bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of thrombin generation in horses using a calibrated automated thrombogram
Authors: Leclere Mathilde , Chevalier Zoé , Dubuc Valérie , Beauchamp Guy , Bédard Christian
Published: February 2022

Background

The amount of thrombin generated reflects the endogenous thrombin potential (ETP), which depends on the balance of pro‐ and anticoagulant factors. The calibrated automated thrombogram (CAT) allows for the direct measurement of thrombin generation during the clotting process.

Objectives

(1) To describe the results of the CAT assay in horses, (2) to establish intra‐assay and intra‐ and interindividual variation of thrombin generation in healthy horses, and (3) to compare in vitro low‐molecular‐weight heparin (LMWH) sensitivity between healthy and sick horses. The hypothesis for the last objective is that inhibition of thrombin generation in sick horses requires higher heparin concentrations.

Methods

The plasma of 10 healthy mixed breed horses was used for the determination of normal thrombin generation parameters (lag time, time to peak, peak thrombin concentration, and ETP). Five of the healthy horses were compared with five horses with systemic inflammatory response syndrome (SIRS). In vitro heparin sensitivity was determined using LMWH.

Results

The intra‐assay variation was small (<5%) for all parameters. Relatively large intra‐ and interindividual variation were observed in healthy horses. Four of the five sick horses with SIRS had a thrombogram compatible with a hypercoagulable state. The in vitro heparin sensitivity test suggested decreased sensitivity to LMWH in hypercoagulable states.

Conclusions

The CAT assay could detect coagulopathy in horses. In vivo experiments are needed to confirm that it can be used to monitor responses to LMWH therapy.
Comparison of the qualitative and quantitative optical coherence tomographic features between sudden acquired retinal degeneration syndrome and normal eyes in dogs
Authors: Cho Heejong , Jeong Manbok , Lee Songhui , Yoo Sukjong
Published: February 2022

Objective

To quantitatively and qualitatively characterize the retinal optical coherence tomographic features of sudden acquired retinal degeneration syndrome (SARDS) and SARDS suspect dogs.

Animals studied

Fourteen SARDS affected dogs, 11 age‐, breed‐, and sex‐matched control dogs, and two SARDS suspect dogs.

Procedures

Spectral‐domain optical coherence tomography (OCT) images were used to evaluate the quantitative features, including thickness, intereye asymmetry, and longitudinal changes in retinal layer thickness and the qualitative features, including retinal architecture and vitreous haze.

Results

Mean outer retinal layer thickness (ORT), outer nuclear layer thickness (ONL), and photoreceptor layer thickness (PRL) were significantly lower in the SARDS group, whereas mean inner retinal layer thickness was significantly higher in the SARDS group than in the control group. While thickness values of all retinal layers did not differ significantly between paired eyes in each group, the absolute intereye asymmetries in the ORT (p < .0001), ONL (p = .008), and PRL (p < .0001) were significantly higher in the SARDS group than in the control group. Some SARDS patients and SARDS suspects had a greater PRL than the control group, and serial OCT evaluation showed an increase in PRL in one SARDS suspect. Vitreous haze severity was greater in the SARDS group than in the control group (vitreous relative intensity,p = .030).

Conclusions

We described the OCT features of SARDS patients and suspects. In particular, PRL thickening in the SARDS suspects might indicate an early change in SARDS. Although further studies are needed, this finding might provide new insights into the pathogenesis of SARDS.
Evaluation of contraction of the split‐thickness skin graft using three dermal matrices in the treatment of burn contractures: A randomised clinical trial
Authors: Corrêa Fernanda B. , Castro Júlio C. D. , Almeida Ivan R. , Farina‐Junior Jayme A. , Coltro Pedro S.
Published: February 2022

Burn injuries commonly result in serious sequelae (such as skin contractures) in surviving patients, for which no single optimal solution is known. The goal of this study was to compare the late contraction of autologous skin grafts with or without dermal matrices used in the treatment of patients with burn contractures. This parallel design prospective, randomised and controlled clinical trial included patients with burn contracture treated using autologous skin grafts and dermal matrix. Patients were randomly assigned to one of the four groups: Integra® matrix (n = 10), Pelnac® matrix (n = 10), Matriderm® matrix (n = 9) or a Control Group (n = 10, without dermal matrix, only skin graft). The boundaries of skin defect were marked and transferred to a flat sterile surface for area measurement. The current area of the skin grafts was measured during surgery and compared with those obtained at 1, 3, 6 and 12 months postoperatively. Twelve months after surgery, the Control Group presented lower rates of skin graft contraction than Integra® (p < 0.01), Matriderm® (p = 0.01) and Pelnac® (p < 0.01) groups. Pelnac® resulted in larger skin graft contraction than Matriderm® (p < 0.01) and Integra® (p = 0.02), while differences between Integra® and Matriderm® were not significant (p = 0.16). The comparison between intraoperative and 12 months after surgery showed that the worst mean rates of skin graft contraction were from the Pelnac® (51.79%) and Matriderm® (59.17%). In patients with burn contractures, the use of these three dermal matrices did not reduce or avoid the occurrence of late contraction of the skin graft, so their use for this purpose should be carefully evaluated.
Molecular confirmation of Rickettsia parkeri in humans from Southern Mexico
Authors: Torres‐Castro Marco , Sánchez‐Montes Sokani , Colunga‐Salas Pablo , Noh‐Pech Henry , Reyes‐Novelo Enrique , Rodríguez‐Vivas Roger I.
Published: February 2022

Human tick‐borne rickettsioses are caused by Rickettsia africae, Rickettsia massiliae, Rickettsia parkeri, Rickettsia philipi and Rickettsia rickettsii in the American continent. Rickettsia parkeri represents the second most important agent of eschar‐associated spotted fever throughout the American continent. In Mexico, the presence of three strains of this bacterium (Black Gap, Maculatum and Atlantic Rainforest) has recently been reported in four species of ticks from five states (Baja California, Campeche, Sonora, Tabasco and Veracruz) and rickettsaemia was demonstrated in a dog from the state of Yucatán. We report two human cases of R. parkeri‐rickettsiosis from Yucatan, Mexico. These findings have increased the interest in R. parkeri surveillance in the human population, due to the fluctuating regional Spotted Fever morbidity and mortality in the country.
ENRICHMENT OF GRAIN HYDROLYSATE WITH BACTERIAL PROTEIN
Authors: Kiribayeva A.K. , Silayev D.V. , Baduanova S.D. , Khassenov B.B.
Published: February 2022

Feed enrichment with valuable nutrients for animals is a priority for the agricultural industry of Kazakhstan. This paper presents the technology of grain processing into feed preparation using lactic acid bacteria. Enzymatically hydrolyzed grain was a growing medium for the growth of lactic acid bacteria of the genus Lactobacillus. Cultivation of L.plantarum and L.salivarius bacteria in the saccharified grain hydrolysate helped to increase the total protein content in preparations by 26-45% and the enrichment of the feed preparation with glucose, lactic acid, and vitamins. This technology of grain processing into the feed preparation would be useful in terms of deep processing of grain and obtaining feed preparations containing important nutrient ingredients.
MICROPROPAGATION FOR THE CONSERVATION OF RARE AND ENDANGERED MALUS NIEDZWETZKYANA
Authors: Nurtaza A.S. , Magzumova G.K. , Yessimseitova A.K. , Dyussembekova D.A. , Baktybay B. , Turganbayeva A.K. , Kakimzhanova A.A.
Published: February 2022

The conservation of biological diversity is one of the most important tasks at present given the strong association of biodiversity with food security and improving nutrition. Currently, 387 plant species are listed in the Red Book of Kazakhstan, including the rare, endemic, and endangered species Malus niedzwetzkyana, which is also included on the International Red List. Biotechnology methods are currently widely applied to preserve such rare plant species, which allows for the long-term preservation of genetic material, enabling their large-scale reproduction and propagation. One of the most effective methods for this purpose is microclonal propagation, which is similar to the vegetative method of reproduction except that the entire process proceeds with an in vitro culture system. The resulting clones are healthy and genetically stable. In this study, we optimized the microclonal propagation technique for Malus niedzwetzkyana. Axillary buds of annual shoots were used as the initial material. The mode of sterilization of the axillary buds, composition of the nutrient medium for establishment of in vitro culture, and the multiplication and rooting of microshoots were optimized. The data obtained provide an essential resource for sustaining the reproduction and propagation of this rare and endangered species of apple trees.
BIOLOGY, EPIDEMIOLOGY, GENETIC CHARACTERISTICS, AND RESEARCH PRIORITIES OF WEST NILE VIRUS
Authors: Bissenbay A.O. , Zhigailov A.V. , Neupokoyeva A.S. , Naizabayeva D.A. , Skiba Y.A. , Dmitrovskiy A.M. , Shapiyeva Zh.Zh.
Published: February 2022

West Nile fever (WNF) is an acute viral, natural foci infectious disease with a zoonotic mechanism of transmission. WNF has a high incidence in countries with a temperate climate in the summer-fall season. The causative agent is West Nile virus (WNV), which belongs to the Flavivirus genus of the Flaviviridae family. WNV was first isolated in the West Nile district of Uganda in 1937 from the blood of a native Ugandan woman. Several sporadic cases were then reported in Israel, Egypt, India, France, and South Africa from the 1950s to 1980s. However, WNV became a global public health concern after introduction of the virus in New York in 1999, which consequently led to its massive spillover across almost all of the United States, Canada, and Central America. In the 1990s, several significant outbreaks of WNF also occurred in Russia. The virus currently circulates in almost all countries of the African continent, Asia (mainly on the Hindustan subcontinent), Israel, and Europe. In Kazakhstan, WNF cases have mainly been reported in territories bordering Russia and in some areas of the Turkestan oblast. Birds serve as amplifier hosts, and mosquitoes, mainly of the genus Culex, are the primary vectors. Human and horses are the dead-end hosts of the virus. The clinical manifestations of WNV infection in humans range from asymptomatic illness to encephalitis, leading to various neurodegenerative diseases. This article reviews current data on the biology, epidemiology, ecology, geographical distribution, virology, pathology, structure, and genome characteristics of WNV, as well as the main laboratory diagnosis methods and further research priorities.
GENERATION OF THREE-DIMENSIONAL SPHEROIDS FROM MOUSE MESENCHYMAL STEM CELL
Authors: Sekenova A.Y. , Rakhymzhanova A.K. , Li E.A. , Ogay V.B.
Published: February 2022

In comparison with two-dimensional (2D) culture, three-dimensional (3D) cultures of mesenchymal stem cells (MSCs) in spheroids (3D spheroids) offer a more physiologically realistic condition. Accordingly, 3D culture has been used to improve the immunomodulatory properties of MSCs and their survival after transplantation. Several methods have been developed to generate 3D spheroids of MSCs to date; however, these methods are time-consuming or expensive, thus limiting their wide application. In this study, we compared two inexpensive and simple culture methods for the generation of 3D spheroids from the MSCs of mouse compact bone: pellet culture and rotating vessels using low-binding 96-well plates. The  effectiveness of the two methods was determined by the number of obtained spheroids, their diameter, and the expression of the MSC marker CD44 using morphometric and immunofluorescent methods. A higher number of homogeneous 3D spheroids was obtained from the MSCs of compact bone using a rotating vessel compared to that obtained with pellet culture. The immunofluorescence assay further showed that the developed 3D spheroids highly expressed CD44 on the cell surface. Thus, we suggest that the method of rotating vessels is effective for generating 3D spheroids from the MSCs of compact bone. This method can be used to promote research on the biology of stem cells and develop new therapeutic approaches in cell therapy and regenerative medicine.
TRANSFORMATION PRODUCTS AND MICROBIOLOGICAL ACTIVITY OF ANTIBACTERIAL DRUGS ASSESSED IN ANIMAL MODELS
Authors: Ibragimova N.А , Lyu М.B. , Jumabayeva S.M. , Karzhaubayeva R.A. , Sabitov А.N. , Adambekov D.
Published: February 2022

Transformed drugs can exhibit a wide range of new toxicological effects compared to those of their original compounds. Conventional wastewater treatment technologies are only able to partially remove many pharmaceutical preparations and their metabolites from the environment, if at all, resulting in their accumulation in soils and agricultural products. These compounds can then enter the human body via the food chain, which contributes greater selection for resistance of microorganisms to these drugs. In this study, we investigated the biotransformation of ciprofloxacin, metronidazole, and adduct iodine in rats. The sensitivity of Staphylococcus aureus, Enterococcus faecalis, and Escherichia coli strains to the used drugs was then determined in vitro and in vivo in a mouse model of sepsis. Ciprofloxacin, metronidazole, and iodine adduct biotransformation products were all detected in the urine and feces of rats during the 7-day course of application. The highest concentrations of ciprofloxacin and metronidazole were found in the urine, whereas the highest concentration of iodides was detected in the feces. In vitro studies showed that all three strains were sensitive to the test drugs. Treatment of mice with metronidazole, ciprofloxacin, and iodine adduct caused positive dynamics of the septicopyemia course, but resulted in the development of resistance to metronidazole. These results highlight the necessity to include detection of biotransformed pharmaceutical preparations and their metabolites in open water sources as part of routine monitoring programs of the Republic of Kazakhstan.
Archipiélago juvenil: jóvenes indígenas y cultura digital
Authors: Meneses Cárdenas Jorge Alberto
Published: February 2022

El artículo se enfoca en la cultura digital de jóvenes universitarios indígenas en México y Colombia. A través de una etnografía digital multisituada, presento un mosaico de prácticas y saberes juveniles derivadas de sus experiencias sociodigitales. El tránsito por distintas islas de socialidad me permitió conocer sus saberes, tanto en sus intercambios cara a cara como en la plataforma Facebook. Lejos de pensar que la vida digital está aislada de los microcontextos, los distintos flujos de sentido y las prácticas son resultado de la imbricación entre lo presencial y la copresencia digital. Por esa razón, utilicé herramientas híbridas con el objetivo de ubicar los flujos de sus culturas digitales. Metafóricamente, se puede afirmar que los jóvenes habitan un archipiélago juvenil desde donde se conectan a sus muros para alojar y dinamizar hipernarrativas. Precisamente, los resultados muestran trayectorias biográficas desiguales, y repertorios y prácticas sociodigitales con saberes multirreferenciales.
Mapeo de actores en la Costa Caribe norte de Nicaragua: un análisis según el género y la identificación étnica y cultural
Authors: Cupples Julie , Incer Medina Guillermo , Larios Irving , Lee Smith Dixie
Published: February 2022

Este artículo se deriva de un estudio en dos municipios de la Costa Caribe norte de Nicaragua, que interactúa de manera crítica con la agenda de investigación británica, dominante en este momento. Mediante un stakeholder analysis, hemos intentado mapear el poder cultural en esta parte de Nicaragua en un contexto de racismo persistente, desigualdad de género, pobreza, destrucción ambiental y creciente autoritarismo político mediante entrevistas, grupos focales y talleres con actores relevantes. La investigación fue realizada por un grupo de académicos, profesionales de una organización no gubernamental (ONG) y activistas de la sociedad civil que viven en la costa o que tienen una participación política y profesional a largo plazo, en la región. Proporciona un conjunto de recomendaciones para los organismos gubernamentales y las organizaciones de la sociedad civil, con potencial de aumentar el impacto positivo de nuestros proyectos de investigación y desarrollo en la región.
Ya me miro al espejo, ya no me echo culpas, ya quiero ser otra”: memoria, cuerpos y violencia en el departamento del Meta, Colombia*
Authors: Chaparro Hurtado Hector Rolando , González Ulloa Elkin
Published: February 2022

El artículo presenta el resultado del proyecto de investigación “La voz como persuasión: cuerpo, memoria y desplazamiento en producciones narrativas”, financiado institucionalmente en la convocatoria del 2016 de la Universidad de los Llanos. Plantea un análisis sobre las formas de inscripción de los registros de la violencia en el cuerpo de las personas que han sido víctimas de la violencia en el departamento del Meta. En este contexto, en el de los cuerpos atravesados por la(s) violencia(s) sucesivas a nivel nacional y regional, el departamento del Meta se constituye en una de las unidades territoriales que mayor número de desplazamiento forzoso genera y recibe en Colombia. Y aunque las preocupaciones gubernamentales se centran más en su relocalización o en las formas de adaptación a los mundos del empleo y el consumo, poco se ha dicho sobre la memoria de la violencia tejida en la piel, aquella que difícilmente caduca porque está completamente encarnada. Se trata, entonces, de dar la voz a quienes no la han tenido nunca, a quienes desde lo subalterno o desde la intimidad hacen del silencio su refugio y su morada, y a quienes los estudios ocultan como objetos de examen o como informantes calificados para el oído y el análisis de los expertos.
Enduring Edge
Authors: Winters Jeffrey
Published: February 2022

The degree to which technical skills are needed for new graduates and early career engineers is hotly debated. By some standards, deep knowledge of digital engineering technologies has never been more important or so hard to come by. But the difference-makers, employers say, are abilities that might be thought of as “soft skills,” such as flexibility, leadership, innate curiosity, and a flair for innovation.
Design and Cost Study of Improved Scaled-Up Centrifugal Particle Receiver Based on Simulation
Authors: Frantz Cathy , Buck Reiner , Amsbeck Lars
Published: February 2022

A numerical model of the CentRec® receiver has been developed and validated using the measurement data collected during the experimental test campaign of the centrifugal particle system at the solar tower Jülich. The model has been used to calculate the thermo-optical efficiency of a scaled-up 20 MWth receiver for various receiver geometries. A cost function has been deduced and was used to perform a techno-economic study on an levelized cost of heat (LCOH) basis of the CentRec® receiver concept. Attractive LCOH as low as 0.0209 €/kWhth for a system with thermal storage, or as low as 0.0150 €/kWhth for the LCOH without storage, is predicted. This study has shown that the optimal configuration from an LCOH perspective for a 20 MWth centrifugal particle receiver reaches specific receiver costs of 35 €/kWth. Hereby, the costs of the receiver can be reduced by 60% compared to the original configuration.
The Response of an Inerter-Based Dynamic Vibration Absorber With a Parametrically Excited Centrifugal Pendulum
Authors: Gupta Aakash , Tai Wei-Che
Published: February 2022

The inerter has been integrated into various vibration mitigation devices, whose mass amplification effect could enhance the suppression capabilities of these devices. In the current study, the inerter is integrated with a pendulum vibration absorber, referred to as inerter pendulum vibration absorber (IPVA). To demonstrate its efficacy, the IPVA is integrated with a linear, harmonically forced oscillator seeking vibration mitigation. A theoretical investigation is conducted to understand the nonlinear response of the IPVA. It is shown that the IPVA operates based on a nonlinear energy transfer phenomenon wherein the energy of the linear oscillator transfers to the pendulum vibration absorber as a result of parametric resonance of the pendulum. The parametric instability is predicted by the harmonic balance method along with the Floquet theory. A perturbation analysis shows that a pitchfork bifurcation and period doubling bifurcation are necessary and sufficient conditions for the parametric resonance to occur. An arc-length continuation scheme is used to predict the boundary of parametric instability in the parameter space and verify the perturbation analysis. The effects of various system parameters on the parametric instability are examined. Finally, the IPVA is compared with a linear benchmark and an autoparametric vibration absorber and shows more efficacious vibration suppression.
Multimodal Data-Driven Robot Control for Human–Robot Collaborative Assembly
Authors: Liu Sichao , Wang Lihui , Vincent Wang Xi
Published: February 2022

In human–robot collaborative assembly, leveraging multimodal commands for intuitive robot control remains a challenge from command translation to efficient collaborative operations. This article investigates multimodal data-driven robot control for human–robot collaborative assembly. Leveraging function blocks, a programming-free human–robot interface is designed to fuse multimodal human commands that accurately trigger defined robot control modalities. Deep learning is explored to develop a command classification system for low-latency and high-accuracy robot control, in which a spatial-temporal graph convolutional network is developed for a reliable and accurate translation of brainwave command phrases into robot commands. Then, multimodal data-driven high-level robot control during assembly is facilitated by the use of event-driven function blocks. The high-level commands serve as triggering events to algorithms execution of fine robot manipulation and assembly feature-based collaborative assembly. Finally, a partial car engine assembly deployed to a robot team is chosen as a case study to demonstrate the effectiveness of the developed system.
Co-Evolution of Communication and System Performance in Engineering Systems Design: A Stochastic Network-Behavior Dynamics Model
Authors: Chaudhari Ashish M. , Gralla Erica L. , Szajnfarber Zoe , Panchal Jitesh H.
Published: February 2022

Engineering systems design is a dynamic socio-technical process where the social factors, such as interdisciplinary interactions, and technical factors, such as design interdependence and the design state, co-evolve. Understanding this co-evolution can lead to behavioral insights, resulting in efficient communication pathways and better designs. In that context, we investigate how to generate behavioral insights to inform effective structuring of interdisciplinary interactions in engineering systems design teams. We present an approach that combines the predictive capabilities of computational modeling with contextual information from empirical data. A stochastic network-behavior dynamics model quantifies the co-evolution of design interdependence, discipline-specific interaction decisions, and the changes in system performance. We employ two datasets, one of the student subjects designing an automotive engine and NASA engineers designing a spacecraft. Then, we apply Bayesian statistical inference to estimate model parameters and compare insights across the two datasets. The results indicate that design interdependence and social network factors such as reciprocity and popularity have strong positive effects on interdisciplinary interactions for the expert and student subjects alike. An additional modulating impact of system performance on the number of interactions is observed for the student subjects. Inversely, the total number of interactions, irrespective of their discipline-wise distribution, has a weak but statistically significant positive effect on system performance in both cases. However, we observe that excessive interactions mirrored with design interdependence and inflexibility in design exploration reduced the system performance. These insights support the case for open boundaries in systems design teams to improve system performance.
Geometric Error Propagation Model-Based Accuracy Synthesis and Its Application to a 1T2R Parallel Manipulator
Authors: Tang Tengfei , Chi Changcheng , Fang Hanliang , Zhang Jun
Published: February 2022

To meet the increasing requirements for precision hybrid machine tools, this paper presents a geometric error propagation model-based accuracy synthesis method for parallel manipulators (PMs) with one translational and two rotational (1T2R) motion abilities. A unified geometric error propagation model of a family of 1T2R PMs is established with the first-order kinematic perturbation method. A set of geometric error propagation intensity indexes is formulated to describe the geometric error propagation characteristics in a quantitative manner. The equivalent effects of specified terminal accuracy are derived to directly determine the allowable values of all geometric source errors. Based on these, a computation algorithm is summarized for designating a tolerance allocation scheme to meet the specified terminal accuracy of a 1T2R PM. To demonstrate the accuracy synthesis method, a novel 1T2R PM with a 2UPR-1RPS (“R,” revolute joint; “U,” universal joint; “S,” spherical joint; “P,” prismatic actuated joint) topology is taken as an example to allocate geometric tolerances under the specified terminal accuracy. Following the tolerance allocation scheme, a laboratory prototype of the exemplary PM is fabricated and further experimentally measured. The measured kinematic results indicate that the prototype possesses an acceptable position error smaller than 0.15 mm, verifying the feasibility of the proposed accuracy synthesis method. Hence, the proposed method can be applied as a forward tolerance design tool to reduce the design iterations and development risks of low-mobility parallel robots.
Efficient Model-Free Calibration of a 5-Degree of Freedom Hybrid Robot
Authors: Shen NanYan , Yuan HengMing , Li Jing , Wang ZiRui , Geng Liang , Shi HuiEn , Lu NingHe
Published: February 2022

The pose accuracy is a crucial issue that limits the application of hybrid robots. The model-free calibration instead of complex error modeling is investigated to improve the pose accuracy of a 5-degrees-of-freedom (DOF) hybrid robot efficiently. To overcome the difficult problem of model-free calibration in high-dimension joint space that the required measurement data for accurate prediction increase exponentially, a dimensionality reduction method is proposed to decompose high-dimension joint space into two low-dimension subspaces. Then the pose errors can be respectively measured in two subspaces based on the calibrated standard poses to train their corresponding pose error predicators. The standard poses ensure the measured pose errors in two subspaces do not affect each other. Thus, a merging operation obtained by kinematic analysis can finally merge the predicted pose errors of two subspaces into the complete pose error. The error predicators established by several regression methods including artificial neural network, extreme learning machine (ELM) and Twin Gaussian process regression are compared on multi aspects, and ELM stands out among them due to its outstanding prediction accuracy, good anti-noise ability, and low training data requirements. In addition, different representations of pose and pose error are adopted at different calibration stages to deal with the influence of parasitic motion of hybrid robot for the implementation of proposed calibration method. The compensation experiment is executed and the results show that position and orientation errors are reduced by 92.4% and 88.2% on average after calibration and the pose accuracy can meet application requirements.
Y recombination arrest and degeneration in the absence of sexual dimorphism
Authors: Lenormand Thomas , Roze Denis
Published: February 2022

Current theory proposes that degenerated sex chromosomes—such as the mammalian Y—evolve through three steps: (i) recombination arrest, linking male-beneficial alleles to the Y chromosome; (ii) Y degeneration, resulting from the inefficacy of selection in the absence of recombination; and (iii) dosage compensation, correcting the resulting low expression of X-linked genes in males. We investigate a model of sex chromosome evolution that incorporates the coevolution of cis and trans regulators of gene expression. We show that the early emergence of dosage compensation favors the maintenance of Y-linked inversions by creating sex-antagonistic regulatory effects. This is followed by degeneration of these nonrecombining inversions caused by regulatory divergence between the X and Y chromosomes. In contrast to current theory, the whole process occurs without any selective pressure related to sexual dimorphism.
Geometry of sequence working memory in macaque prefrontal cortex
Authors: Xie Yang , Hu Peiyao , Li Junru , Chen Jingwen , Song Weibin , Wang Xiao-Jing , Yang Tianming , Dehaene Stanislas , Tang Shiming , Min Bin , Wang Liping
Published: February 2022

How the brain stores a sequence in memory remains largely unknown. We investigated the neural code underlying sequence working memory using two-photon calcium imaging to record thousands of neurons in the prefrontal cortex of macaque monkeys memorizing and then reproducing a sequence of locations after a delay. We discovered a regular geometrical organization: The high-dimensional neural state space during the delay could be decomposed into a sum of low-dimensional subspaces, each storing the spatial location at a given ordinal rank, which could be generalized to novel sequences and explain monkey behavior. The rank subspaces were distributed across large overlapping neural groups, and the integration of ordinal and spatial information occurred at the collective level rather than within single neurons. Thus, a simple representational geometry underlies sequence working memory.
Remote steric control for undirected
meta
-selective C–H activation of arenes
Authors: Ramadoss Boobalan , Jin Yushu , Asako Sobi , Ilies Laurean
Published: February 2022

Regioselective functionalization of arenes remains a challenging problem in organic synthesis. Steric interactions are often used to block sites adjacent to a given substituent, but they do not distinguish the remaining remote sites. We report a strategy based on remote steric control, whereby a roof-like ligand protects the distant
para
site in addition to the
ortho
sites, and thereby enables selective activation of
meta
carbon-hydrogen (C–H) bonds in the absence of
ortho
or
para
substituents. We demonstrate this concept for iridium-catalyzed
meta
-selective borylation of various monosubstituted arenes, including complex drug molecules. This strategy has the potential to expand the toolbox of C–H bond functionalization to previously nondifferentiable reaction sites.
Complete Genome Sequences of Four Isolated Bacteria from an Undergraduate Microbiology Course Using a Hybrid Assembly Approach
Authors: Sanders Ciara I. , Ne Ville Christopher J. , Orwin Paul M.
Published: February 2022

Three Gram-negative bacteria and one Gram-positive bacterium were isolated from environmental samples in an undergraduate microbiology class on the basis of antibiotic resistance. Isolate DNA was purified, sequenced, and assembled using a hybrid approach. Here, we report the genomes of
Acinetobacter johnsonii
CSUSB1,
Aeromonas hydrophila
CSUSB2,
Bacillus velezensis
CSUSB3, and
Comamonas thiooxydans
CSUSB4.
Draft Genome Sequences of Two
Streptomyces
Isolates Obtained from Volcanic Soils in the Philippines
Authors: Marasigan Rey Vladimir , Alcantara Edwin , Pangilinan Elcid Aaron , Tablizo Francis , Morado El King , Araiza Shiela Mae , Punayan Kris , Maralit Benedict , Bautista Ma. Anita
Published: February 2022

We report here the draft genome sequences of two
Streptomyces
isolates, namely, UNOB3_S3 and UNOC14_S4, obtained from volcanic soils in Albay, Philippines. The genome assemblies comprised 7.63 Mb and 8.24 Mb, respectively. Genome mining revealed genes and biosynthetic gene clusters that encode putative insecticidal products.
Draft Genome Sequences of Four Strains of Campylobacter jejuni Isolated from Patients with Axonal Variant of Guillain-Barré Syndrome in Bangladesh
Authors: Hayat Shoma , Nabila Fahmida Habib , Asad Asaduzzaman , Begum Ruma , Jahan Israt , Endtz Hubert P. , Islam Zhahirul
Published: February 2022

Four
Campylobacter jejuni
strains (Z191005RS, Z191005SS, Z201020RS, and Z201020SS) isolated from the axonal variant of Guillain-Barré syndrome (GBS) were sequenced using Illumina technology. The average genome size was from 1.61 to 1.63 gb, with a very high coverage ranging from 654× to 758×, which facilitates the possibility of rare variant calling.
Complete Genome Sequences of Two Bovine Alphaherpesvirus 5 Subtype C Strains from Southeast Brazil
Authors: Paim Willian P. , Campos Fabrício S. , Cibulski Samuel P. , Scheffer Camila M. , Tochetto Caroline , Varela Ana P. M. , Junqueira Dennis M. , Mayer Fabiana Q. , Romijn Phyllis C. , Pituco Edviges M. , Franco Ana C. , Spilki Fernando R. , Roehe Paulo M.
Published: February 2022

Bovine alphaherpesvirus 5 causes meningoencephalitis in cattle, belongs to the
Herpesviridae
family, and can be divided into subtypes a, b, and c. Limited information is available about subtype c. Here, we report the complete genome sequences of two strains, P160/96, and ISO97/45, isolated from cattle in southeast Brazil.
The stability of dinosaur communities before the Cretaceous–Paleogene (K–Pg) boundary: A perspective from southern Alberta using calcium isotopes as a dietary proxy
Authors: Martin Jeremy E. , Hassler Auguste , Montagnac Gilles , Therrien François , Balter Vincent
Published: February 2022

Reconstructing dinosaur trophic structure prior to the Cretaceous–Paleogene (K–Pg) boundary may provide information about ecosystem organization and evolution. Using calcium isotopes, we investigate preserved biogenic isotope compositions in a set of dinosaur teeth from three continental formations from Alberta, Canada, to assess latest Cretaceous food web structure. Tooth enamel δ44/42Ca values are presented for tyrannosaurids (n = 34) and potential large herbivorous prey (n = 42) in the upper Campanian Dinosaur Provincial Park Formation, upper-most Campanian–Maastrichtian Horseshoe Canyon Formation, and upper Maastrichtian–lower Paleocene Scollard Formation, spanning the last ~10 m.y. of the Cretaceous. The influence of diagenesis is assessed in a subset sample through major and trace elemental concentrations and ultraviolet (UV) Raman spectra, which provides a framework for interpreting calcium isotope values. In the Dinosaur Park Formation, hadrosaurid δ44/42Ca values are systematically heavier than ceratopsid values, a difference that is interpreted to reflect niche partitioning among megaherbivores. Tyrannosaurid δ44/42Ca values are scattered but on average, they are 44Ca-depleted relative to herbivorous dinosaurs in all three formations. As interpreted from the Dinosaur Park data set, tyrannosaurids may have preferentially fed on hadrosaurids. These analyses offer possibilities for testing whether trophic structure among non-avian dinosaur ecosystems changed several millions of years prior to the K–Pg boundary.
Management of neck of femur fracture in an adult with short stature and learning disability
Authors: Gandbhir Viraj , Ramavath Ashok , Rajpura Asim
Published: February 2022

Neck of femur fractures (NOFF) are one of the major health concerns, with their incidence and the cost of care rising each year. Though a plethora of literature remains available on NOFF and its management, we found very little evidence for management of NOFF in patients with short stature and learning disability. Because of this unique combination of conditions in our patient, we had to deviate from the standard practice in terms of the implant choice. The usage of cemented Asian C stem AMT with a 36 mm metallic head which is normally reserved for total hip replacements, helped us obtain the desired hip joint stability. This was supplemented by early involvement of the learning disability physiotherapy team and eventually the patient had a satisfactory outcome at 8 months of follow-up. This rare amalgamation of NOFF, short stature and learning disability deserves more attention which our case report hopes to achieve.
Successful rescue from kidney failure with delayed catheter-directed intervention after catastrophic bilateral kidney paradoxical thromboembolism
Authors: Lim Jing Loong , Lau Kenneth K , Lim Andy K H
Published: February 2022

A 62-year-old man presented with acute abdominal and flank pain, oligoanuria and severe acute kidney injury. Unenhanced CT imaging did not detect urolithiasis or hydronephrosis. There was an early blood pressure surge followed by an intense inflammatory response, with a rise in peripheral blood leucocytes and C reactive protein. His urinalysis was bland but the serum lactate dehydrogenase was markedly elevated. CT angiograms demonstrated multiple pulmonary emboli and bilateral renal artery thromboembolism, with occlusion of the left main renal artery. Despite an 88-hour delay from pain onset, catheter-directed thrombolysis and thromboaspiration of both renal arteries were successfully performed, allowing the patient to recover enough kidney function to cease haemodialysis. A patent foramen ovale with right-to-left shunting was discovered, and paradoxical embolism was suspected as the cause of renal infarction. The benefit of catheter-directed reperfusion after prolonged bilateral renal ischaemia is not easily predicted by the severity or duration of acute kidney injury alone.
Ocular adverse events associated with chimeric antigen receptor T-cell therapy: a case series and review
Authors: Mumtaz Aisha A , Fischer Andrew , Lutfi Forat , Matsumoto Lisa R , Atanackovic Djordje , Kolanci Elif T , Hankey Kim G , Hardy Nancy M , Yared Jean A , Kocoglu Mehmet H , Rapoport Aaron P , Dahiya Saurabh , Li Albert S , Sunshine Sarah Brem
Published: February 2022

Background/aims

Chimeric antigen receptor T-cell (CAR T) therapy has been shown to improve the remission rate and survival for patients with refractory haematological malignancies. The aim of this study is to describe ocular adverse effects associated with CAR T therapy in patients with haematological malignancies.

Methods

This is a retrospective, single-institution, case series. Patients aged 18 years or older who received standard of care CAR T therapy for relapsed/refractory large B-cell lymphoma with a documented ophthalmic evaluation were included. The primary outcome was clinician ophthalmic examination findings.

Results

A total of 66 patients received CAR T-cell therapy from February 2018 to October 2019 with 11 receiving an ophthalmic examination. Eleven patients (n=22 eyes) who received CAR T-cell therapy were included in review. The median time from CAR T-cell infusion date to ocular examination was 57.5 days. The median patient age at the time of examination was 60.5 years. Ten patients had subjective symptoms prompting ophthalmic examination. Two patients reported floaters and photopsias. One patient had worsening ocular graft-versus-host disease. Two patients were identified with possible reactivation of viral infections, including herpes zoster ophthalmicus and regressing acute retinal necrosis.

Conclusions

The increasing use of CAR T therapy for malignancies underscores the importance of ophthalmologists and oncologists understanding the potential toxicities associated with its use, particularly ocular toxicities and when to refer for an ophthalmic examination.
Study protocol for a randomised trial evaluating the non-inferiority of stepped palliative care versus early integrated palliative care for patients with advanced lung cancer
Authors: Post Kathryn E , Heuer Lauren B , Kamal Arif H , Kumar Pallavi , Elyze Madeleine , Griffith Sarah , Han Jacqueline , Friedman Fred , Jackson Ashley , Trotter Chardria , Plotke Rachel , Vyas Charu , Jackson Vicki , Rabideau Dustin J , Greer Joseph A , Temel Jennifer S
Published: February 2022

Introduction

Integrating palliative care (PC) early in the illness course for patients with serious cancers improves their outcomes and is recommended by national organisations such as the American Society of Clinical Oncology. However, monthly visits with PC clinicians from the time of diagnosis can be challenging to implement due to the lack of specialty-trained PC clinicians and resources. Therefore, we developed a stepped care model to triage PC service based on patients’ needs.

Methods and analysis

We are conducting a non-blinded, randomised trial to evaluate the non-inferiority of a stepped PC model compared with an early integrated PC model for improving patients’ quality of life (QOL) at 24 weeks (primary outcome). Patients assigned to early integrated PC meet with PC every 4 weeks throughout their illness. Patients assigned to stepped PC have PC visits only at clinically significant points in their illness (eg, cancer progression) unless their QOL decreases, at which time they are ‘stepped up’ and meet with PC every 4 weeks throughout the remainder of their illness. Secondary aims include assessing whether stepped PC is non-inferior to early integrated PC regarding patient-clinician communication about end of life care and length of stay on hospice as well as comparing resource utilisation. Patients are recruited from the Massachusetts General Hospital Cancer Center, Boston, Massachusetts; Duke Cancer Center, Durham, North Carolina and University of Pennsylvania Abramson Cancer Center, Philadelphia, Pennsylvania. The target sample size is 510 patients.

Ethics and dissemination

The study is funded by the National Cancer Institute, approved by the Dana-Farber/Harvard Cancer Center Institutional Review Board and will be reported in accordance with the Consolidated Standards of Reporting Trials statement. We will disseminate results through professional society meetings, peer-reviewed publications and presentations to patient organisations.

Trial registration number

NCT03337399.
Prognostic disclosure in oncology - current communication models: a scoping review
Authors: Bloom Julie Rachel , Marshall Deborah Catherine , Rodriguez-Russo Carlos , Martin Emily , Jones Joshua Adam , Dharmarajan Kavita Vyas
Published: February 2022

Background

Prognostic disclosure is essential to informed decision making in oncology, yet many oncologists are unsure how to successfully facilitate this discussion. This scoping review determines what prognostic communication models exist, compares and contrasts these models, and explores the supporting evidence.

Method

A protocol was created for this study using the Preferred Reporting Items for Systematic Reviews and Meta-analyses Protocols extension for Scoping Reviews. Comprehensive literature searches of electronic databases MEDLINE, EMBASE, PsycINFO and Cochrane CENTRAL were executed to identify relevant publications between 1971 and 2020.

Results

In total, 1532 articles were identified, of which 78 met inclusion criteria and contained 5 communication models. Three of these have been validated in randomised controlled trials (the Serious Illness Conversation Guide, the Four Habits Model and the ADAPT acronym) and have demonstrated improved objective communication measures and patient reported outcomes. All three models emphasise the importance of exploring patients’ illness understanding and treatment preferences, communicating prognosis and responding to emotion.

Conclusion

Communicating prognostic estimates is a core competency skill in advanced cancer care. This scoping review highlights available communication models and identifies areas in need of further assessment. Such areas include how to maintain learnt communication skills for lifelong practice, how to assess patient and caregiver understanding during and after these conversations, and how to best scale these protocols at the institutional and national levels.
Thunderclap headache syndrome presenting to the emergency department: an international multicentre observational cohort study
Authors: Roberts Tom , Horner Daniel E , Chu Kevin , Than Martin , Kelly Anne-Maree , Klim Sharon , Kinnear Frances , Keijzers Gerben , Karamercan Mehmet Akif , Wijeratne Tissa , Kamona Sinan , Kuan Win Sen , Graham Colin A , Body Richard , Laribi Said
Published: February 2022

Background

Most headache presentations to emergency departments (ED) have benign causes; however, approximately 10% will have serious pathology. International guidelines recommend that patients describing the onset of headache as ‘thunderclap’ undergo neuroimaging and further investigation. The association of this feature with serious headache cause is unclear. The objective of this study was to determine if patients presenting with thunderclap headache are significantly more likely to have serious underlying pathology than patients with more gradual onset and to determine compliance with guidelines for investigation.

Methods

This was a planned secondary analysis of an international, multicentre, observational study of adult ED patients presenting with a main complaint of headache. Data regarding demographics, investigation strategies and final ED diagnoses were collected. Thunderclap headache was defined as severe headache of immediate or almost immediate onset and peak intensity. Proportion of patients with serious pathology in thunderclap and non-thunderclap groups were compared by χ² test.

Results

644 of 4536 patients presented with thunderclap headache (14.2%). CT brain imaging and lumbar puncture were performed in 62.7% and 10.6% of cases, respectively. Among patients with thunderclap headache, serious pathology was identified in 10.9% (95%CI 8.7% to 13.5%) of cases—significantly higher than the proportion found in patients with a different headache onset (6.6% (95% CI 5.9% to 7.4%), p<0.001.). The incidence of subarachnoid haemorrhage (SAH) was 3.6% (95% CI 2.4% to 5.3%) in those with thunderclap headache vs 0.3% (95% CI 0.2% to 0.5%) in those without (p<0.001). All cases of SAH were diagnosed on CT imaging. Non-serious intracranial pathology was diagnosed in 87.7% of patients with thunderclap headache.

Conclusions

Thunderclap headache presenting to the ED appears be associated with higher risk for serious intracranial pathology, including SAH, although most patients with this type of headache had a benign cause. Neuroimaging rates did not align with international guidelines, suggesting potential need for further work on standardisation.