bluuebunny/crossref_metadata_2025 huggingface dataset:
Covert Exogenous Cross-Modality Orienting between Audition and Vision
Authors: Klein Raymond
Published: February 2018

Control of visual attention by auditory stimuli is explored in seven previously unpublished experiments that were presented at conferences in the late 1980s. Reaction time (RT) to luminance targets was found to be affected by the spatial congruence between the target and a preceding or simultaneous, and non-informative, auditory event, suggesting that localizable auditory stimuli exogenously (rapidly and automatically) capture visual attention. These cuing effects were obtained in the absence of eye movements and do not appear to be mediated merely by criterion adjustments. When the information value of the auditory event was placed in conflict with its location (i.e., a tone on the right indicated that the visual target was likely to appear on the left), it was found that at short stimulus onset asynchronies (SOAs) reaction time (RT) was faster for targets at the stimulated location, an effect that disappeared within 500 ms and was reversed by 1000 ms. This demonstrates that it requires over 500 ms for endogenous orienting in response to probabilistic information about target location to overcome the powerful exogenous control of visual attention by localizable auditory stimulation. Simple RT to auditory stimuli was unaffected by the spatial congruence of a preceding or simultaneous visual stimulus. When uninformative, neither pitch contours (rising/falling tones) nor pitch (high/low tones) produced significant visual orienting along the vertical midline. When the direction of a pitch contour indicated the likely location of a visual target, participants were able to shift their attention if the relation between the natural meaning and the probabilistic information was compatible (e.g., rising contour signaled that a upper target was likely) but not when it was incompatible. The relation of these 30-year-old experiments to contemporary findings and ideas is discussed.
3-D Numerical Investigation on Oxygen Transfer in a Horizontal Venturi Flow with Two Holes
Authors: Yin Zegao , Feng Yingnan , Wang Yanxu , Gao Chengyan , Ma Ningning
Published: February 2018

In order to investigate the dissolved oxygen increase caused by air suction in a horizontal Venturi flow with two holes, a 3-D computational fluid dynamics model was used to explore the water and bubble mixture flow, coupled with a dissolved oxygen transfer model. A series of experiments were conducted to validate the mathematical model. A relative saturation coefficient correlation was examined factoring in dissolved oxygen concentration at the inlet, water velocity at the inlet, the hole’s diameter, contraction ratio at throat section, and the downstream length of Venturi pipe. It was found that the relative saturation coefficient increases with increasing dissolved oxygen concentration at the inlet and downstream length of Venturi pipe respectively. However, it increases with decreasing water velocity at the inlet and contraction ratio at the throat section to some extent. The hole’s diameter plays a complex role in the relative saturation coefficient. The dimensional analysis method and the least square method were used to deduce a simple formula for the relative saturation coefficient, and this was consistent with related data.
Aide sociale à l’enfance : se construire comme adolescent. Deux récits, deux expériences de placement
Authors: Potin Émilie
Published: February 2018

Grandir en dehors de sa famille n’est pas une situation ordinaire. En France, 1 % des mineurs sont confiés à l’aide sociale à l’enfance par une mesure de placement. Pour autant, leur adolescence est-elle extraordinaire ? Quel est l’impact du placement sur les adolescents ? Comment ces derniers se saisissent-ils de la mesure de protection ? À partir d’une approche situant les logiques dominantes liées à la prise en charge des adolescents placés et d’une lecture centrée sur les récits d’expérience de deux adolescentes, l’objectif de cet article est de montrer les ressorts complexes de la construction adolescente et ses enjeux socioéducatifs dans le cadre contraint du système de protection de l’enfance.
[ARTICLE WITHDRAWN] miR-630 Inhibits Epithelial-to-Mesenchymal Transition (EMT) by Regulating the Wnt/β-Catenin Pathway in Gastric Cancer Cells
Authors: Li Dong , Tian Bo , Jin Xiaosheng
Published: February 2018

THIS ARTICLE WAS WITHDRAWN BY THE PUBLISHERS IN OCTOBER 2020.
Colloidal solution of silver nanoparticles for label-free colorimetric sensing of ammonia in aqueous solutions
Authors: Buccolieri Alessandro , Serra Antonio , Giancane Gabriele , Manno Daniela
Published: February 2018

Silver nanoparticles were synthesized in the presence of saccharides and ammonia (NH3) in the concentration range from 10−2 to 103 ppm to develop an optical sensor for NH3 in aqueous solutions. Ammonia affects the features of the nanoparticles obtained in a concentration-dependent manner as determined by UV–vis absorption analysis and TEM observations. Structural and morphological analysis provides the basis for the production of a colorimetric label-free sensor for ammonia. Overall, surface plasmon resonance increases when ammonia concentration rises, although the functional trend is not the same over the entire investigated ammonia concentration range. Three different ranges have been identified: very low ammonia concentrations from 0.01 to 0.2 ppm, high ammonia concentrations from 20 to 350 ppm and, most importantly, the intermediate or physiological range of ammonia from 0.5 to 10 ppm.
A Comparison of Two Recording Montages for Ocular Vestibular Evoked Myogenic Potentials in Patients with Superior Canal Dehiscence Syndrome
Authors: Makowiec Kathryn , McCaslin Devin , Hatton Kelsey
Published: February 2018

Objective:The purpose of this investigation was to evaluate the sensitivity and specificity of the ocular vestibular evoked myogenic potential (oVEMP) using two electrode montages in patients with confirmed unilateral superior semicircular canal dehiscence syndrome (SCDS).Study
Design:This study evaluated oVEMP response characteristics measured using two different electrode montages from 12 unilateral SCDS ears and 36 age-matched control ears (age range = 23‐66). The oVEMP responses were elicited using 500 Hz tone-burst air conduction stimuli presented
at an intensity of 95 dB nHL and a rate of 5.1/sec. The two electrode montages used are described as an “infraorbital” montage and a “belly-tendon” montage.Setting:Balance function laboratory embedded in a large, tertiary care otology clinic.Results:The
belly-tendon electrode montage resulted in significantly larger amplitude responses than the infraorbital electrode montage for the ears with SCDS and the normal control ears. For both electrode montages the ear with SCDS exhibited a significantly larger amplitude response, ∼50% larger
than the response amplitude from the normal control ear. The belly-tendon montage additionally produced larger median increases in amplitude compared with the infraorbital montage. Specifically, the median increase in oVEMP N1-P1 amplitudes using the belly-tendon montage was 39% greater in
control ears, 76% greater in the SCDS ears, and 17% greater in the contralateral SCDS ears.Conclusions:The belly-tendon electrode montage yields significantly larger oVEMP amplitude responses for participants with SCDS and normal control participants.
Anagrus dmitrievi sp. n. (Hymenoptera, Mymaridae), an egg parasitoid of Zyginidia eremita (Hemiptera, Cicadellidae), a pest of maize in Xinjiang, China
Authors: Li Qin , Hu Hongying , Triapitsyn Serguei V. , Yi Long , Lu Jiaxiong
Published: February 2018

A new Palaearctic species of Anagrus Haliday (Hymenoptera, Mymaridae), A. (Anagrus) dmitrievi Triapitsyn & Hu, sp. n., is described, diagnosed, and illustrated from Xinjiang Uyghur Autonomous Region of China. It was reared from parasitized eggs of the leafhopper Zyginidia (Zyginidia) eremita Zachvatkin (Hemiptera, Cicadellidae) on leaves of maize. A key to the 21 named species of Anagrus known from China is provided. Zyginidiaeremita is an important economic pest in Xinjiang, occurring in approximately 90% of maize fields. The phenology and life cycle of Z.eremita is summarized. Parasitism of its eggs by A.dmitrievi in maize fields was 12–75 % (average about 38 %), thus making it a rather effective natural enemy.
Factors Influencing Cyclotorsion During Photorefractive Keratectomy
Authors: Alipour Fateme , Veisi Hampa Fateme , Ashrafi Elham , Dehghani Shima
Published: February 2018

PURPOSE:

To determine predictive factors for intra-operative cyclotorsion in photorefractive keratectomy (PRK).

METHODS:

A retrospective statistical analysis of medical records pertaining to 3,996 eyes undergoing PRK was conducted. Outcome measures of this study were the likely existence of statistically significant relations between diverse and potentially influential factors and the occurrence of intraoperative cyclotorsion.

RESULTS:

A total of 96% of examined medical records indicated some degree of cyclotorsion with the absolute mean intraoperative value of 1.38° ± 1.67° (range: 0° to 13.6°). Absolute mean cyclotorsion showed no significant correlation with age (
r
= 0.14,
P
= .37). Female patients had significantly higher degrees of cyclotorsion versus males (
P
< .001). Right and left eyes showed no significant difference in absolute mean torsion (
P
= .05). Higher diopters of refractive errors, hyperopia, more than 2.00 diopters of cylinder, high pulse numbers (
r
= 0.26), and use of the advanced personalized treatment ablation algorithm were all significantly related to higher degrees of torsion (
P
< .0001). Ablation depth (
r
= 0.13) and surgeon appeared to be dependent factors.

CONCLUSIONS:

Incidence of intraoperative cyclotorsion is high in eyes undergoing PRK and most of them will experience some degree of torsion. Several diverse factors (sex, refractive error diopters, hyperopia, high cylinder, pulse numbers, and ablation algorithm) were significant predictors for higher degrees of the observed torsion.

[
J Refract Surg.
2018;34(2):106–112.]
Risk Factors for Epithelial Ingrowth Following Microkeratome-Assisted LASIK
Authors: Friehmann Asaf , Mimouni Michael , Nemet Arie Y. , Sela Tzahi , Munzer Gur , Kaiserman Igor
Published: February 2018

PURPOSE:

To analyze the incidence and risk factors associated with epithelial ingrowth following uncomplicated microkeratome-assisted LASIK.

METHODS:

All patients who underwent microkeratome-assisted LASIK between January 2006 and December 2014 in a single surgical center were reviewed. Epithelial ingrowth cases were identified and associated factors were assessed.

RESULTS:

Overall, 149 (0.49%) of 30,574 cases developed epithelial ingrowth. The epithelial ingrowth group was older compared to controls (35.3 ± 12.3 vs 31.7 ± 10.3 years,
P
= .001) and had a higher percentage of moderate to high hyperopia (13.7% vs 5.3%,
P
< .001), early postoperative flap slippage requiring flap repositioning (9.4% versus 2.8%,
P
< .001), or flap lifting for enhancement (48.6% vs 4.3%,
P
< .001), were treated with a smaller optic zone (6 mm) (37.7% vs 15.2%,
P
< .001), with a Moria M2 microkeratome (Moria SA, Antony, France) (70.1% vs 55.5%,
P
= .02), by low volume surgeons (n < 1,000) (5.8% vs 1.3%,
P
< .001), in a lower operating room temperature (22.3 ± 1.8 vs 22.8 ± 1.6,
P
= .005), and with a greater maximum ablation depth (67.3 ± 29.7 vs 57.3 ± 30.3,
P
< .001). There was a high incidence of epithelial ingrowth in the enhancement group compared to primary LASIK (4.8% vs 0.2%,
P
< .001). The time between treatments (primary and enhanced LASIK) was significantly greater in the epithelial ingrowth group (mean: 1,110 ± 870 vs 626 ± 662 days,
P
< .001). There was a significant rise in epithelial ingrowth rates as time between primary and enhancement LASIK increased, peaking at 4 to 5 years (
P
< .001). In multivariate analysis, flap lifting for enhancement (odds ratio [OR] = 19.5,
P
< .001), 6-mm optic zone (OR = 2.2,
P
< .001), moderate to severe hyperopia (OR = 2.4,
P =
.005), greater ablation depth (OR = 1.005,
P
< .001), and low volume surgeon (OR = 3.9,
P =
.01) were associated with epithelial ingrowth (total
R
2
= 15.4).

CONCLUSIONS:

The potential risk factors described above may forewarn surgeons as to which individuals merit closer observation for this complication.

[
J Refract Surg.
2018;34(2):100–105.]
La ciudad de Arcávica y la fundación del monasterio Servitano
Authors: Barroso Cabrera Rafael , Morin de Pablos Jorge
Published: February 2018

La ciudad de Arcávica fue durante el periodo visigodo uno de los tres obispados situados en la actual provincia de Cuenca junto a los de Segóbriga y Valeria. No aparece mencionada en las fuentes de forma directa, a excepción de las firmas de sus prelados en las actas conciliares. Aún así, evidencian la importancia de este yacimiento los numerosos restos arqueológicos localizados en torno al cerro que albergó la ciudad celtíbero-romana de Ercávica. No obstante, el interés de su estudio se centra sobre todo en el problema de la localización del monasterio Servitano fundado por el norteafricano Donato y sus setenta monjes. Su ubicación en tierras arcavicenses se presenta fundamental para la comprensión de la arqueología del yacimiento y de buena parte de la historia de España durante los cruciales años en que transcurren los reinados de Leovigildo y su hijo Recaredo.
La iglesia gaditana ante la crisis del Antiguo Régimen (1800-1833)
Authors: Morgado Arturo
Published: February 2018

Los primeros años del siglo XIX constituyen una etapa crítica en la historia de la Iglesia española ante el descenso de los efectivos clericales, el deterioro de sus bases económicas y la incidencia de los avatares políticos. Este trabajo pretende analizar este proceso en el marco concreto de la diócesis de Cádiz.
Fray Félix María de Arriete y Llano, 1864-1879 (I)
Authors: Chamizo de la Rubia José
Published: February 2018

Documentado estudio acerca del episcopado gaditano de Félix María de Arriete. Se estudia su biografía y sus relaciones con la política regional de la época. Este aspecto es particularmente notable por la relevancia que tuvieron, en la historia de España, los acontecimientos de aquellos años en Cádiz. Aquí se inició la Revolución de Septiembre y aquí se fraguó parte del anticlericalismo que se desarrolló durante el sexenio 1868-1874. A todo esto presta detallada atención el autor.
Estimation of Vital Rates for the Hawaiian Gallinule, a Cryptic, Endangered Waterbird
Authors: van Rees Charles B. , Chang Paul R. , Cosgrove Jillian , DesRochers David W. , Gee Hugo K.W. , Gutscher-Chutz Jennifer L. , Nadig Aaron , Nagata Stephanie E. , Silbernagle Mike , Underwood Jared G. , Uyehara Kim , Reed J. Michael
Published: February 2018

Vital rates describe the demographic traits of organisms and are an essential resource for wildlife managers to assess local resource conditions and to set objectives for and evaluate management actions. Endangered waterbirds on the Hawaiian Islands have been managed intensively at state and federal refuges since the 1970s, but with little quantitative research on their life history. Information on the vital rates of these taxa is needed to assess the efficacy of different management strategies and to target parts of the life cycle that may be limiting their recovery. Here, we present the most comprehensive data to date on the vital rates (reproduction and survival) of the Hawaiian gallinule Gallinula galeata sandvicensis, a behaviorally cryptic, endangered subspecies of wetland bird endemic to the Hawaiian Islands that is now found only on Kaua‘i and O‘ahu. We review unpublished reproduction data for 252 nests observed between 1979 and 2014 and assess a database of 1,620 sightings of 423 individually color-banded birds between 2004 and 2017. From the resighting data, we estimated annual apparent survival at two managed wetlands on O‘ahu using Cormack–Jolly–Seber models in program MARK. We found that Hawaiian gallinules have smaller mean clutch sizes than do other species in the genus Gallinula and that clutch sizes on Kaua‘i are larger than those on O‘ahu. The longest-lived bird in our dataset was recovered dead at age 7 y and 8 mo, and the youngest confirmed age at first breeding was 1 y and 11 mo. In 4 y of monitoring 14 wetland sites, we confirmed three interwetland movements on O‘ahu. In our pooled dataset, we found no statistically significant differences between managed and unmanaged wetlands in clutch size or reproductive success, but we acknowledge that there were limited data from unmanaged wetlands. Our best supported survival models estimated an overall annual apparent survival of 0.663 (95% CI = 0.572–0.759); detection varied across wetlands and study years. First-year survival is a key missing component in our understanding of the demography of Hawaiian gallinules. These data provide the foundation for quantitative management and assessment of extinction risk of this endangered subspecies.
Phytosociology of weed in the southwestern Goiás region
Authors: Santos Weverton Ferreira , Procópio Sérgio De Oliveira , Silva Alessandro Guerra da , Fernandes Marcelo Ferreira , Santos Eduardo Ribeiro dos
Published: February 2018

Roundup Ready® technology adoption and the cultivation of a second crop have changed chemical control methods and weed management in the southwest region of Goiás State, Brazil. Considering these changes, this study aimed to perform a phytosociological survey in areas with glyphosate resistant soybeans and conventional soybeans as the main harvest and sorghum, maize, millet or fallow in succession as the second harvest. A multivariate matrix of the floristic composition was constructed, and the indicator values of the individual number and dry biomass of species were measured. Based on the number of individuals, the species Chamaesyce hirta, Bidens subalternans, and Cissampelos ovolifolia were typical of areas cultivated with glyphosate-resistant soybean, while Euphorbia heterophyla presented indicator values of areas with conventional soybean cultivation. During the second harvest period, significant indicator values were observed for Crotalaria spectabilis in maize areas, Cenchrus echinatus in sorghum, and Commelina benghalensis, Sida glaziovii, Ipomoea grandifolia, Sida rhombifolia, and Ipomoea cordifolia in areas with millet. The species Conyza bonariensis was typical in the period before the herbicide application at post-emergence in harvest. Volunteer soybean presented as typical for the period before the herbicide application at post-emergence in the second harvest. Weeds that were difficult to control or were tolerant and resistant to the herbicide applications were recorded in the areas studied.
Fitting new constructal models for the thermal potential of earth-air heat exchangers
Authors: Ramalho Jairo Valões de Alencar , Brum Ruth Da Silva , Rocha Luiz Alberto Oliveira , Isoldi Liércio André , Santos Elizaldo Domingues dos , Sulzbacher Mariane
Published: February 2018

Relying on the Constructal Design method, this paper introduces new periodic models for the thermal potential of Earth-Air Heat Exchangers (Eahe). As a case study, it analyses the best spacing for three ducts arranged triangularly in order to maximize the heat transfer between soil and air. More specifically, the ratio  between the horizontal and vertical spaces among the ducts is set free to vary up to limiting global constraints. This paper aims to better understand how the variations in  affect the thermal performance of Eahe. As an additional contribution, some relationships between  and the thermal potential of Eahe are mathematically and continuously stated. This allows establishing additional results for the efficiency and energetic performance of Eahe, as well as recommend arrangements in the shape of isosceles triangles with base and height unitary.
Cutting Edge: De Novo Glucocorticoid Synthesis by Thymic Epithelial Cells Regulates Antigen-Specific Thymocyte Selection
Authors: Mittelstadt Paul R. , Taves Matthew D. , Ashwell Jonathan D.
Published: February 2018

Glucocorticoid (GC) signaling in thymocytes counters negative selection and promotes the generation of a self-tolerant yet Ag-responsive T cell repertoire. Whereas circulating GC are derived from the adrenals, GC are also synthesized de novo in the thymus. The significance of this local production is unknown. In this study we deleted 11β-hydroxylase, the enzyme that catalyzes the last step of GC biosynthesis, in thymic epithelial cells (TEC) or thymocytes. Like GC receptor–deficient T cells, T cells from mice lacking TEC-derived but not thymocyte-derived GC proliferated poorly to alloantigen, had a reduced antiviral response, and exhibited enhanced negative selection. Strikingly, basal expression of GC-responsive genes in thymocytes from mice lacking TEC-derived GC was reduced to the same degree as in GC receptor–deficient thymocytes, indicating that at steady-state the majority of biologically active GC are paracrine in origin. These findings demonstrate the importance of extra-adrenal GC even in the presence of circulating adrenal-derived GC.
Low-Dose Methotrexate Prevents Primary and Secondary Humoral Immune Responses and Induces Immune Tolerance to a Recombinant Immunotoxin
Authors: King Emily M. , Mazor Ronit , Çuburu Nicolas , Pastan Ira
Published: February 2018

Recombinant immunotoxins (RITs) are chimeric proteins being developed for cancer treatment. They are composed of an Ab fragment that targets a cancer Ag and a cytotoxic portion of Pseudomonas exotoxin A. They are effective for patients with hematologic malignancies with defective immunity, but their efficacy against solid tumors is limited by anti-drug Ab (ADA) responses in immune-competent patients. Pre-existing Abs or immune memory owing to previous toxin exposure represent additional hurdles because they induce rapid and strong ADA responses. Here, we evaluated the efficacy of methotrexate (MTX) to prevent ADA formation against the mesothelin-targeting RIT LMB-100 in naive mice and in mice with pre-existing Abs. We found that low-dose MTX combined with LMB-100 completely suppressed the formation of ADAs in a dose- and frequency-dependent manner. Suppression of the immune response restored blood levels of LMB-100 and prevented its neutralization. Furthermore, combination of MTX with LMB-100 did not compromise the immune response against a second Ag given after stopping MTX, indicating specific immune tolerance. Adoptive transfer of splenocytes suppressed Ab responses to LMB-100 in recipient mice, indicating a durable immune tolerance. We conclude that combination of MTX and LMB-100 is effective at preventing immune responses in a durable, Ag-specific manner. We propose combining low-dose MTX in immune-competent cancer patients receiving RIT therapy to prevent immunogenicity. This approach could be applied to other immunogenic therapeutic agents and to proteins for which there is pre-existing immunity.
Perfect and separating hash families: new bounds via the algorithmic cluster expansion local lemma
Authors: Procacci Aldo , Sanchis Remy
Published: February 2018

We present new lower bounds for the size of perfect and separating hash families ensuring their existence. Such new bounds are based on the algorithmic cluster expansion improved version of the Lovász local lemma, which also implies that the Moser–Tardos algorithm finds such hash families in polynomial time.
Associations between stormwater retention pond parameters and pollutant (suspended solids and metals) removal efficiencies
Authors: Brink IC , Kamish W
Published: February 2018

Presented in this paper are the results of correlational analyses and logistic regression between metal substances (Cd, Cu, Pb, Zn), as well as suspended solids removal, and physical pond parameters of 19 stormwater retention pond case studies obtained from the International Stormwater BMP database. Included are cross-correlations between metals and solids in pond influent, effluent and removals. The findings provide insights fundamental to further development of improved models and design guidelines for stormwater ponds. Indications were that (i) pond efficiencies differed between high and low influent concentrations and masses, (ii) concentration was an invalid indicator of correlations between substances in pond influent and effluent as well as the fractions of substances removed within ponds, (iii) total cadmium, copper, lead, zinc and total suspended solids (TSS) were associated in surface runoff and similarly removed within ponds, (iv) statistically significant correlations were often only found in data groups either above or below a specific statistic (quartile value, median) for specific pond parameters, indicating that removals may have been differently influenced by pond parameters over different data ranges, and (v) the volume within the permanent pool was of greater importance to pond efficiencies than the volume captured during storm events.
A glimpse into the littoral nutrient dynamics of a lake system connected to the sea
Authors: Taljaard S , Van Niekerk L , Lemley DA
Published: February 2018

In South Africa more than 80% of estuaries are small, dynamic and predominantly linear systems. Nutrient characteristics in these systems are mostly influenced by external catchment processes, except during extended periods of closure. However, a small percentage of the country’s estuaries (< 3%) comprise larger estuarine lakes mostly evolved from drowned river valleys. The physical properties of these systems suggest relatively low flushing rates, and the potentially stronger influence of in-situ processes on nutrient characteristics. This study investigates dissolved inorganic nutrient dynamics in the littoral zones of these estuarine lake systems, and potential influencing factors, using the Wilderness Lake System as a case study. Comparison of inter-annual and seasonal trends in dissolved inorganic nutrients (NOx-N, NH4-N and PO4-P) in river inflow and in the three lakes confirmed that external catchment fluxes are most likely not the sole, or even the dominant drivers of average long-term or seasonal dissolved inorganic nutrient patterns in the lake littoral zones. Relatively low NOx:NH4 ratios (mostly less than 1) in the lakes (especially in Eilandvlei and Langvlei) indicated a stronger influence of in-situ processes, such as bacteriological remineralisation, similar to observations in other lake type systems with low flushing rates. Low NO3:NH4 ratios are known to stimulate cyanobacteria, having the metabolic ability to potentially produce microcystins. Therefore, incremental dissolved inorganic nutrient and organic matter enrichment may cause these systems to tip into eutrophic, possibly toxic, aquatic states that will be difficult, if not impossible, to reverse given their weak flushing mechanisms. The findings from this study highlight the importance of appropriate water resource management, both in the catchments and within the floodplains of estuarine lake systems.
Severe weather over the Highveld of South Africa during November 2016
Authors: Simpson Lee-ann , Dyson Liesl L
Published: February 2018

November months are notorious for severe weather over the Highveld of South Africa. November 2016 was no exception and a large number of severe events occurred. Very heavy rainfall, large hail and tornadoes were reported. The aim of this paper is to compare the synoptic circulation of November 2016 with the long-term mean November circulation and to investigate some sounding derived parameters. Furthermore, a few of the severe weather events are described in detail. The surface temperatures and dewpoint temperatures were found to be higher than normal resulting in increased conditional instability over the Highveld. Low-level moisture originated over the warm Mozambique Channel and the 500 hPa temperature trough was located favourably over the Highveld; further east than normal. The combination of these factors and weak steering winds resulted in flash flooding on the 9th while favourable wind shear conditions caused the development of a tornado on 15 November. The favourable circulation patterns and moisture gave rise to an atmosphere in which severe weather was a possibility, and the awareness of such factors is used as one of many tools when considering the severe weather forecast. The consideration of the daily variables derived from sounding data were good precursors for the prediction of severe thunderstorm development over the Highveld during November 2016. It is recommended that an operational meteorologist incorporates upper air sounding data into the forecasting process and not to rely on numerical prediction models exclusively.
Efficient N2O5 Uptake and NO3 Oxidation in the Outflow of Urban Beijing
Authors: Wang Haichao , Lu Keding , Guo Song , Wu Zhijun , Shang Dongjie , Tan Zhaofeng , Wang Yujue , Le Breton Michael , Zhu Wenfei , Lou Shengrong , Tang Mingjin , Wu Yusheng , Zheng Jing , Zeng Limin , Hallquist Mattias , Hu Min , Zhang Yuanhang
Published: February 2018

Abstract. Nocturnal reactive nitrogen compounds are important for understanding regional air pollution. Here we present the measurements of dinitrogen pentoxide (N2O5) associated with nitryl chloride (ClNO2) and particulate nitrate (pNO3−) in a suburban site of Beijing in the summer of 2016. High levels of N2O5 and ClNO2 were observed in the outflow of the urban Beijing air masses, with 1-min average maxima of 937 pptv and 2.9 ppbv, respectively. The N2O5 uptake coefficients, γ, and ClNO2 yield, f, were experimentally determined from the observed parameters. The N2O5 uptake coefficient ranged from 0.012 to 0.055, with an average of 0.034 ± 0.018, which is in the upper range of previous field studies reported in North America and Europe but is a moderate value in the North China Plain (NCP), which reflects efficient N2O5 heterogeneous processes in Beijing. The ClNO2 yield exhibited high variability, with a range of 0.50 to unity and an average of 0.73 ± 0.25. The nighttime nitrate radical (NO3) was calculated assuming that the thermal equilibrium between NO3 and N2O5 was maintained. In NO2-rich air masses, the oxidation of nocturnal biogenic volatile organic compounds (BVOCs) was dominated by NO3 rather than O2. The production rate of organic nitrates (ONs) via NO2+BVOCs was significant, with an average of 0.11 ± 0.09 ppbv h−1. We highlight the importance of NO2 oxidation of VOCs in the formation of ONs and subsequent secondary organic aerosols in summer in Beijing. The capacities of BVOCs oxidation and ONs formation are maximized and independent of NOx under a high NOx/BVOCs ratio condition (>10), which indicates that the initial reduction of the NOx emission cannot help reduce the nocturnal formation of ONs.
Phosphorus limitation and heat stress decrease calcification in Emiliania huxleyi
Authors: Gerecht Andrea C. , Šupraha Luka , Langer Gerald , Henderiks Jorijntje
Published: February 2018

Abstract. Calcifying haptophytes (coccolithophores) sequester carbon in the form of organic and inorganic cellular components (coccoliths). We examined the effect of phosphorus (P) limitation and heat stress on particulate organic and inorganic carbon (calcite) production in the coccolithophore Emiliania huxleyi. Both environmental stressors are related to rising CO2 levels and affect carbon production in marine microalgae, which in turn impacts biogeochemical cycling. Using semi-continuous cultures, we show that P limitation and heat stress decrease the calcification rate in E. huxleyi. However, using batch cultures, we show that different culturing approaches (batch versus semi-continuous) induce different physiologies. This affects the ratio of particulate inorganic (PIC) to organic carbon (POC) and complicates general predictions on the effect of P limitation on the PIC  ∕  POC ratio. We found heat stress to increase P requirements in E. huxleyi, possibly leading to lower standing stocks in a warmer ocean, especially if this is linked to lower nutrient input. In summary, the predicted rise in global temperature and resulting decrease in nutrient availability may decrease CO2 sequestration by E. huxleyi through lower overall carbon production. Additionally, the export of carbon may be diminished by a decrease in calcification and a weaker coccolith ballasting effect.
Explaining CO2 fluctuations observed in snowpacks
Authors: Graham Laura , Risk David
Published: February 2018

Abstract. Winter soil carbon dioxide (CO2) respiration is a significant
and understudied component of the global carbon (C) cycle. Winter soil CO2
fluxes can be surprisingly variable, owing to physical factors such as
snowpack properties and wind. This study aimed to quantify the effects of
advective transport of CO2 in soil–snow systems on the subdiurnal to
diurnal (hours to days) timescale, use an enhanced diffusion model to
replicate the effects of CO2 concentration depletions from persistent
winds, and use a model–measure pairing to effectively explore what is
happening in the field. We took continuous measurements of CO2
concentration gradients and meteorological data at a site in the Cape Breton
Highlands of Nova Scotia, Canada, to determine the relationship between wind
speeds and CO2 levels in snowpacks. We adapted a soil CO2 diffusion
model for the soil–snow system and simulated stepwise changes in transport
rate over a broad range of plausible synthetic cases. The goal was to mimic
the changes we observed in CO2 snowpack concentration to help elucidate
the mechanisms (diffusion, advection) responsible for observed variations. On
subdiurnal to diurnal timescales with varying winds and constant snow
levels, a strong negative relationship between wind speed and CO2
concentration within the snowpack was often identified. Modelling clearly
demonstrated that diffusion alone was unable to replicate the high-frequency
CO2 fluctuations, but simulations using above-atmospheric snowpack
diffusivities (simulating advective transport within the snowpack) reproduced
snow CO2 changes of the observed magnitude and speed. This confirmed that
wind-induced ventilation contributed to episodic pulsed emissions from the
snow surface and to suppressed snowpack concentrations. This study improves
our understanding of winter CO2 dynamics to aid in continued
quantification of the annual global C cycle and demonstrates a preference
for continuous wintertime CO2 flux measurement systems.
Insights into Atlantic multidecadal variability using the Last Millennium Reanalysis framework
Authors: Singh Hansi K. A. , Hakim Gregory J. , Tardif Robert , Emile-Geay Julien , Noone David C.
Published: February 2018

Abstract. The Last Millennium Reanalysis (LMR) employs a data assimilation
approach to reconstruct climate fields from annually resolved proxy
data over years 0–2000 CE. We use the LMR to examine Atlantic
multidecadal variability (AMV) over the last 2 millennia and find
several robust thermodynamic features associated with a positive
Atlantic Multidecadal Oscillation (AMO) index that reveal a
dynamically consistent pattern of variability: the Atlantic and most
continents warm; sea ice thins over the Arctic and retreats over the
Greenland, Iceland, and Norwegian seas; and equatorial precipitation
shifts northward. The latter is consistent with anomalous southward
energy transport mediated by the atmosphere. Net downward shortwave
radiation increases at both the top of the atmosphere and the surface,
indicating a decrease in planetary albedo, likely due to a decrease
in low clouds. Heat is absorbed by the climate system and the
oceans warm. Wavelet analysis of the AMO time series shows a
reddening of the frequency spectrum on the 50- to 100-year timescale, but no evidence of a distinct multidecadal or centennial
spectral peak. This latter result is insensitive to both the choice of
prior model and the calibration dataset used in the data assimilation
algorithm, suggesting that the lack of a distinct multidecadal
spectral peak is a robust result.
Dead Sea evaporation by eddy covariance measurements vs. aerodynamic, energy budget, Priestley–Taylor, and Penman estimates
Authors: Metzger Jutta , Nied Manuela , Corsmeier Ulrich , Kleffmann Jörg , Kottmeier Christoph
Published: February 2018

Abstract. The Dead Sea is a terminal lake, located in an arid environment. Evaporation is the key component of the Dead Sea water budget and accounts for the main loss of water. So far, lake evaporation has been determined by indirect methods only and not measured directly. Consequently, the governing factors of evaporation are unknown. For the first time, long-term eddy covariance measurements were performed at the western Dead Sea shore for a period of 1 year by implementing a new concept for onshore lake evaporation measurements. To account for lake evaporation during offshore wind conditions, a robust and reliable multiple regression model was developed using the identified governing factors wind velocity and water vapour pressure deficit. An overall regression coefficient of 0.8 is achieved. The measurements show that the diurnal evaporation cycle is governed by three local wind systems: a lake breeze during daytime, strong downslope winds in the evening, and strong northerly along-valley flows during the night. After sunset, the strong winds cause half-hourly evaporation rates which are up to 100 % higher than during daytime. The median daily evaporation is 4.3 mm d−1 in July and 1.1 mm d−1 in December. The annual evaporation of the water surface at the measurement location was 994±88 mm a−1 from March 2014 until March 2015. Furthermore, the performance of indirect evaporation approaches was tested and compared to the measurements. The aerodynamic approach is applicable for sub-daily and multi-day calculations and attains correlation coefficients between 0.85 and 0.99. For the application of the Bowen ratio energy budget method and the Priestley–Taylor method, measurements of the heat storage term are inevitable on timescales up to 1 month. Otherwise strong seasonal biases occur. The Penman equation was adapted to calculate realistic evaporation, by using an empirically gained linear function for the heat storage term, achieving correlation coefficients between 0.92 and 0.97. In summary, this study introduces a new approach to measure lake evaporation with a station located at the shoreline, which is also transferable to other lakes. It provides the first directly measured Dead Sea evaporation rates as well as applicable methods for evaporation calculation. The first one enables us to further close the Dead Sea water budget, and the latter one enables us to facilitate water management in the region.
Micropalaeontological dating of the basal Cretaceous section of DSDP Site 249, Leg 25, Mozambique Ridge: implications for the timing of the southern Atlantic–Indian Ocean connection
Authors: Dunay Robert E. , Braham William , Cooper M. Kevin E. , Lester Martin , Tremolada Fabrizio
Published: February 2018

Abstract. Tectonic models suggest the absence of a deep water connection on the Mozambique Ridge during early Neocomian time. These models imply the initiation of a deep water connection between the southern Atlantic and Indian oceans formed during Barremian–earliest Aptian times. However, previous biostratigraphic studies of the earliest deep water sediments on the Mozambique Ridge suggest that the basal section is Neocomian in age. Here, we present a new biostratigraphic analysis undertaken to test this tectonic model and determine the earliest age of deep water sedimentation on the Mozambique Ridge. Core samples from the Cretaceous interval 222.05–406.32 m (Cores 19–32) of DSDP Site 249, Leg 25, were sampled for calcareous nannoplankton and palynological analysis. Most of the sampling was concentrated on the Lower Cretaceous interval below 294 m. Our results indicate that the lower sedimentary section is no older than Barremian and therefore provides support for the age proposed by the tectonic models.
Recent rift formation and impact on the structural integrity of the Brunt Ice Shelf, East Antarctica
Authors: De Rydt Jan , Gudmundsson G. Hilmar , Nagler Thomas , Wuite Jan , King Edward C.
Published: February 2018

Abstract. We report on the recent reactivation of a large rift in the Brunt Ice Shelf, East Antarctica, in December 2012 and the formation of a 50 km long new rift in October 2016. Observations from a suite of ground-based and remote sensing instruments between January 2000 and July 2017 were used to track progress of both rifts in unprecedented detail. Results reveal a steady accelerating trend in their width, in combination with alternating episodes of fast ( > 600 m day−1) and slow propagation of the rift tip, controlled by the heterogeneous structure of the ice shelf. A numerical ice flow model and a simple propagation algorithm based on the stress distribution in the ice shelf were successfully used to hindcast the observed trajectories and to simulate future rift progression under different assumptions. Results show a high likelihood of ice loss at the McDonald Ice Rumples, the only pinning point of the ice shelf. The nascent iceberg calving and associated reduction in pinning of the Brunt Ice Shelf may provide a uniquely monitored natural experiment of ice shelf variability and provoke a deeper understanding of similar processes elsewhere in Antarctica.
Access Barriers to Health Services Perceived by People Living With HIV and Their Families
Authors: Bran-Piedrahita Lemy , Gómez-Molina Sergio , Valencia-Arias Alejandro , Vélez-Holguín Rosa , Palacios-Moya Lucía , Acevedo-Correa Yesenia , Arias-Arciniegas Claudia
Published: February 2018

INTRODUCCTION: The Human Immunodeficiency Virus (HIV) is a retrovirus that destroys the body's T cells. Its advanced stage is the Acquired Immune Deficiency Syndrome (AIDS), since its onset, it has been extensively studied because of an associated burden of morbidity and also to understand the access barriers to diagnostic tests and the required treatment. Objective: To understand the barriers to access health services as perceived by adults living with HIV and their families in the city of Medellín (Colombia).METHODOLOGY: A qualitative investigation by using historical-hermeneutical approach was carried out, involving 23 participants (seropositive patients and their relatives). The information was collected through semi-structured interviews, later codified and analyzed based on Strauss and Corbin's Grounded Theory.RESULTS: In this study, the access barriers to health services as perceived by adults living with HIV and their families are represented in administrative constraints, affecting economic and interpersonal relationships as well as social nature that materialize the impact of the social stigmas created around the virus on the mental health of seropositive person and their closest affective environment.CONCLUSION: The stigma surrounding HIV leads seropositive people and their families to perceive it as a barrier to accessing cultural services, which demands greater intervention efforts by health authorities than other types of barriers in health systems.
Prevalence and Associated Factors of Attention Deficit Hyperactivity Disorder (ADHD) in a Rural Community, Central Thailand: A Mixed Methods Study
Authors: Sakboonyarat Boonsub , Chokcharoensap Kritchaporn , Sathuthum Nadcha , Chutchawalanon Soraya , Khamkaen Chawengsak , Sookkaew Wetawit , Thamwinitchai Jutatip , Phalakornkul Natthanon , Saelim Sila , Liwvorakul Pongpat , Khaengkhun Pornpun , Dilokkulwattana Patcharee , Puttakiaw Poomwit , Meesaeng Monai , Sukreeyapongse Orasit , Minanond Nond , Rangsin Ram
Published: February 2018

BACKGROUND: Attention Deficit Hyperactivity Disorder (ADHD) is one of the most common behavioral problems among children around the world including Thailand. The disease affects their life, parents and community when left untreated. Most information concerning ADHD in Thailand derives from hospital based studies. The present study aimed to determine the prevalence and associated factors of ADHD in a remote rural community.METHODS: A total of 495 primary school children were screened using the SNAP-IV. Positive screening cases were then diagnosed by pediatric psychiatrists according to the DSM-V criteria. Standardized questionnaires were used to collect demographic data and associated factors. A qualitative study using focus group discussions and indepth interviews was conducted to determine knowledge and perceptions regarding ADHD among teachers and main guardians.RESULTS: The prevalence of ADHD among children was 2.2%. Univariate and multivariate analysis showed that children with ADHD were associated with both familial and individual factors including being repeatedly inattentive or hyperactive in class, suspended from school, and changing school, a history of bullying and main guardians were not parents. Qualitative data showed that both main guardians and teachers had inadequate knowledge and misperceptions regarding children with ADHD. The local health care system could not detect this problem so the children with ADHD were not properly treated.CONCLUSION: Our data emphasized that ADHD was a problem in this remote rural community. Screening tests and referral systems for ADHD should be provided for rural communities.
Human Urine and Treated Domestic Effluent for Ornamental Sunflower Cultivation
Authors: Gonçalves Karoline S. , Bandeira Samir De S. , Bispo Gustavo A. , Paz Vital Pedro Da S. , Gheyi Hans R. , Ledo Carlos Alberto Da S.
Published: February 2018

This study aimed to evaluate growth and production of ornamental sunflower (Helianthuns annuus L.), cv. Anão de Jardim, irrigated with dilutions of human urine in treated domestic effluent. The experiment was carried out in completely randomized design with five treatments and four replicates, in a greenhouse. Treatments consisted of four dilutions of human urine (0, 2, 4 and 6%) in treated domestic effluent and fertilization with 50% of the recommendation of mineral fertilizer. Plants irrigated with human urine dilutions (2, 4 and 6%) in treated domestic effluent and fertilized with 50% of the recommendation of nitrogen (N) and potassium (K) showed reductions of growth and production, while those irrigated with 0% human urine dilution in treated domestic effluent and fertilized with 50% of N and K recommendation exhibited similar performance to those irrigated with public-supply water and fertilized with 100% of the recommendation of mineral fertilizer. The obtained results allow to infer on the viability of replacing public-supply water by treated domestic effluent for irrigation, with reduction of 50% in N and K fertilization, without prejudice to the growth and production of ornamental sunflower plants, cv. Anão de Jardim.