bluuebunny/crossref_metadata_2025 huggingface dataset:
Graph isomorphic discrete partially ordered sets and semimodularity
Authors: Csontóová Mária , Lihová Judita
Published: February 2010

In [RATANAPRASERT, C.—DAVEY, B.: Semimodular lattices with isomorphic graphs, Order 4 (1987), 1–13], the authors found conditions under which an isomorphism of graphs of discrete lattices transfers semimodularity. The main theorem of the present paper generalizes their result for discrete partially ordered sets.
On quasi-prime, weakly quasi-prime left ideals in ordered-Γ-semigroups
Authors: Hila Kostaq
Published: February 2010

In this paper we obtain and establish some important results in ordered Γ-semigroups extending and generalizing those for semigroups given in [PETRICH, M.: Introduction to Semigroups, Merill, Columbus, 1973] and for ordered semigroups from [KEHAYOPULU, N.: On weakly prime ideals of ordered semigroups, Math. Japon. 35 (1990), 1051–1056], [KEHAYOPULU, N.: On prime, weakly prime ideals in ordered semigroups, Semigroup Forum 44 (1992), 341–346] and [XIE, X. Y.—WU, M. F.: On quasi-prime, weakly quasi-prime left ideals in ordered semigroups, PU.M.A. 6 (1995), 105–120]. We introduce and give some characterizations about the quasi-prime and weakly quasi-prime left ideals of ordered-Γ-semigroups. We also introduce the concept of weakly m-systems in ordered Γ-semigroups and give some characterizations of the quasi-prime and weakly quasi-prime left ideals by weakly m-systems.
On a partial syntactical criterion for the left distributivity and the idempotency
Authors: Jedlička Přemysl
Published: February 2010

We study here so called cuts of terms and their classes modulo the identities of the left distributivity and the idempotency. We give an inductive definition of such classes and this gives us a criterion that decides in some cases whether two terms are equivalent modulo both identities.
Generalized difference sequence space defined by |$$
\bar N
$$, p
k| summability and an Orlicz function in seminormed space
Authors: Bhardwaj Vinod , Bala Indu
Published: February 2010

The object of this paper is to introduce a new difference sequence space which arise from the notions of |$$
\bar N
$$, p
k| summability and an Orlicz function in seminormed complex linear space. Various algebraic and topological properties and certain inclusion relations involving this space have been discussed. This study generalizes results: [ALTIN, Y.—ET, M.—TRIPATHY, B. C.: The sequence space |$$
\bar N_p
$$|(M, r, q, s) on seminormed spaces, Appl. Math. Comput. 154 (2004), 423–430], [BHARDWAJ, V. K.—SINGH, N.: Some sequence spaces defined by |$$
\bar N
$$, p
n| summability, Demonstratio Math. 32 (1999), 539–546] and [BHARDWAJ, V. K.—SINGH, N.: Some sequence spaces defined by |$$
\bar N
$$, p
n| summability and an Orlicz function, Indian J. Pure Appl. Math. 31 (2000), 319–325].
Theorems for generalized Favard-Kantorovich and Favard-Durrmeyer operators in exponential function spaces
Authors: Nowak Grzegorz , Sikorska-Nowak Aneta
Published: February 2010

We consider the Kantorovich and the Durrmeyer type modifications of the generalized Favard operators and we prove some direct approximation theorems for functions f such that w
σ
f ∈ L
p(R), where 1 ≤ p ≤ ∞ and w
σ(x) = exp(−σx
2), σ > 0.
Elements Influencing Study Success
Authors: Jereb Eva
Published: February 2010

Elements Influencing Study Success

Study success can be influenced by following factors: (i) social elements (social class position, parents' education, parents' profession, parents' income); (ii) student-related factors (motivation, aptitude, effort, IQ, time spend on study, opportunity to learn, pre-university education); (iii) quality of instruction (organisation, course material, communication, assignments, exams, grading, course outcomes); (iv) curriculum (number of courses, sequence of courses, test schedule, system-block or parallel); (v) government (grant, student accommodation). In the paper the influence of these factors on study success is presented. Social and academic integration are central aspects. In the research we found out that "social elements" greatly influence the decision to enrol, but have less influence on marks received and the duration of study. Grants also greatly influence study success. We were surprised when we found out that factors from the "quality of instruction" group can only explain 12.3% of the variance of exam results.
Teaching Scrum in Cooperation with a Software Development Company
Authors: Mahnič Viljan , Georgiev Strahil , Jarc Tomo
Published: February 2010

Teaching Scrum in Cooperation with a Software Development Company

The increasing use of agile methods for software development creates the need for these methods to become part of the education of future computer and information science engineers. On the other hand, teaching these methods gives us an opportunity to verify individual agile concepts and their effectiveness. For that reason, project work is an appropriate and frequently used form of teaching that enables students to get acquainted with agile methods and, at the same time, provides case studies for evaluating individual agile concepts. We describe our approach to teaching the Scrum agile method, within the software technology course, in cooperation with a software development company. Students were taught through work on a real project for which a list of requirements was submitted by the company. A co-worker of this company participated throughout the teaching period playing the role of customer's representative. During their work, students consistently used the Scrum method and at the end of each iteration they evaluated their experience by means of a questionnaire. In the article, the Scrum method is presented first, then a description of work on the project is given and finally the results of the survey are described.
Stakeholder Approach and the Corporate Financial Performance
Authors: Blažek Ladislav , Částek Ondřej
Published: February 2010

Stakeholder Approach and the Corporate Financial Performance

The following paper aims to describe the analysis and utilization of stakeholder approach, which was used in the research of the Research Centre for Competitiveness of Czech Economy. The stakeholder model was employed in the research to explain the behavior of enterprises and to find factors of competitiveness. Here we can find assessment of stakeholders' importance and its relationship to corporate financial performance with some chosen interfering factors, which is preceding step before assessment all potential factors of competitiveness using multi dimensional analysis. Also the achieved results are related to chosen international and Czech studies.
A snow sensor experiment in Dronning Maud Land, Antarctica
Authors: Granberg Hardy B. , Cliche Patrick , Mattila Olli-Pekka , Kanto Eija , Leppäranta Matti
Published: February 2010

In January 2000 nine snow sensors were deployed in Dronning Maud Land, Antarctica, along a 355 km transect from Kvitkuven near the shelf edge via the Finnish research station, Aboa, to the Amundsenisen plateau. The purpose was to test a sensor system for spatio-temporal variations in temperature across the snow–air interface and snow accumulation/ablation, which includes atmospheric net balance and migrating snow dunes. In the dry snow conditions, environmental static electricity interfered with data transfer; several sensors were disabled early, while the longest record reached 6 months. Along the main transect, the year 2000 mass balance ranged from 52 to 221 mm w.e., largely following spatial patterns seen by other researchers. The level increased toward the edge of the ice sheet; unloading of drifting snow as the slope flattens, rather than increased snowfall as previously thought, may be responsible for this. At the Högisen ice dome site the mass balance was 897 mm w.e., possibly due to unloading of wind-blown snow, as katabatic winds are locally forced uphill. This mechanism is important to maintain such topographic features along the Antarctic ice sheet margin. Major precipitation events occurred at 3–5 week intervals and much of the precipitation fell before mid-June. The daily signal in temperature disappeared after the autumn equinox, then the spectrum displayed a broad peak at synoptic frequencies. Potential temperature decreased towards the shelf edge, displaying a pattern consistent with strong inversions and suggesting that strong evaporative cooling is associated with the katabatic winds.
Dynamics of a small surge-type glacier using one-dimensional geophysical inversion
Authors: De Paoli Laetitia , Flowers Gwenn E.
Published: February 2010

We investigate the dynamics of a small surge-type valley glacier as part of a study to characterize glacier response to climate in the Donjek Range, southwest Yukon, Canada. Pole displacements were measured using kinematic GPS techniques during three consecutive summer field seasons. Measured surface velocities range from <10 m a−1over the lower 1500 m of the 5 km long glacier to a maximum of ∼25–35 m a−1over the upper 3500 m. Basal velocities along an approximate flowline are reconstructed from the measured surface velocities using inverse methods. Control tests are used to validate the inversion scheme, and sensitivity tests are performed to evaluate the influence of the flow-law coefficient, shape factor and longitudinal averaging length. Inversion of the real data shows that basal motion accounts for 50–100% of the total surface motion along the flowline. Based on these results, and several other lines of evidence, we suggest this glacier may be undergoing a slow surge.
Terminus dynamics at an advancing glacier: Taku Glacier, Alaska
Authors: Truffer Martin , Motyka Roman J. , Hekkers Michael , Howat Ian M. , King Matt A.
Published: February 2010

Taku Glacier, Alaska, USA, is currently in the advance stage of the tidewater glacier cycle. We investigated the near-terminus dynamics by measuring surface velocities, surface elevation changes, ice thickness and ablation. Velocities vary on sub-daily, diurnal, seasonal and interannual timescales. Flowline modeling shows that the modeled surface velocities are sensitive to changes in till yield strength and thus effective basal pressures. The glacier bed deepens in the up-glacier direction and this imposes a minimum subglacial water pressure necessary for water to drain along the bed. In a simple model we impose water-pressure gradients based on phreatic surfaces of constant slopes to simulate the winter–summer transitions. This proves sufficient to explain an observed early-season switch from compressional to block flow. Velocities also vary between years. Changing basal conditions can result in lower horizontal velocities, which decrease the ice supply to the terminus and result in temporary surface lowering. But a decrease in ice flux to the terminus must lead to ice storage further upstream, and that ice mass will eventually reach the terminus. This can explain the observed episodic nature of terminus advance.
Sediment plume response to surface melting and supraglacial lake drainages on the Greenland ice sheet
Authors: Chu Vena W. , Smith Laurence C. , Rennermalm Asa K. , Forster Richard R. , Box Jason E. , Reeh Niels
Published: February 2010

Increased mass losses from the Greenland ice sheet and inferred contributions to sea-level rise have heightened the need for hydrologic observations of meltwater exiting the ice sheet. We explore whether temporal variations in ice-sheet surface hydrology can be linked to the development of a downstream sediment plume in Kangerlussuaq Fjord by comparing: (1) plume area and suspended sediment concentration from Moderate Resolution Imaging Spectroradiometer (MODIS) imagery and field data; (2) ice-sheet melt extent from Special Sensor Microwave/Imager (SSM/I) passive microwave data; and (3) supraglacial lake drainage events from MODIS. Results confirm that the origin of the sediment plume is meltwater release from the ice sheet. Interannual variations in plume area reflect interannual variations in surface melting. Plumes appear almost immediately with seasonal surface-melt onset, provided the estuary is free of landfast sea ice. A seasonal hysteresis between melt extent and plume area suggests late-season exhaustion in sediment supply. Analysis of plume sensitivity to supraglacial events is less conclusive, with 69% of melt pulses and 38% of lake drainage events triggering an increase in plume area. We conclude that remote sensing of sediment plume behavior offers a novel tool for detecting the presence, timing and interannual variability of meltwater release from the ice sheet.
Ice velocity and climate variations for Baltoro Glacier, Pakistan
Authors: Quincey D.J. , Copland L. , Mayer C. , Bishop M. , Luckman A. , Belò M.
Published: February 2010

The recent dynamic behaviour of Karakoram glaciers is expected to differ from that shown by glaciers in the central and eastern Himalaya because of regional variations in precipitation and temperature trends. However, there are insufficient quantitative data to support or confute such hypotheses. We present velocity data covering the period 1993–2008 for Baltoro Glacier, one of the longest glaciers in the Karakoram. Velocity measurements were made using cross-correlation feature tracking applied to European Remote-sensing Satellite (ERS-1 and -2) and Envisat advanced synthetic aperture radar (ASAR) data, supplemented by differential global positioning system (DGPS) measurements. We find a gradual acceleration of the glacier during the early 2000s, in particular during winter months. Multi-seasonal data reveal a large difference between summer and winter flow characteristics, but only in the upper ablation zone. Summer 2005 was a particularly dynamic period following from the heavy winter snowfall of 2004, indicating the importance of basal meltwater availability for glacier flow. Transverse velocity profiles indicate that Baltoro Glacier undergoes ‘block’ flow across much of the upper ablation zone during the summer, which we interpret as evidence of widespread basal sliding. The DGPS data confirm the rapid increase in flow detected during 2005. Modelled climatic data reveal decreasing summer temperatures and increasing precipitation over the study period, helping to explain the observed dynamic variations and their differences from glaciers elsewhere in the Himalaya.
Towards radiocarbon dating of ice cores
Authors: Sigl M. , Jenk T.M. , Kellerhals T. , Szidat S. , Gäggeler H.W. , Wacker L. , Synal H.-A. , Boutron C. , Barbante C. , Gabrieli J. , Schwikowski M.
Published: February 2010

A recently developed dating method for glacier ice, based on the analysis of radiocarbon in carbonaceous aerosol particles, is thoroughly investigated. We discuss the potential of this method to achieve a reliable dating using examples from a mid- and a low-latitude ice core. Two series of samples from Colle Gnifetti (4450 m a.s.l., Swiss Alps) and Nevado Illimani (6300 m a.s.l., Bolivian Andes) demonstrate that the 14C ages deduced from the water-insoluble organic carbon fraction represent the age of the ice. Sample sizes ranged between 7 and 100 μg carbon. For validation we compare our results with those from independent dating. This new method is thought to have major implications for dating non-polar ice cores in the future, as it provides complementary age information for time periods not accessible with common dating techniques.
The Historical Ecology of Human and Wild Primate Malarias in the New World
Authors: Cormier Loretta A.
Published: February 2010

The origin and subsequent proliferation of malarias capable of infecting humans in South America remain unclear, particularly with respect to the role of Neotropical monkeys in the infectious chain. The evidence to date will be reviewed for Pre-Columbian human malaria, introduction with colonization, zoonotic transfer from cebid monkeys, and anthroponotic transfer to monkeys. Cultural behaviors (primate hunting and pet-keeping) and ecological changes favorable to proliferation of mosquito vectors are also addressed.
Tourism as an Interpretive and Mediating Influence: A Review of the Authority of Guidebooks in Protected Areas
Authors: Wearing Stephen L. , Whenman Amy E.
Published: February 2010

This short review seeks to present the outcomes of a study that examined the potential effectiveness of guidebooks as a form of interpretation in reducing environmental impacts in a national park. In it, Wearing and Whenman provide a review based on information gained from interviews
with 29 trekkers undertaking the Overland Track in Tasmania, Australia. Results from the interviews where correlated with the literature and indicate that trekkers are more likely to use guidebooks at the planning stage of a trek in order to make decisions about what area to visit, what equipment
to take, transport, and accommodation. The guidebooks used by trekkers in this inquiry were found to have only a small amount of information on minimal impact messages and such messages were found to be poorly structured. As a result, guidebooks were found to have little influence in mediating
responsible environmental behavior in protected areas. The study recommends that well-structured minimal impact messages be incorporated into guidebooks using the Elaboration Likelihood Model of attitude change and persuasion to direct the process. Readers of Tourism Analysis are encouraged
to reflect upon how the guidebooks available in their own tourism/tourist arenas strongly influence or undersuspectingly mediate what is there.
Advocacy: It Is Time to Be the Change
Authors: McCracken Ann L.
Published: February 2010

Nursing is well positioned to be a major force in informing and influencing health policy. Gerontological nurses, as essential stakeholders in health care policy, must be sensitive to policy windows, seek out resources, design systematic approaches, and take action that will shape more effective and efficient care for the older people they serve.
IL-17 Contributes to Angiogenesis in Rheumatoid Arthritis
Authors: Pickens Sarah R. , Volin Michael V. , Mandelin Arthur M. , Kolls Jay K. , Pope Richard M. , Shahrara Shiva
Published: February 2010

Angiogenesis is an early and a critical event in the pathogenesis of rheumatoid arthritis (RA). Neovascularization is dependent on endothelial cell activation, migration and proliferation, and inhibition of angiogenesis may provide a novel therapeutic approach in RA. In this study, we document a novel role of IL-17 in mediating angiogenesis. Local expression of IL-17 in mouse ankles increases vascularity. We further demonstrate that IL-17 is angiogenic by showing its ability to promote blood vessel growth in Matrigel plugs in vivo. Additionally, IL-17, in concentrations present in the RA joint, induces human lung microvascular endothelial cell (HMVEC) migration mediated through the PI3K/AKT1 pathway. Furthermore, suppression of the PI3K pathway markedly reduces IL-17–induced tube formation. We also show that both IL-17–induced HMVEC chemotaxis and tube formation are mediated primarily through IL-17 receptor C. Neutralization of either IL-17 in RA synovial fluids or IL-17 receptor C on HMVECs significantly reduces the induction of HMVEC migration by RA synovial fluid. Finally, RA synovial fluid immunoneutralized with anti–IL-17 and antivascular endothelial growth factor does not reduce HMVEC migration beyond the effect detected by immunodepleting each factor alone. These observations identify a novel function for IL-17 as an angiogenic mediator in RA, supporting IL-17 as a therapeutic target in RA.
Pyrethroid insecticide concentrations and toxicity in streambed sediments and loads in surface waters of the San Joaquin Valley, California, USA
Authors: Domagalski Joseph L. , Weston Donald P. , Zhang Minghua , Hladik Michelle
Published: February 2010

Pyrethroid insecticide use in California, USA, is growing, and there is a need to understand the fate of these compounds in the environment. Concentrations and toxicity were assessed in streambed sediment of the San Joaquin Valley of California, one of the most productive agricultural regions of the United States. Concentrations were also measured in the suspended sediment associated with irrigation or storm-water runoff, and mass loads during storms were calculated. Western valley streambed sediments were frequently toxic to the amphipod, Hyalella azteca, with most of the toxicity attributable to bifenthrin and cyhalothrin. Up to 100% mortality was observed in some locations with concentrations of some pyrethroids up to 20 ng/g. The western San Joaquin Valley streams are mostly small watersheds with clay soils, and sediment-laden irrigation runoff transports pyrethroid insecticides throughout the growing season. In contrast, eastern tributaries and the San Joaquin River had low bed sediment concentrations (<1 ng/g) and little or no toxicity because of the preponderance of sandy soils and sediments. Bifenthrin, cyhalothrin, and permethrin were the most frequently detected pyrethroids in irrigation and storm water runoff. Esfenvalerate, fenpropathrin, and resmethrin were also detected. All sampled streams contributed to the insecticide load of the San Joaquin River during storms, but some compounds detected in the smaller creeks were not detected in the San Joaquin River. The two smallest streams, Ingram and Hospital Creeks, which had high sediment toxicity during the irrigation season, accounted for less than 5% of the total discharge of the San Joaquin River during storm conditions, and as a result their contribution to the pyrethroid mass load of the larger river was minimal. Environ. Toxicol. Chem. 2010;29:813–823. © 2010 SETAC
Assessment of estrogenic activity conducted by combining bioassay and chemical analyses of the effluent from wastewater treatment plants in Nanjing, China
Authors: Lu Guanghua , Zhang Haizhen , Wang Chao
Published: February 2010

The estrogenic activity of the effluent from three municipal wastewater treatment plants (WWTPs) in Nanjing, China, was investigated. The water samples were enriched by solid-phase extraction and then eluted with different polar solvents, which gave 11 fractionated extracts. Chemical analysis and a vitellogenin (Vtg) assay in goldfish (Carassias auratus) were then utilized to evaluate the estrogenic activities 7 d after a single injection of the effluent extracts of WWTPs and to identify causative agents that led to the induction of Vtg in male fish. The results reveal that Vtg induction occurred primarily in response to the 75 to 90% methanol extracts, and different concentrations of the natural estrogens estrone (E1) and 17β-estradiol (E2) were detected in these extracts. As the Vtg induction increased, the plasma E2 levels increased, and a correlation between Vtg and E2 does exist. Furthermore, the gonadal somatic index (GSI) did not decrease significantly (p > 0.05) when the Vtg concentrations were elevated after 7 d. Different concentrations of estrogens were detected in the effluents, which demonstrated that the current treatment processes employed by the three WWTPs could not fully remove these compounds. As a result, the aquatic organisms in the receiving water (Yangtze River) were at a risk of feminization. Environ. Toxicol. Chem. 2010;29:1279–1286. © 2010 SETAC
[3H]4‐(dimethylamino)‐N‐(4‐(4‐(2‐methoxyphenyl)piperazin‐1‐yl) butyl)benzamide: A selective radioligand for dopamine D3receptors. II. Quantitative analysis of dopamine D3and D2receptor density ratio in the caudate‐putamen
Authors: Xu Jinbin , Hassanzadeh Babak , Chu Wenhua , Tu Zhude , Jones Lynne A. , Luedtke Robert R. , Perlmutter Joel S. , Mintun Mark A. , Mach Robert H.
Published: February 2010

4‐(Dimethylamino)‐N‐(4‐(4‐(2‐methoxyphenyl)piperazin‐1‐yl)butyl)benzamide (WC‐10), aN‐phenyl piperazine analog, displays high affinity and moderate selectivity for dopamine D3receptors versus dopamine D2receptors (Chu et al. [2005] Bioorg Med Chem 13:77–87). In this study, WC‐10 was radiolabeled with tritium (specific activity = 80 Ci/mmol), and quantitative autoradiography studies were conducted using rhesus monkey and Sprague‐Dawley rat brain sections.Kdvalues for the binding of [3H]WC‐10 to D3receptors obtained from quantitative autoradiography with rhesus monkey and rat brain sections are in agreement withKdvalues obtained from cloned human and rat receptors (Xu et al. [2009] Synapse 63:717‐728). The D2selective antagonist [3H]raclopride binds with 11‐fold higher affinity to human HEK D2L(Kd= 1.6 nM) than HEK D3(Kd= 18 nM) receptors; [3H]raclopride binds to rat Sf9 rD2Lreceptors with aKdof 6.79 nM, a value that is 4‐fold lower than binding to human HEK D2Lreceptors and 2.5‐fold higher than binding to rat Sf9 rD3receptors. In vitro quantitative autoradiography studies with [3H]WC‐10 and [3H]raclopride were conducted on adult rat and rhesus monkey brain sections. A mathematical model for calculating the absolute densities of dopamine D2and D3receptors based on the in vitro receptor binding data of [3H]WC‐10 and [3H]raclopride was developed. Synapse 64:449–459, 2010. © 2010 Wiley‐Liss, Inc.
Expression of the NR2B‐NMDA receptor subunit and its Tbr‐1/CINAP regulatory proteins in postmortem brain suggest altered receptor processing in schizophrenia
Authors: Kristiansen Lars V. , Patel Sagar A. , Haroutunian Vahram , Meador‐Woodruff James H.
Published: February 2010

Several lines of evidence implicate aberrant glutamate neurotransmission in the pathophysiology of schizophrenia. In particular, compromised signaling through the N‐methyl‐D‐aspartate (NMDA) receptor has been linked to positive, negative, and cognitive symptoms of this illness. Studies in postmortem brain have identified altered expression of several structural and signaling molecules of the postsynaptic density (PSD), including the abundantly expressed protein PSD‐95, which binds directly to NR2 subunits of the NMDA receptor and regulates its trafficking, membrane expression, and downstream signaling. Several mechanisms for functional regulation of the NR2B‐containing NMDA receptor, which have been linked to cognitive dysfunction in schizophrenia, are well known. To analyze whether early events in NR2B processing are affected in schizophrenia, we have isolated a subcellular endoplasmic reticulum (ER)‐enriched fraction from postmortem brain and analyzed expression of the NR1 and NR2B NMDA receptor subunits as well as PSD‐95 in two areas of prefrontal cortex. We found significantly decreased ER expression of NR2B and PSD‐95 in dorsolateral prefrontal cortex in schizophrenia. Analysis in total‐cell homogenates from the same subjects of NR2B and PSD‐95 expression, as well as of the CINAP and Tbr‐1 transcription regulatory proteins, indicate that changes in NR2B processing in schizophrenia involve increased ER exit of NR2B containing NMDA receptors. Synapse 64:495–502, 2010. © 2010 Wiley‐Liss, Inc.
Surface Activity, Thermodynamics of Micellization and Adsorption Properties of Quaternary Salts Based on Ethanolamines and Decyl Bromide
Authors: Asadov Ziyafaddin H. , Rahimov Ravan A. , Nasibova Shafiga M. , Ahmadova Gulnara A.
Published: February 2010

The surface‐active properties of ionic‐liquid type salts synthesized by the interaction of ethanolamines and decyl bromide have been studied. Surface tension as a function of concentration of the surfactant in aqueous solution was measured at 10, 20, 30 and 40 °C using a drop volume stalagmometer. From these measurements, the maximum surface excess concentration and the minimum area per molecule at the aqueous solution/air interface, the critical micelle concentration (CMC), the surface pressure at the CMC, and the standard thermodynamic parameters of adsorption and micellization were calculated. The structural effects on adsorption, micellization, and the effectiveness of surface tension reduction are discussed in terms of these parameters.
Greater trochanteric preserving hip arthroplasty in the treatment of infantile septic arthritis: Long-term results
Authors: Abrishami Saeid , Karami Mohsen , Karimi Amin , Soufali Amir Payman , Aslani Hamid Reza , Badizadeh Kamran
Published: February 2010

Background

Balanced forces around the hip joint are critical for normal development of the hip joint, so it should be considered in every hip reconstructive procedure.

Methods

In seven children with complete destruction of the femoral head and neck due to septic arthritis, a reconstructive hip surgery was done to reconstruct the femoral head without sacrificing the greater trochanter and its muscles completely. The technique consists of a modified greater trochanter arthroplasty with only a medial portion of the greater trochanter and a varus femoral osteotomy.

Results

The average age of the children at surgery was 17 months (range 8–36 months) and the patients were followed for an average of 16.6 years (range 10.9–20.1 years). The average number of second operative procedures for each patient was 2 (range 1–4). The follow-up evaluation for each patient included documentation of pain, hip range of motion, and assessment of gait. In addition, the current leg-length discrepancy, final coverage and stability of the hip joint were documented. At final evaluation, all patients had a pain-free stable hip and two patients had near-normal hip range of motion. All patients have had satisfactory surgery results.

Conclusions

By this kind of hip reconstruction, we could provide a stable painless hip joint with special attention to the greater trochanter's role on hip biomechanics.
New design platform for malonyl‐CoA‐acyl carrier protein transacylase
Authors: Hong Seung Kon , Kim Kook Han , Park Joon Kyu , Jeong Ki-Woong , Kim Yangmee , Kim Eunice EunKyeong
Published: February 2010

Malonyl‐CoA‐acyl carrier protein transacylase (MCAT) transfers the malonyl group from malonyl‐CoA to holo‐acyl carrier protein (ACP), and since malonyl‐ACP is a key building block for fatty‐acid biosynthesis it is considered as a promising antibacterial target. The crystal structures of MCAT from Staphylococcus aureus and Streptococcus pneumoniae have been determined at 1.46 and 2.1 Å resolution, respectively. In the SaMCAT structure, the N‐terminal expression peptide of a neighboring molecule running in the opposite direction of malonyl‐CoA makes extensive interactions with the highly conserved “Gly‐Gln‐Gly‐Ser‐Gln” stretch, suggesting a new design platform. Mutagenesis results suggest that Ser91 and His199 are the catalytic dyad.
Cu,Zn‐superoxide dismutase is required for cell wall structure and for tolerance to cell wall‐perturbing agents in Saccharomyces cerevisiae
Authors: Liu Xiangyong , Zhang Xiaohua , Zhang Zhaojie
Published: February 2010

Here we report that deletion of SOD1, the Cu,Zn‐superoxide dismutase in Saccharomyces cerevisiae is sensitive to cell wall‐perturbing agents, such as Calcofluor white and Congo red. The sensitivity was restored by retransformation with wild type SOD1 or the addition of N‐acetylcysteine or reduced glutathione to the medium. Additionally, the accumulation of reactive oxygen species was observed in sod1Δ mutant in the presence of Calcofluor white or Congo red. Cell wall analysis indicated an increase of cell wall chitin and cell wall thickness in sod1Δ mutant compared to wild type. These results indicate a novel direct connection between antioxidative functions and cell wall homeostasis.
UV‐induced downregulation of the CDC25B protein in human cells
Authors: Lemaire Matthieu , Ducommun Bernard , Nebreda Angel R.
Published: February 2010

The CDC25B phosphatase regulates the activation of CDK1–Cyclin B at the onset of mitosis, being a key target of the checkpoint pathways activated by cellular stress and DNA damage. Previous work has reported that checkpoint activation induces the sequestration of CDC25B in the cytoplasm. Here we show that in response to UV irradiation, the levels of CDC25B protein can be downregulated independently of classical checkpoints pathways such as p53, ATM/ATR and p38 MAPK. We also show that translational repression mediated by eIF2α phosphorylation regulates CDC25B expression levels. Taken together, our results illustrate a new mechanism of CDC25B regulation in response to stress.
Supplier innovativeness, organizational learning styles and manufacturer performance: An empirical assessment
Authors: Azadegan Arash , Dooley Kevin J.
Published: February 2010

Suppliers have become an increasingly important source of product and process innovation. While case studies have documented how supplier innovation can benefit a manufacturer, this relationship has not been empirically validated, nor have contingencies been explored. Using organizational learning theory we posit that the link between supplier innovativeness and manufacturer performance is moderated by the “fit” between the learning styles of the manufacturer and supplier. We empirically test our hypotheses using hierarchical linear modeling of survey responses from 148 manufacturers concerning 592 suppliers. Results indicate that supplier innovativeness has positive impacts on multiple dimensions of manufacturer performance. Results show that when the outsourced activity involves low levels of design responsibility by the supplier, it is more beneficial for the two partners to have contrasting learning styles. However, when the outsourced activity is design‐intensive, it is more beneficial to have a supplier with an explorative learning style.
Are cell salvage and autologous blood transfusion safe in endonasal surgery?
Authors: Anderson Shane , Panizza Ben
Published: February 2010

Objective: Endoscopic transnasal approaches to the skull base and intracranial disease are an emerging subspecialty. The limits of this approach are often dictated by exposure and blood loss. Cell salvage techniques are widely used in other surgical fields. However, in otolaryngology, questions remain regarding its safety because work is performed in a contaminated field. In this literature review, we present the evidence for perioperative cell saver blood transfusion in potentially contaminated fields and the need for further investigation of its use in endonasal surgery.

Data Sources: MEDLINE and Evidence Based Medicine Reviews databases were searched for relevant articles.

Review Methods: All English articles discussing autologous blood transfusion in endonasal surgery were reviewed.

Results: Despite a wide search pattern, no articles that discuss this topic were found in the English literature. Therefore, we went on to present data on the general use of cell saver blood in contaminated fields.

Conclusion: Cell saver blood is widely accepted in surgery. It offers many advantages in elective operations in which blood loss is expected to be significant. Cell saver blood has been transfused from contaminated fields in other forms of surgery without an associated increase in morbidity. There is good evidence that antibiotic prophylaxis is mandatory in this setting. There is no direct evidence that cell salvage blood is safe in endonasal surgery. Cell salvage is part of a multimodality approach, including the use of hypotensive anesthesia, topical procoagulants, a dedicated team with appropriate equipment, and a good surgical technique with a focus on hemostasis.
Local mineral equilibrium in metamorphism: development of D. Korzhinskii’s ideas (on 110th anniversary of D.S. Korzhinskii)
Authors: Reverdatto V.V.
Published: February 2010

In 1950, D. Korzhinskii hypothesized that minerals in metamorphic reactions can be in local equilibrium. Proceeding from this idea, G. Fisher and R. Joesten later developed a realistic model of metamorphism kinetics. The model included diffusive mass transport in intergranular fluid controlled by the concentrations of components and chemical potential gradients, local-equilibrium reactions between minerals and pore fluid, mass balance of components, etc. The Korzhinskii–Fisher–Joesten model can provide clues to the duration of metamorphic events as inferred from mineral chemistry, free energy of phases, and rock textures and structures. The respective modeling of metamorphic reactions, with regard to spatial distribution of mineral grains, has implications for the transport and balance of chemical components. The balance of components (except volatiles) is restricted to domains of hundredth fractions of a cubic millimeter to several cubic meters. This may be the minimum size of an elementary domain in which minerals are in local equilibrium.
Regularities in the impurity element content of minerals during hydrothermal ore formation
Authors: Samusikov V.P.
Published: February 2010

Many goldfields host scores of discovered gold ore occurrences with unclear prospects because of their insufficient geologic exploration. Since exploration is expensive, the occurrences should be first appraised by low-cost methods. Studying the typomorphic features of minerals from the goldfields of the Upper Yana–Kolyma region, we have established a relationship between the contents of isomorphic impurity elements (IIE) and the degree of solution supersaturation (DSS). Preliminary studies show that, based on this relationship, criteria can be developed for revealing “concealed” mineralogical–geochemical zonation and predicting mineralization to depth. The determining factor for the behavior of IIE, depending on the DSS, is their distribution coefficient (K) with respect to the host element. If K > 1, the content of these elements decreases with increasing DSS during ore deposition; if K < 1, it increases. When a solution contains IIE with K > 1 and K < 1, they behave according to their distribution coefficients. In other words, when the DSS increases during ore deposition, IIE with K > 1 will be typical of early mineral segregations, and IIE with K < 1, of late ones. If the crystallization front migrates, this must give rise to a vertical zonation in the content of both groups of elements. The content of elements with K > 1 will decrease upsection, and that of elements with K < 1 will increase (“concealed” mineralogical–geochemical zonation). In connection with this subject, the paper reports data using native gold as an example. The behavior of Ag, Sb, Hg, Cu, Ni, and Co is discussed depending on the depth of deposit formation from the paleosurface (deep-seated → shallow); in the vertical section of individual deposits; depending on mineralization stages; in the cross-section of individual crystals with a zonal structure. The behavior of Ag, Sb, and Hg has been shown to be opposite to that of Cu, Ni, and Co in all these aspects. With respect to Au, the first group of elements has K < 1, and the second one, K > 1. Copper and antimony are of particular interest. In the vertical section of individual deposits, the Cu content of gold increases with depth and the Sb content decreases. The Cu/Sb ratio can be used to estimate the erosional truncation level of deposits and thus predict their extension to depth. Examples of well-explored deposits are given.
Kerogen from the Cambrian deposits of the Kuonamka Formation (northeastern Siberian Platform)
Authors: Parfenova T.M. , Kontorovich A.E. , Borisova L.S. , Melenevskii V.N.
Published: February 2010

Kerogens from the Lower and Middle Cambrian deposits of the Kuonamka Formation in the northeastern Siberian Platform have been analyzed by modern methods. We have determined the pyrolytic characteristics of insoluble organic matter and the contents of C, H, S, N, O, and the stable C isotope. The type and catagenesis of organic matter have been estimated, as well as the generating potential of oil source rocks. It has been found that the composition of kerogens taken from the Molodo River outcrops was affected by supergene processes and that the degree of their alteration is related to the organic content of rocks and their structure.
The regularities in the structural group composition of high-molecular heteroatomic petroleum components
Authors: Golovko A.K. , Gorbunova L.V. , Kam’yanov V.F.
Published: February 2010

We generalized experimental data on the structural group composition and macrostructural characteristics of high-molecular compounds (HMCs)—hydrocarbons, resins, and asphaltenes—from more than 180 crude oil samples extracted from different oil fields of Eurasia. Most of oil resin molecules contain 1–3 structural blocks, each consisting of 0–3 aromatic and 0–5 naphthenic rings in different combinations, with the total number of rings in each block not exceeding 5–6. The average molecular weights of resins are no more than 100–1500 a.m.u. Asphaltenes differ from resins from the same source in the larger number of structural blocks (mainly tri- or tetracyclic aromatic) in molecule (up to five), lower degrees of substitution of aromatic cores, and smaller portions of carbon atoms in saturated fragments. The average molecular weights of asphaltenes measured by naphthalene cryoscopy do not exceed 2500 a.m.u. Owing to intermolecular interactions, HMCs form various associates and polymolecular particles, including quasi-crystalline “batches” and multibatch aggregates. Spontaneous disintegration and formation of such particles make the oils dynamically equilibrium polydisperse systems. We have developed the main regularities of compositional and structural changes of HMCs depending on the depth of occurrence, age, and lithologic composition of oil-bearing deposits. Being chemically labile heteroatomic substances, petroleum HMCs are more rapidly subjected to compositional and structural transformations than hydrocarbons, i.e., are more responsive to changes in strata conditions.
Naphthene-aromatic hydrocarbons in oils of different genesis
Authors: Pevneva G.S. , Voronetskaya N.G. , Golovko Yu.A. , Golovko A.K.
Published: February 2010

Naphthene-benzenes, naphthene-naphthalenes, and naphthene-phenantrenes have been extracted with methanol from mono-, bi-, and triarene fractions of oils of different genetic types from the West Siberian, Timan–Pechora, North Caucasian, and Pannonian (Serbia) oil-and-gas-bearing basins. The hydrocarbon composition and molecular-mass distribution (MMD) of naphthene-arenes have been determined by mass spectrometry. Naphthene-benzene and naphthene-naphthalene molecules contain one to six naphthenic cycles, whereas naphthene-phenantrene molecules contain one to three naphthenic rings. The number of carbon atoms in the alkyl groups of naphthene-benzenes, naphthene-naphthalenes, and naphthene-phenantrenes reaches 38, 20, and 19, respectively. Distinctive features of group compositions and MMD of naphthene-arenes have been revealed in oils generated by different organic matter.
Effect of inclined conductivity anisotropy on frequency induction and TEM data
Authors: Epov M.I. , Antonov E.Yu. , Fedorov A.I.
Published: February 2010

The harmonic electromagnetic field of a vertical magnetic dipole above an anisotropic half-space has been simulated using a forward algorithm for layered conductive media with inclined anisotropy. Inclined anisotropy has been found out to change the typical behavior of frequency and transient responses. Qualitative interpretation of FD loop–loop responses of a conducting earth with inclined anisotropy requires taking into account the receiver azimuth dependence of apparent resistivities. In the case of time-domain measurements, this dependence is absent but the apparent resistivities are higher at late times.
TEM-TDEM soundings with the use of vertical loops
Authors: Mogilatov V.S. , No A.Yu.
Published: February 2010

In the course of scientific collaboration, we were involved in discussion on the capacity of a vertical loop configuration to resolve thin high-resistivity layers, which is quite an interesting and largely debated point. We report a small forward modeling study including an algorithm based on an analytical solution by separation of variables and a respective program for computing the time-domain TEM field of a horizontal magnetic dipole. We infer that the subsurface vertical loop system shows no critical advantage in resolving thin insulating inclusions.
Nucleosomal Context of Binding Sites Influences Transcription Factor Binding Affinity and Gene Regulation
Authors: Dai Zhiming , Dai Xianhua , Xiang Qian , Feng Jihua
Published: February 2010

Transcription factor (TF) binding to its DNA target site plays an essential role in gene regulation. The location, orientation and spacing of transcription factor binding sites (TFBSs) also affect regulatory function of the TF. However, how nucleosomal context of TFBSs influences TF binding and subsequent gene regulation remains to be elucidated. Using genome-wide nucleosome positioning and TF binding data in budding yeast, we found that binding affinities of TFs to DNA tend to decrease with increasing nucleosome occupancy of the associated binding sites. We further demonstrated that nucleosomal context of binding sites is correlated with gene regulation of the corresponding TF. Nucleosome-depleted TFBSs are linked to high gene activity and low expression noise, whereas nucleosome-covered TFBSs are associated with low gene activity and high expression noise. Moreover, nucleosome-covered TFBSs tend to disrupt coexpression of the corresponding TF target genes. We conclude that nucleosomal context of binding sites influences TF binding affinity, subsequently affecting the regulation of TFs on their target genes. This emphasizes the need to include nucleosomal context of TFBSs in modeling gene regulation.
Significant Deviations in the Configurations of Homologous Tandem Repeats in Prokaryotic Genomes
Authors: Hirayama Shintaro , Mizuta Satoshi
Published: February 2010

We explored the possibilities of whole-genome duplication (WGD) in prokaryotic species, where we performed statistical analyses of the configurations of the central angles between homologous tandem repeats (TRs) on the circular chromosomes. At first, we detected TRs on their chromosomes and identified equivalent tandem repeat pairs (ETRPs); here, an ETRP is defined as a pair of tandem repeats sequentially similar to each other. Then we carried out statistical analyses of the central angle distributions of the detected ETRPs on each circular chromosome by way of comparisons between the detected distributions and those generated by null models. In the analyses, we estimated a P value by a simulation using the Kullback–Leibler divergence as a distance measure between two distributions. As a result, the central angle distributions for 8 out of the 203 prokaryotic species showed statistically significant deviations (P<0.05). In particular, we found out the characteristic feature of one round of WGD in Photorhabdus luminescens genome and that of two rounds of WGD in Escherichia coli K12.
In SilicoCharacterization and Homology Modeling of Thylakoid Bound Ascorbate Peroxidase from a Drought Tolerant Wheat Cultivar
Authors: Katiyar A. , Lenka S.K. , Lakshmi K. , Chinnusamy V. , Bansal K.C.
Published: February 2010

Ascorbate peroxidase, a haem protein (EC 1.11.1.11), efficiently scavenges hydrogen peroxide (H2O2) in cytosol and chloroplasts of plants. In this study, a full-length coding sequence of thylakoid-bound ascorbate peroxidase cDNA (TatAPX) was cloned from a drought tolerant wheat cultivar C306. Homology modeling of the TatAPX protein was performed by using the template crystal structure of chloroplastic ascorbate peroxidase from tobacco plant (PDB: 1IYN). The model structure was further refined by molecular mechanics and dynamic methods using various tools such as PROCHECK, ProSA and Verify3D. The predicted model was then tested for docking with H2O2, the substrate for TatAPX enzyme. The results revealed that Arg233 and Glu255 in the predicted active site of the enzyme are two important amino acid residues responsible for strong hydrogen bonding affinity with H2O2, which might play an important role in scavenging of H2O2 from the plant system.