bluuebunny/crossref_metadata_2025 huggingface dataset:
Pretreatment of garden biomass using Fenton’s reagent: influence of Fe2+ and H2O2 concentrations on lignocellulose degradation
Authors: Bhange Vivek P , William SPM Prince , Sharma Abhinav , Gabhane Jagdish , Vaidya Atul N , Wate Satish R
Published: February 2015

Garden biomass (GB) is defined as low density and heterogeneous waste fraction of garden rubbish like grass clippings, pruning, flowers, branches, weeds; roots. GB is generally different from other types of biomass. GB is mostly generated through maintenance of green areas. GB can be processed for bio energy production as it contains considerably good amount of cellulose and hemicellulose. However, pretreatment is necessary to delignify and facilitate disruption of cellulosic moiety. The aim of the present investigation was to pretreat GB using Fenton’s reagent and to study the influence of Fe2+and H2O2concentrations on degradation of lignin and cellulose. The data were statistically analyzed using ANOVA and numerical point prediction tool of MINITAB RELEASE 14 to optimize different process variables such as temperature, concentration of Fe2+and H2O2. The results of the present investigation showed that Fenton’s reagent was effective on GB, however, concentration of Fe2+and H2O2play crucial role in determining the efficiency of pretreatment. An increase in H2O2concentration in Fenton’s reagent significantly increased the rate of cellulose and lignin degradation in contrast to increasing concentration of Fe2+ion which led to a decrease in lignocellulosic degradation.
Cephalometric study to test the reliability of anteroposterior skeletal discrepancy indicators using the twin block appliance
Authors: Trivedi Rahul , Bhattacharya Amit , Mehta Falguni , Patel Dolly , Parekh Harshik , Gandhi Vaibhav
Published: February 2015

Background

The objectives of this study were to check the reliability of the five angular and two linear parameters for sagittal maxillo-mandibular discrepancy and to compare and correlate angular parameters with the ANB angle, and the linear parameter with Wits analysis.

Methods

The pre-treatment and post-functional lateral cephalograms of 25 subjects (17 males, 8 females) with class II division 1 malocclusion treated with twin block functional appliance were selected. Five angular (ANB, β angle, APDI, YEN angle, W angle) and two linear (Wits analysis, App-Bpp) parameters were traced on both sets of cephalograms. Paired Student’s t-test, one-way ANOVA, post hoc test, and Karl Pearson correlation statistical analysis were performed.

Results

All the parameters considered in our study showed highly significant difference in pre-treatment and post-functional values, suggesting their reliability (p < 0.0001). When ANB angle was compared with the other angular parameters, a highly significant change in the mean value of the difference in pre-treatment (T1) and post-functional (T2) values was noted (p < 0.001). No significant change was seen when comparing the mean value of the difference in T1 and T2 between linear parameters (p = 0.949).

Conclusions

All the parameters used in the study can be reliably used to assess anteroposterior skeletal discrepancy. Whenever limitations of the ANB angle and Wits analysis are foreseen, the W angle and App-Bpp, respectively, can be reliably used. The YEN angle may reliably predict the post-functional change with the use of twin block appliance.
Effects of yam dioscorin interventions on improvements of the metabolic syndrome in high-fat diet-induced obese rats
Authors: Shih Shen-Liang , Lin Yin-Shiou , Lin Shyr-Yi , Hou Wen-Chi
Published: February 2015

Background

The metabolic syndrome (MS) is termed a cluster of multiple metabolic risk criteria which is positively correlated with cardiovascular disease and type 2 diabetes mellitus (DM). Yam dioscorins have been reported to exhibit biological activities, however, little is known their preventive effects on the MS. Therefore, a high-fat (HF) diet was used to induce Wistar rat obesity and then yam dioscorin (50 mg/kg, dio50) was intervened daily concurrent HF diet (HF diet + dio50) for five weeks to check the changes of weights of body and tissues, blood pressures, and impaired glucose tolerances. The in vitro peptic hydrolysates of dioscorin with molecular mass between 3 kDa and 10 kDa and less than 3 kDa were used to determine dipeptidyl peptidase IV (DPP IV) inhibitory activities which DPP IV inhibitor has been reported to prevent and treat type 2 DM.

Results

There were no significant difference in body weights, feed intakes, feed conversion, and weights of adipose tissues of obese rats in groups of HF and (HF diet + dio50). However, the systolic blood pressures in obese rats of 2-, 3- and 4-week dioscorin interventions were showed significantly lower (P < 0.05) compared to the HF group. The dioscorin intervention (HF+ dio50) was showed significantly different (P < 0.05) and improved the impaired glucose tolerances compared to HF group in obese rats by the oral glucose tolerance tests. It was also found that the fraction with different molecular mass of dioscorin peptic hydrolysates (5 mg/ml) showed inhibitory activities against DPP IV using sitagliptin phosphate as positive controls.

Conclusions

Yam dioscorins exhibit improved MS activities in obese rats which the related mechanisms may need further investigations.
TNF-α-Induced NF-κB Activation Stimulates Skeletal Muscle Glycolytic Metabolism Through Activation of HIF-1α
Authors: Remels A. H. V. , Gosker H. R. , Verhees K. J. P. , Langen R. C. J. , Schols A. M. W. J.
Published: February 2015

A shift in quadriceps muscle metabolic profile toward decreased oxidative metabolism and increased glycolysis is a consistent finding in chronic obstructive pulmonary disease (COPD). Chronic inflammation has been proposed as a trigger of this pathological metabolic adaptation. Indeed, the proinflammatory cytokine TNF-α impairs muscle oxidative metabolism through activation of the nuclear factor-κB (NF-κB) pathway. Putative effects on muscle glycolysis, however, are unclear. We hypothesized that TNF-α-induced NF-κB signaling stimulates muscle glycolytic metabolism through activation of the glycolytic regulator hypoxia-inducible factor-1α (HIF-1α). Wild-type C2C12 and C2C12-IκBα-SR (blocked NF-κB signaling) myotubes were stimulated with TNF-α, and its effects on glycolytic metabolism and involvement of the HIF pathway herein were investigated. As proof of principle, expression of HIF signaling constituents was investigated in quadriceps muscle biopsies of a previously well-characterized cohort of clinically stable patients with severe COPD and healthy matched controls. TNF-α increased myotube glucose uptake and lactate production and enhanced the activity and expression levels of multiple effectors of muscle glycolytic metabolism in a NF-κB-dependent manner. In addition, TNF-α activated HIF signaling, which required classical NF-κB activation. Moreover, the knockdown of HIF-1α largely attenuated TNF-α-induced increases in glycolytic metabolism. Accordingly, the mRNA levels of HIF-1α and the HIF-1α target gene, vascular endothelial growth factor (VEGF), were increased in muscle biopsies of COPD patients compared with controls, which was most pronounced in the patients with high levels of muscle TNF-α. In conclusion, these data show that TNF-α-induced classical NF-κB activation enhances muscle glycolytic metabolism in a HIF-1α-dependent manner.
Dapagliflozin Lowers Plasma Glucose Concentration and Improves β-Cell Function
Authors: Merovci Aurora , Mari Andrea , Solis Carolina , Xiong Juan , Daniele Giuseppe , Chavez-Velazquez Alberto , Tripathy Devjit , Urban McCarthy Scheherezada , Abdul-Ghani Muhammad , DeFronzo Ralph A.
Published: February 2015

Background:

β-Cell dysfunction is a core defect in T2DM, and chronic, sustained hyperglycemia has been implicated in progressive β-cell failure, ie, glucotoxicity. The aim of the present study was to examine the effect of lowering the plasma glucose concentration with dapagliflozin, a glucosuric agent, on β-cell function in T2DM individuals.

Research Design and Methods:

Twenty-four subjects with T2DM received dapagliflozin (n = 16) or placebo (n = 8) for 2 weeks, and a 75-g oral glucose tolerance test (OGTT) and insulin clamp were performed before and after treatment. Plasma glucose, insulin, and C-peptide concentrations were measured during the OGTT.

Results:

Dapagliflozin significantly lowered both the fasting and 2-hour plasma glucose concentrations and the incremental area under the plasma glucose concentration curve (ΔG0–120) during OGTT by −33 ± 5 mg/dL, −73 ± 9 mg/dL, and −60 ± 12 mg/dL · min, respectively, compared to −13 ± 9, −33 ± 13, and −18 ± 9 reductions in placebo-treated subjects (both P < .01). The incremental area under the plasma C-peptide concentration curve tended to increase in dapagliflozin-treated subjects, whereas it did not change in placebo-treated subjects. Thus, ΔC-Pep0–120/ΔG0–120 increased significantly in dapagliflozin-treated subjects, whereas it did not change in placebo-treated subjects (0.019 ± 0.005 vs 0.002 ± 0.006; P < .01). Dapagliflozin significantly improved whole-body insulin sensitivity (insulin clamp). Thus, β-cell function, measured as ΔC-Pep0–120/ ΔG0–120 ÷ insulin resistance, increased by 2-fold (P < .01) in dapagliflozin-treated vs placebo-treated subjects.

Conclusion:

Lowering the plasma glucose concentration with dapagliflozin markedly improves β-cell function, providing strong support in man for the glucotoxic effect of hyperglycemia on β-cell function.
Research Resource: The Dynamic Transcriptional Profile of Sertoli Cells During the Progression of Spermatogenesis
Authors: Zimmermann Céline , Stévant Isabelle , Borel Christelle , Conne Béatrice , Pitetti Jean-Luc , Calvel Pierre , Kaessmann Henrik , Jégou Bernard , Chalmel Frédéric , Nef Serge
Published: February 2015

Sertoli cells (SCs), the only somatic cells within seminiferous tubules, associate intimately with developing germ cells. They not only provide physical and nutritional support but also secrete factors essential to the complex developmental processes of germ cell proliferation and differentiation. The SC transcriptome must therefore adapt rapidly during the different stages of spermatogenesis. We report comprehensive genome-wide expression profiles of pure populations of SCs isolated at 5 distinct stages of the first wave of mouse spermatogenesis, using RNA sequencing technology. We were able to reconstruct about 13 901 high-confidence, nonredundant coding and noncoding transcripts, characterized by complex alternative splicing patterns with more than 45% comprising novel isoforms of known genes. Interestingly, roughly one-fifth (2939) of these genes exhibited a dynamic expression profile reflecting the evolving role of SCs during the progression of spermatogenesis, with stage-specific expression of genes involved in biological processes such as cell cycle regulation, metabolism and energy production, retinoic acid synthesis, and blood-testis barrier biogenesis. Finally, regulatory network analysis identified the transcription factors endothelial PAS domain-containing protein 1 (EPAS1/Hif2α), aryl hydrocarbon receptor nuclear translocator (ARNT/Hif1β), and signal transducer and activator of transcription 1 (STAT1) as potential master regulators driving the SC transcriptional program. Our results highlight the plastic transcriptional landscape of SCs during the progression of spermatogenesis and provide valuable resources to better understand SC function and spermatogenesis and its related disorders, such as male infertility.
Synthesis and Properties of (Terthiophene)4–Poly(amidoamine)–C60 Pentad
Authors: Tajima Tomoyuki , Nishihama Takuya , Miyake Shogo , Takahashi Nobuhiro , Takaguchi Yutaka
Published: February 2015

(Terthiophene)4–poly(amidoamine)–C60 pentad 8a and (terthiophene)2–poly(amidoamine)–C60 triad 8b have been synthesized with the aim of developing novel precursors for photoinduced polymerization. The electrochemical oxidation of pentad 8a by repetitive cyclic voltammogram scans gave a polymeric 8a film on a FTO electrode, which showed electrochemical activity and photoelectric response. When a monomer film of 8 on FTO was irradiated with visible light, the photoinduced polymerization of the terthiophene moiety was observed. The photoanodic features of an electropolymerized film of 8a on a FTO (poly-8aelectro/FTO) and 8a/FTO were investigated regarding photocurrent response to light irradiation. The photocurrent of a photopolymerized 8a film on a FTO (poly-8aphoto/FTO) electrode formed by photoreaction of 8a/FTO, is approximately 6 times greater than that of the 8a/FTO electrode.
Thermal shock and wear behavior of zirconate thermal barrier coatings
Authors: Purushothama K. , Shivarudraiah Dr
Published: February 2015

High temperature thermal shock causes the breakdown of Thermal Barrier Coating (TBC) systems. This paper focusing attention on the Zirconate TBC coating to study the thermo mechanical behavior such as wear and thermal shock test has been conducted inter metallic bond coat and Zirconate TBC to know the wear and thermal characteristics, and wear behavior has been studied on intermetallic bond coat using dry abrasion test and thermal characteristics studied on Zirconate TBC systems using thermal shock resistance test and finally the coatings characteristics before and after thermal cycling were evaluated.
A finite element study on effect of frictional heating in the taylor rod impact problem
Authors: Gautam Sachin , Saxena Ravindra
Published: February 2015

In an impact phenomenon the material is subjected to very short duration high force levels resulting large plastic deformations and rise in temperature at high strain rates. A circular rod impacting against a rigid surface called as Taylor rod impact test is widely used for determining the mechanical behaviour of materials subjected to high strain rates with associated increase in temperature. A three-dimensional large deformation, thermo-elasto-plastic, dynamic, contact, finite element formulation is developed to study the effect of temperature rise due to plastic deformation and surface friction on the deformation and stress fields. It is found that the predicted equivalent plastic strain values are influenced by temperature generated due to plastic deformation and surface friction. The values of the coefficient of friction have a profound effect on the location of fracture initiation on the impacting face in a circular rod.
Effect of palmyra palm fiber filler on properties of natural rubber vulcanizate
Authors: Nwabanne J. , Igbokwe P. , Ezeonyebuchi E.
Published: February 2015

The effect of partial replacement of carbon black by Palmyra palm fiber on the cure characteristics, physico-mechanical and swelling properties of natural rubber vulcanizates was studied. The Palmyra palm fibers were extracted, treated and characterized so as to determine pH, moisture content, and ash content, loss on ignition, conductivity, cellulose, lignin, Hemicellulose, cellulose/lignin ratio and Acid soluble lignin. The functional groups in the Palmyra palm fiber was also determined using FTIR. The Palmyra palm powder with an average particle size of 75 μm was used in this study. The natural rubber/carbon black/Palmyra palm fiber (NR/CB/PPF) composites having eight different loadings, 0/70, 10/60, 20/50, 30/40, 40/30, 50/20, 60/10, 70/0, were prepared using a laboratory size two roll mill. The maximum Torque of NR/CB/PPF composites increased with increasing commercial filler loading ratio. The scorch time and cure time of NR/CB/PPF composites decreased as the ratio of CB loading increased. The tensile strength, modulus of elongation, tear strength and abrasion resistance of all the composites increased as the commercial filler loading ratio increased. This is due to the presence of the commercial filler which gave a better filler interaction. Also this behavior can be attributed to the particle size and surface area of the fillers used as the fillers with small particle size usually have a larger surface area which supports better filler-rubber interaction. The hardness increased as the palmyra palm fiber loading increased. The elongation at break decreases as carbon black filler loading increases except for the composite with CB/PPF ratio of 10/60. The effect of filler loading on the swelling behavior of NR/CB/PPF composites was also investigated in aromatic and aliphatic compounds. Result showed that the composites with more carbon black has less absorption than those with more palmyra palm fiber showing that the compounds with more carbon black has better interaction than those with palmyra palm fiber.
Analysis of flux cored arc welding process parameters by hybrid taguchi approach
Authors: Sreeraj P. , Kannan T. , Subhasis Maji
Published: February 2015

This paper presents calculation of the welding process parameters for obtaining optimal weld bead geometry in Flux Cored arc welding (FCAW) process. Bead on plate welding was carried as per L16 orthogonal array. In this paper weld bead geometry such as penetration, bead width, reinforcement and percentage of dilution of IS 2062 structural steel plates investigated. Two hybrid techniques firstly Taguchi method coupled with Grey relational analysis and secondly Taguchi method in combination with desirability function (DF) approach has been applied in this paper. Comparison made between two hybrid optimization techniques are made to analyze to choose the best method. Optimal results have been confirmed by confirmatory experiment which showed satisfactory results.
Performance analyses of mixed-flow pumping systems for S-to-N water diversion project in China
Authors: Zhang Rentian , Li Longhua , Zhu Honggeng , Yao Linbi , Shi Wei
Published: February 2015

There are three pumping stations in the first stage of Eastern Route S-to-N Water Diversion Project in China, where the mixed-flow pumps with guide vanes are installed, consisting of Baoying, Hongze and the No. 2 Suining pumping stations. By using flow rate coefficient and head coefficient as expression, firstly the hydraulic performances of the hydro models used are analyzed. Secondly the structural features and system performances are compared. And finally the measurement results in site are comprehensively evaluated. The results show that the pump models both introduced abroad and developed at home and the pumping system types adopted in the three pumping stations have been confirmed satisfying the requirements of operational conditions and high efficiency, stable and safety operation in all working conditions can be ensured.
An Exploratory Study on a Chest‐Worn Computer for Evaluation of Diet, Physical Activity and Lifestyle
Authors: Sun Mingui , Burke Lora E. , Baranowski Thomas , Fernstrom John D. , Zhang Hong , Chen Hsin-Chen , Bai Yicheng , Li Yuecheng , Li Chengliu , Yue Yaofeng , Li Zhen , Nie Jie , Sclabassi Robert J. , Mao Zhi-Hong , Jia Wenyan
Published: February 2015

Recently, wearable computers have become new members in the family of mobile electronic devices, adding new functions to those provided by smartphones and tablets. As "always‐on" miniature computers in the personal space, they will play increasing roles in the field of healthcare. In this work, we present our development of eButton, a wearable computer designed as a personalized, attractive, and convenient chest pin in a circular shape. It contains a powerful microprocessor, numerous electronic sensors, and wireless communication links. We describe its design concepts, electronic hardware, data processing algorithms, and its applications to the evaluation of diet, physical activity and lifestyle in the study of obesity and other chronic diseases.
Service Systems with Slowdowns: Potential Failures and Proposed Solutions
Authors: Dong Jing , Feldman Pnina , Yom-Tov Galit B.
Published: February 2015

Many service systems exhibit service slowdowns when the system is congested. Our goal in this paper is to investigate this phenomenon and its effect on system performance. We modify the Erlang-A model to account for service slowdowns and carry out the performance analysis in the quality- and efficiencydriven (QED) regime. We find that when the load sensitivity is low, the system can achieve QED performance, but the square-root staffing parameter requires an adjustment to achieve the same performance as an ordinary Erlang-A queue. When the load sensitivity is high, the system alternates randomly between a QED and an efficiency-driven (ED) regime performance levels, a phenomenon that we refer to as bistability. We analyze how the system scale and model parameters affect the bistability phenomenon and propose an admission control policy to avoid ED performance.
Citizenship in a financialised society: financial inclusion and the state before and after the crash
Authors: Berry Craig
Published: February 2015

Financialisation, understood as the increased role of finance in individuals’ daily lives as well as the economy in general, has profound implications for the relationship between individuals and the state. This article therefore interrogates recent developments in welfare provision in the UK, in particular the ‘financial inclusion’ agenda, in order to assess how financialisation is affecting the nature and practice of citizenship. By associating institutional change with the UK’s prevailing model of economic growth, it offers an original account of both the persistence of the financial inclusion agenda despite challenges posed by the financial crisis, and the ‘responsibilisation’ of citizenship.
Critical social work as ethical social work: using critical reflection to research students’ resistance to neoliberalism
Authors: Morley Christine
Published: February 2015

This article explores possibilities and responsibilities for social work to further a social justice and human rights agenda in a neoliberal context through the prism of ethical practice. We draw on examples from a progressive social work programme that places critical theories at the centre of curricula and links them explicitly with the distinct value and ethical base of the social work profession. We demonstrate how critical reflection facilitates students’ commitment to the values and principles of critical social work, and the ways in which this fosters resistance to the colonisation of social work by neoliberalism. We conclude with some examples taken from our research that illustrate the emancipatory possibilities of critical reflection to enhance ethical practice in critical social work.
Retreating in/from art institutions
Authors: Anderson Heather
Published: February 2015

All too frequently individuals working in art institutions are faced with the frustrating contradiction that the quality engagement with art and ideas that are the institution's raison d'être, and the concentrated research and writing that are a vital part of, for instance, curatorial work are compromised by workload and have to be eked out in less-than-efficient spurts, fit in after regular working hours, or postponed altogether. This text explores some of the reasons conditions of overwork exist in art institutions and how slow time for working with art, artists and ideas might be reprioritized by looking at recent examples of art institutions that have employed strategies of retreat and withdrawal. The text also proposes that given the prevalence and normalization of conditions of overwork as well as an increasing reliance on unpaid labour in the field, art institutions have an ethical responsibility to refuse such exploitative conditions and commit to doing less when human and financial resources are insufficient.
INTRODUCTION: "Between the Exception and the Rule"
Authors: Szema Imre , Blacker Sarah
Published: February 2015

Introduction to issue of PUBLIC 50 on "The Retreat."
The Daily Sleeper (excerpts); 10/08/12
Authors: Bristol Joanne
Published: February 2015

Through a desire to articulate modes of multispecies agency, data were gathered in response to material, spatial and temporal qualities of Sleeping Buffalo (Tunnel) mountain - or iniskim - during The Retreat residency at the Banff Centre. In an attempt to 'retreat' from forms exclusive to art, data are presented using the ubiquitous structures of 'newspaper' and 'postcard'.
Reviews
Authors: Loydell Rupert , Dale Pete
Published: February 2015

Future Days. Krautrock and the Building of Modern Germany, David Stubbs (2014) Faber, London, 495 pp., ISBN: 9780571283323, p/bk, £20.00

Fight Back: Punk, Politics and Resistance, The Subcultures Network (2015) Manchester: Manchester University Press, 319 pp., ISBN: 9780719090295, h/bk, £75
Development of Inexpensive SiGe–FeSi2 Thermoelectric Nanocomposites
Authors: Abudakka Mohamed , Nozariasbmarz Amin , Tayebi Lobat , Krasisnki Jerzy S. , Vashaee Daryoosh
Published: February 2015

This investigation presents cost-effective fabrication of n-type silicon germanium–iron disilicide nanocomposites using low-cost low-purity germanium–germanium oxide powder. Moreover, the probability of the reduction of oxide powders during the synthesis process was studied. X-ray diffraction (XRD) analysis indicated reduction of germanium oxide impurity in the synthesized material. Scanning electron microscopy (SEM) along with the energy-dispersive spectrometer (EDS) showed a structure of dispersed iron disilicide particles embedded in silicon germanium matrix. The nanocomposite structure showed a moderate figure-of-merit, ZT, equal to 0.8. The ZT enhancement was related to both the nanocomposite structure and the reduction of germanium oxide.
Extending Constructivist Perspectives on Opportunity Production Through An Incorporation of Effectual Logics
Authors: Metzger Matthew L. , King Jesse S.
Published: February 2015

Current constructivist theorizing relies heavily on causal logics and, therefore, posits that entrepreneurs either pursue or abandon perceived opportunities shortly after their inception. However, findings from effectuation research illuminate less-direct processes involved in the establishment of entrepreneurial ventures. We describe how effectual and causal logics might be integrated by proposing a supplemented model of entrepreneurial opportunity production that features an alternative effectual pathway. In describing this model, we develop six propositions to explain the unique pattern of cognitions and behaviors found among entrepreneurs employing effectual logics. Our propositions suggest that these entrepreneurs are unlikely to rely on peer feedback to determine the viability of early stage opportunities. Instead, they delay the objectification and evaluation of opportunities because they recognize that predictions made in uncertain environments are unlikely to be correct. The employment of these alternate logics results in different pathways to commercialization and different consequences associated with failures.
Negative Selection of Artificial Immune Applied to Voltage Inadequacy Detection in Distribution Networks
Authors: Delboni Luiz Fernando , Zambroni da Silva Antonio Carlos , Oliveira Denisson Queiroz
Published: February 2015

The problem of voltage control and reactive power management plays a crucial role on power system’s operations. Particularly, detecting the most effective control actions to reduce the system loss and enhance the voltage profile is of major interest. This paper deals with system voltage inadequacy detection. To address this problem, artificial immune system is employed considering its negative selection mechanism. Its purpose is to monitor system operation data entry and check if the voltage level is within its operating values. In this sense, the user may define the range of control, so the proposed methodology may be useful for normal and emergency operating conditions. Corrective actions are undertaken if necessary. The IEEE 34 nodes distribution system is used to test the proposed methodology.
Estimation of heat loss from a cylindrical cavity receiver based on simultaneous energy and exergy analyses
Authors: Madadi Vahid , Tavakoli Touraj , Rahimi Amir
Published: February 2015

This study undertakes the experimental and theoretical investigation of heat
losses from a cylindrical cavity receiver employed in a solar parabolic dish
collector. Simultaneous energy and exergy equations are
used for a thermal performance analysis of the system. The effects of wind speed and its direction
on convection loss has also been investigated.
The effects of operational parameters, such as heat transfer fluid mass flow rate and wind speed, and
structural parameters, such as receiver geometry and inclination, are
investigated. The portion of radiative heat loss is less than 10%.
An empirical and simplified correlation for estimating the dimensionless
convective heat transfer coefficient in terms of the

Re

$\mathrm {Re}$

number and the average
receiver wall temperature is proposed. This correlation is applicable for
a wind speed range of

0
.
1

$0.1$

to 10 m/s. Moreover, the proposed correlation for

Nu

$\mathrm {Nu}$

number
is validated using experimental data obtained through the experiments
carried out with a conical receiver with two aperture diameters.
The coefficient of determination R
2 and the normalized root mean square error (NRMSE) parameters were calculated, and the results show that there is a good agreement between predicted results
and experimental data. R
2 is greater than

0
.
95

$0.95$

and the NRMSE parameters
is less than

0
.
06

$0.06$

in this analysis.
Study of triplet periodicity differences inside and between genomes
Authors: Suvorova Yulia M. , Korotkov Eugene V.
Published: February 2015

Triplet periodicity (TP) is a distinctive feature of the protein coding sequences of both prokaryotic and eukaryotic genomes. In this work, we explored the TP difference inside and between 45 prokaryotic genomes. We constructed two hypotheses of TP distribution on a set of coding sequences and generated artificial datasets that correspond to the hypotheses. We found that TP is more similar inside a genome than between genomes and that TP distribution inside a real genome dataset corresponds to the hypothesis which implies that a common TP pattern exists for the majority of sequences inside a genome. Additionally, we performed gene classification based on TP matrixes. This classification showed that TP allows identification of the genome to which a given gene belongs with more than 85% accuracy.
Dynamical Diffraction Equations for Imperfect Crystals
Authors: Kuriyama Masao
Published: February 2015

The ray theory of Kato and Kambe for imperfect crystals is derived in a formal way from a general dynamical theory of diffraction. This development together with the results from a previous paper concerning Takagi's equation (the wave theory) helps to clarify the meaning and limits of various phenomenological theories that have been extended to an imperfect crystal from the dynamical diffraction theory for a perfect crystal.
X-Ray Interferometry of Volume Changes in C+Implanted Silicon
Authors: Schwuttke G. H. , Brack K.
Published: February 2015

High energy C+ implantation is used to construct a two crystal monolithic X-ray interferometer. The X-ray interferometer technique is applied to in-situ studies of radiation damage annealing in the interferometer. Volume changes in the crystal due to the transformation of single crystal silicon to amorphous silicon and due to the formation of silicon carbide are measured.
Quenching Rates for Metastable Oxygen Atoms(5S0)
Authors: Roth E.-P. , Perner D. , Dreyer J. W.
Published: February 2015

Metastable O (3s 5S0) atoms were produced by rare gas sensitized decomposition of various oxygen containing compounds. The quenching rate constants of H2 , N2, O2 , NO, N2O, N2O4/NO2, CO, CO2, SO2 , SO3 , H2O and the noble gases for the 0 (5S) have been measured by absorption spectroscopy. The noble gases, except xenon, deactivate the metastable oxygen atom with low collision efficiency. Xenon and molecular gases, except hydrogen, deactivate this species efficiently, the cross section being of the order of gas kinetic cross sections.
Notizen: Determination of Electron Density in Plasmas from the Hydrogen Spectral Line Hα Broadened by Combined Stark and Zeeman Effect
Authors: Nguyen-Hoe  , Drawin H. W.
Published: February 2015

A method is described which permits a rapid determination of the electron density in plasmas from the spectral line Hα broadened by combined Stark and Zeeman effect.
Zur Theorie der NMR-Spektren von symmetrischen Spinsystemen mit beliebigem Spin I / On the Theory of NMR-Spectra of Symmetrical Spin System with Arbitrary Spin I
Authors: Kleindienst Heinz
Published: February 2015

In this paper a group theoretical method for the determination of the optimal factorization of the Hamiltonian matrix is presented.
Hyperfeinstruktur von AlJ / Hyperfine Structure of AlI
Authors: Törring T. , Tiemann E. , Hoeft J.
Published: February 2015

The quadrupole hyperfine structure of 27A1127I was measured on the rotational transition J = 1 → 2 and 14 GHz. Observations in various vibrational states resulted in the following quadrupole coupling constants:

eq0Q (27Al) =-25.50(10) MHz,

eqvQ{127I) =-307.407-4.315 (ν+1/2) ±0.100 MHz.

The magnetic spin-rotation-interaction of the iodine nucleous was included in the calculation. We obtained as coupling constant:

cI (127I) = + 13.3(10) kHz.
Phase Compensation in Multi-Pulse N.M.R. Experiments
Authors: Mansfield P. , Haeberlen U.
Published: February 2015

A general scheme is described for self correcting the various coherent phase errors that arise in multi-pulse sequences used for artificial narrowing of the absorption line in solids. The scheme is found to work well experimentally and greatly facilitates the phase alignment procedure by reducing the sensitivity of the multi-pulse response to phase control settings and drifts. First order dipolar terms reintroduced into the average Hainiltonian by the phase errors are also discussed.
MPD-Ringkanalströmungen in gekreuzten Fremdfeldern für willkürliche Hall-Parameter / MPD Annular Duct Flow in a Crossed-Field Device for Arbitrary Values of the Hall Parameter
Authors: Robert K.
Published: February 2015

The steady, supersonic, barotropic, and inviscid flow of a rarefied gas plasma through an axisymmetric crossed-field device (imposed axial electric field and radial magnetic induction) is being analyzed, for arbitrary values of the Hall parameter. A previously developed perturbation method is used to obtain closed form solutions for the electric current density, flow velocity, and mass density within the annular duct. Conditions for optimal values of the Hall parameter are given.
Molekūlstrukturen von Phoshorverbindungen / Molecular Structure of Phosphorus Compounds. 1. Trimethylphosphate
Authors: Trimethylphosphat I. , Oberhammer H.
Published: February 2015

The molecular structure of Trimethylphosphate O = P(OCH3)3 has been determined in the vapour phase by electron diffraction. The best fit of the experimental scattering intensity was obtained by assuming two rotational isomers with C3-symmetry occuring in a ratio of approximately 3:1. The geometric parameters and mean square amplitudes are given in the article.
Brillouin Scattering in Liquids at 4416 Å and 4765 Å
Authors: Gustafsson Silas E. , Knape H. E. Gunilla , Torell Lena M.
Published: February 2015

An argon ion laser operating at 4765 Å and a helium-cadmium laser operating at 4416 Å have been used as radiation sources to study Brillouin scattering in seven organic liquids. The Brillouin spectra were investigated at 90° with a pressure scanned Fabry-Perot spectrometer. The measured frequency shifts between the Stokes and anti-Stokes lines were used to determine the hypersonic velocities of thermal waves at frequencies between 4.8 and 7.2 GHz. No dispersion of the hypersound could be detected.
Triplet State Donor-Acceptor Intermediates in Sulphur Dioxide Solutions
Authors: Donbavand M. , Möckel H.
Published: February 2015

Paramagnetism in solutions of tertiary aliphatic amines and related compounds in liquid sulphur dioxide is reported. Evidence is presented that the paramagnetic species in triethylamine solutions is a triplet electronic state lying some 0.32 eV (5.1×10-20 joules) above a diamagnetic groundstate of an n-kπ donor-acceptor complex. The time-dependence of paramagnetism, optical absorption, and electrical conductivity of such solutions has also been investigated and an attempt is made to correlate these phenomena in terms of charge-transfer mechanisms. Finally a few properties of solutions of some similar compounds in liquid SO2 are noted and discussed briefly.
Über die Wendel-Instabilität konvektionsstabilisierten Hochstrom-Hochdruck-Lichtbogens / The Helix Instability of a Convection Stabilized High-Current, High-Pressure Arc
Authors: Ragaller K. , Kogelschatz U. , Schneider W. R.
Published: February 2015

The helix instability of a convection stabilized high current arc burning in a high pressure nitrogen gas flow is investigated theoretically and experimentally. Equations for the electric and magnetic fields and the current density are solved in helix coordinates for small displacements. The resulting electromagnetic force on a helix segment is calculated and compared to the gasdynamic stabilizing forces. A formula is derived for the growth rate as a function of helix pitch and the physical parameters current density and gas density. The comparison with experimental data yields good qualitative agreement for the onset and the growth rate of the helix instability.
Analysis of Formation of the Suppression Effect of Nuclear Reaction Inelastic Channels in the Presence of Hyperfine Splitting
Authors: Kagan Yu. , Afanas'ev A. M.
Published: February 2015

The analysis, carried out in the work, of the emergence of the effect of suppression of the nuclear reaction (ES) during resonance Bragg scattering of Mössbauer gamma-quanto from nuclei under conditions of a hyperfine splitting allows to clearly reveal the fundamental features characteristic of this phenomenon. An is shown in sections 3 and 4, in a general case of realization of ES neither electric nor magnetic vectors of the wave field in the crystal turn to zero at the points of equilibrium positions of the nuclei. For the reaction to be suppressed, it is necessary that the total amplitude of the excited nucleus formation be zero. In this case, a rather peculiar picture of the electromagnetic field within the crystal sets in which depends on the character of the hyperfine splitting and on the multiplicity of the transition.

In this work, conditions have been found of the coexistence of ES for both polarizations, and with these conditions being fulfilled, the strongly resonantly absorbing crystal becomes transparent for the whole of radiation. Special attention has been paid to the proof that lattice vibrations do not restore the nuclear absorption of gamma-quanta. It is interesting that all this takes place during resonant interaction with a separate nucleus when the cross-section of the inelastic process may be large as compared with the elastic scattering cross-section. Although all these features (and a number of others discussed in detail in the text) essentially distinguish ES from the Borrmann effect for X-rays, there is a circumstance which makes them related. In both cases it is necessary to produce a coherent superposition of waves within the crystal owning to the Bragg diffraction of the incident quanta, and in the both cases the crystal becomes more transparent for the radiation that comes through.
Anwendung der Weitwinkelinterferenzen zur Untersuchung von akusto-elektrischen Gitterschwingungen in Kadmiumsulfid / Application of the Pseudo-Kossel-Line-Technique for the Investigation of Acoustoelectric Lattice Jibrations in Cadmium Sulfide
Authors: Kies Jörg , Peibst Herbert
Published: February 2015

Changes in absolute and relative intensities of Pseudo-Kossel lines from crystals containing lattice vibrations were observed. Since the relation between vibration amplitude and intensity modification is known theoretically, vector amplitudes and gain factors of the acoustoelectric amplification can be determined. Advantages of this method are discussed.
NMR investigations and nuclear magnetic moment of 33S
Authors: Lutz O. , Nolle A. , Schwenk A.
Published: February 2015

The ratio of the Larmor frequencies of 33S and 85Rb has been measured and a magnetic moment for 33S of μ(33S in SO4
2- in D2O) =0.643 1028(14)/μN has been calculated.

33S chemical shifts have been determined and the SO4
2- ion in aqueous alkali sulfate solutions is proposed as 33S NMR reference compound.
Mittlere Schwingungsaniplituden einiger tetragonal-pyramidaler XF5
–-Ione / Mean Amplitudes of Vibration of Some Square Pyramidal XF5
– Ions
Authors: Baran Enrique J.
Published: February 2015

Mean amplitudes of vibration for the ions SF5
-, SeF5
- and TeF5
- have been calculated from spectroscopic data using an approximation method. The results are briefly discussed, especially in relation with those of isoelectronic species.
Das Rotationsspektrum des JF/ Rotational Spectrum of IF
Authors: Tiemann E. , Hoeft J. , Törring T.
Published: February 2015

IF was produced by microwave discharge of l2 and C6F10(CFa)2. The rotational transitions J=0→1 and 1→2 in the vibrational states ν = 0, 1, 2 were observed. The analysis of the hyperfine structure yields the following hfs constants:

127I: e qv Q = (-3440.89+5.47 (ν+½) ±0.20) MHz,

cI = ( + 90 ±10) kHz.
Calculation of Population Densities of Helium Atoms in Non-L.T.E. Plasmas
Authors: Drawin H. W. , Emard F. , Katsonis K.
Published: February 2015

Particle densities of helium atoms in the ground and excited states have been calculated for non-L.T.E. plasmas on the basis of a collisional-radiative model in which singlet and triplet states have separately been taken into account. Distinction is made between two physical situations: 1- a homogeneous stationary state, 2- a transient and/or inhomogeneous plasma state. In both cases, the particle densities have been calculated for an optically thin, a slightly optically thick and strongly absorbing plasmas. Only the results for the homogeneous stationary state are presented in this paper. Those for the transient and/or inhomogeneous states have been summarized in numerical tables which will be sent on request. (Title: "Tables of reduced population coefficients for the levels of atomic helium", Report EUR-CEA-FC-697.) The tables are sufficiently complete to permit a wide application in the field of spectroscopic diagnostics of different types of non-L.T.E. plasmas. - Comparison of our results with the values measured by Boersch et al. 10 shows good agreement with our calculations when one assumes that the observed plasma is strongly inhomogeneous and dominated by diffusion.
Solute and Temperature Induced Pitch Changes and Pretransitional Effects in Cholesteric Liquid Crystals
Authors: Voss J. , Sackmann E.
Published: February 2015

The effect of non-chiralic solute molecules on the pitch of cholesteric mixtures of cholesteryl chloride and cholesteryl nonanoate has been studied as a function of the composition and the temperature. The occurrence of a pretransition to the smectic state at low CC content is established. In the pretransitional state the pitch decreases exponentially with increasing temperature and is extremely sensitive against the addition of most organic molecules. In the normal cholesteric state the pitch increases with increasing temperature. In this state only a very limited number of nonchiralic molecules exert an appreciable influence on the pitch.
Notizen: The Effect Reciprocal to Flow Birefringence in Cases
Authors: Hess S.
Published: February 2015

Flow birefringence in molecular gases is due to a collisional alignment (tensor polarization) of the rotational angular momentum of the molecules in the presence of a gradient of the flow velocity. The reciprocal phenomenon is an anisotropy of the velocity distribution caused by an externally maintained tensor polarization. The kinetic theory of this new effect is presented and methods for its experimental detection are indicated.
An Approach to a Discrete Quantum Mechanics in Closed Riemannian Spaces
Authors: Halpern Leopold
Published: February 2015

Quantum mechanics is contemplated in closed Riemannian spaces where the momentum spectrum is discrete. The theory formulated in this case is equivalent to an exclusively discrete scheme; continuity occurs only statistically. The operators corresponding to the dynamical variables are determined and the uncertainity relation is examined. Agreement is obtained in the local limit with quantum mechanics as formulated in flat space within the experimental accuracy.
107Ag and 109Ag Nuclear Magnetic Resonance Studies of Ag+ Ions in Aqueous Solutions
Authors: Burges C.-W. , Koschmieder R. , Sahm W. , Schwenk A.
Published: February 2015

The NMR lines of 107Ag and 109Ag have been investigated in aqueous solutions of AgF, AgNO3, and AgClO4. The ratio of the Larmor frequencies of 109Ag and 107Ag has been measured in various samples: ν(109Ag)/ν(107Ag) = 1.149 639 7 (8). No primary isotopic effect was to be detected within these limits of error (0.7 ppm). This ratio yields the hyperfine structure anomaly 107⊿109 = − 0.004127 7(7). The concentration dependence of the chemical shift of the 107Ag and 109Ag resonance frequencies was determined. Using this dependence, the ratios of the Larmor frequencies of the 107Ag and 109Ag nuclei for infinite dilution relative to the resonance frequency of 73Ge in GeCl4 are given. The magnetic moments of the 107Ag+ and 109Ag+ ions merely surrounded by water molecules are μ(107Ag+) = − 0.113 045 3(9) μN and μ(109Ag+) = − 0.129 961 5(10) μN without diamagnetic corrections. These values are compared with the result of an atomic beam experiment, the difference of the moments is due to the shielding of the silver nuclei by water molecules around the ions. The shielding constant is σ* (Ag+ in H2O vs. Ag atom) = − 0.000 94(17). Preliminary values of the relaxation times are given.
Utilization of Canonical Transformations for the Vibronic Self-Energies of Coupled Impurity Centers
Authors: Kristoffel N. N. , Sigmund E. , Wagner M.
Published: February 2015

The self-energies of a system of two electronically coupled impurity centers, one of which inter-acts with the vibrations of the surrounding crystal (Fano system), are derived by use of non-linear canonical transformations. The regions of applicability of this method are discussed and the results compared with those derived by Green’s function techniques in an earlier paper of one of the authors (N. N. K.). The self-energies calculated up to second order have a very simple form and exhibit the correct behaviour also in regions where the results of the Green’s function method are no longer valid.
Experimentelle Untersuchungen zur Stark-Verbreiterung der Balmer-Linien Hα und Hβ / Experimental Investigation of the Stark Broadening of the Balmer Lines Hα and Hβ
Authors: Ehrich Horst , Kusch Hans Jürgen
Published: February 2015

The profiles of the Stark broadened Balmer lines Hα and Hβ have been measured in a wide range of temperature and electron density. By the use of different light sources (3 wallstabilized arcs of different design, a pulsed discharge tube and a plexiglass-capillary discharge) the range was ex- tended to 1.0·104≦T≦3.2·104 °K for the plasma temperature and to 1·1016≦ne≦55·1016 cm−3 for the electron density in the Hβ-scale. The experimental profiles of the Hα-line agree with generalized impact approximations if the condition: ne
2/3/T>2·107 cm−2 grad−1 is fulfilled. Disagreements between the Hα and Hβ electron density scale can be removed applying an empirical correction-factor to the electron density obtained from the half-width of Hα.