bluuebunny/crossref_metadata_2025 huggingface dataset:
Cortisol reactivity and weight gain among adolescents who vary in prenatal drug exposure
Authors: Armstrong B. , Buckingham‐Howes S. , Black M. M.
Published: August 2018

Objective

Low inhibitory control is linked with weight gain among youth. Inhibitory problems are associated with disruption to the hypothalamic–pituitary–adrenal axis cortisol response. Increased cortisol predicts appetite and weight gain (though may be gender specific). This study hypothesized that cortisol reactivity explains the association between inhibition and weight gain while considering the moderating factors of early stressors to the hypothalamic–pituitary–adrenal axis (e.g. prenatal‐drug exposure) and gender.

Methods

Adolescents with prenatal‐drug exposure (n = 76) and non‐exposed comparison adolescents (NE; n = 61) completed the Conner's Continuous Performance Test and provided salivary cortisol samples. BMI z‐score were measured at the initial and 12‐month follow‐up evaluations. A bootstrapped moderated mediation analysis was conducted to test for conditional indirect effects of cortisol reactivity.

Results

Lower inhibition was associated with increased cortisol reactivity among youth who were NE, and increased cortisol reactivity was associated with weight gain among girls. Cortisol reactivity mediated the relation between inhibition and BMI z‐score change for the girls in the group who was NE.

Conclusion

Increased cortisol reactivity may play a mechanistic role in predicting weight gain among non‐prenatally drug‐exposed girls. Cortisol reactivity may be a biomarker for targeted interventions to improve biological regulation and ultimately health risk among girls.
The fear of needles: A systematic review and meta‐analysis
Authors: McLenon Jennifer , Rogers Mary A.M.
Published: August 2018

Aims

The aim of this study was to evaluate the prevalence of needle fear and summarize the characteristics of individuals who exhibit this fear.

Background

Injections are among the most common medical procedures, yet fear of needles can result in avoidance of preventive measures and treatment.

Design

Systematic review and meta‐analysis.

Data Sources

MEDLINE (1966–2017), Embase (1947–2017), PsycINFO (1967–2017), and CINAHL (1961–2017) were searched, with no restrictions by age, gender, race, language, or country.

Review Methods

The prevalence of needle fear was calculated and restricted maximum likelihood random effects models were used for meta‐analysis and meta‐regression.

Results

The search yielded 119 original research articles which are included in this review, of which 35 contained sufficient information for meta‐analysis. The majority of children exhibited needle fear, while prevalence estimates for needle fear ranged from 20‐50% in adolescents and 20–30% in young adults. In general, needle fear decreased with increasing age. Both needle fear and needle phobia were more prevalent in females than males. Avoidance of influenza vaccination because of needle fear occurred in 16% of adult patients, 27% of hospital employees, 18% of workers at long‐term care facilities, and 8% of healthcare workers at hospitals. Needle fear was common when undergoing venipuncture, blood donation, and in those with chronic conditions requiring injection.

Conclusions

Fear of needles is common in patients requiring preventive care and in those undergoing treatment. Greater attention should be directed to interventions which alleviate fear in high‐risk groups.
A simple method to estimate the thermal diffusivity of foods
Authors: Mari João , Mari Marcus , Ferreira Maykon , Conceição Wagner , Andrade Cid
Published: August 2018

This work shows an alternative method to determine the thermal diffusivity of wheat flour and cassava, by means of experiments. It was considered as a model for analysis a semi‐infinite solid, represented by an aluminum container filled with flour, an incandescent lamp as a heat source and thermocouple sensors for acquisition of electronic temperature signal. From the moment in which the temperature on the upper surface of flour remained constant, the data were acquired at a predefined time interval, which allowed obtaining the thermal diffusivity. To evaluate the results achieved from the experiments, it was carried out a simulation in Partial Differential Equation Toolbox of Matlab R2015a, in order to compare the temperature distributions within the solid. It was verified that the values showed by simulation are satisfactorily close to the experimental values.

Practical applications

Some information about physical properties of foods usually are not available, therefore, a simple method to estimate the thermal diffusivity could be useful, once it influences the quality control of foods. Thus, the findings of this study may facilitate the food industry, assisting the design, and simulation of process, such as heating, cooling, freezing, defrosting, frying, and storage.
Effect of a prebiotic galactooligosaccharide mixture (B‐GOS®) on gastrointestinal symptoms in adults selected from a general population who suffer with bloating, abdominal pain, or flatulence
Authors: Vulevic Jelena , Tzortzis George , Juric Aleksandra , Gibson Glenn R.
Published: August 2018

Background

Prebiotics exert beneficial effects upon gastrointestinal (GI) environment, but this is not always accompanied with a positive effect on GI symptoms. B‐GOS® is a prebiotic with high selectivity toward bifidobacteria and a variety of other beneficial effects in humans. Here, we investigated its effect on GI symptoms in adults who suffer with bloating, abdominal pain, and flatulence.

Methods

In a double‐blind, placebo‐controlled, crossover study, 83 subjects from the general population who presented with GI symptoms during screening period and had a predicted probability of functional bowel disorder of more than 75% were randomized to receive either a placebo or the B‐GOS® treatment (2.75 g/d). Subjects were screened for the presence of GI symptoms for 1 week, they consumed the treatments for 2 weeks, and then went through a 2‐week washout period, before switching to the other treatment for the final 2 weeks. GI symptoms, bowel movements, and stool consistency were assessed in daily and weekly questionnaires. Quality of life was assessed weekly and depression and anxiety at the end of each treatment period.

Results

B‐GOS® resulted in significantly (P < 0.001) lower scores for bloating, flatulence, and abdominal pain both from baseline and placebo at the end of first week. The effect was sustained at the end of second week. It had no effect on the number of bowel movements, consistency of stools, quality of life, or mood throughout the study.

Conclusion

Results suggest that B‐GOS® could possibly be used in the management of bloating, flatulence, or abdominal pain and warrant further investigation.
Exploring pyloric dynamics in stenting using a distensibility technique
Authors: Arroyo Vázquez Jorge Alberto , Bergström Maria , Bligh Stephen , McMahon Barry P. , Park Per‐Ola
Published: August 2018

Background

Perforated duodenal ulcers can be treated with a covered stent. Stent migration is a severe complication, sometimes requiring surgery. Pyloric physiology during stent treatment has not been studied and mechanisms for migration are unknown. The aim of this study was to investigate the pyloric response to distention, mimicking stent treatment, using the EndoFLIP.

Methods

A nonsurvival study in five pigs was carried out, followed by a pilot study in one volunteer. Animals were gastroscoped during anaesthesia and the EndoFLIP was placed straddling the pylorus. Baseline distensibility readings were performed at stepwise balloon distentions to 20, 30, 40, and 50 mL, measuring pyloric cross‐sectional area and pressure. Measurements were repeated after administration of a prokinetic drug and after a liquid meal. In the human study, readings were performed in conscious sedation at baseline and after stimulation with metoclopramide.

Key Results

During baseline readings, the pylorus was shown to open more with increasing distention together with higher amplitude motility waves. Reaching maximum distention‐volume (50 mL), pyloric pressure increased significantly (P = 0.016), and motility waves disappeared. After prokinetic stimulation, the pressure decreased and the motility waves increased in frequency and amplitude. After food stimulation, the pressure stayed low and the motility showed increase in amplitude. During both tests, the pylorus showed higher pressure and lack of motility waves at maximum probe distention.

Conclusions and Inferences

The pylorus seems to act as a sphincter at low distention but when further dilated starts acting as a pump. Fully distended the pyloric motility disappears and the pressure remains high, suggesting that a stent with high‐radial force might show less migration.
Corneal collagen cross‐linking following superficial keratectomy as treatment for corneal endothelial cell dystrophy in dogs: Preliminary clinical study
Authors: Kim Jury , Ji Dong‐Beom , Takiyama Naoaki , Bae Jaehyun , Kim Min‐Su
Published: August 2018

Objective

To describe the outcome of corneal collagen cross‐linking (CXL) combined with superficial keratectomy (SK) as treatment for corneal edema due to corneal endothelial dystrophy (CED) in dogs.

Animals studied

Four eyes of four dogs (3 Shih Tzus and 1 English Cocker Spaniel) with corneal edema due to CED were treated with SK and CXL. Two were males, and two were females.

Procedure

Depending on corneal thickness, 500‐700 μm of edematous cornea was removed by SK. Next, CXL was performed by irradiating the cornea with UVA (365 nm) at 3 mW/cm² irradiance for 30 min after soaking with 0.1% riboflavin in 20% dextran every three minutes for 30 minutes. One drop of riboflavin was instilled every three minutes during irradiation. Slit lamp biomicroscopy and optical coherence tomography were used to examine the cornea during the follow‐up period.

Results

The corneas had focal to diffuse edema, and the average corneal thickness was 1553 (1282‐1900) μm. All corneas showed a significantly reduced corneal thickness and regained marked transparency immediately after treatment; however, the opacity increased as the corneal thickness increased during the follow‐up period. Corneal vascularization (n = 4) disappeared within a month. Corneal pigmentation (n = 1) and bullae (n = 1) were observed. All cases showed marked reduction in corneal thickness; however, transparency was improved in only one case.

Conclusion

Collagen cross‐linking with SK has the potential to reduce the corneal thickness in CED cases; however, a lasting clinically significant improvement of corneal transparency seems unlikely. As the added benefit of CXL to the SK procedure is unclear based on the results of this study, combined treatment of CXL and SK for the treatment of corneal edema caused by CED is currently not recommended in dogs.
Views of Primary Teachers About Homework (A Qualitative Analysis)
Authors: Buyukalan Sevil Filiz , Altinay Yasemin Boyaci
Published: August 2018

The aim of this study is to reveal the views of classroom teachers about homework assigned to primary students. In the study, a qualitative method was employed. The data were collected through semi-structured interviews and the participants were chosen using the purposive sampling technique. The participants of this study are twenty classroom teachers who taught the primary grades of 1, 2, 3 and 4 at a public primary school in Konya during the school year of 2017-2018. The interview form was administered to four classroom teachers in a pilot study whose findings produced a reliability level of 88% and the obtained data were analysed using the descriptive statistics. The participants’ answers to the interview items were categorized under common themes and sub-themes. Besides, in the discussion of the findings direct quotations were also given. The findings generally indicate that the teachers had a positive attitude towards homework assignments. It was also found that for them homework assignments contribute positively to increase student achievement. The findings also suggest that the views of the participants about homework assignments do not vary based on the variables of gender, grade level, their professional experience and their educational background.
Importance of Assessment in ELT
Authors: Tosuncuoglu Irfan
Published: August 2018

Assessment has an important role in education and it has a critical role in the teaching process. Through appropriate assessment, teachers can classify and grade their students, give feedback and structure their teaching accordingly. Recently, educators and scientists have been becoming more interested in the requirements of assessment procedures in the scope of foreign language teaching and the learning process, as forms of assessment have been changing. The assessment procedures relate to authenticity, practicality, reliability, validity and wash back, and are considered the basic principles of assessment in foreign language teaching and learning. The main value of these aforementioned principles is to distinguish the effects of assessment and review any classroom based issues between the teacher and the student. As the assessment process affects both teachers and students, significance and consideration should be given to assessment procedures in foreign language teaching.
Sensorineural hearing loss impairs sensitivity but spares temporal integration for detection of frequency modulation
Authors: Wallaert Nicolas , Varnet Léo , Moore Brian C. J. , Lorenzi Christian
Published: August 2018

The effect of the number of modulation cycles (N) on frequency-modulation (FM) detection thresholds (FMDTs) was measured with and without interfering amplitude modulation (AM) for hearing-impaired (HI) listeners, using a 500-Hz sinusoidal carrier and FM rates of 2 and 20 Hz. The data were compared with FMDTs for normal-hearing (NH) listeners and AM detection thresholds (AMDTs) for NH and HI listeners [Wallaert, Moore, and Lorenzi (2016). J. Acoust. Soc. 139, 3088–3096; Wallaert, Moore, Ewert, and Lorenzi (2017). J. Acoust. Soc. 141, 971–980]. FMDTs were higher for HI than for NH listeners, but the effect of increasing N was similar across groups. In contrast, AMDTs were lower and the effect of increasing N was greater for HI listeners than for NH listeners. A model of temporal-envelope processing based on a modulation filter-bank and a template-matching decision strategy accounted better for the FMDTs at 20 Hz than at 2 Hz for young NH listeners and predicted greater temporal integration of FM than observed for all groups. These results suggest that different mechanisms underlie AM and FM detection at low rates and that hearing loss impairs FM-detection mechanisms, but preserves the memory and decision processes responsible for temporal integration of FM.
Auditory sensitivity, spatial dynamics, and amplitude of courtship song in Drosophila melanogaster
Authors: Morley Erica L. , Jonsson Thorin , Robert Daniel
Published: August 2018

Acoustic communication is an important component of courtship in Drosophila melanogaster. It takes the form of courtship song produced by males through the unilateral extension and vibration of a wing. Following the paradigm of sender–receiver matching, song content is assumed to match tuning in the auditory system, however, D. melanogaster audition is nonlinear and tuning dependent upon signal amplitude. At low stimulus amplitudes or in the absence of sound the antenna is tuned into song frequency, but as amplitude increases the antenna's resonance is shifted up by hundreds of Hertz. Accurate measurements of song amplitude have been elusive because of the strong dependency of amplitude upon the spatial geometry between sender and receiver. Here, D. melanogaster auditory directional sensitivity and the geometric position between the courting flies are quantified. It is shown that singing occurs primarily from positions resulting in direct stimulation of the female antenna. Using this information, it is established that the majority of song is louder than theoretically predicted and at these sound levels the female antenna should not amplify or be tuned into song. The study implies that Drosophila hearing, and, in particular, its active mechanisms, could function in a broader context than previously surmised.
Molecular signatures and functional analysis of beige adipocytes induced from in vivo intra-abdominal adipocytes
Authors: Xue Huiling , Wang Zhe , Hua Yongjie , Ke Shanshan , Wang Yao , Zhang Junpeng , Pan Yi-Hsuan , Huang Wenjie , Irwin David M. , Zhang Shuyi
Published: August 2018

Bat and mouse beige adipocytes induced from white adipocytes provide insights into therapy against obesity-related disease.
Fake legal logging in the Brazilian Amazon
Authors: Brancalion Pedro H. S. , de Almeida Danilo R. A. , Vidal Edson , Molin Paulo G. , Sontag Vanessa E. , Souza Saulo E. X. F. , Schulze Mark D.
Published: August 2018

Weak control and monitoring of logging permits put the most commercially valuable Amazonian tree species at risk in Brazil.
Building an evidence base for stakeholder engagement
Authors: Lavery James V.
Published: August 2018

The private sector provides lessons and models
Turn it up
When the Uncertainty Principle Goes to 11
Philip Moriarty
BenBella Books, 2018. 350 pp.
Authors: Reilly David J.
Published: August 2018

Science meets metal in a musical introduction to modern physics
Health of the Hajj
Authors: Memish Ziad A.
Published: August 2018

For 5 days, starting 19 August, Saudi Arabia will host the Hajj, the world's largest annual religious pilgrimage, where people from over 180 countries will converge on Mecca. Infectious disease transmission associated with this mass transnational movement of people is well known—malaria in 632 CE, meningitis in 1987 and 2000, polio in 2004, and pandemic influenza in 2009. As the former Deputy Minister of Public Health for Saudi Arabia, I know how immense the challenge is to ensure that the country is prepared to contain the spread of infectious disease and maintain public well-being during this event. Although major progress has been made over the past 30 years in Saudi Arabia and in pilgrimage countries, there is still much more to do to avoid a health catastrophe, given that the pilgrim quota may grow to 2.2 million by 2020.
Not as bad as it seems: When the presence of a threatening humanoid robot improves human performance
Authors: Spatola Nicolas , Belletier Clément , Normand Alice , Chausse Pierre , Monceau Sophie , Augustinova Maria , Barra Vincent , Huguet Pascal , Ferrand Ludovic
Published: August 2018

“Bad” humanoid robots paying attention to human performance energized attentional control—as does human presence.
KHS101 disrupts energy metabolism in human glioblastoma cells and reduces tumor growth in mice
Authors: Polson Euan S. , Kuchler Verena B. , Abbosh Christopher , Ross Edith M. , Mathew Ryan K. , Beard Hester A. , da Silva Bárbara , Holding Andrew N. , Ballereau Stephane , Chuntharpursat-Bon Eulashini , Williams Jennifer , Griffiths Hollie B.S. , Shao Hao , Patel Anjana , Davies Adam J. , Droop Alastair , Chumas Paul , Short Susan C. , Lorger Mihaela , Gestwicki Jason E. , Roberts Lee D. , Bon Robin S. , Allison Simon J. , Zhu Shoutian , Markowetz Florian , Wurdak Heiko
Published: August 2018

Modulation of energy metabolism with the small-molecule KHS101 promoted tumor-selective death of human glioblastoma cells and reduced tumor growth in mice.
Radiation reaction in a Lorentz-violating modified Maxwell theory
Authors: Reddy V. Veera , Gutti S. , Haque A.
Published: August 2018

We study the radiation reaction in Lorentz-violating electrodynamics [D. Colladay and V. Alan Kostelecky, Phys. Rev. D 58, 116002 (1998)]. We explore the possible modification whatsoever present in the radiation reaction force experienced by an accelerating charge in the modified Maxwell theory. However, it turns out that radiation reaction receives no change due to Lorentz violation, whereas electromagnetic mass manifests anisotropy.
Shape-dependent black hole quantum spectrum
Authors: Sepehri Alireza , Shoorvazi Somayeh
Published: August 2018

Recently, the quantum spectrum of black holes has been considered. We will show that this spectrum depends on the shape of manifolds that form black holes. For example, black holes with heptagonal shapes have more energy and less temperature with respect to the ones with pentagonal or hexagonal shapes.
Rapid generation of perfect vortex beam without side lobes
Authors: Li Siqi , Liu Mulong , Li Xingyi , Ge Zhiqiang , Zhang Lingxuan
Published: August 2018

We have proposed an approach for rapid generation of perfect vortex beam without side lobes through a digital micromirror device (DMD). Employing this method, the amplitude and phase of far field can be controlled indirectly by changing the rotation state of each unit on the DMD. The perfect vortex beams of equal rings diameter independent of their topological charges are generated commendably and the side lobes are avoided. Moreover, we have demonstrated rapid switching among the generated orbital angular momentum modes at the speed of 10 kHz, which is much faster than that of the usual method realized by spatial light modulators (SLMs). The proposed method is very beneficial for the optical communication and trapping or manipulating the small particle based on orbital angular momentum modes.
Stochastic resonance of periodic volatility in financial markets with stock crashes
Authors: Zhou Ruo-Wei , Zhong Guang-Yan , Li Jiang-Cheng , Li Yun-Xian , He Feng
Published: August 2018

We investigate the stochastic resonance of periodic volatility in two financial markets with stock crashes for Dow Jones component stocks and Hang Seng index, based on the modified Heston model with an effective potential to describe the stock crashes. We introduce a cosine term to Heston model and develop a modified Heston model with periodic stochastic volatility for capturing the periodicity of the volatility process or volatility clustering which was observed in historical financial data sets. The proposed model was tested against Dow Jones industrial and Hang Seng index data. The experimental results demonstrate that the proposed model fits the historical data well when compared with the original Heston model. The signal power amplification (SPA) is calculated and studied to investigate the stochastic resonance of the proposed dynamic system. Experimental results suggest that: (i) optimal values of volatility parameters can be identified which maximize the effects of systematic and non-systematic randomness to the market periodicity; (ii) different values of correlation strength between noise sources will cause critical phenomenon and induce single or multiple resonances.
Modification of polypropylene with nanosized α-Al2O3 powders prepared by the mechanochemical method
Authors: Gao Huiying , Li Zhiyong , Zhao Peng , Li Yankun , Zhang Zhenru , Zhang Mengyao
Published: August 2018

Nanosized [Formula: see text]-Al2O3 powders were prepared by the mechanochemical method, with AlCl[Formula: see text]H2O and NH4HCO3 as raw materials, the environmentally friendly starch as an effective dispersant. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were employed to characterize the ammonium aluminum carbonate hydroxide (AACH) precursor and products. The results show that nanosized spherical [Formula: see text]-Al2O3 powders without hard agglomeration and with particle size in the range of 20–40 nm can be obtained by this novel and green method. Then, polypropylene (PP)/nano [Formula: see text]-Al2O3 nanocomposites were prepared by melt blending in a mixer apparatus. The crystallization behavior and mechanical properties of PP/[Formula: see text]-Al2O3 nanocomposites were further investigated in this study. Wide-angle X-ray diffraction (WAXD) results show that a small amount of [Formula: see text]-crystal of PP forms after adding [Formula: see text]-Al2O3 nanoparticles. According to differential scanning calorimetric (DSC) measurement, the [Formula: see text]-Al2O3 nanoparticles make crystallization temperature of PP enhanced by acting as effective nucleating agents. The tensile strength and impact strength were both improved significantly with the addition of [Formula: see text]-Al2O3 nanoparticles through tensile and impact tests. Scanning electron microscopy (SEM) observation showed that the fracture surface became rougher and further confirmed the above result.
Modeling and simulation of traffic flow under different combination setting of taxi stop and bus stop
Authors: Zeng Jun-Wei , Qian Yong-Sheng , Wang Hui , Wei Xu-Ting
Published: August 2018

Taxis and buses have significant influence on traffic flow due to their special moving and stopping behavior. Based on the analysis of their operation and stopping characteristics, a two-lane cellular automaton model for urban roads considering the influence of stopping behavior is established, the vehicle type, cell length and moving speed are re-described. Considering the linear taxi stop and the linear bus stop, the characteristics of traffic flow under two different combination settings are studied. The numerical simulation results show that the combined bottleneck effect has little impact on flow rate and average speed when the bus stop is set on the upstream of the taxi stop, and the distance between stops should be 50 m. These findings lay a solid foundation for better description of urban traffic flow and enable better scientific planning and control of urban traffic.
Quantum error-correcting output codes
Authors: Windridge David , Mengoni Riccardo , Nagarajan Rajagopal
Published: August 2018

Quantum machine learning is the aspect of quantum computing concerned with the design of algorithms capable of generalized learning from labeled training data by effectively exploiting quantum effects. Error-correcting output codes (ECOC) are a standard setting in machine learning for efficiently rendering the collective outputs of a binary classifier, such as the support vector machine, as a multi-class decision procedure. Appropriate choice of error-correcting codes further enables incorrect individual classification decisions to be effectively corrected in the composite output. In this paper, we propose an appropriate quantization of the ECOC process, based on the quantum support vector machine. We will show that, in addition to the usual benefits of quantizing machine learning, this technique leads to an exponential reduction in the number of logic gates required for effective correction of classification error.
Electrochemical Determination of Paracetamol at Poly(3-Methylthiophene)/Reduced Graphene Oxide Modified Glassy Carbon Electrode
Authors: Li Caiwei , Si Weimeng , Wu Yuting , Zhang Cheng , Lei Wu , Hao Qingli
Published: August 2018

Poly(3-methylthiophene)/reduced graphene oxide (P3MT/RGO) modified glassy carbon electrode (GCE) was fabricated via a facile procedure. P3MT was directly electrodeposited on the RGO coated electrode and employed for the electrochemical detection of paracetamol (PCT). The morphology of composite was characterized by scanning electron microscopy (SEM). Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to investigate the electrochemical behaviors of PCT on P3MT/RGO/GCE. Experimental parameters, such as the scan rates, polymerization laps and the pH of buffer solution were optimized. Under the optimal conditions, the anodic peak current in DPVs varies linearly with the concentration of PCT, and the limit of detection was 0.025[Formula: see text][Formula: see text]M. Moreover, the proposed P3MT/RGO/GCE also exhibited superior stability and reproducibility.
Structure and Microwave Absorption Properties of Polyaniline/Zn Ferrite Composites
Authors: Xing Honglong , Liu Ye , Liu Zhenfeng , Wang Huan , Jia Hanxiao
Published: August 2018

Polyaniline (PANI)/Zn ferrite composites were fabricated by simple two-step method. The crystal phase, particle size, morphology, thermal stability and conductivity were characterized. Electromagnetic parameters of PANI/Zn ferrite composites were measured at room temperature in the frequency of 2–18[Formula: see text]GHz. The prepared composite had an amorphous fluffy structure, Zn ferrite nanoparticles with diameters ranging from 20[Formula: see text]nm to 30[Formula: see text]nm are encapsulated in PANI or on PANI surface, and the thermal stability of the composite is poor. But Zn ferrite content plays a key role in influencing this structure and regulating microwave attenuation capability. The PANI/Zn ferrite composites showed an enhanced microwave absorption performance in Ku band at thin coating thickness which corresponds to RL value below [Formula: see text][Formula: see text]dB and the minimum reflection loss (RL) is [Formula: see text][Formula: see text]dB at 17.6[Formula: see text]GHz with the coating thickness of 1.4[Formula: see text]mm.
Most Speculative Attacks Do Not Succeed: Currency Crises and Currency Crashes
Authors: Almahmood Hassan , Munyif Munif Al , Willett Thomas D.
Published: August 2018

While there has been considerable research on currency crises, relatively little attention has been given to whether they are successful or not. We investigate this question for a set of 32 emerging market economies for the period 1980–2014. In the literature, many different measures of currency crises have been used, but almost all use some variants of exchange market pressure indices that look at changes in exchange rates, international reserves, and often also interest rates. These vary mainly in their specific specifications such as how to weigh the different variables. Therefore, to check the robustness of our results we use six different specifications. A second type of measure is also sometimes used. These focus only on large depreciations of exchange rates. While often called measures of currency crises they are really only measures of currency crashes. We thus take this approach as a measure of successful attacks. Using a wider range of thresholds than studies such as Lavean and Valencia’s, a well-known dataset of different types of financial crises, we still find that the vast majority of speculative attacks are not successful.
Donors’ Trade and Their Supply of Development Aid Related to the Trade Sector: Does Donors’ Output Gap Matter?
Authors: Gnangnon Sèna Kimm
Published: August 2018

This paper complements the literature on the impact of donor-countries’ trade on their supply of Official Development Aid relating to the trade sector (ODATRADE). It investigates whether the impact of donor-countries’ trade balance (including overall trade balance in goods and services, trade balance in goods vis-à-vis developing and developed countries, and trade balance in services) on ODATRADE depends on the level of donor-countries’ output gap. Relying on a sample of 22 donor-countries over the period 1967–2015, the empirical analysis shows that donors’ output gap does matter for the impact of trade balance variables on ODATRADE.
The Impact of Foreign Direct Investment on Home Country Exports
Authors: Silva Vera , Forte Rosa
Published: August 2018

Exports and foreign direct investment (FDI) are two alternative foreign markets entry modes. From a theoretical point of view, there are arguments which support two different relationships between FDI and exports: complementary and substitution. Most empirical studies, however, have concluded with a complementary relationship. Since existing studies at more disaggregated levels have focused solely on the manufacturing industry, this paper aims at studying the relationship between FDI and home country exports based on a large sample of Portuguese firms, belonging to manufacturing and services, for the period 2006–2012. Using a fixed-effects model, results obtained suggest that the control of heterogeneity between firms is essential to clarify the relationship between FDI and exports and this has been a factor often overlooked.
THIS TIME IT IS DIFFERENT! OR NOT? DISCOUNTING PAST DATA WHEN PREDICTING THE FUTURE
Authors: FRANSES PHILIP HANS , JANSSENS EVA
Published: August 2018

We employ a simple method based on logistic weighted least squares to diagnose which past data are less or more useful for predicting the future course of a variable. A simulation experiment shows its merits. An illustration for monthly industrial production series for 17 countries suggests that earlier data are useful for the prediction in a crisis period (2006–2011) and for the period after the crisis (2011–2016). Hence, this time, apparently it was not that different after all.
HERDING IN CRYPTO-CURRENCY MARKETS
Authors: AJAZ TAUFEEQ , KUMAR ANOOP S.
Published: August 2018

We test for herding in crypto-currency markets using the CSAD method of Chang et al. (2000). Daily returns of 6 major crypto-currencies and market index CCI30 for the period 07-08-2015 t0 18-01-2018 is used. Possibility of herding under up and down market and high and low volatility is tested. Herding is found under up and down market activity, indicating over-enthusiasm and over-reaction. Market volatility is found not to have any significant impact on herding behavior. Herding is found to be dependent upon the market activity rather than market volatility.
Sediment Resuspension and Transport by Internal Solitary Waves
Authors: Boegman Leon , Stastna Marek
Published: August 2018

Large-amplitude internal waves induce currents and turbulence in the bottom boundary layer (BBL) and are thus a key driver of sediment movement on the continental margins. Observations of internal wave–induced sediment resuspension and transport cover significant portions of the world's oceans. Research on BBL instabilities, induced by internal waves, has identified several mechanisms by which the BBL is energized and sediment may be resuspended. Due to the complexity of the induced currents, process-oriented research using theory, direct numerical simulations, and laboratory experiments has played a vital role. However, experiments and simulations have inherent limitations as analogs for oceanic conditions due to disparities in Reynolds number and grid resolution, respectively. Parameterizations are needed for modeling resuspension from observed data and in larger-scale models, with the efficacy of parameterizations based on the quadratic stress largely determining the accuracy of present field-scale efforts.
Expansion capacity of human muscle progenitor cells differs by age, sex, and metabolic fuel preference
Authors: Riddle Emily S. , Bender Erica L. , Thalacker-Mercer Anna E.
Published: August 2018

Activation of satellite cells and expansion of the muscle progenitor cell (MPC) population are essential to generate a sufficient number of cells to repair damaged skeletal muscle. Proliferating MPCs have high energetic and biosynthetic material requirements, and the ability to utilize oxidative phosphorylation (OXPHOS) and/or glycolysis may affect expansion capacity of MPCs. In the present study, we investigated the effect of donor age and sex on human (h)MPC expansion capacity and metabolic fuel preference. hMPCs from young and old male and female donors were grown for 408 h (17 days). Percent confluence, live nuclei count, and dead cell count were measured every 24 h. Metabolic phenotype was assessed by glucose uptake, expression of genes related to glycolysis and OXPHOS, and the Seahorse XF24 Phenotype Test Kit during the exponential phase of growth. hMPCs from old male donors had impaired expansion capacity secondary to heightened cell death early in expansion compared with hMPCs from young male donors, an effect not observed in female hMPCs. Age-related differences in metabolism were also sex dependent; markers of OXPHOS were altered in old (vs. young) male hMPCs, whereas markers of metabolism were largely unaffected by age in female hMPCs. For the first time, we identify sex-specific differences in cell death and OXPHOS that contribute to impaired expansion capacity of hMPC cell populations with age.
Fetal undernutrition, placental insufficiency, and pancreatic β-cell development programming in utero
Authors: Mohan Ramkumar , Baumann Daniel , Alejandro Emilyn Uy
Published: August 2018

The prevalence of obesity and type 2 (T2D) diabetes is a major health concern in the United States and around the world. T2D is a complex disease characterized by pancreatic β-cell failure in association with obesity and insulin resistance in peripheral tissues. Although several genes associated with T2D have been identified, it is speculated that genetic variants account for only <10% of the risk for this disease. A strong body of data from both human epidemiological and animal studies shows that fetal nutrient factors in utero confer significant susceptibility to T2D. Numerous studies done in animals have shown that suboptimal maternal environment or placental insufficiency causes intrauterine growth restriction (IUGR) in the fetus, a critical factor known to predispose offspring to obesity and T2D, in part by causing permanent consequences in total functional β-cell mass. This review will focus on the potential contribution of the placenta in fetal programming of obesity and TD and its likely impact on pancreatic β-cell development and growth.
Potassium conservation is impaired in mice with reduced renal expression of Kir4.1
Authors: Malik Sundeep , Lambert Emily , Zhang Junhui , Wang Tong , Clark Heather L. , Cypress Michael , Goldman Bruce I. , Porter George A. , Pena Salvador , Nino Wilson , Gray Daniel A.
Published: August 2018

To better understand the role of the inward-rectifying K channel Kir4.1 (KCNJ10) in the distal nephron, we initially studied a global Kir4.1 knockout mouse (gKO), which demonstrated the hypokalemia and hypomagnesemia seen in SeSAME/EAST syndrome and was associated with reduced Na/Cl cotransporter (NCC) expression. Lethality by ~3 wk, however, limits the usefulness of this model, so we developed a kidney-specific Kir4.1 “knockdown” mouse (ksKD) using a cadherin 16 promoter and Cre-loxP methodology. These mice appeared normal and survived to adulthood. Kir4.1 protein expression was decreased ~50% vs. wild-type (WT) mice by immunoblotting, and immunofluorescence showed moderately reduced Kir4.1 staining in distal convoluted tubule that was minimal or absent in connecting tubule and cortical collecting duct. Under control conditions, the ksKD mice showed metabolic alkalosis and relative hypercalcemia but were normokalemic and mildly hypermagnesemic despite decreased NCC expression. In addition, the mice had a severe urinary concentrating defect associated with hypernatremia, enlarged kidneys with tubulocystic dilations, and reduced aquaporin-3 expression. On a K/Mg-free diet for 1 wk, however, ksKD mice showed marked hypokalemia (serum K: 1.5 ± 0.1 vs. 3.0 ± 0.1 mEq/l for WT), which was associated with renal K wasting (transtubular K gradient: 11.4 ± 0.8 vs. 1.6 ± 0.4 in WT). Phosphorylated-NCC expression increased in WT but not ksKD mice on the K/Mg-free diet, suggesting that loss of NCC adaptation underlies the hypokalemia. In conclusion, even modest reduction in Kir4.1 expression results in impaired K conservation, which appears to be mediated by reduced expression of activated NCC.
Absence of renal hypoxia in the subacute phase of severe renal ischemia-reperfusion injury
Authors: Ow Connie P. C. , Ngo Jennifer P. , Ullah Md Mahbub , Barsha Giannie , Meex Ruth C. , Watt Matthew J. , Hilliard Lucinda M. , Koeners Maarten P. , Evans Roger G.
Published: August 2018

Tissue hypoxia has been proposed as an important event in renal ischemia-reperfusion injury (IRI), particularly during the period of ischemia and in the immediate hours following reperfusion. However, little is known about renal oxygenation during the subacute phase of IRI. We employed four different methods to assess the temporal and spatial changes in tissue oxygenation during the subacute phase (24 h and 5 days after reperfusion) of a severe form of renal IRI in rats. We hypothesized that the kidney is hypoxic 24 h and 5 days after an hour of bilateral renal ischemia, driven by a disturbed balance between renal oxygen delivery (Do2) and oxygen consumption (V̇o2). Renal Do2 was not significantly reduced in the subacute phase of IRI. In contrast, renal V̇o2 was 55% less 24 h after reperfusion and 49% less 5 days after reperfusion than after sham ischemia. Inner medullary tissue Po2, measured by radiotelemetry, was 25 ± 12% (mean ± SE) greater 24 h after ischemia than after sham ischemia. By 5 days after reperfusion, tissue Po2 was similar to that in rats subjected to sham ischemia. Tissue Po2 measured by Clark electrode was consistently greater 24 h, but not 5 days, after ischemia than after sham ischemia. Cellular hypoxia, assessed by pimonidazole adduct immunohistochemistry, was largely absent at both time points, and tissue levels of hypoxia-inducible factors were downregulated following renal ischemia. Thus, in this model of severe IRI, tissue hypoxia does not appear to be an obligatory event during the subacute phase, likely because of the markedly reduced oxygen consumption.
MAGI-2 and scaffold proteins in glomerulopathy
Authors: Empitu Maulana A. , Kadariswantiningsih Ika N. , Aizawa Masashi , Asanuma Katsuhiko
Published: August 2018

In many cells and tissues, including the glomerular filtration barrier, scaffold proteins are critical in optimizing signal transduction by enhancing structural stability and functionality of their ligands. Recently, mutations in scaffold protein membrane-associated guanylate kinase inverted 2 (MAGI-2) encoding gene were identified among the etiology of steroid-resistant nephrotic syndrome. MAGI-2 interacts with core proteins of multiple pathways, such as transforming growth factor-β signaling, planar cell polarity pathway, and Wnt/β-catenin signaling in podocyte and slit diaphragm. Through the interaction with its ligand, MAGI-2 modulates the regulation of apoptosis, cytoskeletal reorganization, and glomerular development. This review aims to summarize recent findings on the role of MAGI-2 and some other scaffold proteins, such as nephrin and synaptopodin, in the underlying mechanisms of glomerulopathy.
Activity of near-response cells during disconjugate saccades in strabismic monkeys
Authors: Pallus Adam , Walton Mark M. G. , Mustari Michael
Published: August 2018

Infantile strabismus is a common disorder characterized by a chronic misalignment of the eyes, impairment of binocular vision, and oculomotor abnormalities. Nonhuman primates with strabismus, induced in infancy, show a pattern of abnormalities similar to those of strabismic children. This allows strabismic nonhuman primates to serve as an ideal animal model to examine neural mechanisms associated with aberrant oculomotor behavior. Here, we test the hypothesis that impairment of disparity vergence and horizontal saccade disconjugacy in exotropia and esotropia are associated with disrupted tuning of near- and far-response neurons in the supraoculomotor area (SOA). In normal animals, these neurons carry signals related to vergence position and/or velocity. We hypothesized that, in strabismus, these neurons modulate inappropriately in association with saccades between equidistant targets. We recorded from 62 SOA neurons from 4 strabismic animals (2 esotropes and 2 exotropes) during visually guided saccades to a target that stepped to different locations on a tangent screen. Under these same conditions, SOA neurons in normal animals show no detectable modulation. In our strabismic subjects, we found that a subset of SOA neurons carry weak vergence velocity signals during saccades. In addition, a subset of SOA neurons showed clear modulation associated with slow fluctuations of horizontal strabismus angle in the absence of a saccade. We suggest that abnormal SOA activity contributes to fixation instability but plays only a minor role in the horizontal disconjugacy of saccades that do not switch fixation from one eye to the other.

NEW & NOTEWORTHY The present study is the first to investigate the activity of neurons in the supraoculomotor area (SOA) during horizontally disconjugate saccades in a nonhuman primate model of infantile strabismus. We report that fluctuations of horizontal strabismus angle, during fixation of static targets on a tangent screen, are associated with contextually inappropriate modulation of SOA activity. However, firing rate modulation during saccades is too weak to make a major contribution to horizontal disconjugacy.
Rapid homeostatic downregulation of LTP by extrasynaptic GluN2B receptors
Authors: Delgado Jary Y. , Fink Ann E. , Grant Seth G. N. , O'Dell Thomas J. , Opazo Patricio
Published: August 2018

Although the activation of extrasynaptic GluN2B-containing N-methyl-d-aspartate (NMDA) receptors has been implicated in neurodegenerative diseases, such as Alzheimer’s and Huntington’s disease, their physiological function remains unknown. In this study, we found that extrasynaptic GluN2B receptors play a homeostatic role by antagonizing long-term potentiation (LTP) induction under conditions of prolonged synaptic stimulation. In particular, we have previously found that brief theta-pulse stimulation (5 Hz for 30 s) triggers robust LTP, whereas longer stimulation times (5 Hz for 3 min) have no effect on basal synaptic transmission in the hippocampal CA1 region. Here, we show that prolonged stimulation blocked LTP by activating extrasynaptic GluN2B receptors via glutamate spillover. In addition, we found that this homeostatic mechanism was absent in slices from the SAP102 knockout, providing evidence for a functional coupling between extrasynaptic GluN2B and the SAP102 scaffold protein. In conclusion, we uncovered a rapid homeostatic mechanism that antagonizes LTP induction via the activation of extrasynaptic GluN2B-containing NMDA receptors.

NEW & NOTEWORTHY Although long-term potentiation (LTP) is an attractive model for memory storage, it tends to destabilize neuronal circuits because it drives synapses toward a maximum value. Unless opposed by homeostatic mechanisms operating through negative feedback rules, cumulative LTP could render synapses unable to encode additional information. In this study, we uncovered a rapid homeostatic mechanism that antagonizes LTP induction under conditions of prolonged synaptic stimulation via the activation of an extrasynaptic GluN2B-SAP102 complex.
Physiological Consequences of Coronary Arteriolar Dysfunction and Its Influence on Cardiovascular Disease
Authors: Allaqaband Hassan , Gutterman David D. , Kadlec Andrew O.
Published: August 2018

To date, the major focus of diagnostic modalities and interventions to treat coronary artery disease has been the large epicardial vessels. Despite substantial data showing that microcirculatory dysfunction is a strong predictor of future adverse cardiovascular events, very little research has gone into developing techniques for in vivo diagnosis and therapeutic interventions to improve microcirculatory function. In this review, we will discuss the pathophysiology of coronary arteriolar dysfunction, define its prognostic implications, evaluate the diagnostic modalities available, and provide speculation on current and potential therapeutic opportunities.