bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of a bilayer NiCrAlY/YSZ coating on IN713 LC superalloy by laser cladding
Authors: Khorram Ali , Nicknia Maysam
Published: September 2023

In this study, bilayer laser cladding of Inconel 713LC superalloy was performed by a Nd:YAG laser. Amdry 997 powder was used as the first layer and Metco 204NS ceramic powder as the second layer. The experiments were carried out with different laser parameters to investigate the influence of heat input and laser power density on the microstructure and the hardness of coating. The study revealed that the susceptibility to crack formation in the clad zone increases with the increase in the heat input due to the high cooling rate and intense thermal stress. The formation of shrinkage cavities in the lower half of the clad zone raises with the increase in the heat input owing to reduction in the solidification rate. Microstructural investigations show that a cellular structure is formed at the interface region. The middle area of coating features columnar dendrites, while the upper area of the coating displays very small equiaxed dendrites. The coating mainly comprises γ-Ni, β-NiAl and γ′-Ni3Al phases and the elements of Ni, Co, Cr, Al, Ta, Zr, and Y are homogeneously distributed in the clad zone. As the heat input increases, the microhardness of the samples decreases due to an increase in the dilution ratio. This leads to a decrease of Co, Cr, and Ta elements in the γ′ and the β intermetallic compounds, as well as a reduction of Zr and Y elements in the clad zone.
Controllable optical bistability in a Fabry–Pérot cavity with a nonlinear three-dimensional Dirac semimetal
Authors: Yuan 袁 Hong-Xia 红霞 , Li 李 Jia-Xue 佳雪 , Ma 马 Qi-Jun 奇军 , Tian 田 Hai-Shan 海山 , Ye 叶 Yun-Yang 云洋 , Luo 罗 Wen-Xin 文昕 , Wu 吴 Xing-Hua 杏华 , Jiang 蒋 Le-Yong 乐勇
Published: September 2023

Optical bistability (OB) is capable of rapidly and reversibly transforming a parameter of an optical signal from one state to another, and homologous nonlinear optical bistable devices are core components of high-speed all-optical communication and all-optical networks. In this paper, we theoretically investigated the controllable OB from a Fabry–Pérot (FP) cavity with a nonlinear three-dimensional Dirac semimetal (3D DSM) in the terahertz band. The OB stems from the third-order nonlinear bulk conductivity of the 3D DSM and the resonance mode has a positive effect on the generation of OB. This FP cavity structure is able to tune the OB because the transmittance and the reflectance can be modulated by the Fermi energy of the 3D DSM. We believe that this FP cavity configuration could provide a reference concept for realizing tunable bistable devices.
Development of a hybrid line dosimeter using lead (II) iodide and Gd2O2S:Tb for dose monitoring in brachytherapy
Authors: Yang S.W. , Park S.K. , Moon C.W. , Min B.I. , Heo Y.J.
Published: September 2023

In brachytherapy, a radiation source is injected into the
human body, and accurate evaluation of the source location is
critical for patient safety. However, identification of the source
location each time is difficult. Therefore, in this study, a
PbI2-based hybrid line dosimeter that can reduce drift current
while measuring dose in real time was fabricated by adding
Gd2O2S:Tb (0–20 wt%), and the sensitivity of the hybrid
line sensor was characterized using an 192Ir source. Before
creating the line dosimeter, a unit-cell sensor was fabricated to
define the optimal addition of Gd2O2S:Tb. The results
showed that a dosimeter with 20 wt% Gd2O2S:Tb yielded
the lowest drift current, which was 92% lower than that with
PbI2alone (relative standard deviation [RSD], 0.73%) to allow
the most stable signal output. Evaluation of the line dosimeter
showed that the signal output was stable with
RSD ≤ 1.5% and R
2 ≥ 0.9990 for all 25 pixels
except one. The sensitivity was high at the pixel closest to the
source location, and the accuracy of the source location was as high
as ±2 mm. The PbI2-based hybrid line dosimeter with
Gd2O2S:Tb fabricated in this study was shown to be
applicable as a dosimeter to determine the source location
accurately in brachytherapy.
A low-power neutron and gamma-ray detector for environmental radiation monitoring using CLYC scintillator
Authors: Zhao K. , Huang Y. , Shan C. , Feng C. , Wang Z. , Chang K. , Xie W. , Liu F. , Liu S.
Published: September 2023

This paper describes a low-power neutron and gamma-ray
detector based on a CLYC scintillator enriched with 96% 6Li
for environmental radiation monitoring. The detector is designed in
compliance with the IP66 standard having water and dust release
capability. The power consumption of the detector is 3.5 W, and the
operating temperature is from -15° to +40°. The energy
response range for gamma rays is 40 keV to 3 MeV, while the energy
resolution of the detector is 4.8% (662 keV). A standard figure
of merit (FOM) is used to evaluate neutron-gamma discrimination,
achieving a value of 3.42. The mixed neutron-gamma environment was
simulated at the Back-n neutron beam of the China Spallation Neutron
Source (CSNS). The test results show that the detector can detect
the changes in the gamma dose and neutron count rates when the beam
is turned on and off in real-time. The proposed detector is suitable
for the application of long-term environmental radiation monitoring
for nuclear facilities or buildings housing radioactive sources.
Mitigation of ventilation air methane (VAM) using novel methanotrophic coating materials: a technical analysis
Authors: Lundberg Daniel James , Kim Jimin , Parviz Dorsa , Strano Michael S
Published: September 2023

Ventilation air methane (VAM) is a potent greenhouse gas source originating from geological wells, current and extinct mineshafts and other terrestrial conduits venting methane to the atmosphere, contributing to global methane emissions and disproportionate warming potential. Herein, we introduce the concept of the methanotrophic material as an engineering solution. Such materials should be capable of converting methane at ambient temperatures and pressures to a binder product, capturing and permanently sequestering the methane while simultaneously restricting its further emission. While such materials are currently under research development, this goal is supported and facilities by the mathematical framework, introduced and used herein, to evaluate the ability to convert methane, using currently published activity data. We include a case study of the conversion of a characteristic stream of VAM (0.6% methane in air, 1.7 × 108 l hr−1 equivalent to 100 000 standard cubic feet per minute). We show that when appropriately designed, such systems require a surface coverage of less than 1000 m of mine tunnel length (equivalent to 20 000 m2 areal coverage) in order to reduce the methane emission from this stream by over 99%. Finally, we highlight formaldehyde as a reactive intermediate of methane oxidation which may itself be incorporated into these coating materials. As a component of binders and polymers already used ubiquitously in commercial products, this intermediate ultimately allows these systems to sequester the carbon from methane in a stable and solid form. The results presented here are easily extended to the treatment of other methane streams—either more concentrated or dilute—and the results herein will guide the design and development of a new class of carbon-negative materials.
The patterns, magnitude, and drivers of unprecedented 2022 mega-drought in the Yangtze River Basin, China
Authors: Liu Yi , Yuan Shanshui , Zhu Ye , Ren Liliang , Chen Ruiqi , Zhu Xiaotong , Xia Ruize
Published: September 2023

The Yangtze River Basin in China was hit by an unprecedented extreme drought in 2022. Such a record-breaking event is jointly driven by a few outlier factors and shows abnormal phenomena. The exceptionality of this drought event cannot be fully described by any individual indicator. Therefore, we performed this comprehensive study to highlight the exceptionality of 2022 Yangtze River Basin drought. We evaluated three drought characteristics: onset period (the time interval of moisture condition from normal to extreme), intensity, and affected area and their compound features. Additionally, historical climatology (1950–2022) and four past severe events are used as references. Lastly, we investigated the driving mechanisms of this event from synoptic perspective. Our results indicate the 2022 drought ranked as the most severe event in history. The recurrence interval of the 2022 Yangtze River drought is estimated to be 120–400 years by considering individual and combined drought characteristics. Behind the scenes, the synoptic environment triggered the abnormally high temperatures and abrupt alteration of precipitation, which is the main driver of the event. The 2022 Yangtze River drought is an archetype of an event characterized by both rapid intensification over time and space, which is indicative for drought monitoring and early warning in a warming climate.
Lenacapavir: A first-in-class capsid inhibitor for the treatment of highly treatment-resistant HIV
Authors: Prather Caitlin , Lee Andrea , Yen Carolynne
Published: September 2023

Purpose

The purpose of this article is to review the pharmacology, efficacy, and safety of the capsid inhibitor lenacapavir for the treatment of multidrug-resistant human immunodeficiency virus type 1 (HIV-1) infection.

A review of the literature was performed by searching PubMed/MEDLINE for all relevant articles published between February 2021 and March 2023 using the keywords “lenacapavir,” “Sunlenca,” “human immunodeficiency virus,” and “treatment” together with “multidrug resistant human immunodeficiency virus.” All English-language articles describing clinical trials assessing the efficacy and safety of lenacapavir when used in humans for the treatment of HIV infection were included. Review articles, conference abstracts, and article references were evaluated for relevant information, and data were also obtained from the manufacturer’s website and the package insert. Lenacapavir has been approved by the Food and Drug Administration (FDA) for the treatment of HIV-1 infection in heavily treatment-experienced adults with multidrug resistance for whom the current antiretroviral regimen is failing due to resistance, intolerance, or safety considerations. It is the first in a new class of drugs called capsid inhibitors to receive FDA approval. Lenacapavir is a long-acting subcutaneous injectable to be administered once every 6 months. The phase 3 clinical trial evaluating lenacapavir has demonstrated its efficacy in viral load reduction from baseline compared to placebo in patients receiving optimized background therapy. The most common adverse events reported in the clinical trial were injection site reactions, occurring in 63% of participants.

Conclusion

Lenacapavir is a novel capsid inhibitor indicated, in combination with other antiretroviral therapy, for treatment of multidrug-resistant HIV-1 infection.
Associating night-shift work with lifetime use of sleep medication and sleep quality in a cohort of female nurses
Authors: van de Langenberg Daniëlla , Vlaanderen Jelle , Berentzen Nina , Kromhout Hans , Vermeulen Roel
Published: September 2023

Night-shift workers often sleep at moments, not in sync with their circadian rhythm. Though the acute effects of night-shift work on sleep quality directly after a night shift are well described, less is known about the chronic effects of night-shift work on sleep. We associated ever-working night shifts and recently working night shifts (<4 wk) with lifetime use of sleep medication and melatonin, self-reported average sleep duration and sleep quality over the 4 wk preceding inclusion (measured using the Medical Outcomes Study Sleep scale). We explored trends in sleep outcomes with average frequency of night shifts per week, tenure of night-shift works in years, and time since last performed night work. This research was conducted within the Nightingale study which is a Dutch cohort study of 59,947 female registered nurses aged 18 to 65. Working night shifts was not associated with self-reported nonoptimal sleep length and sleep quality. However, we observed higher odds of lifetime use of sleep medication for nurses who ever-worked night shifts (OR 1.24; 95% CI 1.13, 1.35) and who recently worked night shifts (OR 1.13; 95% CI 1.05, 1.22); with night-shift work frequency and tenure being associated with lifetime use of sleep medication (P-value for trend < 0.001 for both). Odds for melatonin use were elevated for nurses who ever worked night shifts (OR 1.55; 95% CI 1.40, 1.71) and recently worked night shifts (OR 1.72; 95% CI 1.59, 1,86). The findings of this study have practical implications for healthcare organizations that employ nurses working night shifts. The observed associations between night-shift work and increased lifetime use of prescribed sleep medication and melatonin highlight the need for targeted support and interventions to address the potential long-term sleep problems faced by these nurses.
The Mastoid Crevasse and 3-Dimensional Considerations in Deep Plane Neck Lifting
Authors: Talei Benjamin , Shauly Orr , Marxen Troy , Menon Ambika , Gould Daniel J
Published: September 2023

Background

Advances in face and neck lifting involve release of tethering points along the superficial musculoaponeurotic system–platysma complex to freely manipulate the deep natural glide plane in the face and neck.

Objectives

The aim of this article was to determine a combination of deep plane techniques for addressing the face and neck and to elucidate, for the first time, a measurable endpoint for the gonial angle. Analysis of deep plane tethering and decussation zones was also undertaken.

Methods

Extended deep plane surgery performed in 79 patients (158 hemifaces; age, 30-75 years; 95% female), over a 3-month period, was reviewed. Patients were followed for 1 year. Measurements were performed systematically during deep plane face and neck lifting.

Results

Before intervention, the mean [standard deviation] gonial depth was 9.4 [3.6] mm on the left and 8.3 [2.7] mm on the right. The mean depth created below the gonial angle when measuring the traditional suspension to the anterior mastoid was 15.8 [3.3] mm on the left and 13.7 [2.5] mm on the right. The distance postoperatively when measuring the gonial depth after performing the crevasse technique was 23.2 [2.2] mm on the left and 22.5 [2.5] mm on the right. This represents a mean increase in the advancement of 7.4 mm on the left and 8.8 mm on the right (average, 8.1 mm) which was demonstrated to be statistically significant bilaterally (P < .0001).

Conclusions

The deep plane techniques described here aid manipulation of the deep plane and deep neck space, while also providing measurable endpoints and more effective modes of fixation by utilizing the mastoid crevasse. The use of techniques that release tension and allow redrape produce the most natural and well-balanced results.

Level of Evidence: 4
Taxonomic disagreement about ranks in gray-area taxa: A vignette study
Authors: Conix Stijn , Cuypers Vincent , Zachos Frank E , De Block Andreas
Published: September 2023

When producing species classifications, taxonomists are often confronted with gray-area cases. For example, because of incipient or shallow divergence, it can be scientifically valid both to split groups of organisms into separate species and to lump them together into one species. It has been claimed that, in such cases, the ranking decision is, in part, subjective and may differ between taxonomists because of differences in their conceptions of species or even in conservation values. In the present article, we use a vignette study to empirically test this claim and to explore the drivers of taxonomic decision-making in gray-area cases. For three fictional taxonomic scenarios, we asked the opinion of a sample of taxonomists on one of slightly different versions of an abstract containing a decision on species status. The cases were explicitly designed to represent gray-area cases, and the differences between versions related to potential drivers of decisions, such as information on conservation status, different kinds of additional evidence, and information on the presence or absence of gene flow. In general, our results suggest that taxonomists tend to disagree at least moderately about species-ranking decisions in gray-area cases even when they are presented with the same data. We did not find evidence that species concepts or conservation values are strong drivers of taxonomic disagreement. Instead, operational concerns, such as the presence or absence of different kinds of data, seemed to be more important.
Afrofemtrism: a critical examination of the relationship between gender, technology, and society
Authors: Ackah Betty B B
Published: September 2023

Existing theories in technology and society studies do not comprehensively address the realities of people of African descent, including factors such as their histories, evolving cultures, and power dynamics. The article addresses this gap by constructing afrofemtrism, a gender justice theory which interrogates gender realities in the context of a society’s peculiar interaction with technological advancements. A salient feature of afrofemtrism’s development is the iterative interaction with empirical data from the Ghana blockchain community wherein participants in this study encountered conflicts and congruity between their information and communications technology (ICT) careers and their deeply traditional but cosmopolitan Global South setting. Ultimately, the study critically investigates digital technologies which present inequitable experiences for women in Ghana.
Klotho and lean mass as novel cardiovascular risk factors in hemodialysis patients
Authors: Martins Ana Rita , Azeredo-Lopes Sofia , Pereira Sofia Azeredo , Moreira Inês , Weigert André Luíz
Published: September 2023

Background

Patients with chronic kidney disease (CKD) present a higher risk of cardiovascular (CV) morbidity and mortality compared with the general population. While there are several well-established traditional CV risk factors, few studies have addressed novel potential risk factors such as α-Klotho, asymmetric dimethylarginine (ADMA) and lean mass.

Methods

This was an observational, prospective, single-center, cohort study that included prevalent hemodialysis (online hemodiafiltration) adult patients. By univariate logistic regression models, univariate and multivariate Cox proportional hazards models, and Kaplan–Meier analysis, we evaluated the association between the levels of α-Klotho, ADMA and lean mass, with the risk of peripheral vascular disease (PVD), CV events and all-cause mortality in these patients.

Results

A total of 200 HD patients was included. We found that increased levels of log-α-Klotho were significantly associated with decreased odds of both PVD [odds ratio (OR) 0.521, 95% confidence interval (CI) 0.270–0.954, P = .034] and CV events (OR 0.415, 95% CI 0.203–0.790, P = .01), whereas increased levels of log-ADMA were only significantly associated with increased odds of PVD (OR 13.482, 95% CI 5.055–41.606, P < .001). We also found that the levels of log-α-Klotho (HR 0.357, 95% CI 0.140–0.906, P < .05) and lean mass (HR 0.187, 95% CI 0.042–0.829, P < .05), but not log-ADMA, were significantly associated with the risk of all-cause mortality, even after adjusting for possible confounding variables.

Conclusions

Novel long-term clinical associations were generated that support α-Klotho and lean mass as novel CV risk factors in hemodialysis patients.
Dobrava hantavirus and coinciding SARS-CoV-2 infection mimicking thrombotic microangiopathy and responding to a single dose of eculizumab
Authors: Aberger Simon , Kozakowski Nicolas , Proházka Zoltán , Pleininger Thomas , Salmhofer Hermann
Published: September 2023

The current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has refocused scientific interest on gaining insight into the pathophysiology of systemic viral diseases. Complement activation has been characterized as a driver of endothelial injury and microvascular thrombosis in acute respiratory distress syndrome as well as hantavirus hemorrhagic fever with renal syndrome. On this occasion, we wish to report a case of severe hantavirus disease with coinciding SARS-CoV-2 infection mimicking thrombotic microangiopathy with rapid response of inflammatory markers, hematologic parameters and proteinuria to eculizumab. These findings support a disease model of virus-associated endothelial injury involving alternative pathway complement activation. Future studies are needed to explore whether end organ damage can be mitigated by complement inhibition in life-threatening viral disease.
Estimation of large covariance matrices with mixed factor structures
Authors: Dai Runyu , Uematsu Yoshimasa , Matsuda Yasumasa
Published: September 2023

We extend the principal orthogonal complement thresholding (POET) framework by J. Fan, Y. Liao, and M. Mincheva (2013) to estimate large covariance matrices with a ‘mixed’ structure of observable and unobservable strong/weak factors, and we call this method the extended POET (ePOET). Especially, the weak factor structure allows the existence of slowly divergent eigenvalues of the covariance matrix that are frequently observed in real data. Under some mild conditions, we derive the uniform consistency of the proposed estimator for the cases with or without observable factors. Furthermore, several simulation studies show that the ePOET achieves good finite-sample performance regardless of data with strong, weak, or mixed factors structure. Finally, we conduct empirical studies to present the practical usefulness of the ePOET.
Testing a candidate meiotic drive locus identified by pool sequencing
Authors: Barbash Daniel A , Jin Bozhou , Wei Kevin H C , Dion-Côté Anne-Marie
Published: September 2023

Meiotic drive biases the transmission of alleles in heterozygous individuals, such that Mendel's law of equal segregation is violated. Most examples of meiotic drive have been discovered over the past century based on causing sex ratio distortion or the biased transmission of easily scoreable genetic markers that were linked to drive alleles. More recently, several approaches have been developed that attempt to identify distortions of Mendelian segregation genome wide. Here, we test a candidate female meiotic drive locus in Drosophila melanogaster, identified previously as causing a ∼54:46 distortion ratio using sequencing of large pools of backcross progeny. We inserted fluorescent visible markers near the candidate locus and scored transmission in thousands of individual progeny. We observed a small but significant deviation from the Mendelian expectation; however, it was in the opposite direction to that predicted based on the original experiments. We discuss several possible causes of the discrepancy between the 2 approaches, noting that subtle viability effects are particularly challenging to disentangle from potential small-effect meiotic drive loci. We conclude that pool sequencing approaches remain a powerful method to identify candidate meiotic drive loci but that genotyping of individual progeny at early developmental stages may be required for robust confirmation.
Application of near-infrared fluorescence imaging in theranostics of gastrointestinal tumors
Authors: Shi Nan-Qing , Cui Xin-Yuan , Zhou Cheng , Tang Ning , Cui Da-Xiang
Published: September 2023

Gastrointestinal cancers have become an important cause of cancer-related death in humans. Improving the early diagnosis rate of gastrointestinal tumors and improving the effect of surgical treatment can significantly improve the survival rate of patients. The conventional diagnostic method is high-definition white-light endoscopy, which often leads to missed diagnosis. For surgical treatment, intraoperative tumor localization and post-operative anastomotic state evaluation play important roles in the effect of surgical treatment. As a new imaging method, near-infrared fluorescence imaging (NIRFI) has its unique advantages in the diagnosis and auxiliary surgical treatment of gastrointestinal tumors due to its high sensitivity and the ability to image deep tissues. In this review, we focus on the latest advances of NIRFI technology applied in early diagnosis of gastrointestinal tumors, identification of tumor margins, identification of lymph nodes, and assessment of anastomotic leakage. In addition, we summarize the advances of NIRFI systems such as macro imaging and micro imaging systems, and also clearly describe the application process of NIRFI from system to clinical application, and look into the prospect of NIRFI applied in the theranostics of gastrointestinal tumors.
High levels of intra-strain structural variation in Drosophila simulans X pericentric heterochromatin
Authors: Courret Cécile , Larracuente Amanda M
Published: September 2023

Large genome structural variations can impact genome regulation and integrity. Repeat-rich regions like pericentric heterochromatin are vulnerable to structural rearrangements although we know little about how often these rearrangements occur over evolutionary time. Repetitive genome regions are particularly difficult to study with genomic approaches, as they are missing from most genome assemblies. However, cytogenetic approaches offer a direct way to detect large rearrangements involving pericentric heterochromatin. Here, we use a cytogenetic approach to reveal large structural rearrangements associated with the X pericentromeric region of Drosophila simulans. These rearrangements involve large blocks of satellite DNA—the 500-bp and Rsp-like satellites—which colocalize in the X pericentromeric heterochromatin. We find that this region is polymorphic not only among different strains, but between isolates of the same strain from different labs, and even within individual isolates. On the one hand, our observations raise questions regarding the potential impact of such variation at the phenotypic level and our ability to control for such genetic variability. On the other hand, this highlights the very rapid turnover of the pericentric heterochromatin most likely associated with genomic instability of the X pericentromere. It represents a unique opportunity to study the dynamics of pericentric heterochromatin, the evolution of associated satellites on a very short time scale, and to better understand how structural variation arises.
Bounding the localized to ductile transition in porous rocks: implications for geo-reservoirs
Authors: Meyer Gabriel G , Violay Marie
Published: September 2023

Porous rocks have long been the focus of intense research driven by their importance in our society as host to our most essential resources (oil, gas, water, geothermal energy, etc), yet their rheology remains poorly understood. With increasing depth, porous rocks transition from being brittle (dilational deformation leading to localized failure) to being ductile (homogeneous compactive flow, no failure). The transition between these two regimes is crucial for reservoir engineering. In fact, brittle, localized deformation of porous rocks is generally accompanied by permeability enhancement but also induced seismicity, while ductile deformation leads to aseismic permeability reduction. Decades of experimental work has shown that this transition is not sharp but rather spans a wide P, T domain, but to this day, no clear boundaries have been established. Here, we subjected pre-faulted samples of Volvic trachyandesite to increasing confining pressure, deforming the samples each pressure step and recording strain partitioning between off-fault bulk deformation and on-fault slip. For the first time, we show that the localized–ductile transition (LDT) in porous rocks is bound by the stress criterion σy  <  σf  <  σflow. Additionally we show that, in this regime, once both fault sliding and bulk flow are active, the partitioning of strain between the two can be described by the empirical ratio: $(\sigma _\mathrm{f}-\sigma _\mathrm{y})/(\sigma _\mathrm{flow}-\sigma _\mathrm{y}).$ Finally, we propose a critical stress representation that takes into account the existence of the LDT in porous rocks.
Outcome of Very Early Onset Inflammatory Bowel Disease Associated With Primary Sclerosing Cholangitis: A Multicenter Study From the Pediatric IBD Porto Group of ESPGHAN
Authors: Catassi Giulia , D’Arcangelo Giulia , Norsa Lorenzo , Bramuzzo Matteo , Hojsak Iva , Kolho Kaija-Leena , Romano Claudio , Gasparetto Marco , Di Giorgio Angelo , Hussey Seamus , Yerushalmy-Feler Anat , Turner Dan , Matar Manar , Weiss Batia , Karoliny Anna , Alvisi Patrizia , Tzivinikos Christos , Aloi Marina
Published: September 2023

Background

Whether primary sclerosing cholangitis related to inflammatory bowel disease (PSC-IBD) diagnosed before 6 years (ie, VEO-IBD) has a distinct phenotype and disease course is uninvestigated. We aimed to analyze the characteristics and natural history of VEO-PSC-IBD, compared with early and adolescent-onset PSC-IBD.

Methods

This is a multicenter, retrospective, case-control study from 15 centers affiliated with the Porto and Interest IBD group of ESPGHAN. Demographic, clinical, laboratory, endoscopic, and imaging data were collected at baseline and every 6 months. Inflammatory bowel disease–related (clinical remission, need for systemic steroids and biologics, and surgery) and PSC-related (biliary and portal hypertensive complications, need for treatment escalation and liver transplantation, cholangiocarcinoma, or death) outcomes were compared between the 2 groups.

Results

Sixty-nine children were included, with a median follow-up of 3.63 years (interquartile range, 1-11): 28 with VEO-PSC-IBD (23 UC [82%], 2 IBD-U [7%] and 3 [11%] CD), and 41 with PSC-IBD (37 UC [90%], 3 IBDU [7.5%] and 1 [2.5%] CD). Most patients with UC presented with pancolitis (92% in VEO-PSC-UC vs 85% in PSC-UC, P = .2). A higher number of patients with VEO-PSC-IBD were diagnosed with PSC/autoimmune hepatitis overlap syndrome than older children (24 [92%] vs 27 [67.5%] PSC-IBD, P = .03), whereas no other differences were found for PSC-related variables. Time to biliary strictures and infective cholangitis was lower in the VEO-PSC-IBD group (P = .01 and P = .04, respectively), while no difference was found for other outcomes. No cases of cholangiocarcinoma were reported.

Conclusions

Primary sclerosing cholangitis related to inflammatory bowel disease has similar baseline characteristics whether diagnosed as VEO-IBD or thereafter. A milder disease course in terms of biliary complications characterizes VEO-PSC-IBD.
Income growth, forecasting and stock valuation
Authors: Psychoyios Dimitris
Published: September 2023

Accepted by: Aris Syntetos

We show that using forecasts of a firm’s income growth in the context of stock valuation can lead to overpricing of the firm’s stock, which is consistent with ‘optimism bias’ reported among financial analysts. Firms with volatile earnings, high income growth and low systematic risk are prone to larger valuation errors. To address this issue, we develop a new estimator of the firm value that corrects for the bias from forecasting income growth. The new estimator is significantly superior to the traditional value estimator under various performance measures. To support managerial decision-making, we construct closed-form confidence intervals for the firm value and the implied cost of capital that account for uncertainty in income growth.
The Higher Structure of Unstable Homotopy Groups
Authors: Basu Samik , Blanc David , Sen Debasis
Published: September 2023

We construct certain unstable higher order homotopy operations indexed by the simplex categories of $\boldsymbol{\Delta }^{n}$ for $n\geq 2$, and prove that all elements in the homotopy groups of a wedge of spheres are generated under such operations by Whitehead products and the group structure. This provides a stronger unstable analogue of Cohen’s theorem on the decomposition of stable homotopy.
Genomic Epidemiology of Treponema pallidum and Circulation of Strains With Diminished tprK Antigen Variation Capability in Seattle, 2021–2022
Authors: Lieberman Nicole A P , Avendaño Carlos C , Bakhash Shah A K Mohamed , Nunley Ethan , Xie Hong , Giacani Lorenzo , Berzkalns Anna , Soge Olusegun O , Reid Tara B , Golden Matthew R , Greninger Alexander L
Published: September 2023

Background

The incidence of syphilis continues to increase in the United States, yet little is known about Treponema pallidum genomic epidemiology within American metropolitan areas.

Methods

We performed whole-genome sequencing and tprK deep sequencing of 28 T. pallidum–containing specimens, collected mostly from remnant Aptima swab specimens from 24 individuals from Seattle Sexual Health Clinic during 2021–2022.

Results

All 12 individuals infected with Nichols-lineage strains were men who have sex with men, while a specific SS14 cluster (mean, 0.33 single-nucleotide variant) included 1 man who has sex with women and 5 women. All T. pallidum strains sequenced were azithromycin resistant via 23S ribosomal RNA A2058G mutation. Identical T. pallidum genomic sequences were found in pharyngeal and rectal swab specimens taken concurrently from the same individuals. The tprK sequences were less variable between patient-matched specimens and between epidemiologically linked clusters. We detected a 528–base pair deletion in the tprK donor site locus, eliminating 9 donor sites, in T. pallidum genomes of 3 individuals with secondary syphilis, associated with diminution of TprK diversity.

Conclusions

We developed an end-to-end workflow for public health genomic surveillance of T. pallidum from remnant Aptima swab specimens. tprK sequencing may assist in linking cases beyond routine T. pallidum genome sequencing. T. pallidum strains with deletions in tprK donor sites currently circulate and are associated with diminished TprK antigenic diversity.
Environmental Surveillance for Salmonella Typhi and its Association With Typhoid Fever Incidence in India and Malawi
Authors: Uzzell Christopher B , Abraham Dilip , Rigby Jonathan , Troman Catherine M , Nair Satheesh , Elviss Nicola , Kathiresan Lalithambigai , Srinivasan Rajan , Balaji Veeraraghavan , Zhou Nicolette A , Meschke John Scott , John Jacob , Kang Gagandeep , Feasey Nicholas , Mohan Venkata Raghava , Grassly Nicholas C
Published: September 2023

Background

Environmental surveillance (ES) for Salmonella Typhi potentially offers a low-cost tool to identify communities with a high burden of typhoid fever.

Methods

We developed standardized protocols for typhoid ES, including sampling site selection, validation, characterization; grab or trap sample collection, concentration; and quantitative PCR targeting Salmonella genes (ttr, staG, and tviB) and a marker of human fecal contamination (HF183). ES was implemented over 12 months in a historically high typhoid fever incidence setting (Vellore, India) and a lower incidence setting (Blantyre, Malawi) during 2021–2022.

Results

S. Typhi prevalence in ES samples was higher in Vellore compared with Blantyre; 39/520 (7.5%; 95% confidence interval [CI], 4.4%–12.4%) vs 11/533 (2.1%; 95% CI, 1.1%–4.0%) in grab and 79/517 (15.3%; 95% CI, 9.8%–23.0%) vs 23/594 (3.9%; 95% CI, 1.9%–7.9%) in trap samples. Detection was clustered by ES site and correlated with site catchment population in Vellore but not Blantyre. Incidence of culture-confirmed typhoid in local hospitals was low during the study and zero some months in Vellore despite S. Typhi detection in ES.

Conclusions

ES describes the prevalence and distribution of S. Typhi even in the absence of typhoid cases and could inform vaccine introduction. Expanded implementation and comparison with clinical and serological surveillance will further establish its public health utility.
Epigenetic effects of ceftriaxone-resistant Neisseria gonorrhoeae FC428 mosaic-like sequences found in PenA sequences unique to Neisseria subflava and related species
Authors: Kanesaka Izumo , Ohno Akira , Morita Masahiro , Katsuse Akiko Kanayama , Morihana Takefumi , Ito Takamitsu , Takahashi Hiroshi , Kobayashi Intetsu
Published: September 2023

Objectives

The aim of this study was to explore the origin of the PenA mosaic amino acid sequence in the ceftriaxone-resistant Neisseria gonorrhoeae FC428 clone.

Methods

The penA sequences of 27 Neisseria subflava pharyngeal isolates were determined by the Sanger method and penA sequences of 52 isolates from nine Neisseria species were obtained from the NCBI database. Comparative analysis of each PenA sequence was performed by multiple sequence alignment using ClustalW.

In vitro resistance acquisition experiments were conducted to investigate the possibility of selection pressure by cefixime-induced amino acid substitution mutations in PenA.

Results

All N. subflava strains, including two with low susceptibility to expanded-spectrum cephalosporins (ESCs), possessed the majority of the PenA FC428 sequence. Furthermore, a number of strains, but not all, of closely related species of N. subflava showed similar results. PenA FC428 sequences were also found in some strains of distantly related species. No new mutations in the penA sequence were observed in colonies with increased MIC in in vitro resistance acquisition experiments.

Conclusions

This study provides strong evidence that the FC428 PenA mosaic sequence originated from N. subflava and related species among oral commensal Neisseria species. The results of in vitro resistance acquisition experiments also suggested that one of the PenA FC428-like sequence gene polymorphisms resulted in the expression of ESC resistance. Furthermore, many of the PenA FC428 mosaic sequences were thought to be involved in the so-called epistasis effect that regulates the expression of resistance, without directly contributing to the resistance level itself.
Impact of pretreatment low-abundance HIV-1 drug resistance on virological failure after 1 year of antiretroviral therapy in China
Authors: Li Miaomiao , Song Chang , Hu Jing , Dong Aobo , Kang Ruihua , Feng Yi , Xing Hui , Ruan Yuhua , Shao Yiming , Hong Kunxue , Liao Lingjie
Published: September 2023

Objectives

To assess the impact of pretreatment low-abundance HIV drug-resistant variants (LA-DRVs) on virological outcomes among ART-naive HIV-1-infected Chinese people who initiated ART.

Methods

A nested case–control study was conducted among HIV-1-infected individuals who had pretreatment drug resistance (PDR) genotypic results. Cases were defined as individuals with virological failure (HIV-1 RNA viral load ≥1000 copies/mL) after 1 year of ART, and controls were individuals from the same cohort whose viral load was less than 1000 copies/mL. Next-generation sequencing was used to identify low-abundance PDR mutations at detection thresholds of 10%, 2% and 1%. The mutant load was calculated by multiplying the abundance of HIV-1 drug-resistant variants by the pretreatment viral load. The impact of pretreatment low-abundance mutations on virological failure was estimated in logistic regression models.

Results

Participants (43 cases and 100 controls) were included in this study for the analysis. The proportion of participants with PDR was higher in cases than in controls at different detection thresholds (44.2% versus 22.0%, P = 0.007 at 10% threshold; 58.1% versus 31.0%, P = 0.002 at 2% threshold; 90.7% versus 69.0%, P = 0.006 at 1% threshold). Compared with participants without PDR, participants with ≥10% detectable PDR mutations were associated with an increased risk of virological failure (adjusted OR 8.0, 95% CI 2.4–26.3, P = 0.001). Besides this, individuals with pretreatment LA-DRVs (2%–9% abundance range) had 5-fold higher odds of virological failure (adjusted OR 5.0, 95% CI 1.3–19.6, P = 0.021). Furthermore, LA-DRVs at 2%–9% abundance resistant to NRTIs and mutants with abundance of ≥10% resistant to NNRTIs had a 4-fold and 8-fold risk of experiencing virological failure, respectively. It was also found that a mutant load of more than 1000 copies/mL was predictive of virological failure (adjusted OR 7.2, 95% CI 2.5–21.1, P = 0.0003).

Conclusions

Low-abundance PDR mutations ranging from 2% to 9% of abundance can increase the risk of virological failure. Further studies are warranted to define a clinically relevant threshold of LA-DRVs and the role of NRTI LA-DRVs.
Determination of Tilmicosin in Bovine, Swine, Chicken, and Turkey Tissues by Liquid Chromatography With Tandem Mass Spectrometry, Single-Laboratory Validation
Authors: Rodewald John Matt , Burnett Thomas J , Brunelle Sharon L , Ward Clive , Coleman Mark R
Published: September 2023

Background

An LC-MS/MS method was developed for determination and confirmation of tilmicosin in bovine, swine, chicken, and turkey tissues (liver, kidney, muscle, and skin/fat) and bovine milk.

Objective

The method was subjected to single-laboratory validation to establish method performance parameters.

Method

Animal tissues and bovine milk were fortified at four concentrations ranging from 0.5 times the lowest maximum residue limit (MRL) or tolerance to 2 times the highest MRL or tolerance considering the Codex and EU MRLs and the US tolerances in the various tissues and milk studied. Incurred tissues were analyzed to verify the precision of the method.

Results

The data demonstrated linearity of matrix-matched calibration curves using a weighted (1/×) regression. Recoveries varied from 83.3 to 107.1%. Repeatability precision (RSDr) ranged from 0.465 to 13.4% and intermediate precision (RSDi) ranged from 2.24 to 14.7% in fortified tissue. Repeatability of the method was verified in incurred tissues, ranging from 3.41 to 16.0%. The limits of detection and quantitation of the method are presented and vary by matrix. One confirmatory transition ion was examined across all matrixes and met US and EU criteria for mass spectrometry confirmation. The method was shown to be robust when small changes in method parameters were made, and stability of the analyte in fortified tissues, extracts, standard solutions, and matrix-matched standards was estimated.

Conclusions

The data satisfy the requirements of the AOAC Stakeholder Panel for Veterinary Drug Residue Methods for single-laboratory validation studies and the U.S. Food and Drug Administration Center for Veterinary Medicine Guidance for Industry #208 (VICH GL49).

Highlights

The LC-MS/MS method was demonstrated to be suitable for determination and confirmation of tilmicosin residues in bovine, swine, chicken, and turkey tissues and bovine milk based on Codex and EU MRLs and US tolerances.
Ecological succession of blow flies (Diptera: Calliphoridae) in the decomposition of pig carcasses in Cerrado areas of Brazil
Authors: Silva José Orlando de Almeida , Carvalho-Filho Fernando da Silva , Juen Leandro , Esposito Maria Cristina
Published: September 2023

This research aims to describe the process of ecological succession by associating the decomposition stages of pig carcasses with flies from the Calliphoridae family (Diptera). For this, 6 pig carcasses were exposed in Maranhão’s Cerrado, utilizing metal cages with sawdust trays to catch immature specimens and “suspended traps” to capture adults. Adults of the Hemilucilia benoisti Séguy, and Hemilucilia townsendi Shannon species were only associated with the swelling stage. Chrysomya megacephala (Fabricius) was associated with 2 stages (black putrefaction and fermentation). The species Chloroprocta idioidea (Robineau-Desvoidy), Chrysomya albiceps (Wiedemann), Cochliomyia macellaria (Fabricius), and Lucilia eximia (Wiedemann) were associated with 4 of the 5 stages of decomposition, the latter being the only 1 associated with the initial stage. The larvae abandoned the carcasses to pupate from the second stage of decomposition, with L. eximia being the only 1 leaving the carcasses in the swelling stage, and C. albiceps the only 1 associated with both the fermentation and dry stages. Our findings indicate that calliphorid species can help forensic investigators estimine the post-mortem interval of cadavers in situations similar to those detailed in this study. Since there was a link between adult and immature species and certain stages, they can be used as indicators in future forensic investigations.
Climatic factors regulate the assembly processes of abundant and rare microbial communities in desert soil
Authors: Sun Qiang , Li Hang-Yu , Li Kuan , Zhang Xiao-Qing , Shi Ya-Bo , Wu Yan-Tao , Li Xing , Li Zhi-Yong , Zhang Jing-Hui , Wang Li-Xin , Liang Cun-Zhu
Published: September 2023

Soil microorganisms, which include many rare taxa and a small number of abundant taxa, have different contributions to the ecosystem functions and services. High throughput sequencing technology was used to analyze the species composition of soil samples by DNA sequencing. Soil microorganisms were divided into abundant taxa and rare taxa to reveal their composition. Correlation analysis and random forest method were used to further analyze the influence of environmental factors on the community. Finally, the beta nearest taxon index (βNTI) based on the null model was used to elucidate the mechanisms underlying soil microbial community assembly. We found that, in desert soil, the community assembly of rare bacteria was almost entirely dominated by a homogeneous selection of deterministic processes. For comparison, stochastic processes had more pronounced effects on the abundant bacteria. However, both abundant and rare fungi exhibited similar patterns of community assembly, i.e. deterministic and stochastic processes jointly determined the assembly processes of fungal communities. We also observed that community assembly shifted from stochastic to deterministic processes with increasing mean annual precipitation (MAP) and mean annual temperature (MAT) for abundant bacteria. Conversely, for rare fungi, there was an inclination toward a shift from deterministic to stochastic processes with rising MAT. In conclusion, our findings provide compelling evidence that MAT and MAP regulate the community assembly process of abundant and rare microbial communities in desert soil. These findings establish a theoretical foundation for future investigations into the community structure and ecological functions of soil microorganisms.