bluuebunny/crossref_metadata_2025 huggingface dataset:
Design Ontology Based on Geometry APIs and Its Application
Authors: Wang Jihua , Wang Huayu
Published: July 2013

Design ontology is playing important roles in collaborative and knowledge-intensive design. The ontology based on geometry APIs and surface-behaviors was proposed to build the semantic connection among functions, behaviors and structures, which further refine product design FBS models. The lightweight network transmission and the rapid product design can be finished by the design ontology. The cases proved that the representation of design knowledge based on geometry API ontology can be easier to share and access.
Effect of Inertia Weight w on PSO-SA Algorithm
Authors: Wang Shigang , Zhou Fangfang , Wang Fengjuan
Published: July 2013

Since particle swarm algorithm was proposed, because of its easy to understand and implement, the algorithm has been rapid development. However, the algorithm is easy to convergence, and the simulated annealing algorithm has strong local search ability, which can make the search process to avoid falling into local optimal solution. Because of the complementary of the advantages and disadvantages of the two algorithms, a new PSO-SA algorithm appears. This paper focuses on researching the effect of inertia weight of PSO-SA algorithm on the performance of the algorithm. PSO-SA algorithm is applied in solving the shortest path on curved surface, through an example to illustrate function of the inertia weight in algorithm.
IL-22 Regulates Iron Availability In Vivo through the Induction of Hepcidin
Authors: Smith Carole L. , Arvedson Tara L. , Cooke Keegan S. , Dickmann Leslie J. , Forte Carla , Li Hongyan , Merriam Kimberly L. , Perry V. Kristina , Tran Linh , Rottman James B. , Maxwell Joseph R.
Published: July 2013

Iron is a trace element important for the proper folding and function of various proteins. Physiological regulation of iron stores is of critical importance for RBC production and antimicrobial defense. Hepcidin is a key regulator of iron levels within the body. Under conditions of iron deficiency, hepcidin expression is reduced to promote increased iron uptake from the diet and release from cells, whereas during conditions of iron excess, induction of hepcidin restricts iron uptake and movement within the body. The cytokine IL-6 is well established as an important inducer of hepcidin. The presence of this cytokine during inflammatory states can induce hepcidin production, iron deficiency, and anemia. In this study, we show that IL-22 also influences hepcidin production in vivo. Injection of mice with exogenous mouse IgG1 Fc fused to the N terminus of mouse IL-22 (Fc–IL-22), an IL-22R agonist with prolonged and enhanced functional potency, induced hepcidin production, with a subsequent decrease in circulating serum iron and hemoglobin levels and a concomitant increase in iron accumulation within the spleen. This response was independent of IL-6 and was attenuated in the absence of the IL-22R–associated signaling kinase, Tyk2. Ab-mediated blockade of hepcidin partially reversed the effects on iron biology caused by IL-22R stimulation. Taken together, these data suggest that exogenous IL-22 regulates hepcidin production to physiologically influence iron usage.
A Critical Context-Dependent Role for E Boxes in the Targeting of Somatic Hypermutation
Authors: McDonald Jessica J. , Alinikula Jukka , Buerstedde Jean-Marie , Schatz David G.
Published: July 2013

Secondary B cell repertoire diversification occurs by somatic hypermutation (SHM) in germinal centers following Ag stimulation. In SHM, activation-induced cytidine deaminase mutates the V region of the Ig genes to increase the affinity of Abs. Although SHM acts primarily at Ig loci, low levels of off-target mutation can result in oncogenic DNA damage, illustrating the importance of understanding SHM targeting mechanisms. A candidate targeting motif is the E box, a short DNA sequence (CANNTG) found abundantly in the genome and in many SHM target genes. Using a reporter assay in chicken DT40 B cells, we previously identified a 1928-bp portion of the chicken IgL locus capable of supporting robust SHM. In this article, we demonstrate that mutation of all 20 E boxes in this fragment reduces SHM targeting activity by 90%, and that mutation of subsets of E boxes reveals a functional hierarchy in which E boxes within “core” targeting regions are of greatest importance. Strikingly, when the sequence and spacing of the 20 E boxes are preserved but surrounding sequences are altered, SHM targeting activity is eliminated. Hence, although E boxes are vital SHM targeting elements, their function is completely dependent on their surrounding sequence context. These results suggest an intimate cooperation between E boxes and other sequence motifs in SHM targeting to Ig loci and perhaps also in restricting mistargeting to certain non-Ig loci.
Supplier relationship management – anathema for the South African public procurement sector
Authors: Naude Micheline J. , Ambe Intaher M. , Kling René
Published: July 2013

The public sector is recognised as being one of the most important customer groups for many suppliers and service providers because of the volume of public expenditure. Supplier relationship management (SRM) is a necessary tool on which businesses in the public and private sectors rely. However, in the South African public sector, despite the intention to boost service delivery through efficient and effective supplier-management processes, the development of sound supplier relationships is a challenge. The purpose of this article is to provide insight into supplier-relationship challenges and to suggest a framework for implementing SRM in the South African public sector. The research presented is based on a survey using both descriptive and exploratory research. Data were gathered through semi-structured interviews with 15 participants at eight institutions in KwaZulu-Natal. Purposive sampling techniques were used. The findings reveal that the main supplier-related challenges that handicap procurement practices in the province are a lack of experience, a lack of affirmable suppliers, threats and bribes, a lack of integrity, an inability to meet delivery deadlines and quality issues. The findings further reveal that supplier relationships in the public sector are of a transactional nature. A five-stage framework is therefore recommended for implementing SRM in the South African public sector and in order to assist government procurement officials to reap the benefits of SRM whilst supporting the requirements of public-sector procurement.
Correlation of Ultrasonographic Parameters with Serum Creatinine in Chronic Kidney Disease
Authors: Siddappa Jagdeesh K. , Singla Saurabh , Al Ameen Mohammed , Rakshith S.C. , Kumar Naveen
Published: July 2013

Objective:

The purpose of our study is to correlate renal echogenicity with serum creatinine in order to determine the significance of renal echogenicity when it comes to identifying the progression of chronic kidney disease (CKD) and for the sonographic grading of CKD.

Materials and Methods:

Sixty patients above 30 years of age who had been diagnosed with CKD according to the guidelines of the National Kidney Foundation were included in the study. Patients on kidney replacement therapy or with fatty liver findings on ultrasonography were excluded. Ultrasounds of kidneys were performed by two radiologists who were blind to the patients’ serum creatinine levels. Renal cortical echogenicity was compared with serum creatinine. Statistical analysis was performed using one-way ANOVA followed by Scheffe's test. The relationship between serum creatinine and sonographic features was assessed by correlation coefficient analysis. APvalue less than 0.05 was considered statistically significant.

Results:

Mean serum creatinine was 2.80 mg/dl for Grade 1 (range: 0.9-9.2 mg/dl), 3.69 mg/dl for Grade 2 (range: 1.2-10.3 mg/dl), 3.86 mg/dl for Grade 3 (range: 1.1-6.5 mg/dl), and 7.90 mg/dl for Grade 4 (range: 3.1-11.4 mg/dl). The grades being determined by cortical echogenicity on imaging A statistically significant, positive correlation was observed between serum creatinine and grading based on cortical echogenicity (P= 0.004).

Conclusion:

Renal echogenicity and its grading correlates better with serum creatinine in CKD than other sonographic parameters such as longitudinal size, parenchymal thickness, and cortical thickness. Hence, renal echogenicity is a better parameter than serum creatinine for estimating renal function in CKD, and has the added advantage of irreversibility.
Quality of Piped and Stored Water in Households with Children Under Five Years of Age Enrolled in the Mali Site of the Global Enteric Multi-Center Study (GEMS)
Authors: Baker Kelly K. , Sow Samba O. , Kotloff Karen L. , Nataro James P. , Farag Tamer H. , Tamboura Boubou , Doumbia Mama , Sanogo Doh , Diarra Drissa , O'Reilly Ciara E. , Mintz Eric , Panchalingam Sandra , Wu Yukun , Blackwelder William C. , Levine Myron M.
Published: July 2013

Water, sanitation, and hygiene information was collected during a matched case-control study of moderate and severe diarrhea (MSD) among 4,096 children < 5 years of age in Bamako, Mali. Primary use of piped water (conditional odds ratio [cOR] = 0.45; 0.34–0.62), continuous water access (cOR = 0.30; 0.20–0.43), fetching water daily (cOR = 0.77; 0.63–0.96), and breastfeeding (cOR = 0.65; 0.49–0.88) significantly reduced the likelihood of MSD. Fetching water in > 30 minutes (cOR = 2.56; 1.55–4.23) was associated with MSD. Piped tap water and courier-delivered water contained high (> 2 mg/L) concentrations of free residual chlorine and no detectable Escherichia coli. However, many households stored water overnight, resulting in inadequate free residual chlorine (< 0.2 mg/L) for preventing microbial contamination. Coliforms and E. coli were detected in 48% and 8% of stored household water samples, respectively. Although most of Bamako's population enjoys access to an improved water source, water quality is often compromised during household storage.
High Anti-Cryptosporidium parvum IgG Seroprevalence in HIV-Infected Adults in Limpopo, South Africa
Authors: Bartelt Luther A. , Sevilleja Jesus Emmanuel , Barrett Leah J. , Warren Cirle A. , Guerrant Richard L. , Bessong Pascal O. , Dillingham Rebecca , Samie Amidou
Published: July 2013

A seroepidemiological study was performed to determine the seroprevalence of Cryptosporidium in human immunodeficiency virus (HIV)-infected adults and local university students in the Limpopo Province, South Africa. Using a custom anti-C. parvum immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA), the seroprevalence of Cryptosporidium was found to be significantly higher (75.3%; 146 of 193) in HIV-infected individuals compared with student volunteers (32.8%; 19 of 58) (P < 0.001). A more recent diagnosis of HIV was associated with anti-C. parvum IgG seropositivity, as was lower weight among HIV-infected women. This is the first seroepidemiologic study of Cryptosporidium in rural South Africa, and it shows high endemicity among the HIV-infected population. In addition to raising the possibility of significant Cryptosporidium-related morbidities, this finding reveals that in Limpopo and perhaps in other low-income, rural populations, interrupting waterborne pathogen transmission will require strategies effective against environmentally hardy parasites such as Cryptosporidium.
Molecular Surveillance as Monitoring Tool for Drug-Resistant Plasmodium falciparum in Suriname
Authors: Adhin Malti R. , Labadie-Bracho Mergiory , Bretas Gustavo
Published: July 2013

The aim of this translational study was to show the use of molecular surveillance for polymorphisms and copy number as a monitoring tool to track the emergence and dynamics of Plasmodium falciparum drug resistance. A molecular baseline for Suriname was established in 2005, with P. falciparum chloroquine resistance transporter (pfcrt) and P. falciparum multidrug resistance (pfmdr1) markers and copy number in 40 samples. The baseline results revealed the existence of a uniformly distributed mutated genotype corresponding with the fully mefloquine-sensitive 7G8-like genotype (Y184F, S1034C, N1042D, and D1246Y) and a fixed pfmdr1 N86 haplotype. All samples harbored the pivotal pfcrtK76T mutation, showing that chloroquine reintroduction should not yet be contemplated in Suriname. After 5 years, 40 samples were assessed to trace temporal changes in the status of pfmdr1 polymorphisms and copy number and showed minor genetic alterations in the pfmdr1 gene and no significant changes in copy number, thus providing scientific support for prolongation of the current drug policy in Suriname.
Domestically Acquired Fascioliasis in Northern California
Authors: Weisenberg Scott A. , Perlada David E.
Published: July 2013

Two cases of domestically acquired fascioliasis are reported. Patient One was a 63-year-old male who developed a febrile illness 2 months after eating watercress in Marin County. Patient Two was a 38-year-old male who had eaten watercress with Patient One, and also developed a febrile illness. Both patients had eosinophilia and liver lesions on imaging. Diagnosis was made by serology and treatment was with triclabendazole.
Effective Use of Household Water Treatment and Safe Storage in Response to the 2010 Haiti Earthquake
Authors: Lantagne Daniele , Clasen Thomas
Published: July 2013

When water supplies are compromised during an emergency, responders often recommend household water treatment and safe storage (HWTS) methods, such as boiling or chlorination. We evaluated the near- and longer-term impact of chlorine and filter products distributed shortly after the 2010 earthquake in Haiti. HWTS products were deemed as effective to use if they actually improved unsafe household drinking water to internationally accepted microbiological water quality standards. The acute emergency survey (442 households) was conducted within 8 weeks of emergency onset; the recovery survey (218 households) was conducted 10 months after onset. Effective use varied by HWTS product (from 8% to 63% of recipients in the acute phase and from 0% to 46% of recipients in the recovery phase). Higher rates of effective use were associated with programs that were underway in Haiti before the emergency, had a plan at initial distribution for program continuation, and distributed products with community health worker support and a safe storage container.
The Importance of Neurocysticercosis in Stroke in Rural Areas of a Developing Latin American Country
Authors: Del Brutto Oscar H. , Lama Julio
Published: July 2013

There is limited information on the prevalence of neurocysticercosis (NCC) among stroke patients, and no community-based survey has addressed this issue. We performed a 3-Phase, population-based study, to assess the prevalence and pathogenesis of stroke in a rural village of coastal Ecuador, where cysticercosis is highly endemic. Twenty stroke patients were found among 642 individuals ≥ 40 years of age. Eighteen of these patients underwent neuroimaging studies and no patient had evidence of NCC or angiitis of intracranial vessels. The serum immunoblot test for the detection of anticysticercal antibodies, performed in 15 of these 20 patients during a previous survey, were negative in 13 cases and the remaining two had a normal computed tomography of the head. This study suggests that NCC is not responsible for the increasing burden of stroke in rural areas of developing countries.
Growth of atmospheric nano-particles by heterogeneous nucleation of organic vapor
Authors: Wang J. , McGraw R. L. , Kuang C.
Published: July 2013

Abstract. Atmospheric aerosols play critical roles in air quality, public health, and visibility. In addition, they strongly influence climate by scattering solar radiation and by changing the reflectivity and lifetime of clouds. One major but still poorly understood source of atmospheric aerosols is new particle formation, which consists of the formation of thermodynamically stable clusters from trace gas molecules (homogeneous nucleation) followed by growth of these clusters to a detectable size (~3 nm). Because freshly nucleated clusters are most susceptible to loss due to high rate of coagulation with pre-existing aerosol population, the initial growth rate strongly influences the rate of new particle formation and ambient aerosol population. Whereas many field observations and modeling studies indicate that organics enhance the initial growth of the clusters and therefore new particle formation, thermodynamic considerations would suggest that the strong increase of equilibrium vapor concentration due to cluster surface curvature (Kelvin effect) may prevent ambient organics from condensing on these small clusters. Here, the contribution of organics to the initial cluster growth is described as heterogeneous nucleation of organic molecules onto these clusters. We find that the strong gradient in cluster population with respect to its size leads to positive cluster number flux. This positive flux drives the growth of clusters substantially smaller than the Kelvin diameter, conventionally considered the minimum particle size that can be grown through condensation. The conventional approach neglects the contribution from the cluster concentration gradient, and underestimates the cluster survival probabilities by a factor of up to 60 if early growth of clusters is due to both condensation of sulfuric acid and heterogeneous nucleation of organic vapors.
A theoretical model on the formation mechanism and kinetics of highly toxic air pollutants from halogenated formaldehydes reacted with halogen atoms
Authors: Ji Y. M. , Wang H. H. , Gao Y. P. , Li G. Y. , An T. C.
Published: July 2013

Abstract. The atmospheric reactions of halogenated formaldehydes with halogen atoms were investigated by high-accuracy molecular orbital calculation. Studies showed that halogen atoms could easily abstract hydrogen atom from halogenated formaldehydes to form halogenated formyl radical and hydrogen halide (HX). In specific areas with high concentration of halogen atoms, such as the marine boundary layer (MBL), halogenated formyl radical was easily to react with halogen atoms and finally transformed into HX and CO2 in the presence of water; otherwise, this radical was degraded to CO2, halogen gas, and halogenated oxide. By using the canonical variational transition state theory, the kinetics calculations were performed within a wide atmospheric temperature range of 200–368 K, and theoretical values agreed well with the available experimental data. Under atmospheric conditions, the rate constants decreased as altitude increased, and especially the rate constants of halogen atoms reaction with FCHO quickly reduced. Although the reactions of halogenated formaldehydes with F atoms were more easily occurred than did those with Cl and Br atoms, the two latter reactions were still important atmospheric degradation process, especially in the MBL. The modified Arrhenius formulas of rate constants within the atmospheric temperature range were fitted, which helped to understand the established atmospheric model and estimate the contribution of title reactions to atmospheric chemistry pollution.
Influence of future climate and cropland expansion on isoprene emissions and tropospheric ozone
Authors: Squire O. J. , Archibald A. T. , Beerling D. J. , Hewitt C. N. , Lathière J. , Pike R. C. , Telford P. J. , Pyle J. A.
Published: July 2013

Abstract. Over the 21st century, changes in CO2 levels, climate and land use are expected to alter the global distribution of vegetation, leading to changes in trace gas emissions from plants, including, importantly, the emissions of isoprene. This, combined with changes in anthropogenic emissions, has the potential to impact tropospheric ozone levels, which above a certain level are harmful to animals and vegetation. In this study we use a biogenic emissions model following the empirical parameterisation of the MEGAN model, with vegetation distributions calculated by the Sheffield Dynamic Global Vegetation Model (SDGVM) to calculate potential future (2095) changes in isoprene emissions caused by changes in climate, land use, and the inhibition of isoprene emissions by CO2. From the present day (2000) value of 467 Tg C yr-1, we find that the combined impact of these factors causes a net decrease in isoprene emissions of 259Tg C yr-1 (55%) with individual contributions of +78 Tg C yr-1 (climate change), −190 Tg C yr-1 (land use) and −147 Tg C yr-1 (CO2 inhibition). Using these isoprene emissions and changes in anthropogenic emissions, a series of integrations is conducted with the UM-UKCA chemistry-climate model with the aim of examining changes in ozone over the 21st century. Globally all combined future changes cause a decrease in the tropospheric ozone burden of 27 Tg (7%) from 379 Tg in the present day. At the surface, decreases in ozone of 6–10 ppb are calculated over the oceans and developed northern hemispheric regions due to reduced NOx transport by PAN and reductions in NOx emissions in these areas respectively. Increases of 4–6 ppb are calculated in the continental Tropics due to cropland expansion in these regions, increased CO2 inhibition of isoprene emissions, and higher temperatures due to climate change. These effects outweigh the decreases in tropical ozone caused by increased tropical isoprene emissions with climate change. Our land use change scenario consists of cropland expansion which is most pronounced in the Tropics. The Tropics are also where land use change causes the greatest increases in ozone. As such there is potential for increased crop exposure to harmful levels of ozone. However, we find that these ozone increases are still not large enough to raise ozone to such damaging levels.
PAH concentrations simulated with the AURAMS-PAH chemical transport model over Canada and the USA
Authors: Galarneau E. , Makar P. A. , Zheng Q. , Narayan J. , Zhang J. , Moran M. D. , Bari M. A. , Pathela S. , Chen A. , Chlumsky R.
Published: July 2013

Abstract. The off-line Eulerian AURAMS chemical transport model was adapted to simulate the atmospheric fate of seven PAHs: phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene + triphenylene, and benzo[a]pyrene. The model was then run for the year 2002 with hourly output on a~grid covering southern Canada and the continental USA with 42 km horizontal grid spacing. Model predictions were compared to ~ 5000 24 h average PAH measurements from 45 sites, eight of which also provided data on particle/gas partitioning which had been modelled using two alternative schemes. This is the first known regional modelling study for PAHs over a North American domain and the first modelling study at any scale to compare alternative particle/gas partitioning schemes against paired field measurements. Annual average modelled total (gas + particle) concentrations were statistically indistinguishable from measured values for fluoranthene, pyrene and benz[a]anthracene whereas the model underestimated concentrations of phenanthrene, anthracene and chrysene + triphenylene. Significance for benzo[a]pyrene performance was close to the statistical threshold and depended on the particle/gas partitioning scheme employed. On a day-to-day basis, the model simulated total PAH concentrations to the correct order of magnitude the majority of the time. Model performance differed substantially between measurement locations and the limited available evidence suggests that the model spatial resolution was too coarse to capture the distribution of concentrations in densely populated areas. A more detailed analysis of the factors influencing modelled particle/gas partitioning is warranted based on the findings in this study.
Single scattering by realistic, inhomogeneous mineral dust particles with stereogrammetric shapes
Authors: Lindqvist H. , Jokinen O. , Kandler K. , Scheuvens D. , Nousiainen T.
Published: July 2013

Abstract. Light scattering by single, inhomogeneous mineral dust particles was simulated based on shapes and compositions derived directly from measurements of real dust particles instead of using a mathematical shape model. We demonstrate the use of stereogrammetric shape retrieval method in the context of single-scattering modelling of mineral dust for four different dust types – all of them inhomogeneous – ranging from compact, equidimensional shapes to very elongated and aggregate shapes. The three-dimensional particle shapes were derived from stereo pairs of scanning-electron microscope images, and inhomogeneous composition was determined by mineralogical interpretation of localized elemental information based on energy-dispersive spectroscopy. Scattering computations were performed for particle equal-volume diameters from 0.08 μm up to 2.8 μm at 550 nm wavelength, using the discrete-dipole approximation. Particle-to-particle variation in scattering by mineral dust was found to be quite considerable and was not well reproduced by simplified shapes of homogeneous spheres, spheroids, or Gaussian random spheres. Effective-medium approximation results revealed that particle inhomogeneity should be accounted even for small amounts of absorbing media (here up to 2% of the volume), especially when considering scattering by inhomogeneous particles at size parameters 3
CellTracker Green labelling vs. rose bengal staining: CTG wins by points in distinguishing living from dead anoxia-impacted copepods and nematodes
Authors: Grego M. , Stachowitsch M. , De Troch M. , Riedel B.
Published: July 2013

Abstract. Hypoxia and anoxia have become a key threat to shallow coastal seas. Much is known about their impact on macrofauna, less on meiofauna. In an attempt to shed more light on the latter group, in particular from a process-oriented view, we experimentally induced short-term anoxia (1 week) in the northern Adriatic Sea (Mediterranean) and examined the two most abundant meiofauna taxa – harpacticoid copepods and nematodes. Both taxa also represent different ends of the tolerance spectrum, with copepods being the most sensitive and nematodes among the most tolerant. We compared two methods: CellTracker Green (CTG) – new labelling approach for meiofauna – with the traditional rose bengal (RB) staining method. CTG binds to active enzymes and therefore colours live organisms only. The two methods show considerable differences in the number of living and dead individuals of both meiofauna taxa. Generally, RB will stain dead but not yet decomposed copepods and nematodes equally as it does live ones. Specifically, RB significantly overestimated the number of living copepods in all sediment layers in anoxic samples, but not in any normoxic samples. In contrast, for nematodes, the methods did not show such a clear difference between anoxia and normoxia. RB overestimated the number of living nematodes in the top sediment layer of normoxic samples, which implies an overestimation of the overall live nematofauna. For monitoring and biodiversity studies, the RB method might be sufficient, but for more precise quantification of community degradation, especially after an oxygen depletion event, CTG labelling is a better tool. Moreover, it clearly highlights the surviving species within the copepod or nematode community. As already accepted for foraminiferal research, we demonstrate that the CTG labelling is also valid for other meiofauna groups.
Changes in soil carbon sequestration in Pinus massoniana forests along an urban-to-rural gradient of southern China
Authors: Chen H. , Zhang W. , Gilliam F. , Liu L. , Huang J. , Zhang T. , Wang W. , Mo J.
Published: July 2013

Abstract. Urbanization is accelerating globally, causing a variety of environmental changes such as increases in air temperature, precipitation, atmospheric CO2, and nitrogen (N) deposition. However, effects of these changes on forest soil carbon (C) sequestration remain largely unclear. Here we used urban-to-rural environmental gradients in Guangdong Province, southern China, to address the potential effects of these environmental changes on soil C sequestration in Pinus massoniana forests. In contrast with our expectations and earlier observations, soil C content in urban sites was significantly lower than those in suburban and rural sites. Lower soil C pools in urban sites were correlated with a significant decrease in fine root biomass and a potential increase in soil organic C decomposition. Variation of soil C pools was also a function of change in soil C fractions. Heavy fraction C content in urban sites was significantly lower than those in suburban and rural sites. By contrast, light fraction C content did not vary significantly along the urban-to-rural gradient. Our results suggest that urbanization-induced environmental changes may have negative effect on forest soil C.
Acid-base characteristics of the Grass Pond watershed in the Adirondack Mountains of New York State, USA: interactions among soil, vegetation and surface waters
Authors: McEathron K. M. , Mitchell M. J. , Zhang L.
Published: July 2013

Abstract. Grass Pond watershed is located within the southwestern Adirondack Mountain region of New York State, USA. This region receives some of the highest rates of acidic deposition in North America and is particularly sensitive to acidic inputs due to many of its soils having shallow depths and being generally base poor. Differences in soil chemistry and tree species between seven subwatersheds were examined in relation to acid-base characteristics of the seven major streams that drain into Grass Pond. Mineral soil pH, stream water BCS (base-cation surplus) and pH exhibited a positive correlation with sugar maple basal area (p = 0.055; 0.48 and 0.39, respectively). Black cherry basal area was inversely correlated with stream water BCS, ANC (acid neutralizing capacity)c and NO3- (p = 0.23; 0.24 and 0.20, respectively). Sugar maple basal areas were positively associated with watershed characteristics associated with the neutralization of atmospheric acidic inputs while in contrast, black cherry basal areas showed opposite relationships to these same watershed characteristics. Canonical correspondence analysis indicated that black cherry had a distinctive relationship with forest floor chemistry apart from the other tree species, specifically a strong positive association with forest floor NH4, while sugar maple had a distinctive relationship with stream chemistry variables, specifically a strong positive association with stream water ANCc, BCS and pH. Our results provide evidence that sugar maple is acid-intolerant or calciphilic tree species and also demonstrate that black cherry is likely an acid-tolerant tree species.
Gaining and losing stream reaches have opposite hydraulic conductivity distribution patterns
Authors: Chen X. , Dong W. , Ou G. , Wang Z. , Liu C.
Published: July 2013

Abstract. In gaining streams, groundwater seeps out into the streams. In losing streams, stream water moves into groundwater systems. The flow moving through the streambed sediments under these two types of hydrologic conditions is generally in opposite directions (upward vs. downward). The two opposite flow mechanisms affect the pore size and fine particle content of streambeds. Thus it is very likely that the opposite flow conditions affect the streambed hydraulic conductivity. However, comparisons of the hydraulic conductivity (K) of streambeds for losing and gaining streams are not well documented. In this study, we examined the K distribution patterns of sediments below the channel surface or stream banks for the Platte River and its tributaries in Nebraska, USA. Two contrasting vertical distribution patterns were observed from the test sites. In gaining reaches, hydraulic conductivity of the streambed decreased with the depth of the sediment cores. In losing reaches, hydraulic conductivity increased with the depth of the sediment cores. These contrasting patterns in the two types of streams were mostly attributed to flow directions during stream water and groundwater exchanges. In losing reaches, downward movement of water brought fine particle into the otherwise coarse sediment matrix, partially silting the pores. For gaining reaches, upward flow winnowed fine particles, increasing the pore spacing in the top parts of streambeds, leading to higher hydraulic conductivity in shallower parts of streambeds. These flux directions can impact K values to depths of greater than 5 m. At each study site, in situ permeameter tests were conducted to measure the K values of the shallow streambed layer. Statistical analyses indicated that K values from the sites of losing reaches were significantly different from the K values from the sites of gaining reaches.
Comparative assessment of predictions in ungauged basins – Part 2: Flood and low flow studies
Authors: Salinas J. L. , Laaha G. , Rogger M. , Parajka J. , Viglione A. , Sivapalan M. , Blöschl G.
Published: July 2013

Abstract. The objective of this paper is to assess the performance of methods that predict low flows and flood runoff in ungauged catchments. The aim is to learn from the similarities and differences between catchments in different places, and to interpret the differences in performance in terms of the underlying climate-landscape controls. The assessment is performed at two levels. The Level 1 assessment is a meta-analysis of 14 low flow prediction studies reported in the literature involving 3112 catchments, and 20 flood prediction studies involving 3023 catchments. The Level 2 assessment consists of a more focused and detailed analysis of individual basins from selected studies from Level 1 in terms of how the leave-one-out cross-validation performance depends on climate and catchment characteristics as well as on the regionalisation method. The results indicate that both flood and low flow predictions in ungauged catchments tend to be less accurate in arid than in humid climates and more accurate in large than in small catchments. There is also a tendency towards a somewhat lower performance of regressions than other methods in those studies that apply different methods in the same region, while geostatistical methods tend to perform better than other methods. Of the various flood regionalisation approaches, index methods show significantly lower performance in arid catchments than regression methods or geostatistical methods. For low flow regionalisation, regional regressions are generally better than global regressions.
A comparison between gradient descent and stochastic approaches for parameter optimization of a sea ice model
Authors: Sumata H. , Kauker F. , Gerdes R. , Köberle C. , Karcher M.
Published: July 2013

Abstract. Two types of optimization methods were applied to a parameter optimization problem in a coupled ocean–sea ice model of the Arctic, and applicability and efficiency of the respective methods were examined. One optimization utilizes a finite difference (FD) method based on a traditional gradient descent approach, while the other adopts a micro-genetic algorithm (μGA) as an example of a stochastic approach. The optimizations were performed by minimizing a cost function composed of model–data misfit of ice concentration, ice drift velocity and ice thickness. A series of optimizations were conducted that differ in the model formulation ("smoothed code" versus standard code) with respect to the FD method and in the population size and number of possibilities with respect to the μGA method. The FD method fails to estimate optimal parameters due to the ill-shaped nature of the cost function caused by the strong non-linearity of the system, whereas the genetic algorithms can effectively estimate near optimal parameters. The results of the study indicate that the sophisticated stochastic approach (μGA) is of practical use for parameter optimization of a coupled ocean–sea ice model with a medium-sized horizontal resolution of 50 km × 50 km as used in this study.
Combining in situ measurements and altimetry to estimate volume, heat and salt transport variability through the Faroe–Shetland Channel
Authors: Berx B. , Hansen B. , Østerhus S. , Larsen K. M. , Sherwin T. , Jochumsen K.
Published: July 2013

Abstract. From 1994 to 2011, instruments measuring ocean currents (Acoustic Doppler Current Profilers; ADCPs) have been moored on a section crossing the Faroe–Shetland Channel. Together with CTD (Conductivity Temperature Depth) measurements from regular research vessel occupations, they describe the flow field and water mass structure in the channel. Here, we use these data to calculate the average volume transport and properties of the flow of warm water through the channel from the Atlantic towards the Arctic, termed the Atlantic inflow. We find the average volume transport of this flow to be 2.7 ± 0.5 Sv (1 Sv = 106 m3 s–1) between the shelf edge on the Faroe side and the 150 m isobath on the Shetland side. The average heat transport (relative to 0 °C) was estimated to be 107 ± 21 TW (1 TW = 1012 W) and the average salt import to be 98 ± 20 × 106 kg s−1. Transport values for individual months, based on the ADCP data, include a large level of variability, but can be used to calibrate sea level height data from satellite altimetry. In this way, a time series of volume transport has been generated back to the beginning of satellite altimetry in December 1992. The Atlantic inflow has a seasonal variation in volume transport that peaks around the turn of the year and has an amplitude of 0.7 Sv. The Atlantic inflow has become warmer and more saline since 1994, but no equivalent trend in volume transport was observed.
Alpine permafrost thawing during the Medieval Warm Period identified from cryogenic cave carbonates
Authors: Luetscher M. , Borreguero M. , Moseley G. E. , Spötl C. , Edwards R. L.
Published: July 2013

Abstract. Coarse crystalline cryogenic cave carbonates (CCCcoarse) dated to the last glacial period are common in central European caves and provide convincing evidence of palaeo-permafrost during this time. Little is known, however, about the exact nature of the environment in which CCCcoarse formed as no modern analogue setting is known. Here, we report the first findings of sub-recent, albeit inactive, CCCcoarse from a cave of the Western Alps which is located in the present-day permafrost zone. The globular shape and the presence of ubiquitous euhedral crystal terminations are comparable to previously reported aggregates from the last glacial period and strongly suggest that these aggregates formed subaqueously in pools lacking agitation. Furthermore, stable isotope values of mm-sized spheroids point to calcite precipitation in a closed system with respect to CO2, strongly supporting the hypothesis of a cryogenic origin associated with the freezing of water ponds. U-series analyses revealed three clusters of late Holocene calcite precipitation intervals between 2129 and 751 a b2k. These ages correlate with known periods of elevated summer temperatures, suggesting that warming and thawing of the frozen catchment above the cave allowed water infiltration into the karst system. The growth of CCCcoarse resulted from the re-freezing of this water in the still cold karst cavities.
El legado gráfico arquitectónico de Armando Sol
Authors: Rivas Merino Víctor Manuel
Published: July 2013

Es así como a lo largo de la historia de la arquitectura salvadoreña, han existido personajes que han dejado huella a través de sus diseños y construcciones, que reflejan soluciones creativas, inmersas en un contexto social, económico y cultural de una época. Tal es el caso de Armando Sol, uno de los primeros arquitectos salvadoreños graduados en el exterior y que aportara al país, no sólo un legado arquitectónico, sino también un legado artístico que pocos conocen y que es necesario valorarlo, conservarlo y difundirlo, con la intensión de que la sociedad, pero sobretodo las nuevas generaciones de arquitectos en formación aprendan a respetar y a proteger nuestro patrimonio cultural edificado. DOI: http://dx.doi.org/10.5377/koot.v0i2.1149 Revista de Museología "Kóot" No.2 2010: 9-25
Personaje invitado: Concepción Clará de Guevara
Authors: De Guevara Concepción Clará
Published: July 2013

Es una de las primeras mujeres antropólogas salvadoreñas. Entre los cargos que ha desempeñado destacan: Jefa Sección Etnografía, Museo Nacional “David J. Guzmán”en el período de 1972-1977, Directora General de Cultura, Juventud y Deportes en el Ministerio de Educación de 1979 a 1980, Jefa del Departamento de Investigaciones de la Dirección de Patrimonio Cultural, desde 1981 hasta 1991. Además fue Investigadora del Departamento de Investigaciones de la Universidad Dr. José Matías Delgado en los años 1999 al 2007. La Licda. Clará de Guevara se ha desempeñado como catedrática en varias universidades, entre las que se pueden mencionar: Universidad de El Salvador, Universidad Tecnológica de El Salvador, Universidad Francisco Gavidia, Universidad Evangélica y Universidad Don Bosco. DOI: http://dx.doi.org/10.5377/koot.v0i2.1155 Revista de Museología "Kóot" No.2 2010: 101-114
The paradox of diversity in leadership and leadership for diversity
Authors: Bebbington Diane , Özbilgin Mustafa
Published: July 2013

The paradox of diversity is that successful diversity interventions require leadership support when diversity in leadership positions is so evidently lacking. In order to explore this paradox in the UK, we examine progress towards demographic diversity in leadership roles in the higher education sector, a sector in which there is much espoused support for diversity. Through a critical and comprehensive review of the literature, we illustrate the persistent nature of inequalities that hinder diversity and inclusion in leadership. We examine studies on salient forms of inequality in higher education leadership including research on gender, ethnicity, class, sexual orientation and disability. We show that leadership diversity remains a significant challenge for the higher education sector. Drawing on the example of this sector, we demonstrate that leadership occupies a contradictory space in terms of demographic diversity, both as the focus of criticism due to its homogeneous profile and counter-intuitively as an essential force for progress towards greater equality. We investigate the paradox of the relative homogeneity of higher education leadership set against its role for championing and promoting equality and identify ways in which demographic diversity as well as the progressive potential of higher education leadership may be fostered.
Appartenance syndicale et âgisme : approche comparée en Europe
Authors: Barel Yvan , Frémeaux Sandrine
Published: July 2013

Si le poids des syndicats constitue une variable contextuelle importante en matière de management de la diversité, l’incidence de l’appartenance syndicale en elle-même est moins connue. S’appuyant sur l’enquête ESS 2008-2009 sollicitée par la Commission Européenne et menée auprès de 48 141 individus répartis dans 25 pays européens, cette étude vise à apprécier l’impact négatif de l’appartenance syndicale sur l’âgisme envers les personnes âgées. Bien que l’appartenance syndicale dans les pays d’Europe du Nord est souvent expliquée par les avantages matériels auxquels elle ouvre droit, elle réduit davantage l’âgisme dans ces pays que dans les autres pays d’Europe.
Enjeux techniques, symboliques et politiques de la mesure de la diversité dans les entreprises et les organisations ?
Authors: Zannad Hédia , Cornet Annie , Stone Pete
Published: July 2013

Cet article vise à identifier les enjeux techniques, symboliques et politiques liés aux choix des indicateurs mobilisés dans une politique de gestion de la diversité. Ils doivent permettre de poser un diagnostic, d’assurer le suivi et de mesurer la performance de ces politiques. Notre objectif est de montrer la complexité de la démarche, liée à la difficulté de trouver les bons indicateurs mais aussi de leur donner du sens, considérant les préoccupations des dirigeants et managers, les contextes internes (culture organisationnelle, modes d’organisation du travail et politiques de GRH, secteur…) et externes (contexte socio-culturel, légal, économique) et des objectifs recherchés.
Universities and Community-Based Research in Developing Countries: Community Voice and Educational Provision in Rural Tanzania
Authors: Kamando Amina , Doyle Lesley
Published: July 2013

The main focus of recent research on the community engagement role of universities has been in developed countries, generally in towns and cities and usually conducted from the perspective of universities rather than the communities with which they engage. The purpose of this article is to investigate the community engagement role of universities in the rural areas of developing countries, and its potential for strengthening the voice of rural communities. The particular focus is on the provision of primary and secondary education. The article is based on the assumption that in order for community members to have both the capacity and the confidence to engage in political discourse for improving educational capacity and quality, they need the opportunity to become involved and well versed in the options available, beyond their own experience. Particular attention is given in the article to community-based research (CBR). CBR is explored from the perspectives of community members and local leaders in the government-community partnerships which have responsibility for the provision of primary and secondary education in rural Tanzania. The historical and policy background of the partnerships, together with findings from two case studies, provide the context for the article.
A Conceptual Understanding of Employability: The Employers' View in Rwanda
Authors: Bamwesiga Penelope Mbabazi
Published: July 2013

Many governments believe that investing in human capital should increase citizens' employability, which is why it is often presented as a solution to the problems of knowledge-based economies and societies, rising unemployment rates and economic competiveness. The aim of this study is to understand employers' views regarding the employability of graduates from higher education programmes in Rwanda. Employers of graduates in the programmes of Accounting, Agriculture, Education and Medicine were interviewed to obtain a broad understanding of their views. The key themes that emerged from the thematic analysis were professional skills, becoming changeable/formable and skilful practices. This study argues that the concept of employability needs to be viewed as contextual because understanding the professional and national contexts is fundamental to achieving a better understanding of graduates' employability.
Political Transitions, Value Change and Motorisation in 1970s Portugal
Authors: Sousa M. Luísa , Marques Rafael
Published: July 2013

During the revolutionary period of 1974–76, there was vigorous debate in Portugal regarding the role of automobiles in the desired new society. The dispute was reinforced by the first international oil crisis. Strong ideological rhetoric was deployed either to defend the potentially liberating role of the automobile or to condemn its ‘bourgeois' underpinnings. This debate influenced social movements, policies, perceptions and views of social actors, thus contributing to market distortions, a short-lived disappearance of luxury and sports cars and to the creation of new models deemed to be adapted to the ‘true’ needs of the Portuguese. It also contributed to changes in automobile assemblage industry, road policy and delays in the implementation of road safety measures. Environmental, safety and traffic concerns were subdued, for a while, by a more essentialist approach to car consumption, with opposing interests trying to define the social spirit of automobile ownership and usage. The political turmoil of the period and the lack of coherent and durable policies account for the period being an intermission and not the beginning of a new trend.