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Owing to the extreme hardness and toughness of sintered silicon nitride (Si 3 N 4 ), the material is used in high stress and/or temperature applications such bearings, turbines, and combustion engines. Unfortunately, the same properties which make it ideal for use also make it particularly difficult to machine -- microcracks, inclusions and spalling are all common. While prior research has shown that it is possible to grind sintered Si 3 N 4 without inducing surface damage so long as material is removed entirely under ductile flow, but grind forces associated with ductile Si 3 N 4 material flow are so small as to render the material removal rate (MRR) impractical. Prior researchers have attempted to solve the MRR problem through laser-assisted machining. Laser ablation, by inducing a steep thermal gradient, weakens material through surface and subsurface cracks. Grinding of fractured weakened Si 3 N 4 has been done at upwards of 50 % higher MRR. There are, however, issues with laser ablation, which prevent its widespread use. Laser ablation severely disrupts the microstructure of Si 3 N 4 . Because cracks propagate along and through grain boundaries, the irregular morphology makes accurately predicting crack growth from ablation and during subsequent grinding highly problematic. In this proof-of-concept work, researchers determined that it is possible to irradiation weaken Si 3 N 4 without cracking it, and the material can be ground defect-free at a highly productive MRR. Findings suggest present laser-assisted machining methods which fracture weaken Si 3 N 4 prior to grinding may not be the best way to maximize MRR., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Dr. Craig Seidelson reports financial support was provided by 10.13039/100019542Timken Foundation Center for Precision Manufacturing, (© 2024 Published by Elsevier Ltd.)

Mycobacterium orygis is a member of the Mycobacterium tuberculosis complex (MTBC) and causes tuberculosis in a variety of animals, including humans in South Asia. Here, we describe the clinical features associated with 8 human cases of whole genome sequence (WGS) confirmed M. orygis from a tertiary care hospital in South India during 2018-2019. The patient ages ranged from 9 to 51 years, with 5 females and 3 males included. All the patients had extrapulmonary disease with 2 having concomitant pulmonary involvement. Clinical improvement was documented after a full course of anti-tuberculosis therapy in 6 cases for whom follow-up was available. Taken together, the results show that M. orygis causes human tuberculosis in India, with a predominant extrapulmonary disease. Standardized molecular assays of this emerging member of the MTBC are needed to provide further information on the frequency of M. orygis infection in India and other countries where it is found in livestock and domestic wildlife., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

Background: Although therapeutic hypothermia reduces death or disability after neonatal encephalopathy in high-income countries, its safety and efficacy in low-income and middle-income countries is unclear. We aimed to examine whether therapeutic hypothermia alongside optimal supportive intensive care reduces death or moderate or severe disability after neonatal encephalopathy in south Asia., Methods: We did a multicountry open-label, randomised controlled trial in seven tertiary neonatal intensive care units in India, Sri Lanka, and Bangladesh. We enrolled infants born at or after 36 weeks of gestation with moderate or severe neonatal encephalopathy and a need for continued resuscitation at 5 min of age or an Apgar score of less than 6 at 5 min of age (for babies born in a hospital), or both, or an absence of crying by 5 min of age (for babies born at home). Using a web-based randomisation system, we allocated infants into a group receiving whole body hypothermia (33·5°C) for 72 h using a servo-controlled cooling device, or to usual care (control group), within 6 h of birth. All recruiting sites had facilities for invasive ventilation, cardiovascular support, and access to 3 Tesla MRI scanners and spectroscopy. Masking of the intervention was not possible, but those involved in the magnetic resonance biomarker analysis and neurodevelopmental outcome assessments were masked to the allocation. The primary outcome was a combined endpoint of death or moderate or severe disability at 18-22 months, assessed by the Bayley Scales of Infant and Toddler Development (third edition) and a detailed neurological examination. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, NCT02387385., Findings: We screened 2296 infants between Aug 15, 2015, and Feb 15, 2019, of whom 576 infants were eligible for inclusion. After exclusions, we recruited 408 eligible infants and we assigned 202 to the hypothermia group and 206 to the control group. Primary outcome data were available for 195 (97%) of the 202 infants in the hypothermia group and 199 (97%) of the 206 control group infants. 98 (50%) infants in the hypothermia group and 94 (47%) infants in the control group died or had a moderate or severe disability (risk ratio 1·06; 95% CI 0·87-1·30; p=0·55). 84 infants (42%) in the hypothermia group and 63 (31%; p=0·022) infants in the control group died, of whom 72 (36%) and 49 (24%; p=0·0087) died during neonatal hospitalisation. Five serious adverse events were reported: three in the hypothermia group (one hospital readmission relating to pneumonia, one septic arthritis, and one suspected venous thrombosis), and two in the control group (one related to desaturations during MRI and other because of endotracheal tube displacement during transport for MRI). No adverse events were considered causally related to the study intervention., Interpretation: Therapeutic hypothermia did not reduce the combined outcome of death or disability at 18 months after neonatal encephalopathy in low-income and middle-income countries, but significantly increased death alone. Therapeutic hypothermia should not be offered as treatment for neonatal encephalopathy in low-income and middle-income countries, even when tertiary neonatal intensive care facilities are available., Funding: National Institute for Health Research, Garfield Weston Foundation, and Bill & Melinda Gates Foundation., Translations: For the Hindi, Malayalam, Telugu, Kannada, Singhalese, Tamil, Marathi and Bangla translations of the abstract see Supplementary Materials section., Competing Interests: Declaration of interests JW reports a grant from the National Institutes for Health (number 1R21HD093563-01) outside the submitted work. RP reports personal fees from UCB and Kephala outside the submitted work. All other authors declare no competing interests., (Copyright © 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background: Mosquitoes biolarvicides remain the most important method for mosquito control. The previous studies have shown Aspergillus sp. -expressed larvicidal properties against mosquito species. The present study evaluated larvicidal and histopathological effect of an endophytic fungus Aspergillus tamarii isolated from theCactus stem ( Opuntia ficus-indica Mill) ., Method: The molecular identification of isolated A. tamarii was done by PCR amplification (5.8s rDNA) using a universal primer (ITS-1 and ITS-2). The secondary metabolites of A. tamarii was tested for larvicidal activity against Aedes aegypti and Culex quinquefasciatus . Larvicidal bioassay of different concentrations (- 100, 300, 500, 800 and 1000 μg/mL) isolated extracts were done according to the modified protocol. Each test included a set of control groups (i.e. DMSO and distilled water). The lethal concentrations (LC 50 and LC 90 ) were calculated by probit analysis. Experimental monitoring duration was 48 h., Results: The ethyl acetate extract from A. tamarii fungus resulted - excellent mosquitocidal effect against Ae. aegypti and Cx. quinquefasciatus mosquitoes, with least LC 50 and LC 90 values. -After 48 h, the Ae. aegypti expressed better results (LC 50 = 29.10, 18.69, 16.76, 36.78 μg/mL and the LC 90 = 45.59, 27.66, 27.50, 54.00 μg/mL) followed by Cx. quinquefaciatus (LC 50 = 3.23, 24.99, 11.24, 10.95 μg/mL and the LC 90 = 8.37, 8.29, 21.36, 20.28 μg/mL). The biochemical level of A. tamarii mycelium extract on both larvae was measured and the results shown a dose dependent activity on the level of AchE, α- and β-carboxylesterase assay. Gas Chromatography and Mass Spectroscopy (GC-MS) profile of A. tamarii extract reflected three compounds i.e. preg-4-en-3-one, 17. α-hydroxy-17. β-cyano- (7.39%), trans-3-undecene-1,5-diyne (45.77%) and pentane, 1,1,1,5-tetrachloro- (32.16%) which which might had attributed to larvae mortality., Conclusion: The findings of - present study shows that the use of endophytic A. tamarii fungal metabolites for control of dengue and filariasis vectors is promising and needs a semifield and small scale filed trials., (© 2020 The Author(s).)

Background: Zoonotic tuberculosis is defined as human infection with Mycobacterium bovis . Although globally, India has the largest number of human tuberculosis cases and the largest cattle population, in which bovine tuberculosis is endemic, the burden of zoonotic tuberculosis is unknown. The aim of this study was to obtain estimates of the human prevalence of animal-associated members of the Mycobacterium tuberculosis complex (MTBC) at a large referral hospital in India., Methods: We did a molecular epidemiological surveillance study of 940 positive mycobacteria growth indicator tube (MGIT) cultures, collected from patients visiting the outpatient department at Christian Medical College (Vellore, India) with suspected tuberculosis between Oct 1, 2018, and March 31, 2019. A PCR-based approach was applied to subspeciate cultures. Isolates identified as MTBC other than M tuberculosis or as inconclusive on PCR were subject to whole-genome sequencing (WGS), and phylogenetically compared with publicly available MTBC sequences from south Asia. Sequences from WGS were deposited in the National Center for Biotechnology Information Sequence Read Archive, accession number SRP226525 (BioProject database number PRJNA575883)., Findings: The 940 MGIT cultures were from 548 pulmonary and 392 extrapulmonary samples. A conclusive identification was obtained for all 940 isolates; wild-type M bovis was not identified. The isolates consisted of M tuberculosis (913 [97·1%] isolates), Mycobacterium orygis (seven [0·7%]), M bovis BCG (five [0·5%]), and non-tuberculous mycobacteria (15 [1·6%]). Subspecies were assigned for 25 isolates by WGS, which were analysed against 715 MTBC sequences from south Asia. Among the 715 genomes, no M bovis was identified. Four isolates of cattle origin were dispersed among human sequences within M tuberculosis lineage 1, and the seven M orygis isolates from human MGIT cultures were dispersed among sequences from cattle., Interpretation: M bovis prevalence in humans is an inadequate proxy of zoonotic tuberculosis. The recovery of M orygis from humans highlights the need to use a broadened definition, including MTBC subspecies such as M orygis , to investigate zoonotic tuberculosis. The identification of M tuberculosis in cattle also reinforces the need for One Health investigations in countries with endemic bovine tuberculosis., Funding: Bill & Melinda Gates Foundation, Canadian Institutes for Health Research., (© 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.)

The Atlantic-Gaspésie caribou ( Rangifer tarandus caribou ) population is a small isolated relict herd considered endangered according to the Canadian Species at Risk Act (SARA). This population has low recruitment and survival rates but the potential role of parasites on individual fitness is unknown. In this context, we explored the parasite status of this population with the aim of 1) assessing the occurrence and intensity of parasite infections and the spatial, temporal and individual variations, 2) quantifying parasite richness and investigating factors such as sex and host body condition that may be associated with this variable and 3) evaluating the effects of parasite infections on survival in the Atlantic-Gaspésie caribou population. We examined fecal samples from 32 animals captured in 2013-2014 for eggs, oocysts and larvae of parasites and detected 7 parasite species: dorsal-spined larvae protostrongylids, presumably Parelaphostrongylus andersoni based on PCR identification of a subset, Nematodirus odocoilei and other unidentified Strongyles, Trichuris sp., Capillaria sp., Moniezia sp. and Eimeria sp. For each caribou, mean parasite species richness was 1.8 ± 1.1 (SD). Sex, body condition, year and capture location did not explain parasite prevalence, intensity of infection or richness except for intensity of infection of Capillaria sp. that was positively influenced by body condition. Parasites did not influence survival although mortality was higher for males than for females. We suggest that the relatively low and common gastrointestinal and protostrongylid parasite infections will not be a short-term threat leading to extinction.

The Protostrongylidae is a diverse family of nematodes capable of causing significant respiratory and neuromuscular disease in their ungulate and lagomorph hosts. Establishing the species diversity and abundance of the protostrongylid fauna has been hindered because the first stage larvae, commonly referred as dorsal spined larvae (DSL), that are shed in the feces are morphologically very similar among several genera. We aimed to determine the protostrongylid diversity and distribution in caribou ( Rangifer tarandus groenlandicus and R. t. pearyi ) in the central and high Canadian Arctic. We first developed, tested and validated a morphological diagnostic guide for the DSL of two important protostrongylids, Parelaphostrongylus andersoni and Varestrongylus eleguneniensis, and then applied this guide to determine the prevalence and intensity of infection of these parasites in fecal samples from 242 caribou. We found that DSL of V. eleguneniensis and P. andersoni can be differentiated morphologically based on the structural differences at the caudal extremity. The presentation and morphology of the dorsal spine, and caudoventral bulging at the start of the tail extension were identified as the key identifying features. The two species were found in caribou on the arctic mainland and southern Victoria Island in single and co-infections, but the prevalence and intensity of infection was low. No protostrongylids were detected in caribou from the high arctic islands. Through this study, we provide a simple, efficient, and robust method to distinguish the DSL of the two protostrongylids, and present the current status of infection in different herds of caribou of the central Canadian Arctic. We report new geographic and host records for P. andersoni infection in Dolphin and Union caribou herd.

Umingmakstrongylus pallikuukensis and Varestrongylus eleguneniensis are the two most common protostrongylid nematodes infecting muskoxen in the North American Arctic and Subarctic. First stage larvae (L1) of these lungworms have considerable morphological similarity that makes their differential diagnosis very difficult. Using light microscopy, we studied in detail the L1 of these two species and identified the key differences in morphological and morphometric attributes. Thirty L1 of each species from naturally infected muskox were heat-killed and then assessed for morphological and morphometric features that could be used for species-level differentiation. Key differentiating features include: length and morphology of the tail extension, curvature of the body, ventral post-anal transverse cuticular striations, and total body length. A laboratory guide for differentiation of L1 based on these species-specific characters was prepared and used by an experienced observer to identify an additional 35 L1 extracted from a different set of fecal samples from free-ranging muskoxen with mixed infections. The identities of these L1 were confirmed by sequence analysis of the ITS-2 region of the nuclear ribosomal DNA. Accuracy of morphological identification was 100 percent, reflecting the reliability of the proposed guide for differentiation. Using the guide, three minimally trained lab assistants each fixed and accurately identified 10 of 10 randomly selected L1. Ability to morphologically differentiate these facilitates the monitoring of overlapping range expansion of both parasites in the Canadian Arctic. Studies enabling species-level parasite identification are also critical for defining biodiversity, detecting mixed infections, and understanding host-parasite interactions. Morphological identification is a simple, reliable and cost-effective alternative to labor and equipment intensive molecular methods and can easily be performed in low resource settings.

Histological lesions associated with Eucoleus sp. infection of the non-glandular stomach were discovered in a wild, urban population of Norway rats (Rattus norvegicus) trapped over a 1-year period in Vancouver, Canada. Four distinct categories of histological lesions in the non-glandular stomach were identified in association with infection in a sample of 183 rats. The apparent prevalence of Eucoleus sp. in the upper gastrointestinal tract (ventral tongue, oropharynx, esophagus and non-glandular stomach) was 43.1% (79/183). Infection with Eucoleus sp. was significantly associated with hyperkeratosis, mucosal hyperplasia, keratin pustules and submucosal inflammation in the non-glandular stomach (P < 0.05). Eucoleus sp. infection and/or related stomach pathology was present in 135/183 (73.8%) of rats. Statistical analysis showed the odds of being affected by Eucoleus sp. or associated stomach pathology were greater in heavier (OR = 1.06, 95% CI = 1.00-1.12) and sexually mature rats (OR = 4.64, 95% CI = 1.23-17.10). Eucoleus sp. infection is common in wild rats in Vancouver and induces substantial host response. The impact of Eucoleus sp. and associated lesions on the health of individual rats and the population as a whole remains to be investigated.

Parelaphostrongylus andersoni is a muscle-dwelling protostrongylid nematode that infects caribou and white-tailed deer across North America, and can cause significant muscular and pulmonary pathology in these species. We collected 44 fecal samples from semi-domesticated reindeer (Rangifer tarandus tarandus) from the Kakarak herd of western Seward Peninsula, Alaska, USA. This herd has no record of historical contact and extremely limited possibility of contemporary contact with native Grant's caribou (Rangifer tarandus granti) of the Western Arctic herd. Fecal samples were processed using the Baermann technique, and 22.7% (n = 10) were positive for protostrongylid dorsal-spined larvae (DSL). Genomic DNA extracted from individual DSL from each of the ten positive reindeer (total of 48 DSL) was amplified by PCR targeting the ITS-2 region of ribosomal RNA. Forty of 48 DSL were successfully sequenced and confirmed as P. andersoni and one representative sequence for each of the ten positive samples was deposited in GenBank. No other protostrongylids, including Varestrongylus sp., presumed to be widespread across caribou range, and Elaphostrongylus rangiferi, which could have been introduced with reindeer from Eurasia, were detected in these samples. P. andersoni is likely widespread among introduced reindeer in Alaska, potentially causing subtle but deleterious effects with negative economic impacts on commercial herding activities.