bluuebunny/crossref_metadata_2025 huggingface dataset:
Diagnostic performance and prognostic value of elastography in patients with biliary atresia and after hepatic portoenterostomy: protocol for a systematic review and meta-analysis
Authors: Yan Hualin , Du Lanxin , Zhou Jiaojiao , Li Yan , Lei Jing , Liu Juxian , Luo Yan
Published: February 2021

Introduction

Biliary atresia (BA) is a life-threatening disease with persistent neonatal cholestasis and progressive liver fibrosis. Timely non-invasive diagnosis of BA can result in early hepatic portoenterostomy (HPE) and better prognosis. Quantitative elastography enables the non-invasive measurement of liver stiffness. However, the studies on elastography methods in the diagnosis of BA and the prediction of post-HPE outcomes vary in their results and have small sample sizes. Thus, we propose this systematic review and meta-analysis to obtain comprehensive evidence on the value of elastography in BA.

Methods and analysis

We will search the PubMed, Embase and the Cochrane Central Register of Controlled Trials databases for studies evaluating the diagnostic performance of elastography in patients with BA and the prognostic value of postoperative elastography, from inception to 31 December 2020. We plan to use the Quality Assessment of Diagnostic Accuracy Studies-2 list and the Quality In Prognosis Studies tool to assess the risk of bias in the included studies and the study quality. We will evaluate the diagnostic performance of elastography by synthesising the pooled sensitivity, pooled specificity, pooled positive likelihood ratio, pooled negative likelihood ratio, pooled diagnostic OR and summary receiver operating characteristic curve using Meta-Disc V.1.4. We will evaluate the predictive value of elastography after HPE by synthesising the pooled correlation coefficient and pooled OR of prognostic outcomes using STATA V.14. The funnel plot and Egger’s test will be used to evaluate the potential publication bias. Sensitivity analysis will be conducted by examining the estimated effects of individual studies.

Ethics and dissemination

As this study is a meta-analysis based on previously published literature, ethical approval is not necessary according to the ethics committee of West China Hospital, Sichuan University. The results of this study will be published in a peer-reviewed journal.

PROSPERO registration number

CRD42020162055.
Clinical Nursing Introduction Program for new graduate nurses in Sweden: study protocol for a prospective longitudinal cohort study
Authors: Johansson Anita , Berglund Mia , Kjellsdotter Anna
Published: February 2021

Introduction

High levels of nursing turnover represent a problem for healthcare organisations and patient safety. Experiences during the first years in the nursing profession have a significant impact on nurses’ future decisions concerning their careers. Nurses at the start of their professional career need to practise their hands-on skills as well as their theoretical knowledge. In addition, new graduate nurses need regular support and opportunities to reflect on experiences in their new profession. The aim of the present study is to describe the Clinical Nursing Introduction Program (CNIP) and present a study design in which the programme is used to support new graduate nurses’ transition into the nursing profession.

Method and analysis

The present study examines the CNIP at a general hospital in southwest Sweden, which lasts for 14 months. The programme has a unique profile based on a person-centred approach and consists of five components: employment and organisation, a compulsory introduction week, two placements in different clinical settings, education days and process-oriented nursing supervision. The present study presents a protocol for a prospective longitudinal cohort study, using qualitative and quantitative methods in the collection and analysis of data. Measurements will include data collection between 2019 and 2023 when the nurses start the CNIP (baseline) and then after 1 and 2 years.

Ethics and dissemination

This study has been approved by the Regional Ethical Review Board in Gothenburg (Dnr 1056-18). Study findings will be presented at national and international conferences and published in peer-reviewed journals.

Trial registration number

273573 (https://www.researchweb.org/is/vgr).
Burn-out syndrome in Spanish internists during the COVID-19 outbreak and associated factors: a cross-sectional survey
Authors: Macía-Rodríguez Cristina , Alejandre de Oña Álvaro , Martín-Iglesias Daniel , Barrera-López Lucía , Pérez-Sanz María Teresa , Moreno-Diaz Javier , González-Munera Adriana
Published: February 2021

Objectives

The objective of this study is to evaluate the impact of the COVID-19 outbreak on mental health and burn-out syndrome in Spanish internists and the factors that could be related to its appearance.

Design

We performed an observational, cross-sectional, descriptive study for which we designed a survey that was distributed in May 2020.

Setting

We included internists who worked in Spain during the COVID-19 outbreak.

Participants

A total of 1015 internists responded to the survey. Of those 62.9% were women.

Results

Of 1015 people, 58.3% presented with high emotional exhaustion, 61.5% had a high level of depersonalisation and 67.6% reported low personal fulfilment. 40.1% presented with the 3 criteria described, and therefore burn-out syndrome.

Burn-out syndrome was independently related to the management of patients with SARS-CoV-2 (HR: 2.26; 95% CI 1.15 to 4.45), the lack of availability of personal protective equipment (HR: 1.41; 95% CI 1.05 to 1.91), increased responsibility (HR: 2.13; 95% CI 1.51 to 3.01), not having received financial compensation for overtime work (HR: 0.43; 95% CI 0.31 to 0.62), not having rested after 24-hour shifts (HR: 1.61; 95% CI 1.09 to 2.38), not having had holidays in the previous 6 months (HR: 1.36; 95% CI 1.01 to 1.84), consumption of sleeping pills (HR: 1.83; 95% CI 1.28 to 2.63) and higher alcohol intake (HR: 1.95; 95% CI 1.39 to 2.73).

Conclusions

During the COVID-19 outbreak, 40.1% of Internal Medicine physicians in Spain presented with burn-out syndrome, which was independently related to the assistance of patients with SARS-CoV-2, overworking without any compensation and the fear of being contagious to their relatives. Therefore, it is imperative to initiate programmes to prevent and treat burn-out in front-line physicians during the COVID-19 outbreak.
Remodelling of a regional emergency hub in response to the COVID-19 outbreak in Emilia-Romagna
Authors: Gamberini Lorenzo , Coniglio Carlo , Cilloni Nicola , Semeraro Federico , Moro Federico , Tartaglione Marco , Chiarini Valentina , Lupi Cristian , Bua Vincenzo , Gordini Giovanni
Published: February 2021

Emilia-Romagna was one of the most affected Italian regions during the COVID-19 outbreak in February 2020. We describe here the profound regional, provincial and municipal changes in response to the COVID-19 pandemic, to cope with the numbers of patients presenting with COVID-19 illness, as well as coping with the ongoing need to care for patients presenting with non-COVID-19 emergencies. We focus on the structural and functional changes in one particular hospital within the city of Bologna, the regional capital, which acted as the central emergency hub for time-sensitive pathologies for the province of Bologna. Finally, we present the admissions profile to our emergency department in relation to the massive increase of infected patients observed in our region as well as the organisational response to prepare for the second wave of the pandemic.
Vaping and cardiac disease
Authors: Shahandeh Negeen , Chowdhary Harshika , Middlekauff Holly R
Published: February 2021

Tobacco cigarette smoking is the most prevalent reversible risk factor for cardiovascular disease in the USA. Electronic cigarettes, invented as an alternative nicotine source for smokers unable or unwilling to stop smoking, have gained skyrocketing popularity, but their cardiovascular risk remains uncertain. Although data recently analysed in a Cochran report do support their superior effectiveness to other forms of nicotine replacement therapies for smoking cessation, electronic cigarettes are also frequently used by non-smokers—especially high school students. There are no long-term outcome studies on the cardiovascular risk of vaping electronic cigarettes, but the effects of electronic cigarettes on known risk factors for cardiovascular disease, including neurohumoural activation, oxidative stress and inflammation, endothelial function and thrombosis, have been studied. In this review, we summarise evidence in humans that supports the notion that while electronic cigarettes may be less harmful than traditional cigarettes, they are not harmless. Additionally, the increasing popularity of vaping marijuana with its unknown cardiovascular risks as well as the outbreak in 2019 of EVALI (electronic cigarette, or vaping, product use-associated lung injury) related to bootlegged vaping products raise further concerns. Before physicians can confidently advise their smoking patients about the role of electronic cigarettes as a means of smoking cessation to lower cardiovascular risk, improved regulation and quality control is necessary.
Antibody profiling of patients with prostate cancer reveals differences in antibody signatures among disease stages
Authors: Potluri Hemanth K , Ng Tun Lee , Newton Michael A , Zhang Jin , Maher Christopher A , Nelson Peter S , McNeel Douglas G
Published: February 2021

Background

Previous studies of prostate cancer autoantibodies have largely focused on diagnostic applications. So far, there have been no reports attempting to more comprehensively profile the landscape of prostate cancer-associated antibodies. Specifically, it is unknown whether the quantity of antibodies or the types of proteins recognized change with disease progression.

Methods

A peptide microarray spanning the amino acid sequences of the gene products of 1611 prostate cancer-associated genes was synthesized. Serum samples from healthy male volunteers (n=15) and patients with prostate cancer (n=85) were used to probe the array. These samples included patients with various clinical stages of disease: newly diagnosed localized prostate cancer (n=15), castration-sensitive non-metastatic prostate cancer (nmCSPC, n=40), castration-resistant non-metastatic prostate cancer (n=15) and castration-resistant metastatic disease (n=15). The patients with nmCSPC received treatment with either standard androgen deprivation therapy (ADT) or an antitumor DNA vaccine encoding prostatic acid phosphatase. Serial sera samples from these individuals were also used to probe the array, to secondarily determine whether this approach could be used to detect treatment-related changes.

Results

We demonstrated that this peptide array yielded highly reproducible measurements of serum IgG levels. We found that the overall number of antibody responses did not increase with disease burden. However, the composition of recognized proteins shifted with clinical stage of disease. Our analysis revealed that the largest difference was between patients with castration-sensitive and castration-resistant disease. Patients with castration-resistant disease recognized more proteins associated with nucleic acid binding and gene regulation compared with men in other groups. Our longitudinal data showed that treatments can elicit antibodies detectable by this array, and notably vaccine-treated patients developed increased responses to more proteins over the course of treatment than did ADT-treated patients.

Conclusions

This study represents the largest survey of prostate cancer-associated antibodies to date. We have been able to characterize the classes of proteins recognized by patients and determine how they change with disease burden. Our findings further demonstrate the potential of this platform for measuring antigen spread and studying responses to immunomodulatory therapies.
Suicide in welfare support workers: a retrospective mortality study in Australia 2001–2016
Authors: Maheen Humaira , Dimov Stefanie , Spittal Matthew J , King Tania L
Published: February 2021

Objectives

Employees working in the welfare and healthcare industry have poorer mental health than other occupational groups; however, there has been little examination of suicide among this group. In this study, we examined suicide rates among welfare support workers and compared them to other occupations in Australia.

Methods

We used data from the National Coroners Information System to obtain suicide deaths between the years 2001 and 2016. Using the Australian standard population from 2001 and Census data from 2006, 2011 and 2016, we calculated age-standardised suicide rates and rate ratios to compare suicide rates across different occupational groups.

Results

Overall, the age-standardised suicide rate of welfare support workers was 8.6 per 100 000 people. The gender-stratified results show that male welfare support workers have a high suicide rate (23.8 per 100 000 people) which is similar to male social workers and nurses (25.4 per 100 000). After adjusting for age and year of death, both males (rate ratio 1.48, 95% CI 1.23 to 1.78) and female welfare support workers (rate ratio 1.49, 95% CI 1.20 to 1.86) have higher suicide rate ratios compared with the reference group (excluding occupations from the comparison groups).

Conclusion

The age-standardised suicide rates of male welfare support workers are comparable to occupations which have been identified as high-risk occupations for suicide. Both female and male welfare support workers are at elevated risk of suicide compared with other occupations. Further research is required to understand the drivers of the elevated risk in this group.
Simplified bedside assessment of pulmonary gas exchange in very preterm infants at 36 weeks’ postmenstrual age
Authors: Stoecklin Benjamin , Choi Y Jane , Rakshasbhuvankar Abhijeet , Svedenkrans Jenny , Jones Gareth , Pillow Jane
Published: February 2021

Introduction

We aimed to develop and validate a prediction table for a simplified measure of rightward shift of the fetal oxyhaemoglobin saturation (SpO
2
) versus inspired oxygen pressure (
P
I
O
2
) curve as an objective marker of lung disease severity in very preterm infants, independent of unit altitude or oxygen prescribing policies.

Methods

Very preterm infants (n=219) had an oxygen reduction test at median (IQR) test age of 35
4
(34
5
–36
0
) weeks’ postmenstrual age (PMA). Shift was derived from at least three paired SpO
2
versus
P
I
O
2
measurements using a computer algorithm, using the fetal oxyhaemoglobin dissociation curve as the reference. Linear regression of resultant shift values enabled construction of a table to predict shift using a single paired SpO
2
versus
P
I
O
2
measurement, validated subsequently in a separate infant cohort using Bland-Altman analysis. Receiver operating curve analysis provided threshold values equating to a clinical diagnosis of mild bronchopulmonary dysplasia (BPD) or moderate to severe BPD.

Results

The median (IQR) age of 63 infants in the validation cohort was 36
0
(35
6
–36
2
) weeks’ PMA. Mean difference (95% CI) between predicted and measured shift was 2.1 (−0.8% to 4.9%) with wide limits of agreement (−20.7% to 24.8%). Predicted shift >10.1 kPa identified mild BPD with 71% sensitivity and 88% specificity while values>13.0 kPa identified moderate to severe BPD with 81% sensitivity and 100% specificity.

Discussion

Shift predicted from a single paired SpO
2
versus
P
I
O
2
measurement using our validated table enables objective bedside screening of lung disease severity in very preterm infant cohorts at 36 weeks’ PMA.
Incorporating age improves the Glasgow Coma Scale score for predicting mortality from traumatic brain injury
Authors: Salottolo Kristin , Panchal Ripul , Madayag Robert M , Dhakal Laxmi , Rosenberg William , Banton Kaysie L , Hamilton David , Bar-Or David
Published: February 2021

Background

The Glasgow Coma Scale (GCS) score has been adapted into categories of severity (mild, moderate, and severe) and are ubiquitous in the trauma setting. This study sought to revise the GCS categories to account for an interaction by age and to determine the discrimination of the revised categories compared with the standard GCS categories.

Methods

The American College of Surgeons National Trauma Data Bank registry was used to identify patients with traumatic brain injury (TBI; ICD-9 codes 850–854.19) who were admitted to participating trauma centers from 2010 to 2015. The primary exposure variables were GCS score and age, categorized by decade (teens, 20s, 30s…, 80s). In-hospital mortality was the primary outcome for examining TBI severity/prognostication. Logistic regression was used to calculate the conditional probability of death by age decade and GCS in a development dataset (75% of patients). These probabilities were used to create a points-based revision of the GCS, categorized as low (mild), moderate, and high (severe). Performance of the revised versus standard GCS categories was compared in the validation dataset using area under the receiver operating characteristic (AUC) curves.

Results

The final population included 539,032 patients with TBI. Age modified the performance of the GCS, resulting in a novel categorization schema for each age decile. For patients in their 50s, performance of the revised GCS categories mirrored the standard GCS categorization (3–8, 9–12, 13–15); all other revised GCS categories were heavily modified by age. Model validation demonstrated the revised GCS categories statistically significantly outperformed the standard GCS categories at predicting mortality (AUC: 0.800 vs 0.755, p<0.001). The revised GCS categorization also outperformed the standard GCS categories for mortality within pre-specified subpopulations: blunt mechanism, isolated TBI, falls, non-transferred patients.

Discussion

We propose the revised age-adjusted GCS categories will improve severity assessment and provide a more uniform early prognostic indicator of mortality following traumatic brain injury.

Level of evidence

III epidemiologic/prognostic.
Decreased adult trauma admission volumes and changing injury patterns during the COVID-19 pandemic at 85 trauma centers in a multistate healthcare system
Authors: Berg Gina M , Wyse Ransom J , Morse Jennifer L , Chipko John , Garland Jeneva M , Slivinski Andrea , Lieser Mark , Biswas Saptarshi , Carrick Matthew M , Rhodes Heather , Acuna David , Watts Dorraine D , Wilson Nina Y , Shen Yan , Deas Shenequa , Fakhry Samir M
Published: February 2021

Background

Reports indicate social distancing guidelines and other effects of the COVID-19 pandemic impacted trauma patient volumes and injury patterns. This report is the first analysis of a large trauma network describing the extent of these impacts. The objective of this study was to describe the effects of the COVID-19 pandemic on patient volumes, demographics, injury characteristics, and outcomes.

Methods

For this descriptive, multicenter study from a large, multistate hospital network, data were collected from the system-wide centralized trauma registry and retrospectively reviewed to retrieve patient information including volume, demographics, and outcomes. For comparison, patient data from January through May of 2020 and January through May of 2019 were extracted.

Results

A total of 12 395 trauma patients (56% men, 79% white, mean age 59 years) from 85 trauma centers were included. The first 5 months of 2020 revealed a substantial decrease in volume, which began in February and continued into June. Further analysis revealed an absolute decrease of 32.5% in patient volume in April 2020 compared with April 2019 (4997 from 7398; p<0.0001). Motor vehicle collisions decreased 49.7% (628 from 1249). There was a statistically significant increase in injury severity score (9.0 vs. 8.3; p<0.001). As a proportion of the total trauma population, blunt injuries decreased 3.1% (87.3 from 90.5) and penetrating injuries increased 2.7% (10.0 from 7.3; p<0.001). A significant increase was found in the proportion of patients who did not survive to discharge (3.6% vs. 2.8%; p=0.010; absolute decrease: 181 from 207).

Discussion

Early phases of the COVID-19 pandemic were associated with a 32.5% decrease in trauma patient volumes and altered injury patterns at 85 trauma centers in a multistate system. This preliminary observational study describes the initial impact of the COVID-19 pandemic and warrants further investigation.

Level of evidence

Level II (therapeutic/care management).
A simple model for viscoelastic crack propagation
Authors: Persson B. N. J.
Published: February 2021

When a crack propagates in a viscoelastic solid, energy dissipation can occur very far from the crack tip where the stress field may be very different from the $$r^{-1/2}$$

r

-
1
/
2

singular form expected close to the crack tip. Most theories of crack propagation focus on the near crack tip region. Remarkable, here I show that a simple theory which does not account for the nature of the stress field in the near crack tip region results in a crack propagation energy in semiquantitative agreement with a theory based on the stress field in the near crack tip region. I consider both opening and closing crack propagation and show that for closing crack propagation in viscoelastic solids, some energy dissipation processes must occur in the crack tip process zone. The theory is illustrated by new experimental results for the adhesive interaction between a silica glass ball and a silicone rubber surface.

Graphic abstract
EFFECTS OF PARTICLE SIZE AND SINTERING TEMPERATURE ON SUPERELASTICITY BEHAVIOR OF NiTi SHAPE MEMORY ALLOY USING NANOINDENTATION
Authors: VELMURUGAN C. , SENTHILKUMAR V.
Published: February 2021

The present study investigates the superelasticity properties of spark plasma sintered (SPS) nickel titanium shape memory alloy (NiTi SMA) with the influence of sintering temperature and particle size. The nanoindentation is conducted on the surface of the NiTi SMA at various loads such as 100, 300 and 500[Formula: see text]mN. The nanoindentation technique determines the quantitative results of elasto-plastic properties such as depth recovery in the form of superelasticity, stiffness, hardness and work recovery ratio from load–depth ([Formula: see text]–[Formula: see text]) data during loading and unloading of the indenter. Experimental findings show that the depth and work recovery ratio increases with the decrease of indentation load and particle size. In contrast, increasing the sintering temperature exhibited a better depth and work recovery due to the removal of pores which could enhance the reverse transformation. The contact stiffness is influenced by [Formula: see text] which leads to attain a maximum stiffness at the highest load (500[Formula: see text]mN) and particle size (45[Formula: see text][Formula: see text]m) along with the lowest sintering temperature (700∘C). NiTi alloy exhibited a maximum hardness of 9.46[Formula: see text]GPa when subjected to indent at the lowest load and particle size sintered at 800∘C. The present study reveals a better superelastic behavior in NiTi SMA by reducing the particle size and indentation load associated with the enhancement of sintering temperature.
Kinetic Monte Carlo simulation of random deposition and scaling behavior with respect to the germination length
Authors: Saoudi Abdenour , Aissani Linda , Sorba Grégoire , Chinesta Francisco
Published: February 2021

This work aims at analyzing the scaling behavior and develop correlations during surface growing for different germination lengths. The surface growing by random deposition is simulated using a kinetic Monte Carlo approach, by considering different germination lengths. Different surface descriptors are extracted, among them the roughness and the correlation. The former allows extracting the scaling behavior, while the latter proves the existence of correlations independent of the system size but dependent on the germination length. Moreover, as in the case of random deposition with a null germination length, the growing roughness never saturates.
Quasi-Band-Limited Coronagraph for Extended Sources
Authors: Loutsenko Igor , Yermolayeva Oksana
Published: February 2021

We propose a class of graded coronagraphic “amplitude” image masks for a high throughput Lyot-type coronagraph that transmits light from an annular region around an extended source and suppresses light, with extremely high ratio, from elsewhere. The interior radius of the region is comparable with its exterior radius. The masks are designed using an idea inspired by approach due M. J. Kuchner and W. A. Traub (“band-limited” masks) and approach to optimal apodization by D. Slepian. One potential application of our masks is direct high-resolution imaging of exo-planets with the help of the Solar Gravitational Lens, where apparent radius of the “Einstein ring” image of a planet is of the order of an arc-second and is comparable with the apparent radius of the sun and solar corona.
Understanding the Properties of Phenazine Mediators that Promote Extracellular Electron Transfer in Escherichia coli
Authors: Simoska Olja , Gaffney Erin M. , Lim Koun , Beaver Kevin , Minteer Shelley D.
Published: February 2021

The ability to establish successful and efficient extracellular electron transfer (EET) between bacteria and electrode surfaces is critical for the development of mediated microbial electrochemical technologies. Here, we describe a phenazine-based mediator system to facilitate electron transfer from the model bacterium Escherichia coli during glucose metabolism. Phenazine redox mediators were experimentally evaluated, demonstrating distinct mediated currents, dependent on mediator structure. Our results show that the choice of a mediator with the appropriate redox potential is not the single aspect to consider when rationally designing future mediator-based EET systems.
Four-Dimensional Identical-Location X-ray Imaging of Fuel Cell Degradation during Start-Up/Shut-Down Cycling
Authors: Stoll Jonas , Orfino Francesco P. , Dutta Monica , Kjeang Erik
Published: February 2021

In this work, local electrode degradation effects from start-up/shut-down cycling of polymer electrolyte fuel cells are visualized using X-ray tomographic imaging of specialized, miniature fuel cell hardware. This combination enables non-invasive in situ tracking of the same cathode catalyst layer domain throughout various degradation stages in four dimensions. Critical, localized regions are identified within the cathode catalyst layer where progressive structural deterioration occurs from carbon support corrosion leading to thinning and collapse of the material. A greater structural change is observed under the landing area than under the channels due to delayed resident gas purge. This finding differs from the results of voltage cycling accelerated stress test, where more structural change was observed under the channel area than the landing area. However, overall similarities in degradation and performance loss supports the use of voltage cycling for accelerated degradation studies. A direct correlation between the structural deterioration and the electrochemical performance reduction of the fuel cell is found. In addition, reduced reactant gas flow in a restricted anode flow channel enhances the local cathode degradation due to delayed gas purge. However, no influence on the degradation is observed in a cell with intentional anode/cathode channel misalignment, compared to generic test cells.
Influence of Fluoride Ions on the Speciation and Electrochemical Behavior of Th(IV) in Molten LiCl-KCl with a Copper Electrode
Authors: Zhu Tiejian , Huang Wei , Gong Yu
Published: February 2021

The speciation and electrochemical behavior of thorium (IV) fluoride in molten LiCl-KCl with a copper working electrode was investigated. In addition to the reduction of Th(IV) [ThCl6
2− and ThCl7
3−] to metallic thorium, there is a minor peak in the cyclic and square wave voltammagrams that results from the reduction of Th(IV) [ThCl6−xFx
2− and ThCl7−xFx
3−] to metallic thorium on the basis of the square wave voltammetry and X-ray diffraction results. This is also supported by the formation of metallic thorium deposits upon potentiostatic electrolysis. In addition, the diffusion coefficient and diffusion activation energy of Th(IV) with a copper electrode was determined, which show similarity in comparison to those obtained using inert working electrodes.
A novel murine muscle loading model to investigate Achilles musculotendinous adaptation
Authors: Rezvani Sabah N. , Nichols Anne E. C. , Grange Robert W. , Dahlgren Linda A. , Brolinson P. Gunnar , Wang Vincent M.
Published: February 2021

We introduce a novel mouse model of hindlimb muscle loading designed to achieve a tissue-targeted therapeutic exercise. This innovative model allows for application of muscle loading “doses,” coupled with ankle dorsiflexion and plantarflexion, inspired by human loading clinical treatment. Our model facilitates future investigation of mechanisms whereby rehabilitative muscle loading promotes healing of Achilles tendon injuries.
Measuring the mechanical input impedance of the respiratory system with breath-driven flow oscillations
Authors: Roy Gregory S. , Daphtary Nirav , Johnson Olivia , Dixon Anne E. , Kaminsky David A. , Bates Jason H.T.
Published: February 2021

The technique of oscillometry for measuring the mechanical input impedance of the respiratory system is gaining traction as a clinical diagnostic tool, but the portability of existing commercially available devices is limited by the size and weight of oscillator motors and power supplies. We show that impedance can be measured by oscillations in mouth pressure and flow generated by mucus-clearing devices that are powered by the subject’s own respiratory flow. This principle might thus be employed in lightweight ambulatory oscillometry devices.
Magnetoencephalography: physics, techniques, and applications in the basic and clinical neurosciences
Authors: Kim Junseok A. , Davis Karen D.
Published: February 2021

Magnetoencephalography (MEG) is a technique used to measure the magnetic fields generated from neuronal activity in the brain. MEG has a high temporal resolution on the order of milliseconds and provides a more direct measure of brain activity when compared with hemodynamic-based neuroimaging methods such as magnetic resonance imaging and positron emission tomography. The current review focuses on basic features of MEG such as the instrumentation and the physics that are integral to the signals that can be measured, and the principles of source localization techniques, particularly the physics of beamforming and the techniques that are used to localize the signal of interest. In addition, we review several metrics that can be used to assess functional coupling in MEG and describe the advantages and disadvantages of each approach. Lastly, we discuss the current and future applications of MEG.
Evaluation of the Effect of Hydroethanolic Root Extract and Solvent Fractions of Cyphostemma adenocaule (Steud. ex A. Rich) Descoings ex Wild & Drummond on Cell-Mediated Immune Response and Blood Cell Count in Mice
Authors: Abebe Dehnnet , Periasamy Gomathi , Karim Aman , Bitew Helen
Published: February 2021

Introduction. Cyphostemma adenocaule (Steud. ex A. Rich) Descoings ex wild & Drummond (Vitaceae) has been used in traditional medicine for the management of various immunological and hematological disorders in different areas of Ethiopia and the rest of the world. In Ethiopia, the plant is used for the management of enlarged spleen, rabies virus, helminthic infection, snake bite, and various types of tumors. Objective. To evaluate the effect of hydroethanolic root extract and solvent fractions of Cyphostemma adenocaule on cell-mediated immunity (delayed-type hypersensitivity), organ index (spleen and liver), and blood cell count in Swiss albino mice. Materials and Methods. Acute oral toxicity test was conducted using nulliparous and nonpregnant Swiss albino mice following OECD 425 limit test method. Delayed-type hypersensitivity model was used to evaluate the effect on cell-mediated immunity. The experimental animals were divided into twelve groups which were sensitized and challenged with sheep red blood cells on day 0 and day 7, respectively. Levamisole 50 mg/kg was used as stimulant control, whereas cyclophosphamide 30 mg/kg was used as suppressant control. Hydroethanolic root extract (100 mg/kg, 200 mg/kg, and 400 mg/kg), aqueous fraction (100 mg/kg, 200 mg/kg, and 400 mg/kg), and n-butanol fraction (100 mg/kg, 200 mg/kg, and 400 mg/kg) were administered for seven days. The paw volume was measured using a digital plethysmometer before challenge and 24 hours after challenge. Blood was collected, and organs (spleen and liver) were isolated from each challenged mouse to determine blood cell count and organ index, respectively. Results. No mortality and noticeable behavioral changes were observed among all mice receiving hydroethanolic root extract and solvent fractions at a dose of 2000 mg/kg. Hydroethanolic root extract and solvent fractions of Cyphostemma adenocaule showed enhancement of delayed-type hypersensitivity, organ index, and blood cell count. Hydroethanolic root extract at a dose of 400 mg/kg showed the highest and statistically significant stimulation of delayed-type hypersensitivity (0.123 ± 0.010) and blood cell count compared to the vehicle. Conclusion. Hydroethanolic root extract and solvent fractions of Cyphostemma adenocaule showed a stimulatory effect on cell-mediated immunity and hematopoiesis.
Current State of Non-wearable Sensor Technologies for Monitoring Activity Patterns to Detect Symptoms of Mild Cognitive Impairment to Alzheimer’s Disease
Authors: Narasimhan Rajaram , G. Muthukumaran , McGlade Charles
Published: February 2021

Mild cognitive impairment (MCI) could be a transitory stage to Alzheimer’s disease (AD) and underlines the importance of early detection of this stage. In MCI stage, though the older adults are not completely dependent on others for day-to-day tasks, mild impairments are seen in memory, attention, etc., subtly affecting their daily activities/routines. Smart sensing technologies, such as wearable and non-wearable sensors, coupled with advanced predictive modeling techniques enable daily activities/routines based early detection of MCI symptoms. Non-wearable sensors are less intrusive and can monitor activities at naturalistic environment with no interference to an individual’s daily routines. This review seeks to answer the following questions: (1) What is the evidence for use of non-wearable sensor technologies in early detection of MCI/AD utilizing daily activity data in an unobtrusive manner? (2) How are the machine learning methods being employed in analyzing activity data in this early detection approach? A systematic search was conducted in databases such as IEEE Explorer, PubMed, Science Direct, and Google Scholar for the papers published from inception till March 2019. All studies that fulfilled the following criteria were examined: a research goal of detecting/predicting MCI/AD, daily activities data to detect MCI/AD, noninvasive/non-wearable sensors for monitoring activity patterns, and machine learning techniques to create the prediction models. Out of 2165 papers retrieved, 12 papers were eligible for inclusion in this review. This review found a diverse selection of aspects such as sensors, activity domains/features, activity recognition methods, and abnormality detection methods. There is no conclusive evidence on superiority of one or more of these aspects over the others, especially on the activity feature that would be the best indicator of cognitive decline. Though all these studies demonstrate technological developments in this field, they all suggest it is far in the future it becomes an effective diagnostic tool in real-life clinical practice.
Radar Emitter Individual Identification Based on Convolutional Neural Network Learning
Authors: Sun Wei , Wang Lihua , Sun Songlin
Published: February 2021

Radar Emitter Individual Identification is a key technology in modern electronic radar systems. This paper will focus on Radar Emitter Individual Identification (REII). Based on the advantages of Empirical Mode Decomposition (EMD) and bispectrum in signal processing, we propose an REII method based on the CNN. Firstly, the radar emitter signal is preprocessed. Secondly, the Hilbert–Huang Transform (HHT) spectrum and bispectrum are combined to form an image of the signal. Finally, in order to avoid loss of information and achieve the potential identification performance improvement, the signal image obtained is identified by the optimized CNN. Experimental results based on the measured signals show that the proposed method has high identification accuracy and is capable of meeting real-time identification requirements. The deep-learning-based identification method proposed in this paper has strong generalization ability and adaptability, which provides a new way for REII.
The Therapeutic Potential of Inflamed Gingiva-Derived Mesenchymal Stem Cells in Preclinical Studies: A Scoping Review of a Unique Biomedical Waste
Authors: Al-Qadhi Gamilah , Al-Rai Sarah , Hafed Layla
Published: February 2021

Searching for considerable abundance, simple, and accessible sources in stem cell-based therapy opens the door for isolation of a new population of oral/dental stem cells known as inflamed gingiva-derived mesenchymal stem cells, which have recently come to light with promising therapeutic potential in tissue regenerative therapy. Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews guidelines, this scoping review is aimed at highlighting the possible therapeutic potential of inflamed gingiva-derived mesenchymal stem cells in preclinical studies carried out to date and presenting the current evidence depends upon their comparison to the healthy gingiva-derived mesenchymal stem cells or other mesenchymal stem cell sources. A comprehensive electronic search using (PubMed, Embase, Scopus, and Web of Science) databases and a manual search of relevant references were conducted until June 2020. Included studies were assessed using a combination tool, including the guidelines for reporting preclinical in vitro studies on dental materials, which were based on the modification of the Consolidated Standards of Reporting Trial checklist and the guidelines for animal research: reporting of in vivo experiments. The initial research provided 360 articles, with 13 articles that met the inclusion criteria. While most of the included studies lacked randomization, blinding, and sample size calculation, they were designed accurately in other aspects of the guidelines. The results of this scoping review indicated that inflamed gingiva-derived mesenchymal stem cells could be effective in terms of osteogenic differentiation, collagen fiber formation, immunoregulation, migration capacity, and testing of dental material and may present a reliable alternative source for healthy gingiva-derived mesenchymal stem cells.
iTRAQ‐Based Quantitative Proteomics Indicated Nrf2/OPTN‐Mediated Mitophagy Inhibits NLRP3 Inflammasome Activation after Intracerebral Hemorrhage
Authors: Cheng Yijun , Liu Mingjian , Tang Hao , Chen Bin , Yang Guoyuan , Zhao Weiguo , Cai Yu , Shang Hanbing
Published: February 2021

Intracerebral hemorrhage‐ (ICH‐) induced secondary brain injury (SBI) is a very complex pathophysiological process. However, the molecular mechanisms and drug targets of SBI are highly intricate and still elusive, yet a clear understanding is crucial for the treatment of SBI. In the current study, we aimed to confirm that nuclear factor‐E2‐related factor 2 (Nrf2)/Optineurin‐ (OPTN‐) mediated mitophagy alleviated SBI by inhibiting nucleotide‐binding oligomerization domain‐like receptor pyrin domain‐containing 3 (NLRP3) inflammasome activation based on the isobaric tag for relative and absolute quantization (iTRAQ) quantification proteomics. Human ICH brain specimens were collected for iTRAQ‐based proteomics analysis. Male Nrf2 wild‐type (WT) and knockout (KO) mice were employed to establish ICH murine models. The survival rate, hematoma volume, neurofunctional outcomes, blood‐brain barrier (BBB) permeability, brain edema, spatial neuronal death, NLRP3 inflammasome, inflammatory response, mitochondrial function, and mitophagy level were evaluated after ICH. The iTRAQ quantification analysis showed that the differentially expressed proteins (DEPs), Nrf2 and NLRP3, were closely associated with the initiation and development of SBI after ICH. The Nrf2 KO mice had a significantly lower survival rate, bigger hematoma volume, worse neurological deficits, and increased BBB disruption, brain edema, and neuronal death when compared with the Nrf2 WT mice after ICH. Furthermore, Nrf2 KO enhanced NLRP3 inflammasome activation and neuroinflammation as evidenced by the NF‐κB activation and various proinflammatory cytokine releases following ICH. Moreover, Nrf2 could interact with and modulate the mitophagy receptor OPTN, further mediating mitophagy to remove dysfunctional mitochondria after ICH. Furthermore, OPTN small interfering RNA (siRNA) increased the NLRP3 inflammasome activation by downregulating mitophagy level and enhancing mitochondrial damage in the Nrf2 WT mice after ICH. Together, our data indicated that Nrf2/OPTN inhibited NLRP3 inflammasome activation, possibly via modulating mitophagy, therefore alleviating SBI after ICH.
Isoegomaketone from Perilla frutescens (L.) Britt Stimulates MAPK/ERK Pathway in Human Keratinocyte to Promote Skin Wound Healing
Authors: Kim Ye-Ram , Nam Bomi , Han Ah-Reum , Kim Jin-Baek , Jin Chang Hyun
Published: February 2021

Skin wound healing is essential for recovery from injury, and delayed or impaired wound healing is a severe therapeutic challenge. Keratinocytes, a major component of the epidermis, play crucial roles in reepithelialization during wound healing including cell proliferation. Recent studies have shown that compounds from natural products have candidates for healing skin injury. Isoegomaketone (IK), isolated from leaves of Perilla frutescens var. crispa (Lamiaceae), has various bioactivities. However, the effect of IK on cutaneous wound healing processes has not been studied yet. In this study, we demonstrated that IK exhibits therapeutic wound healing effects using the human keratinocyte cell line HaCaT. Notably, IK promoted cell proliferation and migration in a dose-dependent manner in vitro, and treatment with 10 μM IK upregulated these processes by approximately 1.5-fold after 24 h compared with the control. IK induced the activation of the MAPK/ERK pathway and cell cycle progression to the S and G2/M phases. Thus, this study demonstrates IK as a potential candidate to upregulate wound healing that may provide therapeutic benefits to patients with delayed wound healing.
Extinction Moment for a Branching Tree Evolution with Birth Rate and Death Rate Both Depending on Age
Authors: Hu Xi , Yan Yun-Zhi , Zheng Zhong-Tuan , Li Hong-Yan , Zhao Hong-Yan
Published: February 2021

In this paper, a branching tree evolution is established, in which the birth rate and the death rate are both dependent on node’s age. The extinction probability and the t-pre-extinction (extinct before time

t

) probability are studied, by which the distribution of the extinction moment can be given. The analytical formula and the approximation algorithm for the distribution of extinction moment are given; furthermore, the analytical formula and the approximation algorithm of extinction probability are given, and a necessary and sufficient condition of extinction with probability 1 is given. It is the first time to study the distribution of extinction time for the branching process with birth rate and the death rate both depending on node’s age, and the results will do great help in the theory of branching process. It is expected to be applied in the fields of biology, genetics, medicine, epidemiology, demography, nuclear physics, actuarial mathematics, algorithm, and data structures, etc.
Research on the Prediction Model of the Friction Coefficient of Asphalt Pavement Based on Tire‐Pavement Coupling
Authors: Yu Miao , Xu Xinquan , Wu Chuanhai , Li Shanqiang , Li Mingxia , Chen Haifeng
Published: February 2021

The correlations between pavement texture and tire pressure with the actual tire‐road contact area were first investigated according to the tire‐road static contact characteristics; on this basis, the influence mechanisms of speed and pavement texture on the pavement friction coefficient were systematically explored from the angle of tire‐road coupling system dynamics via the self‐developed dynamic testing system of tire‐pavement friction. By integrating the above influence factors, the BP neural network method was applied to the regression of the prediction model for the asphalt pavement friction coefficient. Through the comparison between the model measured value and estimated value, their correlation coefficient R2 reached 0.73, indicating that this model is of satisfactory prediction accuracy and applicable to the antiskid design of asphalt pavement.
Intelligent Design of Product Forms Based on Design Cognitive Dynamics and a Cobweb Structure
Authors: Yang Wenjin , Su Jian-Ning , Zhang Shutao , Qiu Kai , Zhang Xinxin
Published: February 2021

Design is a complex, iterative, and innovative process. By traditional methods, it is difficult for designers to have an integral priori design experience to fully explore a wide range of design solutions. Therefore, refined intelligent design has become an important trend in design research. More powerful design thinking is needed in intelligent design process. Combining cognitive dynamics and a cobweb structure, an intelligent design method is proposed to formalize the innovative design process. The excavation of the dynamic mechanism of the product evolution process during product development is necessary to predict next‐generation multi‐image product forms from a larger design space. First, different design thinking stimulates the information source and is obtained by analyzing the designers’ thinking process when designing and mining the dynamic mechanism behind it. Based on the nonlinear cognitive cobweb process proposed by Francisco and a natural cobweb structure, the product image cognitive cobweb model (PICCM) is constructed. Then, natural cobweb predation behavior is simulated using a stimulus information source to impact the PICCM. This process uses genetic algorithms to obtain numerous offspring forms, and the PICCM’s mechanical properties are the energy loss parameters in the impact information. Furthermore, feasible solutions are selected from intelligent design sketches by the product artificial form evaluation system based on designers’ cognition, and a new product image cognitive cobweb system is reconstructed. Finally, a case study demonstrates the efficiency and feasibility of the proposed approach.