bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photoconductive emitters for pulsed terahertz generation
Authors: Bacon David R , Madéo Julien , Dani Keshav M 
Published: April 2021

Abstract
Conceived over 30 years ago, photoconductive (PC) emitters have proved essential in the development and spread of terahertz technology. Since then, not only have they been used extensively in a wide range of spectroscopic and imaging applications, they have also undergone significant improvements in performance, leading to their use for broadband or non-linear spectroscopy. In this review article, we provide an overview of the literature, highlighting the key milestones in the progression of the PC emitter. We also investigate the future of PC technology and review the existing challenges.
P38 COVID-19 impact on Surgical Training And Recovery Planning (COVID-STAR) Survey
Authors:   COVID-STAR collaborative research group
Published: April 2021

Abstract

Background
The COVID-19 pandemic has resulted in dynamic changes to healthcare delivery. Surgery as a specialty has been significantly affected and with that the delivery of surgical training.

Method
This national, collaborative, cross sectional study comprising 13 surgical trainee associations distributed a pan surgical specialty survey on the COVID-19 impact on surgical training over a 4-week period (11th May - 8th June 2020). The survey was voluntary and open to medical students and surgical trainees of all specialties and training grades. All aspects of training were qualitatively assessed. This study was reported according to STROBE guidelines.

Results
810 completed responses were analysed. (M401: F 390) with representation from all deaneries and training grades. 41% of respondents (n = 301) were redeployed with 74% (n = 223) redeployed &gt; 4 weeks. Complete loss of training was reported in elective operating (69.5% n = 474), outpatient activity (67.3%, n = 457), Elective endoscopy (69.5% n = 246) with &gt; 50% reduction in training time reported in emergency operating (48%, n = 326) and completion of work-based assessments (WBA) (46%, n = 309). 81% (n = 551) reported course cancellations and departmental and regional teaching programmes were cancelled without rescheduling in 58% and 60% of cases respectively. A perceived lack of Elective operative exposure and completions of WBA’s were the primary reported factor affecting potential training progression. Overall, &gt; 50% of trainees (n = 377) felt they would not meet the competencies required for that training period.

Conclusion
This study has demonstrated a perceived negative impact on numerous aspects of surgical training affecting all training specialties and grades.
INCIPIENT GENOME DIFFERENTIATION IN GOSSYPIUM. I. CHROMOSOMES 14, 15, 16, 19 AND 20 ASSESSED IN G. HIRSUTUM, G. RAIMONDII AND G. LOBATUM BY MEANS OF SEVEN A-D TRANSLOCATIONS
Authors: Menzel Margaret Y , Brown Meta S , Naqi Safia 
Published: April 2021

ABSTRACT
The genus Gossypium is favorable for study of genome divergence at several levels. Early stages of divergence have been studied among four D genomes by comparing chiasma frequencies (reciprocal exchanges) between pairs of genomes and between individual counterpart chromosomes marked by heterozygous translocations. D5 (G. raimondii) shows barely detectable differentiation from from Dh (G. hirsutum), whereas D7 (G. lobatum) is considerably less closely related to Dh than is D5. Fragmentary data suggest that D2-2 (G. harknessii) falls between D5 and D7 in its relationship to Dh. Since chiasma frequencies in individual chromosomes and marked regions exhibit the same order of relationships as their corresponding whole genomes, it is concluded that the genome differentiation is generalized (i.e., nucleus-wide) rather than localized in specific chromosomes or chromosome regions. Estimates of relationships based on reciprocal exchange frequencies agree with those based upon preferential synapsis in allohexaploids reported previously. Since preferential synapsis and reciprocal exchange frequencies reveal the same order of relationships, it is concluded that to some extent they reflect common underlying changes in chromosome properties, despite recent evidence that synapsis and crossing over are under independent genetic control.
THE CONSTRUCTION OF RING CHROMOSOMES OF AUTOSOMAL HETEROCHROMATIN IN DROSOPHILA MELANOGASTER
Authors: Hilliker Arthur J 
Published: April 2021

ABSTRACT
The synthesis of ring chromosomes consisting entirely of Drosophila autosomal heterochromatin is described. Our ability to obtain these heterochromatic ring chromosomes from irradiated oocytes is a logical prediction of and constitutes, therefore, a further proof for the translocation model of the origin of compound chromosomes. Additionally, the synthesis of these chromosomes provides us with potentially useful probes for the analysis of the function(s) of Drosophila heterochromatin.
THE NATURE OF GENETIC RECOMBINATION NEAR THE THIRD CHROMOSOME CENTROMERE OF DROSOPHILA MELANOGASTER
Authors: Denell R E , Keppy D O 
Published: April 2021

ABSTRACT
Previous studies have indicated that recombination near the third chromosome centromere is associated with negative chromosome interference, a phenomenon for which GREEN (1975) and SINCLAIR (1975) suggested gene conversion as a possible mechanism. In this report, we demonstrate that negative chromosome interference is still observed when deficiencies or translocation breakpoints are scored as the middle markers in recombination experiments and the rate of recombination is increased by interchromosomal effect. We argue that these chromosomal rearrangement breakpoints are not subject to conversion. Since neither successive premeiotic and meiotic exchanges, nor negative chromatid interference, can by themselves account for the negative chromosome interference, we conclude that a greater than expected frequency of multiple exchanges actually occurs. We further suggest that negative chromosome interference may be characteristic of all chromosomal regions normally showing very little exchange in relation to physical length.
POPULATION GENETICS OF DROSOPHILA NASUTA NASUTA, DROSOPHILA NASUTA ALBOMICANA AND THEIR HYBRIDS. I. KARYOTYPIC MOSAICISM IN THE HYBRID POPULATIONS
Authors: Rajasekarasetty M R , Gowda L Siddaveere , Krishnamurthy N B , Ranganath H A 
Published: April 2021

ABSTRACT
D. n. nasuta and D. n. albomicana constitute a pair of chromosomal races with 2n=8 and 2n=6, respectively. The F1 of these has 2n=7 and it is fertile. There exists a state of karyotypic mosaicism as evidenced by the presence of 26 types of chromosome combinations in F2, F3, and F10 populations. In the midst of this karyotypic noise, the karyotype similar to that of F1 reached 51% of the population. Implications of these findings are discussed.
NEW PROPERTIES OF THE TWO-LOCUS PARTIAL SELFING MODEL WITH SELECTION
Authors: Holden L R 
Published: April 2021

ABSTRACT
Analytic solutions are obtained for the equilibria of a simple two-locus, heterotic selection model with mixed selfing and random outcrossing. T W O general phenomena are possible, depending upon the viabilities and the degree of selfing: (1) Negative disequilibrium potential, under which only gametic disequilibrium is possible; and (2) positive disequilibrium potential, which can result in permanent gametic disequilibrium provided that linkage is sufficiently tight. Under random mating (s = O), these two situations correspond to negative and positive additive epistasis, respectively. With partial self-fertilization, however, this is no longer true, and a more appropriate measure of gametc dis-equilibrium potential, ∆ (s), is introduced. A numerically aided examination of the model results in the discovery of two new properties of partial selfing with selection: (1) With negative disequilibrium potential (∆(s) &lt; 0), the equilibrium mean fitness increases with increasing recombination. With positive disequilibrium potential (∆(s) &gt; 0), the opposite is true. (2) Gametic disequilibrium can increase or decrease as the degree of selfing is increased. Therefore, it is apparent that partial selfing and linkage are not analogous as regards the maintenance of disequilibrium.
THE RATE OF ALLELISM OF LETHAL GENES IN A GEOGRAPHICALLY STRUCTURED POPULATION
Authors: Yokoyama Shozo 
Published: April 2021

ABSTRACT
The expected rate of allelism, E[I(x)], of lethal genes between two colonies with distance x in a structured population is studied by using one-and two-dimensional stepping-stone models. It is shown that E[I(x)] depends on the magnitude of selection in heterozygous condition (h), the rate of migration among adjacent colonies (m), the number of loci which produce lethal mutations (n) and the effective population size of each colony (N).——E[I(x)] always decreases with distance x. The rate of decrease is affected strongly by the magnitude of m. The rate of decrease is faster when m is small. E[I(x)] also decreases with increasing N and n. The effect of h on E[I(x)] is somewhat complicated. However, E[I(O)] is always smaller when h is small than when it is large.——For large x, the following approximate formulae may be obtained: where and Var (q) are the mean and the-variance of gene frequencies in each colony, t is approximated as t = h, 2√u; —h for the partially recessive, completely recessive, and overdominant lethals, respectively, and C O is a function of m and t. It is clear that E[I(x)] declines exponentially with x in a one-dimensional habitat. The decrease E[I(x)] is faster in a two-dimensional habitat than in a one-dimensional habitat. The present result is applied to some of the existing data and the estimation of population parameters is also discussed.
POLYMORPHISM OF THE HEREDITARY SIGMA VIRUS IN NATURAL POPULATIONS OF DROSOPHILA MELANOGASTER
Authors: Fleuriet Annie 
Published: April 2021

ABSTRACT
Previous studies have shown that, in natural French populations of Drosophila melanogaster, 10 to 20% of the flies are infected by the noncontagious, hereditary rhabdovirus sigma responsible for CO2 sensitivity. These populations are also polymorphic for two alleles [ref(2)Po and ref(2)Pp of a gene for resistance to the sigma virus. Evidence is given here that two viral genetic types, differing in their response to the ref(2)Pp allele, are present in these populations of flies; the most common type is only slightly sensitive to the ref(2)Pp allele.
DEVIATIONS OF GENOTYPIC STRUCTURES FROM HARDY-WEINBERG PROPORTIONS UNDER RANDOM MATING AND DIFFERENTIAL SELECTION BETWEEN THE SEXES
Authors: Ziehe Martin , Gregorius Hans-Rolf 
Published: April 2021

ABSTRACT
Population genetic models, such as differential viability selection between the sexes and differential multiplicative fecundity contributions of the sexes, are considered for a single multiallelic locus. These selection models usually produce deviations of the zygotic genotype frequencies from Hardy-Weinberg proportions. The deviations are investigated (with special emphasis put on equilibrium states) to quantify the effect of selective asymmetry in the two sexes. For many selection regimes, the present results demonstrate a strong affinity of zygotic genotype frequencies for Hardy-Weinberg proportions after two generations, at the latest. It is shown that the deviations of genotypic equilibria from the corresponding Hardy-Weinberg proportions can be expressed and estimated by means of selection components of only that sex with the lower selection intensity. This corresponds to the well-known fact that viability selection acting in only one sex yields Hardy-Weinberg equilibria.
NUCLEOCYTOPLASMIC RELATIONS IN A MUTATOR-SUPPRESSOR SYSTEM OF DROSOPHILA ANANASSAE
Authors: Hinton Claude W 
Published: April 2021

ABSTRACT
A partially characterized mutator-suppressor system, previously identified in the ca; stw stock of Drosophila ananassae, was shown to exist in the ca ancestral stock; it consists of a clastogenic mutator of sperm chromosomes and a supressor that functions in the oöcyte soon after fertilization. Transmission of these components was monitored by Minute mutation frequencies produced by the progeny of recurrently backcrossed hybrid females derived from reciprocal outcrosses of the ca stock. In this way, the mutator was shown to be an extrachromosomally transmitted element whose propagation depends upon nuclear genes. Suppressivity was found to be determined by nuclear genes, some of which are expressed only after a delay of several generations. Neither the mutator nor its suppressor appear to be infectious. Measurement of dominant lethal frequencies showed that the suppressor is completely effective in repair of premutational lesions induced by the mutator. The properties of this mutator-suppressor system were compared with those of hybrid dysgenesis in Drosophila melanogaster.
Effects of 2-D random velocity perturbations on 2-DSHshort-period ground motion simulations in the basin of Nice, France
Authors: Tchawe F N , Gelis C , BONILLA L F , Lopez-Caballero F 
Published: April 2021

SUMMARYSome geological configurations, like sedimentary basins, are prone to site effects. Basins are often composed of different geological layers whose properties are generally considered as spatially homogeneous or smoothly varying. In this study, we address the influence of small-scale velocity fluctuations on seismic response. For this purpose, we use the spectral element method to model the 2-D SH wave propagation on a basin of 1.1 km long and ≈ 60 m deep, representing a 2-D profile in the city of Nice, France. The velocity fluctuations are modelled statistically as a random process characterized by a Von Karman autocorrelation function and are superimposed to the deterministic model. We assess the influence of the amplitude and correlation length of the random velocities on the surface ground motion. We vary the autocorrelation function’s parameters and compute seismic wavefields in 10 random realizations of the stochastic models. The analyses of our results focus on the envelope and phase differences between the waveforms computed in the random and deterministic models; on the variability of ground motion intensity measures, such as the peak ground velocity, the pseudo-spectral acceleration response; and the 2-D basin response (transfer function). We find that the amplitude of fluctuations has a greater effect on the ground motion variability than the correlation length. Depending on the random medium realization, the ground motion in one stochastic model can be locally amplified or deamplified with respect to the reference model due to the presence of high or low velocity contrasts, respectively. When computing the mean amplification of different random realizations, the results may be smaller than those of the reference media due to the smoothing effect of the average. This study highlights the importance of knowing the site properties at different scales, particularly at small scales, for proper seismic hazard assessment.
Isotropic and azimuthally anisotropic Rayleigh wave dispersion across the Juan de Fuca and Gorda plates and U.S. Cascadia from earthquake data and ambient noise two- and three-station interferometry
Authors: Zhang Shane , Wang Hongda , Wu Mengyu , Ritzwoller Michael H 
Published: April 2021

SUMMARY
We use data from the Cascadia Initiative (CI) amphibious array and the USArray Transportable Array to construct and compare Rayleigh wave isotropic and azimuthally anisotropic phase speed maps across the Juan de Fuca and Gorda Plates extending onto the continental northwestern United States. Results from both earthquakes (28–80 s) as well as ambient noise two- and three-station interferometry (10–40 s) are produced. Compared with two-station interferometry, three-station direct wave interferometry provides &gt;50 per cent improvement in the signal-to-noise ratio and the number of dispersion measurements obtained, particularly in the noisier oceanic environment. Earthquake and ambient noise results are complementary in bandwidth and azimuthal coverage, and agree within about twice the estimated uncertainties of each method. We, therefore, combine measurements from the different methods to produce composite results that provide an improved data set in accuracy, resolution and spatial and azimuthal coverage over each individual method. A great variety of both isotropic and azimuthally anisotropic structures are resolved. Across the oceanic plate, fast directions of anisotropy with 180° periodicity (2ψ) generally align with palaeo-spreading directions while 2ψ amplitudes mostly increase with lithospheric age, both displaying substantial variations with depth and age. Strong (&gt;3 per cent) apparent anisotropy with 360° periodicity (1ψ) is observed at long periods (&gt;50 s) surrounding the Cascade Range, probably caused by backscattering from heterogeneous isotropic structures.
Challenging the association between health literacy and health: the role of conversion factors
Authors: Rüegg René , Abel Thomas 
Published: April 2021

SummaryPrevious studies have found substantial correlations between health literacy and various health outcomes. However, the role of social and personal factors in those links remains understudied. Applying a moderation approach, we assume that these factors function as conversion factors on the associations between health literacy and health outcomes. Consequently, we test if associations between health literacy and health outcomes are stronger among young male adults who score high in conversion factors compared to those who score low. Cross-sectional data from the Young Adult Survey Switzerland were used for the analyses (n = 9339, age = 18−25). Multiple logistic regression analyses were applied to estimate associations between health literacy and health. Moderator analyses with three conversion factors and five health outcomes were conducted. For each health outcome at least one conversion factor moderated the association between health literacy and health according to the hypothesis. Although strength and form of the moderation effect differ across analyses, generally stronger associations were found among groups with beneficial social or personal factors. The present findings support the hypothesis that conversion factors play a crucial role in the associations between health literacy and health. The findings, thus, point towards a potential risk of linear health literacy approaches that assume equal benefits from increased health literacy. Individuals with beneficial social and personal factors (those already privileged) may enjoy greater health benefits from interventions improving health literacy.
Outcome analysis of a conservative approach to diaphragmatic paralysis following congenital cardiac surgery in neonates and infants: a bicentric retrospective study
Authors: Denamur Sophie , Chenouard Alexis , Lefort Bruno , Baron Olivier , Neville Paul , Baruteau Alban , Joram Nicolas , Chantreuil Julie , Bourgoin Pierre 
Published: April 2021

Abstract

OBJECTIVES
Diaphragmatic paralysis following congenital cardiac surgery is associated with significant morbidity and mortality. Spontaneous recovery of diaphragmatic function has been described, contrasting with centres providing early diaphragmatic plication. We aimed to describe the outcomes of a conservative approach, as well as to identify factors associated with a failure of the strategy.

METHODS
This is a retrospective study of patients admitted after cardiac surgery and suffering unilateral diaphragmatic paralysis within 2 French Paediatric Cardiac Surgery Centers. The conservative approach, defined by the prolonged use of ventilation until successful weaning from respiratory support, was the primary strategy adopted in both centres. In case of unsuccessful evolution, a diaphragmatic plication was scheduled. Total ventilation time included invasive and non-invasive ventilation. Diaphragm asymmetry was defined by the number of posterior rib segments counted between the 2 hemi-diaphragms on the chest X-ray after cardiac surgery.

RESULTS
Fifty-one neonates and infants were included in the analysis. Patients’ median age was 12.0 days at cardiac surgery (5.0–82.0), and median weight was 3.5 kg (2.8–4.9). The conservative approach was successful for 32/51 patients (63%), whereas 19/51 patients (37%) needed diaphragm plication. There was no difference in patients’ characteristics between groups. Respiratory support prolonged for 21 days or more and diaphragm asymmetry more than 2 rib segments were independently associated with the failure of the conservative strategy [odds ratio (OR) 6.9 (1.29–37.3); P = 0.024 and OR 6.0 (1.4–24.7); P = 0.013, respectively].

CONCLUSIONS
The conservative approach was successful for 63% of the patients. We identified risk factors associated with the strategy’s failure.
Plasmodium malariae and Plasmodium falciparum comparative susceptibility to antimalarial drugs in Mali
Authors: Dembele Laurent , Aniweh Yaw , Diallo Nouhoum , Sogore Fanta , Sangare Cheick Papa Oumar , Haidara Aboubecrin Sedhigh , Traore Aliou , Diakité Seidina A S , Diakite Mahamadou , Campo Brice , Awandare Gordon A , Djimde Abdoulaye A 
Published: April 2021

Abstract

Objectives
To evaluate Plasmodium malariae susceptibility to current and lead candidate antimalarial drugs.

Methods
We conducted cross-sectional screening and detection of all Plasmodium species malaria cases, which were nested within a longitudinal prospective study, and an ex vivo assessment of efficacy of a panel of antimalarials against P. malariae and Plasmodium falciparum, both PCR-confirmed mono-infections. Reference compounds tested included chloroquine, lumefantrine, artemether and piperaquine, while candidate antimalarials included the imidazolopiperazine GNF179, a close analogue of KAF156, and the Plasmodium phosphatidylinositol-4-OH kinase (PI4K)-specific inhibitor KDU691.

Results
We report a high frequency (3%–15%) of P. malariae infections with a significant reduction in ex vivo susceptibility to chloroquine, lumefantrine and artemether, which are the current frontline drugs against P. malariae infections. Unlike these compounds, potent inhibition of P. malariae and P. falciparum was observed with piperaquine exposure. Furthermore, we evaluated advanced lead antimalarial compounds. In this regard, we identified strong inhibition of P. malariae using GNF179, a close analogue of KAF156 imidazolopiperazines, which is a novel class of antimalarial drug currently in clinical Phase IIb testing. Finally, in addition to GNF179, we demonstrated that the Plasmodium PI4K-specific inhibitor KDU691 is highly inhibitory against P. malariae and P. falciparum.

Conclusions
Our data indicated that chloroquine, lumefantrine and artemether may not be suitable for the treatment of P. malariae infections and the potential of piperaquine, as well as new antimalarials imidazolopiperazines and PI4K-specific inhibitor, for P. malariae cure.
Association between limiting the number of open records in a tele-critical care setting and retract–reorder errors
Authors: Udeh Chiedozie , Canfield Christina , Briskin Isaac , Hamilton Aaron C 
Published: April 2021

AbstractBackgroundWrong patient selection errors may be tracked by retract–reorder (RAR) events. The aim of this quality improvement study was to assess the impact of reducing the number of concurrently open electronic health records from 4 to 2 on RAR errors generated by a tele-critical care service.MethodsThe study encompassed 32 months before and 21 months after restriction. Chi-Square test of proportions and T statistical process control chart for rare events were used.ResultsThere were 156 318 orders with 57 RAR errors (36.5/100 000 orders) before restriction, and 122 587 orders with 34 errors (27.7/100 000 orders) after. Rates were not statistically different (P = .20), but analysis was underpowered. When plotted on a T control chart, random variation was detected between RAR errors.ConclusionWe found no significant difference in RAR errors in the tele-critical care setting after open record limitation. Other strategies should be studied to reduce wrong patient selection errors.