bluuebunny/crossref_metadata_2025 huggingface dataset:
Towards Harnessing Phone Messages and Telephone Conversations for Prediction of Food Crisis
Authors: Lukyamuzi Andrew , Ngubiri John , Okori Washington
Published: September 2015

Food insecurity is a global challenge affecting millions of people especially those from least developed regions. Famine predictions are being carried out to estimate when shortage of food is most likely to happen. The traditional data sets such as house hold information, price trends, crop production trends and biophysical data used for predicting food insecurity are both labor intensive and expensive to acquire. Current trends are towards harnessing big data to study various phenomena such sentiment analysis and stock markets. Big data is said to be easier to obtain than traditional datasets. This study shows that phone messages archives and telephone conversations as big datasets are potential for predicting food crisis. This is timely with the current situation of massive penetration of mobile technology and the necessary data can be gathered to foster studies such as this. Computation techniques such as Naïve Bayes, Artificial Networks and Support Vector Machines are prospective candidates in this strategy. If the strategy is to work in a nation like Uganda, areas of concern have been highlighted. Future work points at exploring this approach experimentally.
Extracting Biological Significant Subnetworks from Protein-Protein Interactions Induced by Differentially Expressed Genes of HIV-1 Vpr Variants
Authors: Barman Bandana , Mukhopadhyay Anirban
Published: September 2015

Identification of protein interaction network is very important to find the cell signaling pathway for a particular disease. The authors have found the differentially expressed genes between two sample groups of HIV-1. Samples are wild type HIV-1 Vpr and HIV-1 mutant Vpr. They did statistical t-test and found false discovery rate (FDR) to identify the genes increased in expression (up-regulated) or decreased in expression (down-regulated). In the test, the authors have computed q-values of test to identify minimum FDR which occurs. As a result they found 172 differentially expressed genes between their sample wild type HIV-1 Vpr and HIV-1 mutant Vpr, R80A. They found 68 up-regulated genes and 104 down-regulated genes. From the 172 differentially expressed genes the authors found protein-protein interaction network with string-db and then clustered (subnetworks) the PPI networks with cytoscape3.0. Lastly, the authors studied significance of subnetworks with performing gene ontology and also studied the KEGG pathway of those subnetworks.
Stabilizing and Swinging-Up the Inverted Pendulum Using PI and PID Controllers Based on Reduced Linear Quadratic Regulator Tuned by PSO
Authors: Mousa M. E. , Ebrahim M. A. , Hassan M. A. Moustafa
Published: September 2015

The inherited instabilities in the Inverted Pendulum (IP) system make it one of the most difficult nonlinear problems in the control theory. In this research work, Proportional –Integral and Derivative (PID) Controller with a feed forward gain is used with Reduced Linear Quadratic Regulator (RLQR) for stabilizing the Cart Position and Swinging-up the Pendulum angle. Tuning the Controllers' gains is achieved by using Particle Swarm Optimization (PSO) Technique. Obtaining the combined PID controllers' gains with a feed forward gain and RLQR is a multi-dimensions control problem. The Proposed Controllers give minimum Settling Time, Rise Time, Undershoot and Over shoot for both the Cart Position and the Pendulum angle. A disturbance with different amplitudes is applied to the system, and the results showed the robustness of the systems based on the tuned controllers. The overall results are promising.
Decreased Stress Levels in Nurses: A Benefit of Quiet Time
Authors: Riemer Heather C. , Mates Joanna , Ryan Linda , Schleder Bonnie J.
Published: September 2015

Background

The benefits of quiet time, a therapeutic method of improving the health care environment, have been evaluated in patients, but only a few studies have examined the effects of quiet time on intensive care nurses.

Objective

To evaluate the effects of implementing quiet time in a medical-surgical intensive care unit on levels of light, noise, and nurses’ stress.

Methods

Quiet time consisted of turning down the unit lights for a designated time. Levels of light, noise, and nurses’ stress were measured. Nurses’ stress levels were measured by using a 100-point visual analog scale; unit noise, by using a digital sound level meter (model 407736, Extech Instruments); and unit light, by using an illumination light meter (model 615, Huygen Corporation). Measurements were obtained 30 minutes before and 30 minutes, 1 hour, and 2 hours after implementation of quiet time.

Results

Analysis of variance and comparisons of means indicated that both light levels and nurses’ stress levels were significantly decreased after quiet time (both P < .001). Noise levels were also decreased after quiet time, but the decrease was not significant (P = .08).

Conclusions

Use of quiet time resulted in decreased light levels and decreased stress levels among nurses. Quiet time is an easily performed energy-saving intervention to promote a healthy work environment.
A Young Man With Severe and Disabling Complications of Septic Shock
Authors: Haas L. E. M. , van der Ploeg R. S. , Quak J. J. , Burgmans J. P. J. , Otten M.
Published: September 2015

A young man had severe septic shock with multiorgan failure due to necrotizing fasciitis caused by group A streptococcus after endoscopic repair of a preperitoneal inguinal hernia. He was treated with surgical exploration and antibiotics and resuscitated with fluids, vasopressors, and inotropic agents. He survived this critical illness, but when he woke up from sedation, his vision was lost in both eyes. Ophthalmological evaluation revealed minimal peripapillary retinal hemorrhages without signs of papillary edema. Visually evoked potentials were negative. Magnetic resonance imaging did not show a cause of the visual damage. The patient had bilateral ischemic optic neuropathy diagnosed. Two weeks later, unilateral sudden deafness also developed. The acquired blindness and hearing loss were unchanged after more than 1 year and seem to be permanent, severely disabling this young survivor of septic shock.
IL-12p40 Homodimer Ameliorates Experimental Autoimmune Arthritis
Authors: Lee Seon-Yeong , Jung Young Ok , Kim Doo-Jin , Kang Chang-Min , Moon Young-Mee , Heo Yu-Jung , Oh Hye-Jwa , Park Seong-Jeong , Yang Se-Hwan , Kwok Seung Ki , Ju Ji-Hyeon , Park Sung-Hwan , Sung Young Chul , Kim Ho-Youn , Cho Mi-La
Published: September 2015

IL-23 is the key cytokine that induces the expansion of Th17 cells. It is composed of p19 and p40 subunits of IL-12. The p40 subunit binds competitively to the receptor of IL-23 and blocks its activity. Our aim was to assess the preventive and therapeutic effect of the IL-12p40 homodimer (p40)2 subunit in autoimmune arthritis animal models. In the current study, using IL-1R antagonist–knockout mice and a collagen-induced arthritis model, we investigated the suppressive effect of (p40)2 on inflammatory arthritis. We demonstrated that the recombinant adenovirus-expressing mouse (p40)2 model prevented the development of arthritis when given before the onset of arthritis. It also decreased the arthritis index and joint erosions in the mouse model if transferred after arthritis was established. (p40)2 inhibited the production of inflammatory cytokines and Ag-specific T cell proliferation. It also induced CD4+CD25+Foxp3 regulatory T (Treg) cells in vitro and in vivo, whereas the generation of retinoic acid receptor–related organ receptor γt and Th17 cells was suppressed. The induction of Treg cells and the suppression of Th17 cells were mediated via activated STAT5 and suppressed STAT3. Our data suggest that (p40)2 suppressed inflammatory arthritis successfully. This could be a useful therapeutic approach in autoimmune arthritis to regulate the Th17/Treg balance and IL-23 signaling.
Development and Validation of a Clinical Risk-Assessment Tool Predictive of All-Cause Mortality
Authors: Bello Ghalib A. , Dumancas Gerard G. , Gennings Chris
Published: September 2015

In clinical settings, the diagnosis of medical conditions is often aided by measurement of various serum biomarkers through the use of laboratory tests. These biomarkers provide information about different aspects of a patient's health and overall function of multiple organ systems. We have developed a statistical procedure that condenses the information from a variety of health biomarkers into a composite index, which could be used as a risk score for predicting all-cause mortality. It could also be viewed as a holistic measure of overall physiological health status. This health status metric is computed as a function of standardized values of each biomarker measurement, weighted according to their empirically determined relative strength of association with mortality. The underlying risk model was developed using the biomonitoring and mortality data of a large sample of US residents obtained from the National Health and Nutrition Examination Survey (NHANES) and the National Death Index (NDI). Biomarker concentration levels were standardized using spline-based Cox regression models, and optimization algorithms were used to estimate the weights. The predictive accuracy of the tool was optimized by bootstrap aggregation. We also demonstrate how stacked generalization, a machine learning technique, can be used for further enhancement of the prediction power. The index was shown to be highly predictive of all-cause mortality and long-term outcomes for specific health conditions. It also exhibited a robust association with concurrent chronic conditions, recent hospital utilization, and current health status as assessed by self-rated health.
CoGNaC: A Chaste Plugin for the Multiscale Simulation of Gene Regulatory Networks Driving the Spatial Dynamics of Tissues and Cancer
Authors: Rubinacci Simone , Graudenzi Alex , Caravagna Giulio , Mauri Giancarlo , Osborne James , Pitt-Francis Joe , Antoniotti Marco
Published: September 2015

We introduce a Chaste plugin for the generation and the simulation of Gene Regulatory Networks (GRNs) in multiscale models of multicellular systems. Chaste is a widely used and versatile computational framework for the multiscale modeling and simulation of multicellular biological systems. The plugin, named CoGNaC (Chaste and Gene Networks for Cancer), allows the linking of the regulatory dynamics to key properties of the cell cycle and of the differentiation process in populations of cells, which can subsequently be modeled using different spatial modeling scenarios. The approach of CoGNaC focuses on the emergent dynamical behavior of gene networks, in terms of gene activation patterns characterizing the different cellular phenotypes of real cells and, especially, on the overall robustness to perturbations and biological noise. The integration of this approach within Chaste's modular simulation framework provides a powerful tool to model multicellular systems, possibly allowing for the formulation of novel hypotheses on gene regulation, cell differentiation, and, in particular, cancer emergence and development. In order to demonstrate the usefulness of CoGNaC over a range of modeling paradigms, two example applications are presented. The first of these concerns the characterization of the gene activation patterns of human T-helper cells. The second example is a multiscale simulation of a simplified intestinal crypt, in which, given certain conditions, tumor cells can emerge and colonize the tissue.
Association Between Shigella Infection and Diarrhea Varies Based on Location and Age of Children
Authors: Lindsay Brianna , Saha Debasish , Sanogo Doh , Das Sumon Kumar , Omore Richard , Farag Tamer H. , Nasrin Dilruba , Li Shan , Panchalingam Sandra , Levine Myron M. , Kotloff Karen , Nataro James P. , Magder Laurence , Hungerford Laura , Faruque A. S. G. , Oundo Joseph , Hossain M. Anowar , Adeyemi Mitchell , Stine Oscar Colin
Published: September 2015

Molecular identification of the invasion plasmid antigen-H (ipaH) gene has been established as a useful detection mechanism for Shigella spp. The Global Enteric Multicenter Study (GEMS) identified the etiology and burden of moderate-to-severe diarrhea (MSD) in sub-Saharan Africa and south Asia using a case–control study and traditional culture techniques. Here, we used quantitative polymerase chain reaction (qPCR) to identify Shigella spp. in 2,611 stool specimens from GEMS and compared these results to those using culture. Demographic and nutritional characteristics were assessed as possible risk factors. The qPCR identified more cases of shigellosis than culture; however, the distribution of demographic characteristics was similar by both methods. In regression models adjusting for Shigella quantity, age, and site, children who were exclusively breast-fed had significantly lower odds of MSD compared with children who were not breast-fed (odds ratio [OR] = 0.47, 95% confidence interval (CI) = 0.28–0.81). The association between Shigella quantity and MSD increased with age, with a peak in children of 24–35 months of age (OR = 8.2, 95% CI = 4.3–15.7) and the relationship between Shigella quantity and disease was greatest in Bangladesh (OR = 13.2, 95% CI = 7.3–23.8). This study found that qPCR identified more cases of Shigella and age, site, and breast-feeding status were significant risk factors for MSD.
Global Health Opportunities in Obstetrics and Gynecology Training: Examining Engagement Through an Ethical Lens
Authors: Zaidi Mohammad Y. , Haddad Lisa , Lathrop Eva
Published: September 2015

This study aims to describe global health training (GHT) programs through the ethical lens suggested by the Working Group on Ethics Guidelines for Global Health Training (WEIGHT). A total of 35 GHT programs were identified, and general information was obtained online. Semi-structured telephone interviews of key members of 19 programs were then conducted and transcribed. The interview guide was constructed using WEIGHT recommendations. Transcript data were grouped according to domains: reciprocity, trainee selection and preparedness, needs assessments, and ethical questions. Many programs expressed difficulty in building reciprocal relationships due to imbalanced power structures. Eleven programs reported no formal application process for selecting trainees. Twelve (63%) programs reported only a single day of preparation. Nine (47%) programs did not conduct a formalized needs assessment of partner sites. Ethical considerations varied from concerns for safety to inadequate training for residents. This study reveals the limited preparedness curricula and lack of formalized needs assessments among several programs. Although many programs make an effort to build reciprocal exchanges with host partners, experiences for foreign trainees within the United States are limited, and U.S. residents are often tasked with duties above their training level abroad. This study demonstrates the need to restructure how GHT programs are formed and operated.
Anemia Among Children Exposed to Polyparasitism in Coastal Kenya
Authors: Chang Cojulun Alicia , Bustinduy Amaya L. , Sutherland Laura J. , Mungai Peter L. , Mutuku Francis , Muchiri Eric , Kitron Uriel , King Charles H.
Published: September 2015

Anemia represents a substantial problem for children living in areas with limited resources and significant parasite burden. We performed a cross-sectional study of 254 Kenyan preschool- and early school-age children in a setting endemic for multiple chronic parasitic infections to explore mechanisms of their anemia. Complete venous blood cell counts revealed a high prevalence of local childhood anemia (79%). Evaluating the potential links between low hemoglobin and socioeconomic factors, nutritional status, hemoglobinopathy, and/or parasite infection, we identified age < 9 years (odds ratio [OR]: 12.0, 95% confidence interval [CI]: 4.4, 33) and the presence of asymptomatic malaria infection (OR: 6.8, 95% CI: 2.1, 22) as the strongest independent correlates of having anemia. A total of 130/155 (84%) of anemic children with iron studies had evidence of iron-deficiency anemia (IDA), 16% had non-IDA; 50/52 of additionally tested anemic children met soluble transferrin-receptor (sTfR) criteria for combined anemia of inflammation (AI) with IDA. Children in the youngest age group had the greatest odds of iron deficiency (OR: 10.0, 95% CI: 3.9, 26). Although older children aged 9–11 years had less anemia, they had more detectable malaria, Schistosoma infection, hookworm, and proportionately more non-IDA. Anemia in this setting appears multifactorial such that chronic inflammation and iron deficiency need to be addressed together as part of integrated management of childhood anemia.
National Surveillance of Spotted Fever Group Rickettsioses in the United States, 2008–2012
Authors: Drexler Naomi A. , Dahlgren F. Scott , Heitman Kristen Nichols , Massung Robert F. , Paddock Christopher D. , Behravesh Casey Barton
Published: September 2015

Spotted fever group (SFG) rickettsioses are notifiable conditions in the United States caused by the highly pathogenic Rickettsia rickettsii and less pathogenic rickettsial species such as Rickettsia parkeri and Rickettsia sp. 364D. Surveillance data from 2008 to 2012 for SFG rickettsioses are summarized. Incidence increased from 1.7 cases per million person-years (PY) in 2000 to 14.3 cases per million PY in 2012. During 2008–2012, cases of SFG rickettsiosis were more frequently reported among males, persons of white race, and non-Hispanic ethnicity. Overall, case fatality rate (CFR) was low (0.4%), however, risk of death was significantly higher for American Indian/Alaska Natives (relative risk [RR] = 5.4) and Asian/Pacific Islanders (RR = 5.7) compared with persons of white race. Children aged < 10 years continue to experience the highest CFR (1.6%). Higher incidence of SFG rickettsioses and decreased CFR likely result from increased reporting of tick-borne disease including those caused by less pathogenic species. Recently, fewer cases have been confirmed using species-specific laboratory methods (such as cell culture and DNA detection using polymerase chain reaction [PCR] assays), causing a clouded epidemiological picture. Use of PCR and improved documentation of clinical signs, such as eschars, will better differentiate risk factors, incidence, and clinical outcomes of specific rickettsioses in the future.
A mechanism for biologically induced iodine emissions from sea ice
Authors: Saiz-Lopez A. , Blaszczak-Boxe C. S. , Carpenter L. J.
Published: September 2015

Abstract. Ground- and satellite-based measurements have reported high concentrations of iodine monoxide (IO) in coastal Antarctica. The sources of such a large iodine burden in the coastal Antarctic atmosphere remain unknown. We propose a mechanism for iodine release from sea ice based on the premise that micro-algae are the primary source of iodine emissions in this environment. The emissions are triggered by the biological production of iodide (I−) and hypoiodous acid (HOI) from micro-algae (contained within and underneath sea ice) and their diffusion through sea-ice brine channels, ultimately accumulating in a thin brine layer (BL) on the surface of sea ice. Prior to reaching the BL, the diffusion timescale of iodine within sea ice is depth-dependent. The BL is also a vital component of the proposed mechanism as it enhances the chemical kinetics of iodine-related reactions, which allows for the efficient release of iodine to the polar boundary layer. We suggest that iodine is released to the atmosphere via three possible pathways: (1) emitted from the BL and then transported throughout snow atop sea ice, from where it is released to the atmosphere; (2) released directly from the BL to the atmosphere in regions of sea ice that are not covered with snowpack; or (3) emitted to the atmosphere directly through fractures in the sea-ice pack. To investigate the proposed biology–ice–atmosphere coupling at coastal Antarctica we use a multiphase model that incorporates the transport of iodine species, via diffusion, at variable depths, within brine channels of sea ice. Model simulations were conducted to interpret observations of elevated springtime IO in the coastal Antarctic, around the Weddell Sea. While a lack of experimental and observational data adds uncertainty to the model predictions, the results nevertheless show that the levels of inorganic iodine (i.e. I2, IBr, ICl) released from sea ice through this mechanism could account for the observed IO concentrations during this timeframe. The model results also indicate that iodine may trigger the catalytic release of bromine from sea ice through phase equilibration of IBr. Considering the extent of sea ice around the Antarctic continent, we suggest that the resulting high levels of iodine may have widespread impacts on catalytic ozone destruction and aerosol formation in the Antarctic lower troposphere.
Comparing the CarbonTracker and TM5-4DVar data assimilation systems for CO2 surface flux inversions
Authors: Babenhauserheide A. , Basu S. , Houweling S. , Peters W. , Butz A.
Published: September 2015

Abstract. Data assimilation systems allow for estimating surface fluxes of greenhouse gases from atmospheric concentration measurements. Good knowledge about fluxes is essential to understand how climate change affects ecosystems and to characterize feedback mechanisms. Based on the assimilation of more than 1 year of atmospheric in situ concentration measurements, we compare the performance of two established data assimilation models, CarbonTracker and TM5-4DVar (Transport Model 5 – Four-Dimensional Variational model), for CO2 flux estimation. CarbonTracker uses an ensemble Kalman filter method to optimize fluxes on ecoregions. TM5-4DVar employs a 4-D variational method and optimizes fluxes on a 6° × 4° longitude–latitude grid. Harmonizing the input data allows for analyzing the strengths and weaknesses of the two approaches by direct comparison of the modeled concentrations and the estimated fluxes. We further assess the sensitivity of the two approaches to the density of observations and operational parameters such as the length of the assimilation time window. Our results show that both models provide optimized CO2 concentration fields of similar quality. In Antarctica CarbonTracker underestimates the wintertime CO2 concentrations, since its 5-week assimilation window does not allow for adjusting the distant surface fluxes in response to the detected concentration mismatch. Flux estimates by CarbonTracker and TM5-4DVar are consistent and robust for regions with good observation coverage, regions with low observation coverage reveal significant differences. In South America, the fluxes estimated by TM5-4DVar suffer from limited representativeness of the few observations. For the North American continent, mimicking the historical increase of the measurement network density shows improving agreement between CarbonTracker and TM5-4DVar flux estimates for increasing observation density.
Evaluating BC and NOx emission inventories for the Paris region from MEGAPOLI aircraft measurements
Authors: Petetin H. , Beekmann M. , Colomb A. , Denier van der Gon H. A. C. , Dupont J.-C. , Honoré C. , Michoud V. , Morille Y. , Perrussel O. , Schwarzenboeck A. , Sciare J. , Wiedensohler A. , Zhang Q. J.
Published: September 2015

Abstract. High uncertainties affect black carbon (BC) emissions, and, despite its important impact on air pollution and climate, very few BC emissions evaluations are found in the literature. This paper presents a novel approach, based on airborne measurements across the Paris, France, plume, developed in order to evaluate BC and NOx emissions at the scale of a whole agglomeration. The methodology consists in integrating, for each transect, across the plume observed and simulated concentrations above background. This allows for several error sources (e.g., representativeness, chemistry, plume lateral dispersion) to be minimized in the model used. The procedure is applied with the CHIMERE chemistry-transport model to three inventories – the EMEP inventory and the so-called TNO and TNO-MP inventories – over the month of July 2009. Various systematic uncertainty sources both in the model (e.g., boundary layer height, vertical mixing, deposition) and in observations (e.g., BC nature) are discussed and quantified, notably through sensitivity tests. Large uncertainty values are determined in our results, which limits the usefulness of the method to rather strongly erroneous emission inventories. A statistically significant (but moderate) overestimation is obtained for the TNO BC emissions and the EMEP and TNO-MP NOx emissions, as well as for the BC / NOx emission ratio in TNO-MP. The benefit of the airborne approach is discussed through a comparison with the BC / NOx ratio at a ground site in Paris, which additionally suggests a spatially heterogeneous error in BC emissions over the agglomeration.
Long-lived atmospheric trace gases measurements in flask samples from three stations in India
Authors: Lin X. , Indira N. K. , Ramonet M. , Delmotte M. , Ciais P. , Bhatt B. C. , Reddy M. V. , Angchuk D. , Balakrishnan S. , Jorphail S. , Dorjai T. , Mahey T. T. , Patnaik S. , Begum M. , Brenninkmeijer C. , Durairaj S. , Kirubagaran R. , Schmidt M. , Swathi P. S. , Vinithkumar N. V. , Yver Kwok C. , Gaur V. K.
Published: September 2015

Abstract. With the rapid growth in population and economic development, emissions of greenhouse gases (GHGs) from the Indian subcontinent have sharply increased during recent decades. However, evaluation of regional fluxes of GHGs and characterization of their spatial and temporal variations by atmospheric inversions remain uncertain due to a sparse regional atmospheric observation network. As a result of an Indo-French collaboration, three new atmospheric stations were established in India at Hanle (HLE), Pondicherry (PON) and Port Blair (PBL), with the objective of monitoring the atmospheric concentrations of GHGs and other trace gases. Here we present the results of the measurements of CO2, CH4, N2O, SF6, CO, and H2 from regular flask sampling at these three stations over the period 2007–2011. For each species, annual means, seasonal cycles and gradients between stations were calculated and related to variations in natural GHG fluxes, anthropogenic emissions, and monsoon circulations. Covariances between species at the synoptic scale were analyzed to investigate the likely source(s) of emissions. The flask measurements of various trace gases at the three stations have the potential to constrain the inversions of fluxes over southern and northeastern India. However, this network of ground stations needs further extension to other parts of India to better constrain the GHG budgets at regional and continental scales.
Isotopic signatures of production and uptake of H2 by soil
Authors: Chen Q. , Popa M. E. , Batenburg A. M. , Röckmann T.
Published: September 2015

Abstract. Molecular hydrogen (H2) is the second most abundant reduced trace gas (after methane) in the atmosphere, but its biogeochemical cycle is not well understood. Our study focuses on the soil production and uptake of H2 and the associated isotope effects. Air samples from a grass field and a forest site in the Netherlands were collected using soil chambers. The results show that uptake and emission of H2 occurred simultaneously at all sampling sites, with strongest emission at the grassland sites where clover (N2 fixing legume) was present. The H2 mole fraction and deuterium content were measured in the laboratory to determine the isotopic fractionation factor during H2 soil uptake (αsoil) and the isotopic signature of H2 that is simultaneously emitted from the soil (δDsoil). By considering all net-uptake experiments, an overall fractionation factor for deposition of αsoil = kHD/kHH = 0.945 ± 0.004 (95 % CI) was obtained. The difference in mean αsoil between the forest soil 0.937 ± 0.008 and the grassland 0.951 ± 0.025 is not statistically significant. For two experiments, the removal of soil cover increased the deposition velocity (vd) and αsoil simultaneously, but a general positive correlation between vd and αsoil was not found in this study. When the data are evaluated with a model of simultaneous production and uptake, the isotopic composition of H2 that is emitted at the grassland site is calculated as δDsoil = (−530 ± 40) ‰. This is less deuterium-depleted than what is expected from isotope equilibrium between H2O and H2.
Preliminary validation of refractivity from a new radio occultation sounder GNOS/FY-3C
Authors: Liao M. , Zhang P. , Yang G. L. , Bi Y. M. , Liu Y. , Bai W. H. , Meng X. G. , Du Q. F. , Sun Y. Q.
Published: September 2015

Abstract. As a new member of space-based radio occultation sounder, the GNOS (Global Navigation Satellite System Occultation Sounder) mounted on FY-3C has been carrying out the atmospheric sounding since 23 September 2013. GNOS takes a daily measurement up to 800 times with GPS (Global Position System) and Chinese BDS (BeiDou navigation satellite) signals. The refractivity profiles from GNOS are compared with the co-located ECMWF (European Centre for Medium-Range Weather Forecasts) analyses in this paper. Bias and standard deviation have being calculated as the function of altitude. The mean bias is about 0.2 % from the near surface to 35 km. The average standard deviation is within 2 % while it is down to about 1 % in the range 5–30 km where best soundings are usually made. To evaluate the performance of GNOS, COSMIC (Constellation Observing System for Meteorology, Ionosphere and Climate) and GRAS/METOP-A (GNSS Receiver for Atmospheric Sounding) data are also compared to ECMWF analyses as the reference. The results show that GNOS/FY-3C meets the requirements of the design well. It possesses a sounding capability similar to COSMIC and GRAS in the vertical range of 0–30 km, though it needs improvement in higher altitude. Generally, it provides a new data source for global NWP (numerical weather prediction) community.
Complexity of diatom response to Lateglacial and Holocene climate and environmental change in ancient, deep, and oligotrophic Lake Ohrid (Macedonia/Albania)
Authors: Zhang X. S. , Reed J. M. , Lacey J. H. , Francke A. , Leng M. J. , Levkov Z. , Wagner B.
Published: September 2015

Abstract. Lake Ohrid (Macedonia/Albania) is a rare example of a deep, ancient Mediterranean lake and is a key site for palaeoclimate research in the northeastern Mediterranean region. This study conducts the first high-resolution diatom analysis during the Lateglacial and Holocene in Lake Ohrid. It demonstrates a complex diatom response to temperature change, with a direct response to temperature-induced productivity and an indirect response to temperature-related stratification/mixing regime and epilimnetic nutrient availability. During the Lateglacial (ca. 12 300–11 800 cal yr BP), the low-diversity dominance of hypolimnetic Cyclotella fottii indicates low temperature-dependent lake productivity. During the earliest Holocene (ca. 11 800–10 600 cal yr BP), although the slight increase in small, epilimnetic C. minuscula suggests climate warming and enhanced thermal stratification, diatom concentration remains very low as during the Lateglacial, indicating that temperature increase was muted. The early Holocene (ca. 10 600–8200 cal yr BP) marked a sustained increase in epilimnetic taxa, with mesotrophic C. ocellata indicating high temperature-induced lake productivity between ca. 10 600–10 200 cal yr BP and between ca. 9500–8200 cal yr BP, and with C. minuscula in response to low nutrient availability in the epilimnion between ca. 10 200–9500 cal yr BP. During the mid Holocene (ca. 8200–2600 cal yr BP), when sedimentological and geochemical proxies provide evidence for high temperature, anomalously low C. ocellata abundance is probably a response to epilimnetic nutrient limitation, almost mimicking the Lateglacial flora apart from mesotrophic Stephanodiscus transylvanicus indicative of high temperature-induced productivity in the hypolimnion. During the late Holocene (ca. 2600–0 cal yr BP), high abundance and fluctuating composition of epilimnetic taxa is largely a response to enhanced anthropogenic nutrient input. In this deep, oligotrophic lake, this study demonstrates the strong influence of lake physical and chemical processes in mediating the complex response of diatoms to climate change with particular respect to temperature.
Influence of measurement uncertainties on soluble aerosol iron over the oceans
Authors: Meskhidze N. , Johnson M. S. , Hurley D. , Dawson K.
Published: September 2015

Abstract. The atmospheric supply of dust iron (Fe) plays a crucial role in the Earth's biogeochemical cycle and is of specific importance as a micronutrient in the marine environment. Observations show several orders of magnitude variability in the fractional solubility of Fe in dust aerosols, making it hard to assess the role of mineral dust for global ocean biogeochemical Fe cycle. In this study we compare the operational solubility of dust aerosol Fe associated with one of the flow-through leaching protocols to the results of the global 3-D chemical transport model GEOS-Chem. In the protocol aerosol Fe is defined soluble by first deionized water leaching of mineral dust through a 0.45 μm pore size membrane followed by acidification and storage of the leachate over a long period of time prior to the analysis. To assess the concentrations of soluble Fe inferred by this flow-through leaching protocol we are using in situ measurements of dust size distribution with the prescribed of 50 % fractional solubility of Fe in less than 0.45 μm sized dust particles collected in the leachate. In the model, the fractional solubility of Fe is either explicitly calculated using complex dust Fe dissolution module, or prescribed to be 1 and 4 %. Calculations show that the fractional solubility of Fe derived through the flow-through leaching is typically higher compared to the model results. The largest differences (>30 %) are predicted to occur farther away from the dust source regions, over the areas where sub-0.45 μm sized mineral dust particles contribute a larger fraction of the total dust mass. This study suggests that inconsistences in the operational definition of soluble Fe could contribute to the wide range of the fractional solubility of dust aerosol Fe reported in the literature.
Climatology of Vb cyclones, physical mechanisms and their impact on extreme precipitation over Central Europe
Authors: Messmer M. , Gómez-Navarro J. J. , Raible C. C.
Published: September 2015

Abstract. Cyclones, which develop over the western Mediterranean and move northeastward are a major source of extreme weather and known to be responsible for heavy precipitation over the northern side of the Alpine range and Central Europe. As the relevant processes triggering these so-called Vb events and their impact on extreme precipitation are not yet fully understood, this study focuses on gaining insight into the dynamics of past events. For this, a cyclone detection and tracking tool is applied to the ERA-Interim reanalysis (1979–2013) to identify prominent Vb situations. Precipitation in the ERA-Interim and the E-OBS data sets is used to evaluate case-to-case precipitation amounts and to assess consistency between the two data sets. Both data sets exhibit high variability in precipitation amounts among different Vb events. While only 23 % of all Vb events are associated with extreme precipitation, around 15 % of all extreme precipitation days (99 percentile) over the northern Alpine region and Central Europe are induced by Vb events, although Vb cyclones are rare events (2.3 per year). To obtain a better understanding of the variability within Vb events, the analysis of the 10 heaviest and lowest precipitation Vb events reveals noticeable differences in the state of the atmosphere. These differences are most pronounced in the geopotential height and potential vorticity field, indicating a much stronger cyclone for heavy precipitation events. The related differences in wind direction are responsible for the moisture transport around the Alps and the orographical lifting along the northern slopes of the Alps. These effects are the main reasons for a disastrous outcome of Vb events, and consequently are absent in the Vb events associated with low precipitation. Hence, our results point out that heavy precipitation related to Vb events is mainly related to large-scale dynamics rather than to thermodynamic processes.
Short Communication: Evidence for non-Gaussian distribution of rock weathering rates
Authors: Emmanuel S.
Published: September 2015

Abstract. The weathering of rocks influences the geochemistry of the oceans, the erosion of landscapes and man-made structures, and even the global climate. Although a high degree of variance is often observed in rate measurements, little is understood about the statistical characteristics of weathering rate distributions. This preliminary study demonstrates that the weathering rates of limestone, determined from measurements of an ancient eroded limestone edifice, can exhibit highly non-Gaussian behavior. While a Gaussian model produced a poor fit with the data, an alternative model – the generalized extreme value (GEV) framework – was capable of capturing the asymmetric long-tailed distribution, in good agreement with the measured curve. Furthermore, the non-Gaussian distribution of these field rates was found to have similar characteristics to the distribution of rates measured over much smaller microscopic regions of limestone surfaces in laboratory experiments. Such similar behavior could be indicative of analogous chemical and mechanical weathering processes acting over a range of spatial and temporal scales. Moreover, highly asymmetric rate distributions with high variance could be characteristic of rates not only in carbonate rocks, but also in other rock types, suggesting that the use of a small number of measurements to determine field weathering rates may be insufficient to fully characterize the range of rates in natural systems.
Landscapes of memory: a practice theory approach to geographies of memory
Authors: Maus G.
Published: September 2015

Abstract. Conceptualised from a practice theory perspective, "landscape" can be employed as an overarching term encompassing otherwise divergent perspectives within geographies of memory: landscape of memory can denote social practice, meaningful materiality, individual experience, and collective imaginations as constituent of localised memory. Using Theodore Schatzki's practice theory, landscapes of memory are described as a social phenomenon: practices of memory contextualise certain places as meaningful in relation to the past. In turning to small Cold War munitions bunkers, by way of example, it is demonstrated how this perspective broadens the scope of geographies of memory to include everyday practices and their relation to collective memories.
Stream temperature prediction in ungauged basins: review of recent approaches and description of a new physics-derived statistical model
Authors: Gallice A. , Schaefli B. , Lehning M. , Parlange M. B. , Huwald H.
Published: September 2015

Abstract. The development of stream temperature regression models at regional scales has regained some popularity over the past years. These models are used to predict stream temperature in ungauged catchments to assess the impact of human activities or climate change on riverine fauna over large spatial areas. A comprehensive literature review presented in this study shows that the temperature metrics predicted by the majority of models correspond to yearly aggregates, such as the popular annual maximum weekly mean temperature (MWMT). As a consequence, current models are often unable to predict the annual cycle of stream temperature, nor can the majority of them forecast the inter-annual variation of stream temperature. This study presents a new statistical model to estimate the monthly mean stream temperature of ungauged rivers over multiple years in an Alpine country (Switzerland). Contrary to similar models developed to date, which are mostly based on standard regression approaches, this one attempts to incorporate physical aspects into its structure. It is based on the analytical solution to a simplified version of the energy-balance equation over an entire stream network. Some terms of this solution cannot be readily evaluated at the regional scale due to the lack of appropriate data, and are therefore approximated using classical statistical techniques. This physics-inspired approach presents some advantages: (1) the main model structure is directly obtained from first principles, (2) the spatial extent over which the predictor variables are averaged naturally arises during model development, and (3) most of the regression coefficients can be interpreted from a physical point of view – their values can therefore be constrained to remain within plausible bounds. The evaluation of the model over a new freely available data set shows that the monthly mean stream temperature curve can be reproduced with a root-mean-square error (RMSE) of ±1.3 °C, which is similar in precision to the predictions obtained with a multi-linear regression model. We illustrate through a simple example how the physical aspects contained in the model structure can be used to gain more insight into the stream temperature dynamics at regional scales.
A parsimonious analytical model for simulating multispecies plume migration
Authors: Chen J.-S. , Liang C.-P. , Liu C.-W. , Li L. Y.
Published: September 2015

Abstract. A parsimonious analytical model for rapidly predicting the long-term plume behavior of decaying contaminant such as radionuclide and dissolved chlorinated solvent is presented in this study. Generalized analytical solutions in compact format are derived for the two-dimensional advection-dispersion equations coupled with sequential first-order decay reactions involving an arbitrary number of species in groundwater system. The solution techniques involve the sequential applications of the Laplace, finite Fourier cosine, and generalized integral transforms to reduce the coupled partial differential equation system to a set of linear algebraic equations. The system of algebraic equations is next solved for each species in the transformed domain, and the solutions in the original domain are then obtained through consecutive integral transform inversions. Explicit form solutions for a special case are derived using the generalized analytical solutions and are verified against the numerical solutions. The analytical results indicate that the parsimonious analytical solutions are robust and accurate. The solutions are useful for serving as simulation or screening tools for assessing plume behaviors of decaying contaminants including the radionuclides and dissolved chlorinated solvents in groundwater systems.
Linking catchment-scale subglacial discharge to subsurface glacially modified waters near the front of a marine terminating outlet glacier using an autonomous underwater vehicle
Authors: Stevens L. A. , Straneo F. , Das S. B. , Plueddemann A. J. , Kukulya A. L. , Morlighem M.
Published: September 2015

Abstract. Measurements of near-ice (< 200 m) hydrography and near-terminus subglacial hydrology are lacking due in large part to the difficulty in working at the margin of calving glaciers. Here we pair detailed hydrographic and bathymetric measurements collected with an Autonomous Underwater Vehicle as close as 150 m from the ice/ocean interface of the Sarqardliup sermia/Sarqardleq Fjord system, West Greenland, with modeled and observed subglacial discharge locations and magnitudes. We find evidence of two main types of subsurface glacially modified water localized in space and with distinct properties that are consistent with runoff discharged at two locations along the grounded margin. These locations, in turn, correspond with two prominent subglacial subcatchments beneath Sarqardliup sermia. Thus, near-ice observations and subglacial discharge routing indicate that subglacial discharge from this glacier occurs at only two primary locations and gives rise to two distinct glacially modified waters. Furthermore, we show that the location with the largest discharge flux is associated with the lighter, fresher glacially modified watermass. This is qualitatively consistent with results from an idealized plume model.
Hof van Justitie oordeelt over mandaat van ECB inzake monetair beleid
Authors: Louisse M.L.
Published: September 2015

Hof van Justitie oordeelt over mandaat van ECB inzake monetair beleid

Op 16 juni 2015 heeft het Hof van Justitie van de Europese Unie prejudiciële vragen beantwoord van het Bundesverfassungsgericht over de verenigbaarheid van het Outright Monetary Transactions-programma (OMT-programma) met het Europese recht, en meer in het bijzonder met het mandaat van de Europese Centrale Bank (ECB). Dit OMT-programma is vergelijkbaar met het programma van kwantitatieve verruiming (QE), waarmee de ECB in maart 2015 is gestart. Dit artikel gaat in op het arrest van het Hof van Justitie, de mogelijke aanknopingspunten die dit arrest biedt voor de beantwoording van de vraag of de ECB met het QE-programma binnen haar mandaat blijft, en de mogelijke gevolgen die dit arrest heeft voor de onafhankelijkheid van de ECB.
De reikwijdte van de zorgplicht binnen concernverhoudingen
Authors: van Liere F.
Published: September 2015

De reikwijdte van de zorgplicht binnen concernverhoudingen

In deze bijdrage wordt ingegaan op de aansprakelijkheid van de moedermaatschappij jegens crediteuren van haar dochter(s) vanwege schending van de zorgplicht om de crediteurenbelangen in acht te nemen. De term zorgplicht is in lagere rechtspraak en literatuur ontwikkeld, maar de Hoge Raad heeft deze term nog niet aanvaard, waardoor nog altijd onduidelijkheid bestaat over de exacte invulling van de zorgplicht. In dat kader worden drie vragen behandeld: naar de inhoud van de zorgplicht, naar de omstandigheden waaronder zij zich manifesteert en naar het moment van inwerkingtreding van de zorgplicht. Aan de hand van de kernarresten en de economische werkelijkheid worden deze vragen beantwoord en wordt geconcludeerd dat sprake is van een immer aanwezige zorgplicht om de belangen van de crediteuren in acht te nemen als uitwerking van de concernleidingsplicht van de moedermaatschappij binnen concernverhoudingen.
Identity Management: Lightweight SAML for Less Processing Power
Authors:   Faculty of Computers and Information, Cairo University, Egypt, Ali Mohammed , Sobh Tarek S. , El-Gamal Salwa
Published: September 2015

Identity management has emerged as important issue for reducing complexity and improving user experience when accessing services. In addition to, recently authentication services added SAML to the range of authentication options to be available to cloud subscriber. This work mainly focused on SAML representation in the existing identity management frameworks and its suitability. We introduced a new representation of SAML that makes it light in weight and easier in parsing and dealing with. This representation is demonstrated using JSON. In our new SAML representation, we enhanced the performance of marshalling the SAML by 28.99%. In this paper, we will go into these challenges to introduce a new representation for the identity and access management markup language. Our proposed representation is designed to match the small processing power devices for faster generation, parsing and communication.