bluuebunny/crossref_metadata_2025 huggingface dataset:
Vitamin K metabolism: Current knowledge and future research
Authors: Card David J. , Gorska Renata , Cutler Jacky , Harrington Dominic J.
Published: December 2013

Vitamin K is an essential fat‐soluble micronutrient that is required for the post‐translational γ‐carboxylation of specific glutamic acid residues in hepatic and extra‐hepatic proteins involved in blood coagulation and preventing cartilage and vasculature calcification. In humans, sources of vitamin K are derived from plants as phylloquinone and bacteria as the menaquinones. Menadione is a synthetic product used as a pharmaceutical but also represents an intermediate in the tissue‐specific conversion of vitamin K to menaquinone‐4, which preferentially resides in tissues such as brain. Research into vitamin K metabolism is essential for the understanding of vitamin K biology in health and disease. Progress in this area, driven by knowledge of vitamin K and the availability of markers of vitamin K status, has already proved beneficial in many areas of medicine and further opportunities present themselves. Areas of interest discussed in this review include prophylactic administration of vitamin K1 in term and preterm neonates, interactions between vitamins K and E, the industrial conversion of vitamin K to dihydro‐vitamin K in foods, tissue‐specific conversion of vitamin K to menaquinone‐4, the biological activity of the five and seven carbon metabolites of vitamin K and circadian variations.
Leveraging countermeasures as a service for VoIP security in the cloud
Authors: Dabbebi Oussema , Badonnel Remi , Festor Olivier
Published: December 2013

The emergence of cloud computing is contributing to the integration of multiple services, in particular VoIP services. While the cloud has recently been used for performing security attacks targeting IP telephony, it also provides new opportunities for supporting the security of this service. In that context, we propose a risk management strategy for VoIP cloud based on security countermeasures that may be outsourced as services. We present the architecture of our solution and its components in the context of services implementing the SIP protocol. We describe the mathematical modelling supporting our approach and detail different treatment strategies for the application of countermeasures. Finally, we quantify the benefits and limits of these strategies based on extensive simulation results. When a countermeasure fails, these strategies allow us to maintain the risk level low at an additional cost of up to 7%, or to accept an additional risk of up to 12%. They can also be combined to obtain a trade‐off between cost and performance. Copyright © 2013 John Wiley & Sons, Ltd.
High frequency of BRAFV600E mutations in ameloblastoma
Authors: Kurppa Kari J , Catón Javier , Morgan Peter R , Ristimäki Ari , Ruhin Blandine , Kellokoski Jari , Elenius Klaus , Heikinheimo Kristiina
Published: December 2013

Ameloblastoma is a benign but locally infiltrative odontogenic neoplasm. Although ameloblastomas rarely metastasise, recurrences together with radical surgery often result in facial deformity and significant morbidity. Development of non‐invasive therapies has been precluded by a lack of understanding of the molecular background of ameloblastoma pathogenesis. When addressing the role of ERBB receptors as potential new targets for ameloblastoma, we discovered significant EGFR over‐expression in clinical samples using real‐time RT–PCR, but observed variable sensitivity of novel primary ameloblastoma cells to EGFR‐targeted drugs in vitro. In the quest for mutations downstream of EGFR that could explain this apparent discrepancy, Sanger sequencing revealed an oncogenic BRAF V600E mutation in the cell line resistant to EGFR inhibition. Further analysis of the clinical samples by Sanger sequencing and BRAF V600E‐specific immunohistochemistry demonstrated a high frequency of BRAF V600E mutations (15 of 24 samples, 63%). These data provide novel insight into the poorly understood molecular pathogenesis of ameloblastoma and offer a rationale to test drugs targeting EGFR or mutant BRAF as novel therapies for ameloblastoma. Published by John Wiley & Sons, Ltd. www.pathsoc.org.uk
The economic burden of caregiving on families of children and adolescents with cancer: A population‐based assessment
Authors: Pagano Eva , Baldi Ileana , Mosso Maria Luisa , di Montezemolo Luca Cordero , Fagioli Franca , Pastore Guido , Merletti Franco
Published: December 2013

Background

Childhood cancer represents a relevant economic burden on families. The preferred tool to investigate family expenditure is the retrospective questionnaire, which is subject to recall errors and selection bias. Therefore, in the present study the economic burden of caregiving on families of children and adolescents (0–19 years of age) with cancer was analysed using administrative data as an alternative to retrospective questionnaires.

Procedure

Incident cases of cancer diagnosed in children and adolescents in 2000–2005 (N = 917) were identified from the Piedmont Childhood Cancer Registry and linked to available administrative databases to identify episodes of care during the 3 years after diagnosis (N = 13,433). The opportunity cost of informal caregiving was estimated as the value of the time spent by one of the parents, and was assumed to be equal to the number of days during which the child received inpatient care, day‐care or outpatient radiotherapy. Factors affecting the level of economic burden of caregiving on families were analysed in a multivariable model.

Results

The economic burden of caregiving increased when care was supplied at the Regional Referral Centre, or when treatment complexity was high. Families with younger children had a higher level of economic burden of caregiving. Leukaemia required a higher family commitment than any other cancer considered.

Conclusions

Estimates of the economic burden of caregiving on families of children and adolescents with cancer derived from administrative data should be considered a minimum burden. The estimated effect of the covariates is informative for healthcare decision‐makers in planning support programmes. Pediatr Blood Cancer 2014;61:1088–1093. © 2013 Wiley Periodicals, Inc.
Use of allopurinol in children with acute lymphoblastic leukemia to reduce skewed thiopurine metabolism
Authors: Brackett Julienne , Schafer Eric S. , Leung Daniel H. , Bernhardt M. Brooke
Published: December 2013

Mercaptopurine (6‐MP), a critical component of acute lymphoblastic leukemia (ALL) therapy, is metabolized to 6‐thioguanine (6‐TGN) which is responsible for its anti‐leukemic effect, and to 6‐methylmercaptopurine nucleotides (6‐MMPN/6‐MMP) which can be hepatotoxic. Some patients preferentially metabolize 6‐MP to 6‐MMPN which may increase the risk of liver injury, reduce serum levels of 6‐TGN and potentially increase the risk of relapse. The addition of allopurinol to oral 6‐MP has been shown to optimize metabolism towards 6‐TGN in patients with inflammatory bowel disease (IBD); however, this use has not been reported in patients undergoing treatment for ALL. Pediatr Blood Cancer 2014;61:1114–1117. © 2013 Wiley Periodicals, Inc.
Effects of mesoporous silica particles on the emulsion polymerization of methyl methacrylate
Authors: Zhang Fa‐Ai , Luo Ming , Chen Zheng‐Ji , Wei Zhi‐Bo , Pinnavaia Thomas J.
Published: December 2013

Rod‐like and spherical mesoporous SBA‐15 silica particles were synthesized as pure silicas and surface modified by organosilane coupling agents firstly, and then the effects of these mesoporous materials on the critical micelle concentration (CMC) of sodium dodecylsulfate (SDS), the stabilities of batch and semi‐continuous MMA emulsion polymerizations, and the molecular weights and molecular weight distributions of the polymer products were studied. The incorporation of both unmodified and silane‐modified forms of the mesoporous silica particles in the polymerization reaction increased the CMC of SDS. The presence of the unmodified mesoporous silica in the polymerization process led to instability in the batch emulsion polymerization process, as indicated by the formation of increased amounts of coagulum, and a decrease in the molecular weight of the polymer product. However, in comparison to the polymer formed in the absence of particle additives the molecular weight of the PMMA polymer increased with the amount of emulsifier and the addition of silane‐modified SBA‐15 particles, suggesting the growth of the polymer chains is facilitated at least in part by reaction in the pores of the particles. The improvement in molecular weight indicates that semi‐continuous MMA emulsion polymerization is best suited for the preparation of PMMA–mesoporous silica composites. POLYM. ENG. SCI., 54:2746–2752, 2014. © 2013 Society of Plastics Engineers
Identification of redox‐sensitive cysteines in the Arabidopsis proteome using OxiTRAQ, a quantitative redox proteomics method
Authors: Liu Pei , Zhang Huoming , Wang Hai , Xia Yiji
Published: December 2013

Cellular redox status plays a key role in mediating various physiological and developmental processes often through modulating activities of redox‐sensitive proteins. Various stresses trigger over‐production of reactive oxygen/nitrogen species which lead to oxidative modifications of redox‐sensitive proteins. Identification and characterization of redox‐sensitive proteins are important steps toward understanding molecular mechanisms of stress responses. Here, we report a high‐throughput quantitative proteomic approach termed OxiTRAQ for identifying proteins whose thiols undergo reversible oxidative modifications in Arabidopsis cells subjected to oxidative stress. In this approach, a biotinylated thiol‐reactive reagent is used for differential labeling of reduced and oxidized thiols. The biotin‐tagged peptides are affinity purified, labeled with iTRAQ reagents, and analyzed using a paralleled HCD‐CID fragmentation mode in an LTQ‐Orbitrap. With this approach, we identified 195 cysteine‐containing peptides from 179 proteins whose thiols underwent oxidative modifications in Arabidopsis cells following the treatment with hydrogen peroxide. A majority of those redox‐sensitive proteins, including several transcription factors, were not identified by previous redox proteomics studies. This approach allows identification of the specific redox‐regulated cysteine residues, and offers an effective tool for elucidation of redox proteomes.
Nanostructured hybrid material based on highly mismatched III–V nanocrystals fully embedded in silicon
Authors: Benyoucef M. , Alzoubi T. , Reithmaier J. P. , Wu M. , Trampert A.
Published: December 2013

InAs quantum dots were directly grown on (100) planar silicon surfaces and embedded in a defect‐free silicon matrix after a multi‐step silicon overgrowth and annealing process performed by molecular beam epitaxy. Detailed high‐resolution transmission electron microscope investigations allow to follow within several steps the formation process of nearly fully relaxed InAs nanocrystals embedded in a defect‐free and planar silicon layer. The lattice mismatch between InAs and Si is almost fully accommodated by closed misfit dislocation loops at the III–V silicon interface, which suppresses the generation of threading dislocations in the embedding silicon matrix.

InAs QDs embedded in defect‐free silicon.
Gridded, locally calibrated, probabilistic temperature forecasts based on ensemble model output statistics
Authors: Scheuerer M. , König G.
Published: December 2013

We propose a further refinement of the the non‐homogeneous Gaussian regression approach for temperature, which transforms the output of an ensemble prediction system into predictive Gaussian distributions at each location of interest. Model fitting is partly done within a regression framework using a penalized version of the least‐squares loss function. This is conceptually simpler than the original approach and at the same time is able to prevent overfitting. While calibration is initially performed at observation locations only, geostatistical methods are used to provide predictive distributions on the entire grid. The incorporation of land‐use information in this interpolation scheme further improves predictive performance, even though a simpler statistical model than in the original approach is used. The assessment of predictive performance and calibration is carried out with dynamical forecasts of 2 m temperatures by the COSMO‐DE‐EPS, an application of the COSMO (Consortium for Small‐scale Modeling) model system which covers Germany and neighbouring countries.
A Bayesian Analysis of Very Small Unreplicated Experiments
Authors: Aguirre‐Torres Víctor , de la Vara Román
Published: December 2013

It is not uncommon to deal with very small experiments in practice. For example, if the experiment is conducted on the production process, it is likely that only a very few experimental runs will be allowed. If testing involves the destruction of expensive experimental units, we might only have very small fractions as experimental plans. In this paper, we will consider the analysis of very small factorial experiments with only four or eight experimental runs. In addition, the methods presented here could be easily applied to larger experiments. A Daniel plot of the effects to judge significance may be useless for this type of situation. Instead, we will use different tools based on the Bayesian approach to judge significance. The first tool consists of the computation of the posterior probability that each effect is significant. The second tool is referred to in Bayesian analysis as the posterior distribution for each effect. Combining these tools with the Daniel plot gives us more elements to judge the significance of an effect. Because, in practice, the response may not necessarily be normally distributed, we will extend our approach to the generalized linear model setup. By simulation, we will show that not only in the case of discrete responses and very small experiments, the usual large sample approach for modeling generalized linear models may produce a very biased and variable estimators, but also that the Bayesian approach provides a very sensible results. Copyright © 2013 John Wiley & Sons, Ltd.
An Individuals Generalized Likelihood Ratio Control Chart for Monitoring Linear Profiles
Authors: Xu Liaosa , Peng Yiming , Reynolds Marion R.
Published: December 2013

This paper investigates a generalized likelihood ratio (GLR) control chart for detecting sustained changes in the parameters of linear profiles when individual observations are sampled. The control charts usually used for monitoring linear profiles are based on taking a sample of n observations at each sampling time point, where n is large enough that a regression model can be fitted at each sampling point using these n observations. For this sampling scenario, it has been shown that a GLR control chart has many advantages over other control chart schemes in terms of convenience of design, fast detection of process changes, and useful diagnostic aids. However, in many applications, it may not be convenient or possible to take a sample larger than n = 1. Therefore, it is desirable to develop some control chart to monitor profile data with individual observations (n = 1) at each sampling point. In this paper, we consider a GLR control chart based on individual observations and show that it has certain advantages compared with the GLR chart based on groups of observations. An important advantage of GLR control charts is that the only design parameter that needs to be specified in order to use a GLR chart is the control limit, and here, control limits for linear profiles up to eight regression coefficients are provided for convenient use by practitioners. Copyright © 2013 John Wiley & Sons, Ltd.
Comparing ion‐pairing reagents and sample dissolution solvents for ion‐pairing reversed‐phase liquid chromatography/electrospray ionization mass spectrometry analysis of oligonucleotides
Authors: Gong Lingzhi , McCullagh James S. O.
Published: December 2013

RATIONALE

A sensitive and selective liquid chromatography/mass spectrometry (LC/MS) method is essential for quality control of synthetic oligonucleotides. However, researchers are still searching for improvements to ion‐pairing reagents for ion‐pairing reversed‐phase LC/MS. This study performed a comprehensive comparison of six ion‐pairing reagents to determine their performance as mobile phase modifiers for oligonucleotide LC/MS.

METHODS

The study was performed using a Waters ultra‐performance liquid chromatography (UPLC®) system coupled to a Waters LCT premier XE ESI‐TOF mass spectrometer by using a UPLC® OST column (2.1 mm × 100 mm, 1.7µm). Buffer systems containing ion‐pairing reagents (triethylamine, tripropylamine, hexylamine, N,N‐dimethylbutylamine, dibutylamine, N,N‐diisopropylethylamine) and hexafluoro‐2‐propanol were compared by measuring the adduct ion formation, chromatographic separation, and MS signal intensity of four oligonucleotides (10mer to 40mer). The effect of dissolution solvents on MS signal intensity and adduct ion formation was also investigated.

RESULTS

Results showed that the type of dissolution solvent can have a signficiant impact on adduct ion formation with oligonucleotides. Results also showed that the maximum separation for small, medium and large oligonucleotides occured when using tripropylamine, N,N‐dimethylbutylamine, and dibutylamine, respectively. However, on average 15 mM hexylamine and 50 mM hexafluoro‐2‐propanol provided the best chromtatographic performance (resolution values: 14.1 ± 0.34, 11.0 ± 0.17, and 6.4 ± 0.11 for the pairs of oligonucleotides T10 & T15, T15 & T25, and T25 & T40, respectively (3 replicates)).

CONCLUSIONS

The impact of dissolution solvent on the MS signal of oligonucleotides depends on the type of ion‐pairing reagent. Buffer combining 15 mM hexylamine and 50 mM hexafluoro‐2‐propanol produced the highest overall performance for oligonucleotides (10mer to 40mer) with respect to chromatographic resolution and mass detection. Copyright © 2013 John Wiley & Sons, Ltd.
Characterizing changes in snow crab (Chionoecetes opilio) cryptocyanin protein during molting using matrix‐assisted laser desorption/ionization mass spectrometry and tandem mass spectrometry
Authors: Demian Wael L. L. , Jahouh Farid , Stansbury Don , Randell Edward , Brown Robert J. , Banoub Joseph H.
Published: December 2013

RATIONALE

We report the matrix‐assisted laser desorption/ionization mass spectrometric (MALDI‐MS) characterization of the cryptocyanin proteins of the juvenileChionoecetes opiliocrabs during their molting and non‐molting phases. In order to assess the structural cryptocyanin protein differences between the molting and non‐molting phases, the obtained peptides were sequenced by MALDI low‐energy collision‐induced dissociation tandem mass spectrometry (CID‐MS/MS).

METHODS

The cryptocyanin protein was isolated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE) and analyzed by MALDI‐TOF/TOF‐MS. The purified cryptocyanin protein was sequenced, using the 'bottom‐up' approach. After tryptic digestion, the peptide mixture was analyzed by MALDI‐QqTOF‐MS/MS and the data obtained were used for the peptide mass fingerprinting (PMF) identification by means of the Mascot database.

RESULTS

It was demonstrated using MALDI‐TOF/TOF‐MS that the actual molecular weights of the non‐molting and molting cryptocyanin proteins were different; these were, respectively, 67.6 kDa and 68.1 kDa. Using low‐energy CID‐MS/MS we have sequenced the trytic peptides to monitor the differences and similarities between the cryptocyanin molecular structures during the molting and non‐molting stages.

CONCLUSIONS

We have demonstrated for the first time that the actual molecular masses of the cryptocyanin protein during the molting and non‐molting phases were different. The MALDI‐CID‐MS/MS analyses allowed the sequencing of the cryptocyanins after tryptic digestion, during the molting and non‐molting stages, and showed some similarities and staggering differences between the identified cryptocyanin peptides. Copyright © 2013 John Wiley & Sons, Ltd.
Fungal oxygen exchange between denitrification intermediates and water
Authors: Rohe Lena , Anderson Traute‐Heidi , Braker Gesche , Flessa Heinz , Giesemann Anette , Wrage‐Mönnig Nicole , Well Reinhard
Published: December 2013

RATIONALE

Fungi can contribute greatly to N2O production from denitrification. Therefore, it is important to quantify the isotopic signature of fungal N2O. The isotopic composition of N2O can be used to identify and analyze the processes of N2O production and N2O reduction. In contrast to bacteria, information about the oxygen exchange between denitrification intermediates and water during fungal denitrification is lacking, impeding the explanatory power of stable isotope methods.

METHODS

Six fungal species were anaerobically incubated with the electron acceptors nitrate or nitrite and 18O‐labeled water to determine the oxygen exchange between denitrification intermediates and water. After seven days of incubation, gas samples were analyzed for N2O isotopologues by isotope ratio mass spectrometry.

RESULTS

All the fungal species produced N2O. N2O production was greater when nitrite was the sole electron acceptor (129 to 6558 nmol N2O g dw–1 h–1) than when nitrate was the electron acceptor (6 to 47 nmol N2O g dw–1 h–1). Oxygen exchange was complete with nitrate as electron acceptor in one of five fungi and with nitrite in two of six fungi. Oxygen exchange of the other fungi varied (41 to 89 % with nitrite and 11 to 61 % with nitrate).

CONCLUSIONS

This is the first report on oxygen exchange with water during fungal denitrification. The exchange appears to be within the range previously reported for bacterial denitrification. This adds to the difficulty of differentiating N2O producing processes based on the origin of N2O‐O. However, the large oxygen exchange repeatedly observed for bacteria and now also fungi could lead to less variability in the δ18O values of N2O from soils, which could facilitate the assessment of the extent of N2O reduction. Copyright © 2013 John Wiley & Sons, Ltd.
A Collision‐resilient Flying Robot
Authors: Briod Adrien , Kornatowski Przemyslaw , Zufferey Jean‐Christophe , Floreano Dario
Published: December 2013

Flying robots that can locomote efficiently in GPS‐denied cluttered environments have many applications, such as in search and rescue scenarios. However, dealing with the high amount of obstacles inherent to such environments is a major challenge for flying vehicles. Conventional flying platforms cannot afford to collide with obstacles, as the disturbance from the impact may provoke a crash to the ground, especially when friction forces generate torques affecting the attitude of the platform. We propose a concept of resilient flying robots capable of colliding into obstacles without compromising their flight stability. Such platforms present great advantages over existing robots as they are capable of robust flight in cluttered environments without the need for complex sense and avoid strategies or three‐dimensional mapping of the environment. We propose a design comprising an inner frame equipped with conventional propulsion and stabilization systems enclosed in a protective cage that can rotate passively thanks to a three‐axis gimbal system, which reduces the impact of friction forces on the attitude of the inner frame. After addressing important design considerations thanks to a collision model and validation experiments, we present a proof‐of‐concept platform, named GimBall, capable of flying in various cluttered environments. Field experiments demonstrate the robot's ability to fly fully autonomously through a forest while experiencing multiple collisions.
Reconciling Hydropower and Environmental Water Uses in the Leishui River Basin
Authors: Ai X. S. , Sandoval‐Solis S. , Dahlke H. E. , Lane B. A.
Published: December 2013

Today's water systems require integrated water resource management to improve the water supply for conflicting water uses. This research explores alternative policies to improve the water supply for two conflicting uses, hydropower and environmental, using the Leishui River basin and Dongjiang reservoir as a case study. First, the natural flow regime prior to reservoir construction (pre‐1992) was estimated by performing a statistical analysis of 41 years of daily streamflow data (March 1952–February 1993). This natural flow regime was used as a template for proposing environmental flow (e‐flow) requirements. The post‐reservoir flow regime (post‐1992) (March 1993–February 2011) was analysed to estimate the streamflow alteration. Results show that the natural flow regime has been completely transformed; post‐1992 winter normal flows are greater, and summer flows are smaller than pre‐1992 conditions. Also, the occurrence of natural floods has been prevented. Second, a planning model was built of the current operation of the Dongjiang reservoir and used for comparison of four alternative water management policies that considered e‐flow releases from the Dongjiang reservoir. The scenarios that considered combinations of the current operational policy and e‐flow releases performed better in terms of hydropower generation than the current operation. Different volumes of e‐flow requirements were tested, and an annual e‐flow volume of 75% of the pre‐1992 hydrograph was determined to generate the most hydropower while providing for environmental water needs. Trade‐offs are essential to balance these two water management objectives, and compromises have to be made for both water uses to obtain benefits. Copyright © 2013 John Wiley & Sons, Ltd.
Unveiling the temporally contingent role of codification in alliance success
Authors: Heimeriks Koen H. , Bingham Christopher B. , Laamanen Tomi
Published: December 2013

While prior research highlights the importance of codifying alliance experience to achieve alliance success, it is unclear whether codification is equally useful in the different phases of an alliance. Based on a sample of 192 technology firms that report on over 3,400 strategic alliances, we find that in the partner selection and termination phases, reliance on codified knowledge is useful. However, in the partner management phase, reliance on codified knowledge is less beneficial and can be even negatively related to performance. Our findings have implications for the tension between flexibility and efficiency and the relationship between structure and performance. Copyright © 2013 John Wiley & Sons, Ltd.
Perfect timing? Dominant category, dominant design, and the window of opportunity for firm entry
Authors: Suarez Fernando F. , Grodal Stine , Gotsopoulos Aleksios
Published: December 2013

The optimal time to enter emerging industries is a key concern in strategy, yet scholars struggle to create a theoretical foundation that can integrate conflicting empirical findings. We incorporate categorical dynamics to industry life cycle theory to enhance existing entry timing theories. We introduce the concept of a dominant category—the conceptual schema that most stakeholders adhere to when referring to products that address similar needs and compete for the same market space—linking it to the dominant technological design and entry‐timing advantages. In particular, we propose the existence of a window of opportunity for firm entry that starts with the emergence of the dominant category and ends with the emergence of the dominant design. © 2013 The Authors. Strategic Management Journal published by John Wiley & Sons Ltd.
Comments on ‘De Jure and De Facto Validity in the Logic of Time and Modality
Authors: Melia Joseph ,   Philosophy Documentation Center
Published: December 2013

In his paper, Leuenberger (2013) discerns two salient conceptions of logical validity. Strikingly, neither of these conceptions involves modality. He goes on to use these conceptions as a framework to explore certain recent investigations in the logic of modality, where he ingeniously articulates and proves interesting theses about the logic of contingentism. While I think there’s much of interest in Leuenberger’s results, and that his conception of de facto validity gives a unified account of philosophers’ talk of the logic of time and modality, in this note I suggest that perhaps he is too hasty to dismiss the modal conception of validity and that, moreover, his concept of de facto validity may be too inclusive.
The Internationalization Behavior of German High‐Tech Start‐ups: An Empirical Analysis of Key Resources
Authors: Pinkwart Andreas , Proksch Dorian
Published: December 2013

Although there were a lot of new studies about the phenomenon of internationalization in the past several years, the field of newly founded technology‐based firms (NTBFs) internationalization was less considered in literature. We contributed in filling this research gap using a longitudinal study to discover the determinants of internationalization in Germany. Our sample was based on 116 venture capital–financed NTBFs; 44 of them went international. Given the high dependence on exports of the German economy, the internationalization behavior of its NTBFs is of great importance for the future macroeconomic development of the country. In comparison, there are still very few empirical studies on the key determinants and initial drivers for the rapid internationalization of German start‐ups. We showed that technological and financial factors are positively related to going global. The characteristics of the human capital, however, have no significance for going international in our sample. © 2013 Wiley Periodicals, Inc.
Chronic toxicity of parabens and their chlorinated by‐products in Ceriodaphnia dubia
Authors: Terasaki Masanori , Abe Ryoko , Makino Masakazu , Tatarazako Norihisa
Published: December 2013

The chronic toxicity of 12 compounds of parabens and their chlorinated by‐products was investigated using 7‐day Ceriodaphnia dubia test under static renewal condition in order to generate information on how to disinfect by‐products of preservatives that are discharged in aquatic systems. The mortality and inhibition of reproduction tended to increase with increasing hydrophobicity and decreased with the degree of chlorination of parabens. The EC50 values for mortality, offspring number, and first brood production ranged between 0.30–3.1, 0.047–12, and 1.3–6.3 mg L−1, respectively. For the number of neonates, the most sensitive endpoint, the no‐observed‐effect concentration (NOEC) and lowest‐observed‐effect concentration (LOEC) values ranged from 0.63 to 10 mg L−1 and from 1.2 to 19 mg L−1, respectively. Methylparaben (MP), benzylparaben (BnP), and dichlorinated BnP (Cl2BnP) elicited a significant decrease in offspring numbers even at their lowest concentration tested; the NOEC for these compounds was determined to be less than the lowest test concentration (1.3, 0.04, and 0.63 mg L−1 for MP, BnP, and Cl2BnP, respectively). Propylparaben (PP), chlorinated PP, isopropylparaben (iPP), and chlorinated iPP exhibited nonmonotonic concentration‐dependent response; their NOEC and LOEC values could not be determined. The multivariate approach involving principal component analysis and hierarchical cluster analysis revealed four groups that corresponded to the toxicological profiles of parabens. Our results suggested that disinfection of parabens by chlorination could reduce aquatic toxicity of original compounds. The findings obtained in our study together with the data available on paraben concentrations in aquatic systems can be used to perform preliminary risk assessment by comparing the predicted environmental concentration (PEC) with the predicted no‐effect concentration (PNEC) for the marine aquatic environment. The calculated PEC/PNEC ratios ranged from 0.0012 to 0.2, with the highest value observed in MP. This suggested that there are negligible environmental risks for aquatic organisms at current use levels. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 664–673, 2015.
Cystoscopic placement of transurethral stent in a fetus with urethral stenosis
Authors: Ruano R. , Yoshizaki C. T. , Giron A. M. , Srougi M. , Zugaib M.
Published: December 2013

We report the case of a fetus with severe megabladder, displaying the ‘keyhole’ sign on ultrasound imaging, that underwent cystoscopy at 22 weeks' gestation. There was a familial history of mild urethral atresia. Fetal cystoscopy revealed congenital urethral atresia. A guide wire was advanced through the fetal urethra and a transurethral vesicoamniotic stent was placed successfully. The fetus was delivered at 36 weeks' gestation and postnatal cystoscopy confirmed the absence of posterior urethral valves or urethral atresia. The infant was 5 years old with normal renal function at the time of writing. We conclude that fetal cystoscopic placement of a transurethral stent for congenital urethral stenosis is feasible. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd
Effects of a forest pathogen on habitat selection and quality for the endangered golden‐cheeked warbler
Authors: Stewart Laura R. , Morrison Michael L. , Hutchinson Mark R. , Appel David N. , Wilkins R. Neal
Published: December 2013

Oak wilt is a fatal forest disease caused by the fungus Ceratocystis fagacearum. Loss or degradation of habitat caused by oak wilt may negatively affect forest songbirds, including the federally endangered golden‐cheeked warbler (Setophaga chrysoparia), a species that breeds exclusively in the Ashe juniper–oak woodlands (Juniperus ashei–Quercus spp.) of central Texas, USA. During 2010 and 2011, we investigated the influence of oak wilt on golden‐cheeked warbler habitat selection and quality at 25 study sites that each contained forest affected by oak wilt and unaffected forest. We assessed habitat selection in terms of use versus availability at 2 scales: within the patch and within the territory. We also assessed post‐breeding use of affected forest by comparing detection densities in affected and unaffected forest. To assess the influence of oak wilt on habitat quality, we compared the reproductive outcome of territories in unaffected and affected areas. We assessed within‐patch habitat selection for 67 territories and found that golden‐cheeked warblers used affected forest significantly less than its availability. We found use of affected forest to be variable within the 14 territories that contained affected forest in >10% of their area. Post‐breeding use of affected forest was also variable. Pairing success was 27% lower for males whose territories contained >10% affected forest but fledging success was not affected. Our results suggest that the presence of oak wilt negatively influences habitat selection and quality for golden‐cheeked warblers, likely due to reduced canopy cover in susceptible oak species. © 2013 The Wildlife Society.
Urban Land Policies in Ghana: A Case of the Emperor's New Clothes?
Authors: Obeng-Odoom Franklin
Published: December 2013

The paper examines evidence on the reasons for inefficient land management in Ghana. It argues that the perceived custodians of land have consistently acted in their individual interest while successfully using a discourse of ‘communal’ to secure the backing of the colonial and post colonial state. Overall, the state has substantially promoted the interest of private capital. In turn, the ‘public good’ outcomes the current land policies ostensibly seek to achieve have only been modestly achieved. Instead, land policies have had perverse implications for weaker groups such as women and impacted cities negatively.
Lung uptake on I-131 therapy and short-term outcome in patients with lung metastasis from differentiated thyroid cancer
Authors: Okamoto Shozo , Shiga Tohru , Uchiyama Yuko , Manabe Osamu , Kobayashi Kentaro , Yoshinaga Keiichiro , Tamaki Nagara
Published: December 2013

Objective

It is sometimes difficult to assess I-131 lung uptake at the initial I-131 therapy because of strong artifacts from I-131 uptake in the thyroid bed. The aim of this study was to analyze the lung uptake at the second I-131 therapy for lung metastasis in patients who did not have lung uptake at the initial therapy from differentiated thyroid carcinoma (DTC). Then, we also analyzed the relationship between the initial lung uptake and short-term outcome after I-131 therapies.

Methods

This study included 62 DTC patients with lung metastasis. The patients were classified into 2 groups according to the lung uptake at the initial I-131 therapy such as patients with lung uptake (positive uptake group n = 31) and those without lung uptake (negative uptake group n = 31). The lung uptake was analyzed at the second therapy in both groups. The short-term outcome was also analyzed based on the CT findings of lung metastasis size and serum thyroglobulin level between the two groups.

Results

The positive uptake group showed positive lung uptake at the second therapy in 23 patients (74 %), whereas none of negative uptake group showed any lung uptake at the second therapy (P < 0.01). The positive uptake group significantly decreased in the size of lung metastasis from the initial therapy to the second therapy (20.0 ± 11.7 to 16.6 ± 9.6 mm, P < 0.01) with further decrease after the second therapy (P < 0.05). The serum thyroglobulin level was also significantly decreased from the initial therapy to the second therapy (4348 ± 7011 to 2931 ± 4484 ng/ml, P < 0.05). In contrast, the negative uptake group significantly increased in the size of lung metastasis from the initial therapy to the second therapy (17.3 ± 12.2 to 19.9 ± 14.3 mm, P < 0.01) with further increase after the second therapy (P < 0.01).

Conclusion

No patients without lung uptake at the initial I-131 therapy showed lung uptake at the second therapy, or showed treatment effect. Therefore, second I-131 therapy for these patients with initially negative lung uptake should be considered cautiously.
Modeling target bulk heating resulting from ultra-intense short pulse laser irradiation of solid density targets
Authors: Antici P. , Gremillet L. , Grismayer T. , Mora P. , Audebert P. , Borghesi M. , Cecchetti C. A. , Mančic A. , Fuchs J.
Published: December 2013

Isochoric heating of solid-density matter up to a few tens of eV is of interest for investigating astrophysical or inertial fusion scenarios. Such ultra-fast heating can be achieved via the energy deposition of short-pulse laser generated electrons. Here, we report on experimental measurements of this process by means of time- and space-resolved optical interferometry. Our results are found in reasonable agreement with a simple numerical model of fast electron-induced heating.
Dehydration kinetics and conductivity scaling in time near the continuity failure of a water wetting film in granular media
Authors: Moscicki Jozef K. , Sokolowska Dagmara
Published: December 2013

We found that in wet biological and manmade granular materials drying freely to ambient air, dehydration kinetics is quite linear in time in the proximity to the thin, quasi-2D aqueous layer continuity threshold. Electric conductivity of the film scales like a power of time-to-failure. The scaling exponent is to within more or less 15% the same as the corresponding exponent for conductivity scaling with the sample hydration.
Theoretical modeling of the uranium 4f XPS for U(VI) and U(IV) oxides
Authors: Bagus Paul S. , Nelin Connie J. , Ilton Eugene S.
Published: December 2013

A rigorous study is presented of the physical processes related to X-Ray photoelectron spectroscopy, XPS, in the 4f level of U oxides, which, as well as being of physical interest in themselves, are representative of XPS in heavy metal oxides. In particular, we present compelling evidence for a new view of the screening of core-holes that extends prior understandings. Our analysis of the screening focuses on the covalent mixing of high lying U and O orbitals as opposed to the, more common, use of orbitals that are nominally pure U or pure O. It is shown that this covalent mixing is quite different for the initial and final, core-hole, configurations and that this difference is directly related to the XPS satellite intensity. Furthermore, we show that the high-lying U d orbitals as well as the U(5f) orbital may both contribute to the core-hole screening, in contrast with previous work that has only considered screening through the U(5f) shell. The role of modifying the U-O interaction by changing the U-O distance has been investigated and an unexpected correlation between U-O distance and XPS satellite intensity has been discovered. The role of flourite and octahedral crystal structures for U(IV) oxides has been examined and relationships established between XPS features and the covalent interactions in the different structures. The physical views of XPS satellites as arising from shake processes or as arising from ligand to metal charge transfers are contrasted; our analysis provides strong support that shake processes give a more fundamental physical understanding than charge transfer. Our theoretical studies are based on rigorous, strictly ab initio determinations of the electronic structure of embedded cluster models of U oxides with formal U(VI) and U(IV) oxidation states. Our results provide a foundation that makes it possible to establish quantitative relationships between features of the XPS spectra and materials properties.
Fast camera studies at an electron cyclotron resonance table plasma generator
Authors: Rácz R. , Biri S. , Hajdu P. , Pálinkás J.
Published: December 2013

A simple table-size ECR plasma generator operates in the ATOMKI without axial magnetic trap and without any particle extraction tool. Radial plasma confinement is ensured by a NdFeB hexapole. The table-top ECR is a simplified version of the 14 GHz ATOMKI-ECRIS. Plasma diagnostics experiments are planned to be performed at this device before installing the measurement setting at the “big” ECRIS. Recently, the plasma generator has been operated in pulsed RF mode in order to investigate the time evolution of the ECR plasma in two different ways. (1) The visible light radiation emitted by the plasma was investigated by the frames of a fast camera images with 1 ms temporal resolution. Since the visible light photographs are in strong correlation with the two-dimensional spatial distribution of the cold electron components of the plasma it can be important to understand better the transient processes just after the breakdown and just after the glow. (2) The time-resolved ion current on a specially shaped electrode was measured simultaneously in order to compare it with the visible light photographs. The response of the plasma was detected by changing some external setting parameters (gas pressure and microwave power) and was described in this paper.
Status and operation of the Linac4 ion source prototypes
Authors: Lettry J. , Aguglia D. , Andersson P. , Bertolo S. , Butterworth A. , Coutron Y. , Dallocchio A. , Chaudet E. , Gil-Flores J. , Guida R. , Hansen J. , Hatayama A. , Koszar I. , Mahner E. , Mastrostefano C. , Mathot S. , Mattei S. , Midttun Ø. , Moyret P. , Nisbet D. , Nishida K. , O’Neil M. , Ohta M. , Paoluzzi M. , Pasquino C. , Pereira H. , Rochez J. , Sanchez Alvarez J. , Sanchez Arias J. , Scrivens R. , Shibata T. , Steyaert D. , Thaus N. , Yamamoto T.
Published: December 2013

CERN's Linac4 45 kV H− ion sources prototypes are installed at a dedicated ion source test stand and in the Linac4 tunnel. The operation of the pulsed hydrogen injection, RF sustained plasma, and pulsed high voltages are described. The first experimental results of two prototypes relying on 2 MHz RF-plasma heating are presented. The plasma is ignited via capacitive coupling, and sustained by inductive coupling. The light emitted from the plasma is collected by viewports pointing to the plasma chamber wall in the middle of the RF solenoid and to the plasma chamber axis. Preliminary measurements of optical emission spectroscopy and photometry of the plasma have been performed. The design of a cesiated ion source is presented. The volume source has produced a 45 keV H− beam of 16–22 mA which has successfully been used for the commissioning of the Low Energy Beam Transport (LEBT), Radio Frequency Quadrupole (RFQ) accelerator, and chopper of Linac4.
Phenomena of oscillations in atmospheric pressure direct current glow discharges
Authors: Liu Fu-cheng , Yan Wen , Wang De-zhen
Published: December 2013

Self-sustained oscillations in a dc glow discharge with a semiconductor layer at atmospheric pressure were investigated by means of a one-dimensional fluid model. It is found that the dc glow discharge initially becomes unstable in the subnormal glow region and gives rise to oscillations of plasma parameters. A variety of oscillations with one or more frequencies have been observed under different conditions. The discharge oscillates between the glow discharge mode and the Townsend discharge mode in the oscillations with large amplitude while operates in the subnormal glow discharge mode all the while in the oscillations with small amplitude. Fourier Transform spectra of oscillations reveal the transition mechanism between different oscillations. The effects of semiconductor conductivity on the oscillation frequency of the dominant mode, gas voltage, as well as the discharge current have also been analyzed.
Coherent states, 6j symbols and properties of the next to leading order asymptotic expansions
Authors: Kamiński Wojciech , Steinhaus Sebastian
Published: December 2013

We present the first complete derivation of the well-known asymptotic expansion of the SU(2) 6j symbol using a coherent state approach, in particular we succeed in computing the determinant of the Hessian matrix. To do so, we smear the coherent states and perform a partial stationary point analysis with respect to the smearing parameters. This allows us to transform the variables from group elements to dihedral angles of a tetrahedron resulting in an effective action, which coincides with the action of first order Regge calculus associated to a tetrahedron. To perform the remaining stationary point analysis, we compute its Hessian matrix and obtain the correct measure factor. Furthermore, we expand the discussion of the asymptotic formula to next to leading order terms, prove some of their properties and derive a recursion relation for the full 6j symbol.
Graphdiyne as a high-capacity lithium ion battery anode material
Authors: Jang Byungryul , Koo Jahyun , Park Minwoo , Lee Hosik , Nam Jaewook , Kwon Yongkyung , Lee Hoonkyung
Published: December 2013

Using the first-principles calculations, we explored the feasibility of using graphdiyne, a 2D layer of sp and sp2 hybrid carbon networks, as lithium ion battery anodes. We found that the composite of the Li-intercalated multilayer α-graphdiyne was C6Li7.31 and that the calculated voltage was suitable for the anode. The practical specific/volumetric capacities can reach up to 2719 mAh g−1/2032 mAh cm−3, much greater than the values of ∼372 mAh g−1/∼818 mAh cm−3, ∼1117 mAh g−1/∼1589 mAh cm−3, and ∼744 mAh g−1 for graphite, graphynes, and γ-graphdiyne, respectively. Our calculations suggest that multilayer α-graphdiyne can serve as a promising high-capacity lithium ion battery anode.
Water dependence of the dielectric β-relaxation in poly(ɛ-caprolactone)
Authors: Kuttich B. , Lederle C. , Stühn B.
Published: December 2013

Water dependent secondary relaxations are well known in glass formers. In Poly(ɛ-caprolactone) (PCL) both the dielectric and mechanical β-relaxation have a water dependent relaxation strength, whose molecular reasons are still unclear. By systematically varying the water content of the samples, a linear dependency between the dielectric relaxation strength and the number of absorbed water molecules was found, leading to a vanishing relaxation for completely dried samples. Neither the α-relaxation nor the secondary β-relaxation showed water dependent relaxation times and also the glass transition temperature determined by differential scanning microscopy (DSC) is not affected by the water absorption. So far the molecular origins of the dielectric β-relaxation in PCL are not consistent with the observations in other glass formers.