bluuebunny/crossref_metadata_2025 huggingface dataset:
Multimodal surface-wave tomography to obtain S- and P-wave velocities applied to the recordings of unmanned aerial vehicle deployed sensors
Authors: Khosro Anjom Farbod , Browaeys Thomas Jules , Socco Laura Valentina
Published: March 2021

Exploration seismic surveys in hard-to-access areas such as foothills and forests are extremely challenging. The Multiphysics Exploration Technologies Integrated System (METIS) research project was initiated to design an exploration system, facilitating the acquisition in these areas by delivering the receivers from the sky using unmanned aerial vehicles. Air dropping of the sensors in vegetated areas results in an irregular geometry for the acquisition. This irregularity can limit the application of conventional surface wave methods. We have developed a surface wave workflow for estimating the S-wave velocity ([Formula: see text]) and P-wave velocity ([Formula: see text]) models and that supports the irregular geometry of the deployed sources and receivers. The method consists of a multimodal surface-wave tomography (SWT) technique to compute the [Formula: see text] model and a data transform method (the wavelength/depth [W/D] method) to determine the Poisson’s ratio and [Formula: see text] model. We applied the method to the METIS’s first pilot records, which were acquired in the forest of Papua New Guinea. Application of SWT to the data resulted in the first 90 m of the [Formula: see text] model. The W/D method provided the Poisson’s ratio averaged over the area and the [Formula: see text] model between 10 and 70 m from the surface. The impact of the acquisition scale and layout on the resolution of the estimated model and the advantages of including the higher modes of surface waves in the tomographic inversion are assessed in detail. The presence of shots from diverse site locations significantly improves the resolution of the obtained model. Including the higher modes enhances the data coverage and increases the investigation depth.
Glassy gravity
Authors: De Giuli Eric , Zee A.
Published: March 2021

Euclidean quantum gravity is reconsidered, in the conformal mode approximation. Applying techniques from glass theory, we argue that the Euclidean partition function hides metastable states, which can be counted. This may reconcile conflicting results on the uniqueness of the de Sitter vacuum, and may be relevant to the cosmological constant problem.
A field theory in Randers-Finsler spacetime
Authors: Silva J. E. G.
Published: March 2021

Finsler geometry is a natural arena to investigate the physics of spacetimes with local Lorentz violation. The directional dependence of the Finsler metric provides a way to encode the Lorentz-violating effects into the geometric structure of the spacetime. Here, a classical field theory is proposed in a special Finsler geometry, the so-called Randers-Finsler spacetime, where the Lorentz violation is produced by a background vector field. By promoting the Randers-Finsler metric to a differential operator, a Finsler-invariant action for the scalar, gauge and fermions are proposed. The theory contains nonlocal terms, as in the Very Special Relativity based theories. By expanding the Lagrangian, minimal and nonminimal Standard Model Extension terms arise, revealing a perturbative Lorentz violation. For a CPT-even term, the Carrol-Field-Jackiw and derivative extensions are obtained.
Continuous photon Hall effect on metal surface
Authors: Gao Qi , Zhou Yun-Song , Zhao Li-Ming
Published: March 2021

The continuous photon Hall effect excited in a surface plasmon polariton system is proposed and realized theoretically, in which the parallel incident light illuminates the small ball nearing the surface. The scattering direction can be continually modulated in the large range of almost 180 degree by the elliptical polarization state of the incident light. The physical reason is displayed intuitively by the component waves interference principle.
Effect of magnetism on lattice dynamics in metallic chromium
Authors: Dubiel Stanisław M. , Żukrowski Jan
Published: March 2021

A single-crystal sample of chromium doped with

Sn was studied by means of a transmission Mössbauer spectroscopy in the temperature range of

310–315 K. An anomaly in the temperature behavior of the center shift was found at

313 K, a temperature that coincides well with the Néel temperature of chromium. The anomaly gives evidence that the vibrations of atoms in the studied system are affected by the magnetism.
Broadband seismic metamaterial with an improved cylinder by introducing plus-shaped structure
Authors: Xu Rui , Muzamil Muhammad , Fan Li , Yuan Keke , Yang Hongwu , Du Qiujiao
Published: March 2021

The narrow bandgap of a seismic metamaterial dramatically limits its application in attenuating seismic waves for securing buildings. This research proposes an improved cylinder-type seismic metamaterial by introducing plus-shaped to widen the bandgap. The propagation of seismic waves through a three-dimensional sample of seismic metamaterial is calculated to show its efficiency of the earthquake shielding using the finite-element method based on Floquet-Bloch theory. By comparison to the common seismic metamaterial consisting of simple cylinder structures, it is found that our metamaterial based on cylinder with plus-shaped structures can yield a three times relative bandgap width for seismic surface waves, which is more suitable for practical applications. Moreover, the bandgap depends on the constraint of geometric parameters and elastic parameters, and can be easily tuned to higher frequency for other phenomena such as vibration and noise attenuation by tailoring those parameters.
Symmetry breaking in single-crystal SrTiO3 plates: EPR manifestations
Authors: Gabbasov B. F. , Gracheva I. N. , Rodionov A. A. , Kiiamov A. G. , Nikitin S. I. , Zverev D. G. , Trepakov V. A. , Dejneka A. , Jastrabik L. , Yusupov R. V.
Published: March 2021

Results of the electron paramagnetic resonance (EPR) studies of Fe3+ and Mn4+ impurity centers in high-quality single-crystal SrTiO3 plates with thickness

are presented. Impurities served the paramagnetic probes of the crystal structure. Analysis of the collected data indicates that the symmetry of the crystal structure of thin (001) and (110) oriented strontium titanate plates above

lowers in the bulk from the cubic to tetragonal. The structure of this high-temperature tetragonal state is different from that of the conventional low-temperature antiferrodistorsive phase and has not been reported for SrTiO3 before. It is shown that the effect does not originate from the residual stress; its magnitude and particular manifestations depend on plate orientation, surface quality and geometry of a sample. Peculiarities of the observed phenomenon are presented and the possible scenario of its realization is discussed.
Cerebral Emboli Monitoring Using Transcranial Doppler Ultrasonography in Adults and Children: A Review of the Current Technology and Clinical Applications in the Perioperative and Intensive Care Setting
Authors: Kussman Barry D. , Imaduddin Syed M. , Gharedaghi Mohammad Hadi , Heldt Thomas , LaRovere Kerri
Published: March 2021

Transcranial Doppler (TCD) ultrasonography is the only noninvasive bedside technology for the detection and monitoring of cerebral embolism. TCD may identify patients at risk of acute and chronic neurologic injury from gaseous or solid emboli. Importantly, a window of opportunity for intervention—to eliminate the source of the emboli and thereby prevent subsequent development of a clinical or subclinical stroke—may be identified using TCD. In this review, we discuss the application of TCD sonography in the perioperative and intensive care setting in adults and children known to be at increased risk of cerebral embolism. The major challenge for evaluation of emboli, especially in children, is the need to establish the ground truth and define true emboli identified by TCD. This requires the development and validation of a predictive TCD emboli monitoring technique so that appropriately designed clinical studies intended to identify specific modifiable factors and develop potential strategies to reduce pathologic cerebral embolic burden can be performed.
The Anesthesiology Milestones 2.0: An Improved Competency-Based Assessment for Residency Training
Authors: Ambardekar Aditee P. , Walker K. Karisa , McKenzie-Brown Anne Marie , Brennan Kaitlyn , Jackson Chelsia , Edgar Laura , Ellinas Herodotos , Long Timothy R. , Trombetta Carlos E. , Laskey Martin G. , Wargo Bradley W. , Dainer Rupa J. , Draconi Crys S. , Mitchell John D.
Published: March 2021

The evolution of medical education, from a time-based to a competency-based platform, began nearly 30 years ago and continues to slowly take shape. The development of valid and reproducible assessment tools is the first step. Medical educators across specialties acknowledge the challenges and remain motivated to develop a relevant, generalizable, and measurable system. The Accreditation Council for Graduate Medical Education (ACGME) remains committed to its responsibility to the public by assuring that the process and outcome of graduate medical education in the nation’s residency programs produce competent, safe, and compassionate doctors. The Milestones Project is the ACGME’s current strategy in the evolution to a competency-based system, which allows each specialty to develop its own set of subcompetencies and 5-level progression, or milestones, along a continuum of novice to expert. The education community has now had nearly 5 years of experience with these rubrics. While not perfect, Milestones 1.0 provided important foundational information and insights. The first iteration of the Anesthesiology Milestones highlighted some mismatch between subcompetencies and current and future clinical practices. They have also highlighted challenges with assessment and evaluation of learners, and the need for faculty development tools. Committed to an iterative process, the ACGME assembled representatives from stakeholder groups within the Anesthesiology community to develop the second generation of Milestones. This special article describes the foundational data from Milestones 1.0 that was useful in the development process of Milestones 2.0, the rationale behind the important changes, and the additional tools made available with this iteration.
A lineage-specific requirement for YY1 Polycomb Group protein function in early T cell development
Authors: Assumpção Anna L. F. V. , Fu Guoping , Singh Deependra K. , Lu Zhanping , Kuehnl Ashley M. , Welch Rene , Ong Irene M. , Wen Renren , Pan Xuan
Published: March 2021

Yin Yang 1 (YY1) is a ubiquitous transcription factor and mammalian Polycomb Group protein (PcG) with important functions for regulating lymphocyte development and stem cell self-renewal. YY1 mediates stable PcG-dependent transcriptional repression via recruitment of PcG proteins that result in histone modifications. Many questions remain unanswered regarding how cell- and tissue-specificity is achieved by PcG proteins. Here, we demonstrate that a conditional knockout of Yy1 in the hematopoietic system results in an early T cell developmental blockage at the double negative (DN) 1 stage with reduced Notch1 signaling. There is a lineage-specific requirement for YY1 PcG function. YY1 PcG domain is required for T and B cell development but not necessary for myeloid cells. YY1 functions in early T cell development are multicomponent and involve both PcG-dependent and -independent regulations. Although YY1 promotes early T cell survival through its PcG function, its function to promote the DN1-to-DN2 transition and Notch1 expression and signaling is independent of its PcG function. Our results reveal how a ubiquitously expressed PcG protein mediates lineage-specific and context-specific functions to control early T cell development.
Use of chicken feather meal fermented with Bacillus subtilis in diets to increase the digestive enzymes activity and nutrient digestibility of silver pompano Trachinotus blochii (Lacepede, 1801)
Authors: Adelina Adelina , Feliatra Feli , Siregar Yusni Ikhwan , Putra Iskandar , Suharman Indra
Published: March 2021

Background: Feather has the potential to be used as a fish feed ingredient because it has high protein content (80-85%), and is rich in amino acids arginine, leucine, isoleucine and valine. However, the protein consists mainly of keratin, which is classified as fiber that is difficult to digest. Therefore, to improve digestibility, the keratin protein is degraded using microbial Bacillus subtilis. This study aimed to determine the digestibility of fermented feather meal (FFM) in silver pompano (Trachinotus blochii) diets and to observe the histological structure of their intestines after digestion.

Methods: The method used was a one factor experiment with five treatments and three replications each, which were: diet without FFM, diet containing 10% FFM, 20%, 30% and 40%. The diets were given to juvenile silver pompano (with average body weight of 8.56 ± 0.18 g) and stocked in 15 similar 20-L plastic jars with 10 fish per jar in a density of 100 L capacity container. The experimental diets were given three times daily at approximately 8.00 AM, 12.00 PM and 5.00 PM to apparent satiation for 60 days.

Results: The results showed that the use of FFM increased the activity of digestive enzymes (protease and lipase), but reduced the amylase activity of silver pompano, which was significantly different between treatments (P <0.05). Meanwhile, the diet containing 20% FFM produced the highest feed and protein, which are 37.05% and 67.24%, respectively. This was significantly different from other treatments (P <0.05), and was effectively absorbed by fish intestines.

Conclusion: The addition of chicken feather meal fermented with Bacillus subtilis could increase the activity of protease and lipase enzymes and nutrient digestibility of silver pompano but not amylase activity.
Application of Artifi cial Intelligence Systems in Education in China and Japan
Authors: Nevezhin Victor
Published: March 2021

In the era of development of information technology and computing technology, the development and application of artificial intelligence (AI) technologies, computer technology, which is designed to perform specialized tasks and expand human capabilities in the field of machine learning, are relevant and debatable. This article provides an overview of the development of AI in Asian countries such as China and Japan. The countries under consideration are among the leading countries and their experience in AI can serve as a basis for other AI developers to develop new technologies based on existing developments. A number of approaches of the Japanese and Chinese communities to the development of artificial intelligence, including startups, are considered. Ideas and requirements for the development of educational systems using AI from corporations, regulatory bodies and their government programs, associations and AI developers are given. The article provides a comparative analysis of two Asian countries based on their priorities and approaches that affect the speed of development of new technologies in the field of AI.
Formation of Universal Competencies of Undergraduate Students of Pedagogical Directions
Authors: Minina O.
Published: March 2021

The aim of the research was to develop and implement a teachers training master degree program with active integration of soft skills at all the stages to form students’ system and critical thinking, project management skills, teamwork and leadership, communication and cross-cultural interaction skills. To solve these problems, the program included specialized practice-orientated courses based on the principles of pedagogical ergonomics and the latest technologies (ball-rating system, workshop, case study, “agile” principle, pedagogical situations’ modeling and others). The research resulted is a unique, effective and validated program and a set of training materials to develop universal competencies of master degree students.
Las víctimas de conflictos armados como sujetos desarrollables: políticas de la ayuda humanitaria y cooperación al desarrollo de la Unión Europea (2010-2014)
Authors: Fuentes Becerra Diana Margarita
Published: March 2021

La oposición planteada entre la situación de victimización y la ciudadanía es una premisa que generalmente se da por sentada en políticas públicas y en intervenciones de la cooperación internacional. Este artículo plantea, a través de la caracterización de las políticas de la ayuda humanitaria y la cooperación al desarrollo de la Unión Eu­ropea, cuáles son los supuestos de tal oposición, demostrando que la noción de víctima se asocia a un espacio humanitario donde se privilegia la representación del extraño que sufre, y, por otro lado, se reproducen imágenes del ciudadano como aquel sujeto autónomo que puede autoabastecerse en el mercado. Así, al confluir estas políticas en lo que se ha denominado el vínculo entre ayuda de emergencia y desarrollo se termina por representar a la víctima como un sujeto desarrollable.
The Private Impact of Public Data: Landsat Satellite Maps Increased Gold Discoveries and Encouraged Entry
Authors: Nagaraj Abhishek
Published: March 2021

How does public data shape the relative performance of incumbents and entrants in the private sector? Using a simple theoretical framework, I argue that public data reduces investment uncertainty, facilitates the discovery of new market opportunities, and increases the relative market share of new entrants relative to incumbents. I shed light on these predictions by estimating the impact of public data from Landsat, a U.S. National Aeronautics and Space Administration satellite mapping program, on the discovery rates of new deposits by incumbents (seniors) and entrants (juniors) in the gold exploration industry. I exploit idiosyncratic timing variation and cloud cover in Landsat coverage across regions to identify the causal effect of public data on the patterns of gold discovery. I find that Landsat data nearly doubled the rate of significant gold discoveries after a region was mapped and increased the market share of new entrants from about 10% to 25%. Public data seem to play an important, yet relatively underexplored, role in driving performance differences across firms.

This paper was accepted by Ashish Arora, entrepreneurship and innovation.
Combining Probability Forecasts: 60% and 60% Is 60%, but Likely and Likely Is Very Likely
Authors: Mislavsky Robert , Gaertig Celia
Published: March 2021

How do we combine others’ probability forecasts? Prior research has shown that when advisors provide numeric probability forecasts, people typically average them (i.e., they move closer to the average advisor’s forecast). However, what if the advisors say that an event is “likely” or “probable?” In eight studies (n = 7,334), we find that people are more likely to act as if they “count” verbal probabilities (i.e., they move closer to certainty than any individual advisor’s forecast) than they are to “count” numeric probabilities. For example, when the advisors both say an event is “likely,” participants will say that it is “very likely.” This effect occurs for both probabilities above and below 50%, for hypothetical scenarios and real events, and when presenting the others’ forecasts simultaneously or sequentially. We also show that this combination strategy carries over to subsequent consumer decisions that rely on advisors’ likelihood judgments. We discuss and rule out several candidate mechanisms for our effect.

This paper was accepted by Yuval Rottenstreich, decision analysis.
Otitis externa: a roundtable discussion
Authors: Paterson Sue , Nett Claudia , Neuber Ariane , Maddison Jill , Ackerman Nicola , Fitzgerald Ronan , Noli Chiara , Warren Sarah
Published: March 2021

Otitis externa is a common problem in both primary care and referral practice. A wide range of factors contribute to the successful management of disease. A logical approach and investigation are important and should always include an appreciation of underlying primary causes, predisposing and perpetuating factors, and secondary infection. Cytology is essential to help choose appropriate therapy and represents an opportunity to use the expertise of the nurses within the veterinary team. COVID-19 has forced many veterinary professionals to use remote consultation techniques to provide care for patients and it may be that some of the lessons we have learned during lockdown can be applied to our working practices to improve the level of veterinary care in the future. The selection of appropriate topical anti-microbial and anti-inflammatory drugs is, of course, important but without good levels of owner compliance even the best therapy is ineffective. This article presents the outcome of a workshop in which a group of experts discussed many of these topics.
How to interpret an electrocardiogram
Authors: Smith Sarah
Published: March 2021

Electrocardiography is the ultimate tool for diagnosing suspected cardiac arrhythmia, and the required equipment is readily available to an equine practitioner. Careful interpretation is essential to determine whether an arrhythmia is significant, either as a cause of poor performance or as a risk for collapse and sudden death. A good quality electrocardiogram recording is essential, usually an exercising electrocardiogram and a recording over 24 hours. Electrocardiographical interpretation is aided by modern electrocardiogram analysis software, and technology enables access to a second opinion when required. Vagally-mediated arrhythmias are common in horses at rest, but should be overridden by exercise. Atrial fibrillation or frequent ectopic beats during exercise warrants further cardiac evaluation.
Spring poisoning hazards
Authors: Bates Nicola
Published: March 2021

Poisoning can be seasonal. Potential toxic hazards in the spring include adders, which emerge from hibernation as the weather warms. Adders may not be seen to bite a horse, but envenomation should be considered in a horse with localised limb swelling that spreads up the leg. There are several spring-flowering plants which contain toxic compounds such as cardiogenic glycosides (foxglove, lily of the valley, oleander), protoanemonin (Hellebore) and grayanotoxins (Pieris and Rhododendron). Saplings of sycamore are a spring source of hypoglycin A which causes atypical myopathy in horses. Treating plant poisoning in horses generally involves removing the plant, providing good quality food and giving supportive care. Managing the effects of adder bite is supportive, centring around administration of specific antivenom.
Driving through change at speed. Opportunity conditions and entrepreneurial responses in the history of the express industry
Authors: Gil-López Águeda , San Román Elena , Jack Sarah , Zozimo Ricardo
Published: March 2021

A lo largo de la historia se han sucedido diferentes contextos en los que ciertas condiciones y acontecimientos han creado oportunidades emprendedoras. Este artículo se enmarca en la segunda y tercera oleadas industrializadoras para analizar el nacimiento y evolución histórica de la industria del transporte urgente, cuyos orígenes se remontan a mediados del siglo xix en Estados Unidos. A través de un razonamiento secuencial, este trabajo determina cómo diferentes contextos históricos crearon oportunidades empresariales, y cómo los emprendedores del sector del transporte urgente las aprovecharon por medio de respuestas innovadoras que, con el tiempo, fueron transformando la naturaleza de esta industria.
Efficient demodulation scheme based on adaptive clock extraction and
mapping-sampling for a mobile OCC system
Authors: Huang Zheng , He Jing , Yu Ke , Li Wei
Published: March 2021

An efficient demodulation scheme based on adaptive clock extraction and mapping-sampling is proposed and experimentally demonstrated for mobile optical camera communication (OCC) systems. For the proposed scheme, it can effectively improve the system performance in mobile OCC. The bit error rate (BER) performance of the proposed scheme and the other existing schemes are compared. The experimental results show that under the speed from 0.4 m/s to 0.7 m/s, it can significantly improve the system performance using the adaptive clock extraction and the mapping-sampling scheme in mobile OCC systems. Compared with the length estimation scheme, when the speed is 0.7 m/s, the BER can be improved from

9.14

×

10

−
2

to

3.16

×

10

−
4

at the exposure time of 1/12,000 s using the proposed scheme. In addition, the required memory and processing time of the proposed scheme are analyzed, which indicates that the proposed scheme has negligible influence on memory overhead and computational complexity.
Polarized vector optical compact bright pulse in a weakly anisotropic nonlocal Kerr-like waveguide
Authors: Donkeng Hatou-Yvelin , Kenmogne Fabien , Pokam Nguewawe Chancelor , Yemélé David
Published: March 2021

A coupled nonlocal nonlinear Schrödinger equation describing the propagation of the polarized vector light pulses in a weakly anisotropic waveguide with nearly instantaneous nonlinear response is introduced in the framework of the slowly varying envelope. This new equation reduces to the scalar nonlocal nonlinear Schrödinger equation in the particular case of a linear polarization of the light beam and, in the dispersionless regime, can support, in addition to the rectilinear polarization, the stable circularly and elliptically polarized compact bright (CB) pulse with an arbitrary nonlinear phase. More interesting, the exact analytical expression of the two-cycle circularly polarized CB pulse is also derived. We believe the results provide useful insight into the interaction between polarized CB pulses, namely, the strength and the period of interaction. It appears that this interaction results from the phenomenon of energy exchange between the two components of CB light pulses and can be suppressed by adjusting either their separation distance and the phase difference or the amplitudes of the two pulses. The efficiency of these analytical results has been confirmed by numerical simulations.
LiDAR-derived digital holograms for automotive head-up displays
Authors: Skirnewskaja Jana , Montelongo Yunuen , Wilkes Phil , Wilkinson Timothy D.
Published: March 2021

A holographic automotive head-up display was developed to project 2D and 3D ultra-high definition (UHD) images using LiDAR data in the driver’s field of view. The LiDAR data was collected with a 3D terrestrial laser scanner and was converted to computer-generated holograms (CGHs). The reconstructions were obtained with a HeNe laser and a UHD spatial light modulator with a panel resolution of 3840×2160 px for replay field projections. By decreasing the focal distance of the CGHs, the zero-order spot was diffused into the holographic replay field image. 3D holograms were observed floating as a ghost image at a variable focal distance with a digital Fresnel lens into the CGH and a concave lens.
Vector soliton dynamics in a high-repetition-rate fiber laser
Authors: Lin Wei , Wang Wenlong , He Bin , Chen Xuewen , Hu Xu , Guo Yuankai , Xu Yue , Wei Xiaoming , Yang Zhongmin
Published: March 2021

The existence of vector solitons that arise from the birefringence nature of optical fibers has been increasingly of interest for the stability of mode-locked fiber lasers, particularly for those operating in the high-fundamental-repetition-rate regime, where a large amount of fiber birefringence is required to restore the phase relation between the orthogonally polarized vector solitons, resulting in stable mode-locking free of polarization rotation. These vector solitons can exhibit diverse time-varying polarization dynamics, which prevent industrial and scientific applications requiring stable and uniform pulse trains at high fundamental repetition rates. This pressing issue, however, has so far been rarely studied. To this end, here we theoretically and experimentally dissect the formation of vector solitons in a GHz-repetition-rate fiber laser and investigate effective methods for suppressing roundtrip-to-roundtrip polarization dynamics. Our numerical model can predict both dynamic and stable regimes of high-repetition-rate mode-locking by varying the amount of fiber birefringence, resulting in the polarization rotation vector soliton (PRVS) and linearly polarized soliton (LPS), respectively. These dynamic behaviors are further studied by using an analytical approach. Interestingly, our theoretical results indicate a cavity-induced locking effect, which can be a complementary soliton trapping mechanism for the co-propagating solitons. Finally, these theoretical predications are experimentally verified, and we obtain both PRVS and LPS by adjusting the intracavity fiber birefringence.
The capacity of origins to load MCM establishes replication timing patterns
Authors: Dukaj Livio , Rhind Nicholas
Published: March 2021

Loading of the MCM replicative helicase at origins of replication is a highly regulated process that precedes DNA replication in all eukaryotes. The stoichiometry of MCM loaded at origins has been proposed to be a key determinant of when those origins initiate replication during S phase. Nevertheless, the genome-wide regulation of MCM loading stoichiometry and its direct effect on replication timing remain unclear. In order to investigate why some origins load more MCM than others, we perturbed MCM levels in budding yeast cells and, for the first time, directly measured MCM levels and replication timing in the same experiment. Reduction of MCM levels through degradation of Mcm4, one of the six obligate components of the MCM complex, slowed progression through S phase and increased sensitivity to replication stress. Reduction of MCM levels also led to differential loading at origins during G1, revealing origins that are sensitive to reductions in MCM and others that are not. Sensitive origins loaded less MCM under normal conditions and correlated with a weak ability to recruit the origin recognition complex (ORC). Moreover, reduction of MCM loading at specific origins of replication led to a delay in their replication during S phase. In contrast, overexpression of MCM had no effects on cell cycle progression, relative MCM levels at origins, or replication timing, suggesting that, under optimal growth conditions, cellular MCM levels are not limiting for MCM loading. Our results support a model in which the loading capacity of origins is the primary determinant of MCM stoichiometry in wild-type cells, but that stoichiometry is controlled by origins’ ability to recruit ORC and compete for MCM when MCM becomes limiting.
Negative density-dependent dispersal in tsetse (Glossina spp): An artefact of inappropriate analysis
Authors: Hargrove John W. , Van Sickle John , Vale Glyn A. , Lucas Eric R.
Published: March 2021

Published analysis of genetic material from field-collected tsetse (Glossinaspp, primarily from the Palpalis group) has been used to predict that the distance (δ) dispersed per generation increases as effective population densities (De) decrease, displaying negative density-dependent dispersal (NDDD). Using the published data we show this result is an artefact arising primarily from errors in estimates ofS, the area occupied by a subpopulation, and thereby inDe. The errors arise from the assumption thatScan be estimated as the area (S^) regarded as being covered by traps. We use modelling to show that such errors result in anomalously high correlations betweenδ^andS^and the appearance of NDDD, with a slope of -0.5 for the regressions of log(δ^) on log(D^e), even in simulations where we specifically assume density-independent dispersal (DID). A complementary mathematical analysis confirms our findings. Modelling of field results shows, similarly, that the false signal of NDDD can be produced by varying trap deployment patterns. Errors in the estimates ofδin the published analysis were magnified because variation in estimates ofSwere greater than for all other variables measured, and accounted for the greatest proportion of variation inδ^. Errors in census population estimates result from an erroneous understanding of the relationship between trap placement and expected tsetse catch, exacerbated through failure to adjust for variations in trapping intensity, trap performance, and in capture probabilities between geographical situations and between tsetse species. Claims of support in the literature for NDDD are spurious. There is no suggested explanation for how NDDD might have evolved. We reject the NDDD hypothesis and caution that the idea should not be allowed to influence policy on tsetse and trypanosomiasis control.
The PCOC Symptom Assessment Scale (SAS): A valid measure for daily use at point of care and in palliative care programs
Authors: Daveson Barbara A. , Allingham Samuel Frederic , Clapham Sabina , Johnson Claire E. , Currow David C. , Yates Patsy , Eagar Kathy
Published: March 2021

Background

Very few measures are used successfully as part of routine care within national palliative care outcome programs. Only a handful of studies examine these measures. The aim of this study is to evaluate the validity of a measure used in a national outcomes program: the Palliative Care Outcomes Collaboration Symptom Assessment Scale (PCOC SAS).

Methods

A retrospective multi-site cohort study with secondary analysis of routinely collected patient-level data to assess PCOC SAS’s internal consistency, construct validity, reliability, interpretability, acceptability and sensitivity. The analyses used two sets, with data collected by inpatient and community palliative care services registered with the Australian national PCOC.

Results

Dataset one included 1,117 patients receiving palliative care from 21 services. Dataset two included 5,294 patients receiving palliative care from 119 PCOC services. PCOC SAS demonstrated the ability to detect and discriminate distress by palliative care phase, functional status and diagnosis. Excellent and good convergent and discriminant validity were demonstrated. Fair through to substantial inter-rater and intra-rater reliability levels were evidenced. Sufficient interpretability resulted along with necessary levels of acceptability and sensitivity.

Conclusion

PCOC SAS is a valid and reliable patient-reported outcome measure suitable for use in routine clinical care with patients requiring palliative and or end-of-life care, including in national outcomes programs.
Stool metabolome-microbiota evaluation among children and adolescents with obesity, overweight, and normal-weight using 1H NMR and 16S rRNA gene profiling
Authors: Jaimes José Diógenes , Slavíčková Andrea , Hurych Jakub , Cinek Ondřej , Nichols Ben , Vodolánová Lucie , Černý Karel , Havlík Jaroslav
Published: March 2021

Characterization of metabolites and microbiota composition from human stool provides powerful insight into the molecular phenotypic difference between subjects with normal weight and those with overweight/obesity. The aim of this study was to identify potential metabolic and bacterial signatures from stool that distinguish the overweight/obesity state in children/adolescents. Using1H NMR spectral analysis and 16S rRNA gene profiling, the fecal metabolic profile and bacterial composition from 52 children aged 7 to 16 was evaluated. The children were classified into three groups (16 with normal-weight, 17 with overweight, 19 with obesity). The metabolomic analysis identified four metabolites that were significantly different (p < 0.05) among the study groups based on one-way ANOVA testing: arabinose, butyrate, galactose, and trimethylamine. Significantly different (p < 0.01) genus-level taxa based on edgeR differential abundance tests were genusEscherichiaandTyzzerellasubgroup 3. No significant difference in alpha-diversity was detected among the three study groups, and no significant correlations were found between the significant taxa and metabolites. The findings support the hypothesis of increased energy harvest in obesity by human gut bacteria through the growing observation of increased fecal butyrate in children with overweight/obesity, as well as an increase of certain monosaccharides in the stool. Also supported is the increase of trimethylamine as an indicator of an unhealthy state.
A randomised trial examining inflammatory signaling in acutely induced hyperinsulinemia and hyperlipidemia in normal weight women-the reprometabolic syndrome
Authors: Tannous Andrew , Bradford Andrew P. , Kuhn Katherine , Fought Angela , Schauer Irene , Santoro Nanette
Published: March 2021

Context

Obesity, is a state of chronic inflammation, characterized by elevated lipids, insulin resistance and relative hypogonadotropic hypogonadism. We have defined the accompanying decreased Luteinizing Hormone (LH), Follicle-Stimulating Hormone (FSH), ovarian steroids and reduced pituitary response to Gonadotropin-releasing Hormone (GnRH) as Reprometabolic syndrome, a phenotype that can be induced in healthy normal weight women (NWW) by acute infusion of free fatty acids and insulin.

Objective

To identify potential mediators of insulin and lipid-related reproductive endocrine dysfunction.

Design, setting, participants

Secondary analysis of crossover study of eumenorrheic reproductive aged women of normal Body Mass Index (BMI) (<25 kg/m2) at an academic medical center.

Intervention

Participants underwent 6-hour infusions of either saline/heparin or insulin plus fatty acids (Intralipid plus heparin), in the early follicular phase of sequential menstrual cycles, in random order. Euglycemia was maintained by glucose infusion. Frequent blood samples were obtained.

Main outcome measures

Pooled serum from each woman was analyzed for cytokines, interleukins, chemokines, adipokines, Fibroblast Growth Factor-21 (FGF-21) and markers of endoplasmic reticulum (ER) stress (CHOP and GRP78). Wilcoxon signed-rank tests were used to compare results across experimental conditions.

Results

Except for Macrophage Inflammatory Protein-1β (MIP-1β), no significant differences were observed in serum levels of any of the inflammatory signaling or ER stress markers tested.

Conclusion

Acute infusion of lipid and insulin, to mimic the metabolic syndrome of obesity, was not associated with an increase in inflammatory markers. These results imply that the endocrine disruption and adverse reproductive outcomes of obesity are not a consequence of the ambient inflammatory environment but may be mediated by direct lipotoxic effects on the hypothalamic-pituitary-ovarian (HPO) axis.
The impact of antenatal syphilis point of care testing on pregnancy outcomes: A systematic review
Authors: Brandenburger Dana , Ambrosino Elena
Published: March 2021

Background

Mother-to-child transmission of syphilis remains a leading cause of neonatal death and stillbirth, disproportionally affecting women in low-resource settings where syphilis prevalence rates are high and testing rates low. Recently developed syphilis point-of-care tests (POCTs) are promising alternatives to conventional laboratory screening in low-resource settings as they do not require a laboratory setting, intensive technical training and yield results in 10–15 minutes thereby enabling both diagnosis and treatment in a single visit. Aim of this review was to provide clarity on the benefits of different POCTs and assess whether the implementation of syphilis POCTs is associated with decreased numbers of syphilis-related adverse pregnancy outcomes.

Methods

Following the PRISMA guidelines, three electronic databases (PubMed, Medline (Ovid), Cochrane) were systematically searched for intervention studies and cost-effectiveness analyses investigating the association between antenatal syphilis POCT and pregnancy outcomes such as congenital syphilis, low birth weight, prematurity, miscarriage, stillbirth as well as perinatal, fetal or infant death.

Results

Nine out of 278 initially identified articles were included, consisting of two clinical studies and seven modelling studies. Studies compared the effect on pregnancy outcomes of treponemal POCT, non-treponemal POCT and dual POCT to laboratory screening and no screening program. Based on the clinical studies, significantly higher testing and treatment rates, as well as a significant reduction (93%) in adverse pregnancy outcomes was reported for treponemal POCT compared to laboratory screening. Compared to no screening and laboratory screening, modelling studies assumed higher treatment rates for POCT and predicted the most prevented adverse pregnancy outcomes for treponemal POCT, followed by a dual treponemal and non-treponemal POCT strategy.

Conclusion

Implementation of treponemal POCT in low-resource settings increases syphilis testing and treatment rates and prevents the most syphilis-related adverse pregnancy outcomes compared to no screening, laboratory screening, non-treponemal POCT and dual POCT. Regarding the benefits of dual POCT, more research is needed. Overall, this review provides evidence on the contribution of treponemal POCT to healthier pregnancies and contributes greater clarity on the impact of diverse diagnostic methods available for the detection of syphilis.
Asymptomatic Plasmodium infection and associated factors among pregnant women in the Merti district, Oromia, Ethiopia
Authors: Subussa Bereket Wake , Eshetu Teferi , Degefa Teshome , Ali Musa Mohammed
Published: March 2021

Background

Asymptomatic Plasmodium infection (API) that occurs during pregnancy increases the risk of stillbirths, abortion, premature delivery, and low birth weight. API also hinders the control and prevention of malaria as infected hosts serve as silent reservoirs for transmission of Plasmodium species in the community.

Objective

The aim of this study was to determine the prevalence of API and associated factors among pregnant women. This community-based cross-sectional study was conducted at Merti district, Oromia, Ethiopia among 364 pregnant women from March to September 2018.

Methods

Sociodemographic and obstetrics features were collected using a structured questionnaire. About 2ml of blood was collected from participants to detect Plasmodium species, gametocyte carriage rate, parasite density, and anemia.

Results

The prevalence of API among pregnant women was 3.6%. The proportion of Plasmodium falciparum and Plasmodium vivax was 6(46.2%) and 7(53.8%) respectively. Out of 13 Plasmodium species identified, Gametocyte carriage rate was 4(30.7%). The geometric mean density of the asexual stage of the parasites was 994.7(interquartile [IQR], 320 to 2200) parasites/ul. The geometric mean gametocyte density was 303.3 (interquartile range [IQR], 160 to 600). The proportion of anemia among Plasmodium-infected participants was 12(92.3%). Previous infection by Plasmodium species (AOR = 5.42; 95% CI: 1.19–29.03, p = 0.047), lack of insecticide-treated bed net use (AOR = 6.52; 95% CI: 1.17–36.44, p = 0.032), and living close to stagnant water (AOR = 4.18; 95% CI (1.12–17.36, p = 0.049) were significantly associated with API. Anemia was significantly higher among Plasmodium-infected than non-infected pregnant women (x2 = 27.62, p <0.001).

Conclusion

In the current study, a relatively high prevalence of API was detected among pregnant women. Identifying API in the community is important to prevent the unwanted outcomes of Plasmodium infection and its transmission.
Method-oriented systematic review on the simple scale for acceptance measurement in advanced transport telematics
Authors: Zoellick Jan C. , Kuhlmey Adelheid , Schenk Liane , Blüher Stefan
Published: March 2021

Acceptance intuitively is a precondition for the adaptation and use of technology. In this systematic review, we examine academic literature on the “simple scale for acceptance measurement” provided by Van der Laan, Heino, and de Waard (1997). This measure is increasingly applied in research on mobility systems without having been thoroughly analysed. This article aims to provide such a critical analysis. We identified 437 unique references in three aggregated databases and included 128 articles (N = 6,058 participants) that empirically applied the scale in this review. The typical study focused on a mobility system using a within-subjects design in a driving simulator in Europe. Based on quality indicators of transparent study aim, group allocation procedure, variable definitions, sample characteristics, (statistical) control of confounders, reproducibility, and reporting of incomplete data and test performance, many of the 128 articles exhibited room for improvements (44% below.50; range 0 to 1). Twenty-eight studies (22%) reported reliability coefficients providing evidence that the scale and its sub-scales produce reliable results (median Cronbach’s α >.83). Missing data from the majority of studies limits this conclusion. Only 2 out of 10 factor analyses replicated the proposed two-dimensional structure questioning the use of these sub-scales. Correlation results provide evidence for convergent validity of acceptance, usefulness, and satisfying with limited confidence, since only 14 studies with a median sample size of N = 40 reported correlation coefficients. With these results, the scale might be a valuable addition for technology attitude research. Firstly, we recommend thorough testing for a better understanding of acceptance, usefulness, and satisfying. Secondly, we suggest to report scale results more transparently and rigorously to enable meta-analyses in the future. The study protocol is available at the Open Science Framework (https://osf.io/j782c/).
Metagenomic analysis exploring taxonomic and functional diversity of bacterial communities of a Himalayan urban fresh water lake
Authors: Ahmad Tawseef , Gupta Gaganjot , Sharma Anshula , Kaur Baljinder , El-Sheikh Mohamed A. , Alyemeni Mohammed Nasser
Published: March 2021

Freshwater lakes present an ecological border between humans and a variety of host organisms. The present study was designed to evaluate the microbiota composition and distribution in Dal Lake at Srinagar, India. The non-chimeric sequence reads were classified taxonomically into 49 phyla, 114 classes, 185 orders, 244 families and 384 genera. Proteobacteria was found to be the most abundant bacterial phylum in all the four samples. The highest number of observed species was found to be 3097 in sample taken from least populated area during summer (LPS) whereas the summer sample from highly populated area (HPS) was found most diverse among all as indicated by taxonomic diversity analysis. The QIIME output files were used for PICRUSt analysis to assign functional attributes. The samples exhibited a significant difference in their microbial community composition and structure. Comparative analysis of functional pathways indicated that the anthropogenic activities in populated areas and higher summer temperature, both decrease functional potential of the Lake microbiota. This is probably the first study to demonstrate the comparative taxonomic diversity and functional composition of an urban freshwater lake amid its highly populated and least populated areas during two extreme seasons (winter and summer).