bluuebunny/crossref_metadata_2025 huggingface dataset:
Elaboration of Alumina-Zirconia Composites: Role of the Zirconia Content on the Microstructure and Mechanical Properties
Authors: Naglieri Valentina , Palmero Paola , Montanaro Laura , Chevalier Jérôme
Published: May 2013

Alumina-zirconia (AZ) composites are attractive structural materials, which combine the high hardness and Young’s modulus of the alumina matrix with additional toughening effects, due to the zirconia dispersion. In this study, AZ composites containing different amounts of zirconia (in the range 5–20 vol %) were prepared by a wet chemical method, consisting on the surface coating of alumina powders by mixing them with zirconium salt aqueous solutions. After spray-drying, powders were calcined at 600 °C for 1 h. Green bodies were then prepared by two methods: uniaxial pressing of spray-dried granules and slip casting of slurries, obtained by re-dispersing the spray dried granulates. After pressureless sintering at 1500 °C for 1 h, the slip cast samples gave rise to fully dense materials, characterized by a quite homogeneous distribution of ZrO2 grains in the alumina matrix. The microstructure, phase composition, tetragonal to monoclinic transformation behavior and mechanical properties were investigated and are here discussed as a function of the ZrO2 content. The material containing 10 vol % ZrO2 presented a relevant hardness and exhibited the maximum value of KI0, mainly imputable to the t → m transformation at the crack tip.
Four New Citrinin Derivatives from a Marine-Derived Penicillium sp. Fungal Strain
Authors: Wang Mei , Lu Chun , Xu Qing , Song Si , Hu Zhi , Zheng Zhong
Published: May 2013

Four new citrinin derivatives, including two citrinin dimers and two citrinin monomer derivatives, were isolated and identified from a marine-derived fungal strain Penicillium sp. ML226 along with six known related compounds. Their structures were elucidated by spectroscopic and chemical methods. The new compounds showed modest cytotoxic activity against HepG-2 cell line and weak antimicrobial activity against Staphylococcus aureus.
Synthesis and Characterization of Oil-Chitosan Composite Spheres
Authors: Huang Keng-Shiang , Wang Chih-Yu , Yang Chih-Hui , Grumezescu Alexandru , Lin Yung-Sheng , Kung Chao-Pin , Lin I-Yin , Chang Yi-Ching , Weng Wei-Jie , Wang Wei-Ting
Published: May 2013

Oil-chitosan composite spheres were synthesized by encapsulation of sunflower seed oil in chitosan droplets, dropping into NaOH solution and in situ solidification. Hydrophilic materials (i.e., iron oxide nanoparticles) and lipophilic materials (i.e., rhodamine B or epirubicin) could be encapsulated simultaneously in the spheres in a one step process. The diameters of the prepared spheres were 2.48 ± 0.11 mm (pure chitosan spheres), 2.31 ± 0.08 mm (oil-chitosan composites), 1.49 ± 0.15 mm (iron-oxide embedded oil-chitosan composites), and 1.69 ± 0.1 mm (epirubicin and iron oxide encapsulated oil-chitosan composites), respectively. Due to their superparamagnetic properties, the iron-oxide embedded oil-chitosan composites could be guided by a magnet. A lipophilic drug (epirubicin) could be loaded in the spheres with encapsulation rate measured to be 72.25%. The lipophilic fluorescent dye rhodamine B was also loadable in the spheres with red fluorescence being observed under a fluorescence microscope. We have developed a novel approach to an in situ process for fabricating oil-chitosan composite spheres with dual encapsulation properties, which are potential multifunctional drug carriers.
One-Dimensional Coordination Polymers of Lanthanide Cations to Cucurbit[7]uril Built Using a Range of Tetrachloride Transition-Metal Dianion Structure Inducers
Authors: Liang Li-Li , Zhao Yi , Chen Kai , Xiao Xin , Clegg Jack , Zhang Yun-Qian , Tao Zhu , Xue Sai-Feng , Zhu Qian-Jiang , Wei Gang
Published: May 2013

A number of linear coordination polymers have been assembled from lanthanide cations (Ln3+) and cucurbit[7]uril (Q[7]) in the presence of [CuCl4]2−or [CoCl4]2− anions acting as inorganic structure inducers in HCl solution. X-ray diffraction analysis has revealed that they form three groups of isomorphous structures. Generally, the complexes of Q[7] with light lanthanide cations (those with atomic number below that of neodymium (Nd3+)) are in one group. The other two groups, in which the lanthanide cation has atomic number greater than that of europium (Eu3+), seem to follow no obvious rule. For example, the complexes of Q[7] with Eu3+ and Gd3+cations are in the second group in the presence of [CuCl4]2− anions, while they are in the third group in the presence of [CoCl4]2− anions. However, whatever group a given complex belongs to, they all show a common honeycomb-patterned supramolecular assembly, in which [CuCl4]2−or [CoCl4]2− anions form a honeycomb structure. The Ln3+ cations then coordinate to neighboring Q[7] molecules to form 1D coordination polymers that are inserted into the channels of the honeycomb framework, such that each individual coordination polymer is surrounded by [CuCl4]2−or [CoCl4]2− anions.
Electrical Model for Analyzing Chemical Kinetics, Lasing and Bio-Chemical Processes
Authors: Shahmoon Asaf , Zalevsky Zeev
Published: May 2013

In this paper we present the analogous electrical model for analyzing and determining the precise time dependence of concentrations in general first and zero order chemical reactions. In addition, the applicability of this analogous electrical model for investigating the optical and bio chemical processes is also presented. By constructing the proper analogous electrical circuit experimentally or with the help of special electrical software, the time behavior of the analyzed parameter even for extremely complicated processes can be obtained.
An Easy to Deploy Street Light Control System Based on Wireless Communication and LED Technology
Authors: Elejoste Pilar , Angulo Ignacio , Perallos Asier , Chertudi Aitor , Zuazola Ignacio , Moreno Asier , Azpilicueta Leire , Astrain José , Falcone Francisco , Villadangos Jesús
Published: May 2013

This paper presents an intelligent streetlight management system based on LED lamps, designed to facilitate its deployment in existing facilities. The proposed approach, which is based on wireless communication technologies, will minimize the cost of investment of traditional wired systems, which always need civil engineering for burying of cable underground and consequently are more expensive than if the connection of the different nodes is made over the air. The deployed solution will be aware of their surrounding’s environmental conditions, a fact that will be approached for the system intelligence in order to learn, and later, apply dynamic rules. The knowledge of real time illumination needs, in terms of instant use of the street in which it is installed, will also feed our system, with the objective of providing tangible solutions to reduce energy consumption according to the contextual needs, an exact calculation of energy consumption and reliable mechanisms for preventive maintenance of facilities.
Mobile Monitoring and Reasoning Methods to Prevent Cardiovascular Diseases
Authors: Hervás Ramón , Fontecha Jesús , Ausín David , Castanedo Federico , Bravo José , López-de-Ipiña Diego
Published: May 2013

With the recent technological advances, it is possible to monitor vital signs using Bluetooth-enabled biometric mobile devices such as smartphones, tablets or electric wristbands. In this manuscript, we present a system to estimate the risk of cardiovascular diseases in Ambient Assisted Living environments. Cardiovascular disease risk is obtained from the monitoring of the blood pressure by means of mobile devices in combination with other clinical factors, and applying reasoning techniques based on the Systematic Coronary Risk Evaluation Project charts. We have developed an end-to-end software application for patients and physicians and a rule-based reasoning engine. We have also proposed a conceptual module to integrate recommendations to patients in their daily activities based on information proactively inferred through reasoning techniques and context-awareness. To evaluate the platform, we carried out usability experiments and performance benchmarks.
Persépolis, Athènes et Sybaris: questions de monnayage et de chronologie
Authors: Vickers Michael
Published: May 2013

Reprenant l'examen des données numismatiques fournies par les dépôts de fondation découverts à Persépolis et par le trésor monétaire trouvé sur l'Acropole dans la même fosse que les Corés, l'auteur propose de rabaisser considérablement la date des premières « chouettes » athéniennes, ainsi que des sculptures « archaïques » et de la céramique à figures rouges. Il considère que ces monuments, comme les monnaies, doivent être attribués à la période de Thémistocle et de Cimon, juste après les Guerres Médiques.
Un Document nouveau sur le Néôrion et le Thesmophorion à Délos
Authors: Tréheux Jacques
Published: May 2013

Au compte délien IG, XI 2, 219, daté de 272 ou 271 avant J.-C., t'A. a raccordé le fragment 229, publié indépendamment dans le Corpus, et complété ainsi les 1. 18 à 37 du compte. Une révision des 1. 42-43 de la face .4 a rétabli la mention du Néôrion, curieusement omise par l'éditeur, dans un programme de vernissage à la paix (ἄλειψις) des édifices du sanctuaire : cette lecture nouvelle, prouvant que le Néôrion était déjà en service à la date du compte, écarte l'hypothèse de R. Vallois (AIID, I, p. 43), reprise récemment par G. Roux, selon laquelle la construction du Néôrion, entreprise par Démétrios Poliorcète et interrompue par sa mort prématurée, aurait été achevée par son fils, Antigonos Gonatas, pour y exposer le vaisseau amiral de sa victoire sur Ptolémée à Leucolla en Cos (au plus tôt 262 avant J.-C). La révision des 1. 44-45 du même compte a montré que les bâtiments du sanctuaire qui furent, en l'année du compte, l'objet d'un vernissage s'y succèdent dans l'ordre : Propylées, Néôrion, fontaine Minoè, Lètôon, Palestre, Thesmophorion. Les cinq premiers sont identifiés avec certitude, la situation du dernier est inconnue. En reportant sur le plan de Délos le programme de cette άλειψις on observe un itinéraire quasi rectiligne dont le prolongement conduit vers le Thesmophorion qu'on cherchera soit sur le rivage Nord-Est de la calanque de Skardhana, soit encore, mais moins probablement aux yeux de l'A., au bord des plages de la Synagogue.
Avulsion fragmentation of the tibial tuberosity apophysis and associated patellar tendon enthesopathy in a skeletally immature dog
Authors: Kalff S. , Parry A. , Whitehead M. , McKee W. M. , Brown G. W.
Published: May 2013

A 9.5-month-old, female entire, 31.3 kg crossbred dog was presented with a 12 week history of moderate weight-bearing right pelvic limb lameness. Radiographic, computed tomographic, and ultrasonographic imaging revealed progressive avulsion fragmentation of the right tibial tuberosity apophysis and a patellar tendon insertional enthesopathy without physeal involvement. Conservative management was successful in achieving a good clinical outcome. A progressive avulsion of the contralateral proximal tibial physes that occurred concurrently resulted in development of an excessive tibial plateau slope angle. The additional development of a moderate left distal femoral varus deformity was surgically corrected. This is the first report of a progressive, traction injury to the tibial tuberosity apophysis in a dog that appears clinically and radiographically very similar to Osgood-Schlatter disease in humans.
Effect of Epigallocatechin-3-Gallate on Graft-Versus-Host Disease
Authors: Choi Jaebok , Cooper Matthew L. , Ziga Edward D. , Ritchey Julie , Dipersio John F.
Published: May 2013

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is often complicated by alloreactive donor T-cell-mediated graft-versus-host disease (GvHD). The major polyphenol of green tea, epigallocatechin-3-gallate (EGCG), is an inhibitor of both DNA methyltransferase 1 (DNMT1) and signal transducer and activator of transcription 1 (STAT1), which are essential for induction of GvHD. Thus, in this report, we examine if in vivo administration of EGCG mitigates GvHD in several different animal models. While we concede that refinement of EGCG treatment might result in GvHD prevention, our results suggest that EGCG treatment might not be an effective therapy against GvHD in the clinic.
POSITIVE SOLUTIONS FOR SINGULAR SYSTEMS OF HIGHER-ORDER MULTI-POINT BOUNDARY VALUE PROBLEMS
Authors: Henderson Johnny , Luca Rodica
Published: May 2013

We investigate the existence of positive solutions for systems of singular nonlinear higher-order differential equations subject to multi-point boundary conditions.
Longitudinal Peripheral Blood Lymphocyte Subsets Correlate with Decreased Disease Activity in Juvenile Dermatomyositis
Authors: Ernste Floranne C. , Crowson Cynthia S. , de Padilla Consuelo Lopez , Hein Molly S. , Reed Ann M.
Published: May 2013

Objective:

To determine the clinical characteristics and subsets of peripheral blood lymphocytes (PBL), which correlate with decreased disease activity in patients with juvenile dermatomyositis (JDM).

Methods.

Peripheral blood mononuclear cells from 24 patients with JDM were collected at Mayo Clinic Rochester between 2007 and 2011. These were analyzed using fluorescence-activated cell sorting and flow cytometry. Clinical disease activity was determined by visual analog scales (VAS) collected in 2 consecutive visits and correlated with PBL subsets.

Results.

The change in CD3+CD69+ T cells correlated with the change in global VAS scores. The change in HLA-DR- CD11c+ myeloid dendritic cells also correlated with the change in extramuscular VAS scores. There were trends toward decreased levels of HLA-DR- CD11c+ cells with decreased muscle and global VAS scores, but these did not reach significance. The change in HLA-DR- CD123+ plasmacytoid dendritic cells negatively correlated with the change in muscle VAS scores. Although not statistically significant, decreased levels of CD3-CD16- CD56+ natural killer (NK) cells and HLA-DR- CD86+ myeloid dendritic cells, and increased levels of CD16+CD56- NK cells, correlated with decreased VAS scores.

Conclusion.

Changes in CD3+CD69+ T cells, HLA-DR- CD11c+ myeloid dendritic cells, and HLA-DR- CD123+ plasmacytoid dendritic cells are associated with improved clinical course in JDM and could be used as markers for disease activity, but findings need to be verified in a larger, independent cohort. Lack of significant differences among most of our PBL subsets suggests that lymphocyte phenotyping may be difficult to definitively correlate with disease activity in JDM.
Intraarticular and Systemic Inflammatory Profiles May Identify Patients with Osteoarthritis
Authors: Heard Bryan J. , Fritzler Marvin J. , Wiley J. Preston , McAllister Jenelle , Martin Liam , El-Gabalawy Hani , Hart David A. , Frank Cyril B. , Krawetz Roman
Published: May 2013

Objective.

To determine whether cytokine/chemokine profiles from synovial fluid and sera discriminate mild/moderate osteoarthritis (OA) from normal and severe OA cohorts.

Methods.

Multiplex technology was used to quantify expression levels for 42 cytokines in the synovial fluid of patients diagnosed with severe OA (n = 20) and mild/moderate OA (n = 12), as well as normal controls (n = 34). The same 42 cytokines were examined in serum samples of patients with severe OA (n = 26) and mild/moderate OA (n = 74) and normal individuals (n = 100). Treatment group comparisons followed by principal component analysis (PCA) and K-means clustering of the significantly different cytokines/chemokines revealed groupings of patients by physician diagnosis.

Results.

Differences in cytokine/chemokine levels were found between control, mild/moderate OA, and severe OA synovial fluid samples, as well as between normal and mild/moderate OA serum samples, and between control and severe OA serum samples. No differences were observed between mild/moderate and severe OA serum samples. Visual groupings based on PCA were validated by K-means analysis, with the best results obtained from the comparison of normal and mild/moderate OA serum samples with 96% of normal and 93% of mild/moderate OA samples accurately identified.

Conclusion.

Our study suggests that comparing the expression levels of cytokines/chemokines in synovial fluid and/or serum of patients with OA may have promise as a diagnostic platform to identify patients early in their disease course. This high-throughput low-cost assay may be able to provide clinicians with a diagnostic test to complement existing clinical and imaging modalities currently used to diagnose OA.
A Potential Suppressive Effect of Natural Antisense IL-1β RNA on Lipopolysaccharide-Induced IL-1β Expression
Authors: Lu Jiawei , Wu Xiurong , Hong Mao , Tobias Peter , Han Jiahuai
Published: May 2013

Although more than half of genomic loci are believed to have antisense transcription, whether antisense transcription is involved in cytokine expression has not been studied. In this study, we show that some loci of innate immunity related genes do have antisense transcripts. We investigated the effect of several antisense RNAs, including anti–4-1BBL, anti-p100, and anti–IL-1β, on their cognate sense gene’s expression in macrophages. We found that overexpression of antisense IL-1β transcript suppressed IL-1β expression. Anti–IL-1β is complementary to the sequence in the 5′ upstream region of the IL-1β promoter. Its mediated inhibition of IL-1β production occurred at the transcriptional level. Anti–IL-1β did not alter the methylation status of the IL-1β promoter. However, chromatin immunoprecipitation assays revealed that the anti–IL-1β transcript can change the chromatin structure of the IL-1β promoter by decreasing H3K4 trimethylation on the promoter, which is at least part of the mechanism underlying the reduced binding of RNA polymerase II to the IL-1β promoter upon anti–IL-1β expression. Our data suggest that some antisense transcripts of innate immunity-related genes play a role by regulating cytokine expression.
B Lymphocyte “Original Sin” in the Bone Marrow Enhances Islet Autoreactivity in Type 1 Diabetes–Prone Nonobese Diabetic Mice
Authors: Henry-Bonami Rachel A. , Williams Jonathan M. , Rachakonda Amita B. , Karamali Mariam , Kendall Peggy L. , Thomas James W.
Published: May 2013

Effective central tolerance is required to control the large extent of autoreactivity normally present in the developing B cell repertoire. Insulin-reactive B cells are required for type 1 diabetes in the NOD mouse, because engineered mice lacking this population are protected from disease. The Cg-Tg(Igh-6/Igh-V125)2Jwt/JwtJ (VH125Tg) model is used to define this population, which is found with increased frequency in the periphery of NOD mice versus nonautoimmune C57BL/6 VH125Tg mice; however, the ontogeny of this disparity is unknown. To better understand the origins of these pernicious B cells, anti-insulin B cells were tracked during development in the polyclonal repertoire of VH125Tg mice. An increased proportion of insulin-binding B cells is apparent in NOD mice at the earliest point of Ag commitment in the bone marrow. Two predominant L chains were identified in B cells that bind heterologous insulin. Interestingly, Vκ4-57-1 polymorphisms that confer a CDR3 Pro-Pro motif enhance self-reactivity in VH125Tg/NOD mice. Despite binding circulating autoantigen in vivo, anti-insulin B cells transition from the parenchyma to the sinusoids in the bone marrow of NOD mice and enter the periphery unimpeded. Anti-insulin B cells expand at the site of autoimmune attack in the pancreas and correlate with increased numbers of IFN-γ–producing cells in the repertoire. These data identify the failure to cull autoreactive B cells in the bone marrow as the primary source of anti-insulin B cells in NOD mice and suggest that dysregulation of central tolerance permits their escape into the periphery to promote disease.
Sialyltransferase ST3Gal-III Regulates Siglec-F Ligand Formation and Eosinophilic Lung Inflammation in Mice
Authors: Suzukawa Maho , Miller Marina , Rosenthal Peter , Cho Jae Youn , Doherty Taylor A. , Varki Ajit , Broide David
Published: May 2013

Sialic acid–binding, Ig-like lectin (Siglec)-F is highly expressed on mouse eosinophils and plays an important role in regulating levels of eosinophilic lung inflammation. In this study we investigated the mechanism of constitutive and inducible Siglec-F ligand expression by lung airway epithelial cells and inflammatory cells in wild-type (WT) and genetically altered mice (ST3Gal-III heterozygotes, Fuc-TIV/VII double null, STAT6 null). Flow cytometry demonstrated that Siglec-F ligands are constitutively expressed in vitro and in vivo in selected lung cell types (epithelial cells, eosinophils, macrophages, and mast cells, but not CD4, CD8, or B cells) and are induced in response to divergent stimuli, including innate stimuli (TLR ligands, Alternaria), Th2 cytokines (IL-4, IL-13), and adaptive immune stimuli (OVA allergen). Furthermore, studies of deficient mice demonstrated the greater importance of the sialyltransferase ST3Gal-III compared with fucosyltransferases Fuc-TIV/VII in the synthesis of the constitutive and inducible Siglec-F ligands by lung epithelial and nonepithelial cells. In keeping with this, ST3Gal-III heterozygote mice (deficient in expression of Siglec-F ligands) also had significantly enhanced OVA-induced eosinophilic airway inflammation associated with reduced eosinophil apoptosis. Reduced eosinophil apoptosis in the lung of ST3Gal-III–deficient mice is likely mediated by reduced epithelial expression of Siglec-F ligands as WT eosinophils (which highly express Siglec-F) cultured with ST3Gal-III–deficient epithelial cells (which do not express Siglec-F ligand) showed reduced eosinophil apoptosis compared with WT eosinophils cultured with WT epithelial cells. Overall, these studies demonstrate that ST3Gal-III plays an important role in Siglec-F ligand formation and eosinophil apoptosis with resultant effects on eosinophilic inflammation in the lung.
Antimicrobial susceptibility profiles of Staphylococcus intermedius isolates from clinical cases of canine pyoderma in South Africa
Authors: Blunt Catherine A. , Van Vuuren Moritz , Picard Jacqueline
Published: May 2013

Successful treatment of canine pyoderma has become compromised owing to the development of antimicrobial resistance with accompanying recurrence of infection. Canine skin samples submitted to a veterinary diagnostic laboratory for microbiological culture and sensitivity between January 2007 and June 2010, from which Staphylococcus intermedius was isolated, were selected for this investigation. Antimicrobial resistance of S. intermedius was most prevalent with reference to ampicillin followed by resistance to tetracycline and then potentiated sulphonamides. In general, antimicrobial resistance was low and very few methicillin-resistant isolates were detected. Temporal trends were not noted, except for ampicillin, with isolates becoming more susceptible, and potentiated sulphonamides (co-trimoxazole), with isolates becoming more resistant. In general, both the Kirby–Bauer disc diffusion and broth dilution minimum inhibitory concentration tests yielded similar results for the antimicrobial agents tested. The main difference was evident in the over-estimation of resistance by the Kirby–Bauer test for ampicillin, co-trimoxazole, penicillin and doxycycline. Knowledge of trends in bacterial resistance is important for veterinarians when presented with canine pyoderma. Analysis of antimicrobial susceptibility profiles of S. intermedius isolated from canine pyodermas will guide veterinarians’ use of the most appropriate agent and encourage prudent use of antimicrobials in companion animals.
Prevalence of low back pain and associated risk factors amongst adult patients presenting to a Nigerian family practice clinic, a hospital-based study
Authors: Ogunbode Adetola M. , Adebusoye Lawrence A. , Alonge Temitope O.
Published: May 2013

Background: Low back pain (LBP) is a common health problem with concomitant disability which has assumed a public health importance in our setting.Objectives: The aim of this study was to determine the prevalence of LBP and associated risk factors amongst adult patients attending the General Outpatients’ Clinic of the UniversityCollege Hospital in Ibadan, Nigeria.Method: This was a cross-sectional study of 485 respondents. A semi-structured questionnaire was used to obtain information on socio-demography, lifestyle, occupation and other riskfactors associated with LBP.Results: There were 288 (59.4%) female and 197 (40.6%) male respondents. The point prevalence of LBP was 46.8%. Occupational activities, previous back injury and tobacco smoking were significant associated factors for the total population. For the female respondents, logisticregression analysis showed that a waist circumference of 88 cm or more, dysmenorrhea,previous back injury and being engaged in an occupation were the most significant factors associated with LBP. However, previous back injury was the most significant factor associatedwith LBP for the male respondents.Conclusion: The prevalence of LBP amongst adult patients in our setting is high, with preventable and treatable predisposing factors. Public health efforts should be directed at educating people on occupational activities and lifestyle habits.
Contraceptive practices amongst HIV-positive women on antiretroviral therapy attending an ART clinic in South Africa
Authors: Oni Ezekiel E. , Ross Andrew , Van der Linde Stephan
Published: May 2013

Background: Effective contraceptive practices amongst HIV-positive women of reproductive age have been shown to reduce mother-to-child transmission of HIV by preventing unplanned pregnancies. However, most antiretroviral therapy (ART) programmes focus on treatment,neglecting comprehensive contraceptive services. This results in a high frequency of pregnancies amongst HIV-positive women attending the ART clinic of a regional hospital north of Durban.Objectives: This research aimed to explore contraceptive use amongst HIV-positive women attending an ART clinic by determining, (1) prevalence of contraceptive use, (2) pregnancy rate, (3) contraceptive preferences and (4) factors associated with contraceptive use.Methods: In this observational, analytical, cross-sectional study of 420 women, aged 15to 49 years, participants were selected by systematic random sampling. They completed standardised questionnaires.Results: Of all participants, 95% of the participants used contraception. Factors associated with contraceptive practice were knowledge of HIV status 292 (72.8%), health worker advice 84 (20.9%), and spousal insistence 33 (8.2%). Of the 130 women (31%) who had fallen pregnant whilst on ART, 73 (56.2%) said that the pregnancy had been unplanned, whilst 57 (43.8%) had wanted to fall pregnant because of: partner’s insistence (45.6%), desire for a child (36.8%),desire to conceal HIV status (15.8%), not wanting to die childless (5.3%), and death of aprevious child (1.8%).Conclusion: Contraceptive use amongst these women was high but the number of pregnancies is a cause for concern. Information regarding contraceptive use should therefore be providedat all ART clinics.
Preparing for export? Medical and nursing student migration intentions post-qualification in South Africa
Authors: George Gavin , Reardon Candice
Published: May 2013

Background: The migration of health professionals can have a profound impact on health systems around the globe. The International Organization for Migration’s (IOM) Mobility of Health Professionals Research Project (MoHProf) aimed to improve knowledge about the migration of healthcare professionals and understand migration intentions and factors influencing the migration of medical and nursing students.Objectives: The study aimed to determine the proportion of nursing and medical studentswho were intending to emigrate, their attitudes and beliefs about, and the factors influencing their decision to emigrate.Method: This study was conducted at three medical schools and one nursing school in SouthAfrica (n = 298) amongst 260 medical and 38 nursing students. One hundred and twenty-five students were in the final year of their studies and 143 were in their prefinal year. Thirty students did not indicate the year of their studies. Every student present on the day of data collection completed a questionnaire comprising psychometric and survey-based questions. Descriptive and inferential statistics were used to analyse the data.Results: More than a third (37%) of the respondents intended to work or specialise abroad.The majority of medical (58.9%) and nursing (66.6%) students intended to leave SA within five years of completing their medical or nursing studies. The perception of poor working conditions within the health sector, such as long work hours, high patient loads, inadequate resources and occupational hazards, influenced medical students to consider emigrating from South Africa.Conclusion: The high number of medical and nursing students intending to emigrate requires a reassessment of effectiveness of retention strategies for doctors and nurses in the South African healthcare system and actions to improve working conditions in the public healthcare sector.
Antiviral Stratagems against HIV-1 Using RNA Interference (RNAi) Technology
Authors: Vlachakis Dimitrios , Tsiliki Georgia , Pavlopoulou Athanasia , Roubelakis Maria G. , Tsaniras Spyridon Champeris , Kossida Sophia
Published: May 2013

The versatility of human immunodeficiency virus (HIV)-1 and its evolutionary potential to elude antiretroviral agents by mutating may be its most invincible weapon. Viruses, including HIV, in order to adapt and survive in their environment evolve at extremely fast rates. Given that conventional approaches which have been applied against HIV have failed, novel and more promising approaches must be employed. Recent studies advocate RNA interference (RNAi) as a promising therapeutic tool against HIV In this regard, targeting multiple HIV sites in the context of a combinatorial RNAi-based approach may efficiently stop viral propagation at an early stage. Moreover, large high-throughput RNAi screens are widely used in the fields of drug development and reverse genetics. Computer-based algorithms, bioinformatics, and biostatistical approaches have been employed in traditional medicinal chemistry discovery protocols for low molecular weight compounds. However, the diversity and complexity of RNAi screens cannot be efficiently addressed by these outdated approaches. Herein, a series of novel workflows for both wet- and dry-lab strategies are presented in an effort to provide an updated review of state-of-the-art RNAi technologies, which may enable adequate progress in the fight against the HIV-1 virus.
Ocean acidification from 1997 to 2011 in the subarctic western North Pacific Ocean
Authors: Wakita M. , Watanabe S. , Honda M. , Nagano A. , Kimoto K. , Matsumoto K. , Kawakami H. , Fujiki T. , Kitamura M. , Sasaki K. , Sasaoka K. , Nakano Y. , Murata A.
Published: May 2013

Abstract. Rising atmospheric CO2 contents have led to greater CO2 uptake by the oceans, lowering both pH due to increasing hydrogen ions and CaCO3 saturation states due to declining carbonate ion (CO32−). Here, we used previously compiled data sets and new data collected in 2010 and 2011 to investigate ocean acidification of the North Pacific western subarctic gyre. In winter, the western subarctic gyre is a source of CO2 to the atmosphere because of convective mixing of deep waters rich in dissolved inorganic carbon (DIC). We calculated pH in winter mixed layer from DIC and total alkalinity (TA), and found that it decreased at the rate of −0.001 ± 0.0004 yr−1 from 1997 to 2011. This decrease rate is slower than that expected under condition of seawater/atmosphere equilibration, and it is also slower than the rate in the subtropical regions (−0.002 yr−1). The slow rate is caused by a reduction of CO2 emission in winter due to an increase in TA. Below the mixed layer, the calcite saturation horizon (~185 m depth) shoaled at the rate of 2.9 ± 0.9 m yr−1 as the result of the declining CO32− concentration (−0.03 ± 0.01 μmol k−1yr−1). Between 200 m and 300 m depth, pH decline during the study period (−0.0051 ± 0.0010 yr−1) was larger than ever reported in the open North Pacific. This enhanced acidification rate below the calcite saturation horizon reflected not only the uptake of anthropogenic CO2 but also the increase in the decomposition of organic matter evaluated from the increase in AOU, which suggests that the dissolution of CaCO3 particles increased.
Climate of the last millennium: ensemble consistency of simulations and reconstructions
Authors: Bothe O. , Jungclaus J. H. , Zanchettin D. , Zorita E.
Published: May 2013

Abstract. Are simulations and reconstructions of past climate and its variability consistent with each other? We assess the consistency of simulations and reconstructions for the climate of the last millennium under the paradigm of a statistically indistinguishable ensemble. In this type of analysis, the null hypothesis is that reconstructions and simulations are statistically indistinguishable and, therefore, are exchangeable with each other. Ensemble consistency is assessed for Northern Hemisphere mean temperature, Central European mean temperature and for global temperature fields. Reconstructions available for these regions serve as verification data for a set of simulations of the climate of the last millennium performed at the Max Planck Institute for Meteorology. Consistency is generally limited to some sub-domains and some sub-periods. Only the ensemble simulated and reconstructed annual Central European mean temperatures for the second half of the last millennium demonstrates unambiguous consistency. Furthermore, we cannot exclude consistency of an ensemble of reconstructions of Northern Hemisphere temperature with the simulation ensemble mean. If we treat simulations and reconstructions as equitable hypotheses about past climate variability, the found general lack of their consistency weakens our confidence in inferences about past climate evolutions on the considered spatial and temporal scales. That is, our available estimates of past climate evolutions are on an equal footing but, as shown here, inconsistent with each other.
Critical impacts of global warming on land ecosystems
Authors: Ostberg S. , Lucht W. , Schaphoff S. , Gerten D.
Published: May 2013

Abstract. Globally increasing temperatures may have unmanageable impacts on terrestrial, aquatic and marine ecosystems. Quantifying impacts worldwide and systematically as a function of global warming is critical to substantiate the ongoing international negotiations on climate mitigation targets. Here we present a macro-scale analysis of climate change impacts on terrestrial ecosystems based on newly developed sets of climate scenarios featuring a step-wise sampling of global mean temperature increase between 1.5 and 5 K by 2100. These are processed by a biogeochemical model (LPJmL) to derive an aggregated metric of simultaneous biogeochemical and structural shifts in land surface properties which we interpret as a proxy for the risk of shifts and possibly disruptions in ecosystems. Our results show a substantial risk of climate change to transform terrestrial ecosystems profoundly. Nearly no area of the world is free from such risk, unless strong mitigation limits warming to around 2 degrees above preindustrial level. Even then, most climate models agree that up to one fifth of the land surface may experience at least moderate change, primarily at high latitudes and high altitudes. If countries fulfill their current emissions pledges, resulting in roughly 3.5 K of warming, this area expands to cover half the land surface, including the majority of tropical forests and savannas and the boreal zone. Due to differences in regional patterns of climate change the area potentially at risk of severe ecosystem change considering all AOGCMs is up to 2.5 times as large as for a single AOGCM.
Modeling regional evaporation through ANFIS incorporated solely with remote sensing data
Authors: Chang F.-J. , Sun W.
Published: May 2013

Abstract. The study aims to model regional evaporation that possesses the ability to present the spatial distribution of evaporation across the whole Taiwan by the adaptive network-based fuzzy inference system (ANFIS) based solely on remote sensing data. The remote sensing data used in this study consist of Landsat image products including Enhanced Vegetation Index (EVI) and land surface temperature (LST). The model construction is designed through two types of data allocation (temporal and spatial) driven with the same ten-year data of EVI and LST derived from Landsat images. Evidences indicate the estimation model based solely on remotely sensed data can effectively detect the spatial variation of evaporation and appropriately capture the evaporation trend with acceptable errors of about 1 mm day−1. The results also demonstrate the composite of EVI and LST input to the proposed estimation model improves the accuracy of estimated evaporation values as compared with the model using LST as the only input, which reveals EVI indeed benefits the estimation process. The results suggest Model-T (temporal input allocation) is suitable for making island-wide evaporation estimation while Model-S (spatial input allocation) is suitable for making evaporation estimation at ungauged sites. An island-wide evaporation map for the whole study area (Taiwan Island) is then derived. It concludes the proposed ANFIS model incorporated solely with remote sensing data can reasonably well generate evaporation estimation and is reliable as well as easily applicable for operational estimation of evaporation over large areas where the network of ground-based meteorological gauging stations is not dense enough or readily available.
Satellite based analysis of recent trends in the ecohydrology of a semi-arid region
Authors: Gokmen M. , Vekerdy Z. , Verhoef W. , Batelaan O.
Published: May 2013

Abstract. We present a regional framework for an integrated and spatiotemporally distributed assessment of human-induced trends in the hydrology and the associated ecological health of a semi-arid basin where both human activities (i.e. agriculture) and natural ecosystems are highly groundwater dependent. To achieve this, we analysed the recent trends (from year 2000 to 2010) in precipitation, evapotranspiration (actual and potential) and vegetation greenness (i.e. NDVI) using a combination of satellite and ground-based observations. The trend assessment was applied for the semi-arid Konya basin (Turkey), one of the largest endorheic basins in the world. The results revealed a consistent increasing trend of both yearly evapotranspiration (totally 63 MCM yr−1 from croplands) and mean NDVI (about 0.004 NDVI yr−1 in irrigated croplands), especially concentrating in the plain part of the basin, while no significant trends were observed for the precipitation and potential evapotranspiration variables. On the contrary, a consistent decreasing trend of both yearly evapotranspiration (totally −2.1 MCM yr−1) and mean NDVI (−0.001 NDVI yr−1) was observed in the wetlands, which also cannot be explained by trends in precipitation and potential evapotranspiration. The emerging picture suggest that the greening trend of the vegetation and increasing of evapotranspiration in the plain are related to land cover changes (i.e. conversion into irrigated croplands) and to the intensification of the supplementary irrigation for agriculture, which in turn caused drying out of the some of the wetlands and the natural vegetation which mostly depend on the groundwater, the main source of irrigation water as well. Our study presented an example of the utility of spatially and temporally continuous RS data in assessing the regional trends in hydrological and ecological variables and their interactions in a spatially distributed manner in a semi-arid region, which can also be adapted to other regions. Such spatiotemporally distributed analysis at the basin level is particularly important considering that most of the water management interventions also take place at this scale.
TOWARDS 4D VIRTUAL CITY RECONSTRUCTION FROM LIDAR POINT CLOUD SEQUENCES
Authors: Józsa O. , Börcs A. , Benedek C.
Published: May 2013

Abstract. In this paper we propose a joint approach on virtual city reconstruction and dynamic scene analysis based on point cloud sequences of a single car-mounted Rotating Multi-Beam (RMB) Lidar sensor. The aim of the addressed work is to create 4D spatio-temporal models of large dynamic urban scenes containing various moving and static objects. Standalone RMB Lidar devices have been frequently applied in robot navigation tasks and proved to be efficient in moving object detection and recognition. However, they have not been widely exploited yet for geometric approximation of ground surfaces and building facades due to the sparseness and inhomogeneous density of the individual point cloud scans. In our approach we propose an automatic registration method of the consecutive scans without any additional sensor information such as IMU, and introduce a process for simultaneously extracting reconstructed surfaces, motion information and objects from the registered dense point cloud completed with point time stamp information.
BEYOND HAND-CRAFTED FEATURES IN REMOTE SENSING
Authors: Tokarczyk P. , Wegner J. D. , Walk S. , Schindler K.
Published: May 2013

Abstract. A basic problem of image classification in remote sensing is to select suitable image features. However, modern classifiers such as AdaBoost allow for feature selection driven by the training data. This capability brings up the question whether hand-crafted features are required or whether it would not be enough to extract the same quasi-exhaustive feature set for different classification problems and let the classifier choose a suitable subset for the specific image statistics of the given problem. To be able to efficiently extract a large quasi-exhaustive set of multi-scale texture and intensity features we suggest to approximate standard derivative filters via integral images. We compare our quasi-exhaustive features to several standard feature sets on four very high-resolution (VHR) aerial and satellite datasets of urban areas. We show that in combination with a boosting classifier the proposed quasi-exhaustive features outperform standard baselines.
SINGLE TREE DETECTION FROM AIRBORNE LASER SCANNING DATA USING A MARKED POINT PROCESS BASED METHOD
Authors: Zhang J. , Sohn G. , Brédif M.
Published: May 2013

Abstract. Tree detection and reconstruction is of great interest in large-scale city modelling. In this paper, we present a marked point process model to detect single trees from airborne laser scanning (ALS) data. We consider single trees in ALS recovered canopy height model (CHM) as a realization of point process of circles. Unlike traditional marked point process, we sample the model in a constraint configuration space by making use of image process techniques. A Gibbs energy is defined on the model, containing a data term which judge the fitness of the model with respect to the data, and prior term which incorporate the prior knowledge of object layouts. We search the optimal configuration through a steepest gradient descent algorithm. The presented hybrid framework was test on three forest plots and experiments show the effectiveness of the proposed method.
Radio-frequency probes of Antarctic ice at South Pole
Authors: Besson D. , Kravchenko I.
Published: May 2013

Abstract. Using hardware developed for the ARA (Askaryan Radio Array) particle astrophysics experiment, we herein report on the amplitude and temporal characteristics of polarized surface radar echo data collected in South Polar ice using radio sounding equipment with 0.5-ns echo-time sampling. We observe strong echoes at 6, 9.6, 13.9, 17, and 19 μs following vertical pulse emission from the surface, corresponding to reflectors in the upper half of the ice sheet. The synchronicity of those echoes for all broadcast azimuthal polarizations affirms the lack of observable birefringence over the upper half of the ice sheet. Of the five strongest echoes, three exhibit an evident amplitude correlation with the local surface ice flow direction, qualitatively consistent with measurements in East Antarctica. Combined with other radio echo sounding data, we conclude that observed birefringent asymmetries at South Pole are generated entirely in the lower half of the ice sheet. By contrast, birefringent asymmetries are observed at shallow depths in East Antarctica.
The Effects of rhBMP-2 and Treg/Th17 Functional Disequilibrium in Uremic Patients with Cardiovascular Complication after Maintenance Hemodialysis
Authors: Danyan Chen , Xiaolong Huang , Song Lu , Hua Gan , Weixue Tang , Ke Liu
Published: May 2013

Objectives

We compared the correlation of regulatory T cell (Treg) and Th17 cell function disequilibrium with calcification in uremic patients on maintenance hemodialysis (MHD) with healthy controls, and investigated if their influence possibly increased the development and outcome of cardiovascular complications in uremic patients after MHD.

Methods

The extent of coronary artery calcification was assessed by coronary artery calcification scoring (CACS) in uremic patients with and without adverse cardiovascular events after MHD (MHD group 1 vs. MHD group 2, respectively). Peripheral blood mononuclear cells were incubated with rhBMP-2 as positive control. The Treg/Th17 cell frequencies, Foxp3 ROR-γt mRNA expressions, and MIP 3α/CCL20 concentrations were measured.

Results

The CACS score was significantly higher in MHD group 1 as compared group 2. In comparison with controls, rhBMP-2 upregulates Treg/Th17 functional disequilibrium in uremic patients, displayed higher Treg and Th17 frequencies, Foxp3 and ROR-γt expressions, and MIP3α/CCL20 concentrations. However, the up-regulations of Treg frequencies and Foxp3 expressions were significant in controls but not in MHD patients. It was also observed that Treg/Th17 functional disequilibrium was not only correlated with rhBMP-2 state but also consistent with the cardiovascular complications. Moreover, the CACS was negatively correlated with Treg cell frequencies but positively correlated with Th17 cell frequencies and MIP3α/CCL20 concentrations.

Conclusions

Function disequilibrium of Treg/Th17 was related to the degree of the rhBMP-2 state. Function disequilibrium of the Treg/Th17 might act synergistically with rhBMP-2 in the high incidence of immune-mediated cardiovascular complications after MHD.
Neoliberalism and Qatari preschools: A comparative study of England and Qatar
Authors: Althani Tamader , Romanowski Michael
Published: May 2013

Qatar is in the midst of a massive systematic reform designed to convert its schools and Ministry of Education into a world-class competitive educational system according toEducation for a New Era. Influenced by neoliberalism as a dominant ideology that treats education as just another service to be bought and sold on the market, Qatar is one of the most active importers of foreign education providers in the world and this adoption or borrowing of educational methods has drastically shaped the educational landscape in therein. Neoliberalism and the adoption of educational methods or strategies have influenced teacher licensing, curriculum, professional development and daily classroom instruction. One expanse of the educational system that has received little attention is the preschool classroom. This paper reports the findings from nonparticipant observations of preschool classrooms in the England and Qatar, followed by personal reflections and experiences regarding Qatari preschool education. The purpose of the study is to examine the policies and practices in the Qatari preschool system and to determine to what degree preschool pedagogical practices are similar to those practices found in England. The analysis illustrates that there are some teaching methods and pedagogical polices that reflect the British system, but teachers in Qatar still require additional professional development in order to adapt and utilize these pedagogical strategies and policies to better meet the Qatari context.