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色谱 2012年第11期30卷 1194-1202页

作者： André Moreni LOPES Jorge Sánchez ROMEU Rolando Páez MEIRELES gabriel Marquez PERERA Rolando Perdomo MORALES Adalberto PESSOA Lourdes Zumalacárregui CáRDENAS Department of Biochemical and Pharmaceutical Technology School of Pharmaceutical SciencesUniversity of So Paulo(FCF/USP) Purification Development Department Center for Genetic Engineering and Biotechnology(CIGB) Center for Pharmaceuticals Research and Development(CIDEM) Higher Polytechnic Institute José Antonio Echeverría(CUJAE)

Endotoxins(also known as lipopolysaccharides(LPS)) are undesirable by-products of recombinant proteins,purified from Escherichia coli.LPS can be considered stable under a wide range of temperature and pH,making their removal one of the most difficult tasks in downstream processes during protein purification.The inherent toxicity of LPS makes their removal an important step for the application of these proteins in several biological assays and for a safe parenteral administration.Immobilized metal affinity chromatography(IMAC) enables the affinity interactions between the metal ions(immobilized on the support through the chelating compound) and the target molecules,thus enabling high-efficiency separation of the target molecules from other components present in a mixture.Affinity chromatography is applied with Ca2+-iminodiacetic acid(IDA) to remove most of the LPS contaminants from the end product(more than90%).In this study,the adsorption of LPS on an IDA-Ca2+ was investigated.The adsorption Freundlich isotherm of LPS-IDA-Ca2+ provides a theoretical basis for LPS removal.It was found that LPS is bound mainly by interactions between the phosphate group in LPS and Ca2+ ligands on the beads.The factors such as pH(4.0 or 5.5) and ionic strength(1.0 mol/L) are essential to obtain effective removal of LPS for contaminant levels between endotoxin' concentration values less than100 EU/mL and 100 000 EU/mL.This new protocol represents a substantial advantage in time,effort,and production costs.

关键词： immobilized metal affinity chromatography(IMAC) lipopolysaccharides(LPS) endotoxin removal recombinant proteins isotherms protein purification

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加西亚·马尔克斯：我的告别信

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英语学习 2016年第9期 34-36页

作者： gabriel Garcia marquez 张燕

1．如果上帝一时忘记了我现在的样子，再多赐予我一段时间的话，我一定尽力不辜负这一段时光。2．我评判事物的标准不再是它本身的价值，而是它代表的意义。merit：价值，功过。3．如果上帝赏我一段生命，我会简装素服，在阳光下袒露的... 详细信息

1．如果上帝一时忘记了我现在的样子，再多赐予我一段时间的话，我一定尽力不辜负这一段时光。2．我评判事物的标准不再是它本身的价值，而是它代表的意义。merit：价值，功过。3．如果上帝赏我一段生命，我会简装素服，在阳光下袒露的不仅是身体，还有我的灵魂。

关键词：马尔克斯告别信加西亚上帝价值功过

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Pseudostress-BasedMixed Finite Element Methods for the Stokes Problem in Rn with Dirichlet Boundary Conditions.I:A Priori Error Analysis

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Communications in Computational Physics 2012年第6期12卷 109-134页

作者： gabriel N.Gatica Antonio marquez Manuel A.Sanchez CI2MA and Departamento de Ingenier´ıa Matem´atica Universidad de Concepci´onCasilla 160-CConcepcionChile Departamento de Construcci´on e Ingenier´ıa de Fabricacion Universidad de OviedoOviedoEspa-na.

We consider a non-standard mixed method for the Stokes problem in Rn,n∈{2,3},with Dirichlet boundary conditions,in which,after using the incompressibility condition to eliminate the pressure,the pseudostress tensor s and the velocity vector u become the only unknowns.Then,we apply the Babuˇska-Brezzi theory to prove the well-posedness of the corresponding continuous and discrete formulations.In particular,we show that Raviart-Thomas elements of order k≥0 for s and piecewise polynomials of degree k for u ensure unique solvability and stability of the associated Galerkin scheme.In addition,we introduce and analyze an augmented approach for our pseudostress-velocity formulation.The methodology employed is based on the introduction of the Galerkin least-squares type terms arising from the constitutive and equilibrium equations,and the Dirichlet boundary condition for the velocity,all of them multiplied by suitable stabilization parameters.We show that these parameters can be chosen so that the resulting augmented variational formulation is defined by a strongly coercive bilinear form,whence the associated Galerkin scheme becomes well posed for any choice of finite element subspaces.For instance,Raviart-Thomas elements of order k≥0 for s and continuous piecewise polynomials of degree k+1 for u become a feasible choice in this case.Finally,extensive numerical experiments illustrating the good performance of the methods and comparing them with other procedures available in the literature,are provided.

关键词： Mixed finite element pseudostress incompressible flow

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Challenges associated with numerical back analysis in rock mechanics

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第6期14卷 2058-2071页

作者： gabriel Walton Sankhaneel Sinha Department of Geology and Geological Engineering Colorado School of MinesGoldenCO80401USA

Numerical back analysis is a valuable tool available to rock mechanics researchers and practitioners.Recent studies related to back analysis methods focused primarily on applications of increasingly sophisticated optimization algorithms(primarily machine learning algorithms)to rock mechanics problems.These methods have typically been applied to relatively simple problems;however,more complex back analyses continue to be conducted primarily through ad hoc manual trial-and-error processes.This paper provides a review of the basic concepts and recent developments in the field of numerical back analysis for rock mechanics,as well as some discussion of the relationship between back analysis and more broadly established frameworks for numerical modelling.The challenges of flexible constraints,non-uniqueness,material model limitations,and disparate data sources are considered,and representative case studies are presented to illustrate their impacts on back analyses.The role of back analysis(or“model calibration”)in bonded particle modelling(BPM),bonded block modelling(BBM),and synthetic rock mass(SRM)modelling is also considered,and suggestions are made for further studies on this topic.

关键词： Back analysis Numerical modelling Inversion Case studies

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Surgical Infection Society guidelines on antibiotic use in gallstone surgery: high time we crack down on prophylactic antibiotics

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Hepatobiliary Surgery and Nutrition 2022年第6期11卷 893-895页

作者： gabriel Sandblom Department of Clinical Science and Education SödersjukhusetKarolinska InstitutetStockholmSweden Department of Surgery SödersjukhusetStockholmSweden

There is a great need for a more stringent and uniform use of antibiotic prophylaxis in general surgery.The decision to prescribe antibiotics is often made based on local routines or poorly defined reasons for prophyl... 详细信息

关键词： surgery routine Surgical

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Dietary supplementation with branchedchain amino acids enhances milk production by lactating sows and the growth of suckling piglets

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Journal of Animal Science and Biotechnology 2022年第6期13卷 1857-1870页

作者： Reza Rezaei Ana San gabriel Guoyao Wu Department of Animal Science Texas A&M UniversityCollege StationTX 77843USA Ajinomoto Co. Inc1-15-1 KyobashiChuokuTokyo 104-8315Japan

Background:Under current dietary regimens,milk production by lactating sows is insufficient to sustain the maximal growth of their piglets.As precursors of glutamate and glutamine as well as substrates and activators of protein synthesis,branched-chain amino acids(BCAAs)have great potential for enhancing milk production by sows.Methods:Thirty multiparous sows were assigned randomly into one of three groups:control(a corn-and soybean meal-based diet),the basal diet+1.535%BCAAs;and the basal diet+3.07%BCAAs.The ratio(g/g)among the supplemental L-isoleucine,L-leucine and L-valine was 1.00:2.56:1.23.Diets were made isonitrogenous by the addition of appropriate amounts of L-alanine.Lactating sows had free access to drinking water and their respective diets.The number of live-born piglets was standardized to 9 per sow at d 0 of lactation(the day of parturition).On d 3,15 and 29 of lactation,body weights and milk consumption of piglets were measured,and blood samples were obtained from sows and piglets 2 h and 1 h after feeding and nursing,respectively.Results:Feed intake did not differ among the three groups of sows.Concentrations of asparagine,glutamate,glutamine,citrulline,arginine,proline,BCAAs,and many other amino acids were greater(P<0.05)in the plasma of BCAA-supplemented sows and their piglets than those in the control group.Compared with the control,dietary supplementation with 1.535%and 3.07%BCAAs increased(P<0.05)concentrations of free and protein-bound BCAAs,glutamate plus glutamine,aspartate plus asparagine,and many other amino acids in milk;milk production by 14%and 21%,respectively;daily weight gains of piglets by 19%and 28%,respectively,while reducing preweaning mortality rates by 50%and 70%,respectively.Conclusion:Dietary supplementation with up to 3.07%BCAAs enhanced milk production by lactating sows,and the growth and survival of their piglets.

关键词： Branched-chain amino acids Lactation Milk synthesis Milk yield Neonatal growth Sow

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Innovating for Health in China’s Greater Bay Area

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China CDC weekly 2022年第1期4卷 1-3页

作者： Feichau Pang Puihong Chung gabriel M Leung School of Public Health LKS Faculty of MedicineThe University of Hong KongHong KongChina

The Success of World Metropolitan and Bay Areas The Tokyo Bay Area,the New York Metropolitan Area,and the San Francisco Bay Area are leading regions for science and technology.They share an economic transformation from industrial or manufacturing bases to predominantly service-based economies with this sector contributing 75%of their gross domestic product(GDP)in 2020.Technology companies in these locations accounted for 60%of the revenue of the top 100 global tech companies in 2018(1).The success of these locations stems from the convergence of academia,technology giants,government support,and a high density of investors,as well as innovative entrepreneurs(2).

关键词： companies revenue bases

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Silicon Photoelectrodes Prepared by Low-Cost Wet Methods for Solar Photoelectrocatalysis

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Accounts of Materials Research 2023年第2期4卷 133-142页

作者： Bruno Fabre gabriel Loget CNRS ISCR(Institut des Sciences Chimiques de Rennes)-UMR6226Univ RennesRennes F-35000France

The electrochemical conversion of sunlight by photoelectrochemical cells(PECs)is based on semiconductor electrodes that are interfaced with a liquid electrolyte.This approach is highly promising,first,because it can be employed for the generation of a chemical fuel(e.g.,H2)to store solar energy that can be used on-demand to generate electricity when the sun is not available.Second,it can be seen as a concept reminiscent of photosynthesis,where CO_(2) is converted into a valuable feedstock by solar energy.Thus,photoelectrochemical cells are sometimes referred to as“artificial leaves”.Silicon,being the main semiconductor in the electronics and photovoltaic sector,is a prime candidate to be used as the light absorber and the substrate for building photoelectrochemical cells.However,Si alone has“poor-to-no photoelectrochemical performance”.This is caused by its weak electrocatalytic activity for cathodic reactions(namely,the hydrogen evolution reaction(HER),the CO_(2) reduction reaction(CDRR),and the N2 reduction reaction)and by its deactivation in the anodic regime,prohibiting its use for the oxygen evolution reaction(OER).This latter reaction is essential for supplying electrons to generate a solar fuel.Due to these problems,layers that both protect and are catalytically active are typically employed on Si photoelectrodes but require rather sophisticated manufacturing processes(e.g.,atomic layer or electron beam deposition),which hinders research and innovation in this field.Nevertheless,our group and others have demonstrated that these layers are not always required and that highly active and stable Si-based photoelectrodes can be manufactured using simple wet processes,such as drop casting,electroless deposition,or aqueous electrodeposition.In this Account,we first introduce the topic and the possible structures that can be easily obtained starting from commercial Si wafers.Then,we discuss strategies that have been employed to manufacture photocathodes based on p-type Si.Among these,we describe Si photocathodes c

关键词： field starting absorber

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Development of an instrument to measure patients' attitudes towards involuntary hospitalization

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World Journal of Psychiatry 2017年第2期7卷 89-97页

作者： Adel gabriel Departments of Psychiatry and Community Health Sciences University of Calgary

AIM To construct and assess the psychometric properties of an instrument to measure patients' attitudes towards involuntary hospitalization. METHODS This is a two phase study. In the first phase, based on comprehensive literature review, a twenty one item scale to measure patients' attitudes to involuntary admission was constructed. Forensic and inpatient Psychiatrists, patients' advocates and legal experts(n = 15) were invited to participate in the validation process of the written instrument, by formally rating each item of the instrument for its relevancy in measuring patients' attitudes to involuntary admission. In the second phase of the project, the instrument was administered to a sample of eighty consecutive patients, who were admitted involuntarily to an acute psychiatric unit of a teaching hospital. All patients completed the constructed attitudes towards involuntary admission scale, and the client satisfaction questionnaire. RESULTS Responses from psychiatry and advocacy experts provided evidence for face and content validity for the constructed instrument. The internal consistency reliability of the instrument is 0.84(Chronbach' alpha), factor analysis resulted in three correlated, and theoretically meaningful factors. There was evidence for content, convergent, and concurrent validity.CONCLUSION A reliable twenty one item instrument scale to measure patients' attitudes to involuntary admission was developed. The developed instrument has high reliability, there is strong evidence for validity, and it takes ten minutes to complete.

关键词： Scales Mmeasurements Patients’attitudes Involuntary admission Psychiatric

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A case study on the efficacy of different roof bolting schemes in Lhoist North America’s Crab Orchard Mine

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International Journal of Mining Science and Technology 2020年第1期30卷 99-104页

作者： Reece Kurre gabriel Walton Stantec Consulting Services Inc. Walnut CreekCA 94597USA Department of Geology and Geological Engineering Colorado School of MinesGoldenCO 80401USA

Roof bolting has long been used in underground mines across the world to provide ground support.Modern roof bolts are cheap and easy to install with the use of specialized machines as a part of the production cycle. Lhoist North America’s Crab Orchard Mine is an underground room and pillar limestone mine that uses mechanically anchored roof bolts for ground support. The mine currently employs two different roof bolting patterns: a standard 1.5 × 1.5 m pattern, and another 0.8 × 0.8 m pattern for use in areas with particularly hazardous roof conditions. The purpose of this study is to evaluate the relative effectiveness of each bolting pattern. A series of numerical models were created using Roc Science’s RS2. The models were based on a symmetrical section of the mine at its deepest point, and were modeled using generalized Hoek-Brown failure criterion along with a discrete fracture network. A series of sensitivity analyses were performed on the models by varying parameters such as joint friction angle, crack persistence, joint randomization, and tensile strength of the limestone. Based on the results of the original models and sensitivity analyses, it appeared that the standard bolting pattern provided sufficient roof support capacity under almost all the expected conditions at the mine, since safety factors below the design value of 1.5 were only found for individual bolts in a few of the worst test cases considered.These results can help improve the mine’s productivity and reduce operating costs without compromising safety.

关键词： Numerical modeling Mining Roof bolting Roof stability Analysis RocScience’s RS2 Underground stone

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