bluuebunny/crossref_metadata_2025 huggingface dataset:
Obstetric and Perinatal Outcomes in Pregnancies Conceived After Preimplantation Genetic Testing for Monogenetic Diseases
Authors: Feldman Baruch , Orvieto Raoul , Weisel Marine , Aizer Adva , Meyer Raanan , Haas Jigal , Kirshenbaum Michal
Published: September 2020

OBJECTIVE:

To investigate whether the addition of embryo biopsy performed during preimplantation genetic testing for monogenic diseases is associated with a higher risk of obstetric and neonatal complications compared with in vitro fertilization (IVF) without preimplantation genetic testing or spontaneously conceived pregnancies.

METHODS:

This is a cohort study of all pregnancies conceived after preimplantation genetic testing for monogenic diseases (PGT-M group) from 2006 to 2018 at Sheba Medical Center, Israel. The control groups included patients who had conceived spontaneously (spontaneous conception group) or by IVF without preimplantation genetic testing (IVF group) and delivered at Sheba Medical Center. The obstetrics outcomes were compared among the groups. Multivariable regression modeling was performed, focusing on the relationship between preimplantation genetic testing and adverse outcomes.

RESULTS:

Final analysis included 345 singleton and 76 twin deliveries in the PGT-M group. The spontaneous conception group included 5,290 singleton and 92 twin deliveries. The IVF group included 422 singleton and 101 twin deliveries. Among singleton pregnancies, patients in the PGT-M group had a higher rate of hypertensive disorders (6.9%) compared with those in the spontaneous conception group (2.3%; odds ratio [OR] 3.3; 95% CI 1.9–4.8; adjusted odds ratio [aOR] 14.8; 95% CI 7.4–29.8) and the IVF group (4.7%; OR 1.5; 95% CI 0.8–2.7; aOR 5.9; 95% CI 1.9–18.2). Likewise, patients in the PGT-M group had a higher rate of small-for-gestational age neonates (12.4%) compared with those in the spontaneous conception group (3.9%; OR 3.4; 95% CI 2.4–4.9; aOR 2.3; 95% CI 1.5–3.4) and the IVF group (4.5%; OR 3; 95% CI 1.7–5.2; aOR 2.5; 95% CI 1.7–5.2). Among twin pregnancies, patients in the PGT-M group also had an increased rate of hypertensive disorders compared with those in the spontaneous conception group (4.3%; OR 4.1; 95% CI 1.2–13.3; aOR 10.9; 95% CI 2.3–50) and the IVF group (4%; OR 4.5; 95% CI 1.4–14.7; aOR 3.7; 95% CI 1.1–12.8).

CONCLUSION:

Pregnancies conceived after preimplantation genetic testing for monogenic disorders were associated with an increased risk of obstetric complications compared with pregnancies conceived spontaneously or by IVF without preimplantation genetic testing.
24/7 Primary Percutaneous Coronary Intervention as a National Program
Authors: Abdi Seifollah , Haji Aghajani Mohammad , Janbabaei Ghasem , Noohi Feridoun , Kermanchi Jamshid , Salarifar Mojtaba , Geraiely Babak , Sadeghipour Parham , Kazemi-Saleh Davoud , Firouzi Ata , Soleimani Abbas , Mortazavi Seyedeh Hamideh
Published: September 2020

Due to the importance of early treatment in the final prognosis of ST-elevation myocardial infarction (STEMI) patients, full-time provision of revascularization services should be available 24 hours a day, 7 days a week (24/7) in conjunction with a fully-coordinated pre-hospital emergency system and equipped centers with experienced medical teams. We reviewed the 24/7 primary percutaneous coronary intervention (PCI) management registry and evaluated the quality of care and patient management as well as the temporal trend of provided health care services. In the present cross-sectional study, we retrieved the data on 11,563 STEMI patients having undergone primary PCI at the thirty-one 24/7 PCI-capable hospitals through the national 24/7 STEMI management program between September 2015 and August 2017 in Iran. The median (25th–75th) age of the patients was 59 (51–68) years. The median (25th–75th) time of door-to-device was 64 (41–100) min and 68% of patients achieved door to device time of ≤90 min. There was no significant difference in the median door-to-device time between the general and heart hospitals. This is the first Iranian National attempt to provide a uniform guideline-driven standard management in patients with STEMI undergoing primary PCI in a 24/7 program. We demonstrated an acceptable door-to-device time consistent with the recommendations of the current guidelines. We observed higher door-to-device time in older patients, female patients, and those where the culprit lesion was other than the left anterior descending coronary artery. Efforts should be made to improve door-to-device time in all patients or groups.
The associations between nutritional and functional status during recovery from Guillain–Barré syndrome: a retrospective study
Authors: Polončič Petra , Novak Primož , Puzić Ravnjak Nataša , Majdič Neža
Published: September 2020

Patients with Guillain–Barré syndrome (GBS) are at high risk for inadequate nutrition throughout their illness, yet the wider impact of malnutrition in this population remains unknown. Thus, the purpose of our study was to investigate the associations between nutritional status and functional status at admission to inpatient rehabilitation for GBS and to determine whether the admission phase angle, a biological marker of cellular health, is a prognostic indicator of functional improvement at the end of rehabilitation. The study included 27 participants recovering from GBS who screened positive for nutritional risk upon admission to rehabilitation. According to the Global Leadership Initiative on Malnutrition criteria, the majority of participants were classified as malnourished. A decreased phase angle was found in 93% (mean 3.7°, SD 1.3°). Lower phase angle was moderately associated with lower motor Functional Independence Measure (mFIM) at admission (r = 0.53, P = 0.005), suggesting that phase angle may be an indicator of functional status. By the end of rehabilitation, all participants improved functional independence and muscle strength, and the majority improved walking abilities. However, the correlation between admission phase angle and mFIM efficiency was not statistically significant (P = 0.3867). We conclude that malnutrition is significantly associated with low functional independence and muscle strength at admission. The inability of admission phase angle to predict functional improvement is probably due to the complex interactions between recovery from GBS and interventions provided during a comprehensive multidisciplinary rehabilitation for GBS, and also relatively small sample size.
Analysis of partial sequences of the RNA-dependent RNA polymerase gene as a tool for genus and subgenus classification of coronaviruses
Authors: Wilkinson David A. , Joffrin Léa , Lebarbenchon Camille , Mavingui Patrick
Published: September 2020

The recent reclassification of the Riboviria, and the introduction of multiple new taxonomic categories including both subfamilies and subgenera for coronaviruses (family Coronaviridae, subfamily Orthocoronavirinae), represents a major shift in how official classifications are used to designate specific viral lineages. While the newly defined subgenera provide much-needed standardization for commonly cited viruses of public health importance, no method has been proposed for the assignment of subgenus based on partial sequence data, or for sequences that are divergent from the designated holotype reference genomes. Here, we describe the genetic variation of a 387 nt region of the coronavirus RNA-dependent RNA polymerase (RdRp), which is one of the most used partial sequence loci for both detection and classification of coronaviruses in molecular epidemiology. We infer Bayesian phylogenies from more than 7000 publicly available coronavirus sequences and examine clade groupings relative to all subgenus holotype sequences. Our phylogenetic analyses are largely coherent with whole-genome analyses based on designated holotype members for each subgenus. Distance measures between sequences form discrete clusters between taxa, offering logical threshold boundaries that can attribute subgenus or indicate sequences that are likely to belong to unclassified subgenera both accurately and robustly. We thus propose that partial RdRp sequence data of coronaviruses are sufficient for the attribution of subgenus-level taxonomic classifications and we supply the R package, MyCoV, which provides a method for attributing subgenus and assessing the reliability of the attribution.
Trend prediction of COVID-19 based on ARIMA model in mainland of China
Authors: Han Chuqiao , Ju Xifeng , Zheng Jianghua
Published: September 2020

The ongoing pandemic of COVID-19 has aroused widespread concern around the world and poses a severe threat to public health worldwide. In this paper, the autoregressive integrated moving average (ARIMA) model was used to predict the epidemic trend of COVID-19 in mainland of China. We collected the cumulative cases, cumulative deaths, and cumulative recovery in mainland of China from January 20 to June 30, 2020, and divided the data into experimental group and test group. The ARIMA model was fitted with the experimental group data, and the optimal model was selected for prediction analysis. The predicted data were compared with the test group. The average relative errors of actual cumulative cases, deaths, recovery and predicted values in each province are between −22.32%−22.66%, −9.52%−0.08%, −8.84%−1.16, the results of the comprehensive experimental group and test group show The error of fitting and prediction is small, the degree of fitting is good, the model supports and is suitable for the prediction of the epidemic situation, which has practical guiding significance for the prevention and control of the epidemic situation.

Highlights:

We predicted future COVID-19 occurrences in mainland of China based on ARIMA model.

We validated the model based on the previous outbreak data with actual data for June, 2020.

The measures taken by the government have contained spread of the epidemic

The combination of multiple models may improve the robustness of the model
Effectiveness of digital interventions to improve household and community infection prevention and control behaviours and to reduce incidence of respiratory and/or gastro-intestinal infections: A rapid systematic review
Authors: Gold Natalie , Hu Xiao-Yang , Denford Sarah , Xia Ru-Yu , Towler Lauren , Groot Julia , Gledhill Rachel , Willcox Merlin , Ainsworth Ben , Miller Sascha , Denison-Day James , Moore Michael , Rice Cathy , Bostock Jennifer , Stuart Beth , Morton Kate , Little Paul , Amlôt Richard , Chadborn Tim , Yardley Lucy
Published: September 2020

Background

Digital interventions have potential to efficiently support improved hygiene practices to reduce transmission of COVID-19.

Objective

To evaluate the evidence for digital interventions to improve hygiene practices within the community.

Methods

We reviewed articles published between 01 January 2000 and 26 May 2019 that presented a controlled trial of a digital intervention to improve hygiene behaviours in the community. We searched MEDLINE, Embase, PsycINFO, Cochrane Controlled Register of Trials (CENTRAL), China National Knowledge Infrastructure and grey literature. Trials in hospitals were excluded, as were trials aiming at prevention of sexually transmitted infections; only target diseases with transmission mechanisms similar to COVID-19 (e.g. respiratory and gastrointestinal infections) were included. Trials had to evaluate a uniquely digital component of an intervention. Study designs were limited to randomised controlled trials, controlled before-and-after trials, and interrupted time series analyses. Outcomes could be either incidence of infections or change in hygiene behaviours. The Risk of Bias 2 tool was used to assess study quality.

Results

We found seven studies that met the inclusion criteria. Six studies reported successfully improving self-reported hygiene behaviour or health outcomes, but only one of these six trials confirmed improvements using objective measures (reduced consultations and antibiotic prescriptions), Germ Defence. Settings included kindergartens, workplaces, and service station restrooms. Modes of delivery were diverse: WeChat, website, text messages, audio messages to mobiles, electronic billboards, and electronic personal care records. Four interventions targeted parents of young children with educational materials. Two targeted the general population; these also used behaviour change techniques or theory to inform the intervention. Only one trial had low risk of bias, Germ Defence; the most common concerns were lack of information about the randomisation, possible bias in reporting of behavioural outcomes, and lack of an analysis plan and possible selective reporting of results.

Conclusion

There was only one intervention that was judged to be at low risk of bias, Germ Defence, which reduced incidence and severity of illness, as confirmed by objective measures. Further evaluation is required to determine the effectiveness of the other interventions reviewed.
Inference of SARS-CoV-2 spike-binding neutralizing antibody titers in sera from hospitalized COVID-19 patients by using commercial enzyme and chemiluminescent immunoassays
Authors: Valdivia Arantxa , Torres Ignacio , Latorre Víctor , Francés-Gómez Clara , Albert Eliseo , Gozalbo-Rovira Roberto , Jesús Alcaraz María , Buesa Javier , Rodríguez-Díaz Jesús , Geller Ron , Navarro David
Published: September 2020

Background

Whether antibody levels measured by commercially-available enzyme or chemiluminescent immunoassays targeting the SARS-CoV-2 spike (S) protein can act as a proxy for serum neutralizing activity remains to be established for many of these assays.

Objectives

To evaluate the degree of correlation between neutralizing antibodies (NtAb) binding the SARS-CoV-2 Spike (S) protein and SARS-CoV-2-S-IgG levels measured by four commercial immunoassays in sera drawn from hospitalized COVID-19 patients.

Patients and Methods

Ninety sera from 51 hospitalized COVID-19 patients were assayed by a pseudotyped virus neutralization assay, the LIAISON SARS-CoV-2 S1/S2 IgG, the Euroimmun SARS-CoV-2 IgG ELISA, the MAGLUMI 2019-nCoV IgG and the COVID-19 ELISA IgG assays.

Results

Overall, the results obtained with the COVID-19 ELISA IgG test showed the highest agreement with the NtAb assay (κ, 0.85; 95% CI, 0.63-1). The most sensitive tests were the pseudotyped virus NtAb assay and the COVID-19 ELISA IgG assay (92.2% for both). Overall, the degree correlation between antibody titers resulting in 50% virus neutralization (NtAb50) in the pseudotyped virus assay and SARS-CoV-2 IgG levels was strong for the Euroimmun SARS-CoV-2 IgG ELISA (Rho = 0.73) and moderate for the remaining assays (Rho = 0.48 to 0.59). The kinetic profile of serum NtAb50titers could not be reliably predicted by any of the SARS-CoV-2 IgG immunoassays.

Conclusions

The suitability of SARS-CoV-2-S-IgG commercial immunoassays for inferring neutralizing activity of sera from hospitalized COVID-19 patients varies widely across tests and is influenced by the time of sera collection after the onset of symptoms.
A Continuously Active Antimicrobial Coating Remains Effective After Multiple Contamination Events
Authors: Ikner Luisa A. , Beck Valerie , Gundy Patricia M. , Gerba Charles P.
Published: September 2020

Liquid-based disinfection of environmental surfaces is a momentary intervention while the recontamination of these surfaces is continuous. In between disinfection cycles, contaminated surfaces remain a potential source of infection. The use of continuously active antimicrobial surface coatings would reduce the risk of transmission between routine cleaning and liquid disinfection events by serving as an “always-on” approach to reduce pathogen burden. We have recently reported on a surface coating having antiviral properties. Here, the spectrum of activity was broadened assessment efficacy of the coating to withstand multiple contamination events against viruses and pathogenic bacteria.
Mitigation Strategies and Compliance in the Covid-19 Fight; How Much Compliance is Enough?
Authors: Mukerjee Swati , Chow Clifton , Li Mingfei
Published: September 2020

Today, with only 4% of the world’s population, the U.S. is bearing a disproportionate share of COVID-19 infections. Seeking to understand this puzzle, we investigate how mitigation strategies and compliance can work together (or in opposition) to reduce (or increase) the spread of COVID-19 infection. Drilling down to the state level, we create specific state indices suitable for the U.S. to measure the degree of strictness of public mitigation measures. In this, we build on the Oxford Stringency Index. A modified time-varying SEIRD model, incorporating this Stringency Index as well as a Compliance Indicator to reduce the transmission, is then estimated with daily data for a sample of 6 U.S. states. These are New York, New Hampshire, New Mexico, Colorado, Texas, and Arizona. We provide a simple visual policy tool to evaluate the various combinations of mitigation policies and compliance that can reduce the basic reproduction number to less than one; this is the acknowledged threshold in the epidemiological literature to control the pandemic. States successful in combating the pandemic were able to achieve a suitable combination. Understanding of this relationship by the public and policy makers is key to controlling the pandemic. This tool has the potential to be used in a real-time, dynamic fashion for flexible policy options.
Kinetics of Immunoglobulins in Septic Shock Patients Treated with an IgM and IgA-Enriched Intravenous Preparation: an Observational Study
Authors: Berlot Giorgio , Scamperle Alice , Istrati Tatiana , Dattola Roberto , Longo Irene , Chillemi Antonino , Baronio Silvia , Quarantotto Giada , Roman-Pognuz Erik , Tomasini Ariella , Bixio Mattia
Published: September 2020

Objective

to assess the variations of the blood levels of immunoglobulins (Ig) in septic shock patients treated with an Ig preparation enriched in IgM and IgA (eIg).

Design

The blood levels of Ig in survivors (S) and non-survivors (NS) of a group of septic shock patients were measured before the initial administration (D0) and one (D1), four (D4) and seven (D7) days thereafter. The SAPS II score, the capillary permeability, the primary site of infection, the antibiotic appropriateness, the microorganisms isolated and the outcome at 28 days were also assessed.

Results

In the interval D0-D7 the IgM increased significantly only in the S while remained stable in NS; the IgA significantly increased in both groups; the IgG did not vary significantly in both groups. At D7 the capillary permeability significantly decreased in S but not in NS.

Conclusions

The kinetics of the different classes of Ig after eIg were different between S and NS. This could be related either to (a) different capillary permeability in the two groups and/or (b) higher Ig consumption in NS. Further studies to confirm the benefits of eIg in the treatment of sepsis syndrome, to define the specific target population and the correct eIg dose are warranted.
Transmitted HIV-1 is more pathogenic in heterosexual individuals than homosexual men
Authors: James Ananthu , Dixit Narendra M.
Published: September 2020

Transmission bottlenecks introduce selection pressures on HIV-1 that vary substantially with the mode of transmission. Recent studies on small cohorts have suggested that stronger selection pressures lead to fitter transmitted/founder (T/F) strains. Manifestations of this selection bias at the population level have remained elusive. Here, we analysed early CD4 cell count measurements reported from ∼340,000 infected heterosexual individuals (HSX) and men-who-have-sex-with-men (MSM), across geographies, ethnicities and calendar years and found them to be consistently lower in HSX than MSM (P<0.05). The corresponding average reduction in CD4 counts relative to healthy adults was 86.5% in HSX and 67.8% in MSM (P<10−4). This difference could not be attributed to differences in age, HIV-1 subtype, viral load, gender, ethnicity, time of transmission, or diagnosis delay across the groups. We concluded that the different selection pressures arising from the different predominant transmission modes have resulted in more pathogenic T/F strains in HSX than MSM.
Functional differences in the hypothalamic-pituitary-gonadal axis are associated with alternative reproductive tactics based on an inversion polymorphism
Authors: Loveland JL , Giraldo-Deck LM , Lank D , Goymann W , Gahr M , Küpper C
Published: September 2020

The evolution of social behavior depends on genetic changes, yet, how genomic variation manifests itself in behavioral diversity is still largely unresolved. Chromosomal inversions can play a pivotal role in producing distinct behavioral phenotypes, in particular, when inversion genes are functionally associated with hormone synthesis and signaling. Male Ruffs exhibit alternative reproductive tactics (ARTs) with an autosomal inversion determining two alternative morphs with clear behavioral and hormonal differences to the ancestral morph. We investigated hormonal and transcriptomic differences in the pituitary and gonads. Using a GnRH challenge, we found that the ability to synthesize testosterone in inversion carriers is severely constrained, whereas the synthesis of androstenedione, a testosterone precursor, is not. Inversion morphs were able to produce a transient increase in androstenedione following the GnRH injection, supporting the view that pituitary sensitivity to GnRH is comparable to that of the ancestral morph. We then performed gene expression analyses in a second set of untreated birds and found no evidence of alterations to pituitary sensitivity, gonadotropin production or gonad sensitivity to luteinizing hormone or follicle-stimulating hormone across morphs. Inversion morphs also showed reduced progesterone receptor expression in the pituitary. Strikingly, in the gonads, inversion morphs over-expressedSTAR, a gene that is located outside of the inversion and responsible for providing the cholesterol substrate required for the synthesis of sex hormones. In conclusion, our results suggest that the gonads determine morph-specific differences in hormonal regulation.
Daily and Intermittent Smoking Decrease Gray Matter Volume and Concentrations of Glutamate, Creatine, Myo-Inositol andN-acetylaspartate in the Prefrontal Cortex
Authors: Faulkner Paul , Paioni Susanna Lucini , Kozhuharova Petya , Orlov Natasza , Lythgoe David J. , Daniju Yusuf , Morgenroth Elenor , Barker Holly , Allen Paul
Published: September 2020

Cigarette smoking is still the largest contributor to disease and death worldwide. Successful cessation is hindered by decreases in prefrontal glutamate concentrations and gray matter volume due to daily smoking. Because non-daily, intermittent smoking also contributes greatly to disease and death, understanding whether infrequent tobacco use is associated with reductions in prefrontal glutamate concentrations and gray matter volume may aid public health. Eighty-five young participants (41 non-smokers, 24 intermittent smokers, 20 daily smokers, mean age ~23 years old), underwent1H-magnetic resonance spectroscopy of the medial prefrontal cortex, as well as structural MRI to determine whole-brain gray matter volume. Compared to non-smokers, both daily and intermittent smokers exhibited lower concentrations of glutamate, creatine,N-acetylaspartate and myo-inositol in the medial prefrontal cortex, and lower gray matter volume in the right inferior frontal gyrus; these measures of prefrontal metabolites and structure did not differ between daily and intermittent smokers. Finally, medial prefrontal metabolite concentrations and right inferior frontal gray matter volume were positively correlated, but these relationships were not influenced by smoking status. This study provides the first evidence that both daily and intermittent smoking are associated with low concentrations of glutamate, creatine,N-acetylaspartate and myo-inositol, and low gray matter volume in the prefrontal cortex. Future tobacco cessation efforts should not ignore potential deleterious effects of intermittent smoking by considering only daily smokers. Finally, because low glutamate concentrations hinder cessation, treatments that can normalize tonic levels of prefrontal glutamate, such as N-acetylcysteine, may help intermittent and daily smokers to quit.
Enhanced endogenous activity predicts elimination of adult-born neurons in the mouse olfactory bulb
Authors: Su Xin , Kovalchuk Yury , Mojtahedi Nima , Garaschuk Olga
Published: September 2020

Adult-born cells, arriving daily into the rodent olfactory bulb, either integrate into the neural circuitry or get eliminated. Whether these two populations differ in their morphological or functional properties remains, however, unclear. Using longitudinalin vivotwo-photon imaging, we monitored dendritic morphogenesis, odor-evoked responsiveness, endogenous Ca2+signaling, and survival/death of adult-born juxtaglomerular neurons (abJGNs). We found that maturation of abJGNs is accompanied by a significant reduction in dendritic complexity, with surviving and subsequently eliminated cells showing similar degrees of dendritic remodeling. Surprisingly, 63% of eliminated abJGNs acquired odor-responsiveness before death, with amplitudes and time courses of odor-evoked responses similar to those recorded in surviving cells. We observed, however, a significant long-lasting enhancement of endogenous Ca2+signaling in subsequently eliminated abJGNs, visible already 6 days before death. These findings identify ongoing endogenous Ca2+signaling as a key predictor of abJGNs’ fate.
Executive coaching explained: the beginnings of a contingency approach
Authors: Offstein Evan H. , Dufresne Ronald L. , Childers Jr John S.
Published: September 2020

Purpose

In this paper, we problematize the prevailing assumptions in the executive coaching literature that effective coaching is deliberative, trust-based and relational in nature, thereby requiring significant time investment before the focal leader might realize enacted benefits from the coaching. Contrary to these prevailing assumptions, we propose five contingencies wherein a more direct, performance-first approach to coaching may be more effective.

Design/methodology/approach

This conceptual paper reviews relevant literature to develop testable propositions regarding directive coaching contingencies.

Findings

We develop propositions that argue executive coaches will need to employ a more directive, urgent and accountable coaching relationship when the executive's career is in jeopardy, the organization is in distress, if the leader needs to signal legitimacy, if the coaching occurs within the boundaries of a high reliability organization or if the coach is working with an executive who has interim status.

Originality/value

This paper intends to advance the theory and practice of executive coaching by challenging executive coaching orthodoxy regarding the need for a deliberative, relational approach to coaching. Future research should broaden this theorizing and empirically test our propositions.
Performance Investigation of Solar Organic Rankine Cycle Systems With and Without Regeneration and With Zeotropic Working Fluid Mixtures for Use in Micro-Cogeneration
Authors: Yaïci Wahiba , Entchev Evgueniy , Talebizadeh Sardari Pouyan
Published: September 2020

Globally there are several viable sources of renewable, low-temperature heat (below 130°C) particularly solar energy, geothermal energy, and energy generated from industrial wastes. Increased exploitation of these low-temperature options has the definite potential of reducing fossil fuel consumption with its attendant very harmful greenhouse gas emissions. Researchers have universally identified the organic Rankine cycle (ORC) as a practicable and promising system to generate electrical power from renewable sources based on its beneficial use of volatile organic fluids as working fluids (WFs). In recent times, researchers have also shown a preference for/an inclination towards deployment of zeotropic mixtures as ORC WFs because of their capacity to improve thermodynamic performance of ORC systems, a feat enabled by better matches of the temperature profiles of the WF and the heat source/sink.

This paper demonstrates both the technical feasibility and the notable advantages of using zeotropic mixtures as WFs through a simulation study of an ORC system. The study examines the thermodynamic performance of ORC systems using zeotropic WF mixtures to generate electricity driven by low-temperature solar heat source for building applications. A thermodynamic model is developed with an ORC system both with and excluding a regenerator. Five zeotropic mixtures with varying compositions of R245fa/propane, R245fa/hexane, R245fa/heptane, pentane/hexane and isopentane/hexane are evaluated and compared to identify the best combinations of WF mixtures that can yield high efficiency in their system cycles.

The study also investigates the effects of the volumetric flow ratio, and evaporation and condensation temperature glides on the ORC’s thermodynamic performance. Following a detailed analysis of each mixture, R245fa/propane is selected for parametric study to examine the effects of operating parameters on the system’s efficiency and sustainability index.

For zeotropic mixtures, results showed that there is an optimal composition range within which binary mixtures are inclined to perform more efficiently than the component pure fluids. In addition, a significant increase in cycle efficiency can be achieved with a regenerative ORC, with cycle efficiency ranging between 3.1–9.8% and 8.6–17.4% for ORC both without and with regeneration, respectively. Results also showed that exploiting zeotropic mixtures could enlarge the limitation experienced in selecting WFs for low-temperature solar organic Rankine cycles.
Fault Detection and Classification in Smart Grids Using Wavelet Analysis
Authors: Munir Muhammad Ibrahim , Hussain Sajid , Al-Alili Ali , Al Ameri Reem , El-Sadaany Ehab
Published: September 2020

One of the core features of the smart grid deemed essential for smooth grid operation is the detection and diagnosis of system failures. For a utility transmission grid system, these failures could manifest in the form of short circuit faults and open circuit faults. Due to the advent of the digital age, the traditional grid has also undergone a massive transition to digital equipment and modern sensors which are capable of generating large volumes of data. The challenge is to preprocess this data such that it can be utilized for the detection of transients and grid failures. This paper presents the incorporation of artificial intelligence techniques such as Support Vector Machine (SVM) and K-Nearest Neighbors (KNN) to detect and comprehensively classify the most common fault transients within a reasonable range of accuracy. For gauging the effectiveness of the proposed scheme, a thorough evaluation study is conducted on a modified IEEE-39 bus system. Bus voltage and line current measurements are taken for a range of fault scenarios which result in high-frequency transient signals. These signals are analyzed using continuous wavelet transform (CWT). The measured signals are afterward preprocessed using Discrete Wavelet Transform (DWT) employing Daubechies four (Db4) mother wavelet in order to decompose the high-frequency components of the faulty signals. DWT results in a range of high and low-frequency detail and approximate coefficients, from which a range of statistical features are extracted and used as inputs for training and testing the classification algorithms. The results demonstrate that the trained models can be successfully employed to detect and classify faults on the transmission system with acceptable accuracy.
Performance Analysis of a Solar Powered Organic Rankine Cycle With Energy Storage in Different U.S. Climate Zones
Authors: Hemmati Hadis , Zhang Jian , Spayde Emily , Mago Pedro J. , Cho Heejin
Published: September 2020

Solar-powered organic Rankine cycle (ORC) is a promising technology and has the potential to provide clean electric energy. Extensive studies on the design of ORC systems have been conducted and reported in the literature. However, very few studies have presented the influence of the climate zones on the performance of a solar-powered ORC, especially for an integrated ORC and energy storage system. This paper presents an analysis to determine the performance of a solar-powered ORC with electric energy storage (EES) to supply electricity to a building in different climate zones in the United States. The building type evaluated in this paper is a large office, and the energy consumption of the facility in each climate location was determined using EnergyPlus. The ORC-EES operational strategy used in this investigation consists of the ORC charging the EES when solar irradiation is sufficient to generate power. Then the EES provides power to the building when there is no solar energy available. The ORC-EES is evaluated based on the potential to reduce the operational cost, the primary energy consumption, and the carbon dioxide emission. Furthermore, the effect of the number of solar collectors and the EES size on the performance of the ORC-EES system is also studied.
Update on NREL Outdoor Exposure Campaign of Solar Mirrors
Authors: Celvi Daniel , Schreiber Christa , Tirawat Robert , Zhu Guangdong
Published: September 2020

Beginning in 2018, the National Renewable Energy Laboratory restarted exposure campaigns on new and archived samples as part of a multiyear project, some with outdoor exposure for more than a decade. By resuming exposure and collecting and analyzing data on thousands of samples going back decades, several goals can be advanced that can be difficult to determine within the timeline of most projects: 1) correlating an accelerated exposure campaign to outdoor aging, specifically with xenon arc lamp exposure chambers; 2) drawing conclusions between specific corrosion mechanisms and weather patterns; and 3) finding novel relationships between mirror composition and performance.

In addition to building and mining a database, we will experiment with new characterization techniques, primarily focused on macroscopic and microscopic imaging. In introducing these techniques more broadly, it may be possible to reveal a more direct line between optical performance and exposure campaigns by better understanding the degradation mechanisms occurring.
Numerical Simulation of Electrical Performance and Distribution of SOFC Stacks With Different Manifold Arrangement
Authors: Hou Quan , Wu Yuhua , Liu Haokun , Xu Xinhai , Xu Ben
Published: September 2020

In this study, a three-dimensional solid oxide fuel cell stack numerical model was developed and validated by experimental data. Five-cell SOFC stacks with different inlet and outlet manifold arrangement were investigated employing the numerical model. The stack polarization curve, current density, temperature, and flow distributions were analyzed. The results show that the effect of different manifold arrangement is almost neglected on the polarization curves and flow distribution. However, the current density and temperature distribution in individual unit of the stack can be influenced by the locations of inlets and outlets in the manifolds. Considering current density and temperature distribution uniformity as well as ease manufacturing and installation, the manifold arrangement with inlets at the top and outlets at the bottom for both fuel and air is recommended for SOFC stacks.
Selective Infrared Energy Harvesting by Nanoparticle Dispersions in Solar Thermal Desalination Systems
Authors: Hammonds James S. , Stancil Kimani A. , Adewuyi Olalekan S.
Published: September 2020

A significant portion of the infrared solar spectrum is either unused, or wasted by inefficient solar energy conversion. In this paper, we show that infrared light harvesting can also be accomplished by dispersions of polar nanoparticles. Polar nanoparticle dispersions in a selective absorber may result in Solar Thermal Desalination (STD) systems that aim to maximize the solar-to-heat conversion efficiency by managing the thermal radiative and conduction losses. In noting that irregular dispersions of polar nanoparticles are less costly than regularly spaced nanostructures to manufacture at large scales, we describe the solar absorptivity as a function of a nanoparticle chain model determined emissivity and thermal conductance. The near-field interactions between nanoparticles are explained by modeling the nanoparticles as dispersed electromagnetic dipole oscillations that interact with solar light. An FDTD model of polar nanodispersions near an optical cavity is used to demonstrate infrared harvesting. With this model, we show that the infrared light-harvesting mechanisms of silica nanoparticles involve local and propagating surface phonon polaritons and varying the volume fraction changes radiation transport properties by several orders of magnitude. In discussing STD systems, we demonstrate a potential to use nanoparticle chains to create novel selective absorbers with tunable solar absorptivity.
Testing and Simulations of Spatial and Temporal Temperature Variations in a Particle-Based Thermal Energy Storage Bin
Authors: Sment Jeremy N. , Martinez Mario J. , Albrecht Kevin , Ho Clifford K.
Published: September 2020

The National Solar Thermal Test Facility (NSTTF) at Sandia National Laboratories is conducting research on a Generation 3 Particle Pilot Plant (G3P3) that uses falling sandlike particles as the heat transfer medium. The system will include a thermal energy storage (TES) bin with a capacity of 6 MWht¬ requiring ∼120,000 kg of flowing particles. Testing and modeling were conducted to develop a validated modeling tool to understand temporal and spatial temperature distributions within the storage bin as it charges and discharges.

Flow and energy transport in funnel-flow was modeled using volume averaged conservation equations coupled with level set interface tracking equations that prescribe the dynamic geometry of particle flow within the storage bin. A thin layer of particles on top of the particle bed was allowed to flow toward the center and into the flow channel above the outlet.

Model results were validated using particle discharge temperatures taken from thermocouples mounted throughout a small steel bin. The model was then used to predict heat loss during charging, storing, and discharging operational modes at the G3P3 scale. Comparative results from the modeling and testing of the small bin indicate that the model captures many of the salient features of the transient particle outlet temperature over time.
Gen3 CSP Materials: Critical Review of Limited Existing and New Survey Data
Authors: Gunawan Andrey , Arkhurst Bettina K. , Brankovic Sonja A. , Yee Shannon K.
Published: September 2020

Novel high temperature (≥ 700°C) Heat Transfer Medias (HTMs, e.g., molten salts) and corrosion-resistant Containment Materials (CMs, e.g., metal alloys or ceramics) are necessary for concentrated solar power (CSP) given the emphasis on higher temperatures and high cycle efficiency in the 3rd generation CSP (Gen3 CSP) technologies. In early 2019, we sent out an online survey to the Gen3 CSP community to fully assess the communal needs for thermophysical properties measurements of which HTMs and CMs, and what temperature range and other testing environments would be ideal for those materials. Based on the recorded responses, seven unique HTMs and twenty-six unique CMs were identified. Since then the list has been constantly updated, following our interactions and inputs from the Gen3 CSP community, with some new materials substituting their older counterparts. Currently, there are total of ten unique HTMs and twenty-nine unique CMs that are under consideration by the Gen3 CSP community. By analyzing the available body of research to date and combining it with our survey data from within the Gen3 CSP community, this paper presents trends of what people in the CSP world are thinking regarding materials worth investigating and suggests which thermophysical property measurements are critical to advance high-temperature CSP systems.
Effect of Synthesis Protocol in Enhancing Heat Capacity of Molten Salt Nanofluids
Authors: El Far Baha , Rizvi Syed Muhammad Mujtaba , Nayfeh Yousof , Shin Donghyun
Published: September 2020

Concentrated solar power (CSP) incorporated with thermal energy storage (TES) is an appealing solar energy generation technology. TES stores heat during the daytime and releases it in the nighttime. As a result, CSP can produce continuously even at night. Storing heat by TES makes CSP a unique technology among various renewable energy sources which often suffer from the intermittency of energy supply (e.g., wind turbines without wind, photovoltaics at night, etc.). The energy conversion efficiency of CSP is directly related to the properties of the TES medium. Binary or ternary mixtures of molten salts (Solar Salt) are commonly used as the TES in CSP due to its high-temperature stability. Enhancing the thermophysical properties of the molten salt medium can significantly improve TES performance. Various studies have reported the anomalous specific heat enhancement of molten salt-based nanofluids. However, the underlying mechanism for this enhancement was yet discovered. In this study, the effect of different synthesis conditions on the resultant specific heat capacity of molten salt-based nanofluids was investigated. Several molten salt nanofluids (NaNO3–KNO3 with SiO nanoparticles at 1 wt. % concentration) were prepared at different thermal cycling conditions and their thermal performance was characterized by a differential scanning calorimeter (DSC).
3D bioprinting dual-factor releasing and gradient-structured constructs ready to implant for anisotropic cartilage regeneration
Authors: Sun Ye , You Yongqing , Jiang Wenbo , Wang Bo , Wu Qiang , Dai Kerong
Published: September 2020

3D bioprinting helps to reconstruct your broken knee.
Cost-effective priorities for the expansion of global terrestrial protected areas: Setting post-2020 global and national targets
Authors: Yang Rui , Cao Yue , Hou Shuyu , Peng Qinyi , Wang Xiaoshan , Wang Fangyi , Tseng Tz-Hsuan , Yu Le , Carver Steve , Convery Ian , Zhao Zhicong , Shen Xiaoli , Li Sheng , Zheng Yaomin , Liu Han , Gong Peng , Ma Keping
Published: September 2020

Cost-effective zones for the expansion of global terrestrial protected areas are identified.
Targeting leukemia-specific mutations
Authors: Kanakry Christopher G.
Published: September 2020

T cells can recognize neoantigens derived from protein products of characteristic genetic fusions and thereby specifically target leukemia cells.
ylm
Has More than a (Z Anchor) Ring to It!
Authors: White Maria L. , Eswara Prahathees J.
Published: September 2020

The division and cell wall (
dcw
) cluster is a highly conserved region of the bacterial genome consisting of genes that encode several cell division and cell wall synthesis factors, including the central division protein FtsZ. The region immediately downstream of
ftsZ
encodes the
ylm
genes and is conserved across diverse lineages of Gram-positive bacteria and
Cyanobacteria
. In some organisms, this region remains part of the
dcw
cluster, but in others, it appears as an independent operon.
Draft Genome Sequence of Collimonas pratensis Strain PMB3(1), an Effective Mineral-Weathering and Chitin-Hydrolyzing Bacterial Strain
Authors: Picard Laura , Oger Philippe , Turpault Marie-Pierre , Uroz Stéphane
Published: September 2020

We announce the draft genome sequence of
Collimonas pratensis
PMB3(1), isolated from the
Scleroderma citrinum
mycorrhizosphere. In addition to its mineral-weathering effectiveness and antifungal activity, this strain is characterized by genomic features that give it great potential as a biocontrol and plant growth-promoting agent in nutrient-poor soils.
Draft Genome Sequence for
Frankia
sp. Strain BMG5.11, a Nitrogen-Fixing Bacterium Isolated from Elaeagnus angustifolia
Authors: Ghodhbane-Gtari Faten , Swanson Erik , Gueddou Abdellatif , Simpson Stephen , Morris Krystalynne , Thomas W. Kelley , Gtari Maher , Tisa Louis S.
Published: September 2020

Frankia
sp. strain BMG5.11, which was isolated from
Elaeagnus angustifolia
nodules, is able to infect other actinorhizal plants, including
Elaeagnaceae
,
Rhamnaceae
,
Colletieae
,
Gymnostoma
, and
Myricaceae
. Here, we report the 11.3-Mbp draft genome sequence of
Frankia
sp. strain BMG5.11, with a G+C content of 69.9% and 9,926 candidate protein-encoding genes.
Can simulators be applied to improve cataract surgery training: a systematic review
Authors: Ahmed Taha Muneer , Hussain Badrul , Siddiqui M A Rehman
Published: September 2020

Objective

The purpose of this paper was to conduct a systematic review of existing literature on simulation-based training of cataract surgery. Available literature was evaluated and projections on how current findings could be applied to cataract surgery training were summarised. The quality of included literature was also assessed.

Methods and analysis

The PubMed, Embase and Cochrane Library databases were searched for articles pertaining to simulation training in cataract surgery on 18 November 2019. Selected articles were qualitatively analysed.

Results

A total of 165 articles were identified out of which 10 met inclusion criteria. Four studies reported construct validity of the EyeSi simulator. Six studies demonstrated improved surgical outcomes corresponding to training on the simulator. Quality assessment of included studies was satisfactory.

Conclusion

Current studies on simulation training in cataract surgery all point towards it being an effective training tool with low risk of study biases confounding this conclusion. As technology improves, surgical training must embrace and incorporate simulation technology in training.
Higher order asymptotics for large deviations — Part II
Authors: Fernando Kasun , Hebbar Pratima
Published: September 2020

We obtain asymptotic expansions for the large deviation principle (LDP) for continuous time stochastic processes with weakly-dependent increments. As a key example, we show that additive functionals of solutions of stochastic differential equations (SDEs) satisfying Hörmander condition on a [Formula: see text]-dimensional compact manifold admit these asymptotic expansions of all orders.
Speaking Your Mind: Using elements of narrative storytelling in eLearning
Authors: Jennings Chris
Published: September 2020

To compensate for the lack of human presence in online courses, consider adding narrative story elements to your eLearning that situates the learner in immersive, real-world scenarios. Framing learning in the context of relatable stories can add tremendous value and enjoyment to students' instruction. Employ an appropriate course voice that attracts users to the content, inviting them to explore, rather than overwhelming them with information.
Five Ways to Flip the Online Classroom on Its Head
Authors: Winger Amy
Published: September 2020

While online higher education learning has increased in availability and popularity, documented best practices have been slow to emerge. One learning practice showing promise is flipped classroom design. Research indicates higher-education flipped classrooms are associated with improved student retention and learner retention of content. With various online practices available to instructors, it is important to choose flipping practices that are supported through research while being attuned to the nature of online learning. Bloom's taxonomy provides a framework for creating active learning opportunities in the online classroom to strive to improve retention of both students and learning.