bluuebunny/crossref_metadata_2025 huggingface dataset:
Perceptions and help‐seeking behaviours among community‐dwelling older people with urinary incontinence: A systematic integrative review
Authors: Yan Fang , Xiao Lily D. , Zhou Keyi , Li Zeen , Tang Siyuan
Published: February 2022

Aim

To synthesize research evidence on perceptions and help‐seeking behaviours in community‐dwelling older people with urinary incontinence based on the Capability‐Opportunity‐Motivation‐Behaviours model.

Background

Urinary incontinence is highly prevalent in community‐dwelling older people, yet only a small proportion seek help from health professionals. Untreated urinary incontinence has a detrimental impact on older people's quality of life and distresses their caregivers.

Design

Systematic integrative review.

Data sources

Ten databases were searched systematically between 9 November 2020 and 17 December 2020 including Medline (PubMed), CINAHL, Ageline, Web of Science, Scopus, ProQuest, Psyclnfo, CNKI, Wanfang and Vip.

Review methods

Quality appraisal was applied to assess the quality of selected articles. Data relevant to the review aim were extracted from included articles for analysis. Convergent qualitative synthesis was used to synthesize findings.

Results

Twenty articles were included and two main themes with six sub‐themes were identified. Theme one described three common perceptions including urinary incontinence as a part of normal ageing, a stigma and a health problem. Each perception had a profound impact on older people's motivation to self‐report the problem to health professionals. Theme two revealed three main help‐seeking approaches comprising self‐help, help from friends and help from health professionals. Of these, self‐help was the dominant approach used to conceal urinary incontinence and contributed to social isolation.

Conclusion

Improving urinary incontinence management in community‐dwelling older people requires the development of their capability and motivation, and increased opportunities to access and gain help from skilled health professionals.

Impact

Findings can facilitate resource development to improve health literacy for the general public pertinent to urinary incontinence and associated stigma. Moreover, findings can inform a user‐friendly reporting and referral system for the problem. In addition, findings can inform education and skill training for health professionals, older people and their caregivers to effectively manage the problem.
The P‐Word: Power aversion and responsibility aversion as explanations for the avoidance of power
Authors: Hull Kathryn E. , Overbeck Jennifer R. , Smillie Luke D. , Howe Piers D. L.
Published: February 2022

Though we typically think that power is desirable, individuals will sometimes avoid power. One explanation for this behavior is some individuals are averse to the responsibility associated with power and will therefore avoid positions of power. However, people may also avoid power because they perceive it as being inherently negative. This is supported by research on lay theories of power, which suggests that those who endorse the coercive lay theory perceive powerful people as manipulative and deceitful. In this paper, we propose a new theory of power aversion that expands upon the coercive lay theory to more thoroughly explain how negative perceptions of power cause some individuals to avoid it. We draw from previous research to identify specific negative traits associated with power. Based on this, we propose that some power‐averse individuals believe that possessing power will turn them into immoral, cold, selfish, and unjust people. For this reason, they avoid power. We also consider the relationship between power aversion and responsibility aversion and suggest a convergence between research on responsibility aversion and lay theories of power.
Differences in feather structure between urban and forest great tits: constraint or adaptation?
Authors: Sándor Krisztina , Seress Gábor , Sinkovics Csenge , Péter Áron , Liker András
Published: February 2022

Urbanization is one of the strongest habitat transforming processes today that has resulted in changes in the ecological conditions for wild populations. In birds, the limitation of natural food sources and a warmer microclimate in cities can potentially influence the development and functioning of the plumage that may have important fitness consequences. Despite its potential significance, the plumage structure of urban birds are largely unexplored and it is unclear whether and how they respond to urban ecological processes such as different constraints and selection pressures. In this study, we compared several structural properties of contour, primary and tail feathers between two forest and two urban great tit Parus major populations. Our results show that the urban environment affects only a few structural properties of feathers and only in the plumage of first‐year birds. We found that both the plumulaceous and the pennaceous parts of their contour feathers are longer and have lower barb density in the urban than in the forest habitat. We also found that the primaries of first‐year birds have narrower rachis and higher barbule density in the cities than in the forests, but there were no differences in other wing feather traits and in any tail feather traits between habitats. We did not find differences in the feather structure of urban versus forest adult birds. The habitat differences in first‐year birds may indicate nutritional constraints or the effects of the warmer microclimate of the urban environment. These differences seem to disappear completely in adulthood that can be explained by the selective mortality of first‐year birds, or by adults being less sensitive than first‐year birds to environmental effects during their moult.
Photoperiod‐independent diapause‐inducing thermal response of Trichogramma larvae: Pattern and mechanisms
Authors: Reznik Sergey , Voinovich Natalia
Published: February 2022

It is well known that photoperiodic induction of insect diapause can be affected by temperature, whereas photoperiod‐independent diapause‐inducing thermal responses received much less attention of researchers. We studied the influence of a wide range (from 3 to 30°C) of constant and alternating temperatures on the rate of development, on pre‐adult survival and on the induction of pre‐pupal diapause in the egg parasitoid Trichogramma telengai. The progeny of females developed at 20°C and photoperiod of L:D = 18:6 or 12:12 was used in this study. The study showed that the pattern of the thermal response of T. telengai is an asymmetric inverted U‐shaped curve determined by two different mechanisms. The right part of the curve represents S‐shaped effect of temperature on the induction of diapause (the threshold for this response is 13–15°C depending on maternal photoperiod), whereas the left part represents an arrest of development caused by the direct effect of low temperature (with the threshold of about 5°C). We conclude that the effect of temperature on the induction of diapause in T. telengai is based on (or at least closely connected with) the thermal influence on the rate of metabolism and development. The results of this study can be used for the prediction of Trichogramma diapause incidence under natural conditions and for the development of the cold storage methods.
Women Electing Oocyte Cryopreservation: Characteristics, Information Sources, and Oocyte Disposition: A Systematic Review
Authors: Giannopapa Maria , Sakellaridi Anna , Pana Anastasia , Velonaki Venetia Sofia
Published: February 2022

Introduction

Recently, there is a growing interest in cryopreservation for nonmedical reasons, widely known as planned oocyte cryopreservation. This review aims to summarize and understand the characteristics of women who undergo or consider planned oocyte cryopreservation, identify their initial sources of information, and describe the oocyte disposition. This information should assist health professionals with shared decision‐making.

Methods

A systematic review was performed and reported following the Preferred Reporting Items for Systematic reviews and Meta‐Analyses (PRISMA) recommendations. PubMed, Scopus, and Web of Science were searched from inception to January 2021 without any limitation on publication date. Studies were included if they were in English and examined the characteristics of users or potential users of planned oocyte cryopreservation, initial information sources, and the oocyte disposition. Extracted data were analyzed using thematic analysis. The methodological quality of the recruited studies was assessed with the QualSyst criteria.

Results

Of 1074 initially retrieved records, 29 met the inclusion criteria, including 12 qualitative and 17 quantitative studies. Response rates of surveys ranged between 38% and 85%. Most of the users or potential users of planned oocyte cryopreservation were single, highly educated, and employed and had a mean age of 37 years. Media and friends were the most common sources of initial knowledge about planned oocyte cryopreservation, and health professionals were a less common source. The majority of planned oocyte cryopreservation users did not attempt pregnancy with their frozen oocytes, yet they did not regret having undergone the procedure. The results regarding the disposition intentions of unused frozen oocytes are inconsistent.

Discussion

Most of the users or potential users of planned oocyte cryopreservation have specific demographic characteristics and do not ultimately use their cryopreserved oocytes. Unused oocytes can be discarded or donated to other women or to research. By understanding the main characteristics of potential users of planned oocyte cryopreservation, health professionals can provide proper counseling and support effective decision‐making.
Efficacy of a topical serum containing L‐ascorbic acid, neohesperidin, pycnogenol, tocopherol, and hyaluronic acid in relation to skin aging signs
Authors: Neves Juliane Rocio , Grether‐Beck Susanne , Krutmann Jean , Correia Priscila , Gonçalves José Euzébio , Sant’Anna Beatriz , Kerob Delphine
Published: February 2022

Background

Skin aging is a process regulated by chronological aging and amplified by exposome factors including chronic UV exposure and pollution, which both induce reactive oxygen species. Topical antioxidants have the potential to counteract this process and to improve skin aging signs, including wrinkles and hyperpigmentation.

Objective

To evaluate the efficacy of a topical antioxidant serum containing 15% L‐ascorbic acid, neohesperidin, Pinus pinaster bark, tocopherol, and hyaluronic acid (HA) ex vivo on air pollution‐induced pigmentation and gene expression, as well as in vivo on skin aging signs in Brazilian volunteers, after 90 days of use.

Methods

Ex vivo human skin samples were repetitively exposed to Diesel Exhaust Particles (DEP) and subsequently analyzed for changes in pigmentation and gene expression. Clinical efficacy was evaluated in 40 healthy adult females with phototype II to IV and visible photoaging signs, including facial hyperpigmentation, through dermatological evaluation and instrumental analysis including Reflectance Confocal Microscopy.

Results

Ex vivo, the topical antioxidant serum significantly reduced DEP‐induced skin pigmentation and expression of proinflammatory genes. A significant improvement of skin aging signs was observed after 90 days. Local tolerance was good.

Conclusion

The tested serum is effective in protecting human skin ex vivo against air pollution‐induced skin pigmentation/aging and reduced in vivo skin aging signs, with a good safety profile after 90 days of daily use.
A retrospective analysis of the uses of BoNT‐A in daily dermatological practice
Authors: Hügül Hüray , Özkoca Defne , Kutlubay Zekayi
Published: February 2022

Introduction

Botulinum toxin‐A (BoNT‐A) has been increasingly used in the cosmetic dermatology daily routine. The treatment areas of BoNT‐A are glabellar lines, forehead wrinkles, periorbital lines (crow's feet), eyebrow lifting, perioral lines, platysmal bands, masseter hypertrophy, and hyperhidrosis. The aim of this study was to reveal the epidemiologic characteristics of the patients treated with BoNT‐A and the frequencies of treatment areas.

Patient and Methods

The patients were grouped into five categories: facial wrinkles, platysmal bands, masseter hypertrophy, axillary hyperhidrosis, and palmoplantar hyperhidrosis. Each patient received either onabotulinum toxin‐A (diluted with 2 cc saline) or abobotulinum toxin‐A (diluted with 3 cc saline) treatment. The patients' age, gender, and the total numbers of treatment received in each area were noted. SPSS version 21 was used for the statistical analysis.

Results

A total of 1614 patients were included: 165 (6.5%) male and 1509 (93.5%) female. There is no difference between genders in terms of treatment area (p = 0.855). The number of treatment sessions is independent of the patients’ gender (p = 0.703). The mean age of the patients was 46.6 years. There is a relationship between the patients’ age and treatment area (sig 0.000). There is no relationship between the number of repetitive treatments and the patients’ age (p=0.081). The number of repetitive treatments is dependent to the treatment area (p < 0.001).

Conclusion

Facial wrinkles, platysmal bands, and masseter hypertrophy are the most commonly treated areas. The treatment area is dependent on the age as platysmal bands are more commonly treated in older patients; however, no relationship between gender and treatment area was found. BoNT‐A treatment for hyperhidrosis is not as commonly repeated as for that of cosmetic concerns.
BesidesTongzhi: Tactics for Constructing and Communicating Sexual Identities in China
Authors: Zhou Zhiqiu Benson
Published: February 2022

Through examining queer men’s labeling practices, this paper illuminates the competing system of constructing and communicating queer identities in China. My research demonstrates that, in addition to relying on the termtongzhi, Chinese queer men have deployed three labeling tactics to make sense of distinct male homosexualities, using a wide range of slang terms. I argue that these tactics reveal the internal division and hierarchization on the basis of generation, class, self‐acceptance, and affective presentation, among other distinctions. Queer men deploy certain labels to draw symbolic boundaries of separation from other queer men and to construct ideal or superior sexual selfhood. Examining the labeling practices of queer men helps us better understand how queer communities both resist external categorization and create internal marginalization.
Labour is labour: what surrogates can learn from the Sex Work Is Work movement
Authors: ARMSTRONG SYLVIE
Published: February 2022

Though it is widely accepted that United Kingdom (UK) surrogacy laws are in need of reform, how they should be reformed remains a matter of considerable disagreement. This article explores a new regulatory suggestion: labour law. Building on the extensive sociological and anthropological literature that has conceptualized contract pregnancy as a form of work, it considers whether and how this might translate into a new regulatory framework, drawing on the Sex Work Is Work movement for inspiration. Though recognizing that this would require substantial changes to some of the present features of UK surrogacy law, it shows that there may be significant potential in this pre‐existing set of protections, improving the position of surrogates without dramatically changing the culture of the practice.
Association between sleep bruxism, use of antidepressants, and obstructive sleep apnea syndrome: A cross‐sectional study
Authors: Massahud Maria Letícia de Barros , Bruzinga Fábio Fernandes Borém , Diniz Silvana Alkmim de Miranda , Seraidarian Karolina Kristian de Aguilar , Lopes Regina de Magalhães , Barros Vinícius de Magalhães , Seraidarian Paulo Isaias
Published: February 2022

Background

Sleep bruxism (SB) is a condition regulated centrally, with a multifactorial etiology, which can occur secondary to systemic disorders and the use of certain medications.

Objective

The aim of this study was to identify associations between SB, obstructive sleep apnea, and hypopnea syndrome (OSAHS) and the use of antidepressants.

Material and Methods

In this cross‐sectional study, 240 individuals underwent full‐night polysomnography for medical reasons. Anamnesis was performed to collect data about the use of antidepressants and general health conditions. Polysomnography was performed to analyse sleep data and assess respiratory‐related events and apnea and hypopnea index (AHI). The polysomnographic assessment of SB was performed, from electrodes placed on masseter muscles and chin. SB was defined by the presence of more than two events of rhythmic masticatory muscles activity per hour of sleep. Statistical analyses were performed to compare the presence of SB and AHI, the severity of OSAHS, and the use of antidepressants.

Results

There were statistically significant differences between bruxers and non‐bruxers when comparing AHI (48.28 ± 25.84; p = .001) and severity of OSAHS (p = .015). Regarding the use of antidepressants, comparative analyses did not show correlations with bruxism (p = .072). However, logistic regression suggests that the use of these medications may represent increased odds for SB development (OR =2.387; p = .005).

Conclusion

The relationship between the use of antidepressants and SB remains inconclusive. SB is associated with OSAHS, mainly in its severe form. Therefore, identifying SB can raise the suspicion of the occurrence of other systemic disturbances.
The meanings of tolerance: Discursive usage in a case of ‘identity politics’
Authors: Verkuyten Maykel
Published: February 2022

The notion of tolerance is widely embraced across many settings and is generally considered critical for the peaceful functioning of plural societies, and within organizations, institutions, and many professions. However, the concept of tolerance has various meanings and can be discursively used in different ways and for different purposes. The various understandings and their usage can have different implications for normative views and real‐world decision making. This paper focuses on two main understandings of tolerance and how these are flexibly used in a debate about the case in which a social work student was excluded from further study by an university committee. This case serves as a particular illumination of the broader societal context of ‘cultural wars’ and ‘identity politics’ in which the notion of tolerance features prominently. It is examined how those who did and did not support the university decision deployed in different ways the notion of tolerance. It is concluded that tolerance has different cultural meanings which can be used for various ends in debates about contentious issues and for justifying or criticizing impactful decisions.
Interembodiment, Inheritance, and Intergenerational Health
Authors: Bunkley Emma Nelson
Published: February 2022

This article introduces the concept of interembodiment, animated bodily entanglements between people, to illustrate the shared sense of illness that transgresses discrete biological bodies. Drawing on 15 months of ethnographic research in Senegal, West Africa, this article expands common understandings of inheritance and intergenerational health by exploring how women caring for others with metabolic disorders come to interembody the afflicted's symptoms, regardless of their own diagnostic status. These experiences trouble the clear distinction between communicability and noncommunicability and disrupt Western understandings of unshared biologies. Through the concept of interembodiment, we can see how noncommunicable diseases come to be communicated. Interembodiment helps explain aspects of intergenerational health between mothers and daughters and allows for broader understandings that encompass multiple biologies. Shifting the focus of health and illness from the individual to multiple interembodied biologies allows for a more nuanced understanding of disease and disease transmission, which could enable global health and public health programs to better address noncommunicable diseases around the world.
Pediatric spinal anesthesia at a tertiary care hospital: Eleven years after
Authors: Eizaga Rebollar Ramón , García Palacios María Victoria , Morales Guerrero Javier , Torres Morera Luis Miguel
Published: February 2022

Background

Pediatric spinal anesthesia is an old technique whose use is not widespread, in spite of reducing the risk of cardiorespiratory events (hypoxemia, bradycardia, and hypotension) associated with general anesthesia, especially in neonates and infants. This retrospective cohort study aimed to assess the safety and effectiveness of the pediatric spinal anesthesia program at our tertiary care hospital over 11 years.

Methods

Two hundred children, between 8 days and 13 years of age, who underwent lower body surgery under spinal anesthesia from May 2010 to July 2021 were included. Demographic and procedural data were collected, and success, failure, and complication rates calculated.

Results

The success rate was 97.5% (n = 195). The incidence of complications was 2% (n = 4). They were 2 cases of intraoperative hypoxemia and 2 cases of postoperative postdural puncture headache , and they quickly resolved with no sequelae.

Conclusion

Pediatric spinal anesthesia is a safe and effective technique with good acceptance among anesthesiologists. Thus, the implementation of a pediatric spinal anesthesia program at a tertiary care hospital is feasible and affordable.
Morbidity and mortality following noncardiac surgical procedures among children with autosomal trisomy
Authors: Matthews Leslie J. , Mpody Christian , Nafiu Olubukola O. , Tobias Joseph D.
Published: February 2022

Background

Trisomy 13 (T13), trisomy 18 (T18), and trisomy 21 (T21) are the most common autosomal trisomies. One unifying feature of all trisomies is their association with major congenital malformations, which often require life‐prolonging surgical procedures. Few studies, mostly among cardiac surgery patients, have examined the outcome of those who undergo surgical procedures. We examined the differences in postsurgical outcomes between the trisomy groups.

Method

Using the National Surgical Quality Improvement Program dataset, we identified children (<18 years of age) with T13, T18, or T21 who underwent noncardiac surgery (2012–2018). We estimated the incidence of mortality and indicator of resource utilization (unplanned reoperation, unplanned tracheal reintubation, and extended length of hospital stay).

Results

Of the 349 158 inpatient surgical cases during the study period, we identified 4202 children with one of the autosomal trisomies of interest (T13: 152; T18: 335; and T21: 3715). The rates of postoperative mortality were substantially higher for T18 and T13 than T21 and nontrisomy children (T18 vs. T21: 11.1% vs. 1.6%, adjusted odds ratio: 5.01, 95%CI: 2.89,8.70, p < .01), (T13 vs. T21: 8.1% vs. 1.6%, adjusted odds ratio: 2.86, 95%CI: 1.25,6.54, p = .01). Children with T18 had the highest rates of extended length of stay (62.7%) and prolonged mechanical ventilation (32.5%). T18 and T13 neonates had the highest surgical mortality burden (T13: 26.5%, T18: 31.8%, and T21: 2.8%).

Conclusion

Approximately, one‐third of T18 and T13 neonates, who had surgery, died, underscoring the lethality of these trisomies and the need for a comprehensive preoperative ethical discussion with families of these children.
Genome‐wide association study for yield‐related traits in sesame (Sesamum Indicum)
Authors: Tesfaye Tewodros , Tesfaye Kassahun , Keneni Gemechu , Alemu Tesfahun , Alemu Admas
Published: February 2022

Sesame is an important oil crop in Ethiopia and other regions in terms of both area coverage and production. However, productivity is low due to biotic and abiotic stresses. Therefore, dissecting the genetic basis of quantitatively inherited yield‐related traits is instrumental to developing stable and high‐yielding varieties. A genome‐wide association study (GWAS) was performed with a diverse set of 300 sesame accessions tested in two environments and 2997 SNP markers. In total, 21 significant marker–trait associations (MTAs) were detected for seven yield‐related traits, including days to flower initiation (DFI), days to 50% flowering (DF), days to physiological maturity (DM), capsule length (CAPL), seeds per capsule (SPC), 1000‐seed weight (TSW) and bacterial blight (BBL). The majority of MTAs detected on LG 3, 7 and 8 were associated with traits related to physiological periods. Dissecting genetic control of flowering time and maturity has a pivotal contribution to fostering sesame breeding and developing new varieties adaptable to changing climatic conditions. Our GWAS results will assist in incorporating alleles into the elite sesame germplasm through marker‐assisted selection.
Pausing transplants in the face of a global pandemic: Patient survival implications
Authors: Zhang Minmin , Wang Guihua , Li Jun , Hopp Wallace J. , Lee David D.
Published: February 2022

The coronavirus disease 2019 (COVID‐19) pandemic has disrupted normal operating procedures at transplant centers. With the possibility that COVID‐19 infection carries an overall 4% mortality rate and potentially a 24% mortality rate among the immunocompromised transplant recipients, many transplant centers considered the possibility of slowing down and even potentially pausing all transplants. Many proposals regarding the need for pausing organ transplants exist; however, much remains unknown. Whereas the impact of the COVID‐19 pandemic on the overall healthcare system is unknown, the potential impact of pausing organ transplants over a period can be estimated. This study presents a model for evaluating the impact of pausing liver transplants over a spectrum of model for end‐stage liver disease‐sodium (MELD‐Na) scores. Our model accounts for two potential risks of a pause: (1) the waitlist mortality of all patients who do not receive liver transplants during the pause period, and (2) the impact of a longer waiting list due to the pause of liver transplants and the continuous accrual of new patients. Using over 12 years of liver transplant data from the United Network for Organ Sharing and a system of differential equations, we estimate the threshold probability above which a decision maker should pause liver transplants to reduce the loss of patient life months. We also compare different pause policies to illustrate the value of patient‐specific and center‐specific approaches. Finally, we analyze how capacity constraints affect the loss of patient life months and the length of the waiting list. The results of this study are useful to decision makers in deciding whether and how to pause organ transplants during a pandemic. The results are also useful to patients (and their care providers) who are waiting for organ transplants.
Another organization is possible: New directions in research on alternative enterprise
Authors: Spicer Jason , Kay Tamara
Published: February 2022

Interest in alternative enterprises is again high, yielding a wave of popular experimentation with alternative organizational models, and new scholarship. From an organizational studies perspective, what have we learned about alternative enterprises since the last prior round of such experimentation in the 1970s, and what questions remain unanswered? Reflecting historical research legacies, scholarship often remains focused on micro‐aspects of internal organizational dynamics, but recent research at the meso scale has advanced our understanding of alternatives’ field‐level construction, and their relationship to external forces and other organizational forms. Less is known, however, at the macro scale about how or why these enterprises develop and are sustained in certain contexts, although work on this front is emerging. Meanwhile, many new alternative organizational forms/practices have not been well‐studied. Future research can remedy this oversight, while also seeking to improve our understanding of the effect of external, macro and meso‐scaled dynamics of alternative enterprises. It can also seek to better explain variations in alternatives’ institutional development and effectiveness in different sectoral contexts and domains, most notably across today’s crisis‐related fronts of climate change, housing precarity, and technological change. In so doing, it could more directly speak to a rising generation’s concerns, and better enable their effective deployment of alternatives in practice.
Bridging theories of social and revolutionary movements
Authors: Duarte‐Mayorga Natalia
Published: February 2022

How can theories of social movements and revolutions help us understand the rise of collective action, their tactical and strategic choices, and their prospects for succeeding? By reviewing past and recent developments in the literature of social movements and revolutions, I argue that in comparison with social movements scholars, structuralists of revolutions more accurately used theories of threat and breakdown in understanding what triggers revolutions and revolutionary situations. Nevertheless, because scholars of revolutions usually distinguish types of revolutions based on outcomes after supposed clear endings, they have missed important insights from the literature on movement continuity that might guide us towards new understandings of revolutions. Moreover, both fields have followed similar paths in terms of contributions and gaps in the study of emotions, spontaneity, tactics, and repression in collective action.
Identification of the novel HLA‐A*23:01:01:27 allele in an acute myeloid patient and related donor
Authors: Bastos Miguel , Alcoceba Miguel , Chillón María Carmen , García‐Sanz Ramón , Boix Francisco
Published: February 2022

A single nucleotide polymorphism in intron 1 determines the new HLA‐A*23:01:01:27 allele.
Identification of the novel allele, HLA‐DRB1*08:03:12, in a Chinese cord blood donor
Authors: Fu Rui , Wang Fang , Zhao Shuoxian , Zhang Wei , Zhu Faming
Published: February 2022

HLA‐DRB1*08:03:12 differs from HLA‐DRB1*08:03:02 by a single nucleotide substitution at position 702C>T.
From Magnitudes to Geometry and Back: De Zolt's Postulate
Authors: Giovannini Eduardo N. , Lassalle‐Casanave Abel
Published: February 2022

A crucial trend of nineteenth‐century mathematics was the search for pure foundations of specific mathematical domains by avoiding the obscure concept of magnitude. In this paper, we examine this trend by considering the “fundamental theorem” of the theory of plane area: “If a polygon is decomposed into polygonal parts in any given way, then the union of all but one of these parts is not equivalent to the given polygon.” This proposition, known as De Zolt's postulate, was conceived as a strictly geometrical expression of the general principle of magnitudes “the whole is greater than the part.” On the one hand, we illustrate this striving for purity in the foundations of geometry by analysing David Hilbert's classical proof of De Zolt's postulate. On the other hand, we connect this geometrical problem with the first axiomatizations of the concept of magnitude by the end of the nineteenth century. In particular, we argue that a recent result in the logical analysis of the concept of magnitude casts new light on Hilbert's proof. We also outline an alternative development of a theory of magnitude that includes a proof of De Zolt's postulate in an abstract setting.
Improvements in liver transplant outcomes in patients with HCV/HIV coinfection after the introduction of direct‐acting antiviral therapies
Authors: Shimada Shingo , Ivanics Tommy , Kitajima Toshihiro , Shamaa Tayseer , Rizzari Michael , Collins Kelly , Yoshida Atsushi , Abouljoud Marwan , Moonka Dilip , Zhang Jiaqi , Lu Mei , Nagai Shunji
Published: February 2022

Background

In recipients with HCV/HIV coinfection, the impact that the wider use of direct‐acting antivirals (DAAs) has had on post‐liver transplant (LT) outcomes has not been evaluated. We investigated the impact of DAAs introduction on post‐LT outcome in patients with HCV/HIV coinfection.

Methods

Using Organ Procurement and Transplant Network/United Network for Organ Sharing data, we compared post‐LT outcomes in patients with HCV and/or HIV pre‐ and post‐DAAs introduction. We categorized these patients into two eras: pre‐DAA (2008‐2012 [pre‐DAA era]) and post‐DAA (2014–2019 [post‐DAA era]). To study the impact of DAAs introduction, inverse probability of treatment weighting was used to adjust patient characteristics.

Results

A total of 17 215 LT recipients were eligible for this study (HCV/HIV [n = 160]; HIV mono‐infection [n = 188]; HCV mono‐infection [n = 16 867]). HCV/HIV coinfection and HCV mono‐infection had a significantly lower hazard of 1‐ and 3‐year graft loss post‐DAA, compared pre‐DAA (1‐year: adjusted hazard ratio [aHR] 0.29, 95% confidence interval (CI) 0.16–0.53 in HIV/HCV, aHR 0.58, 95% CI 0.54–0.63, respectively; 3‐year: aHR 0.30, 95% CI 0.14–0.61, aHR 0.64, 95% CI 0.58–0.70, respectively). The hazards of 1‐ and 3‐year graft loss post‐DAA in HIV mono‐infection were comparable to those in pre‐DAA. HCV/HIV coinfection had significantly lower patient mortality post‐DAA, compared to pre‐DAA (1‐year: aHR 0.30, 95% CI 0.17–0.55; 3‐year: aHR 0.31, 95% CI 0.15–0.63).

Conclusions

Post‐LT outcomes in patients with coinfection significantly improved and became comparable to those with HCV mono‐infection after introducing DAA therapy. The introduction of DAAs supports the use of LT in the setting of HCV/HIV coinfection.
Cryptosporidium parvum outbreak associated with Raccoons at a Wildlife Facility—Virginia, May–June 2019
Authors: Davis Meredith K. , Riley Jennifer , Darby Brandy , Murphy Julia , Turner Lauren , Segarra Marta D. , Roellig Dawn M.
Published: February 2022

Cryptosporidium parvum is a parasitic zoonotic pathogen responsible for diarrheal illness in humans and animals worldwide. We report an investigation of a cryptosporidiosis outbreak in raccoons and wildlife rehabilitation workers at a Virginia facility. Fifteen (31%) of 49 facility personnel experienced symptoms meeting the case definition, including four laboratory‐confirmed cases. Seven juvenile raccoons were reported to have diarrhoea; six had laboratory‐confirmed cryptosporidiosis. Cryptosporidium parvum of the same molecular subtype (IIaA16G3R2) was identified in two human cases and six raccoons. Raccoon illness preceded human illness by 11 days, suggesting possible zoonotic transmission from raccoons to humans. This appears to be the first report of a human cryptosporidiosis outbreak associated with exposure to raccoons infected with C. parvum. Raccoons might be an under‐recognized reservoir for human C. parvum infections. Further study is needed to explore the prevalence of cryptosporidial species in raccoons and their role as a wildlife reservoir.
Psychosocial Correlates of Stress among International and American Students
Authors: Srinivasa Susheelabai
Published: February 2022

Student life in college tends to be stressful since it entails a variety of demands and challenges. Academic demands and psychosocial factors cause stress in students, besides compounding factors like personal commitments, life events, and inadequate social and economic supports in pursuing college education. This study investigated academic stress among international students (N=90) in comparison to American students (N=131) and identified the psychosocial correlates of stress using the Gadzella’s SLSI. Furthermore, this study not only portrayed the characteristics of international students but also determined the predictors of stress from among factors like social support or social provision, social desirability, and general health. This study concluded that both American (domestic) and international students experience stress. American (domestic) students were found to have higher levels of stress. However, cultural factors of international students are intertwined with the perception and expression of emotions relating to stress and mental health. The study recommends that higher educational institutions should beef up support services such as counseling to deal with stress, time management, wellness and mental health, and guidance about campus support services. Further research is needed on student stress comparing these two groups.
The C2 domains of dysferlin: roles in membrane localization, Ca2+ signalling and sarcolemmal repair
Authors: Muriel Joaquin , Lukyanenko Valeriy , Kwiatkowski Tom , Bhattacharya Sayak , Garman Daniel , Weisleder Noah , Bloch Robert J.
Published: February 2022

Dysferlin is an integral membrane protein of the transverse tubules of skeletal muscle that is mutated or absent in limb girdle muscular dystrophy 2B and Miyoshi myopathy. Here we examine the role of dysferlin's seven C2 domains, C2A through C2G, in membrane repair and Ca2+ release, as well as in targeting dysferlin to the transverse tubules of skeletal muscle. We report that deletion of either domain C2A or C2B inhibits membrane repair completely, whereas deletion of C2C, C2D, C2E, C2F or C2G causes partial loss of membrane repair that is exacerbated in the absence of extracellular Ca2+. Deletion of C2C, C2D, C2E, C2F or C2G also causes significant changes in Ca2+ release, measured as the amplitude of the Ca2+ transient before or after hypo‐osmotic shock and the appearance of Ca2+ waves. Most deletants accumulate in endoplasmic reticulum. Only the C2A domain can be deleted without affecting dysferlin trafficking to transverse tubules, but Dysf‐ΔC2A fails to support normal Ca2+ signalling after hypo‐osmotic shock. Our data suggest that (i) every C2 domain contributes to repair; (ii) all C2 domains except C2B regulate Ca2+ signalling; (iii) transverse tubule localization is insufficient for normal Ca2+ signalling; and (iv) Ca2+ dependence of repair is mediated by C2C through C2G. Thus, dysferlin's C2 domains have distinct functions in Ca2+ signalling and sarcolemmal membrane repair and may play distinct roles in skeletal muscle.

Key points

Dysferlin, a transmembrane protein containing seven C2 domains, C2A through C2G, concentrates in transverse tubules of skeletal muscle, where it stabilizes voltage‐induced Ca2+ transients and participates in sarcolemmal membrane repair.

Each of dysferlin's C2 domains except C2B regulate Ca2+ signalling.

Localization of dysferlin variants to the transverse tubules is not sufficient to support normal Ca2+ signalling or membrane repair.

Each of dysferlin's C2 domains contributes to sarcolemmal membrane repair.

The Ca2+ dependence of membrane repair is mediated by C2C through C2G.

Dysferlin's C2 domains therefore have distinct functions in Ca2+ signalling and sarcolemmal membrane repair.
La pandemia de COVID-19 en Colombia y los desafíos de la respuesta sanitaria
Authors: Hernández-Bello Amparo , Agudelo-Londoño Sandra Milena
Published: February 2022

Presentación del Dossier especial COVID-19
Specific Heats of Liquid Metals and Liquid Salts
Authors: Douglas T. B.
Published: February 2022

In view of the general use of liquid metals and liquid salts in heat-transfer systems at high temperatures, their specific heats are reviewed. First, the general method of measuring them is described, and the more important sources of error are discussed. Known data are then examined on a volume basis, and two examples are presented which bear on the relation of the specific heats of mixtures to those of their components. It is finally shown that the specific heats of most liquid metals and liquid salts, when converted to an atomic basis, appear to be sufficiently alike to justify an approximate prediction in many cases for which no data exist.
Fuel Elements for Nuclear Reactors
Authors: Anderson J. B.
Published: February 2022

A general discussion is presented of the basic requirements for fuel elements for nuclear reactors and of the heat-transfer characteristics affecting the selection of a fuel element design. This is followed by a presentation of typical fuel elements along with a discussion of their potential performance and applicability in line with the basic requirements and heat-transfer factors discussed earlier.
Creep Damage in a Cr-Mo-V Steel as Measured by Retained Stress Rupture Properties
Authors: Jones M. H. , Newman D. P. , Brown W. F.
Published: February 2022

It is well known that a material subjected to progressive creep eventually fractures at a time determined by the applied stress and temperature. However, the processes which exhaust the metal ductility in creep are very poorly understood. Until these processes are clearly defined it is not possible to arrive at a satisfactory fracture theory for creep nor is it possible to predict intelligently the effects of creep history on the rupture life.

In this investigation the progressive metal deterioration occurring during creep at 1000 F is measured by the retained 1100 F stress-rupture properties. This “creep damage” is shown to be both strain and time-sensitive. The creep conditions producing large damages are defined and a mechanism for the damage suggested. It is also shown that reheat treatment is able to heal the most severe damages produced in this investigation.
Plant Management and Other Factors Affecting Maintenance Costs in Steam-Generating Stations
Authors: Estcourt V. F.
Published: February 2022

Although direct maintenance costs in thermal power stations comprise only a small percentage of the total cost of production, replacement power costs while a generating unit is out of service for maintenance are also chargeable to the over-all cost of the job. This may amount to considerably more than the entire cost of the repairs. The control of maintenance costs is concerned principally with those factors which influence the ability of the plant to stay on the line, and this includes a wide variety of problems relating to equipment design, plant layout, types of fuels, manpower utilization, and other management problems. The limited statistical value of the term “operating availability” is discussed, and the concept of “relative mechanical availability” is introduced. Increasing technical and physical complications, together with larger unit sizes and greatly expanded generating systems, suggests the need for a redistribution of responsibilities at the plant level. This has created a demand for higher-grade engineering graduates with academic qualifications more suited to the special problems of thermal-power production, and a larger degree of co-operative effort between the utilities and the universities.
Experimental Superheater for Steam at 2000 Psi and 1250 F—Report After 14,281 Hours of Operation
Authors: Hoke J. H. , Eberle F.
Published: February 2022

In order to investigate the reactions of superheater alloys to operating conditions producing steam at 1250 F, a test element constructed of 2-in-OD alloy tubes was installed in an operating boiler at the Twin Branch Plant. Operating conditions and experience after 5000 and 12,000 hr as well as metallurgical examination of specimens removed from the element after nearly 7000 hr of operation were described in previous papers. The present paper describes the results of the metallurgical examinations after 14,281 hr of operation, when the experiment was discontinued and the test element removed for complete examination and evaluation.
High-Temperature Corrosion of Alloys Exposed in the Superheater of an Oil-Fired Boiler
Authors: McDowell D. W. , Raudebaugh R. J. , Somers W. E.
Published: February 2022

A series of heat-resistant alloy test racks containing some 30-odd test specimens was installed in the gas inlet of the second bank of the superheater in a Public Service Electric and Gas Company boiler. This boiler had been burning bunker C fuel oil for the three-year period before the test and used bunker C during the entire test period. Gas temperatures varied from 1560 F at full load to 1100 F at minimum load. The loading on the boiler during the investigation was considered typical of steam-boiler operation. Scale taken from the build-up on the test specimens analyzed as high as 36 per cent vanadium pentoxide and 32 per cent sulphuric anhydride. An analysis of the ash constituents present in the oil-fired boiler during the tests also showed high vanadium, sulphur, sodium, and calcium contents. All corrosion rates were measured by metallographic examination and were expressed as inches penetration for the duration of the test and extrapolated to inches per year (IPY). Corrosion results were obtained on both cast and wrought alloys as well as some alloys with various coatings. An extensive metallographic investigation was conducted on all alloys exposed to determine the type of attack each material underwent during the exposure period. Some alloys had a corrosion rate as much as ten times greater than others.
The Spring-Supported Thrust Bearing
Authors: Osterle Fletcher , Saibel Edward
Published: February 2022

The slider bearing with the bearing a flexible plate mounted on springs is analyzed for its load-carrying characteristics. The deflection of the plate under load is found to create a wedge effect in the lubricant film which acts in conjunction with the wedge due to the inclination of the slider in producing a load capacity. The effect of the deflection of the bearing plate on the load capacity can be significant as is illustrated by a numerical example.
Instrumentation for Steam-Consumption Tests on Medium Steam Turbine-Generator Sets
Authors: Kimball D. E.
Published: February 2022

In a 1954 paper (1) we presented various measures of the uncertainties of the data of precision steam-consumption tests on medium-sized steam turbine-generator sets, deriving them from the over-all results of the tests and from comparisons of duplicate instruments used in them. In the present paper we describe briefly the instruments and their calibrations, and we present typical calibration corrections. The instruments and their calibrations have been used for many years. Most comparisons presented here demonstrate that instruments of high precision have small calibration corrections which are significant and that most corrections do not change significantly. They also show that these instruments can be relied upon in very precise turbine steam-consumption tests.
Investigation of Causes of Low Wheel-to-Rail Adhesion and Possible Methods of Improving It
Authors: Fisher F. G. , Allen R. K.
Published: February 2022

Wheel-to-rail adhesion is fundamental to the operation of a railroad. The potentially high tractive effort of modern diesel-electric and electric locomotives has focused attention more sharply on conditions which limit adhesion. Train stalls, rail burns, flat wheels, and damaged electric traction equipment all point to the importance of the problem. Extensive tests have yielded much information on the causes of low adhesion and methods of improving it. The results indicate that running adhesions in excess of 26 per cent can be maintained by the application of certain materials to locomotive drivers or to the rail.
First Commercial Supercritical-Pressure Steam Turbine—Built for the Philo Plant
Authors: Elston C. W. , Sheppard R.
Published: February 2022

This paper describes the essential design features of a 125,000-kw, 3600-rpm, tandem-compound, double-flow steam turbine designed for steam conditions of 4500 psig, 1150 F initial temperature, 1050 F at the first reheat, and 1000 F at the second reheat. The engineering objectives, problems, and solutions are emphasized more than the description of design details.
Contributions to Hydraulic Control—7: Analysis of the Effects of Nonlinearity in a Valve-Controlled Hydraulic Drive
Authors: Reeves E. I.
Published: February 2022

A method is developed for analyzing the performance of a valve-controlled hydraulic drive consisting of a closed-center four-way valve, hydraulic motor, and mechanical load. This analysis facilitates the determination of the amplitude and phase of the fundamental component of load velocity in response to sinusoidal valve-spool motion and includes the effects of three sources of nonlinear performance: The pressure-flow characteristics of the valve, orifice-type hydraulic leakage, and nonlinear speed-dependent friction. The analysis is verified by analog-computer results and experimental data from an actual valve-controlled drive.