bluuebunny/crossref_metadata_2025_split huggingface dataset:
Naturally occurring variation in the restriction map of the amy region of Drosophila melanogaster.
Authors: Langley C H , Shrimpton A E , Yamazaki T , Miyashita N , Matsuo Y , Aquadro C F 
Published: January 2021

Abstract
The restriction maps of 85 alleles of the Amy region of Drosophila melanogaster from natural populations were surveyed. A subset of these were also scored for allozyme phenotype and adult enzyme activity of alpha-amylase. Large insertions were found in 12% of the alleles in a 15-kb region surrounding the two transcriptional units of the duplicated Amy locus. The low frequencies at which each of these large insertions were found are consistent with earlier reports of variation in other loci. Four small deletions were found in the region 5' to the Amy genes. Each was also rare in the population. Restriction site variation provided an estimate of per nucleotide heterozygosity of 0.006. Several statistically significant linkage disequilibria were observed between four polymorphic restriction sites and the allozymes. Adult alpha-amylase activity was correlated with the allozymes and with the polymorphism at one restriction site close to the transcriptional units.
Evolution of the autosomal chorion locus in Drosophila. I. General organization of the locus and sequence comparisons of genes s15 and s19 in evolutionary distant species.
Authors: Martínez-Cruzado J C , Swimmer C , Fenerjian M G , Kafatos F C 
Published: January 2021

Abstract
We have isolated clones corresponding to the autosomal chorion locus of Drosophila melanogaster, from two distantly (D. virilis and D. grimshawi) and one closely (D. subobscura) related species. In all the species the locus is unique within the genome and encompasses the same four chorion genes and an adjacent nonchorion gene, in the same order. In all species the locus specifically amplifies in the ovary, as in D. melanogaster. We present the nucleotide sequences of DNA segments that total 8.3 kb in length and include gene s15-1 from D. subobscura, D. virilis, and D. grimshawi as well as gene s19-1 from D. subobscura and D. grimshawi. They show clearly nonuniform rates of divergence, both within and outside the limits of the genes. Highlighted by a background of extensive sequence divergence elsewhere in the extragenic region, highly conserved elements are observed in the 5' flanking DNA and might represent regulatory elements.
Double-stranded gap repair of DNA by gene conversion in Escherichia coli.
Authors: Kobayashi I , Takahashi N 
Published: January 2021

Abstract
We demonstrated repair of a double-stranded DNA gap through gene conversion by a homologous DNA sequence in Escherichia coli. We made a double-stranded gap in one of the two regions of homology in an inverted orientation on a plasmid DNA molecule and introduced it into an E. coli strain which has the RecE system of recombination (genotype; sbcA23 recB21 recC22). We detected repair products by genetic selection. The repair products were those expected by the double-strand-gap repair model. Gene conversion was frequently accompanied by crossing over of the flanking sequences as in eukaryotes. This double-strand gap repair mechanism can explain plasmid recombination in the absence of an artificial double-stranded break reported in a companion study by Yamamoto et al.
The rosy region of Drosophila melanogaster and Drosophila simulans. I. Contrasting levels of naturally occurring DNA restriction map variation and divergence.
Authors: Aquadro C F , Lado K M , Noon W A 
Published: January 2021

Abstract
A 40-kb region around the rosy and snake loci was analyzed for restriction map variation among 60 lines of Drosophila melanogaster and 30 lines of Drosophila simulans collected together at a single locality in Raleigh, North Carolina. DNA sequence variation in D. simulans was estimated to be 6.3 times greater than in D. melanogaster (heterozygosities per nucleotide of 1.9% vs. 0.3%). This result stands in marked contrast to results of studies of phenotypic variation including proteins (allozymes), morphology and chromosome arrangements which are generally less variable and less geographically differentiated in D. simulans. Intraspecific polymorphism is not distributed uniformly over the 40-kb region. The level of heterozygosity per nucleotide varies more than 12-fold across the region in D. simulans, being highest over the hsc2 gene. Similar, though less extreme, variation in heterozygosity is also observed in D. melanogaster. Average interspecific divergence (corrected for intraspecific polymorphism) averaged 3.8%. The pattern of interspecific divergence over the 40-kb region shows some disparities with the spatial distribution of intraspecific variation, but is generally consistent with selective neutrality predictions: the most polymorphic regions within species are generally the most divergent between species. Sequence-length polymorphism is observed for D. melanogaster to be at levels comparable to other gene regions in this species. In contrast, no sequence length variation was observed among D. simulans chromosomes (limit of resolution approximately 100 bp). These data indicate that transposable elements play at best a minor role in the generation of naturally occurring genetic variation in D. simulans compared to D. melanogaster. We hypothesize that differences in species effective population size are the major determinant of the contrasting levels and patterns of DNA sequence and insertion/deletion variation that we report here and the patterns of allozyme and morphological variation and differentiation reported by other workers for these two species.
Genetic evidence that the sans fille locus is involved in Drosophila sex determination.
Authors: Oliver B , Perrimon N , Mahowald A P 
Published: January 2021

Abstract
Females homozygous for sans fille1621 (= fs(1)1621) have an abnormal germ line. Instead of producing eggs, the germ-line cells proliferate forming ovarian tumors or excessive numbers of nurse cells. The Sex-lethal gene product(s) regulate the branch point of the dosage compensation and sex determination pathways in the soma. The role of Sex-lethal in the germ line is not clear but the germ line of females homozygous for female sterile Sex-lethal alleles or germ-line clones of loss-of-function alleles are characterized by ovarian tumors. Females heterozygous for sans fille1621 or Sex-lethal are phenotypically wild type with respect to viability and fertility but females trans-heterozygous for sans fille1621 and Sex-lethal show ovarian tumors, somatic sexual transformations, and greatly reduced viability.
Genetic analysis of mouse t haplotypes using mutations induced by ethylnitrosourea mutagenesis: the order of T and qk is inverted in t mutants.
Authors: Justice M J , Bode V C 
Published: January 2021

Abstract
The t region of mouse chromosome 17 exhibits recombination suppression with wild-type chromatin. However, the region has resisted classical genetic dissection because of a lack of defined variants. Mutations induced by N-ethyl-N-nitrosourea (ENU) at the Brachyury (T), quaking (qk), and tufted (tf) loci of the mouse tw5 haplotype have now allowed the analysis of crossovers between two complete t haplotypes. A classical breeding analysis of the complete t haplotypes, tw5 and t12, utilizing the newly induced markers, reveals two inversions in t chromatin: one involving T and qk, and one involving tf and the H-2 complex. Moreover, the recombination frequency between the loci of T and qk is reduced compared to the frequency reported in normal chromatin. These two inversions are a sufficient explanation for the recombination inhibition with normal chromatin exhibited by t haplotypes isolated from the wild. Furthermore, the reduced recombination frequency between T and qk may indicate that the proximal gene rearrangement is not a simple inversion.
Maintaining Sense of Purpose Following Health Adversity in Older Adulthood: A Propensity Score Matching Examination
Authors: Hill Patrick L , Beck Emorie D , Jackson Joshua J 
Published: January 2021

Abstract

Objectives
Research has demonstrated sense of purpose predicts better health in older adulthood. However, work is limited with respect to understanding how experiencing a health event or illness diagnosis impacts older adults’ sense of purpose.

Method
The current study employed a propensity score matching approach to compare older adults who did or did not experience an adverse health event on changes in sense of purpose across 3 waves of the Health and Retirement Study. Sense of purpose was assessed at each wave, and changes were compared between people who did versus did not experience one of 7 diagnoses and health events.

Results
When propensity score matching was employed, no differences in trajectories of change for sense of purpose were found with respect to all 7 events. Individual differences in trajectories, however, were evidenced across groups.

Discussion
The current findings suggest that even when health events impact older adults’ physical functioning or place limitations on their activity, they may hold little ramifications for their sense of purpose. Future research should consider this potential for resilience, focusing on how adults compensate for losses.
Revisiting the Role of Gender and Marital Status as Risk Factors for Nursing Home Entry
Authors: Casanova Maria 
Published: January 2021

Abstract

Objective
To study the role of gender and marital status as risk factors for nursing home entry in the United States.

Method
The paper uses data from the Health and Retirement Study, a nationally representative survey of the older population in the United States. Multivariate logit models of the risk of nursing home entry over a 2-year follow-up period were estimated for noninstitutionalized individuals over the age of 65. A multiple imputation procedure was used to explore the sensitivity of the results to alternative assumptions about the data-generating process of missing outcome values.

Results
In an analysis based on complete observations, women exhibited the same risk of nursing home entry as men (risk ratio [RR] = 1.01; CI: 0.90, 1.13). However, after expanding the sample to include information on nursing home use for individuals who died during the follow-up period, women were found to have a statistically lower risk of nursing home entry (RR = 0.85; CI: 0.79, 0.92). The latter result was robust to alternative assumptions about the nature of missing data. The type of sample used in the analysis did not affect the conclusions regarding the role of marital status. Divorced and widowed individuals were found to be at higher risk of nursing home admissions than married individuals in all specifications.

Discussion
The findings clarify the role of gender as a predictor of nursing home admissions and may provide useful prognostic information for clinicians and caregivers regarding nursing home entry risk. The study also sheds light on how conclusions about predictors of nursing home risk obtained from prospective studies with long follow-up periods can be affected by the treatment of missing outcomes due to death or attritions.
Knowledge Exchanges and Decision-Making Within Hospital Dementia Care Triads: An Ethnographic Study
Authors: Kelley Rachael , Godfrey Mary , Young John 
Published: January 2021

Abstract

Background and Objectives
Important decisions about the future care of people living with dementia are routinely made in hospitals. Very little is known about how the care needs of hospitalized people with dementia are understood, or how the perspectives of the person, families, and staff intersect to inform decision-making. This study explores how the care needs of people with dementia are understood by the person, their family, and hospital staff (the care triad), and how these perspectives shape decision-making.

Research Design and Methods
Ethnographic data were collected from 2 care-of-older-people general hospital wards via observations, conversations, and interviews with people with dementia, families, and staff. In total, 400 hr of observation and 46 interviews were conducted across two 7- to 9-month periods.

Results
The person’s care needs were often understood differently between and within arms of the care triad. A lack of consistent engagement with families and people with dementia reduced opportunities to recognize and integrate this range of views, leading to delays or difficulties in decision-making. People with dementia, particularly those lacking capacity, were most likely to have their perspectives overlooked.

Discussion and Implications
Early engagement with people with dementia and their families is required to ensure that all perspectives on the person’s current and future care needs are understood and represented during decision-making. Particular attention should be paid to involving people living with dementia in discussions and decisions about their care, and to the assessment and involvement of people who may lack capacity.
Patient satisfaction with outpatient care in China: a comparison of public secondary and tertiary hospitals
Authors: Yan Jingjing , Yao Jiansen , Zhao Dahai 
Published: January 2021

Abstract

Objective
The aims of this study were to investigate and compare patient satisfaction with outpatient care in public secondary and tertiary hospitals in China and to explore the factors affecting patient satisfaction for improving the quality of outpatient care in public hospitals.

Methods
This cross-sectional study comprised a sample survey of 11 097 adults in 31 provincial cities in China from February to April 2018. A pretested structured questionnaire was used to collect outpatient experience data through a computer-assisted telephone interviewing system. Patient satisfaction was assessed using nine questions answered on a 4-point Likert scale. Multivariate regression models were employed to examine the relationships of patient satisfaction with outpatient services and healthcare provider level and to identify the factors associated with satisfaction.

Results
Patient’s overall satisfaction score with outpatient care was 27.3 (SD = 3.8), with lower scores observed in tertiary hospitals than in secondary hospitals (27.3 vs. 27.6, P &lt; 0.05). The domain with the highest satisfaction was ‘consulting environment’, and the domain with the lowest satisfaction was ‘patient waiting time in the hospital’. Patients who went to tertiary hospitals reported lower satisfaction in ‘patient waiting time in the hospital’, ‘medical expenses’, ‘patient length of treatment time’ and ‘attitudes of other health workers’ than patients who went to secondary hospitals (P &lt; 0.05). In secondary hospitals, no significant difference in patient satisfaction was observed between different sociodemographic categories (P &gt; 0.05). In tertiary hospitals, female and single respondents were more likely to have higher satisfaction (P &lt; 0.05), whereas respondents with high school or junior college degrees were more likely to have lower satisfaction (P &lt; 0.05).

Conclusion
The aforementioned results suggested that tertiary hospitals face larger challenges in patient satisfaction with outpatient care than secondary hospitals. Measures must be adopted to improve patient satisfaction with outpatient care in future healthcare reforms. Patient waiting time, medical expenses and treatment duration especially require improvements in tertiary hospitals.
An evidence-based oxytocin protocol for the third stage of labor to improve hemorrhage outcomes
Authors: Gonzalez Sara C , Budge Jeffrey , Butler Patricia D , Higgs Maureen , Whiting Judd , Lutgendorf Monica A 
Published: January 2021

Abstract

Objective
To assess the use of an evidence-based oxytocin protocol for management of the third stage of labor to decrease non-beneficial clinical variation and improve clinical outcomes.

Design
This is a cohort study of pregnant patients delivering before implementation of an evidence-based oxytocin protocol compared to patients delivering after implementation of an evidence-based oxytocin protocol.

Setting
A level III maternal care referral hospital with an average delivery volume of approximately 3000 deliveries.

Participants
Pregnant patients delivering over a 60-month period from January 2013 to December 2017.

Intervention
An evidence-based oxytocin protocol: 3 units of oxytocin administered over 3 minutes, with a second 3-unit bolus if inadequate tone, then oxytocin infusion at 18 units/hour × 1 hour and then 3.6 units/hour for 3 hours.

Main outcome measures
Postpartum hemorrhage (PPH) rate (EBL ≥500 ml for vaginal and ≥1000 ml for cesarean).

Results
Data from 14 603 deliveries were analyzed, 8408 pre-protocol and 6195 post-protocol. We demonstrated a significant decrease in PPH from 5.2% to 2.9% (P &lt; 0.001) and a small but non-significant increase in the transfusion rate from 1.8% to 2.3% (P = 0.11).

Conclusion
A standardized oxytocin infusion protocol in the third stage of labor resulted in a significant decrease in PPH for both vaginal and cesarean deliveries.
Quantification of abdominal fat from computed tomography using deep learning and its association with electronic health records in an academic biobank
Authors: MacLean Matthew T , Jehangir Qasim , Vujkovic Marijana , Ko Yi-An , Litt Harold , Borthakur Arijitt , Sagreiya Hersh , Rosen Mark , Mankoff David A , Schnall Mitchell D , Shou Haochang , Chirinos Julio , Damrauer Scott M , Torigian Drew A , Carr Rotonya , Rader Daniel J , Witschey Walter R 
Published: January 2021

Abstract

Objective
The objective was to develop a fully automated algorithm for abdominal fat segmentation and to deploy this method at scale in an academic biobank.

Materials and Methods
We built a fully automated image curation and labeling technique using deep learning and distributive computing to identify subcutaneous and visceral abdominal fat compartments from 52,844 computed tomography scans in 13,502 patients in the Penn Medicine Biobank (PMBB). A classification network identified the inferior and superior borders of the abdomen, and a segmentation network differentiated visceral and subcutaneous fat. Following technical evaluation of our method, we conducted studies to validate known relationships with visceral and subcutaneous fat.

Results
When compared with 100 manually annotated cases, the classification network was on average within one 5-mm slice for both the superior (0.4 ± 1.1 slice) and inferior (0.4 ± 0.6 slice) borders. The segmentation network also demonstrated excellent performance with intraclass correlation coefficients of 1.00 (P &lt; 2 × 10-16) for subcutaneous and 1.00 (P &lt; 2 × 10-16) for visceral fat on 100 testing cases. We performed integrative analyses of abdominal fat with the phenome extracted from the electronic health record and found highly significant associations with diabetes mellitus, hypertension, and renal failure, among other phenotypes.

Conclusions
This work presents a fully automated and highly accurate method for the quantification of abdominal fat that can be applied to routine clinical imaging studies to fuel translational scientific discovery.
Genome-wide analysis of chromatin structure changes upon MyoD binding in proliferative myoblasts during the cell cycle
Authors: Wu Qianmei , Fujii Takeru , Harada Akihito , Tomimatsu Kosuke , Miyawaki-Kuwakado Atsuko , Fujita Masatoshi , Maehara Kazumitsu , Ohkawa Yasuyuki 
Published: January 2021

Abstract
MyoD, a myogenic differentiation protein, has been studied for its critical role in skeletal muscle differentiation. MyoD-expressing myoblasts have a potency to be differentiated with proliferation of ectopic cells. However, little is known about the effect on chromatin structure of MyoD binding in proliferative myoblasts. In this study, we evaluated the chromatin structure around MyoD-bound genome regions during the cell cycle by chromatin immunoprecipitation sequencing. Genome-wide analysis of histone modifications was performed in proliferative mouse C2C12 myoblasts during three phases (G1, S, G2/M) of the cell cycle. We found that MyoD-bound genome regions had elevated levels of active histone modifications, such as H3K4me1/2/3 and H3K27ac, compared with MyoD-unbound genome regions during the cell cycle. We also demonstrated that the elevated H3K4me2/3 modification level was maintained during the cell cycle, whereas the H3K27ac and H3K4me1 modification levels decreased to the same level as MyoD-unbound genome regions during the later phases. Immunoblot analysis revealed that MyoD abundance was high in the G1 phase then decreased in the S and G2/M phases. Our results suggest that MyoD binding formed selective epigenetic memories with H3K4me2/3 during the cell cycle in addition to myogenic gene induction via active chromatin formation coupled with transcription.
Reproductive Strategies That May Facilitate Invasion Success: Evidence From a Spider Mite
Authors: Zhou Peng , He Xiong Zhao , Chen Chen , Wang Qiao 
Published: January 2021

AbstractWith significant surge of international trade in recent decades, increasingly more arthropod species have become established outside their natural range of distribution, causing enormous damage in their novel habitats. However, whether a species can colonize its new environment depends on its ability to overcome various barriers which may result in establishment failure, such as inbreeding depression and difficulty to find mates. Here, we used a haplodiploid pest, Tetranychus ludeni Zacher (Acari: Tetranychidae), which is native to Europe but now cosmopolitan, to investigate whether its reproductive strategies have facilitated its invasion success, providing knowledge to develop programs for prediction and management of biological invasions. We show that inbreeding had no negative influence on female reproductive outputs and longevity over 11 successive generations, allowing mother-son and brother-sister mating to occur at the invasion front without adverse consequences in fitness. Virgin females produced maximum number of sons in their early life to ensure subsequent mother-son mating but later saved resources to prolong longevity for potential future mating. Females maximized their resource allocation to egg production immediately after mating to secure production of maximum number of both daughters and sons as early as possible. Furthermore, mated females with mating delay increased proportion of daughters in offspring produced to compensate the loss of production of daughters during their virgin life. We suggest that the lack of inbreeding depression in successive generations and the ability to adjust resource allocations depending whether and when mating occurs may be the key features that have facilitated its invasion success.