bluuebunny/crossref_metadata_2025 huggingface dataset:
Second opinion programmes in Germany: a mixed-methods study protocol
Authors: Bruch Dunja , May Susann , Prediger Barbara , Könsgen Nadja , Alexandrov Alexander , Mählmann Sonja , Voß Karl , Liersch Sebastian , Loh Jan-Christoph , Christensen Bernd , Franzen Achim , von Peter Sebastian , Pieper Dawid , Ronckers Cecile , Neugebauer Edmund
Published: February 2021

Introduction

Second opinion programmes aim to support the patients’ decision-making process and to avoid treatments that are unnecessary from a medical perspective. The German second opinion directive, introduced in December 2018, constitutes a new legal framework in statutory health insurance for seeking second opinions for elective procedures and so far includes tonsillectomy, tonsillotomy, hysterectomy and shoulder arthroscopy. The directive mandates physicians who recommend one of the above-mentioned surgeries to inform their patients of their legal right to visit a certified second opinion provider. Since second opinion programmes are a fairly recent phenomenon in Germany, no comprehensive data are yet available on the degree of implementation, users, potential barriers and their effectiveness. We aim to examine the characteristics and the use of second opinion programmes as well as the needs and wishes from the perspective of (potential) users in Germany, with focus on the decision-making process, the patient–physician relationship and the motivation to seek a second opinion, as well as the role of health literacy.

Methods and analysis

Six substudies will include the following stakeholders: (1 and 2) patients with one of the four surgery-indications covered by the directive, (3) patients who electively sought an online-based second opinion, (4) patients with oncological diseases, (5) the general population and (6) medical specialists. A mixed-methods approach will be used, including questionnaires, interviews and focus groups. The data will be evaluated using quantitative descriptive analysis and qualitative content analysis. The integration of the results will take place in the form of a triangulation protocol.

Ethics and dissemination

The study protocol was approved by the Ethics Committee of the Brandenburg Medical School. The findings will be published in peer-reviewed journals and presented at scientific conferences.
National, clinical cohort study of late effects among survivors of acute lymphoblastic leukaemia: the ALL-STAR study protocol
Authors: Andrés-Jensen Liv , Skipper Mette Tiedemann , Mielke Christensen Kristian , Hedegaard Johnsen Pia , Aagaard Myhr Katrine , Kaj Fridh Martin , Grell Kathrine , Pedersen A. M. L. , Leisgaard Mørck Rubak Sune , Ballegaard Martin , Hørlyck Arne , Beck Jensen Rikke , Lambine Trine-Lise , Gjerum Nielsen Kim , Tuckuviene Ruta , Skov Wehner Peder , Klug Albertsen Birgitte , Schmiegelow Kjeld , Frandsen Thomas Leth
Published: February 2021

Introduction

More than 90% of patients diagnosed with childhood acute lymphoblastic leukaemia (ALL) today will survive. However, half of the survivors are expected to experience therapy-related chronic or late occurring adverse effects, reducing quality of life. Insight into underlying risk trajectories is warranted. The aim of this study is to establish a Nordic, national childhood ALL survivor cohort, to be investigated for the total somatic and psychosocial treatment-related burden as well as associated risk factors, allowing subsequent linkage to nation-wide public health registers.

Methods and analysis

This population-based observational cohort study includes clinical follow-up of a retrospective childhood ALL survivor cohort (n=475), treated according to a common Nordic ALL protocol during 2008–2018 in Denmark. The study includes matched controls. Primary endpoints are the cumulative incidence and cumulative burden of 197 health conditions, assessed through self-report and proxy-report questionnaires, medical chart validation, and clinical examinations. Secondary endpoints include organ-specific outcome, including cardiovascular and pulmonary function, physical performance, neuropathy, metabolic disturbances, hepatic and pancreatic function, bone health, oral and dental health, kidney function, puberty and fertility, fatigue, and psychosocial outcome. Therapy exposure, acute toxicities, and host genome variants are explored as risk factors.

Ethics and dissemination

The study is approved by the Regional Ethics Committee for the Capital Region in Denmark (H-18035090/H-20006359) and by the Danish Data Protection Agency (VD-2018–519). Results will be published in peer-reviewed journals and are expected to guide interventions that will ameliorate the burden of therapy without compromising the chance of cure.
False-negative RT-PCR for COVID-19 and a diagnostic risk score: a retrospective cohort study among patients admitted to hospital
Authors: Gupta-Wright Ankur , Macleod Colin Kenneth , Barrett Jessica , Filson Sarah Ann , Corrah Tumena , Parris Victoria , Sandhu Gurjinder , Harris Miriam , Tennant Rachel , Vaid Nidhi , Takata Junko , Duraisingham Sai , Gandy Nemi , Chana Harmeet , Whittington Ashley , McGregor Alastair , Papineni Padmasayee
Published: February 2021

Objective

To describe the characteristics and outcomes of patients with a clinical diagnosis of COVID-19 and false-negative SARS-CoV-2 reverse transcription-PCR (RT-PCR), and develop and internally validate a diagnostic risk score to predict risk of COVID-19 (including RT-PCR-negative COVID-19) among medical admissions.

Design

Retrospective cohort study.

Setting

Two hospitals within an acute NHS Trust in London, UK.

Participants

All patients admitted to medical wards between 2 March and 3 May 2020.

Outcomes

Main outcomes were diagnosis of COVID-19, SARS-CoV-2 RT-PCR results, sensitivity of SARS-CoV-2 RT-PCR and mortality during hospital admission. For the diagnostic risk score, we report discrimination, calibration and diagnostic accuracy of the model and simplified risk score and internal validation.

Results

4008 patients were admitted between 2 March and 3 May 2020. 1792 patients (44.8%) were diagnosed with COVID-19, of whom 1391 were SARS-CoV-2 RT-PCR positive and 283 had only negative RT-PCRs. Compared with a clinical reference standard, sensitivity of RT-PCR in hospital patients was 83.1% (95% CI 81.2%–84.8%). Broadly, patients with false-negative RT-PCR COVID-19 and those confirmed by positive PCR had similar demographic and clinical characteristics but lower risk of intensive care unit admission and lower in-hospital mortality (adjusted OR 0.41, 95% CI 0.27–0.61). A simple diagnostic risk score comprising of age, sex, ethnicity, cough, fever or shortness of breath, National Early Warning Score 2, C reactive protein and chest radiograph appearance had moderate discrimination (area under the receiver–operator curve 0.83, 95% CI 0.82 to 0.85), good calibration and was internally validated.

Conclusion

RT-PCR-negative COVID-19 is common and is associated with lower mortality despite similar presentation. Diagnostic risk scores could potentially help triage patients requiring admission but need external validation.
Visual mapping of team dynamics and communication patterns on surgical ward rounds: an ethnographic study
Authors: Bonaconsa Candice , Mbamalu Oluchi , Mendelson Marc , Boutall Adam , Warden Claire , Rayamajhi Shreya , Pennel Tim , Hampton Mark , Joubert Ivan , Tarrant Carolyn , Holmes Alison , Charani Esmita
Published: February 2021

Background

The effect of team dynamics on infection management and antimicrobial stewardship (AMS) behaviours is not well understood. Using innovative visual mapping, alongside traditional qualitative methods, we studied how surgical team dynamics and communication patterns influence infection-related decision making.

Materials/methods

Between May and November 2019, data were gathered through direct observations of ward rounds and face-to-face interviews with ward round participants in three high infection risk surgical specialties at a tertiary hospital in South Africa. Sociograms, a visual mapping method, mapped content and flow of communication and the social links between participants. Data were analysed using a grounded theory approach.

Results

Data were gathered from 70 hours of ward round observations, including 1024 individual patient discussions, 60 sociograms and face-to-face interviews with 61 healthcare professionals. AMS and infection-related discussions on ward rounds vary across specialties and are affected by the content and structure of the clinical update provided, consultant leadership styles and competing priorities at the bedside. Registrars and consultants dominate the discussions, limiting the input of other team members with recognised roles in AMS and infection management. Team hierarchies also manifest where staff position themselves, and this influences their contribution to active participation in patient care. Leadership styles affect ward-round dynamics, determining whether nurses and patients are actively engaged in discussions on infection management and antibiotic therapy and whether actions are assigned to identified persons.

Conclusions

The surgical bedside ward round remains a medium of communication between registrars and consultants, with little interaction with the patient or other healthcare professionals. A team-focused and inclusive approach could result in more effective decision making about infection management and AMS.
Hepatitis B virus integrations promote local and distant oncogenic driver alterations in hepatocellular carcinoma
Authors: Péneau Camille , Imbeaud Sandrine , La Bella Tiziana , Hirsch Theo Z , Caruso Stefano , Calderaro Julien , Paradis Valerie , Blanc Jean-Frederic , Letouzé Eric , Nault Jean-Charles , Amaddeo Giuliana , Zucman-Rossi Jessica
Published: February 2021

Objective

Infection by HBV is the main risk factor for hepatocellular carcinoma (HCC) worldwide. HBV directly drives carcinogenesis through integrations in the human genome. This study aimed to precisely characterise HBV integrations, in relation with viral and host genomics and clinical features.

Design

A novel pipeline was set up to perform viral capture on tumours and non-tumour liver tissues from a French cohort of 177 patients mainly of European and African origins. Clonality of each integration event was determined with the localisation, orientation and content of the integrated sequence. In three selected tumours, complex integrations were reconstructed using long-read sequencing or Bionano whole genome mapping.

Results

Replicating HBV DNA was more frequently detected in non-tumour tissues and associated with a higher number of non-clonal integrations. In HCC, clonal selection of HBV integrations was related to two different mechanisms involved in carcinogenesis. First, integration of viral enhancer nearby a cancer-driver gene may lead to a strong overexpression of oncogenes. Second, we identified frequent chromosome rearrangements at HBV integration sites leading to cancer-driver genes (TERT, TP53, MYC) alterations at distance. Moreover, HBV integrations have direct clinical implications as HCC with a high number of insertions develop in young patients and have a poor prognosis.

Conclusion

Deep characterisation of HBV integrations in liver tissues highlights new HBV-associated driver mechanisms involved in hepatocarcinogenesis. HBV integrations have multiple direct oncogenic consequences that remain an important challenge for the follow-up of HBV-infected patients.
Clinical and laboratory characteristics in outpatient diagnosis of COVID-19 in healthcare professionals in Rio de Janeiro, Brazil
Authors: Porto Luis Cristovao , Costa Claudia H , Nunes Alessandra S , Bouzas Isabel , Ferreira Tiago F , Porto Vinicius M , Secco Danielle A , Vilas Boas Sandra , Faria Anamelia Costa , Rufino Rogerio
Published: February 2021

Aims

This study aimed to identify the symptoms associated with early stage SARS-CoV-2 (COVID-19) infections in healthcare professionals (HCPs) using both clinical and laboratory data.

Methods

A total of 1297 patients, admitted between 18 March and 8 April 2020, were stratified according to their risk of developing COVID-19 using their responses to a questionnaire designed to evaluate symptoms and risk conditions.

Results

Anosmia/hyposmia (p<0.0001), fever (p<0.0001), body pain (p<0.0001) and chills (p=0.001) were all independent predictors for COVID-19, with a 72% estimated probability for detecting COVID-19 in nasopharyngeal swab samples. Leucopenia, relative monocytosis, decreased eosinophil values, C reactive protein (CRP) and platelets were also shown to be significant independent predictors for COVID-19.

Conclusions

The significant clinical features for COVID-19 were identified as anosmia, fever, chills and body pain. Elevated CRP, leucocytes under 5400×109/L and relative monocytosis (>9%) were common among patients with a confirmed COVID-19 diagnosis. These variables may help, in the absence of reverse transcriptase PCR tests, to identify possible COVID-19 infections during pandemic outbreaks.

From 19 March to 8 April 2020, 1297 patients attended the Polyclinic Piquet Carneiro for COVID-19 detection. HCP data were analysed, and significant clinical features were anosmia, fever, chills and body pain. Elevated CRP, leucopenia and monocytosis were common in COVID-19.
Detection ofHelicobacter pyloriin virtual slides requires high resolution digitalisation
Authors: Uguen Arnaud
Published: February 2021

To diagnoseHelicobacter pylori(HP) infection and its related mucosal injuries requires the histopathological analysis of gastric biopsies. The move from glass slides interpretation towards digital pathology implies technical choices to maintain the performances of histopathological diagnosis. The intra-rater agreement in assessing gastritis diagnostic criteria between glass slides, low resolution and high resolution digital slides in the subject of the present study. One hundred gastric biopsies were re-assessed by a single digestive pathologist on glass slides and digitalised slides at low resolution (ie, x20 magnification and single focus without z-stack) and high resolution (ie, x40 magnification with seven focus levels and z-stack) about the criteria of the updated Sydney system and the detection of HP. Inter-analyses agreement were very good (Kappa values>0.81) for every criteria but slightly inferior (ie, Kappa values<0.9) comparing glass slides interpretations with low resolution digital slides-based ones. Indeed, some HP infections were misdiagnosed using x20 magnification histochemical stained digitalised slides (p<0.05). At the opposite, anti-HP immunohistochemistry slides and/or x40 magnification digitalisation permitted to maintain almost perfect concordance in diagnosis (Kappa value>0.9). As mentioned in current guidelines, a high resolution x40 magnification digitalisation must be favoured in order to avoid some misdetection of microorganisms as HP.
Four-year trajectories of episodic memory decline in mid-late life by living arrangements: a cross-national comparison between China and England
Authors: Hu Yaoyue , Ruiz Milagros , Bobak Martin , Martikainen Pekka
Published: February 2021

Background

There is mixed evidence on the association between living arrangements and mid-late life cognition, which may be due to distinct familial arrangements and preferences between populations. To address such heterogeneity, we assessed these associations in China and England.

Methods

Four-year trajectories of episodic memory scores (0–20, word recall test) by living arrangements (living with partner only, living with partner and children/grandchildren, living with no partner but with children/grandchildren, and living alone) were estimated using latent growth curve modelling for men and women aged 50+ from China (n=12 801) and England (n=10 964).

Results

After adjusting for baseline socioeconomic, health behaviours and health covariates, worse baseline memory was found in Chinese adults living with no partner but with children/grandchildren and in Chinese women living with partner and children/grandchildren, compared with those living with partner only. Better baseline memory was associated with living alone in English women. A faster memory decline was found in Chinese men living with no partner but with children/grandchildren (−0.122 word/year, 95% CI −0.213 to –0.031), as well as in English women living with children/grandchildren with (−0.114, 95% CI −0.180 to –0.049) or without (−0.118, 95% CI −0.209 to –0.026) a partner, and those living alone (−0.075, 95% CI −0.127 to –0.024). No differences at baseline nor over follow-up were found between English men in different living arrangements.

Conclusion

Overall, our findings did not confirm the protective effects of co-residence with children/grandchildren, nor the detrimental effects of living alone on mid-late life cognition in China and England.
Universal germline testing among patients with colorectal cancer: clinical actionability and optimised panel
Authors: Jiang Wu , Li Lin , Ke Chuan-Feng , Wang Wei , Xiao Bin-Yi , Kong Ling-Heng , Tang Jing-Hua , Li Yuan , Wu Xiao-Dan , Hu Ying , Guo Wei-Hua , Wang Si-Zhen , Wan De-Sen , Xu Rui-Hua , Pan Zhi-Zhong , Ding Pei-Rong
Published: February 2021

Purpose

Universal germline testing in patients with colorectal cancer (CRC) with a multigene panel can detect various hereditary cancer syndromes. This study was performed to understand how to choose a testing panel and whether the result would affect clinical management.

Methods

We prospectively enrolled 486 eligible patients with CRC, including all patients with CRC diagnosed under age 70 years and patients with CRC diagnosed over 70 years with hereditary risk features between November 2017 and January 2018. All participants received germline testing for various hereditary cancer syndromes.

Results

The prevalence of germline pathogenic variants (PVs) in cancer susceptibility genes was 7.8% (38/486), including 25 PVs in genes with high-risk CRC susceptibility (the minimal testing set) and 13 PVs in genes with moderate-risk CRC susceptibility or increased cancer risk other than CRC (the additional testing set). All the clinically relevant PVs were found in patients diagnosed under age 70 years. Among them, 11 patients would not have been diagnosed if testing reserved to present guidelines. Most (36/38) of the patients with PVs benefited from enhanced surveillance and tailored treatment. PVs in genes from the minimal testing set were found in all age groups, while patients carried PVs in genes from the additional testing set were older than 40 years.

Conclusion

Universal germline testing for cancer susceptibility genes should be recommended among all patients with CRC diagnosed under age 70 years. A broad panel including genes from the additional testing set might be considered for patients with CRC older than 40 years to clarify inheritance risks.

Trial registration number

NCT03365986.
Cerebral microbleeds: from depiction to interpretation
Authors: Puy Laurent , Pasi Marco , Rodrigues Mark , van Veluw Susanne J , Tsivgoulis Georgios , Shoamanesh Ashkan , Cordonnier Charlotte
Published: February 2021

Cerebral microbleeds (CMBs) are defined as hypointense foci visible on T2*-weighted and susceptible-weighted MRI sequences. CMBs are increasingly recognised with the widespread use of MRI in healthy individuals as well as in the context of cerebrovascular disease or dementia. They can also be encountered in major critical medical conditions such as in patients requiring extracorporeal mechanical oxygenation. The advent of MRI-guided postmortem neuropathological examinations confirmed that, in the context of cerebrovascular disease, the vast majority of CMBs correspond to recent or old microhaemorrhages. Detection of CMBs is highly influenced by MRI parameters, in particular field strength, postprocessing methods used to enhance T2* contrast and three dimensional sequences. Despite recent progress, harmonising imaging parameters across research studies remains necessary to improve cross-study comparisons. CMBs are helpful markers to identify the nature and the severity of the underlying chronic small vessel disease. In daily clinical practice, presence and numbers of CMBs often trigger uncertainty for clinicians especially when antithrombotic treatments and acute reperfusion therapies are discussed. In the present review, we discuss those clinical dilemmas and address the value of CMBs as diagnostic and prognostic markers for future vascular events.
Psychotropic and pain medication use in individuals with traumatic brain injury—a Swedish total population cohort study of 240 000 persons
Authors: Molero Yasmina , Sharp David James , D'Onofrio Brian Matthew , Larsson Henrik , Fazel Seena
Published: February 2021

Objective

To examine psychotropic and pain medication use in a population-based cohort of individuals with traumatic brain injury (TBI), and compare them with controls from similar backgrounds.

Methods

We assessed Swedish nationwide registers to include all individuals diagnosed with incident TBI between 2006 and 2012 in hospitals or specialist outpatient care. Full siblings never diagnosed with TBI acted as controls. We examined dispensed prescriptions for psychotropic and pain medications for the 12 months before and after the TBI.

Results

We identified 239 425 individuals with incident TBI, and 199 658 unaffected sibling controls. In the TBI cohort, 36.6% had collected at least one prescription for a psychotropic or pain medication in the 12 months before the TBI. In the 12 months after, medication use increased to 45.0%, an absolute rate increase of 8.4% (p<0.001). The largest post-TBI increases were found for opioids (from 16.3% to 21.6%, p<0.001), and non-opioid pain medications (from 20.3% to 26.6%, p<0.001). The majority of prescriptions were short-term; 20.6% of those prescribed opioids and 37.3% of those with benzodiazepines collected prescriptions for more than 6 months. Increased odds of any psychotropic or pain medication were associated with individuals before (OR: 1.62, 95% CI: 1.59 to 1.65), and after the TBI (OR: 2.30, 95% CI: 2.26 to 2.34) as compared with sibling controls, and ORs were consistently increased for all medication classes.

Conclusion

High rates of psychotropic and pain medications after a TBI suggest that medical follow-up should be routine and review medication use.
Cognitive reserve in amyotrophic lateral sclerosis (ALS): a population-based longitudinal study
Authors: Costello Emmet , Rooney James , Pinto-Grau Marta , Burke Tom , Elamin Marwa , Bede Peter , McMackin Roisin , Dukic Stefan , Vajda Alice , Heverin Mark , Hardiman Orla , Pender Niall
Published: February 2021

Background

Amyotrophic lateral sclerosis (ALS) is often associated with cognitive and/or behavioural impairment. Cognitive reserve (CR) may play a protective role in offsetting cognitive impairment. This study examined the relationship between CR and longitudinal change in cognition in an Irish ALS cohort.

Methods

Longitudinal neuropsychological assessment was carried out on 189 patients over 16 months using the Edinburgh cognitive and behavioural ALS screen (ECAS) and an additional battery of neuropsychological tests. CR was measured by combining education, occupation and physical activity data. Joint longitudinal and time-to-event models were fitted to investigate the associations between CR, performance at baseline and decline over time while controlling for non-random drop-out.

Results

CR was a significant predictor of baseline neuropsychological performance, with high CR patients performing better than those with medium or low CR. Better cognitive performance in high CR individuals was maintained longitudinally for ECAS, social cognition, executive functioning and confrontational naming. Patients displayed little cognitive decline over the course of the study, despite controlling for non-random drop-out.

Conclusions

These findings suggest that CR plays a role in the presentation of cognitive impairment at diagnosis but is not protective against cognitive decline. However, further research is needed to examine the interaction between CR and other objective correlates of cognitive impairment in ALS.
Chronic inflammatory demyelinating polyneuropathy and pregnancy: systematic review
Authors: Kohle Felix , Kuwabara Satoshi , Lehmann Helmar Christoph
Published: February 2021

Pregnancy largely affects disease activity and clinical course in women with immune-mediated neurological disorders. Chronic inflammatory demyelinating polyneuropathy (CIDP) is rare but the most common chronic immune-mediated neuropathy; however, the effects of pregnancy on CIDP have never been investigated except case reports or series. We here provide a systematic review of the literature from 1 January 1969 to 30 June 2020 that revealed 24 women with CIDP, who had onset or relapse during pregnancy. Of these, 17 (71%) developed CIDP during the first pregnancy, and 8 (47%) had a relapse during subsequent pregnancies. Of the 17 patients, in whom the CIDP subtypes were determined, all of them had typical CIDP. First-line treatments for CIDP, such as corticosteroids, immunoglobulin and plasma exchange were efficacious and safe. We suggest that pregnancy can trigger typical CIDP in some women, and women with CIDP have a higher risk of relapse during pregnancy. The onset or relapse of CIDP during pregnancy is a rare but challenging constellation for physicians.
Risk factors for cognitive impairment in amyotrophic lateral sclerosis: a systematic review and meta-analysis
Authors: Yang Tianmi , Hou Yanbing , Li Chunyu , Cao Bei , Cheng Yangfan , Wei Qianqian , Zhang Lingyu , Shang Huifang
Published: February 2021

Objective

Cognitive impairment is a common, far-reaching but imperceptible manifestation in patients with amyotrophic lateral sclerosis (ALS). We aimed to identify the risk factors for cognitive impairment in ALS.

Methods

We searched PubMed and EMBASE for cross-sectional, case–control and cohort studies that reported predictors of cognitive impairment in ALS. The obtained data were meta-analysed to generate overall ORs and 95% CIs.

Results

Twenty-seven eligible articles reporting on 6799 individuals were included out of 20 501 records. Nine predictors were identified: C9orf72 (OR 3.62, 95% CI 1.76 to 7.45), dysarthria (OR 2.25, 95% CI 1.20 to 4.22), family history of ALS (OR 1.76, 95% CI 1.18 to 2.61), predominant upper motor neuron (PUMN) phenotype (OR 1.73, 95% CI 1.09 to 2.73) and bulbar onset (OR 1.54, 95% CI 1.28 to 1.87) increased risk factors for cognitive impairment in ALS. ALS Functional Rating Scale-Revised scores, sex, age or education level were not significantly associated with cognitive impairment in ALS. In addition, C9orf72 (OR=5.94) and bulbar onset (OR=2.08) were strong predictors of ALS-frontotemporal dementia. Female sex conferred more susceptibility to executive cognitive impairment than male sex (OR=1.82).

Conclusions

Patients with C9orf72 repeat expansion, dysarthria, family history of ALS, PUMN phenotype and bulbar onset had a high risk for cognitive impairment in ALS. These associations may contribute to understanding the heterogeneity of ALS.

PROSPERO registration number

CRD42020201085.
Effect of sodium-glucose cotransporter-2 inhibitors on renal handling of electrolytes
Authors: Meena Priti , Bhargava Vinant , Bhalla Anil , Rana Devinder , Mantri Alok
Published: February 2021

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) are the latest introduction into the armamentarium of diabetes care in the present decade. By virtue of their beneficial effects, such as blood pressure-lowering, bodyweight reduction and significant renal and cardioprotective effects which extends beyond their glycaemic control effects, SGLT2i have become one of the most preferred oral antihyperglycaemic agents of recent times. However, they can influence tubular handling of electrolytes that can result in some electrolyte disturbances such as alteration in the serum levels of magnesium, potassium and phosphate levels. Some of these changes are mild or transient and may not have significant clinical implications. The underlying putative mechanism(s) responsible for disturbances of electrolytes are yet to be deciphered. In this review, we aim to describe electrolytes and acid–base abnormalities due to SGLT2i as well as to elucidate the underlying mechanism.
What do beta-lactams add to vancomycin or daptomycin in the treatment of patients with methicillin-resistantStaphylococcus aureusbacteraemia? A review
Authors: García Aragonés Laura , Blanch Sancho José Javier , Segura Luque Juan Carlos , Mateos Rodriguez Fernando , Martínez Alfaro Elisa , Solís García del Pozo Julián
Published: February 2021

Several studies have documented the synergy between vancomycin/daptomycin and various beta-lactams, and clinical studies have studied this combination therapy in humans. We review the published literature on this topic to know the utility of the combined treatment with beta-lactams in treating bacteraemia methicillin-resistant Staphylococcus aureus (MRSA) infections. Fifteen observational studies, three randomised clinical trials and three systematics reviews are analysed in this article. Observational studies used ceftaroline, cefazolin, piperacillin/tazobactam or cefepime among the beta-lactams. Clinical trials used cloxacillin or flucloxacillin as the most used beta-lactam in two trials and ceftaroline in one. Three systematic reviews are published. One of them only includes studies with vancomycin and included six studies. The other two systematic reviews include patients with daptomycin or vancomycin and included 15 and 9 studies, respectively. Adding a beta-lactam to vancomycin or daptomycin may help shorten bacteraemia and avoid recurrences in patients with MRSA bacteraemia. There is no evidence that combined therapy improves mortality. Nephrotoxicity in clinical trials precludes the use of combination therapy mainly with cloxacillin or flucloxacillin, but systematic reviews have not found a significant difference in this point in observational studies with other beta-lactams. The role of other beta-lactams such as ceftaroline should be thoroughly studied in these patients.
Guidance for providing effective feedback in clinical supervision in postgraduate medical education: a systematic review
Authors: Weallans Jessica , Roberts Caroline , Hamilton Sarah , Parker Stephen
Published: February 2021

The primary aim was to systematically review the empirical evidence relating to models and guidance for providing effective feedback in clinical supervision occurring in postgraduate medical education contexts. A secondary aim was to identify the common and differentiating components of models and guidance for providing effective feedback in this context. A systematic review was conducted. Fifty-one records met the inclusion criteria, including 12 empirical studies. Empirical records meeting inclusion criteria were critically appraised. Qualitative content analysis was applied to the guidance on effective and ineffective feedback provision to identify key principles. A composite model was created synthesising the guidance identified for providing effective feedback. The evidence supporting specific models and guidance in postgraduate medical education was limited. However, there is evidence to support all of the commonly identified principles. In addition, a consensus about the principles of effective feedback in clinical supervision in postgraduate medical education was found.
Skeletal muscle channelopathies: a guide to diagnosis and management
Authors: Matthews Emma , Holmes Sarah , Fialho Doreen
Published: February 2021

Skeletal muscle channelopathies are a group of rare episodic genetic disorders comprising the periodic paralyses and the non-dystrophic myotonias. They may cause significant morbidity, limit vocational opportunities, be socially embarrassing, and sometimes are associated with sudden cardiac death. The diagnosis is often hampered by symptoms that patients may find difficult to describe, a normal examination in the absence of symptoms, and the need to interpret numerous tests that may be normal or abnormal. However, the symptoms respond very well to holistic management and pharmacological treatment, with great benefit to quality of life. Here, we review when to suspect a muscle channelopathy, how to investigate a possible case and the options for therapy once a diagnosis is made.
Degradation of crumb rubber modified railway ballast under impact loading considering aggregate gradation and rubber size
Authors: Koohmishi Mehdi , Azarhoosh Alireza
Published: February 2021

Impact loads generated from the dynamic effect of passing trains can exacerbate the degradation level of ballast aggregate of railway track. To diminish the induced impact loads, the use of crumb rubber (CR) in the ballast course is characterized as a well-established procedure related to the modification of utilized material. Nonetheless, more in-depth assessments of size and percentage of CR particles combined with ballast aggregate are still required. The present study evaluates the influence of size and content of CR particles used for degradation reduction of ballast aggregate subjected to impact loading. For this purpose, a large-scale impact loading test is carried out on prepared specimens of aggregate by considering the initial gradation, subgrade condition, as well as the size and content of CR particles. The results indicate less ballast degradation for a higher percentage of CR particles. Meanwhile, the enhancement of rubber modified ballast against deterioration is further highlighted in the case of rigid subgrade. In addition, incorporation of larger-sized CR particles (12.5–25 mm) in a ballast specimen comprising more uniform gradation of aggregate can more effectively diminish the amount of degradation. Nevertheless, using smaller-sized CR particles (4.75–9.5 mm) for a ballast sample consisting of a broader range of sizes can better improve resistance against degradation.
Viscous properties of hot and dense QCD matter in the presence of a magnetic field
Authors: Rath Shubhalaxmi , Patra Binoy Krishna
Published: February 2021

We have studied the effect of strong magnetic field on the viscous properties of hot QCD matter at finite chemical potential by calculating the shear viscosity ($$\eta $$
η
) and the bulk viscosity ($$\zeta $$
ζ
). The viscosities have been calculated using the relativistic Boltzmann transport equation within the relaxation time approximation. The interactions among partons are incorporated through their quasiparticle masses at finite temperature, strong magnetic field and finite chemical potential. From this study, one can understand the influence of strong magnetic field and the influence of chemical potential on the sound attenuation through the Prandtl number (Pl), on the nature of the flow by the Reynolds number (Rl), and on the relative behavior between the shear viscosity and the bulk viscosity through the ratio $$\zeta /\eta $$

ζ
/
η

. We have observed that, both shear and bulk viscosities get increased in the presence of a strong magnetic field and the additional presence of chemical potential further enhances their magnitudes. With the increase of temperature, $$\eta $$
η
increases for the medium in the presence of a strong magnetic field as well as for the isotropic medium in the absence of magnetic field, whereas $$\zeta $$
ζ
is found to decrease with the temperature, contrary to its increase in the absence of magnetic field. We have observed that, the Prandtl number gets increased in the presence of strong magnetic field and finite chemical potential as compared to that in the isotropic medium, but it always remains larger than unity, thus instead of the thermal diffusion, the momentum diffusion largely affects the sound attenuation in the medium and this is more vigorous in the presence of both strong magnetic field and finite chemical potential. However, the Reynolds number becomes lowered than unity in an ambience of strong magnetic field and even gets further decreased in an additional presence of chemical potential, thus it implies the dominance of kinematic viscosity over the characteristic length scale of the system. Finally, the ratio $$\zeta /\eta $$

ζ
/
η

is amplified to the value larger than unity, contrary to its value in the absence of magnetic field and chemical potential where it is less than unity, thus it is inferred that the bulk viscosity prevails over the shear viscosity for the hot and dense QCD matter in the presence of a strong magnetic field.
A Fast Algorithm for Knapsack Problem with Conflict Graph
Authors: Li Jiaxin , Lan Yan , Chen Feng , Han Xin , Blazewicz Jacek
Published: February 2021

In this paper, we propose a fast algorithm based on a new algorithm to calculate the upper bound for the knapsack problem with conflict graph (KPCG). The KPCG is an extension of the 0-1 knapsack problem. A pre-defined conflict graph defines the incompatibility properties between pairs of items. The goal is to determine which items should be packed into the knapsack to maximize the total profit on the premise of satisfying the capacity constraint and the incompatibility constraints. The experimental results show that for the graph with density greater than or equal to 0.1, the branch-and-bound algorithm based on the new algorithm is 1.6458 and 1.6352 times faster than the state-of-the-art algorithm on random and correlated instances, respectively, and can achieve speedups of up to 4.6477 for some low density instances. Moreover, the branch-and-bound algorithm based on the new algorithm can optimally solve more instances than the state-of-the-art algorithm in a given time limit.
Formation of strong-coupling (bi)polarons and related in-gap states in lightly-doped cuprate superconductors
Authors: Dzhumanov S. , Sabirov S. S. , Karimbaev E. X. , Rashidov J. Sh. , Djumanov D. S. , Kurbanov U. T. , Sheraliev M. U.
Published: February 2021

The formation of large polarons and bipolarons and related in-gap states in lightly-doped cuprates is studied in the strong electron–phonon coupling regime. The ground-state energies, binding energies and binding radius of strong-coupling large (bi)polarons are calculated using the continuum model and adiabatic approximation taking into account both the short- and long-range electron–phonon interactions. The obtained results show that the binding energies of such large (bi)polarons in the cuprates are progressively increased with decrease in the high frequency dielectric constant [Formula: see text] and ratio [Formula: see text] (where [Formula: see text] is the static dielectric constant). As a result, large (bi)polarons become nearly small (bi)polarons. It is shown that hole carriers strongly interact with acoustic and optical phonons and their self-trapping leads to the formation of (bi)polaronic states in the charge-transfer (CT) gap of the cuprates. As the cuprate system is doped, the CT gap of the parent compound is filled in with low-energy (bi)polaronic states. The calculated energies of such (bi)polaronic states are in good agreement with the experimentally observed energies of new states appearing in the CT gap of the parent cuprates. The calculated values of the binding radius of large polarons are also well consistent with the existing experimental data.
Shape programming of a magnetic elastica
Authors: Durastanti Riccardo , Giacomelli Lorenzo , Tomassetti Giuseppe
Published: February 2021

We consider a cantilever beam which possesses a possibly non-uniform permanent magnetization, and whose shape is controlled by an applied magnetic field. We model the beam as a plane elastic curve and we suppose that the magnetic field acts upon the beam by means of a distributed couple that pulls the magnetization towards its direction. Given a list of target shapes, we look for a design of the magnetization profile and for a list of controls such that the shapes assumed by the beam when acted upon by the controls are as close as possible to the targets, in an averaged sense. To this effect, we formulate and solve an optimal design and control problem leading to the minimization of a functional which we study by both direct and indirect methods. In particular, we prove that minimizers exist, solve the associated Lagrange-multiplier formulation (besides non-generic cases), and are unique at least for sufficiently low intensities of the controlling magnetic fields. To achieve the latter result, we use two nested fixed-point arguments relying on the Lagrange-multiplier formulation of the problem, a method which also suggests a numerical scheme. Various relevant open question are also discussed.
A Hybrid Approach for the Dynamic Instability Analysis of Single-Layer Latticed Domes with Uncertainties
Authors: An Ning , Zhang Huidong , Zhu Xinqun , Xu Fei
Published: February 2021

Currently, there is no unified criterion to evaluate the failure of single-layer latticed domes, and an accurate nonlinear time-history analysis (NTHA) is generally required; however, this does not consider the uncertainties found in practice. The seismic instability of domes subjected to earthquake ground motions has not been thoroughly investigated. In this paper, a new approach is developed to automatically capture the instability points in the incremental dynamic analysis (IDA) of single-layer lattice domes by integrating different efficient and robust methods. First, a seismic fragility analysis with instability parameters is performed using the bootstrap calibration method for the perfect dome. Second, based on the Sobol sequence, the quasi-Monte Carlo (QMC) sampling method is used to efficiently calculate the failure probability of the dome with uncertain parameters, in which the truncated distributions of random parameters are considered. Third, the maximum entropy principle (MEP) method is used to improve the computational efficiency in the analyses of structures with uncertainties. Last, the uncertain interval of the domes is determined based on the IDA method. The proposed method has been used to investigate the instability of single-layer lattice domes with uncertain parameters. The results show that it can determine the probability of structural failure with high efficiency and reliability. Additionally, the limitations of the proposed method for parallel computation are discussed.
On checkable codes in group algebras
Authors: Borello Martino , De La Cruz Javier , Willems Wolfgang
Published: February 2021

We classify, in terms of the structure of the finite group G, all group algebras KG for which all right ideals are right annihilators of principal left ideals. This means in the language of coding theory that we classify code-checkable group algebras KG which have been considered so far only for abelian groups G. Optimality of checkable codes and asymptotic results are discussed.
Locally unital quantum B-algebras
Authors: Han Shengwei , Bao Zhigang
Published: February 2021

In this paper, we mainly consider three classes of quantum B-algebras such as locally unital quantum B-algebras, two-sided quantum B-algebras and implication-commutative quantum B-algebras. We first prove that a quantum B-algebra can be embedded into a unital quantum B-algebra if and only if it is a locally unital quantum B-algebra. Next, we introduce two-sided (implication-commutative) quantum B-algebras and give their characterization. Based on which we finally investigate the filters of quantum B-algebras.
Learning theory of minimum error entropy under weak moment conditions
Authors: Huang Shouyou , Feng Yunlong , Wu Qiang
Published: February 2021

Minimum error entropy (MEE) is an information theoretic learning approach that minimizes the information contained in the prediction error, which is measured by entropy. It has been successfully used in various machine learning tasks for its robustness to heavy-tailed distributions and outliers. In this paper, we consider its use in nonparametric regression and analyze its generalization performance from a learning theory perspective by imposing a [Formula: see text]th order moment condition on the noise variable. To this end, we establish a comparison theorem to characterize the relation between the excess generalization error and the prediction error. A relaxed Bernstein condition and concentration inequalities are used to derive error bounds and learning rates. Note that the [Formula: see text]th moment condition is rather weak particularly when [Formula: see text] because the noise variable does not even admit a finite variance in this case. Therefore, our analysis explains the robustness of MEE in the presence of heavy-tailed distributions.
Complete classification of cosmological teleparallel geometries
Authors: Hohmann Manuel
Published: February 2021

We consider the notion of cosmological symmetry, i.e. spatial homogeneity and isotropy, in the field of teleparallel gravity and geometry, and provide a complete classification of all homogeneous and isotropic teleparallel geometries. We explicitly construct these geometries by independently employing three different methods, and prove that all of them lead to the same class of geometries. Further, we derive their properties, such as the torsion tensor and its irreducible decomposition, as well as the transformation behavior under change of the time coordinate, and derive the most general cosmological field equations for a number of teleparallel gravity theories. In addition to homogeneity and isotropy, we extend the notion of cosmological symmetry to also include spatial reflections, and find that this further restricts the possible teleparallel geometries. This work answers an important question in teleparallel cosmology, in which so far only particular examples of cosmologically symmetric solutions had been known, but it was unknown whether further solutions can be constructed.
Geometric magnetic phase for timelike spherical optical ferromagnetic model
Authors: Korpinar Talat
Published: February 2021

In this paper, we give some constructions for the applications of optical magnetic Heisenberg spherical ferromagnetic chain of T - timelike magnetic particle by spherical de Sitter frame in de Sitter space. This aim may be concluded by well-known de Sitter frame or a new alternative spherical frame with an optical magnetic spherical Heisenberg ferromagnetic chain. Moreover, we achieve total magnetic phases of T - timelike magnetic particle evolutions. Finally, we obtain some numerical modeling of optical magnetic spherical Heisenberg ferromagnetic flows.
Data-driven derivation of partial differential equations using neural network model
Authors: Koyamada Koji , Long Yu , Kawamura Takuma , Konishi Katsumi
Published: February 2021

It has become critical to develop explanatory models using partial differential equations (PDEs) for big data from interesting scientific phenomena, e.g., fluids, atmosphere, and cosmic phenomena. Big data are often measured at discrete spatiotemporal points. In this paper, we assume a PDE and consider a set of the PDE solution data at multiple discrete points as pseudo-measurement data. In a data-driven PDE derivation, it is assumed that the PDE is a linear regression model comprising partial temporal and spatial differential terms, where the coefficients are estimated using regression analysis techniques, and the PDE derivation accuracy is defined as the difference (i.e., error) between the exact and estimated coefficients. A spatiotemporal model is required to calculate the partial temporal and spatial differential terms; thus, we employ a spatiotemporal model based on a neural network (NN) obtained from big data. To develop the data-driven PDE derivation technique, we employ PDEs with exact solutions such that we can calculate the differential terms by differentiating them analytically at multiple discrete points. If we assume an activation function in the NN model, the partial differential term can be derived using a chain rule. The NN model accuracy is measured by the loss function and error between the exact and estimated partial differential terms. In addition, we clarify a requirement for an NN structure that can maximize the PDE derivation and NN model accuracy by varying the NN meta-parameters, i.e., the numbers of NN layers and neurons.