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Exploring emerald global geochemical provenance through fingerprinting and machine learning methods

Artificial Intelligence in Geosciences 2024年第1期5卷 202-219页

作者： Raquel Alonso-Perez james M.d.day d.Graham Pearson Yan Luo Manuel A.Palacios Raju Sudhakar Aaron Palke Earth and Planetary Science department Harvard UniversityCambridgeMA02138USA Scripps Institution of Oceanography University of California San DiegoLa JollaCA92037USA University of Alberta EdmontonABT6G 2R3Canada Eigenvector Research Inc.Manson WA98831USA Rockhurst University Kansas CityMO64110USA Gemological Institute of America CarlsbadCA92008USA

Emeralds-the green colored variety of beryl-occur as gem-quality specimens in over fifty deposits *** digital traceability methods for emerald have limitations,sample-based approaches offer robust alterna-tives,particularly for determining the geographic origin of *** factors make emerald suitable for provenance studies and hence for developing models for origin ***,the diverse elemental chemistry of emerald at minor(d trace levels(destructive techniques,including laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS),enable measurement of these diagnostic elemental ***,when applied to extensive datasets,machine learning(ML)techniques enable the creation of predictive models and statistical discrimination with adequate characterization of the *** study em-ploys a carefully selected dataset comprising more than 1000 LA-ICP-MS analyses of gem-quality emeralds,enriched with new *** dataset represents the largest available for global emerald *** con-ducted unsupervised exploratory analysis using Principal Component Analysis(PCA).For machine learning-based classification,we employed Support Vector Machine Classification(SVM-C),achieving an initial accu-racy rate of 79%.This was enhanced to 96.8%through the use of hierarchical SVM-C with PCA filters as our modeling *** ML models were trained using the concentrations of eight statistically significant ele-ments(Li,V,Cr,Fe,Sc,Ga,Rb,Cs).By leveraging high-quality LA-ICP-MS data and ML techniques,accurate identification of the geographical origin of emerald becomes *** models are important for accurate provenance of emerald,and from a geochemical perspective,for understanding the formation environments of beryl-bearing pegmatites and shales.

关键词： Beryl Provenance LA-ICP-MS Machine learning Multivariate analysis Trace elements

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Late post liver transplant protein losing enteropathy: Rare complication of incisional hernia

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World Journal of Gastroenterology 2013年第27期19卷 4409-4412页

作者： Jonathan d Evans M Thamara PR Perera CY Pal james Neuberger darius F Mirza The Liver Unit The Queen Elizabeth Hospital

development of oedema and hypoproteinaemia in a liver transplant recipient may be the first signs of graft dysfunction and should prompt a full assessment. We report the novel case of a patient who, years after liver transplantation developed a functional blind loop in an incisional hernia, which manifested as oedema and hypoproteinaemia secondary to protein losing enteropathy. After numerous investigations, the diagnosis was made by flurodeoxyglucose positron emmision tomography (FdG-PET) imaging. Surgical repair of the incisional hernia was followed several months later by resolution of the protein loss, and confirmed at a post operative FdG-PET scan at one year.

关键词： Protein losing enteropathies Bacterial overgrowth Hypoproteinaemia Incarcerated hernia Liver transplantation.

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Large-diameter trees, snags, and deadwood in southern Utah, USA

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Ecological Processes 2021年第1期10卷 130-141页

作者： james A.Lutz Soren Struckman Tucker J.Furniss Joseph d.Birch Larissa *** darren J.McAvoy department of Wildland Resources S.J.and Jessie E.Quinney College of Natural ResourcesUtah State University5230 Old Main HillLoganUT 84322-5230USA. department of Renewable Resources University of AlbertaEdmontonAlbertaCanada.

Background:The epidemic dendroctonus rufipennis(spruce beetle)outbreak in the subalpine forests of the Colorado Plateau in the 1990s killed most larger Picea engelmannii(Engelmann spruce)*** quarter century later,the larger snags are beginning to fall,transitioning to deadwood(down woody debris)where they may influence fire behavior,regeneration,and habitat ***:We tracked all fallen trees≥1 cm in diameter at breast height(1.37-m high)and mapped all pieces of deadwood≥10-cm diameter and≥1 m in length within 13.64 ha of a high-elevation mixed-species forest in the Picea–Abies zone annually for 5 years from 2015 through *** examined the relative contribution of Picea engelmannii to snag and deadwood pools relative to other species and the relative contributions of large-diameter trees(≥33.2 cm at this subalpine site).We compared spatially explicit mapping of deadwood to traditional measures of surface fuels and introduce a new method for approximating vertical distribution of ***:In this mixed-species forest,there was relatively high density and basal area of live Picea engelmannii 20 years after the beetle outbreak(36 trees ha^(−1) and 1.94 m^(2) ha^(−1)≥10-cm diameter)contrasting with the near total mortality of mature Picea in forests *** from tree boles≥10-cm diameter on the ground had biomass of 42 Mg ha^(−1),7 Mg ha^(−1) of Picea engelmannii,and 35 Mg ha^(−1) of other *** live aboveground biomass was 119 Mg ha^(−1),while snag biomass was 36 Mg ha^(−1).Mean total fuel loading measured with planar transects was 63 Mg ha^(−1) but varied more than three orders of magnitude(0.1 to 257 Mg ha^(−1)).Planar transects recorded 32 Mg ha^(−1) of wood≥7.62-cm diameter compared to the 42 Mg ha^(−1) of wood≥10-cm diameter recorded by explicit *** pieces of deadwood were often stacked,forming a vertical structure likely to contribute to active fire ***:Bark beetle mortality in the 1990s has made

关键词： Cedar Breaks National Monument dendroctonus rufipennis Utah Forest dynamics Plot Vertical fuel structure

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Two-dimensional near-infrared photonic crystal fabrication by generation of void channels in solid resin

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Chinese Optics Letters 2003年第12期1卷 719-721页

作者： Michael james Ventura Centre for Micro-Phtonics and the Centre for Ultrahigh-Highwidth devices for Optical Systems School of Biophysical Sciences and Electrical Engineering Swinburne University of Technology PO Box 218 Hawthorn Victoria 3122 Australia

Two-dimensional (2d) triangular void channel photonic crystals with different lattice constants stacked in two different directions were fabricated by using femtosecond laser micro-explosion in solid polymer material. Fundamental and higher-order stop gaps were observed both in the infrared transmission and reflection spectra. There is an approximately linear relationship between the gap position and the lattice constant. The suppression of the fundamental gap is as high as 70% for 24-layer structures stacked in the T-M direction.

关键词： of as Two-dimensional near-infrared photonic crystal fabrication by generation of void channels in solid resin by that were for with

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Associations of lifestyle and diet with the risk of nasopharyngeal carcinoma in Singapore:a case–control study

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Chinese Journal of Cancer 2017年第2期36卷 63-70页

作者： Sook Kwin Yong Tam Cam Ha Ming Chert Richard Yeo Valerie Gaborieau james d.McKay Joseph Wee division of Clinical Trials and Epidemiological Sciences National Cancer Centre Singapore11 Hospital DriveSingapore 169610Singapore Medical Education Research&Evaluation Department(MERE)Duke-NUS Medical School8 College RoadSingapore 169857Singapore division of Radiation Oncology National Cancer Centre Singapore11 Hospital DriveSinga-pore 169610Singapore Genetic Cancer Susceptibility Group International Agency for Research on CancerWorld Health Organization150 Cours Albert Thomas69372 Lyon Cedex 08France

Background: Nasopharyngeal carcinoma(NPC) is a commonly diagnosed cancer in Southeast Asia. Many studies have examined the risk factors for NPC, yet the roles of some risk factors remain inconclusive. The purpose of this study was to examine associations between modifiable lifestyle factors and the risk of NPC in the Singaporean ***: We conducted a case–control study in Singapore with 300 patients and 310 controls who were recruited between 2008 and 2012. Each control was selected and individually matched to each patient based on sex, ethnicity, and age(±5 years). A total of 290 pairs of cases and controls were matched successfully. We examined lifestyle factors such as tobacco smoking, alcohol drinking, various salted and preserved food consumption, and weaning ***: After adjusting for covariates, multivariate analysis showed that those participants who were current smokers and had ever smoked tobacco had a higher risk of NPC than participants who had never smoked, with odds ratios(ORs) of 4.50(95% confidence interval [CI] 2.58–7.86; P d 2.52(95% CI 1.54–4.12; P d salted vegetables at least once a week also showed a significantly increased risk of NPC than those who never or rarely consumed salted vegetables, with an OR of 4.18(95% CI 1.69–10.38; P = 0.002).Conclusion: Smoking(currently and ever-smoked) and consuming salted vegetables once a week or more were lifestyle risk factors for NPC, and changes of these factors for the better may reduce the risk of NPC.

关键词： Nasopharyngeal carcinoma diet Smoking Alcohol drinking Case–control study Preserved food

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A spatiotemporal analysis of the impact of lockdown and coronavirus on London’s bicycle hire scheme:from response to recovery to a new normal

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Geo-Spatial Information Science 2023年第4期26卷 664-684页

作者： Xiaowei Gao Huanfa Chen james Haworth SpaceTimelab Department of CivilEnvironmental and Geomatic EngineeringUniversity College LondonLondonUnited Kingdom Centre for Advanced Spatial Analysis University College LondonLondonUnited Kingdom

The coronavirus pandemic that started in 2019 has had wide-ranging impacts on many aspects of people’s daily *** the peak of the outbreak,lockdown measures and social distancing changed the ways in which cities *** particular,they had profound impacts on urban transportation systems,with public transport being shut down in many *** share systems(BSS)were widely reported as having experienced an increase in demand during the early stages of the pandemic before returning to pre-pandemic ***,the studies published to date focus mainly on the first year of the pandemic,when various waves saw continual relaxing and reintroductions of ***,they fall short of exploring the role of BSS as we move to the post-pandemic *** address this gap,this study uses origin-destination(O-d)flow data from London’s Santander Cycle Hire Scheme from 2019-2021 to analyze the changing use of BSS throughout the first two years of the pandemic,from lockdown to recovery.A Gaussian mixture model(GMM)is used to cluster 2019 BSS trips into three distinct clusters based on their duration and *** clusters are used as a reference from which to measure spatial and temporal change in 2020 and *** agreement with previous research,BSS usage was found to have declined by nearly 30%during the first *** then saw a sharp increase as restrictions were lifted,characterized by longer,less direct trips throughout the afternoon rather than typical peak commuting *** the aggregate number of BSS trips appeared to return to normal by October 2020,this was against the backdrop of continuing restrictions on international travel and work from home *** period between July and december 2021 was the first period that all government restrictions were *** this time,BSS trips reached higher levels than in ***-temporal analysis indicates a shift away from the traditional morning and evening peak to a more diffuse p

关键词： COVId-19 micro-mobility restrictive measures bicycle share system

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development and application of molecular gut-content analysis to detect aphid and coccinellid predation by Harmonia axyridis （Coleoptera： Coccinellidae）in Italy

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Insect Science 2015年第6期22卷 719-730页

作者： Gabriele Rondoni Kacie J. Athey james d. Harwood Eric Contit Carlo Ricci John J. Obrycki department of Agricultural Food and Environmental Sciences University of Perugia Borgo XX Giugno 74 Perugia 06121 Italy and department of Entomology University of Kentucky S-225 Agricultural Science Center North Lexington KY 40546-0091 USA

despite their positive effect in reducing pest populations, exotic generalist predators sometimes become invasive and contribute to the displacement of indigenous species in the same trophic level. Although laboratory experiments have linked intraguild predation （IGP） to these interactions, field evidence and quantification of IGP are still lacking for most systems. The recent establishment of the exotic Harmonia axyridis （Pallas）（Coleoptera： Coccinellidae） in Italy raises concern about the detrimental effect that the ladybird could have on native coccinellids. Here we assessed, under laboratory conditions, the acceptability and suitability of eggs of 2 native ladybirds, Adalia bipunctata L. and Oenopia conglobata （L.）, as prey items for H. axyridis larvae. Then we developed primers for molecular gut-content analysis to detect predation by H. axyridis on the 2 ladybirds and on the aphid Eucallipterus tiliae L. Species-specific 16S primers were developed for the 3 species and laboratory feeding trials were conducted to quantify the rate of prey dNA breakdown in the gut of//. axyridis. Moreover, to field evaluate primers, H. axyridis 4th instars （n = 132） were systematically collected from linden trees in northern Italy and screened for the presence of prey dNA. Seventy-three percent and 7% of field collected H. axyridis were positive for aphid and coccinellid dNA, respectively. Predation upon aphid and A. bipunctata was lower than predicted if density dependent consumption was expected, while predation upon O. conglobata was significantly higher. Here, we provided the first evidence of IGP among feral populations ofH. axyridis and indigenous ladybird beetles, occurring in Italy.

关键词： Adalia bipunctata biological control Eucallipterus tiliae intraguild inter-actions nontarget effect Oenopia conglobata

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Peripartum cardiomyopathy: A puzzle closer to solution

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World Journal of Cardiology 2014年第3期6卷 87-99页

作者： james d Fett Investigations of Pregnancy Associated Cardiomyopathy (IPAC) Peripartum Cardiomyopathy Network of North America (PCN)Cardiovascular InstituteUniversity of Pittsburgh Medical Center department of Adult Medicine Hospital Albert Schweitzer

Peripartum cardiomyopathy(PPCM) represents new heart failure in a previously heart-healthy peripartum patient. It is necessary to rule out all other known causes of heart failure before accepting a diagnosis of PPCM. The modern era for PPCM in the United States and beyond began with the report of the National In-stitutes of Health PPCM Workshop in 2000, clarifying all then-currently known aspects of the disease. Since then, hundreds of publications have appeared, an indi-cation of how devastating this disease can be to young mothers and their families and the urgent desire to find solutions for its cause and better treatment. The purpose of this review is to highlight the important ad-vances that have brought us nearer to the solution of this puzzle, focusing on what we have learned about PPCM since 2000; and what still remains unanswered. despite many improvements in outcome, we still do not know the actual triggers that initiate the pathological process; but realize that cardiac angiogenic imbalances resulting from complex pregnancy-related immune sys-tem and hormonal changes play a key role.

关键词： Peripartum cardiomyopathy Pregnancy Heart failure

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THE　RISE　ANd　dECLINE　OF　THE　UNITEd　STATES　SHIPPING　ANd　SHIPBUILdING　INdUSTRIES

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上海交通大学学报 1994年第6期 1-10页

作者： (Captain james S.C.Chao,dCS,LL.d.John J.Clark,Ph.d.)

ＴＨＥＲＩＳＥＡＮＤＤＥＣＬＩＮＥＯＦＴＨＥＵＮＩＴＥＤＳＴＡＴＥＳＳＨＩＰＰＩＮＧＡＮＤＳＨＩＰＢＵＩＬＤＩＮＧＩＮＤＵＳＴＲＩＥＳ￥（ＣａｐｔａｉｎＪａｍｅｓＳ．Ｃ．Ｃｈａｏ，ＤＣＳ，ＬＬ．Ｄ．ＪｏｈｎＪ．Ｃｌａ... 详细信息

ＴＨＥＲＩＳＥＡＮＤＤＥＣＬＩＮＥＯＦＴＨＥＵＮＩＴＥＤＳＴＡＴＥＳＳＨＩＰＰＩＮＧＡＮＤＳＨＩＰＢＵＩＬＤＩＮＧＩＮＤＵＳＴＲＩＥＳ￥（ＣａｐｔａｉｎＪａｍｅｓＳ．Ｃ．Ｃｈａｏ，ＤＣＳ，ＬＬ．Ｄ．ＪｏｈｎＪ．Ｃｌａｒｋ，Ｐｈ．Ｄ．）Ａｂｓｔｒａｃｔ...

关键词： shipping industry shipbuilding industry management

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delayed reception of live blowfly (Calliphora vicina and Chrysomya rufifacies)larval samples: implications for minimum postmortem interval estimates

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Forensic Sciences Research 2018年第1期3卷 27-39页

作者： Melanie S.Archer Stephanie d.Jones james F.Wallman department of Forensic Medicine Monash University/Victorian Institute of Forensic MedicineSouthbankAustralia Centre for Sustainable Ecosystem Solutions School of Biological SciencesUniversity of WollongongWollongongAustralia

Forensic entomology evidence collected by police and mortuary staff may be delayed in getting to the *** samples may continue developing and alter minimum postmortem interval (PMImin) *** study investigated development of simulated evidential samples of Calliphora vicina Robineau-desvoidy and Chrysomya rufifacies (Macquart) (diptera: Calliphoridae) *** of each species were studied in three developmental classes: "small" (late second/early third instar),"mid" (mid third instar) and "large" (late third instar).Seven replicates of 11 maggots in each class were assigned without food to four treatments: (1) 24 h at 20 ℃;(2) 24 h at 4 ℃;(3) 48 h at 20 ℃ and (4) 48 h at 4 ℃.There was a significant difference in absolute length change across treatments,reflecting size for C vicina,and interaction between size,time and temperature for *** vicina maggots showed minimal mortality,and most second instar larvae moulted by the experiment's *** rufifacies showed heavy mortality and minimal moulting from the second to third *** "large" *** maggots kept at room temperature for 48 h *** these results confirm that development can continue in live unfed maggot samples after their collection,it is not advisable to delay their preservation.

关键词： Forensic science forensic entomology forensic evidence larval development best practice sampling

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