bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of radiation-associated deformation in the electrical properties of metal-polymer semiconductor
Authors: Gokmen Uğur
Published: March 2021

In the present study, rubrene-based Schottky barrier structures have been formed by using the evaporation technique to investigate the conductance–voltage (G–V) and capacitance-voltage (C–V) values of the effect of the 60Co gamma-ray irradiation. The conductance and capacitance values were measured before and after 60Co gamma-ray radiation at 100 kHz, 500 kHz and 1 MHz. The frequency-dependent effects of interface state density and series resistance with and without irradiation in dark were analyzed at room temperature. The analysis results imply that values of forward and reverse C characteristics decrease the rate depending on gamma-ray irradiation and the increment of voltage due to the exchange of majority carriers between the majority carrier band of semiconductor and interface states. The irradiation dose and frequency increase show irradiation dispersion at the accumulation region when an A.C. signal is applied to the semiconductor structures. The G–V characteristics of rubrene-based Schottky barrier structures change with gamma radiation dose at different frequencies. Also, these characteristics relate to the density of the interface states. The analyses reveal that D

it
values decrease with the increase in frequency before 60Co gamma-ray irradiation. These values also decrease with the increase in frequency at the same radiation doses after 60Co gamma-ray irradiation. They decrease with the increase in irradiation doses at the same frequency, except for 100 kHz. Experimental results indicate that rubrene-based Schottky barrier structures can be altered using 60Co gamma-ray irradiation. The experimental contributions indicate a substantial step forward in the structure-function relationship in the benchmark organic semiconductors.
Design of high-performance guns for the HL-LHC HEL
Authors: Perini D. , Kolhemainen A. , Rossi A. , Sadovich S. , Stancari G.
Published: March 2021

The High Luminosity LHC project (HL-LHC) foresees the
construction and installation of important new equipment to increase
the performance of the LHC machine. The Hollow Electron Lens (HEL)
is a promising system to control the beam halo. It improves the beam
collimation system of the HL-LHC and mitigates possible equipment
damage in case of failure scenarios from halo losses. The halo can
store up to 30 MJ energy. The specifications for this new device
are quite demanding. The source, an electron gun with an annular
shaped cathode, must deliver a current up to 5 A. This is five
times higher than the current in the existing electron lenses in
Fermi and Brookhaven national laboratories. This note describes the
programme carried out to design and test high-perveance guns
equipped with two types of high-performance scandate cathodes. The
size of the final gun for the HL-LHC lenses is now considerably
smaller than the one of the first prototype, allowing a reduction of
diameter and cost of the superconducting magnet system used to steer
the electron beam. The tests carried out at FNAL, BVERI and BJUT
demonstrated that the developed cathodes fulfil the specifications
and can supply a 5 A fully Space Charge Limited (SCL) current.
Modulation of winter precipitation associated with tropical cyclone of the western North Pacific by the stratospheric Quasi-Biennial oscillation
Authors: Wang Lei , Wang Lin , Chen Wen , Huangfu Jingliang
Published: March 2021

Tropical cyclone precipitation (TCP) has increasing impacts on many coastal regions under global warming. Causes of TCP variation have been principally explored in the troposphere. This study identifies the significant modulation of the stratosphere Quasi-Biennial oscillation (QBO) on the winter TCP in the coastal regions of the western North Pacific (WNP). In the westerly QBO winter, the zonal wind vertical shear anomalies in the stratosphere strengthen (weaken) convective activities around the East China Sea (the Philippines) and cause middle-level easterly (westerly) anomalies of the middle (low) latitudes in the troposphere, leading to more (less) TC activities around the East China Sea (the Philippines). Consequently, a TCP dipole pattern can be observed. The TCP increases in East China, Korean peninsula, Japan and Russian Far East, but decreases in Indo–China Peninsula, South China and the Philippines. These results not only improve the knowledge of QBO-TCP relationship but also provide a potential indicator for the seasonal prediction of the TCP in the coastal regions of the WNP due to the high predictability of the QBO.
A Green’s function approach to the linear response of a driven dissipative optomechanical system
Authors: Motazedifard Ali , Dalafi A , Naderi M H
Published: March 2021

In this paper, we first try to shed light on the ambiguities that exist in the literature in the generalization of the standard linear response theory (LRT) which has been basically formulated for closed systems to the theory of open quantum systems in the Heisenberg picture. Then, we investigate the linear response of a driven-dissipative optomechanical system (OMS) to a weak time-dependent perturbation using the so-called generalized LRT. It is shown how the Green’s function equations of motion of a standard OMS as an open quantum system can be obtained from the quantum Langevin equations (QLEs) in the Heisenberg picture. The obtained results explain a wealth of phenomena, including the anti-resonance, normal mode splitting and the optomechanically induced transparency (OMIT). Furthermore, the reason why the Stokes or anti-Stokes sidebands are amplified or attenuated in the red or blue detuning regimes is clearly explained which is in exact coincidence, especially in the weak-coupling regime, with the Raman-scattering picture.
The use of natural zeolites from Gunungkidul, Indonesia for preventing arsenic pollution of soils and plants
Authors: Budianta W
Published: March 2021

The impact of mining activity is soil pollution caused by mining waste. The objective of this study was to investigate the potential use of natural zeolite for stabilization arsenic in contaminated soil. The soil samples were obtained from the mining area in the top layer and subsurface and then analyzed for arsenic concentrations. Immobilization experiment was conducted by using natural zeolite from Gunungkidul, Yogyakarta, and the effects of natural zeolites in preventing of arsenic were investigated by assessed Jatropha curcas plant. Immobilization experiment revealed that by adding natural zeolites will decrease the concentrations of arsenic in plant material and suitable for sandy and loamy soil. This result is essential for preventing point leading to the entry of arsenic into the food chain.
Soil erosion mapping using GIS based model in agricultural area of Progo watershed, Central Java, Indonesia
Authors: Seika A N , Setyawan C , Ngadisih  , Tirtalistyani R
Published: March 2021

Soil erosion remains a strenuous problem for agricultural practices, particularly in tropical regions as happened in Indonesia. This study aimed to investigate the distribution of soil erosion in agricultural areas of a tropical watershed. The Revised Universal Soil Loss Equation (RUSLE) model in a Geographic Information System (GIS) was used for soil erosion assessment. RUSLE model parameters were collected from various sources. Soil erosion was classified into five classes such as very low (0-15 t ha−1 yr−1), low (15-60 t ha−1 yr−1), moderate (60-180 t ha−1 yr−1), heavy (180-480 t ha−1 yr−1), and very heavy (>480 t ha−1 yr−1). The result showed that the average soil erosion in the study site was 71.1 t ha−1 yr−1. More than 50% of the study site was occupied by very low class soil erosion, while heavy and very heavy class soil erosion occupied more than 20% of the study site. The finding of this study provides a useful reference for soil erosion control and studies.
The Population Structure and Presence of Helopeltis bradyi on the Tea Plant Parts at Various Times During the Day
Authors: Wagiman F X , Sari N M , Wijonarko A
Published: March 2021

Behavioural characteristics of the tea mosquito bug,Helopeltis bradyi, are important to be understood to support the control efforts of the pest. The study was aimed to describe population structure and behaviour ofH. bradyion the tea plant parts. The field study was conducted at Pagilaran tea plantation located in Batang Regency, Central Java Province, at 870 m asl, in early dry season of March – April, 2018. All developmental stages ofH. bradyion tea plant parts of 20 sample plants were observed and recordedin situin the morning, at noon, and in the afternoon. Results showed that nymphs dominated theH. bradyipopulation structure. Population density in the morning (06.00-08.00 a.m.) was 45.1 individuals/20 plants (5.54% eggs, 80.71% nymphs, 13.75%adults), at noon (11.00 a.m.-13.00 p.m.) was 41.7 individuals/20 plants (3.40% eggs, 84.00% nymphs, 12.60% adults), and in the afternoon was 37.0 individuals/20 plants (0% eggs, 88.38% nymphs, 11.62% adults). TheH. bradyiwas mostly present on tea shoots at upper leaf surface namely 97.08% in the morning, 79.27% at noon, and 88.14% in the afternoon, the rest was on lower leaf surface, shoot internodes, and other plant parts. The eggs were only found on tender internodes of shoots.
How to Be a Better Surgical Pathology Consultant
Authors: Zarrin-Khameh Neda
Published: March 2021

Objectives

Consultation on surgical pathology specimens is part of the daily professional practice of every pathologist. We evaluated the characteristics of a good consultant and the habits that should be avoided.

Methods

A 1-page questionnaire was prepared to evaluate how pathologists select their consultants.

Results

The questionnaire was emailed to 106 pathologists. Fifty-eight pathologists completed the questionnaire (55% response rate). The most important criteria for a consultant were knowledge and expertise. Accessibility, turnaround time, and teaching (providing explanation about the case) were selected next for choosing a consultant. The 2 factors that contributed to avoiding a consultant were expensive workup and changing the diagnosis. Open questions about “definition of best/worst consultant,” “when to change the consultant,” and “if the criteria for consultant have changed over time” provided additional valuable information.

Conclusions

Accessibility, short turnaround time, and teaching are the most important reasons for selecting a consultant. Performing an expensive workup and being in the habit of changing the diagnosis are the factors that make a consultant less favorable.
Invited Commentary: Body Mass Index and Risk of Dementia—Potential Explanations for Life-Course Differences in Risk Estimates and Future Research Directions
Authors: Brenowitz Willa D
Published: March 2021

The relationship between body mass index (BMI) and health outcomes of older adults, including dementia, remains controversial. Many studies find inverse associations between BMI and dementia among older adults, while in other studies high BMI in midlife is associated with increased dementia risk. In this issue, Li et al. (Am J Epidemiol. 2021;190(12):2503–2510) examine BMI from mid- to late life and risk of dementia using the extensive follow-up of the Framingham Offspring Study. They found changing trends in the association between BMI and dementia from a positive association for midlife (ages 40–49) to an inverse trend in late life. Their work demonstrates the importance of studying dementia risk factors across the life course. Midlife obesity might be an important modifiable risk factor for dementia. However, because incipient dementia can lead to weight loss, reverse causation remains a key source of bias that could explain an inverse trend between BMI and dementia in older ages. The extent of other biases, including unmeasured confounding, inaccuracy of BMI as a measure for adiposity, or selective survival, are also unclear. Triangulating evidence on body composition and dementia risk could lead to better targets for dementia intervention, but future work will need to evaluate specific pathways.
Association of Stress-Health Factors among Parkinson’s Disease Patient/Caregiving-Partner Dyads
Authors: Phillips Kala M , Siwik Chelsea , Rodgers Allison , Salmon Paul , Litvan Irene , Jablonski Megan E , Filoteo J Vincent , Cash Elizabeth , Sephton Sandra E
Published: March 2021

Objective

Few studies have explored the shared effects of Parkinson’s disease (PD) within patient/caregiver dyads. To fill this gap, we compared stress-health outcomes of patients with those of caregiving-partners, examined individual stress-health associations, and explored stress-health associations within dyads.

Method

A total of 18 PD patient/caregiving-partner dyads (N = 36) reported on disease-specific distress, anxiety, quality of life (QOL), and provided saliva samples for cortisol assessment. This cross-sectional, secondary analysis of a prospective pilot study used Actor-Partner Interdependence Models to test aims.

Results

Patients reported greater anxiety, poorer QOL, and demonstrated flatter cortisol slopes and higher mean bedtime cortisol compared to caregiving-partners. Both patients and caregiving-partners with greater anxiety had elevated bedtime cortisol and poorer QOL. Greater disease-specific distress in an individual was associated with higher diurnal mean cortisol in their partner.

Conclusions

Findings highlight the potential for psychosocial interventions at the dyadic level to reduce shared burden and promote coping among PD patient/caregiving-partner dyads.
INPP5K and SIL1 associated pathologies with overlapping clinical phenotypes converge through dysregulation of PHGDH
Authors: Hathazi Denisa , Cox Dan , D'Amico Adele , Tasca Giorgio , Charlton Richard , Carlier Robert-Yves , Baumann Jennifer , Kollipara Laxmikanth , Zahedi René P , Feldmann Ingo , Deleuze Jean-Francois , Torella Annalaura , Cohn Ronald , Robinson Emily , Ricci Francesco , Jungbluth Heinz , Fattori Fabiana , Boland Anne , O’Connor Emily , Horvath Rita , Barresi Rita , Lochmüller Hanns , Urtizberea Andoni , Jacquemont Marie-Line , Nelson Isabelle , Swan Laura , Bonne Gisèle , Roos Andreas
Published: March 2021

Marinesco-Sjögren syndrome is a rare human disorder caused by biallelic mutations in SIL1 characterized by cataracts in infancy, myopathy and ataxia, symptoms which are also associated with a novel disorder caused by mutations in INPP5K. While these phenotypic similarities may suggest commonalties at a molecular level, an overlapping pathomechanism has not been established yet. In this study, we present six new INPP5K patients and expand the current mutational and phenotypical spectrum of the disease showing the clinical overlap between Marinesco-Sjögren syndrome and the INPP5K phenotype. We applied unbiased proteomic profiling on cells derived from Marinesco-Sjögren syndrome and INPP5K patients and identified alterations in d-3-PHGDH as a common molecular feature. d-3-PHGDH modulates the production of l-serine and mutations in this enzyme were previously associated with a neurological phenotype, which clinically overlaps with Marinesco-Sjögren syndrome and INPP5K disease. As l-serine administration represents a promising therapeutic strategy for d-3-PHGDH patients, we tested the effect of l-serine in generated sil1, phgdh and inpp5k a+b zebrafish models, which showed an improvement in their neuronal phenotype. Thus, our study defines a core phenotypical feature underpinning a key common molecular mechanism in three rare diseases and reveals a common and novel therapeutic target for these patients.
Cation leak underlies neuronal excitability in an HCN1 developmental and epileptic encephalopathy
Authors: Bleakley Lauren E , McKenzie Chaseley E , Soh Ming S , Forster Ian C , Pinares-Garcia Paulo , Sedo Alicia , Kathirvel Anirudh , Churilov Leonid , Jancovski Nikola , Maljevic Snezana , Berkovic Samuel F , Scheffer Ingrid E , Petrou Steven , Santoro Bina , Reid Christopher A
Published: March 2021

Pathogenic variants in HCN1 are associated with developmental and epileptic encephalopathies. The recurrent de novo HCN1 M305L pathogenic variant is associated with severe developmental impairment and drug-resistant epilepsy. We engineered the homologue Hcn1 M294L heterozygous knock-in (Hcn1M294L) mouse to explore the disease mechanism underlying an HCN1 developmental and epileptic encephalopathy. The Hcn1M294L mouse recapitulated the phenotypic features of patients with the HCN1 M305L variant, including spontaneous seizures and a learning deficit. Active epileptiform spiking on the electrocorticogram and morphological markers typical of rodent seizure models were observed in the Hcn1M294L mouse. Lamotrigine exacerbated seizures and increased spiking, whereas sodium valproate reduced spiking, mirroring drug responses reported in a patient with this variant. Functional analysis in Xenopus laevis oocytes and layer V somatosensory cortical pyramidal neurons in ex vivo tissue revealed a loss of voltage dependence for the disease variant resulting in a constitutively open channel that allowed for cation ‘leak’ at depolarized membrane potentials. Consequently, Hcn1M294L layer V somatosensory cortical pyramidal neurons were significantly depolarized at rest. These neurons adapted through a depolarizing shift in action potential threshold. Despite this compensation, layer V somatosensory cortical pyramidal neurons fired action potentials more readily from rest. A similar depolarized resting potential and left-shift in rheobase was observed for CA1 hippocampal pyramidal neurons. The Hcn1M294L mouse provides insight into the pathological mechanisms underlying hyperexcitability in HCN1 developmental and epileptic encephalopathy, as well as being a preclinical model with strong construct and face validity, on which potential treatments can be tested.
A phenomapping-derived tool to personalize the selection of anatomical vs. functional testing in evaluating chest pain (ASSIST)
Authors: Oikonomou Evangelos K , Van Dijk David , Parise Helen , Suchard Marc A , de Lemos James , Antoniades Charalambos , Velazquez Eric J , Miller Edward J , Khera Rohan
Published: March 2021

Aims 

Coronary artery disease is frequently diagnosed following evaluation of stable chest pain with anatomical or functional testing. A more granular understanding of patient phenotypes that benefit from either strategy may enable personalized testing.

Methods and results 

Using participant-level data from 9572 patients undergoing anatomical (n = 4734) vs. functional (n = 4838) testing in the PROMISE (PROspective Multicenter Imaging Study for Evaluation of Chest Pain) trial, we created a topological representation of the study population based on 57 pre-randomization variables. Within each patient’s 5% topological neighbourhood, Cox regression models provided individual patient-centred hazard ratios for major adverse cardiovascular events and revealed marked heterogeneity across the phenomap [median 1.11 (10th to 90th percentile: 0.52–2.61]), suggestive of distinct phenotypic neighbourhoods favouring anatomical or functional testing. Based on this risk phenomap, we employed an extreme gradient boosting algorithm in 80% of the PROMISE population to predict the personalized benefit of anatomical vs. functional testing using 12 model-derived, routinely collected variables and created a decision support tool named ASSIST (Anatomical vs. Stress teSting decIsion Support Tool). In both the remaining 20% of PROMISE and an external validation set consisting of patients from SCOT-HEART (Scottish COmputed Tomography of the HEART Trial) undergoing anatomical-first vs. functional-first assessment, the testing strategy recommended by ASSIST was associated with a significantly lower incidence of each study's primary endpoint (P = 0.0024 and P = 0.0321 for interaction, respectively), as well as a harmonized endpoint of all-cause mortality or non-fatal myocardial infarction (P = 0.0309 and P < 0.0001 for interaction, respectively).

Conclusion 

We propose a novel phenomapping-derived decision support tool to standardize the selection of anatomical vs. functional testing in the evaluation of stable chest pain, validated in two large and geographically diverse clinical trial populations.
Appendicitis in children with acute abdominal pain in primary care, a retrospective cohort study
Authors: Blok Guus C G H , Veenstra Laura M M , van der Lei Johan , Berger Marjolein Y , Holtman Gea A
Published: March 2021

Background

General practitioners (GPs) face a diagnostic challenge when assessing acute abdominal pain in children. However, no information is available on the current diagnostic process or the diagnostic accuracy of history and physical examination in primary care settings.

Objective

To describe the diagnostic process for acute abdominal pain among children in primary care, focusing on appendicitis, and to assess the diagnostic accuracy of individual clinical features.

Methods

A retrospective cohort study in Dutch primary care, using the Integrated Primary Care Information database. Children aged 4–18 years were included if they had no history of appendicitis and presented with acute abdominal pain during 2010–2016. We evaluated GP management and the diagnostic accuracy of clinical features for appendicitis. Pre- and post-test probabilities were calculated for each clinical feature and compared with the probability of appendicitis after GP assessment.

Results

Out of 5691 children, 944 (16.6%) were referred and 291 (5.1%) had appendicitis, of whom 55 (18.9%) were initially misdiagnosed. The pre-test probability (i.e. of appendicitis in evaluated children) varied from 3% (rigidity) to 28% (migratory pain). Concerning post-test probabilities, positive values for rebound pain (32.1%) and guarding (35.8%) and the negative value for right lower quadrant tenderness (0.6%) were superior to overall GP assessment (29.6% and 1.1%, respectively).

Conclusions

GP assessment will miss almost one-fifth of children with appendicitis at their first presentation, and about two-third of GP referrals will be negative. The presence of specific signs can increase or decrease the likelihood of appendicitis, emphasising the importance of a physical examination.
Cyber offense in NATO: challenges and opportunities
Authors: Jacobsen Jeppe T
Published: March 2021

As a response to the Russian invasion of Crimea, NATO returned to the core military concepts of deterrence and collective defence. This NATO adaption has recently come to include attempts to integrate offensive cyber effects into NATO force structure and response doctrine. The article argues—counter to what is publicly declared—that such an integration does little to strengthen NATO's deterrence posture and is unlikely to deter non-military, hybrid cyber activity below the threshold of collective defence. The article identifies several practical challenges to the current integration effort, which include the temporal dimension of developing exploits, battle damage assessment and deconfliction. With these challenges in mind, the article suggests that deploying minor and less resourceful cyber effects that cause persistent ‘cyber annoyances’ holds an unappreciated potential as they can drain opponent resources, disturb vital IT-systems and complicate decision-making. The article ends by arguing that NATO should not adapt its collective defence clause to cyberspace. A more active NATO in cyberspace risks undermining the cyber-intelligence norm that so far has prevented escalation and thereby increasing the likelihood that Russia misinterprets intelligence and active cyber defence activities as military preparation, armament or an attack in the making.
The development of a sustainability assessment indicator and its response to management changes as derived from salmon lice dispersal modelling
Authors: Sandvik Anne D , Bui Samantha , Huserbråten Mats , Karlsen Ørjan , Myksvoll Mari S , Ådlandsvik Bjørn , Johnsen Ingrid A
Published: March 2021

Aquaculture is providing an increasingly larger proportion of the world’s protein for human consumption; however, its environmental impact is a bottleneck for sustainable expansion. In Norway, the government has enacted a framework where salmon lice-induced mortality in wild salmonid populations is used for assessing the environmental sustainability in production zones. Direct measurements of the level of lice-induced mortality on wild salmonids are difficult to acquire, thus comprehensive sustainability assessments are based on a set of evidence-based proxies. One such proxy is the infestation pressure from a bio-hydrodynamic model, from which we develop an index that summarize the sustainability of aquaculture in terms of lice infestation. This index is based on the proportion of areas with elevated lice loads, and is a novel approach used to investigate how sustainability could be achieved through scenario testing of different management strategies. The analyses identified a mismatch between legal and sustainable lice levels, but also a beneficial effect of reducing lice levels on farms. This study’s approach demonstrated how bio-hydrodynamic models might be used to assess sustainability and to predict the necessary reduction of lice larvae from farms to classify the entire Norwegian aquaculture industry as environmentally sustainable.
Multi-fleet state-space assessment model strengthens confidence in single-fleet SAM and provides fleet-specific forecast options
Authors: Nielsen Anders , Hintzen Niels T , Mosegaard Henrik , Trijoulet Vanessa , Berg Casper W
Published: March 2021

The state-space assessment model (SAM) is increasingly used to assess fish stocks in International Council for the Exploration of the Sea. One unique feature of the SAM class is that it allows the fishing selectivity to vary over time, and the degree to which it varies is not subjectively assigned, but estimated within the model. Selection may vary over time due to changes in the spatial pattern of the fish stock or fishing fleet, but a direct cause of selectivity change can be changed in fishing technology or other measures that target specific segments of the fish stocks. If the relative catches from fishing fleets which target different age or size classes of a species are changing over time, then the overall selectivity will also change—even if the selectivity within each fleet is fairly constant. A recent extension of the SAM model allows multiple fleets to be defined. It has been applied to two herring stocks to allow more detailed and fleet-specific management options in forecasts. For both stocks, the assessment from the multi-fleet models was consistent with the results from the single-fleet models, which strengthens confidence in the estimated time-varying selectivity for these and other stocks.
H∞ Optimal control of jump systems over multiple lossy communication channels
Authors: Mazumdar Abhijit , Krishnaswamy Srinivasan , Majhi Somanath
Published: March 2021

In this paper, the $H_{\infty }$ optimal control problem for a Markovian jump linear system (MJLS) over multiple lossy communication channels is considered. It is assumed that the controller communicates with each actuator through a different communication channel. We solve the $H_{\infty }$ optimization problem for the system with a Transmission Control Protocol (TCP) using the theory of dynamic games and obtain a state feedback controller. The infinite horizon $H_{\infty }$ optimization problem is analysed as a limiting case of the finite horizon optimization problem. Then, we obtain the corresponding state feedback controller and show that it stabilizes the closed-loop system in the face of random packet dropouts. A novel and relaxed condition for stability of the closed-loop system with the saddle-point policy is also presented. Further, we show that a weaker notion of observability is sufficient to establish our results.
Lipoblastoma as a cause of secondary omental torsion in children: report of the first case
Authors: Boscarelli Alessandro , Guida Edoardo , Ceschiutti Giulia , Bossini Benedetta , Olenik Damiana , Barbi Egidio , Schleef Jürgen
Published: March 2021

Acute abdominal pain remains a major diagnostic challenge to date. Omental torsion is an infrequent cause of abdominal pain in children, which usually presents with non-specific symptoms. Herein, we report a case of persistent abdominal pain after a minor abdominal trauma. A solid mass was found in the lower abdomen at ultrasound imaging evaluation. Surgical exploration demonstrated an omental torsion secondary to a rare neoplasm of childhood.
Super-eddington emission from accreting, highly magnetized neutron stars with a multipolar magnetic field
Authors: Brice Nabil , Zane Silvia , Turolla Roberto , Wu Kinwah
Published: March 2021

Pulsating ultraluminous X-ray sources (PULXs) are characterized by an extremely large luminosity (>1040 erg s−1). While there is a general consensus that they host an accreting, magnetized neutron star (NS), the problem of how to produce luminosities >100 times the Eddington limit, LE, of a solar mass object is still debated. A promising explanation relies on the reduction of the opacities in the presence of a strong magnetic field, which allows for the local flux to be much larger than the Eddington flux. However, avoiding the onset of the propeller effect may be a serious problem. Here, we reconsider the problem of column accretion on to a highly magnetized NS, extending previously published calculations by relaxing the assumption of a pure dipolar field and allowing for more complex magnetic field topologies. We find that the maximum luminosity is determined primarily by the magnetic field strength near the NS surface. We also investigate other factors determining the accretion column geometry and the emergent luminosity, such as the assumptions on the parameters governing the accretion flow at the disc–magnetosphere boundary. We conclude that a strongly magnetized NS with a dipole component of ∼1013 G, octupole component of ∼1014 G, and spin period ∼1 s can produce a luminosity of ∼1041 erg s−1 while avoiding the propeller regime. We apply our model to two PULXs, NGC 5907 ULX-1, and NGC 7793 P13, and discuss how their luminosity and spin period rate can be explained in terms of different configurations, either with or without multipolar magnetic components.
Electron-impact rotational excitation cross-sections and rate coefficients of molecular ion: HCO+
Authors: Singh Jasmeet
Published: March 2021

HCO+ is one of the most abundant polyatomic ion in the Universe, also its presence in the planetary atmospheres and interstellar medium (ISM) makes it an interesting case to study. Low energy e−-HCO+ collisions result in rotational excitation and other molecular processes. In this study, the cross-sections for rotational transitions in HCO+ are evaluated for four rotational levels (j = 0, 1, 2, and 3) using the UK R-matrix method and the multichannel quantum defect theory (MQDT). The UK R-matrix method used to generate scattering matrices, through which cross-sections are computed. In past two decades, after developments and implementations of different theoretical approaches, the improved channel elimination procedure applied here is more promising to evaluate more accurate results near rotational thresholds important for the analysis of intensities of microwave region in plasma modelling. The rate coefficients are deduced from the computed cross-sections and studied over a wide electron temperature range.
Rare instances of haploid inducer DNA in potato dihaploids and ploidy-dependent genome instability
Authors: Amundson Kirk R. , Ordoñez Benny , Santayana Monica , Nganga Mwaura Livingstone , Henry Isabelle M. , Bonierbale Merideth , Khan Awais , Tan Ek Han , Comai Luca
Published: March 2021

In cultivated tetraploid potato (Solanum tuberosum), reduction to diploidy (dihaploidy) allows for hybridization to diploids and introgression breeding and may facilitate the production of inbreds. Pollination with haploid inducers (HIs) yields maternal dihaploids, as well as triploid and tetraploid hybrids. Dihaploids may result from parthenogenesis, entailing the development of embryos from unfertilized eggs, or genome elimination, entailing missegregation and the loss of paternal chromosomes. A sign of genome elimination is the occasional persistence of HI DNA in some dihaploids. We characterized the genomes of 919 putative dihaploids and 134 hybrids produced by pollinating tetraploid clones with three HIs: IVP35, IVP101, and PL-4. Whole-chromosome or segmental aneuploidy was observed in 76 dihaploids, with karyotypes ranging from 2n = 2x − 1 = 23 to 2n = 2x + 3 = 27. Of the additional chromosomes in 74 aneuploids, 66 were from the non-inducer parent and 8 from the inducer parent. Overall, we detected full or partial chromosomes from the HI parent in 0.87% of the dihaploids, irrespective of parental genotypes. Chromosomal breaks commonly affected the paternal genome in the dihaploid and tetraploid progeny, but not in the triploid progeny, correlating instability to sperm ploidy and to haploid induction. The residual HI DNA discovered in the progeny is consistent with genome elimination as the mechanism of haploid induction.
Stabilization Exercises Versus Flexion Exercises in Degenerative Spondylolisthesis: A Randomized Controlled Trial
Authors: Nava-Bringas Tania Inés , Romero-Fierro Lizbeth Olivia , Trani-Chagoya Yessica Patricia , Macías-Hernández Salvador Israel , García-Guerrero Eduardo , Hernández-López Mario , Roberto Coronado-Zarco
Published: March 2021

Objective

Exercise is the mainstay of treatment in individuals with low back pain and the first-line option in degenerative spondylolisthesis (DS); however, there is still no consensus surrounding the superiority of any specific exercise program. Thus, the primary aim of this study was to compare the effectiveness of lumbar stabilization exercises and flexion exercises for pain control and improvements of disability in individuals with chronic low back pain (CLBP) and DS.

Methods

A randomized controlled trial was conducted in a tertiary public hospital and included 92 individuals over the age of 50 years who were randomly allocated to lumbar stabilization exercises or flexion exercises. Participants received 6 sessions of physical therapy (monthly appointments) and were instructed to execute exercises daily at home during the 6 months of the study. The primary outcome (measured at baseline, 1 month, 3 months, and 6 months) was pain intensity (visual analog scale, 0–100 mm) and disability (Oswestry Disability Index, from 0% to 100%). Secondary outcomes were disability (Roland-Morris Disability Questionnaire, from 0 to 24 points), changes in body mass index, and flexibility (fingertip to floor, in centimeters) at baseline and 6 months, and also the total of days of analgesic use at 6-month follow-up.

Results

Mean differences between groups were not significant (for lumbar pain: 0.56 [95% CI = −11.48 to 12.61]; for radicular pain: −1.23 [95% CI = −14.11 to 11.64]; for Oswestry Disability Index: −0.61 [95% CI = −6.92 to 5.69]; for Roland-Morris Disability Questionnaire: 0.53 [95% CI = −1.69 to 2.76]).

Conclusion

The findings from the present study reveal that flexion exercises are not inferior to and offer a similar response to stabilization exercises for the control of pain and improvements of disability in individuals with CLBP and DS.

Impact

Exercise is the mainstay of treatment in individuals with CLBP and DS; however, there is still no consensus surrounding the superiority of any specific exercise program. This study finds that flexion exercises are not inferior to and offer a similar response to stabilization exercises.

Lay Summary

Exercise is the mainstay of treatment in individuals with CLBP and DS, but there is no consensus on the superiority of any specific exercise program. If you have DS, flexion exercises may provide similar effects to stabilization exercises.
Early Tocilizumab Dosing Is Associated With Improved Survival in Critically Ill Patients Infected With Severe Acute Respiratory Syndrome Coronavirus-2
Authors: Petrak Russell M. , Van Hise Nicholas W. , Skorodin Nathan C. , Fliegelman Robert M. , Chundi Vishnu , Didwania Vishal , Han Alice , Harting Brian P. , Hines David W.
Published: March 2021

Objectives:

To identify the most efficacious timing for tocilizumab administration in critically ill patients infected with severe acute respiratory syndrome coronavirus-2.

Design:

Observational multicenter cohort study.

Setting:

A total of 23 acute care hospitals in four states.

Patients:

One-hundred eighteen patients admitted between March 13, 2020, and April 16, 2020. Eighty-one patients received tocilizumab, and 37 were untreated and served as a control group.

Measurements and Main Results:

The main outcome was mortality and was analyzed by timing of tocilizumab dosing. Early dosing was defined as a tocilizumab dose administered prior to or within 1 day of intubation. Late dosing was defined as a dose administered greater than 1 day after intubation. A control group that was treated only with standard of care, and without tocilizumab, was used for comparison. Early tocilizumab therapy was associated with a statistically significant decrease in mortality as compared to patients who were untreated (p = 0.003). Dosing tocilizumab late was associated with an increased mortality compared with the untreated group (p = 0.006).

Conclusions:

Early tocilizumab administration was associated with decreased mortality in critically ill severe acute respiratory syndrome coronavirus-2 patients, but a potential detriment was suggested by dosing later in a patient’s course.
Patient-Level Barriers and Facilitators to Early Mobilization and the Relationship With Physical Disability Post–Intensive Care
Authors: Potter Kelly , Miller Sarah , Newman Susan
Published: March 2021

Background

Early mobilization (EM) is associated with reduced physical disability post–intensive care (PD PIC). Yet, contextual factors facilitate or impede delivery of EM in the intensive care unit (ICU). Only 45% of ICUs in the United States routinely practice EM despite its recognized benefits.

Objectives

To analyze the evidence on the relationship between critical care EM, PD PIC, and personal (patient-level) factors, using the theoretical lens of the World Health Organization's International Classification of Functioning, Disability, and Health (ICF).

Method

The Whittemore and Knafl methodology for integrative reviews and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) reporting guidelines were followed. Qualitative, quantitative, and mixed-methods studies (n = 38) that evaluated EM and 1 or more domains of the World Health Organization ICF were included. Quality was appraised using the Mixed-Methods Appraisal Tool. Study characteristics were evaluated for common themes and relationships. The ICF domains and subdomains pertaining to each study were synthesized.

Results

Early mobilization delivery was influenced by personal factors. Deeper sedation level, the presence of delirium, higher patient acuity, the presence of medical devices, and patient weight were identified barriers to EM delivery. Patient engagement in EM was associated with improved delivery. Patients who enjoyed rehabilitation were more likely to demonstrate improvement in functional impairment than those who did not enjoy rehabilitation.

Discussion

Early mobilization is associated with reduced PD PIC, yet numerous contextual factors affect the delivery of EM in the ICU. Further study of patient-level factors and EM must explore the relationship between patient engagement, baseline demographics, and functional status at ICU admission, patient-level considerations for decisions to mobilize, and EM in the ICU. This research is critical to improving the delivery of EM in the ICU and reducing PD PIC.
Health Care Professional Students’ Perceptions of Teamwork and Roles After an Interprofessional Critical Care Simulation
Authors: Davis Jenna , Zulkosky Kristen , Ruth-Sahd Lisa A. , Frank Eva M. , Dommel Lynne , Minchhoff Dolores , Uhrich Karen
Published: March 2021

Background

Educational opportunities for health care professional students to learn collaborative communication and the roles and responsibilities of other disciplines are minimal unless faculty are intentional about facilitating this interdisciplinary learning.

Objectives

The aim of this study was to determine how a simulation-enhanced interprofessional education (Sim-IPE) teaching strategy fostered communication and interdisciplinary awareness between students from multiple disciplines.

Method

This pretest-posttest design surveyed undergraduate students from 5 disciplines. The Student Perceptions of Interprofessional Clinical Education-Revised tool examined students' perceptions of teamwork and roles after an in-depth, multistate critical care simulation experience.

Results

All students' perceptions of teamwork increased after the Sim-IPE. More experience in the health care field is associated with an increased perception of teamwork and roles/responsibilities.

Discussion

On the basis of these findings, the critical care Sim-IPE was an effective teaching strategy to increase the perception of roles and responsibilities of interprofessional critical care team members with applicability to many other specialty topics.
Critical Incidents Involving the Medical Emergency Team
Authors: Danielis Matteo , Destrebecq Anne , Terzoni Stefano , Palese Alvisa
Published: March 2021

Background

Medical emergency teams (METs), which have been established in several countries, contribute to a reported decrease in deteriorated patients' in-hospital mortality. To date, no data have been published on critical incidents that occurred in METs affecting patients' safety.

Objectives

The aim of the study was to identify and describe critical incidents that occurred during METs' activities in a large academic Italian hospital.

Methods

The data, which were stored in the official incident reporting system of the hospital and included all critical incidents that occurred and were reported in anonymous and voluntary forms over a 5-year period, were retrospectively analyzed.

Results

Overall, 17 critical incidents emerged, during both the team alert stage (n = 10) and its performance (n = 7), with approximately 3 events per year and an incident rate of 1.7 for every 1000 MET interventions.

Discussion

Medical emergency teams' critical incidents are rare and mainly due to the lack of compliance with protocols and of training and supplies, which require appropriate educational and organizational strategies.
Malignant transformation arising from mature ovarian cystic teratoma
Authors: Qin Li , Zhao Tao , Liu Xin , Wang Hongli , Gu Xin , Chen Dian , Wang Zaiping , He Du
Published: March 2021

Malignant transformation arising in mature cystic teratoma (MT-MCT) is a rare neoplasm of the ovary. Herein, we aimed to evaluate the clinicopathological features and treatment outcome of the Han Chinese women with MT-MCT.

In this retrospective study, the clinical data of patients who had been surgically treated from January 2000 to November 2019 and in whom the diagnosis of MCT was confirmed based on the pathology were included. Fourteen patients with MT-MCT from a total of 569 cases (2.46% incidence) of MCT were reviewed.

The mean age of patients with MT-MCT was 51.3 (range, 31–71) years, while the mean age of patients with MCT was 45.3 (range, 17–62) years. Upon gross examination, the mean size of MT-MCT was 14.0 (range, 11–25) cm, whereas the mean size of MCT was 7.5 (range, 4–10) cm. Primary surgical staging was performed in all cases. Complete cytoreduction and suboptimal surgical resection were performed in 12 (85.7%) and 2 (14.3%) cases, respectively. Thirteen patients with malignant transformation of squamous cell carcinoma (SCC) whose Federation International of Gynecology and Obstetrics stage was >1 received chemotherapy, comprising carboplatin and paclitaxel. Response to the chemotherapy regimen was complete in 12 patients; 1/12 patients died within the median follow-up period of 16.5 months. The 5-year overall survival rate and disease-free survival rates were 31.2% and 31.6%, respectively.

From the data generated, we conclude that the rate of MT-MCT increases with age. The MT-MCT was much higher in women of postmenopausal age than in younger women. We described our experience of successfully treating patients with malignant transformation of SCC with primary surgical staging and adjuvant chemotherapy (cisplatin, paclitaxel, bleomycin, and etoposide) that might improve survival in patients with advanced-stage disease.
Effect of Taijiquan assisted rehabilitation for breast cancer patients
Authors: Zhao Sihua , Lian Rongna , Zhang Ruinian , Wang Fanghong , Chen Hao , Wan Run
Published: March 2021

Background:

Taijiquan, as a supplementary and alternative method, has attracted more and more attention in the treatment of breast cancer. But up to now, no systematic review has been performed to evaluate the efficacy of Taijiquan in the treatment of breast cancer. In this study, Cochrane systematic review method will be used to evaluate the effect of Taijiquan in the rehabilitation process of breast cancer patients after treatment.

Methods:

PubMed, Embase. com, the Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang, and SinoMed will be searched to identify relevant studies up to May 31, 2021. We will include randomized controlled trials (RCTs) of the application of Taijiquan in post-treatment breast cancer patients. We will use the Cochrane bias risk assessment tool to assess the quality of included RCTs. We will use Stata 13.0 to perform pairwise meta-analyses using the inverse variance method. Subgroup analyses and sensitivity analyses will be conducted to investigate the sources of heterogeneity.

Results:

The results of this study will be published in a peer-reviewed journal.

Conclusion:

This study will comprehensively evaluate the efficacy of Taijiquan in the rehabilitation treatment of breast cancer. The results of this study will provide high-quality evidence to support clinical practice and guidelines development.
Accurate measurement of colorectal polyps using computer-aided analysis
Authors: Su Ruizhang , Liu Jie , Wu Bifang , Xie Yun , Zhang Yi , Zhang Wen , Zhang Yongxiu , Wan Man , Tian Zhaoxu , Hu Yiqun
Published: March 2021

Introduction

As we know, the majority of colorectal cancers are thought to evolve from colorectal adenomas. In this study, we explored the use of Computer-aided diagnosis (CAD) in the detection of colorectal polyps and the estimation of their sizes, which is important for the diagnosis and management of colorectal cancer.

Materials and methods

As the distance between colonoscopy and lesion increases, magnification tends to decrease. Therefore, the size of colorectal polyps can be calculated by taking into account the captured image and the shooting distance. In this study, the fitting curve of the magnification of electronic colonoscopy was obtained by simulating intestinal tract and polyps in vitro. Then, the distance was artificially controlled in the endoscopic operation, and the image was taken at a preset distance. The CAD system was then trained on the overall shape of colorectal polyps. Image segmentation was employed to accurately identify colorectal polyps. Finally, on the basis of the magnification factor, the real value of polyps was predicted from the shooting distance and the segmentation image size.

Results

The CAD system can automatically calculate the range of colorectal polyps and calculate the true size of the colorectal polyps according to the magnification of the corresponding distance.

Conclusions

In this study, we developed a method of accurately estimating the size of colorectal polyps. This approach is compatible with many devices, which would expand its range of applications. This method has the potential for application in other areas of clinical diagnosis.