bluuebunny/crossref_metadata_2025 huggingface dataset:
Beyond Cognitive Screening: Establishing an Interprofessional Perioperative Brain Health Initiative
Authors: Decker Justyne , Kaloostian Carolyn L. , Gurvich Tatyana , Nguyen Phuong , Widjaja William , Cardona Hugo , Pagan Veronica , Motamed Arash , Peden Carol J.
Published: August 2020

OBJECTIVE

Perioperative neurocognitive disorder (PND) is now recognized as the most common postoperative complication in older surgical patients. Current multidisciplinary guidelines recommend simple cognitive screening of older adults before surgery. Patients identified at risk should have input from an interprofessional team with expertise caring for older surgical patients. Data suggest these recommendations are infrequently met. We set out to test feasibility of routine cognitive screening in a busy preoperative assessment clinic and establish a perioperative pathway with multidisciplinary support for patients identified at risk.

METHODS

We undertook a prospective quality improvement study. A cohort of 1,803 older surgical patients scheduled for preoperative evaluation was screened with the Mini‐Cog© test. As the project developed, we began confirmatory neurocognitive testing by occupational therapists for those patients flagged at risk. Patients confirmed at risk were referred for further evaluation by a geriatrician and geriatric pharmacist. Alerts were developed to flag patients at risk through their in‐patient journey, and a multidisciplinary team developed a comprehensive care pathway.

RESULTS

We demonstrated that implementing routine cognitive screening can be done in a busy clinic, regardless of prior experience. The prevalence of preoperative cognitive impairment was 21% in our older patients undergoing inpatient surgery, rising to 36% in those older than 85 years. When the Mini‐Cog results were not known to providers, they were unable to identify cognitive impairment in half of the patients, supporting the use of a validated screening test. We established an interprofessional team and pooled relevant recommendations into an age‐friendly perioperative care pathway for patients at increased cognitive risk.

CONCLUSION

Cognitive screening must be done to reliably identify older surgical patients at risk of PND. Demonstrating the prevalence of cognitive impairment in older surgical patients can provide impetus to develop a multidisciplinary team and care pathway with the aim of reducing the incidence of PNDs. J Am Geriatr Soc 68:2359–2364, 2020.
Early Carboniferous HP metamorphism in the Hida Gaien Belt, Japan: Implications for the Palaeozoic tectonic history of proto‐Japan
Authors: Yoshida Takumi , Taguchi Tomoki , Ueda Hayato , Horie Kenji , Satish‐Kumar M.
Published: August 2020

We report two new eclogite localities (at Kanayamadani and Shinadani) in the high‐P(HP) metamorphic rocks of the Omi area in the western most region of Niigata Prefecture, Japan, which form part of the Hida Gaien Belt, and determine metamorphic conditions and pressure–temperature (P–T) paths. The metamorphic evolution of the eclogites is characterized by a tight hairpin‐shapedP–Tpath from prograde epidote–blueschist facies to peak eclogite facies and then retrograde blueschist facies. The prograde metamorphic stage is characterized by various amphibole (winchite, barroisite, glaucophane) inclusions in garnet, whereas the peak eclogite facies assemblage is characterized by omphacite, garnet, phengite and rutile. PeakP–Tconditions of the eclogites were estimated to be ~600°C and up to 2.0 GPa by conventional cation‐exchange thermobarometry, Ti‐in‐zircon thermometry and quartz inclusion Raman barometry respectively. However, the Raman spectra of carbonaceous material thermometry of metapelites associated with the eclogites gave lower peak temperatures, possibly due to metamorphism at different conditions before being brought together during exhumation. The blueschist facies overprint following the peak of metamorphism is recognized by the abundance of glaucophane in the matrix. Zircon grains in blueschist facies metasedimentary samples from two localities adjacent to the eclogites have distinct oscillatory‐zoned cores and overgrowth rims. Laser ablation inductively coupled plasma mass spectrometry U–Pb ages of the detrital cores yield a wide range between 3,200 and 400 Ma, with a peak at 600–400 Ma. In the early Palaeozoic, proto‐Japan was located along the continental margin of the South China craton, providing the source of the older population of detrital zircon grains (3,200–600 Ma) deposited in the trench‐fill sediments. In addition, subduction‐related magmatismc. 500–400 Ma is recorded in the crust below proto‐Japan, which might have been the source for the younger detrital zircon grains. The peak metamorphic age was constrained by SHRIMP dating of the overgrowth rims, yielding Tournaisian ages of 347 ± 4 Ma, suggesting subduction in the early Carboniferous. Our results provide clear constraints on the initiation of subduction, accretion and the development of an arc‐trench system along the active continental margin of the South China craton and help to unravel the Palaeozoic tectonic history of proto‐Japan.
Benzimidazole‐based fluorophores for the detection of amyloid fibrils with higher sensitivity than Thioflavin‐T
Authors: Pravin Narayanaperumal , Kumar Rakesh , Tripathi Shalini , Kumar Pardeep , Mohite Ganesh M , Navalkar Ambuja , Panigrahi Rajlaxmi , Singh Namrata , Gadhe Laxmikant G. , Manchanda Shaffi , Shimozawa Makoto , Nilsson Per , Johansson Jan , Kumar Ashutosh , Maji Samir K. , Shanmugam Maheswaran
Published: August 2020

Protein aggregation into amyloid fibrils is a key feature of a multitude of neurodegenerative diseases such as Alzheimer's, Parkinson's, and Prion disease. To detect amyloid fibrils, fluorophores with high sensitivity and better efficiency coupled with the low toxicity are in high demand even to date. In this pursuit, we have unveiled two benzimidazole‐based fluorescence sensors ([C15H15N3] (C1) and [C16H16N3O2] (C2), which possess exceptional affinity toward different amyloid fibrils in its submicromolar concentration (8 × 10–9 M), whereas under a similar concentration, the gold standard Thioflavin‐T (ThT) fails to bind with amyloid fibrils. These fluorescent markers bind to α‐Syn amyloid fibrils as well as amyloid fibrils forming other proteins/peptides including Aβ42 amyloid fibrils. The 1H‐15N heteronuclear quantum correlation spectroscopy nuclear magnetic resonance data collected on wild‐type α‐Syn monomer with and without the fluorophores (C1 and C2) reveal that there is weak or no interactions between C1 or C2 with residues in α‐Syn monomer, which indirectly reflects the specific binding ability of C1 and C2 to the α‐Syn amyloid fibrils. Detailed studies further suggest that C1 and C2 can detect/bind with the α‐Syn amyloid fibril as low as 100 × 10–9 M. Extremely low or no cytotoxicity is observed for C1 and C2 and they do not interfere with α‐Syn fibrillation kinetics, unlike ThT. Both C1/C2 not only shows selective binding with amyloid fibrils forming various proteins/peptides but also displays excellent affinity and selectivity toward α‐Syn amyloid aggregates in SH‐SY5Y cells and Aβ42 amyloid plaques in animal brain tissues. Overall, our data show that the developed dyes could be used for the detection of amyloid fibrils including α‐Syn and Aβ42 amyloids with higher sensitivity as compared to currently used ThT.

image
Suppression of ovarian hormones in adolescent rats has no effect on anxiety‐like behaviour or c‐fos activation in the amygdala
Authors: Hodgson Amy R. , Richmond Claire , Tello Javier , Brown Gillian R.
Published: August 2020

In humans, sex differences in mood disorders emerge during adolescence, with prevalence rates being consistently higher in females than males. It has been hypothesised that exposure to endogenous ovarian hormones during adolescence enhances the susceptibility of females to mood disorders from this stage of life onwards. However, experimental evidence in favour of this hypothesis is lacking. In the present study, we examined the long‐term effects of suppressing adolescent gonadal hormone levels in a group of female Lister‐hooded rats via administration of a gonadotrophin‐releasing hormone antagonist (Antide; administered on postnatal day [PND] 28 and 42) compared to control females and males (n = 14 per group). We predicted that, in adulthood, Antide‐treated female rats would exhibit more male‐like behaviour than control females in novel environments (elevated‐plus maze, open field and light‐dark box), in response to novel objects and novel social partners, and in an acoustic startle task. Progesterone and luteinising hormone assays (which were conducted on blood samples collected on PND 55/56 and 69/70) confirmed that the hypothalamic‐pituitary‐gonadal axis was temporarily suppressed by Antide treatment. In addition, Antide‐treated females were found to exhibit a modest pubertal delay, as measured by vaginal opening, which was comparable in length to the pubertal delay that has been induced by adolescent exposure to alcohol or stress in previous studies of female rats. However, Antide‐treated females did not substantially differ from control females on any of the behavioural tests, despite the evidence for predicted sex differences in some measures. Following the acoustic startle response task, all subjects were culled and perfused, and c‐Fos staining was conducted in the medial and basolateral amygdala, with the results showing no significant differences in cell counts between the groups. These findings suggest that ovarian hormone exposure during adolescence does not have long‐term effects on anxiety‐related responses in female rats.
Massive atonic bleeding during cesarean delivery in a patient with chronic idiopathic intestinal pseudo‐obstruction: A case report and literature review
Authors: Katayama Yoshihiro , Kido Saki , Kai Shotaro , Nakano Takahiro , Hidaka Nobuhiro , Kato Kiyoko
Published: August 2020

A 35‐year‐old primigravid woman with chronic idiopathic intestinal pseudo‐obstruction presented to our institution. Except for an enlarged fetal bladder, her pregnancy was almost uneventful until she developed pre‐eclampsia requiring emergent cesarean section at 34 weeks gestation. After delivery, intractable uterine atony developed with blood loss reaching 3500 mL within 15 min. Following a B‐Lynch suture, the bleeding attenuated but uterine atony persisted; lochia persisted for 3 months post‐partum. The infant was diagnosed with megacystis microcolon intestinal hypoperistalsis syndrome after birth. The mother's clinical course and previous reports suggested that atonic bleeding was associated with the pathology of chronic idiopathic intestinal pseudo‐obstruction; the infant's disease was considered to be maternal‐related disease. Clinicians should be vigilant in pregnant patients with chronic idiopathic intestinal pseudo‐obstruction especially with these complications.
On the way to Ithaka[1]: Commemorating the 50th Anniversary of the Publication of Karl E. Weick’sThe Social Psychology of Organizing
Authors: Tsoukas Haridimos , Patriotta Gerardo , Sutcliffe Kathleen M. , Maitlis Sally
Published: August 2020

Karl E. Weick’sThe Social Psychology of Organizinghas been one of the most influential books in organization studies, providing the theoretical underpinnings of several research programs. Importantly, the book is widely credited with initiating theprocess turnin the field, leading to the ‘gerundizing’ of management and organization studies: the persistent effort to understand organizational phenomena as ongoing accomplishments. The emphasis of the book on organizing (rather than on organizations) and its links with sensemaking have made it the most influential treatise on organizational epistemology. In this introduction, we review Weick’s magnum opus, underline and assess its key themes, and suggest ways in which several of them may be taken forward.
Social capital determinants and labor market networks
Authors: Asquith Brian , Hellerstein Judith K. , Kutzbach Mark J. , Neumark David
Published: August 2020

We explore the links between determinants of social capital and labor market networks at the neighborhood level. We harness rich data taken from multiple sources, including matched employer–employee data with which we measure the strength of labor market networks, data on neighborhood homogeneity that has previously been tied to social capital, and new data—not previously used in the study of social capital—on the number and location of nonprofit sector establishments at the neighborhood level. We use a machine learning algorithm to identify the potential determinants of social capital that best predict neighborhood‐level variation in labor market networks. We find evidence suggesting that smaller and less centralized schools, and schools with fewer poor students, foster social capital that builds local labor market networks, as does a larger Republican vote share. The presence of establishments in a number of nonprofit‐oriented industries are identified as predictive of strong labor market networks, likely because they either provide public goods or facilitate social contacts. These industries include, for example, churches and other religious institutions, fire and rescue services including volunteer fire departments, country clubs and golf courses, labor unions, chamber music groups, hobby clubs, and schools.
Interactive Effects of CO2, Temperature, Irradiance, and Nutrient Limitation on the Growth and Physiology of the Marine Diatom Thalassiosira pseudonana (Coscinodiscophyceae)
Authors: Laws Edward A. , McClellan S. Alex , Passow Uta
Published: August 2020

The marine diatom Thalassiosira pseudonana was grown in continuous culture systems to study the interactive effects of temperature, irradiance, nutrient limitation, and the partial pressure of CO2 (pCO2) on its growth and physiological characteristics. The cells were able to grow at all combinations of low and high irradiance (50 and 300 μmol photons · m−2 · s−1, respectively, of visible light), low and high pCO2 (400 and 1,000 μatm, respectively), nutrient limitation (nitrate‐limited and nutrient‐replete conditions), and temperatures of 10–32°C. Under nutrient‐replete conditions, there was no adverse effect of high pCO2 on growth rates at temperatures of 10–25°C. The response of the cells to high pCO2 was similar at low and high irradiance. At supraoptimal temperatures of 30°C or higher, high pCO2 depressed growth rates at both low and high irradiance. Under nitrate‐limited conditions, cells were grown at 38 ± 2.4% of their nutrient‐saturated rates at the same temperature, irradiance, and pCO2. Dark respiration rates consistently removed a higher percentage of production under nitrate‐limited versus nutrient‐replete conditions. The percentages of production lost to dark respiration were positively correlated with temperature under nitrate‐limited conditions, but there was no analogous correlation under nutrient‐replete conditions. The results suggest that warmer temperatures and associated more intense thermal stratification of ocean surface waters could lower net photosynthetic rates if the stratification leads to a reduction in the relative growth rates of marine phytoplankton, and at truly supraoptimal temperatures there would likely be a synergistic interaction between the stresses from temperature and high pCO2 (lower pH).
Pharmacokinetics and bioavailability of tildipirosin following intravenous and subcutaneous administration in sheep
Authors: Abu‐Basha Ehab A. , Bani Ismail Zuhair , Abu Alhaijaa Hind , Hamzeh Eyad , Idkaidek Nasir M.
Published: August 2020

Tildipirosin is a semi‐synthetic macrolide antibiotic commonly used in cattle and swine to treat bacterial pneumonia. The objective of this study was to investigate the pharmacokinetic profile of tildipirosin after a single intravenous (i.v.) and subcutaneous (s.c.) administration in healthy lambs. Eighteen lambs were randomly divided into three groups (n = 6 each). Lambs received a single s.c. dose of tildipirosin at 4 and 6 mg/kg b.w. in group 1 and 2, respectively. Lambs in group 3 received a single i.v. dose of tildipirosin at 4 mg/kg b.w. Blood samples were collected at 0, 0.5, 0.75, 1.5, 2, 3, 4, 6, 8, 10, 24, 36, 48 hr, and every 24 hr to day 21, and thereafter at day 28 posttildipirosin administration. The plasma concentrations of tildipirosin were determined using high‐performance liquid chromatography with tandem mass spectrometry detection (LC⁄MS⁄MS). All lambs appeared to tolerate both the intravenous and subcutaneous injection of tildipirosin. Following i.v. administration, the elimination half‐life (T1/2), mean residence time (MRT), volume of distribution (Vd/F), and total body clearance (Cl/F) were 119.6 ± 9.0 hr, 281.9 ± 25.7 hr, 521.1 ± 107.2 L, and 2.9 ± 0.5 L/hr, respectively. No significant differences in Cmax (657.0 ± 142.8 and 754.6 ± 227.1 ng/ml), Tmax (1.21 ± 0.38 and 1.35 ± 0.44 hr), T1/2 (144 ± 17.5, 156.5 ± 33.4 hr), and MRT (262.0 ± 30.2 and 250.6 ± 54.5 hr) were found in tildipirosin after s.c. dosing at 4 and 6 mg/kg b.w., respectively. The absolute bioavailability (F) of tildipirosin was 71.5% and 75.3% after s.c. administration of 4 and 6 mg/kg b.w., respectively. In conclusion, tildipirosin was rapidly absorbed and slowly eliminated after a single s.c. administration in healthy lambs. Tildipirosin could be used for the treatment and prevention of respiratory bacterial infections in sheep. However, further in vitro and in vivo studies to determine the efficacy and safety are warranted. To our knowledge, this is the first study to determine the tildipirosin pharmacokinetic parameters in sheep plasma.
Predictors of getting a residency interview: Differences by medical specialty
Authors: Kremer Theodore R. , Kremer Michael J. , Kremer Kristen P. , Mihalic Angela
Published: August 2020

Objectives

Gaining medical residency interviews has become more competitive and costly for medical students. Although limited evidence from residency programme directors indicates predictors for successfully matching into a programme, past research has not sufficiently explored the application components necessary to receive an interview offer. The present study will identify which application components are most helpful in obtaining interview offers for different medical specialties.

Methods

Data were sourced from the Texas Seeking Transparency in Application to Residency (STAR), a survey of recently matched fourth‐year American medical students who self‐reported information on their residency application components and interview offers. Multi‐level logistic regression analyses were employed to predict the odds of interview offer according to applicants’ academic, research and extracurricular characteristics. Sub‐analyses were conducted for each medical specialty.

Results

Nearly 10 000 students reported information on over 419 010 applications submitted, which resulted in 164 696 interview offers. Across the sample, applicants had greater odds of receiving an interview offer if they had a geographic connection to the programme (odds ratio [OR] = 4.10, 95% confidence interval [CI] 4.00‐4.20), had completed an away rotation at the programme (OR = 16.00, 95% CI 14.92‐17.15), were Alpha Omega Alpha Honor Medical Society members (OR = 1.49, 95% CI 1.36‐1.64), or had been inducted into the Gold Humanism Honor Society (OR = 1.50, 95% CI 1.39‐1.62). Applicants had reduced odds of getting an interview if they had been required to remediate a course in medical school (OR = 0.73, 95% CI 0.64‐0.83) or had failed the US Medical Licensing Examination Step 1 or Step 2 examination on their first attempt (OR = 0.40, 95% CI 0.33‐0.47). Predictors of obtaining an interview varied by specialty.

Conclusions

The present findings can assist senior medical students as they prepare residency applications and identify programmes to which they will apply. Knowledge of the significant factors can help applicants more efficiently use resources to maximise their number of interview offers. Completing away rotations and selecting programmes with which applicants have geographic connections may increase their odds of receiving interview offers.
Isolation of Aspergillus spp. in respiratory samples of patients with COVID‐19 in a Spanish Tertiary Care Hospital
Authors: Falces‐Romero Iker , Ruiz‐Bastián Mario , Díaz‐Pollán Beatriz , Maseda Emilio , García‐Rodríguez Julio ,   SARS‐CoV‐2 Working Group
Published: August 2020

Background

Invasive pulmonary aspergillosis (IPA) is a complication of respiratory bacterial and viral infections such as coronavirus disease 2019 (COVID‐19).

Patients/Methods

In University Hospital La Paz (Madrid, Spain), we reviewed the clinical and demographic characteristics of 10 patients with positive severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) PCR and Aspergillus spp. isolate in respiratory samples. We also recovered results of galactomannan tests in serum and/or bronchoalveolar lavage (BAL) samples.

Results

Eight male and two female from 51 to 76 years were recovered. They had reported risk factors to develop IPA (haematological malignancies, immunosuppression, diabetes, obesity, intensive care unit stay, among others). Azole susceptible Aspergillus fumigatus was isolated in nine patients and Aspergillus nidulans was isolated in one patient. Only one case was classified as probable aspergillosis, seven cases as putative aspergillosis, and two cases were not classifiable. Eight patients received antifungal treatment. Seven patients died (70%), two are still inpatient due to nosocomial infections and one was discharged referred to another institution.

Conclusions

This clinical entity has high mortality, and therefore, it should be performed surveillance with early galactomannan tests and cultures in respiratory samples in order to improve the outcome of the patients with this condition.
Servant Leadership, Third‐Party Behavior, and Emotional Exhaustion of Followers
Authors: Obi Innocentina‐Marie O. , Bollen Katalien , Aaldering Hillie , Robijn Wouter , Euwema Martin C.
Published: August 2020

Conflicts are ubiquitous in all life’s domain where people live and perform interdependent tasks, including convents. Managing conflicts among followers is an essential responsibility of leaders. The way leaders behave while managing such conflicts have received little academic attention; available studies have focused on business contexts. This study aimed to examine the relationship between servant leadership, and emotional exhaustion through team conflicts, and further investigates the mediating role of leaders’ third‐party conflict behaviors such as avoiding, forcing, and problem‐solving. Data were gathered from 453 religious sisters (followers), in 166 convents, in a Catholic Women Religious Institute mostly based in Nigeria. Structural equation modeling confirmed that servant leadership was associated with reduced team conflicts through leaders’ third‐party behaviors. Further findings showed that perceived servant leadership was negatively related to emotional exhaustion through a nonforcing expression. We discussed theoretical and practical implications.
Optimal sites for mini‐implant insertion in the lingual or palatal alveolar cortical bone as assessed by cone beam computed tomography in South Indian population
Authors: Mallick Soham , Murali P. S. , Kuttappa M. N. , Shetty Prajwal , Nair Aishwarya
Published: August 2020

Objectives

To determine the optimal sites of mini‐implant placement in the palatal alveolar cortical bone by using cone beam computed tomography (CBCT).

Subjects and Methods

Cone beam computed tomography records of 60 patients were divided into two groups of equal sizes, based on age and sex. The images were analysed using Planmeca Romexis Software (Version 4.1.2). The measurements were made in axial sections of the maxilla and mandible, at 2, 4 and 6 mm from the CEJ. The optimal sites were defined in terms of (a) Palatal or lingual alveolar cortical bone thickness and (b) Mesiodistal palatal or lingual inter‐radicular width.

Results

The optimal site for mini‐implant insertion, anteriorly, was the canine‐lateral incisor embrasure in both the jaws. Posteriorly, the inter‐molar embrasure in the mandible and the molar‐premolar embrasure in the maxilla were optimal sites. Females demonstrated significantly lesser bone widths in all areas of the maxilla (P < .05) but greater bone thickness in the mandibular regions, as compared to males. The adolescent age group demonstrated a significantly lesser bone thickness but greater mesiodistal widths than the adult population in both the jaws (P < .05).

Conclusion

The optimal sites for mini‐implant insertion were the anterior canine‐lateral incisor and posterior buccal inter‐radicular embrasures, in both the jaws. Significant differences existed between age and gender groups, which need to be kept in mind while choosing the locations for placing mini‐implants.
Delta brushes are not just a hallmark of EEG in human preterm infants
Authors: Kidokoro Hiroyuki
Published: August 2020

The delta brush, a well‐known characteristic waveform of the human preterm electroencephalogram, represents spontaneous electrical activity. Recent experimental animal model evidence suggests that delta brushes are not only spontaneous intrinsic activity but are also evoked by external sensory stimulation or spontaneous movement. They are also likely to reflect the activity of subplate neurons, which play an important role in early brain development and network organization. Here, evidence about delta brushes in human preterm electroencephalogram is provided along with future perspectives.
Talking Policy in Congressional Campaigns: Construction of Policy Narratives in Electoral Politics
Authors: Crow Deserai , Wolton Laura
Published: August 2020

The construction of narratives to influence policy decisions has garnered increased scholarly attention over the past decade as use of the Narrative Policy Framework (NPF) has expanded in the policy literature. However, we do not know whether policy narratives as defined by the NPF are present in electoral communications or whether there are significant differences in construction of such narratives. Narratives from both Republican and Democratic campaigns in 48 U.S. House campaigns are analyzed in this study, using an automated coding approach to determine whether policy narratives also exist within electoral campaigns, whether they hold similar structures, and whether there are significant differences according to candidate characteristics. We find that electoral policy narratives do hold consistent form and two significant narrative differences exist: (1) policy issues discussed vary based on candidate characteristics such as gender and political affiliation; and (2) character portrayal varies based on party affiliation and gender of the candidate.

Related Articles

Crow, Deserai A., Lydia A. Lawhon, John Berggren, Juhi Huda, Elizabeth Koebele, and Adrianne Kroepsch. 2017. “A Narrative Policy Framework Analysis of Wildfire Policy Discussions in two Colorado Communities.” Politics & Policy 45 (4): 626‐656. https://doi.org/10.1111/polp.12207

Ertas, Nevbahar. 2015. “Policy Narratives and Public Opinion Concerning Charter Schools.” Politics & Policy 43 (3): 426‐451. https://doi.org/10.1111/polp.12120

Shanahan, Elizabeth A., Mark K. McBeth, and Paul L. Hathaway. 2011. “Narrative Policy Framework: The Influence of Media Policy Narrative on Public Opinion.” Politics & Policy 39 (3): 373‐400. https://doi.org/10.1111/j.1747-1346.2011.00295.x
Risk‐Sensitive Markov Decision Processes with Combined Metrics of Mean and Variance
Authors: Xia Li
Published: August 2020

This study investigates the optimization problem of an infinite stage discrete time Markov decision process (MDP) with a long‐run average metric considering both mean and variance of rewards together. Such performance metric is important since the mean indicates average returns and the variance indicates risk or fairness. However, the variance metric couples the rewards at all stages, the traditional dynamic programming is inapplicable as the principle of time consistency fails. We study this problem from a new perspective called the sensitivity‐based optimization theory. A performance difference formula is derived and it can quantify the difference of the mean‐variance combined metrics of MDPs under any two different policies. The difference formula can be utilized to generate new policies with strictly improved mean‐variance performance. A necessary condition of the optimal policy and the optimality of deterministic policies are derived. We further develop an iterative algorithm with a form of policy iteration, which is proved to converge to local optima both in the mixed and randomized policy space. Specially, when the mean reward is constant in policies, the algorithm is guaranteed to converge to the global optimum. Finally, we apply our approach to study the fluctuation reduction of wind power in an energy storage system, which demonstrates the potential applicability of our optimization method.
Capacity Investment, Production Flexibility, and Capital Structure
Authors: Ritchken Peter , Wu Qi
Published: August 2020

Many manufacturing firms have become increasingly flexible in that they can rapidly idle and restart production in response to changing commodity prices. We study how operational flexibility alters both the timing and financing decisions in the firm. We perform this analysis in a dynamic model in which a firm has multiple debt issues and decisions are made to maximize shareholder value. We compare the decisions of a flexible firm, which can temporarily shut down to avoid operational losses, with those of a rigid firm which is not able to stop operating even in states where operational losses occur. On one hand, firms with operational flexibility can better exploit a larger tax shield by taking on more debt. On the other hand, taking on more debt may be less harmful for a rigid firm, since it increases the default threshold thereby reducing the region where operational losses are experienced due to inflexibility. We explore how the two forces trade off between the benefit of tax shield and the cost of default. We find that, even though bondholders charge a higher fair premium for debt issued by the inflexible firm, the rigid firm will utilize more debt. We also show that, all things being equal, firms with operational flexibility invest earlier and use less debt to finance the opportunity. Dynamic models that trade off tax shields with bankruptcy costs and ignore operational flexibility may result in theoretical leverage ratios being biased high.
Inconsistent analytic strategies reduce robustness in fear extinction via skin conductance response
Authors: Ney Luke John , Laing Patrick A.F. , Steward Trevor , Zuj Daniel V. , Dymond Simon , Felmingham Kim L.
Published: August 2020

Robustness of fear conditioning and extinction paradigms has become increasingly important for many researchers interested in improving the study of anxiety and trauma disorders. We recently illustrated the wide variability in data analysis techniques in this paradigm, which we argued may result in a lack of robustness. In the current study, we resampled data from six of our own fear acquisition and extinction data sets, with skin conductance as the outcome. In the resampled and original data sets, we found that effect sizes that were calculated using discrepant statistical strategies, sourced from a non‐exhaustive search of high‐impact articles, were often poorly correlated. The main contributors to poor correlations were the selection of trials from different stages of each experimental phase and the use of average compared to trial‐by‐trial analysis. These findings reinforce the importance of focusing on robustness in the psychophysiological measurement of fear acquisition and extinction in the laboratory and may guide prospective researchers in which decisions may most impact the robustness of their results.
Cerebral mechanisms of hypnotic hypoesthesia. An ERP investigation on the expectancy stage of perception
Authors: Perri Rinaldo Livio , Facco Enrico , Quinzi Federico , Bianco Valentina , Berchicci Marika , Rossani Francesco , Di Russo Francesco
Published: August 2020

The present study aims at identifying reliable markers of neural preparatory processes during hypnosis. To this goal, we recorded the electroencephalographic activity of 23 volunteers regardless of their hypnotizability score. Somatosensory evoked potentials (SEPs) were elicited while participants received non‐painful electrical stimuli on the left median nerve in the conditions of relaxation and hypnosis with suggestions of reduced sensation. SEPs analysis was focused on the pre‐stimulus activity and revealed two main components: the prefrontal negativity (pN) and the somatosensory negativity (sN) over the frontal and parietal areas of the scalp, respectively. Results showed reduced amplitudes for both components under hypnosis, mostly for the pN, suggesting a change of top‐down control of parietal and prefrontal areas. Furthermore, the sLORETA source imaging showed a deactivation of the lateral and anterior portions of the prefrontal cortex (PFC) during the hypnotic state. The present study highlights the downregulation of the PFC as a core aspect of the adopted hypnotic task and confirms the ability of hypnosis to modulate the activity of frontal executive functions. Further, since the majority of participants fell into the medium range of hypnotizability, the present findings could reflect the hypnosis effects in most of the population.
Interindividual differences in brain dynamics of early visual processes: Impact on score accuracy in the mental rotation task
Authors: Ruggeri Paolo , Nguyen Nam , Pegna Alan J. , Brandner Catherine
Published: August 2020

Interindividual variations in the ability to perform visuospatial mental transformations have been investigated extensively, in particular through mental rotation tasks. However, the impact of early visual processes on performance has been largely ignored. To clarify this issue, we explored the time‐course of early visual processing (from 0 to 450 ms poststimulus) using event‐related potentials topographic analyses. The main findings demonstrated a significant link between early attentional processes and accuracy scores occurring more than five seconds later, as well as a strong association between spatial covariance and microstate topographies exhibiting substantial gender differences. More specifically, the results indicated that, in a classical mental rotation task, the male brain expends more time processing visual‐spatial information resulting in a longer bilateral positive potential at posterior‐occipital sites. In comparison, the female brain initiates earlier processing of non‐spatial information resulting in a faster transition from a bilateral positive potential of posterior‐occipital sites to a negative potential at central‐frontal sites. These findings illustrate how a more complete utilization of the spatiotemporal information contained in EEG recordings can provide important insights about the impact of early visual processes on interindividual differences, particularly across gender, and thus shed new light on alternate cognitive strategies.
Neuromuscular determinants of explosive torque: Differences among strength‐trained and untrained young and older men
Authors: Orssatto Lucas B. R. , Wiest Matheus J. , Moura Bruno M. , Collins David F. , Diefenthaeler Fernando
Published: August 2020

This study compared the differences in neural and muscular mechanisms related to explosive torque in chronically strength‐trained young and older men (>5 years). Fifty‐four participants were allocated into four groups according to age and strength training level: older untrained (n = 14; 65.6 ± 2.9 years), older trained (n = 12; 63.6 ± 3.8 years), young untrained (n = 14; 26.2 ± 3.7 years), and young trained (n = 14; 26.7 ± 3.4 years). Knee extension isometric voluntary explosive torque (absolute and normalized as a percentage of maximal voluntary torque) was assessed at the beginning of the contraction (ie, 50, 100, and 150 ms—T50, T100, and T150, respectively), and surface electromyogram (sEMG) amplitude (normalized as a percentage of sEMG recorded during maximal voluntary isometric contraction) at 0‐50, 50‐100, and 100‐150 time windows. Supramaximal electrically evoked T50 was assessed with octet trains delivered to the femoral nerve (8 pulses at 300 Hz). Voluntary T50, T100, and T150 were higher for trained than untrained in absolute (P < 0.001) and normalized (P < 0.030) terms, accompanied by higher sEMG at 0‐50, 50‐100, and 100‐150 ms (P < 0.001), and voluntary T50/octet T50 ratio for trained. Greater octet T50 was observed for the young trained (P < 0.001) but not for the older trained (P = 0.273) compared to their untrained counterparts. Age effect was observed for voluntary T50, T100, and T150 (P < 0.050), but normalization removed these differences (P > 0.417). Chronically strength‐trained young and older men presented a greater explosive torque than their untrained pairs. In young trained, the greater explosive performance was attributed to enhanced muscular and neural mechanisms, while in older trained to neural mechanisms only.
Preclinical evaluation for removal of bulging lower eyelid fat using ultrasound‐assisted lipolysis on a Yorkshire pig
Authors: Yoo Kwang Ho , Kwon Tae Rin , Kim Jong Hwan , Kim Beom Joon
Published: August 2020

Purpose

The purpose of this study is to evaluate the efficacy and safety of treating lower eyelid fat bulging with ultrasound‐assisted lipolysis (UAL) by performing a preclinical evaluation of the procedure on a Yorkshire pig.

Methods

Two white Yorkshire pigs had lower eyelid fat bulging treated with UAL using a probe with a diameter of 1.0 mm or less. Fourteen days after treatment, we evaluated the changes in fat thickness from ultrasound, changes in skin contour (volume and height) from the Antera 3D™, and the disruption of fat cells and changes in collagen synthesis from histological evaluation.

Results

Fourteen days after treatment, the fat layer was significantly reduced with no damage to the skin surface. The mean change in the subcutaneous fat layer thickness was decreased 1.51‐0.75 mm in ultrasound analysis. The skin contour of the treated area also decreased with time from 202.5 to 163.5 mm in mean volume and 0.8111 to 0.646 mm in mean height. Masson's trichrome staining showed that the UAL treatment induced the regeneration and remodeling of collagen.

Conclusion

The results of this study demonstrate that UAL successfully reduced the bulging lower eyelid fat of a Yorkshire pig and also increased collagen contraction to tighten skin. UAL may be a beneficial and well‐tolerated treatment option for lower eyelid fat bulging.
Advances in analysis of total uncertainties in a semi‐invasive residual stress measurement method
Authors: Hossain Sayeed , Zheng Gang , Goudar Devkumar
Published: August 2020

The ability to characterise residual stress distribution accurately and over different length scales, particularly deep into an engineering part, plays a significant role in assessing structural integrity. Two most commonly used techniques to measure residual stress fields deep into engineering components include neutron diffraction (ND) and deep‐hole drilling (DHD). As the measurements depend on several physical quantities, they are susceptible to error. The error or uncertainties may turn substantial and compromise the suitability of the results. Although noninvasive, the neutron diffraction technique is neither readily available nor portable and is limited to approximately 60‐mm‐thick specimen; errors associated with results become unacceptable at greater flight paths. Moreover, a mock‐up representing the engineering component is normally used in the ND technique. In contrast, the DHD technique is portable and measures residual stresses with high spatial resolution. An error propagation technique was applied to develop an error analysis procedure taking into consideration various stages of the DHD method and successfully applied to different DHD measurements. An essential feature comprising the effect of plasticity due to the creation of reference hole in the DHD procedure has not yet been taken into account in the error analysis procedure. This paper briefly describes how the uncertainties due to the creation of the initial reference hole can be determined. The effect of plasticity in the drilling procedure is quantified in this study. This error is combined with other sources of error and formulated to determine the total error. An incremental DHD technique was used to measure the complex triaxial residual stress field in an as‐welded circular disc, and the measured data were used to illustrate the total error using the error analysis method developed in the study.
Self‐limited HBV infection of the recipient does not reactivate after liver transplantation: Observations from a 30‐year liver transplant program
Authors: Ossami Saidy R.R. , Demir Muenevver , Nibbe Pauline , Dobrindt Eva‐Maria , Oellinger Robert , Schoening Wenzel , Pratschke Johann , Eurich Dennis
Published: August 2020

Background

A self‐limited hepatitis B infection can reactivate in patients under immunosuppression or chemotherapy (reappearance of hepatitis B surface antigen (HBsAg) or HBV‐DNA). Exact circumstances of HBV reactivation in patients undergoing liver transplantation (LT) for end‐stage liver diseases (ESLD) unrelated to HBV are unknown, and recommendations on HBV prophylaxis remain unclear.

Patients and methods

Among 1273 liver transplants, 168 patients with a self‐limited HBV hepatitis B infection prior to LT were identified from our prospective liver transplant database. Patients with underlying chronic HBV infection and recipients of an anti‐HBc‐positive liver were not included in the analysis. Demographic, laboratory, serological, and virological data were analyzed retrospectively. Appearance of HBsAg or HBV‐DNA was defined as reactivation.

Results

The median follow‐up after LT was 12.0 years (0.6‐30.7 years). The rate of HBV reactivation was 0% independent of antiviral prophylaxis (n = 7; 4.2%), the etiology of ESLD, hepatitis C treatment, or the anti‐HBs concentration. The overall patient survival with a history of a self‐limited HBV infection before LT did not significantly differ from the rest of the cohort.

Conclusion

Antiviral treatment with nucleos(t)ide analogues post‐liver transplantation in order to prevent HBV reactivation in patients with a resolved self‐limited hepatitis B infection prior to LT seems to be omittable since the main viral reservoir is removed by the hepatectomy. These findings may clarify the current uncertainty in the recommendations regarding the risk of HBV reactivation in patients with self‐limited hepatitis B prior to LT.
Epidural stimulation for cardiovascular function increases lower limb lean mass in individuals with chronic motor complete spinal cord injury
Authors: Legg Ditterline Bonnie , Harkema Susan J. , Willhite Andrea , Stills Sean , Ugiliweneza Beatrice , Rejc Enrico
Published: August 2020

New Findings

What is the central question of this study?

Spinal cord injury results in paralysis and deleterious neuromuscular and autonomic adaptations. Lumbosacral epidural stimulation can modulate motor and/or autonomic functions. Does long‐term epidural stimulation for normalizing cardiovascular function affect leg muscle properties?

What is the main finding and its importance?

Leg lean mass increased after long‐term epidural stimulation for cardiovascular function, which was applied in the sitting position and did not activate the leg muscles. Leg muscle strength and fatigue resistance, assessed in a subgroup of individuals, also increased. These adaptations might support interventions for motor recovery and warrant further mechanistic investigation.

Chronic motor complete spinal cord injury (SCI) results in paralysis and deleterious neuromuscular and autonomic adaptations. Paralysed muscles demonstrate atrophy, loss of force and increased fatigability. Also, SCI‐induced autonomic impairment results in persistently low resting blood pressure and heart rate, among other features. We previously reported that spinal cord epidural stimulation (scES) optimized for cardiovascular (CV) function (CV‐scES), which is applied in sitting position and does not activate the leg muscles, can maintain systolic blood pressure within a normotensive range during quiet sitting and during orthostatic stress. In the present study, dual‐energy X‐ray absorptiometry collected from six individuals with chronic clinically motor complete SCI demonstrated that 88 ± 11 sessions of CV‐scES (7 days week−1; 2 h day−1 in four individuals and 5 h day−1 in two individuals) over a period of ∼6 months significantly increased lower limb lean mass (by 0.67 ± 0.39 kg or 9.4 ± 8.1%; P < 0.001). Additionally, muscle strength and fatigability data elicited by neuromuscular electrical stimulation in three of these individuals demonstrated a general increase (57 ± 117%) in maximal torque output (between 2 and 44 N m in 14 of the 17 muscle groups tested overall) and torque–time integral during intermittent, fatiguing contractions (63 ± 71%; between 7 and 230% in 16 of the 17 muscle groups tested overall). In contrast, whole‐body mass and composition did not change significantly. In conclusion, long‐term use of CV‐scES can have a significant impact on lower limb muscle properties after chronic motor complete SCI.
Building of AMPA‐type glutamate receptors in the endoplasmic reticulum and its implication for excitatory neurotransmission
Authors: Schwenk Jochen , Fakler Bernd
Published: August 2020

AMPA‐type glutamate receptors (AMPARs), the key elements of fast excitatory neurotransmission in the brain, are receptor ion channels whose core is assembled from pore‐forming and three distinct types of auxiliary subunits. While it is well established that this assembly occurs in the endoplasmic reticulum (ER), it has remained largely enigmatic how this receptor‐building happens. Here we review recent findings on the biogenesis of AMPARs in native neurons as a multistep production line that is defined and operated by distinct ER‐resident helper proteins, and we discuss how impairment of these operators by mutations or targeted gene‐inactivation leads to severe phenotypes in both humans and rodents. We suggest that the recent data on AMPAR biogenesis provide new insights into a process that is key to the formation and operation of excitatory synapses and their activity‐dependent dynamics, as well as for the operation of the mammalian brain under normal and pathological conditions.

image
Surface kinetics and feature scale particle model of SixNy atomic layer deposition using Si2Cl6 precursor
Authors: Solmaz Evrim , Ryu Seung-Min , Uh Jiho , Raja Laxminarayan L.
Published: August 2020

One of the important steps in the fabrication of semiconductor memory devices is the deposition of ultrathin silicon nitride films with uniform film thickness and electrical properties. Such high-quality films have made atomic level control during deposition a necessity and can be achieved via atomic layer deposition (ALD) with excellent step coverage. While ALD has been studied experimentally by many authors, there exist significant gaps between their observations and the practical application of the ALD process in large-scale manufacturing. In this work, a computational model of thin film deposition for a silicon based ALD application was developed. The model includes a surface chemistry mechanism for the deposition of hexachlorodisilane (Si2Cl6) on a growing SixNy film. This mechanism quantifies the sticking probability of the Si2Cl6 precursor on the growth surface as well as an effective active reaction site density on these surfaces. This surface reaction chemistry was used in the context of a feature scale particle transport model to simulate ALD in 100 nm–1 μm critical dimension, ∼10–100 high aspect ratio holes. The model demonstrates the effects of hole size and aspect ratio dependence on the overall kinetics of the deposition process. An increase in the completion time for ALD processes with increasing hole aspect ratio and the increasing statistical nature of the deposition process with smaller critical dimension of the hole were predicted.