bluuebunny/crossref_metadata_2025 huggingface dataset:
Personal experience and awareness of opioid overdose occurrence among peers and willingness to administer naloxone in South Africa: findings from a three-city pilot survey of homeless people who use drugs
Authors: Wilson Michael , Brumwell Amanda , Stowe M. J. , Shelly Shaun , Scheibe Andrew
Published: February 2022

Background

Drug overdoses occur when the amount of drug or combination of drugs consumed is toxic and negatively affects physiological functioning. Opioid overdoses are responsible for the majority of overdose deaths worldwide. Naloxone is a safe, fast-acting opioid antagonist that can reverse an opioid overdose, and as such, it should be a critical component of community-based responses to opioid overdose. However, the burden of drug overdose deaths remains unquantified in South Africa, and both knowledge about and access to naloxone is generally poor. The objective of this study was to describe the experiences of overdose, knowledge of responses to overdose events, and willingness to call emergency medical services in response to overdose among people who use drugs in Cape Town, Durban, and Pretoria (South Africa).

Methods

We used convenience sampling to select people who use drugs accessing harm reduction services for this cross-sectional survey from March to July 2019. Participants completed an interviewer-administered survey, assessing selected socio-demographic characteristics, experiences of overdose among respondents and their peers, knowledge about naloxone and comfort in different overdose responses. Data, collected on paper-based tools, were analysed using descriptive statistics and categorised by city.

Results

Sixty-six participants participated in the study. The median age was 31, and most (77%) of the respondents were male. Forty-one per cent of the respondents were homeless. Heroin was the most commonly used drug (79%), and 82% of participants used drugs daily. Overall, 38% (25/66) reported overdosing in the past year. Most (76%, 50/66) knew at least one person who had ever experienced an overdose, and a total of 106 overdose events in peers were reported. Most participants (64%, 42/66) had not heard of naloxone, but once described to them, 73% (48/66) felt comfortable to carry it. More than two-thirds (68%, 45/66) felt they would phone for medical assistance if they witnessed an overdose.

Conclusion

Drug overdose was common among participants in these cities. Without interventions, high overdose-related morbidity and mortality is likely to occur in these contexts. Increased awareness of actions to undertake in response to an overdose (calling for medical assistance, using naloxone) and access to naloxone are urgently required in these cities. Additional data are needed to better understand the nature of overdose in South Africa to inform policy and responses.
Global research trends on the links between the gut microbiome and cancer: a visualization analysis
Authors: Zyoud Sa’ed H. , Al-Jabi Samah W. , Amer Riad , Shakhshir Muna , Shahwan Moyad , Jairoun Ammar A. , Akkawi Maha , Abu Taha Adham
Published: February 2022

Background

Significant links between the microbiota and human health have emerged in the last 20 years. A correlation has recently been demonstrated between changes in the gut microbiota and the development of cancer. This study aimed to use bibliometric analysis of the published gut microbiome and cancer literature to present the research status and summarize the hotspots for frontier studies.

Methods

A literature search for research on the gut microbiome and cancer research from 2001 to 2020 was conducted using the Scopus database on 20 March 2021. VOSviewer software (version 1.6.16) was used to perform the visualization analysis.

Results

From 2001 to 2020, a total of 2061 publications were retrieved. Annual publication output grew from 10 in 2001 to 486 in 2020. The USA had the largest number of publications, making the largest contribution to the field (n  = 566, 27.46%). Before 2016, most studies focused on the ‘effect of probiotics on cancer’. The latest trends showed that ‘microbiota composition and gene expression’ and ‘host-microbiome interaction in cancer immunotherapy’ would be more concerned more widely in the future.

Conclusions

Research on ‘microbiota composition and gene expression’ and ‘host-microbiome interaction in cancer immunotherapy’ will continue to be the hotspot. Therefore, this study provides the trend and characteristics of the literature on the gut microbiota and cancer literature, which provided a useful bibliometric analysis for researchers to conduct further research.
Clinical utility of a pediatric hand exoskeleton: identifying users, practicability, and acceptance, and recommendations for design improvement
Authors: Lieber Jan , Dittli Jan , Lambercy Olivier , Gassert Roger , Meyer-Heim Andreas , van Hedel Hubertus J. A.
Published: February 2022

Background

Children and adolescents with upper limb impairments can experience limited bimanual performance reducing daily-life independence. We have developed a fully wearable pediatric hand exoskeleton (PEXO) to train or compensate for impaired hand function. In this study, we investigated its appropriateness, practicability, and acceptability.

Methods

Children and adolescents aged 6–18 years with functional limitations in at least one hand due to a neurological cause were selected for this cross-sectional evaluation. We characterized participants by various clinical tests and quantified bimanual performance with the Assisting Hand Assessment (AHA). We identified children whose AHA scaled score increased by ≥ 7 points when using the hand exoskeleton and determined clinical predictors to investigate appropriateness. The time needed to don each component and the number of technical issues were recorded to evaluate practicability. For acceptability, the experiences of the patients and the therapist with PEXO were evaluated. We further noted any adverse events.

Results

Eleven children (median age 11.4 years) agreed to participate, but data was available for nine participants. The median AHA scaled score was higher with PEXO (68; IQR: 59.5–83) than without (55; IQR: 37.5–80.5; p = 0.035). The Box and Block test, the Selective Control of the Upper Extremity Scale, and finger extensor muscle strength could differentiate well between those participants who improved in AHA scaled scores by ≥ 7 points and those who did not (sensitivity and specificity varied between 0.75 and 1.00). The median times needed to don the back module, the glove, and the hand module were 62, 150, and 160 s, respectively, but all participants needed assistance. The most critical failures were the robustness of the transmission system, the electronics, and the attachment system. Acceptance was generally high, particularly in participants who improved bimanual performance with PEXO. Five participants experienced some pressure points. No adverse events occurred.

Conclusions

PEXO is a safe exoskeleton that can improve bimanual hand performance in young patients with minimal hand function. PEXO receives high acceptance. We formulated recommendations to improve technical issues and the donning before such exoskeletons can be used under daily-life conditions for therapy or as an assistive device.

Trial registration Not appropriate
Intracranial internal carotid artery calcification is not predictive of future cognitive decline
Authors: Rahmani Farzaneh , Nguyen Marina , Chen Charles D. , McKay Nicole , Dincer Aylin , Joseph-Mathurin Nelly , Chen Gengsheng , Liu Jingxia , Orlowski Hilary L. P. , Morris John C. , Benzinger Tammie L. S.
Published: February 2022

Background

Intracranial internal carotid artery (ICA) calcification is a common incidental finding in non-contrast head CT. We evaluated the predictive value of ICAC (ICAC) for future risk of cognitive decline and compared the results with conventional imaging biomarkers of dementia.

Methods

In a retrospective observational cohort, we included 230 participants with a PET-CT scan within 18 months of a baseline clinical assessment and longitudinal imaging assessments. Intracranial ICAC was quantified on baseline CT scans using the Agatson calcium score, and the association between baseline ICA calcium scores and the risk of conversion from a CDR of zero in baseline to a persistent CDR > 0 at any follow-up visit, as well as longitudinal changes in cognitive scores, were evaluated through linear and mixed regression models. We also evaluated the association of conventional imaging biomarkers of dementia with longitudinal changes in cognitive scores and a potential indirect effect of ICAC on cognition through these biomarkers.

Results

Baseline ICA calcium score could not distinguish participants who converted to CDR > 0. ICA calcium score was also unable to predict longitudinal changes in cognitive scores, imaging biomarkers of small vessel disease such as white matter hyperintensities (WMH) volume, or AD such as hippocampal volume, AD cortical signature thickness, and amyloid burden. Severity of intracranial ICAC increased with age and in men. Higher WMH volume and amyloid burden as well as lower hippocampal volume and AD cortical signature thickness at baseline predicted lower Mini-Mental State Exam scores at longitudinal follow-up. Baseline ICAC was indirectly associated with longitudinal cognitive decline, fully mediated through WMH volume.

Conclusions

In elderly and preclinical AD populations, atherosclerosis of large intracranial vessels as demonstrated through ICAC is not directly associated with a future risk of cognitive impairment, or progression of imaging biomarkers of AD or small vessel disease.
The role of nephrologists in management of hypokalemic periodic paralysis: a case report
Authors: Li Julia , Moten Suha , Rauf Anis A.
Published: February 2022

Background

Hypokalemic periodic paralysis is a chronic condition characterized by sporadic attacks of weakness associated with acute hypokalemia. Attacks are typically associated with specific triggers, such as prolonged rest following exercise or consumption of a high-carbohydrate meal. Most commonly, this condition is caused by an autosomal dominant calcium channel mutation, and patients typically have an established family medical history of hypokalemic periodic paralysis. Long-term complications include the development of progressive proximal myopathy. Oral potassium chloride may be considered for the treatment of an acute attack, with administration of acetazolamide or dichlorphenamide as long-term prophylaxis. Nephrologists can play an important role in the recognition and treatment of previously undiagnosed hypokalemic periodic paralysis.

Case presentation

We summarize the case of a 19-year-old white man who presented to the emergency department with undiagnosed attacks of hypokalemic periodic paralysis, and who reported, at follow-up, improvement in the severity and frequency of attacks with dichlorphenamide.

Conclusions

This case demonstrates the crucial role nephrologists can play, not only in the diagnosis of hypokalemic periodic paralysis, but also in the ongoing management of this condition. Patients should be advised to regularly follow up with their nephrology team for evaluation due to the risk of developing myopathy.
Sanitary safety of the 2021 French Intensive Care Society medical conference: a case/control study
Authors:   SRLF Trial Group, Boelle Pierre-Yves , Decormeille Guillaume , Hermann Bertrand , Heming Nicholas , Jacq Gwenaelle , Kamel Toufik , Lascarrou Jean-Baptiste , Maury Eric , Papazian Laurent , Piton Gael , Poiroux Laurent , Ramillon Julien , Rouze Anahita
Published: February 2022

Background

In-person mass gathering events (MGE) are returning after a period of restrictions, yet few prospective scientific evaluations of their safety are available.

Methods

Prospective observational study, including both attendees of the French Intensive Care Society (FICS) annual meeting held in Paris between June the 9th and June the 11th, 2021 and matched controls (healthcare professionals who stayed in the ICU during the conference). SARS-CoV-2 lateral flow test was performed on day 7. Follow-up occurred until day 21.

Results

Out of the 1824 healthcare professionals attending the congress (all of which fulfilled legal requirements: 7 days or more following a second dose of vaccine or a negative PCR test performed within less than 72 h), 520 (28.5%) agreed to participate. Follow-up data were received for 216 (41.5%) out of the 520 included attendees, and for 191 matched controls. No positive SARS-CoV-2 lateral flow test was reported in the attendees or in the matched controls. The probability of SARS-CoV-2 infection during the MGE was less than 1.7% in the attendees (95% confidence interval [0;1.7%]), less than 2% in the controls (95%CI [0;2%]) and the difference in probabilities of infection was less than 1.9% (95% CI [0;1.9%]).

Conclusion

During a low incidence period, in this population of congress attendees screened for SARS-CoV-2 by a lateral flow test at day 7, no positive cases could be documented, no concomitant infection occurred in the matched controls; suggesting no extra risk of infection during the MGE.

Trial Registration: ClinicalTrial.gov, #NCT04918160.
A Capra hircus chromosome 19 locus linked to milk production influences mammary conformation
Authors: Jiang Andrew , Ankersmit-Udy Alex , Turner Sally-Anne , Scholtens Megan , Littlejohn Mathew D. , Lopez-Villalobos Nicolas , Proser Colin G. , Snell Russell G. , Lehnert Klaus
Published: February 2022

Background

Economically important milk production traits including milk volume, milk fat and protein yield vary considerably across dairy goats in New Zealand. A significant portion of the variation is attributable to genetic variation. Discovery of genetic markers linked to milk production traits can be utilised to drive selection of high-performance animals.

A previously reported genome wide association study across dairy goats in New Zealand identified a quantitative trait locus (QTL) located on chromosome 19. The most significantly associated single nucleotide polymorphism (SNP) marker for this locus is located at position 26,610,610 (SNP marker rs268292132). This locus is associated with multiple milk production traits including fat, protein and volume. The predicted effect of selection for the beneficial haplotype would result in an average production increase of 2.2 kg fat, 1.9 kg protein and 73.6 kg milk yield.

An outstanding question was whether selection for the beneficial allele would co-select for any negative pleiotropic effects. An adverse relationship between milk production and udder health traits has been reported at this locus. Therefore, a genome wide association study was undertaken looking for loci associated with udder traits.

Results

The QTL and production associated marker rs268292132 was identified in this study to also be associated with several goat udder traits including udder depth (UD), fore udder attachment (FUA) and rear udder attachment (RUA). Our study replicates the negative relationship between production and udder traits with the high production allele at position 19:26,610,610 (SNP marker rs268292132) associated with an adverse change in UD, FUA and RUA.

Conclusions

Our study has confirmed the negative relationship between udder traits and production traits in the NZ goat population. We have found that the frequency of the high production allele is relatively high in the NZ goat population, indicating that its effect on udder conformation is not significantly detrimental on animal health. It will however be important to monitor udder conformation as the chromosome 19 locus is progressively implemented for marker assisted selection. It will also be of interest to determine if the gene underlying the production QTL has a direct effect on mammary gland morphology or whether the changes observed are a consequence of the increased milk volume.
Analytical Quality by Design, Life Cycle Management, and Method Control
Authors: Verch Thorsten , Campa Cristiana , Chéry Cyrille C. , Frenkel Ruth , Graul Timothy , Jaya Nomalie , Nakhle Bassam , Springall Jeremy , Starkey Jason , Wypych Jette , Ranheim Todd
Published: February 2022

Analytical methods are utilized throughout the biopharmaceutical and vaccines industries to conduct research and development, and to help control manufacturing inputs and outputs. These analytical methods should continuously provide quality data to support decisions while managing the remaining of risk and uncertainty. Analytical quality by design (AQbD) can provide a systematic framework to achieve a continuously validated, robust assay as well as life cycle management. AQbD is rooted in ICH guidelines Q8 and Q9 that were translated to the analytical space through several white papers as well as upcoming USP 1220 and ICH Q14. In this white paper, we expand on the previously published concepts of AQbD by providing additional context for implementation in relation to ICH Q14. Using illustrative examples, we describe the AQbD workflow, its relation to traditional approaches, and potential pathways for ongoing, real-time verification. We will also discuss challenges with respect to implementation and regulatory strategies.
A Global Definition of Patient Blood Management
Authors: Shander Aryeh , Hardy Jean-Francois , Ozawa Sherri , Farmer Shannon L. , Hofmann Axel , Frank Steven M. , Kor Daryl J. , Faraoni David , Freedman John ,   Collaborators
Published: February 2022

While patient blood management (PBM) initiatives are increasingly adopted across the globe as part of standard of care, there is need for a clear and widely accepted definition of PBM. To address this, an expert group representing PBM organizations from the International Foundation for Patient Blood Management (IFPBM), the Network for the Advancement of Patient Blood Management, Haemostasis and Thrombosis (NATA), the Society for the Advancement of Patient Blood Management (SABM), the Western Australia Patient Blood Management (WAPBM) Group, and OnTrac (Ontario Nurse Transfusion Coordinators) convened and developed this definition: “Patient blood management is a patient-centered, systematic, evidence-based approach to improve patient outcomes by managing and preserving a patient’s own blood, while promoting patient safety and empowerment.” The definition emphasizes the critical role of informed choice. PBM involves the timely, multidisciplinary application of evidence-based medical and surgical concepts aimed at (1) screening for, diagnosing, and appropriately treating anemia; (2) minimizing surgical, procedural, and iatrogenic blood losses and managing coagulopathic bleeding throughout the care; and (3) supporting the patient while appropriate treatment is initiated. We believe that having a common definition for PBM will assist all those involved including PBM organizations, hospital administrators, individual clinicians, and policy makers to focus on the appropriate issues when discussing and implementing PBM. The proposed definition is expected to continue to evolve, making this endeavor a work in progress.
Application of Nonhuman Primate Models in the Studies of Pediatric Anesthesia Neurotoxicity
Authors: Wang Cheng , Liu Shuliang , Liu Fang , Bhutta Adnan , Patterson Tucker A. , Slikker William
Published: February 2022

Numerous animal models have been used to study developmental neurotoxicity associated with short-term or prolonged exposure of common general anesthetics at clinically relevant concentrations. Pediatric anesthesia models using the nonhuman primate (NHP) may more accurately reflect the human condition because of their phylogenetic similarity to humans with regard to reproduction, development, neuroanatomy, and cognition. Although they are not as widely used as other animal models, the contribution of NHP models in the study of anesthetic-induced developmental neurotoxicity has been essential. In this review, we discuss how neonatal NHP animals have been used for modeling pediatric anesthetic exposure; how NHPs have addressed key data gaps and application of the NHP model for the studies of general anesthetic-induced developmental neurotoxicity. The appropriate application and evaluation of the NHP model in the study of general anesthetic-induced developmental neurotoxicity have played a key role in enhancing the understanding and awareness of the potential neurotoxicity associated with pediatric general anesthetics.
Development of the mammalian main olfactory bulb
Authors: Tufo Candida , Poopalasundaram Subathra , Dorrego-Rivas Ana , Ford Marc C. , Graham Anthony , Grubb Matthew S.
Published: February 2022

The mammalian main olfactory bulb is a crucial processing centre for the sense of smell. The olfactory bulb forms early during development and is functional from birth. However, the olfactory system continues to mature and change throughout life as a target of constitutive adult neurogenesis. Our Review synthesises current knowledge of prenatal, postnatal and adult olfactory bulb development, focusing on the maturation, morphology, functions and interactions of its diverse constituent glutamatergic and GABAergic cell types. We highlight not only the great advances in the understanding of olfactory bulb development made in recent years, but also the gaps in our present knowledge that most urgently require addressing.
Pediatric Cardiopulmonary Exercise Testing: Interoperability Through Domain Analysis Modeling and a National Survey
Authors: COOPER DAN M. , BAR-YOSEPH RONEN , LIEM ROBERT I. , KEENS THOMAS G. , MCCOLLEY SUSANNA A. , RADOM-AIZIK SHLOMIT
Published: February 2022

Purpose

The electronic health record, data science advances, and dynamic environmental and infectious threats to child health highlight the need for harmonized and interoperable approaches to pediatric cardiopulmonary exercise testing (CPET). Accordingly, we developed a terminology harmonization in exercise medicine and exercise science domain analysis model (THEMES DAM) to structure CPET data elements.

Methods

THEMES DAM identified 114 data elements, including participant information, calibration, equipment, protocols, laboratory personnel, encouragement strategies, and analysis procedures. We used the THEMES DAM, vetted by the international data standards organization HL7, to construct a current-state survey of pediatric CPET centers in the United States. Forty-eight of 101 centers responded to a questionnaire covering seven major topic areas (38 items).

Results

Centers predominantly performed between 100 and 500 tests annually. Cardiac disease represented 55% of referrals. Almost all centers calibrated gas concentrations and flow daily, but 42% never calibrated their treadmill or cycle ergometers. All centers measured V̇O2peak

but calculated differently. Centers used a variety of protocols (e.g., for treadmill: 61%, Bruce; 43%, modified Bruce; 59%, other); 44% calculated CPET slopes from submaximal portions of CPET (e.g., V̇O2-HR). All centers verbally encouraged participants, but only 40% used a standardized approach. The interpretation of CPET was done by physicians (60%), exercise physiologists (25%), exercise technicians (10%), nurses (1%), or others (4%). Ninety-one percent would agree to collaborate in multicenter research, 89% to establish dynamic reference values, and 83% to better interpret CPET.

Conclusions

The survey data and the implementation of THEMES DAM could accelerate interoperability across multiple centers. This would facilitate a nimble approach to create pediatric reference values responsive to the constantly changing health environment and stimulate novel approaches to CPET research and clinical application.
PressPurt: network sensitivity to press perturbations under interaction uncertainty
Authors: Koslicki David , Gibbon Dana , Novak Mark
Published: February 2022

While the use of networks to understand how complex systems respond to perturbations is pervasive across scientific disciplines, the uncertainty associated with estimates of pairwise interaction strengths (edge weights) remains rarely considered. Mischaracterizations of interaction strength can lead to qualitatively incorrect predictions regarding system responses as perturbations propagate through often counteracting direct and indirect effects.

Here, we introduce PressPurt, a computational package for identifying the interactions whose strengths must be estimated most accurately in order to produce robust predictions of a network's response to press perturbations. The package provides methods for calculating and visualizing these edge-specific sensitivities (tolerances) when uncertainty is associated to one or more edges according to a variety of different error distributions. The software requires the network to be represented as a numerical (quantitative or qualitative) Jacobian matrix evaluated at stable equilibrium.

PressPurt is open source under the MIT license and is available as both a Python package and an R package hosted at https://github.com/dkoslicki/PressPurt and on the CRAN repository https://CRAN.R-project.org/package=PressPurt.
Effect of Aloe vera extract in post-burn skin repair in rats
Authors: Aulia Lusiana , Pane Yunita Sari
Published: February 2022

Background: Burn injury is a global health problem that is most often caused by heat. Burn injury can cause high morbidity and mortality and requires high cost. Therefore, the use of plants as herbal medicine has the potential to be developed in Indonesia. Aloe vera contains various active ingredients that help the wound healing process, such as glucomannan and acemannan which have the effects on the proliferation of macrophages, and fibroblasts, and re-epithelialization. This study aimed to determine the effect of Aloe vera extract in repairing post-burn skin in rats that was analyzed from the number of macrophages and fibroblasts, and epidermal thickness.

Methods: This is an experimental study with a posttest-only control group design using 54 Rattus norvegicus Wistar strain rats. The sampling method was simple random sampling consisting of 3 groups, i.e., I. standard group, which were normal rats; II. negative control group, which were given second-degree burns and treated with gel base (without Aloe vera extract); III. treatment groups, which were given second-degree burns and treated with Aloe vera extract gel. Each group was subdivided into three smaller groups (n = 6) according to the time the lesions were evaluated. Skin tissue samplings were carried out on day 3, 14, and 21 after injury to observe the number of macrophages and fibroblasts, and epidermal thickness.

Results: There were significant differences in the mean number of macrophages, number of fibroblasts, and epidermal thickness in all groups (p<0.05).

Conclusion: Aloe vera extract gel could accelerate the healing process of burns in rats.
Comparative study of the effect on the neuroendocrine-immune complex and metabolism of drinking monotherapy with Naftussya water and therapy supplemented with “Myroslava” and “Khrystyna” mineral waters
Authors: Hrytsak Myroslava , Popovych Dariya , Badiuk Nataliya , Hrytsan Ivanna , Żukow Xawery
Published: February 2022

Background. Earlier in an experiment on rats, we showed that the newly created sulfate-chloride sodium-magnesium drinking mineral waters of Truskavets’ spa have neuroendocrine and metabolic effects significantly different from daily water. Adhering to the principle "From experiment to clinic", we continued research in this direction with the participation of patients of the resort. Materials and Methods. The object of clinical-physiological observation were 34 men aged 23-70 years, who underwent rehabilitation treatment of chronic cholecystitis and pyelonephritis in remission in the Truskavets resort. The examination was performed twice, before and after a 7-10-day course of balneotherapy. All patients received bioactive water Naftussya, however, 11 men additionally drank water "Khrystyna", and the other 11 men - water "Myroslava". The subject of the study were the parameters of the neuroendocrine-immune complex and metabolism. Results. The complex balneotherapy by interval use of sulfate-chloride sodium-magnesium mineral waters with Naftusya water causes significant changes in the constellation of neuroendocrine, metabolic and immune parameters, which are different from the effects of Naftusya water monotherapy. Own effects of mineral waters are estimated by modeling. In general, the effects are physiologically favorable and have a normalizing nature. Conclusion. The newly created sulfate-chloride sodium-magnesium drinking mineral waters of Truskavets resort have favorable neuroendocrine, metabolic and immune effects on patients with chronic cholecystitis and pyelonephritis.
Left atrial myxoma with concomitant coronary artery stenosis: comprehensive diagnosis and treatment
Authors: Ciechański Erwin , Ciechański Krystian , Szponar Jarosław , Kołątaj Piotr , Szczasny Marcin , Głowniak Andrzej , Szumiło Justyna
Published: February 2022

A 69-year-old patient was admitted to the Department of Cardiology due to an accidental finding on a chest X-ray, enlarged heart outline, accompanied by worsening of heart failure to NYHA II with LVEF, about 30%. In the X-ray description, an enlargement of the left atrium silhouette with local calcifications. The patient underwent TTE, confirming the presence of a pedunculated tumor of the left atrium attached to the ceiling measuring 3.5x3.5x2.2 cm. Due to the ischemic heart disease manifestation patient uderwent coronarography confirming the presence of single-vessel coronary artery disease with changes in the middle segment of the LAD. Patient was treated with CABG LIMA-LAD surgery and removeal the left atrial tumor. Post operation tissue material prooved the preseance of left atrium myxoma. The postoperative course was uneventful, the patient was discharged home.
Intervencionismo neoliberal en Buenos Aires: mercantilización, propiedad privada y suelo para el sector inmobiliario
Authors: Pirez Pedro Tomas
Published: February 2022

El suelo es el componente esencial para la producción de la ciudad. En Buenos Aires la oferta de suelo vacante adecuado para desarrollar proyectos inmobiliarios de alta rentabilidad depende, mayormente, de la incorporación al mercado de propiedades fiscales y suelo ocupado irregu­larmente en las urbanizaciones populares. Para ello interviene el Estado con dos orientaciones fundamentales: mercantilización y propiedad privada. Desde el año 2007 se concreta en dos políticas cuya finalidad es transferir (privatizar) suelo a los operadores inmobiliarios, tanto desde propiedades fiscales como por la incorporación al mercado de suelo ocupado irregularmente por sectores populares. El texto analiza el proceso de reurbanización de la Villa 31-31bis y las políticas de venta de suelo público.
Gender, Race, and Network Advantage in Organizations
Authors: Castilla Emilio J.
Published: February 2022

Universities and colleges often engage in initiatives aimed at enrolling students from diverse demographic groups. Although substantial research has explored the impact of such diversity initiatives, less understood is the extent to which certain application strategies may continue to favor historically privileged groups, especially white men, as they seek admission to selective programs. With this study, I begin to address this gap by investigating the gender and racial implications of application endorsements—a common, often informal, network practice of signaling support for certain applicants that is shown to significantly boost an applicant’s chances of admission. Using unique data on the applicants and matriculants to a full-time MBA program at one elite U.S. business school, I first assess whether the endorsement advantage differs across demographic groups. Building on the social networks, selection, and inequality literatures, I then identify and test three key theoretical mechanisms by which the endorsement process may potentially benefit white men more than women and racial minorities. Although I do not find evidence in the studied program that the application endorsement is valued differently by key admissions officers or that it provides a different quality signal depending on the applicant’s gender or race, I do find that white men are significantly more likely than women and minorities to receive application endorsements. I conclude by discussing the implications of this study for understanding how gender and racial differences in accessing advantageous (often informal) network processes may undermine organizational efforts to achieve demographic equality and diversity.

Funding: Financial support from the James S. Hardigg (1945) Work and Employment Fund and the MIT Sloan School of Management is gratefully acknowledged.
Relational practice: Behaviour and culture
Authors: Knightsmith Pooky
Published: February 2022

When we put relationships at the heart of all we do in schools then everyone benefits – vulnerable children, their peers, and the adults working with them. Dr Pooky Knightsmith looks at how
The climate crisis, the curriculum and CPD
Authors: Dave Heena
Published: February 2022

The role of school leadership in responding to the environmental challenges of our generation is crucial – and will include ensuring high-quality teacher support and CPD. Heena Dave advises
Taking a new look at men's health
Authors: Rashid Saheed
Published: February 2022

A new year often comes with many resolutions – but for 2022, Saheed Rashid, Managing Director at BXTA urges men to take action over their health and make positive lifestyle changes
Parental Obstacles During Distance Learning Mathematics in Indonesia: A Phenomenology Study
Authors: Isnawan Muhamad Galang , Suryadi Didi , Turmudi Turmudi , Marfuah Marfuah
Published: February 2022

The Coronavirus disease (COVID-19) pandemic has caused an inevitable shift from face-to-face to distance learning, a phenomenon known as panic-gogy. Parents are the main students’ companions while studying at home. Although various studies show the constraints in this condition, few employ phenomenology that accurately describes people’s experience regarding a situation. Therefore, this study aimed to describe parents’ experience during distance learning mathematics using a phenomenology approach. The participants comprised 71 35-50-year-old parents of junior high school students. A Google form with open-ended questions was used as the main instrument in data collection. Data were analyzed using NVivo-12-assisted thematic analysis in coding, while source triangulation was used to strengthen the data trustworthiness. The results showed that students did not learn the content well due to poor explanations by the teacher. Furthermore, they did not study well at home due to signal constraints and quota limitations. This study recommends blended learning by combining limited face-to-face and online learning.
Computational Optical Sensing and Imaging 2021: introduction to the feature issue
Authors: Ke Jun , Alieva Tatiana , Oktem Figen S. , Silveira Paulo E. X. , Wetzstein Gordon , Willomitzer Florian
Published: February 2022

This feature issue includes two reviews and 34 research papers that highlight recent works in the field of computational optical sensing and imaging. Many of the works were presented at the 2021 Optica (formerly OSA) Topical Meeting on Computational Optical Sensing and Imaging, held virtually from 19 July to 23 July 2021. Papers in the feature issue cover a broad scope of computational imaging topics, such as microscopy, 3D imaging, phase retrieval, non-line-of-sight imaging, imaging through scattering media, ghost imaging, compressed sensing, and applications with new types of sensors. Deep learning approaches for computational imaging and sensing are also a focus of this feature issue.
Dynamic polarization-insensitive BOTDA in direct-detection OFDM with CNN-based BFS extraction
Authors: Qi Di , Li Jingyu , Guan Xun , Chan Chun-Kit
Published: February 2022

We propose a dynamic polarization-insensitive Brillouin optical time domain analyzer (D/PI-BOTDA) with orthogonal frequency division multiplexing (OFDM) based on intensity-modulated direct-detection (IM-DD). A polarization-division-multiplexed (PDM) pump signal enables polarization diversity of the stimulated Brillouin scattering while a multi-frequency OFDM probe signal realizes dynamic sensing with single-shot transmission. We experimentally demonstrated distributed temperature sensing along a total 940-meter fiber with a temperature sensing coefficient of 1.2°C/MHz. The experimental results indicated a remarkable suppression of Brillouin gain fluctuation up to 4.38 times compared to the case without polarization diversity. To facilitate the Brillouin frequency shift (BFS) extraction process, we also implement a CNN-based BFS extraction method with SE-Res2Net block. The adopted algorithm achieves a higher accuracy than conventional curve fitting method, with a 10-time enhancement in the time efficiency.
Toroidal dipole resonances by a sub-wavelength all-dielectric torus
Authors: Liu Liang , Ge Lixin
Published: February 2022

Electromagnetic toroidal excitations open up a new avenue for strong light-matter interactions. Although toroidal dipole resonances (TDRs) based on artificial meta-molecules were reported intensely, the TDRs supported in a single dielectric particle remain largely unknown. In this work, we show that an all-dielectric sub-wavelength torus can support a dominant TDR. The magnetic field can be enhanced greatly, and it shows a “vortex-like” configuration in the torus, confirming the toroidal excitation. The evolutions of the TDRs due to the geometrical parameters, dielectric permittivity, and polarization are discussed. It is found that the toroidal excitation is achieved mainly for TM polarization, while the anapole state is uncovered for TE polarization. This work suggests a new strategy for toroidal excitations based on a simple dielectric resonator.
Effect of porosity on thickness uniformity of MgF2 films on spherical substrates
Authors: Liu Cunding , Guo Qinmin , Wei Ming , Ai Wanjun , Xu Xu
Published: February 2022

Simulation based on Knudsen’s law shows that film thickness uniformity above 99% can be realized on spherical substrates with optimized profiles of shadowing masks. However, a type of optical thickness nonuniformity is revealed when the masks are applied for thickness correction of MgF2 films experimentally. The optical thickness nonuniformity depends on steepness of the spherical surfaces and reaches 5% approximately for surfaces with CA/RoC = 1.22. Porosity of the MgF2 film is superimposed on Knudsen’s law to interpret the optical thickness nonuniformity. For theoretical simulation, the influence of porosity on optical thickness distribution is characterized by a new parameter that describes nonlinear dependence of deposition rate on cosine function of molecular injection angles in Knudsen’s law. Utilizing the optimized deposition model, optical thickness uniformity of MgF2 films approaching to or above 99% has been achieved for surfaces of different steepness in a single coating run.
Phase locking of squeezed vacuum generated by a single-pass optical parametric amplifier
Authors: Taguchi Yoshitaka , Oguchi Kenichi , Xu Zicong , Cheon Donguk , Takahashi Shun , Sano Yuki , Harashima Fumiya , Ozeki Yasuyuki
Published: February 2022

In high-precision optical measurements, squeezed vacuum states are a promising resource for reducing the shot noise. To utilize a squeezed vacuum, it is important to lock the phase of the local oscillator (LO) to the squeezed light. The coherent control sideband (CCSB) scheme has been established for the precise phase locking, while the previous CCSB scheme was designed for the squeezed vacuum generated with an optical parametric oscillator (OPO). Thus the previous CCSB scheme is not applicable to squeezing by a single-pass optical parametric amplifier (OPA), which is attractive for generating broadband squeezed vacuum states. In this study, we propose a variant of CCSB scheme, which is applicable to the squeezing by single-pass OPA. In this scheme, we inject pump light and frequency-shifted signal light into an OPA crystal in the same way as the previous CCSB scheme. The parametric process in the OPA crystal generates a squeezed vacuum, amplifies the signal light, generates an idler light, and causes the pump depletion reflecting the interference of the amplified signal light and the idler light. Through the lock-in detection of the pump depletion, we can phase-lock the injected signal light to the pump light. Then, after the heterodyne detection of the signal and the idler light, we get the error signal of LO and realize the precise phase locking of LO to the squeezed quadrature. We show the feasibility of the proposed scheme by deriving the signal-to-noise ratio (SNR) of the modulated pump signal. We experimentally demonstrate the proposed scheme on pulsed squeezing by a single-pass OPA.
Phase-shifting algorithms with known and unknown phase shifts: comparison and hybrid
Authors: Chen Yuchi , Kemao Qian
Published: February 2022

The phase-shifting interferometry has been intensively studied for more than half a century, and is still actively investigated and improved for more demanding precision measurement requirements. A proper phase-shifting algorithm (PSA) for phase extraction should consider various error sources including (i) the phase-shift errors, (ii) the intensity harmonics, (iii) the non-uniform phase-shift distributions and (iv) the random additive intensity noise. Consequently, a large pool of PSAs has been developed, including those with known phase shifts (abbreviated as kPSA) and those with unknown phase shifts (abbreviated as uPSA). While numerous evaluation works have been done for the kPSAs, there are very few for the uPSAs, making the overall picture of the PSAs unclear. Specifically, there is a lack of (i) fringe pattern parameters’ restriction analysis for the uPSAs and (ii) performance comparison within the uPSAs and between the uPSAs and the kPSAs. Thus, for the first time, we comprehensively evaluated the pre-requisites and performance of four representative uPSAs, the advanced iterative algorithm, the general iterative algorithm (GIA), the algorithm based on the principal component analysis and the algorithm based on VU factorization, and then compare the uPSAs with twelve benchmarking kPSAs. From this comparison, the demand for proper selection of a kPSA, and the restriction and attractive performance of the uPSAs are clearly depicted. Due to the outstanding performance of the GIA, a hybrid kPSA-GIA is proposed to boost the performance of a kPSA and relieve the fringe density restriction of the GIA.
Systematic error analysis and parameter design of a vision-based phase estimation method for ultra-precision positioning
Authors: Cheng Qinrui , Xu Ting , Huang Peisen
Published: February 2022

Ultra-precision position measurement is increasingly important in advanced manufacturing such as the semiconductor industry and fiber optics or photonics. A vision-based phase estimation method we proposed previously performs position measurement by imaging a 2D periodic pattern. In this paper, systematic errors of this method are analyzed and derived mathematically, which are classified into two types: spectrum leakage error caused by image truncation and window function modulation, and sub-pixel error resulting from discrete Fourier transform (DFT) intensity interpolation. Key design parameters are concluded including pattern period T, camera pixel size t and resolution N, as well as the type of window function used. Numerical simulations are conducted to investigate the relationship between the phase errors and design parameters. Then an error reduction method is proposed. Finally, the improved performance of parameter optimization is validated by a comparative experiment. Experimental results show the measurement errors of the prototype are within ∼2 nm in X or Y axis, and ∼1 µrad in axis, which reaches the sub-pixel accuracy better than 10−3pixel.
Roll angle autocollimator measurement method based on a cylindrical cube-corner reflector with a high resolution and large range
Authors: Li Renpu , Xie Linyi , Zhen Yan , Xiao Han , Wang Wei , Guo Junqi , Konyakhin Igor , Nikitin Mikhail , Yu Xiaolong
Published: February 2022

A novel high-resolution and large-range autocollimator measurement system for roll angle is proposed. The system retains the basic internal structure of the traditional autocollimator (AC), which only uses a novel non-standard cylindrical cube-corner reflector (CCCR) instead of the planar reflector. In the article, the mathematical relationship between the structure of this special reflector and the spatial coordinate vector change of the reflected beam is deduced, and the measurement formula of the roll angle autocollimator (RAC) measurement system is established based on this mathematical relationship. The effectiveness of the measurement system and method is verified by experiments. Experimental results show that this method can effectively enhance the range to ±20°, and the whole measurement accuracy is 6.1”, the measuring resolution is 1”.
Realization of inversely designed metagrating for highly efficient large angle beam deflection
Authors: Ye Taikang , Wu Dan , Wu Qinfei , Sun Xiao Wei , Liang Haowen , Wang Kai , Hong Minghui
Published: February 2022

Directional emission source is one of the key components for multiple-view three-dimensional display. It is hard to achieve high efficiency and large deflection angle direction sources via geometric optics due to the weak confinement of light. The metasurface especially metagrating provides a promising method to control light effectively. However, the conventional forward design methods for metasurface are inherently limited by insufficient control of Bloch modes, which causes a significant efficiency drop at a large deflection angle. Here, we obtained high efficiency large deflection angle metagratings by realizing the constructive interferences among the propagation Bloch modes and enhancing the outcoupling effect at the desired diffraction order. The grating structures that support the coupling of Bloch modes were designed by an inverse design method for different incident wavelengths, and the total phase response of a supercell can be tailored. For a red (620 nm) incident light, the theoretical deflection efficiency of a silicon metagrating can be higher than 80% from 30° to 80°. The experimental deflection efficiency can achieve 86.43% for a 75° deflection metagrating. The matched simulation and experimental results strongly support the reliability of developed algorithm. Our inverse design approach could be extended to the green (530 nm) and blue (460 nm) incident light with titanium dioxide metagratings, with theoretical deflection efficiency of over 80% in a large deflection angle range of 30° to 80°. Considering the multiple visible wavelength deflection capability, the developed algorithm can be potentially applied for full color three-dimensional display, and other functional metagrating devices based on different dielectric materials.