bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exogenous Arachidonate Restores the Dimethoate‐Induced Inhibition of Steroidogenesis in Rat Interstitial Cells
Authors: Astiz Mariana , Hurtado de Catalfo Graciela , J. T. de Alaniz María , Marra Carlos Alberto 
Published: April 2012

AbstractThe present work studies the potential restorative effect of polyunsaturated fatty acids (PUFA, 5 μM/24 h) on the dimethoate (DMT)‐induced inhibition of testosterone biosynthesis in Leydig cells isolated from rat testes. Various fatty acids (FA) from the n‐6 (18:2, 20:3, 20:4, 22:4 and 22:5) and n‐3 (18.3, 20:5, 22:5, 22:6) series were assayed in Leydig cells, alone (as delipidated BSA complexes) and in combination with DMT (1 ppm). The n‐6 FA stimulated lipid peroxidation (LPO) and inhibited the activities of steroidogenic enzymes (3β‐ and 17β‐hydroxysteroid dehydrogenases). The n‐3 FA exerted an anti‐oxidant effect, decreasing the production of thiobarbituric‐acid reactive substances (TBARS) and inhibiting phospholipase A2 activity. The biosynthesis of testosterone in DMT‐treated cultures was completely normalized by ARA (20:4n‐6) and partially restored by the addition of 20:3n‐6, increasing ARA content inside the mitochondria. The other FA assayed failed to restore androgenesis. COX‐2 protein and prostaglandin F2α and E2 production were stimulated by 20:3n‐6, ARA, 18:3n‐3 and 20:5 n‐3. COX‐2 protein decreased upon addition of 22:5n‐3 and 22:6n‐3. StAR protein was increased by ARA and partially increased by 20:3n‐6, likely due to its metabolic conversion into ARA. Both FA increased the mitochondrial cholesterol pool available for testosterone biosynthesis. The rate of androgenesis is likely the result of various regulatory factors acting concomitantly on the physiology of Leydig cells.
Analyzing the scalability of coordination requirements of a distributed software project
Authors: de Souza Cleidson R. B. , Costa Jean M. R. , Cataldo Marcelo 
Published: April 2012

AbstractCollaborative tools have been proposed to support different domains, including software development. Despite important previous work on the design of collaborative tools, none directly addresses the required scalability of these collaborative tools. As such, the design of these tools is hindered because it does not take into account real-world requirements for handling and presenting information to support collaborative activities. In this paper, we use an approach to compute the coordination requirements of an actor, and by so doing, we are able to identify the required scalability of the collaborative tools to support these actors. The coordination requirements are the likely set of actors that a particular individual might need to coordinate/communicate with. We computed the coordination requirements of software developers involved in a large-scale distributed software development project. Software developers’ coordination requirements were computed in four different time intervals: 1, 7, 15, and 30 days so that we could assess the scalability of collaborative tools in both short and long term software development activities. Our results suggest that, in some cases, the number of coordination requirements of a given actor might be very large, and that current collaborative software development tools do not provide proper support for such values. Furthermore, we observed that coordination requirements often involved members of different teams and from different locations, which increases the importance of having collaborative tools properly designed, given the difficulty of collaborating across organizational and geographical boundaries.
Third-order theory for multi-directional irregular waves
Authors: Madsen Per A. , Fuhrman David R. 
Published: April 2012

AbstractA new third-order solution for multi-directional irregular water waves in finite water depth is presented. The solution includes explicit expressions for the surface elevation, the amplitude dispersion and the vertical variation of the velocity potential. Expressions for the velocity potential at the free surface are also provided, and the formulation incorporates the effect of an ambient current with the option of specifying zero net volume flux. Harmonic resonance may occur at third order for certain combinations of frequencies and wavenumber vectors, and in this situation the perturbation theory breaks down due to singularities in the transfer functions. We analyse harmonic resonance for the case of a monochromatic short-crested wave interacting with a plane wave having a different frequency, and make long-term simulations with a high-order Boussinesq formulation in order to study the evolution of wave trains exposed to harmonic resonance.
Organ-specific exposure and response to sulforaphane, a key chemopreventive ingredient in broccoli: implications for cancer prevention
Authors: Veeranki Omkara L. , Bhattacharya Arup , Marshall James R. , Zhang Yuesheng 
Published: April 2012

Naturally occurring sulforaphane (SF) has been extensively studied for cancer prevention. However, little is known as to which organs may be most affected by this agent, which impedes its further development. In the present study, SF was administered to rats orally either in a single dose or once daily for 7 d. Tissue distribution of SF was measured by a HPLC-based method. Glutathione S-transferase (GST) and NAD(P)H:quinone oxidoreductase 1 (NQO1), two well-known cytoprotective phase 2 enzymes, were measured using biochemical assays to assess tissue response to SF. SF was delivered to different organs in vastly different concentrations. Tissue uptake of SF was the greatest in the stomach, declining rapidly in the descending gastro-intestinal tract. SF was rapidly eliminated through urinary excretion, and urinary concentrations of SF equivalents were 2–4 orders of magnitude higher than those of plasma. Indeed, tissue uptake level of SF in the bladder was second only to that in the stomach. Tissue levels of SF in the colon, prostate and several other organs were very low, compared to those in the bladder and stomach. Moreover, induction levels of GST and NQO1 varied by 3- to 6-fold among the organs of SF-treated rats, though not strictly correlated with tissue exposure to SF. Thus, there is profound organ specificity in tissue exposure and response to dietary SF, suggesting that the potential chemopreventive benefit of dietary SF may differ significantly among organs. These findings may provide a basis for prioritising organs for further chemopreventive study of SF.
The Smaller the Market, the Better the Rent Capturing: Electrification in North Portugal during the Interwar Period
Authors: Rodríguez Isabel Bartolomé 
Published: April 2012

AbstractThis article analyses the origin of the persistently high level of electricity prices that hampered the expansion of electricity consumption during the interwar period in Porto. Initially, the rent-seeking behaviour of both the supply firm and the City Hall at the local level affected the expansion of the local electricity market. During the 1930s, this collusion at municipal level coincided with unpredictable energy policies at state level. This circumstance impeded the indispensable increase of scale and the building of a regional market of electricity in north Portugal. The literature on regulation and institutional analysis has proved very useful. Finally, though equally important, primary sources from company archives and institutional bodies were also employed.
Adverse selection and moral hazard in the provision of clinical trial ancillary care
Authors: Richards Michael R. , Helmchen Lorens A. 
Published: April 2012

AbstractAs more and more clinical trials are conducted in developing countries, concerns arise about non-trial medical care available to study participants. Recent work argues for ancillary care – medical care not part of the clinical trial per se – to be formally incorporated into these studies. Although the provision of ancillary care is often justified on ethical grounds, a number of crucial implementation issues remain unresolved, including its scope, duration and financing. Drawing on lessons from health insurance benefit design, we highlight two overlooked challenges for ancillary care adoption – adverse selection and moral hazard – and offer recommendations that could attenuate their consequences. Specifically, adverse selection and moral hazard could be reduced by offering a choice between ancillary medical care and monetary compensation or rewarding low ancillary care utilization. Alternatively, researchers’ financial risk due to ancillary care could be shifted to a third-party insurer. Recognizing participants’ behavioral responses to prospective offers of ancillary medical care would allow funders and research teams to forecast the demand for ancillary care more accurately and to prepare for its provision more adequately.
Magnetic conjugacy of northern and southern auroral beads
Authors: Motoba Tetsuo , Hosokawa Keisuke , Kadokura Akira , Sato Natsuo 
Published: April 2012

Auroral beads, i.e., azimuthally arrayed bright spots resembling a pearl necklace, have recently drawn attention as a possible precursor of auroral substorms. We used simultaneous, ground‐based, all‐sky camera observations from a geomagnetically conjugate Iceland‐Syowa Station pair to demonstrate that the auroral beads, whose wavelength is ∼30–50 km, evolve synchronously in the northern and southern hemispheres and have remarkable interhemispheric similarities. In both hemispheres: 1) they appeared almost at the same time; 2) their longitudinal wave number was similar ∼300–400, corresponding bead separation being ∼1° in longitude; 3) they started developing into a larger scale spiral form at the same time; 4) their propagation speeds and their temporal evolution were almost identical. These interhemispheric similarities provide strong evidence that there is a common driver in the magnetotail equatorial region that controls the major temporal evolution of the auroral beads; thus, the magnetosphere plays a primary role in structuring the initial brightening arc in this scale size.
Life Tables of Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae): with a Mathematical Invalidation for Applying the Jackknife Technique to the Net Reproductive Rate
Authors: Chi Hsin , Huang Yu-Bing 
Published: April 2012

AbstractLife table data for the melon fly, Bactrocera cucurbitae (Coquillett), reared on cucumber (Cucumis sativus L.) were collected under laboratory and simulated field conditions. Means and standard errors of life table parameters were estimated for two replicates using the jackknife technique. At 25ºC, the intrinsic rates of increase (r) found for the two replicates were 0.1354 and 0.1002 day-1, and the net reproductive rates (R~0~) were 206.3 and 66.0 offspring, respectively. When the cucumbers kept under simulated field conditions were covered with leaves, the r and R~0~ for the two replicates were 0.0935 and 0.0909 day-1, 17.5 and 11.4 offspring, respectively. However, when similar cucumbers were left uncovered, the r and R~0~ for the two replicates were 0.1043 and 0.0904 day-1, and 27.7 and 10.1 offspring, respectively. Our results revealed that considerable variability between replicates in both laboratory and field conditions is possible; this variability should be taken into consideration in data collection and application of life tables. Mathematical analysis has demonstrated that applying the jackknife technique results in unrealistic pseudo-R~0~ and overestimation of its variance. We suggest that the jackknife technique should not be used for the estimation of variability of R~0~.
A Systems Biology Approach towards Deciphering the Unfolded Protein Response in Huntington's Disease
Authors: Ayasolla Kameshwar , Kalathur Ravi , Futschik Matthias 
Published: April 2012

AbstractAlthough the disease causing gene huntingtin has been known for some time, the exact cause of neuronal cell death during Huntington's disease (HD) remains unknown. One potential mechanism contributing to the massive loss of neurons in HD brains might be the Unfolded Protein Response (UPR) which is activated by accumulation of misfolded proteins in the endoplasmic reticulum (ER). As an adaptive response, UPR upregulates transcription of chaperones, temporarily attenuating new translation and activates protein degradation via the proteasome. However, at high levels of ER stress, UPR signalling can contribute to neuronal apoptosis.Our primary aims include (a) construction of the UPR signalling network, (b) curation and bioinformatical identification of UPR target genes and finally (c) examination of HD gene expression data sets for UPR transcriptional signatures and differential regulation of UPR pathways.The UPR signalling pathway is reconstructed based on literature review and using the "Unified Interactome database":http://www.unihi.org. Lists of UPR target genes detected by previous experiments or as predicted by computational analysis are compiled. This allows us to perform enrichment analysis for differential HD gene expression and to assess whether UPR expression signatures are prominent during HD pathogenesis.
Results:
The canonical UPR pathway is complemented with additional protein interaction data allowing us to assess its embedding into the cellular context and to identify potential modifiers as well as novel drug targets.

Conclusions:
The in depth systems biology analysis can give us valuable insights about the involvement of the UPR in HD.
Structure based de novo design of IspD inhibitors as anti-tubercular agents
Authors: Varikoti Rohith Anand , Gangwal Rahul , Dhoke Gaurao , Ramaswamy Venkata Krishnan , Sangamwar Abhay 
Published: April 2012

AbstractTuberculosis is one of the leading contagious diseases, caused by Mycobacterium tuberculosis. Despite improvements in anti-tubercular agents, it remains one of the most prevalent infectious diseases worldwide, responsible for a total of 1.6 million deaths annually. The emergence of multidrug resistant strains highlighted the need of discovering novel drug targets for the development of anti-tubercular agents. 2-C-methyl-D-erythritol-4-phosphate cytidyltransferase (IspD) is an enzyme involved in MEP pathway for isoprenoid biosynthesis, which is considered an attractive target for the discovery of novel antibiotics for its essentiality in bacteria and absence in mammals. In the present study, we have employed structure based drug design approach to develop novel and potent inhibitors for IspD receptor. To explore binding affinity and hydrogen bond interaction between the ligand and active site of IspD receptor, docking studies were performed. ADMET and synthetic accessibility filters were used to screen designed molecules. Finally, ten compounds were selected and subsequently submitted for the synthesis and in vitro studies as IspD inhibitors.
Lateral Mass Fixation in Subaxial Cervical Spine: Anatomic Review
Authors: Mohamed Elrahmany , Ihab Zidan , Moaz Anwar , Ayman Nabawi , Haitham Abo-elw 
Published: April 2012

Introduction The cervical spine is a highly mobile segment of the spinal column, liable to a variety of diseases and susceptible to trauma. It is a complex region where many vital structures lie in close proximity. Lateral mass screw fixation has become the method of choice in stabilizing subaxial cervical spine among other posterior cervical fixation techniques whenever the posterior elements are absent or compromised. Objective This study examined cervical specimens of cadavers and cervical computed tomography (CT) scans to minimize as much as possible complications of cervical lateral mass screw placement such as vertebral artery or nerve root injuries, facet joint violations, or inadequate placement. Methods Forty normal cervical CT scans, obtained from the emergency unit as part of the trauma workup, were included in this study plus 10 cervical cadaveric specimens obtained from the Alexandria Neuro-anatomy laboratory. There were three fixed parameters for screw insertion in this study. First, the point of screw insertion was the midpoint of the lateral mass; it was the crossing point between the sagittal and axial planes of the posterior cortex of the lateral mass. Second, the direction of the screw in the craniocaudal plane was 30 degrees cranially to avoid facet joint penetration. Third, the exit point of the screw was located on the ventral cortex of the lateral mass just lateral to the root of the transverse process in the midaxial cut of each lateral mass, to make a sound bicortical fixation without injuring the vertebral artery or the nerve root. The selected screw trajectory in this study was the line drawn between the inlet and exit points. The depth and width of the lateral mass of the cervical vertebrae from C3 to C7 were measured as well as the angle of screw trajectory from the sagittal plane. All these measures were applied on the cadaveric specimens to make sure that no injury to the vertebral artery, nerve root, or facet joint occurred. Results As regards the collected measurements of the lateral mass of all subaxial cervical vertebrae, the study revealed that the average depth of the lateral mass was 12.83 ± 1.28 mm. The average width of the lateral mass was 11.92 ± 0.96 mm. The average divergent angle of bicortical screw insertion without injury to the vertebral artery or the nerve root was 19.51 ± 1.83 degrees. As regard the cadaveric specimens, based on all the collected measurements taken from the CT scans, there was no reported injury to the vertebral arteries or nerve roots or penetration to the facet joints. Conclusion Lateral mass fixation can be applied easily and safely for all levels of subaxial cervical spine from C3 to C6 with the following parameters: (1) the point of entry is the midpoint of the lateral mass; (2) the screw trajectory is directed 30 degrees cranially and 20 degrees laterally; (3) the screw length is 13 to 15 mm.
Structural transformation and improved dielectric and magnetic properties in Ti-substituted Bi0.8La0.2FeO3 multiferroics
Authors: Reetu  , Agarwal Ashish , Sanghi Sujata , Ashima  , Ahlawat Neetu 
Published: April 2012

Abstract
Ti-substituted BiLaFeO3 ceramics having compositions Bi0.8La0.2Fe1−x
Ti
x
O3 (x = 0.0, 0.05, 0.1, 0.15) were synthesized by the conventional solid-state reaction method. Powder x-ray diffraction investigations performed at room temperature show that the crystal structure is rhombohedral for x = 0.0, 0.05; tetragonal for x = 0.15; and a phase boundary occurs at x = 0.1. In the Rietveld refinement good agreement between the observed and calculated pattern was observed. Dielectric response of these samples was analysed in the frequency range 1 kHz–5 MHz at different temperatures. A decrease in the values of real (ε′) and imaginary (ε″) parts of dielectric constant with Ti substitution indicates reduced conductivity and hence enhanced resistivity in doped samples. Stability of dielectric constant and conductivity with temperature is considerably improved with Ti substitution. Magnetic measurements were carried out at room temperature up to a field of 20 kOe. Magnetic properties of Bi0.8La0.2FeO3 ceramics are considerably improved on Ti substitution along with a significant opening in the room temperature M–H hysteresis loop. Higher values of remanent magnetization (M
r) 0.1373 and 0.1487 emu g−1; coercivity (H
c) 4.856 and 5.904 kOe are observed for samples with x = 0.1 and 0.15, respectively. This is due to the structural phase transition from rhombohedral to tetragonal.
Ultra-wide bandwidth measurement of partial discharge current pulses in SF6
Authors: Reid A J , Judd M D 
Published: April 2012

Abstract
This paper presents ultra-wide bandwidth measurements of partial discharge (PD) current pulses. Using a 33 GHz bandwidth oscilloscope together with a direct, matched coaxial connection to the PD source, pulses have been characterized with a greater degree of accuracy than has previously been achieved, with a minimum observed rise time of 24 ps. The PD source consists of a sharp protrusion in pressurized sulfur hexaflouride (SF6) with a tip radius of 25 µm. Both positive and negative corona pulses were recorded, revealing previously indistinguishable frequency content and features such as the appearance of groups of multiple component pulses occurring within a nanosecond time scale. The upper bandwidth limitation of the complete measurement set-up was established. This was calculated by cross-correlating current pulses with corresponding pulses filtered at lower frequencies to determine their similarity. The tendency for multiple consecutive pulses to occur within a short time period was evident. The results provide valuable data for researchers investigating fundamental physical phenomena of SF6 ionization and PD activity.
Ordering and segregation in isolated Au–Pd icosahedral nanoclusters and nanowires and the consequences of their encapsulation inside carbon nanotubes
Authors: Zhu B , Wang Y , Atanasov I S , Cheng D , Hou M 
Published: April 2012

Abstract
Metropolis Monte Carlo sampling in the semi-grand canonical ensemble with empirical potentials is used to predict equilibrium ordered structures and segregation properties of small icosahedral Au–Pd nanoclusters and helical nanowire segments over the whole range of compositions at low temperatures. The cases of free-standing clusters and wires are compared with the same systems encapsulated in carbon nanotubes.
A number of chemically ordered structures and segregation states are identified and found to be consistent with the same interplay between size mismatch, mixing enthalpy and surface energies of elemental metals which determines the thermodynamic equilibrium of binary metal alloys. Encapsulation has the effect of modifying the surface energies of nanoclusters and wires, with considerable consequences on their thermodynamic states, although the metal–graphite interaction strength is low as compared with the metal cohesive energy and the carbon–carbon binding energy.