bluuebunny/crossref_metadata_2025_split huggingface dataset:
Neuromuscular junction instability and altered intracellular calcium handling as early determinants of force loss during unloading in humans
Authors: Monti Elena , Reggiani Carlo , Franchi Martino V. , Toniolo Luana , Sandri Marco , Armani Andrea , Zampieri Sandra , Giacomello Emiliana , Sarto Fabio , Sirago Giuseppe , Murgia Marta , Nogara Leonardo , Marcucci Lorenzo , Ciciliot Stefano , Šimunic Boštjan , Pišot Rado , Narici Marco V. 
Published: April 2021

Key points
Few days of unloading are sufficient to induce a decline of skeletal muscle mass and function; notably, contractile force is lost at a faster rate than muscle mass.
The reasons behind this disproportionate loss of muscle force are still poorly understood.
We provide strong evidence of two mechanisms only hypothesized until now for the rapid muscle force loss in only 10 days of bed rest.
Our results show that an initial neuromuscular junction instability, accompanied by alterations in the innervation status and impairment of single fibre sarcoplasmic reticulum function contribute to the loss of contractile force in front of a preserved myofibrillar function and central activation capacity.
Early onset of neuromuscular junction instability and impairment in calcium dynamics involved in excitation–contraction coupling are proposed as eligible determinants to the greater decline in muscle force than in muscle size during unloading.
AbstractUnloading induces rapid skeletal muscle atrophy and functional decline. Importantly, force is lost at a much higher rate than muscle mass. We aimed to investigate the early determinants of the disproportionate loss of force compared to that of muscle mass in response to unloading. Ten young participants underwent 10 days of bed rest (BR). At baseline (BR0) and at 10 days (BR10), quadriceps femoris (QF) volume (VOL) and isometric maximum voluntary contraction (MVC) were assessed. At BR0 and BR10 blood samples and biopsies of vastus lateralis (VL) muscle were collected. Neuromuscular junction (NMJ) stability and myofibre innervation status were assessed, together with single fibre mechanical properties and sarcoplasmic reticulum (SR) calcium handling. From BR0 to BR10, QFVOL and MVC decreased by 5.2% (P = 0.003) and 14.3% (P < 0.001), respectively. Initial and partial denervation was detected from increased neural cell adhesion molecule (NCAM)‐positive myofibres at BR10 compared with BR0 (+3.4%, P = 0.016). NMJ instability was further inferred from increased C‐terminal agrin fragment concentration in serum (+19.2% at BR10, P = 0.031). Fast fibre cross‐sectional area (CSA) showed a trend to decrease by 15% (P = 0.055) at BR10, while single fibre maximal tension (force/CSA) was unchanged. However, at BR10 SR Ca2+ release in response to caffeine decreased by 35.1% (P < 0.002) and 30.2% (P < 0.001) in fast and slow fibres, respectively, pointing to an impaired excitation–contraction coupling. These findings support the view that the early onset of NMJ instability and impairment in SR function are eligible mechanisms contributing to the greater decline in muscle force than in muscle size during unloading.
Jacobi Stability of Simple Chaotic Systems with One Lyapunov Stable Equilibrium
Authors: Li Changzhi , Chen Biyu , Liu Aimin , Tian Huanhuan 
Published: April 2021

Abstract
This paper presents Jacobi stability analysis of 23 simple chaotic systems with only one Lyapunov stable equilibrium by Kosambi-Cartan-Chern (KCC) theory, and analyzes the chaotic behavior of these systems from the geometric viewpoint. Different from Lyapunov stability, the unique equilibrium for each system is always Jacobi unstable. Moreover, the dynamical behaviors of deviation vector near equilibrium are discussed to reveal the onset of chaos for these 23 systems, and show furtherly the coexistence of unique Lyapunov stable equilibrium and chaotic attractor for each system geometrically. The obtaining results show that these chaotic systems are not robust to small perturbations of the equilibrium, indicating that the systems are extremely sensitive to internal environment. This reveals that the chaotic flows generated by these systems may be related to Jacobi instability of the equilibrium. It is hoped that the study of this paper can help reveal the true geometrical structure of hidden chaotic attractors.
Phased Array Ultrasonic Testing of Inconel 625 Produced by Selective Laser Melting
Authors: Allam Ahmed , Sugino Christopher , Harding Matthew , Bishop D. Paul , Erturk Alper , Ruzzene Massimo 
Published: April 2021

Abstract
We investigate the use of phased array ultrasonic testing (PAUT) as an offsite non-destructive quality assurance technique for parts made by selective laser melting (SLM). SLM is a popular additive manufacturing (AM) approach for fabricating high-value metallic components with complex geometries. Slight variations in the laser power during fabrication might lead to internal defect development within the part, which could compromise its mechanical strength and fatigue life. PAUT is employed to detect typical internal porosity generated in Inconel 625 samples due to laser power fluctuation during SLM. The typical defect size, shape, and distribution are first identified using metallography and X-ray computed tomography (XCT). B-Scan images of the defect region is then generated experimentally using a 5-MHz linear UT phased array probe. Finite elements simulate wave propagation using geometries obtained from XCT images. The simulation results are compared to the experimental imaging of large defect regions and then used to generate total focusing method images of isolated clusters of 50–200 μm defects. The testing technique illustrates a successful application of PAUT for quality inspection of SLM parts.
Effect of Utilizing a Novel Intake Manifold Design on Smoke Emissions and Particulate Size Distributions of a Gas-to-Liquid Diesel Engine
Authors: Elbashir Aboubaker M. , Saker Ahmad T. , Ahmed Samer F. 
Published: April 2021

Abstract
Smoke emissions and particulate matter (PM) size distributions were investigated on a direct-injection (DI) single-cylinder diesel engine running on both gas-to-liquid (GTL) and diesel fuels utilizing a novel spiral-helical intake manifold design. Smoke opacity was measured at a wide range of engine loads and speeds with both fuels to examine the effect of using the new manifold on smoke emissions. In addition, total PM numbers of fine particles (PM diameter ≤ 1.0 μm) and coarse particles (˃1.0 μm) were quantified with both fuels. Moreover, high-resolution transmission electron microscopy (HRTEM) images were taken with different resolutions to observe the PM sizes produced from each fuel when using the new and normal manifolds. The results showed that using the novel manifold reduced smoke emissions for both GTL and diesel fuels with about 36% at low loads and 7% at high loads. However, using the new manifold with GTL fuel showed superior performance to reduce smoke with about 60% at low loads and 10% at high loads. For the PM size distribution, the new manifold reduced total PM emissions in general. However, significant reductions were obtained with fine PM sizes (0.3–1.0 μm) when GTL fuel was used with about 30% for constant load tests, and about 40% for constant speed tests. On the other hand, the new manifold tended to increase slightly the coarse PM sizes. The HRTEM images of the PM structure for both manifolds and fuels have confirmed the above results.
The Use of Constraint Management Techniques in the Generalized Reduced Gradient Method
Authors: Agrawal Rajiv , Cheng Junhua , Kinzel Gary L. 
Published: April 2021

Abstract
The Generalized Reduced Gradient (GRG) method has proven to be an effective strategy for solving constrained nonlinear programming problems, and this paper proposes the use of constraint management techniques to enhance the GRG method. Some of the troublesome issues in the method such as the selection of the initial basis and the problem of basis interchange can be resolved if the constraints are represented in the form of a nonlinear occurrence matrix. A heuristic algorithm is presented to determine an initial partition of the state and decision variables. The procedure is aimed at minimizing the nonlinear component in the set of state variables so that computational effort during the numerical iterations is reduced. Another algorithm is presented to automate the basis interchange by using a linearized model of the governing equations and a backward dependency procedure. An improved canonical form for the general nonlinear programming problem that has the objective function embedded in the set of equality constraints is also presented. Constraint management ideas are also used to decompose the basis Jacobian matrix into smaller irreducible subsets. Several mathematical and design problems are posed as test cases for the Constraint Management Based Generalized Reduced Gradient (CMB-GRG) procedure, and representative results are presented.
Optimum Reinforcement of Damaged Structures Using a Homogenization Method
Authors: Soto Ciro A. , Díaz Alejandro R. , Kikuchi Noboru 
Published: April 2021

Abstract
A new application of a homogenization method in optimal shape design is presented. Optimum reinforcement of damaged structures is achieved by a simple modification of the approach presented by Bendsøe and Kikuchi [1] for optimum structural shape synthesis. The method is applied to frame structures subject to specific damages.
Early Cenozoic partial melting of meta-sedimentary rocks of the eastern Gangdese arc, southern Tibet, and its contribution to syn-collisional magmatism
Authors: Jiang Yuan-Yuan , Zhang Ze-Ming , Palin Richard M. , Ding Hui-Xia , Mo Xuan-Xue 
Published: April 2021

AbstractContinental magmatic arcs are characterized by the accretion of voluminous mantle-derived magmatic rocks and the growth of juvenile crust. However, significant volumes of meta-sedimentary rocks occur in the middle and lower arc crust, and the contributions of these rocks to the evolution of arc crust remain unclear. In this paper, we conduct a systematic study of petrology, geochronology, and geochemistry of migmatitic paragneisses from the eastern Gangdese magmatic arc, southern Tibet. The results show that the paragneisses were derived from late Carboniferous greywacke, and underwent an early Cenozoic (69–41 Ma) upper amphibolite-facies metamorphism and partial melting at pressure-temperature conditions of ~11 kbar and ~740 °C, and generated granitic melts with enriched Hf isotopic compositions (anatectic zircon εHf(t) = −10.57 to +0.78). Combined with the existing results, we conclude that the widely distributed meta-sedimentary rocks in the eastern Gangdese arc deep crust have the same protolith ages of late Carboniferous, and record northwestward-decreasing metamorphic conditions. We consider that the deeply buried sedimentary rocks resulted in the compositional change of juvenile lower crust from mafic to felsic and the formation of syn-collisional S-type granitoids. The mixing of melts derived from mantle, juvenile lower crust, and ancient crustal materials resulted in the isotopic enrichment of the syn-collisional arc-type magmatic rocks of the Gangdese arc. We suggest that crustal shortening and underthrusting, and the accretion of mantle-derived magma during the Indo-Asian collision transported the supracrustal rocks to the deep crust of the Gangdese arc.
Optimal outcome measures for a trial of not routinely measuring gastric residual
volume in neonatal care: a mixed methods consensus process
Authors: Gale Chris , Dorling Jon , Arch Barbara , Woolfall Kerry , Deja Elizabeth , Roper Louise , Jones Ashley P , Latten Lynne , Eccleson Helen , Hickey Helen , Pathan Nazima , Preston Jennifer , Beissel Anne , Andrzejewska Izabela , Valla Frederic , Tume Lyvonne 
Published: April 2021

Background
Routine measurement of gastric residual volume to guide feeding is widespread in
neonatal units but not supported by high-quality evidence. Outcome selection is
critical to trial design.

Objective
To determine optimal outcome measures for a trial of not routinely measuring
gastric residual volume in neonatal care.

Design
A focused literature review, parent interviews, modified two-round Delphi survey
and stakeholder consensus meeting.

Participants
Sixty-one neonatal healthcare professionals participated in an eDelphi survey;
17 parents were interviewed. 19 parents and neonatal healthcare professionals took
part in the consensus meeting.

Results
Literature review generated 14 outcomes, and parent interviews contributed eight
additional outcomes; these 22 outcomes were then ranked by 74 healthcare professionals
in the first Delphi round where four further outcomes were proposed; 26 outcomes were
ranked in the second round by 61 healthcare professionals. Five outcomes were
categorised as ‘consensus in’, and no outcomes were voted ‘consensus out’. ‘No
consensus’ outcomes were discussed and voted on in a face-to-face meeting by 19
participants, where four were voted ‘consensus in’. The final nine consensus outcomes
were: mortality, necrotising enterocolitis, time to full enteral feeds, duration of
parenteral nutrition, time feeds stopped per 24 hours, healthcare-associated
infection; catheter-associated bloodstream infection, change in weight between birth
and neonatal discharge and pneumonia due to milk aspiration.

Conclusions and relevance
We have identified outcomes for a trial of no routine measurement of gastric
residual volume to guide feeding in neonatal care. This outcome set will ensure
outcomes are important to healthcare professionals and parents.
Periconception glycemic control and congenital anomalies in women with pregestational diabetes
Authors: Dude Annie M , Badreldin Nevert , Schieler Amanda , Yee Lynn M 
Published: April 2021

IntroductionTo assess the relationship between periconception glycemic control and congenital anomalies in a contemporary, diverse population of women with pregestational diabetes.Research design and methodsThis is a retrospective cohort study of all pregnant women with pregestational diabetes at a single institution (2003–2017) in the USA. The primary outcome was frequency of major or minor congenital anomalies. Glycemic control was assessed by periconception glycosylated hemoglobin (HbA1c). The association of periconception HbA1c with pregnancy outcomes was assessed using bivariable and multivariable analyses.ResultsOur sample included 351 women, of which 63.8% had type 2 diabetes. Our study cohort is racially and ethnically diverse, with approximately equal numbers of women identifying as white non-Hispanic, black non-Hispanic and Hispanic, with 3.4% identifying as Asian. Of these 351 women, 52 (14.8%) had a fetus with a congenital anomaly, of whom the majority (n=43) had a major anomaly. Over half (51.1%) of all major anomalies were cardiovascular. Compared with the group with the best glycemic control (HbA1c ≤7.4%), which had an anomaly frequency of 10.2%, the frequency of congenital anomalies increased significantly with each category of worsening glycemic control (HbA1c 7.5%–9.4%: 20.6%, adjusted OR (aOR) 2.35, 95% confidence interval (CI) 1.08 to 5.13; HbA1c 9.5% to 11.4%: 25.8%, aOR 2.86, 95% CI 1.08 to 7.59; HbA1c ≥11.5%: 37.5%, aOR 7.66, 95% CI 2.27 to 25.9).ConclusionIn a diverse cohort of women with pregestational diabetes, higher periconception HbA1c, especially HbA1c >9.5, was significantly associated with major congenital fetal anomalies. Our study sample is reflective of the current population of pregnant women with diabetes, including women with type 2 diabetes and from racial and ethnic minorities.
Evaluation of CogSport for acute concussion diagnosis in cricket
Authors: James Kira , Saw Anna E , Saw Richard , Kountouris Alex , Orchard John William 
Published: April 2021

ObjectiveThe diagnosis of sport-related concussion is a challenge for practitioners given the variable presentation and lack of a universal clinical indicator. The aim of this study was to describe the CogSport findings associated with concussion in elite Australian cricket players, and to evaluate the diagnostic ability of CogSport for this cohort.MethodsA retrospective study design was used to evaluate CogSport performance of 45 concussed (male n=27, mean age 24.5±4.5 years; female n=18, 23.5±3.5 years) compared with 45 matched non-concussed (male n=27, mean age 27.3±4.5 years; female n=18, 24.1±4.5 years) elite Australian cricket players who sustained a head impact during cricket specific activity between July 2015 and December 2019.ResultsMedian number of reported symptoms on the day of injury for concussed players was 7 out of 24, with a median symptom severity of 10 out of 120. CogSport performance deteriorated significantly in concussed cricket players’ Detection speed (p<0.001), Identification speed (p<0.001), One Back speed (p=0.001) and One Back accuracy (p=0.022) components. These components, when considered independently and together, had good diagnostic utility.ConclusionThis study demonstrated good clinical utility of CogSport for identifying concussed cricket players, particularly symptoms and Detection, Identification and One Back components. Therefore, CogSport may be considered a useful tool to assist concussion diagnosis in this cohort, and the clinician may place greater weight on the components associated with concussion diagnosis.
Pathologists’ assistants, an essential healthcare workforce: the experience of a surgical pathology department in Italy
Authors: Bortesi Mara , Marchetti Marialisa , Arpaia Ilaria , Marchi Letizia , Ganassi Marilena , Zanetti Eleonora , Fontanesi Cristina , Costantini Massimo , Piana Simonetta 
Published: April 2021

AimsThe progressive increase of both the workload and the complexity of laboratory procedures, along with shortage of staff, has made evident the need to increase the efficiency in the pathology departments. To support the pathologists, a new technical professional role, the pathologists’ assistant (PA), has been introduced.MethodsWe decided to carry out a retrospective analysis on PAs’ performance. This was compared with that of junior/senior pathologists in the amount and type of surgical specimens examined, the number of lymph node retrieved in colorectal resections, the number of cases needing a second grossing procedure and the average time spent in grossing. As the COVID-19 pandemic period in fact resulted in a dramatic reduction of histological cases in our department, we divided PA activities into two periods, according to the COVID-19 pandemic.Results‘Simple’ specimens made up the majority (92%) of the specimens examined by PAs in pre-COVID-19 period while ‘complex’ specimens, often neoplastic, represented the minor part (7%). However, ‘simple’ specimens dropped to 81% and ‘complex’ specimens rose to 18% in the COVID-19 period, when PAs had the chance to test themselves with more complicated surgical samples, under the supervision of a pathologist. Lymph node retrieval rate and average time spent in grossing are in line with literature data and confirm that PAs performance is comparable with pathologists’ one, in selected settings.ConclusionIn our experience, PA has represented a fundamental time-saving resource for the pathologists, who can devote time almost exclusively to diagnostic reporting.
Early atypical signs and insula hypometabolism predict survival in multiple system atrophy
Authors: Grimaldi Stephan , Boucekine Mohamed , Witjas Tatiana , Fluchere Frederique , Azulay Jean-Philippe , Guedj Eric , Eusebio Alexandre 
Published: April 2021

ObjectiveWe aim to search for predictors of survival among clinical and brain 18F-FDG positron emission tomography (PET) metabolic features in our cohort of patients with multiple system atrophy (MSA).MethodsWe included patients with a ‘probable’ MSA diagnosis for whom a clinical evaluation and a brain PET were performed early in the course of the disease (median 3 years, IQR 2–5). A retrospective analysis was conducted using standardised data collection. Brain PET metabolism was characterised using the Automated Anatomical Labelling Atlas. A Cox model was applied to look for factors influencing survival. Kaplan-Meier method estimated the survival rate. We proposed to develop a predictive ‘risk score’, categorised into low-risk and high-risk groups, using significant variables entered in multivariate Cox regression analysis.ResultsEighty-five patients were included. The overall median survival was 8 years (CI 6.64 to 9.36). Poor prognostic factors were orthostatic hypotension (HR=6.04 (CI 1.58 to 23.12), p=0.009), stridor (HR=3.41 (CI 1.31 to 8.87), p=0.012) and glucose PET hypometabolism in the left insula (HR=0.78 (CI 0.66 to 0.92), p=0.004). Good prognostic factors were time to diagnosis (HR=0.68 (CI 0.54 to 0.86), p=0.001) and use of selective serotonin reuptake inhibitor (SSRI) (HR=0.17 (CI 0.06 to 0.46), p<0.001). The risk score revealed a 5-year gap separating the median survival of the two groups obtained (5 years vs 10 years; HR=5.82 (CI 2.94 to 11.49), p<0.001).ConclusionThe clinical prognosis factors we have described support published studies. Here, we also suggest that brain PET is of interest for prognosis assessment and in particular in the search for left insula hypometabolism. Moreover, SSRIs are a potential drug candidate to slow the progression of the disease.
Physiological and prognostic differences between types of exercise stress echocardiography for functional mitral regurgitation
Authors: Kagiyama Nobuyuki , Toki Misako , Yuri Takuya , Aritaka Shingo , Hayashida Akihiro , Sengupta Partho P , Yoshida Kiyoshi 
Published: April 2021

ObjectiveSecondary mitral regurgitation (MR) demonstrates dynamic change during exercise. This prospective observational study aimed to compare exercise stress echocardiography (ESE) where handgrip exercise (handgrip-ESE) or semisupine ergometer exercise was performed (ergometer-ESE) for patients with secondary MR.MethodsHandgrip-ESE and symptom-limited ergometer-ESE were performed for 53 patients (median age (IQR): 68 (58–78) years; 70% male) on the same day. Baseline global longitudinal strain (GLS) was 9.2% (6.0%–14.0%) and MR volume was 20 (14–26) mL. All-cause death and cardiac hospitalisation were tracked for median 439 (101–507) days.ResultsHandgrip-ESE induced slightly but significantly greater degrees of MR increase (median one grade increase; p<0.001) than ergometer-ESE, although the changes in other parameters, including GLS (+1.1% vs −0.6%, p<0.001), were significantly smaller. Correlations between the two examinations with respect to the changes in the echocardiographic parameters were weak. Kaplan-Meier analyses revealed poor improvement in GLS during ergometer-ESE, but not the change in MR, was associated with adverse events (p=0.0065). No echocardiographic change observed during handgrip-ESE was prognostic. After adjusting for a clinical risk score, GLS changes during ergometer-ESE remained significant in predicting the adverse events (HR 0.39, p=0.03) A subgroup analysis in patients with moderate or greater MR at baseline (n=27) showed the same results as in the entire cohort.ConclusionsThe physiological and prognostic implications of handgrip-ESE and ergometer-ESE findings significantly differ in patients with left ventricular dysfunction and secondary MR. The type of exercise to be performed in ESE should be carefully selected.