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1.
Sensors (Basel) ; 22(19)2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-36236358

RESUMO

The present study exposes an economical and easy-to-use system to assess the heat transfer in building envelopes by determining the U-value. Nowadays these systems require long wires and a host to collect and process the data. In this work, a multi-point system for simultaneous heat flux measurement has been proposed. The aim is to reduce the long measurement time and the cost of thermal isolation evaluations in large buildings. The system proposed consists of a low-cost 3D-printed heat flux sensor integrated with a LoRa transceiver and two temperature sensors. The heat flux (HF) sensor was compared and calibrated with a commercial HF sensor from the Fluxteq brand.


Assuntos
Temperatura Alta , Coleta de Dados
2.
HardwareX ; 10: e00218, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35607673

RESUMO

Attending the latest advances in polymeric fibers, the design of low-cost, and high-quality scientific equipment for obtaining fibers seemed essential. To overcome this challenge, a 3D printable prototype was designed, assembled, and validated to obtain fibers using the SBS method. The particular configuration of the prototype consisted of controlling the process conditions such as working distance and injection flow, as well as other parameters such as RPM and the axial movement of the cylindrical collector. Thus, these parameters were automated using a microcontroller (Arduino) that receives information from an Android device with bluetooth connectivity to control each of the elements of the equipment. Subsequently, the repeatability and reproducibility of the fibers was verified using polymers such as polystyrene (PS), polysulfone (PSF) and polyethylene oxide (PEO); furthermore, PSF fibers were manufactured to analyze the influence of working distance and the axial movement of the collector on their production.

3.
J Environ Manage ; 190: 158-169, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28040591

RESUMO

Recent years have seen firms improve their environmental practices, although the question still remains as to whether or not investing in such practices is or is not beneficial or simply a matter of image. This study focuses on labour productivity as a measure of performance, and we argue that the impact of greater environmental performance on that productivity is moderated by capital intensity. A sample of 2823 plants provides empirical evidence to support our approach. Specifically, the analyses, making use of estimates based on multiple regression models, reveal that environmental management has a positive impact on labour productivity in organisations with low capital intensity, although that impact becomes negative in cases of high capital intensity.


Assuntos
Financiamento de Capital , Emprego , Meio Ambiente , Modelos Teóricos , Eficiência , Eficiência Organizacional , União Europeia , Humanos , Análise de Regressão
4.
Cryo Letters ; 35(2): 119-28, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24869644

RESUMO

BACKGROUND: Thymus lotocephalus is a rare endemic species from the Algarve, Portugal, and is legally protected by Portuguese and European legislation. OBJECTIVE: The aim is to develop a cryopreservation protocol for T. lotocephalus shoot tips, as an alternative approach for the long-term conservation of this species. METHODS: Several methods (droplet-vitrification, vitrification and encapsulation-dehydration) were tested. Conditions regarding the subculture period, cold-hardening and preculture were optimized. Cryopreserved shoot tips were also assessed for their genetic stability using RAPD markers. RESULTS: Droplet-vitrification presented the best results. The best regrowth of cryopreserved shoot tips obtained eight weeks after rewarming was 67%. This was accomplished with four weeks subculture period of in vitro-donor plants at 25 degree C, preculture of excised shoot tips for one day on MS medium containing 0.3 M sucrose, treatment in PVS2 for 60 min, and MS supplemented with 0.2 mg per L zeatin as recovery medium. The assessment using RAPD markers observed variation at a low frequency and shoots regenerated from cryopreserved apices showed normal development compared to the regular in vitro-grown shoots. CONCLUSION: Droplet-vitrification is thus a viable method for the cryopreservation of T. lotocephalus shoot tips.


Assuntos
Criopreservação , DNA de Plantas/genética , Genoma de Planta , Brotos de Planta/fisiologia , Thymus (Planta)/fisiologia , Vitrificação , Adaptação Fisiológica , Conservação dos Recursos Naturais , Crioprotetores/farmacologia , Meios de Cultura , Dessecação , Espécies em Perigo de Extinção , Instabilidade Genômica , Reguladores de Crescimento de Plantas/farmacologia , Brotos de Planta/efeitos dos fármacos , Portugal , Técnica de Amplificação ao Acaso de DNA Polimórfico , Sacarose/farmacologia , Thymus (Planta)/efeitos dos fármacos , Zeatina/farmacologia
5.
Clin Exp Rheumatol ; 30(1 Suppl 70): S162-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22640658

RESUMO

OBJECTIVES: To evaluate the performance of the Birmingham Vasculitis Activity Score (BVAS) v3 and the Disease Extent Index (DEI) for the assessment of disease activity in 4 primary childhood (c-) systemic vasculitides. METHODS: Patients fulfilling the EULAR/PRINTO/PRES (Ankara) c-vasculitis classification criteria for Henoch-Schönlein purpura (HSP), childhood (c) polyarteritis nodosa (c-PAN), c-Wegener's granulomatosis (c-WG) and c-Takayasu arteritis (c-TA) with disease duration at the time of diagnosis ≤3 months were extracted from the PRINTO database. The performance of the BVAS and DEI were examined by assessing convergent validity, the pattern of disease involvement, and responsiveness. We also evaluated alternative unweighted scoring methods for both tools. RESULTS: The analysis set included 796 patients with 669 HSP, 80 c-PAN, 25 c-WG and 22 c-TA. The median age at diagnosis was 6.9 years (6.6-12) and median delay in making the diagnosis from the onset of signs/symptoms was 0.01 (0.003-0.027) years. A strong correlation was found between the BVAS and DEI (rs=0.78) while correlation with the physician global assessment was moderate (rs=0.48) with BVAS and poor with DEI (rs=0.25). Both the BVAS and DEI sub-scores and total scores were able to descrive the disease involvement in the 4 childhood vasculitides. Responsiveness was large (>1.5) for both tools. The performance characteristics of the BVAS and DEI with the unweighted methods were comparable. CONCLUSIONS: This study demonstrates that both the BVAS and DEI are valid tools for the assessment of the level of disease activity in a large cohort of childhood acute and chronic vasculitides.


Assuntos
Indicadores Básicos de Saúde , Vasculite/diagnóstico , Criança , Diagnóstico Diferencial , Granulomatose com Poliangiite/diagnóstico , Humanos , Vasculite por IgA/diagnóstico , Poliarterite Nodosa/diagnóstico , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Arterite de Takayasu/diagnóstico , Terminologia como Assunto , Vasculite/classificação
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