Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Clin Infect Dis ; 73(Suppl_4): S283-S289, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34850831

RESUMO

Advanced genomics and sequencing technologies are increasingly becoming critical for global health applications such as pathogen and antimicrobial resistance (AMR) surveillance. Limited resources challenge capacity development in low- and middle-income countries (LMICs), with few countries having genomics facilities and adequately trained staff. Training research and public health experts who are directly involved in the establishment of such facilities offers an effective, but limited, solution to a growing need. Instead, training them to impart their knowledge and skills to others provides a sustainable model for scaling up the much needed capacity and capability for genomic sequencing and analysis locally with global impact. We designed and developed a Train-the-Trainer course integrating pedagogical aspects with genomic and bioinformatics activities. The course was delivered to 18 participants from 12 countries in Africa, Asia, and Latin America. A combination of teaching strategies culminating in a group project created a foundation for continued development at home institutions. Upon follow-up after 6 months, at least 40% of trainees had initiated training programs and collaborations to build capacity at local, national, and regional level. This work provides a framework for implementing a training and capacity building program for the application of genomics tools and resources in AMR surveillance.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana , Antibacterianos/farmacologia , Fortalecimento Institucional , Países em Desenvolvimento , Farmacorresistência Bacteriana/genética , Genômica , Humanos
2.
Materials (Basel) ; 14(22)2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34832387

RESUMO

To meet the high demand for lightweight energy-efficient and safe structures for transport applications, a current state-of-the-art light rail vehicle structure is under development that adopts a multi-material design strategy. This strategy creates the need for advanced multi-material joining technologies. The compatibility of the adhesive with a wide range of material types and the possibility of joining multi-material structures is also a key advantage to its success. In this paper, the feasibility of using either epoxy or polyurethane adhesive joining techniques applied to the multi-material vehicle structure is investigated. Importantly, consideration is given to the effect of variation in bond thickness for both families of structural adhesives. Multi-material adhesively bonded single lap joints with different adhesives of controlled bond thicknesses were manufactured and tested in order to experimentally assess the shear strength and stiffness. The torsional stiffness and natural frequency of the vehicle were modelled using a global two-dimensional finite element model (FEM) with different adhesive properties, and the obtained vehicle performances were further explained by the coupon-level experimental tests. The results showed that the vehicle using polyurethane adhesive with a target bond thickness of 1.0 mm allowed for optimal modal frequency and weight reduction.

3.
Soft Matter ; 14(45): 9175-9184, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30398509

RESUMO

Stress oscillation has been observed in a number of linear thermoplastic polymers during the cold-drawing process, where the polymers exhibit periodic self-excited oscillatory neck propagation. However, the origin of the mechanical stress oscillation process and its relationship with the crystalline morphology of the polymer are still under debate. In this work, we revisit the stress oscillation behavior by studying a semi-crystalline polyester, poly(butylene succinate) (PBS), a biodegradable polymer suitable for biomedical and packaging applications. Stress oscillation of PBS is observed when deformed at a range of elongation rates from 10 to 200 mm min-1, and the fluctuation magnitude decays as the deformation temperature increases from 23 to 100 °C. Periodic transparent/opaque bands form during necking of PBS, which consists of alternating regions of highly oriented crystalline zones and microcavities due to crazing and voiding, although the degree of crystallinity did not change significantly in the bands. Simultaneous small- and wide-angle X-ray scattering confirms that the alternating stress increases, as shown in the stress-strain curves, correspond to the appearance of the transparent bands in the sample, and the abrupt drop of the stress is the result of voiding during the neck propagation. The voiding and cavitation are ultimately responsible for the stress oscillation process in PBS. The in-depth analysis of this work is important in understanding and controlling the occurrence of instabilities/cavitation during polymer processing such as film blowing, biaxial stretching and injection moulding of biodegradable polymer materials.

4.
Phys Chem Chem Phys ; 15(15): 5518-29, 2013 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-23455373

RESUMO

Polyhedral oligomeric silsesquioxane (POSS) cubic cage systems (octa-n-octadecyloctasilsesquioxane, (T8C18) and octakis(n-octadecyldimethylsiloxy)octasilsesquioxane, (Q8C18)) were synthesised with eight long n-alkyl chain (R = C18H37) substituent arms, as model nano-functionalized compounds. The crystalline packing morphology of the cages was studied using time-resolved Small- and Wide-angle X-ray scattering (SAXS/WAXS), thermal and optical techniques. From thermal analysis the melting and crystallization temperatures of the Q8 cage were significantly less than those for the T8 cage. X-ray scattering showed that both cage systems have long-range crystalline ordering where the alkyl chains align in a parallel axial disposition from the POSS core giving a 'rod-like' self-assembled packing morphology. The packing length-scale can be directly related to the overall dimensions of the POSS molecules. Compared to the T8 cages, the Q8 cages pack more efficiently allowing the interdigitation of the alkyl chain arms. Different packing modes and thermal behaviour observed for the T8 and Q8 cages is directly attributed to their structural chemistry. For the Q8 cage, the presence of the OSiMe2 spacer groups which tether the alkyl chain arms to the cage (absent in the T8 cages) allows greater flexibility of the arms letting them interdigitate with each other when packing which is not observed for the analogous T8 cages.

5.
Br J Nutr ; 100(5): 1109-15, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18377694

RESUMO

The effects of incremental exercise on appetite, energy intake (EI), expenditure (EE) and balance (EB) in lean men and women were examined. Six men (age 29.7 (SD 5.9) years, weight 75.2 (SD 15.3) kg, height 1.75 (SD 0.11) m) and six women (age 24.7 (SD 5.9) years, weight 66.7 (SD 9.10) kg, height 1.70 (SD 0.09) m) were each studied three times during a 16 d protocol, corresponding to no additional exercise (Nex), moderate-intensity exercise (Mex; 1.5-2.0 MJ/d) and high-intensity exercise (Hex; 3.0-4.0 MJ/d) regimens. Subjects were fed to EB during days 1-2, and during days 3-16 they fed ad libitum from a medium-fat diet of constant composition. Daily EE, assessed using the doubly labelled water method, was 9.2, 11.6 and 13.7 MJ/d (P < 0.001; SED 0.45) for the women and 12.2, 14.0 and 16.7 MJ/d (P = 0.007; SED 1.11) for the men on the Nex, Mex and Hex treatments, respectively. EI was 8.3, 8.6 and 9.9 MJ/d (P = 0.118; SED 0.72) for the women and 10.6, 11.6 and 12.0 MJ/d (P = 0.031; SED 0.47) for the men, respectively. On average, subjects compensated for about 30 % of the exercise-induced energy deficit. However, the degree of compensation varied considerably among individuals. The present study captured the initial compensation in EI for exercise-induced energy deficits. Total compensation would take a matter of weeks.


Assuntos
Apetite/fisiologia , Metabolismo Energético/fisiologia , Exercício Físico/fisiologia , Comportamento Alimentar/fisiologia , Adulto , Análise de Variância , Calorimetria Indireta , Estudos Cross-Over , Dieta , Ingestão de Líquidos , Ingestão de Energia/fisiologia , Feminino , Frequência Cardíaca , Humanos , Fome , Masculino , Fatores de Tempo
6.
Br J Haematol ; 130(5): 791-4, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16115139

RESUMO

We describe a flow cytometric technique to study transfused platelets in patients. By selecting donor/recipient pairs discrepant for HLA-A2, transfused platelets were identified using anti-HLA-A2 with a detection limit of <5%, and accuracy within 4.3% of predicted (r2 > 0.96, P < 0.0001). In two of three episodes, transfused platelets were present in greater numbers than predicted from increment counts. Platelets with bound fibrinogen fell from 20.9 +/- 23.6% of donor platelets pretransfusion to 1.7 +/- 0.3% 1 h post-transfusion, whereas P-selectin-positive platelets fell gradually, from 24.1 +/- 6.7 to 7.3 +/- 3.3% at 6 h. This method avoids radio or chemical labelling, and could be used to assess novel platelet preparations post-transfusion.


Assuntos
Plaquetas/metabolismo , Antígeno HLA-A2 , Transfusão de Plaquetas , Anticorpos Monoclonais/análise , Plaquetas/imunologia , Fibrinogênio/metabolismo , Citometria de Fluxo/métodos , Antígeno HLA-A2/imunologia , Humanos , Selectina-P/análise , Ativação Plaquetária , Ligação Proteica , Sensibilidade e Especificidade
7.
Thromb Haemost ; 94(6): 1318-26, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16411412

RESUMO

Antibodies are a powerful tool for structure/function studies of platelet proteins. However, classic immunisation frequently elicits antibody responses against domains of minor functional interest. Robust strategies to generate antibodies against defined domains would be of significant interest in post-genome research. In this study, we report a new strategy using a combination of DNA vaccination and V gene phage display that allows the rapid generation of domain specific single-chain Fv antibodies (scFvs). This system was validated using the I-domain of alpha2 integrin as a model. The alpha2beta1 integrin, which is expressed on many cell types, is the dominant collagen attachment receptor on platelets, functioning in close interplay with the collagen signalling receptor glycoprotein VI. A novel set of I-domain specific antibodies was obtained by a DNA vaccination/V gene repertoire cloning approach. Mice were first immunised with a DNA vaccine in which the alpha2 I-domain is expressed as a fusion protein with fragment C of tetanus toxoid (FrC-TT). Then the heavy and kappa light chain variable gene repertoires were rescued from immune splenocytes using antibody phage display. A total of four alpha2 I-domain specific scFvs were isolated by selection on recombinant I-domain or native platelet alpha2beta1 integrin. Characterisation of the scFvs indicated that they recognised distinct epitopes that had profound differences in accessibility between native and recombinant I-domain. Our data suggest DNA immunisation and phage display represent versatile alternatives to protein immunisation and hybridoma-fusion techniques for the isolation of recombinant antibody reagents. This approach will be particularly useful for the generation of domain or splice-variant specific antibodies that recognise native protein.


Assuntos
Anticorpos Monoclonais/biossíntese , Plaquetas/imunologia , Integrina alfa2beta1/imunologia , Biblioteca de Peptídeos , Vacinas de DNA/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/química , Especificidade de Anticorpos , Sítios de Ligação de Anticorpos , Clonagem Molecular , Mapeamento de Epitopos , Humanos , Imunização/métodos , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Integrina alfa2beta1/genética , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Coelhos , Proteínas Recombinantes de Fusão
8.
Am J Clin Nutr ; 79(1): 62-9, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14684398

RESUMO

BACKGROUND: It is not clear how decreased activity quantitatively affects energy balance (EB) in subjects feeding ad libitum. OBJECTIVE: We assessed the effect of an imposed sedentary routine on appetite, energy intake (EI), EB, and nutrient balance in lean men for 7 d. DESIGN: Six men with a mean (+/-SD) age of 23.0 +/- 2.3 y, weight of 69.2 +/- 11.4 kg, and height of 1.76 +/- 0.07 m were each studied twice during a sedentary [1.4 x resting metabolic rate (RMR)] and a moderately active (1.8 x RMR) regimen. During each treatment, they resided in the whole-body indirect calorimeter for the 7 d and had ad libitum access to a medium-fat diet of constant, measurable composition. Meal size, frequency, and composition were continually monitored. Motivation to eat was recorded during waking hours. Subjects were weighed in light clothing each morning, and their weight was corrected to nude. RESULTS: Energy expenditure was 9.7 and 12.8 MJ/d [P < 0.01; SE of the difference between means (SED) = 0.41] during the sedentary and active regimens, respectively. EI was 13.5 and 14.4 MJ/d (P = 0.463, SED = 1.06), respectively. There was no regimen effect on hunger, appetite, or body weight. By day 7, cumulative EB was 26.3 and 11.1 MJ, respectively. CONCLUSIONS: Reducing a level of physical activity from 1.8 to 1.4 x RMR can markedly affect EB. A sedentary routine does not induce a compensatory reduction of EI and leads to a significantly positive EB, most of which is stored as fat.


Assuntos
Apetite , Metabolismo Basal , Metabolismo Energético , Exercício Físico , Adulto , Calorimetria Indireta , Ingestão de Alimentos , Humanos , Masculino
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...