bluuebunny/crossref_metadata_2025 huggingface dataset:
Continuum of maternal and newborn health in Sierra Leone: a 2019 national survey
Authors: Sserwanja Quraish , Mutisya Linet M. , Nuwabaine Lilian , Kamara Kassim , Mutebi Ronald K. , Musaba Milton W.
Published: August 2022

Introduction

Globally, Sierra Leone has some of the worst maternal and child health indicators. The situation is worsened by a dearth of evidence about the level of continuum of care, an evidence-based intervention aimed at reducing maternal and perinatal morbidity and mortality. Hence this study aimed to assess the level of and factors associated with continuum of maternal and newborn care in Sierra Leone.

Method

This study analyzed secondary data from the 2019 Sierra Leone Demographic Health Survey. Analysis was restricted to women who had a live birth in the 5 years preceding the survey (n = 7326). Complete continuum of care was considered when a woman reported having had at least eight antenatal care contacts, skilled birth attendance and mother and baby had at least one postnatal check-up. Bi-variable and multivariable logistic regression were performed using the statistical package for the social sciences software version 25.

Results

Only 17.9% (95% CI: 17.4–19.1) of the women utilized complete continuum of care for maternal and newborn health services in Sierra Leone. About 22% (95% CI: 21.3–23.1) utilized 8 or more antenatal care contacts, 88% (95% CI: 87.9–89.4) had skilled birth attendance while 90.7% (95% CI: 90.2–91.5) and 90.4% (95% CI: 89.9–91.2) of mothers and neonates utilized postnatal care respectively. Having started antenatal care within the first trimester (aOR 1.71, 95% CI: 1.46–2.00), being resident in the Southern region (aOR 1.85, 95% CI: 1.23–2.80), belonging to richer wealth quintile (aOR 1.76, 95% CI: 1.27–2.44), using internet (aOR 1.49, 95% CI: 1.12–1.98) and having no big problems seeking permission to access healthcare (aOR 1.34, 95% CI: 1.06–1.69) were significantly associated with utilization of continuum of care.

Conclusion

The overall completion of continuum of maternal care is low, with ANC being the lowest utilized component of continuum of care. These findings call for urgent attention for maternal health stakeholders to develop and implement tailored interventions prioritizing women empowerment, access to affordable internet services, timely initiation of ANC contacts, women in developed regions such as the Western and those from poor households.
Effect of goal-directed haemodynamic therapy guided by non-invasive monitoring on perioperative complications in elderly hip fracture patients within an enhanced recovery pathway
Authors: Lorente Juan V. , Reguant Francesca , Arnau Anna , Borderas Marcelo , Prieto Juan C. , Torrallardona Jordi , Carrasco Laura , Solano Patricia , Pérez Isabel , Farré Carla , Jiménez Ignacio , Ripollés-Melchor Javier , Monge Manuel I. , Bosch Joan
Published: August 2022

Background

Goal-directed haemodynamic therapy (GDHT) has been shown to reduce morbidity and mortality in high-risk surgical patients. However, there is little evidence of its efficacy in patients undergoing hip fracture surgery. This study aims to evaluate the effect of GDHT guided by non-invasive haemodynamic monitoring on perioperative complications in patients undergoing hip fracture surgery.

Methods

Patients > 64 years undergoing hip fracture surgery within an enhanced recovery pathway (ERP) were enrolled in this single-centre, non-randomized, intervention study with a historical control group and 12-month follow-up. Exclusion criteria were patients with pathological fractures, traffic-related fractures and refractures. Control group (CG) patients received standard care treatment. Intervention group (IG) patients received a GDHT protocol based on achieving an optimal stroke volume, in addition to a systolic blood pressure > 90 mmHg and an individualized cardiac index. No changes were made between groups in the ERP during the study period. Primary outcome was percentage of patients who developed intraoperative haemodynamic instability. Secondary outcomes were intraoperative arrhythmias, postoperative complications (cardiovascular, respiratory, infectious and renal complications), administered fluids, vasopressor requirements, perioperative transfusion, length of hospital stay, readmission and 1-year survival.

Results

In total, 551 patients (CG=272; IG=279) were included. Intraoperative haemodynamic instability was lower in the IG (37.5% vs 28.0%; p=0.017). GDHT patients had fewer postoperative cardiovascular (18.8% vs 7.2%; p < 0.001), respiratory (15.1% vs 3.6%; p<0.001) and infectious complications (21% vs 3.9%; p<0.001) but not renal (12.1% vs 33.7%; p<0.001). IG patients had less vasopressor requirements (25.5% vs 39.7%; p<0.001) and received less fluids [2.600 ml (IQR 1700 to 2700) vs 850 ml (IQR 750 to 1050); p=0.001] than control group. Fewer patients required transfusion in GDHT group (73.5% vs 44.4%; p<0.001). For IG patients, median length of hospital stay was shorter [11 days (IQR 8 to 16) vs 8 days; (IQR 6 to 11) p < 0.001] and 1-year survival higher [73.4% (95%CI 67.7 to 78.3 vs 83.8% (95%CI 78.8 to 87.7) p<0.003].

Conclusions

The use of GDHT decreases intraoperative complications and postoperative cardiovascular, respiratory and infectious but not postoperative renal complications. This strategy was associated with a shorter hospital stay and increased 1-year survival.

Trial registration

ClinicalTrials.gov NCT02479321.
A significant quantitative trait locus on chromosome Z and its impact on egg production traits in seven maternal lines of meat-type chicken
Authors: Ding Jiqiang , Ying Fan , Li Qinghe , Zhang Gaomeng , Zhang Jin , Liu Ranran , Zheng Maiqing , Wen Jie , Zhao Guiping
Published: August 2022

Background

Egg production is economically important in the meat-type chicken industry. To better understand the molecular genetic mechanism of egg production in meat-type chicken, genetic parameter estimation, genome-wide association analyses combined with meta-analyses, Bayesian analyses, and selective sweep analyses were performed to screen single nucleotide polymorphisms (SNPs) and other genetic loci that were significantly associated with egg number traits in 11,279 chickens from seven material lines.

Results

Yellow-feathered meat-type chickens laid 115 eggs at 43 weeks of age and white-feathered chickens laid 143 eggs at 60 weeks of age, with heritability ranging from 0.034–0.258. Based on meta-analyses and selective sweep analyses, one region (10.81–13.05 Mb) on chromosome Z was associated with egg number in all lines. Further analyses using the W2 line was also associated with the same region, and 29 SNPs were identified that significantly affected estimation of breeding value of egg numbers. The 29 SNPs were identified as having a significant effect on the egg number EBV in 3194 birds in line W2. There are 36 genes in the region, with glial cell derived neurotrophic factor, DAB adaptor protein 2, protein kinase AMP-activated catalytic subunit alpha 1, NAD kinase 2, mitochondrial, WD repeat domain 70, leukemia inhibitory factor receptor alpha, complement C6, and complement C7 identified as being potentially affecting to egg number. In addition, three SNPs (rs318154184, rs13769886, and rs313325646) associated with egg number were located on or near the prolactin receptor gene.

Conclusion

Our study used genomic information from different chicken lines and populations to identify a genomic region (spanning 2.24 Mb) associated with egg number. Nine genes and 29 SNPs were identified as the most likely candidate genes and variations for egg production. These results contribute to the identification of candidate genes and variants for egg traits in poultry.
Re-emerging threat of Trypanosoma cruzi vector transmission in El Salvador, update from 2018 to 2020
Authors: Rodríguez Marvin Stanley , Nitahara Yuko , Cornejo Michelle , Siliezar Kevin , Grande Rafael , González Ana , Tasaki Kotaro , Nakagama Yu , Michimuko Yu , Onizuka Yoko , Nakajima-Shimada Junko , Romero José Eduardo , Palacios José Ricardo , Arias Carmen Elena , Mejía William , Kido Yasutoshi , Cardona Alvarenga Ricardo
Published: August 2022

Background

Since the late twentieth century, Chagas disease gained global attention to suppress the vector burden as a main control strategy in endemic countries. In Central America, multi-national initiative successfully achieved significant reduction in the estimated disease prevalence as well as elimination of the region’s principal vector species at the time in 2012. While the last decade has witnessed significant changes in ecosystem—such as urbanization and replacement of the main vector species—that can possibly affect the vector’s habitation and residual transmission, the up-to-date vector burden in the region has not been evaluated thoroughly due to the cessation of active vector surveillance. The aim of this study was to update the risk of vector-borne Trypanosoma cruzi infection in El Salvador, the top Chagas disease-endemic country in Central America.

Methods

A nationwide vector survey was conducted in the domestic environment of El Salvador from September 2018 to November 2020. The selection of the houses for inspection was based on expert purposeful sampling. Infection for T. cruzi was examined by microscopic observation of the insects’ feces, followed by a species confirmation using PCR. The data were analyzed using R software version 4.1.3. Proportion estimates with 95% confidence intervals were inferred using the Jeffrey’s method provided under the epiR package.

Results

A total of 1529 Triatoma dimidiata was captured from 107 houses (infestation rate, 34.4%; 107/311) in all the fourteen departments of the country visited within the period; prevalence of T. cruzi infection was as high as 10% (153/1529). In the country, domestic T. dimidiata infestation was distributed ubiquitously, while T. cruzi infection rates varied across the departments. Five out of fourteen departments showed higher infection rates than the average, suggesting sporadic high-risk areas in the country.

Conclusions

Our comprehensive study revealed substantial T. cruzi infection of T. dimidiata across the country, indicating potential active transmission of the disease. Therefore, strengthened surveillance for both vector and human infection is required to truly eliminate the risk of T. cruzi transmission in Central America.
Impact of smart combinations of graphene oxide and micro/nanosized sulfur particles on soil health and plant biomass accumulation
Authors: Hammerschmiedt Tereza , Holatko Jiri , Huska Dalibor , Kintl Antonin , Skarpa Petr , Bytesnikova Zuzana , Pekarkova Jana , Kucerik Jiri , Mustafa Adnan , Radziemska Maja , Malicek Ondrej , Vankova Lenka , Brtnicky Martin
Published: August 2022

Background

Elemental sulfur (S0) is a cost-efficient fertilizer and the least rapidly utilizable source of S for soil microorganisms and plants. Its bacterial-mediated oxidation to sulfates is dependent on particle size. Finely formulated (micronized, nanosized) S0 exerts enhanced oxidation rate and benefit due to nutrient availability and crop nutrition efficiency. Graphene oxide (GO) affects soil properties both negatively and positively. A pot experiment was carried out with lettuce using soil supplemented with S0 in different composition, applied alone or in combination with GO. The following variants were tested: control, GO, micro-S0, micro-S0 + GO, nano-S0, nano-S0 + GO.

Results

Nanosized S0 improved most of enzyme activities (dehydrogenase, arylsulfatase, N-acetyl-β-d-glucosaminidase, β-glucosidase, phosphatase). However, respirations induced by d-glucose, protocatechuic acid, l-arginine were decreased. GO mitigated negative to neutral effect of micro-S0 in the soil pH, dehydrogenase and urease activity. Furthermore, micro-S0 positively affected basal respiration and respirations induced by d-trehalose and N-acetyl-β-d-glucosamine. Nano-S0 + GO improved plant biomass yield and enzyme activities. However, nano-S0 + GO significantly decreased all substate-induced respirations.

Conclusions

The benefit of soil treatment with nano-/micro-sized S0 and its combination with GO on soil biological parameters was partially demonstrated.

Graphical Abstract
Stakeholder perspectives on hiring teaching-focused faculty at research-intensive universities
Authors: Harlow Ashley N. , Buswell Natascha T. , Lo Stanley M. , Sato Brian K.
Published: August 2022

Background

Teaching-focused faculty positions have grown in popularity in higher education and provide novel opportunities to transform undergraduate science, technology, engineering, and mathematics (STEM) education. The University of California (UC) system employs a unique teaching-focused faculty position, officially called the Lecturer with Potential Security of Employment (L(P)SOE), with the working title called Professor of Teaching (PoT). The UC PoT position is a tenure-track position with teaching as the primary tenure expectation. We present findings from interviews with stakeholder faculty in STEM departments at three UC campuses to identify reasons for hiring PoT, capture accomplishments of PoT in their departments and disciplinary fields, and identify potential barriers to PoT success.

Results

Overall, this study highlights stakeholder’s perspectives on the value of teaching-focused faculty in research-intensive universities. Stakeholders described the goals for hiring Professors of Teaching, which included easing the burden of teaching responsibilities of the departments and adding consistency of instruction. While the stakeholders expressed that PoT were meeting the goals for being hired, they also identified many barriers for PoT being fully integrated and successful. The stakeholders expressed concern about unclear and unfair expectations related to tenure and promotion.

Conclusions

The findings point to a general undervaluing and underappreciation of teaching-focused faculty and suggest that in order for PoT to have a positive impact on STEM higher education, they need more support and inclusion from their colleagues and institutions.
Development of a simulation technical competence curriculum for medical simulation fellows
Authors: Ahmed Rami A. , Cooper Dylan , Mays Chassity L. , Weidman Chris M. , Poore Julie A. , Bona Anna M. , Falvo Lauren E. , Moore Malia J. , Mitchell Sally A. , Boyer Tanna J. , Atkinson S. Scott , Cartwright Johnny F.
Published: August 2022

Background and needs

Medical educators with simulation fellowship training have a unique skill set. Simulation fellowship graduates have the ability to handle basic and common troubleshooting issues with simulation software, hardware, and equipment setup. Outside of formal training programs such as this, simulation skills are inconsistently taught and organically learned. This is important to address because there are high expectations of medical educators who complete simulation fellowships. To fill the gap, we offer one way of teaching and assessing simulation technical skills within a fellowship curriculum and reflect on lessons learned throughout the process. This report describes the instructional designs, implementation, and program evaluation of an educational intervention: a simulation technology curriculum for simulation fellows.

Curriculum design

The current iteration of the simulation technical skill curriculum was introduced in 2018 and took approximately 8 months to develop under the guidance of expert simulation technology specialists, simulation fellowship-trained faculty, and simulation center administrators. Kern’s six steps to curriculum development was used as the guiding conceptual framework. The curriculum was categorized into four domains, which emerged from the outcome of a qualitative needs assessment. Instructional sessions occurred on 5 days spanning a 2-week block. The final session concluded with summative testing.

Program evaluation

Fellows were administered summative objective structured exams at three stations. The performance was rated by instructors using station-specific checklists. Scores approached 100% accuracy/completion for all stations.

Conclusions

The development of an evidence-based educational intervention, a simulation technical skill curriculum, was highly regarded by participants and demonstrated effective training of the simulation fellows. This curriculum serves as a template for other simulationists to implement formal training in simulation technical skills.
L-type voltage-dependent Ca2+ channels expression involved in pre-neoplastic transformation of breast cancer
Authors: Aguiar Flávia , Rhana Paula , Bloise Enrrico , Rodrigues Andreia Laura Prates , Ferreira Enio
Published: August 2022

Background

Intracellular Ca2+ levels can modulate several cellular functions, including proliferation and other processes found altered in neoplastic cells. Helping to maintain Ca2+ homeostasis, L-type voltage-dependent Ca2+ channels had its expression identified in neoplasias, including breast cancer. Invasive breast carcinoma of no special type, the most common classification of breast cancer, has ductal hyperplasia and ductal carcinoma in situ as its possible non-obligate precursors. This channel’s role in breast cancer development from these precursors has not been investigated. Evaluate protein expression and subcellular localization of CaV1.1, CaV1.2, and CaV1.3 in mammary epithelium without alteration and neoplastic and non-neoplastic ductal proliferative lesions through immunohistochemistry was the aim of this investigation.

Methods

In the present study, CaV1.1, CaV1.2, and CaV1.3 protein expression was evaluated by immunohistochemistry in breast without alteration and in proliferative non-neoplastic and neoplastic ductal epithelial lesions of the human breast.

Results

It was observed that CaV1.3 presented a reduction in nuclear expression at neoplastic lesions, in addition to an increase in cytoplasmic CaV1.1 expression. The analyses of membrane immunostaining showed that CaV1.2 and CaV1.3 had an increase of expression as the lesions progressed in the stages leading to invasive carcinomas.

Conclusions

Changes in protein expression and subcellular localization of these channels during the progression stages indicate that they may be involved in neoplastic transformation.
Radiographic aspects in individuals infected by human T-lymphotropic virus type 1 (HTLV-1) with joint pain
Authors: da Silva Carvalho João Marcos , de Araújo Campos Eugênia Maria Teixeira , Ferreira José Luiz Nunes , Carvalho Huliana Mourão , Carneiro Neto José Abraão , de Oliveira Carneiro Tássila , Carvalho Edgar Marcelino
Published: August 2022

Background

Joint pain in the absence or with little synovitis is observed in a large percentage of HTLV-1 infected subjects. As the virus infect CD4 + and CD8 + positive, macrophages and B cells an exaggerated production of pro-inflammatory cytokines is detected in these patients. However, the possible association of HTLV-1 infection with autoimmune diseases has not been documented definitively and the clinical characteristics of HTLV-1 associated arthropathy has not been defined. The objective this study is to describe clinic and radiographic features in HTLV-1-infected individuals with complaints of joint pain.

Methods

Cross-sectional study enrolling HTLV-1-infected individuals with chronic joint pain, aged up to 75 years, both genders and seronegative controls with osteoarthritis. All participants underwent conventional radiography of the hips, knees and ankles.

Results

Eighty-one HTLV-1 infected patients and 30 subjects with osteoarthritis participated in the study. Polyarticular and symmetrical arthritis prevailed in the HTLV-1 positive group (54%), while oligoarticular and asymmetrical (44%) were more common in controls (p < 0.05). The frequency of enthesophytes (90%) in HTLV-1-infected patients was greater than in the control group (73%) (p < 0.05). Radiographic features were similar in HTLV-1 carriers and in patients with probable or definite HTLV-1 associated myelopathy. The presence of enthesophytes in the absence of joint space reduction or osteophytes was only observed in HTLV-1-infected individuals (p < 0.001). Magnetic resonance imaging of the ankles of five HTLV-1-infected patients and five controls demonstrated a higher frequency of enthesitis, bursitis and osteitis in the HTLV-1 infected group.

Conclusion

HTLV-1-associated arthropathy is clinically characterized by symmetrical polyarthralgia and the main radiological finding is the presence of enthesophytes in the absence of osteophytes and joint space narrowing.
Age-related difficulty in post-intubation tracheal stenosis reconstruction: a comparative analysis of CO2-laser, resection and anastomosis, and costal cartilage grafting techniques
Authors: Ozkul Yilmaz , Songu Murat , Bayrak Asuman Feda , İşlek Akif
Published: August 2022

Background

Costal cartilage graft (CCG) sustains primary donor material for laryngotracheal reconstruction in patients with post-intubation tracheal stenosis (PITS). But, the elasticity and viability of CCG decrease elderly. This study was aimed to examine the age factor in PITS cases according to the treatment groups, especially in the tracheal reconstruction surgery with CCG group.

Methods

This retrospective study was designed. Patients with a diagnosis of PITS were enrolled. The hazard ratio was calculated with the Cox regression model to define independent risk factors for failure among the variables.

Results

Eighty-five patients diagnosed with post-intubation tracheal stenosis (PITS) were enrolled in the study. Restenosis developed in 19 (22.4%) patients. The failure rate in patients aged 40 years and older was 7.5 times higher on average compared to patients under 40 years of age (p= 0.004, 95%CI: 1.6–35.2). Additionally, age group ≥ 40 and CCG treatment group were a significant risk factors for surgical failure (p= 0.012,HR= 0.0003, 95% CI forHR= 0.0000006–0.173, andp< 0.001,HR= 0.001, 95%CI forHR= 0.000025–0.047, respectively).

Conclusions

Age and CCG group were detected as independent risk factors for surgical failure, possibly due viability of costal cartilage.
Madness and society in Britain
Authors: Ikkos George , Bouras Nick , Tyrer Peter
Published: August 2022

The fiftieth anniversary of the Royal College of Psychiatrists, and the publication of a detailed multidisciplinary social history of British psychiatry and mental health in recent decades have offered an opportunity to take a helicopter view and reflect on the relation between psychiatry and changing British society. We argue that the time has come to move on from the rhetoric of deinstitutionalisation and community mental healthcare to lead public debate and advocacy for the needs of the mentally ill in the new era of ‘meta-community psychiatry and mental healthcare’. We need to respond effectively to the increasing awareness of mental health problems across society, aiming for a pluralist, integrated and well-funded reform led by joint professional and patient interests which could be unstoppable if we all work together.
Shared Nearest Neighbors Approach and Interactive Browser for Network Analysis of a Comprehensive Non–Small-Cell Lung Cancer Data Set
Authors: Schmidt Stephanie T. , Akhave Neal , Knightly Ryan E. , Reuben Alexandre , Vokes Natalie , Zhang Jianhua , Li Jun , Fujimoto Junya , Byers Lauren A. , Sanchez-Espiridion Beatriz , Diao Lixia , Wang Jing , Federico Lorenzo , Forget Marie-Andree , McGrail Daniel J. , Weissferdt Annikka , Lin Shiaw-Yih , Lee Younghee , Suzuki Erika , Kovacs Jeffrey J. , Behrens Carmen , Wistuba Ignacio I. , Futreal Andrew , Vaporciyan Ara , Sepesi Boris , Heymach John V. , Bernatchez Chantale , Haymaker Cara , Cascone Tina , Zhang Jianjun , Bristow Christopher A. , Heffernan Timothy P. , Negrao Marcelo V. , Gibbons Don L. ,   the ICON Team
Published: August 2022

PURPOSE

Advances in biological measurement technologies are enabling large-scale studies of patient cohorts across multiple omics platforms. Holistic analysis of these data can generate actionable insights for translational research and necessitate new approaches for data integration and mining.

METHODS

We present a novel approach for integrating data across platforms on the basis of the shared nearest neighbors algorithm and use it to create a network of multiplatform data from the immunogenomic profiling of non–small-cell lung cancer project.

RESULTS

Benchmarking demonstrates that the shared nearest neighbors-based network approach outperforms a traditional gene-gene network in capturing established interactions while providing new ones on the basis of the interplay between measurements from different platforms. When used to examine patient characteristics of interest, our approach provided signatures associated with and new leads related to recurrence and TP53 oncogenotype.

CONCLUSION

The network developed offers an unprecedented, holistic view into immunogenomic profiling of non–small-cell lung cancer, which can be explored through the accompanying interactive browser that we built.
Experimentally Induced Hypoglycemia-associated Autonomic Failure in Humans: Determinants, Designs, and Drawbacks
Authors: Bisgaard Bengtsen Mads , Møller Niels
Published: August 2022

Context

Iatrogenic hypoglycemia remains one of the leading hindrances of optimal glycemic management in insulin-treated diabetes. Recurring hypoglycemia leads to a condition of hypoglycemia-associated autonomic failure (HAAF). HAAF refers to a combination of (i) impaired hormonal counterregulatory responses and (ii) hypoglycemia unawareness to subsequent hypoglycemia, substantially increasing the risk of severe hypoglycemia. Several studies since the 1990s have experimentally induced HAAF, yielding variable results.

Objective

The aim of this review was to assess the varying designs, clinical outcomes, potential assets, and drawbacks related to these studies.

Method

A systemic literature search was conducted on PubMed and Embase in winter 2021 to include all human studies attempting to experimentally induce HAAF. In different combinations, the search terms used were “hypoglycemia-associated autonomic failure,” “HAAF,” “hypoglycemia,” “recurring,” “recurrent,” “repeated,” “consecutive,” and “unawareness,” yielding 1565 publications. Inclusion criteria were studies that had aimed at experimentally inducing HAAF and measuring outcomes of hormonal counterregulation and awareness of hypoglycemia.

Results

The literature search yielded 27 eligible publications, of which 20 were successful in inducing HAAF while statistical significantly impairing both hormonal counterregulation and impairing awareness of hypoglycemia to subsequent hypoglycemia. Several factors were of significance as regards inducing HAAF: Foremost, the duration of antecedent hypoglycemia should be at least 90 minutes and blood glucose should be maintained below 3.4 mmol/L. Other important factors to consider are the type of participants, insulin dosage, and the risk of unintended hypoglycemia prior to the study.

Conclusion

Here we have outlined the most important factors to take into consideration when designing a study aimed at inducing HAAF, including to take into consideration other disease states susceptible to hypoglycemia, thus hopefully clarifying the field and allowing qualified studies in the future.
Exploring cell and tissue mechanics with optical tweezers
Authors: Català-Castro Frederic , Schäffer Erik , Krieg Michael
Published: August 2022

Cellular and tissue biosystems emerge from the assembly of their constituent molecules and obtain a set of specific material properties. To measure these properties and understand how they influence cellular function is a central goal of mechanobiology. From a bottoms-up, physics or engineering point-of-view, such systems are a composition of basic mechanical elements. However, the sheer number and dynamic complexity of them, including active molecular machines and their emergent properties, makes it currently intractable to calculate how biosystems respond to forces. Because many diseases result from an aberrant mechanotransduction, it is thus essential to measure this response. Recent advances in the technology of optical tweezers have broadened their scope from single-molecule applications to measurements inside complex cellular environments, even within tissues and animals. Here, we summarize the basic optical trapping principles, implementations and calibration procedures that enable force measurements using optical tweezers directly inside cells of living animals, in combination with complementary techniques. We review their versatility to manipulate subcellular organelles and measure cellular frequency-dependent mechanics in the piconewton force range from microseconds to hours. As an outlook, we address future challenges to fully unlock the potential of optical tweezers for mechanobiology.
Robotic communication with ants
Authors: Franks Nigel R. , Podesta Jacob A. , Jarvis Edward C. , Worley Alan , Sendova-Franks Ana B.
Published: August 2022

We used a robotic gantry to test the hypothesis that tandem running in the ant Temnothorax albipennis can be successful in the absence of trail laying by the leader. Pheromone glands were placed on a pin attached to a gantry. This set-up substituted for the leader of a tandem run. Neither the pin nor the glands touched the substrate and thus the ant following the robot was tracking a plume of airborne pheromones. The robot led individual workers from their current nest to a potential new one. The robotic gantry was programmed to allow for human intervention along its path to permit the following ant to stop and survey its surroundings and then catch up with its mechanical leader. The gantry then automatically tracked the precise route taken by each ant from the new nest back to the old one. Ants led by the robot were significantly more successful at finding their way home than those we carried to the new nest that had no opportunity to learn landmarks. The robot was programmed to take either a straight or a sinusoidal path to the new nest. However, we found no significant difference in the abilities of ants that had been led on such direct or sinuous paths to find their way home. Here, the robot laid no trail but our findings suggest that, under such circumstances, the following ant may lay a trail to substitute for the missing one.
Correlates of the Physical Activity Decline during Childhood
Authors: PEREIRA SARA , REYES ANA CAROLINA , CHAVES RAQUEL , SANTOS CARLA , VASCONCELOS OLGA , TANI GO , KATZMARZYK PETER T. , BAXTER-JONES ADAM , MAIA JOSÉ
Published: August 2022

Purpose

This study aimed to describe longitudinal trends in children’s moderate-to-vigorous physical activity (MVPA) and to investigate associations with individual, familial, and school characteristics.

Methods

A sample of 341 Portuguese children age 5–10 yr (173 girls) from six age cohorts was followed over 3 yr using a mixed-longitudinal design. Physical activity, body mass index (BMI), gross motor coordination, and musculoskeletal fitness were assessed annually. Information on socioeconomic status and school characteristics was collected and analyzed with mixed models.

Results

MVPA shows a similar declining trend in both sexes, but on average, boys exceeded the World Health Organization recommendations of 60 min·d−1. The best model showed that boys spend, on average, more time in MVPA than girls. Children with lower BMI are less prone to the decline in MVPA, whereas higher levels of musculoskeletal fitness were associated with lower declines in MVPA. Of all school characteristics, only playground dimension was related to MVPA decreasing trajectories.

Conclusions

MVPA systematically declines from 5 to 10 yr of age in both boys and girls, but boys remained more active than girls across the age range. The best predictors of MVPA decline are sex, BMI, musculoskeletal fitness, and school playground dimension.
Assessing the anticancer effects of metformin
Authors: Yunus Mohammed , Zaher Amr , Hussain Sajid , Alawami Karam Ali , Alfaraj Dhiyaa Jaber , Alqatari Ahmed Mohammed , Alsalim Morteda Jasim , Almissri Murtaja Zaki , Junaid Mohammed Abdul Lateef
Published: August 2022

Background: Metformin is an antihyperglycemic biguanide that is used as the first-line treatment for type 2 diabetes mellitus (T2DM). Metformin use helps control T2DM which is one of the many risk factors for cancer and is proposed to have multiple antagonistic actions against cancer cells. The epidemiology of cancers in Saudi Arabia are colorectal cancer (CRC) 14.4%, breast cancer 14.2%, thyroid cancer 10.2%, non-hodgkin lymphoma (NHL) 6.1%, leukemia 6%, and other cancers 49.2%.

We would like to assess the anticancer effect of metformin on various types of malignancies. 

Methods:  The 266 cancer patients diagnosed in 2018–2019 in King Fahd Hospital of the University (KFHU) were divided into non-diabetic and diabetic cancer patients (with or without metformin).  The data includes age, gender, body mass index (BMI), type of cancer with grades and stages, T2DM, with or without metformin, complications, and fate etc. of each case. 

Results: Out of 300, 266 were selected for the analysis. The results showed the statistical significance (p value 0.022) of metformin use on the cancer grade at diagnosis that favorably influences the morbidity/mortality.  

Conclusions: Metformin might have an anti-cancer effect on the grade of cancer at the time of diagnosis regardless of its dosage, and this might improve the prognosis of malignancy.
Women’s service in the armed forces during World War II in British and Soviet publications of the 1940s
Authors: Zalietok Nataliia
Published: August 2022

Artikli eesmärk on uurida ja võrrelda, kuidas Briti ja Nõukogude ajalookirjanduses on kajastatud ja iseloomustatud naiste osalemist Teises maailmasõjas. Autor jõuab järeldusele, et üks ühine joon Nõukogude ja Briti ajalookirjanduses on asjaolu, et mõlemad riigid asusid naiste osalust aktiivselt kajastama juba enne sõja lõppu, eesmärgiga värvata sõjateenistusse nii palju naisi kui võimalik. Sõja järel vähenes naiste tegevust sõjas kajastavate trükiste arv märgatavalt. Nõukogude ja Briti tekstides oli teisigi sarnaseid elemente, näiteks nende jutustav stiil ning tekstide sügav ideologiseeritus. Samas leidus ka erinevusi, näiteks kirjeldati sõjategevuses osalevaid naisi märgatavalt erinevalt.
Opaque Selling and Inventory Management in Vertically Differentiated Markets
Authors: Ren Hang , Huang Tingliang
Published: August 2022

Problem definition: We study the emerging practice of using opaque selling to dispose of leftover inventory in vertically differentiated markets. With this selling strategy, a firm offers a synthetic product (after the regular selling season) for which consumers do not know the exact identity until after purchase. Academic/practical relevance: This opaque-selling strategy is implemented in several industries—for example, travel and retail. However, its mechanisms are yet to be fully understood, as the extant literature considers other settings wherein opaque selling’s mechanisms do not carry over to ours. Methodology: We develop a game-theoretic model featuring a firm’s inventory and dynamic selling strategies and consumers’ strategic waiting. We characterize the optimal inventory levels, product offerings, and prices. Results: We find that, compared with last-minute selling (i.e., selling leftover inventory separately), opaque selling increases regular-season profits by softening intertemporal cannibalization from sales-season products to high-quality products sold in the regular season. However, it may decrease sales-season profits, as products with different qualities are probabilistically allocated to all purchasing consumers, irrespective of their valuations. We further demonstrate that these mechanisms are fundamentally different from those identified in the literature for other settings, and this contrast generates opposite recommendations as for the optimal usage of opaque selling. With endogenous inventory, interestingly, opaque selling is even more attractive, and it prompts the firm to procure fewer high-quality products than under last-minute selling. Managerial implications: We demonstrate the value of opaque selling as an inventory-clearance strategy in vertical markets. We show that a firm can further strengthen its profitability by combining opaque selling with inventory management. We also provide guidelines on managing inventory and illustrate the nontrivial impact of opaque selling.
Accelerated MM Algorithms for Inference of Ranking Scores from Comparison Data
Authors: Vojnović Milan , Yun Se-Young , Zhou Kaifang
Published: August 2022

Accelerated Algorithms for Ranking

Assigning ranking scores to items based on observed comparison data (e.g., paired comparisons, choice, and full ranking outcomes) has been of continued interest in a wide range of applications, including information search, aggregation of social opinions, electronic commerce, online gaming platforms, and more recently, evaluation of machine learning algorithms. The key problem is to compute ranking scores, which are of interest for quantifying the strength of skills, relevancies, or preferences, and prediction of ranking outcomes. One of the most popular statistical models of ranking outcomes is the Bradley–Terry model for paired comparisons and its extensions to choice and full ranking outcomes. In “Accelerated MM Algorithms for Inference of Ranking Scores from Comparison Data,” M. Vojnovic, S.-Y. Yun, and K. Zhou show that a popular MM algorithm for inference of ranking scores for generalized Bradley–Terry ranking models suffers a slow convergence issue, and they propose a new accelerated algorithm that resolves this shortcoming and can yield substantial convergence speedups.
Phase-drift cancellation for a phase-shifted signal on remote fiber link transfer using a phase-compensation technique
Authors: Zhai Wensheng , Xin Yunxia
Published: August 2022

A stable frequency transmission of a phase-shifted frequency signal in an optical fiber link is proposed and experimentally demonstrated using a phase-compensation technique, where phase drift produced by the mechanical stress and temperature acting on the optical fiber link is compensated based on feedback optical signal processing employing a phase modulator. An ultra-stable beam-forming signal conducive to the flexible distribution of phased array radar is obtained at the remote node. The experimental results implement a full 360° phase shift over a frequency range from 10 to 20 GHz through 200 km single-mode fiber, with Allan deviations of

∼

7.65

×

10

−
17

at average time of 1000 s and a root mean square jitter less than 0.39 ps. The proposed scheme is beneficial to implementation of high-resolution imaging in phased array radar.
Detection of the angle-of-arrival of an optical beam by means of
interference optical filters for free-space optical communication
Authors: Želudevičius Julijanas , Dubosas Giedrius , Švedas Vitas , Milaševičius Martynas , Regelskis Kęstutis
Published: August 2022

We propose a method for estimating the angle-of-arrival of an optical beam, which is based on angle-dependent properties of interference optical filters. One-filter and two-filter configurations for beam angle detection in one plane were investigated experimentally. By using off-the-shelf interference filters and a laser beam with a 4 nm broad spectrum at a 1030 nm center wavelength, an angle detection range of 1.6°–2.3° was achieved with an angle detection uncertainty standard deviation of

<

0.2

%

of the total beam angle detection range. The performance of the proposed beam angle detection method was compared with that of the segmented detector method under conditions of air turbulence. It was found that the proposed method is more resistant to turbulence-caused beam distortions and allows determination of the beam angle with higher precision.
Alleviated built-in electric field in the active region of AlGaN deep-ultraviolet light-emitting diodes with locally embedded p-i-n junctions
Authors: Ji Yongchen , Liu Mengran , Liu Chao
Published: August 2022

The strong polarization-induced electric field in the multi-quantum well region reduces the radiative recombination rates by separating the electron and hole wave functions, which is one of the most detrimental factors that is to blame for the low luminous efficiency of AlGaN deep-ultraviolet light-emitting diodes (DUV LEDs). In this work, we redesigned the active region by incorporating Si and Mg doping at the vicinity of the quantum wells, forming a series of embedded

p

−

i

−

n

junctions in the multi-quantum well region. The additional electric field induced by the fixed charges from the embedded doping-induced junctions can effectively compensate for the intrinsic polarization-induced electric fields in the quantum well region and give rise to the improved overlap of hole and electron wave function, hence enhancing the radiative recombination rates and the external quantum efficiency and optical power of DUV LEDs. The mechanism behind the alleviated polarization electric field is comprehensively discussed and analyzed. The embedded

p

−

i

−

n

junctions can also alter the band diagram structure of the active region, decrease the effective barrier heights for holes, and diminish the electron leakage into the

p

-type region. In addition, different thicknesses and doping concentrations of the embedded

p

- and

n

- layers were designed, and their influence on the performance of DUV LEDs was numerically analyzed. The proposed structure with embedded

p

−

i

−

n

junctions provides an alternative way to achieve efficient DUV LEDs.
Calibration of transverse ray and pupil aberrations for light field
cameras
Authors: Kwan Elliott , Hua Hong
Published: August 2022

The accuracy of reconstructing depth maps or performing digital refocusing in light field cameras depends largely on how well the spatial and angular samples of light rays can be obtained. Ray sample errors induced by optical aberrations in a light field camera may be digitally corrected using the ray tracing data when its nominal lens design is available. However, the most commonly nominal lens prescription is not accessible to end users. Additionally, even if available, due to tolerances in optomechanical design, the ray tracing data can be inaccurate. We propose a calibration method based on measurements of fiducial markers on a checkerboard for modeling the imaging properties of light field cameras. The calibration accounts for vignetting, transverse ray errors, as well as pupil aberration, and can be applied to light field camera modeling of arbitrary pupil sampling systems. We further demonstrate the utility of the method for calibrating a tri-aperture camera that captures simultaneous stereo views via artificially induced transverse ray errors.
High-performance compact athermal panoramic annular lens design with separated radial optical power
Authors: Zhu Chengxi , Wang Jia , Fei Wenhui , Fang Weidong , Bai Jian
Published: August 2022

A panoramic annular lens can provide abundant spatial information in real time with its compact and scalable structure. To deal with extreme temperature environments and to improve the utilization of an image plane, we propose a high-performance compact athermal panoramic annular lens with separated radial optical power. By introducing multiple free-form surfaces, the system achieves a field of view of

(

40

∘

∼

100

∘

)
×

360

∘

, an

f

-number of 2.2, and a total length of 40 mm. The modulation transfer function of the system’s full fields of view is greater than 0.5 at 200 lp/mm, and the distortion is less than 2.5%. It can work stably in the range of

−

30

∘

C

to 70°C. The proposed system is compact, athermal, and high-performing and has broad application prospects in the fields of visual positioning and biomedicine.
Global calibration method for non-overlapping cameras based on rigidly connected stereo targets
Authors: Zhu Zhenmin , Zheng Ying Qi , Li Wei , Zhang Jing , Zhao Yan , Wu Zi Wei
Published: August 2022

In complex field of view (FOV) environments, a single camera’s FOV measurement range is limited and cannot cover the entire object under test for global calibration. Multiple cameras are used mostly for large FOV environment measurements, but the traditional one- and two-dimensional targets used for global calibration in large FOV environments are prone to overlapping FOV. Furthermore, other large-sized targets are difficult to produce and process, and the laser projection method and plane mirror calibration methods are easily affected by the outdoor environment. To solve this problem, a non-common FOV binocular calibration method based on rigidly connected stereo targets is proposed. The calibration process is as follows: First, the rigidly connected target, which is composed of two plane targets with a checkerboard, is placed in front of the two cameras, and the vision sensor captures the corresponding sub-target image; then, the target is moved multiple times, and the transformation relationship between multiple vision sensors is obtained according to the spatial constraint characteristics of the rigidly connected target. Hence, the method overcomes the limitation of the non-overlapping FOV calibration method that relies on large measuring instruments. The experimental results show that the RMS error of the 13 mm distance is 0.16 mm. The proposed method is effective, simpler to operate than other methods, and does not rely on the constraint of complex targets. More importantly, this measurement method solves the difficult problem of measurement in non-public FOV, meeting the requirements of large FOV measurement ranges.
Surface metrology by multiple-wavelength coherent modulation imaging
Authors: Yi Jianji , Zhao Jiangtao , Wang Bingyang , Wang Yanfang , Zhang Fucai
Published: August 2022

With the rapid progress of advanced manufacturing, three-dimensional metrology techniques that are able to achieve nanometer spatial resolution and to capture fast dynamics are highly desired, for which a snapshot ability and a common-light-path setup are required. Commonly used off-axis holography and phase-shifting interferometry are short in fulfilling those requirements. We studied the suitability and performance of the coherent modulation imaging (CMI) method for metrology applications. Both transparent and reflective samples are measured in visible light experiments. Thanks to its ability to retrieve separate wavefronts at different wavelengths from a single measurement, CMI allows for attaining an enlarged range of measurement free from phase wrapping by utilizing the concept of synthetic wavelength. The CMI method fulfills well the requirements for advanced metrology and can be implemented at any wavelength. We expect it would be a powerful addition to the pool of advanced metrology tools.
Electromagnetic forces in the time domain
Authors: Kiselev Andrei , Achouri Karim , Martin Olivier J. F.
Published: August 2022

We look beyond the standard time-average approach and investigate optical forces in the time domain. The formalism is developed for both the Abraham and Minkowski momenta, which appear to converge in the time domain. We unveil an extremely rich – and by far unexplored – physics associated with the dynamics of the optical forces, which can even attain negative values over short time intervals or produce low frequency dynamics that can excite mechanical oscillations in macroscopic objects under polychromatic illumination. The magnitude of this beating force is tightly linked to the average one. Implications of this work for transient optomechanics are discussed.