bluuebunny/crossref_metadata_2025 huggingface dataset:
Ediacaran–Cambrianbioturbation did not extensively oxygenate sediments in shallow marine ecosystems
Authors: Cribb Alison T. , van de Velde Sebastiaan J. , Berelson William M. , Bottjer David J. , Corsetti Frank A.
Published: February 2023

The radiation of bioturbation during the Ediacaran–Cambrian transition has long been hypothesized to have oxygenated sediments, triggering an expansion of the habitable benthic zone and promoting increased infaunal tiering in early Paleozoic benthic communities. However, the effects of bioturbation on sediment oxygen are underexplored with respect to the importance of biomixing and bioirrigation, two bioturbation processes which can have opposite effects on sediment redox chemistry. We categorized trace fossils from the Ediacaran and Terreneuvian as biomixing or bioirrigation fossils and integrated sedimentological proxies for bioturbation intensity with biogeochemical modeling to simulate oxygen penetration depths through the Ediacaran–Cambrian transition. Ultimately, we find that despite dramatic increases in ichnodiversity in the Terreneuvian, biomixing remains the dominant bioturbation behavior, and in contrast to traditional assumptions, Ediacaran–Cambrian bioturbation was unlikely to have resulted in extensive oxygenation of shallow marine sediments globally.
Sintering behavior of 8YSZ‐Ni cermet: Comparison between conventional, FST/SPS, and flash sintering
Authors: Mundra Raghav , Mishra Tarini Prasad , Bram Martin , Guillon Olivier , Yadav Devinder
Published: February 2023

Cermets are ceramic metal composites. The metallic phase in the cermet typically undergoes oxidation during sintering in air. Electric field‐assisted sintering processes such as field‐assisted sintering technology/spark plasma sintering (FAST/SPS) and flash involves very high heating rates, short processing time and low processing temperature. The main aim of this work was to see if field‐assisted sintering techniques can prevent the oxidation of the metallic phase in the cermet. Sintering behavior of 8YSZ‐5 wt.% Ni cermet was studied by three different techniques namely; conventional sintering, FAST/SPS and flash sintering. Phases and microstructure were analyzed through X‐ray diffraction and scanning electron microscopy, respectively. Temperature and time required for sintering the samples via FAST/SPS and flash sintering was significantly lower than that during conventional sintering. In addition, we found limited grain growth during FAST/SPS and flash sintering. During conventional sintering in reducing atmosphere (Ar and vacuum), Ni particles retained their elemental state, however the extent of densification was poor in the cermet. FAST/SPS in argon and vacuum resulted in almost complete densification (relative density > 97%) and Ni particles were retained in their elemental state in the cermet. During flash sintering in air, the samples sintered to a high densification (relative density ∼98%), however, Ni particles were completely oxidized.
Simultaneous hardening and toughening of a high‐entropy (NbTaZrW)C ceramic carbide using SiC particle
Authors: Peng Fei , Wei Zhen , Song Qianqian , He Liu , Dai Fengfeng , Zhang Weidong , Wu Zhenggang
Published: February 2023

Previously, we have found that (NbTaZrW)C exhibits a good combination of nanohardness and toughness. In this report, we explore the possibility to further increase the overall properties of this high‐entropy carbide ceramic (HECC) through introducing SiC particle (SiCP). To this end, a series of (NbTaZrW)C–xSiC ceramic composites (x = 0/5/15/30/50 vol.%) were fabricated using spark plasma sintering (SPS), their microstructure and mechanical properties were characterized. Our results reveal a grain refinement effects of SiCP, an agglomeration of SiCP with (1 0 0) plane preferentially perpendicular to the SPS‐pressing direction and the formation of a transition region with various stoichiometric ratio of (NbTaZrW)xC1−x in the (NbTaZrW)C–SiCP vicinity. The elastic modulus, microhardness, and flexural strength of the HECCs show tight positive relations with the SiCP content and the beneficial effect of SiCP to the fracture toughness of (NbTaZrW)C becomes evident once the content of SiCP reaches 30 vol.%. Altogether, (NbTaZrW)C–50%SiC, which has a microhardness of 22 GPa, a flexural strength of 455 MPa, and an indentation fracture toughness of 6.54 MPa m1/2, presents the optimal combination of mechanical properties among the investigated composites. Mechanistically, the strengthening effect of SiCP introduction arises from the intrinsic high hardness of SiCP and the SiCP‐induced grain refinement and the toughening effect is mainly associated with crack bridging mechanism.
Psychometric properties of patient‐reported outcome measures assessing self‐efficacy in patients with inflammatory bowel disease: A systematic review
Authors: Fang Yan‐Qiu , Chong Ting‐Ting , Wu Di , Qian Li
Published: February 2023

Aims

The aim of this study is to conduct a comprehensive evaluation of the patient‐reported outcome measure assessing self‐efficacy in patients with inflammatory bowel disease, and recommend the most robust measurement.

Design

A systematic review of psychometric properties.

Data Sources

We performed systematic electronic searches in the following databases from inception to 26 May 2022: PubMed, Embase, CINAHL, Web of Science, Cochrane Library, and PsycINFO via OVID.

Review Method

This review evaluated the tools' quality in accordance with the Selection of Consensus‐Based Health Measurement Instruments 2018 system Evaluation guidelines.

Results

Three patient‐reported outcome measures were identified in the five included studies. The “IBD‐yourself” questionnaire revealed very low evidence for a sufficient hypothesis test for construct validity, moderate evidence for insufficient internal consistency, and very low evidence for uncertain measurement error. Evidence from Inflammatory Bowel Disease Self‐Efficacy Scale validated internal consistency, structural validity, criterion validity, and hypothesis test for construct validity. However, evidence of moderate quality corroborated this reliability. The Adolescents and Young Adults Inflammatory Bowel Disease Self‐Efficacy Scale demonstrated very low evidence for sufficient internal consistency, moderate evidence for a sufficient hypothesis test for construct and content validity, and very low evidence for uncertain reliability.

Conclusions

Compared with the other two measures, the Inflammatory Bowel Disease Self‐Efficacy Scale has higher quality evidence of higher overall ratings for some of its psychometric properties, but there were some methodological problems that must be further studied to determine their quality.

Impact

It is uncertain whether a scale to assess self‐efficacy in patients with inflammatory bowel disease has good measurement performance in clinical applications. This study first presents the methodological quality and psychometric properties of the self‐efficacy scale used to assess patients with inflammatory bowel disease, which is based on the Consensus‐Based Health Measurement Instruments standard. This study can help researchers and physicians decide which scale is the most suitable and reliable for patients with inflammatory bowel disease.

No Patient or Public Contribution

Because this was a systematic review based on synthesizing information from previous studies, no human participants were included.
Adenosine monophosphate deaminase in the endoplasmic reticulum–mitochondria interface promotes mitochondrial Ca2+ overload in type 2 diabetes rat hearts
Authors: Osanami Arata , Sato Tatsuya , Toda Yuki , Shimizu Masaki , Kuno Atsushi , Kouzu Hidemichi , Yano Toshiyuki , Ohwada Wataru , Ogawa Toshifumi , Miura Tetsuji , Tanno Masaya
Published: February 2023

Aims/Introduction

We previously showed that upregulation of myocardial adenosine monophosphate deaminase (AMPD) is associated with pressure overload‐induced diastolic dysfunction in type 2 diabetes hearts. Here, we examined involvement of AMPD localized in the endoplasmic reticulum–mitochondria interface in mitochondrial Ca2+ overload and its pathological significance.

Materials and Methods

We used type 2 diabetes Otsuka Long–Evans Tokushima Fatty rats (OLETF) and non‐diabetes Long–Evans Tokushima Otsuka Fatty rats (LETO) as well as AMPD3‐overexpressing H9c2 cells and human embryonic kidney 293 cells.

Results

OLETF, but not LETO, showed diastolic dysfunction under the condition of phenylephrine‐induced pressure overload. The levels of 90‐kDa AMPD3 in outer mitochondrial membranes/endoplasmic reticulum and mitochondria‐associated endoplasmic reticulum membrane (MAM) fractions were significantly higher in OLETF than in LETO. The area of the MAM quantified by electron microscopic analysis was 57% larger, mitochondrial Ca2+ level under the condition of pressure overload was 47% higher and Ca2+ retention capacity in MAM‐containing crude mitochondria isolated before the pressure overloading was 21% lower in OLETF than in LETO (all P‐values <0.05). Transfection of FLAG‐AMPD3 in cells resulted in significant enlargement of the MAM area, and impairment in pyruvate/malate‐driven adenosine triphosphate‐stimulated and uncoupler‐stimulated mitochondrial respiration compared with those in control cells.

Conclusions

The findings suggest that 90‐kDa AMPD3 localized in the endoplasmic reticulum–mitochondria interface promotes formation of the MAM, inducing mitochondrial Ca2+ overload and dysfunction in type 2 diabetes hearts.
Automated tea quality identification based on deep convolutional neural networks and transfer learning
Authors: Zhang Cheng , Wang Jin , Lu Guodong , Fei Shaomei , Zheng Tao , Huang Bincheng
Published: February 2023

Different quality grades of tea tend to have a high degree of similarity in appearance. Traditional image‐based identification methods have limited effects, while complex deep learning architectures require much data and long‐term training. In this paper, two tea quality identification methods based on deep convolutional neural networks and transfer learning are proposed. Different types and quality of tea images are collected by a self‐designed computer vision system to form a data set, which is small‐scale and of high inter‐ and intraclass similarity. The first method uses three simplified convolutional neural network (CNN) models with different image input sizes to identify the quality of tea. The second method performs transfer learning to identify the tea quality by fine‐tuning the mature AlexNet and ResNet50 architecture. Classification performance and model complexity are measured and compared. The related application software is also developed. The results show that the performance of the CNN models and the transfer learning models are close, and both can achieve high identification accuracy. However, the complexity of the CNN models is two to three orders of magnitude lower than that of the transfer learning models. The study shows that deep CNNs and transfer learning have great potential to be rapid and effective methods for automated tea quality identification tasks with high inter‐ and intrasimilarity.
Tele‐visits for GERD: “Ecofriendly, efficient and effective”
Authors: Roy Winnie , Hans Bandhul , Jannat Rida Ul , Reddy Yala Kirthi , Hadi Yousaf , Gayam Swapna
Published: February 2023

Background and Aim

Sars‐CoV‐19 pandemic necessitated a transition to telemedicine for many healthcare encounters. The environmental impact of this transition in gastroenterology (GI) combined with user experience has not been studied.

Methods

We conducted a retrospective cohort study of patients who underwent telemedicine visits (telephone and video) at a GI clinic at West Virginia University.

Distance of patients' residence from clinic × 2 was calculated, and Environmental Protection Agency calculators utilized to calculate greenhouse gas (GHG) emissions that were avoided from tele‐visits.

Patients were reached by telephone and were asked questions to fill in a validated Telehealth Usability Questionnaire with Likert scales (1–7). Variables were also collected via chart review.

Results

A total of 81 video and 89 telephone visits were conducted for gastroesophageal reflux disease (GERD) between March 2020 and March 2021. A total of 111 patients were enrolled, with a response rate of 65.29%. Mean age was lower in the video visit cohort compared with the telephone visit cohort (43.45 ± 14.32 years vs 52.34 ± 17.46 years). Most patients had medications prescribed during the visit (79.3%), and a majority had laboratory testing orders placed (57.7%).

We calculated a total distance of 8732 miles that the patients would have traveled if they were to present for in‐person visits (including return trips). A total of 393.3 gallons of gasoline would have been required to transport these patients to and from the healthcare facility to their residence. A total of 3.5 metric tons of GHG's were saved by avoiding 393.3 gallons of gasoline for travel. In relatable terms, this is equivalent to burning more than 3500 pounds of coal. This averages to 31.5‐kg GHG emissions and 3.54 gallons of gasoline saved per patient.

Conclusion

Telemedicine for GERD resulted in significant environmental savings and was rated highly for access, satisfaction, and usability by patients. Telemedicine for GERD can be an excellent alternative to in‐person visits.
Association between specific unmet functional needs and desire to institutionalize among caregivers of older veterans
Authors: Brenner Rachel J. , Hansen Jared , Brintz Ben J. , Bouldin Erin D. , Pugh Mary Jo , Rupper Randall , Munoz Richard , Garcia‐Davis Sandra , Dang Stuti
Published: February 2023

Objectives

To evaluate the associations between specific functional needs of older Veterans and the desire to institutionalize (DTI) among their caregivers.

Methods

Cross‐sectional multivariable logistic regression analysis of 3579 Hero Care survey responses from caregivers of Veterans at five US sites from July to December 2021. Unmet needs were areas in which the caregiver reported the Veteran needed a little more or a lot more help. Caregiver DTI was defined as the caregiver reporting that they had discussed, considered, or taken steps toward a nursing home or assisted living placement for the Veteran or that they felt the Veteran would be better off in such a setting or they were likely to move the Veteran to another living arrangement.

Results

Caregivers were largely white, retired, females with an average age of 71 and with some college education who spent an average of 8–9 h per day 6 days a week caring for a Veteran spouse. There was evidence of associations between the following needs and a DTI: managing incontinence, using the telephone, transportation, and arranging services in the home such as visiting nurses, home care aides, or meals on wheels. Unmet functional needs in other selected domains were not associated with the DTI.

Conclusion

Among caregivers of older Veterans, a need for more assistance managing incontinence, telephone use, transportation, and arranging in‐home services were associated with the DTI. These may represent functional markers of important clinical determinants for institutionalization as well as potential targets for intervention to reduce caregiver DTI, such as programs that provide more caregiver or Veteran support in the home to meet these needs and reduce caregiver burden.
Risk factors for impaired respiratory function post COVID‐19: A prospective cohort study of nonhospitalized and hospitalized patients
Authors: Björsell Tove , Sundh Josefin , Lange Anna , Ahlm Clas , Forsell Mattias N.E. , Tevell Staffan , Blomberg Anders , Edin Alicia , Normark Johan , Cajander Sara
Published: February 2023

Background

Severe COVID‐19 increases the risk for long‐term respiratory impairment, but data after mild COVID‐19 are scarce. Our aims were to determine risk factors for reduced respiratory function 3–6 months after COVID‐19 infection and to investigate if reduced respiratory function would relate to impairment of exercise performance and breathlessness.

Methods

Patients with COVID‐19 were enrolled at the University Hospitals of Umeå and Örebro, and Karlstad Central Hospital, Sweden. Disease severity was defined as mild (nonhospitalized), moderate (hospitalized with or without oxygen treatment), and severe (intensive care). Spirometry, including diffusion capacity (DLCO), was performed 3–6 months after hospital discharge or study enrollment (for nonhospitalized patients). Breathlessness (defined as ≥1 according to the modified Medical Research Council scale) and functional exercise capacity (1‐min sit‐to‐stand test; 1‐MSTST) were assessed.

Results

Between April 2020 and May 2021, 337 patients were enrolled in the study. Forced vital capacity and DLCO were significantly lower in patients with severe COVID‐19. Among hospitalized patients, 20% had reduced DLCO, versus 4% in nonhospitalized. Breathlessness was found in 40.6% of the participants and was associated with impaired DLCO. A pathological desaturation or heart rate response was observed in 17% of participants during the 1‐MSTST. However, this response was not associated with reduced DLCO.

Conclusion

Reduced DLCO was the major respiratory impairment 3–6 months following COVID‐19, with hospitalization as the most important risk factor. The lack of association between impaired DLCO and pathological physiological responses to exertion suggests that these physiological responses are not primarily related to decreased lung function.
Breastfeeding in infancy and mortality in middle and late adulthood: A prospective cohort study and meta‐analysis
Authors: Wang Xiaoyan , Yan Mengsha , Zhang Yanyu , Wang Wenjie , Zhang Weiwei , Luo Junkai , Gan Da , Yang Haomin , Zhu Shankuan , He Wei
Published: February 2023

Background

Breastfeeding in infancy is associated with a lower risk of mortality among children, but the impact on mortality in middle and late adulthood remains unknown.

Objectives

To assess the association between breastfeeding in infancy and mortality in middle and late adulthood.

Methods

We included 383,627 participants aged 40–73 from the UK Biobank (2006–2010) and followed up until 2021. Hazard ratios (HRs) and 95% confidence intervals (CIs) for all‐cause and cause‐specific mortality according to breastfeeding in infancy were estimated with Cox proportional hazards regression models. We further did a meta‐analysis, including results from our present study and three other cohort studies (PROSPERO; number CRD42022348925).

Results

During a total of 4732,751 person‐years of follow‐up, 25,581 deaths were identified. Breastfeeding in infancy was associated with lower risks of mortality in middle and late adulthood, with adjusted HRs (95% CIs) of 0.95 (0.93–0.98) for all‐cause mortality; 0.91 (0.87–0.96) for cardiovascular mortality and 0.94 (0.874–0.999) for respiratory mortality. Specifically, the association with mortality seemed to attenuate with age – stronger in middle‐aged adults than in older adults. A similar association between breastfeeding in infancy and all‐cause mortality was found in the meta‐analysis.

Conclusion

Breastfeeding in infancy is associated with a lower risk of mortality – even decades later – in middle and late adulthood.
Reproducing crises: Understanding the role of law in the COVID‐19 global pandemic
Authors: Atiles Jose , Whyte David
Published: February 2023

Governmental responses to the COVID‐19 global pandemic have generated numerous constitutionals, policy, legal, and political‐economic debates. Scholarly engagements with the sociolegal and policy consequences of the COVID‐19 pandemic have been dominated by discussion on the role of emergency powers, the suspension of individual civil liberties, the suspension of economic rules in order to guarantee economic survival, and social regulation of public spaces and of workplaces. This paper aims to explore how a critical sociolegal scholarship can contribute to a more sophisticated understanding of the role of law in creating the unequal conditions that propitiated the COVID‐19 pandemic and that might enable further crises. This introduction offers a roadmap for theorizing the limits of law, the operationalization of emergency powers and the different policies implemented by global south and north countries in response to the pandemic. This introduction is structured as follow: (1) provides a general overview of the law and society tradition and its engagement with the COVID‐19 pandemic; (2) engages with three key consequences of the pandemic, labor, and the lockdown; colonial implications; and the limits of law; (3) introduces the papers in this special issue; (4) sketches a proposal for the critical sociolegal scholarship of law and crises.
Genomic responses to parallel temperature gradients in the eelgrass Zostera marina in adjacent bays
Authors: Schiebelhut Lauren M. , Grosberg Richard K. , Stachowicz John J. , Bay Rachael A.
Published: February 2023

The extent of parallel genomic responses to similar selective pressures depends on a complex array of environmental, demographic, and evolutionary forces. Laboratory experiments with replicated selective pressures yield mixed outcomes under controlled conditions and our understanding of genomic parallelism in the wild is limited to a few well‐established systems. Here, we examine genomic signals of selection in the eelgrass Zostera marina across temperature gradients in adjacent embayments. Although we find many genomic regions with signals of selection within each bay there is very little overlap in signals of selection at the SNP level, despite most polymorphisms being shared across bays. We do find overlap at the gene level, potentially suggesting multiple mutational pathways to the same phenotype. Using polygenic models we find that some sets of candidate SNPs are able to predict temperature across both bays, suggesting that small but parallel shifts in allele frequencies may be missed by independent genome scans. Together, these results highlight the continuous rather than binary nature of parallel evolution in polygenic traits and the complexity of evolutionary predictability.
How medical learners and educators decide what counts as mistreatment: A qualitative study
Authors: Vanstone Meredith , Cavanagh Alice , Molinaro Monica , Connelly Catherine E. , Bell Amanda , Mountjoy Margo , Whyte Robert , Grierson Lawrence
Published: February 2023

Introduction

The mistreatment or abuse (maltreatment) of medical learners by their peers and supervisors has been documented globally for decades, and there is significant research about the prevalence, sequelae and strategies for intervention. However, there is evidence that learners experience maltreatment as being less clear cut than do researchers, educators and administrators. This definitional ambiguity creates problems for understanding and addressing this issue. The objective of this study was to understand how medical learners and educators make sense of less‐than‐ideal interactions in the clinical learning environment, and to describe which factors influenced their perception that the encounter constituted maltreatment.

Methods

Using constructivist grounded theory, we interviewed 16 medical students, 15 residents or fellows, and 18 educators associated with a single medical school (n = 49). Data collection began with the most junior learners, iterating with analysis as we progressed through the project. Constant comparative analysis was used to gather and compare stories of ‘definitely’, ‘maybe’ and ‘definitely not’ maltreatment across a variety of axes including experience level, clinical setting and type of interaction.

Results

Our data show that learners and educators have difficulty classifying their experiences of negative interpersonal interaction, except in the most severe and concrete cases. While there was tremendous variation in the way they categorised similar experiences, there was consistency in the elements drawn upon to make sense of those experiences. Participants interpreted negative interpersonal interactions on an individual basis by considering factors related to the interaction, initiator and recipient.

Conclusions

Only the most negative behaviour is consistently understood as maltreatment; a complex process of individual sense‐making is required to determine the acceptability of each interaction. The differences between how individuals judge these interactions highlight an opportunity for administrative, research and faculty development intervention.
Congenital erosive and vesicular dermatosis healing with reticulated and supple scarring: Two cases secondary to fungal infection
Authors: Shope Chelsea , Cotton Colleen H. , Wine Lee Lara
Published: February 2023

Congenital erosive and vesicular dermatosis (CEVD) is a rare skin condition that most commonly presents as erosive and vesicular lesions on the trunk and extremities in premature infants and heals with characteristic reticulated and supple scarring (RSS). The exact pathogenesis of CEVD is unknown and is typically a diagnosis of exclusion. We present the cases of two extremely premature neonates with Candida septicemia who were found to have diffuse, erythematous skin eruptions shortly after birth that ultimately healed with RSS. Through these cases, we highlight the importance of including fungal infection in the work‐up of CEVD healing with RSS.
Validation and application of new NGS‐based HLA genotyping to clinical diagnostic practice
Authors: Kim Ji Yeon , Lee Seung Yeob , Kim Ga‐Gyoung , Song Hae‐In , Jang Mi Mi , Lee Chang Seon , Hong Ju Yeon , Shin Myung‐Geun , Choi Hyun‐Jung
Published: February 2023

Next‐generation sequencing (NGS) has revolutionized clinical genotyping, providing high‐resolution HLA genotyping with a low ambiguity rate. This study aimed to develop new NGS‐based HLA genotyping (HLAaccuTest, NGeneBio, Seoul, KOREA) on the Illumina MiSeq platform and validate the clinical performance. The analytical performance of HLAaccuTest was validated for 11 loci comprising HLA‐A, ‐B, ‐C, ‐DRB1/3/4/5, ‐DQA1, ‐DQB1, ‐DPA1, and ‐DPB1 using 157 reference samples. Among the 345 clinical samples, 180 were tested for performance evaluation and protocol optimization, and 165 were used in clinical trials in the validation phase for five loci, including HLA‐A, ‐B, ‐C, ‐DRB1, and ‐DQB1. In addition, the improvement in the resolution of ambiguous alleles was also evaluated and compared with other NGS‐based HLA genotyping for 18 reference samples, including five overlapping samples in analytical performance validation. All reference materials produced 100% concordant results for 11 HLA loci, 96.9% (2092 of 2160 HLA alleles) of the clinical samples were matched with the SBT results in the pre‐validation phase. After the optimization phase, the clinical trials in the validation phase showed 99.7% (1645/1650 alleles) concordance with the complete resolution for 34 ambiguity results. The retesting of five discordant cases resolved all issues and yielded 100% concordant results with the SBT method. Additionally, for ambiguity using 18 reference materials with ambiguous alleles, about 30% of ambiguous alleles were more resolved than Trusight HLA v2. HLAaccuTest was successfully validated using a large volume of clinical samples and is fully applicable to the clinical laboratory.
Assessment of glomerular filtration and tubular secretion in baboons with life‐supporting pig kidney grafts
Authors: Hansen‐Estruch Christophe , Bikhet Mohamed H. , Shaik Imam H. , Vasudevan Vignesh , Zhao Wenchen , Javed Mariyam , Collins Dalis E. , Ayares David , Judd Eric , Cooper David K. C. , Venkataramanan Raman
Published: February 2023

With pig kidney xenotransplantation nearing clinical reality, it is imperative to measure pig kidney function in the graft recipients. Our aims were (i) to compare inulin clearance after a short intravenous (IV) bolus with steady‐state inulin IV infusion, (ii) to use this method to measure the glomerular filtration rate (GFR), and (iii) to determine the tubular secretory function using cefoxitin in a pig‐to‐baboon renal transplant model. A short IV infusion of inulin and cefoxitin were followed by a maintenance IV infusion of inulin over 5 h in seven healthy baboons, three healthy pigs, and five baboons after bilateral native nephrectomy and intra‐abdominal pig renal transplantation. Blood and urine samples were collected. Serum and urinary inulin and serum cefoxitin concentrations measured by validated assays were used to calculate GFR and renal secretion. GFR calculated were similar by both methods. The body weight normalized total body clearance of inulin was similar in pigs and baboons despite differences in absolute clearances. Pig kidney transplanted into baboons provided similar clearance in baboons when normalized to baboon body weight and sustained filtration and secretory functions. The study documented that pig kidneys support the physiologic needs of baboons and are likely to support human recipients as well.
Exercise and ageing impact the kynurenine/tryptophan pathway and acylcarnitine metabolite pools in skeletal muscle of older adults
Authors: Hinkley J. Matthew , Yu Gong Xin , Standley Robert A. , Distefano Giovanna , Tolstikov Vladimir , Narain Niven R. , Greenwood Bennett P. , Karmacharya Shraddha , Kiebish Michael A. , Carnero Elvis Alvarez , Yi Fanchao , Vega Rick B. , Goodpaster Bret H. , Gardell Stephen J. , Coen Paul M.
Published: February 2023

Exercise‐induced perturbation of skeletal muscle metabolites is a probable mediator of long‐term health benefits in older adults. Although specific metabolites have been identified to be impacted by age, physical activity and exercise, the depth of coverage of the muscle metabolome is still limited. Here, we investigated resting and exercise‐induced metabolite distribution in muscle from well‐phenotyped older adults who were active or sedentary, and a group of active young adults. Percutaneous biopsies of the vastus lateralis were obtained before, immediately after and 3 h following a bout of endurance cycling. Metabolite profile in muscle biopsies was determined by tandem mass spectrometry. Mitochondrial energetics in permeabilized fibre bundles was assessed by high resolution respirometry and fibre type proportion was assessed by immunohistology. We found that metabolites of the kynurenine/tryptophan pathway were impacted by age and activity. Specifically, kynurenine was elevated in muscle from older adults, whereas downstream metabolites of kynurenine (kynurenic acid and NAD+) were elevated in muscle from active adults and associated with cardiorespiratory fitness and muscle oxidative capacity. Acylcarnitines, a potential marker of impaired metabolic health, were elevated in muscle from physically active participants. Surprisingly, despite baseline group difference, acute exercise‐induced alterations in whole‐body substrate utilization, as well as muscle acylcarnitines and ketone bodies, were remarkably similar between groups. Our data identified novel muscle metabolite signatures that associate with the healthy ageing phenotype provoked by physical activity and reveal that the metabolic responsiveness of muscle to acute endurance exercise is retained with age regardless of activity levels.

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Key points

Kynurenine/tryptophan pathway metabolites were impacted by age and physical activity in human muscle, with kynurenine elevated in older muscle, whereas downstream products kynurenic acid and NAD+ were elevated in exercise‐trained muscle regardless of age.

Acylcarnitines, a marker of impaired metabolic health when heightened in circulation, were elevated in exercise‐trained muscle of young and older adults, suggesting that muscle act as a metabolic sink to reduce the circulating acylcarnitines observed with unhealthy ageing.

Despite the phenotypic differences, the exercise‐induced response of various muscle metabolite pools, including acylcarnitine and ketone bodies, was similar amongst the groups, suggesting that older adults can achieve the metabolic benefits of exercise seen in young counterparts.
Partition-Aware Stability Control for Humanoid Robot Push Recovery With Whole-Body Capturability
Authors: Song Hyunjong , Peng William Z. , Kim Joo H.
Published: February 2023

For successful push recovery in response to perturbations, a humanoid robot must select an appropriate stabilizing action. Existing approaches are limited because they are often derived from reduced-order models that ignore system-specific aspects such as swing leg dynamics or kinematic and actuation limits. In this study, the formulation of capturability for whole-body humanoid robots is introduced as a partition-based approach in the augmented center-of-mass (COM)-state space. The 1-step capturable boundary is computed from an optimization-based method that incorporates whole-body system properties with full-order nonlinear system dynamics in the sagittal plane including contact interactions with the ground and conditions for achieving a complete stop after stepping. The 1-step capturable boundary, along with the balanced state boundaries, are used to quantify the relative contributions of different strategies and contacts in maintaining or recovering balance in push recovery. The computed boundaries are also incorporated as explicit criteria into a partition-aware push recovery controller that monitors the robot’s COM state to selectively exploit the ankle, hip, or captured stepping strategies. The push recovery simulation experiments demonstrated the validity of the stability boundaries in fully exploiting a humanoid robot’s balancing capability through appropriate balancing actions in response to perturbations. Overall, the system-specific capturability with the whole-body system properties and dynamics outperformed that derived from a typical reduced-order model.
Direct Encoding of Tunable Stiffness Into an Origami-Inspired Jumping Robot Leg
Authors: Chen Fuchen , Aukes Daniel M.
Published: February 2023

The stiffness of robot legs greatly affects legged locomotion performance; tuning that stiffness, however, can be a costly and complex task. In this paper, we directly tune the stiffness of jumping robot legs using an origami-inspired laminate design and fabrication method. In addition to the stiffness coefficient described by Hooke’s law, the nonlinearity of the force-displacement curve can also be tuned by optimizing the geometry of the mechanism. Our method reduces the number of parts needed to realize legs with different stiffness while simplifying manual redesign effort, lowering the cost of legged robots while speeding up the design and optimization process. We have fabricated and tested the leg across six different stiffness profiles that vary both the nonlinearity and coefficient. Through a vertical jumping experiment actuated by a DC motor, we also show that proper tuning of the leg stiffness can result in an 18% improvement in lift-off speed and an increase of 19% in peak power output.
Force Analysis of Statically Balanced Serially Connected Manipulators Using Springs Based on Torque Compatibilities Associated With Accumulative Joint Angles
Authors: Jhuang Chi-Shiun , Juang Chia-Wei , Chen Dar-Zen
Published: February 2023

Force analysis with regard to serial connected manipulators is discussed thoroughly in the past. However, force analysis of statically balanced manipulator using springs has not been widely addressed because spring forces and motions do not share an immediate association. In this article, spring forces are represented as accumulative joint angles of links crossed by springs and attached angles/lengths of springs. Torque equilibrium equations regarding the preconnected joint of a typical link as contributed by gravity force and spring force can be inwardly formed link by link from the end link. Compatibility with the same accumulative joint angle can be formulated under static balance conditions. Hence, spring attachment parameters such as spring stiffness and attachment lengths are constrained by given link properties and spring attachment angles. Thus, spring forces can be determined by a chosen set of stiffness and attached lengths of springs, and the joint reaction force can then be determined. Example figures of 3-degrees-of-freedom (DOFs) manipulators show that joint reaction forces are reduced by 22.6%, 40.1%, and 75.7% at joints 1, 2, and 3, respectively, than those without springs. It is found that besides balancing gravity, the statically balanced manipulator is with lower joint reaction forces. Hence, the manipulator can be more lightweight by using compact joints and links with the same material. Furthermore, the static and dynamic performance of the manipulator can be improved by the effect of reduced joint reaction forces as well.
Theoretical Modeling of Vibrations of Mechanically Assembled 3D Serpentine Structures
Authors: Zhao Jianzhong , Cao Huijie , Shuai Yumeng
Published: February 2023

Vibration of micro-electromechanical systems (MEMS) is of growing interest for applications in vibration measurements, vibration energy harvesters, and vibration sensors. Among the structures and devices reported, a class of 3D structures formed by mechanically guided assembly is showing promising potentials, owing to the ability of controlled vibration behaviors (e.g., modes and natural frequencies) by reversibly changing the compressive strain. In addition, serpentine structures are good candidates for MEMS due to their ultra-low natural frequencies. Hence, we present a study on the vibration of the mechanically assembled 3D serpentine structures. A theoretical model is established to capture the vibration mechanism, and therefore, a simple analytical expression for the natural frequency is derived. On this basis, the influence of material/geometry parameters on the natural frequency is systematically discussed. The developed analytical model would provide a better understanding of vibration mechanism in mechanically assembled 3D structures
Pulling a Spool
Authors: Mungan Carl E.
Published: February 2023

A simple model for the kinetic frictional force on an object sliding across a surface is adopted in introductory physics. Its magnitude is given by a constant coefficient of kinetic friction multiplied by the normal force exerted on the object by the surface, and the force points opposite the direction that the object slides relative to the surface. In contrast, the standard model for the static frictional force is more complicated. There is no formula for its magnitude, but instead it can vary from zero up to some maximum value, as required to keep the point of contact of the object at rest relative to the surface it is on. Furthermore, it points in the direction opposite the way in which the object would slip at its point of contact if there were zero friction, but it is not always obvious which way that is. In an attempt to bypass these complications, students can make erroneous assumptions about the magnitude and direction of the static frictional force. To counter them, it is helpful to present some example that shows students that those assumptions need not hold. Such a system is a pulled spool that rolls without slipping on a horizontal table. Since the point of contact between the spool and the table does not slip, any frictional force between them must be static.
Gauss Theorem and Pointlike Charges: When Infinitesimals Make the Difference
Authors: Agnesi Antonio
Published: February 2023

A classic application of the Gauss theorem is examined, showing how the choice of the Gaussian surface and the pointlike nature of the charge can determine results somehow unexpected for the student. Particular care must be paid not only to points where the field becomes infinite, but also to infinitesimal displacements of the charge and their direction. Pedagogical implications are outlined.
Coulomb’s Law: Augmented Reality Simulation
Authors: Vidak Andrej , Šapić Iva Movre , Dananić Vladimir , Batista Jadranko
Published: February 2023

Coulomb’s law is a typical representative of the inverse-square laws that appear in various learning contexts in physics. In the usual classroom setting, most students do not have the opportunity to experimentally discover the interdependence of variables described by this law. Recently, digital technologies have become more prevalent at all levels of education. Teachers and researchers are successfully using computer-based simulations to improve physics education. Augmented reality is one of the emerging digital technologies that have the potential to improve students’ understanding of a wide range of educational topics. Nevertheless, it is advisable that students and teachers are familiar with the most efficient use of selected digital tools before using augmented reality-enriched physics lectures. In this paper, we present our augmented reality simulation called CoulombsLawAR, which could be useful for teaching Coulomb’s law.
Self-guided field trips as an alternative to final exams
Authors: Lincoln James
Published: February 2023

Recently, I was inspired to try a new type of assignment: the self-guided field trip report. Last semester, as I was teaching a new course, Astrophysics, I found myself uninterested in administering a traditional final exam. Feeling that astrophysics was out in the world, I decided that students could go out and find it if only given the opportunity. The assignment went well and brought new learning and joy to both teacher and students. In this article, I describe the lesson and share some results.
Familiar and unfamiliar speaker recognition assessment and system emulation for cochlear implant users
Authors: Mamun Nursadul , Ghosh Ria , Hansen John H. L.
Published: February 2023

In the area of speech processing, human speaker identification under naturalistic environments is a challenging task, especially for hearing-impaired individuals with cochlear implants (CIs) or hearing aids (HAs). Motivated by the fact that electrodograms reflect direct CI stimulation of input audio, this study proposes a speaker identification (ID) investigation using two-dimensional electrodograms constructed from the responses of a CI auditory system to emulate CI speaker ID capabilities. Features are extracted from electrodograms through an identity vector (i-vector) framework to train and generate identity models for each speaker using a Gaussian mixture model-universal background model followed by probabilistic linear discriminant analysis. To validate the proposed system, perceptual speaker ID for 20 normal hearing (NH) and seven CI listeners was evaluated with a total of 41 different speakers and compared with the scores from the proposed system. A one-way analysis of variance showed that the proposed system can reliably predict the speaker ID capability of CI (F[1,10] = 0.18, p = 0.68) and NH (F[1,20] = 0, p = 0.98) listeners in naturalistic environments. The impact of speaker familiarity is also addressed, and the results show a reduced performance for speaker recognition by CI subjects using their CI processor, highlighting limitations of current speech processing strategies used in CIs/HAs.
Propagation of fundamental Lamb modes along the non-principal axes of strain-stiffened soft compressible plates: A numerical investigation
Authors: Patra Asesh Kumar , Sharma Atul Kumar , Joglekar D. M. , Joglekar M. M.
Published: February 2023

This paper numerically investigates the propagation of elastic plate waves along the non-principal directions in a prestretched compressible material described by the Gent model of hyperelasticity. We formulate the elastic tensor and the underlying wave equations in the Lagrangian space by employing the theory of nonlinear elasticity together with the linearized incremental equations. An extension of the Semi-Analytical Finite Element (SAFE) method is discussed for computing the dispersion characteristics of the two fundamental guided wave modes. The predictive capabilities of the numerical framework are established using the previously published data for a weakly nonlinear as well as hyperelastic material models. Using the numerical framework, we then bring out the effects of applied prestretch, orientation of the propagation direction, and material parameters on the dispersion characteristics of the fundamental Lamb modes. A limiting case of the neo-Hookean material model is first considered for elucidating such implicit dependencies, which are further highlighted by considering the strain-stiffening effect captured through the Gent material model. Our results indicate the existence of a threshold prestretch for which the Gent-type material can encounter a snap-through instability; leading to the change in the dispersion characteristics of the fundamental symmetric Lamb mode.
Population Pharmacokinetic Analysis of Rifampicin in Plasma, Cerebrospinal Fluid, and Brain Extracellular Fluid in South African Children with Tuberculous Meningitis
Authors: Abdelgawad Noha , Tshavhungwe Mvuwo (Phophi) , Rohlwink Ursula , McIlleron Helen , Abdelwahab Mahmoud T. , Wiesner Lubbe , Castel Sandra , Steele Chanel , Enslin Johannes (Nico) , Thango Nqobile Sindiswa , Denti Paolo , Figaji Anthony
Published: February 2023

Limited knowledge is available on the pharmacokinetics of rifampicin in children with tuberculous meningitis (TBM) and its penetration into brain tissue, which is the site of infection. In this analysis, we characterize the distribution of rifampicin in cerebrospinal fluid (CSF), lumbar (LCSF) and ventricular (VCSF), and brain extracellular fluid (ECF).
Population Pharmacokinetics of Ganciclovir in Allogeneic Hematopoietic Stem Cell Transplant Patients
Authors: Selby Philip R. , Heffernan Aaron J. , Yeung David , Warner Morgyn S. , Peake Sandra L. , Hahn Uwe , Wallis Steven C. , Mcwhinney Brett , Ungerer Jacobus P. J. , Shakib Sepehr , Roberts Jason A.
Published: February 2023

Treatment of cytomegalovirus (CMV) infection in allogeneic hematopoietic stem cell transplantation (alloHCT) patients with ganciclovir is complicated by toxicity and resistance. This study aimed to develop an intravenous ganciclovir population pharmacokinetic model for post-alloHCT patients and to determine dosing regimens likely to achieve suggested therapeutic exposure targets.
Population Pharmacokinetic and Pharmacodynamic Analysis of Valganciclovir for Optimizing Preemptive Therapy of Cytomegalovirus Infections in Kidney Transplant Recipients
Authors: Cojutti Pier Giorgio , Heffernan Aaron J. , Tängdén Thomas , Della Siega Paola , Tascini Carlo , Roberts Jason A. , Pea Federico
Published: February 2023

This study aimed to develop a population pharmacokinetic/pharmacodynamic (PK/PD) model of valganciclovir for preemptive therapy of cytomegalovirus (CMV) infection in kidney transplant patients. A population PK/PD model was developed with Monolix.
Critical Residues Involved in the Coassembly of L1 and L2 Capsid Proteins of Human Papillomavirus 16
Authors: Chen Jie , Wang Daning , Wang Zhiping , Wu Kunbao , Wei Shuangping , Chi Xin , Qian Ciying , Xu Yujie , Zhou Lizhi , Li Yuqian , Zhang Sibo , Li Tingting , Kong Zhibo , Wang Yingbin , Zheng Qingbing , Yu Hai , Zhao Qinjian , Zhang Jun , Xia Ningshao , Li Shaowei , Gu Ying
Published: February 2023

Over 200 types of HPV have been isolated, with several high-risk types correlated with the occurrence of cervical cancer. The HPV major capsid protein, L1, assembles into a T=7 icosahedral viral shell, and associates with the minor capsid protein, L2, which plays a critical role in the HPV life cycle.
Multiplex Assay for Simultaneous Detection of Antibodies against Crimean-Congo Hemorrhagic Fever Virus Nucleocapsid Protein and Glycoproteins in Ruminants
Authors: Hoste Alexis C. R. , Djadjovski Igor , Jiménez-Clavero Miguel Ángel , Rueda Paloma , Barr John N. , Sastre Patricia
Published: February 2023

Crimean-Congo hemorrhagic fever virus (CCHFV) causes Crimean-Congo hemorrhagic fever, which is one of the most important tick-borne viral diseases of humans and has recently been found in previously unaffected countries such as Spain. The disease is asymptomatic in infected animals but can develop into severe illness in humans.