bluuebunny/crossref_metadata_2025 huggingface dataset:
Initial Assessment of the Acceptability of a Push-Pull Aedes aegypti Control Strategy in Iquitos, Peru and Kanchanaburi, Thailand
Authors: Paz-Soldan Valerie A. , Plasai Valaikanya , Morrison Amy C. , Rios-Lopez Esther J. , Guedez-Gonzales Shirly , Grieco John P. , Mundal Kirk , Chareonviriyaphap Theeraphap , Achee Nicole L.
Published: February 2011

As part of a larger research program evaluating chemical threshold levels for a Push-Pull intervention to reduce man-vector (Aedes aegypti) contact, this qualitative study explored local perceptions and strategies associated with mosquito control within dengue-endemic communities in Peru and Thailand. Focus groups were used to provide preliminary information that would identify possible public acceptance issues to the Push-Pull strategy in each site. Nine focus group discussions (total of 102 individuals) conducted between September 2008 and March 2009 examined several themes: 1) current mosquito control practices; 2) perceptions of spatial repellency and contact irritancy versus killing mosquitoes; and 3) initial perceptions toward mosquito host-seeking traps. Results indicate participants use household-level strategies for insect control that reveal familiarity with the concept of spatial repellent and contact irritant actions of chemicals and that placing traps in the peridomestic environment to remove repelled mosquitoes was acceptable. Preliminary evidence suggests a Push-Pull strategy should be well accepted in these locations. These results will be beneficial for developing future large scale push-pull interventions and are currently being used to guide insecticide application strategies in (entomological) proof-of-concept studies using experimental huts.
Experience with Extrarenal Manifestations of Hemorrhagic Fever with Renal Syndrome in a Tertiary Care Hospital in South Korea
Authors: Park Kyung Hwa , Kang Yong Un , Kang Seung-Ji , Jung Young-Sun , Jang Hee-Chang , Jung Sook-In
Published: February 2011

Reports on the clinical entity of hemorrhagic fever with renal syndrome (HFRS) have focused on acute renal failure. Data on the extrarenal manifestations are limited primarily to case reports. In this study, protean extrarenal manifestations involving the major organs occurred in one-third of patients with HFRS during various stages (i.e., febrile phase through diuretic phase). Pancreatobiliary manifestations and major bleeding occurred in 11% and 10% of patients, respectively. Cardiovascular and central nervous system manifestations developed during the febrile or oliguric phase, whereas pancreatobiliary manifestations and major bleeding were detected even in the diuretic phase. Thus, close monitoring of and additional knowledge about various extrarenal manifestations are needed.
Spontaneous Postpartum Clearance of Plasmodium falciparum Parasitemia in Pregnant Women, Benin
Authors: Bottero Julie , Briand Valérie , Agbowai Carine , Doritchamou Justin , Massougbodji Achille , Cot Michel
Published: February 2011

The question of malaria in the postpartum period is controversial. Malaria was investigated during a randomized trial of intermittent preventive treatment in pregnancy in Benin. Women infected at delivery were tested for parasitemia in the early postpartum period; they had not received treatment unless they were symptomatic. Among the 35 of 1,346 infected women, parasitologic follow-up results could not be interpreted in 15 because they were treated for symptoms, 18 cleared parasitemia spontaneously within five days postpartum, and 2 had a strong decrease in parasitemia before being treated. Because the placenta is the privileged site for sequestration of parasites, it facilitates their persistence during pregnancy, and its elimination may rapidly induce their clearance.
Seroprevalence to Coxiella burnetii Among Residents of the Hunter New England Region of New South Wales, Australia
Authors: Islam Aminul , Ferguson John , Givney Rod , Graves Stephen
Published: February 2011

Exposure to Coxiella burnetii is a risk in the Hunter New England (HNE) region of New South Wales (NSW), Australia, based on yearly reported cases of Q fever. We assessed seroprevalence of phase II antibodies to C. burnetii by indirect immunofluorescence assay (IFA; screening at 1/50 dilution) of residents of 24 local government areas (LGA) of the HNE region of NSW. A total of 2,438 randomly selected sera sent to the Hunter Area Pathology Service for routine diagnostic purposes (not Q fever testing) during the period of 2006–2009 were tested. The overall seroprevalence in sample group was 7%. The proportion of males (59%) was higher than females (41%). In age distribution, the largest proportion (37%) of seropositives was in the > 60 years age group. Lower prevalence was observed in 0–9 years (1%) and 10–19 years (5%) age groups. The seroprevalence in different LGAs varied between 0.5% and 22%. It was highest in Guyra (22%), Gunnedah (21%), Tenterfield (18%), and Narrabri (16%), with Newcastle (0.5%), Port Stephens (2%), Lake Macquarie (3%), and Singleton (3%) being the lowest. In most of the LGAs, seroprevalence was between 6% and 12%. This report indicates a considerable exposure to C. burnetii of residents in rural areas of the HNE region and is consistent with the high notification rate for Q fever in this part of Australia.
Emergence of Community-Associated Methicillin-Resistant Staphylococcus aureus Carriage in Children in Cambodia
Authors: Nickerson Emma K. , Wuthiekanun Vanaporn , Kumar Varun , Amornchai Premjit , Wongdeethai Nattavut , Chheng Kheng , Chantratita Narisara , Putchhat Hor , Thaipadungpanit Janjira , Day Nicholas P. , Peacock Sharon J.
Published: February 2011

We previously described the first reported isolation of methicillin-resistant Staphylococcus aureus (MRSA) (a case series of pediatric community-associated MRSA infections) in Cambodia. We define the rate of pediatric MRSA carriage in the same population and characterize the associated bacterial genotypes by using pulsed-field gel electrophoresis and multilocus sequence typing. A prospective cohort study of MRSA carriage conducted over one month at the Angkor Hospital for Children, Siem Reap, Cambodia, identified MRSA carriage in 87 (3.5%) of 2,485 children who came to the outpatient department, and 6 (4.1%) of 145 inpatients, including at least two with cases of nosocomial acquisition. Genotyping of all 93 MRSA isolates resolved 5 genotypes. Most (91%) isolates were assigned to sequence type 834. Only 28 (32%) of 87 MRSA carriers identified in the outpatient department had no history of recent healthcare contact. The study findings have important implications for healthcare in a setting where diagnostic microbiology and access to antimicrobial drugs with efficacy against MRSA are limited.
Evaluation of the NS1 Rapid Test and the WHO Dengue Classification Schemes for Use as Bedside Diagnosis of Acute Dengue Fever in Adults
Authors: Chaterji Shera , Allen John Carson , Chow Angelia , Leo Yee-Sin , Ooi Eng-Eong
Published: February 2011

Because healthcare facilities in many dengue endemic countries lack laboratory support, early dengue diagnosis must rely on either clinical recognition or a bedside diagnostic test. We evaluated the sensitivity and specificity of the 1997 and 2009 World Health Organization (WHO) dengue classification schemes and the NS1 strip test in acute sera from 154 virologically confirmed dengue patients and 200 patients with other febrile illnesses. Both WHO classification schemes had high sensitivity but lacked specificity. The NS1 strip test had high specificity, but its sensitivity was significantly lower in secondary compared with primary dengue infections. Differences in viral serotypes did not affect the performance of any of the three diagnostic approaches. Taken collectively, our findings indicate that the 1997 WHO dengue case definition can be used to exclude dengue, and the NS1 strip test can be used to confirm dengue infection, although the latter should be interpreted with caution in regions where secondary dengue infection is prevalent.
Prevention of Malaria during Pregnancy: Assessing the Effect of the Distribution of IPTp Through the National Policy in Benin
Authors: Port Agnès Le , Cottrell Gilles , Dechavanne Célia , Briand Valérie , Bouraima Aziz , Guerra José , Choudat Isabelle , Massougbodji Achille , Fayomi Benjamin , Migot-Nabias Florence , Garcia André , Cot Michel
Published: February 2011

The efficiency of malaria prevention during pregnancy was compared between three studies in Benin for malaria infection of the placenta (MIP) and low birth weight (LBW). The first was carried out when chloroquine prophylaxis was still recommended, the second was an intermittent preventive treatment in pregnancy (IPTp) clinical trial comparing sulfadoxine pyrimetamine (SP) versus mefloquine, and the third was an observational study after SP-IPTp national implementation. We showed an association between the use of IPTp and the reduction of LBW (10% with national IPTp and 8.7% in IPTp trial versus 15.7% in pre-trial study). The effect on MIP was better in the trial (2.9% versus 11.2% and 16.7% for national IPTp and pre-trial studies, respectively). In spite of a good overall compliance with the national IPTp (with 84% of women taking at least one dose of SP), there are still failures in adherence to the directly observed therapy (DOT) scheme and needs for better training of health staff.
Human Schistosomiasis Is Associated with Endotoxemia and Toll-Like Receptor 2- and 4-Bearing B Cells
Authors: Onguru Daniel , Liang YanMei , Griffith Qyana , Nikolajczyk Barbara , Mwinzi Pauline , Ganley-Leal Lisa
Published: February 2011

Schistosomiasis is caused by parasitic trematodes. Individuals can accumulate hundreds of intravascular worms, which secrete a myriad of antigenic molecules into the bloodstream. Some of these molecules suppress immunity to microbial Toll-like receptor (TLR) ligands, such as lipopolysaccharides, which may increase host susceptibility to coinfecting pathogens. We show that schistosomiasis is associated with extremely high levels of endotoxemia as well as high mobility group 1, an endogenous inflammatory TLR ligand, in the absence of other coinfected pathogens. Circulating B cells express surface TLR2 and TLR4, reflecting systemic exposure to microbial ligands. Bacterial translocation may occur with schistosomal egg movement from the vascular to the gut and other routes, such as the skin during infection. Our report suggests that immunosuppressive schistosome antigens may have evolved to curb inflammatory responses to the high antigenic burden of translocated bacteria products and endogenous TLR ligands that arise during parasite exposure and inflammation.
Low Doses of Simvastatin Therapy Ameliorate Cardiac Inflammatory Remodeling in Trypanosoma cruzi-Infected Dogs
Authors: Melo Lilian , Caldas Ivo Santana , Azevedo Maíra Araújo , Gonçalves Karolina Ribeiro , da Silva do Nascimento Alvaro Fernando , Figueiredo Vivian Paulino , de Figueiredo Diniz Lívia , de Lima Wanderson Geraldo , Torres Rosália Moraes , Bahia Maria Terezinha , Talvani André
Published: February 2011

Chagas cardiomyopathy remodeling is based on the presence of Trypanosoma cruzi in heart tissue and on the complex inflammatory response leading to a myocardium fibrosis and alterations in conductive and functional heart parameters. This study aims to evaluate Simvastatin on the inflammatory response and heart functionality using dogs infected with Y strain of T. cruzi. Animals were treated daily with Simvastatin (20 mg) for 6 months and submitted to clinical and immunopathological evaluations. Simvastatin reduced heart expression and serum levels of interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) but not interleukin-10 (IL-10), possibly favoring blood parasitism but reducing inflammation and fibrosis in the left ventricle and right atrium. Simvastatin also ameliorated ejection fraction, diastolic diameter, and mass index of the left ventricle 6 months after infection. This study suggests that more investigation should be performed on the use of statins as a prophylactic therapy against cardiac remodeling because of their effects on modifying immune response and benefiting functional parameters in dogs with T. cruzi-induced ventricular dysfunctions.
Isolation and Phylogenetic Analysis of Batai Virus, Germany
Authors: Jöst Hanna , Bialonski Alexandra , Schmetz Christel , Günther Stephan , Becker Norbert , Schmidt-Chanasit Jonas
Published: February 2011

A molecular survey including 16,057 mosquitoes captured in Southwest Germany during the summer of 2009 showed the presence of Batai virus (BATV) in Anopheles maculipennis sensu lato. Until this survey, there was no evidence for circulation of BATV in Germany. Analysis of partial S, M, and L segments showed that the sequences from all three segments were most closely related to BATV, indicating that the virus has not undergone reassortment. Phylogenetic analysis revealed a close relationship of the isolated BATV strain from Germany with strains from Slovakia, Ukraine, and Russia.
Magnetic Resonance Imaging to Assess Blood–Brain Barrier Damage in Murine Trypanosomiasis
Authors: Rodgers Jean , McCabe Christopher , Gettinby George , Bradley Barbara , Condon Barrie , Kennedy Peter G. E.
Published: February 2011

The ability of trypanosomes to invade the brain and induce an inflammatory reaction is well-recognized. This study uses magnetic resonance imaging (MRI) in conjunction with a murine model of central nervous system (CNS) stage trypanosomiasis to investigate this phenomenon at the level of the blood–brain barrier (BBB). Mice were scanned before and after administration of the contrast agent. Signal enhancement maps were generated, and the percentage signal change was calculated. The severity of the neuroinflammation was also assessed. Statistical analysis of the signal change data revealed a significantly (P = 0.028) higher signal enhancement in mice at 28 days post-infection (least squares mean = 26.709) compared with uninfected animals (6.298), indicating the presence of BBB impairment. Leukocytes were found in the meninges and perivascular space of some blood vessels in the infected mice. This study shows that the integrity of the BBB is compromised during CNS stage trypanosomiasis and that the impairment does not correlate with inflammatory cell infiltration.
Economic Impact of Dengue Illness in the Americas
Authors: Shepard Donald S. , Coudeville Laurent , Halasa Yara A. , Zambrano Betzana , Dayan Gustavo H.
Published: February 2011

The growing burden of dengue in endemic countries and outbreaks in previously unaffected countries stress the need to assess the economic impact of this disease. This paper synthesizes existing studies to calculate the economic burden of dengue illness in the Americas from a societal perspective. Major data sources include national case reporting data from 2000 to 2007, prospective cost of illness studies, and analyses quantifying underreporting in national routine surveillance systems. Dengue illness in the Americas was estimated to cost $2.1 billion per year on average (in 2010 US dollars), with a range of $1–4 billion in sensitivity analyses and substantial year to year variation. The results highlight the substantial economic burden from dengue in the Americas. The burden for dengue exceeds that from other viral illnesses, such as human papillomavirus (HPV) or rotavirus. Because this study does not include some components (e.g., vector control), it may still underestimate total economic consequences of dengue.
Evaluation of Nitazoxanide for the Treatment of Disseminated Cystic Echinococcosis: Report of Five Cases and Literature Review
Authors: Pérez-Molina José A. , Díaz-Menéndez Marta , Gallego José I. , Norman Francesca , Monge-Maillo Begoña , Ayala Ana Pérez , López-Vélez Rogelio
Published: February 2011

We aimed to evaluate the effectiveness of nitazoxanide in disseminated cystic echinococcosis (DCE) that failed to respond to surgical and antiparasitic therapy. We report on seven patients (five of them with bony involvement): two cases from the literature and five patients who were included in a compassionate trial of nitazoxanide therapy in our hospital. Median follow-up time until nitazoxanide therapy was 12 years and all patients had received prior medical treatment and extensive surgery. Nitazoxanide (500 mg/12 h) in combination with albendazole, with/without praziquantel, was administered for 3–24 months. Three patients improved: one with muscle involvement (clinico-radiological response), one with lung involvement (radiological response), and another with soft tissue and bony involvement (clinico-radiological response of soft tissue cysts). There was one discontinuation after 15 days of starting therapy. Nitazoxanide combination therapy could have a role in the treatment of DCE when there is no bony involvement. Long-term safety profile seems to be favorable.
Modelling light scattering by mineral dust using spheroids: assessment of applicability
Authors: Merikallio S. , Lindqvist H. , Nousiainen T. , Kahnert M.
Published: February 2011

Abstract. We study the applicability of spheroidal model particles for simulating the single scattering optical properties of mineral dust aerosols. To assess the range of validity of this model, calculations are compared to laboratory observations for five different dust samples at two wavelengths. We further investigate whether the best-fit shape distributions of spheroids for different samples have any similarities that would allow us to suggest a generic first-guess shape distribution for suspended mineral dust. We find that best-fit shape distributions vary considerably between samples and even between wavelengths, making definitive suggestions for a shape distribution difficult. The best-fit shape distribution also depends strongly on the refractive index assumed and the cost function adopted. However, a power-law shape distribution which favours those spheroids that depart most from the spherical shape is found to work well in most cases. To reproduce observed asymmetry parameters, best results are obtained with a power-law distribution with an exponent around three.
Fiber optic distributed temperature sensing for the determination of the nocturnal atmospheric boundary layer height
Authors: Keller C. A. , Huwald H. , Vollmer M. K. , Wenger A. , Hill M. , Parlange M. B. , Reimann S.
Published: February 2011

Abstract. A new method for measuring air temperature profiles in the atmospheric boundary layer at high spatial and temporal resolution is presented. The measurements are based on Raman scattering distributed temperature sensing (DTS) with a fiber optic cable attached to a tethered balloon. These data were used to estimate the height of the stable nocturnal boundary layer. The experiment was successfully deployed during a two-day campaign in September 2009, providing evidence that DTS is well suited for this atmospheric application. Observed stable temperature profiles exhibit an exponential shape confirming similarity concepts of the temperature inversion close to the surface. The atmospheric mixing height (MH) was estimated to vary between 5 m and 50 m as a result of the nocturnal boundary layer evolution. This value is in good agreement with the MH derived from concurrent Radon-222 (222Rn) measurements and in previous studies.
Retrieval of spectral aerosol optical thickness over land using ocean color sensors MERIS and SeaWiFS
Authors: von Hoyningen-Huene W. , Yoon J. , Vountas M. , Istomina L. G. , Rohen G. , Dinter T. , Kokhanovsky A. A. , Burrows J. P.
Published: February 2011

Abstract. For the determination of aerosol optical thickness (AOT) Bremen AErosol Retrieval (BAER) has been developed. Method and main features on the aerosol retrieval are described together with validation and results. The retrieval separates the spectral aerosol reflectance from surface and Rayleigh path reflectance for the shortwave range of the measured spectrum of top-of-atmosphere reflectance for wavelength less than 0.670 μm. The advantage of MERIS (Medium Resolution Imaging Spectrometer on the Environmental Satellite – ENVISAT – of the European Space Agency – ESA) and SeaWiFS (Sea viewing Wide Field Sensor on OrbView-2 spacecraft) observations is the availability of several spectral channels in the blue and visible range enabling the spectral determination of AOT in 7 (or 6) channels (0.412–0.670 μm) and additionally channels in the NIR, which can be used to characterize the surface properties. A dynamical spectral surface reflectance model for different surface types is used to obtain the spectral surface reflectance for this separation. The normalized differential vegetation index (NDVI), taken from the satellite observations, is the model input. Further surface bi-directional reflectance distribution function (BRDF) is considered by the Raman-Pinty-Verstraete (RPV) model. Spectral AOT is obtained from aerosol reflectance using look-up-tables, obtained from radiative transfer calculations with given aerosol phase functions and single scattering albedos either from aerosol models, given by model package "optical properties of aerosol components" (OPAC) or from experimental campaigns. Validations of the obtained AOT retrieval results with data of Aerosol Robotic Network (AERONET) over Europe gave a preference for experimental phase functions derived from almucantar measurements. Finally long-term observations of SeaWiFS have been investigated for 11 year trends in AOT. Western European regions have negative trends with decreasing AOT with time. For the investigated Asian region increasing AOT have been found.
Secular trends in storm-level geomagnetic activity
Authors: Love J. J.
Published: February 2011

Abstract. Analysis is made of K-index data from groups of ground-based geomagnetic observatories in Germany, Britain, and Australia, 1868.0–2009.0, solar cycles 11–23. Methods include nonparametric measures of trends and statistical significance used by the hydrological and climatological research communities. Among the three observatory groups, German K data systematically record the highest disturbance levels, followed by the British and, then, the Australian data. Signals consistently seen in K data from all three observatory groups can be reasonably interpreted as physically meaninginful: (1) geomagnetic activity has generally increased over the past 141 years. However, the detailed secular evolution of geomagnetic activity is not well characterized by either a linear trend nor, even, a monotonic trend. Therefore, simple, phenomenological extrapolations of past trends in solar and geomagnetic activity levels are unlikely to be useful for making quantitative predictions of future trends lasting longer than a solar cycle or so. (2) The well-known tendency for magnetic storms to occur during the declining phase of a sunspot-solar cycles is clearly seen for cycles 14–23; it is not, however, clearly seen for cycles 11–13. Therefore, in addition to an increase in geomagnetic activity, the nature of solar-terrestrial interaction has also apparently changed over the past 141 years.
Evolution of the seasonal temperature cycle in a transient Holocene simulation: orbital forcing and sea-ice
Authors: Fischer N. , Jungclaus J. H.
Published: February 2011

Abstract. Changes in the Earth's orbit lead to changes in the seasonal and meridional distribution of insolation. We quantify the influence of orbitally induced changes on the seasonal temperature cycle in a transient simulation of the last 6000 years – from the mid-Holocene to today – using a coupled atmosphere-ocean general circulation model (ECHAM5/MPI-OM) including a land surface model (JSBACH). The seasonal temperature cycle responds directly to the insolation changes almost everywhere. In the Northern Hemisphere, its amplitude decreases according to an increase in winter insolation and a decrease in summer insolation. In the Southern Hemisphere, the opposite is true. Over the Arctic Ocean, however, decreasing summer insolation leads to an increase of sea-ice cover. The insulating effect of sea ice between the ocean and the atmosphere favors more continental conditions over the Arctic Ocean in winter, resulting in strongly decreasing temperatures. Consequently, there are two competing effects: the direct response to insolation changes and a sea-ice dynamics feedback. The sea-ice feedback is stronger, and thus an increase in the amplitude of the seasonal cycle over the Arctic Ocean occurs. This increase is strongest over the Barents Shelf and influences the temperature response over northern Europe. We compare our modelled seasonal temperatures over Europe to paleo reconstructions. We find better agreements in winter temperatures than in summer temperatures and better agreements in northern Europe than in southern Europe, since the model does not reproduce the southern European Holocene summer cooling inferred from the paleo data. The temperature reconstructions for northern Europe support the notion of the influence of the sea-ice effect on the evolution of the seasonal temperature cycle.
Holocene evolution of summer winds and marine productivity in the tropical Indian Ocean in response to insolation forcing: data-model comparison
Authors: Bassinot F. C. , Marzin C. , Braconnot P. , Marti O. , Mathien-Blard E. , Lombard F. , Bopp L.
Published: February 2011

Abstract. The relative abundance of Globigerinoides bulloides was used to infer Holocene paleo-productivity changes at ODP Site 723 (19°03' N, 57°37' E; Oman Margin) and core MD77-191 (07°30' N, 76°43' E; Southern tip of India). Today, the primary productivity at both sites peaks during the summer season, when monsoon winds result in local Eckman pumping, which brings more nutrients to the surface. On a millennium time-scale, however, the % G.~bulloides records indicate an opposite evolution of paleo-productivity at these sites through the Holocene. The Oman Margin productivity was maximal at ~9 ka (boreal summer insolation maximum) and decreased since then, suggesting a direct response to insolation forcing. On the opposite, the productivity at the southern tip of India was minimum at ~9 ka, and strengthened towards the present. Paleo-reconstructions of wind patterns, marine productivity and foraminifera assemblages were obtained using the IPSL-CM4 climate model coupled to the PISCES marine biogeochemical model and the FORAMCLIM ecophysiological model. These reconstructions are fully coherent with the marine core data. They confirm that the evolution of particulate export production and foraminifera assemblages at our two sites have been directly linked with the strength of the upwelling. Model simulations at 9 ka and 6 ka BP show that the relative evolution between the two sites since the early Holocene can be explained by the weakening but also the southward shift of monsoon winds over the Arabian sea during boreal summer.
The role of phytoplankton dynamics in the seasonal variability of carbon in the subpolar North Atlantic – a modeling study
Authors: Signorini S. R. , Häkkinen S. , Gudmundsson K. , Olsen A. , Omar A. M. , Olafsson J. , Reverdin G. , Henson S. A. , McClain C. R.
Published: February 2011

Abstract. We use an ecosystem/biogeochemical model, which includes multiple phytoplankton functional groups and carbon cycle dynamics, to investigate physical-biological interactions in Icelandic waters. Satellite and in situ data were used to validate the model. The seasonality of the coccolithophore and "other phytoplankton" (diatoms and dinoflagellates) blooms is in general agreement with satellite ocean color products. Nutrient supply, biomass and calcite concentrations are modulated by light and mixed layer depth seasonal cycles. Diatoms are the most abundant with a large bloom in early spring and a secondary bloom in fall. The diatom bloom is followed by blooms of dinoflagellates and coccolithophores. The effect of biological changes on the seasonal variability of the surface ocean pCO2 is nearly twice the temperature effect. The inclusion of multiple functional groups in the model played a major role in the accurate representation of CO2 uptake by biology. For instance, at the peak of the bloom, the exclusion of coccolithophores causes an increase in alkalinity of up to 4 μmol kg−1 with a corresponding increase in DIC of up to 16 μmol kg−1. The net effect of the absence of the coccolithophores bloom is an increase in pCO2 of more than 20 μatm and a reduction of atmospheric CO2 uptake of more than 6 mmol m−2 d−1.
On the fluctuation spectra of seismo-electromagnetic phenomena
Authors: Hayakawa M.
Published: February 2011

Abstract. In order to increase the credibility on the presence of electromagnetic phenomena associated with an earthquake, we have suggested the importance of the modulation (or fluctuation) seen in the time-series data of any seismogenic effects. This paper reviews the fluctuation spectra of seismogenic phenomena in order to indicate the modulation mechanisms in the lithosphere, atmosphere and ionosphere/magnetosphere. Especially, the effect of Earth's tides in the lithosphere and the modulation in the atmosphere (acoustic and atmospheric gravity waves) are discussed and this kind of fluctuation spectra would further provide essential information on the generation mechanisms of different seismogenic effects. Furthermore, the important role of the slope of fluctuation spectra is suggested in order to investigate the self-organized criticality before the lithospheric rupture and its associated effects in different regions such as the ionosphere.
Earthquake forecasting based on data assimilation: sequential Monte Carlo methods for renewal point processes
Authors: Werner M. J. , Ide K. , Sornette D.
Published: February 2011

Abstract. Data assimilation is routinely employed in meteorology, engineering and computer sciences to optimally combine noisy observations with prior model information for obtaining better estimates of a state, and thus better forecasts, than achieved by ignoring data uncertainties. Earthquake forecasting, too, suffers from measurement errors and partial model information and may thus gain significantly from data assimilation. We present perhaps the first fully implementable data assimilation method for earthquake forecasts generated by a point-process model of seismicity. We test the method on a synthetic and pedagogical example of a renewal process observed in noise, which is relevant for the seismic gap hypothesis, models of characteristic earthquakes and recurrence statistics of large quakes inferred from paleoseismic data records. To address the non-Gaussian statistics of earthquakes, we use sequential Monte Carlo methods, a set of flexible simulation-based methods for recursively estimating arbitrary posterior distributions. We perform extensive numerical simulations to demonstrate the feasibility and benefits of forecasting earthquakes based on data assimilation.
Interpreting low normative bone mineral density among Saudi Arabian women
Authors: Greer William , Ahmed Mohammed , Rifai Ayman , Fatton Anne
Published: February 2011

Background: Although results from prior publications have indicated that normative bone mineral density (BMD) in Saudi Arabian women is significantly lower than their North American and European counterparts, there has been no systematic attempt to study these differences across the age-spectrum.

Objectives: To explore these issues in more detail, a new Saudi Arabian normative BMD dataset was systematically derived from patient data at King Faisal Specialist Hospital & Research Centre in Riyadh. Changes in mean BMD were studied with respect to both age and years-since-menopause.

Methods: A retrospective analysis of BMD was carried out among 858 Saudi Arabian women who had undergone routine dual-energy x-ray absorptiometry. In addition to the usual patient details collected at each scan, information from questionnaires summarizing the patient’s medical, lifestyle and menopause history was also used to identify a subset of 179 presumed-normal women.

Results: The normative BMD results for the L2-L4 AP-spine scans agree very closely with published data describing Jeddah women and indicate that during their postmenopausal years, the BMD of an average Saudi Arabian woman drops from a premenopausal plateau (i.e. peak bone mass) of 1.14 g cm−2, to a residual postmenopausal plateau of 0.92 g cm−2. The time-constant for this loss is 4.64 years.

Conclusions: We conclude that the average BMD of normal Saudi Arabian women is approximately 0.1 g cm−2 lower than European women across the entire adult age-range, but that the extent and rate of postmenopausal bone loss appears to lie within the normal European range. This suggests that osteoporosis is first manifested in young adults.
Perceived leadership style of Jordanian academic deans in higher education institutions: Qualitative study
Authors: Al-Omari Aieman Ahmad
Published: February 2011

This qualitative study focuses on the perceptions of two academic deans and their leadership styles. The leadership Behavior Description Questionnaire is used as a frame for analyzing data. Using qualitative methods, observation and interview data were collected. Two themes emerged, Initiating Structure, and Consideration. The Initiating Structure behavior of leaders was all are open to different strategies in problem solving and annual review to make sure faculty/staff members work to capacity. When it came to Consideration, the dominant behavior patterns among deans was having an open door policy with their faculty, willing to make changes, and having high morale within the college.
Trabajadoras domésticas nicaragüenses en Costa Rica: un tortuoso camino hacia el reconocimiento
Authors: Bonnie Alexandra
Published: February 2011

El trabajo doméstico es un sector históricamente vulnerable: se considera a menudo como precario, mal retribuido, inseguro y desprotegido. Los y las trabajadores/as domésticos/as sufren discriminación, aún más cuando son mujeres y extranjeros. El presente artículo pretende estudiar las condiciones laborales de las trabajadoras domésticas en Costa Rica frente a dos importantes evoluciones jurídicas recientes: la reforma del capítulo VIII del Código de Trabajo, relativo al trabajo doméstico remunerado, en 2009, y la entrada en vigor de la nueva Ley General de Migración y Extranjería, en 2010, que afecta a las trabajadoras domésticas migrantes. Como en otros países, las trabajadoras domésticas nacionales y migrantes se organizaron para obtener el reconocimiento de sus derechos laborales, lo que se concretó en el año 2009 con la reforma del Código de Trabajo, considerado como discriminatorio. Esto fue un gran paso para el mejoramiento de su condición, y se destaca el rol importante que tuvo la Asociación de Trabajadoras Domésticas (ASTRADOMES). Sin embargo, la modificación de la normativa no se concreta de igual manera para todas las trabajadoras domésticas. Persisten situaciones de vulnerabilidad y abusos, sobre todo en el caso de las trabajadoras migrantes nicaragüenses. Ello conduce a plantear la necesidad de implementar una política pública integral que atiende a las necesidades de las personas cualquiera sea su nacionalidad y estatus migratorio. El estudio está basado en el análisis de fuentes secundarias tanto académicas como jurídicas. Se complementó la información con entrevistas semiestructuradas a informantes clave, incluyendo a representantes de trabajadoras domésticas.
Mujeres mayas familiares de migrantes: los retos de su rol de apoyo en la construcción de casas de remesas
Authors: Herrara Ruth Piedrasanta
Published: February 2011

A partir del proyecto 'Arquitectura de remesas', auspiciado por la cooperación española y en el cual colaboró la autora de estas líneas, se ha enfocado la transformación en los espacios domésticos en áreas indígenas con altas tasas de expulsión migratoria, donde aparece el papel fundamental que juegan las familias extensas como una insustituible red de apoyo al migrante. Sobre todo se advierte el rol de las mujeres que rodean al hombre que migra (caso más recurrente) y los importantes cambios que se ven impulsadas a realizar al convertirse en las delegadas más confiables en la concreción de los planes y sueños de quienes se han ido. Esto otorga a las mujeres una posición de poder y las enfrenta a retos que deben resolver de una u otra manera (toma de decisiones importantes, administración y gestión de recursos, contacto con la tecnología, etc.). Este artículo comentará estos cambios que pueden ser enfocados como parte de las remesas sociales o como parte de un capital social transferido a las comunidades de origen de los migrantes y que en este caso particular concierne a la capacidad de agencia exigida a las mujeres en este proceso.
DNA Database of the Nicaraguan Population: Allele Frequencies of Importance in Forensic Genetics
Authors: Vargas-Díaz Raquel , Huete-Pérez Jorge A
Published: February 2011

Scientific-technical development in the field of natural science, specifically the discovery of human DNA polymorphism, has allowed us to identify people by their genetic fingerprint, i.e. their DNA, unique to every individual on earth. Its use in criminal investigations and forensic medicine has brought about the creation of DNA databases for discrete groups, populations and entire nations. In Nicaragua, the Molecular Biology Center of the Universidad Centroamericana has been a pioneer in this area of research, providing support for criminal investigations and resolving innumerable cases of paternity disputes. In this report we present the achievements of ten years of research, highlighting the technical aspects and, in particular, the application of the AmpFlSTR Identifiler system, as well as future prospects for scientific investigation in this area.
Design of formulated products: Experimental component
Authors: Conte Elisa , Gani Rafiqul , Cheng Yuen S. , Ng Ka M.
Published: February 2011

A systematic methodology for the design and verification of chemical‐based products is proposed. By integrating modeling, and experiments, the search space is efficiently scanned to identify the feasible product candidates. The product design (or verification) problem consists of three stages: computer‐aided design (Stage 1), which generates a list of feasible candidates, experimental planning (Stage 2), which generates a list of experiments and checks the available experimental set‐ups, and experimental testing (Stage 3), which measures the necessary data and verifies the desirable attributes of the final product. The first stage (Stage 1) has been covered in previous publications, along with detailed case studies. The development of Stage 2 and Stage 3 is considered in this article and highlighted through two case studies involving the design and validation of an insect repellent lotion and a sunscreen lotion. © 2011 American Institute of Chemical Engineers AIChE J, 2012
X‐chromosomal genetic diversity and linkage disequilibrium patterns in Amerindians and non‐Amerindian populations
Authors: Amorim Carlos Eduardo G. , Wang Sijia , Marrero Andrea R. , Salzano Francisco M. , Ruiz‐Linares Andrés , Bortolini Maria Cátira
Published: February 2011

Objectives: We report X‐chromosomal linkage disequilibrium (LD) patterns in Amerindian (Kogi, Wayuu, and Zenu) and admixed Latin American (Central Valley of Costa Rica and Southern Brazilian Gaucho) populations.

Methods: Short tandem repeats (STRs) widespread along the X‐chromosome were investigated in 132 and 124 chromosomes sampled from the Amerindian tribes and the admixed Latin American populations, respectively. Diversity indexes (gene diversity and average numbers of alleles per locus) were estimated for each population and the level of LD was inferred with an exact test.

Results: The Amerindian populations presented lower genetic diversity and a higher proportion of loci in LD than the admixed ones. Two haplotype blocks were identified in the X‐chromosome, both restricted to the Amerindians. The first involved DXS8051 and DXS7108 in Xp22.22 and Xp22.3, while the second found only among the Kogi, included eight loci in a region between Xp11.4 and Xq21.1.

Conclusions: In accordance to previous work done with other populations, human isolates, such as Amerindian tribes, seem to be an optimal choice for the implementation of association studies due to the wide extent of LD which can be found in their gene pool. On the other hand, the low proportion of loci in LD found in both admixed populations studied here could be explained by events related to their history and similarities between the allele frequencies in the parental stocks. Am. J. Hum. Biol., 2011. © 2011 Wiley‐Liss, Inc.
Catalytic properties of transition metal salts immobilized on nanoporous silica polyamine composites II: hydrogenation
Authors: Allen Jesse , Rosenberg Edward , Karakhanov Eduard , Kardashev Sergey V. , Maximov Anton , Zolotukhina Anna
Published: February 2011

The transition metal compounds Pd(OAc)2, RhCl3·4H2O and RuCl3 · nH2O were adsorbed onto the nanoporous silica polyamine composite (SPC) particles (150–250 µm), WP‐1 [poly(ethyleneimine) on amorphous silica], BP‐1 [poly(allylamine) on amorphous silica], WP‐2 (WP‐1 modified with chloroacetic acid) and BP‐2 (BP‐1 modified with chloroacetic acid). Inductively coupled plasma‐atomic emission spectrometry analysis of the dried samples after digestion indicated metal loadings of 0.4–1.2 mmol g−1 except for RhCl3·4H2O on BP‐2 which showed a metal loading of only 0.1 mmol g−1. The metal loaded composites were then screened as hydrogenation catalysts for the reduction of 1‐octene, 1‐decene, 1‐hexene and 1, 3‐cyclohexadiene at a hydrogen pressure of 5 atm in the temperature range of 50–90 °C. All 12 combinations of SPC and transition metal compound proved active for the reduction of the terminal olefins, but isomerization to internal alkenes was competitive in all cases. Under these conditions, selective hydrogenation of 1,3‐cyclohexadiene to cyclohexene was observed with some of the catalysts. Turnover frequencies were estimated for the hydrogenation reactions based on the metal loading and were in some cases comparable to more conventional heterogeneous hydrogenation catalysts. Examination of the catalysts before and after reaction with X‐ray photoelectron spectroscopy and transmission electron microscopy revealed that, in the cases of Pd(OAc)2 on WP‐2, BP‐1 and BP‐2, conversion of the surface‐ligand bound metal ions to metal nano‐particles occurs. This was not the case for Pd(OAc)2 on WP‐1 or for RuCl3 · nH2O and RhCl3· 4H2O on all four composites. The overall results are discussed in terms of differences in metal ion coordination modes for the composite transition‐metal combinations. Suggested ligand interactions are supported by solid state CPMAS 13C NMR analyses and by analogy with previous structural investigations of metal binding modes on these composite materials. Copyright © 2011 John Wiley & Sons, Ltd.
Molecular Logic Gate Arrays
Authors: Prasanna de Silva A.
Published: February 2011

Chemists are now able to emulate the ideas and instruments of mathematics and computer science with molecules. The integration of molecular logic gates into small arrays has been a growth area during the last few years. The design principles underlying a collection of these cases are examined. Some of these computing molecules are applicable in medical‐ and biotechnologies. Cases of blood diagnostics, ‘lab‐on‐a‐molecule’ systems, and molecular computational identification of small objects are included.
HMGB1–Carbenoxolone Interactions: Dynamics Insights from Combined Nuclear Magnetic Resonance and Molecular Dynamics
Authors: Mollica Luca , Morra Giulia , Colombo Giorgio , Musco Giovanna
Published: February 2011

The interplay of protein dynamics and molecular recognition is of fundamental importance in biological processes. Atomic‐resolution insights into these phenomena may provide new opportunities for drug discovery. Herein, we have combined NMR relaxation experiments and residual dipolar coupling (RDC) measurements with molecular dynamics (MD) simulations to study the effects of the anti‐inflammatory drug carbenoxolone (CBNX) on the conformational properties and on the internal dynamics of a subdomain (box A) of high‐mobility group B protein (HMGB1). 15N relaxation data show that CBNX binding enhances the fast pico‐ to nanosecond motions of a loop and partially removes the internal motional anisotropy of the first two helices of box A. Dipolar wave analysis of amide RDC data shows that ligand binding induces helical distortions. In parallel, increased mobility of the loop upon ligand binding is highlighted by the essential dynamics analysis (EDA) of MD simulations. Moreover, simulations detect two possible orientations for CBNX, which induces two possible conformations of helix H3, one being similar to the free form and the second one causing a partial helical distortion. Finally, we introduce a new approach for the analysis of the internal coordination of protein residues that is consistent with experimental data and allows us to pinpoint which substructures of box A are dynamically affected by CBNX. The observations reported here may be useful for understanding the role of protein dynamics in binding at atomic resolution.
Force spectroscopy of chromatin fibers: Extracting energetics and structural information from Monte Carlo simulations
Authors: Kepper Nick , Ettig Ramona , Stehr Rene , Marnach Sven , Wedemann Gero , Rippe Karsten
Published: February 2011

The folding of the nucleosome chain into a chromatin fiber is a central factor for controlling the DNA access of protein factors involved in transcription, DNA replication and repair. Force spectroscopy experiments with chromatin fibers are ideally suited to dissect the interactions that drive this process, and to probe the underlying fiber conformation. However, the interpretation of the experimental data is fraught with difficulties due to the complex interplay of the nucleosome geometry and the different energy terms involved. Here, we apply a Monte Carlo simulation approach to derive virtual chromatin fiber force spectroscopy curves. In the simulations, the effect of the nucleosome geometry, repeat length, nucleosome–nucleosome interaction potential, and the unwrapping of the DNA from the histone protein core on the shape of the force‐extension curves was investigated. These simulations provide a framework for the evaluation of experimental data sets. We demonstrate how the relative contributions of DNA bending and twisting, nucleosome unstacking and unwrapping the nucleosomal DNA from the histone octamer can be dissected for a given fiber geometry. © 2011 Wiley Periodicals, Inc. Biopolymers 95: 435–447, 2011.