient photocurrent and considerably higher charge retention, as compared to a pristine ADT donor film and the composite with the functionalized Pn acceptor.
Enhanced photoconductivity of 3C-SiC by Al/N codoping
Authors: Dou Yan-Kun , Li Jing-Bo , Jin Hai-Bo , Fang Xiao-Yong , Cao Mao-Sheng
Published: September 2013

In order to enhance the photoconductivity of 3C-SiC by high Al doping, the Al/N codoping has been investigated using the first principles calculation. Several structural models were constructed, i.e., Al1/N, Al2/N, Al3/N, and Al4/N. Structural stability and electronic property of Al/N codoped 3C-SiC with different models were studied. It is found that the adjacent pair of Al and N in 3C-SiC is energetically favorable, and the structure of Al/N codoped 3C-SiC is more stable than that of the mono Al doped 3C-SiC. The results indicate that the N incorporation facilitates the substitution of Al for Si in 3C-SiC. The mono doping of Al can cause the band gap decrease by 82 meV. However, the codoping of Al and N can further narrow the band gap by 167 meV. Photoconductivity calculation shows the photoconductivity of the Al/N codoped 3C-SiC is higher in the range from near infrared to ultraviolet wavelength in comparison with the intrinsic 3C-SiC. The calculated intrinsic absorption edge of Al/N codoped 3C-SiC shows a red-shift in ultraviolet region with respect to that of Al doped 3C-SiC. The electron density difference of Al/N codoped 3C-SiC indicates the bond between Al and C has stronger covalent characteristics than that between Al and N. The calculations suggest the Al/N codoped 3C-SiC semiconductor as a promising material for device applications in modern electronics.
Low-temperature synthesis of K0.5FeF3 with tunable exchange bias
Authors: Xu Qiao-Ru , Liu Yang , Zheng Yu-Di , Rui Wenbin , Sheng Yan , Shen Xuan , Du Jun , Xu Mingxiang , Dong Shuai , Wu Di , Xu Qingyu
Published: September 2013

Fluorides K0.5FeF3 with tetragonal tungsten bronze structure have been fabricated by solid state reaction at low sintering temperature in the range between 150 °C and 400 °C with the assistance of crystal water during the grinding and sintering processes. Unusual magnetic properties have been observed, including positive exchange bias field (HE) with negative vertical magnetization shift (Mshift), and smaller field cooling (FC) magnetization than the zero field cooling one below 53 K. The results are explained by a core-shell structure consisting of antiferromagnetic core and spin glass (SG) shell with antiferromagnetic interfacial coupling between the pinned interface spins and the SG shell spins. The sign of HE and Mshift can be changed by increasing the cooling field in the FC process, which is attributed to the competition between the antiferromagnetic interfacial coupling and the Zeeman energy of magnetization of the SG shell.
Nitrogen-containing point defects in multi-crystalline Si solar-cell materials
Authors: Zhang Haoxiang , Stavola Michael , Seacrist Mike
Published: September 2013

The multi-crystalline Si used to fabricate solar cells contains nitrogen, with a concentration typically in the mid-1015 cm−3 range that was introduced by the Si3N4 liner of the crucible used for ingot growth. Low temperature infrared spectroscopy has been used to identify and determine the concentrations of the nitrogen-containing point defects in multi-crystalline samples with a range of nitrogen and oxygen concentrations. We find that the dominant nitrogen centers in multicrystalline Si are the NN and NNOn complexes that are well-known from studies of monocrystalline Si. In as-grown, multi-crystalline Si with an oxygen content of [O] = 3.2 × 1017 cm−3, 44% of the nitrogen was found to be present as NN-On complexes. We also found that near 1 × 1014 cm−3 NOn shallow donors can be present. The concentrations of nitrogen centers that also contain oxygen depend strongly on the concentration of oxygen in the multi-crystalline Si substrate.
Giant Seebeck coefficient of the graphene/h-BN superlattices
Authors: Yokomizo Yushi , Nakamura Jun
Published: September 2013

The electronic structures and Seebeck coefficients of the graphene/h-BN superlattices which consist of zigzag graphene nanoribbons (ZGNRs) and zigzag BN nanoribbons (ZBNNRs) have been investigated using ab initio calculations based on the density functional theory. It has been shown that a ZGNR/ZBNNR marks up to 20 times larger in the Seebeck coefficient than graphene. The Seebeck coefficients of the superlattices increase with decreasing width of the constituent ZGNR. It has been revealed that the giant Seebeck coefficients of the superlattices stem from the so-called pudding mold band with a finite energy gap.
The effects of thin capping layers between quantum wells and barriers on the quantum efficiency enhancement in InGaN-based light emitting diodes
Authors: Li X. , Milton Yeh Yea-Chuan , Yang S. L. , Chen J. C. , Chuang Chih-Li , El-Ghoroury Hussein S.
Published: September 2013

We discovered that adding H2 to the carrier gas in GaN barrier growth improved the light emitting diode (LED) peak quantum efficiency and shifted the efficiency maxima toward lower currents (∼20 mA). This implies that the Shockley–Read–Hall nonradiative process can be suppressed via the introduction of combination carrier gas (H2/N2) during barrier growth. Further, 1–2 nm thick Al-In-Ga-N alloys were adopted as capping layers to circumvent H2 etching effect during growth interruption. It was then revealed that quantum efficiency was effectively enhanced for LEDs employed with these thin large bandgap capping layers, particularly at low injection levels. Numerical simulation suggested that the improved quantum efficiency can be ascribed to the increased electron capture rate in the active region as well as enhanced electron and hole wavefunction overlap, which correlated well with experimental results.
Potential exposure of perfluorinated compounds to Chinese in Shenyang and Yangtze River Delta areas
Authors: Lu Guo-Hui , Yang Yong-Liang , Taniyasu Sachi , Yeung Leo W. Y. , Pan Jing , Zhou Bingsheng , Lam Paul K. S. , Yamashita Nobuyoshi
Published: September 2013

Environmental contextA total of 21 perfluorinated compounds (PFCs) including PFOS were quantified in river waters, sewage, sea waters, shallow ground waters as well as fish and domestic poultry, focussed on the main river basins in Shenyang and the Yangtze River Delta areas, China. The distribution characteristics of PFCs in the aquatic environment and evaluation of the potential risk for human health via the diet of fish was discussed. Comprehensive research was carried out using the world leading knowledge about PFOS-related chemicals in AIST, Japan to enable reliable evaluation of PFOS risk in Chinese environments, supported by ISO25101.
AbstractA total of 21 perfluorinated compounds (PFCs) were quantified in water and biota samples collected from Shenyang in North-east China and the Yangtze River Delta area in East China. The human health risk owing to intake of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) via fish and domestic poultry dietary was evaluated. The total PFC concentration (∑PFC) in water samples from the rivers in Shenyang averaged 5.32 ng L–1, with PFOS and PFOA as the predominant compounds. The urban sewage could be the source of PFOS and perfluorohexane sulfonate (PFHxS) in the surface waters. The total PFCs in water samples from the Yangtze River Delta area ranged from 42.4 to 170 ng L–1. The highest concentrations of most PFCs were observed in waters from the Shanghai section of the Yangtze River. In the biota samples, PFOS and PFUnDA (perfluoroundecanoic acid) were the most abundant. The acceptable daily intake (ADI) and hazard ratio (HR) values for PFOS and PFOA intake through the diet of fish and poultry in the studied areas were calculated, and showed that the HR values for PFOS and PFOA are all less than 1.0 for both the areas.
Analysis of global host gene expression during the primary phase of the Arabidopsis thaliana–Plasmodiophora brassicae interaction
Authors: Agarwal Arati , Kaul Vijay , Faggian Robert , Rookes James E. , Ludwig-Müller Jutta , Cahill David M.
Published: September 2013

Microarray analysis was used to investigate changes in host gene expression during the primary stages of the interaction between the susceptible plant Arabidopsis thaliana (L.) Heynh ecotype Col-0 and the biotrophic pathogen Plasmodiophora brassicae Woronin. Analyses were conducted at 4, 7 and 10 days after inoculation (DAI) and revealed significant induction or suppression of a relatively low number of genes in a range of functional categories. At 4 DAI, there was induced expression of several genes known to be critical for pathogen recognition and signal transduction in other resistant host–pathogen interactions. As the pathogen further colonised root tissue and progressed through the primary plasmodium stage to production of zoosporangia at 7 and 10 DAI, respectively, fewer genes showed changes in expression. The microarray results were validated by examining a subset of induced genes at 4 DAI by quantitative real-time reverse transcriptase PCR (RT-qPCR) analysis all of which correlated positively with the microarray data. The two A. thaliana mutants jar1 and coiI tested were found to be susceptible to P. brassicae. The involvement of defence-related hormones in the interaction was further investigated and the findings indicate that addition of salicylic acid can suppress clubroot disease in A. thaliana plants.