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A three-dimensional feature extraction-based method for coal cleat characterization using X-ray μCT and its application to a Bowen Basin coal specimen

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 153-166页

作者： Yulai Zhang Matthew Tsang Mark Knackstedt michael Turner Shane Latham Euan Macaulay Rhys Pitchers ARC Training Centre for M3D Innovation Research School of PhysicsAustralian National UniversityCanberraACT2601Australia Department of Materials Physics Research School of PhysicsAustralian National UniversityCanberraACT2601Australia Anglo American Steelmaking Coal BrisbaneQLD4000Australia SCT Operations Pty Ltd. WollongongNSW2500Australia

Cleats are the dominant micro-fracture network controlling the macro-mechanical behavior of *** understanding of the spatial characteristics of cleat networks is therefore important to the coal mining *** fracture networks(DFNs)are increasingly used in engineering analyses to spatially model fractures at various *** reliability of coal DFNs largely depends on the confidence in the input cleat *** of these parameters can be made from image-based three-dimensional(3D)characterization of coal cleats using X-ray micro-computed tomography(m CT).One key step in this process,after cleat extraction,is the separation of individual cleats,without which the cleats are a connected network and statistics for different cleat sets cannot be *** this paper,a feature extraction-based image processing method is introduced to identify and separate distinct cleat groups from 3D X-ray m CT ***(filters)representing explicit cleat features of coal are built and cleat separation is successfully achieved by convolutional operations on 3D coal *** new method is applied to a coal specimen with 80 mm in diameter and 100 mm in length acquired from an Anglo American Steelmaking Coal mine in the Bowen Basin,Queensland,*** is demonstrated that the new method produces reliable cleat separation capable of defining individual cleats and preserving 3D topology after ***-parallel fractures are also identified and separated,which has his-torically been challenging to delineate and rarely reported.A variety of cleat/fracture statistics is measured which not only can quantitatively characterize the cleat/fracture system but also can be used for DFN ***,variability and heterogeneity with respect to the core axis are *** heterogeneity is observed and suggests that the representative elementary volume(REV)of the cleat groups for engineering purposes may be a complex problem requ

关键词： Cleat separation Cleat statistics Feature extraction Discrete fracture network(DFN)modeling

The energetics of cellular life transitions

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Life Metabolism 2024年第3期3卷 12-20页

作者： Anna S.Monzel michael Levin Martin Picard Department of Psychiatry Division of Behavioral MedicineCollege of Physicians and SurgeonsColumbia University Irving Medical CenterNew YorkNY 10032United States Department of Biology Tufts UniversityMedfordMA 02155United States Allen Discovery Center at Tufts University MedfordMA 02155United States Wyss Institute for Biologically Inspired Engineering Harvard UniversityBostonMA 02115United States Department of Neurology H.Houston Merritt CenterColumbia Translational Neuroscience InitiativeCollege of Physicians and SurgeonsColumbia University Irving Medical CenterNew YorkNY 10032United States New York State Psychiatric Institute New YorkNY 10032United States Robert N Butler Columbia Aging Center Columbia University Mailman School of Public HealthNew YorkNY 10032United States

Major life transitions are always difficult because change costs *** findings have demonstrated how mitochondrial oxidative phosphorylation(OxPhos)defects increase the energetic cost of living and that excessive integrated stress response(ISR)signaling may prevent cellular identity transitions during *** this perspective,we discuss general bioenergetic principles of life transitions and the costly molecular processes involved in reprograming the cellular hardware/software as cells shift *** energetic cost of cellular differentiation has not been directly quantified,representing a gap in *** propose that the ISR is an energetic checkpoint evolved to(i)prevent OxPhos-deficient cells from engaging in excessively costly transitions and(ii)allow ISR-positive cells to recruit systemic energetic resources by signaling via GDF15 and the brain.

关键词： energy mitochondria signaling pathway growth differentiation factor 15 energy balance development

Comparisons of oxbow lake fish assemblages in relation to bigheaded carp establishment in the lower White River, Arkansas

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Ecological Processes 2024年第1期13卷 188-205页

作者： michael A.Eggleton Cody J.Salzmann Joseph E.Kaiser Shannon C.F.Smith Department of Aquaculture and Fisheries University of Arkansas at Pine Bluff Arkansas Game and Fish Commission Virginia Institute of Marine Science

Background Since the late 1990s, bigheaded carps(largely silver carp [Hypophthalmichthys molitrix] but also bighead carp [H. nobilis]) have established throughout the lower Mississippi River basin. Using previously studied oxbow lakes in the lower White River basin, Arkansas, we compared current(2017, “post-carp” establishment) fish assemblages to historical(2002, “pre-carp” establishment) fish assemblages. Fish assemblages were comprehensively assessed using multiple gears, including boat electrofishing, mini-fyke nets, and experimental small-mesh gill *** T-tests suggested that fish assemblage indices of richness, diversity, evenness, and dominance were often greater(P 0.05) between the pre-carp and post-carp period with fish assemblages depicted using mini-fyke nets. Nonmetric multidimensional scaling analyses indicated that fish assemblages differed structurally between pre-carp and post-carp periods. Assemblage differences were linked to both small and large abundance changes for more than 20 species. Abundances of gizzard shad(Dorosoma cepedianum), emerald shiner(Notropis atherinoides), pugnose minnow(Opsopoeodus emiliae), crappies(Pomoxis spp.), bluegill(Lepomis macrochirus), orangespotted sunfish(L. humilis), and yellow bass(Morone mississippiensis) declined between the pre-carp and postcarp periods. Conversely, abundances of weed shiner(N. texanus), pallid shiner(Hybopsis amnis), longear sunfish(L. megalotis), buffalofishes(Ictiobus spp.), and gars(Lepisosteus spp.) generally increased during the same *** Although not possible to conclude assemblage shifts were entirely related to bigheaded carps due to the absence of an appropriate reference system where carps did not establish, the wide establishment of these carps is one of the most pervasive changes to have occurred in the lower White

关键词： Bigheaded carp Silver carp Aquatic nuisance species Fish assemblage Oxbow lake Large river

Dietary xylo‑oligosaccharides and arabinoxylans improved growth efficiency by reducing gut epithelial cell turnover in broiler chickens

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1325-1335页

作者： Carla Castro Shahram Niknafs Gemma Gonzalez‑Ortiz Xinle Tan michael R.Bedford Eugeni Roura Centre for Nutrition and Food Sciences Queensland Alliance for Agriculture and Food InnovationThe University of QueenslandSt LuciaQLD 4072Australia AB Vista MarlboroughWiltshire SN84ANUK

Background One of the main roles of the intestinal mucosa is to protect against environmental ***-mentation of xylo-oligosaccharides(XOS)is known to selectively stimulate the growth of beneficial intestinal bacteria and improve gut health and function in *** may have an impact on the integrity of the intestinal epithelia where cell turnover is critical to maintain the compatibility between the digestive and barrier *** aim of the study was to evaluate the effect of XOS and an arabinoxylan-rich fraction(AXRF)supplementation on gut func-tion and epithelial integrity in broiler *** A total of 128 broiler chickens(Ross 308)were assigned into one of two different dietary treatments for a period of 42 d:1)control diet consisting of a corn/soybean meal-based diet;or 2)a control diet supplemented with 0.5%XOS and 1%*** treatment was randomly distributed across 8 pens(n=8)with 8 chickens *** intake and body weight were recorded *** d 42,one male chicken per pen was selected based on aver-age weight and euthanized,jejunum samples were collected for proteomics *** Dietary XOS/AXRF supplementation improved feed efficiency(P<0.05)from d 1 to 42 compared to the con-trol *** analysis was used to understand the mechanism of improved efficiency uncovering 346 dif-ferentially abundant proteins(DAP)(Padj<0.00001)in supplemented chickens compared to the non-supplemented *** the jejunum,the DAP translated into decreased ATP production indicating lower energy expenditure by the tissue(e.g.,inhibition of glycolysis and tricarboxylic acid cycle pathways).In addition,DAP were associated with decreased epithelial cell differentiation,and migration by reducing the actin polymerization ***-ting the two main pathways together,XOS/AXRF supplementation may decrease around 19%the energy required for the maintenance of the gastrointestinal *** Dietary XOS/AXRF supplementation improved gr

关键词： Actin Arabinoxylans Broiler Cell turnover Energy metabolism Jejunum Xylo-oligosaccharides

Gastroesophageal signet ring cell carcinoma morbidity and mortality: A retrospective review

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1629-1636页

作者： Megan Grinlinton Chris Furkert Andrew Maurice Neville Angelo michael Booth Department of General Surgery North Shore HospitalAuckland 0620New Zealand Department of Pathology North Shore HospitalAuckland 0620New Zealand

BACKGROUND Upper gastrointestinal(GI)signet ring cell carcinomas(SRCC)confer a poor *** benefit of operative intervention for this patient group is contro-versial in terms of overall *** To investigate factors relating to survival in patients with upper GI *** A retrospective,tertiary,single-centre review of patients who were diagnosed with oesophageal,gastroesophageal junction and gastric SRCC was *** primary outcome was to compare mortality of patients who underwent operative management with those who had nonoperative ***-dary outcomes included assessing the relationship between demographic and histopathological factors,and *** One hundred and thirty-one patients were *** one-year survival for the operative group was 81%and for the nonoperative group was 19.1%.The five-year survival in the operative group was 28.6%vs 1.5%in the nonoperative *** difference in overall survival between groups was statistically significant(HR 0.19,95%CI(0.13-0.30),P<0.001).There was no difference in survival when ad-justing for age,smoking status or *** multivariate analysis,patients who underwent surgical management,those with a lower stage of disease,and those with a lower Charlson Comorbidity Index(CCI)had significantly improved *** Well-selected patients with upper GI SRCC appear to have reasonable medium-term survival following *** surgery to a carefully selected patient group may improve the outcome for this disease.

关键词： Signet ring cell carcinoma Gastric cancer Oesophageal cancer Poorly cohesive gastric cancer Diffuse gastric cancer

Two-stage corrective operation for the treatment of pes cavovarus in patients with spina bifida

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World Journal of Orthopedics 2024年第7期15卷 618-626页

作者： Anthony Mack Padgett Ezan Kothari michael J Conklin Department of Orthopedics Indiana UniversityIndianapolisIN 46202United States Department of Orthopaedic Surgery University of Alabama at BirminghamBirminghamAL 35233United States Department of Orthopedic Surgery Children’s of AlabamaBirminghamAL 35233United States

BACKGROUND Pes cavovarus has an estimated incidence of 8%-17%in patients with spina bifida(SB).The majority of the current literature on surgical treatment of cavovarus feet in children and adolescents includes a variety of *** are currently no case series describing a treatment algorithm for deformity correction in this specific patient *** authors of this study present the results of a retrospective case series performed to assess the radiographic outcomes of two-stage corrective surgery in patients with *** Retrospective chart review was performed on patients with SB with a diagnosis of pes cavovarus at a freestanding children’s hospital who underwent surgical correction of the *** were excluded for lack of two-stage corrective operation,nonambulatory status,lack of at least six months follow-up,and age>18 years at the time of *** resulted in a cohort of 19 *** analysis was performed on 11 feet that had a complete series of preoperative and postoperative weightbearing *** and postoperative radiographic outcome measurements were compared using a two-sample *** Significant changes between the preoperative and postoperative measurements were seen in Meary’s angle,the anteroposterior talo-first metatarsal(AP TMT1)angle,and the talonavicular *** values of Meary’s angle were 17.9±13.1 preoperatively and 4.7±10.3 postoperatively(P=0.016).Mean AP TMT1 angle was 20.6±15.1 preoperatively and 9.3±5.5 postoperatively(P=0.011).Mean talonavicular coverage values were-10.3±9.6 preoperatively and-3.8±10.1 postoperatively(P=0.025).CONCLUSION The two-stage corrective procedure demonstrated efficacy in correcting cavovarus deformity in patients with *** should strongly consider employing the staged surgical algorithm presented in this manuscript for management of these patients.

关键词： Cavovarus Spina bifida Osteotomy Plantar release Radiographs Pediatrics

A GHz chirped amplitude-modulated laser for high-contrast plasma gratings

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High Power Laser Science and Engineering 2024年第1期12卷 74-83页

作者： michael Valdman Amir Hen Gilad Marcus Applied Physics Institute Hebrew University of JerusalemJerusalemIsrael

The generation and control of large amplitude plasma gratings and other plasma structures is of paramount importance for the realization of plasma photonics. Autoresonant excitation of such structures by means of chirped amplitude-modulated lasers has been recently discussed and analyzed theoretically. Here we discuss the parameter space for the realization of such a scheme and describe the laser system that was built towards this goal. We also expand our earlier theoretical study to account for the more realistic case of a moderately focused laser beam, instead of the simplified plane wave approximation.

关键词： amplitude modulation high-frequency modulation autoresonance ion acoustic wave

Emerging structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease

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Neural Regeneration Research 2025年第1期20卷 174-180页

作者： Yinglong Miao michael S.Wolfe Computational Medicine Program and Department of Pharmacology University of North Carolina–Chapel HillChapel HillNCUSA Department of Medicinal Chemistry University of KansasLawrenceKSUSA

γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface *** inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-Secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as ***,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-*** this review,we focus on recent studies of structural dynamic mechanisms ofγ-*** mechanisms,including the“Fit-Stay-Trim,”“Sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics *** an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental *** approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-*** addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is ***,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations

关键词： Alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics Notch

Anatomic location of the first dorsal extensor compartment for surgical De-Quervain’s tenosynovitis release:A cadaveric study

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World Journal of Orthopedics 2024年第4期15卷 379-385页

作者： Aditya Thandoni William Nicholas Yetter Steven michael Regal Department of Orthopaedic Surgery Allegheny Health NetworkPittsburghPA 15212United States

BACKGROUND De-Quervain’s tenosynovitis is a disorder arising from the compression and irritation of the first dorsal extensor compartment of the *** who fail conservative treatment modalities are candidates for surgical ***,risks with surgery include damage to the superficial radial nerve and an incomplete release due to inadequate ***,there is a paucity of literature demonstrating the exact anatomic location of the first dorsal extensor compartment in reference to surface ***,this cadaveric study was performed to determine the exact location of the first extensor compartment and to devise a reliable surgical incision to prevent *** To describe the location of the first dorsal compartment in relation to bony surface landmarks to create replicable surgical *** Six cadaveric forearms,including four left and two right forearm specimens were *** were performed by a single fellowship trained upper extremity orthopaedic *** of the first dorsal compartment from landmarks such as Lister’s tubercle,the wrist crease,and the radial styloid were *** variables studied included the presence of the superficial radial nerve overlying the first dorsal compartment,additional compartment subsheaths,number of abductor pollicis longus(APL)tendon slips,and the presence of a *** Distance from the radial most aspect of the wrist crease to the extensor retinaculum was 5.14 mm±0.80 *** distance from Lister’s tubercle to the distal aspect of the extensor retinaculum was 13.37 mm±2.94 ***’s tubercle to the start of the first dorsal compartment was 18.43 mm±2.01 *** radial styloid to the initial aspect of the extensor retinaculum measured 2.98 mm±0.99 *** retinaculum length longitudinally on average was 26.82 mm±3.34 *** cadaveric forearms had separate extensor pollicis brevis *** average number of APL tendon slips was th

关键词： De-Quervain’s tenosynovitis First extensor compartment Cadaveric study Superficial radial nerve Radial styloid Lister’s tubercle