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81.
Purpose: Multipurpose robots that can perform a range of useful tasks have the potential to increase the quality of life for many people living with disabilities. Owing to factors such as high system complexity, as-yet unresolved research questions and current technology limitations, there is a need for effective strategies to coordinate the development process.

Method: Integrating established methodologies based on human-centred design and universal design, a framework was formulated to coordinate the robot design process over successive iterations of prototype development.

Results: An account is given of how the framework was practically applied to the problem of developing a personal service robot. Application of the framework led to the formation of several design goals which addressed a wide range of identified user needs. The resultant prototype solution, which consisted of several component elements, succeeded in demonstrating the performance stipulated by all of the proposed metrics.

Conclusions: Application of the framework resulted in the development of a complex prototype that addressed many aspects of the functional and usability requirements of a personal service robot. Following the process led to several important insights which directly benefit the development of subsequent prototypes.

  • Implications for Rehabilitation
  • This research shows how universal design might be used to formulate usability requirements for assistive service robots.

  • A framework is presented that guides the process of designing service robots in a human-centred way.

  • Through practical application of the framework, a prototype robot system that addressed a range of identified user needs was developed.

  相似文献   
82.
支气管哮喘(简称哮喘)与过敏性鼻炎等特应性疾病的患病率正不断上升,其发病的具体机制尚未完全清晰,主要是宿主免疫系统和环境相互作用的结果.内毒素是革兰阴性菌细胞壁上特有的结构,在外环境中内毒素几乎无处不在.内毒素对哮喘及特应性疾病而青是一把“双刃剑”,早期生活暴露于内毒素可能对疾病的发展具有保护作用;然而,暴露于高水平的内毒素环境不利于疾病的控制.  相似文献   
83.
目的了解东北地区10年间螨变应原诱发的过敏性疾病病种及特征,为该地区过敏性疾病的防治提供依据。方法采用本科信息系统数据库,统计2001年1月-2010年12月的10年间过敏性疾病患者数,并结合数据库中皮肤点刺试验(skinpricktest,SPT)结果,对尘螨变应原诱发的过敏性疾病的病种,患者的性别、年龄、职业以及环境等进行统计及分析。结果 10年间本科就诊总人数为156800人次,就诊病种主要为哮喘(51660例)、鼻炎(51266例)、荨麻疹(38787例)、皮炎(6974例)、湿疹(5483例)、结膜炎(1953例)等。156800例患者中过敏原阳性反应87975例,阳性率56%,其中屋尘螨68444例,阳性率77.8%;粉尘螨66069例,阳性率75.1%。由尘螨变应原引起过敏性疾病最多的是过敏性哮喘,其次是变应性鼻炎、荨麻疹、皮炎。结论东北地区尘螨孳生多见,易引起过敏,且患者四季均可发病。控制居室环境中的尘螨是减轻尘螨病症状、减少过敏发作的重要预防措施。  相似文献   
84.
85.
The interest of the construction industry in alkali-activated materials has increased to the extent that these materials are recognized as alternatives to ordinary Portland cement-based materials in the quest for sustainable construction. This article presents the design and construction of a prototype of an eco-friendly house built from concrete blocks produced using alkali activation technology or geopolymerization. The prototype meets the requirements of the current Colombian Regulations for Earthquake Resistant Buildings (NSR-10) and includes standards related to the performance of the materials, design, and construction method for earthquake-resistant confined masonry of one- or two-story buildings. The alkali-activated blocks were obtained from different precursors (aluminosilicates), including a natural volcanic pozzolan, ground granulated blast furnace slag, fly ash, construction and demolition waste (concrete, ceramic, brick, and mortar), and red clay brick waste. The physical-mechanical characterization of the alkali-activated blocks allowed their classification according to the structural specifications of the Colombian Technical Standard NTC 4026 (equivalent to ASTM C90). The global warming potential (GWP) or “carbon footprint” attributed to the raw materials of alkali-activated blocks was lower (25.4–54.7%) than that of the reference blocks (ordinary Portland cement concrete blocks). These results demonstrate the potential of alkali-activated materials for application in the construction of eco-friendly houses.  相似文献   
86.
Insecticide use exerts a tremendous selection force on house fly populations, but the frequencies of the initial resistance mutations may not reach high levels if they have a significant fitness cost in the absence of insecticides. However, with the continued use of the same (or similar) insecticides, it is expected that new mutations (conferring equal or greater resistance, but less of a fitness cost) will evolve. Pyrethroid insecticides target the insect voltage sensitive sodium channel (VSSC) and have been widely used for control of house flies at animal production facilities for more than three decades. There are three Vssc mutations known that cause resistance to pyrethroids in house flies: knockdown resistance (kdr, L1014F), kdr‐his (L1014H) and super‐kdr (M918T + L1014F). Whether or not there are any new mutations in house fly populations has not been examined for decades. We collected house flies from a dairy in Kansas (USA) and selected this population for three generations. We discovered multiple new Vssc alleles, including two that give very high levels of resistance to most pyrethroids. The importance of these findings to understanding the evolution of insecticide resistance, designing appropriate resistance monitoring and management schemes, and the future of pyrethroids for house fly control are discussed.  相似文献   
87.
Recent meta-analyses documented the efficacy and safety of sublingual immunotherapy (SLIT) in patients with allergic rhinitis (AR) and asthma (AA). Although SLIT appeared globally effective, the sub-analyses for single allergens provided uncertain results. This study is aimed to investigate the efficacy of SLIT with house dust mite (HDM) extracts in AR and AA through an updated reassessment of randomized controlled trials. Electronic databases were searched up to March 31, 2008, for randomized DBPC trials, assessing the efficacy of SLIT in AR and AA due to HDM sensitization. Outcomes were symptom scores and rescue medications use. For AR, eight studies fulfilled the selection criteria. A significant reduction in symptoms of AR (SMD −0.95; CI 95%−1.77 to −0.14 P  = 0.02) was found in 194 patients (adults and children) receiving SLIT compared to 188 receiving placebo. For AA, with nine studies, similar results were found for symptoms (SMD −0.95; CI 95%−1.74 to −0.15 P  = 0.02) in 243 patients (adults and children) receiving SLIT compared to 209 receiving placebo. A reduction in rescue medication use was found for AR (SMD −1.88; CI 95%−3.65 to −0.12 P  = 0.04) in 89 patients, and AA (SMD −1.48; CI 95%−2.70 to −0.26 P  = 0.02) in 202 patients. A relevant inter-study heterogeneity was detected. Promising evidence of efficacy for SLIT, using mite extract in allergic patients suffering from AR and AA, are herein shown. These findings suggest that more data are needed, derived from large-population-based high quality studies, and corroborated by objective outcomes, mainly for AA.  相似文献   
88.
Background:  The warm, humid environment in modern homes favours the dust mite population, but the effect of improved home ventilation on asthma control has not been established. We tested the hypothesis that a domestic mechanical heat recovery ventilation system (MHRV), in addition to allergen avoidance measures, can improve asthma control by attenuating re-colonization rates.
Methods:  We conducted a randomized double-blind placebo-controlled parallel group trial of the installation of MHRV activated in half the homes of 120 adults with asthma, allergic to Dermatophagoides pteronyssinus . All homes had carpets steam cleaned and new bedding and mattress covers at baseline. The primary outcome was morning peak expiratory flow (PEF) at 12 months.
Results:  At 12 months, the primary end-point; change in mean morning PEF as compared with baseline, did not differ between the MHRV group and the control group (mean difference 13.5 l/min, 95% CI: −2.6 to 29.8, P  = 0.10). However, a secondary end-point; evening mean PEF, was significantly improved in the MHRV group (mean difference 24.5 l/min, 95% CI: 8.9–40.1, P  = 0.002). Indoor relative humidity was reduced in MHRV homes, but there was no difference between the groups in Der p 1 levels, compared with baseline.
Conclusions:  The addition of MHRV to house dust mite eradication strategies did not achieve a reduction in mite allergen levels, but did improve evening PEF.  相似文献   
89.
Micrometeorites with diameter ≈100–200 μm dominate the flux of extraterrestrial matter on Earth. The vast majority of micrometeorites are chemically, mineralogically, and isotopically related to carbonaceous chondrites, which amount to only 2.5% of meteorite falls. Here, we report the discovery of the first basaltic micrometeorite (MM40). This micrometeorite is unlike any other basalt known in the solar system as revealed by isotopic data, mineral chemistry, and trace element abundances. The discovery of a new basaltic asteroidal surface expands the solar system inventory of planetary crusts and underlines the importance of micrometeorites for sampling the asteroids'' surfaces in a way complementary to meteorites, mainly because they do not suffer dynamical biases as meteorites do. The parent asteroid of MM40 has undergone extensive metamorphism, which ended no earlier than 7.9 Myr after solar system formation. Numerical simulations of dust transport dynamics suggest that MM40 might originate from one of the recently discovered basaltic asteroids that are not members of the Vesta family. The ability to retrieve such a wealth of information from this tiny (a few micrograms) sample is auspicious some years before the launch of a Mars sample return mission.  相似文献   
90.
Background Specifically designed recombinant allergens with reduced IgE reactivity are promising candidates for a more defined, effective, and safer specific immunotherapy (SIT).
Objective We sought to obtain hypoallergenic hybrid molecules which could potentially be applied to house dust mite (HDM) allergy treatment.
Methods Two hybrid molecules (QM1 and QM2) derived from the two major Dermatophagoides pteronyssinus allergens, Der p 1 and Der p 2, were engineered by PCR, produced in Escherichia coli , and purified. The overall IgE-binding capacity of the hybrids was compared with their single components by Western blot, specific IgE, skin prick test (SPT), and IgE-inhibition assays. T cell proliferation assay were performed to confirm their retention of T cell reactivity. Immune responses to the hybrid molecules were studied in BALB/c mice.
Results The IgE reactivity of both hybrid proteins was strongly reduced as evaluated by in vitro methods. Furthermore, in vivo SPTs performed on 106 HDM-allergic patients showed that the hybrid proteins had a significantly lower potency to induce cutaneous reactions than the individual components. Hybrid molecules induced higher T cell proliferation responses than those produced by an equimolecular mixture of Der p 1 and Der p 2. Immunization of mice with the hybrid proteins induced Der p 1- and Der p 2-specific IgG, which inhibited the binding of allergic patients' IgE to these natural allergens.
Conclusion QM1 and QM2 hybrids exhibited less IgE-binding activity but preserved immunogenicity and fulfilled the basic requirements for hypoallergenic molecules suitable for a future SIT of HDM allergy.  相似文献   
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