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International Journal of Mining Science and Technology 2021年第3期31卷 365-375页

作者： alessandro medolago Stefano Melzi Tesmec S.p.A. Grassobbio 24050Italy Department of Mechanics Politecnico di MilanoMilano 20156Italy

The discontinuous nature of rock cutting can easily cause unwanted vibrations in the structure of a surface miner.If these vibrations are not properly addressed,the related stress cycles can gradually damage the chassis resulting in fatigue failures.These events can seriously undermine the safety of operators and digging operations may be stopped for days,with an obvious economic impact.This work presents an analysis of the dynamics of a surface miner,focusing on the interaction between cutting machine dynamics and cutting forces,which is a new approach for this type of machine.For this purpose,the authors developed a numerical model of the cutting process made up of(1)a multi-body model of the cutting machine,which takes into account the chassis's flexibility;(2)a model of the rotating cutting head;and(3)a model of the interaction between the cutting head and rock,based on Shao's model.The model was compared with experimental results and then used to investigate the effects of cutting speed and cutting depth on the machine dynamics.

关键词： Surface miner Flexible multi-body model Validation Cutting forces Chassis vibrations

Pediatric stricturing Crohn's disease

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World Journal of Gastroenterology 2024年第12期30卷 1651-1654页

作者： alessandro Boscarelli Matteo Bramuzzo Department of Pediatric Surgery and Urology Institute for Maternal and Child Health-IRCCS“Burlo Garofolo”Trieste 34137Italy Department of Gastrointestinal Endoscopy and Nutrition Institute for Maternal and Child Health-IRCCS"Burlo Garofolo"Trieste 34137Italy

Crohn’s disease(CD)is a chronic inflammatory disease of the digestive tract.The incidence of pediatric CD is increasing and is currently 2.5-11.4 per 100000 world-wide.Notably,approximately 25%of children with CD develop stricturing CD(SCD)that requires intervention.Symptomatic stricturing diseases refractory to pharmacological management frequently require non-pharmacological interventions.Non-pharmacological therapeutic strategies include endoscopic balloon dilatation,stricturoplasty,and surgical resection of the strictured seg-ment.However,strictures tend to recur postoperatively regardless of treatment modality.The lifetime risk of surgery in patients with childhood SCD remains at 50%-90%.Thus,new and emerging strategies,advanced diagnostic tools,and minimally invasive approaches are under investigation to improve the outcomes and overall quality of life of pediatric patients with SCD.

关键词： Stricturing Crohn’s disease Pediatrics Insights Future perspectives

Conformational dynamics as an intrinsic determinant of prion protein misfolding and neurotoxicity

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Neural Regeneration Research 2024年第10期19卷 2095-2096页

作者： alessandro Cembran Pedro Fernandez-Funez Department of Chemistry and Biochemistry University of Minnesota DuluthDuluthMNUSA Department of Biomedical Sciences University of Minnesota Medical SchoolDuluth CampusDuluthMNUSA

The prion protein(PrP) is the key molecular and pathological mediator of prion diseases,a heterogeneous group of brain disorders with fatal outcomes.Prion diseases are rare but deserve special attention because of their unique familial,sporadic,and transmissible etiologies,all caused by a single agent:misfolded conformations of PrP.

关键词： folding intrinsic dynamics

Non-anatomical liver resection for hepatocellular carcinoma:the SegSubTe classification to overcome the problem of heterogeneity

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 265-271页

作者： Mattia Garancini alessandro Fogliati Mauro alessandro Scotti Cristina Ciulli Francesca Carissimi Antonio Rovere Luca Gianotti Fabrizio Romano Unit of Hepatobiliopancreatic Surgery Department of SurgeryASST-MonzaSan Gerardo HospitalUniversity of Milano-Bicoccavia Pergolesi 33MonzaMB 20052Italy Interventional Radiology Department of RadiologyASST-MonzaSan Gerardo HospitalMilano-Bicocca Universityvia Pergolesi 33MonzaMB 20052Italy

Background:The superiority of anatomical resection(AR)vs.non-anatomical resection(NAR)in the surgical management of hepatocellular carcinoma(HCC)is debated.ARs are well-defined procedures,whereas the lack of NAR standardization results in heterogeneous outcomes.This study aimed to introduce the SegSubTe classification for NAR detailing the appropriateness of the level of surgical section of the Glissonean pedicles feeding the tumor.Methods:A single-center retrospective analysis of pre-and postoperative imaging of consecutive patients treated with NAR for single HCC between 2012 and 2020 was conducted.The quality of surgery was assessed classifying the type of vascular supply and the level of surgical section(segmental,subsegmental or terminal next to the tumor)of vascular pedicles feeding the HCCs;then,the population was divided in“SegSubTe-IN”or“SegSubTe-OUT”groups,and the tumor recurrence and survival were analyzed.Results:Ninety-seven patients who underwent NAR were included;76%were SegSubTe-IN and 24%were SegSubTe-OUT.Total disease recurrence,local recurrence and cut-edge recurrence in the SegSubTe-IN vs.SegSubTe-OUT groups were 50%vs.83%(P=0.006),20%vs.52%(P=0.003)and 16%vs.39%(P=0.020),respectively.SegSubTe-OUT odds ratio for local recurrence was 4.1 at univariate regression analysis.One-,three-,and five-year disease-free survival rates in the SegSubTe-IN vs.SegSubTe-OUT groups were 81%,58%and 35%vs.46%,21%and 11%,respectively(P<0.001).Conclusions:The SegSubTe classification is a useful tool to stratify and standardize NAR for HCC,aiming at improving long-term oncological outcomes and reducing the heterogeneity of quality of NAR for HCC.

关键词： Hepatocellular carcinoma Intraoperative ultrasound Liver surgery Computed tomography Surgical procedure

Beyond functional MRI signals:molecular and cellular modifiers of the functional connectome and cognition

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Neural Regeneration Research 2024年第5期19卷 937-938页

作者： Lorenzo Pini alessandro Salvalaggio Maurizio Corbetta Padova Neuroscience Center University of PadovaItaly Veneto Institute of Molecular Medicine VIMMPadovaItaly Department of Neuroscience University of PadovaItaly

Our brain is constantly active.Even at rest,the brain carries out essential functions such as maintenance of resting potentials,subthreshold synaptic activity,and spiking activity related to information processing.This resting activity can be assessed with several in vivo tools,such as resting-state functional magnetic resonance imaging.This technique measures subtle changes in blood flow,volume,and oxygenation that occur over time.Although vascular in nature,resting-state functional magnetic resonance imaging is considered a reliable proxy of neural activity and several studies have shown that the brain is functionally divided into interacting neural networks called the“functional connectome”.

关键词： functional neural measures

A comprehensive review on the processing-property relationships of laser strengthened magnesium

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Journal of Magnesium and Alloys 2024年第1期12卷 1-34页

作者： alessandro M.Ralls Aaksheta Agnel Pradeep L.Menezes Department of Mechanical Engineering University of Nevada RenoRenoNV 89557United States

Among the existing series of softer metals,magnesium(Mg)has attracted much attention due to its impressive strength-to-weight ratio.However,due to its ease of deformability,Mg tends to suffer from rapid degradation in a wide variety of abrasive and electrochemical environments.One method of improving its surface properties is through surface modification techniques.Among the existing techniques,laser shock peening(LSP)has been one of the most widely utilized processes due to its surface-hardening-like effects.Despite this understanding,a comprehensive review has yet to exist that encapsulates the strengthening mechanism of LSP for Mg and its influence in degradation environments.This review aims to encapsulate the existing research around the LSP field for Mg.Specifically,an understanding of the surface-strengthening effects in relation to its mechanical,tribological,corrosion,and tribo-corrosion characteristics is elucidated.Additionally,the feasibility of LSP for Mg materials in critical industries is also discussed.Through this work,a novel understanding of LSP for Mg can be understood,which can provide a future direction for research in this field.

关键词： Laser shock peening Magnesium Surface deformation Tribology Microstructure

Spark Plasma Sintering of Mg-based Alloys:Microstructure,Mechanical Properties,Corrosion Behavior,and Tribological Performance

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Journal of Magnesium and Alloys 2024年第2期12卷 405-442页

作者： alessandro M.Ralls Mohammadreza Daroonparvar Pradeep L.Menezes Department of Mechanical Engineering University of Nevada RenoRenoNV89557United States

Within the past ten years,spark plasma sintering(SPS)has become an increasingly popular process for Mg manufacturing.In the SPS process,interparticle diffusion of compressed particles is rapidly achieved due to the concept of Joule heating.Compared to traditional and additive manufacturing(AM)techniques,SPS gives unique control of the structural and microstructural features of Mg components.By doing so,their mechanical,tribological,and corrosion properties can be tailored.Although great advancements in this field have been made,these pieces of knowledge are scattered and have not been contextualized into a single work.The motivation of this work is to address this scientific gap and to provide a groundwork for understanding the basics of SPS manufacturing for Mg.To do so,the existing body of SPS Mg literature was first surveyed,with a focus on their structural formation and degradation mechanisms.It was found that successful Mg SPS fabrication highly depended on the processing temperature,particle size,and particle crystallinity.The addition of metal and ceramic composites also affected their microstructural features due to the Zener pinning effect.In degradative environments,their performance depends on their structural features and whether they have secondary phased composites.In industrial applications,SPS'd Mg was found to have great potential in biomedical,hydrogen storage,battery,automotive,and recycling sectors.The prospects to advance the field include using Mg as a doping agent for crystallite size refinement and using bulk metallic Mg-based glass powders for amorphous SPS components.Despite these findings,the interactions of multi-composites on the processing-structure-property relationships of SPS Mg is not well understood.In total,this work will provide a useful direction in the SPS field and serve as a milestone for future Mg-based SPS manufacturing.

关键词： Spark plasma sintering Magnesium alloys Nanocrystalline Tribology Mechanical properties Corrosion

Alcohol associated liver disease and bariatric surgery:Current perspectives and future directions

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 650-657页

作者： Katherine M Cooper alessandro Colletta Nicholas Hebda Deepika Devuni Department of Medicine UMass Chan Medical SchoolWorcesterMA 01655United States Division of Gastroenterology UMass Chan Medical SchoolWorcesterMA 01655United States

Bariatric surgery is a routinely performed procedure and is associated with a reduction in all-cause mortality in patients with obesity.However,bariatric sur-gery has also been linked to increased alcohol use with up to 30%of these patients developing alcohol use disorder(AUD).The mechanism of AUD after bariatric surgery is multifactorial and includes anatomic,metabolic,and neurohumoral changes associated with post-surgical anatomy.These patients are at increased risk of alcohol associated liver disease and,in some cases,require liver trans-plantation.In this article,we provide a scoping review of epidemiology,patho-physiology,and clinical outcomes of alcohol-related health conditions after bariatric surgery.

关键词： Obesity medicine Alcohol use disorder Roux-en-Y gastric bypass Vertical sleeve gastrectomy Liver transplant Simultaneous liver transplant and bariatric surgery

Economic Risk Assessment of Future Debris Flows by Machine Learning Method

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International Journal of Disaster Risk Science 2024年第1期15卷 149-164页

作者： Chenchen Qiu Lijun Su alessandro Pasuto Giulia Bossi Xueyu Geng School of Engineering University of WarwickCoventry CV47ALUK Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China Research Institute for Geo-Hydrological Protection(IRPI-CNR) National Research Council of ItalyPadova 35127Italy

A reliable economic risk map is critical for effective debris-flow mitigation.However,the uncertainties surrounding future scenarios in debris-flow frequency and magnitude restrict its application.To estimate the economic risks caused by future debris flows,a machine learning-based method was proposed to generate an economic risk map by multiplying a debris-flow hazard map and an economic vulnerability map.We selected the Gyirong Zangbo Basin as the study area because frequent severe debris flows impact the area every year.The debris-flow hazard map was developed through the multiplication of the annual probability of spatial impact,temporal probability,and annual susceptibility.We employed a hybrid machine learning model-certainty factor-genetic algorithm-support vector classification-to calculate susceptibilities.Simultaneously,a Poisson model was applied for temporal probabilities,while the determination of annual probability of spatial impact relied on statistical results.Additionally,four major elements at risk were selected for the generation of an economic loss map:roads,vegetation-covered land,residential buildings,and farmland.The economic loss of elements at risk was calculated based on physical vulnerabilities and their economic values.Therefore,we proposed a physical vulnerability matrix for residential buildings,factoring in impact pressure on buildings and their horizontal distance and vertical distance to debrisflow channels.In this context,an ensemble model(XGBoost) was used to predict debris-flow volumes to calculate impact pressures on buildings.The results show that residential buildings occupy 76.7% of the total economic risk,while roadcovered areas contribute approximately 6.85%.Vegetation-covered land and farmland collectively represent 16.45% of the entire risk.These findings can provide a scientific support for the effective mitigation of future debris flows.

关键词： Economic risk Future debris fows Gyirong Zangbo Basin Machine learning model Physical vulnerability matrix Southwest Tibet,China

A Methodology for Vulnerability Assessment of Cultural Heritage in Extreme Climate Changes

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International Journal of Disaster Risk Science 2024年第3期15卷 404-420页

作者： Riccardo Cacciotti alessandro Sardella Milo? Drdácky Alessandra Bonazza Institute of Theoretical and Applied Mechanics Czech Academy of Sciences Institute of Atmospheric Sciences and Climate National Research Council of Italy Department of Environmental and Prevention Sciences University of Ferrara Istituto Superiore per la Protezione e la Ricerca Ambientale

Vulnerability evaluation plays a key role in risk assessment and reduction and is essential for defining strategies for climate change adaptation and mitigation. In dealing with the safeguarding of cultural heritage at risk, we are still far from adopting and applying an agreed methodology for vulnerability assessment. With the aim to support practitioners, heritage managers,and policy and decision makers to undertake actions that address the protection of cultural heritage at risk, the methodology set up in the framework of the Interreg Central Europe STRENCH is illustrated and discussed here. Based on three major requirements(susceptibility, exposure, and resilience) and a continuous consultation with local stakeholders, the proposed methodology is applicable for evaluating the vulnerability of built heritage and cultural landscape exposed to hydrometeorological hazards, such as heavy rains, floods, and droughts. The results obtained through its validation on 15 case studies from seven Central European regions are shown to underline the strengths and limitations of the methodological approach.Iterative consultation with local stakeholders was fundamental for the definition of the criteria/subcriteria and related values for the assessment of the requirements. Application to further sites in other contexts would surely contribute to strengthening the reliability of the methodological approach.

关键词： Built and natural heritage Exposure Heritage vulnerability Resilience Risk management Susceptibility