bluuebunny/crossref_metadata_2025 huggingface dataset:
Rising Trends in Emergency Department Visits Associated With Hepatitis C Virus Infection in the United States, 2006-2014
Authors: Yin Shaoman , Barker Laurie , Teshale Eyasu H. , Jiles Ruth B.
Published: October 2019

Objective:

Emergency departments (EDs) are critical settings for hepatitis C care in the United States. We assessed trends and characteristics of hepatitis C–associated ED visits during 2006-2014.

Methods:

We used data from the 2006-2014 Nationwide Emergency Department Sample to estimate numbers, rates, and costs of hepatitis C–associated ED visits, defined by either first-listed diagnosis of hepatitis C or all-listed diagnosis of hepatitis C. We assessed trends by demographic characteristics, liver disease severity, and patients’ disposition by using joinpoint analysis, and we calculated the average annual percentage change (AAPC) from 2006 to 2014.

Results:

During 2006-2014, the rate per 100 000 visits of first-listed and all-listed hepatitis C–associated ED visits increased significantly from 10.1 to 25.4 (AAPC = 13.0%; P < .001) and from 484.4 to 631.6 (AAPC = 3.4%; P < .001), respectively. Approximately 70% of these visits were made by persons born during 1945-1965 (baby boomers); 30% of visits were made by Medicare beneficiaries and 40% by Medicaid beneficiaries. Significant rate increases were among visits by baby boomers (first-listed: AAPC = 13.8%; all-listed: AAPC = 2.6%), persons born after 1965 (first-listed: AAPC = 14.3%; all-listed: AAPC = 9.2%), Medicare beneficiaries (first-listed: AAPC = 18.0%; all-listed: AAPC = 3.9%), and persons hospitalized after ED visits (first-listed: AAPC = 20.0%; all-listed: AAPC = 2.3%; all P < .001). Increasing proportions of compensated cirrhosis were among visits by baby boomers (first-listed: AAPC = 11.5%; all-listed: AAPC = 6.3%). Annual hepatitis C–associated total ED costs increased by 400.0% (first-listed) and 192.0% (all-listed) during 2006-2014.

Conclusion:

Public health efforts are needed to address the growing burden of hepatitis C care in the ED.
Scaling modeling and simulation on high-performance computing clusters
Authors: Mikailov Mike , Qiu Junshan , Luo Fu-Jyh , Whitney Stephen , Petrick Nicholas
Published: October 2019

Large-scale modeling and simulation (M&S) applications that do not require run-time inter-process communications can exhibit scaling problems when migrated to high-performance computing (HPC) clusters if traditional software parallelization techniques, such as POSIX multi-threading and the message passing interface, are used.

A comprehensive approach for scaling M&S applications on HPC clusters has been developed and is called “computation segmentation.” The computation segmentation is based on the built-in array job facility of job schedulers. If used correctly for appropriate applications, the array job approach provides significant benefits that are not obtainable using other methods. The parallelization illustrated in this paper becomes quite complex in its own right when applied to extremely large M&S tasks, particularly due to the need for nested loops. At the United States Food and Drug Administration, the approach has provided unsurpassed efficiency, flexibility, and scalability for work that can be performed using embarrassingly parallel algorithms.
Energy performance evaluation for benchmarking school buildings using dynamic clustering analysis and particle swarm optimization
Authors: Huang Hsu-Yao , Lin Lung-Chieh , Ke Ming-Tsun , Sathesh Tamilarasan , Lee Wen-Shing
Published: October 2019

Benchmarking the energy performance of buildings has received increasing attention as striving for energy efficiency through more effective energy management has become a major concern of governments. Various methods for classifying building energy performance have been developed, and the clustering technique is considered one of the best approaches. This paper proposes a method utilizing dynamic clustering to analyze the electricity consumption patterns of buildings to decide the optimal cluster number and allocate the buildings to corresponding clusters for energy benchmarking. For the evaluation of number of clusters, this article has employed the inter–intra clustering method with particle swarm optimization algorithm. The electricity consumption data were collected through an energy survey performed in 30 junior high schools in Taipei, Taiwan. In a traditional method, the 30 schools would be grouped into one same cluster and the energy benchmarking report an average value of 541.4 kWh/year per student. The proposed method that took different electricity consumption patterns of the schools into consideration produced more detailed results as follows: the optimal cluster number was 3 with an inter–intra index value of 0.708, and the energy benchmarking index of these three clusters read, respectively, 362, 512, and 851 kWh/year per student.

Practical application: The study proposed an innovative dynamic clustering technique to decide the optimal cluster number and allocate the assessed buildings. The results showed that compared to a traditional approach that tended to group assessed buildings into one cluster, the proposed method was able to classify the buildings into three clusters for further benchmarking. This method can be used by governments and large corporations. For example, in Hong Kong, primary schools are grouped into one cluster for energy benchmarking. Using the proposed method can further classify primary schools into more clusters; benchmarking index can then be developed for each cluster.
Wilms tumor with extensive cardiac thrombus: a multidisciplinary approach
Authors: Viswanathan Aarthi , Kumar Nuthan , Mathew Anand Kuriyan , Narendra Babu Munianjinappa , Subramanian Anand P , Appaji Lingappa
Published: October 2019

Wilms tumor is the second most common intraabdominal malignancy in childhood. Vessel invasion with thrombus formation is a well-known phenomenon in Wilms tumor and is found in 30% of these children. This report describes a 4-year-old boy with a left kidney Wilms tumor and extensive thrombi formation with intracardiac extension. He underwent a left radical nephrectomy under cardiopulmonary bypass following a single dose of chemotherapy. Emergency surgery with cardiopulmonary bypass may be lifesaving in children with cardiac compromise in the presence of extensive thrombosis.
Seeing doubles: On two of a kind
Authors: Noegel Scott B , Nichols Corinna E
Published: October 2019

This article expands upon a previously published study in this journal that examined a literary strategy which employs linguistic devices of doubling in biblical narratives that reference twins. It demonstrated that Israelite authors employed several devices, including dual forms, gemination, doubled vocabulary, polysemy, and paronomasia on the number ‘two’, in order to match form to content. Here, we add studies of four biblical passages (Judges 5, Proverbs 20, 30, 31) as well as a brief excursus on a similar strategy in the Epic of Gilgamesh, and we argue that the strategy of doubling also appears in narratives that feature pairs or the doubling of amounts (i.e. not necessarily texts that employ the term ‘twin’).
Strain rate-dependent characterization of carbon fibre-reinforced composite laminates using four-point bending tests
Authors: Rojas-Sanchez JF , Schmack T , Boesl B , Bjekovic R , Walther F
Published: October 2019

This research addresses the problem of accurately quantifying the strain rate effect of carbon fibre-reinforced plastics by proposing a method with a simple specimen manufacturing and experiment execution based on four-point bending tests. By easing the strain rate-dependent characterization of carbon fibre-reinforced plastics, less conservative designs can be achieved. The method proposed uses Euler–Bernoulli and Timoshenko’s beam theories to obtain the longitudinal compressive and tensile modulus, compressive strength, shear modulus, and shear yielding point. Transverse properties could not be obtained due to limitations of the fixture employed. A strain-dependent material characterization was done using the proposed method and compared to the characterization of the same material using traditional uniaxial tests. Most of the material properties obtained with different methods correlated within approximately 10%. More work needs to be done to determine how this discrepancy affects simulation results.
Theoretical study on the effect of the anti-yaw damper for rail vehicles
Authors: Xia Zhanghui , Zhou Jinsong , Gong Dao , Sun Wenjing , Sun Yu
Published: October 2019

Simplification of a complex model is an analytical method commonly adopted in engineering design and academic research. A simplified theoretical analysis model can help project planners or researchers to develop an integrative view of the effect of each component on the system performances, which allows them to understand the related engineering phenomena and make proper engineering judgments. Based on the widely used Maxwell constitutive model for anti-yaw dampers, a simple 4 degree-of-freedom model is established to derive a set of analytical formulas, including those for critical speed, anti-yaw damper force transfer function, and rational resistance factor, which control the stability, ride quality, and curving performance of rail vehicles, respectively. Based on the proposed analytical formulas, the impact of damper parameters and mounting positions of the anti-yaw damper on the stability, ride quality and curving performance are analyzed. Finally, trade-offs among stability, ride quality, and curving performance are also discussed.
Removal of cadmium from waters by adsorption using nanochitosan
Authors: Alyasi Haya , Mackey Hamish R , McKay Gordon
Published: October 2019

This study is based on the removal of cadmium from water by adsorption onto nanochitosan in order to reduce the impact of cadmium toxicity to humans and animals. The adsorption of cadmium onto this particular nanochitosan is a novel study assessed through equilibrium and kinetic experiments. It provides an effective method of cadmium removal to avoid cadmium health impacts described herein. The influence of different parameters on the effectiveness and efficiency of cadmium adsorption onto nanochitosan are presented by studying the effects of pH, initial cadmium concentration and the dosage of nanochitosan. Commonly used equilibrium models are described, and the discussion focuses on an analysis of different isotherm and kinetic models to determine the best fit model for predicting the cadmium–nanochitosan adsorption capacity. All models were studied for their statistical significance using two error methods; the Sum of Squared Error to the natural experimental data and the R2 method to the linearised experimental data. Since the R2 values were very close, the best fit is described according to the findings of the minimum Sum of Squared Error values. The capacity of nanochitosan was found to be 1.96 mmol Cd/g adsorbent. Most previous research studies propose a Langmuir equilibrium model for the adsorption of cadmium on chitosan and nanochitosan; however in the present study, three isotherms were tested; the best fit isotherm was the SIPS followed by the Langmuir, and the best fit kinetic model was the pseudo-second order followed by the Elovich model. The SIPS model indicates a multiple adsorption mechanism, a second-order chemisorption mechanism with two main complexation bonding methods, namely, a complex with one amine functional group and a second complexing type with two amine groups and two hydroxyl groups.
Retrospective evaluation of the indications, safety and effects of fresh frozen plasma transfusions in 36 cats (2014–2018)
Authors: Mansi Elizabeth T , Waldrop Jennifer E , Davidow Elizabeth B
Published: October 2019

Objectives

The goals of this study were to classify the indications, risks, effects on coagulation times and outcomes of cats receiving fresh frozen plasma (FFP) transfusions in clinical practice.

Methods

This was a retrospective study of FFP transfusions administered in two referral hospitals from 2014 to 2018. Transfusion administration forms and medical records were reviewed. Information was collected on indication, underlying condition, coagulation times and signs of transfusion reactions. Seven-day outcomes after FFP administration were also evaluated when available.

Results

Thirty-six cats received 54 FFP transfusions. Ninety-four percent of cats were administered FFP for treatment of a coagulopathy. Twenty cats had paired coagulation testing before and after FFP administration. Eighteen of these cats had improved coagulation times after receiving 1–3 units of FFP. Eight of the 36 cats had probable transfusion reactions (14.8% of 54 FFP transfusions). These reactions included respiratory signs (n = 4), fever (n = 2) and gastrointestinal signs (n = 2). Five of the eight cats with probable reactions had received packed red blood cells contemporaneously. Overall mortality rate during hospitalization was 29.7%, with 52.8% (n = 19/36) of cats confirmed to be alive 7 days after discharge.

Conclusions and relevance

This retrospective study shows that FFP transfusions improve coagulation times in cats. Transfusion reactions are a risk, and risk–benefit ratios must be measured prior to administration and possible reactions monitored. In the study cats, the FFP transfusions appeared to be a tolerable risk given the benefit to prolonged coagulation times.
The reorganisation of a dedicated neurourology service: An interim review
Authors: Garrod Huw , Drybrough Joe , Khadr Rauf N , Floyd Michael S
Published: October 2019

Objective:

Neuropathic bladder and urinary system pathology, such as incontinence and stone formation, are the most frequently encountered complications of spinal cord injury (SCI) and neurological disease. This study assesses the patient population and current practice at a tertiary UK neurourology service following dedicated clinic restructuring in 2017.

Methods:

A retrospective database was created to assess all patients attending the neurourology clinic over an 8-month period. The database recorded patient demographics, pathologies and subsequent investigations and management. Clinical innovations such as dedicated patient questionnaires and the formation of a dedicated multidisciplinary team, and their subsequent impacts on service improvement, were also assessed.

Results:

A total of 99 patients attended the clinic during the study. The most common pathology was SCI (51.5% (51)). The most common complaints were continence and catheter issues (61.6% (61)). Urinary symptoms such as frequency (15.2% (15)), infection (13.1% (13)) and urinary tract stones (9.1% (9)) accounted for the remainder of presenting complaints. Operative intervention was required in 25.3% (25) of cases.

Conclusion:

Patients with SCI and neurological disease experience a range of urinary symptoms with significant morbidity. Ensuring upper tract integrity, safe bladder management and intervening when necessary to improve quality of life are important concerns for the neurourologist. The redesigning of a dedicated neurourology clinic has permitted the treatment of such patients with a systematic approach ensuring safe bladder monitoring and upper tract surveillance. The introduction of a validated patient-reported symptom score has helped objective monitoring of symptoms before and after specific interventions. Patient concerns regarding sexual function and fertility are increasingly being encountered and addressed in the clinic. Level of evidence: 4
Biomechanical Evaluation of a Modified Internal Brace Construct for the Treatment of Ulnar Collateral Ligament Injuries
Authors: Urch Ekaterina , Limpisvasti Orr , ElAttrache Neal S. , Itami Yasuo , McGarry Michelle H. , Photopoulos Christos D. , Lee Thay Q.
Published: October 2019

Background:

Ulnar collateral ligament (UCL) repair augmented with the “internal brace” construct for the management of acute UCL injuries has recently garnered increasing interest from the sports medicine community. One concern with this technique is excessive bone loss at the sublime tubercle, should revision UCL reconstruction be required. In an effort to preserve the bony architecture of the sublime tubercle, an alternative internal brace construct is proposed and biomechanically compared with the gold standard UCL reconstruction.

Hypothesis:

The internal brace repair construct will restore valgus laxity and rotation to its native state and demonstrate comparable load-to-failure characteristics with the 3-strand reconstruction technique.

Study Design:

Controlled laboratory study.

Methods:

For this study, 8 matched pairs of fresh-frozen cadaveric elbows were randomized to undergo either UCL reconstruction with the 3-ply docking technique or UCL repair with a novel internal brace construct focused on augmenting the posterior band of the anterior bundle of the ligament (modified repair-IB technique). Valgus laxity and rotation measurements were quantified through use of a MicroScribe 3DLX digitizer at various flexion angles of the native ligament, transected ligament, and repaired or reconstructed ligament. Laxity testing was performed from maximum extension to 120° of flexion. Each specimen was then loaded to failure, and the method of failure was recorded.

Results:

Valgus laxity was restored to the intact state at all degrees of elbow flexion with the modified repair-IB technique, and rotation was restored to the intact state at both full extension and 30°. In the reconstruction group, valgus laxity was not restored to the intact state at either full extension or 30° of flexion ( P < .001 and P = .004, respectively). Laxity was restored at 60° of flexion, but the elbow was overconstrained at 90° and 120° of flexion ( P = .027 and P = .003, respectively). In load-to-failure testing, the reconstruction group demonstrated significantly greater yield torque (19.1 vs 9.0 N·m; P < .005), yield angle (10.2° vs 5.4°; P = .007), and ultimate torque (23.9 vs 17.6 N·m; P = .039).

Conclusion:

UCL repair with posterior band internal bracing was able to restore valgus laxity and rotation to the native state. The construct exhibited lower load-to-failure characteristics when compared with the reconstruction technique.

Clinical Relevance:

In selected patients with acute, avulsion-type UCL injuries, ligament repair with posterior band internal bracing is a viable alternative surgical option that, by preserving bone at the sublime tubercle, may decrease the complexity of future revision procedures.
Technology-Aided Interventions for Individuals With Autism: Implications for Policy and Practice
Authors: Pham Andy V. , Bennett Kyle D. , Zetina Heidy
Published: October 2019

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by pervasive difficulties in reciprocal social-communication skills and restricted, repetitive interests and behaviors. Advances in assistive technology can potentially improve the functional capabilities of individuals with ASD. This article reviews current legislation and professional standards related to educating students with ASD with an emphasis on technology and evidence-based practices. In particular, the article summarizes technology-aided interventions (e.g., speech-generating devices, computer-assisted instruction, video-based instruction, virtual reality, and robot-mediated interventions) that focused on social-communication skills among individuals with ASD. Implications and future directions of technology-aided interventions are discussed.
Scoring Repeated Standardized Tests to Estimate Capacity, Not Just Current Ability
Authors: McNeish Daniel , Dumas Denis G.
Published: October 2019

Changes to educational policies have proliferated testing data to include multiple-administration assessments that repeatedly measure student performance over time. Psychometric models—extended for this type of data—estimate quantities typically associated with assessments that are given once, such as ability at a specific time point. This article considers how multiple-administration assessment offers the opportunity for models to estimate novel quantities that are not available from traditional single-administration assessments but may be of interest to educational researchers and stakeholders. Specifically, dynamic measurement models can directly estimate capacity—the expected future score once the construct of interest has fully developed. Preliminary evidence for this approach shows it may be less susceptible to effects of socioeconomic status and may improve predictions of future performance. An example with real-life operational assessment data is provided. Extensions and limitations for educational assessment are also discussed.
What Should Be the Role of Social Media in Education?
Authors: Greenhow Christine , Galvin Sarah M. , Staudt Willet K. Bret
Published: October 2019

Social media provide new opportunities for when, how, where, and with whom people learn—venue unimaginable 15 years ago. Today’s students and educators have adopted social media for various purposes both within education and outside of it. This review of the published research on social media in education focuses on the affordances for student learning, teacher professional development, educational research practices, and communication of scholarship. The article concludes with implications for education policy.
Genomic relatedness and diversity of Swedish native cattle breeds
Authors: Upadhyay Maulik , Eriksson Susanne , Mikko Sofia , Strandberg Erling , Stålhammar Hans , Groenen Martien A. M. , Crooijmans Richard P. M. A. , Andersson Göran , Johansson Anna M.
Published: October 2019

Background

Native cattle breeds are important genetic resources given their adaptation to the local environment in which they are bred. However, the widespread use of commercial cattle breeds has resulted in a marked reduction in population size of several native cattle breeds worldwide. Therefore, conservation management of native cattle breeds requires urgent attention to avoid their extinction. To this end, we genotyped nine Swedish native cattle breeds with genome-wide 150 K single nucleotide polymorphisms (SNPs) to investigate the level of genetic diversity and relatedness between these breeds.

Results

We used various SNP-based approaches on this dataset to connect the demographic history with the genetic diversity and population structure of these Swedish cattle breeds. Our results suggest that the Väne and Ringamåla breeds originating from southern Sweden have experienced population isolation and have a low genetic diversity, whereas the Fjäll breed has a large founder population and a relatively high genetic diversity. Based on the shared ancestry and the constructed phylogenetic trees, we identified two major clusters in Swedish native cattle. In the first cluster, which includes Swedish mountain cattle breeds, there was little differentiation among the Fjäll, Fjällnära, Swedish Polled, and Bohus Polled breeds. The second cluster consists of breeds from southern Sweden: Väne, Ringamåla and Swedish Red. Interestingly, we also identified sub-structuring in the Fjällnära breed, which indicates different breeding practices on the farms that maintain this breed.

Conclusions

This study represents the first comprehensive genome-wide analysis of the genetic relatedness and diversity in Swedish native cattle breeds. Our results show that different demographic patterns such as genetic isolation and cross-breeding have shaped the genomic diversity of Swedish native cattle breeds and that the Swedish mountain breeds have retained their authentic distinct gene pool without significant contribution from any of the other European cattle breeds that were included in this study.
Pimping: a tradition of gendered disempowerment
Authors: Chen David R. , Priest Kelsey C.
Published: October 2019

The use of pimping as a method of teaching is widespread in the clinical phase of medical education. In this paper we consider pimping’s colloquial meanings and discuss how it was introduced into the language of medical education. We posit that such language reflects persistent gendered hierarchies in medicine, and we evaluate pimping’s pedagogical value. Finally, we call for an end to the term and the practice, and for a renewed emphasis on pedagogy in medical education.
DNA recovery from archived RDTs for genetic characterization of Plasmodium falciparum in a routine setting in Lambaréné, Gabon
Authors: Nguyen The Trong , Nzigou Mombo Brice , Lalremruata Albert , Koehne Erik , Zoleko Manego Rella , Dimessa Mbadinga Lia Betty , Adegnika Ayola Akim , Agnandji Selidji Todagbe , Lell Bertrand , Kremsner Peter Gottfried , Velavan Thirumalaisamy P , Ramharter Michael , Mordmüller Benjamin , Mombo-Ngoma Ghyslain
Published: October 2019

Background

Rapid diagnostic tests (RDTs) have been described as a source of genetic material to analyse malaria parasites in proof-of-concept studies. The increasing use of RDTs (e.g., in focal or mass screening and treatment campaigns) makes this approach particularly attractive for large-scale investigations of parasite populations. In this study, the complexity of Plasmodium falciparum infections, parasite load and chloroquine resistance transporter gene mutations were investigated in DNA samples extracted from positive RDTs, obtained in a routine setting and archived at ambient temperature.

Methods

A total of 669 archived RDTs collected from malaria cases in urban, semi-urban and rural areas of central Gabon were used for P. falciparum DNA extraction. Performance of RDTs as a source of DNA for PCR was determined using: (i) amplification of a single copy merozoite surface protein 1 (msp1) gene followed by highly sensitive and automated capillary electrophoresis; (ii) genotyping of the pfcrt gene locus 72–76 using haplotype-specific-probe-based real-time PCR to characterize chloroquine resistance; and, (iii) real-time PCR targeting 18S genes to detect and quantify Plasmodium parasites.

Results

Out of the 669 archived RDTs, amplification of P. falciparum nucleic materials had a success rate of 97% for 18S real-time PCR, and 88% for the msp1 gene. The multiplicity of infections (MOI) of the whole population was 2.6 (95% CI 2.5–2.8). The highest number of alleles detected in one infection was 11. The MOI decreased with increasing age (β = − 0.0046, p = 0.02) and residence in Lambaréné was associated with smaller MOIs (p < 0.001). The overall prevalence of mutations associated with chloroquine resistance was 78.5% and was not associated with age. In Lambaréné, prevalence of chloroquine resistance was lower compared to rural Moyen-Ogooué (β = − 0.809, p-value = 0.011).

Conclusion

RDT is a reliable source of DNA for P. falciparum detection and genotyping assays. Furthermore, the increasing use of RDTs allows them to be an alternative source of DNA for large-scale genetic epidemiological studies. Parasite populations in the study area are highly diverse and prevalence of chloroquine-resistant P. falciparum remains high, especially in rural areas.
Heparinized silk fibroin hydrogels loading FGF1 promote the wound healing in rats with full-thickness skin excision
Authors: He Sirong , Shi Dan , Han Zhigang , Dong Zhaoming , Xie Yajun , Zhang Fengmei , Zeng WenXin , Yi Qiying
Published: October 2019

Background

Silk fibroin hydrogel, derived from Bombyx mori cocoons, has been shown to have potential effects on wound healing due to its excellent biocompatibility and less immunogenic and biodegradable properties. Many studies suggest silk fibroin as a promising material of wound dressing and it can support the adhesion and proliferation of a variety of human cells in vitro. However, lack of translational evidence has hampered its clinical applications for skin repair. Herein, a heparin-immobilized fibroin hydrogel was fabricated to deliver FGF1 (human acidic fibroblast growth factor 1) on top of wound in rats with full-thickness skin excision by performing comprehensive preclinical studies to fully evaluate its safety and effectiveness. The wound-healing efficiency of developed fibroin hydrogels was evaluated in full-thickness wound model of rats, compared with the chitosan used clinically.

Results

The water absorption, swelling ratio, accumulative FGF1 releasing rate and biodegradation ratio of fabricated hydrogels were measured. The regenerated fibroin hydrogels with good water uptake properties rapidly swelled to a 17.3-fold maximum swelling behavior over 12 h and a total amount of 40.48 ± 1.28% hydrogels was lost within 15 days. Furthermore, accumulative releasing data suggested that heparinized hydrogels possessed effective release behavior of FGF1. Then full-thickness skin excision was created in rats and left untreated or covered with heparinized fibroin hydrogels-immobilized recombinant human FGF1. The histological evaluation using hematoxylin and eosin (HE) and Masson’s trichrome (MT) staining was performed to observe the dermic formation and collagen deposition on the wound-healing site. To evaluate the wound-healing mechanisms induced by fibroin hydrogel treatment, wound-healing scratch and cell proliferation assay were performed. it was found that both fibroin hydrogels and FGF1 can facilitate the migration of fibroblast L929 cells proliferation and migration.

Conclusion

This study provides systematic preclinical evidence that the silk fibroin promotes wound healing as a wound-healing dressing, thereby establishing a foundation toward its further application for new treatment options of wound repair and regeneration.
Sylvatic cycles of arboviruses in non-human primates
Authors: Valentine Matthew John , Murdock Courtney Cuin , Kelly Patrick John
Published: October 2019

Arboviruses infecting people primarily exist in urban transmission cycles involving urban mosquitoes in densely populated tropical regions. For dengue, chikungunya, Zika and yellow fever viruses, sylvatic (forest) transmission cycles also exist in some regions and involve non-human primates and forest-dwelling mosquitoes. Here we review the investigation methods and available data on sylvatic cycles involving non-human primates and dengue, chikungunya, Zika and yellow fever viruses in Africa, dengue viruses in Asia and yellow fever virus in the Americas. We also present current putative data that Mayaro, o’nyong’nyong, Oropouche, Spondweni and Lumbo viruses exist in sylvatic cycles.
A comparative assessment of adult mosquito trapping methods to estimate spatial patterns of abundance and community composition in southern Africa
Authors: Gorsich Erin E. , Beechler Brianna R. , van Bodegom Peter M. , Govender Danny , Guarido Milehna M. , Venter Marietjie , Schrama Maarten
Published: October 2019

Background

Assessing adult mosquito populations is an important component of disease surveillance programs and ecosystem health assessments. Inference from adult trapping datasets involves comparing populations across space and time, but comparisons based on different trapping methods may be biased if traps have different efficiencies or sample different subsets of the mosquito community.

Methods

We compared four widely-used trapping methods for adult mosquito data collection in Kruger National Park (KNP), South Africa: Centers for Disease Control miniature light trap (CDC), Biogents Sentinel trap (BG), Biogents gravid Aedes trap (GAT) and a net trap. We quantified how trap choice and sampling effort influence inferences on the regional distribution of mosquito abundance, richness and community composition.

Results

The CDC and net traps together collected 96% (47% and 49% individually) of the 955 female mosquitoes sampled and 100% (85% and 78% individually) of the 40 species or species complexes identified. The CDC and net trap also identified similar regional patterns of community composition. However, inference on the regional patterns of abundance differed between these traps because mosquito abundance in the net trap was influenced by variation in weather conditions. The BG and GAT traps collected significantly fewer mosquitoes, limiting regional comparisons of abundance and community composition.

Conclusions

This study represents the first systematic assessment of trapping methods in natural savanna ecosystems in southern Africa. We recommend the CDC trap or the net trap for future monitoring and surveillance programs.
Whatever happened to China’s neglected tropical diseases?
Authors: Hotez Peter J.
Published: October 2019

Before the founding of the People’s Republic of China 70 years ago, both extreme poverty and parasitic infections and other neglected tropical diseases were highly prevalent. Owing to social development, particularly economic reforms since the 1980s, poverty has since been dramatically reduced, and China became increasingly urbanized and industrialized. In parallel, China’s economic transformation translated into similar and remarkable reductions in neglected tropical diseases. Qian and colleagues report in their review published in Infectious Diseases of Poverty, the elimination or near elimination as a public health problem of lymphatic filariasis, trachoma, soil-transmitted helminth infections, schistosomiasis and other neglected tropical diseases. Of note, neglected tropical disease control and poverty reduction each appear to reinforce the other. China’s formula for success in parasitic and neglected tropical disease control might translate to other parts of the world, such as in sub-Saharan Africa through China’s new Belt and Road Initiative.
Technical feasibility of constant-load and high-intensity interval training for cardiopulmonary conditioning using a re-engineered dynamic leg press
Authors: Chrif Farouk , Nef Tobias , Hunt Kenneth J
Published: October 2019

Background

Leg-press devices are one of the most widely used training tools for musculoskeletal strengthening of the lower-limbs, and have demonstrated important cardiopulmonary benefits for healthy and patient populations. Further engineering development was done on a dynamic leg-press for work-rate estimation by integrating force and motion sensors, power calculation and a visual feedback system for volitional work-rate control. This study aimed to assess the feasibility of the enhanced dynamic leg press for cardiopulmonary exercise training in constant-load training and high-intensity interval training. Five healthy participants aged 31.0±3.9 years (mean ± standard deviation) performed two cardiopulmonary training sessions: constant-load training and high-intensity interval training. Participants carried out the training sessions at a work rate that corresponds to their first ventilatory threshold for constant-load training, and their second ventilatory threshold for high-intensity interval training.

Results

All participants tolerated both training protocols, and could complete the training sessions with no complications. Substantial cardiopulmonary responses were observed. The difference between mean oxygen uptake and target oxygen uptake was 0.07±0.34 L/min (103 ±17%) during constant-load training, and 0.35±0.66 L/min (113 ±27%) during high-intensity interval training. The difference between mean heart rate and target heart rate was −7±19 bpm (94 ±15%) during constant-load training, and 4.2±16 bpm (103 ±12%) during high-intensity interval training.

Conclusions

The enhanced dynamic leg press was found to be feasible for cardiopulmonary exercise training, and for exercise prescription for different training programmes based on the ventilatory thresholds.
Application of facies-based rock-physics inversion in the appraisal of the Cragganmore gas discovery, West of Shetland
Authors: Purcell Chris , Hoyes Jack
Published: October 2019

Facies-based rock-physics inversion is a tool that is generally employed in data-rich areas. It also can be useful in areas with little well control. This method was used to investigate the Cragganmore discovery in the West of Shetland in the United Kingdom. By utilizing wells outside of the seismic data set, a better-informed inversion can be created that can assist in future appraisal programs.
Digital superresolution in seismic AVO inversion
Authors: Kolbj⊘rnsen Odd , Kjelsrud Evensen Andreas , Nilsen Espen Harris , Lie Jan Erik
Published: October 2019

The sparseness promoted by the total variation norm is utilized to achieve superresolution amplitude-variation-with-offset (AVO) inversion. The total variation norm promotes solutions that have constant values within unspecified regions and thus are well suited for an earth model consisting of layers bounded by faults and erosion surfaces. Algorithmic developments from digital image and video restoration are utilized to solve the geophysical problem. A spatial point spread function is used to model the resulting effect of wave propagation, migration, and processing. The methodology is compared to current alternatives and discussed in the context of AVO inversion. Good results are obtained in a Barents Sea test case.
Unilateral Lung Recruitment Maneuver for Massive Atelectasis in a Child With Glenn Circulation: A Case Report
Authors: Kimura Yoshikazu , Kanazawa Tomoyuki , Kuroe Yasutoshi , Tani Makiko , Shimizu Kazuyoshi , Iwasaki Tatsuo , Morimatsu Hiroshi
Published: October 2019

A 9-year-old girl with Glenn circulation suffered from massive atelectasis of the left lung caused by bleeding during cardiac catheterization. The atelectasis resulted in frequent hypoxia leading to oxygen saturation (Spo
2) of 40%–50%. In the intensive care unit, we performed a unilateral lung recruitment maneuver (ULRM) for 2 days. The ULRM involved placement of a bronchial blocker in the right main bronchus and application of continuous positive airway pressure to the left lung without hemodynamic deterioration. Eventually, Spo
2 improved to 80%–85%. ULRM can be a treatment option for unilateral atelectasis in a child with Glenn circulation.
Transporting cells over several days without dry-ice
Authors: Wheatley Sally P. , Wheatley Denys N.
Published: October 2019

This paper describes a simple, hazard-free and inexpensive procedure that allows researchers to send cultured cells across the globe at ambient temperatures. The method enables transit of up to 2 weeks without compromising cell recovery. Its use will assist collaborators in distant laboratories to exchange cells without using dry-ice.
Governança Corporativa e Velocidade de Incorporação de Informações: Lead-Lag entre o IGC e o IBrX
Authors: Oliveira Neto José Carneiro da Cunha , Medeiros Otávio Ribeiro de , Queiroz Thiago Bergmann de
Published: October 2019

Com base em dados intradiários em frequência de 15 minutos, o presente estudo investiga a relação entre o mercado de Governança Corporativa Diferenciada (IGC) e o Mercado Tradicional (IBrX). A hipótese testada é de que um melhor nível de Governança Corporativa reduz os custos associados à incorporação de novas informações aos preços dos ativos da empresa. Assim, empresas com melhor nível de governança teriam maior velocidade de incorporação de informações. A relação de cointegração entre as séries foi testada com o uso do método Engle-Granger, em dois estágios. O Vetor de Correção de Erros (VECM) e o teste de causalidade de Granger não permitem a rejeição da hipótese de maior velocidade de incorporação de informações do Mercado de Governança Diferenciada. Para estimativa do VECM, utilizou-se um modelo GARCH bivariado BEKK. Os resultados sugerem que o IGC encontra seu preço de equilíbrio mais rapidamente e que o IBrX converge para a relação de equilíbrio apontada pelo IGC.
Modelo Híbrido GJR-GARCH Nebuloso para a Previsão da Volatilidade em Mercados de Ações
Authors: Maciel Leandro
Published: October 2019

A previsão da volatilidade dos retornos de ativos financeiros é uma abordagem desafiadora e tem atraído a atenção de participantes do mercado, reguladores e acadêmicos nos anos recentes. Este artigo propõe um modelo GJR-GARCH nebuloso para a previsão da volatilidade dos índices S&P 500 e Ibovespa. O modelo combina os conceitos de sistemas de inferência nebulosos e a abordagem GJR-GARCH para considerar os príncipios de variância condicional, efeitos de alavancagem e agrupamentos de volatilidade, em que as flutuações são associadas por similaridade. Além disso, um algoritmo de evolução diferencial (ED) é sugerido para solucionar o problema de estimação dos parâmetros do modelo GJR-GARCH nebuloso. Os resultados indicaram que o método proposto permitiu uma melhor capacidade de previsão da volatilidade em comparação com modelos da família GARCH e com um modelo GARCH nebuloso recentemente proposto na literatura. Além disso, o algoritmo de ED considerado obteve soluções ótimas com uma rápida taxa de convergência.
Avaliando Modelos de Precificação de Ativos via Abordagem de Fatores Simulados
Authors: Carrasco-Gutierrez Carlos Enrique , Gaglianone Wagner Piazza
Published: October 2019

Neste artigo apresenta-se uma metodologia para comparar a performance relativa de diferentes modelos de fator estocástico de desconto (SDF - Stochastic Discount Factor). O ponto de partida é a estimação de modelos de fatores gerados por abordagens distintas. Em seguida, uma simulação de Monte Carlo é construída para simular um conjunto de retornos (brutos) de ativos, com o intuito de replicar a dependência temporal e respectivas covariâncias amostrais observadas em retornos de ativos. Por fim, os retornos artificiais são utilizados para investigar a performance de modelos de precificação de ativos através da distância de Hansen e Jagannathan (1997) e de algumas estatísticas de teste baseadas em erros de precificação. Um exercício empírico com dados de ativos norte-americanos é apresentado para ilustrar a metodologia proposta.
Discricionariedade na Mensuração de Derivativos como Mecanismo de Gerenciamento de Resultados em Bancos
Authors: Dantas José Alves , Galdi Fernando Caio , Capelletto Lúcio Rodrigues , Medeiros Otávio Ribeiro
Published: October 2019

O artigo tem por objetivo identificar se os bancos brasileiros são discricionários quanto às escolhas contábeis quando do reconhecimento e mensuração dos derivativos para o gerenciamento de resultados e quais são os determinantes dessa prática. Utilizando modelo de dois estágios para segregar a parcela discricionária do valor justo estimado dos derivativos e com base em informações entre o terceiro trimestre de 2002 e o quarto trimestre de 2010, os resultados empíricos confirmam a reversão da parcela discricionária em períodos subsequentes, revelam que os bancos utilizam esse tipo de ação como mecanismo para o alisamento de resultados, e evidenciam que essa prática é mais comum nas instituições privadas, com menores ativos e menor nível de capitalização. As evidências avançam em relação a estudos anteriores, que identificaram o uso de derivativos na prática do gerenciamento de resultados pelos bancos, mas não associaram essa prática à ação discricionária da administração.
Eficiência de Mercado e Desempenho de Fundos Multimercados
Authors: Malaquias Rodrigo Fernandes , Eid Junior William
Published: October 2019

De acordo com a teoria sobre a Hipótese de Eficiência de Mercado (HEM), os preços dos títulos no mercado deveriam refletir toda a informação até o ponto em que os custos de se agir com base nestas informações não superasse os benefícios proporcionados (Jensen, 1978; Fama, 1991). Nesse contexto, este trabalho teve por objetivo analisar se informações passadas e publicamente disponíveis podem ser úteis para obtenção de retornos extraordinários no segmento de fundos multimercados brasileiros, testando, assim, a HEM nessa categoria de fundos. Com dados de 831 fundos, segregados em duas amostras (551 entre Outubro/2007-Setembro/2011 e 280 entre Outubro/2009-Setembro/2011), os principais resultados apontaram que, em média, os fundos não agregam valor extraordinário. Contudo, há informações passadas e publicamente disponíveis dos fundos que estiveram relacionadas à sua performance, o que parece não estar em linha com a HEM, levando a questionamentos como: os investidores monitoram variáveis relacionadas à performance dos fundos?
Seleção de uma Carteira de Pares de Ações Usando Cointegração: Uma Estratégia de Arbitragem Estatística
Authors: Caldeira João Frois , Moura Gulherme Valle
Published: October 2019

Estratégias de arbitragem estatística como pairs trading e suas generalizações dependem da construção de spreads estacionários com certo grau de previsibilidade. Este trabalho aplica testes de cointegração para identificar ativos para serem usados em estratégias de pairs trading. Além de estimar o equilíbrio de longo prazo e de modelar os resíduos resultantes, pares de ações são selecionados baseados em um indicador de lucratividade para compor um portfólio de pares. O retorno da estratégia é avaliado com dados diários da Bovespa durante o período de janeiro de 2005 até outubro de 2012. A análise empírica mostra que a estratégia proposta obtém excessos de retorno da ordem de 16.38% ao ano, índice de Sharpe de 1.34 e baixa correlação com o Ibovespa.
O que motiva a realização de intervenções cambiais? Análise das atuações do Banco Central do Brasil no mercado BRL/USD
Authors: Teixeira Felipe Wolk , Meurer Roberto , Santos André Alves Portela
Published: October 2019

Neste artigo analisamos os determinantes da probabilidade de intervenção de compra e venda por parte do Banco Central do Brasil (BCB) no mercado a vista de dólar durante o período de 1999 a 2010. Os resultados indicam que a probabilidade de intervenção é função dos níveis de retorno cambial, do spread entre juros doméstico e internacional e da volatilidade do câmbio. Além disso, as intervenções passadas também desempenham papel ativo na formação da intervenção contemporânea. A possibilidade de maior presença no mercado mediante determinados condicionantes sugere a existência tanto de coordenação entre política externa e monetária efetuada pelo BCB, compatível com uma política econômica de duas metas e dois instrumentos, como uma possível sinalização de existência de uma banda cambial informal.
Determinantes de adesão ao Índice de Sustentabilidade Empresarial da BM&FBOVESPA e sua relação com o valor da empresa
Authors: Andrade Lélis Pedro , Bressan Aureliano Angel , Iquiapaza Robert Aldo , Moreira Bruno César de Melo
Published: October 2019

Este artigo foi realizado com o objetivo de identificar variáveis que se apresentam como determinantes de adesão de empresas brasileiras ao Índice de Sustentabilidade Empresarial (ISE) da BM&FBOVESPA, e se tal adesão apresenta relação com o valor de mercado das empresas. Foram coletados dados anuais das empresas, no período de 2006 a 2011. A metodologia compreendeu a aplicação de diferentes métodos, tais como a análise de regressões do tipo logit e de dados em painel. Os resultados obtidos demonstraram que as empresas que têm maior tamanho, maior rentabilidade e são de setores considerados de alto impacto ambiental, possuem maior probabilidade de aderirem ao ISE. Quando se analisou se a adesão ao ISE possui relação com as métricas de valor da empresa, os resultados não rejeitaram a hipótese de relação positiva, porém, foram encontrados indícios de relação negativa no período pós-crise financeira de 2008.
Políticas de Cash Holdings: uma Abordagem Dinâmica das Empresas Brasileiras
Authors: Dahrouge Fadwa Muhieddine , Saito Richard
Published: October 2019

Esse artigo investiga como as empresas brasileiras ajustaram o nível de cash holdings durante o período da crise 2008-2009. Utilizamos um modelo dinâmico de caixa para avaliar os principais determinantes da velocidade de ajuste do nível de cash holdings para o nível ótimo. Encontramos evidências que: a) o comportamento dinâmico de caixa é significativo e os custos de ajustes das empresas brasileiras são altos, impedindo o ajuste imediato para o nível ótimo; b) a baixa velocidade de ajuste ao nível ótimo é decorrente da pouca disponibilidade e do alto custo de financiamento; c) durante a crise, o capital de giro é positivamente relacionado ao nível de cash holdings, indicando que as empresas financiaram crescimento com base em liquidez e vice-versa, d) consequentemente os resultados apontam uma relação negativa entre investimentos e cash holdings, pois as empresas utilizam dívida de longo prazo para retenção de caixa, privilegiando a manutenção da liquidez.