bluuebunny/crossref_metadata_2025 huggingface dataset:
American cutaneous leishmaniasis in French Guiana: an epidemiological update and study of environmental risk factors
Authors: Loiseau Rémi , Nabet Cecile , Simon Stephane , Ginouves Marine , Brousse Paul , Blanchet Denis , Demar Magalie , Couppie Pierre , Blaizot Romain
Published: September 2019

Background

American cutaneous leishmaniasis (ACL) is endemic in French Guiana. Its epidemiology is evolving, notably because of immigration, anthropization of natural areas, and new microbiological methods. Our first objective was to update epidemiological data. Our second objective was to look for risk factors of ACL.

Methods

This multicentric study was conducted from October 2017 to June 2018 in French Guiana. Patients with suspicion of mucocutaneous leishmaniasis were included in case of positive smear, culture, or PCR‐RFLP on skin biopsy.

Results

One hundred and twenty‐three patients met the inclusion criteria. Among those patients, 59.3% were Brazilian, mostly gold miners. Most of them (58%) were between 16 and 40 years old, and 69% were male. A large proportion of patients lived in traditional wooden houses (51%). Patients living in coastal towns were usually infected during trips to the primary forest (60%) and had a shorter time to diagnosis than workers of the hinterland. Among environmental risk factors, the presence of a water spring (40%) and dogs around houses (40%) were frequently reported. Leishmania guyanensis represented 80% of cases, followed by Leishmania braziliensis (6%), Leishmania naiffi (2%), and Leishmania amazonensis (1%).

Conclusions

Gold mining and trips to the primary forest represent high‐risk situations for ACL in French Guiana, where the population of infected patients is dominated by Brazilian immigrants. Possible environmental risk factors such as the presence of dogs, water sources, and traditional wooden houses require further investigation.
Mediating role of self‐efficacy in the relationship between family social support and hypertension self‐care behaviours: A cross‐sectional study of Saudi men with hypertension
Authors: Bahari Ghareeb , Scafide Katherine , Krall Jenna , Mallinson R. Kevin , Weinstein Ali A.
Published: September 2019

Background

Self‐efficacy and family social support are significantly associated with hypertension self‐care behaviours. However, little is known about their mechanism in Saudi Arabia. This cross‐sectional study aimed to examine the relationships among family social support, self‐efficacy, and self‐care behaviours among men with hypertension in Saudi Arabia.

Methods

Data were collected from May to August of 2018. The Hypertension Self‐Care Profile and the Perceived Social Support from Friends and Family scales were used to measure the study variables. Multiple linear regression was used to analyse the relationships between the variables, and the Baron and Kenny test was used to assess if self‐efficacy mediated the relationship between family social support and hypertension self‐care behaviours.

Results

Respondents (N = 158) from the Jizan and Al‐Sharqia regions of Saudi Arabia completed the survey. Family social support and self‐efficacy were significantly associated with hypertension self‐care behaviours. In regression, self‐efficacy was the only variable significantly associated with hypertension self‐care behaviours. Self‐efficacy fully mediated the relationship between family social support and hypertension self‐care behaviours.

Conclusions

Interventions to enhance hypertension self‐care behaviours among Saudi men could focus on increasing individual's self‐confidence to perform specific healthy behaviours. Family support can also contribute to the performance of hypertension self‐care behaviours.
Clinical significance of granulomas in Crohn's disease: A systematic review and meta‐analysis
Authors: Hong Seung Wook , Yoon Hyuk , Shin Cheol Min , Park Young Soo , Kim Nayoung , Lee Dong Ho , Kim Joo Sung
Published: September 2019

Background and Aim

Epithelioid granuloma is one hallmark used to histologically diagnose Crohn's disease (CD). However, the clinical significance of granulomas in CD is unclear. Therefore, we performed a meta‐analysis to compare the clinical features with CD according to the presence of granulomas.

Methods

A literature search in PubMed, EMBASE, and Cochrane databases was performed on manuscripts published until October 2018. We included studies that met the following inclusion criteria: (i) patient: patients with CD; (ii) exposure: granulomas on the pathology; (iii) comparator: no granulomas; and (iv) outcomes: disease location, disease behavior, perianal disease, disease activity, use of biologics, and CD‐associated hospitalization, surgery.

Results

Nineteen studies met our inclusion criteria. Granulomas in CD patients were associated with a higher proportion of ileocolonic disease (odds ratio [OR]: 1.49, 95% confidence interval [CI]: 1.21–1.83), a higher proportion of upper gastrointestinal disease (OR: 2.25, 95% CI: 1.28–3.95), a higher proportion of penetrating behavior (OR: 1.48, 95% CI: 1.09–2.01), a higher prevalence of perianal disease (OR: 2.15, 95% CI: 1.48–3.11), and a higher severity index at presentation (standardized mean difference: 0.20, 95% CI: 0.09–0.32). In addition, the use of biologics was significantly higher in CD patients with granulomas compared with without granulomas (OR: 1.66, 95% CI: 1.07–2.59). The presence of granulomas was significantly associated with CD‐associated hospitalization (OR: 3.88, 95% CI: 1.44–10.49), but not with CD‐associated surgery.

Conclusions

Clinical features in CD patients were significantly different according to the presence of granulomas. It may indicate a more aggressive phenotype of CD.
Comment on Physical Performance in Memory Clinic Patients: The Potential Role of the White Matter Network
Authors: Cooper Christine , Marebwa Barbara , Bonilha Leonardo
Published: September 2019

See the Reply by Verwer et al.
Clinical spectrum of AIFM1‐associated disease in an Irish family, from mild neuropathy to severe cerebellar ataxia with colour blindness
Authors: Bogdanova‐Mihaylova Petya , Alexander Michael D. , Murphy Raymond P. , Chen Hongying , Healy Daniel G. , Walsh Richard A. , Murphy Sinéad M.
Published: September 2019

Mutations in apoptosis‐inducing factor mitochondrion‐associated‐1 (AIFM1) cause X‐linked peripheral neuropathy (Cowchock syndrome, CMT4X); however, more recently a cerebellar presentation has been described. We describe a large Irish family with seven affected males. They presented with a variable age of onset, 18 months to 39 years of age. All developed variably present sensorineural deafness, peripheral neuropathy, cerebellar ataxia, and pyramidal involvement. In addition, three had colour vision deficiency. Scale for the assessment and rating of ataxia ranged 2 to 23/40, while Charcot‐Marie‐Tooth neuropathy score 2 varied between 7 and 13/36. All individuals had normal cognitive assessment. Neurophysiology demonstrated length‐dependent large‐fibre sensorimotor axonal neuropathy, with particular involvement of superficial radial sensory responses. Brain imaging, performed in four, revealed varying extent of cerebellar atrophy, and white matter changes in one. Optical coherence tomography was abnormal in one, who had unrelated eye pathology. Four obligate female carriers were assessed clinically, two of them neurophysiologically; all were unaffected. Whole genome sequencing demonstrated a previously reported hemizygous AIFM1 mutation. Analysis for mutations in other genes associated with colour deficiency was negative. AIFM1‐associated phenotype in this family demonstrated significant variability. To our knowledge, this is the first report of AIFM1‐associated colour blindness. Superficial radial nerve was particularly affected neurophysiologically, which could represent a phenotypic marker towards this specific genetic diagnosis.
Combination therapy with salicylic acid chemical peels, glycyrrhizin compound, and vitamin C for Riehl's melanosis
Authors: Wang Lian , Wen Xiang , Hao Dan , Li Yong , Du Dan , Jiang Xian
Published: September 2019

Background

Riehl's melanosis is a chronic, refractory disorder, which can adversely affect patient's quality of life. Intense pulse light, neodymium‐doped yttrium aluminum garnet laser, hydroquinone, tranexamic acid have been reported to treat this disease, but there have been few reports on the effectiveness of other treatments.

Aim

To assess the efficacy and safety of triple combination therapy with salicylic acid chemical peels, oral glycyrrhizin compound, and vitamin C for Riehl's melanosis.

Patients/Methods

Three patients diagnosed with Riehl's melanosis were enrolled. All patients were treated with glycyrrhizin compound (150 mg/d), vitamin C (100 mg/d), and salicylic acid 30% peels once every 2 weeks. Clinical photographs and VISIA were used to assess the efficacy.

Results

All patients received obvious improvement and reported no obvious side effects.

Conclusion

Triple combination therapy with salicylic acid peels, oral glycyrrhizin compound, and vitamin C is a safe and effective modality for Riehl's melanosis.
Erythematous nodules over the genitalia of a young boy
Authors: Ghosh Sudip Kumar , Panigrahi Avik
Published: September 2019

See Answer
THERMOGENIC PETROLEUM POTENTIAL OF THE NANKAI SUBDUCTION ZONE, OFFSHORE SW JAPAN
Authors: Shiraishi K. , Yamada Y. , Nibe T.
Published: September 2019

In the Kumano forearc basin, offshore SW Japan, the potential occurrence of hydrocarbons has been inferred from both geophysical surveys which point to the presence of natural gas hydrates, and geochemical analyses of gas samples recovered from boreholes and submarine mud volcanoes. The forearc basin is located in the inner part of the Nankai Trough where the Philippine Sea plate is subducting northwards beneath SW Japan. The basin succession unconformably overlies a deformed accretionary prism complex. Hydrocarbons with both microbial and thermogenic origins have been recorded in the Kumano Basin, but the thermogenic petroleum potential is poorly constrained because the regional‐scale geological architecture of the Nankai subduction zone is not well understood.

In this paper, the regional‐scale petroleum potential of the Nankai Trough is investigated based on the geological interpretation of new seismic reflection images. The images were derived from legacy seismic survey data using advanced processing techniques such as reverse time migration, which make use of both primary and multiple reflections in wide‐angle seismic data collected with ocean‐bottom seismographs. In the study area, a seaward‐dipping reflector was identified which terminates at the plate boundary décollement and which is interpreted as part of the boundary between previously‐identified older (>14 Ma) and younger (<6 Ma) accretionary prisms. A triangle body at the base of the younger accretionary prism is interpreted to consist of underthrusted sediments including thick hemipelagic mudstones with source rock potential which were scraped off the down‐going oceanic plate. These tentatively identified, deeply‐buried mudstones may have the potential to generate thermogenic hydrocarbons which may then migrate upwards along dipping carrier beds or faults and fractures to the unconformity at the base of the Kumano forearc basin succession. The presence of hydrocarbons in the accretionary prism may be inferred from positive amplitude anomalies which have been identified in the reprocessed multi‐channel seismic data.

The new reflection interpretations therefore allow the potential for thermogenic petroleum to be proposed in the study area. The hydrocarbon potential at this subduction margin may therefore rely not only on shallow microbial methane, but may also involve deeper, thermogenic petroleum generated within the underlying accretionary prism.
Effect of common and new gums on the quality, physical, and textural properties of bakery products: A review
Authors: Salehi Fakhreddin
Published: September 2019

Hydrocolloids (gums) have a good functional characteristic such as emulsifying, gelling, solubility, and textural improvement. In the bakery products, hydrocolloids were used to improving dough performance, bread and cake characteristics, sensorial quality, and extension the products shelf life. Several studies reported the potential use of hydrocolloids in breads, biscuits, cakes, and pasta formulation. The present review summarized the effect of the most common and new hydrocolloids (xanthan, guar, Arabic, carrageenan, karaya, alginate, acacia, methylcellulose, carboxy methyl cellulose, hydroxyl propyl methyl cellulose, locust bean, balangu seed, wild sage seed, basil seed, and cress seed gums) on the rheological, physicochemical, textural, and quality characteristics of bakery products. Gums addition improved volume and porosity of the breads and cakes. Gums influence on the gelatinization and retrogradation of starch and decreased the retrogradation of starch. In the bakery products, hydrocolloids were used to improving mixing and increasing the shelf life of the products through moisture preservation and avoidance of syneresis in some frozen foods. This study summarized the influence of the most common and new hydrocolloids on the rheological, physicochemical, textural, and quality characteristics of bakery products. Addition of seeds gum to the breads, biscuits, cakes, and pasta formula led to an increase in the viscosity of the batter. Also, the firmness of bakery products showed that they became softer with increasing gum levels.
Relationship between the frequency of nursing activities and adverse outcomes in patients with acute coronary syndrome: A retrospective cohort study
Authors: Yu Hye Yon , Ahn Eun Kyoung , Seo Eun Ji
Published: September 2019

The aim of this retrospective cohort study was to identify the relationship between the frequency of nursing activities during the first hospitalization and adverse outcomes in patients with acute coronary syndrome by using electronic health records. Patients diagnosed with acute coronary syndrome from April 2010 to April 2015 were examined for eligibility based on 36 months of major adverse cardiac events as the main outcome. Among the 652 patients who were enrolled, 66 patients experienced major adverse cardiac events. The average frequency of nursing activities was 1098.7 (±2703.8), and four variables (length of hospital stay, albumin level, hemoglobin level, and frequency of nursing activities) were significantly associated with 36 months of major adverse cardiac events. After adjusting for these variables, the frequency of nursing activities was found to be the only significant factor associated with the incidence of 36 months of major adverse cardiac events. This finding suggests that patients with acute coronary syndrome who require more frequent nursing activities during the first hospitalization could be vulnerable to adverse outcomes and should be closely monitored.
Unintentional non‐fatal hospitalised falls and motor vehicle injuries in the Auckland and Northland regions: Geographical patterns and associations with rurality
Authors: Zhao Jinfeng , Gulliver Pauline , Exeter Daniel J. , Lee Arier , Browne Michael , Ameratunga Shanthi
Published: September 2019

This paper examined the relationship between rurality and unintentional non‐fatal hospitalisations for falls and motorised vehicle transport injuries and their geographic patterns in New Zealand. Data were constructed from Statistics New Zealand's Integrated Data Infrastructure. Logistic regression revealed that the odds of hospitalisations from falls were lower in more rural areas, but motor vehicle injuries were higher. The odds of injured people being discharged from a ward increased with rurality for both injury types. This study discovered geographical disparities in the two injury types. The findings of this study direct attention to underlying contextual factors that require targeted prevention strategies.
Effects of antidepressant and antipsychotic use on weight gain: A systematic review
Authors: Alonso‐Pedrero Lucia , Bes‐Rastrollo Maira , Marti Amelia
Published: September 2019

Weight gain is an adverse effect of antidepressants and antipsychotics. This side effect can lead to numerous comorbidities and reduces life expectancy. The use of these drugs is increasing worldwide, and the weight gain produced by them represents a common clinical challenge. The goal of this systematic review was to evaluate the potential association of antidepressant and antipsychotic therapy with body weight gain in cohort studies. A search of cohort studies investigating the association between weight gain and the use of antidepressants and antipsychotics in individuals was conducted through the PubMed database from 1 January 2008 to 31 January 2019 following the PRISMA statement. We found 27 independent eligible cohort studies that included children (2‐18 years old) and adult (18‐103 years old) subjects. Most of the included studies showed a 5% weight gain in individuals using antidepressant therapy. However, Quetiapine, Haloperidol, Trifluoperazine, Risperidone, Aripiprazole, Olanzapine, and Clozapine increased body weight ≥7% from baseline, which is considered a clinically significant result. Weight loss was found in individuals treated with Bupropion. Further cohort studies with higher sample sizes and longer durations of treatment are needed to confirm our observations.
On the origin of schizophrenia: Testing evolutionary theories in the post‐genomic era
Authors: Nesic Milica J. , Stojkovic Biljana , Maric Nadja P.
Published: September 2019

Considering the relatively high heritability of schizophrenia and the fact that it significantly reduces the reproductive fitness of affected individuals, it is not clear how the disorder is still maintained in human populations at a disproportionally high prevalence. Many theories propose that the disorder is a result of a trade‐off between costs and benefits of the evolution of exclusively human adaptations. There have also been suggestions that schizophrenia risk alleles are accompanied with increase in fitness of affected persons or their relatives in both past and current social contexts. The discoveries of novel schizophrenia‐related genes and the advancements in comparative genomics (especially comparisons of the human genome and the genomes of related species, such as chimpanzees and extinct hominids) have finally made certain evolutionary theories testable. In this paper, we review the current understanding of the genetics of schizophrenia, the basic principles of evolution that complement our understanding of the subject, and the latest genetic studies that examine long‐standing evolutionary theories of schizophrenia using novel methodologies and data. We find that the origin of schizophrenia is complex and likely governed by different evolutionary mechanisms that are not mutually exclusive. Furthermore, the most recent evidence implies that schizophrenia cannot be comprehended as a trait that has elevated fitness in human evolutionary lineage, but has been a mildly deleterious by‐product of specific patterns of the evolution of the human brain. In other words, novel findings do not support previous hypotheses stating that schizophrenia risk genes have an evolutionary advantage.
Associations between paracetamol (acetaminophen) intake between 18 and 32 weeks gestation and neurocognitive outcomes in the child: A longitudinal cohort study
Authors: Golding Jean , Gregory Steven , Clark Rosie , Ellis Genette , Iles‐Caven Yasmin , Northstone Kate
Published: September 2019

Background

The majority of epidemiological studies concerning possible adverse effects of paracetamol (acetaminophen) in pregnancy have been focussed on childhood asthma. Initial results of a robust association have been confirmed in several studies. Recently, a few cohort studies have looked at particular neurocognitive outcomes, and several have implicated hyperactivity.

Objectives

In order to confirm these findings, further information and results are required. Here, we assess whether paracetamol intake between 18 and 32 weeks gestation is associated with childhood behavioural and cognitive outcomes using a large population.

Methods

Data collected by the Avon Longitudinal Study of Parents and Children (ALSPAC) at 32 weeks gestation and referring to the period from 18 to 32 weeks, identified 43.9% of women having taken paracetamol. We used an exposome analysis first to determine the background factors associated with pregnant women taking the drug, and then allowed for those factors to assess associations with child outcomes (measured using regression analyses).

Results

We identified 15 variables independently associated with taking paracetamol in this time period, which were used as potential confounders. Of the 135 neurocognitive variables considered, adjusting for the likelihood of false discovery, we identified 56 outcomes for adjusted analyses. Adjustment identified 12 showing independent associations with paracetamol use at P < .05, four of which were at P < .0001 (all related to child behaviours reported by the mother at 42 and 47 months; eg conduct problems: adjusted mean score + 0.22 (95% confidence interval 0.10, 0.33)). There were few associations with behavioural or neurocognitive outcomes after age 7‐8 years, whether reported by the mother or the teacher.

Conclusions

If paracetamol use in mid‐to‐late pregnancy has an adverse effect on child neurocognitive outcome, it appears to mainly relate to the pre‐school period. It is important that these results be tested using other datasets or methodologies before assuming that they are causal.
Kulikovskiyia gen. nov. (Bacillariophyceae) from the lateritic rock pools of the Western Ghats, India and from Hainan Province, China
Authors: Roy Surajit , Liu Yan , Kociolek John Patrick , Lowe Rex L. , Karthick Balasubramanian
Published: September 2019

A new triundulate naviculoid diatom genus is described from the Western Ghats of Peninsular India and Hainan Province, China. The new taxon, Kulikovskiyia gen. nov. has robust conical spines along its margin and at the apices and the external valve face has longitudinally‐oriented siliceous slat system extending the length of the valve. The external distal raphe ends bifurcate and terminates on the valve face. There appear to be superficial similarities between this Asian genus and species and Playaensis, a genus comprised of two species found only in the western USA. The systematic position of Kulikovskiyia is discussed, and other than noting its similarities to other biraphid naviculoid diatoms due to symmetry features and the position of the raphe, we are uncertain about its systematic placement at finer levels of classification.
Plant community development following reclamation of oil sands mines using four cover soil types in northern Alberta
Authors: Dhar Amalesh , Comeau Philip G. , Naeth M. Anne , Pinno Bradley D. , Vassov Robert
Published: September 2019

Understanding the effects of reclamation treatments on plant community development is an important step in setting realistic indicators and targets for reclamation of upland oil sands sites to forest ecosystems. We examine trends in cover, richness, evenness, and community composition for four cover soil types (clay over overburden, clay over tailings sand, peat‐mineral mix over overburden, and peat‐mineral mix over tailings sand) and natural boreal forests over a 20 year period in the mineable oil sands region of northern Alberta, Canada. Tree, shrub, and nonvascular plant species cover showed similar increases over time for all reclamation treatments, with corresponding declines in forb and graminoid cover with time. These trends resemble those in the natural boreal forests of the region and the trajectory of community development for the reclamation treatments appears to follow typical early successional trends for boreal forests. Species richness and diversity of natural forest differed significantly from reclamation treatments. Nonmetric multidimensional scaling ordination and multi‐response permutation procedure revealed that species composition was not affected by reclamation treatment but clearly differed from natural forest. Analysis of species co‐occurrence indicated random plant community assembly following reclamation, in contrast to a higher proportion of nonrandom plant community assembly in natural forests. Thus, reclaimed plant communities appear to be unstructured through year 20 and assembly is still in progress on these reclaimed sites.
A Case Study Evaluating the Risk of Infection from Middle Eastern Respiratory Syndrome Coronavirus (MERS‐CoV) in a Hospital Setting Through Bioaerosols
Authors: Adhikari Umesh , Chabrelie Alexandre , Weir Mark , Boehnke Kevin , McKenzie Erica , Ikner Luisa , Wang Meng , Wang Qing , Young Kyana , Haas Charles N. , Rose Joan , Mitchell Jade
Published: September 2019

Middle Eastern respiratory syndrome, an emerging viral infection with a global case fatality rate of 35.5%, caused major outbreaks first in 2012 and 2015, though new cases are continuously reported around the world. Transmission is believed to mainly occur in healthcare settings through aerosolized particles. This study uses Quantitative Microbial Risk Assessment to develop a generalizable model that can assist with interpreting reported outbreak data or predict risk of infection with or without the recommended strategies. The exposure scenario includes a single index patient emitting virus‐containing aerosols into the air by coughing, leading to short‐ and long‐range airborne exposures for other patients in the same room, nurses, healthcare workers, and family visitors. Aerosol transport modeling was coupled with Monte Carlo simulation to evaluate the risk of MERS illness for the exposed population. Results from a typical scenario show the daily mean risk of infection to be the highest for the nurses and healthcare workers (8.49 × 10−4 and 7.91 × 10−4, respectively), and the lowest for family visitors and patients staying in the same room (3.12 × 10−4 and 1.29 × 10−4, respectively). Sensitivity analysis indicates that more than 90% of the uncertainty in the risk characterization is due to the viral concentration in saliva. Assessment of risk interventions showed that respiratory masks were found to have a greater effect in reducing the risks for all the groups evaluated (>90% risk reduction), while increasing the air exchange was effective for the other patients in the same room only (up to 58% risk reduction).
Acute Shame Predicts Urges for Suicide but not for Substance Use in a Veteran Population
Authors: Cameron Amy Y. , Shea M. Tracie , Randall Alyson B.
Published: September 2019

Objective

There is an urgent need to identify ways to reduce rates of suicide among Veterans with a substance use disorder. Since co‐occurring disorders can make diagnosis and treatment complex, it is useful for the mental health field to examine common factors that may underlie both problems. One common factor that underlies both substance use and suicidal behavior is shame. This brief report presents data collected in an experimental study examining shame as an acute risk factor for suicide and substance use in Veterans.

Method

Thirty‐eight Veterans admitted to an inpatient Veterans Affairs Medical Center unit with suicidal ideation completed measures on depression, hopelessness, addiction, and suicidality. Participants were randomized to either a shame mood induction group or a control group, and completed pre‐ and postexperiment measures on urges for suicide, urges for substance use, and level of shame.

Results

Results indicate that an acute increase in shame resulted in an increase in an urge for suicide, but was not associated with changes in urges for substance use.

Conclusions

Acute feelings of shame may be a risk factor for increases in suicidal ideation. Limitations and suggestions for future directions are discussed.
In-Service Reading Teacher Efficacy
Authors: Wissink Barbara
Published: September 2019

The complex task of teaching students to read well is one that in-service elementary teachers may not feel fully prepared for, as the methods for teaching reading have changed significantly in the last decade. As the research on explicit literacy instruction continues to expand, today’s teachers require specific training on how to effectively teach reading and move beyond the traditional basal reading curriculum. Additionally, the research showed that a teacher’s self-efficacy was a contributing factor in the actual implementation of new literacy instruction knowledge. This mixed method study examined the varying levels of self-efficacy from 36 in-service elementary reading teachers who were enrolled in a literacy education graduate program. The data suggested that in-service elementary reading teachers’ self-efficacy fluctuated greatly due to additional professional development, administration support, and their years of teaching experience. Understanding how these components impacted an in-service reading teacher’s self-efficacy was important, as previous research has shown that the level of teacher efficacy may have an impact on the effectiveness of their reading instruction and their students’ literacy achievement in the elementary classroom.
Absence of hyperexcitability of spinal motoneurons in patients with amyotrophic lateral sclerosis
Authors: Marchand‐Pauvert Véronique , Peyre Iseline , Lackmy‐Vallee Alexandra , Querin Giorgia , Bede Peter , Lacomblez Lucette , Debs Rabab , Pradat Pierre‐François
Published: September 2019

Key points

Amyotrophic lateral sclerosis (ALS) motoneurons become hypoexcitable with disease progression in experimental models, raising questions about the neural hyperexcitability supported by clinical observations.

A variant of the ∆F method, based on motor unit discharge frequency modulations during recruitment and derecruitment, has been developed to investigate the motoneuron capacity to self‐sustained discharge in patients.

The modulation of motor unit firing rate during ramp contraction and vibration‐induced recruitment are modified in ALS, suggesting lower motoneuron capacity to self‐sustained discharge, which is a sign of hypoexcitability.

∆F‐D decreases with functional impairment and its reduction is more pronounced in fast progressors.

In patients with ALS, motoneurons exhibit hypoexcitability, which increases with disease progression.

Experimental models have primarily revealed spinal motoneuron hypoexcitability in amyotrophic lateral sclerosis (ALS), which is contentious considering the role of glutamate‐induced excitotoxicity in neurodegeneration and clinical features rather supporting hyperexcitability. This phenomenon was evaluated in human patients by investigating changes in motor unit firing during contraction and relaxation. Twenty‐two ALS patients with subtle motor deficits and 28 controls performed tonic contractions of extensor carpi radialis, triceps brachialis, tibialis anterior and quadriceps, aiming to isolate a low‐threshold unit (U1) on the electromyogram (EMG). Subsequently, they performed a stronger contraction or tendon vibration was delivered, to recruit higher threshold unit (U2) for 10 s before they relaxed progressively. EMG and motor unit potential analyses suggest altered neuromuscular function in all muscles, including those with normal strength (Medical Research Council score at 5). During the preconditioning tonic phase, U1 discharge frequency did not differ significantly between groups. During recruitment, the increase in U1 frequency (∆F‐R) was comparable between groups both during contraction and tendon vibration. During derecruitment, the decrease in U1 frequency (∆F‐D) was reduced in ALS regardless of the recruitment mode, particularly for ∆F‐R <8 Hz in the upper limbs, consistent with the muscle weakness profile of the group. ∆F‐D was associated with functional disability and its reduction was more pronounced in patients with more rapid disease progression rate. This in vivo study has demonstrated reduced motoneuron capacity for self‐sustained discharge, and further supports that motoneurons are normo‐ to hypoexcitable in ALS patients, similar to observations in experimental models.
Phase-Opposition Control of the Precessing Vortex Core in Turbulent Swirl Flames for Investigation of Mixing and Flame Stability
Authors: Lückoff Finn , Sieber Moritz , Paschereit Christian Oliver , Oberleithner Kilian
Published: September 2019

The precessing vortex core (PVC) is a helically shaped coherent flow structure that occurs in reacting and nonreacting swirling flows undergoing vortex breakdown. In swirl-stabilized combustors, the PVC affects important phenomena, such as turbulent mixing and thermoacoustic oscillations. In this work, a closed-loop flow control system is developed, which allows for phase-opposition control of the PVC, to achieve appropriate conditions to systematically investigate the influence of the PVC on turbulent flames. The control consists of a zero-net-mass-flux actuator placed in the mixing section of the combustor, where the PVC is most receptive to periodic forcing. The flow control system is characterized from pressure measurements and particle image velocimetry (PIV) and the impact on flame dynamics is extracted from OH*-chemiluminescence measurements. The data reveal that the PVC amplitude is considerably suppressed by the phase-opposition control without changing the overall characteristics of flow and flame, which is crucial to study the exclusive effect of the PVC on combustion processes. Moreover, the control allows the PVC amplitude to be adjusted gradually to investigate the PVC impact on turbulent mixing and flame dynamics. It is revealed that the PVC-induced flow fluctuations mainly affect the large-scale mixing, while the small scale mixing remains unchanged. This is because the suppression of the PVC allows other modes to become more dominant and the overall turbulent kinetic energy (TKE) budget remains unchanged. The destabilization of other modes, such as the axisymmetric mode, may have some implications on thermoacoustic instability.
Modal Analysis of Flange-Mounted Thermowells
Authors: Bartran Dave
Published: September 2019

Avoidance of flow-induced resonance is crucial in managing the failure risk of industrial temperature measurements. To this end, we find that modal analysis of thermowell installations using traditional shell and beam theory, may offer a useful screening tool for at risk installations. This is demonstrated in part by a comparison of predicted resonances of flange-mounted thermowells with those described in reported flow tests.
TURBODYNA: Centrifugal/Centripetal Turbomachinery Dynamic Simulator and Its Application on a Mixed Flow Turbine
Authors: Yang Bijie , Martinez-Botas Ricardo
Published: September 2019

One-dimensional (1D) modeling is crucial for turbomachinery unsteady performance prediction and system response assessment. The purpose of the paper is to describe a newly developed 1D modeling (turbomachinery dynamic simulator (TURBODYNA)) for turbomachinery. Different from classic 1D modeling, in TURBODYNA, rotor has been meshed and its unsteadiness due to flow field timescale is considered. Instead of direct using of performances maps, source terms are added in Euler equation set to simulate the rotor. By comparing 1D modeling with three-dimensional (3D) computational fluid dynamics (CFD) results, it shows that rotor unsteadiness is indispensable for a better prediction. In addition, different variables response to pulse differently. In the rotor, mass flow is close to quasi-steady while entropy is significantly unsteady. TURBODYNA can capture these features correctly and provide an accurate prediction on pressure wave transportation.
Gradient-Augmented Level Set Two-Phase Flow Method With Pretreated Reinitialization for Three-Dimensional Violent Sloshing
Authors: Xin Jianjian , Shi Fulong , Jin Qiu , Ma Lin
Published: September 2019

A three-dimensional (3D) gradient-augmented level set (GALS) two-phase flow model with a pretreated reinitialization procedure is developed to simulate violent sloshing in a cuboid tank. Based on a two-dimensional (2D) GALS method, 3D Hermite, and 3D Lagrange polynomial schemes are derived to interpolate the level set function and the velocity field at arbitrary positions over a cell, respectively. A reinitialization procedure is performed on a 3D narrow band to treat the strongly distorted interface and improve computational efficiency. In addition, an identification-correction technique is proposed and incorporated into the reinitialization procedure to treat the tiny droplet which can distort the free surface shape, even lead to computation failure. To validate the accuracy of the present GALS method and the effectiveness of the proposed identification-correction technique, a 3D velocity advection case is first simulated. The present method is validated to have better mass conservation property than the classical level set and original GALS methods. Also, distorted and thin interfaces are well captured on all grid resolutions by the present GALS method. Then, sloshing under coupled surge and sway excitation, sloshing under rotational excitation are simulated. Good agreements are obtained when the present wave and pressure results are compared with the experimental and numerical results. In addition, the highly nonlinear free surface is observed, and the relationship between the excitation frequency and the impulsive pressure is investigated.
Heat Transfer and Flow Structure in a Latticework Duct With Different Sidewalls
Authors: Du Wei , Luo Lei , Wang Songtao , Liu Jian , Sunden Bengt
Published: September 2019

Heat transfer characteristics in a latticework duct with various sidewalls are numerically investigated. The crossing angle is 90 deg and the number of subchannels is eleven on both the pressure side and suction side for each latticework duct. The thickness of the ribs is 8 mm and the distance between adjacent ribs is 24 mm. The investigation is conducted for various Reynolds numbers (11,000 to 55,000) and six different sidewalls. Flow structure, pressure drop, and heat transfer characteristics are analyzed. Results revealed that the sidewall has significant effects on heat transfer and flow structure. The triangle-shaped sidewall provides the highest Nusselt number accompanied by the highest friction factor. The sidewall with a slot shows the lowest friction factor and Nusselt number. An increased slot width decreased the Nusselt number and friction factor simultaneously.
Simulation of the Performance of the Venturi Scrubber for an Advanced Reactor Containment Venting Conditions
Authors: Paridhi Goel , Nayak Arun K.
Published: September 2019

Post Fukushima, nuclear plants are being retrofitted with severe accident mitigation measures. For attaining depressurization of the containment and mitigate the consequences of the release of the radioactivity to the environment during a severe accident condition, filtered containment venting systems (FCVS) are proposed to be installed in existing reactors and being designed for advanced reactors. The design of FCVS is particular to the reactor type. The FVCS configuration considered in this paper comprises of a manifold of venturi scrubber enclosed in a scrubber tank along with metal fiber filter and demister for an advanced Indian reactor. This study focuses on the assessment of the design of the venturi scrubber for the reactor conditions at which venting is carried out through a numerical model. The numerical model is first validated with experiments performed for prototypic conditions. The predicted pressure drop and the iodine absorption efficiency were found to be in good match with the experimental measurements. Subsequently, the model is implemented for predicting the hydrodynamics, i.e., pressure drop, droplet sizes and distribution, and iodine absorption for prototypic conditions. The hydrodynamics, i.e., pressure profile in the venturi scrubber showed a decrease in the converging section and in the throat section. The diverging section showed decrease in recovery of pressure with the decrease in gas flow because of the increased liquid loading to the scrubber. The iodine absorption efficiency showed a value of 92% for high gas velocity which decreased to 68% for the lowest gas flow rate.
Effect of Viscoelasticity on Arterial-Like Pulsatile Flow Dynamics and Energy
Authors: Elliott Winston , Guo Dongjie , Veldtman Gruschen , Tan Wei
Published: September 2019

Time-dependent arterial wall property is an important but difficult topic in vascular mechanics. Hysteresis, which appears during the measurement of arterial pressure–diameter relationship through a cardiac cycle, has been used to indicate time-dependent mechanics of arteries. However, the cause–effect relationship between viscoelastic (VE) properties of the arterial wall and hemodynamics, particularly the viscous contribution to hemodynamics, remains challenging. Herein, we show direct comparisons between elastic (E) (loss/storage < 0.1) and highly viscoelastic (loss/storage > 0.45) conduit structures with arterial-like compliance, in terms of their capability of altering pulsatile flow, wall shear, and energy level. Conduits were made from varying ratio of vinyl- and methyl-terminated poly(dimethylsiloxane) and were fit in a mimetic circulatory system measuring volumetric flow, pressure, and strain. Results indicated that when compared to elastic conduits, viscoelastic conduits attenuated lumen distension waveforms, producing an average of 11% greater cross-sectional area throughout a mimetic cardiac cycle. In response to such changes in lumen diameter strain, pressure and volumetric flow waves in viscoelastic conduits decreased by 3.9% and 6%, respectively, in the peak-to-peak amplitude. Importantly, the pulsatile waveforms for both diameter strain and volumetric flow demonstrated greater temporal alignment in viscoelastic conduits due to pulsation attenuation, resulting in 25% decrease in the oscillation of wall shear stress (WSS). We hope these findings may be used to further examine time-dependent arterial properties in disease prognosis and progression, as well as their use in vascular graft design.
Optical angular scatterometry: In-line metrology approach for roll-to-roll and nanoimprint fabrication
Authors: Faria-Briceno Juan J. , Zhu Ruichao , Sasidharan Vineeth , Neumann Alexander , Singhal Shrawan , Sreenivasan S. V. , Brueck S. R. J.
Published: September 2019

Metrology is an essential aspect of nanomanufacturing. Increasingly, nanoscale three-dimensional features are demanded for advanced applications, increasing the demands on metrology. New fabrication techniques such as roll-to-roll (R2R) processes are being developed for manufacturing large-area nanotechnology products such as wire-grid polarizers (WGP), metal-mesh grids, and metamaterials. Angular scatterometry has demonstrated noncontact, optical capabilities for characterizing WGP and photoresist structures with sub-100 nm dimensions. However, existing implementations are not applicable to real-time R2R nanofabrication due to both a requirement of rotating a small sample over a range of angles and measurement times that are incompatible with a moving R2R web. This work demonstrates a high-speed approach (2.5 kHz scanning) to angular scatterometry where the optical beam is scanned rather than the sample mount. The design uses a scanning mirror and high numerical aperture (NA) optics to vary the incident angle over a range from ∼29° to ∼59°. Approaches to increase the angular range are discussed. The scatterometry results are in good agreement with off-line scatterometry results for plane surface, 1D, and 2D patterned samples.
Charge-induced pattern displacement in E-beam lithography
Authors: Arat Kerim T. , Klimpel Thomas , Zonnevylle Aernout C. , Ketelaars Wilhelmus S. M. M. , Heerkens, Carel Th. H. , Hagen Cornelis W.
Published: September 2019

Electron beam lithography (EBL) requires conducting substrates to ensure pattern fidelity. However, there is an increasing interest in performing EBL on less well-conducting surfaces or even insulators, usually resulting in seriously distorted pattern formation. To understand the underlying charging phenomena, the authors use Monte Carlo simulations that include models for substrate charging, electron beam-induced current, and electric breakdown. Simulations of electron beam exposure of glass wafers are presented, exposing regular patterns which become distorted due to charge-induced beam deflection. The resulting displacements within the patterns are mapped and compared to experimental displacement maps obtained from patterns in PMMA resist on glass substrates. Displacements up to several hundreds of nanometers were observed at a primary beam energy of 50 keV. Also, various scan strategies were used to write the patterns, in the simulations as well as the experiments, revealing their strong effect on pattern distortion, in shape and in magnitude. A qualitative, in some cases even quantitative, good agreement was found between the simulations and the experiments, providing enough confidence in Monte Carlo simulations to predict charge-induced pattern displacement and shape distortion and to find smart scan strategies to minimize the effects of charging.
A Case When You Can’t Fool Mother Nature: Understanding and Addressing Issues Linked to Organizational Decisions Stemming From a Natural Disaster
Authors: Zapalac Ryan K. , Miller John J. , Miller Kelsey C.
Published: September 2019

Julie Tyler was recently hired as President of the Sacramento River Cats, a Triple-A affiliate of the San Francisco Giants. With a little over one month on the job, Julie encounters a situation she has never had to deal with when an earthquake strikes her facility. The River Cats are not severely impacted by the earthquake, but a rival organization (the Fresno Grizzlies; Triple-A affiliate of the Houston Astros) experiences some fairly serious damage and injuries. Julie has to decide whether to modify the schedule to meet the needs of the Grizzlies, to appease some of her other stakeholders with varying interests, and/or pursue a competitive advantage for her organization. Julie makes the decision to review a similar situation for guidance on her decision. The situation she decides to employ is a series relocation that the Houston Astros had to make to Tampa, Florida following the devastation created by Hurricane Harvey in August 2017. Her decision has to be made expeditiously as their next series with the Grizzlies takes place in four days.
Antimicrobial Resistance in Methicillin-Resistant
Staphylococcus aureus
to Newer Antimicrobial Agents
Authors: Watkins Richard R. , Holubar Marisa , David Michael Z.
Published: September 2019

Infections caused by methicillin-resistant
Staphylococcus aureus
(MRSA) result in significant morbidity and mortality for patients in both community and health care settings. This is primarily due to the difficulty in treating MRSA, which is often resistant to multiple classes of antibiotics.
Methyl Selenol as a Precursor in Selenite Reduction to Se/S Species by Methane-Oxidizing Bacteria
Authors: Eswayah Abdurrahman S. , Hondow Nicole , Scheinost Andreas C. , Merroun Mohamed , Romero-González Maria , Smith Thomas J. , Gardiner Philip H. E.
Published: September 2019

Aerobic methane-oxidizing bacteria are ubiquitous in the environment. Two well-characterized strains,
Mc
. capsulatus
(Bath) and
Methylosinus trichosporium
OB3b, representing gamma- and alphaproteobacterial methanotrophs, respectively, can convert selenite, an environmental pollutant, to volatile selenium compounds and selenium-containing particulates. Both conversions can be harnessed for the bioremediation of selenium pollution using biological or fossil methane as the feedstock, and these organisms could be used to produce selenium-containing particles for food and biotechnological applications. Using an extensive suite of techniques, we identified precursors of selenium nanoparticle formation and also found that these nanoparticles are made up of eight-membered mixed selenium and sulfur rings.