bluuebunny/crossref_metadata_2025 huggingface dataset:
Tricuspid valve repair concomitant with the Norwood operation among babies with hypoplastic left heart syndrome
Authors: Wamala Isaac , Friedman Kevin G , Saeed Mossab Y , Gauvreau Kimberlee , Gellis Laura , Borisuk Michele , Kaza Aditya , Emani Sitaram , del Nido Pedro J , Baird Christopher W
Published: January 2022

OBJECTIVES

Among patients with hypoplastic left heart syndrome (HLHS), tricuspid valve regurgitation (TR) portends a poor prognosis. Our goal was to describe the outcomes of tricuspid valve reconstruction (TVR) concomitant with the Norwood operation and using two-dimensional echocardiography and evaluate the structural factors associated with successful functional correction.

METHODS

We performed a retrospective, single-centre study of patients with HLHS undergoing TVR at the time of the Norwood operation. Structural echocardiographic parameters were compared between patients with successful correction (≤ mild TR) and those with ≥ moderate regurgitation at discharge. Preoperative dimensions of matched HLHS controls with ≤ trivial TR were used as a reference.

RESULTS

Of 205 patients with HLHS undergoing the Norwood operation, 18 patients had a concomitant TVR. Ten (56%) patients had an improved TR grade postoperatively, 8 (44%) of whom had ≤ mild TR at discharge. Improvement in TR grade (P = 0.001) and having ≤ mild TR at discharge (P = 0.011) were associated with an improved reintervention and TR-free survival. Patients with successful functional correction had smaller preoperative tricuspid annulus lateral dimensions (P = 0.023), tricuspid valve area (P = 0.007) and right ventricle mid-width (P = 0.064). Preoperatively, the successful TVR cases tended to have had higher anterior leaflet excursion (80 ± 20 vs 55 ± 11, P = 0.010), and a higher proportion of anterior leaflet prolapse (63% vs 10%, P = 0.043) compared to cases where TVR was not successful.

CONCLUSIONS

Patients with HLHS with significant tricuspid regurgitation undergoing the stage 1 operation were more likely to have successful concomitant tricuspid valve repair if they had less tricuspid annular dilation, less-severe RV enlargement and predominantly anterior leaflet prolapse. Successful tricuspid valve repair was associated with improved mid- and long-term outcomes.
What Drives Anti-Immigrant Sentiments Online? A Novel Approach Using Twitter
Authors: Menshikova Anastasia , van Tubergen Frank
Published: January 2022

Most studies use survey data to study people’s prejudiced views. In a digitally connected world, research is needed on out-group sentiments expressed online. In this study, we show how one can elaborate on existing sociological theories (i.e. group threat theory, contact theory) to test whether anti-immigrant sentiments expressed on Twitter are related to sociological conditions. We introduce and illustrate a new method of collecting data on online sentiments, creating a panel of 28,000 Twitter users in 39 regions in the United Kingdom. We apply automated text analysis to quantify anti-immigrant sentiments of 500,000 tweets over a 1-year period. In line with group threat theory, we find that people tweet more negatively about immigrants in periods following more salient coverage of immigration in the news. We find this association both for national news coverage, and for the salience of immigration in the personalized set of outlets people follow on Twitter. In support of contact theory, we find evidence to suggest that Twitter users living in areas with more non-western immigrants, and those who follow a more ethnically diverse group of people, tweet less negatively about immigrants.
Understanding the pathways leading to gut dysbiosis and enteric environmental dysfunction in infants: the influence of maternal dysbiosis and other microbiota determinants during early life
Authors: Moya-Alvarez Violeta , Sansonetti Philippe J
Published: January 2022

Maternal environmental enteric dysfunction (EED) encompasses undernutrition with an inflammatory gut profile, a variable degree of dysbiosis and increased translocation of pathogens in the gut mucosa. Even though recent research findings have shed light on the pathological pathways underlying the establishment of the infant gut dysbiosis, evidence on how maternal EED influences the development of gut dysbiosis and EED in the offspring remains elusive. This review summarizes the current knowledge on the effect of maternal dysbiosis and EED on infant health, and explores recent progress in unraveling the mechanisms of acquisition of a dysbiotic gut microbiota in the offspring. In Western communities, maternal inoculum, delivery mode, perinatal antibiotics, feeding practices and infections are the major drivers of the infant gut microbiota during the first 2 years of life. In other latitudes, the infectious burden and maternal malnutrition might introduce further risk factors for infant gut dysbiosis. Novel tools, such as transcriptomics and metabolomics, have become indispensable to analyze the metabolic environment of the infant in utero and postpartum. Human milk oligosaccharides have essential prebiotic, antimicrobial and anti-biofilm properties that might offer additional therapeutic opportunities.
A Chromosome-Level Genome Assembly of the Parasitic Wasp Chelonus formosanus Sonan 1932 (Hymenoptera: Braconidae)
Authors: Liu Jian-Feng , Zhao Hai-Yan , Song Yan-Fei , Yu Yuan-Chan , Yang Mao-Fa
Published: January 2022

Chelonus formosanus Sonan 1932 (Hymenoptera: Braconidae) is a wasp capable of parasitizing a variety of lepidopteran pests at the “egg-larval” stage which distributes throughout Taiwan, Guangdong, Zhejiang, and Hainan provinces of China. This wasp has been successfully used to control pests such as Spodoptera litura Fabricius, 1775, Spodoptera frugiperda (JE Smith, 1797), Spodoptera exigua (Hübner, 1808), and Helicoverpa armigera (Hübner, 1808). So far, there is only one genome assembled from the Chelonus genus [Chelonus insularis (Cresson, 1865)] and it is fragmented with 455 scaffolds. Here, we report a chromosome-level genome assembly of C. formosanus, which was sequenced using PacBio, Illumina, and Hi-C technologies. The long reads were 35.4 Gb (∼150× coverage) with an average length of 15.23 kb. The size of the genome assembly was 139.59 Mb. More than 99.46% of the assembled sequences were anchored to seven pseudochromosomes (138.84 Mb). The Benchmarking University Single-Copy Orthologs (BUSCO) assessment results showed 99.0% of the 1,367 genes (insect_odb10 database) were completely present. We annotated 11,242 protein-coding genes including 98.6% of BUSCO complete genes that were recovered. Nearly one-fourth of the genome assembly (22.25%) was annotated as repetitive sequences and 324 noncoding RNAs were predicted. There were 58 gene families found with significant expansion including allelopathic families (odorant receptors and ionotropic receptors), which may play a crucial role in efficiently locating a wide range of hosts. This high-quality genome assembly and annotation could provide a highly valuable resource of parasitic wasp for the biological control of Lepidoptera pest.
Characteristics of the North Anatolian Fault at the eastern end of Marmara seismic gap based on multidisciplinary field evidence
Authors: Kozacı Özgür , Altunel Erhan
Published: January 2022

The northern branch of the North Anatolian Fault (NAF) is the primary source of the greatest natural hazard for the Marmara Megapolis and specifically the İstanbul Metropolitan area. The Sea of Marmara section of the NAF is a ∼125-km-long seismic gap bound by the M7.4 1912 Mürefte earthquake rupture in the west and M7.4 1999 İzmit earthquake rupture in the east. Terminations of these ruptures define the length of the seismic gap in the Marmara Sea and consequently the magnitude and rupture extent of the expected large magnitude earthquake. The Hersek Peninsula is the last location where the NAF can be studied on land before it enters the Sea of Marmara. In addition, it is a geologically key location for the western termination of the M7.4 İzmit surface rupture. This study integrates high-resolution onshore and offshore data from Hersek Peninsula and its vicinity in İzmit Bay to assess the seismic hazard for the Marmara region. Detailed geological and geomorphic mapping, palaeoseismic trenching, geophysical and geotechnical subsurface data and archeoseismologic investigations demonstrate that the 1999 İzmit earthquake surface rupture died off east of the Hersek Peninsula due to structural complexity of the NAF at this location and the most recent earthquake to rupture the surface at Hersek Peninsula was the historical 1509 CE event. A restraining bend and bifurcation of the NAF at Hersek Peninsula suggests that this location might be a persistent asperity forming a surface rupture segmentation point at least since Pleistocene. Surface ruptures documented in palaeoseismic trenches north of the Hersek Lagoon and an offset 6th century East Roman aqueduct; however, suggests that this section of the NAF has ruptured the surface multiple times in the past and is highly likely to rupture again during the expected Marmara earthquake. The aqueduct; which crosses the surface trace of the NAF, is offset 14 ± 1 m and yields 13.6 ± 1 mm yr–1 dextral slip rate indicating that the northern branch of the NAF accrues and releases the majority of the stress between Eurasia and Anatolian block in the Marmara region. If the ∼125-km-long seismic gap between the 1912 and 1999 ruptures fail during a single event the expected Marmara earthquake can reach M7.4.
Extraction of GRACE/GRACE-FO observed mass change patterns across Antarctica via independent component analysis (ICA)
Authors: Shi Tianyan , Fukuda Yoichi , Doi Koichiro , Okuno Jun’ichi
Published: January 2022

Here we qualitatively analyse the mass change patterns across Antarctica via independent component analysis (ICA), a statistics-based blind source separation method to extract signals from complex data sets, in an attempt to reduce uncertainties in the glacial isostatic adjustment (GIA) effects and improve understanding of Antarctic Ice Sheet (AIS) mass-balance. We extract the six leading independent components from gravimetric data acquired during the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO) missions. The results reveal that the observed continental-scale mass changes can be effectively separated into several spatial patterns that may be dominated by different physical processes. Although the hidden independent physical processes cannot be completely isolated, some significant signals, such as glacier melt, snow accumulation, periodic climatic signals, and GIA effects, can be determined without introducing any external information. We also observe that the time period of the analysed data set has a direct impact on the ICA results, as the impacts of extreme events, such as the anomalously large snowfall events in the late 2000s, may cause dramatic spatial and temporal changes in the ICA results. ICA provides a unique and informative approach to obtain a better understanding of both AIS-scale mass changes and specific regional-scale spatiotemporal signal variations.
Eikonal surface wave tomography with smoothing splines—application to Southern California
Authors: Chevrot Sébastien , Lehujeur Maximilien
Published: January 2022

The densification of both permanent and temporary seismic networks has raised new interest in surface wave eikonal tomography from which phase velocity maps can be obtained without resolving a tomographic inverse problem. However, eikonal tomography requires to reconstruct traveltime surfaces from a discrete number of measurements obtained at the station locations, which can be challenging. We present a new method to reconstruct these traveltime surfaces with smoothing splines discretized in a regular 2-D Cartesian grid. We impose Neumann boundary conditions so that the phase gradients on the edges of the grid are equal to the apparent slownesses of the average plane wave along the normal direction measured by beamforming. Using the eikonal equation, phase velocity maps are then derived from the norm of the gradient of the interpolated traveltime maps. The method is applied to Rayleigh waves recorded by the Southern California Seismic Network to derive phase velocity surfaces. Robust, stable and finely resolved phase velocity maps at 25 and 33 s period are obtained after averaging the phase velocity maps derived from the analysis of a selection of recent large (Mw ≥ 6.5) teleseismic events. The phase velocity map at 25 s mainly constrains the thickness of the Southern California crust, with results that are in excellent agreement with previous tomographic studies.
Optimization of seismic-guided 3-D marine magnetotelluric imaging in a complex fold-thrust belt setting in NW Borneo, Malaysia
Authors: Saleh Ahmad Shahir bin , Meju Max A , Ismail Nur Azwin binti , Nawawi bin Mohd Nordin Mohd
Published: January 2022

The use of seismic-derived structure tensor to guide the inversion of non-seismic data has been gaining increasing attention because of its ability to constrain the inversion result to honour structural information from seismic reflectivity. While the cross-gradient method has been recently adapted to this problem, there is a need to further examine how the choice of the various regularization weighting factors and the design of the starting model impact the image-guided results. In this paper focused on marine magnetotellurics (MT), we study several practical aspects of seismic-guided electromagnetic (EM) inversion to see on what can be improved from the current practice. We then show practical examples of how the cross-gradient method can be applied to get a more geologically pleasing model that fits the data. We also show that there are subjective choices in how to effectively apply the method. First, using a field-realistic synthetic model, we established what would be the suitable regularization weights in the vertical and horizontal directions. Secondly, for the actual 3-D survey data, we compared the use of structure tensors derived from anisotropic pre-stack depth migration (APSDM) reflectivity, high-fidelity full-waveform inversion (FWI) velocity and acoustic impedance inversion volumes to guide cross-gradient anisotropic resistivity inversion with initial half-space resistivity starting models. We determined post-facto the optimum structure tensor weights using well logs as the ground truth. We found that the initial model built using horizon-based interpolated resistivity logs from multiple wells in the anisotropic inversion guided with seismic FWI velocity gave the best match to well logs as compared to the other options. However, given that resistivity logs from multiple wells may not always be available for a robust initial model construction in frontier exploration, we suggest that the structure tensor from APSDM reflectivity data is still preferred since the APSDM reflectivity data have well-defined structural information.
Efficacy of a Carrageenan Gel in Increasing Clearance of Anal Human Papillomavirus Infections in Men: Interim Analysis of a Double-Blind, Randomized Controlled Trial
Authors: Laurie Cassandra , El-Zein Mariam , Tota Joseph , Khosrow-Khavar Farzin , Tellier Pierre-Paul , Coutlée François , de Pokomandy Alexandra , Franco Eduardo L ,   Lubricant Investigation in Men to Inhibit Transmission of Human Papillomavirus Infection (LIMIT-HPV) Study Group, Rodrigues Allita , Morykon Natalia , Rodrigues Raphaela , Bouten Sheila , Shapiro Samantha , Tsyruk Olga , Leblanc Roger , Trottier Benoit , de Castro Christina , Proulx-Boucher Karène , Theriault Guillaume , Guénoun Julie , Comète Émilie
Published: January 2022

Preclinical studies have demonstrated carrageenan’s anti–human papillomavirus (HPV) activity. We assessed efficacy of a carrageenan-based gel compared to a placebo gel in increasing the clearance of anal HPV infections among gay, bisexual, and other men who have sex with men (gbMSM). Of 255 enrolled gbMSM, 134 were HPV positive at baseline and had valid HPV results for ≥2 visits. Carrageenan did not differ from placebo in clearing all baseline infections (hazard ratio, 0.84 [95% confidence interval, .31–2.27]), based on having 2 consecutive HPV-negative visits following at least 1 HPV-positive visit. There were no remarkable differences for analyses at the HPV type level or by human immunodeficiency virus status.

Clinical Trials Registration

NCT02354144.
Influence of daptomycin dose and fosfomycin susceptibility on outcome of vancomycin-resistant Enterococcus faecium bloodstream infections treated with daptomycin and fosfomycin combination
Authors: Chuang Yu-Chung , Tseng Tai-Chung , Wang Jann-Tay , Lin Chi-Ying , Huang Sung-Hsi , Chen Yee-Chun , Chang Shan-Chwen
Published: January 2022

Objectives

Synergistic combinations of daptomycin and β-lactam antibiotics are currently recommended for treatment of VRE bloodstream infection (BSI). The efficacy of these combinations is jeopardized by VRE inherently resistant to β-lactam antibiotics. The combination of daptomycin and fosfomycin is recommended as an alternative therapy for VRE BSI; however, clinical data to support use of this combination are lacking.

Patients and methods

We conducted a prospective observational multicentre study of patients treated with a combination of daptomycin and fosfomycin for VRE BSI during 2016–20. The primary outcome was 28 day mortality. Multivariable logistic regression was performed for outcome analysis.

Results

The study included 106 patients from 1112 VRE BSI episodes. The overall 28 day mortality was 40.6%. The median (IQR) daptomycin dose was 10.18 mg/kg (9.43–10.70). The fosfomycin dose was 16 g/day (8–22.5). Ninety-six isolates were available for MIC testing. The fosfomycin MIC was 32 mg/L in 6 (6.3%), 64 mg/L in 68 (70.8%) and ≥128 mg/L in 22 (22.9%) isolates. Independent of Charlson comorbidity index and Pitt bacteraemia score, fosfomycin MIC ≥128 mg/L [adjusted OR (aOR) = 3.05; 95% CI = 1.01–9.19; P = 0.047] and daptomycin dose (aOR = 0.64; 95% CI = 0.43–0.97; P = 0.04) predicted mortality.

Conclusions

Higher daptomycin dose and susceptibility to fosfomycin were independently associated with lower mortality in patients with VRE BSI. Our results suggest that higher doses of daptomycin are indicated for VRE BSI, whether or not it is used in combination with fosfomycin. The combination was less effective for patients with fosfomycin-resistant isolates.
Defining Transition Success for Young Adults with Inflammatory Bowel Disease According to Patients, Parents and Health Care Providers
Authors: Bihari Allison , Hamidi Nima , Seow Cynthia H , Goodman Karen J , Wine Eytan , Kroeker Karen I
Published: January 2022

Background

The transition from pediatric to adult care is associated with changes centered around the patient taking responsibility for their health. As the incidence of childhood-onset inflammatory bowel disease (IBD) is increasing, it is important to address gaps in transition literature—specifically, the indicators signifying achievement of transition success. The study objective was to define transition success according to patients, parents, and health care providers involved in IBD transition.

Methods

This study used the method of qualitative description to conduct semi-structured interviews with patients, parents, and health care providers. During interviews, demographic information was collected, and interviews were recorded and transcribed. Data analysis was conducted independently of each group using latent content analysis. Participant recruitment continued until thematic saturation was reached within each group.

Results

Patients, parents, and health care providers all defined transition success with the theme of independence in one’s care. The theme of disease management emerged within parent and provider groups, whereas the theme of relationship with/ trust in adult care team was common to patients and parents. Additional themes of care team management, general knowledge, care stability, and health outcomes emerged within specific groups.

Conclusion

This study demonstrated differences between how patients, parents, and health care providers view transition success. This finding reveals the value of using a multifaceted definition of transition success with input from all stakeholders. Further research should prioritize the identification of factors common to patients who do not reach transition success as defined by patients, their parents, and providers.
Digging ability and digging performance in a hyporheic gravel-dwelling crayfish, the hairy crayfish Cambarus friaufi (Hobbs 1953) (Decapoda: Astacidae: Cambaridae)
Authors: Graham Zackary A , Stubbs Megan B , Loughman Zachary J
Published: January 2022

Crayfishes are known for their ability to construct burrows, although there is intra- and interspecific variation in the complexity and reliance on such burrows. Crayfishes historically have been classified into ecological groupings based on their reliance on their burrow and the burrows connection to the water table. These ecological classifications, however, do not completely account for the behavioral diversity throughout crayfishes. One group of crayfishes that do not necessarily fit into these ecological classifications are members of the invalid subgenus Glareocola of Cambarus Erichson, 1846, which includes four species: C. brachydactylus (Hobbs, 1953), C. friaufi (Hobbs, 1953), C. polypilosus (Loughman & Williams, 2018), and C. williami (Bouchard & Bouchard 1995). All four species inhabit streams characterized by loose chert gravel, which creates ample interstitial spaces and potential access to the streambed’s hyporheic zone. We studied how one member of the Glareocola group, C. friaufi, exhibits unique morphological and behavioral adaptations that enable individuals to dig into the hyporheic zone of their natural chert substrate. We found that C. friaufi was sexually monomorphic regarding the relationship between body size and claw size, which contrasts findings from other stream-dwelling crayfish species. By evaluating the digging ability and digging performance of C. friaufi and sand, pea gravel, and their natural chert substrate, we also demonstrate how their digging ability is highly adapted to their natural chert substrate. Individuals of C. friaufi were either unable to dig or rarely dig underneath substrates other than chert. We discuss our results considering the behavioral ecology and natural history of the crayfishes within this enigmatic group.
A hybrid genetic–firefly algorithm for engineering design problems
Authors: El-Shorbagy M A , El-Refaey Adel M
Published: January 2022

Firefly algorithm (FA) is a new random swarm search optimization algorithm that is modeled after movement and the mutual attraction of flashing fireflies. The number of fitness comparisons and attractions in the FA varies depending on the attraction model. A large number of attractions can induce search oscillations, while a small number of attractions can cause early convergence and a large number of fitness comparisons that can add to the computational time complexity. This study aims to offer H-GA–FA, a hybrid algorithm that combines two metaheuristic algorithms, the genetic algorithm (GA) and the FA, to overcome the flaws of the FA and combine the benefits of both algorithms to solve engineering design problems (EDPs). In this hybrid system, which blends the concepts of GA and FA, individuals are formed in the new generation not only by GA processes but also by FA mechanisms to prevent falling into local optima, introduce sufficient diversity of the solutions, and make equilibrium between exploration/exploitation trends. On the other hand, to deal with the violation of constraints, a chaotic process was utilized to keep the solutions feasible. The proposed hybrid algorithm H-GA–FA is tested by well-known test problems that contain a set of 17 unconstrained multimodal test functions and 7 constrained benchmark problems, where the results have confirmed the superiority of H-GA–FA overoptimization search methods. Finally, the performance of the H-GA–FA is also investigated on many EDPs. Computational results show that the H-GA–FA algorithm is competitive and better than other optimization algorithms that solve EDPs.
A new approach for writer verification based on segments of handwritten graphemes
Authors: Aubin Verónica , Mora Marco , Santos Matilde
Published: January 2022

Traditional literature considers complex biometric sources such as words, letters and signatures for writer verification/identification. In this work the use of small segments of the handwritten stroke for writer verification is proposed. A grapheme is defined as the concatenation of smaller segments or fragments. Two models of grapheme are developed based on the idea that the segments are parts of a circle with or without direction. The average of Gray Level of the Perpendicular Line to the Skeleton and Local Binary Pattern are adopted as descriptors. A database of 3,000 images of 50 writers, with 6 types of segments and with 10 samples per segment has been developed. A binary output support vector machine was applied as classifier. Thus, 50 classifiers were trained using 100 balanced data sets generated using subsampling of the majority class. Experiments are carried out with the proposed models, with an identity verification hit rate of 97 % on average. The positive results of experiments show that it is possible to achieve high precision in writer verification using segment of graphemes.
Olaparib in patients with mCRPC with homologous recombination repair gene alterations: PROfound Asian subset analysis
Authors: Matsubara Nobuaki , Nishimura Kazuo , Kawakami Satoru , Joung Jae Young , Uemura Hiroji , Goto Takayuki , Kwon Tae Gyun , Sugimoto Mikio , Kato Masashi , Wang Shian-Shiang , Pang See-Tong , Chen Chung-Hsin , Fujita Tomoko , Nii Masahiro , Shen Liji , Dujka Melanie , Hussain Maha , de Bono Johann
Published: January 2022

Background

The Phase III PROfound study (NCT02987543) evaluated olaparib versus abiraterone or enzalutamide (control; randomized 2:1 to olaparib or control) in men with homologous recombination repair gene alterations and metastatic castration-resistant prostate cancer whose disease progressed on prior next-generation hormonal agent.

Methods

We present efficacy and safety data from an exploratory post hoc analysis of olaparib in the PROfound Asian subset. Analyses were not planned, alpha controlled or powered. Of 101 Asian patients enrolled in Japan (n=57), South Korea (n=29) and Taiwan (n=15), 66 and 35 patients received olaparib and control, respectively.

Results

Radiographic progression-free survival (rPFS) and overall survival (OS) favored olaparib versus control in Cohort A [rPFS 7.2 vs. 4.5 months, HR 0.58, 95% CI 0.29–1.21, P = 0.14 (nominal); OS 23.4 vs. 17.8 months, HR 0.81, 95% CI 0.40–1.74, P = 0.57 (nominal)] and Cohorts A+B [rPFS 5.8 vs. 3.5 months, HR 0.69, 95% CI 0.42–1.16, P = 0.13 (nominal); OS 18.6 vs. 16.2 months, HR 0.96, 95% CI 0.56–1.70, P = 0.9 (nominal)]. Olaparib showed greatest improvement in patients harboring BRCA alterations [rPFS 9.3 vs. 3.5 months, HR 0.17, 95% CI 0.06–0.49, P = 0.0003 (nominal); OS 26.8 vs. 14.3 months, HR 0.62, 95% CI 0.24–1.79, P = 0.34 (nominal)]. Safety data were consistent with the known profile of olaparib, with no new safety signals identified.

Conclusion

In PROfound, there was a statistically significant improvement in outcomes reported in the global population of patients with metastatic castration-resistant prostate cancer and alterations in homologous recombination repair genes whose disease progressed on prior next-generation hormonal agent compared with control. For the subset of Asian patients reported here, exploratory analysis suggested that there was also an improvement in outcomes versus control. The safety and tolerability of olaparib in Asian patients were similar to that of the PROfound global population.

Clinical trial number

ClinicalTrials.gov NCT02987543
Small mammal dynamics in snow-covered forests
Authors: Scott Allison M , Gilbert Jonathan H , Pauli Jonathan N
Published: January 2022

In seasonal environments, the winter months can drive the structure and dynamics of vertebrate communities. Most ecological studies have focused on species above the snow, overlooking those within the subnivium (below-snow environment). The Great Lakes region of North America is characterized by seasonal snow cover and a diverse assemblage of small mammals, both of which are changing rapidly in response to a changing climate. To study the seasonal dynamics of small mammals, we sampled communities in three forest types (hardwood, hemlock-cedar, and spruce bog) in summer and winter over 2 years. We hypothesized that seasonal differences in communities would be moderated by forest structure in summer and snow in winter. We assessed community dominance via species diversity and the abundances of deer mice (Peromyscus maniculatus), white-footed mice (P. leucopus), and southern red-backed voles (Myodes gapperi). We estimated a Community Temperature Index (CTI; a metric of the balance between warm- and cold-adapted species in a community) and tested seasonal drivers of CTI. Species diversity was highest in spruce bogs in winter due to increased species evenness, but diversity was consistent year-round in hardwood and hemlock-cedar forests due to unchanging species dominance. Spruce bogs supported the coldest CTI in summer, but CTIs converged across forest types in winter. In summer, forest structure drove CTI; in winter, colder CTIs were associated with deeper snow and a warmer subnivium. Our work reveals that snow is a critical habitat and filter for cold-adapted species that ultimately structures small mammal communities. Given rapid changes in snow conditions due to climate change, we predict continued range contractions for subnivium-adapted species.
Forage selection by Masai giraffes (Giraffa camelopardalis tippelskirchi) at multiple spatial scales
Authors: Levi Matana , Lee Derek E , Bond Monica L , Treydte Anna C
Published: January 2022

Management of rangelands requires knowledge of forage species that are preferred or avoided by wildlife and livestock. A recent expansion of woody vegetation into previously open grasslands in African savanna ecosystems negatively impacts many mammalian grazers. Nevertheless, the ecological role of bush encroacher plant species as food may present a benefit for browsing species. We quantified diet selection by Masai giraffes (Giraffa camelopardalis tippelskirchi) through foraging observations and vegetation sampling in the Tarangire Ecosystem of Tanzania, which includes large areas of a native shrub that livestock managers have classified as an encroacher species (Dichrostachys cinerea). We compared woody plant species used by giraffes for foraging with availability at two different spatial scales during the wet and dry seasons. Giraffes selected some woody plants such as Vachellia species while significantly avoiding others, both at the local and landscape scales. Giraffes preferred foraging on D. cinerea at both spatial scales and in both the wet and dry seasons. Management that has focused on benefiting grazing livestock by removal of encroaching species (e.g., D. cinerea) may have unintended consequences for wildlife, especially for browsing species like giraffes that feed extensively on the expanding bush species.
The swollen lip: unusual presentation of furuncular myiasis in a returning traveller
Authors: Schubert Lorenz , Tobudic Selma , Sillaber Christian , Winkler Stefan
Published: January 2022

Furuncular myiasis, caused by Cordylobia anthropophaga, is rarely seen in homecoming travellers from Africa. Here, we describe an uncommon case of furuncular myiasis of the lip in a homecoming traveller from Cameroon and demonstrate clinical management by a series of images.
Persistent abdominal symptoms in returning travellers: clinical and molecular findings
Authors: Gefen-Halevi Shiraz , Biber Asaf , Gazit Zeala , Amit Sharon , Belausov Natasha , Keller Nati , Smollan Gill , Schwartz Eli
Published: January 2022

Background

Persistent abdominal symptoms (PAS) are the leading cause of post-travel morbidity although there is a paucity of evidence concerning the aetiology of this condition. Recently molecular methods for protozoa detection in stool have been introduced. Herein, we describe the clinical aspects and the prevalence of gastrointestinal protozoa in returning travellers with PAS.

Methods

From 2017 to 2019, clinical information and stool specimens from returning travellers with PAS were analysed for the presence of parasites using the Allplex-GI-Parasite-assay. Stool findings from symptomatic patients without a travel history were used as a comparator.

Results

During the 2-year study, 203 stool specimens from returning travellers were analysed. The median duration of symptoms before seeking care was 6 months, the most common symptoms were fatigue (79.2%), abdominal pain (75.7%) and loose stool (70.8%).

Most of travellers had returned from Asia (57.6%), mainly from the Indian-subcontinent and only 52.6% were backpackers. Altogether, 36.9% samples were positive for protozoa, with Blastocystis hominis being the most common (26.6%) in samples, followed by Dientamoeba fragilis (18.7%), Giardia lamblia (3.0%) and Cryptosporidium spp (0.5%). The former two were dominant in all regions. In all cases but one, G. lamblia was acquired, but one were acquired in the Indian subcontinent (odds ratios 16.9; 95% confidence intervals: 1.9–148.3). Entamoeba histolytica was not detected. The demographic characterization of the 1359 non-travellers was comparable with the travellers. Among them D. fragilis was the most common followed by B. hominis, which was significantly less frequent compared among the travellers (16.7% vs 26.6%, P < 0.001). Average Cycle threshold values for each stool parasites were comparable between the two groups.

Conclusion

Among returning travellers with PAS, more than one-third were positive for gastrointestinal protozoa. A low rate of giardia was found and no E. histolytica while B. hominis followed by D. fragilis were the dominant findings. Further studies are required to better understand the role of these protozoa in PAS.
Drought stress increases the expression of barley defence genes with negative consequences for infesting cereal aphids
Authors: Leybourne Daniel J , Valentine Tracy A , Binnie Kirsty , Taylor Anna , Karley Alison J , Bos Jorunn I B
Published: January 2022

Crops are exposed to myriad abiotic and biotic stressors with negative consequences. Two stressors that are expected to increase under climate change are drought and infestation with herbivorous insects, including important aphid species. Expanding our understanding of the impact drought has on the plant–aphid relationship will become increasingly important under future climate scenarios. Here we use a previously characterized plant–aphid system comprising a susceptible variety of barley, a wild relative of barley with partial aphid resistance, and the bird cherry-oat aphid to examine the drought–plant–aphid relationship. We show that drought has a negative effect on plant physiology and aphid fitness, and provide evidence to suggest that plant resistance influences aphid responses to drought stress. Furthermore, we show that the expression of thionin genes, plant defensive compounds that contribute to aphid resistance, increase in susceptible plants exposed to drought stress but remain at constant levels in the partially resistant plant, suggesting that they play an important role in determining the success of aphid populations. This study highlights the role of plant defensive processes in mediating the interactions between the environment, plants, and herbivorous insects.
Regulation of lignin biosynthesis by an atypical bHLH protein CmHLB inChrysanthemum
Authors: Zhao Wenqian , Ding Lian , Liu Jiayou , Zhang Xue , Li Song , Zhao Kunkun , Guan Yunxiao , Song Aiping , Wang Haibin , Chen Sumei , Jiang Jiafu , Chen Fadi
Published: January 2022

Stem mechanical strength is one of the most important agronomic traits that affects the resistance of plants against insects and lodging, and plays an essential role in the quality and yield of plants. Several transcription factors regulate mechanical strength in crops. However, mechanisms of stem strength formation and regulation remain largely unexplored, especially in ornamental plants. In this study, we identified an atypical bHLH transcription factor CmHLB (HLH PROTEIN INVOLVED IN LIGNIN BIOSYNTHESIS) in chrysanthemum, belonging to a small bHLH sub-family — the PACLOBUTRAZOL RESISTANCE (PRE) family. Overexpression of CmHLB in chrysanthemum significantly increased mechanical strength of the stem, cell wall thickness, and lignin content, compared with the wild type. In contrast, CmHLB RNA interference lines exhibited the opposite phenotypes. RNA-seq analysis indicated that CmHLB promoted the expression of genes involved in lignin biosynthesis. Furthermore, we demonstrated that CmHLB interacted with Chrysanthemum KNOTTED ARABIDOPSIS THALIANA7 (CmKNAT7) through the KNOX2 domain, which has a conserved function, i.e. it negatively regulates secondary cell wall formation of fibres and lignin biosynthesis. Collectively, our results reveal a novel role for CmHLB in regulating lignin biosynthesis by interacting with CmKNAT7 and affecting stem mechanical strength in Chrysanthemum.
Does oxygen affect ageing mechanisms of Pinus densiflora seeds? A matter of cytoplasmic physical state
Authors: Gerna Davide , Ballesteros Daniel , Arc Erwann , Stöggl Wolfgang , Seal Charlotte E , Marami-Zonouz Nicki , Na Chae Sun , Kranner Ilse , Roach Thomas
Published: January 2022

During desiccation, the cytoplasm of orthodox seeds solidifies into an intracellular glass with highly restricted diffusion and molecular mobility. Temperature and water content govern seed ageing rates, while oxygen (O2) can promote deteriorative reactions. However, whether the cytoplasmic physical state affects involvement of O2 in seed ageing remains unresolved. We aged Pinus densiflora seeds by controlled deterioration (CD) at 45 °C and distinct relative humidity (RH), resulting in cells with a glassy (11% and 30% RH) or fluid (60% and 80% RH) cytoplasm. Hypoxic conditions (0.4% O2) during CD delayed seed deterioration, lipid peroxidation, and decline of antioxidants (glutathione, α-tocopherol, and γ-tocopherol), but only when the cytoplasm was glassy. In contrast, when the cytoplasm was fluid, seeds deteriorated at the same rate regardless of O2 availability, while being associated with limited lipid peroxidation, detoxification of lipid peroxide products, substantial loss of glutathione, and resumption of glutathione synthesis. Changes in metabolite profiles provided evidence of other O2-independent enzymatic reactions in a fluid cytoplasm, including aldo-keto reductase and glutamate decarboxylase activities. Biochemical profiles of seeds stored under seed bank conditions resembled those obtained after CD regimes that maintained a glassy cytoplasm. Overall, O2 contributed more to seed ageing when the cytoplasm was glassy, rather than fluid.
Observations of the initial formation and evolution of spiral galaxies at 1 < z < 3 in the CANDELS fields
Authors: Margalef-Bentabol Berta , Conselice Christopher J , Haeussler Boris , Casteels Kevin , Lintott Chris , Masters Karen , Simmons Brooke
Published: January 2022

Many aspects concerning the formation of spiral and disc galaxies remain unresolved, despite their discovery and detailed study over the past 150 yr. As such, we present the results of an observational search for proto-spiral galaxies and their earliest formation, including the discovery of a significant population of spiral-like and clumpy galaxies at z > 1 in deep Hubble Space Telescope CANDELS imaging. We carry out a detailed analysis of this population, characterizing their number density evolution, masses, star formation rates (SFR), and sizes. Overall, we find a surprisingly high overall number density of massive $M_{*} \gt 10^{10}\, \mathrm{M}_{\odot }$ spiral-like galaxies (including clumpy spirals) at z > 1 of $0.18\, {\rm per}\, \mathrm{arcmin}^{-2}$. We measure and characterize the decline in the number of these systems at higher redshift using simulations to correct for redshift effects in identifications, finding that the true fraction of spiral-like galaxies grows at lower redshifts as ∼ (1 + z)−1.1. This is such that the absolute numbers of spirals increases by a factor of ∼10 between z = 2.5 and z = 0.5. We also demonstrate that these spiral-like systems have large sizes at z > 2, and high SFRs, above the main-sequence, These galaxies represent a major mode of galaxy formation in the early Universe, perhaps driven by the spiral structure itself. We finally discuss the origin of these systems, including their likely formation through gas accretion and minor mergers, but conclude that major mergers are an unlikely cause.
Dark Energy Survey Year 3 results: galaxy clustering and systematics treatment for lens galaxy samples
Authors: Rodríguez-Monroy M , Weaverdyck N , Elvin-Poole J , Crocce M , Carnero Rosell A , Andrade-Oliveira F , Avila S , Bechtol K , Bernstein G M , Blazek J , Camacho H , Cawthon R , De Vicente J , DeRose J , Dodelson S , Everett S , Fang X , Ferrero I , Ferté A , Friedrich O , Gaztanaga E , Giannini G , Gruendl R A , Hartley W G , Herner K , Huff E M , Jarvis M , Krause E , MacCrann N , Mena-Fernández J , Muir J , Pandey S , Park Y , Porredon A , Prat J , Rosenfeld R , Ross A J , Rozo E , Rykoff E S , Sanchez E , Sanchez Cid D , Sevilla-Noarbe I , Tabbutt M , To C , Wagoner E L , Wechsler R H , Aguena M , Allam S , Amon A , Annis J , Bacon D , Baxter E , Bertin E , Bhargava S , Brooks D , Burke D L , Carrasco Kind M , Carretero J , Castander F J , Choi A , Conselice C , Costanzi M , da Costa L N , Pereira M E S , Desai S , Diehl H T , Flaugher B , Fosalba P , Frieman J , García-Bellido J , Giannantonio T , Gruen D , Gschwend J , Gutierrez G , Hinton S R , Hollowood D L , Honscheid K , Huterer D , Jain B , James D J , Kuehn K , Kuropatkin N , Lima M , Maia M A G , March M , Marshall J L , Melchior P , Menanteau F , Miller C J , Miquel R , Mohr J J , Morgan R , Palmese A , Paz-Chinchón F , Pieres A , Plazas Malagón A A , Roodman A , Scarpine V , Serrano S , Smith M , Soares-Santos M , Suchyta E , Tarle G , Thomas D , Varga T N ,   (DES Collaboration)
Published: January 2022

In this work, we present the galaxy clustering measurements of the two DES lens galaxy samples: a magnitude-limited sample optimized for the measurement of cosmological parameters, maglim, and a sample of luminous red galaxies selected with the redmagic algorithm. maglim/redmagic sample contains over 10 million/2.5 million galaxies and is divided into six/five photometric redshift bins spanning the range z ∈ [0.20, 1.05]/z ∈ [0.15, 0.90]. Both samples cover 4143 $\deg ^2$ over which we perform our analysis blind, measuring the angular correlation function with an S/N ∼ 63 for both samples. In a companion paper, these measurements of galaxy clustering are combined with the correlation functions of cosmic shear and galaxy–galaxy lensing of each sample to place cosmological constraints with a 3 × 2pt analysis. We conduct a thorough study of the mitigation of systematic effects caused by the spatially varying survey properties and we correct the measurements to remove artificial clustering signals. We employ several decontamination methods with different configurations to ensure the robustness of our corrections and to determine the systematic uncertainty that needs to be considered for the final cosmology analyses. We validate our fiducial methodology using lognormal mocks, showing that our decontamination procedure induces biases no greater than 0.5σ in the (Ωm, b) plane, where b is the galaxy bias.
The nozzle shock in tidal disruption events
Authors: Bonnerot Clément , Lu Wenbin
Published: January 2022

Tidal disruption events (TDEs) occur when a star gets torn apart by the strong tidal forces of a supermassive black hole, which results in the formation of a debris stream that partly falls back towards the compact object. This gas moves along inclined orbital planes that intersect near pericentre, resulting in a so-called ‘nozzle shock’. We perform the first dedicated study of this interaction, making use of a two-dimensional simulation that follows the transverse gas evolution inside a given section of stream. This numerical approach circumvents the lack of resolution encountered near pericentre passage in global three-dimensional simulations using particle-based methods. As it moves inward, we find that the gas motion is purely ballistic, which near pericentre causes strong vertical compression that squeezes the stream into a thin sheet. Dissipation takes place at the resulting nozzle shock, inducing a rise in pressure that causes the collapsing gas to bounce back, although without imparting significant net expansion. As it recedes to larger distances, this matter continues to expand while remaining thin despite the influence of pressure forces. This gas evolution specifies the strength of the subsequent self-crossing shock, which we find to be more affected by black hole spin than previously estimated. We also evaluate the impact of general relativistic effects, viscous dissipation, magnetic fields, and radiative processes on the nozzle shock. This study represents an important step forward in the theoretical understanding of TDEs, bridging the gap between our robust knowledge of the fallback rate and the more complex following stages, during which most of the emission occurs.
Scattering and sublimation: a multiscale view of µm-sized dust in the inclined disc of HD 145718
Authors: Davies Claire L , Rich Evan A , Harries Tim J , Monnier John D , Laws Anna S E , Andrews Sean M , Bae Jaehan , Wilner David J , Anugu Narsireddy , Ennis Jacob , Gardner Tyler , Kraus Stefan , Labdon Aaron , le Bouquin Jean-Baptiste , Lanthermann Cyprien , Schaefer Gail H , Setterholm Benjamin R , ten Brummelaar Theo ,   G-LIGHTS collaboration
Published: January 2022

We present multi-instrument observations of the disc around the Herbig Ae star, HD 145718, employing geometric and Monte Carlo radiative transfer models to explore the disc orientation, the vertical and radial extent of the near-infrared (NIR) scattering surface, and the properties of the dust in the disc surface and sublimation rim. The disc appears inclined at 67–71°, with position angle, PA = −1.0 to 0.6°, consistent with previous estimates. The NIR scattering surface extends out to ${\sim}75\,$ au and we infer an aspect ratio, hscat(r)/r ∼ 0.24 in J band; ∼0.22 in H band. Our Gemini Planet Imager images and VLTI + CHARA NIR interferometry suggest that the disc surface layers are populated by grains ≳λ/2π in size, indicating these grains are aerodynamically supported against settling and/or the density of smaller grains is relatively low. We demonstrate that our geometric analysis provides a reasonable assessment of the height of the NIR scattering surface at the outer edge of the disc and, if the inclination can be independently constrained, has the potential to probe the flaring exponent of the scattering surface in similarly inclined (i ≳ 70°) discs. In re-evaluating HD 145718’s stellar properties, we found that the object’s dimming events – previously characterized as UX Or and dipper variability – are consistent with dust occultation by grains larger, on average, than found in the ISM. This occulting dust likely originates close to the inferred dust sublimation radius at $0.17\,$ au.
AGN light echoes and the accretion disc self-gravity limit
Authors: Lobban Andrew , King Andrew
Published: January 2022

Accretion disc theory predicts that an AGN disc becomes self-gravitating and breaks up into stars at an outer radius Rsg ≃ 12 light-days, with effectively no free parameter. We present evidence that the longest observed AGN light echoes are all close to 12 d in the AGN rest frames. These observations give a stringent test of the AGN disc theory. Further monitoring should offer insight into the formation angular momentum of the gas forming the disc. For distant AGN, observed lags significantly longer than 12 d give lower limits on their redshifts.