bluuebunny/crossref_metadata_2025 huggingface dataset:
Over time variation in microsatellite patterns in a natural wild potato population from northwest Argentina
Authors: Leofanti Gabriela Agustina , Camadro Elsa Lucila , Erazzú Luis Ernesto
Published: February 2021

The common potato, Solanum tuberosum L. (2n = 4x = 48), has 100–200 related wild taxonomic species endemic to the Americas, which constitute invaluable sources of genetic diversity. They form a polyploid series with 2n = 2x – 6x (x = 12) and can reproduce asexually by tubers and stolons and/or sexually by seeds. Information is scarce on their preponderant mode of reproduction and its consequences on the genetic population structure over time. In previous work, a morphologically variable wild potato population from northwestern Argentina was sampled in two consecutive years. Two populations were ex situ regenerated from the sampled propagules (seeds in 2013 and tubers in 2014) for morphological and reproductive studies; these populations exhibited differences in reproductive behavior that could not be related to morphological phenotypes. To ascertain if the observed differences could be related to the captured genetic diversity in each year, a molecular analysis was carried out with seven microsatellite primer pairs located in seven chromosomes of the basic set. The captured genetic diversity, based on the proportion of individuals with a unique pattern of amplified fragments, varied significantly (χ2 α = .05) between sampling years. This could be due to changes in the preponderant mode of reproduction, differential genotype fitness resulting from genotype × environment interactions, or both. Wild potato accessions at germplasm banks are one‐time collection samples; thus, they may not be representative of the genetic diversity of the sampled population. To properly ex situ conserve the available genetic diversity, it is advisable to resample the sites whenever possible and to conform each accession with the successive samples.
Managing propagule pressure to prevent invasive species establishments: propagule size, number, and risk–release curve
Authors: Stringham Oliver C. , Lockwood Julie L.
Published: February 2021

There is considerable evidence that keeping propagule pressure low can drastically reduce establishment probability of potential invasive species. Yet, most management plans and research efforts fail to explicitly acknowledge all three of the components of propagule pressure: size, number, and the risk–release relationship. It is unclear how failing to specify one or more of these components can influence the efficacy of management plans in preventing invasive species establishment. Furthermore, even if all components are acknowledged and quantified, there currently is no mathematical tool available to calculate the levels of propagule pressure that ensure attainment of a predetermined, and system‐specific, target establishment probability. Here, we quantify the resulting uncertainty in establishment probability when one or more components of propagule pressure is unknown by using parameter uncertainty analysis on realistic values of propagule pressure. In addition, to aid in the development of management plans that explicitly set propagule pressure limits, we develop a propagule‐pressure sensitivity analysis that we use to determine the required reduction in levels for propagule size and number (representative of management actions) to maintain a target establishment probability. We show that the precision of establishment estimates is highly dependent on knowledge of all three propagule pressure components, where the possible range of values for establishment probability can vary by over 50% without full specification. In addition, our sensitivity analysis showed that propagule size and number can be altered independently or in conjunction to lower establishment probability below a target level. Importantly, our sensitivity analysis was able to specifically quantify how much reduction in a propagule pressure component(s) is needed to reach a given target establishment probability. Our findings suggest that quantifying the three components of propagule pressure should be a priority for invasive species prevention moving forward. Furthermore, our sensitivity analysis tool can serve to guide the development of new invasive species management plans in a transparent and quantitative manner. Together with information on the costs associated with approaches to reducing propagule pressure, our tool can be used to identify the most cost‐effective approach to prevent invasive species establishments.
The applicability of eDNA metabarcoding approaches for sessile benthic surveying in the Kimberley region, north‐western Australia
Authors: West Katrina M. , Adam Arne A. S. , White Nicole , Robbins William D. , Barrow Daniel , Lane Adrian , T. Richards Zoe
Published: February 2021

The application of environmental DNA technologies is a promising new approach to rapidly audit biodiversity across large‐scale, remote regions. Here, we examine the efficacy of a dual‐assay eDNA metabarcoding approach for sessile benthic bioassessments in the turbid waters of the Lalang‐garram marine parks, Kimberley, north‐western Australia. We ask three principal questions: (1) “Is the eDNA released by sessile benthic taxa (i.e., hard and soft corals, sponges and tunicates) locally detectable?”, (2) “What level of taxonomic resolution is afforded by eDNA metabarcoding using the ITS2 region?”, and (3) “How well does eDNA metabarcoding compare to conventional benthic survey techniques?”. We report that a dual‐assay eDNA metabarcoding approach can detect approximately 70% of the local benthic taxa (i.e., at a species, genus level). It is, however, not as effective at the individual/population level, detecting only approximately 40% of unique amplicon sequence variant (ASV) signals released by an array of individual benthic organisms at the surveyed locations. In examining the efficacy and resolution of the applied ITS2 metabarcoding markers for bioassessments, we report large gaps in the variety of publicly available benthic ITS2 reference sequence data, limiting our ability to provide robust taxonomic assignments. These findings highlight the need to extend ITS2 databases for greater regional representation. Until this is adequately addressed, we recommend that investigating taxonomic assignments to a genus level is the most robust approach for benthic monitoring using eDNA. Lastly, we found eDNA metabarcoding and conventional belt transect surveys each detected numerous unique hard coral genera, indicating that a combined approach provides the most effective way to audit benthic biodiversity. This point notwithstanding, eDNA metabarcoding had the power to distinguish similar diversity trends between sites to that determined by the belt transect methodology, validating the application of eDNA metabarcoding as either a stand‐alone, or complementary technique for assessing sessile benthic taxa.
Diagnostic Performance of Transient Elastography in Biliary Atresia Among Infants With Cholestasis
Authors: Boo Yin-Ann , Chang Mei-Hwei , Jeng Yung-Ming , Peng Shinn-Forng , Hsu Wen-Ming , Lin Wen-Hsi , Chen Huey-Ling , Ni Yen-Hsuan , Hsu Hong-Yuan , Wu Jia-Feng
Published: February 2021

Biliary atresia (BA) is a challenging liver disease in infancy. Early diagnosis of BA is important for timely hepatoportoenterostomy. We evaluated the age-specific diagnostic performance of transient elastography (TE) with a liver stiffness measurement (LSM) greater than 7.7 kPa in BA among infants with cholestasis. A total of 61 infants with cholestasis (5-121 days of age) were enrolled in this prospective follow-up study; 15 infants were BA. Four age groups were defined (≤30, 31-60, 61-90, and 91-180 days). Picrosirius red staining was performed to quantify the percentage of collagen fibers in liver specimens. The utility of an LSM greater than 7.7 kPa for diagnosis of BA among infants with cholestasis was compared among age groups. In all four groups, TE showed high diagnostic power for BA using the criterion of an LSM greater than 7.7 kPa. Positive predictive values were 100%, 100%, and 100% in the groups aged 30 days or younger, 31 to 60 days, and 61 to 90 days, respectively. Respective negative predictive values were 90.9%, 94.7%, and 100%, and respective diagnostic accuracies were 92.9%, 95.2%, and 100%. The positive predictive value, negative predictive value, and diagnostic accuracy were 100%, 100%, and 100%, respectively, for LSM greater than 8.8 kPa in the group aged 91 to 180 days. The LSM was positively correlated with the percentage of collagen fibers stained by picrosirius red (P = 0.03). Conclusion: In this prospective follow-up study, TE had good diagnostic accuracy for differentiation of BA from non-BA cholestasis in infants with cholestasis who were 90 days of age or younger. The LSM was significantly positive correlated with the liver fibrosis status stained by picrosirius red in infants with cholestasis.
Sex differences in hippocampal connectivity during spatial long‐term memory
Authors: Spets Dylan S. , Fritch Haley A. , Slotnick Scott D.
Published: February 2021

Sex differences in brain activity have been reported across various types of long‐term memory. To our knowledge, sex differences in functional connectivity during long‐term memory have not been investigated. A previous study on the structural connectome identified that female brains have a greater degree of interhemispheric connectivity than males, whereas males have a greater degree of intrahemispheric connectivity than females. The aim of the current investigation was twofold: (a) identify which brain regions were functionally connected to the hippocampus during spatial long‐term memory, and (b) determine if there were sex differences in the functionally connected regions. During the study phase, abstract shapes were presented to the left or right of fixation. During the test phase, abstract shapes were presented at fixation and participants classified each item as previously on the “left” or “right”. A hippocampal region of interest (ROI) was identified by contrasting spatial memory hits and misses. The peak coordinate from this ROI was used to define the center of a sphere that was used as the seed for the functional connectivity analysis. The connectivity analysis produced many connected activations including the medial posterior frontal cortex, lateral posterior frontal cortex, left inferior frontal gyrus, posterior cingulate cortex, and caudate/putamen. Although there were no regions with greater connectivity in females than males, the male versus female comparison produced connected activations in the medial posterior frontal cortex, anterior prefrontal cortex, precuneus, and cingulate sulcus. Females also had greater interhemispheric connectivity than males. The current findings suggest collapsing across sex in cognitive neuroscience studies may not be warranted.
The Interplay Between the Immune System, the Renin‐Angiotensin‐Aldosterone System (RAAS), and RAAS Inhibitors May Modulate the Outcome of COVID‐19: A Systematic Review
Authors: Naveed Hiba , Elshafeey Abdallah , Al‐Ali Dana , Janjua Emmad , Nauman Areej , Kawas Hussam , Kaul Ridhima , Saed Aldien Arwa , Elshazly Mohamed B. , Zakaria Dalia
Published: February 2021

Since the discovery of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), numerous research has been undertaken to delineate the various effects of the virus which manifests in many ways all over the body. The association between the SARS‐CoV‐2 invasion mechanism and the renin‐angiotensin‐aldosterone system (RAAS) receptors, created many debates about the possible consequences of using RAAS‐modulating drugs including angiotensin‐converting enzyme inhibitors (ACEi) and angiotensin II receptor blockers (ARBs) during the pandemic. Many clinical studies were conducted to assess the outcomes of coronavirus disease 2019 (COVID‐19) in patients who use ACEi/ARBs following the arguments claiming to discontinue these drugs as a precautionary measure. Although several studies mainly analyzed the outcomes of the disease, this review aimed to compare specific blood markers in both groups of COVID‐19 patients to gain better insight into the interaction of ACEi/ARBs with different body functions during the infection. Several databases were searched using a combination of keywords followed by screening and data extraction. Only 28 studies met our inclusion criteria, the majority of which showed no significant difference between the inflammation markers of COVID‐19 patients who used or did not use ACEi/ARBs. Interestingly, 6 studies reported lower inflammatory markers in COVID‐19 patients who used ACEi/ARBs, and 6 studies reported better outcomes among the same group. We therefore concluded that the use of ACEi/ARBs may not lead to worse prognosis of COVID‐19 and may even play a protective role against the hyperinflammatory response associated with COVID‐19.
Subjective assessment on visual fatigue versus stereoscopic disparities
Authors: Liu Yi , Guo Xiang , Fan Yubo , Meng Xiangfeng , Wang Jiahui
Published: February 2021

The sense of discomfort when watching stereoscopic display caused by visual fatigue has hindered the widespread applications of stereoscopic display. In this work, we explore the relationship between visual fatigue and stereoscopic parallax using subjective assessment. The visual fatigue of the subjects is evaluated after viewing different parallax stereoscopic samples. It shows that visual fatigue exacerbates greater in negative parallax than positive parallax. Surprisingly, the results indicate that visual fatigue can be alleviated with tiny parallax, which increases the comfort of stereoscopic visual perception. We envision that this relationship is able to provide helpful hints in designing visual healthy stereoscopic images.
A Call for More Nuanced Dialogues About Trophy Hunting
Authors: Mitchell Carl D. , Bleich Vernon C. , Bowyer R. Terry , Heffelfinger James R. , Stewart Kelley M. , White Paula A.
Published: February 2021

Reported effects of trophy harvest often are controversial. The subject is nuanced and many studies lack details necessary to place their results in context. Consequently, many studies are misunderstood or their conclusions misapplied. We propose that all dialogues about trophy hunting include a definition of how they use the term trophy, details of variables measured and why they were selected, and explanations of temporal and spatial scales employed. Only with these details can potential effects of trophy hunting be understood in context and used for management and policy decisions. © 2021 The Wildlife Society.
Global dynamics for a class of inhomogeneous nonlinear Schrödinger equations with potential
Authors: Dinh Van Duong
Published: February 2021

We consider a class of L2‐supercritical inhomogeneous nonlinear Schrödinger equations with potential in three dimensions. In the focusing case, using a recent method of Dodson and Murphy, we first study the energy scattering below the ground state for the equation with radially symmetric initial data. We then establish blow‐up criteria for non‐radial solutions to the equation. In the defocusing case, we also prove the energy scattering for the equation with radially symmetric initial data.
Species Differences in in vitro and Estimated in vivo Kinetics for Intestinal Microbiota Mediated Metabolism of Acetyl‐deoxynivalenols
Authors: Jin Jing , Spenkelink Albertus , Beekmann Karsten , Baccaro Marta , Xing Fuguo , Rietjens Ivonne M. C. M.
Published: February 2021

Scope

Deoxynivalenol (DON) and its acetylated derivatives 3‐acetyl‐DON (3‐Ac‐DON) and 15‐acetyl‐DON (15‐Ac‐DON) are important mycotoxins of concern in the modern food chain.

Methods and Results

The present study reveals that the rate of de‐acetylation in in vitro anaerobic fecal incubations decreased in the order rat > mouse > human > pig for 3‐Ac‐DON, and mouse > human > rat > pig for 15‐Ac‐DON. The ratio between the de‐acetylation rate of 3‐Ac‐DON and 15‐Ac‐DON varies with the species. Scaling of the kinetic parameters to the in vivo situation results in catalytic efficiencies decreasing in the order human > rat > pig > mouse for 3‐Ac‐DON and human > pig > rat > mouse for 15‐Ac‐DON. The results obtained indicate that in mice, 3‐Ac‐DON can be fully deconjugated while 15‐Ac‐DON cannot. In rats, pigs, and humans, both 3‐Ac‐DON and 15‐Ac‐DON can be totally transformed by gut fecal microbiota during the estimated intestinal residence time. A correlation analysis between the deacetylation rate and the relative abundance of the microbiome suggests Lachnospiraceae may be involved in the deacetylation process.

Conclusion

It is concluded that interspecies differences in deacetylation of acetylated DONs exist but that in risk assessment assumption of complete intestinal deconjugation provides an adequate approach.
Measuring workplace bullying in a U.S. nursing population with the Short Negative Acts Questionnaire
Authors: Anusiewicz Colleen V. , Li Peng , Patrician Patricia A.
Published: February 2021

Efforts to decrease nurse‐reported workplace bullying (WPB) is an interest among researchers, nursing leaders, and healthcare organizations. Varying conceptual definitions and measurement approaches of WPB, however, have created barriers for researchers to provide reliable and consistent information regarding WPB. In this paper, the authors aim to (1) evaluate the reliability and construct validity of the Short Negative Acts Questionnaire (SNAQ) in a sample of U.S. nurses working in hospitals located throughout Alabama, (2) determine targets and non‐targets of WPB, and (3) evaluate the criterion validity of the SNAQ based on WPB classification. The internal consistency reliability and construct validity of the SNAQ in 943 Alabama registered nurses was evaluated using Cronbach's α and confirmatory factor analysis. An exploratory factor analysis was conducted to explore the underlying structure of the SNAQ. Targets and non‐targets of WPB were identified using latent class analysis of the SNAQ and by the self‐labeling item. Agreement between the two methods was evaluated with Cohen's κ. Using both methods, the association between WPB classification and outcomes empirically associated with nurse‐reported WPB was evaluated with random effects multiple logistic regression to determine criterion validity. The results indicate that the SNAQ is a reliable and valid instrument to explore WPB in a sample of U.S. registered nurses working in hospitals throughout Alabama.
Ameliorative effects of total coumarins from the fructus ofCnidium monnieri(L.) Cuss. on 2,4‐dinitrochlorobenzene‐induced atopic dermatitis in rats
Authors: Yu Zhijie , Deng Ting , Wang Ping , Sun Tao , Xu Ying
Published: February 2021

Atopic dermatitis (AD), which is characterized by intense pruritus and serious inflammation, is a chronic skin disease. Modern studies have testified that the total coumarins from the fructus ofCnidiummonnieri(TCFC) possess evident biological activities based on their coumarin compounds. The purpose of this manuscript is to investigate the effects of topical use of TCFC on immune response, inflammation, and skin barrier function in rats with 2,4‐dinitrochlorobenzene (DNCB)‐induced AD. Results indicated that the skin lesion scores of rats were obviously reduced after the management of TCFC, and the spleen and thymus indices also were markedly repressed. TCFC significantly inhibited the overproduction of TNF‐α, interferon‐γ, interleukin (IL)‐4, IL‐13, thymic stromal lymphopoietin, and immunoglobulin E; the epidermal thickness and number of mast cells were notably decreased. The western blot experiment was conducted to determine the effects of TCFC on the mitogen‐activated protein kinases signaling pathway. Results indicated that phosphorylation of extracellular signal‐regulated kinases, p38, and c‐Jun amino‐terminal kinases was significantly blocked by TCFC. In addition, TCFC could upregulate the expression of filaggrin in dorsal skin, which means that TCFC showed a protective effect on skin barrier disruption. Furthermore, TCFC downregulated the levels of IL‐1β, IL‐4, IL‐31, and TSLP mRNA and upregulated the expression of filaggrin mRNA in the dorsal skin of rats. Our research demonstrated the ameliorative effects of TCFC on AD‐like rats by inhibiting immune response and inflammation and recovering skin barrier function.
Angiotensin receptor blockers use and changes in frailty, muscle mass, and function indexes: Singapore Longitudinal Ageing Study
Authors: Ng Tze Pin , Nguyen Tu N. , Gao Qi , Nyunt Ma Shwe Zin , Yap Keng Bee , Wee Shiou‐Liang
Published: February 2021

Background

Pre‐clinical studies suggest that renin–angiotensin system blockade may improve muscle function. Clinical reports of the effect of angiotensin converting enzyme inhibitors (ACEIs) on physical functioning are inconsistent. There are no reports of the effect of angiotensin receptor blockers (ARBs) treatment in older adults.

Methods

We analysed data of 1268 participants in the Singapore Longitudinal Ageing Study (SLAS‐2) who provided information on the use of ACEI, ARB, and other antihypertensive drugs at baseline and follow‐up (mean 4.5 years later). Baseline and follow‐up outcome measures were cumulated deficits frailty index (CD‐FI), physical phenotype frailty index (PP‐FI), calf circumference (CC), knee extension strength, composite muscle mass and strength (MMS) z‐score, and gait speed (GS). In primary analyses, we compared the use and non‐use of an anti‐hypertensive drug class among participants with hypertensive and cardiac disease, and secondarily with participants having other chronic diseases, and those who reported no chronic diseases. Multi‐variable analyses adjusted for socioeconomic status, body mass index ≥30, ≥5 comorbidities, ≥5 drugs use, other non‐ARB or non‐ACEI drugs (calcium channel blockers, beta blockers, or hydrochlorothiazide), MMSE <23, Geriatric Depression Scale score, Nutrition Screening Initiative nutritional risk, physical activities, baseline frailty, and physical performance.

Results

Among study participants, 7.8% (N = 99) were ARB users (62% used losartan), 11.7% (N = 148) were ACEI users (53% used enalapril), and 34.2% (N = 434) were users of other anti‐hypertensive drug classes. The cohort participants overall showed increases in the mean levels and changes in CD‐FI and PP‐FI and decreases in knee extension strength, GS, CC, and MMS. However, among groups, ARB users showed decreasing trends in CD‐FI and increasing trends of CC and MMS. Among participants with hypertensive and cardiovascular disease, there were significant differences in CD‐FI and PP‐FI changes, adjusted for confounding variables: ARB users compared with non‐users showed lesser declines in CD‐FI (0.013 vs. 0.028, P = 0.018) and PP‐FI (0.924 vs. 1.170, P = 0.017). ARB users also showed statistically significantly greater gains in MMS z‐scores: 0.329 vs. 0.076, P = 0.022. There was no association of ACEI or other anti‐hypertensive class use with changes in frailty, MMS, or GS.

Conclusions

The use of ARBs is associated with a reduction in frailty and age‐related loss of muscle mass and strength.
United States' experience in nuchal translucency measurement: variation according to provider characteristics in over five million ultrasound examinations
Authors: Thornburg L. L. , Bromley B. , Dugoff L. , Platt L. D. , Fuchs K. M. , Norton M. E. , McIntosh J. , Toland G. J. , Cuckle H. ,   for the Nuchal Translucency Quality Review Program of the Perinatal Quality Foundation
Published: February 2021

Objective

The Nuchal Translucency Quality Review (NTQR) program has provided standardized education, credentialing and epidemiological monitoring of nuchal translucency (NT) measurements since 2005. Our aim was to review the effect on NT measurement of provider characteristics since the program's inception.

Methods

We evaluated the distribution of NT measurements performed between January 2005 and December 2019, for each of the three primary performance indicators of NT measurement (NT median multiples of the median (MoM), SD of log10 NT MoM and slope of NT with respect to crown–rump length (CRL)) for all providers within the NTQR program with more than 30 paired NT/CRL results. Provider characteristics explored as potential sources of variability included: number of NT ultrasound examinations performed annually (annual scan volume of the provider), duration of participation in the NTQR program, initial credentialing by an alternative pathway, provider type (physician vs sonographer) and number of NT‐credentialed providers within the practice (size of practice). Each of these provider characteristics was evaluated for its effect on NT median MoM and geometric mean of the NT median MoM weighted for the number of ultrasound scans, and multiple regression was performed across all variables to control for potential confounders.

Results

Of 5 216 663 NT measurements from 9340 providers at 3319 sites, the majority (75%) of providers had an NT median MoM within the acceptable range of 0.9–1.1 and 85.5% had NT median MoM not statistically significantly outside this range. Provider characteristics associated with measurement within the expected range of performance included higher volume of NT scans performed annually, practice at a site with larger numbers of other NT‐credentialed providers, longer duration of participation in the NTQR program and alternative initial credentialing pathway.

Conclusions

Annual scan volume, duration of participation in the NTQR program, alternative initial credentialing pathway and number of other NT‐credentialed providers within the practice are all associated with outcome metrics indicating quality of performance. It is critical that providers participate in ongoing quality assessment of NT measurement to maintain consistency and precision. Ongoing assessment programs with continuous feedback and education are necessary to maintain quality care. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.
Molecular diatomic spectroscopy data
Authors: McKemmish Laura K.
Published: February 2021

Accurate and comprehensive diatomic molecular spectroscopic data have long been vital in a wide variety of applications for measuring and monitoring astrophysical, industrial, and other gaseous environments. These data are also used extensively for benchmarking quantum chemistry and applications from quantum computers, ultracold chemistry and the search for physics beyond the standard model. Useful data can be highly detailed like line lists or summative like molecular constants, and obtained from theory, experiment, or a combination. There are plentiful (though not yet sufficient) data available, but these data are often scattered. For example, molecular constants have not been compiled since 1979 despite the existing compilation still being cited more than 200 times annually. Furthermore, the data are interconnected but updates in one type of data are not yet routinely applied to update interconnected data: in particular, new experimental and ab initio data are not routinely unified with other data on the molecule. This paper provides information and strategies to strengthen the connection between data producers (e.g., ab initio electronic structure theorists and experimental spectroscopists), data modelers (e.g., line list creators and others who connect data on one aspect of the molecule to the full energetic and spectroscopic description) and data users (astronomers, chemical physicists, etc.). All major data types are described including their source, use, compilation, and interconnectivity. Explicit advice is provided for theoretical and experimental data producers, data modelers, and data users to facilitate optimal use of new data with appropriate attribution.

This article is categorized under:

Theoretical and Physical Chemistry > Spectroscopy
The Mesolithic Footprints Retained in One Bed of the Former Saltmarshes at Formby Point, Sefton Coast, North West England
Authors: Burns Alison
Published: February 2021

In the early Holocene period, extensive tracts of coastal land were submerged as the climate warmed and meltwaters flooded into the oceans. As the Irish Sea expanded, coastlines altered and large intertidal zones were created as tracts of low-lying land at the tidal margins were gradually submerged. In these areas, reed swamp and saltmarsh formed which, too, were inundated for varying periods of time. However, in the calmer warmer weather of the late spring and summer, birds and mammals were drawn on to the mudflats where they could feed on molluscs, or new reed and sedge shoots, wallow in the cooling mud, drink the brackish water or, for some predators, hunt. The behavioural tendencies of some species are revealed by their footprints which show their engagement within this environment – some breeds moved on to the marshes while others moved away. The humans who shared this landscape understood the opportunities offered by these predictable behaviours. Their trails run along and across those left by many species, leaving a visible network of human and animal activity preserved in the hardened mud. These will be described through an examination of the footprints recorded in three contexts which formed the stratigraphy of a Mesolithic bed at Formby Point in North West England. The persistent return to the mudflats by generations of people reflects an embodied knowledge of this coastal landscape, learnt in childhood and practiced in adulthood. The ability to modify movements in the landscape, to respond to the daily tides, the changing seasons and a fluctuating environment, all suggest a spatial-temporal relationship which not only encompassed a dynamic environment but also the other life that dwelt within it.
Reading Spoor
Authors: Lenssen-Erz Tilman , Pastoors Andreas
Published: February 2021

The spoor of animals and humans alike contain rich information about an individual and about a momentary activity this individual performed. If the – arguably hard-wired – human ability to read spoor and tracks is sufficiently trained, a footprint allows to glean from it various physical, kinetic, medical, social and psychologic data about an individual, as has been observed among various populations across the globe. The Ju|’hoansi San from northern Namibia still today practice traditional hunting so that tracking is a skill that is required and trained on a daily base. For a good tracker, the information she or he gets from spoor is equally rich on animal and human footprints, and it is not necessary that the tracker has been exposed before to the individual whose spoor she/he reads. In order to allow an assessment of how tenable are the interpretations by contemporary hunter-gatherers of prehistoric human footprints, this chapter elucidates methodological aspects of tracking and situates this ability in an epistemological framework.
Frequency Synthesizers Based on Fast-Locking Bang-Bang PLL for Cellular Applications
Authors: Bertulessi Luca
Published: February 2021

The fractional-N frequency synthesis based on Digital Phase Locked Loop (DPLLs) has become a conventional design approach for the new radio wireless applications. The advantage of the digitally-intensive design style is the possibility to implement low-power and very accurate digital calibration techniques. Most of these algorithms run in the background tracking PVT variations and either relax or, in some cases, completely remove the performance limitations due to analog impairments. Moreover, the digital loop filter area is practically negligible with respect to the one in analog PLLs. These benefits become even more relevant in the scaled CMOS technology nodes. This chapter identifies the design parameters of a standard DPLL architecture and proposes a novel locking scheme to overcome the intrinsic limitations of the digital frequency synthesizers approach. To prove this new scheme a sub-6 GHz fractional-N synthesizer has been implemented in 65 nm CMOS. The synthesizer has an output frequency from 3.59 GHz to 4.05 GHz. The integrated output jitter is 182fs and the power consumption of 5.28 mW from 1.2 V power supply leads to a FoM of −247.5 dB. This topology exploits a novel locking technique that guarantee a locking time of 5.6 s, for a frequency step of 364 MHz, despite the use of a single bit phase detector.
Velocity on the Web
Authors: Tommasini Riccardo
Published: February 2021

A new generation of Web Applications is pushing the Web infrastructure to process data as soon as they arrive and before they are no longer valuable. However, the Web infrastructure as it is not adequate, and Stream Processing technologies cannot deal with heterogeneous data streams and events. To solve these issues, we need to investigate how to identify, represent, and process streams and events on the Web. In this chapter, we discuss the recent advancements for taming Velocity on the Web of Data without neglecting Data Variety. Thus, we present a Design Science research investigation that builds on the state of the art of Stream Reasoning and RDF Stream Processing. We present our research results, for representing and processing stream and events on the Web, and we discuss their potential impact.
Tracking Detectors
Authors: Frühwirth Rudolf , Strandlie Are
Published: February 2021

The chapter gives an overview of particle detectors, with the emphasis on tracking detectors. The working principles and the calibration of gaseous, semiconductor, and fiber detectors are explained, followed by a brief review of detector alignment. As an illustration, the tracking systems of the four experiments at the LHC and two non-LHC experiments, Belle II and CBM, are presented.
Track Models
Authors: Frühwirth Rudolf , Strandlie Are
Published: February 2021

The chapter shows how the equations of motion for charged particles in a homogeneous or inhomogeneous magnetic field are solved. Various types of parametrizations are presented, and formulas for track propagation and error propagation are derived. As the effects of the detector material on the trajectory have to be taken into account, the statistical properties of multiple Coulomb scattering, energy loss by ionization, and energy loss by bremsstrahlung are discussed; then it is shown how the effects can be treated in the track reconstruction. As multiple scattering in thin layers and energy loss by bremsstrahlung have distinctive non-Gaussian features, an approximation by normal mixtures is presented.
SUSY breaking constraints on modular flavor S3 invariant SU(5) GUT model
Authors: Du Xiaokang , Wang Fei
Published: February 2021

Abstract

Modular flavor symmetry can be used to explain the quark and lepton flavor structures. The SUSY partners of quarks and leptons, which share the same superpotential with the quarks and leptons, will also be constrained by the modular flavor structure and show a different flavor(mixing) pattern at the GUT scale. So, in realistic modular flavor models with SUSY completion, constraints from the collider and DM constraints can also be used to constrain the possible values of the modulus parameter. In the first part of this work, we discuss the possibility that theS3modular symmetry can be preserved by the fixed points ofT2/ZNorbifold, especially fromT2/Z2. To illustrate the additional constraints from collider etc on modular flavor symmetry models, we take the simplest UV SUSY-completionS3modular invariance SU(5) GUT model as an example with generalized gravity mediation SUSY breaking mechanism. We find that such constraints can indeed be useful to rule out a large portion of the modulus parameters. Our numerical results show that the UV-completed model can account for both the SM (plus neutrino) flavor structure and the collider, DM constraints. Such discussions can also be applied straightforwardly to other modular flavor symmetry models, such asA4orS4models.
Consistency of supersymmetric ’t Hooft anomalies
Authors: Bzowski Adam , Festuccia Guido , Procházka Vladimír
Published: February 2021

Abstract

We consider recent claims that supersymmetry is anomalous in the presence of aR-symmetry anomaly. We revisit arguments that such an anomaly in supersymmetry can be removed and write down an explicit counterterm that accomplishes it. Removal of the supersymmetry anomaly requires enlarging the corresponding current multiplet. As a consequence the Ward identities for other symmetries that are already anomalous acquire extra terms. This procedure can only be impeded when the choice of current multiplet is forced. We show how Wess-Zumino consistency conditions are modified when the anomaly is removed. Finally we check that the modified Wess-Zumino consistency conditions are satisfied, and supersymmetry unbroken, in an explicit one loop computation using Pauli-Villars regulators. To this end we comment on how to use Pauli-Villars to regulate correlators of components of (super)current multiplets in a manifestly supersymmetric way.
The fourth moment of derivatives of Dirichlet L-functions in function fields
Authors: Andrade Julio Cesar , Yiasemides Michael
Published: February 2021

We obtain the asymptotic main term of moments of arbitrary derivatives of L-functions in the function field setting. Specifically, we obtain the first, second, and mixed fourth moments. The average is taken over all non-trivial characters of a prime modulus $$Q \in {\mathbb {F}}_q [T]$$

Q
∈

F
q

[
T
]

, and the asymptotic limit is as $${{\,\mathrm{deg}\,}}Q \longrightarrow \infty $$

deg

Q
⟶
∞

. This extends the work of Tamam who obtained the asymptotic main term of low moments of L-functions, without derivatives, in the function field setting. It is also the function field q-analogue of the work of Conrey, who obtained the fourth moment of derivatives of the Riemann zeta-function.
Assessment of Delays in Emergency Surgical Care and Patient Postoperative Outcomes at a Referral Hospital in Northern Rwanda
Authors: Agasaro Orietta , Munezero Georgette , Wong Rex , Hirwa Aimé , Bekele Abebe
Published: February 2021

Background

Surgical interventions are cost‐effective methods to save lives and prevent disabilities. Surgical delays and access to three Bellwether procedures are key monitoring indicators for universal access to safe and affordable surgical and anesthesia care and health system performance. This study assessed the delays in receiving surgical and anesthesia care for emergency surgical patients at a district hospital in Northern Rwanda.

Methods

A questionnaire was used to survey all emergency surgical patients who presented at the hospital between May and July 2020, to assess the delays in seeking (first) and reaching (second) care. In‐hospital (third) delay and patient outcomes within the first 7 days postsurgery were collected by patient file auditing. Factors associated with third delay were identified through healthcare provider in‐depth interviews.

Results

A total of 106 patients were surveyed, and nine healthcare providers were interviewed. The median was less than a day for first delay, 1 day for second delay, and 16.5 h for third delay for all emergency procedures. 20% of the Bellwether procedures were performed within two hours after arriving at the hospital. Factors affecting the delays included visiting a traditional healer, district of residence, referral system, income status, as well as shortage of surgeons and specialists, surgical supplies, and operating theaters.

Conclusion

Further research to study the cause of delays within the referral system is needed. Surgical outreach, equipment, and infrastructure would help to shorten in‐hospital delays. Longer‐term follow‐up studies on patient complications and outcomes due to delay in surgical care are needed.
Pregnancy-associated breast cancer: nationwide Dutch study confirms a discriminatory aggressive histopathologic profile
Authors: Suelmann B. B. M. , van Dooijeweert C. , van der Wall E. , Linn S. , van Diest P. J.
Published: February 2021

Purpose

Breast cancer is the most common type of malignancy in pregnant women, occurring approximately once in every 3000 pregnancies. Pregnancy-associated breast cancer (PABC) is commonly defined as breast cancer diagnosed during or within one year after pregnancy, and it accounts for up to 6.9% of all breast cancers in women younger than 45 years old. Whether these cancers arise before or during pregnancy, and whether they are stimulated by the high hormonal environment of pregnancy, is currently unknown. This study assesses the histopathological profile of PABC in a large Dutch population-based cohort.

Methods

We identified 744 patients with PABC (in this cohort defined as breast cancer diagnosed during or within 6 months after pregnancy) diagnosed between 1988 and 2019, in the nationwide Dutch Pathology Registry (PALGA). An age-matched PALGA cohort of unselected breast cancer patients (≤ 45 years), diagnosed between 2013 and 2016, was used as a control. Histopathologic features of both cohorts were compared.

Results

The median age of PABC patients was 34.3 years old (range 19–45 years) and most breast cancers were diagnosed during pregnancy (74.2%). As compared to age-matched controls, PABC patients had tumors of higher Bloom–Richardson grade (grade I: 1.5% vs. 12.4%, grade II: 16.9% vs. 31.3%, grade III: 80.3% vs. 39.5%, p < 0.0001). Furthermore, estrogen (ER)- and progesterone (PR)-receptor expression was less frequently reported positive (ER: 38.9% vs. 68.2% and PR: 33.9% vs. 59.0%, p < 0.0001), while a higher percentage of PABC tumors overexpressed HER2 (20.0% vs. 10.0%, p < 0.0001). The most observed intrinsic subtype in PABC was triple-negative breast cancer (38.3% vs. 22.0%, p < 0.0001), whereas hormone-driven cancers were significantly less diagnosed (37.9% vs. 67.3%, p < 0.0001).

Conclusion

This study, based on a large population-based cohort of 744 PABC Dutch patients, underlines the more aggressive histopathologic profile compared to age-matched breast cancer patients ≤ 45 years. Further in-depth genetic analysis will be performed to unravel the origin of this discriminating phenotype. It definitely calls for timely detection and optimal treatment of this small but delicate subgroup of breast cancer patients.
Family Size and Children’s Education: Evidence from the One-Child Policy in China
Authors: Huang Yue
Published: February 2021

Evidence on a causal link between family size and children’s education is still inconclusive. Recent empirical studies have focused heavily on China, exploiting for identification the country’s One-Child Policy (OCP) as an exogenous source of variation in the number of offspring. This literature, however, suffers from measurement error in the key policy variable (individual OCP coverage) and the use of inadequate measures of child quality outcomes (educational attainment). Using a novel and more accurate taxonomy of provincial OCP regulations and studying exclusively post-compulsory schooling outcomes of children that are subject to parental discretion, we find evidence for a sizeable child quantity–quality trade-off in China. Various robustness checks corroborate this conclusion.
A pragmatic approach to the ontology of models
Authors: Antoniou Antonis
Published: February 2021

What are scientific models? Philosophers of science have been trying to answer this question during the last three decades by putting forward a number of different proposals. Some say that models are best understood as abstract Platonic objects or fictional entities akin to Sherlock Holmes, while others focus on their mathematical nature and see them as set theoretical structures. Although each account has its own strengths in offering various insights on the nature of models, several objections have been raised against these views which still remain unanswered, making the debate on the ontology of models seem unresolvable. The primary aim of this paper is to show that a large part of these difficulties stems from an inappropriate reading of the main question on the ontology of models as a purely metaphysical question. Building on Carnap, it is argued that the question of the ontology of scientific models is either (i) an internal theoretical question within an already accepted linguistic framework or (ii) an external practical question regarding the choice of the most appropriate form of language in order to describe and explain the practice of scientific modelling. The main implication of this view is that the question of the ontology of models becomes a means of probing other related questions regarding the overall practice of scientific modelling, such as questions on the capacity of models to provide knowledge and the relation of models with background theories.
Investigations on arc brazing for galvanized heavy steel plates in steel and shipbuilding
Authors: Andreazza Philipp , Gericke Andreas , Henkel Knuth-Michael
Published: February 2021

Arc brazing with low-melting copper-based filler materials, which has long been established and standardized in the thin sheet sector, offers numerous advantages in the processing of predominantly electrolytically galvanized steel structures. In steel and shipbuilding, on the other hand, equipment parts made of thick steel sheets are hot-dip galvanized at low cost and with good corrosion-inhibiting properties. Quality welding of such constructions is not possible without special precautions such as removing the zinc layer and subsequent recoating. With regard to greater plate thicknesses, arc brazing was analyzed in these investigations as an alternative joining method with regard to its suitability for practical use. Within the scope of the investigations, CuSi3Mn, CuMn12Ni2, and four different aluminum bronzes were examined on different sheet surface conditions with regard to the geometrical and production parameters. This was carried out by build-up and connection brazing, executed as butt and cross joints. Quasi-static tensile tests and fatigue tests were used to assess the strength behavior. In addition, metallographic analyses are carried out as well as hardness tests. The suitability for multi-layer brazing and the tendency to distortion were also investigated, as well as the behavior of arc brazed joints under corrosive conditions.
The relationship between trend and volume on the bitcoin market
Authors: Szetela Beata , Mentel Grzegorz , Bilan Yuriy , Mentel Urszula
Published: February 2021

The aim of the paper is to verify the existence of short- and long-term relationships between the strength of a trend and the volume in bullish and bearish cryptocurrency markets. We applied the vector error correction model to bitcoin daily data from 14.01.2015 to 22.12.2019. Based on the prices and following Wilder’s algorithm, the average directional movement index was calculated, and upward and downward trend periods were determined. No long-term relationship was found to exist between the strength of a trend and the volume in both bearish and bullish markets. Hence, trends do not react to volume changes. However, a long-term relationship exists between volume and trend—but only for the downward trend—with an adjustment speed of 88%. In the short-term, a statistically significant but very weak dependency is revealed; hence, the conclusion that trend strength is insensitive to volume changes can be reached.