bluuebunny/crossref_metadata_2025 huggingface dataset:
Loss of Prm1 leads to defective chromatin protamination, impaired PRM2 processing, reduced sperm motility and subfertility in male mice
Authors: Merges Gina Esther , Meier Julia , Schneider Simon , Kruse Alexander , Fröbius Andreas Christian , Kirfel Gregor , Steger Klaus , Arévalo Lena , Schorle Hubert
Published: May 2022

One of the key events during spermiogenesis is the hypercondensation of chromatin by substitution of the majority of histones by protamines. In humans and mice, protamine 1 (PRM1/Prm1) and protamine 2 (PRM2/Prm2) are expressed in a species-specific ratio. Using CRISPR-Cas9-mediated gene editing, we generated Prm1-deficient mice and demonstrated that Prm1+/− mice were subfertile, whereas Prm1−/− mice were infertile. Prm1−/− and Prm2−/− sperm showed high levels of reactive oxygen species-mediated DNA damage and increased histone retention. In contrast, Prm1+/− sperm displayed only moderate DNA damage. The majority of Prm1+/− sperm were CMA3 positive, indicating protamine-deficient chromatin, although this was not the result of increased histone retention in Prm1+/− sperm. However, sperm from Prm1+/− and Prm1−/− mice contained high levels of incompletely processed PRM2. Furthermore, the PRM1:PRM2 ratio was skewed from 1:2 in wild type to 1:5 in Prm1+/− animals. Our results reveal that PRM1 is required for proper PRM2 processing to produce mature PRM2, which, together with PRM1, is able to hypercondense DNA. Thus, the species-specific PRM1:PRM2 ratio has to be precisely controlled in order to retain full fertility.
Gendered Impacts of COVID-19 in Developing Countries
Authors: Alon Titan , Doepke Matthias , Manysheva Kristina , Tertilt Michèle
Published: May 2022

In many high-income economies, the COVID-19 recession has resulted in unprecedented declines in women's employment. We examine how the forces that underlie this observation play out in developing countries. A force affecting high- and low-income countries alike is increased childcare needs during school closures. In Nigeria, mothers of school-age children experience the largest declines in employment during the pandemic, just as in high-income countries. A key difference is the role of the sectoral distribution of employment: whereas in high-income economies, reduced employment in contact-intensive services had a large impact on women, this sector plays a minor role in low-income countries.
What’s in a Job? Evaluating the Effect of Private Sector Employment Experience on Student Academic Outcomes
Authors: Modestino Alicia Sasser , Paul Urbashee , McLaughlin Joseph
Published: May 2022

Although subsidized summer jobs programs have been shown to improve youth outcomes, little is known about the effects of private sector employment experiences. We study a unique program that brokers employer-paid summer internships for youth across a variety of industries and occupations. Using administrative data, we employ fixed effects and matching models to estimate the impact of these internships on academic outcomes. We find that private sector job experience significantly increases attendance, reduces course failures, and raises proficiency on statewide exams. Participants are more likely to take the SAT and enroll in college with a shift from two-year to four-year institutions.
How Early Adolescent Skills and Preferences Shape Economics Education Choices
Authors: Fiala Lenka , Humphries John Eric , Joensen Juanna Schrøter , Karna Uditi , List John A. , Veramendi Gregory F.
Published: May 2022

Leveraging data from Sweden and Chicago, we study the educational pipeline for science, technology, engineering, and mathematics (STEM) and economics majors to better understand the determinants of the gender gap and when these determinants arise. We present three findings. First, females are less likely to select STEM courses in high school despite equal or better preparation. Second, there are important gender differences in preferences and beliefs, even conditional on ability. Third, early differences in preferences and beliefs explain more of the gaps in high school sorting than other candidate variables. High school sorting then explains a large portion of the gender difference in college majors.
Saving Effects of a Real-Life Imperfectly Implemented Wealth Tax: Evidence from Norwegian Micro Data
Authors: Alstadsæter Annette , Bjørneby Marie , Kopczuk Wojciech , Markussen Simen , Røed Knut
Published: May 2022

Countries that implement wealth taxes make many practical compromises regarding relative treatment and approach to valuation of different categories of assets in order to ease assessment and liquidity difficulties with this form of taxation. Relying on Norwegian variation in tax and base rules, we illustrate the resulting complexity and evaluate the effect of taxation on saving and portfolio composition. Our results highlight the sensitivity of the strength of response to the base definition.
Artificial Intelligence, Algorithm Design, and Pricing
Authors: Asker John , Fershtman Chaim , Pakes Ariel
Published: May 2022

We calculate the time path of prices generated by algorithmic pricing games that differ in their learning protocols. Asynchronous learning occurs when the algorithm only learns about the return from the action it actually took. Synchronous learning occurs when the artificial intelligence conducts counterfactuals to learn about the returns it would have earned had it taken an alternative action. In a simple market setting, we show that synchronous updating can lead to competitive pricing, while asynchronous updating can lead to pricing close to monopoly levels. However, building simple economic reasoning into the asynchronous algorithms significantly modifies the prices it generates.
Inference for Losers
Authors: Andrews Isaiah , Bowen Dillon , Kitagawa Toru , McCloskey Adam
Published: May 2022

Researchers frequently report league tables ranking units (neighborhoods or firms, for instance) based on estimated coefficients. Since the rankings are formed based on estimates, however, the coefficients reported in league tables suffer from selection bias, with estimates for highly ranked units biased upward and those for low-ranked units biased downward. Further, conventional confidence intervals can undercover. This paper introduces corrected estimators and confidence intervals that address these biases, ensuring that estimates and confidence intervals reported for each position in a league table are median unbiased and have correct coverage, respectively.
Poor Performance as a Predictable Outcome: Financing the Administration of Unemployment Insurance
Authors: Lachowska Marta , Mas Alexandre , Woodbury Stephen A.
Published: May 2022

Effective administration of unemployment insurance (UI) is central to its ability to smooth consumption and act as an automatic stabilizer. The federal government's method of allocating funds to administer UI gives the states no incentive to provide quality service at reasonable cost. We first document the deteriorating performance of the UI system in recent recessions and present estimates of a descriptive model relating state workloads to performance. We then characterize UI administration as a standard principal-agent problem, which leads to a method of allocating funds that would motivate states to adopt new technologies and improve performance.
Would Broadening the UI Tax Base Help Low-Income Workers?
Authors: Duggan Mark , Guo Audrey , Johnston Andrew C.
Published: May 2022

Unemployment insurance (UI) tax bases vary significantly in the United States, from a low of $7,000 annually in California to a high of $52,700 in Washington. Previous research has provided surprisingly little guidance regarding the consequences of this variation for either workers or employers. We use 37 years of data for all 50 states and Washington, DC, to estimate the impact of the UI tax base on part-time work. We find that the low tax base that exists in many states (and the necessarily higher tax rates that accompany them) lowers labor demand for part-time and other low-earning workers.
Weak Corporate Insolvency Rules: The Missing Driver of Zombie Lending
Authors: Becker Bo , Ivashina Victoria
Published: May 2022

“Zombie lending”--lending to less-productive firms at subsidized rates--can help banks with misaligned incentives in the short run, but it prolongs economic downturns. We propose that inefficient resolution of insolvency is a significant contributor to this problem. We exploit variation in the efficiency of insolvency across countries to show that lack of formal bankruptcies, cheap (zombie) credit, and stickiness of existing creditors is more common in bad economic periods when insolvency works less well.
Addressing Strategic Uncertainty with Incentives and Information
Authors: Halac Marina , Lipnowski Elliot , Rappoport Daniel
Published: May 2022

A principal privately contracts with a set of agents who then simultaneously make a binary decision. Each contract specifies an individual allocation and the information the agent is given about a fundamental state and other agents' contracts. We study the principal's optimal scheme that induces a desired action profile as the unique rationalizable outcome. Our main result reduces this multiagent problem to a two-step procedure where information is designed agent-by-agent: the principal chooses a fundamental-state-contingent distribution over agent rankings and, separately for each agent, the agent's information about the realized ranking and fundamental states. We illustrate with a team-production application.
Police Frisks
Authors: Abrams David S. , Fang Hanming , Goonetilleke Priyanka
Published: May 2022

The standard economic model of police frisks implies that the contraband hit rate should rise when the number of frisks falls, ceteris paribus. We provide the first empirical corroboration of such models of police behavior by examining changes in frisks following the killing of George Floyd in 2020. We find that hit rates from pedestrian frisks rose as police frisks fell dramatically. Using detailed data, we rule out several alternative explanations, including changes in street population, crime, and police allocation. Our findings provide quantitative estimates that can contribute to the important goals of improving and reforming policing.
Measuring Police Performance: Public Attitudes Expressed in Twitter
Authors: Kim Taeho
Published: May 2022

I study the viability of Twitter-based measures for measuring public attitudes about the police. I find that Twitter-based measures track Gallup's measure of public attitudes toward the police starting around 2014, when the Twitter user base stabilized, but not before 2014. Increases in Black Lives Matter protests are also associated with increases in negative sentiment measures from Twitter. The findings suggest that Twitter-based measures can be used to acquire granular evaluations of police performance, but they are more useful in analyzing panel data of multiple agencies over time rather than in tracking a single geographical area over time.
More than Shelter: The Effect of Rental Eviction Moratoria on Household Well-Being
Authors: An Xudong , Gabriel Stuart A. , Tzur-Ilan Nitzan
Published: May 2022

We investigate the impact of the 2020 COVID-19 rental eviction moratoria on household well-being. Analysis of new panel data indicates that eviction moratoria reduced evictions and resulted in redirection of scarce household financial resources to immediate consumption needs, notably including food and grocery spending. We also find that eviction moratoria reduced household food insecurity and mental stress, with larger effects evidenced among African American households. Findings suggest broad salutary effects of eviction moratoria during a period of widespread virus and economic distress.
Measuring Changes in Disparity Gaps: An Application to Health Insurance
Authors: Goldsmith-Pinkham Paul , Jiang Karen , Song Zirui , Wallace Jacob
Published: May 2022

We propose a method for reporting how program evaluations reduce gaps between groups, such as the gender or Black-White gap. We first show that the reduction in disparities between groups can be written as the difference in conditional average treatment effects (CATE) for each group. Then, using a Kitagawa-Oaxaca-Blinder-style decomposition, we highlight how these CATE can be decomposed into unexplained differences in CATE in other observables versus differences in composition across other observables (e.g. the “endowment”). Finally, we apply this approach to study the impact of Medicare on American's access to health insurance.
Gender Disparities in Career Advancement across the Transition to Parenthood: Evidence from the Marine Corps
Authors: Healy Olivia J. , Heissel Jennifer A.
Published: May 2022

We isolate the effect of childbirth on mothers' and fathers' job-relevant physical performance using data from the US Marines. We estimate event study models around the first birth. We assign “placebo births” to non-parents using LASSO-selected predictors of parenthood to estimate counterfactual trends. We find large and persistent effects of motherhood on performance. Two years postbirth, mothers' physical performance remains 0.2 standard deviations lower than non-mothers'. For fathers, the birth also initially lowers performance, but fathers are able to recover. This research demonstrates a potential mechanism behind the child penalty to mothers' earnings.
Productivity of mother pigs is lower in countries that still confine them in gestation crates
Authors: Schuck-Paim Cynthia , Alonso Wladimir J.
Published: May 2022

Background: For decades, pig farmers have used gestation crates — small metal enclosures about two feet wide — to confine pregnant sows (female breeding pigs). Gestation crates physically restrain sows for most of their life, preventing them from walking or even turning around. Millions of females are still housed in these systems. Growing societal concern about animal welfare has been pressuring the industry for change, with recent legislation in the European Union and California restricting the use of crates. Still, the notion that gestation crates negatively affect sow welfare has been challenged by producers in regions where crates are widely used, who argue that, by facilitating health monitoring and preventing aggression, crates lead to lower sow mortality and higher piglet outputs per sow. We address these claims by comparing sow mortality and performance across countries with different housing systems.

Methods: To this end, we use publicly available data from InterPig, a network of pig production economists in 17 countries that provides internationally harmonized methods for meaningful comparisons of national production data.

Results: The results show that sow mortality is significantly higher, and annual pig production per sow significantly lower, in those countries where gestation crates are still the norm compared to countries in the European Union, where use of gestation crates is restricted to up to four weeks after insemination.

Conclusions: Claims of higher mortality and reduced productivity per sow in crate-free systems are not substantiated by this data. This evidence should be considered in policies affecting the welfare of breeding pigs.
Quantitative image analysis in COVID-19 acute respiratory distress syndrome: a cohort observational study.
Authors: Dolinay Tamas , Jun Dale , Maller Abigail , Chung Augustine , Grimes Brandon , Hsu Lillian , Nelson David , Villagas Bianca , Kim Grace Hyun J , Goldin Jonathan
Published: May 2022

Background

Acute respiratory distress syndrome (ARDS) is a severe form of acute lung injury commonly associated with pneumonia, including coronavirus disease-19 (COVID-19). The resultant effect can be persistent lung damage, but its extent is not known. We used quantitative high resolution computed tomography (QHR-CT) lung scans to radiographically characterize the lung damage in COVID-19 ARDS (CARDS) survivors.

Methods

Patients with CARDS (N=20) underwent QHR-CT lung scans 60 to 90 days after initial diagnosis, while hospitalized at a long-term acute care hospital (LTACH). QHR-CT assessed for mixed disease (QMD), ground glass opacities (QGGO), consolidation (QCON) and normal lung tissue (QNL). QMD was correlated with respiratory support on admission, tracheostomy decannulation and supplementary oxygen need on discharge.

Results

Sixteen patients arrived with tracheostomy requiring invasive mechanical ventilation. Four patients arrived on nasal oxygen support. Of the patients included in this study 10 had the tracheostomy cannula removed, four remained on invasive ventilation, and two died. QHR-CT showed 45% QMD, 28.1% QGGO, 3.0% QCON and QNL=23.9%. Patients with mandatory mechanical ventilation had the highest proportion of QMD when compared to no mechanical ventilation. There was no correlation between QMD and tracheostomy decannulation or need for supplementary oxygen at discharge.

Conclusions

Our data shows severe ongoing lung injury in patients with CARDS, beyond what is usually expected in ARDS. In this severely ill population, the extent of mixed disease correlates with mechanical ventilation, signaling formation of interstitial lung disease. QHR-CT analysis can be useful in the post-acute setting to evaluate for interstitial changes in ARDS.
Literary English
Authors: Man'kovskaya Zoya
Published: May 2022

The textbook is intended for the development of lexical, translation and communicative competencies of students of the humanities. It introduces students to the use of literary English in classical and modern works of fiction, films, radio and television programs, theatrical productions, in the genre of public speaking, interviews and news, contributing to the expansion of their linguistic horizons, increasing their creative potential and independence of thinking in English.
The student expands his vocabulary, acquires skills: understanding and correct interpretation of the studied vocabulary in various contexts; expressing his own point of view; translation.
Meets the requirements of the federal state educational standards of higher education of the new generation.
For students of the first and second courses of the "Linguistics" direction, as well as for the faculties of foreign languages and journalism.
Business communication and cross-cultural communication
Authors: Zhukova Evgeniya , Suvorova Tat'yana
Published: May 2022

The textbook includes three sections, consistently revealing the topics "Cross-cultural communication as the interaction of different cultures", "Business communication as the basis of cross-cultural communications", "Ethical standards in professional activity". The textbook discusses the specifics of the implementation of cross-cultural business communications, taking into account modern changes in communication methods. At the end of each section there are questions and tasks for self-examination, tests, additional literature for a more complete study of the problems of business cross-cultural communications.
Meets the requirements of the federal state educational standards of higher education of the latest generation.
For undergraduate students studying in the areas of "Economics", "Management", "Personnel Management", "State and Municipal Management", "Business Informatics", "Trade", "Commodity Science", "Housing and communal infrastructure", as well as for anyone interested in business problems cross-cultural communications.
Risk management in construction
Authors: Astaf'eva Ol'ga , Moiseenko Natal'ya , Kozlovskiy Aleksandr , Shemyakina Tat'yana , Serov Viktor
Published: May 2022

The monograph is devoted to the issues of risk management in the organizations of the investment and construction complex. The issues of risk classification are consistently considered, approaches to determining the types and types of risks are established. Attention is paid to approaches to the construction of a risk management mechanism and the specifics of the impact on the identified risks in terms of minimizing possible damage. The issues of state regulation are highlighted, a complex economic problem related to the study of the effectiveness of the chosen strategy of real investment projects based on the use of various methods and models of risk analysis is considered. Modern educational and methodological materials tested in the practice of enterprises and organizations of the construction complex of Moscow and the Moscow region were used.
For a wide range of readers interested in the issues of risk management in construction. It will be useful for students, postgraduates and teachers of economic universities.
Sources and forms of modern Russian law
Authors: Chashin Aleksandr
Published: May 2022

The monograph reveals the concept, role and functions of the form of law in the modern Russian legal system. The author turns to the ontological foundations of knowledge of the sources of law. Attention is focused on the legal doctrine and its application as a form of law in modern legal proceedings both in Russia and in a number of neighboring countries. At the same time, judicial acts of a number of foreign states are being introduced into scientific circulation. The theoretical substantiation of the possibility of distinguishing the hypostases of the legal doctrine, considered as a condition for the formation of an open civil society, is given. The primacy of legal doctrine over judicial precedent and legal custom is proved against the background of its subsidiary effect in relation to a normative legal act. A significant part is devoted to the problems of modern codification activities and the prospects for creating a Code of laws of the Russian Federation.
For a wide range of readers interested in legal issues. It can be useful for students, postgraduates and teachers of law schools.
Improving the characteristics of electrical insulation materials of windings of electric machines
Authors: Burkov Aleksey , Nikolaev Dmitriy , Yurin Valeriy
Published: May 2022

The monograph presents the issues of theory, considers methods and means of improving the quality characteristics of insulation of electrical machines, presents the results of the development of effective scientific and technical solutions aimed at improving the quality of technical characteristics of electrical insulation of marine electrical machines, based on theoretical research and generalized analysis of monitoring of operational tests of marine electrical equipment, modernization of technical implementations, experimental studies and comparative assessments.
For specialists in the field of electrical engineering, in particular marine electrical equipment. It can be used by graduate students, cadets and students in the special education system.
Project management
Authors: Antonov Gennadiy , Ivanova Ol'ga , Tumin Valeriy , Daneykin Yuriy , Kostromin Petr
Published: May 2022

The textbook discusses theoretical, methodological and practical issues of project management. The understanding of the place of project activity in the organization, the current state of project management, project classification, processes and methods of project timing, cost, risk management, evaluation of investment attractiveness of projects, portfolio management and project programs in the organization is presented.
Meets the requirements of the federal state educational standards of higher education of the latest generation.
For undergraduate students studying in the areas of "Economics", "Management", "Innovation", "State and Municipal Administration", "Housing and communal infrastructure", as well as in engineering, technological and other areas and specialties providing for the study of disciplines of economic, organizational and management cycles. It can be used by students studying in master's and postgraduate studies, students of business schools and advanced training and retraining courses, university teachers, employees of research and consulting firms, business structures, managers and specialists of organizations.
Economic and energy diplomacy in the context of the fourth energy transition
Authors: Seregina Antonina
Published: May 2022

This textbook is intended to contribute to a lot of work on finding the optimal scenario for adapting the Russian economy to the global energy transition. The textbook reveals the features of the fourth energy transition, the purpose of which is to replace fossil fuels with renewable energy sources.
It is intended for undergraduate and graduate students studying in educational institutions of higher education in the implementation of the main professional educational programs in the areas of training "International Relations" and "Economics".
Constitutional and legal support of the national security of the Russian Federation
Authors: Fedotova Yuliya
Published: May 2022

The textbook is devoted to the constitutional and legal basis (the concept, historical features of the formation and development of the constitutional system of Russia, its political, socio-economic and spiritual foundations, the concept, essence, content and purpose of constitutional security as a legal expression of national security) and the system of ensuring national security of the Russian Federation, expressed in the state (consisting of the activities of state bodies government and other state bodies to ensure national security) and non-state (characterized by the participation of citizens and their associations and other organizations in ensuring national security) its subsystems.
Meets the requirements of the federal state educational standards of higher education of the latest generation.
For students, postgraduates, teachers, specialists in the field of constitutional law and national security law, practitioners, as well as for a wide range of readers interested in the problems of ensuring national security.
Countering crimes committed in the sphere of cryptocurrency turnover
Authors: Andreev Aleksey , Galiev Denis , Gonchar Vladimir , Gorach Nikolay , Zhilkin Maksim , Kachalov Vladislav , Lyuban Vladislav , Mihaylenko Natal'ya , Molchanova Tat'yana , Russkevich Evgeniy , Himicheva Ol'ga
Published: May 2022

The textbook is devoted to a complex of theoretical and applied problems of countering crimes committed using cryptocurrencies. Along with the theoretical issues of the legal status of cryptocurrencies and the general criminological characteristics, applied problems of qualification of relevant crimes, issues of their investigation, operational investigative activities, as well as the organization of official activities are subjected to in-depth analysis. Based on the conducted research, the paper presents relevant conclusions and recommendations.
Meets the requirements of the federal state educational standards of the latest generation in the enlarged groups of specialties "Jurisprudence".
It is recommended first of all to students of master's degree programs, training programs for scientific and pedagogical personnel and additional professional education, as well as scientific and pedagogical workers. It can also be used by students of other higher education programs (bachelor's degree, specialty), practical staff and anyone interested in the relevant issues.
Predictors of quality of life in women with postmenopausal osteoporosis
Authors: Górczewska Bogumiła , Jakubowska-Pietkiewicz Elżbieta
Published: May 2022

Cel pracy

Celem badania była ocena jakości życia w skali QUALEFFO-41, u kobiet z osteoporozą pomenopauzalną w zależności od czynników socioepidemiologicznych.

Metoda

Osteoporoza jest chorobą społeczną i epidemią XXI wieku. W starzejącym sie polskim społeczeństwie choroba ta jest coraz większym problemem. Badanie miało na celu ocenę predyktorów jakości życia u kobiet z osteoporozą pomenopauzalną.

Badanie miało charakter ambulatoryjny, ankietowy, przeprowadzono je w okresie od VI.2018 do V.2019 roku. Objęto grupę 198 kobiet w wieku 72,31±8,59 lat z rozpoznaną osteoporozą pomenopauzalną w dwóch Poradniach Leczenia Osteoporozy na terenie miasta Łodzi (Polska). Kryterium doboru ankietowanych była rozpoznana osteoporoza pomenopauzalna w historii pacjentek według ICD 10 - M81.0 oraz brak istotnych schorzeń przewlekłych wymagających systematycznego leczenia.

W pracy wykorzystano: polską wersję skali jakości życia QUALEFFO-41, skalę VAS oraz ankietę własnego autorstwa. Dane analizowano przy użyciu wielokrotnej regresji liniowej. Analizę statystyczną wykonano w programie Statistica 13.0.

Wyniki

Średni wynik QUALEFFO-41 wyniósł 40,26±16,92 pkt. Analizując poszczególne domeny QUALEFFO-41 najniższą jakość życia stwierdzono w domenie funkcji umysłowych 48,49±18,06 pkt. Domena czynności fizyczne w ciągu dnia była dwukrotnie lepiej oceniona w porównaniu do domeny funkcje psychiczne.

Stan cywilny, wykształcenie i sytuacja materialna miały istotny statystycznie wpływ na jakość życia (p<0,05). Wykazano, że ból wyrażany w skali VAS, ból wybudzający ze snu, zażywanie środków nasennych oraz starszy wiek badanych pogarsza ich jakość życia.

Wnioski

Kobiety z osteoporozą pomenopauzalną miały przeciętną jakość życia. W Polsce ocena jakości życia pacjentów chorych przewlekle oraz rutynowa ocena poziomu nasilenia dolegliwości bólowych w skali VAS nie jest powszechna.
Spatio-Statistical Analysis of Temperature and Trend Detection in Baluchistan, Pakistan
Authors: Rafiq Muhammad , Li Yue Cong , Cheng Yanpei , Rahman Ghani , Ali Ahmad , Iqbal Muhammad , Latif Ammara , Ali Imtiaz , Rehan Aqsa , Zahoor Aun , Ullah Rahat
Published: May 2022

The assessment of temperature variability in any region of the world is important for prior planning in the context of current climate change. The mean monthly, seasonal and annual temperature data of nine meteorological stations was analysed in this study to determine the temperature variability and trend in Baluchistan province, Pakistan. The non-parametric Mann–Kendall and Sen’s slope estimator were applied to investigate the temperature trend pattern in the study Temperature data from the relevant meteorological stations (met-stations) were collected for this purpose from the Pakistan Meteorological Department and the National Center for Environmental Information. The result revealed an increasing significant trend (IST) in the mean annual temperature at Dalbandin, Kalat, Quetta, Zhob and Gawadar meteorological stations. While the seasonal minimum, maximum and mean temperature showed trend fluctuations in winter, spring and autumn seasons. In the seasonal analysis, the increasing trend has been detected in most of the meteorological stations (Dalbandin, Kalat, Quetta, Zhob, Khuzdar, Lasbella, Gawadar) in all four seasons. Whereas in Sibi met-station, a decreasing significant trend (DST) was recorded in summer (minimum, maximum and mean) and the met-station Barkhan recorded decreasing trend in maximum temperature in the autumn season. The Baluchistan province is totally spread over an arid and semiarid area of Pakistan where temperature fluctuations further aggravate the deprived agriculture and sparse natural vegetation.
Estágios da doença renal crônica e suas associações com o nível de atividade física, qualidade de vida e perfil nutricional
Authors: Caetano Antonio Filipe Pereira , Alves Flavianne Araújo Neves , França Katianne Monique da Silva , Gomes André Victor Ferreira , Silva Juliana Célia de Farias
Published: May 2022

Estudos apresentaram resultados benéficos da prática de exercício físico no tratamento adjuvante à doença renal crônica (DRC). O objetivo desse estudo foi comparar e associar os estágios da evolução da DRC dos pacientes em tratamento conservador com o nível de atividade física, qualidade de vida e o perfil nutricional. A amostra foi composta por pacientes de ambos os sexos, com idade superior aos 18 anos em tratamento conservador para DRC. Foram avaliados o perfil nutricional (índice de massa corporal, circunferência de cintura e percentual de gordura); nível de atividade física (IPAQ); nível de qualidade de vida (WHOQOL-Bref). Participaram do estudo 52 pacientes com idade média de 60,30 ± 9,10 anos, 53,8% mulheres, 57,6% diabéticos e 76,9% hipertensos. Para o perfil nutricional e nível de atividade física, 38,4% eram pessoas com obesidade; 82,6% com valores elevados de circunferência da cintura (CC); e 67% apresentaram baixos níveis baixos de atividade física. Para o nível de qualidade de vida, menores escores em satisfação com saúde (2,98 ± 0,83) e meio ambiente (2,75 ± 0,38); melhores escores em domínio psicológico (3,80 ± 0,53) e relações sociais (3,58 ± 0,58). Não houve associação significativa entre as variáveis do estudo e a estratificação dos pacientes em níveis de filtração glomerular. A correlação foi positiva do estágio DRC somente com a dimensão de relações sociais (rho = 0,247, p = 0,07) do nível de qualidade de vida. Os sujeitos apresentaram baixos níveis de atividade física e elevado prevalência de excesso de peso/obesidade, mas estes níveis não se alteraram em associação com os estágios da DRC.
Musculoskeletal tuberculosis in Bradford
Authors: Craig Andrew D. , Asmar Samir , Whitaker Paul , Shaw David L. , Saralaya Dinesh
Published: May 2022

Aims

Tuberculosis (TB) is one of the biggest communicable causes of mortality worldwide. While incidence in the UK has continued to fall since 2011, Bradford retains one of the highest TB rates in the UK. This study aims to examine the local disease burden of musculoskeletal (MSK) TB, by analyzing common presenting factors within the famously diverse population of Bradford.

Methods

An observational study was conducted, using data from the Bradford Teaching Hospitals TB database of patients with a formal diagnosis of MSK TB between January 2005 and July 2017. Patient data included demographic data (including nationality/date of entry to the UK), disease focus, microbiology, and management strategies. Disease incidence was calculated using population data from the Office for National Statistics. Poisson confidence intervals were calculated to demonstrate the extent of statistical error. Disease incidence and nationality were also analyzed, and correlation sought, using the chi-squared test.

Results

Between January 2005 and July 2017, 109 cases of MSK TB were diagnosed in Bradford. Mean incidence was 1.65 per 100,000 population, per calendar year (SD 0.75). A total of 38 cases required surgical intervention. Low rates of antimicrobial resistance were encountered. A low rate of loss to follow-up was observed (four patients; 3.7%). Overall, 94.5% of patients (n = 103) were successfully treated. 67% of patients (n = 73) reported their country of origin as either India, Pakistan, or Bangladesh. These ethnicities account for around 25% of the local population.

Conclusion

Bradford maintains a high prevalence of MSK TB infection relative to national data; the prevalence within the local immigrant population remains grossly disproportionate. Typical associated factors (HIV/hepatitis coinfection, drug resistance), have only modest prevalence in our dataset. However, local socioeconomic factors such as deprivation and poverty appear germane as suggested by global literature. We advocate a high degree of suspicion in treatment of atypical infection in any area with similar population factors to ensure timely diagnosis. Cite this article: Bone Jt Open 2022;3(5):432–440.
In-motion continuous point cloud measurement based on bundle adjustment fused with motion information of triple line-scan images
Authors: Liao Ruiying , Yang Linghui , Ma Luyao , Zhu Jigui
Published: May 2022

The point cloud continuous measurements in some in-motion circumstances, such as quality inspection of products on assembly lines or rail traffic, have been requiring higher measurement speed, accuracy, and point cloud density. With the advantages of high acquisition rates and ultrahigh resolution, line-scan cameras have been developing gradually for dynamic measurements. However, because of non-coplanar installation and unidimensional images, the measurement based on line-scan cameras is affected by movement. In this article, a dynamic scanning point cloud measurement based on triple line-scan images is present. The point cloud optimization is based on bundle adjustment fused with motion information. The epipolar constraint of line-scan images in dynamic conditions is researched for matching. The effect of motion on matching error is analyzed. A triple line-scan cameras experimental setup validates the proposed method.
Influence of thermal stress on continuous-wave second-harmonic generation in periodically poled LiTaO3 crystals
Authors: Kato Susumu , Kurimura Sunao , Mio Norikatsu
Published: May 2022

Thermal stress effects on continuous-wave second-harmonic generation in periodically poled LiTaO3 crystals are evaluated via a numerical simulation that is based on nonlinear propagation equations and a thermal conduction equation. The thermal performance and absorption coefficients used in the numerical simulation were determined by comparison with experimental results. The results show that the thermal stress caused by a small residual absorption would restrict the maximum output power of a second-harmonic-continuous-wave laser.
Impact of feedback bandwidth on Raman random fiber laser remote-sensing
Authors: Qi Yifei , Lin Shengtao , Zhang Jiaojiao , Wang Pan , Wang Zinan
Published: May 2022

In the ultra-long distance sensing domain, recently Raman random fiber laser (RRFL) demonstrated advantages of ultrawide sensing-bandwidth in dynamic sensing, compared with pulse-probing cases. However, such a scheme is still in the preliminary stage, and the key parameters such as sensitivity have not been characterized. In this work, a time-dependent spectrum-balanced model is proposed, which can accurately and quickly describe the spectral shape of RRFL and the evolution of the power and the spectrum. Based on this model, the relationship between the sensitivity and the feedback bandwidth is studied. The calculated results show that the sensitivity is inversely proportional to the feedback bandwidth. Then in the proof-of-concept experiment, by changing the bandwidth of sensing FBG, the results of sensitivity are well coincident with the simulation. This work provides an effective platform for studying the evolution of RRFL spectrum, as well as a novel way for further enhancing the performance of the dynamic sensing system based on ultra-long RRFL.
2D rigorous coupled wave analysis with adaptive spatial resolution for a multilayer periodic structure
Authors: Wang Lin , Fang Debao , Jin Haibo , Li Jingbo
Published: May 2022

We utilize the 2D modal solution of rigorous coupled wave analysis with adaptive spatial resolution to enhance the reliability of standard RCWA for multilayer gratings with metal-dielectric structures. The conversion relation in modal solutions between the Cartesian system and the transformed system is for the first time established. Based on the proposed conversion relation, the modal solution of the metal-dielectric structure obtained in the transformed system can match the boundary conditions with modal solutions of other different grating layers in the Cartesian system. Numerical results show that even for metal patches in microwave band, the above method can still achieve good convergence and is perfectly suitable for multi-layer structure calculation.
Pulse temporal scaling of LIDT for anti-reflective coatings deposited on lithium triborate crystals
Authors: Atkočaitis Erikas , Smalakys Linas , Melninkaitis Andrius
Published: May 2022

Anti-reflective (AR) coatings minimize photon losses of optics when it comes to the transmission of light, thus, are broadly used for imaging and laser applications. However, the maximum output power in high-power lasers is limited by the so-called laser-induced damage threshold (LIDT) parameter of optical elements. Often AR coated nonlinear crystals are responsible for such limitations, however, LIDT data is rather scarce. Thus, only limited understanding about LIDT pulse temporal scaling laws for AR coatings exists, which also lacks the specificity about fatigue effect of distinct failure modes. To expand the present knowledge four identical lithium triborate (LBO) crystals were prepared. Each crystal had one side coated with the AR@1064+532 nm coating and the opposite side coated with the AR@355 nm coating. Multiple LIDT tests were then conducted following 1-on-1 and S-on-1 testing protocols at UV and IR wavelengths while varying laser pulse duration. Empirical scaling laws are then investigated for different failure modes and later interpreted using a numerical model.
Portable autostereoscopic display based on multi-directional backlight
Authors: Li Ziyin , Gao Chen , Li Haifeng , Wu Rengmao , Liu Xu
Published: May 2022

A multi-directional backlight autostereoscopic display system with high resolution, low crosstalk, and motion parallax is developed in this paper. The proposed multi-directional backlight system is based on the Bragg mismatched reconstruction of volume holographic optical element (VHOE), and includes a set of light sources which are uniformly arrayed along one direction. Each light source produces its corresponding directional lighting to follow the human eye position detected by an eye tracker. Two scenarios are presented to build the multi-directional backlight system. The prism-type backlight system which guides the incident beam with a prism is relatively simple and easy to implement. The waveguide-type one which employs a transflective film to expand the incident light beam within the waveguide and modulate the intensity of the incident beam, is relatively thin and is applicable to large-area display. Two prototypes are built and the effectiveness of the proposed autostereoscopic display system is verified by the experimental results.
Thermal-birefringence-induced depolarization in a 450 W Ho:YAG MOPA system
Authors: Mi Shuyi , Tang Jinwen , Wei Disheng , Yao Baoquan , Li Junhui , Yang Ke , Dai Tongyu , Duan Xiaoming
Published: May 2022

We demonstrated an efficient, high-power Ho:YAG master-oscillator power amplifier (MOPA) system and investigated its thermal-birefringence-induced depolarization. The maximum output power was 450 W with a depolarized power of 32.1 W and depolarization of 0.071 via three power amplifiers. To our knowledge, this is the highest average power generated from a Ho:YAG MOPA system. In theory, a simplified model was built to calculate the depolarization in the amplifier, and the theoretical results agreed with the actual value well. Moreover, the overall optical-to-optical efficiency of the MOPA system was near 60%, and the beam quality M2 factors of s-polarized laser were measured to be ∼ 1.8 at 400 W. In pulse operation, the per pulse energy was ∼ 11 mJ at the pulse repetition frequency of 40 kHz with the corresponding peak power of 220 kW.
Pulse chirp enhances the laser acceleration of neutral particles
Authors: Sun R. , Wang W. , Wang P. X.
Published: May 2022

Accelerating neutral atoms is challenging because such particles are not directly manipulated by electric and magnetic fields as charged particles. In our acceleration scheme, the excited atom requires a sufficiently high gradient acceleration force. The key challenge in laser acceleration experiments is that not only must the photon energy excite atoms to the Rydberg state, but also atoms must not be ionized in an intense laser field. In this Letter, we propose using a chirped laser pulse to achieve the objectives above. The enhancement effect of the pulse chirp on the laser acceleration of neutral particles is investigated via numerical simulation and analytical analysis.
Tunable optical frequency comb with hundred-GHz spacings generated on a silicon waveguide
Authors: Zhang Yuanfei , Zhang Honghui , Shu Chester
Published: May 2022

We demonstrate the generation of optical frequency combs with tunable spacing at the hundred-GHz range in the 1550-nm window. The widely spaced combs are realized through silicon-based cross-phase modulation. The optical pump is prepared by multiplication of a 10-GHz train of 1.7-ps pedestal-free pulses. Energy-efficient temporal Talbot processing is used to multiply the repetition rate by a factor of up to 20. In our approach, the multiplication factor can be flexibly controlled by tuning the temporal dispersion inside an optical processor. Optical frequency combs with spacings ranging from 140 to 200 GHz have been successfully generated with a maximum carrier-to-noise suppression ratio of ∼45 dB.
Circular Mathieu and Weber autofocusing beams
Authors: Zhang Yong , Mo Zhenwu , Xu Danling , He Shangling , Ding Yiping , Huang Qiaobing , Lu Zhili , Deng Dongmei
Published: May 2022

In this Letter, the new classes of non-paraxial autofocusing beams are introduced for the first time, to the best of our knowledge. We investigate both numerically and experimentally non-paraxial circular Mathieu and Weber autofocusing beams based on the solutions of the Helmholtz equation in elliptical and parabolic coordinates, respectively. The results show that such beams can significantly shorten the focus distance, and eliminate the intense oscillation effectively after the focusing point. The focal length and the peak intensity can be controlled by tunable parameters. In addition, we further experimentally realize their application of such beams in optical trapping.
Nonlinearity-aware PS-PAM-16 transmission for C-band net-300-Gbit/s/λ short-reach optical interconnects with a single DAC
Authors: Zhang Junwei , Wu Xiong , Yan Qifeng , Tan Heyun , Hong Xiaojian , Fei Chao , Lau Alan Pak Tao , Lu Chao
Published: May 2022

A nonlinearity-aware signal transmission scheme based on a low-complexity 3rd-order diagonally pruned absolute-term nonlinear equalizer (NLE) with weight sharing (DP-AT-NLE-WS) and rate-adaptable probabilistically shaped 16-level pulse amplitude modulation (PS-PAM-16) signal is proposed and experimentally demonstrated for C-band net-300-Gbit/s/λ short-reach optical interconnects. By replacing the multiplication operation with the absolute operation and applying weight sharing to reduce the kernel redundancy, the computational complexity of the proposed 3rd-order DP-AT-NLE-WS is reduced by >40% compared with the 3rd-order DP-Volterra NLE (DP-VNLE), DP-AT-NLE, and DP-VNLE-WS, with the achieved normalized general mutual information (NGMI) above a threshold of 0.857. Employing a commercial 32-GHz Mach–Zehnder modulator (MZM) and a single digital-to-analog converter (DAC), we demonstrate the single-lane transmission of 100-GBaud PS-PAM-16 signal using DP-AT-NLE-WS in the C band at record 370-Gbit/s line rate and 300.4-Gbit/s net rate over 1-km standard single-mode fiber (SSMF), achieving 21.2% (15.5%) capacity improvement over 100 (105)-GBaud PAM-8 transmission. To the best of our knowledge, this is the first net-300-Gbit/s intensity modulation and direct detection (IM/DD) short-reach transmission in the C band using commercially available components.