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41.
Carlos G PinheiroJr Eduardo LM Naves Pierre Pino Etienne Losson Adriano O Andrade Guy Bourhis 《Biomedical engineering online》2011,10(1):31
We have now sufficient evidence that using electrical biosignals in the field of Alternative and Augmented Communication is
feasible. Additionally, they are particularly suitable in the case of people with severe motor impairment, e.g. people with
high-level spinal cord injury or with locked-up syndrome. Developing solutions for them implies that we find ways to use sensors
that fit the user's needs and limitations, which in turn impacts the specifications of the system translating the user's intentions
into commands. After devising solutions for a given user or profile, the system should be evaluated with an appropriate method,
allowing a comparison with other solutions. This paper submits a review of the way three bioelectrical signals - electromyographic,
electrooculographic and electroencephalographic - have been utilised in alternative communication with patients suffering
severe motor restrictions. It also offers a comparative study of the various methods applied to measure the performance of
AAC systems. 相似文献
42.
43.
Glenn E. Stauffer Duane R. Diefenbach Matthew R. Marshall Daniel W. Brauning 《The Journal of wildlife management》2011,75(3):548-557
Grasslands resulting from surface mine reclamation support grassland songbird populations in several midwestern and eastern states in the United States, especially where reclaimed mines are large (>1,000 ha). However, most reclaimed surface mines in Pennsylvania are small (<200 ha), and nest success is unknown. We evaluated nest success of grasshopper (Ammodramus savannarum), Henslow's (A. henslowii), and Savannah sparrows (Passerculus sandwichensis) on 4 reclaimed surface mines (50–180 ha) in western Pennsylvania, USA from 2006 to 2007. Overall nest success based on mean covariate values was 0.435 (95% CI = 0.376–0.504) for grasshopper sparrows, 0.396 (95% CI = 0.295–0.533) for Henslow's sparrows, and 0.158 (95% CI = 0.063–0.392) for Savannah sparrows. These estimates of nest success are comparable to those on larger reclaimed mines and other habitats. Grasshopper and Henslow's sparrow nests that were well concealed were less likely to fail than highly visible nests (βvisible = −0.028, CI = −0.051 to −0.005 for grasshopper sparrows; βvisible = −0.063, CI = −0.112 to −0.014 for Henslow's sparrows), and nests in areas with surrounding deep litter were more likely to fail than nests in areas with shallow litter (βlitterD = −0.145, CI = −0.335 to 0.045 for grasshopper sparrows; βlitterD = −0.676, CI = −1.187 to −0.116 for Henslow's sparrows). Savannah sparrow nests in areas with high visual obstruction by vegetation were less likely to fail than nests in areas with sparse and short vegetation (βVisOb = 0.048, CI = 0.006–0.091). Daily probability of survival for grasshopper sparrow nests was greatest early and late in the breeding season, and Savannah sparrow nest survival followed a decreasing linear trend. Nest survival of Henslow's sparrows was greater on warm days (βtemp = 0.197, CI = 0.014–0.379), whereas for Savannah sparrows nest survival decreased on warm days and on days with rain, but for Savannah sparrows confidence intervals of weather effects included zero (βtemp = −0.098, CI = −0.246 to 0.050; βrain = 3.13, CI = −14.19 to 20.45). We suggest that small reclaimed surface mine grasslands can provide valuable nesting habitat and could be important to the conservation of grassland bird populations. Because nest success can increase in the latter part of the nesting season, agricultural disturbances or management activities in mid- to late summer could adversely affect reproductive success. © 2011 The Wildlife Society. 相似文献
44.
Hernández Pérez A E Cerna Chávez JC Delgado Ortiz M Beltrán Beache LM Tapia Vargas YM Ochoa Fuentes 《Phyton》2019,88(1):11-13
Mexico is the main producer, consumer and exporter
of avocado in the world, being Michoacan the main producer state
contributing more than 80% of the national production. There
are phytopathogens that decimate the production causing the
death of the tree. Root samples were collected in avocado trees
that showed the characteristic symptomatology of the disease
known as avocado sadness, the sampling was carried out in four
of the main avocado producing towns, in the state of Michoacan,
Mexico. The isolation consisted in sowing root tissue in Petri
dishes with V8®-PARPH culture medium, subsequently they were
identified morphologically and for species level it was determined
by molecular biology, with the PCR-ITS technique. Pathogenicity
tests were performed in triplicate with avocado seedlings with more
than six leaves. After 24 hours, the inoculated plants expressed
decay in the apical part, after 120 hours the leaves showed yellowing
and after 15 days there was a generalized wilt on the stem and
leaves, re-isolating the phytopathogen Phytopythium vexans.
This study confirms the first report of the oomycete P. vexans
affecting avocado trees in the most important producing region of
the Mexican Republic. 相似文献
45.
46.
Differentiation of Type 1 ILCs from a Common Progenitor to All Helper-like Innate Lymphoid Cell Lineages 总被引:1,自引:0,他引:1
47.
J Hartmann TV Tran J Kaudeer K Oberle J Herrmann I Quagliano T Abel A Cohnen V Gatterdam A Jacobs B Wollscheid R Tampé C Watzl A Diefenbach J Koch 《The Journal of biological chemistry》2012,287(37):31527-31539
The natural cytotoxicity receptors are a unique set of activating proteins expressed mainly on the surface of natural killer (NK) cells. The human natural cytotoxicity receptor family comprises the three type I membrane proteins NKp30, NKp44, and NKp46. Especially NKp30 is critical for the cytotoxicity of NK cells against different targets including tumor, virus-infected, and immature dendritic cells. Although the crystal structure of NKp30 was recently solved (Li, Y., Wang, Q., and Mariuzza, R. A. (2011) J. Exp. Med. 208, 703-714; Joyce, M. G., Tran, P., Zhuravleva, M. A., Jaw, J., Colonna, M., and Sun, P. D. (2011) Proc. Natl. Acad. Sci. U.S.A. 108, 6223-6228), a key question, how NKp30 recognizes several non-related ligands, remains unclear. Therefore, we investigated the parameters that impact ligand recognition of NKp30. Based on various NKp30-hIgG1-Fc fusion proteins, which were optimized for minimal background binding to cellular Fcγ receptors, we identified the flexible stalk region of NKp30 as an important but so far neglected module for ligand recognition and related signaling of the corresponding full-length receptor proteins. Moreover, we found that the ectodomain of NKp30 is N-linked glycosylated at three different sites. Mutational analyses revealed differential binding affinities and signaling capacities of mono-, di-, or triglycosylated NKp30, suggesting that the degree of glycosylation could provide a switch to modulate the ligand binding properties of NKp30 and NK cell cytotoxicity. 相似文献
48.
Eleonore S Köhler Selvakumari Sankaranarayanan Christa J van Ginneken Paul van Dijk Jacqueline LM Vermeulen Jan M Ruijter Wouter H Lamers Elisabeth Bruder 《BMC developmental biology》2008,8(1):107
Background
Milk contains too little arginine for normal growth, but its precursors proline and glutamine are abundant; the small intestine of rodents and piglets produces arginine from proline during the suckling period; and parenterally fed premature human neonates frequently suffer from hypoargininemia. These findings raise the question whether the neonatal human small intestine also expresses the enzymes that enable the synthesis of arginine from proline and/or glutamine. Carbamoylphosphate synthetase (CPS), ornithine aminotransferase (OAT), argininosuccinate synthetase (ASS), arginase-1 (ARG1), arginase-2 (ARG2), and nitric-oxide synthase (NOS) were visualized by semiquantitative immunohistochemistry in 89 small-intestinal specimens. 相似文献49.
LM Harris L Blank RP Desai NE Welker ET Papoutsakis 《Journal of industrial microbiology & biotechnology》2001,27(5):322-328
The effect of solR inactivation on the metabolism of Clostridium acetobutylicum was examined using fermentation characterization and metabolic flux analysis. The solR-inactivated strain (SolRH) of this study had a higher rate of glucose utilization and produced higher solvent concentrations
(by 25%, 14%, and 81%, respectively, for butanol, acetone, and ethanol) compared to the wild type. Strain SolRH(pTAAD), carrying
a plasmid-encoded copy of the bifunctional alcohol/aldehyde dehydrogenase gene (aad) used in butanol production, produced even higher concentrations of solvents (by 21%, 45%, and 62%, respectively, for butanol,
acetone, and ethanol) than strain SolRH. Clarithromycin used for strain SolRH maintenance during SolRH(pTAAD) fermentations
did not alter product formation; however, tetracycline used for pTAAD maintenance resulted in 90% lower solvent production.
Journal of Industrial Microbiology & Biotechnology (2001) 27, 322–328.
Received 12 September 2000/ Accepted in revised form 21 July 2001 相似文献
50.
Joost LM Vissers Betty CAM van Esch Prescilla V Jeurink Gerard A Hofman Antoon JM van Oosterhout 《Respiratory research》2004,5(1):21
BackgroundPreviously, we demonstrated that OVA-loaded macrophages (OVA-Mφ) partially suppress OVA-induced airway manifestations of asthma in BALB/c mice. In vitro studies showed that OVA-Mφ start to produce IL-10 upon interaction with allergen-specific T cells, which might mediate their immunosuppressive effects. Herein, we examined whether IL-10 is essential for the immunosuppressive effects of OVA-Mφ in vivo, and whether ex vivo stimulation of the IL-10 production by OVA-Mφ could enhance these effects.MethodsPeritoneal Mφ were loaded with OVA and stimulated with LPS or immunostimulatory sequence oligodeoxynucleotide (ISS-ODN) in vitro. The increase of IL-10 production was examined and, subsequently, ex vivo stimulated OVA-Mφ were used to treat (i.v.) OVA-sensitized mice. To further explore whether Mφ-derived IL-10 mediates the immunosuppressive effects, Mφ isolated from IL-10-/- mice were used for treatment.ResultsWe found that stimulation with LPS or ISS-ODN highly increased the IL-10 production by OVA-Mφ (2.5-fold and 4.5-fold increase, respectively). ISS-ODN stimulation of OVA-Mφ significantly potentiated the suppressive effects on allergic airway inflammation. Compared to sham-treatment, ISS-ODN-stimulated OVA-Mφ suppressed the airway eosinophilia by 85% (vs. 30% by unstimulated OVA-Mφ), IL-5 levels in bronchoalveolar lavage fluid by 80% (vs. 50%) and serum OVA-specific IgE levels by 60% (vs. 30%). Importantly, IL-10-/-Mφ that were loaded with OVA and stimulated with ISS-ODN ex vivo, failed to suppress OVA-induced airway inflammation.ConclusionsThese results demonstrate that Mφ-derived IL-10 mediates anti-inflammatory responses in a mouse model of allergic asthma, which both can be potentiated by stimulation with ISS-ODN. 相似文献