bluuebunny/crossref_metadata_2025 huggingface dataset:
Trends and projections of caesarean section rates: global and regional estimates
Authors: Betran Ana Pilar , Ye Jiangfeng , Moller Ann-Beth , Souza João Paulo , Zhang Jun
Published: June 2021

Background

The caesarean section (CS) rate continues to increase across high-income, middle-income and low-income countries. We present current global and regional CS rates, trends since 1990 and projections for 2030.

Methods

We obtained nationally representative data on the CS rate from countries worldwide from 1990 to 2018. We used routine health information systems reports and population-based household surveys. Using the latest available data, we calculated current regional and subregional weighted averages. We estimated trends by a piecewise analysis of CS rates at the national, regional and global levels from 1990 to 2018. We projected the CS rate and the number of CS expected in 2030 using autoregressive integrated moving-average models.

Results

Latest available data (2010–2018) from 154 countries covering 94.5% of world live births shows that 21.1% of women gave birth by caesarean worldwide, averages ranging from 5% in sub-Saharan Africa to 42.8% in Latin America and the Caribbean. CS has risen in all regions since 1990. Subregions with the greatest increases were Eastern Asia, Western Asia and Northern Africa (44.9, 34.7 and 31.5 percentage point increase, respectively) while sub-Saharan Africa and Northern America (3.6 and 9.5 percentage point increase, respectively) had the lowest rise. Projections showed that by 2030, 28.5% of women worldwide will give birth by CS (38 million caesareans of which 33.5 million in LMIC annually) ranging from 7.1% in sub-Saharan Africa to 63.4% in Eastern Asia .

Conclusion

The use of CS has steadily increased worldwide and will continue increasing over the current decade where both unmet need and overuse are expected to coexist. In the absence of global effective interventions to revert the trend, Southern Asia and sub-Saharan Africa will face a complex scenario with morbidity and mortality associated with the unmet need, the unsafe provision of CS and with the concomitant overuse of the surgical procedure which drains resources and adds avoidable morbidity and mortality. If the Sustainable Development Goals are to be achieved, comprehensively addressing the CS issue is a global priority.
Diet and Exercise for FRAILty (DEFRAIL): protocol for a study to examine the effect of a novel community-based group exercise and nutritional intervention, designed to reverse frailty in older adults
Authors: Bambrick Pádraig , Phelan Niamh , Grant Emma , Byrne Thomas , Harrison Michael , Mulcahy Ríona , Cooke John
Published: June 2021

Introduction

Frailty refers to a multifaceted age-related loss of physiological reserve. Aside from the immediate challenges it presents, it is also associated with various adverse health outcomes. Given our ageing population, the healthcare and societal costs resulting from frailty present a significant and growing public health challenge. Rapidly accumulating evidence suggests that resistance exercise combined with protein supplementation can reverse frailty in older adults. However, translation of these findings into practice has proven difficult, due to either a lack of clarity regarding the interventions used or the use of interventions not suitable for widespread implementation. There remains an absence of evidence-based programmes suitable for delivery to frail older adults in the community.

Methods and analysis

This paper outlines the protocol for a study to examine the effect of a novel programme of exercise and protein supplementation. This intervention has been developed by an expert consensus group, specifically for delivery to frail older adults in a group setting in the community. The study will take the form of a within-subjects non-randomised trial. Participants will be assessed at baseline, then following an 8-week period of regular activity, then following the 8-week intervention. Frailty (according to the Fried Frailty criteria) will be the primary outcome measure, along with a range of secondary outcome measures (including physical performance measures, body mass composition, psychosocial assessments and frailty-related biomarkers). If shown to be feasible to implement and effective at reversing frailty, the Diet and Exercise for FRAILty (DEFRAIL) intervention may facilitate more widespread participation in resistance exercise for frail older adults.

Ethics and dissemination

This study received ethical approval from the Research Ethics committees of both the Health Service Executive South-Eastern Area and Waterford Institute of Technology. Its findings will be disseminated through journal publications, conference presentations and other forms of public engagement.

Trial registration number

ISRCTN46458028; Pre-results.
Areca nut consumption with and without tobacco among the adult population: a nationally representative study from India
Authors: Singh Prashant Kumar , Yadav Amit , Singh Lucky , Mazumdar Sumit , Sinha Dhirendra N , Straif Kurt , Singh Shalini
Published: June 2021

Objective

Areca nut is one of the most widely consumed substances globally, after nicotine, ethanol and caffeine and classified as carcinogenic to humans. This study examines the disparity and determinants of areca nut consumption with and without tobacco in India.

Design

Nationally representative cross-sectional study.

Participants

We used the nationally representative Global Adult Tobacco Survey 2016–2017. The analytical sample size was 74 037 individual’s aged 15 years and above with a response rate of 92.9%.

Measures

Current consumption of areca nut without tobacco and with tobacco.

Method

We examined determinants of areca nut consumption (without tobacco and with tobacco) using multinomial logistic regression, accounting for the survey design.

Results

About 23.9% (95% CI 23.1 to 24.8) of the adult population consume areca nut, that is, approximately 223.79 million people in India; majority of users (14.2%–95% CI 13.5 to 14.9) consumed areca nut with tobacco. When compared with women, men were more likely to consume areca nut (with tobacco relative risk (RR)=2.02; 95% CI 1.85 to 2.21 and without tobacco RR=1.13; 95% CI 1.07 to 1.20). Age, marital status, education, occupation, caste, religion and region were significantly associated with areca nut consumption. However, the direction and magnitude of association differ with respect to the areca nut consumption with and without tobacco.

Conclusion

The ongoing tobacco control efforts would not address the majority of areca nut users until greater attention to areca nut consumption with and without tobacco is reflected in health policies in India.
Home-based virtual reality for chronic pain: protocol for an NIH-supported randomised-controlled trial
Authors: Birckhead Brandon , Eberlein Sam , Alvarez Genie , Gale Rebecca , Dupuy Taylor , Makaroff Katherine , Fuller Garth , Liu Xiaoyu , Yu Kyung-Sang , Black J T , Ishimori Mariko , Venuturupalli Swamy , Tu Joseph , Norris Tom , Tighiouart Mourad , Ross Lindsey , McKelvey Karma , Vrahas Mark , Danovitch Itai , Spiegel Brennan
Published: June 2021

Introduction

Chronic pain is highly prevalent and associated with a large burden of illness; there is a pressing need for safe, home-based, non-pharmacological, interventions. Virtual reality (VR) is a digital therapeutic known to be effective for acute pain, but its role in chronic pain is not yet fully elucidated. Here we present a protocol for the National Institute of Health (NIH) Back Pain Consortium (BACPAC) VR trial that evaluates the effectiveness of three forms of VR for patients with chronic lower back pain (cLBP), a highly prevalent form of chronic pain.

Methods and analysis

The NIH BACPAC VR trial will randomise 360 patients with cLBP into one of three arms, each administered through a head-mounted display: 1)skills-based VR, a program incorporating principles of cognitive behavioural therapy, mindful meditation and physiological biofeedback therapy using embedded biometric sensors; 2)distraction-based VR,a program using 360-degree immersive videos designed to distract users from pain; and 3)sham VR, a non-immersive program using two-dimensional videos within a VR headset. Research participants will be monitored for 12 weeks using a combination of patient-reported outcomes administered via REDCap (Research Electronic Data Capture), wearable sensor data collected via Fitbit Charge 4 and electronic health record data. The primary outcome will be the NIH Patient-Reported Outcomes Measurement Information System (PROMIS) Pain Interference scale. Secondary outcomes will include PROMIS Anxiety, PROMIS Sleep Disturbance, opioid prescription data and Pain Catastrophizing Scale Short Form. A subgroup analysis will explore patient level predictors for VR efficacy.

Ethics and dissemination

Ethics approval was obtained from the Institutional Review Board of Cedars-Sinai Health System in April 2020. The results will be disseminated in a peer-reviewed journal.

Trial registration number

NCT04409353.
Prognostic factors for chronic post-surgical pain after lung or pleural surgery: a protocol for a systematic review and meta-analysis
Authors: Clephas Pascal Richard David , Hoeks Sanne Elisabeth , Trivella Marialena , Guay Christian S , Singh Preet Mohinder , Klimek Markus , Heesen Michael
Published: June 2021

Introduction

Chronic post-surgical pain (CPSP) after lung or pleural surgery is a common complication and associated with a decrease in quality of life, long-term use of pain medication and substantial economic costs. An abundant number of primary prognostic factor studies are published each year, but findings are often inconsistent, methods heterogeneous and the methodological quality questionable. Systematic reviews and meta-analyses are therefore needed to summarise the evidence.

Methods and analysis

The reporting of this protocol adheres to the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) checklist. We will include retrospective and prospective studies with a follow-up of at least 3 months reporting patient-related factors and surgery-related factors for any adult population. Randomised controlled trials will be included if they report on prognostic factors for CPSP after lung or pleural surgery. We will exclude case series, case reports, literature reviews, studies that do not report results for lung or pleural surgery separately and studies that modified the treatment or prognostic factor based on pain during the observation period. MEDLINE, Scopus, Web of Science, Embase, Cochrane, CINAHL, Google Scholar and relevant literature reviews will be searched. Independent pairs of two reviewers will assess studies in two stages based on the PICOTS criteria. We will use the Quality in Prognostic Studies tool for the quality assessment and the CHARMS-PF checklist for the data extraction of the included studies. The analyses will all be conducted separately for each identified prognostic factor. We will analyse adjusted and unadjusted estimated measures separately. When possible, evidence will be summarised with a meta-analysis and otherwise narratively. We will quantify heterogeneity by calculating the Q and I2statistics. The heterogeneity will be further explored with meta-regression and subgroup analyses based on clinical knowledge. The quality of the evidence obtained will be evaluated according to the Grades of Recommendation Assessment, Development and Evaluation guideline 28.

Ethics and dissemination

Ethical approval will not be necessary, as all data are already in the public domain. Results will be published in a peer-reviewed scientific journal.

PROSPERO registration number

CRD42021227888.
Patient-reported outcome measures in ophthalmology: too difficult to read?
Authors: Taylor Deanna J , Jones Lee , Edwards Laura , Crabb David P
Published: June 2021

Objective

Patient-reported outcome measures (PROMs) are commonly used in clinical trials and research. Yet, in order to be effective, a PROM needs to be understandable to respondents. The aim of this cross-sectional analysis was to assess reading level of PROMs validated for use in common eye conditions.

Methods and analysis

Readability measures determine the level of education a person is expected to have attained to be able to read a passage of text; this was calculated using the Flesch-Kincaid Grade Level, FORCAST and Gunning-Fog tests within readability calculations software package Oleander Readability Studio 2012.1. Forty PROMs, previously validated for use in at least one of age-related macular degeneration, glaucoma and/or diabetic retinopathy, were identified for inclusion via a systematic literature search. The American Medical Association (AMA) and National Institutes of Health (NIH) recommend patient materials should not exceed a sixth-grade reading level. Number of PROMs exceeding this level was calculated.

Results

Median (IQR) readability scores were 7.9 (5.4–10.5), 9.9 (8.9–10.7) and 8.4 (6.9–11.1) for Flesch-Kincaid Grade Level, FORCAST and Gunning-Fog test, respectively. Depending on metric used, this meant 61% (95% CI 45% to 76%), 100% (95% CI 91% to 100%) and 80% (95% CI 65% to 91%) exceeded the recommended threshold.

Conclusion

Most PROMs commonly used in ophthalmology require a higher reading level than that recommended by the AMA and NIH and likely contain questions that are too difficult for many patients to read. Greater care is needed in designing PROMs appropriate for the literacy level of a population.
Incorporating parent, former patient and clinician perspectives in the design of a national UK double-cluster, randomised controlled trial addressing uncertainties in preterm nutrition
Authors: Lammons William , Moss Becky , Battersby Cheryl , Cornelius Victoria , Babalis Daphne , Modi Neena
Published: June 2021

Background

Comparative effectiveness randomised controlled trials are powerful tools to resolve uncertainties in existing treatments and care processes. We sought parent and patient perspectives on the design of a planned national, double-cluster randomised controlled trial (COLLABORATE) to resolve two longstanding uncertainties in preterm nutrition.

Methods

We used qualitative focus groups and interviews with parents, former patients and clinicians. We followed the Consolidated Criteria for Reporting Qualitative Research checklist and conducted framework analysis, a specific methodology within thematic analysis.

Results

We identified support for the trial’s methodology and vision, and elicited themes illustrating parents’ emotional needs in relation to clinical research. These were: relieving the pressure on mothers to breastfeed; opt-out consent as reducing parent stress; the desire for research to be a partnership between clinicians, parents and researchers; the value of presenting trial information in a collaborative tone; and in a format that allows assimilation by parents at their own pace. We identified anxiety and cognitive dissonance among some clinicians in which they recognised the uncertainties that justify the trial but felt unable to participate because of their strongly held views.

Conclusions

The early involvement of parents and former patients identified the centrality of parents’ emotional needs in the design of comparative effectiveness research. These insights have been incorporated into trial enrolment processes and information provided to participants. Specific outputs were a two-sided leaflet providing very brief as well as more detailed information, and use of language that parents perceive as inclusive and participatory. Further work is warranted to support clinicians to address personal biases that inhibit trial participation.
Is the international regulation of medical complicity with torture largely window dressing? The case of Israel and the lessons of a 12-year medical ethical appeal
Authors: Summerfield Derek
Published: June 2021

This is the account of an ongoing appeal initiated in 2009 by 725 doctors from 43 countries concerning medical complicity with torture in Israel. It has been underpinned by a voluminous and still accumulating evidence base from reputable international and regional human rights organisations, quoted below, and has spanned the terms of office of four World Medical Association (WMA) presidencies and two UN special rapporteurs on torture. This campaign has been a litmus test of whether international medical codes regarding doctors and torture actually matter, and are applied rigorously and even-handededly, particularly when compelling evidence incriminates a WMA member association. Our findings in the case of Israel suggest that this is not true, and that impunity largely operates. The WMA seems in partisan violation of its mandate to be the official international watchdog on the ethical behaviour of doctors. And as the IMA case demonstrates, by their inaction national medical associations or other regulatory bodies appear to function at base as buttresses and shields of the state.
Smokers’ awareness of filter ventilation, and how they believe it affects them: findings from the ITC Four Country Survey
Authors: King Bill , Borland Ron , Le Grande Michael , O'Connor Richard , Fong Geoffrey , McNeill Ann , Hatsukami Dorothy , Cummings Michael
Published: June 2021

Background

Filter ventilation creates sensations of ‘lightness’ or ‘smoothness’ and is also highly effective for controlling machine-tested yields of tar, nicotine and carbon monoxide. Nearly all factory-made cigarettes (FMC) now have filter ventilation in countries such as Australia, Canada, the UK and the USA. Research conducted before ‘light’ and ‘mild’ labelling was banned found low smoker awareness of filter ventilation and its effects. This study explores current levels of awareness of filter ventilation and current understanding of its effects in these four countries.

Methods

We used data from the 2018 wave of the ITC Four Country Smoking and Vaping Survey with samples from USA, England, Canada and Australia. Analyses were conducted initially on a weighted sample of 11 844, and subsequently on 7541 daily FMC smokers.

Findings

Only 40.3% of all respondents reported being aware of filter ventilation. Among daily FMC smokers, only 9.4% believed their cigarettes had filter ventilation. Believing that their usual cigarettes are smoother was positively associated with believing they are also less harmful. Both these beliefs independently predict believing their cigarettes are ventilated (smoother OR=1.97 (95% CI 1.50 to 2.59) and less harmful OR=2.41 (95% CI 1.66 to 3.49) in relation to those believing each characteristic is average.

Interpretation

Awareness of filter ventilation is currently low, despite decades of public ‘education efforts around the misleading nature of ‘light’ and ‘mild” descriptors. Few smokers realise that their cigarettes almost certainly are vented. Smokers who believed their cigarettes have filter ventilation were more likely to believe they were both smoother and less harmful. Awareness of the technology appears to be insufficient to prevent smokers being deceived by it. Filter ventilation is inherently misleading to smokers and it is time to ban it.
‘Ice’ flavoured e-cigarette use among young adults
Authors: Leventhal Adam , Dai Hongying , Barrington-Trimis Jessica , Sussman Steve
Published: June 2021

Background

‘Ice’ e-cigarette flavours—marketed as a combination of fruity/sweet and cooling flavours (eg, ‘blueberry ice’ or ‘melon ice’)—recently entered the US market. The prevalence and correlates of ice flavoured e-cigarette use in young adults are unknown.

Methods

This cross-sectional study of a Los Angeles, California, USA, cohort analysed data from the past 30-day e-cigarette (current) users (n=344; M (SD)=21.2 (0.4) years old) who completed web-based surveys from May–August 2020. The exposure variable was self-reported e-cigarette flavour used most often in the past month (menthol/mint, fruit/sweet or ice). Outcomes included self-reported combustible tobacco use, vaping dependence symptoms, frequency of use and device type used.

Results

Among current e-cigarette users, 48.8% reported using ice flavours most often, 33.7% predominately used fruit/sweet and 17.4% used menthol/mint. Using primarily ice-flavour was associated with reporting more past-30-day vaping days (vs menthol/mint: b=4.4, 95% CI (1 to 7.7); vs fruit/sweet: b=3.6, 95% CI (0.8 to 6.4)) and more episodes per vaping day versus fruit/sweet users (b=2.4, 95% CI (0.5 to 4.3)). Ice-flavour users were less likely than menthol/mint users to use JUUL/cartridge-based rechargeable (OR=0.1, 95% CI (0.03 to 0.45)) and more likely than sweet/fruit users to use disposable non-cartridge (OR=3.9, 95% CI (2.1 to 7.4)) devices than refillable/rechargeable tank/pen or other devices. Ice users had greater odds of past 30-day combustible tobacco use versus menthol/mint users (OR=2.7, 95% CI (1.3 to 5.7)) and vaping dependence symptoms than versus sweet/fruit users (OR=2.6, 95% CI (1.5 to 4.4)).

Conclusion

Young adult use of ice flavoured e-cigarettes may be common and positively associated with combustible tobacco use, nicotine vaping frequency and dependence and use of disposable e-cigarette devices. Further study of the prevalence, determinants and health effects of ice flavoured e-cigarette use is warranted.
Retrospective study on rib fractures: smoking and alcohol matter for mortality and complications
Authors: Gongola AlleaBelle , Bradshaw Jace C , Jin Jing , Jensen Hanna K , Bhavaraju Avi , Margolick Joseph , Sexton Kevin W , Robertson Ronald , Kalkwarf Kyle J
Published: June 2021

Background

Rib fractures and substance use are both common in trauma patients, but there is little data on how smoking and alcohol use may be associated with outcomes in these patients. We assessed the association between smoking or alcohol use disorder (AUD) and outcomes in patients with rib fractures.

Methods

We used institutional databases to conduct a retrospective review of patients with rib fractures at the only American College of Surgeons-verified adult level 1 trauma center in a rural state between 2015 and 2019. The key exposure variables were smoking and AUD. The key outcome variables were mortality and pulmonary complications (pneumonia, adult respiratory distress syndrome, and pneumothorax). We used multivariable regression for analysis and directed acyclic graphs to identify variables for adjustment.

Results

We identified 1880 eligible patients with rib fractures, including 693 (37%) who were smokers and 204 (11%) who had AUD. Compared with non-smokers, smokers were younger, more often male, and had lower mortality rates. Regression showed that smokers had a lower likelihood of mortality (OR 0.48; 95% CI 0.27 to 0.87; p=014). Likelihood of pneumonia, ARDS, and pneumothorax was not different between smokers and non-smokers. Compared with patients without AUD, patients with AUD were older, more often male, and had higher likelihood of pneumonia and lower likelihood of pneumothorax. Regression showed that patients with AUD had higher likelihood of pneumonia (OR 1.82; 95% CI 1.24 to 2.68; p=0.002) and lower likelihood of pneumothorax (OR 0.51; 95% CI 0.33 to 0.75; p=0.002).

Discussion

In trauma patients with rib fractures treated at a level 1 trauma center over 5 years, smoking was associated with decreased risk of mortality. These findings have implications for risk stratification and clinical decision-making for patients with rib fractures.

Level of evidence

III
Intraspecific variations of the cytoplasmic male sterility genes orf108 and orf117 in Brassica maurorum and Moricandia arvensis, and the specificity of the mRNA processing
Authors: Yamagishi Hiroshi , Hashimoto Ayako , Fukunaga Asumi , Bang Sang Woo , Terachi Toru
Published: June 2021

The mitochondrial gene orf108, which is co-transcribed with atp1 and causes cytoplasmic male sterility in Brassica crops, is widely distributed across wild species and genera of Brassicaceae. However, to date, intraspecific variations in the presence of orf108 have not yet been studied, and the mechanisms underlying the wide distribution of the gene remain unclear. We analyzed the presence and sequence variations of orf108 in two wild species, Brassica maurorum and Moricandia arvensis. After polymerase chain reaction amplification of the 5′ region of atp1 and the coding sequence of orf108, we determined the DNA sequences. Brassica maurorum and M. arvensis showed variations in the presence of orf108 or orf117 (orf108V117) both between and within accessions and were not fixed to the mitochondrial type with the male sterile genes. Sequencing of the amplicons showed that B. maurorum had orf108V117 instead of orf108. Sequencing also indicated mitochondrial heteroplasmy in the two species; in particular, in B. maurorum, one plant possessed both orf108 and orf108V117 sequences. These results suggest that substoichiometric shifting of mitochondrial genomes leads to the acquisition or loss of orf108. Furthermore, fertility restorer genes of the two species were involved in the processing of the mRNA of male sterility genes at different sites.
Low-energy excitations and $$\gamma $$-decay branchings in $$^{124}$$Sn via (p,p’$$\gamma $$) at $$E_p={15}\,\,\hbox {MeV}$$
Authors: Färber Michelle , Weinert Michael , Müscher Miriam , Spieker Mark , Wilhelmy Julius , Zilges Andreas
Published: June 2021

The dipole response of the proton-magic nucleus$${}^{124}\hbox {Sn}$$124Snwas previously investigated with electromagnetic and hadronic probes. Different responses were observed revealing the so-called isospin splitting of the Pygmy Dipole Resonance (PDR). Here we present the results of a new study of$${}^{124}\hbox {Sn}$$124Snusing inelastic proton scattering at low energies to test an additional probe possibly exciting states of the PDR. The response to the new probe as well as the$$\gamma $$γ-decay behavior of excited states were studied. The$${}^{124}\hbox {Sn}$$124Sn(p,p’$$\gamma $$γ) experiment was performed at$$E_p = {15}\,\,\hbox {MeV}$$Ep=15MeVusing the combined spectroscopy setup SONIC@HORUS at the Tandem accelerator of the University of Cologne. Proton-$$\gamma $$γcoincidences were recorded, enabling a state-to-state analysis due to the excellent energy resolution for both particles and$$\gamma $$γrays.$$ J=1 $$J=1states in the PDR region were populated in the present inelastic proton scattering experiment. Many$$\gamma $$γ-decay branching ratios could be determined.
Modelling of expected B, C, N and O Lyman-α line intensities emitted from W7-X plasmas and measured by means of the W7-X light impurity monitor system
Authors: Fornal Tomasz , Kubkowska Monika , Książek Ireneusz , Stańczak Dominik , Jabłoński Sławomir , Burhenn Rainer ,   W7-X. team
Published: June 2021

The “C/O Monitor” for Wendelstein 7-X (W7-X) is a dedicated light impurity XUV spectrometer intended to measure Lyman-α transitions of hydrogen-like ions of four low-Z impurities—boron (4.9 nm), carbon (3.4 nm), nitrogen (2.5 nm) and oxygen (1.9 nm). Since the discussed diagnostic will deliver continuous information about the line intensities, it is crucial to understand the origin of the obtained signals with respect to the experimental plasma conditions (electron temperature and density). This, however, might be difficult because of the broad acceptance angle of the spectrometer and irregular shape of the plasma edge or SOL where the radiation is expected to mostly come from, depending on the plasma temperature. For that reason, numerous analyses assuming various ranges of electron density and temperature profiles of the W7-X plasmas have been performed (assuming corona equilibrium and neglecting impurity transport processes). The aim of this work is to estimate the expected radiant flux and determine the sensitivity of the system on impurity-level changes. It will allow to improve understanding between measured signal and impurity concentration.
Forced convection heat transfer of Ag–MgO/water micropolar hybrid nanofluid inside a stairway channel
Authors: Heidari Hanif , Mohebbi Rasul , Kazemi Amir
Published: June 2021

In this paper, the forced convection heat transfer of Ag–MgO/water hybrid micropolar nanofluid in a channel is studied numerically which the top wall of channel is smooth and bottom of it is in stairway form. The lattice Boltzmann method (LBM) is used for solving the fluid flow and heat transfer equations. The effects of Reynolds numbers ([Formula: see text]–400), volume fraction of nanofluid ([Formula: see text], 0.01 and 0.02) and stairway aspect ratio ([Formula: see text], 0.2 and 0.3) on the velocity, temperature and local and average Nusselt number profiles are investigated. The results show that by incrementing the Reynolds number and solid volume fraction and decreasing the [Formula: see text]/[Formula: see text] simultaneously, the average Nusselt number increases.
Evolutionary Game Models of Cooperative Strategies in Blockchain-Enabled Container Transport Chains
Authors: Hu Zhi-Hua , Dong Ya-Jing
Published: June 2021

This paper describes the interaction between major and auxiliary container transport carriers (MCs and ACs) by using evolutionary game theory models, enabling them to cooperate and share information under sufficient penalties and incentives. The MCs are generally logistics service integrators, mega shipping companies, and port authorities, which affect the regulations and technology innovation much, while the ACs are rest carriers and logistics service providers. Evolutionary games are used to study the cooperative behavior between MCs and ACs in the shipping industry. As indicated by analytical studies, the cooperation between MCs and ACs will be invalid without introducing blockchain technology for adequate supervision. In peak season, an evolutionary equilibrium incurs between MCs and ACs under cooperation or non-cooperation behavior strategies. However, in off-seasons, the evolutionary equilibrium is unique in which both parties choose not to cooperate. When introducing blockchain technology for supervision, the carriers will cooperate in peak and off-seasons. Besides, through a simulation analysis of the established models, the results show that the introduction of blockchain technology can enable carriers to form cooperative alliances, resolve inefficient operations, and achieve a long-term stable equilibrium strategy. We can also apply the results for reference to the regional shipping industry.
Quantum gravity corrections to tunneling of spin-1/2 fermions from Kerr–Newman Black Hole
Authors: Singh Aheibam Keshwarjit , Meitei Irom Ablu , Singh Telem Ibungochouba , Singh Kangujam Yugindro
Published: June 2021

In this paper, we solve the Dirac Equation in curved space–time, modified by the generalized uncertainty principle, in the presence of an electromagnetic field. Using this, we study the tunneling of [Formula: see text]-spin fermions from Kerr–Newman black hole. Corrections to the Hawking temperature and entropy of the black hole due to quantum gravity effects are also discussed.
New Grounded and Floating Memristor-Less Meminductor Emulators Using VDTA and CDBA
Authors: Yadav Nisha , Rai Shireesh Kumar , Pandey Rishikesh
Published: June 2021

In this paper, new memristor-less meminductor emulators have been proposed using voltage differencing transconductance amplifier (VDTA), current differencing buffered amplifier (CDBA) and a grounded capacitor. The proposed decremental/incremental meminductor emulators have been realized in both grounded and floating types of configurations. In the proposed meminductor emulators, analog multiplier, memristor and passive resistors are not used which result in simpler configurations. The pinched hysteresis loops are maintained up to 2[Formula: see text]MHz for both decremental and incremental configurations of meminductor emulators. The behaviors of decremental and incremental meminductor emulators have been analyzed after applying input pulses. The obtained results verify the performances as decremental and incremental meminductor emulators. The simulation results have been obtained using Mentor Graphics Eldo simulation tool with 180[Formula: see text]nm CMOS technology parameters. To verify the performances of the proposed meminductor emulators, adaptive learning circuit and chaotic oscillator have been designed. The performances of the proposed meminductor emulators are compared with other meminductor emulators reported in the literature.
Constant-roll inflation driven by q-de Sitter
Authors: Bahari K. , Setare M. R.
Published: June 2021

We have studied constant-roll inflation using the q-de Sitter scale factor. Both the cold and warm inflation have been considered, and the scalar potential and inflaton field have been determined. Also tensor to scalar ratio and the spectral index are obtained. In the cold inflation case, the perturbations have been investigated using Mukhanov–Sasaki equation, and the results determined for the spectral index and tensor to scalar ration are consistent with observations. In the warm inflation two cases of constant damping ([Formula: see text]) and the field dependent damping ([Formula: see text]) have been studied. In both cases the power spectrum and the tensor to scalar ratio are determined as a function of the inflaton field. It has been shown that in both cases the spectral index is independent of the inflaton field. In the case of constant damping the obtained value for the spectral index is inconsistent with observations but for the case of field dependent damping the parameter [Formula: see text] can be chosen such that the value obtained for all the physical quantities including the spectral index be consistent with present cosmological observations.
Gross features of the spectrum of the 36Ar nucleus
Authors: Riczu Gábor , Cseh József
Published: June 2021

Samples of the spectrum of the [Formula: see text]Ar nucleus are known in different energy windows. In addition to the ground-state (GS) region, the superdeformed (SD) state is observed, too, and there is a good candidate for the hyperdeformed (HD) one, as well. They are populated in different reactions. We intend to describe the gross features of the spectra of different energies, deformations and reactions in a unified way. We apply the multiconfigurational dynamical symmetry (MUSY). The SU(3) quantum numbers of the shape isomers from previous studies pave the way for this description. The MUSY reproduces the gross features of the spectra to a reasonable approximation. The energy spectrum of the three valleys (GS, SD, HD) indicates that the multiconfigurational symmetry is valid to a good approximation, and different cluster configurations coexist in the shape isomers.
RECENT RESEARCH PROGRESS IN DEEP HOLE DRILLING PROCESS: A REVIEW
Authors: CHANDAR J. BHARANI , NAGARAJAN L. , KUMAR M. SIVA
Published: June 2021

The requirement of deep hole drilling has tremendously increased in recent years and it extensively found applications in automobile fuel injectors, biomedical implants, aerospace landing gears, etc. These deep holes are fabricated by conventional and unconventional methods with a high aspect ratio ([Formula: see text]/[Formula: see text]) and tight tolerance. This paper is an attempt to review the research work carried out by researchers in recent years about deep hole drilling on various materials using conventional methods like Gun Drilling (GD), Boring and Trepanning Association (BTA) drilling, and Single Lip Drilling (SLD) and unconventional methods such as Laser Beam Machining (LBM), Electro-Chemical Machining (ECM), Electro Discharge Machining (EDM), and Abrasive Water Jet Machining (AWJM). The review includes the impact analysis of process parameters namely water jet pressure, stand-off distance, and abrasive mass flow rate on the responses of AWJM. The current gaps and the upcoming research directions in the deep hole drilling process are detailed.
Energy-Harvesting Adaptive Vibration Damping in High-Speed Train Suspension Using Electromagnetic Dampers
Authors: Cai Qinlin , Hua Yingyu , Zhu Songye
Published: June 2021

Electromagnetic damper cum energy harvester (EMDEH) is an emerging dual-function device that enables simultaneous energy harvesting and vibration control. This study presents a novel energy-harvesting adaptive vibration control application of EMDEH on the basis of the past EMDEH development in passive control. The proposed EMDEH comprises an electromagnetic damper connected to a specifically designed energy harvesting circuit (EHC), wherein the EHC is a buck–boost converter with a microcontroller unit (MCU) and a bridge rectifier. The effectiveness of the energy-harvesting adaptive vibration damping is validated numerically through a high-speed train (HST) model running at different speeds. MCU-controlled adaptive duty cycle adjustment in the EHC enables the EMDEHs to adaptively offer the optimal damping coefficients that are highly dependent on train speeds. In the meantime, the harvested power can be stored in rechargeable batteries by the EHC. Numerical results project the average output power ranging from 40.5[Formula: see text]W to 589.8[Formula: see text]W from four EMDEHs at train speed of 100–340[Formula: see text]km/h, with a maximum output power efficiency of approximately 35%. In comparison to energy-harvesting passive vibration control and a pure viscous damper, the proposed energy-harvesting adaptive control strategy can improve vibration reductions by approximately 40% and 27%, respectively, at a speed of 340[Formula: see text]km/h. These numerical results clearly demonstrate the benefit and prospect of the proposed energy-harvesting adaptive vibration control in HST suspensions.
Holographic cosmology with two coupled fluids in the presence of viscosity
Authors: Brevik I. , Timoshkin A. V.
Published: June 2021

We explore the cosmological models of the late-time universe based on the holographic principle, taking into account the properties of the viscosity of the dark fluid. We use the mathematical formalism of generalized infrared cutoff holographic dark energy, as presented by Nojiri and Odintsov [Covariant generalized holographic dark energy and accelerating universe, Eur. Phys. J. C 77 (2017) 528]. We consider the Little Rip, the Pseudo Rip, and a bounce exponential model, with two interacting fluids, namely dark energy and dark matter in a spatially-flat Friedmann–Robertson–Walker universe. Within these models, analytical expressions are obtained for infrared cutoffs in terms of the particle horizons. The law of conservation of energy is presented, from a holographic point of view.
Improving the photodynamic therapy of pyropheophorbide a through the combination of hypoxia-sensitive molecule and infrared light-excited d-TiO2−X nanoparticles
Authors: Yang Chen , Wang Xingchao , Ma Wei , Wang Zhiqiang , Tan Guanghui , Fang Wen , Jin Yingxue
Published: June 2021

Photodynamic therapy (PDT) involving the generation of cytotoxic reactive oxygen species under light in the presence of sufficient oxygen has been widely used in diagnosing and treating cancer. However, the ubiquitous hypoxia in many solid tumors due to their abnormal proliferation and vascularization has greatly compromised the therapeutic effect. We have designed and prepared a tumor therapeutic nanoplatform for improving PDT based on defective TiO[Formula: see text] (d-TiO[Formula: see text] with the consideration that the continuous PDT would cause hypoxic tumor microenvironment (HTM) in which many hypoxia-sensitive drugs might be activated to exert the antitumor activities. The inorganic d-TiO[Formula: see text] nanoparticles (NPs) were firstly prepared and then modified by APTES to obtain the mesoporous d-TiO[Formula: see text]@SiO2NPs. The organic photosensitizer pyropheophorbide-a (PPa) and hypoxic-sensitive agent 6-aminoflavone (AF) were then adsorbed in the mesoporous SiO2, followed by further hydrophilic PEGylation to improve the biocompatibility. Defective d-TiO[Formula: see text] and the PPa could simultaneously consume oxygen after light excitation, while the resulted HTM was utilized to activate the hypoxic-sensitive agent 6-aminoflavone (AF) to trigger anti-cancer effect. The prepared d-TiO[Formula: see text]@SiO2/PPa/AF@PEG NPs were stable in normal physiological environment, and could continuously release PPa and AF under slightly acidic conditions. The in vitro experiments against cancer cells suggested that the combination of PPa and AF displayed significantly enhanced antitumor activities than that of monotherapy. Therefore, this research offered a potential application for 6-aminoflavone in PDT-induced hypoxia to improve the antitumor effects.
Weighted average price management of sales under the given minimum volume of assets obligatory for realization
Authors: Svetlov Kirill V. , Vavilov Sergey A.
Published: June 2021

In this paper, we consider the construction of a sales management strategy for a highly liquid asset trading at the market. The proposed strategy goal is to maximize the weighted average price of sales. It is assumed that the market price follows a geometric Brownian motion process in which drift and volatility coefficients are random functions of time. The important feature of the given management is that the volumes of assets in the succession of buy and sell executed bargains are calculated exclusively on the basis of the observed market prices rather than on the model coefficient values. In contrast to the management proposed earlier in this study, obligatory realization of some minimum volume of assets on the given time period is demanded. Examples of real-world markets trade demonstrating the imposed constraints effect on the weighted average price values obtained within the constructed management are given.
The Ends Dictate the Means: Promoter Switching in Herpesvirus Gene Expression
Authors: Hale Andrew E. , Moorman Nathaniel J.
Published: June 2021

Herpesvirus gene expression is dynamic and complex, with distinct complements of viral genes expressed at specific times in different infection contexts. These complex patterns of viral gene expression arise in part from the integration of multiple cellular and viral signals that affect the transcription of viral genes. The use of alternative promoters provides an increased level of control, allowing different promoters to direct the transcription of the same gene in response to distinct temporal and contextual cues. While once considered rare, herpesvirus alternative promoter usage was recently found to be far more pervasive and impactful than previously thought. Here we review several examples of promoter switching in herpesviruses and discuss the functional consequences on the transcriptional and post-transcriptional regulation of viral gene expression.
Improving the Sense of Gain of Graduate Students in Food Science
Authors: Wan Youling , Guo Zhiming
Published: June 2021

Improvement of the sense of gain as an internal driving force is the key factor to improve the training quality of graduate students in food science. Utilizing Jiangsu University graduate students majoring in food science as research samples, this study analyzed the present situation of the “sense of gain” demand. We analyzed the reasonable appeals of graduate students during their study based on fully respecting and advocating students’ right of speech, listened to their opinions and suggestions on higher education, analyzed the main contradictions, and further put forward a series of countermeasures. For improving the graduate students’ sense of gain during the period of study, it is necessary to improve the training quality from the following five aspects: constructing high-quality courses, cultivating people’s responsibilities, implementing “soft elimination” of training links, carrying out diversified extracurricular activities, and developing comprehensive quality. This research is significant in improving the training quality of food science graduate students.
Sugarcane Bagasse-Derived Activated Carbon- (AC-) Epoxy Vitrimer Biocomposite: Thermomechanical and Self-Healing Performance
Authors: Krishnakumar Balaji , Bose Debajyoti , Singh Manjeet , Sanka R. V. Siva Prasanna , Gurunadh Velidi V. S. S. , Singhal Shailey , Parthasarthy Vijay , Guadagno Liberata , Vijayan P Poornima , Thomas Sabu , Rana Sravendra
Published: June 2021

Vitrimeric materials have emerged as fascinating and sustainable materials owing to their malleability, reprocessability, and recyclability. Sustainable vitrimeric materials can be prepared by reinforcing polymeric matrix with bioderived fillers. In the current work, a sustainable vitrimer is prepared by incorporating biomass-derived activated carbon (AC) filler into the epoxy matrix to achieve enhanced thermal and mechanical properties. Thus, prepared biocomposite vitrimers demonstrate a lower-temperature self-healing (70°C for 5 min) via disulfide exchanges, compared to the pristine epoxy vitrimers (80°C for 5 min). Significantly, the self-healing performances have been studied extensively with the flexural studies; and changes in material healing efficiency have been demonstrated based on the observed changes in modulus.
Comparing and Analyzing Applications of Intelligent Techniques in Cyberattack Detection
Authors: Dixit Priyanka , Kohli Rashi , Acevedo-Duque Angel , Gonzalez-Diaz Romel Ramon , Jhaveri Rutvij H.
Published: June 2021

Now a day’s advancement in technology increases the use of automation, mobility, smart devices, and application over the Internet that can create serious problems for protection and the privacy of digital data and raised the global security issues. Therefore, the necessity of intelligent systems or techniques can prevent and protect the data over the network. Cyberattack is the most prominent problem of cybersecurity and now a challenging area of research for scientists and researchers. These attacks may destroy data, system, and resources and sometimes may damage the whole network. Previously numerous traditional techniques were used for the detection and mitigation of cyberattack, but the techniques are not efficient for new attacks. Today’s machine learning and metaheuristic techniques are popularly applied in different areas to achieve efficient computation and fast processing of complex data of the network. This paper is discussing the improvements and enhancement of security models, frameworks for the detection of cyberattacks, and prevention by using different machine learning and optimization techniques in the domain of cybersecurity. This paper is focused on the literature of different metaheuristic algorithms for optimal feature selection and machine learning techniques for the classification of attacks, and some of the prominent algorithms such as GA, evolutionary, PSO, machine learning, and others are discussed in detail. This study provides descriptions and tutorials that can be referred from various literature citations, references, or latest research papers. The techniques discussed are efficiently applied with high performance for detection, mitigation, and identification of cyberattacks and provide a security mechanism over the network. Hence, this survey presents the description of various existing intelligent techniques, attack datasets, different observations, and comparative studies in detail.