bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of mindfulness‐based intervention on glycemic control and psychological outcomes in people with diabetes: A systematic review and meta‐analysis
Authors: Ni Yun‐xia , Ma Lin , Li Ji‐ping
Published: October 2020

Aims/Introduction

Psychological therapies have showed benefits for both glycemic control and psychological outcomes in people with diabetes. However, the effects of mindfulness‐based intervention (MBI) on glycemic control and psychological outcomes are inconsistent across studies, and the evidence for MBI has not been summarized. We aimed to identify the effects of MBI on glycemic control and psychological outcomes in people with diabetes by carrying out a systematic review and meta‐analysis.

Materials and Methods

Six databases (Pubmed, Embase, CINAHL, Cochrane, Web of science and PsycINFO) were searched from inception to October 2019. Randomized controlled trials of MBI for people with type 1 and type 2 diabetes were included. Two authors independently extracted relevant data and assessed the risk of bias, with a third reviewer as arbitrator. Subgroup analyses and sensitivity analyses were also carried out.

Results

Eight studies with 841 participants met the eligibility criteria. Meta‐analysis showed that MBI can slightly improve glycosylated hemoglobin (HbA1c; −0.25%, 95% confidence interval [CI] −0.43 to −0.07) and diabetes‐related distress (−5.81, 95% CI −10.10 to −1.52) contribute to a moderate effect size in reducing depression (standardized mean difference −0.56, 95% CI −0.82 to −0.30) and stress (standardized mean difference −0.53, CI −0.75 to −0.31). Subgroup analyses showed greater HbA1c reductions in subgroups with baseline HbA1c levels <8% and follow‐up duration >6 months. Mixed effects were observed for anxiety.

Conclusions

MBI appears to have benefits on HbA1c, depression, stress and diabetes‐related distress in people with diabetes. More rigorous studies with longer follow‐up duration are warranted to establish the full potential of MBI.
Differences among the forelimb arteries in groups of primates and a mathematical model explanation
Authors: Aversi‐Ferreira Tales Alexandre , Freitas‐Ferreira Emmanuel , Aversi‐Ferreira Roqueline A. G. M. F.
Published: October 2020

Background

Recently, some studies about primates have claimed the importance of the vessels to maintain the muscles working; in fact, the arterial supply could suggest how strenuous the muscular performance is associated to locomotor behavior. The aim of this work was to study the anatomy of the arteries of the forelimbs of different groups of primates to evidence a general arterial model in comparative terms.

Methods

We propose a biophysical explanation for the arterial pattern of the forelimbs of primates’ groups.

Results

Three pattern of the forelimb arteries in Primates were descript and the differences were explained using mathematical formulas.

Conclusions

The anatomical study about the comparative anatomy of the arteries of the forelimbs of primates provided hypothesis about the three observed models, mainly in relation to brachial artery division and the number of the palmar arches, in mathematical models’ terms.
Ghrelin signalling is dysregulated in male but not female offspring in a rat model of maternal vertical sleeve gastrectomy
Authors: Spann Redin A. , Welch Bradley A. , Grayson Bernadette E.
Published: October 2020

Bariatric surgery is the most effective and durable means of treating obesity and its comorbidities. Women make up 80% of those receiving weight loss surgery and they experience improvements in fertility. Unfortunately, bariatric surgery in the context of pregnancy is associated with complications, including growth restriction and small‐for‐gestational age offspring (SGA). SGA offspring have a greater risk for obesity in adulthood, although the mechanism for this SGA‐induced obesity is unknown. In a rat model of vertical sleeve gastrectomy (VSG), we previously identified reductions during pregnancy in ghrelin, a stomach‐derived hormone that increases appetite and induces growth hormone secretion. Here, we hypothesise that VSG offspring will have altered ghrelin signalling compared to offspring of Sham dams as a result of reduced in utero ghrelin. At postnatal day (PND)21, male and female offspring of dams that have previously received VSG have an increase in mRNA expression for the ghrelin receptor in the hypothalamus compared to Sham offspring, and the expression of GOAT is lower in females compared to males. Liver expression of endogenous ghrelin antagonist, LEAP2, is elevated at PND60 in VSG offspring. Expression of other genes in the growth hormone system (growth hormone‐releasing hormone and growth hormone) were not altered. Plasma levels of total ghrelin at PND21 are also not different between VSG and Sham pups. In adult pups, 1‐hour chow intake of male but not female VSG offspring given is less than Sham offspring when given 50 µg kg‐1 of exogenous ghrelin by i.p. injection. These results indicate that maternal VSG surgery has an impact on ghrelin signalling in offspring and that, as adults, male VSG offspring may be functionally less responsive to ghrelin than controls.
Nationwide survey of Japanese breast oncology and reproductive endocrinology departments about the impact of breast cancer treatment on fertility
Authors: Yamazaki Rena , Ono Masanori , Sugie Tomoharu , Inokuchi Masafumi , Ishikawa Satoko , Iizuka Takashi , Masumoto Sakiko , Myojo Subaru , Uchida Soko , Horie Akihito , Matsuzaki Toshiya
Published: October 2020

The purpose of this study is to assess the impact of breast cancer treatment on the reproductive potential. We conducted a nationwide survey of breast oncology and reproductive endocrinology and infertility (REI) departments using a questionnaire designed to assess the impact of breast cancer treatment on fertility. We received responses from 312 breast oncology departments (response rate, 31.9%) and 541 REI departments (response rate, 50.9%). The most common method of achieving pregnancy reported by breast oncology departments was natural insemination (69.6%), followed by assisted reproductive technology ( 15.6%) and intrauterine insemination (IUI; 14.8%). The most common method of achieving pregnancy reported by REI departments was conventional in vitro fertilization and/or intracytoplasmic sperm injection (51.0%), followed by natural insemination with or without ovulation induction (40.0%) and IUI (8.0%). The overall pregnancy rate for patients who underwent treatment for infertility at REI departments after breast cancer treatment was 39.0%. Vast patients who experienced breast cancer treatments conceived mainly by natural insemination based on the data from breast oncology departments. On the other hand, 61.0% of the patients who visited REI departments presumably due to infertility by natural insemination did not conceive even by infertility treatments with exclusive knowledge in REI departments.
Outdoor infrared imaging for spatial and temporal thermography: A case study of necrotic versus healthy leaf areas on woody plants
Authors: Park Junhyung , Kim Ki Woo
Published: October 2020

The temperature of plants can be measured using infrared (IR) thermography. Despite the extensive use of IR imaging indoors, outdoor IR imaging is uncommon. We used IR imaging to compare leaf temperatures between necrotic spots and healthy areas of oriental cherry (Prunus serrulata var. spontanea), Japanese cornel (Cornus officinalis) and sawtooth oak (Quercus acutissima) in the field. There was a significant difference in the mean leaf temperatures between the necrotic spots (26.4°C) and healthy areas (25.6°C) of oriental cherry (p = .01). The mean temperatures in the necrotic spots of Japanese cornel and sawtooth oak leaves were 22.3°C and 29.6°C, respectively, which were not significantly different from the mean temperatures of the healthy areas. A consecutive, 2‐day temporal leaf analysis in October 2018 revealed that the temperatures in the necrotic spots were generally higher than those in the healthy areas of the three species. The temperature difference between the spots and healthy areas (up to 1.4°C) was more pronounced at 13:00 hr in all three species on both days. These results reveal differences in the spatial and temporal thermal state across the necrotic spotted leaves. There is potential for use of outdoor IR imaging to visualize the response of trees to pathogen infection and abiotic stress.
A critical realist perspective on humanness as a meaningful re‐entry of relational distinctions
Authors: Donati Pierpaolo
Published: October 2020

All forms of humanism that consider the human as a yardstick of society are marginalized by a Digital Technological Matrix that dominates the human, minimizes its role, and transforms it, to the point of dissolving its boundaries with the non‐human. Speaking of essence and human dignity still make sense? The thesis of this contribution is that the human is redefined and re‐evaluated precisely due to the process that makes the human ‘eccentric’ and places it in the system environment. The human re‐emerges as anintransitive essenceendowed with anoriginal, humble, relational dignity. The human can and must be regenerated through the relational reflexivity operated by relational subjects contextually capable of re‐entering within themselves the constitutive distinctions of their humanness, both individual and collective. The specific ‘intransitive’ essence of the human lies in the impossibility for it to renounce the meaning of its own existence. Precisely because of the confrontation with robotic technologies, the value of the human being and his dignity change.
Cost‐effectiveness analysis of sofosbuvir and velpatasvir in chronic hepatitis C patients with decompensated cirrhosis
Authors: Chan Jocelyn , Kim John J. , Barrett Brett K. , Hamadeh Abdullah , Feld Jordan J. , Wong William W.L.
Published: October 2020

Background

Current literature indicates that direct‐acting antivirals (DAAs) are cost‐effective to treat compensated cirrhotic patients with hepatitis C. Although already funded by public payers, it is unknown whether it is economical to reimburse DAAs within the more advanced decompensated cirrhosis population.

Methods

A state‐transition model was developed to conduct a cost‐utility analysis of sofosbuvir‐velpatasvir (SOF/VEL) plus ribavirin regimen for 12 weeks. The evaluated cohort had a mean age of 58 years and Child‐Turcotte‐Pugh (CTP) class B cirrhosis with decompensated symptoms. A scenario analysis was performed on CTP C patients. We used a payer perspective, a lifetime time horizon and a 1.5% annual discount rate.

Results

While SOF/VEL plus ribavirin treatment for 12 weeks increased costs by $156 676, it provided an extra 4.00 quality‐adjusted life years (QALYs) compared to best supportive care (no DAA therapy). With an incremental cost‐effectiveness ratio of $39 169 per QALY, SOF/VEL plus ribavirin was determined to be cost‐effective at a willingness to pay of $50 000 per QALY. SOF/VEL reduced liver‐related deaths and reduced progression to CTP C cirrhosis by 20.4% and 21.9%, respectively. On the contrary, SOF/VEL regimen resulted in increases in liver transplants and hepatocellular carcinoma (HCC) by 54.0% and 42.5%, respectively. Similar results were found for CTP C patients.

Conclusion

This analysis informs payers that SOF/VEL should continue to be reimbursed in decompensated hepatitis C patients. It also supports the recommendations by the American Association for the Study of Liver Diseases to continue screening for HCC in decompensated cirrhotic patients who have achieved sustained virologic response.
The bioavailability and pharmacokinetics of an amoxicillin–clavulanic acid granular combination after intravenous and oral administration in swine
Authors: Sun Pan , Zhao Tingting , Xiao Hongzhi , Wang Jie , Zhang Suxia , Cao Xingyuan
Published: October 2020

The pharmacokinetic behaviours of amoxicillin (AMX) and clavulanic acid (CA) in swine were studied after either an intravenous or oral administration of AMX (10 mg/kg) and CA (2.5 mg/kg). The concentrations of these two medicines in swine plasma were determined using high‐performance liquid chromatographic‐tandem mass spectrometry, and the data were analysed using a noncompartmental model with the WinNonlin software. After intravenous administration, both substances were absorbed rapidly and reached their effective therapeutic concentration quickly. CA was eliminated more slowly compared with AMX. Moreover, the distribution volume of AMX was larger than that of CA, suggesting that AMX could penetrate tissues better. After oral administration of the granular formulation, no significant difference was observed in the mean elimination half‐life value between AMX and CA. The mean maximal plasma concentrations of AMX and CA, reached after 1.14 and 1.32 hr, were 2.58 and 1.91 μg/m, respectively. The mean oral bioavailability of AMX and CA was 23.6% and 26.4%, respectively. After oral administration, the T>MIC50 for three common respiratory pathogens was over 6.12 hr. Therefore, oral administration could be more effective in the clinical therapy of pigs, especially when administered twice daily.
Hepatocyte‐derived MANF alleviates hepatic ischaemia‐reperfusion injury via regulating endoplasmic reticulum stress‐induced apoptosis in mice
Authors: Yang Yi , Wang Peng , Zhang Chaoyi , Huang Fan , Pang Gaozong , Wei Chuansheng , Lv Changming , Chhetri Goma , Jiang Tongcui , Liu Jun , Shen Yujun , Shen Yuxian
Published: October 2020

Background

Endoplasmic reticulum (ER) perturbations are novel subcellular effectors involved in the ischaemia‐reperfusion injury. As an ER stress‐inducible protein, mesencephalic astrocyte‐derived neurotrophic factor (MANF) has been proven to be increased during ischaemic brain injury. However, the role of MANF in liver ischaemia reperfusion (I/R) injury has not yet been studied.

Methods

To investigate the role of MANF in the process of liver ischaemia‐reperfusion, Hepatocyte‐specific MANF knockout (MANFhep−/−) mice and their wild‐type (WT) littermates were used in our research. Mice partial (70%) warm hepatic I/R model was established by vascular occlusion. We detected the serum levels of MANF in both liver transplant patients and WT mice before and after liver I/R injury. Recombinant human MANF (rhMANF) was injected into the tail vein before 1 hour occlusion. AST, ALT and Suzuki score were used to evaluate the extent of I/R injury. OGD/R test was performed on primary hepatocytes to simulate IRI in vitro. RNA sequence and RT‐PCR were used to detect the cellular signal pathway activation while MANF knockout.

Results

We found that MANF expression and secretion are dramatically up‐regulated during hepatic I/R. Hepatocyte‐specific MANF knockout aggravates the I/R injury through the over‐activated ER stress. The systemic administration of rhMANF before ischaemia has the potential to ameliorate I/R‐triggered UPR and liver injury. Further study showed that MANF deficiency activated ATF4/CHOP and JNK/c‐JUN/CHOP pathways, and rhMANF inhibited the activation of the two proapoptotic pathways caused by MANF deletion.

Conclusion

Collectively, our study unravels a previously unknown relationship among MANF, UPR and hepatic I/R injury.
Terlipressin has stood the test of time: Clinical overview in 2020 and future perspectives
Authors: Kulkarni Anand V. , Arab Juan Pablo , Premkumar Madhumita , Benítez Carlos , Tirumalige Ravikumar Sowmya , Kumar Pramod , Sharma Mithun , Reddy Duvvuru Nageshwar , Simonetto Douglas A. , Rao Padaki Nagaraja
Published: October 2020

Vasoactive drugs form the mainstay of therapy for two of the most important complications of liver disease: hepatorenal syndrome (HRS) and acute variceal bleed (AVB). With cumulative evidence supporting the use in cirrhosis, terlipressin has been recommended for the management of HRS and AVB. However, owing to the safety concerns, terlipressin was not approved by food and drug administration (FDA) until now. In this review, we discuss the pharmacology and the major practice‐changing studies on the safety and efficacy of terlipressin in patients with cirrhosis particularly focusing on existing indications like AVB and HRS and reviewing new data on the expanding indications in liver disease. The references for this review were identified from PUBMED with MeSH terms such as “terlipressin,” “hepatorenal syndrome,” “varices, esophagal and gastric,” “ascites” and “cirrhosis.” Terlipressin, a synthetic analogue of vasopressin, was introduced in 1975 to overcome the adverse effects of vasopressin. Terlipressin is an effective drug for HRS reversal in patients with liver cirrhosis and acute‐on‐chronic liver failure. There is documented mortality benefit with terlipressin therapy in HRS and AVB. Adverse effects are common with terlipressin and need to be monitored strictly. There is some evidence to support the use of this drug in refractory ascites, hepatic hydrothorax, paracentesis‐induced circulatory dysfunction and perioperatively during liver transplantation. However, terlipressin is not yet recommended for such indications. In conclusion, terlipressin has stood the test of time with expanding indications and clear prerequisites for clinical use. Our review warrants a fresh perspective on the efficacy and safety of terlipressin.
Convergence of utility indifference prices to the superreplication price in a multiple‐priors framework
Authors: Blanchard Romain , Carassus Laurence
Published: October 2020

This paper formulates a utility indifference pricing model for investors trading in a discrete time financial market under nondominated model uncertainty. Investor preferences are described by possibly random utility functions defined on the positive axis. We prove that when the investors's absolute risk aversion tends to infinity, the multiple‐priors utility indifference prices of a contingent claim converge to its multiple‐priors superreplication price. We also revisit the notion of certainty equivalent for multiple‐priors and establish its relation with risk aversion.
Newly discovered cichlid fish biodiversity threatened by hybridization with non‐native species
Authors: Blackwell Tabitha , Ford Antonia G. P. , Ciezarek Adam G. , Bradbeer Stephanie J. , Gracida Juarez Carlos A. , Smith Alan M. , Ngatunga Benjamin P. , Shechonge Asilatu , Tamatamah Rashid , Etherington Graham , Haerty Wilfried , Di Palma Federica , Turner George F. , Genner Martin J.
Published: October 2020

Invasive freshwater fishes are known to readily hybridize with indigenous congeneric species, driving loss of unique and irreplaceable genetic resources. Here we reveal that newly discovered (2013–2016) evolutionarily significant populations of Korogwe tilapia (Oreochromis korogwe) from southern Tanzania are threatened by hybridization with the larger invasive Nile tilapia (Oreochromis niloticus). We use a combination of morphology, microsatellite allele frequencies and whole genome sequences to show that O. korogwe from southern lakes (Nambawala, Rutamba and Mitupa) are distinct from geographically disjunct populations in northern Tanzania (Zigi River and Mlingano Dam). We also provide genetic evidence of O. korogwe × niloticus hybrids in three southern lakes and demonstrate heterogeneity in the extent of admixture across the genome. Finally, using the least admixed genomic regions we estimate that the northern and southern O. korogwe populations most plausibly diverged ~140,000 years ago, suggesting that the geographical separation of the northern and southern groups is not a result of a recent translocation, and instead these populations represent independent evolutionarily significant units. We conclude that these newly discovered and phenotypically unique cichlid populations are already threatened by hybridization with an invasive species, and propose that these irreplaceable genetic resources would benefit from conservation interventions.
Why do few medical students report their experiences of mistreatment to administration?
Authors: Bell Amanda , Cavanagh Alice , Connelly Catherine E. , Walsh Allyn , Vanstone Meredith
Published: October 2020

Introduction

Over 50% of medical students worldwide report experiencing mistreatment and abuse during their clinical education, yet only a small proportion of students report these concerns to administration. It is unknown how medical students make sense of their experiences of mistreatment and come to decide whether to formally report these experiences. Improved understanding of this phenomenon will facilitate changes at the administrative and institutional levels to better support students.

Methods

Using Constructivist Grounded Theory, we interviewed 19 current and former medical students from one institution about their experiences with mistreatment and reporting. Data were analysed in an iterative fashion, using focused and theoretical forms of coding.

Results

The decision of whether to report mistreatment is only one phase in the process that students report experiencing when encountering mistreatment. This process can be understood as a journey consisting of five phases: Situating, Experiencing and Appraising, Reacting, Deciding and Moving Forward. Students move through these phases as they come to understand their position as medical learners and their ability to trust and be safe within this institution. Each experience of mistreatment causes students to react to what has happened to them, decide if they will share their experiences and reach out for support. They choose if they are going to report the mistreatment, at what cost and for what outcomes. Students continue through their training while incorporating their experiences into their understanding of the culture in which they are learning and continually resituating themselves within the institution.

Discussion

Student perceptions of trust or mistrust in their educational institution are highly influential when it comes to reporting mistreatment. Interventions designed to support students and decrease exposure to mistreatment may be best focused on increasing organisational trust between students and the medical school.
Treatment and mortality outcomes in patients with other extrapulmonary cryptococcal disease compared with central nervous system disease
Authors: Mejia‐Chew Carlos , Sung Abby , Larson Lindsey , Powderly William G. , Spec Andrej
Published: October 2020

Background

Determining the extent of cryptococcal disease (CD) is key to therapeutic management. Treatment with fluconazole is only recommended for localised pulmonary disease. Induction therapy with amphotericin B (AmB) and flucytosine is recommended for disease at other sites, irrespective of central nervous system (CNS) involvement, but this is not often followed in patients without meningitis. In this study, we compared treatment and mortality between patients with CD of the CNS and other extrapulmonary (OE) sites.

Methods

This is a retrospective, single‐centre study of all hospitalised patients with nonpulmonary cryptococcal infection from 2002 to 2015 who underwent lumbar puncture. Demographics, predisposing factors, comorbidities, clinical presentation, laboratory values, antifungal treatment and mortality data were collected to evaluate 90‐day mortality and treatment differences between patients with OE and CNS CD. Survival analysis was performed using multivariable Cox regression analysis.

Results

Of 193 patients analysed, 143 (74%) had CNS CD and 50 (26%) had OE CD. Ninety‐day mortality was 23% and similar between the OE and CNS CD groups (22% vs 23%, p = .9). In the comorbidity‐adjusted multivariable Cox regression model, mortality risk was similar in the OE and CNS groups. Fewer patients with OE CD received induction therapy with AmB and flucytosine compared to those with CNS disease (28% vs 71.3%, p < .001).

Conclusion

Patients with OE CD had similar 90‐day mortality compared to those with CNS disease. Despite current guideline recommendations, patients with OE disease were less likely to receive appropriate induction therapy with AmB and flucytosine compared to patients with CNS disease.
Optogenetics in plants
Authors: Christie John M. , Zurbriggen Matias D.
Published: October 2020

The last two decades have witnessed the emergence of optogenetics; a field that has given researchers the ability to use light to control biological processes at high spatiotemporal and quantitative resolutions, in a reversible manner with minimal side‐effects. Optogenetics has revolutionized the neurosciences, increased our understanding of cellular signalling and metabolic networks and resulted in variety of applications in biotechnology and biomedicine. However, implementing optogenetics in plants has been less straightforward, given their dependency on light for their life cycle. Here, we highlight some of the widely used technologies in microorganisms and animal systems derived from plant photoreceptor proteins and discuss strategies recently implemented to overcome the challenges for using optogenetics in plants.
Legality and the Legal Relation
Authors: Somek Alexander
Published: October 2020

According to Immanuel Kant, legality means the quality of an action being merely and simply in conformity with a law. The article defends the significance of this notion and explains how it indicates the existence of a legal relation. The legal relation, in turn, is the result of resolving an antinomy between the social and the substantive dimension of moral judgment.
The Dual‐Nature Thesis: Which Dualism?
Authors: Sieckmann Jan‐Reinard
Published: October 2020

According to Robert Alexy’s dual‐nature thesis, “law necessarily comprises both a real or factual dimension and an ideal or critical one.” I will suggest, first, that various dualisms need to be distinguished, in particular the empirical and the normative, the real and the ideal, the formal (procedural) and the substantive; second, that the dualism of the empirical and the normative and, within the latter, of the real and the ideal “ought,” is not specific to law but pertains to any normative system; and, third, that a dualism that distinguishes law from morality is a dualism of formal and substantive principles, which also serves to explain the authoritative character of law.
A victim of regulatory arbitrage? Automatic exchange of information and the use of golden visas and corporate shells
Authors: Ahrens Leo , Hakelberg Lukas , Rixen Thomas
Published: October 2020

The multilateral adoption of the automatic exchange of information (AEI) on bank accounts held by nonresidents was a breakthrough in the fight against cross‐border tax evasion, which led to a substantial reduction in the value of bank deposits and investment portfolios in traditional tax havens. However, there is suspicion that sophisticated tax evaders engage in regulatory arbitrage of AEI provisions. We examine whether two widely discussed secrecy schemes, namely golden visas and anonymous trusts and shell corporations, have been used to circumvent information reporting. Relying on a difference‐in‐difference design, we only find scattered evidence for use of the secrecy schemes. Overall, our results suggest that regulatory arbitrage is not yet widespread, but it seems to increase over time. We thus provide evidence for the current effectiveness of the AEI but also show that closing remaining loopholes is of utmost importance. We link our findings to debates about the (im)possibility of re‐embedding neoliberal globalization.
A mathematical approach to severe hyponatremia and hypernatremia in renal replacement therapies
Authors: Tinawi Mohammad , Bastani Bahar
Published: October 2020

Severe dysnatremias are perplexing problems in patients undergoing renal replacement therapy on a chronic or acute basis. The ability to manipulate sodium concentration in the dialysate or replacement solutions is limited. Compounding dialysate or replacement fluids to alter sodium concentration could result in errors. Rapid correction of hyponatremia or hypernatremia due to equilibrium with dialysate or replacement solutions could lead to osmotic demyelination syndrome or cerebral edema respectively. Continuous renal replacement therapy is the preferred dialysis modality in patients with severe dysnatremias. In this article, we present simple formulas to determine the rate of hypotonic or hypertonic solutions needed to mitigate rapid correction of dysnatremias. These formulas can be used readily by the clinician at bedside.
Leading synchronous virtual teaching sessions
Authors: Nunneley Chloë E. , Fishman Michael , Sundheim Kathryn M. , Korus Rachel E. , Rosen Robert H. , Streater Blair A. , O’Donnell Katherine A. , Newman Lori R. , Marcus Carolyn H.
Published: October 2020

While there has been increasing demand for online education over the past decade, social distancing recommendations during the COVID‐19 pandemic have accelerated the transition from the physical to the virtual classroom. Staples of clinical education, such as grand rounds, noon conferences, case conferences and chalk talks, have been abruptly forced to shift into the digital world. There is an immediate need for guidance on synchronous virtual teaching, especially since health professional educators may lack familiarity with the technologies available and theories that guide their use. The following framework can help educators plan, develop and deliver their virtual teaching sessions to optimize student engagement and produce meaningful learning outcomes.
A toolbox for conducting an online OSCE
Authors: Shehata Mohamed H. , Kumar Archana P. , Arekat Mona R. , Alsenbesy Mohamed , Mohammed Al Ansari Ahmed , Atwa Hani , Ahmed Samar A. , Deifalla Abdelhalim
Published: October 2020

This toolbox highlights the lessons learned and the tools used to run the online OSCE at the College of Medicine and Medical Sciences, Arabian Gulf University (CMMS‐AGU) using Zoom™️. The examiners considered the examination to be valid in assessing all clinical skills except for psychomotor skills and students found it to be highly acceptable. We describe three phases. Planning and preparation phase in which situation analysis, aligning stakeholders, mobilizing resources, creating a shared vision, and ownership of the exam project take place. For successful implementation of examinations, detailed plans are needed including manpower, timings, number of stations and detailed description of the steps of the examination process. We provide a set of guiding questions for proper decision making related to online clinical exams. Implementation Phase in which piloting is very useful to apply improvements to the original plan and to outline the needed capacity building of the participating staff. We give a detailed description of the guiding documents, means of communication and features of ZOOM that were used. Evaluation phase we provide a guide for evaluating the process and outcome, including a list of key performance indicators.
Study on Intelligent Control of Gas Turbines for Extending Service Life Based on Reinforcement Learning
Authors: Zhou Dengji , Jia Xingyun , Hao Jiarui , Wang Duocai , Huang Dawen , Wei Tingting
Published: October 2020

Frequent changes in operating conditions can result in the great loss of the service life of gas turbines that work at high speed, high pressure, and high temperature. To improve the control system of gas turbines is of great significance for extending the service life, boosting the dynamic performance, and reducing the maintenance cost. Due to good dynamic response characteristics, the present control methods are neither capable of tackling the nonlinearity of the system nor adaptive to the frequent variations of operating conditions. As a powerful learning paradigm, reinforcement learning (RL) can explore the operation environment and make decisions adaptively. A novel intelligent control framework for the gas turbine control system is constructed by coupling a RL agent with a dynamic simulation model and a damage estimation model. Compared with the proportion, integral, differential (PID) and fuzzy control, the proposed method achieves better performance in both extending life and depicting dynamic characteristics, and reduces the overall damage to as low as 0.01% in the loading process. Besides, the overshoot and the adjusting time of the novel approach are lower and shorter than those of PID and fuzzy control by more than 90% and about 14%, respectively, but it takes longer to accelerate. Finally, the effect of different types of RL agents and their hyperparameters are investigated. The results show that the deep deterministic policy gradient (DDPG) agent can achieve the best performance. Furthermore, in addition to extending the life and improving the dynamic performance, the controlling framework presented is recommended to construct an intelligent dynamic control system for achieving various purposes.
Effects of Clearance on the Performance of a Labyrinth Seal Under Wet-Gas Conditions
Authors: Zhang Min , Childs Dara W. , Tran Dung L. , Shresth Hari
Published: October 2020

The labyrinth seal is one of the most popular noncontact annular seals used in centrifugal compressors to improve machine efficiency by reducing the secondary flow leakage. Reducing the radial clearance Cr can effectively decrease the seal's leakage and therefore increase the machine efficiency. However, reducing Cr can also introduce undesired effects on the machine's vibration behaviors. This paper experimentally studies the impact of reducing Cr on the leakage and rotordynamic coefficients of a 16-tooth see-through labyrinth seal under wet-gas conditions. The test seal's inner diameter is 89.256 mm. Two rotors with different diameters are used to obtain two radial clearances (0.102 mm and 0.178 mm). Tests are carried out at a supply pressure of 62 bars, three speeds from 10 krpm to 20 krpm, three pressure ratios from 0.21 to 0.46, and six inlet liquid volume fractions (LVFs) from zero to 15%. The test fluid is a mixture comprised of air and silicon oil. Test results show that, for all pure-air and mainly air conditions, decreasing Cr decreases (as expected) the test seal's leakage mass flowrate. For all test cases, direct dynamic stiffness KΩ is negative, producing a negative centering force on the associated rotor. For inlet LVF ≤ 8%, the effects of decreasing Cr on KΩ are negligible. When inlet LVF = 12% and 15%, decreasing Cr increases KΩ (decreases the magnitude). In other words, when inlet LVF = 12% and 15%, decreasing Cr reduces the test seal's negative centering force on the rotor, and would increase the critical speeds of the rotor. The value of the effective damping Ceff near 0.5ω represents the seal's capability to suppress the rotor's potential whirling motion at about 0.5ω. For all pure-air and mainly air conditions, decreasing Cr generally increases the Ceff value near 0.5ω; i.e., decreasing Cr improves the test seal's stabilizing capability against the rotor's potential whirling motion at about 0.5ω.
XPS group array analysis of a combinatorial Ni-Ti-Co thin film library
Authors: Counsell Jonathan D. P. , Al Hasan Naila M. , Walton Edward , Gao Tieren , Hou Huilong , Takeuchi Ichiro
Published: October 2020

The last few decades have seen rapid development in computational and theoretical tools for simulating, fabricating, and characterizing material systems. In this report, the potential of surface characterization by x-ray photoelectron spectroscopy (XPS) to provide rapid elemental and chemical state information is presented. The development of the group analysis array functionality is significant for facilitating processing and display of large datasets in the application of XPS analysis to combinatorial materials discovery. We demonstrate that group array analysis provides a more detailed understanding of the chemical distribution across a Ni-Ti-Co combinatorial thin-film materials library.
Raman scattering, emission, and deep defect evolution in ZnO:In thin films
Authors: Torchynska Tetyana , El Filali Brahim , Jaramillo Gomez Juan Antonio , Polupan Georgiy , Ramírez García Jorge Luis , Shcherbyna Lyudmyla
Published: October 2020

The impact of In doping on the parameters of ZnO films has been studied. Film structure, emission, and evolution of O- and In-related defects versus In contents have been investigated using Raman scattering, photoluminescence (PL), x-ray diffraction, and high-resolution x-ray photoelectron spectroscopy (HR-XPS). Three stages of the variation of optical and structural parameters of ZnO films at In doping were detected. The formation of In-related point defects is connected with the first two stages, which is accompanied by improving the ZnO crystal structure, the insignificant changes of Raman scattering spectra, and the intensity increases of high energy emission bands. At the third stage of In doping, the intensities of Raman peaks and PL bands decrease owing to the formation of In-related nanoclusters and O-related defects. To analyze the In-related defects, HR-XPS was monitored for the lines (i) In 3d3/2 and In3d5/2, and (ii) In4d3/2 and In4d5/2 in In-doped ZnO thin films. The trend in the change of the In ion charges versus In contents has been revealed and discussed.
Critics slam NIH for demands on bat grant targeted by Trump
Authors: Wadman Meredith
Published: October 2020

Nobelists, former agency leaders deplore politicization.
How ‘elite controllers’ tame HIV without drugs
Authors: Cohen Jon
Published: October 2020

Rare people who naturally subdue the virus may weed out cells with active HIV genomes.
NASA mission set to sample carbon-rich asteroid
Authors: Voosen Paul
Published: October 2020

Bennu's thick carbonate veins suggest past life as a water world.
Technology Feature | Genomics comes full circle
Authors: Dove Alan
Published: October 2020

Microbiomics goes meta: Scientists are using the DNA of all the microbes in entire ecosystems to sequence and identify new bacteria, viruses, and fungi.
Black phosphorus composites with engineered interfaces for high-rate high-capacity lithium storage
Authors: Jin Hongchang , Xin Sen , Chuang Chenghao , Li Wangda , Wang Haiyun , Zhu Jian , Xie Huanyu , Zhang Taiming , Wan Yangyang , Qi Zhikai , Yan Wensheng , Lu Ying-Rui , Chan Ting-Shan , Wu Xiaojun , Goodenough John B. , Ji Hengxing , Duan Xiangfeng
Published: October 2020

Engineering phosphorous anodes

A focus of battery research has been the development of a range of lithium, sodium, and potassium cathodes, but improving anode materials is also an important goal. Silicon has shown some promise for replacing graphite because of its exceptional capacity, but the dramatic volume change during lithiation-delithiation processes often leads to failure. Jin
et al.
developed a composite that is made of black phosphorous and graphite in its core and covered with swollen polyaniline. In contrast to previous efforts, bonding between the carbon and phosphorous allows for a high charging rate without sacrifices in capacity and cycling stability.

Science
, this issue p.
192
Spacetime from bits
Authors: Van Raamsdonk Mark
Published: October 2020

Spacetime, reconstructed

Theories of holographic duality feature a correspondence between a gravitational system and a strongly interacting conformal field theory (CFT) living on the system's boundary. Through this correspondence, the CFT encodes the geometry of spacetime in the gravitational system. Van Raamsdonk analyzed the role of entanglement in this theoretical framework. Instead of considering a single CFT, the author's starting point was a collection of CFT “bits” that are mutually entangled but do not interact with one another. The spacetime that these bits collectively encode was then shown to be arbitrarily close to the one encoded by the original CFT, suggesting that entanglement plays a crucial role in the emergence of spacetime.

Science
, this issue p.
198
Computational social science: Obstacles and opportunities
Authors: Lazer David M. J. , Pentland Alex , Watts Duncan J. , Aral Sinan , Athey Susan , Contractor Noshir , Freelon Deen , Gonzalez-Bailon Sandra , King Gary , Margetts Helen , Nelson Alondra , Salganik Matthew J. , Strohmaier Markus , Vespignani Alessandro , Wagner Claudia
Published: October 2020

Data sharing, research ethics, and incentives must improve
The heterogeneity of persistent slip band nucleation and evolution in metals at the micrometer scale
Authors: Lavenstein Steven , Gu Yejun , Madisetti Dylan , El-Awady Jaafar A.
Published: October 2020

Disentangling fatigue

Metal fatigues when repeatedly loaded, ultimately failing when cracks form and propagate through the material. Lavenstein
et al.
studied the origins of this process in nickel. Using high-resolution observations, they tracked how dislocations evolved into microstructural features called persistent slip bands that preceded crack formation. The evolution of tangles of dislocations to a more regularly spaced pattern form the basis for the persistent slip bands and provide a road map for understanding fatigue cracking in metals.

Science
, this issue p.
eabb2690
Increased extinction in the emergence of novel ecological communities
Authors: Pandolfi John M. , Staples Timothy L. , Kiessling Wolfgang
Published: October 2020

Change begets change

In the Anthropocene, humans are altering ecosystems, causing extinctions, and reassorting species distributions. As we facilitate these changes, we are creating new collections of species. Such “novel communities” are not specific to our epoch, and the patterns of diversity and extinction associated with past events can shed light on the implications of current community restructuring. Pandolfi
et al.
looked at marine plankton communities over the past ∼66 million years and found that the emergence of novel communities leads to further novelty and extinction (see the Perspective by Dornelas and Madin). Although community change is a natural biological response to environmental change, the current rate of change could lead to impending and rapid impacts.

Science
, this issue p.
220
; see also p.
164
Alternating sequences of future and past behavior encoded within hippocampal theta oscillations
Authors: Wang Mengni , Foster David J. , Pfeiffer Brad E.
Published: October 2020

Representing the past and the future

Adaptive behavior requires the ability to analyze experience both prospectively and retrospectively. How can forward-ordered neural activity facilitate the storage or expression of reverse-ordered sequences? Wang
et al.
used multitetrode recordings from many individual hippocampal CA1 neurons in rats while simultaneously recording field potentials expressing theta oscillations. Spatial representation in the place cell network oscillated between forward and backward sweeps within each theta oscillation. Backward replay was associated with theta peaks, whereas forward replay was associated with theta troughs. Most cells fell into one category, but some corresponding to deep-layer neurons showed bimodular responses. Backward replay was driven by entorhinal inputs, whereas forward replay was evoked by CA3 inputs. These are important insights into the underlying basis of coding future and past experiences.

Science
, this issue p.
247
Zika virus infection enhances future risk of severe dengue disease
Authors: Katzelnick Leah C. , Narvaez César , Arguello Sonia , Lopez Mercado Brenda , Collado Damaris , Ampie Oscarlett , Elizondo Douglas , Miranda Tatiana , Bustos Carillo Fausto , Mercado Juan Carlos , Latta Krista , Schiller Amy , Segovia-Chumbez Bruno , Ojeda Sergio , Sanchez Nery , Plazaola Miguel , Coloma Josefina , Halloran M. Elizabeth , Premkumar Lakshmanane , Gordon Aubree , Narvaez Federico , de Silva Aravinda M. , Kuan Guillermina , Balmaseda Angel , Harris Eva
Published: October 2020

Double whammy

Dengue and Zika virus epidemics have been lapping each other around the globe. These are closely related mosquito-borne viruses with about 40% homology within the envelope protein. We know that subsequent dengue infections bring a risk of antibody-dependent disease enhancement. Whereas emphasis has been placed on how prior dengue immunity affects Zika infection, little is known about how prior Zika immunity may affect dengue disease. Katzelnick
et al.
have been following a well-characterized and established pediatric cohort in Nicaragua who were serially exposed to both flaviviruses in recent years (see the Perspective by Clapham). This study shows not only that a previous history of just one round of dengue is a problem but also that prior Zika immunity creates an increased risk for severe dengue virus sereotype 2 infection. By contrast, multiple infections raise antibodies to protective levels.

Science
, this issue p.
1123
; see also p.
1055
WUSCHEL triggers innate antiviral immunity in plant stem cells
Authors: Wu Haijun , Qu Xiaoya , Dong Zhicheng , Luo Linjie , Shao Chen , Forner Joachim , Lohmann Jan U. , Su Meng , Xu Mengchu , Liu Xiaobin , Zhu Lei , Zeng Jian , Liu Sumei , Tian Zhaoxia , Zhao Zhong
Published: October 2020

Building a safe space for stem cells

The meristem, the collection of stem cells that builds plants, is resistant to viral infection. Wu
et al.
now show that WUSCHEL, a transcription factor that helps to sustain stem cell production in the shoot apical meristem of
Arabidopsis
, also protects that stem cell domain from viruses. WUSCHEL inhibited viral protein synthesis by repressing methyltransferases that regulate ribosomal RNA processing and ribosome stability.

Science
, this issue p.
227
A history of insatiable intellectuals
The Polymath: A Cultural History from Leonardo da Vinci to Susan Sontag
Peter Burke
Yale University Press, 2020. 352 pp.
Authors: Robinson Andrew
Published: October 2020

Proficient in a range of topics, polymaths are overlooked as often as they are celebrated
Cryo-EM with sub–1 Å specimen movement
Authors: Naydenova Katerina , Jia Peipei , Russo Christopher J.
Published: October 2020

Going for the gold

Single-particle cryogenic electron microscopy (cryo-EM) has become a go-to technique for structural biologists. Although data-processing and reconstruction methods have improved, innovations in sample preparation and data collection are essential to reliably achieve high-resolution reconstructions while also reducing the amount of time required per structure. Naydenova
et al.
tackled the issue of electron beam–induced particle movement, a major source of information loss, by designing a gold sample support that prevents buckling of the extremely thin layer of ice in which the particles are suspended (see Perspective by Rapp and Carragher). The negligible particle displacement permits extrapolation to “zero exposure” structure factors, revealing features typically lost in cryo-EM structures. Far fewer particles per unit resolution are required, which greatly accelerates structure determination, especially at high resolution.

Science
, this issue p.
223
; see also p.
171
Using paleo-archives to safeguard biodiversity under climate change
Authors: Fordham Damien A. , Jackson Stephen T. , Brown Stuart C. , Huntley Brian , Brook Barry W. , Dahl-Jensen Dorthe , Gilbert M. Thomas P. , Otto-Bliesner Bette L. , Svensson Anders , Theodoridis Spyros , Wilmshurst Janet M. , Buettel Jessie C. , Canteri Elisabetta , McDowell Matthew , Orlando Ludovic , Pilowsky July A. , Rahbek Carsten , Nogues-Bravo David
Published: October 2020

Using the past to inform the future

The late Quaternary paleorecord, within the past ∼130,000 years, can help to inform present-day management of the Earth's ecosystems and biota under climate change. Fordham
et al.
review when and where rapid climate transitions can be found in the paleoclimate record. They show how such events in Earth's history can shape our understanding of the consequences of future global warming, including rates of biodiversity loss, changes in ecosystem structure and function, and degradation in the goods and services that these ecosystems provide to humanity. They also highlight how recent developments at the intersection of paleoecology, paleoclimatology, and macroecology can provide opportunities to anticipate and manage the responses of species and ecosystems to changing climates in the Anthropocene.

Science
, this issue p.
eabc5654