bluuebunny/crossref_metadata_2025 huggingface dataset:
OP91 Are there Gender Differences in Consultation Patterns Prior to Melanoma, CRC and Lung Cancer Diagnosis and Cancer Survival: An Analysis of Routinely Collected General Practice Data?
Authors: Wang Y , Hunt K , Nazareth I , Freemantle N , Peterson I
Published: September 2013

Background

Consultation rates with general practitioners (GPs) are higher in women than in men from late childhood through middle age, though not in childhood and later life. This gender patterning, and qualitative data documenting men’s apparent reluctance to consult, has fuelled widespread assumptions that men are always more reluctant to consult and this may partly explain gender differences in longevity (delayed consultation leading to later diagnosis and decreased opportunities for treatment in men). However, few studies have critically examined this assumption or compared consultation patterns in men and women with similar morbidity. Here we use UK general practice data to examine whether there are gender differences in incidence, survival and consultation patterns prior to diagnosis in patients with three common non-sex-specific cancers: lung, colo-rectal (CRC) and melanoma.

Methods

We used data from the Health Improvement Network (THIN) database to identify cohorts diagnosed between 1997–2006 with lung cancer (LC) (n = 9,872), CRC (n = 7,075) and melanoma (n = 1,429). Sex-specific annual incidence rates, cumulative probability of survival to 5 years and consultation patterns in the 12 months preceding diagnosis were compared.

Results

In 5,041 men and 3,292 women who died within 5 years following a LC diagnosis, average survival time was 7.9 months. There was little difference in survival between men and women (HR 0.946, p=0.046); the small survival advantage was in men. On average people diagnosed with LC had 10 consultations in the year prior to diagnosis (men 10.1 [95% CI 10.05, 12.21], women 11.0 [10.87, 11.07]). There were no gender differences in consultation rates in any month in the year preceding diagnosis. 2,903 men and 2,291 women died within 5 years following a CRC diagnosis. Average survival time in months differed little by gender (17.6 (men) and 15.4 (women)). Consultation patterns were again similar in the year prior to diagnosis (men 8.99 [8.89, 9.09], women 9.43 [9.32, 9,54]), and did not differ by gender in any month in that year. Similar results are presented for melanoma.

Conclusion

If gender differences in propensity to consult (reluctance amongst men, leading to later diagnosis) were to make a substantial impact on gender differences in mortality, we would expect large gender differences in survival and/or in consultation patterns prior to diagnosis in the most common cancers. This analysis provides strong evidence against this explanation for gender differences in health, and suggests the need for a more critical view of gender and consultation.
OP93 Common Epidemiological Errors: Over-Adjustment for Confounders and Mediators in Lifecourse Research
Authors: Gilthorpe M S , Tilling K , Jiang T , Baxter P D
Published: September 2013

Background

Each year numerous studies evaluate longitudinal data within a lifecourse context with later-life health status (e.g. blood pressure) analysed with respect to repeated measures of early-life experiences (e.g. body mass) using standard multiple linear/logistic regression. Although more sophisticated methods are available, some have been shown to be problematic, hence there remains confusion around which is the most appropriate analytical strategy. Standard multiple regression nevertheless suffers text-book errors in this lifecourse context that are sadly perpetuated despite previous warnings. We revisit these problems with a simulation study to give clear guidance on what happens if basic medical statistics dos and don’ts are ignored.

Methods

We simulated a lifecourse dataset comprising repeated measures of z-score body mass at regular intervals following birth using a multivariate normal (9 outcomes) with correlation between birth weight (BW) and adult weight (AW) of 0.1, and adjacent intermediate outcome correlations derived as (0.1)^1/8. We simulated an adult z-score systolic blood pressure (SBP) with correlations between SBP and BW of -0.1, between SBP and AW of 0.2, and correlations between SBP and each intervening body mass measure extrapolated linearly between -0.1 and 0.2. We conducted a series of basic regression analyses, akin to those frequently seen in lifecourse research. Each simulation contained 5000 subjects (assumed to be of one sex) and was repeated 10,000 times to obtain 95% empirical credible intervals.

Results

As previously identified, analyses with BW as the exposure saw point estimates move from the null when mediators were inappropriately included, yielding exaggerated interpretation of the impact of BW, and this was persistent irrespective of which mediators were chosen. Analyses with AW as the exposure saw attenuation of the AW effects varying according to which prior body mass measures were included as confounders: early-life confounders attenuated from the null whilst later-life confounders attenuated towards the null. This indicates some confusion around the extent and correct interpretation of confounding. Whilst large standard errors potentially mask these anomalies, they are manifest more for mediators or confounders more distal to the exposure.

Conclusion

The common practice to analyse a multitude of longitudinal measures within a lifecourse context in a multiple regression model can lead to confused estimates for the main exposure. More careful consideration of the use of multiple regression is required, with distinction between genuine confounders and mediators becoming more widely understood.
Dramatic differences in activity of purines metabolizing ecto-enzymes between mesenchymal stem cells isolated from human umbilical cord blood and umbilical cord tissue
Authors: Roszek Katarzyna , Bomastek Katarzyna , Drożdżal Marian , Komoszyński Michał
Published: September 2013

The high quality human mesenchymal stem cells (MSCs) with remarkable expansion potential in culture are demonstrated to possess multifold clinical applications. However, their isolation and characterization are difficult and sometimes ambiguous. We exploited nucleotide metabolizing ecto-enzymes for more complete characterization of MSCs. Using standard methods of cell culturing and analyses, we detected significant differences in the activity of ecto-nucleotidases on the surface of MSCs isolated from umbilical cord tissue and MSC-like cells derived from umbilical cord blood. Interestingly, the proliferation rate and the immunophenotypic characteristics of mesenchymal stem cells also correspond to the activities of these enzymes. Compared with the CD90-, CD105-, and CD73-deficient and slowly proliferating UCB-MSC-like cells that had relatively higher ecto-NTPDases activity, the CD90-, CD105-, and CD73-positive and rapidly proliferating UC-MSCs rather had ecto-5′-nucleotidase activity and presented neither ecto-nucleotidases nor adenylate kinase activities. In summary, our results demonstrate for the first time that activity of purine nucleotide metabolizing ecto-enzymes differs significantly between mesenchymal stem cells drawn from different neonatal sources, corresponding with a distinct proliferative potential.
Stress measurement in partially saturated soils and its application to physical modeling of tunnel excavation
Authors: Berthoz Nicolas , Branque Denis , Wong Henry , Subrin Didier
Published: September 2013

The capacity of a commercially available miniature pressure sensor for measuring stress evolutions in a partially saturated soil under quasi-static loads is studied, in view of its later application in laboratory-scale physical models. An extensive calibration program is first performed on a triaxial cell under isotropic loadings. These calibration tests provide useful data for assessing the uncertainty in stress measurements, especially in the case of partially saturated granular materials. Notably, influences of soil density, water content, and average grain size on stress measurements are quantified. Following these tests, an example of stress measurements on an original reduced-scale model of “earth pressure balance shield” (EPBS) is presented, which involves three-dimensional arching effects developing around the shield during excavation.
Cryptic population structure in the severely depleted cowcod,Sebastes levis
Authors: Hess Jon E. , Chittaro Paul , Elz Anna , Gilbert-Horvath Elizabeth A. , Simon Victor , Garza John Carlos
Published: September 2013

Cowcod (Sebastes levis) is a member of a northeastern Pacific Ocean species flock that experienced extensive fishery exploitation. Factors that could produce structure in cowcod include a major biogeographic boundary within cowcod’s geographical distribution; severe declines in abundance, potentially, resulting in reductions in effective population size and divergence owing to genetic drift; and dependence on patchily distributed habitat. We examine the following two questions: (i) is there subdivision present and, if so, is it concordant with the two marine biogeographic regions separated by Point Conception, and (ii) have cowcod experienced loss of genetic variation owing to population size reduction? Coarse-scale genetic and otolith analyses indicated regional structure across Point Conception. However, analysis of 24 microsatellite DNA loci revealed as many as three cryptic, divergent lineages (FCT= 0.194) that meet south of Point Conception. The two southern lineages had higher growth rate than the northerly distributed lineage. In general, cowcod is the least genetically diverse of ∼10 rockfishes surveyed with the same markers, but the recent substantial declines in abundance were not reflected by recent genetic bottleneck analyses.
Analytical formula for electron-impact ionization cross section in the one Coulomb wave model
Authors: Sahlaoui Mohammed , Lasri Boumediene , Bouamoud Mammar
Published: September 2013

In the framework of the one Coulomb wave model, an analytical formula is derived for the triple differential cross section for the ionization of atomic target by electron impact. Both the direct and exchange terms of the transition amplitude are considered. The exchange term is calculated in the present work. However, the direct term is deduced from our previous work (Sahlaoui and Bouamoud. Can. J. Phys. 88, 905 (2010)). The obtained results can be used to compute the transition amplitude defined in others models, as for example, the distorted wave Born approximation and the Coulomb two-wave model. The mathematical techniques developed here can be also used to compute other complicated integrals that can be encountered in atomic physics and quantum chemistry.
AN ALTERNATIVE APPROACH TO MULTI-GAP SUPERCONDUCTIVITY
Authors: MALIK G. P. , DE LLANO M.
Published: September 2013

We draw attention to a feature suggested by a widely-cited paper by Suhl, Matthias, and Walker in the context of multi-gap superconductivity that seems to have escaped serious attention: interaction parameters in a superconductor characterized by two zero-temperature gaps but a single critical temperature must be temperature-dependent. Guided by this cue, we have presented a plausible scenario for a quantitative explanation of the superconducting properties of MgB 2 via an alternative approach — the approach provided by the recently derived set of generalized-BCS equations. Attention is drawn to earlier work in diverse fields where a similar T-dependent approach has been fruitful.
A NONLINEAR VISCOELASTIC-PLASTIC RHEOLOGICAL MODEL FOR ROCKS BASED ON FRACTIONAL DERIVATIVE THEORY
Authors: CHEN HONGJIE , XU WEIYA , WANG WEI , WANG RUBIN , SHI CHONG
Published: September 2013

The soft-matter element between the ideal solid and the ideal liquid is established and is described based on the definition of the fractional derivatives. By replacing a component in the generalized Kelvin model with the soft-matter component and connecting it in series with a nonlinear visco-plastic body, a nonlinear viscoelasto-plastic rheological model is proposed based on the fractional derivatives in order to describe the rheological behaviors of rocks. The data obtained from the triaxial creep tests of a typical rock are simulated with this model and the fitting result is good. The model can describe well three rheological stages of the rock during the triaxial creep tests. The validity of this model is then discussed. In this model, the fractional order β controls creep strain rate in the stable creep stage under the condition of low stress; while the creep index n controls creep rate of the accelerated rheological stage under the condition of high stress. Few parameters and good simulation results manifest the outstanding performance of the model. The model also adopts the damage theory to describe the progressive deterioration of rock viscous coefficient of the accelerated creep stage. The model can also give an excellent description of the three rheological stages of rocks, especially the accelerated creep stage.
NON-HERMITIAN QUANTUM DYNAMICS OF A TWO-LEVEL SYSTEM AND MODELS OF DISSIPATIVE ENVIRONMENTS
Authors: SERGI ALESSANDRO , ZLOSHCHASTIEV KONSTANTIN G.
Published: September 2013

We consider a non-Hermitian Hamiltonian in order to effectively describe a two-level system (TLS) coupled to a generic dissipative environment. The total Hamiltonian of the model is obtained by adding a general anti-Hermitian part, depending on four parameters, to the Hermitian Hamiltonian of a tunneling TLS. The time evolution is formulated and derived in terms of the normalized density operator of the model, different types of decays are revealed and analyzed. In particular, the population difference and coherence are defined and calculated analytically. We have been able to mimic various physical situations with different properties, such as dephasing, vanishing population difference and purification.
THE SPIN–ORBIT INTERACTION AND THE SPIN–SPIN INTERACTION OF PHOTONS IN AN INHOMOGENEOUS MEDIUM
Authors: LI HEHE , BU ZHIGANG , LUO YUEE , CHEN WENBO , JI PEIYONG
Published: September 2013

By means of the optical metric, we investigate the propagation of a polarized light in an inhomogeneous medium in this paper. We find that the evolution of photons is affected by the spin–spin interaction of photons, besides the spin–orbit interaction. Due to the spin–spin interaction, there is a small deflection of the ray trajectory of the polarized light along the direction of the inhomogeneity gradient of the medium. It is different from the transverse deflection described by the spin Hall effect of photons.
KOLMOGOROV COMPLEXITY SPECTRUM FOR USE IN ANALYSIS OF UV-B RADIATION TIME SERIES
Authors: MIHAILOVIĆ DRAGUTIN T. , MALINOVIĆ-MILIĆEVIĆ SLAVICA , ARSENIĆ ILIJA , DREŠKOVIĆ NUSRET , BUKOSA BEATA
Published: September 2013

In this paper, we have used the Kolmogorov complexity and sample entropy measures to estimate the complexity of the UV-B radiation time series in the Vojvodina region (Serbia) for the period 1990–2007. We have defined the Kolmogorov complexity spectrum and have introduced the Kolmogorov complexity spectrum highest value (KCH). We have established the UV-B radiation time series on the basis of their daily sum (dose) for seven representative places in this region using: (i) measured data, (ii) data calculated via a derived empirical formula and (iii) data obtained by a parametric UV radiation model. We have calculated the Kolmogorov complexity (KC) based on the Lempel–Ziv algorithm (LZA), KCH and sample entropy (SE) values for each time series. We have divided the period 1990–2007 into two subintervals: (i) 1990–1998 and (ii) 1999–2007 and calculated the KC, KCH and SE values for the various time series in these subintervals. It is found that during the period 1999–2007, there is a decrease in the KC, KCH and SE, compared to the period 1990–1998. This complexity loss may be attributed to (i) the increased human intervention in the post civil war period causing increase of the air pollution and (ii) the increased cloudiness due to climate changes.
EARLY DETECTION AND LOCALIZATION OF GRAVITATIONAL WAVES FROM COMPACT BINARY COALESCENCES
Authors: WEN LINQING , CHU QI
Published: September 2013

With the first detection of gravitational waves expected in the next decade, increasing efforts are made toward the electromagnetic follow-up observations of gravitational wave events. In this paper, I discuss the prospect of real-time detection and source localization for gravitational waves from neutron star–neutron star binary or neutron star–black hole binary coalescences before their merger. I show that several low-latency search pipelines are already under intensive development with the aim to provide real-time detections of these events. There will also be fast responding and/or wide-field electromagnetic telescopes available to help catch the electromagnetic or particle flashes possibly occurring during or immediately after their merger. It has been shown that a few coalescence events per year can be detected by advanced LIGO-VIRGO detector network tens of seconds before their merger. However, most of these events will have poor sky direction localization for the existing gravitational-wave detector network, making it extremely challenging for follow up observations by astronomical telescopes aiming at catching events around the merger time. A larger detector network including the planned detectors in Japan and in India will play an important role in improving the angular resolution and making prompt follow up observations much more realistic. A new detector at the Southern Hemisphere AIGO will further contribute significantly to this aspect.
MODELING PULSAR TIME NOISE WITH LONG TERM POWER LAW DECAY MODULATED BY SHORT TERM OSCILLATIONS OF THE MAGNETIC FIELDS OF NEUTRON STARS
Authors: ZHANG SHUANG-NAN , XIE YI
Published: September 2013

We model the evolution of the magnetic fields of neutron stars as consisting of a long term power-law decay modulated by short term small amplitude oscillations. Our model predictions on the timing noise [Formula: see text] of neutron stars agree well with the observed statistical properties and correlations of normal radio pulsars. Fitting the model predictions to the observed data, we found that their initial parameter implies their initial surface magnetic dipole magnetic field strength B0 ~ 5 × 1014 G when t0 = 0.4 yr and that the oscillations have amplitude K ~ 10-8 to 10-5 and period T on the order of years. For individual pulsars our model can effectively reduce their timing residuals, thus offering the potential of more sensitive detections of gravitational waves with pulsar timing arrays. Finally our model can also re-produce their observed correlation and oscillations of [Formula: see text], as well as the "slow glitch" phenomenon.
GENERALIZED VARIATIONAL PROCEDURE: AN APPLICATION TO NONPERTURBATIVE QCD
Authors: CIVITARESE O. , HESS P. O. , AMOR-QUIROZ D. A.
Published: September 2013

We present a generalized variational procedure oriented to the algebraic solution of many-body Hamiltonians expressed in bosonic and fermionic variables. The method specializes in the nonperturbative regime of the solutions. As an example, we focus on the application of the method to nonperturbative QCD.
A software-only scheme for managing heap data on limited local memory(LLM) multicore processors
Authors: Bai Ke , Shrivastava Aviral
Published: September 2013

This article presents a scheme for managing heap data in the local memory present in each core of a limited local memory (LLM) multicore architecture. Although managing heap data semi-automatically with software cache is feasible, it may require modifications of other thread codes. Crossthread modifications are very difficult to code and debug, and will become more complex and challenging as we increase the number of cores. In this article, we propose an intuitive programming interface, which is an automatic and scalable scheme for heap data management. Besides, for embedded applications, where the maximum heap size can be profiled, we propose several optimizations on our heap management to significantly decrease the library overheads. Our experiments on several benchmarks from MiBench executing on the Sony Playstation 3 show that our scheme is natural to use, and if we know the maximum size of heap data, our optimizations can improve application performance by an average of 14%.
Contextual partitioning for speech recognition
Authors: Kent Christopher G. , Paul Joann M.
Published: September 2013

Many multicore computers are single-user devices, creating the potential to partition by situational usage contexts, similar to how the human brain is organized. Contextual partitioning (CP) permits multiple simplified versions of the same task to exist in parallel, with selection tied to the context in use. We introduce CP for speech recognition, specifically targeted at user interfaces in handheld embedded devices. Contexts are drawn from webpage interactions. CP results in 61% fewer decoding errors, 97% less training for vocabulary changes, near-linear scaling potential with increasing core counts, and up to a potential 90% reduction in power usage.
Effect of Ar/CH4Mixture Ratio on Properties of Ag/C:H Nanocomposite Prepared by DC Sputtering
Authors: Mohsen Soltani E. , Ghorannevis Z. , Shirazi M.
Published: September 2013

Ag/C:H films were deposited by DC sputtering method on Si substrates with different Ar/CH4gas mixture ratios. Effect of Ar/CH4gas mixture ratios was investigated on optical and structural properties of Ag/C:H films by FTIR spectroscopy analysis, X-Ray diffractometry (XRD), scanning electron microscopy (SEM), and atomic force microscopy (AFM), respectively. In order to evaluate the effect of gas flow ratio on the optical and structural properties of Ag/C:H films, Ar/CH4gas ratio was changed by keeping the Ar flow rate constant while varying the CH4gas flow rate (2, 5, and 10 SCCM). From FTIR analysis it was observed that increase in the Ar/CH4gas ratio results in decreasing the sputtered Ag nanoparticles and increasing of C–H bonds. Also from XRD pattern it was found that intensity of Ag crystalline plane and average grain size decrease by adding CH4to working gas admixture. From SEM and AFM micrographs, size of the grains also became smaller on the surface of the films, which will lead to decreasing the roughness of the deposited thin films.
Acute MRSA Sinusitis with Intracranial Extension and Marginal Vancomycin Susceptibility
Authors: Kumar Parvathi S. , Cunnion Kenji M.
Published: September 2013

Methicillin resistantStaphylococcus aureus(MRSA) is increasingly being described as a cause of acute sinusitis. We present a patient with acute MRSA sinusitis complicated by rapid intracranial extension, marginal vancomycin susceptibility (MIC = 2 mg/L), delayed drainage of intracranial abscess, and subsequent development of rifampin resistance. Given the relatively high risk of intracranial extension of severe acute bacterial sinusitis and high mortality associated with invasive MRSA infections, we suggest early surgical drainage of intracranial abscesses in these circumstances. We believe this is important given the limited intracranial penetration of currently available treatment options for MRSA, especially those with a vancomycin minimal inhibitory concentration (MIC) of ≥2 mg/L.
Outpatients’ Perspectives on Problems and Needs Related to Female Genital Mutilation/Cutting: A Qualitative Study from Somaliland
Authors: Fried Sarah , Mahmoud Warsame Amina , Berggren Vanja , Isman Elisabeth , Johansson Annika
Published: September 2013

Aim. To explore female outpatients’ perspectives on problems related to female genital mutilation/cutting (FGM/C) and their views on information, care, and counseling.Setting. An FGM/C support center at a maternity clinic in Hargeisa, Somaliland.Methods. A qualitative, descriptive study, using content analysis of seven semistructured interviews with female outpatients.Results. All participants had been ignorant of the etiology of their FGM/C-related complications and hesitant to seek care. All had undergone infibulation but did not wish the same for their daughters. In recent years they had learnt through religious leaders and media campaigns that infibulation was unapproved by Islam. A less severe FGM/C type, “Sunna,” was more accepted; however, few could define what “Sunna” meant. Condemning and ridiculing attitudes against uncircumcised women prevailed in their community.Conclusions. New ideas and concepts related to FGM/C enter the common discourse in the Somali society while traditional norms and values still prevail. Religion was shown to have a strong impact on FGM/C practices and beliefs. Interventions aiming to raise awareness of health consequences of all types of FGM/C, as well as where to seek care for complications, are needed in Somaliland. Involvement of religious leaders in anti-FGM/C programs is essential.
Low-Dose Amphotericin B and Murine Dialyzable Spleen Extracts Protect against SystemicCandidaInfection in Mice
Authors: Robledo-Ávila F. , Pérez-Tapia M. , Limón-Flores A. , Pavon L. , Hernández-Pando R. , Wong-Baeza I. , González-González G. , Tovar C. , Estrada-Parra S. , Estrada-García I.
Published: September 2013

Candida albicanscauses opportunistic systemic infections with high mortality (30%–50%). Despite significant nephrotoxicity, amphotericin (AmB) is still used for the treatment of this serious fungal infection. Therefore, alternative treatments are urgently needed. Dialyzable leukocyte extracts have been used successfully to treat patients with mucocutaneous candidiasis, but their effectiveness in systemic candidiasis has not been evaluated. In this study, low-dose AmB (0.1 mg/kg) plus 10 pg of murine dialyzable spleen extracts (mDSE) were tested in a systemic candidiasis mouse model. Survival, tissue fungal burden, kidney damage, kidney cytokines, and serum levels of IL-6 and hepcidin were evaluated. Our results showed that the combined treatment of low-dose AmB plus mDSE improved survival and reduced kidney fungal burden and histopathology; these effects correlated with increased kidney concentration of IFN-γand TGF-β1, decreased levels of TNF-α, IL-6, and IL-10, as well as high levels of systemic IL-6 and hepcidin. Low-dose AmB and mDSE synergized to clear the infectious agent and reduced tissue damage, confirming the efficacy of a low dose of AmB, which might decrease the risk of drug toxicity. Further studies are necessary to explore these findings and its implications in future therapeutic approaches.
Energy Dissipation and the High‐Strain Rate Dynamic Response of Vertically Aligned Carbon Nanotube Ensembles Grown on Silicon Wafer Substrate
Authors: Mantena P. Raju , Tadepalli Tezeswi , Pramanik Brahmananda , Boddu Veera M. , Brenner Matthew W. , Stephenson L. David , Kumar Ashok
Published: September 2013

The dynamic mechanical behavior and high‐strain rate response characteristics of a functionally graded material (FGM) system consisting of vertically aligned carbon nanotube ensembles grown on silicon wafer substrate (VACNT‐Si) are presented. Flexural rigidity (storage modulus) and loss factor (damping) were measured with a dynamic mechanical analyzer in an oscillatory three‐point bending mode. It was found that the functionally graded VACNT‐Si exhibited significantly higher damping without sacrificing flexural rigidity. A Split‐Hopkinson pressure bar (SHPB) was used for determining the system response under high‐strain rate compressive loading. Combination of a soft and flexible VACNT forest layer over the hard silicon substrate presented novel challenges for SHPB testing. It was observed that VACNT‐Si specimens showed a large increase in the specific energy absorption over a pure Si wafer.
Silver Nanoparticles and Mitochondrial Interaction
Authors: Bressan Eriberto , Ferroni Letizia , Gardin Chiara , Rigo Chiara , Stocchero Michele , Vindigni Vincenzo , Cairns Warren , Zavan Barbara
Published: September 2013

Nanotechnology has gone through a period of rapid growth, thus leading to the constant increase in the application of engineered nanomaterials in daily life. Several different types of nanoparticles have been engineered to be employed in a wide array of applications due to their high surface to volume ratio that leads to unique physical and chemical properties. So far, silver nanoparticles (AgNps) have been used in many more different medical devices than any other nanomaterial, mainly due to their antimicrobial properties. Despite the promising advantages posed by using AgNps in medical applications, the possible health effects associated with the inevitable human exposure to AgNps have raised concerns as to their use since a clear understanding of their specific interaction with biological systems has not been attained yet. In light of such consideration, aim of the present work is the morphological analysis of the intracellular behavior of AgNps with a diameter of 10 nm, with a special attention to their interaction with mitochondria.
Evaluation of Chronic Liver Disease: Does Ultrasound Scoring Criteria Help?
Authors: Afzal Shaista , Masroor Imrana , Beg Madiha
Published: September 2013

Noninvasive approaches for assessment of liver histology include routine laboratory tests and radiological evaluation. The purpose of our study was to determine the utility of a simplified scoring system based on routinely evaluated ultrasound features for the evaluation of chronic liver disease and correlate it with the histological findings. For this cross-sectional analytical study the data was collected prospectively by nonprobability purposive sampling technique. The ultrasound variables/parameters and their assigned scoring system that was a modified version adopted from published literature were evaluated. Sensitivity, specificity, positive and negative predictive values of the liver morphological score and combined score of liver morphology and sizes was determined using stage and grade as reference standard. Our results show a high sensitivity and PPV of liver morphological sonographic evaluation for the staging and grading of CLD respectively thus supporting it as a screening diagnostic strategy. Of the three liver morphology variables, specificity of liver surface evaluation was highest for the stage of fibrosis and grade of inflammation. The simplified ultrasound scoring system evaluated in our study is clinically relevant and reproducible for differentiating patients with CLD with mild or no fibrosis from moderate to severe fibrosis.
Graphene Oxide Reinforced Polylactic Acid/Polyurethane Antibacterial Composites
Authors: An Xiaoli , Ma Haibin , Liu Bin , Wang Jizeng
Published: September 2013

Nanocomposites from PLA/PU containing small concentrations of graphene oxide (GO) were prepared by simple liquid‐phase mixing followed by casting. The as‐prepared ternary PLA/PU/GO composite films exhibited good antibacterial activity against the gram‐positive Staphylococcus aureus and the gram‐negative Escherichia coli, due to the excellent antibacterial property of GO sheets with high specific surface area. The addition of GO inhibited the attachment and proliferation of microbes on the film surfaces, resulting in that the PLA/PU/GO composite films show remarkably improved antibacterial activity compared with PLA/PU composite film. The inhibition efficiency is proportional to the amount of GO. Furthermore, PLA/PU/GO composite fibrous paper was fabricated using electrospinning and exhibited good biocompatibility. The addition of GO does not destroy normal cell’s proliferation and differentiation. PLA/PU/GO composites with good antibacterial activity and biocompatibility make it attractive for the environmental and clinical applications and also provide a candidate for future application of tissue engineering.
Traumatic Mitral Valve and Pericardial Injury
Authors: Shaikh Nissar , Ummunissa Firdous , Abdel Sattar Mohamed
Published: September 2013

Cardiac injury after blunt trauma is common but underreported. Common cardiac trauma after the blunt chest injury (BCI) is cardiac contusion; it is very rare to have cardiac valve injury. The mitral valve injury during chest trauma occurs when extreme pressure is applied at early systole during the isovolumic contraction between the closure of the mitral valve and the opening of the aortic valve. Traumatic mitral valve injury can involve valve leaflet, chordae tendineae, or papillary muscles. For the diagnosis of mitral valve injury, a high index of suspicion is required, as in polytrauma patients, other obvious severe injuries will divert the attention of the treating physician. Clinical picture of patients with mitral valve injury may vary from none to cardiogenic shock. The echocardiogram is the main diagnostic modality of mitral valve injuries. Patient’s clinical condition will dictate the timing and type of surgery or medical therapy. We report a case of mitral valve and pericardial injury in a polytrauma patient, successfully treated in our intensive care unit.
A Solution-Based Approach for Mo-99 Production: Considerations for Nitrate versus Sulfate Media
Authors: Youker Amanda J. , Chemerisov Sergey D. , Kalensky Michael , Tkac Peter , Bowers Delbert L. , Vandegrift George F.
Published: September 2013

Molybdenum-99 is the parent of Technetium-99m, which is used in nearly 80% of all nuclear medicine procedures. The medical community has been plagued by Mo-99 shortages due to aging reactors, such as the NRU (National Research Universal) reactor in Canada. There are currently no US producers of Mo-99, and NRU is scheduled for shutdown in 2016, which means that another Mo-99 shortage is imminent unless a potential domestic Mo-99 producer fills the void. Argonne National Laboratory is assisting two potential domestic suppliers of Mo-99 by examining the effects of a uranyl nitrate versus a uranyl sulfate target solution configuration on Mo-99 production. Uranyl nitrate solutions are easier to prepare and do not generate detectable amounts of peroxide upon irradiation, but a high radiation field can lead to a large increase in pH, which can lead to the precipitation of fission products and uranyl hydroxides. Uranyl sulfate solutions are more difficult to prepare, and enough peroxide is generated during irradiation to cause precipitation of uranyl peroxide, but this can be prevented by adding a catalyst to the solution. A titania sorbent can be used to recover Mo-99 from a highly concentrated uranyl nitrate or uranyl sulfate solution; however, different approaches must be taken to prevent precipitation during Mo-99 production.
Acute Acalculous Cholecystitis due to Viral Hepatitis A
Authors: Kaya Safak , Eskazan Ahmet Emre , Ay Nurettin , Baysal Birol , Bahadir Mehmet Veysi , Onur Arzu , Duymus Recai
Published: September 2013

Inflammation of the gallbladder without evidence of calculi is known as acute acalculous cholecystitis (AAC). AAC is frequently associated with gangrene, perforation, and empyema. Due to these associated complications, AAC can be associated with high morbidity and mortality. Medical or surgical treatments can be chosen according to the general condition of the patient, underlying disease and agent. Particularly in acute acalculous cholecystitis cases, early diagnosis and early medical treatment have a positive effect on the patient and protect them from surgical trauma. ACC is a rare complication of acute viral hepatitis A. Herein, we present an adult patient of acalculous cholecystitis due to acute viral hepatitis A. She responded to the conservative management.
Chemical Modification of Polysaccharides
Authors: Cumpstey Ian
Published: September 2013

This review covers methods for modifying the structures of polysaccharides. The introduction of hydrophobic, acidic, basic, or other functionality into polysaccharide structures can alter the properties of materials based on these substances. The development of chemical methods to achieve this aim is an ongoing area of research that is expected to become more important as the emphasis on using renewable starting materials and sustainable processes increases in the future. The methods covered in this review include ester and ether formation using saccharide oxygen nucleophiles, including enzymatic reactions and aspects of regioselectivity; the introduction of heteroatomic nucleophiles into polysaccharide chains; the oxidation of polysaccharides, including oxidative glycol cleavage, chemical oxidation of primary alcohols to carboxylic acids, and enzymatic oxidation of primary alcohols to aldehydes; reactions of uronic-acid-based polysaccharides; nucleophilic reactions of the amines of chitosan; and the formation of unsaturated polysaccharide derivatives.
Numerical Analysis of Copper-Indium-Gallium-Diselenide-Based Solar Cells by SCAPS-1D
Authors: Ouédraogo S. , Zougmoré F. , Ndjaka J. M.
Published: September 2013

We used a one-dimensional simulation program Solar Cell Capacitance Simulator in 1 Dimension (SCAPS-1D) to investigate Copper-Indium-Gallium-Diselenide- (CIGS-) based solar cells properties. Starting with a conventional ZnO-B/i-ZnO/CdS/CIGS structure, we simulated the parameters of current-voltage characteristics and showed how the absorber layer thickness, hole density, and band gap influence the short-circuit current density (Jsc), open-circuit voltage (Voc), fill factor (FF), and efficiency of solar cell. Our simulation results showed that all electrical parameters are greatly affected by the absorber thickness (w) below 1000 nm, due to the increase of back-contact recombination and very poor absorption. Increasing hole density (p) or absorber band gap (Eg) improvesVocand leads to high efficiency, which equals value of 16.1% whenp= 1016 cm−3andEg=1.2 eV. In order to reduce back-contact recombination, the effect of a very thin layer with high band gap inserted near the back contact and acting as electrons reflector, the so-called back-electron reflector (EBR), has been investigated. The performances of the solar cells are significantly improved, when ultrathin absorbers (w< 500 nm) are used; the corresponding gain ofJscdue to the EBR is 3 mA/cm2. Our results are in good agreement with those reported in the literature from experiments.
Upconversion Luminescence and Photodegradation Performances of Pr Doped Y2SiO5 Nanomaterials
Authors: Yang Yi , Liu Cheng , Mao Ping , Wang Lian-Jun
Published: September 2013

Yttrium silicates Y2SiO5 upconversion nanomaterials with different doping concentrations of praseodymium ion Pr are prepared by using a sol‐gel method. X‐ray diffractometer, SEM, Fourier transform infrared spectrometer, and fluorescence spectrometer have been employed to test the crystal structure and upconversion luminescence performances. The results indicate that samples calcined higher than 950°C present fine crystal structures, of which Si‐O‐Si band at 757–1048 cm−1 splits into three fine peaks. The crystal size of the samples calcined at 950°C and 1000°C is 29.1 nm and 66.7 nm, respectively. The luminescence intensities of the samples are increasing at first and then decreasing, with the increasing of the doping concentrations of 0.47%, 0.77%, 0.96%, 2.95%, and 4.93%. Nanomaterial sample doped 0.96% Pr emits the highest upconversion luminescence intensity of 6.43 × 106 cps and shows the best photodegradation performance for nitrobenzene wastewater. It demonstrates that too much of Pr doping concentration would result in quenching of the fluorescence. Nevertheless, as the degradation time expands, sample doped 0.96% Pr shows much faster increasing of photodegradation rate than samples of other doping concentrations and reaches to a high photodegradation rate of 97.14% in 6 hours for 10 mg/L nitrobenzene wastewater.
Role of Toll-Like Receptor 4 on Lupus Lung Injury and Atherosclerosis in LPS-Challenge ApoE−/−Mice
Authors: Ni Jing-qin , Ouyang Qiufang , Lin Ling , Huang Ziyang , Lu Huixia , Chen Xiaoqing , Lin Huili , Wang Zhenhua , Xu Dongming , Zhang Yun
Published: September 2013

To investigate the pathologic mechanisms of toll-like receptor 4 (TLR4) in lung injury and atherosclerosis, ApoE−/−or wild-type mice were intraperitoneally administered saline, lipopolysaccharides (LPS), or LPS plus TAK-242 (TLR4 inhibitor), respectively, twice a week for 4 weeks. Serum autoantibody of antinuclear antibody (ANA), anti-double-stranded DNA (anti-dsDNA), and cytokines of interferon-gamma (IFN-γ), tumor necrosis factor (TNF-α), and interleukin-1 (IL-1β) were assessed by ELISA. Hematoxylin and eosin (HE) and Perl's stains for lung pathomorphology as well as HE staining for atherosclerosis were employed. TLR4 in macrophages was detected by double immunofluorescent staining. While protein expressions of TLR4, nuclear factor-kappa B p65 (NF-κB p65), and B cell activating factor belonging to the TNF family (BAFF) were examined by immunohistochemistry. We found that serum autoantibody (ANA and anti-dsDNA), cytokines (IFN-γ, TNF-α, IL-1β), lung inflammation, and intima-media thickness in brachiocephalic artery were obviously increased after LPS challenge in both genotypes, but to a lesser extent in wild-type strains. And those alterations were alleviated by coadministration of LPS and TAK-242. Mechanistically, upregulation of TLR4, NF-κb, and BAFF was involved. We concluded that TLR4/NF-κb/BAFF in macrophages might be a possible common autoimmune pathway that caused lung injury and atherosclerosis. TLR4 signal will be a therapeutic target in atherosclerosis and immune-mediated lung injury.
Improvement of Daptomycin Production inStreptomyces roseosporusthrough the Acquisition of Pleuromutilin Resistance
Authors: Li Linli , Ma Tingmei , Liu Qing , Huang Yuqi , Hu Changhua , Liao Guojian
Published: September 2013

Daptomycin, a cyclic lipopeptide antibiotic produced byStreptomyces roseosporus, displays potent activity against a variety of gram-positive pathogens. There is a demand for generating high-producing strains for industrial production of this valuable antibiotic. Ribosome engineering is a powerful strategy to enhance the yield of secondary metabolites. In this study, the effect of a diterpenoid antibiotic pleuromutilin resistance mutation on daptomycin production was assessed. Spontaneous pleuromutilin-resistant derivatives ofS. roseosporuswere isolated. Sequencing ofrplClocus (encoding the ribosomal protein L3) showed a point mutation at nt 455, resulting in the substitution of glycine with valine. G152V mutants showed increased production of daptomycin by approximately 30% in comparison with the wild-type strain. Its effect on daptomycin production was due to enhanced gene transcription of the daptomycin biosynthetic genes. In conclusion, pleuromutilin could be used as a novel ribosome engineering agent to improve the production of desired secondary metabolites.
Stability Switches of Arbitrary High‐Order Consensus in Multiagent Networks with Time Delays
Authors: Yang Bo
Published: September 2013

High‐order consensus seeking, in which individual high‐order dynamic agents share a consistent view of the objectives and the world in a distributed manner, finds its potential broad applications in the field of cooperative control. This paper presents stability switches analysis of arbitrary high‐order consensus in multiagent networks with time delays. By employing a frequency domain method, we explicitly derive analytical equations that clarify a rigorous connection between the stability of general high‐order consensus and the system parameters such as the network topology, communication time‐delays, and feedback gains. Particularly, our results provide a general and a fairly precise notion of how increasing communication time‐delay causes the stability switches of consensus. Furthermore, under communication constraints, the stability and robustness problems of consensus algorithms up to third order are discussed in details to illustrate our central results. Numerical examples and simulation results for fourth‐order consensus are provided to demonstrate the effectiveness of our theoretical results.
Role of GnRH Neurons and Their Neuronal Afferents as Key Integrators between Food Intake Regulatory Signals and the Control of Reproduction
Authors: Roa Juan
Published: September 2013

Reproductive function is regulated by a plethora of signals that integrate physiological and environmental information. Among others, metabolic factors are key components of this circuit since they inform about the propitious timing for reproduction depending on energy availability. This information is processed mainly at the hypothalamus that, in turn, modulates gonadotropin release from the pituitary and, thereby, gonadal activity. Metabolic hormones, such as leptin, insulin, and ghrelin, act as indicators of the energy status and convey this information to the reproductive axis regulating its activity. In this review, we will analyse the central mechanisms involved in the integration of this metabolic information and their contribution to the control of the reproductive function. Particular attention will be paid to summarize the participation of GnRH, Kiss1, NPY, and POMC neurons in this process and their possible interactions to contribute to the metabolic control of reproduction.
The Bases of and the Number of Representation of Integers
Authors: Kendirli Barış
Published: September 2013

Following a fundamental theorem of Hecke, some bases of and are determined, and explicit formulas are obtained for the number of representations of positive integers by all possible direct sums (111 different combinations) of seven quadratic forms from the class group of equivalence classes of quadratic forms with discriminant −71 whose representatives are .
Dynamics of B-Cell Populations in CSF and Blood in Patients Treated with a Combination of Rituximab and Mitoxantrone
Authors: Evdoshenko Evgeniy , Maslyanskiy Alexey , Lapin Sergey , Zaslavsky Leonid , Dobson Ruth , Totolian Areg , Skoromets Alexander , Bar-Or Amit
Published: September 2013

Background. Mitoxantrone (MTX) and Rituximab (RTX) are successfully used for treatment of multiple sclerosis (MS) and can be combined to increase efficacy. Objective. We used MTX, RTX, and methylprednisolone in a single combined regiment and observed patients prospectively. Methods. We present results of observational pilot study of combined therapy of RTX and MTX in 28 patients with active MS. Therapeutic protocol consisted of two infusions within 14 days. First infusion was 1000 mg methylprednisolone (MP) IV, 1000 mg RTX IV, and 20 mg MTX IV. On day 14, 1000 mg MP IV and 1000 mg RTX IV were given. Patients were followed prospectively from 12 to 48 months. Results and Conclusion. There were no relapses among all 28 patients during the observation period. B-cell depletion of CD19+ and CD19+/CD27+ memory B-cell subpopulation in both compartments was confirmed in all patients at 6 months. We found a more rapid reconstitution of B cells in the CSF than in the peripheral blood and longstanding depression of CD19+CD27+ memory B-cell. Conclusion. Effectiveness of combined regimen of RTX and MTX could be related to longstanding depletion of CD19+CD27+ memory B-cell subset.
Flowshop Scheduling Problems with a Position-Dependent Exponential Learning Effect
Authors: Cheng Mingbao
Published: September 2013

We consider a permutation flowshop scheduling problem with a position-dependent exponential learning effect. The objective is to minimize the performance criteria of makespan and the total flow time. For the two-machine flow shop scheduling case, we show that Johnson’s rule is not an optimal algorithm for minimizing the makespan given the exponential learning effect. Furthermore, by using the shortest total processing times first (STPT) rule, we construct the worst-case performance ratios for both criteria. Finally, a polynomial-time algorithm is proposed for special cases of the studied problem.