bluuebunny/crossref_metadata_2025 huggingface dataset:
An Investigation Comparing the Efficacy of Topical Ocular Application of Tacrolimus and Cyclosporine in Dogs
Authors: Hendrix Diane V .H. , Adkins Elizabeth A. , Ward Daniel A. , Stuffle Jamie , Skorobohach Brian
Published: May 2011

The purpose of this paper was to determine the efficacy and safety of topical tacrolimus, compared to cyclosporine, for treating keratoconjunctivitis sicca (KCS) in dogs. This study was a two-phase, randomized, controlled, masked clinical trial. Phase 1 evaluated ophthalmic 0.03% tacrolimus in normal dogs. Ocular examinations were performed daily. Phase 2 evaluated the efficacy of tacrolimus in treating KCS. Half the dogs received 2% cyclosporine A; the others received 0.03% tacrolimus, both diluted in olive oil. Four ophthalmic examinations were done over 12 weeks. There was no significant difference between groups in phase I. In phase 2, there was no significant difference in Schirmer tear test I (STT) results between the two groups, and both groups had a significant increase in STT over time. Both drugs were effective in increasing the STT in dogs naïve to lacrimostimulants. Tacrolimus was effective in increasing the STT in 4 dogs currently nonresponsive to cyclosporine.
Indices of Kidney Damage and Cardiovascular Disease Risk Factors in a Semiurban Community of Iloye, South-West Nigeria
Authors: Awobusuyi J. O. , Kukoyi O. O. , Ibrahim M. A. , Atiba M.
Published: May 2011

Health screening exercises are important, as they enable early detection of diseases in individual subjects and also enable data collection, useful in estimating disease burden in the community. This paper describes the findings of a health screening exercise conducted in a semiurban population of Iloye, by the Rotary Club of Ota, Ogun State, Western Nigeria, as a part of its community-oriented services and projects. Three hundred and twenty six community members were screened during the exercise. There were 189 (57.97%) females and 137 (42.03%) males, with a mean age of 43.5 ± 14.88 yrs. Urinary abnormality and/or creatinine clearance less than 90 mls/min was detected in 147 (45.09%) participants. 99 (30.37%) participants had proteinuria, 16 (4.91%) had haematuria, and 5 (1.53%) participants had both haematuria and proteinuria. Eight (2.45%) participants had GFR less than 60 mls/min. Elevated blood pressure was found in 152 (46.63%), while 3 (0.9%) participants had diabetes, 71 (21.8%) were obese, 16 (4.9%) had hypercholesterolaemia, and 3 (0.9%) had hypertriglyceridaemia. Prevalence of both smoking and alcohol consumption was 6 (1.84%). It was concluded that the prevalence of indices of kidney damage and cardiovascular risk factors is high in Iloye community.
Salmonella enteritidisInfection Complicated by Acute Myocarditis: A Case Report and Review of the Literature
Authors: Papamichalis Panagiotis , Argyraki Katerina , Papamichalis Michail , Loukopoulos Argyris , Dalekos Georgios N. , Rigopoulou Eirini I.
Published: May 2011

Salmonella spp.is the cause of commonly encountered infections, with seasonal pattern of occurrence and worldwide distribution. Some of the clinical manifestations such as gastroenteritis and bacteremia are common, whereas others like mycotic aneurysms and osteomyelitis are infrequent especially in immunocompetent patients. Salmonella has been rarely described as a cause of myocarditis in the literature. We describe a case of an 18-year-old previously healthy male patient with myocarditis afterSalmonella enteritidisinfection. Clinical manifestations and diagnostic approach of this severe complication are discussed with a review of the literature.
Arterial Stiffness in Chronic Kidney Disease: The Usefulness of a Marker of Vascular Damage
Authors: Bellasi Antonio , Ferramosca Emiliana , Ratti Carlo
Published: May 2011

Increased arterial stiffness is a marker of vasculopathy in chronic kidney disease (CKD) patients, suggesting a significant cardiovascular damage. Detection of arterial stiffness provides physicians with useful prognostic information independent of traditional cardiovascular (CV) risk factors. In addition, this knowledge may help guide appropriate therapeutic choices and monitor the effectiveness of antihypertensive therapies. We review the relationship between arterial stiffness and CKD, as well as the prognostic implications of increased arterial stiffness and the potential therapeutic strategies to ameliorate arterial compliance and outcome in CKD.
The associations of humorous coping styles, affective states, job demands and job control with the frequency of upper respiratory tract infection
Authors: Doosje Sibe , De Goede Martijn P.M. , Van Doornen Lorenz J.P. , Van de Schoot Rens
Published: May 2011

Orientation: There is some evidence that job demands and job resources such as job control and humorous coping may contribute to the risk of upper respiratory tract infections (URTI).Research purpose: The purpose of this study was to test a model including these variables as well as job-related affect, in order to explore their role in the explanation of the frequency of upper respiratory tract infection.Motivation of the study: This study has been conducted in order to extend our understanding of the role of traditional variables like job demands and job control with humorous coping styles and affective variables with regard to the explanation of the frequency of URTI.Research design, approach and method: A sample of 2094 employees filled out questionnaires assessing job demands, job control, generic (MSHS-C), antecedent-focused and responsefocused humorous coping (QOHC) and job-related affect (JAWS).Main findings: Job demands were indirectly related to the frequency of upper respiratory tract infections, mediated by their relationships with job control and negative job-related affect. Generic and response-focused humorous coping were less relevant for the explanation of the frequency of upper respiratory tract infections than the presumably ‘healthy’ antecedentfocused humorous coping style. The latter showed a negative association with negative jobrelated affect. The frequency of upper respiratory tract infections was better predicted by job control and negative job-related affect than by humorous coping, in the expected directions.Practical/managerial implication: These findings may have practical relevance for the improvement of stress management interventions in organisations.Contribution/value-add: Although it was shown that healthy humorous coping does contribute to decreases in upper respiratory tract infection, job demands, job resources and negative affective state seem the most important predictors.
Methotrexate Revisited—in Recurrent Head and Neck Cancer
Authors: Banipal R.P.S. , Mahajan M.K.
Published: May 2011

Aims

Response of single agent chemotherapy in improving quality of life in patients with recurrent head and neck cancers.

Methods and material

This is a study of the 18 patients with advanced cancers of head and neck, who had failed earlier attempts of radical treatment with Surgery, Radiotherapy ± chemotherapy and have residual or recurrent tumours, were treated with single agent Injection Methotrexate 50 mg/m2 weekly. Follow up visit complaints and clinical examination details were recorded. History regarding pain, speech and diet was collected for every visit. Severity of pain was divided with the National Cancer Institute's Common Terminology Criteria for Adverse Events (CTCAE) version 3.0 pain scales. Symptom control was done with analgesics, antiemetic and infection control.

Results

Weekly single agent chemotherapy with injection Methotrexate has significantly improved the quality of life of patients. 38.8% of patients have shown good response with decrease in the tumour bulk by more than 50% and other 39% of patients have stable disease on Injection Methotrexate. 22.2% patients have shown disease progression on single agent chemotherapy. Overall 83.3% patients have shown improvement in Quality of life in terms of symptomatic control. After 6 weekly treatments with injection methotrexate 63% patients were pain free with 16% patients reported decrease in pain. 87.5% of patients have shown improvement in speech and diet. Improvement in symptoms has shown decrease in depression in cancer patients. Grade 3 toxicity observed was Neutropenia (11.1%), anaemia (11.1%) and Mucositis (16.6%) which was managed adequately. Median survival with good quality of life is 5.4 months.

Conclusions

Single agent methotrexate chemotherapy on an out-patient basis can provide good quality of life. Decrease in pain along with improvement in speech and diet has shown decrease in incidence of depression and overall positive impact on psychosocial status. Few cases have shown sustained regression of gross disease adding to maintained quality of life with better socio-economic compliance.
THE PRESERVATION OF ANCIENT ARABIC MANUSCRIPTS: A REFLECTION ON SOME SELECTED PUBLIC REPOSITORIES IN NORTHERN NIGERIA
Authors: Bala Salisu
Published: May 2011

The three repositories covered by this paper, the Arewa House Arabic Manuscript repository, the National Jos Museum Arabic Manuscript Collection, and the Gidan Dan Hausa Arabic Manuscripts Collection in Kano, maintain great collections of ancient Arabic manuscripts on diverse subjects. The repositories are in jeopardy due to poor storage systems, lack of capacity building on the part of the staff, and above all laxity on the part of policy makers. The question of procuring and preserving Nigerian Arabic manuscripts for proper utilization by researchers has been a major source of concern to both Nigerian and foreign scholars in the last fifty years or so. Although a lot of progress has been made in this regard since the pioneering days of Professors Abdullahi Smith, K. O. Dike, Murray Last, and others, the three Arabic manuscript repositories covered by this study continue to function in bad conditions, ranging from a lack of paper conservation supplies, poor storage systems, and a complete absence of digitization equipment for proper archiving. However, there is now a defi nite consensus among researchers and other stakeholders in this field on the urgency of the matter and, happily, a decisive change of attitude towards the fate of the Arabic / Ajami Manuscripts in most of the repositories of northern Nigeria. A spate of conferences and workshops were organized in quick succession in the last two years and an impressive number of research publications were presented for serious discussions on virtually all aspects of the problems facing the Arabic manuscripts repositories.
A THEMATIC EXPOSITION OF THE NUPE AJAMI MANUSCRIPT HERITAGE OF NORTHERN NIGERIA
Authors: Ndagi Muhammad Umaru
Published: May 2011

After the establishment of the Sokoto Caliphate in Nigeria early in the nineteenth century, various groups of Muslims adopted Ajami1 for transcribing their indigenous languages. The spread of Islam in Nupeland, like in other parts of the Muslim world, was thus accompanied by the growth of a local Islamic literature written in Arabic script. This essay calls attention to the Nupe Ajami manuscripts of northern Nigeria, with a view to clarifying their central themes. Previous studies reveal that the large intellectual output by the scholars of the Sokoto jihad includes not only Islamic religious sciences but also medicine, law, and administration. But researchers have not paid attention to the contents of Nupe Ajami manuscripts. I have chosen ten manuscripts for analysis in this essay. Seven of them are from the collection at the Northern History Research Scheme (NHRS), a postgraduate library in the department of history at Ahmadu Bello University, Zaria. The remaining three manuscripts are from collections in private hands. I have cited only a few lines from each, and have provided their English transliterations and translations, followed by a concise commentary. By bringing this particular literary heritage to the attention of scholars, I hope this essay will stimulate research on Nupe Ajami that could broaden our understanding of the Islamic intellectual traditions of northern Nigeria
Coastal precipitation formation and discharge based on TRMM observations
Authors: Heiblum R. H. , Koren I. , Altaratz O.
Published: May 2011

Abstract. The interaction between breezes and synoptic gradient winds creates persistent convergence zones nearby coastlines. The low level convergence of moist air promotes the dynamical and microphysical processes responsible for the formation of clouds and precipitation. Our work focuses on the winter seasons of 1998–2011 in the Eastern Mediterrenean. During the winter the Mediterrenean sea is usually warmer than the adjacent land, resulting in frequent occurence of land breeze that opposes the commom synoptic winds. Using rain-rate vertical profiles from the Tropical Rainfall Measurement Mission (TRMM) satellite, we examined the spatial and temporal distribution of average hydrometeor mass in clouds as a funtion of the distance from coastlines. Results show that coastalines in the Eastern Mediterrenean are indeed favored areas for precipitation formation and discharge. The intra-seasonal and diurnal changes in the distribution of hydrometeor mass indicate that the land breeze is most likely the main responsible mechanism behind our results.
Accumulation of aerosols over the Indo-Gangetic plains and southern slopes of the Himalayas: distribution, properties and radiative effects during the 2009 pre-monsoon Season
Authors: Gautam R. , Hsu N. C. , Tsay S. C. , Lau K. M. , Holben B. , Bell S. , Smirnov A. , Li C. , Hansell R. , Ji Q. , Payra S. , Aryal D. , Kayastha R. , Kim K. M.
Published: May 2011

Abstract. We examine the distribution of aerosols and associated optical/radiative properties in the Gangetic-Himalayan region from simultaneous radiometric measurements over the Indo-Gangetic Plains (IGP) and the foothill/slopes of the Himalayas during the 2009 pre-monsoon season. Enhanced dust transport extending from the Southwest Asian arid regions into the IGP, results in seasonal mean (April–June) aerosol optical depths of over 0.6 – highest over southern Asia. The influence of dust loading is greater over the western IGP as suggested by pronounced coarse mode peak in aerosol size distribution and spectral single scattering albedo (SSA). The transported dust in the IGP, driven by prevailing westerly airmass, is found to be more absorbing (SSA550 nm ~0.89) than the near-desert region in NW India (SSA550 nm ~0.91) suggesting mixing with carbonaceous aerosols in the IGP. On the contrary, significantly reduced dust transport is observed over eastern IGP and foothill/elevated slopes in Nepal where strongly absorbing haze is prevalent, associated with upslope transport of pollution, as indicated by low values of SSA (0.85–0.9 for the wavelength range of 440–1020 nm), suggesting presence of more absorbing aerosols compared to IGP. Assessment of the radiative impact of aerosols over NW India suggests diurnal mean reduction in solar radiation fluxes of 19–23 Wm−2 at surface (12–15 % of the surface solar insolation). Based on limited observations of aerosol optical properties during the pre-monsoon period and comparison of our radiative forcing estimates with published literature, there exists spatial heterogeneity in the regional aerosol forcing, associated with the absorbing aerosol distribution over northern India, with both diurnal mean surface forcing and forcing efficiency over the IGP exceeding that over NW India. Additionally, the role of the seasonal progressive buildup of aerosol loading and water vapor is investigated in the observed net aerosol forcing over NW India. The radiative impact of water vapor is found to amplify the net regional aerosol radiative forcing suggesting that the two exert forcing in tandem leading to enhanced surface cooling. It is suggested that water vapor contribution should be taken into account while assessing aerosol forcing impact for this region and other seasonally similar environments.
Retrieval of water vapor vertical distributions in the upper troposphere and the lower stratosphere from SCIAMACHY limb measurements
Authors: Rozanov A. , Weigel K. , Bovensmann H. , Dhomse S. , Eichmann K.-U. , Kivi R. , Rozanov V. , Vömel H. , Weber M. , Burrows J. P.
Published: May 2011

Abstract. This study describes the retrieval of water vapor vertical distributions in the upper troposphere and lower stratosphere (UTLS) altitude range from space-borne observations of the scattered solar light made in limb viewing geometry. First results using measurements from SCIAMACHY (Scanning Imaging Absorption spectroMeter for Atmospheric CHartographY) aboard ENVISAT (Environmental Satellite) are presented here. In previous publications, the retrieval of water vapor vertical distributions has been achieved exploiting either the emitted radiance leaving the atmosphere or the transmitted solar radiation. In this study, the scattered solar radiation is used as a new source of information on the water vapor content in the UTLS region. A recently developed retrieval algorithm utilizes the differential absorption structure of the water vapor in 1353–1410 nm spectral range and yields the water vapor content in the 11–25 km altitude range. In this study, the retrieval algorithm is successfully applied to SCIAMACHY limb measurements and the resulting water vapor profiles are compared to in situ balloon-borne observations. The results from both satellite and balloon-borne instruments are found to agree typically within 10 %.
Near-surface profiles of aerosol number concentration and temperature over the Arctic Ocean
Authors: Held A. , Orsini D. A. , Vaattovaara P. , Tjernström M. , Leck C.
Published: May 2011

Abstract. Temperature and particle number concentration profiles were measured at small height intervals above open and frozen leads and snow surfaces in the central Arctic. The device used was a gradient pole designed to investigate potential particle sources over the central Arctic Ocean. The collected data was fitted according to basic logarithmic flux-profile relationships to calculate the sensible heat flux and particle deposition velocity. Independent measurements by the eddy covariance technique were conducted at the same location. General agreement was observed between the two methods when logarithmic profiles could be fitted to the gradient pole data. In general, snow surfaces behaved as weak particle sinks with a maximum deposition velocity vd = 1.3 mm s−1 measured with the gradient pole. The lead surface behaved as a weak particle source before freeze-up with an upward flux Fc = 5.7 × 104 particles m−2 s−1, and as a relatively strong heat source after freeze-up, with an upward maximum sensible heat flux H = 13.1 W m−2. Over the frozen lead, however, we were unable to resolve any significant aerosol profiles.
Photospheric magnetic vortex structures
Authors: Shelyag S. , Fedun V. , Keenan F. P. , Erdélyi R. , Mathioudakis M.
Published: May 2011

Abstract. Using direct numerical magneto-hydrodynamic (MHD) simulations, we demonstrate the evidence of two physically different types of vortex motions in the solar photosphere. Baroclinic motions of plasma in non-magnetic granules are the primary source of vorticity in granular regions of the solar photosphere, however, there is a significantly more efficient mechanism of vorticity production in strongly magnetised intergranular lanes. These swirly motions of plasma in intergranular magnetic field concentrations could be responsible for the generation of different types of MHD wave modes, for example, kink, sausage and torsional Alfvén waves. These waves could transport a relevant amount of energy from the lower solar atmosphere and contribute to coronal plasma heating.
Nitrogen uptake by phytoplankton in the Atlantic sector of the Southern Ocean during late austral summer
Authors: Joubert W. R. , Thomalla S. J. , Waldron H. N. , Lucas M. I.
Published: May 2011

Abstract. As part of the Bonus-Good Hope (BGH) campaign, 15N-labelled nitrate, ammonium and urea uptake measurements were made along the BGH transect from Cape Town to ~ 60° S in late austral summer, 2008. Our results are categorised according to distinct hydrographic regions defined by oceanic fronts and open ocean zones. Nitrogen uptake (ρN) in the oligotrophic Subtropical Zone (STZ) was dominated by ρ urea, which contributed up to 70 % of ρN. High regenerated ρN in the STZ resulted in low f-ratios (f = 0.2). Size fractionated chlorophyll data showed that the greatest contribution (>50 %) of picophytoplankton (<2 μm) were found in the STZ, consistent with a community based on regenerated production. The Subantarctic Zone (SAZ) showed the greatest total integrated ρN (10.3 mmol m−2 d−1), mainly due to enhanced light and nutrient supply within an anticyclonic eddy observed in this region. A decrease in the contribution of smaller size classes to the phytoplankton community was observed with increasing latitude, concurrent with a decrease in the contribution of regenerated production. Higher f-ratios observed in the SAZ (f = 0.49), Polar Frontal Zone (f = 0.41) and Antarctic Zone (f = 0.45) relative to the STZ (f = 0.2), indicate a higher contribution of ρNO3 relative to total ρN and potentially higher export production. Greater contribution of regenerated uptake to ∫ρN in the northern sector of the cruise resulted from increased ambient regenerated nutrient concentrations, shallow mixed layers in the north (~40 m) relative to the regions further south (~100 m). Higher ρ∫N rates also correspond with higher surface iron concentrations. No clear correlation was observed between carbon export estimates derived from new production and 234Th flux. In addition, export derived from 15N estimates were 2–20 times greater than those based on 234Th flux. Variability in the magnitude of export is likely due to intrinsically different methods, compounded by differences in integration time scales for the two proxies of carbon export.
Perturbation of convection-permitting NWP forecasts for flash-flood ensemble forecasting
Authors: Vincendon B. , Ducrocq V. , Nuissier O. , Vié B.
Published: May 2011

Abstract. Mediterranean intense weather events often lead to devastating flash-floods. Extending the forecasting lead times further than the watershed response times, implies the use of numerical weather prediction (NWP) to drive hydrological models. However, the nature of the precipitating events and the temporal and spatial scales of the watershed response make them difficult to forecast, even using a high-resolution convection-permitting NWP deterministic forecasting. This study proposes a new method to sample the uncertainties of high-resolution NWP precipitation forecasts in order to quantify the predictability of the streamflow forecasts. We have developed a perturbation method based on convection-permitting NWP-model error statistics. It produces short-term precipitation ensemble forecasts from single-value meteorological forecasts. These rainfall ensemble forecasts are then fed into a hydrological model dedicated to flash-flood forecasting to produce ensemble streamflow forecasts. The verification on two flash-flood events shows that this forecasting ensemble performs better than the deterministic forecast. The performance of the precipitation perturbation method has also been found to be broadly as good as that obtained using a state-of-the-art research convection-permitting NWP ensemble, while requiring less computing time.
Landsat TM and ETM+ derived snowline altitudes in the Cordillera Huayhuash and Cordillera Raura, Peru, 1986–2005
Authors: McFadden E. M. , Ramage J. , Rodbell D. T.
Published: May 2011

Abstract. The Cordilleras Huayhuash and Raura are remote glacierized ranges in the Andes Mountains of Peru. A robust assessment of modern glacier change is important for understanding how regional change affects Andean communities, and for placing paleo-glaciers in a context relative to modern glaciation and climate. Snowline altitudes (SLAs) derived from satellite imagery are used as a proxy for modern (1986–2005) local climate change in a key transition zone in the Andes. Clear sky, dry season Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM+) satellite images from 1986–2005 were used to identify snowline positions, and their altitude ranges were extracted from an Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) digital elevation model (DEM). Based on satellite records from 31 glaciers, average snowline altitudes (SLAs), an approximation for the equilibrium line altitude (ELA), for the Cordillera Huayhuash (13 glaciers) and Cordillera Raura (18 glaciers) from 1986–2005 were 5051 m a.s.l. from 1986–2005 and 5006 m a.s.l. from 1986–2002, respectively. During the same time period, the Cordillera Huayhuash SLA experienced no significant change while the Cordillera Raura SLA rose significantly from 4947 m a.s.l. to 5044 m a.s.l.
Evaluation of “Indigenous Absorbed ELISA Kit” for the Estimation of Seroprevalence ofMycobacterium aviumSubspeciesparatuberculosisAntibodies in Human Beings in North India
Authors: Singh A. V. , Singh S. V. , Verma D. K. , Yadav R. , Singh P. K. , Sohal J. S.
Published: May 2011

In present pilot study aimed to estimate, presence ofMycobacterium aviumsubspeciesparatuberculosis(MAP) antibodies in the human serum samples originating from North India using “Indigenous absorbed ELISA kit” (ELISA kit). The phase I, “ELISA kit” was optimized using protoplasmic antigen from native isolate of MAP “Indian Bison type” recovered from the biopsies of Crohn's disease patients. The phase II, sensitivity and specificity of the kit were estimated as 40.0 and 83.3%, respectively, when evaluated in 40 human serum samples (5 Crohn's disease and 22 ulcerative colitis patients and 13 healthy human subjects) with defined MAP status with respect to stool culture. Seroprevalence of MAP antibodies was higher in CD patients (80.0%) as compared to ulcerative colitis patients (4.5%) and normal human subjects (15.3%). The phase III, seroprevalence of MAP antibodies was estimated as 23.4%, on the basis of the screening of 452 human serum samples (without history) from different geographical regions of North India. Region-wise, 34.0, 33.3, 32.8, 25.0, 23.0, 17.7, and 12.5% samples were positive from the states of Punjab, Uttarakhand, New Delhi, Himachal Pradesh, Haryana, Uttar Pradesh and Jammu and Kashmir, respectively. Study reported moderately higher presence of MAP antibodies in human population, which necessitates programs to reduce the bioburden of MAP in the environment and in animal population.
Microchimerism: Sharing Genes in Illness and in Health
Authors: Knippen Maureen A.
Published: May 2011

Microchimerism is
defined as the presence of two genetically
distinct cell populations in the same
individual. It can arise from several causes
including the bidirectional transfer of cells
between mother and fetus during pregnancy, twin-to-twin transfer in utero, from organ
transplantation, and blood transfusion.
Recently, scientists have found male fetal cells
from decades earlier imbedded in tissues and
organs of some women with autoimmune diseases.
The significance of these findings as they
relate to real or potential health implications
in autoimmune diseases, graft-versus-host
reactions, and transfusion complications is
discussed here.
Relationship between Younger Age, Autoimmunity, Cardiometabolic Risk, Oxidative Stress, HAART, and Ischemic Stroke in Africans with HIV/AIDS
Authors: Longo-Mbenza Benjamin , Longokolo Mashi Murielle , Lelo Tshikwela Michel , Mokondjimobe Etienne , Gombet Thierry , Ellenga-Mbolla Bertrand , Nge Okwe Augustin , Kangola Kabangu Nelly , Mbungu Fuele Simon
Published: May 2011

Background and Purpose. It now appears clear that both HIV/AIDS and antiretroviral therapy (HAART) use are associated with higher risk of cardiovascular disease such as stroke. In this study, we evaluated the prevalence, the risk factors, and the cardiometabolic comorbidities of stroke in HIV/AIDS Central African patients.Methods. This hospital-based cross-sectional study collected clinical, laboratory, and imaging data of black Central African heterosexual, intravenous drug nonuser, and HIV/AIDS patients.Results. There were 54 men and 62 women, with a female to male ratio of 1.2 : 1. All were defined by hypercoagulability and oxidative stress. Hemorrhagic stroke was reported in 1 patient, ischemic stroke in 17 patients, and all stroke subtypes in 18 patients (15%). Younger age <45 years , autoimmunity , and metabolic syndrome defined by IDF criteria were associated with ischemic stroke.Conclusions. Clustering of several cardiometabolic factors, autoimmunity, oxidative stress, and lifestyle changes may explain accelerated atherosclerosis and high risk of stroke in these young black Africans with HIV/AIDS. Prevention and intervention programs are needed.
Comparison of the Corrosion Behavior of Coated and Uncoated Magnesium Alloys in an In Vitro Corrosion Environment
Authors: Seitz Jan‐Marten , Collier Kelly , Wulf Eric , Bormann Dirk , Bach Friedrich‐Wilhelm
Published: May 2011

The in vitro degradation of magnesium alloys with various alloying elements, the effect of coatings, and the impact of an altered experimental environment are investigated. LANd442 and Nd2 alloys are subjected to a continuously moving environment during an immersion test allowing flowing SBF. Applying an MgF2coating to the alloys increases the corrosion resistance of LANd442 but has no effect on the corrosion rate of Nd2 within the period of investigation. It leads to a more‐even degradation with less pitting corrosion in the early stages of corrosion. A bioglass coating on Nd2 increases the corrosion rate. The mass loss, volume loss, and loss in maximum force all show the same trends as the specimens degrade over time.
Influence of Impact on the Mechanical Behaviour of the Gamma‐Based TiAl Alloy TNBV3B
Authors: Gebhard S. , Peters P. , Roth‐Fagaraseanu D. , Voggenreiter H.
Published: May 2011

The quasi‐static and fatigue behavior after impact of the TiAl alloy TNBV3B produced via three different processing routes—cast, forged and extruded—has been studied on flat and airfoil‐like shaped specimens making use of ballistic impact experiments. For impacts resulting in cracks the behavior can be described using a linear‐elastic fracture mechanics approach. The residual strength is described on the basis of the fracture toughness. The residual fatigue strength of impact‐cracked specimens is estimated on the basis of the threshold for crack growth of the TNBV3B alloys. However, when there is no visible crack or when the crack length is below the size of the deformed impact area, residual stresses and micro‐damage play a dominating role making the linear‐elastic fracture mechanics approach invalid. The deformation hardened zone in TiAl has been studied making use of micro‐hardness tests showing their extension and the degrees of deformation for different impact energies.
Efficient Immobilization of Yeast Transketolase on Layered Double Hydroxides and Application for Ketose Synthesis
Authors: Benaissi Karima , Hélaine Virgil , Prévot Vanessa , Forano Claude , Hecquet Laurence
Published: May 2011

Transketolase (TK) from S. cerevisiae was successfully immobilized on layered double hydroxides (LDH) using simple, affordable and efficient adsorption and coprecipitation based immobilization procedures. Optimization of the preparation was performed using zinc aluminium nitrate (Zn2Al‐NO3) and magnesium aluminium nitrate (Mg2Al‐NO3) LDH as immobilization supports, and the protein‐to‐LDH weight ratio (Q) was varied. The highest immobilization yields (98–99%) and highest relative specific activities (4.2–4.4 U⋅mg−1 for the immobilized enzyme compared to 4.5 U⋅mg−1 for the free enzyme) were both achieved when using a protein‐to‐LDH weight ratio (Q) of 0.38. Efficient lyophilization of the LDH‐TK bionanocomposites thus synthesized was proven to allow easy use and storage of the supported TK with no significant loss of activity over a three‐month period. The kinetic parameters of the LDH‐TK enzyme were comparable to those of the free TK. The LDH‐TK enzyme was finally tested for the synthesis of L‐erythrulose starting from hydroxypyruvate lithium salt (Li‐HPA) and glycolaldehyde (GA) as substrates. L‐erythrulose was characterized and obtained with an isolated yield of 56% similar to that obtained with free TK. The reusability of the LDH‐TK biohybrid material was then investigated, and we found no loss of enzymatic activity over six cycles.
An Efficient Route to Both Enantiomers of allo‐Threonine by Simultaneous Amino Acid Racemase‐Catalyzed Isomerization of Threonine and Crystallization
Authors: Würges Kerstin , Mackfeld Ursula , Pohl Martina , Lütz Stephan , Wilhelm Susanne , Wiechert Wolfgang , Kubitzki Tina
Published: May 2011

We present an efficient method for the production of D‐ and L‐allo‐threonine (allo‐Thr) with very high purity by enzymatic isomerization of L‐ or D‐threonine (Thr) and simultaneous crystallization. Isomerization of Thr to allo‐Thr is catalyzed by a purified amino acid racemase (AArac12996) from Pseudomonas putida NBRC12996, which can easily be obtained from a recombinant E. coli strain by secretion into the medium and subsequent anion exchange chromatography. Crystallization of D‐ and L‐allo‐Thr was performed in a repetitive batch mode over a period of up to 55 days at 30 °C. Total amounts of 30.8 g D‐allo‐Thr and 32.4 g L‐allo‐Thr were obtained with a very good diastereomeric excess of deD‐allo>99.2% and deL‐allo>98.4%, respectively, and in good yields (D‐allo‐Thr: 83%, L‐allo‐Thr: 79%). The enzyme’s remarkable high stability under process conditions resulted in enzyme specific yields of 2.56 g D‐allo‐Thr per mg AArac12996 and 1.62 g L‐allo‐Thr per mg AArac12996. In contrast to chemical multi‐step syntheses of allo‐Thr, our process consists of only one enzyme‐catalyzed reaction step with simultaneous product crystallization. The process is performed under low energy consumption (30 °C, atmospheric pressure) in water and avoids the use and production of any toxic or harmful compounds. Recovery of the enantiomerically pure products is performed by simple filtration which reduces downstream processing significantly compared to chromatographic methods which are usually applied.
Practical Synthesis of 2‐Arylacetic Acid Esters via Palladium‐ Catalyzed Dealkoxycarbonylative Coupling of Malonates with Aryl Halides
Authors: Song Bingrui , Rudolphi Felix , Himmler Thomas , Gooßen Lukas J.
Published: May 2011

A new palladium‐based system was developed that catalyzes the coupling of aryl halides with diethyl malonates in the presence of mild bases. In the course of the reaction, the intermediately formed diethyl arylmalonate is directly converted into the arylacetic acid ester via liberation of carbon dioxide and an alkanol. This cross‐coupling/dealkoxycarbonylation process provides an efficient and high‐yielding synthetic entry to diversely functionalized arylacetic acid esters. Two complementary protocols were developed, one of which is optimal for electron‐rich, the other for electron‐poor aryl halides. Both make use of low loadings of palladium(0) bis(dibenzylideneacetone) (0.5 mol%)/tri‐tert‐butylphosphonium tetrafluoroborate (1.1 mol%) as the catalyst and diethyl malonate as the reaction solvent. The new procedures are particularly effective for sterically hindered substrates.
How tufted capuchin monkeys (cebus apellaspp) and common chimpanzees (Pan troglodytes) align objects to surfaces: insights into spatial reasoning and implications for tool use
Authors: Fragaszy Dorothy M. , Stone Brian W. , Scott Nicole M. , Menzel Charles
Published: May 2011

This report addresses phylogenetic variation in a spatial skill that underlies tool use: aligning objects to a feature of a surface. Fragaszy and Cummins‐Sebree's [Behavioral and Cognitive Neuroscience Reviews 4:282–306, 2005] model of relational spatial reasoning and Skill Development and Perception–Action theories guided the design of the study. We examined how capuchins and chimpanzees place stick objects of varying shapes into matching grooves on a flat surface. Although most individuals aligned the long axis of the object with the matching groove more often than expected by chance, all typically did so with poor precision. Some individuals managed to align a second feature, and only one (a capuchin monkey) achieved above‐chance success at aligning three features with matching grooves. Our findings suggest that capuchins and chimpanzees do not reliably align objects along even one axis, and that neither species can reliably or easily master object placement tasks that require managing two or more spatial relations concurrently. Moreover, they did not systematically vary their behavior in a manner that would aid discovery of the affordances of the stick–surface combination beyond sliding the stick along the surface (which may have provided haptic information about the location of the groove). These limitations have profound consequences for the forms of tool use we can expect these individuals to master. Am. J. Primatol. 73:1012–1030, 2011. © 2011 Wiley‐Liss, Inc.
Mehrfachkatalyse durch zwei chirale Einheiten: eine weitere Dimension in der asymmetrischen Synthese
Authors: Piovesana Susy , Scarpino Schietroma Daniele M. , Bella Marco
Published: May 2011

In diesem Kurzaufsatz werden asymmetrische Reaktionen vorgestellt, die durch zwei unterschiedliche chirale Katalysatoren vermittelt werden (chirale Mehrfachkatalyse). Diese zunächst eigenwillig anmutende Methode ermöglicht tatsächlich eine schnelle, mehrdimensionale Optimierung und Feinabstimmung des Katalysesystems, das zur Ausführung einer bestimmten Umsetzung erforderlich ist. Hier werden dieses junge Konzept und seine möglichen Anwendungen erläutert.
Multiple Catalysis with Two Chiral Units: An Additional Dimension for Asymmetric Synthesis
Authors: Piovesana Susy , Scarpino Schietroma Daniele M. , Bella Marco
Published: May 2011

This Minireview focuses on asymmetric reactions mediated by two distinct chiral catalysts (chiral multiple catalysis). Initially, this approach appears unconventional, but indeed it allows a fast multidimensional optimization and fine‐tuning of the catalytic system required to perform a given transformation. Herein, this emerging concept is presented and its potential applications are highlighted.
In Vivo Solid‐Phase Microextraction in Metabolomics: Opportunities for the Direct Investigation of Biological Systems
Authors: Vuckovic Dajana , Risticevic Sanja , Pawliszyn Janusz
Published: May 2011

Sample preparation has a strong impact on the quality of metabolomics studies. The use of solid‐phase microextraction (SPME), particularly its in vivo format, enables the capture of a more representative metabolome and presents opportunities to detect low‐abundance, short‐lived, and/or unstable species not easily captured by traditional methods. The technique is ideally suited for temporal, spatial, and longitudinal studies of the same living system, as well as multicompartmental studies of the same organism. SPME is useful for the investigation of biological systems ranging in complexity from cells to mammalian tissues. Selected examples are highlighted in this Minireview in order to place the technique within the context of conventional methods of sample preparation for metabolomics.
Numerical investigation on effects of interphase force closures on liquid‐phase turbulence and microbubbles distribution in vertical upward channel bubbly flow
Authors: Pang Mingjun , Wei Jinjia , Yu Bo
Published: May 2011

Fully understanding mechanisms of the phase distribution and modulations of bubbles on the liquid‐phase turbulence is very crucial for practical applications of bubbly flows. In this paper, influences of different interphase forces on both of them were widely investigated with an Euler–Lagrange model in a vertical upward channel bubbly flow laden with microbubbles. The flow field was simulated by using direct numerical simulations (DNS), while the bubble dynamics were fully analyzed by integration of Newtonian equations of motion taking into account of four different combinations of interphase forces. The phase distribution and turbulence statistics of the liquid phase were comprehensively analyzed for all testing cases. The results show that the local void fraction profiles for different testing cases are different, whereas profiles of the turbulent statistics for all cases have a similar distributing trend with different magnitudes. It can be concluded from the present results that the drag force, the lift force, and the added mass force have a comparatively important influence on the local void fraction profile and the liquid‐phase turbulence. In contrast, the influence of the pressure gradient force seems to be extremely small. Copyright © 2011 Curtin University of Technology and John Wiley & Sons, Ltd.
Electropolymerization of a new 4‐(2,5‐Di‐2‐thiophen‐2‐yl‐pyrrol‐1‐yl)‐tetra substituted nickel phthalocyanine derivative
Authors: Yavuz Arzu , Bezgin Çarbaş Buket , Aras Leyla , Önal Ahmet M.
Published: May 2011

A new tetrakis 4‐(2,5‐di‐2‐thiophen‐2‐yl‐pyrrol‐1‐yl) substituted nickel phthalocyanine (NiPc‐SNS) was synthesized and characterized by elemental analysis, Fourier Transform Infrared (FT‐IR), and UV–vis spectroscopies. The electrochemical polymerization of this newly synthesized NiPc‐SNS was performed in dichloromethane (DCM)/tetrabutylammonium perchlorate (TBAP) solvent/electrolyte couple. An insoluble film was deposited on the electrode surface, both during repetitive cycling and constant potential electrolysis at 0.85 V. Resulting polymer film, P(NiPc‐SNS), was characterized utilizing UV–vis and FT‐IR spectroscopic techniques and its electrochemical behavior was investigated via cyclic voltammetry (CV). Spectroelectrochemical behavior of the polymer film on indium tin oxide (ITO) working electrode was investigated by recording the electronic absorption spectra, in situ, in monomer‐free electrolytic solution at different potentials and it is found that the P(NiPc‐SNS) film can be reversibly cycled between 0.0 and 1.1 V and exhibits electrochromic behavior; dark olive green in the neutral and dark blue in the oxidized states with a switching time of 1.98 s. Furthermore, the band gap of P(NiPc‐SNS) was calculated as 2.27 eV from the onset of π–π* transition of the conjugated backbone. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Poly(vinyl alcohol)‐based polymeric membrane: Preparation and tensile properties
Authors: Dong Qiang , Liu Junsheng , Yao Chao , Shao Guoquan
Published: May 2011

A series of poly(vinyl alcohol) (PVA)‐based single‐layer organic polymeric membranes were prepared via the crosslinking of PVA with different amounts of formaldehyde. Meanwhile, for comparison, both a three‐layer organic polymeric membrane and a hybrid composite membrane were also prepared by the layer‐upon‐layer method. Their thermal stability and tensile properties were investigated to examine the effect of crosslinking on the membrane performances. Thermogravimetric analysis and differential scanning calorimetry thermal analyses showed that the thermal degradation temperature of the single‐layer crosslinked membrane C reached up to 325°C. Tensile testing indicated that the three‐layer organic polymeric membrane E had excellent tensile strength among these single‐layer and three‐layer membranes. The swelling properties revealed that the swelling degree value of these membranes decreased with an increase in methanol concentration; this suggests that they were not easily swollen by the methanol solution, which is meaningful for the separation of organic mixtures. Field emission scanning electron microscopy images exhibited that the crosslinking of functional groups impacted their structures and confirmed that their mechanical properties were related to their structures. These findings suggest that the crosslinking of functional groups is an effective method for adjusting the tensile strength of PVA‐based organic polymeric membranes and related hybrid composite membranes. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Magnetic and electric responsive hydrogel–magnetic nanocomposites for drug‐delivery application
Authors: Reddy N. Narayana , Mohan Y. Murali , Varaprasad K. , Ravindra S. , Joy P. A. , Raju K. Mohana
Published: May 2011

Magnetic and electrically responsive hydrogel networks were developed for drug‐delivery applications. The hydrogel matrices were synthesized by the polymerization of acrylamide monomer in the presence of carboxymethylcellulose (CMC) or methylcellulose (MC) with N,N‐methylenebisacrylamide, a crosslinker with the redox initiating system ammonium persulfate/tetramethylethylenediamine. The magnetic nanoparticles were generated throughout these hydrogel matrices by an in situ method by the incorporation of iron ions and their subsequent reduction with ammonia. A series of hydrogel–magnetic nanocomposites (HGMNCs) were developed with various CMC and MC compositions. The synthesized HGMNCs were characterized with spectral (Fourier transform infrared and ultraviolet–visible spectroscopy), X‐ray diffraction, thermal, and microscopy methods. These HGMNCs contained iron oxide (Fe3O4) nanoparticles with an average particle size of about 22 nm, as observed by transmission electron microscopy. The dielectrical properties of the pure hydrogel (HG); the hydrogel loaded with iron ions, or the hydrogel iron‐ion composite (HGIC); and the HGMNCs were measured. These results suggest that HGMNCs exhibited higher dielectric constants compared to HG and HGICs. The curcumin loading and release characteristics were also measured for HG, HGIC, and HGMNC systems. These data revealed that there was a sustained release of curcumin from HGMNCs because of the presence of magnetic nanoparticles in the hydrogel networks. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Controlled aggregation of colloidal particles for toner applications
Authors: Turner Alyson J. , Nair Smitha , Lai Zhen , Cheng Chieh‐Min , Bhatia Surita R.
Published: May 2011

Micrometer‐sized particles were formed by controlled aggregation of carboxylated polystyrene colloidal spheres having a mean diameter of about 200 nm with a commercial cationic coagulant. To identify the parameters governing the size and structure of the aggregates, the aggregate size distribution was studied over a period of time with dynamic light scattering. The effect of the particle concentration, pH, and ionic strength on the aggregation behavior was investigated. The coagulant concentration used for present studies was 5 parts per hundred on the basis of the polystyrene particles and the particle concentrations used were 10–15%. The particle size distribution for the latex suspensions was also investigated with a 10% aluminum sulfate [Al2(SO4)3·14H2O] solution as a model coagulant. With the commercial coagulant, aggregation was found to be slower at lower pH than at neutral pH. At pH 6, the particles started to aggregate within minutes and form aggregates of about 1000 nm. We expected that lowering the pH would reduce interparticle repulsive forces and enhance the collision efficiency. However, at a lower pH of 2, the aggregation process slowed down. Increasing the ionic strength at neutral pH led to a broader aggregate size distribution, and the population of larger aggregates increased. The suspensions with the model coagulant showed similar behavior. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011