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RADICAL GRAFTING REACTIONS ONTO STARCH AND OTHER WATER-SOLUBLE COpOLYMERS IN ISOLATED GEL DROpLETS

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Chinese Journal of polymer Science 1993年第2期11卷 144-152页

作者：张连生 A.F.johnson Department of Chemistry and Chemical Technology University of Bradford Bradford BD7 IDP England Dpt.Chem.Heilongjiang Universiry24 Xuefu Road Harbin 150080 China Received December 231991. Department of Chemistry and Chemical Technology University of Bradford Bradford BD7 IDP England

A novel radical grafting copolymerization process has been designed for water-soluble polymers which avoids the problems of conducting grafting reactions in highly viscous polymerization media. A variety of water-soluble graft copolymers having starch or dextran as the backbone chain with grafted side chains of polyacrylamide (—AM—), poly (acrylic acid ) (—AA—), poly (acrylamide-co-acrylic acid) (—AM—NH_4AA—) or poly ( acrylamide-co-2-acryiamido-2-methyl-l-propanesulphinic acid) (—AM—AMpS—) have been synthesized in gel droplets using aceric sulphate redox initiator, and their properties compared. The reaction conditions were optimized taking into account reaction kinetic data and the observed properties of the products produced under different reaction conditions. The effects of the ratios of [backbone]/[graft monomer], [ AM]/[ AA]/[AMpS] , [Ce^(4+)]/[ S_2O_8=] and pH value on the reaction rate , conversion, grafting degree, grafted chain length and the product molecular weight have been investigated.

关键词： Radical grafting copolymerization Isolated gel droplets, Acrylamide Starch Kinetics

Convergence of the turkey gut microbiota following cohabitation under commercial settings

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Journal of Animal Science and Biotechnology 2021年第4期12卷 1635-1644页

作者： Elizabeth A.Miller Brittanie Winfield Bonnie p.Weber Cristian Flores-Figueroa Jeannette Munoz-Aguayo Jared Huisinga Timothy J.johnson Department of Veterinary and Biomedical Sciences University of MinnesotaSaint PaulMNUSA University of Minnesota Mid-Central Research and Outreach CenterWillmarMNUSA Science Innovations WillmarMNUSA

Background:Microbiota development is a critical aspect of turkey poult maturation,and the succession of microbes in the turkey gut has been shown to correlate with poult *** purpose of this study was to determine the fate of the microbiota in turkey poults after movement of birds first raised in an isolated hatch brood system into a more traditional commercial brood facility with pre-existing *** poults were first divided into groups raised in conventional brood pens from day-of-hatch and those raised in an experimental hatch brood *** 11 days of growth,hatch brood birds were moved into pens within the conventional brood barn and monitored for an additional 18 *** of both hatch brood and conventional pen birds was performed at multiple timepoints throughout the study,and cecal content was used to analyze the bacterial microbiota using 16S rRNA gene amplicon ***:Alpha diversity tended to be higher in samples from conventional pen birds compared to those from hatch brood birds prior to the day 11 move,but the difference between systems was not observed *** beta diversity metrics,bacterial community succession appeared delayed in the hatch brood system birds pre-move,but post-move community composition quickly converged with that of the conventional pen *** was validated through assessment of significantly different genera between hatch brood system and conventional pen birds,where numbers of significantly different taxa quickly decreased following the *** key taxa previously associated with poult performance were delayed in their appearance and relative abundance in hatch brood ***:Overall,this study demonstrates that the use of isolated hatch brood systems has an impact on the poult gut microbiota,but its impact is resolved quickly once the birds are introduced into a conventional brood ***,the benefits of pathogen reduction with hatch brood systems may out

关键词： Brood Gut Hatch Microbiota poult Succession Turkey

Void fill and support techniques to stabilize drift excavated through a transition zone mined by a TBM at the Stillwater mine

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International Journal of Mining Science and Technology 2017年第1期27卷 71-76页

作者： johnson Josh Jacobs Curt Ferster Mark Tadolini Stephen Stillwater Mining Company NyeMT 59061USA Minova GeorgetownKYUSA

Stillwater Mining Company is the only U.S. producer of platinum group metals （pGMs） and the largest producer outside of South Afiica and Russia. The company controls a considerable portion of the J-M reef and is currently developing the ＂Blitz project,＂ which will provide a main haulage level, ore pass systems, backfill plants, and fiow-through ventilation to increase production and ensure sustainable extraction of this critical strategic mineral. While driving two sub-parallel footwall laterals 8125 m in length, one of the development drifts experienced a massive fall in a geologically disturbed area created by a mafic dike intrusion. Combinations of a void fill material （Tekseal）, polyurethane injection, fore poling coupled with steel arches, and supplemental bolting allow safe and efficient advance through this geologically dis- turbed zone. This paper presents the details of this project.

关键词： TBM Ground Dike Cutterhead

Evaluation of the 20 L dust explosibility testing chamber and comparison to a modified 38 L vessel for underground coal

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International Journal of Mining Science and Technology 2018年第6期28卷 885-890页

作者： Robert Eades Kyle perry Catherine johnson Jacob Miller Department of Mining and Nuclear Engineering Missouri University of Science and Technology

The phenomenon of combustible dust explosions is present within many industries. Tests for explosibility of dust clouds per ASTM E1226 use a 20 L explosive chamber that places the combustible dust directly below the dispersion nozzle which generates a thorough mixture for testing purposes. However, in the underground coal mining industry, there are a number of geologic, mining, and regulatory factors that change the deposition scheme of combustible coal dust. This causes the atmosphere of a coal mine to have a variable rock dust-coal dust mixture at the time of ignition. To investigate the impact of this variable atmosphere, a series of lean explosibility tests were conducted on a sample of pittsburgh pulverized coal dust. These explosibility tests were conducted in a 38 L chamber with a 5 kJ Sobbe igniter. The 38 L chamber generates a variable air-dust mixture prior to ignition. The test results indicate that the 38 L chamber experiences reduced explosive pressures, and lower explosibility index values when compared to the 20 L chamber.

关键词： Dust explosion Coal mining Coal dust Explosibility testing

A new approach for deposition of silver film from AgCl through successive ionic layer adsorption and reaction technique

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Journal of Central South University 2017年第12期24卷 2793-2798页

作者： johnson Henry Arockiasamy Ajaypraveenkumar Ganesan Sivakumar Kannusamy Mohanraj Department of physics Manonmaniam Sundaranar University Tirunelveli-627 012 Tamil Nadu India CISL Department of Physics Annamalai University Annamalai nagar-608 002 Tamil Nadu India

An attempt was made to deposit thin film of silver onto the glass substrate by using Ag Cl precursor, instead of conventional precursor AgNO_3 with vitamin C by inexpensive and convenient successive ionic layer adsorption and reaction(SILAR) method. The deposited silver thin film was characterized by X-ray diffraction(XRD) analysis, scanning electron microscope(SEM), UV-visible and electrical I-V study. The diffraction study showed FCC structure of metallic silver in good agreement with the standard values of JCpDS(04–0783). SEM reveals flower like nano particles produced on the substrate. The surface plasmon resonance(SpR) peak in the UV-visible spectrum shows maximum absorption at 350 nm. The film shows an ohmic behavior and its electrical resistivity was found ~103 ?·cm at room temperature.

关键词： thin films metals materials characterization sol-gel optical properties silver

Growth characteristics of algae during early stages of phytoplankton bloom in Lake Taihu,China

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Journal of Environmental Sciences 2013年第2期25卷 254-261页

作者： Yuhong Jia johnson Dan Min Zhang Fanxiang Kong State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of Sciences Graduate School of Chinese Academy of Sciences Water and Environmental Science Building Department of GeographyUniversity of LethbridgeLethbridgeAlbertaT1K 3M4Canada

Three treatments, sediment plus lake water （S＋W）, sterilized sediment plus lake water （SS＋W）, and sediment plus filtered lake water （S＋FW）, were recruited to investigate the growth characteristics of algae during pre-bloom and the importance of algal inocula in the water column and sediment. The results showed that in the water column, biomass of all algae increased in all treatments when recruitment was initiated, whereas this tendency differed among treatments with further increment of temperature. The process of algal growth consisted of two stages： Stage I, the onset of recruitment and Stage II, the subsequent growth of algae. Compared with S＋W, in Stage I, SS＋W significantly increased the biomass of cyanophytes by 178.70%, and decreased the biomass of non-cyanophytes by 43.40%; In Stage II, SS＋W notably stimulated the growth of all algae, thus incurring the occurrence of phytoplankton bloom. Further analyses revealed that both metabolic activity and photochemical activity of algae were enhanced in SS＋W, which resulted from the releasing of nutrients from sediment. These results suggest that algal growth in Stage II and algal inocula in the water column can be important factors for the formation of phytoplankton bloom. In addition, possible mechanisms promoting algal recruitment and subsequent growth of algae were explored.

关键词： algae recruitment phytoplankton bloom water column sediment

CDX2 protein expression compared to alcian blue staining in the evaluation of esophageal intestinal metaplasia

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World Journal of Gastroenterology 2015年第9期21卷 2770-2776页

作者： Dennis R johnson Maisoun Abdelbaqui Maryam Tahmasbi Zoltan Mayer Hung-Wei Lee Mokenge p Malafa Domenico Coppola Department of Anatomic pathology Moffitt Cancer Center and Research InstituteTampaFL 33612United States Florida Digestive Health Specialists Lakewood RanchFL 34202United States Department of Oncological Sciences University of South FloridaTampaFL 33612United States GI Tumor program Moffitt Cancer Center and Research InstituteTampaFL 33612United States Tumor Biology program Moffitt Cancer Center and Research InstituteTampaFL 33612United States

AIM:To compare the sensitivity and specificity of CDX2 and alcian blue(AB) p H 2.5 staining in identifying esophageal intestinal ***:One hundred and ninty-nine biopsies from 186 patients were retrospectively reviewed and categorized as Barrett's esophagus(BE)(n =108); non-Barrett's esophagus(NBE)(n =48); columnar blue cells(CB) and esophageal glands(EG)(n =43).The biopsies were stained with AB and immunostained for CDX2 using a mouse monoclonal antibody from Biogenex(clone CDX2-88) and the Ventana Discovery X automated *** positive and negative predictive value of each group was used to determine the predictive power of CDX2 and AB in diagnosing intestinal ***:All of the 108 BE biopsies(100%) were positive for AB and 102 of them(94.4%) were positive for *** six BE patients(5.6%) who failed to stain with CDX2 were found to have lost the focus of intestinal metaplasia upon deeper sectioning for *** AB and CDX2 were negative in 43 out of 48(89.6%) NBE *** NBE patients(10.4%) were falsely positive for AB due to the presence of EG and CB in these *** cases were all CDX2 *** addition,5 AB negative NBE were found to be CDX2 *** on these results the CDX2 immunostain had similar sensitivity but higher specificity(100% vs about 91%) than AB in detecting intestinal type metaplasia in these *** data shows that CDX2 has a better ppV in detecting intestinal metaplasia as compared to AB(95.6% vs 71.5%,respectively).CONCLUSION:CDX2 has a better positive predictive value than AB in detecting intestinal ***2may be useful when challenged by gastro-esophageal biopsies containing mimikers of BE.

关键词： Barrett’s esophagus Alcian blue pH 2.5 CDX2 Intest

Subacute fulminant hepatic failure with intermittent fever

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Hepatobiliary & pancreatic Diseases International 2009年第6期8卷 657-659页

作者： Joyce E.johnson Molecular Infectious Diseases Laboratory and Molecular Epidemiology Medical CenterVanderbilt University

BACKGROUND: Viral hepatitis B accounts for over 80% of acute hepatic failures in China and the patients die mainly of its complications. A patient with hepatic failure and fever is not uncommon, whereas repeated fever is rare. METHODS: A 32-year-old female was diagnosed with subacute hepatic failure and hepatitis B viral infection because of hyperbilirubinemia, coagulopathy, hepatic encephalopathy, serum anti-HBs-positive without hepatitis B vaccination, and typical intrahepatic pathological features of chronic hepatitis B. plasma exchange was administered twice and she awoke with hyperbilirubinemia and discontinuous fever. RESULTS: Urethritis was confirmed and medication-induced fever and/or spontaneous bacterial peritonitis (Gram-negative bacillus infection) was suspected. The patient was treated with antibiotics, steroids and a Chinese herbal medicine, matrine, for three months and she recovered. CONCLUSION: The survival rate of patients with hepatic failure might be improved with comprehensive supporting measures and appropriate, timely management of complications.

关键词： acute hepatic failure intermittent fever plasma exchange matrine

Creating a Digital preservation Network with Shared Stewardship and Cost： The Experience of partnerships in the National Digital Information Infrastructure and preservation program

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现代图书情报技术 2008年第1期 102-105页

作者： MOLLY johnson Director Digital Resource Management and Planning Office of Strategic Initiatives Library of Congress USA

The National Digital Information Infrastructure and preservation program (NDIIpp) was initiated in December 2000 when the U.S. Congress authorized the Library of Congress to work with a broad range of institutions to develop a national strategy for the preservation of important at-risk born digital content. Guided by a strategy of broad collaborations and iterative learning, the Library of Congress began catalyzing a national network of partners dedicated to collecting and preserving important born-digital information. Over the last six years, the Library and its partners have been engaged in learning through action. Our investments in preservation partnerships, public policy deliberations related to intellectual property challenges, basic technical research, and network architecture models have increased our understanding of the sustaining roles and functions for a national network of diverse stakeholders. The emerging network of networks is complex and inclusive of a variety of stakeholders: content producers, content stewards and service providers from the public and private sectors.

关键词：数字资源长期保存网络设计知识产权公共管理 NDIIpp