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Post-ablation surveillance in Barrett's esophagus: A review of the literature

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world Journal of Gastroenterology 2016年第17期22卷 4297-4306页

作者： Matthew w Stier Vani J Konda john Hart Irving waxman Department of Internal Medicine The University of Chicago Medicine Division of Gastroenterology Department of Medicine The University of Chicago Medicine Department of Pathology The University of Chicago Medicine

Barrett’s esophagus (BE) is a pre-malignant condition affecting up to 15% of patients with gastroesophageal reflux disease. Neoplastic Barrett’s mucosa is defined as harboring high grade dysplasia or intra-mucosal cancer, and carries a high risk of progression to esophageal adenocarcinoma. The rising incidence of Barrett’s lesions along with the high morbidity of surgical approaches has led to the development of numerous validated endoscopic techniques capable of eradicating neoplastic mucosa in a minimally invasive manner. while there has been widespread adoption of these techniques, less is known about optimal surveillance intervals in the post-therapy period. This is due in part to limitations in current surveillance methods, questions about durability of treatment response and the risk of subendothelial progression. As we are now able to achieve organ sparing eradication of superficial neoplasia in BE, we need to also then focus our attention on how best to manage these patients after eradication is achieved. Implementing optimal surveillance practices requires additional understanding of the biology of the disease, appreciation of the limits of current tools and treatments, and exploration of the role of adjunctive technologies. The aim of this article is to provide a comprehensive review of current literature surrounding post-ablation surveillance in neoplastic BE.

关键词： Barrett’ s esophagus Endotherapy Post-ablation surveillance Neoplastic Radiofrequency ablation Endoscopic mucosal resection

Effect of Cooling Rate on the Room Temperature Microstructure Following the Intercritical Deformation of Steel S460

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Journal of Iron and Steel Research International 2011年第S1期18卷 500-505页

作者： Hinton john S Palmiere Eric J Rainforth w.Mark IMMPETUS Dept.Of Materials Science and EngineeringThe University of SheffieldMappin StSheffieldSouth YorkshireS1 3JDUK

The effect of final hot rolling in the intercritical (α+γ) region on microstructure and properties is very specific to the individual processing conditions and the chemical composition of a steel.S460 is a plate steel processed in this *** reproduce at the laboratory scale,a multi-stage simulation was developed which included a high temperature austenite deformation and an isothermal *** effect of the applied cooling rate following intercritical deformation was *** 1K/s (typical industrial cooling) the microstructure was similar to the reference sample,but included an intragranular ferrite *** was due to differences in processing history,and considered to be linked to a larger prior austenite grain *** an accelerated cooling rate (15K/s),acicular ferrite formed on shear bands within the strained austenite *** scans have been completed to provide further information about the microstructures,with band contrast able to identify the pearlite phase at the slowest cooling *** is a starting point from which to focus on the ferrite morphologies.

关键词： intercritical deformation cooling rate laboratory simulation plate steel acicular ferrite

Development and clinical trial of a novel bioactive bone cement

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Frontiers of Medicine 2008年第2期2卷 117-126页

作者： john CY LEONG Zhaoyang LI william w LU The Open University of Hong Kong Hong Kong SAR.China Department of Orthopaedics and Traumatology The University of Hong KongHong Kong SAR.China

Strontium(Sr)and related compounds have become more attractive in the prevention and treatment of ***,we developed a novel bioactive bone cement which is mainly composed of strontium-con-taining hydroxyapatite(Sr-HA)filler and bisphenol A diglycidylether dimethacrylate(Bis-GMA)*** bone cement is superior to conventional polymethylmethacrylate(PMMA)bone cement in bioactivity,biocompatibility,and *** also has shown sufficient mechanical strength properties for its use in percutaneous vertebro-plasty(PVP)and total hip replacement(THR).In this paper,we review the in vitro,in vivo and clinical evidence for the effectiveness of this bioactive bone cement.

关键词： Strontium osteoporosis bioactive bone cement vertebroplasty total hip replacement

Prediction of DOM removal of low specific UV absorbance surface waters using HPSEC combined with peak fitting

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Journal of Environmental sciences 2012年第7期24卷 1174-1180页

作者： Linan Xing Rolando Fabris w.K.Chow john van Leeuwen Mary Drikas Dongsheng wang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of ScinecesBeijing 100085China Australian water Quality Centre South Australian Water Corporation256 Victoria SquareAdelaideSouth Australia 5000Australia SA water Centre for water Management and Reuse University of South AustraliaMawson LakesSouth Australia 5095Australia

High performance size exclusion chromatography （HPSEC） is used in water quality research primarily to determine the molecular weight distribution of the dissolved organic matter （DOM）, but by applying peak fitting to the chromatogram, this technique can also be used as a tool to model and predict DOM removal. Six low specific UV absorbance （SUVA） source waters were treated using coagulation with alum and both the source and treated water samples were analysed using HPSEC. By comparing the molecular weight profiles of the source and treated waters, it was established that several DOM components were not effectively removed by alum coagulation even after high dosage alum treatment. A peak-fitting technique was applied based on the concept of linking the character （molecular weight profile） of the recalcitrant organics in the treated water with those of the source water. This was then applied to predict DOM treatability by determining the areas of the peaks which were assigned to removable organics from the source water molecular weight profile after peak fitting, and this technique quantified the removable and non-removable organics. The prediction was compared with the actual dissolved organic carbon （DOC） removal determined from jar testing and showed good agreement, with variance between 2% and 10%. This confirmed that this prediction approach, which was originally developed for high SUVA waters, can also be applied successfully to predict DOC removal in low SUVA waters.

关键词： DOM high performance size exclusion chromatography peak fitting water treatment

Using Doubly-Labeled water to Measure Energy Expenditure in an Important Small Ectotherm Drosophila melanogaster

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Journal of Genetics and Genomics 2014年第9期41卷 505-512页

作者： Matthew D.w.Piper Colin Selman john R.Speakman Linda Partridge Institute of Healthy Ageing Department of GeneticsEvolution and EnvironmentUniversity College LondonGower StreetLondonWCIE 6BTUK Institute of Biodiversity Animal Health and Comparative Medicine University of Glasgow Institute of Biological and Environmental sciences University of Aberdeen State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of Sciences

Energy expenditure is a key variable in the study of ageing, and the fruit fly Drosophila melanogaster is a model organism that has been used to make step changes in our understanding of the ageing process. Standard methods for measurement of energy expenditure involve placing individuals in metabolic chambers where their oxygen consumption and CO2 production can be quantified. These measurements require separating individuals from any social context, and may only poorly reflect the environment in which the animals normally live. The doubly-labeled water （DLw） method is an isotope-based technique for measuring energy expenditure which overcomes these problems. However, technical challenges mean that the smallest animals this method has been previously applied to weighed 50-200 mg. we overcame these technical challenges to measure energy demands in Drosophila weighing 0.78 mg. Mass-specific energy expenditure varied between 43 and 65 mw·g^-1. These estimates are considerably higher than estimates using indirect calorimetry of Drosophila in small metabolic chambers （around 18 mw·g^-1）. The methodology we have established extends downwards by three orders of magnitude the size of animals that can be measured using DLw. This approach may be of considerable value in future ageing research attempting to understand the genetic and genomic basis of ageing.

关键词： Doubly-labeled water Respiration rate Effect of mating status and sex Drosophila

Cortical and spinal evoked potential response to electrical stimulation in human rectum

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world Journal of Gastroenterology 2010年第43期16卷 5440-5446页

作者： Brian Garvin Lisa Lovely Alex Tsodikov Danielle Minecan Shaungson Hong john w wiley Department of Internal Medicine University of Michigan Michigan Clinical Research Unit Level 1 Room 1702 Cardiovascular Center 1500E Medical Center Drive Ann Arbor MI 48109 United States Department of Neurology University of Michigan Ann Arbor MI 48109 United States Department of Biostatistics University of Michigan Ann Arbor MI 48109 United States

AIM: To study a novel technique to record spinal and cortical evoked potentials (EPs) simultaneously in response to electrical stimulation in the human rectum. METHODS: Eight male and nine female healthy volunteers participated. Stimulating electrodes were attached to the rectal mucosa at 15 cm and 12 cm above the dentate line. Recording skin electrodes were positioned over vertebrae L4 through S2. The electrical stimulus was a square wave of 0.2 ms duration and the intensity of the stimulus varied between 0 and 100 mA. EP responses were recorded using a Nicolet Viking IV programmable signal ***: Simultaneous recording of cortical and spinal EPs was obtained in > 80% of the trials. The EP responses increased with the intensity of the electrical stimulation, were reproducible overtime, and were blocked by application of Lidocaine jelly at the site of stimulation. The morphology (N1/P1), mean ± SD for latency (spinal N1, 4.6 ± 0.4 ms; P1, 6.8 ± 0.5 ms; cortical N1, 136.1 ± 4.2 ms; P1, 233.6 ± 12.8 ms) and amplitude (N1/P1, spinal, 38 ± 7 μV; cortical 19 ± 3 μV) data for the EP responses were consistent with those in the published literature. Reliable and reproducible EP recordings were obtained with the attachment of the electrodes to the rectal mucosa at predetermined locations between 16 and 8 cm above the anal verge, and the distance between the attachment sites of the electrodes (the optimal distance being approximately 3.0 cm between the two electrodes). CONCLUSION: This technique can be used to assess potential abnormalities in primary afferent neural pathways innervating the rectum in several neurodegenerative and functional pain disorders.

关键词： Spinal evoked potentials Cortical evoked potentials Rectum Electrical stimulation Primary afferent neurons Visceral sensation

Linewidth narrowing in self-injection-locked on-chip lasers

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Light(science & Applications) 2023年第10期12卷 2074-2083页

作者： Emad Alkhazraji weng w.Chow Frédéric Grillot john E.Bowers Yating wan Integrated Photonics Lab King Abdullah University of Science and TechnologyThuwal 23955Saudi Arabia Sandia National Laboratories AlbuquerqueNM 87185-1086USA LTCI Télécom ParisInstitut Polytechnique de Paris91120 PalaiseauFrance Department of Electronic and Computer Engineering University of California-Santa BarbaraSanta BarbaraCA 93106USA

Stable laser emission with narrow linewidth is of critical importance in many applications,including coherent communications,LIDAR,and remote *** this work,the physics underlying spectral narrowing of self-injection-locked on-chip lasers to Hz-level lasing linewidth is investigated using a composite-cavity *** integrated III–V/SiN lasers operating with quantum-dot and quantum-well active regions are analyzed with a focus on the effects of carrier quantum *** intrinsic differences are associated with gain saturation and carrier-induced refractive index,which are directly connected with 0-and 2-dimensional carrier densities of *** from parametric studies are presented for tradeoffs involved with tailoring the linewidth,output power,and injection current for different device *** both quantum-well and quantum-dot devices show similar linewidth-narrowing capabilities,the former emits at a higher optical power in the self-injection-locked state,while the latter is more ***,a multi-objective optimization analysis is provided to optimize the operation and design *** the quantum-well laser,minimizing the number of quantum-well layers is found to decrease the threshold current without significantly reducing the output *** the quantum-dot laser,increasing the quantum-dot layers or density in each layer increases the output power without significantly increasing the threshold *** findings serve to guide more detailed parametric studies to produce timely results for engineering design.

关键词： narrowing injection quantum

Clinical implications of the molecular characterization of intraductal papillary mucinous neoplasms of the pancreas

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Journal of Cancer Metastasis and Treatment 2021年第1期7卷 430-447页

作者： Nicholas V.Peters john w.Kunstman Department of Surgery Yale University School of MedicineNew Haven 06510CTUSA.

Intraductal papillary mucinous neoplasm(IPMN)is a pre-malignant,mucin-producing epithelial lesion arising from pancreatic *** reports define IPMN behavior as ranging from indolent,asymptomatic lesions to dysplasia that sometimes degenerate into pancreatic *** goal of IPMN management is risk-reducing surgery for high-risk cysts and observation of the *** high-from low-risk IPMN disease still relies on imaging and clinical cyst ***,we review the accepted classification of IPMN including the most common histological subtypes,their clinical features,and currently-accepted high-risk *** then deeply examine the known molecular landscape of IPMN,which has largely been derived from post-resection *** includes those gene variants unique to IPMN,chiefly GNAS and RNF43,but also examines the overlap between IPMN and conventional pancreatic *** molecular markers in the clinical setting relies on endoscopically-obtained cyst fluid and presumes that it accurately represents the molecular characteristics of the cystic *** synthesize existing data on mutational analysis from IPMN cyst fluid and consider the benefits and proper role of current commercially-available cyst fluid molecular analysis *** conclude that carefully interpreted molecular analysis of resected IPMN tissue reveals insights into its biology and natural history while cyst fluid analysis offers prognostication and data to guide treatment ***,knowledge gaps remain,especially in characterizing IPMN molecular heterogeneity,time to progression,and correlating cyst fluid genotype data with surveillance *** such,substantial additional research is required before the promise of true molecular guidance of IPMN management can be realized.

关键词： Intraductal papillary mucinous neoplasm pancreatic cancer molecular analysis GNAS KRAS RNF43

Classifying forest inventory data into species-based forest community types at broad extents： exploring tradeoffs among supervised and unsupervised approaches

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Forest Ecosystems 2018年第1期5卷 91-107页

作者： jennifer k.costanza don faber-langendoen john w.coulston david n.wear Department of Forestry and Environmental Resources North C arolina State University3041 Cornwalis RdResearch Triangle ParkRaleighNC 27709USA NatureServe 4600 N.Fairfax Dr7th FloorArlingtonVA 22203USA Southern Research Station USDA Forest ServiceBlacksburgVAUSA Southern Research Station USDA Forest ServiceRaleighNCUSA

Background： Knowledge of the different kinds of tree communities that currently exist can provide a baseline for assessing the ecological attributes of forests and monitoring future changes. Forest inventory data can facilitate the development of this baseline knowledge across broad extents, but they first must be classified into forest community types. Here, we compared three alternative classifications across the United States using data from over 117,000 U.S. Department of Agriculture Forest Service Forest Inventory and Analysis （FIA） plots. Methods： Each plot had three forest community type labels：（1）＂FIA＂ types were assigned by the FIA program using a supervised method; （2）＂USNVC＂ types were assigned via a key based on the U.S. National Vegetation Classification; （3）＂empirical＂ types resulted from unsupervised clustering of tree species information. we assessed the degree to which analog classes occurred among classifications, compared indicator species values, and used random forest models to determine how well the classifications could be predicted using environmental variables. Results： The classifications generated groups of classes that had broadly similar distributions, but often there was no one-to-one analog across the classifications. The Iongleaf pine forest community type stood out as the exception： it was the only class with strong analogs across all classifications. Analogs were most lacking for forest community types with species that occurred across a range of geographic and environmental conditions, such as Ioblolly pine types, indicator species metrics were generally high for the USNVC, suggesting that LJSNVC classes are floristically well-defined. The empirical classification was best predicted by environmental variables. The most important predictors differed slightly but were broadly similar across all classifications, and included slope, amount of forest in the surrounding landscape, average minimum temperature, and other climate variab

关键词： Big data Correspondence analysis Dominant species Forest communities Global change,Hierarchical classification Indicator species Random forests Species assemblages