bluuebunny/crossref_metadata_2025 huggingface dataset:
A unified model for bedform development and equilibrium under unidirectional, oscillatory and combined‐flows
Authors: Perillo Mauricio M. , Best James L. , Yokokawa Miwa , Sekiguchi Tomohiro , Takagawa Tomohiro , Garcia Marcelo H.
Published: April 2014

The development of bedforms under unidirectional, oscillatory and combined‐flows results from temporal changes in sediment transport, flow and morphological response. In such flows, the bedform characteristics (for example, height, wavelength and shape) change over time, from their initiation to equilibrium with the imposed conditions, even if the flow conditions remain unchanged. These variations in bedform morphology during development are reflected in the sedimentary structures preserved in the rock record. Hence, understanding the time and morphological development in which bedforms evolve to an equilibrium stage is critical for informed reconstruction of the ancient sedimentary record. This article presents results from a laboratory flume study on bedform development and equilibrium development time conducted under purely unidirectional, purely oscillatory and combined‐flow conditions, which aimed to test and extend an empirical model developed in past work solely for unidirectional ripples. The present results yield a unified model for bedform development and equilibrium under unidirectional, oscillatory and combined‐flows. The experimental results show that the processes of bedform genesis and growth are common to all types of flows, and can be characterized into four stages: (i) incipient bedforms; (ii) growing bedforms; (iii) stabilizing bedforms; and (iv) fully developed bedforms. Furthermore, the development path of bedform; growth exhibits the same general trend for different flow types (for example, unidirectional, oscillatory and combined‐flows), bedform size (for example, small versus large ripples), bedform shape (for example, symmetrical or rounded), bedform planform geometry (for example, two‐dimensional versus three‐dimensional), flow velocities and sediment grain sizes. The equilibrium time for a wide range of bed configurations was determined and found to be inversely proportional to the sediment transport flux occurring for that flow condition.
Is burnout solely job‐related? A critical comment
Authors: Bianchi Renzo , Truchot Didier , Laurent Eric , Brisson Romain , Schonfeld Irvin Sam
Published: April 2014

Within the field‐dominating, multidimensional theory of burnout, burnout is viewed as a work‐specific condition. As a consequence, the burnout syndrome cannot be investigated outside of the occupational domain. In the present paper, this restrictive view of burnout's scope is criticized and a rationale to decide between a work‐specific and a generic approach to burnout is presented. First, the idea that a multidimensional conception of burnout implies a work‐restricted scope is deconstructed. Second, it is shown that the burnout phenomenon cannot be confined to work because chronic, unresolvable stress – the putative cause of burnout – is not limited to work. In support of an integrative view of health, it is concluded that the field‐dominating, multidimensional theory of burnout should abandon as groundless the idea that burnout is a specifically job‐related phenomenon and define burnout as amulti‐domain syndrome. The shift from a work‐specific to a generic approach would allow both finer analysis and wider synthesis in research on chronic stress and burnout.
Getting Ahead and Falling Behind: A Sociological Elaboration of Sen's Theory of Human Development
Authors: Marsh Robert M.
Published: April 2014

Objective

One relatively neglected question raised by Amartya Sen's theory of human development is: Why do people and societies differ in their capacity to convert income and commodities into valuable human achievements (“functionings” in Sen's terminology)? I focus upon the degree to which people in developed and developing societies realize each of the six diverse types of valued functionings: long life, schooling, living in a society with less income inequality and less gender inequality, more political freedom, and greater life satisfaction.

Methods

Using data from all societies with a population of over 1 million (N= 156), I first regress each type of functioning on societies’ GDP per capita to obtain the residual scores. These scores indicate which societies do better than expected, as expected, or worse than expected on the basis of their level of economic development.

Results and Conclusion

To explain these differences, I then estimate an ordinary least squares (OLS) regression model whose independent variables are economic growth rate, ethnolinguistic fractionalization, civil war fatalities, corruption, and several dummy variables for cultural regions of the world.
Is There a Political Bias? A Computational Analysis of Female Subjects' Coverage in Liberal and Conservative Newspapers
Authors: Shor Eran , van de Rijt Arnout , Ward Charles , Askar Saoussan , Skiena Steven
Published: April 2014

Objectives

One possible source for the gap in media coverage between female and male subjects is the political affiliation of the media source. The objective of this present study was to test whether there is a difference between more liberal and more conservative newspapers in coverage rates of female subjects.

Methods

We used computational methods to analyze a unique large‐scale data set (complied by the Lydia Text Analysis System) and compared the 2010 female coverage rates in 168 newspapers.

Results

Contrary to our expectations, we found that conservative media tend to cover female subjects no less (and even slightly more) than liberal media. However, the difference was no longer significant once we controlled for newspaper distribution.

Conclusion

The common view that liberal newspapers are more likely to cover female subjects was not supported by this study. Both conservative and liberal newspapers are much more likely to cover males.
Growing but not Developing: Long‐Term Effects of Clustering in the Peruvian Clothing Industry
Authors: Visser Evert‐Jan , Távara José I. , Villaran Fernando
Published: April 2014

This paper analyses how a cluster of clothing firms in Peru fared over a 15 year period. The question is how and why this cluster has changed. We collected data for 1993 and 2007, comparing clustered and dispersed firms. The cluster grew significantly in terms of the number of firms and employment, due to the attraction of trade activities towards the cluster. The productivity of clustered producers fell somewhat, although they maintain an advantage over dispersed firms. This is due to static advantages falling into a producer's lap once located in the area and developing at the level of transacting inputs and output. Clustered producers do not use profits to upgrade businesses but rather invest in real estate. On the whole, they are struggling. Enhancing the quality of cluster governance is critical to prevent a further decline of the production part of the cluster.
Cryptococcal meningitis post autologous stem cell transplantation
Authors: Chaaban S. , Wheat L.J. , Assi M.
Published: April 2014

Disseminated Cryptococcus disease occurs in patients with defective T‐cell immunity. Cryptococcal meningitis following autologous stem cell transplant (SCT) has been described previously in only 1 patient, 4 months post SCT and while off antifungal prophylaxis. We present a unique case of Cryptococcus meningitis pre‐engraftment after autologous SCT, while the patient was receiving fluconazole prophylaxis. A 41‐year‐old man with non‐Hodgkin's lymphoma underwent autologous SCT. Post‐transplant prophylaxis consisted of fluconazole 400 mg daily, levofloxacin 500 mg daily, and acyclovir 800 mg twice daily. On day 9 post transplant, he developed fever and headache. Peripheral white blood cell count (WBC) was 700/μL. Magnetic resonance imaging of the brain showed lesions consistent with meningoencephalitis. Cerebrospinal fluid (CSF) analysis revealed a WBC of 39 with 77% lymphocytes, protein 63, glucose 38, CSF pressure 20.5 cmH2O, and a positive cryptococcal antigen. CSF culture confirmed Cryptococcus neoformans. The patient was treated with liposomal amphotericin B 5 mg/kg intravenously daily, and flucytosine 37.5 mg/kg orally every 6 h. He was switched to fluconazole 400 mg daily after 3 weeks of amphotericin therapy, with sterilization of the CSF with negative CSFCryptococcus antigen and negative CSF culture. Review of the literature revealed 9 cases of cryptococcal disease in recipients of SCT. Median time of onset was 64 days post transplant. Only 3 meningitis cases were described; 2 of them after allogeneic SCT. Fungal prophylaxis with fluconazole post autologous SCT is recommended at least through engraftment, and for up to 100 days in high‐risk patients. A high index of suspicion is needed to diagnose and treat opportunistic infections, especially in the face of immunosuppression and despite adequate prophylaxis. Infection is usually fatal without treatment, thus prompt diagnosis and therapy might be life saving.
Soil‐transmitted helminths in southern highland Rwanda: associated factors and effectiveness of school‐based preventive chemotherapy
Authors: Staudacher Olga , Heimer Jakob , Steiner Florian , Kayonga Yvette , Havugimana Jean M. , Ignatius Ralf , Musemakweri Andre , Ngabo Fidele , Harms Gundel , Gahutu Jean‐Bosco , Mockenhaupt Frank P.
Published: April 2014

Objectives

Preventive chemotherapy of schoolchildren against soil‐transmitted helminths (STHs) is widely implemented in Rwanda. However, data on its actual efficacy are lacking. We assessed prevalence, associated factors and manifestation of STH infection among schoolchildren in southern highland Rwanda as well as cure and reinfection rates.

Methods

Six hundred and twenty‐two children (rural, 301; urban, 321) were included preceding the administration of a single dose of 500 mg mebendazole. Before treatment, and after 2 and 15 weeks, STH infection was determined by Kato‐Katz smears and by PCR assays for Ascaris lumbricoides. Clinical and anthropometric data, socio‐economic status and factors potentially associated with STH infection were assessed.

Results

Soil‐transmitted helminth (STH) infection was present in 38% of rural and in 13% of urban schoolchildren. Ascaris lumbricoides accounted for 96% of infections. Of these, one‐third was detected by PCR exclusively. Factors associated with STH infection differed greatly between rural and urban children. Likewise, STH infection was associated with stunting and anaemia only among urban children. The cure rate after 2 weeks was 92%. Among eight non‐cleared A. lumbricoides infections, seven were submicroscopic. Reinfection within 3 months occurred in 7%, but the rate was higher among rural children, and with initially present infection, particularly at comparatively high intensity.

Conclusions

The rural–urban difference in factors associated with STH infection and in reinfection rates highlights the need for targeted interventions to reduce transmission. PCR assays may help in detecting low‐level infections persisting after treatment. In southern Rwanda, mebendazole is highly effective against the STH infections predominated by A. lumbricoides.
A mathematical approach to estimate the efficacy of individual‐donation and minipool nucleic acid amplification test options in preventing transmission risk by window period and occult hepatitis B virus infections
Authors: Vermeulen Marion , van Drimmelen Harry , Coleman Charl , Mitchel Josephine , Reddy Ravi , Lelie Nico
Published: April 2014

Background

Sensitivity data from a head‐to‐head comparison study in South Africa were used to compare the efficacy of the Ultrio Plus assay in individual‐donation (ID) and minipool (MP)4 and MP8 formats with that of TaqScreen MP6 in preventing hepatitis B virus (HBV) transmission risk.

Study Design and Methods

The replicate nucleic acid test (NAT) results on 106 HBV NAT (Ultrio)‐yield samples and 29 HBV DNA (Ultrio)‐negative, hepatitis B surface antigen (HBsAg)‐positive samples were used to determine the viral load in copies/mL against the Eurohep HBV standard by probit analysis. Random viral load distributions were established in 32 pre‐HBsAg window period (WP), 15 post‐HBsAg WP, and 56 occult HBV infection (OBI) donations. Regression analysis of log viral load and Poisson distribution statistics of infectious HBV particles in blood components was used to predict infectivity and efficacy of NAT options in removing HBV transmission risk.

Results

For red blood cell transfusions (20 mL of plasma), the modeling predicted an Ultrio Plus ID‐NAT efficacy of 68 and 83% in removing WP and (antibody to hepatitis B surface antigen–negative) OBI transmission risk, respectively, compared to 52 and 49% by TaqScreen MP6. For 200 mL of fresh‐frozen plasma the estimated efficacy levels by these ID‐ and MP6‐NAT options reduced to 57 and 44% for WP and to 67 and 34% for OBI donations, respectively.

Conclusion

The efficacy of the currently available commercial NAT systems in reducing HBV transmission risk is mainly driven by the pool size and the transfusion plasma volume. The modeled OBI transmission risk and NAT efficacy levels were in line with those recently reported in three lookback studies and give more insight in the incremental safety provided by HBsAg and antibody to hepatitis B core antigen testing of ID‐NAT screened blood.
Use of Six Sigma Worksheets for assessment of internal and external failure costs associated with candidate quality control rules for an ADVIA 120 hematology analyzer
Authors: Cian Francesco , Villiers Elisabeth , Archer Joy , Pitorri Francesca , Freeman Kathleen
Published: April 2014

Background

Quality control (QC) validation is an essential tool in total quality management of a veterinary clinical pathology laboratory. Cost‐analysis can be a valuable technique to help identify an appropriate QC procedure for the laboratory, although this has never been reported in veterinary medicine.

Objective

The aim of this study was to determine the applicability of the Six Sigma Quality Cost Worksheets in the evaluation of possible candidate QC rules identified by QC validation.

Methods

Three months of internal QC records were analyzed. EZ Rules 3 software was used to evaluate candidate QC procedures, and the costs associated with the application of different QC rules were calculated using the Six Sigma Quality Cost Worksheets. The costs associated with the current and the candidate QC rules were compared, and the amount of cost savings was calculated.

Results

There was a significant saving when the candidate 1‐2.5s, n = 3 rule was applied instead of the currently utilized 1‐2s, n = 3 rule. The savings were 75% per year (£8232.5) based on re‐evaluating all of the patient samples in addition to the controls, and 72% per year (£822.4) based on re‐analyzing only the control materials. The savings were also shown to change accordingly with the number of samples analyzed and with the number of daily QC procedures performed.

Conclusions

These calculations demonstrated the importance of the selection of an appropriate QC procedure, and the usefulness of the Six Sigma Costs Worksheet in determining the most cost‐effective rule(s) when several candidate rules are identified by QC validation.
VO2max Characteristics of Elite Female Soccer Players, 1989–2007
Authors: Haugen Thomas A. , Tønnessen Espen , Hem Erlend , Leirstein Svein , Seiler Stephen
Published: April 2014

Purpose:

To quantify VO2max among female competitive soccer players as a function of performance level, field position, and age. In addition, the evolution of VO2max among world-class players over an 18-y period was quantified.

Methods:

Female players (N = 199, 22 ± 4 y, 63 ± 6 kg, height 169 ± 6 cm), including an Olympic winning squad, were tested for VO2max at the Norwegian Olympic Training Center between 1989 and 2007.

Results:

National-team players had 5% higher VO2max than 1st-division players (P = .042, d = 0.4), 13% higher than 2nd-division players (P < .001, d = 1.2), and 9% higher than junior players (P = .005, d = 1.0). Midfielders had 8% higher VO2max than goalkeepers (P = .048, d = 1.1). No significant differences were observed across outfield players or different age categories. There was a trend toward lower relative VO2max across time epochs.

Conclusions:

This study demonstrated that VO2max varies across playing-standard level in women’s soccer. No significant differences in VO2max were observed across outfield positions and age categories. Over time, there has been a slight negative development in VO2max among elite Norwegian soccer players.
The 30–15 Intermittent Fitness Test Versus the Yo-Yo Intermittent Recovery Test Level 1: Relationship and Sensitivity to Training
Authors: Buchheit Martin , Rabbani Alireza
Published: April 2014

The aim of the current study was to examine the relationship between performance of the Yo-Yo Intermittent Recovery Test Level 1 (Yo-YoIR1) and the 30–15 Intermittent Fitness Test (30-15IFT) and to compare the sensitivity of both tests to training. Fourteen young soccer players performed both tests before and after an 8-wk training intervention, which included 6 sessions/wk: 2 resistance training sessions, 2 high-intensity interval training sessions after technical training (4 sets of 3:30 min of generic running and small-sided games [4v4] during the first and second 4-wk periods, respectively [90–95% maximal HR], interspersed with 3 min at 60–70% maximal HR), and 2 tactical-only training sessions. There was a large correlation between 30-15IFT and Yo-YoIR1 (r = .75, 90% confidence limits [CL] 0.57;0.86). While within-test percentage changes suggested a greater sensitivity to training for the Yo-YoIR1 (+35%, 90%CL 24;45) than for the 30-15IFT (+7%; 4;10), these changes were similarly rated as almost certain (with chances for greater/similar/lower values after training of 100/0/0 for both tests) and moderate, ie, standardized difference, ES = +1.2 90%CL (0.9;1.5) for Yo-YoIR1 and ES = +1.1 (0.7;1.5) for 30-15IFT. The difference in the change between the 2 tests was clearly trivial (0/100/0, ES = –0.1, 90%CL –0.1;–0.1). Both tests might evaluate slightly different physical capacities, but their sensitivity to training is almost certainly similar. These results also highlight the importance of using standardized differences instead of percentage changes in performance to assess the actual training effect of an intervention.
Certified Athletic Trainers' Perspectives on Rehabilitation Adherence in Collegiate Athletic Training Settings
Authors: Granquist Megan D. , Podlog Leslie , Engel Joanna R. , Newland Aubrey
Published: April 2014

Context:

Adherence to sport-injury rehabilitation protocols may be pivotal in ensuring successful rehabilitation and return-to-play outcomes.

Objectives:

To investigate athletic trainers' perspectives related to the degree to which rehabilitation adherence is an issue in collegiate athletic training settings, gain insight from certified athletic trainers regarding the factors contributing to rehabilitation nonadherence (underadherence and overadherence), and ascertain views on the most effective means for promoting adherence.

Design:

Crosssectional, mixed methods.

Setting:

Collegiate athletic training in the United States.

Participants:

Certified athletic trainers (n = 479; 234 male, 245 female).

Main Outcome Measures:

Online survey consisting of 3 questions regarding rehabilitation adherence, each followed by an open-ended comments section. Descriptive statistics were calculated for quantitative items; hierarchical content analyses were conducted for qualitative items.

Results:

Most (98.3%) participants reported poor rehabilitation adherence to be a problem (1.7% = no problem, 29.2% = minor problem, 49.7% = problem, 19.4% = major problem), while most (98.96%) participants reported that they had athletes who exhibited poor rehabilitation adherence (1% = never, 71.4% = occasionally, 22.5% = often, 5% = always). In addition, the majority (97.91%) of participants reported that overadherence (eg, doing too much, failing to comply with activity restrictions, etc) was at least an occasional occurrence (2.1% = never, 69.3% = occasionally, 26.3% = often, 1.9% = always). Hierarchical content analyses regarding the constructs of poor adherence and overadherence revealed 4 major themes: the motivation to adhere, the development of good athletic trainer–athlete rapport and effective communication, athletic trainers' perception of the coaches' role in fostering adherence, and the influence of injury- or individual- (eg, injury severity, sport type, gender) specific characteristics on rehabilitation adherence.

Conclusions:

These results suggest that participants believe that underadherence (and to a lesser extent overadherence) is a frequent occurrence in collegiate athletic training settings. Strategies for enhancing rehabilitation adherence rates and preventing overadherence may therefore be important for optimizing rehabilitation outcomes.
Al12N12 nanocage as a potential sensor for phosgene detection
Authors: Baei Mohammad T. , Soltani Alireza , Hashemian Saeedeh , Mohammadian Hossein
Published: April 2014

To find a novel sensor for phosgene molecules, phosgene adsorption on Al12N12 nanocage was studied by using density functional calculations in terms of geometry, Gibbs free energy, energy gap, enthalpy changes, vibrational frequencies, work function, molecular electrostatic potential surface, and density of state analysis. It was found that the electronic properties of the Al12N12 nanocage are very sensitive to the presence of phosgene molecules so that the energy gap of the nanocage is changed about 31% after the adsorption process. Based on calculated results, the Al12N12 nanocage is expected to be a promising novel sensor for phosgene molecules without manipulating its structure through doping, chemical functionalization, etc.
Optimizing cable harvesting layout when using variable-length cable roads in central Europe
Authors: Bont Leo , Heinimann Hans Rudolf , Church Richard L.
Published: April 2014

One of the classic operations problems in forest management is the layout of a harvesting system. This paper addresses the design of a harvesting system in areas characterized by steep slopes requiring cable-based harvesting. Layout optimization often involves numerous potential cable alignments and a small number of potential landings. In this paper we develop a model that addresses steep slope conditions found in central Europe that involve a large number of potential landings and cable alignments. In addition we extend existing work by considering variable-length alternatives for each feasible cable alignment. We construct three models, one for single-length cable options and two for variable-length alternatives and test their efficacy in solving 18 different harvesting area problems. We show that one of the variable-length alternative models can be solved in computer times that are competitive with the single-length option model. Overall, the savings that can be attributed to variable-length options are modest, but the alignments found by the variable-length options models are more realistic from forest engineers’ points of view, which will aid in its use and adoption.
Hmodel, a Heterobasidion annosum model for even-aged Norway spruce stands
Authors: Honkaniemi Juha , Ojansuu Risto , Piri Tuula , Kasanen Risto , Lehtonen Mika , Salminen Hannu , Kalliokoski Tuomo , Mäkinen Harri
Published: April 2014

Heterobasidion annosum (Fr.) Bref. s.l., a group of fungi causing root rot, is a serious threat to Norway spruce (Picea abies (L.) Karst.) stands in northern Europe. A new stochastic spatial model (Hmodel) was developed to simulate H. annosum s.l. infection and spread within a stand. Hmodel was combined with the stand-level decision support system MOTTI, resulting in a platform for estimating H. annosum s.l. development and its effect on tree growth and timber quality. Three H. annosum s.l. scenarios, representing different levels of risk for H. annosum s.l. infections simulated for a typical Norway spruce stand in southern Finland, demonstrated that the mycelial growth rate in the roots of living trees was the most critical parameter influencing the simulation results. In addition, the simulation results indicated that the number of infected trees in the previous stand plays a major role in H. annosum s.l. dynamics within the subsequent tree generation. Hmodel was designed to be a flexible platform for researchers to simulate the effects of H. annosum s.l. on stand dynamics and, vice versa, the effects of different silvicultural methods on H. annosum s.l. dynamics.
Effects of calcium treatment on forest floor organic matter composition along an elevation gradient
Authors: Balaria Ankit , Johnson Chris E. , Groffman Peter M.
Published: April 2014

Calcium amendment is a restorative option for nutrient-depleted, acidic soils in the forests of the northeastern United States. We studied the effects of watershed-scale wollastonite (CaSiO3) application on the structural composition of soil organic matter (SOM) and hot-water-extractable organic matter (HWEOM) at the Hubbard Brook Experiment Forest in New Hampshire 7–9 years after treatment, along an elevation gradient. Soils in the high-elevation spruce–fir–birch (SFB) zone contained significantly greater amounts of HWEOM compared with lower elevation hardwood soils, likely due to differences in litter quality and slower decomposition rates in colder soils at higher elevation. The only significant difference in hot-water-extractable organic carbon concentration between reference and calcium-treated watersheds was in Oie horizons of the SFB zone, which also exhibited the greatest degree of soil chemical change after treatment. The 13C nuclear magnetic resonance (NMR) spectra showed no significant patterns in O-alkyl C abundance for either soil or HWEOM along the elevation gradient, suggesting that there were no elevation-related patterns in carbohydrate concentration. The general absence of long-term effects in this study suggests that effects of Ca amendment at this dosage on the composition of SOM were small or short-lived.
Bohmian quantization of the big-brake singularity
Authors: Pinto-Neto Nelson , Pantoja Diego Moraes
Published: April 2014

The aim of this paper is to study the quantum aspects of the big-brake singularity. This is a singularity where the expansion of the universe stops abruptly, with infinity deceleration, caused by the divergence of the pressure of the fluid which describes the matter content of the model. In order to obtain our results, we interpret the quantum solutions of the Wheeler–DeWitt equation obtained from the canonical quantization of the classical model using the de Broglie–Bohm (dBB) quantum theory. Analyzing the Bohmian trajectories, we show that when one approaches the big-brake singularity, the universe still stops expanding, but now with finite deceleration, and initiates a smooth contracting phase. The pressure and the curvature never diverge.
A differential equation for the transition probability B(E2)↑ and the resulting recursion relations connecting even–even nuclei
Authors: Pattnaik S. , Nayak R. C.
Published: April 2014

We obtain here a new relation for the reduced electric quadrupole transition probability B(E2)↑ of a given nucleus in terms of its derivatives with respect to neutron and proton numbers based on a similar local energy relation in the Infinite Nuclear Matter (INM) model of atomic nuclei, which is essentially built on the foundation of the Hugenholtz–Van Hove (HVH) theorem of many-body theory. Obviously, such a relation in the form of a differential equation is expected to be more powerful than the usual algebraic difference equations. Although the relation for B(E2)↑ has been perceived simply on the basis of a corresponding differential equation for the local energy in the INM model, its theoretical foundation otherwise has been clearly demonstrated. We further exploit the differential equation in using the very definitions of the derivatives to obtain two different recursion relations for B(E2)↑, connecting in each case three neighboring even–even nuclei from lower to higher mass numbers and vice versa. We demonstrate their numerical validity using available data throughout the nuclear chart and also explore their possible utility in predicting B(E2)↑ values.
The Anatomy and Physics of ZDR Columns: Investigating a Polarimetric Radar Signature with a Spectral Bin Microphysical Model
Authors: Kumjian Matthew R. , Khain Alexander P. , Benmoshe Nir , Ilotoviz Eyal , Ryzhkov Alexander V. , Phillips Vaughan T. J.
Published: April 2014

Polarimetric radar observations of deep convective storms frequently reveal columnar enhancements of differential reflectivity ZDR. Such “ZDR columns” can extend upward more than 3 km above the environmental 0°C level, indicative of supercooled liquid drops being lofted by the updraft. Previous observational and modeling studies of ZDR columns are reviewed. To address remaining questions, the Hebrew University Cloud Model, an advanced spectral bin microphysical model, is coupled with a polarimetric radar operator to simulate the formation and life cycle of ZDR columns in a deep convective continental storm. In doing so, the mechanisms by which ZDR columns are produced are clarified, including the formation of large raindrops in the updraft by recirculation of smaller raindrops formed aloft back into the updraft at low levels. The internal hydrometeor structure of ZDR columns is quantified, revealing the transition from supercooled liquid drops to freezing drops to hail with height in the ZDR column. The life cycle of ZDR columns from early formation, through growth to maturity, to demise is described, showing how hail falling out through the weakening or ascending updraft bubble dominates the reflectivity factor ZH, causing the death of the ZDR column and leaving behind its “ghost” of supercooled drops. In addition, the practical applications of ZDR columns and their evolution are explored. The height of the ZDR column is correlated with updraft strength, and the evolution of ZDR column height is correlated with increases in ZH and hail mass content at the ground after a lag of 10–15 min.
X-Band Polarimetric Observations of Cross Coupling in the Ice Phase of Convective Storms in Taiwan
Authors: Hubbert J. C. , Ellis S. M. , Chang W.-Y. , Liou Y.-C.
Published: April 2014

In this paper, experimental X-band polarimetric radar data from simultaneous transmission of horizontal (H) and vertical (V) polarizations (SHV) are shown, modeled, and microphysically interpreted. Both range–height indicator data and vertical-pointing X-band data from the Taiwan Experimental Atmospheric Mobile-Radar (TEAM-R) are presented. Some of the given X-band data are biased, which is very likely caused by cross coupling of the H and V transmitted waves as a result of aligned, canted ice crystals. Modeled SHV data are used to explain the observed polarimetric signatures. Coincident data from the National Center for Atmospheric Research S-band polarimetric radar (S-Pol) are presented to augment and support the X-band polarimetric observations and interpretations. The polarimetric S-Pol data are obtained via fast-alternating transmission of horizontal and vertical polarizations (FHV), and thus the S-band data are not contaminated by the cross coupling (except the linear depolarization ratio LDR) observed in the X-band data. The radar data reveal that there are regions in the ice phase where electric fields are apparently aligning ice crystals near vertically and thus causing negative specific differential phase Kdp. The vertical-pointing data also indicate the presence of preferentially aligned ice crystals that cause differential reflectivity Zdr and differential phase ϕdp to be strong functions of azimuth angle.
Imported and Storm-Generated Near-Ground Vertical Vorticity in a Simulated Supercell*
Authors: Dahl Johannes M. L. , Parker Matthew D. , Wicker Louis J.
Published: April 2014

The authors use a high-resolution supercell simulation to investigate the source of near-ground vertical vorticity by decomposing the vorticity vector into barotropic and nonbarotropic parts. This way, the roles of ambient and storm-generated vorticity can be isolated. A new Lagrangian technique is employed in which material fluid volume elements are tracked to analyze the rearrangement of ambient vortex-line segments. This contribution is interpreted as barotropic vorticity. The storm-generated vorticity is treated as the residual between the known total vorticity and the barotropic vorticity.

In the simulation the development of near-ground vertical vorticity is an outflow phenomenon. There are distinct “rivers” of cyclonic shear vorticity originating from the base of downdrafts that feed into the developing near-ground vortex. The origin of these rivers of vertical vorticity is primarily horizontal baroclinic production, which is maximized in the lowest few hundred meters AGL. Subsequently, this horizontal vorticity is tilted upward while the parcels are still descending. The barotropic vorticity remains mostly streamwise along the analyzed trajectories and does not acquire a large vertical component as the parcels reach the ground. Thus, the ambient vorticity that is imported into the storm contributes only a small fraction of the total near-ground vertical vorticity.
Simulated Convective Invigoration Processes at Trade Wind Cumulus Cold Pool Boundaries
Authors: Li Zhujun , Zuidema Paquita , Zhu Ping
Published: April 2014

Observations of precipitating trade wind cumuli show convective invigoration on the downwind side of their cold pools. The authors study convection and cold pools using a nested–Weather Research and Forecasting Model simulation of 19 January 2005—a day from the Rain in Cumulus over the Ocean experiment. The temperature and water vapor mixing ratio drops in simulated cold pools fall within the envelope of observed cases, and the wind enhancement matches observations more closely. Subcloud updrafts downwind and near the cold pool boundary are statistically compared to updrafts further from cold pools. Updrafts near cold pool outflows are moister than the other updrafts and are more likely to originate from overall moister regions. Cold pool–influenced updrafts tend to exceed the other updrafts in vertical velocity and are associated with more cloud liquid water. The strength of circulation within the cold pool boundary is unable to match that because of the low-level environmental wind shear, and the lifted updrafts advect faster than the environmental wind, thereby accessing the ambient environmental moisture converged by cold pool expansion. Cases with higher rain rates correspond to larger cloud cover through the shearing off of the upper-level cloud, consistent with observations. This study suggests that it is the ability of cold pools to lift thermodynamically favorable air that is critical for secondary convection of trade wind cumuli.
Measurements of Turbulent Mixing and Subsiding Shells in Trade Wind Cumuli
Authors: Katzwinkel Jeannine , Siebert Holger , Heus Thijs , Shaw Raymond A.
Published: April 2014

High-resolution measurements of the turbulent, thermodynamic, and microphysical structure of the edges of trade wind cumuli have been performed with the Airborne Cloud Turbulence Observation System. Lateral entrainment of subsaturated air into the cloud region leads to an evaporative cooling effect. The negatively buoyant air partly enhances the compensating downdraft, forming a subsiding shell at cloud edge. Based on the presented observations, the subsiding shell is divided into a turbulent and humid inner shell adjacent to the cloud interior and a nonbuoyant, nonturbulent outer shell. In the trade wind region, continuous development of shallow cumuli over the day allows for an analysis of the properties of both shells as a function of different cloud evolution stages. The shallow cumuli are divided into actively growing, decelerated, and dissolving based on cloud properties. As the cumuli evolve from actively growing to dissolving, the subsaturated environmental air is mixed deeper and deeper into the cloud region and the subsiding shell grows at the expense of the cloud. This measured evolution of the subsiding shell compares favorably with the predictions of a direct numerical simulation of an idealized subsiding shell. The thickness of the measured outer shell decreases with the evolution of the cumuli while the intensity of the downdraft is nearly constant.
Rainfall Changes over Southwestern Australia and Their Relationship to the Southern Annular Mode and ENSO
Authors: Raut Bhupendra A. , Jakob Christian , Reeder Michael J.
Published: April 2014

Since the 1970s, winter rainfall over coastal southwestern Australia (SWA) has decreased by 10%–20%, while summer rainfall has been increased by 40%–50% in the semiarid inland area. In this paper, a K-means algorithm is used to cluster rainfall patterns directly as opposed to the more conventional approach of clustering synoptic conditions (usually the mean sea level pressure) and inferring the associated rainfall. It is shown that the reduction in the coastal rainfall during winter is mainly due to fewer westerly fronts in June and July. The reduction in the frequency of strong fronts in June is responsible for half of the decreased rainfall in June–August (JJA), whereas the reduction in the frequency of weaker fronts in June and July accounts for a third of the total decrease. The increase in rainfall inland in December–February (DJF) is due to an increased frequency of easterly troughs in December and February. These rainfall patterns are linked to the southern annular mode (SAM) index and Southern Oscillation index (SOI). The reduction in coastal rainfall and the increase in rainfall inland are both related to the predominantly positive phase of SAM, especially when the phase of ENSO is neutral.
Climatology and Ingredients of Significant Severe Convection in High-Shear, Low-CAPE Environments
Authors: Sherburn Keith D. , Parker Matthew D.
Published: April 2014

High-shear, low-CAPE (HSLC) environments, here characterized by surface-based CAPE ≤ 500 J kg−1, most unstable parcel CAPE ≤ 1000 J kg−1, and 0–6-km shear vector magnitude ≥ 18 m s−1, occur at all times of day, across all seasons, and throughout the entire United States. HSLC environments represent a unique challenge for forecasters, as they occur frequently but produce severe weather a relatively low percentage of the time. Recent studies have primarily focused on improving nowcasting and warnings for events through the identification of radar signatures commonly associated with HSLC tornadoes. Few studies have investigated the forecasting of HSLC severe weather, despite the acknowledged poor performance of traditional tools and techniques. A general climatology of HSLC significant severe weather is presented, focusing on regional, diurnal, and annual trends. Through this climatology, it becomes apparent that multiple types of HSLC environments are possible, including surface-based cases with low lifted condensation levels and high-based convection cases. A statistical analysis of HSLC events and nulls from the southeastern and mid-Atlantic states is utilized to assess the performance of conventional composite parameters in HSLC environments. Additionally, a new composite parameter is introduced that utilizes the product of the statistically most skillful parameters in HSLC environments: the 0–3-km lapse rate, the 700–500-hPa lapse rate, and multiple wind and shear metrics. The strengths and weaknesses of these ingredients-based techniques are then reviewed, with an eye toward improving future HSLC severe weather forecasts.
Structural parameters affecting superconductivity in iron chalcogenides: A review
Authors: Mousavi T. , Grovenor C. R. M. , Speller S. C.
Published: April 2014

Iron chalcogenides are of great interest because they have the simplest structure in the Fe based superconductor family, and show low anisotropies, high upper critical fields and high critical current densities. These compounds can, therefore, be considered as reference materials to study the behaviour of all layered Fe based superconductors, both to advance fundamental physical understanding and to explore potential high field applications. Research carried out since the discovery of superconductivity in these iron chalcogenides in 2008 is reviewed to explore the effects of key parameters such as structure, stoichiometry, pressure, elemental substitutions and strain on superconductivity. The effect of these parameters on the superconducting transition temperature of Fe1+ySe and Fe1+yTe1−xSex materials is critically assessed and the published results compared in an attempt to elucidate the relationship between structural parameters and superconducting properties in these compounds. Challenges for future work are identified.
On anisotropy of ferritic ODS alloys
Authors: Serrano M. , García-Junceda A. , Hernández R. , Mayoral M. H.
Published: April 2014

Ferritic oxide dispersion strengthened (ODS) alloys are candidate materials to be used as cladding for long term fast reactors, due to their high strength at high temperature and good swelling and irradiation resistances. The fabrication of cladding tubes is usually made by a succession of cold deformation steps where a deformation induced anisotropic microstructure could take place, which would affect the mechanical behaviour of the tube. The characterisation of this microstructural anisotropy is one of the key issues in the development of cladding ODS tubes. In this paper, the microstructural anisotropy of a Fe–14Cr–ODS extruded bar and a Fe–12Cr–ODS plate is characterised and its effect on the mechanical properties is analysed by tensile, impact and small punch testing. In both materials, a reduction of the ductility is observed in the transverse specimens. In addition, the fracture behaviour seems to be strongly dependent on the location of the crack plane regarding the elongated grained microstructure.
Construction of a cDNA library for miniature pig mandibular deciduous molars
Authors: Song Tieli , Wu Tingting , Wei Fulan , Li Ang , Wang Fu , Xie Yilin , Liu Dayong , Fan Zhipeng , Wang Xuejiu , Cheng Shan , Zhang Chunmei , He Junqi , Wang Songlin
Published: April 2014

Background

The miniature pig provides an excellent experimental model for tooth morphogenesis because its diphyodont and heterodont dentition resembles that of humans. However, little information is available on the process of tooth development or the exact molecular mechanisms controlling tooth development in miniature pigs or humans. Thus, the analysis of gene expression related to each stage of tooth development is very important.

Results

In our study, after serial sections were made, the development of the crown of the miniature pigs’ mandibular deciduous molar could be divided into five main phases: dental lamina stage (E33-E35), bud stage (E35-E40), cap stage (E40-E50), early bell stage (E50-E60), and late bell stage (E60-E65). Total RNA was isolated from the tooth germ of miniature pig embryos at E35, E45, E50, and E60, and a cDNA library was constructed. Then, we identified cDNA sequences on a large scale screen for cDNA profiles in the developing mandibular deciduous molars (E35, E45, E50, and E60) of miniature pigs using Illumina Solexa deep sequencing. Microarray assay was used to detect the expression of genes. Lastly, through Unigene sequence analysis and cDNA expression pattern analysis at E45 and E60, we found that 12 up-regulated and 15 down-regulated genes during the four periods are highly conserved genes homologous with known Homo sapiens genes. Furthermore, there were 6 down-regulated and 2 up-regulated genes in the miniature pig that were highly homologous to Homo sapiens genes compared with those in the mouse.

Conclusion

Our results not only identify the specific transcriptome and cDNA profile in developing mandibular deciduous molars of the miniature pig, but also provide useful information for investigating the molecular mechanism of tooth development in the miniature pig.
Consumption of Cisatracurium in different age groups, using a closed loop computer controlled system
Authors: Joomye Shehzaad , Yan Donglai , Wang Haiyun , Zhou Guoqiang , Wang Guolin
Published: April 2014

Background

We devised this study to quantify the effect of age on the consumption of cisatracurium under general anaesthesia, using a computer controlled closed loop infusion system. We further investigated this effect on, sufentanil and propofol consumption.

Methods

74 patients of physical status I and II, requiring general anaesthesia for elective abdominal surgery, were assigned to three groups. Patients in group 1 were aged from 20 to 45, group 2 were from 46 to 64, and group 3 above 65 years old. General Anesthesia was maintained with propofol and muscle paralysis was maintained using a closed-loop computer controlled infusion of cisatracurium. For analgesia, intermittent bolus of sufentanil 10 μg was given.

Results

Cisatracurium consumption in group 1, 2 and 3 were 1.8 ± 0.3, 1.6 ± 0.4 and 1.3 ± 0.4 μg/kg/min respectively. There was significant difference of cisatracurium consumption between group 1 and 3 (P = 0.002), and the consumption of cisatracurium in group 3 was less as compared with group 2 (P = 0.04). The average recovery index of patients in group 1, 2 and 3 were 8.8 ± 2.6, 11.5 ± 2.9 and 12.7 ± 2.5 minutes respectively. There were difference between group 1 and 2 (P = 0.02). As compared with group 1, the recovery index was still longer in group 3 (P = 0.001). Patients in group 1, 2 and 3 consumed an average sufentanil 0.4 ± 0.1, 0.4 ± 0.1 and 0.3 ± 0.1 μg/kg/hr, respectively. There were statistical significant between group 1 and 3 (P < 0.0001), and the same trend was found between group 2 and 3 (P = 0.03). The Consumption of propofol in group 1, 2 and 3 were 5.1 ± 0.4, 4.3 ± 0.6 and 3.1 ± 0.5 mg/kg/hr. The difference in the propofol consumption was found statistically significant when comparing between any two groups.

Conclusion

We concluded that the sensitivity of anesthetic agents increased with age. Less medication was required to achieve a desirable effect in older patients specially those above 65 years of age, and the drug effect was prolonged.

Trial registration

ClinicalTrials.gov Identifier: NCT01785446.
Parasitic polymorphism of Coccidioidesspp
Authors: Muñoz-Hernández Bertha , Palma-Cortés Gabriel , Cabello-Gutiérrez Carlos , Martínez-Rivera María Angeles
Published: April 2014

Background

Coccidioides spp. is the ethiological agent of coccidioidomycosis, an infection that can be fatal. Its diagnosis is complicated, due to that it shares clinical and histopathological characteristics with other pulmonary mycoses. Coccidioides spp. is a dimorphic fungus and, in its saprobic phase, grows as a mycelium, forming a large amount of arthroconidia. In susceptible persons, arthroconidia induce dimorphic changes into spherules/endospores, a typical parasitic form of Coccidioides spp. In addition, the diversity of mycelial parasitic forms has been observed in clinical specimens; they are scarcely known and produce errors in diagnosis.

Methods

We presented a retrospective study of images from specimens of smears with 15% potassium hydroxide, cytology, and tissue biopsies of a histopathologic collection from patients with coccidioidomycosis seen at a tertiary-care hospital in Mexico City.

Results

The parasitic polymorphism of Coccidioides spp. observed in the clinical specimens was as follows: i) spherules/endospores in different maturation stages; ii) pleomorphic cells (septate hyphae, hyphae composed of ovoid and spherical cells, and arthroconidia), and iii) fungal ball formation (mycelia with septate hyphae and arthroconidia).

Conclusions

The parasitic polymorphism of Coccidioides spp. includes the following: spherules/endospores, arthroconidia, and different forms of mycelia. This knowledge is important for the accurate diagnosis of coccidioidomycosis. In earlier studies, we proposed the integration of this diversity of forms in the Coccidioides spp. parasitic cycle. The microhabitat surrounding the fungus into the host would favor the parasitic polymorphism of this fungus, and this environment may assist in the evolution toward parasitism of Coccidioides spp.