检索结果-南通市图书馆

Emerging Challenges in the Completion of Construction Projects through Public Private Partnerships: Empirical Literature Review

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Building Construction and Planning Research 2020年第4期8卷 263-272页

作者： pamela Akinyi Oyieyo School of Open and Distance eLearning University of Nairobi Nairobi Kenya

The process of engaging private sector in the provision of public infrastructure can improve economic value in service delivery and enable the government to utilize the capabilities and expertise held by private sector. This has a positive impact on the public in terms of improving their well-being. This literature review attempts to compare the challenges encountered in implementation of PPP projects across the world, with a view to determining cross cutting challenges and recommendations for developing countries. A literature review was conducted for empirical studies focusing on construction projects. The studies are reviewed by analyzing the methodology used and conclusions made to identify the geographical study area, Public Private Partnership project financing model, emerging challenges and recommendation for future project management. The literature search was based on four keywords: construction projects, completion of construction projects, public private partnership, challenges in construction projects. Thus, a total of 11 empirical studies were identified for review in Europe, Asia and Africa. The review revealed that most risk factors affecting project completion can be categorized as human and organizational factors and unknown geotechnical conditions that were not known beforehand. Specifically, project owners’ interference was also attributable to delays with the delays having significant implications for project execution. Risks have great impact on the performance of construction projects because they affect their quality, time and cost. The general remedy to such potential risk factors is adoption of reliable prediction mechanisms which would estimate those factors using a probabilistic model that does not rely on expert judgments as they tend to be unreliable.

关键词： Construction Projects Completion of Construction Projects Public Private Partnership Challenges in Construction Projects

Following the Threads

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Beijing Review 2024年第3期67卷 44-45页

作者： pamela Tobey 不详

China has a wide variety of items on its official intangible cultural heritage(ICH)list,and one of the most colorful folk crafts included is the embroidery of the Yi ethnic *** a history stretching back 1,700 years,this art form has been handed down from mother to daughter and its designs reflect their close relationship with nature.

关键词： mother daughter stretching

Ecological succession of benthic organisms on niche-type artificial reefs

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Ecological Processes 2020年第1期9卷 433-442页

作者： María-Isabel Toledo pamela Torres Cristina Díaz Victor Zamora Jesús López Germán Olivares Escuela de Ciencias del Mar Facultad de Ciencias del Mar y GeografíaPontificia Universidad Católica de ValparaísoValparaísoChile

As part of efforts to restore fishery resources and recover damaged coastal ecosystems,artificial reefs are often anchored on the seafloor in coastal zones,to provide new habitats for marine *** aim of the study was to describe the structure of a community of benthic invertebrates colonising a niche-type artificial reef(AATN in Spanish).Nine structures were anchored at depths of 16±1.5 m for 99 weeks(22 months)in the Area of Benthic Resource Management and Exploitation(AMERB)in coastal waters of the Region of Bio Bio,*** results showed that,at 3 months from submersion of the NTAR,much of the artificial substrate remained bare and there were only low levels of specimens of Balanus ***,showing mean coverage of 11.26%,and even lower proportions of Rhodophyta,with mean coverage of 0.34%.At 6 months,the presence of hydrozoans was seen,decreasing the coverage of the barnacles,which was aided further at 8 months with the arrival of barnacle predatory *** 8 months,new benthic invertebrates appeared and competed for the *** included sponges and *** 99 weeks,the hydrozoans dominated the substrate,followed by barnacles and Rhodophyta,the first colonising organisms,leading to colonisation by motile macro-invertebrates,mainly consisting of crustaceans,echinoderms and *** AATN artificial system provides an ideal substrate for the development of early ecological succession and the use of this technology should be feasible in the recovery process of habitat damaged by anthropogenic actions and climate change.

关键词： Artificial reefs Ecological succession Colonisation Benthic organisms Balanus sp. Rhodophyta Hydrozoans

Porphyromonas gingivalis Resistance to Polymyxin B Is Determined by the Lipid A 4’-Phosphatase, PGN_0524

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Oral Science 2009年第3期1卷 126-135页

作者： Stephen R. Coats Thao T. To Sumita Jain pamela H. Braham Richard P. Darveau Department of Periodontics School of Dentistry University of Washington Seattle USA

Aim To elucidate the genetic basis for the pronounced resistance that the oral pathogen, Porphyromonas gingivalis （P. gingivalis）, exhibits towards the cationic antimicrobial peptide, polymyxin B. Methodology A genetic screen of P. gingivalis clones generated by a Tn4400-based random insertion mutagenesis strategy was performed to identify bacteria harboring novel genetic mutations that render P. gingivalis susceptible to killing by the cationic antimicrobial peptide, polymyxin B （PMB, 50μg·mL^-1）. Results P. gingivalis （ATCC 33277） is unusually resistant to the cationic antimicrobial peptide, PMB at relatively high concentrations （200μg·mL^-1）. Approximately 2,700 independent Tn4400 ＇-derived mutants ofP. gingivalis were examined for increased sensitivity to PMB killing at a relatively low dose （50 μg·mL^-1）. A single PMB-sensitive mutant was obtained in this phenotypic screen. We determined that the Tn4400＇ transposon was integrated into the gene encoding the lipid A 4＇-phosphatase, PGN 0524, demonstrating that this insertion event was responsible for its increased susceptibility of this clone to PMB-dependent killing. The resulting mutant strain, designated 0524-Tn4400＇, was highly sensitive to PMB killing relative to wild-type P. gingivalis, and exhibited the same sensitivity as the previously characterized strain, 0524KO, which bears a genetically engineered deletion in the PGN_0524 locus. Positive ion mass spectrometric structural （MALDI-TOF MS） analyses revealed that lipid A isolates from 0524-Tn4400＂ and 0524KO strains displayed strikingly similar MALDI-TOF MS spectra that were substantially different from the wildtype P gingivalis lipid A spectrum. Finally, intact 0524- Tn4400＇ and 0524KO mutant bacteria, as well as their corresponding LPS isolates, were significantly more potent in stimulating Toll-like receptor 4 （TLR4）-dependent E-selectin expression in human endothelial cells relative to intact wild-type P.. gingivalis or its corresponding LPS isolate.

关键词： P. gingivalis antimicrobial peptide lipid A phosphatase polymyxin B transposon lipopolysaccharide

Paladin, a tyrosine phosphatase-like protein, is required for XA21-mediated immunity in rice

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Plant Communications 2021年第4期2卷 116-126页

作者： Tsung-Chi Chen Mawsheng Chern Michael Steinwand Deling Ruan Yu Wang Arkin Isharani pamela Ronald Department of Plant Pathology and the Genome Center University of CaliforniaDavisCA 95616USA

XA21 encodes a rice immune receptor that confers robust resistance to most strains of the Gram-negative bacterium Xanthomonas oryzae ***(Xoo).XA21-mediated immunity is triggered by recognition of a small protein called RaxX-sY(required for activation of XA21-mediated immunity X,tyrosine-sulfated)secreted by *** identify components regulating XA21-mediated immunity,we generated and screened a mutant population of fast-neutron-mutagenized rice expressing Ubi:Myc-XA21 for those susceptible to ***,we report the characterization of one of these rice mutants,named sxi2(suppressor of XA21-mediated immunity-2).Whole-genome sequencing revealed that sxi2 carries a deletion of the PALADIN(PALD)gene encoding a protein with three putative protein tyrosine phosphatase-like domains(PTP-A,-B,and-C).Expression of PALD in the sxi2 genetic background was sufficient to complement the susceptible phenotype,which requires the catalytic cysteine of the PTP-A active site to restore *** coimmunoprecipitated with the full-length XA21 protein,whose levels are positively regulated by the presence of the PALD ***,we foundd that sxi2 retains many hallmarks of XA21-mediated immunity,similar to the wild *** results reveal that PALD,a previously uncharacterized class of phosphatase,functions in rice innate immunity,and suggest that the conserved cysteine in the PTP-A domain of PALD is required for its immune function.

关键词： XA21 rice bacterial blight disease Xanthomonas oryzae pv.oryzae fast-neutron mutagenesis PALD

Measures of empathy in children and adolescents:A systematic review of questionnaires

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Psychiatry 2021年第10期11卷 876-896页

作者： Gianluca Sesso Giulio Emilio Brancati pamela Fantozzi Emanuela Inguaggiato Annarita Milone Gabriele Masi Department of Clinical and Experimental Medicine University of PisaPisa 56100Italy IRCCS Fondazione Stella Maris Scientific Institute of Child Neurology and PsychiatryCalambrone 56128Italy

BACKGROUND Empathy has long been considered a multidimensional construct,encompassing cognitive,affective and behavioral *** in empathic competences in early childhood contribute to psychopathology,and have been variably implicated in several clinical conditions,such as autism spectrum disorders(ASD)and conduct *** To identify and describe empirically validated questionnaires assessing empathy in children and adolescents and to provide a summary of related theoretical perspectives on empathy definitional *** A systematic review of the literature was *** bibliographic databases were searched.A total of 47 studies were selected for final analysis and 16 distinct measures were identified and *** Questionable to excellent levels of internal consistency were observed,while few studies assessed test-retest *** construct definitions only partially overlapped,affective and cognitive domains of empathy were the commonest internal factors that were often separately *** facets of the construct(i.e.,somatic empathy and sympathy)and specific clinical populations(i.e.,ASD)could be specifically addressed through more recent *** The combination of different assessment methods is recommended in order to foresee further improvements in this field and try to overcome the problem of limited convergence with more objective measures.

关键词： Empathy Assessment Child Adolescent Autistic disorder Conduct disorder

Characteristics and mechanism of Leuconostoc citreum as a novel bioflocculant for starch granules in starch production

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Food Innovation and Advances 2023年第4期2卷 291-301页

作者： Xuan Wang pamela Owusu Osei Lei Rao Xiaomeng Wu Xiaojun Liao College of Food Science and Nutritional Engineering National Engineering Research Center for Fruit&Vegetable ProcessingKey Laboratory of Fruit&Vegetable ProcessingMinistry of Agriculture and Agricultural AffairsBeijing Key Laboratory for Food Non-thermal ProcessingChina Agricultural UniversityBeijing 100083China

The Leuconostoc citreum SJ-57 strain isolated from the sweet potato starch production showed great potential as a microbiological flocculant,but its underlying flocculation mechanisms are yet *** this study,infrared spectroscopy and thermodynamic analysis were performed to elucidate the short-range and long-range interactions between *** SJ-57 and starch granules,revealing that bacteria cells bond starch granules via metal-bridging ionic bonds.A high repulsive energy barrier of~8×10^(−18)J must be overcome to initiate the flocculation ***,protease,lipase,lysozyme,dextranase,and guanidine hydrochloride were used to treat the bacterial cell,confirming that its flocculation ability originated from surface proteins,including GW structural domain proteins,DnaK,GroEL,elongation factor Tu,and lysozyme *** primary flocculation mechanisms of *** was proposed to provide a deep understanding of microbiological flocculants and a foundation for future industrial applications in starch production.

关键词： starch overcome originated

Mast cells as rapid innate sensors of cytomegalovirus by TLR3/TRIF signaling-dependent and -independent mechanisms

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Cellular & Molecular Immunology 2015年第2期12卷 192-201页

作者： Marc Becker Niels AW Lemmermann Stefan Ebert pamela Baars Angelique Renzaho Jurgen Podlech Michael Stassen Matthias J Reddehase Institute for Immunology Research Center for Immunotherapy (FZI) at the University Medical Center of the Johannes Gutenberg University Mainz Germany Institute for Virology Research Center for Immunotherapy (FZI) at the University Medical Center of the Johannes Gutenberg University Mainz Germany These authors contributed equally to this work Co-senior authors

The succinct metaphor,‘the immune system＇s loaded gun＇, has been used to describe the role of mast cells （MCs） due to their storage of a wide range of potent pro-inflammatory and antimicrobial mediators in secretory granules that can be released almost instantly on demand to fight invaders. Located at host-environment boundaries and equipped with an arsenal of pattern recognition receptors, MCs are destined to be rapid innate sensors of pathogens penetrating endothelial and epithelial surfaces. Although the importance of MCs in antimicrobial and antiparasitic defense has long been appreciated, their role in raising the alarm against viral infections has been noted only recently. Work on cytomegalovirus （CMV） infection in the murine model has revealed MCs as players in a novel cross-talk axis between innate and adaptive immune surveillance of CMV, in that infection of MCs, which is associated with MC degranulation and release of the chemokine CCL5, enhances the recruitment of protective CD8 T cells to extravascular sites of virus replication, specifically to lung interstitium and alveolar epithelium. Here, we have expanded on these studies by investigating the conditions for MC activation and the consequent degranulation in response to host infection. Surprisingly, the data revealed two temporally and mechanistically distinct waves of MC activation： an almost instant indirect activation that depended on TLR3/TRIF signaling and delayed activation by direct infection of MCs that did not involve TLR3/rRIF signaling. Cell type-specific Cre-recombination that yielded eGFP-expressing reporter virus selectively originating from MCs identified MC as a new in vivo, first-hit target cell of productive murine CMV infection.

关键词： cytomegalovirus innate immunity mast cells mast cell-specific Cre-recombination TLR3FrRIF-signaling

AIDS AWARENESS PROMOTION-BETTER LATE THAN NEVER

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Today 2003年第3期52卷 50-52页

作者： pamela LORD

“People need to know that they can be testedwithout shame;that if they are infected they will betreated;that if they fall ill,they can live safe fromdiscrimination” -Kofi Annan,Hangzhou,China,October

关键词：爱滋病中国艺术身体检测