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1.
J Therm Biol ; 110: 103381, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36462872

RESUMO

The global warming driven climate change has increased the susceptibility of livestock around the globe to heat stress (HS), which reduces animal productivity and threatens the sustainability of marginal farmers. The objective of this investigation was to evaluate thermo-adaptability between Tharparkar calves (TC), an indigenous milch breed of India and crossbred calves (CC) during induced heat stress in controlled environment. For this purpose, 12 apparently healthy male calves (six in each group) aged 5-6 months, were selected. The experiment was conducted at physiologically comfortable temperature (25 °C), moderate HS (31 °C) and severe HS (37 °C) for 21 days each in a psychrometric chamber. In each experimental day, the calves were exposed to 6 h of heat. There were 7 days of acclimatization period before experiment and 10 days of recovery period at ambient temperature between each 21 day exposure period. During experimental period, the blood was collected at 1st, 6th, 11th, 16th, 21st day and among ten-day recovery period the blood was collected at 5th day. Physiological responses, serum electrolytes, metabolic enzymes profiles, antioxidant capacity, oxidative stress status and general endocrine milieu were studied. Relative mRNA expression study of Heat Shock Protein (HSP) 70, HSP90, induced Nitric Oxide Synthase (iNOS) and endothelial NOS (eNOS) were carried out by qPCR. There was significant (p < 0.05) change in the displacement in rectal temperature, respiration rate, serum alanine aminotransferase level between two breeds at moderate and severe HS. Similar change was observed in total antioxidant capacity, superoxide dismutase, and endocrinological parameters. The comparatively lower mRNA expression of HSP70 and higher expression of HSP90 in TC than CC point the better thermo-adaptability of the same. The results of the experiment indicated that TC are more thermo-adaptable than CC at different modality of stress in controlled temperature conditions.


Assuntos
Antioxidantes , Ambiente Controlado , Masculino , Bovinos , Animais , Proteínas de Choque Térmico HSP70 , Temperatura , Proteínas de Choque Térmico HSP90/genética , RNA Mensageiro
2.
PLoS One ; 17(12): e0276223, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36490260

RESUMO

In ecology, an increase in genetic diversity within a community in natural ecosystems increases its productivity, while in evolutionary biology, kinship selection predicts that relatedness on social traits improves fitness. Varietal mixtures, where different genotypes are grown together, show contrasting results, especially for grain yield where both positive and negative effects of mixtures have been reported. To understand the effect of diversity on field performance, we grew 96 independent mixtures each composed with 12 durum wheat (Triticum turgidum ssp. durum Thell.) inbred lines, under two contrasting environmental conditions for water availability. Using dense genotyping, we imputed allelic frequencies and a genetic diversity index on more than 96000 loci for each mixture. We then analyzed the effect of genetic diversity on agronomic performance using a genome-wide approach. We explored the stress gradient hypothesis, which proposes that the greater the unfavourable conditions, the more beneficial the effect of diversity on mixture performance. We found that diversity on average had a negative effect on yield and its components while it was beneficial on grain weight. There was little support for the stress gradient theory. We discuss how to use genomic data to improve the assembly of varietal mixtures.


Assuntos
Ecossistema , Triticum , Triticum/genética , Locos de Características Quantitativas , Grão Comestível/genética , Variação Genética , Ambiente Controlado
3.
Sensors (Basel) ; 22(23)2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36502187

RESUMO

River floods are listed among the natural disasters that can directly influence different aspects of life, ranging from human lives, to economy, infrastructure, agriculture, etc. Organizations are investing heavily in research to find more efficient approaches to prevent them. The Artificial Intelligence of Things (AIoT) is a recent concept that combines the best of both Artificial Intelligence and Internet of Things, and has already demonstrated its capabilities in different fields. In this paper, we introduce an AIoT architecture where river flood sensors, in each region, can transmit their data via the LoRaWAN to their closest local broadcast center. The latter will relay the collected data via 4G/5G to a centralized cloud server that will analyze the data, predict the status of the rivers countrywide using an efficient Artificial Intelligence approach, and thus, help prevent eventual floods. This approach has proven its efficiency at every level. On the one hand, the LoRaWAN-based communication between sensor nodes and broadcast centers has provided a lower energy consumption and a wider range. On the other hand, the Artificial Intelligence-based data analysis has provided better river flood predictions.


Assuntos
Inteligência Artificial , Desastres , Humanos , Desastres/prevenção & controle , Inundações/prevenção & controle , Rios , Ambiente Controlado
4.
Indoor Air ; 32(11): e13163, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36437679

RESUMO

During wildfire smoke events public health agencies release advisories to stay indoors, close doors and windows, and operate a portable air cleaner (PAC). The do-it-yourself (DIY) air cleaner consisting of a box fan and a furnace filter is a widely used low-cost alternative to commercial PACs because of its increased accessibility. In this study, we evaluate the clean air delivery rate (CADR) of different DIY air cleaner designs for reducing simulated wildfire smoke and identify operating parameters that may impact their performance and use. The simplest formulation of a DIY air cleaner (box fan with taped on minimum effectiveness reporting value - [MERV] 13 furnace filter) had a CADR of 111.2 ± 1.3 ft3 /min (CFM). Increasing the fan flow by changing the fan type, increasing the fan setting, or reducing the pressure drop across the filtering surface increased the CADR. Large increases in CADR could be obtained by using a shroud (40%), using a 4″ thick filter (123%) using two filters in a wedge shape (137%), or using four filters in a Corsi-Rosenthal (CR) box design (261%). The CADR was greatly reduced with filters heavily loaded with smoke, pointing to the need for frequent filter changes during smoke events.


Assuntos
Poluição do Ar em Ambientes Fechados , Incêndios Florestais , Fumaça/análise , Poluição do Ar em Ambientes Fechados/análise , Ambiente Controlado , Habitação
5.
Front Public Health ; 10: 962478, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36211705

RESUMO

Objectives: During COVID-19 the re-opening of educational institutes was frequently debated, however with the decline in the number of COVID-19 cases, The Aga Khan University (AKU) in Karachi, Pakistan opened its campus for medical and nursing students after more than 6 months of closure. To ensure gradual resumption of activities on-campus, a combination of interventions was diligently deployed to minimize student infection rates. Scarce literature exists on students' perceptions regarding decisions implemented by university leadership. The aim of the study was to determine the efficacy of these interventions. Methods: We conducted a convergent, parallel, mixed-methods observational study targeting medical and nursing students. An online questionnaire was disseminated to elicit students' degree of (dis)agreement on a four-point Likert scale. Focused group discussions (FGDs) were conducted to comprehend reasons for (dis)agreement. Results: Total of 183 students responded to questionnaire (59.0% nursing, 67.8% female), 11 FGDs were conducted with 85 students. Interventions with highest agreement were mandatory face masks policy (94.54%), weekly mandated COVID-testing (92.35%) and students' Academic Bubble (91.26%); highest disagreement was for Sehat Check application (41.53%); and stay strong campaign (40.44%). Four themes emerged from FGDs: Effective safety interventions, Safety interventions with limited effectiveness, Utility of Sehat Check Application and Future recommendations for informing policy. Conclusion: It is paramount to seek student-feedback at forefront of university re-opening strategy. Clear communication channels are as important as an administrative response system's robustness. Bidirectional communication channels are fundamental and requisite during ever-changing policies and regulations. Engaging student representatives in decision making or implementation processes (such as "pilot" before "roll-out") would allow any potential issues to be managed early on. Gather real-time anonymous feedback and identify key areas that need further promulgation and those that need to be replaced with more effective ones.


Assuntos
COVID-19 , Estudantes de Enfermagem , COVID-19/epidemiologia , COVID-19/prevenção & controle , Ambiente Controlado , Feminino , Grupos Focais , Humanos , Masculino , Universidades
6.
Sensors (Basel) ; 22(20)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36298316

RESUMO

Controlled environment agriculture (CEA) is an unconventional production system that is resource efficient, uses less space, and produces higher yields. Deep learning (DL) has recently been introduced in CEA for different applications including crop monitoring, detecting biotic and abiotic stresses, irrigation, microclimate prediction, energy efficient controls, and crop growth prediction. However, no review study assess DL's state of the art to solve diverse problems in CEA. To fill this gap, we systematically reviewed DL methods applied to CEA. The review framework was established by following a series of inclusion and exclusion criteria. After extensive screening, we reviewed a total of 72 studies to extract the useful information. The key contributions of this article are the following: an overview of DL applications in different CEA facilities, including greenhouse, plant factory, and vertical farm, is presented. We found that majority of the studies are focused on DL applications in greenhouses (82%), with the primary application as yield estimation (31%) and growth monitoring (21%). We also analyzed commonly used DL models, evaluation parameters, and optimizers in CEA production. From the analysis, we found that convolutional neural network (CNN) is the most widely used DL model (79%), Adaptive Moment Estimation (Adam) is the widely used optimizer (53%), and accuracy is the widely used evaluation parameter (21%). Interestingly, all studies focused on DL for the microclimate of CEA used RMSE as a model evaluation parameter. In the end, we also discussed the current challenges and future research directions in this domain.


Assuntos
Aprendizado Profundo , Redes Neurais de Computação , Agricultura , Ambiente Controlado
7.
Int J Pharm Compd ; 26(5): 411-418, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36053768

RESUMO

Compounded sterile preparations are required to be at the very least sterile. If not, the parenteral administration of such a preparation can cause serious patient harm, even death. Therefore, cleanroom contamination control strategies must be employed to protect the final preparation and the patient. This article is part one of a two-part series describing a holistic and multi-faceted approach to implementing basic cleanroom contamination control strategies at sterile compounding facilities so that safer pharmaceutical compounds are produced. This segment uncovers where cleanroom contamination comes from, the costs and implications associated with cleanroom contamination, and focuses on the various facility controls required to prevent the ingress of contaminants and cross-contamination. The second part concentrates on personnel and processes that support the same initiative.


Assuntos
Contaminação de Medicamentos , Dano ao Paciente , Composição de Medicamentos , Contaminação de Medicamentos/prevenção & controle , Ambiente Controlado , Humanos , Preparações Farmacêuticas
8.
J Healthc Eng ; 2022: 8749785, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35991295

RESUMO

Background: Indoor air quality is controlled in the clean operating room (OR) to reduce the risk of surgical-site infections (SSIs). The aim of this study is to assess the usage and management of clean ORs in China and to identify factors associated with the risk of SSIs. Methods: An online survey was distributed to hospitals in China from August 5 to September 5, 2018 via the WeChat account of the Shanghai International Forum for Infection Control and Prevention. The questionnaire consisted of two parts: basic information (hospital type, level, and number of beds) and usage and management (number of ORs, usage time, maintenance mode, test frequency, compliance with current standards, and comfort of healthcare workers). The significance of factors associated with the cleanliness and maintenance of clean ORs was assessed by univariate and multivariate logistic regression analyses. Results: Among 1,308 responding hospitals, 25.7% failed to comply with current standards. "Maintenance mode" had a significant effect on compliance with current standards for clean ORs (p < 0.0001) and "professional" maintenance was superior to "outsource or no" maintenance (odds ratio = 0.511, 95% confidence interval = 0.367-0.711). There was a significant difference in the comfort of healthcare workers in clean ORs that complied with current standards vs. those that did not (39.92% [388/972] vs. 64.28% [216/336], respectively, p < 0.0001). Humidity was the chief complaint among healthcare workers. Conclusion: Maintenance of clean ORs was significantly associated with the compliance of current standards. Noncompliance with current standards was associated with greater risks of SSIs. Maintenance of ORs for prevention of SSIs should consider the costs and benefits.


Assuntos
Hospitais , Salas Cirúrgicas , China , Ambiente Controlado , Humanos , Infecção da Ferida Cirúrgica/prevenção & controle , Inquéritos e Questionários
9.
Life Sci Space Res (Amst) ; 34: 37-44, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35940688

RESUMO

Future space missions will likely include plants to provide fresh foods and bioregenerative life support capabilities. Current spacecraft such as the International Space Station (ISS) operate at 1 atm (101 kPa) pressure, but future missions will likely use reduced pressures to minimize gas leakage and facilitate rapid egress (space walks). Plants for these missions must be able to tolerate and grow reliably at these reduced pressures. We grew two lettuce cultivars, 'Flandria' a green bibb-type and 'Outredgeous,' a red, loose-leaf type, under three pressures: 96 kPa (ambient control), 67 kPa (2/3 atm), and 33 kPa (1/3 atm) for 21 days in rockwool using recirculating nutrient film technique hydroponics. Each treatment was repeated three times using a different hypobaric chamber each time. A daily light integral of 17.2 Moles Photosynthetically Active Radiation per day was provided with metal halide lamps set to deliver 300 µmol m-2s -1 photosynthetic photon flux (PPF) for a 16 h photoperiod at 22 °C. Oxygen was maintained at 21 kPa (equal to 21% at 1 atm) and CO2 at 0.12 kPa (equal to 1200 ppm at 1 atm). Leaf area for 'Outredgeous' was reduced 20% and 38% at 67 kPa and 33 kPa respectively; shoot fresh mass was reduced 22% and 41% at 67 kPa and 33 kPa respectively when compared to control plants at 96 kPa. These trends were not statistically significant at P ≥ 0.05. Leaf area for 'Flandria' showed no difference between 96 and 67 kPa but was reduced 31% at 33 kPa; shoot fresh mass was reduced 6% and 27% at 66 kPa and 33 kPa respectively compared to 96 kPa. There were 10% and 25% increases in anthocyanin concentration at 66 kPa and 33 kPa compared to 96 kPa, potentially increasing the bioprotective capacity of the plant. Previous studies with other cultivars of lettuce showed slight change in growth across this range of pressures, suggesting responses may vary among genotypes, hypobaric exposure treatments, and / or environmental conditions. Collectively, the findings suggest further testing is needed to understand the effects of atmospheric pressure on plant growth.


Assuntos
Ambiente Controlado , Alface , Pressão Atmosférica , Dióxido de Carbono , Fotossíntese , Folhas de Planta
10.
Methods Mol Biol ; 2539: 57-68, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35895196

RESUMO

It is essential that the scientific community develop and deploy accurate and high-throughput techniques to capture factors that influence plant phenotypes if we are to meet the projected demands for food and energy. In recognition of this fact, multiple research institutions have invested in automated high-throughput plant phenotyping (HTPP) systems designed for use in controlled environments. These systems can generate large amounts of data in relatively short periods of time, potentially allowing researchers to gain insights about phenotypic responses to environmental, biological, and management factors. Reliable inferences about these factors depends on the use of proper experimental design when planning phenotypic studies in order to avoid issues such as lack of power and confounding. In this chapter, the topic of experimental design will be discussed, from basic principles to examples specific to controlled environment plant phenotyping. Examples will be provided based on the package agricolae in the R statistical language.


Assuntos
Plantas , Projetos de Pesquisa , Ambiente Controlado , Fenótipo , Plantas/genética
11.
Artigo em Inglês | MEDLINE | ID: mdl-35665645

RESUMO

Carcinoid tumors referred to neuroendocrine neoplasms that often are indolent and may not became clinical apparent until there has been metastatic spread. Urinary 5-hydroxyindoleacetic acid (5-HIAA) was recommended as a first-line screening biomarker for the diagnosis and follow-up of carcinoid tumors. The measurement of this analyte is conventionally performed by spectrophotometer or high performance liquid chromatography, and has switched to liquid chromatography-tandem mass spectrometry (LC-MS/MS) recently. In this study, a fast, simple and reliable LC-MS/MS method has been developed and validated for 24 h urinary 5-HIAA determination and the quality assurance referring to post-implementation monitoring has been explored. 50 µL of urine was mixed with 200 µL of a 50% methanol/water solution containing the internal standard 5-HIAA-d5. The mixture was centrifuged and the supernatant was used for direct analysis by LC-MS/MS. The retention time of 5-HIAA is 2.37 min and a total run time is 4 min. This method was validated for excellent linearity from 0.675 to 43.3 µM with CVs ≤ 6.64% and good recovery in the range of 87.1%-107%. No obvious matrix effect was observed. Intra- and inter-day imprecision were below 3.95% and 4.66% respectively. The reference interval of 24-hour urinary 5-HIAA in Chinese adults was established. The quality assurance could ensure reliable and comparable results in routine clinical testing. Thus, this fast, simple and reliable LC-MS/MS method could be proposed as a tool for clinical testing of urinary 5-HIAA in quality-controlled environments.


Assuntos
Tumor Carcinoide , Espectrometria de Massas em Tandem , Adulto , Tumor Carcinoide/diagnóstico , Cromatografia Líquida/métodos , Ambiente Controlado , Humanos , Ácido Hidroxi-Indolacético , Padrões de Referência , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
12.
Artigo em Inglês | MEDLINE | ID: mdl-35760269

RESUMO

Digestive morphology and physiology differ across animal species, with many comparative studies uncovering relationships between animal ecology or diet, and the morphology and physiology of the gastrointestinal tract. However, many of these studies compare wild-caught animals feeding on uncontrolled diets and compare broadly related taxa. Thus, few studies have disentangled the phenotypic consequences of genetics from those potentially caused by the environment, especially across closely related species that occupy similar ecological niches. Here, we examined differences in digestive morphology and physiology of five closely related species of Peromyscus mice that were captive bred under identical environmental conditions and identical diets for multiple generations. Using phylogenetic generalized least squares (PGLS) of species means to control for body size, we identified a phylogenetic signal in the mass of the foregut and length of the small intestine across species. As proportions of total gut mass, we identified phylogenetic signals in relative foregut and small intestine masses, indicating that the sizes of these structures are more similar among closely related species. Finally, we detected differences in activities of the protease aminopeptidase-N enzyme across species. Overall, we demonstrate fine-scale differences in digestive morphology and physiology among closely related species. Our results suggest that Peromyscus could provide a system for future studies to explore the interplay between natural history, morphology, and physiology (e.g. ecomorphology and ecophysiology), and to investigate the genetic architecture that underlies gut anatomy.


Assuntos
Dieta , Peromyscus , Animais , Ambiente Controlado , Trato Gastrointestinal/fisiologia , Filogenia
13.
Artif Organs ; 46(9): 1760-1770, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35403254

RESUMO

BACKGROUND: Human bone marrow mesenchymal stem cells (hMSCs) present a promising cell source with the potential to be used for curing various intractable diseases, and it is expected that the development of regenerative medicine employing cell-based therapy would be significantly accelerated when such methods are established. For that, powerful methods for selective growth and differentiation of hMSCs should be developed. METHODS: We developed an efficient method for hMSC proliferation and differentiation into osteoblasts and adipocytes using gravity-controlled environments. RESULTS: The results indicate that the average doubling time of hMSCs cultured in a regular maintenance medium under microgravity conditions (0.001 G) was 1.5 times shorter than that of cells cultured under natural gravity conditions (1.0 G). Furthermore, 99.2% of cells grown in the microgravity environment showed the expression of hMSC markers, as indicated by flow cytometry analysis. Osteogenic and adipogenic differentiation of hMSCs expanded in the microgravity environment was enhanced under microgravity and hypergravity conditions, respectively, as evidenced by the downregulation of hMSC markers and upregulation of osteoblast and adipocyte markers, respectively. Most cells differentiated into osteoblasts in the microgravity environment after 14 days (~80%) and adipocytes in the hypergravity environment after 12 days (~90%). CONCLUSIONS: Our results indicate that hMSC proliferation and selective differentiation into specific cell lineages could be promoted under microgravity or hypergravity conditions, suggesting that cell culture in the gravity-controlled environment is a useful method to obtain cell preparations for potential clinical applications.


Assuntos
Células-Tronco Mesenquimais , Diferenciação Celular/fisiologia , Proliferação de Células , Células Cultivadas , Ambiente Controlado , Humanos , Osteoblastos , Osteogênese
14.
Sensors (Basel) ; 22(7)2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35408410

RESUMO

Despite their enormous potential, the use of indoor localization systems (ILS) remains seldom. One reason is the lack of market transparency and stakeholders' trust in the systems' performance as a consequence of insufficient use of test and evaluation (T&E) methodologies. The heterogeneous nature of ILS, their influences, and their applications pose various challenges for the design of a methodology that provides meaningful results. Methodologies for building-wide testing exist, but their use is mostly limited to associated indoor localization competitions. In this work, the T&E 4iLoc Framework is proposed-a methodology for T&E of indoor localization systems in semi-controlled environments based on a system-level and black-box approach. In contrast to building-wide testing, T&E in semi-controlled environments, such as test halls, is characterized by lower costs, higher reproducibility, and better comparability of the results. The limitation of low transferability to real-world applications is addressed by an application-driven design approach. The empirical validation of the T&E 4iLoc Framework, based on the examination of a contour-based light detection and ranging (LiDAR) ILS, an ultra wideband ILS, and a camera-based ILS for the application of automated guided vehicles in warehouse operation, demonstrates the benefits of T&E with the T&E 4iLoc Framework.


Assuntos
Ambiente Controlado , Confiança , Coleta de Dados , Reprodutibilidade dos Testes
15.
Int J Mol Sci ; 23(7)2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35408899

RESUMO

Plant disease and insect pests are major limiting factors that reduce crop production worldwide. The ornamental indoor cultivation cash crop dwarf coffee Punica arabica 'Pacas' is also troubled by these issues. Silicon (Si) is one of the most abundant elements in the lithosphere and positively impacts plant health by effectively mitigating biotic and abiotic stresses. Several studies have shown that Si activates plant defense systems, although the specific nature of the involvement of Si in biochemical processes that lead to resistance is unclear. In our study, Si significantly promoted the growth and development of dwarf coffee seedlings grown in plant growth chambers. More than that, through natural infection, Si suppressed disease and insect pests by improving physiology (e.g., the strong development of the internal structures of roots, stems, and leaves; higher photosynthetic efficiency; more abundant organic matter accumulation; the promotion of root activity; the efficient absorption and transfer of mineral elements; and various activated enzymes) and up-regulating defense genes (CaERFTF11 and CaERF13). Overall, in agriculture, Si may potentially contribute to global food security and safety by assisting in the creation of enhanced crop types with optimal production as well by mitigating plant disease and insect pests. In this sense, Si is a sustainable alternative in agricultural production.


Assuntos
Coffea , Silício , Animais , Café , Ambiente Controlado , Insetos , Plantas , Silício/farmacologia
16.
Plant Dis ; 106(8): 2060-2065, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35285255

RESUMO

Calonectria ilicicola is a soilborne fungus responsible for red crown rot (RCR) in soybeans. Recently, this disease has been detected in new areas within the United States and Asia, where it has been reported to cause significant yield losses. To date, no data on the efficacy of fungicide seed treatments for suppressing RCR in soybeans are available. We screened three commercially available soybean seed treatments (Acceleron STANDARD; Acceleron STANDARD + IleVO; Cruiser MAXX + Saltro) for impacts on germination, seedling growth, and disease caused by C. ilicicola under controlled laboratory conditions. The Cruiser MAXX + Saltro treatment improved final plant dry mass to levels similar to noninoculated controls. Both Acceleron STANDARD + IleVO and Cruiser MAXX + Saltro reduced percent root rot. Acceleron STANDARD alone did not impact root rot, indicating that the IleVO component was efficacious on C. ilicicola. These data indicate that IleVO and Cruiser MAXX + Saltro have potential for reducing early season impacts of RCR in soybeans. Future work assessing these seed treatments in field-grown soybeans is needed to better understand the role of seed treatments as components of an integrated management program for RCR.


Assuntos
Doenças das Plantas , Soja , Ambiente Controlado , Germinação , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Sementes , Soja/microbiologia , Estados Unidos
17.
J Occup Environ Hyg ; 19(4): 210-222, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35143378

RESUMO

Exposures to vapors generated by small spills of organic solvents are common in the occupational hygiene practice. In these scenarios, contaminant mass release is exponentially decreasing, driven by an evaporation rate constant alpha (α). Knowing α is fundamental for adequately modeling peak concentrations and/or short-term exposures that occur and for achieving efficient occupational risk analysis and management. The purpose of this study was to measure alpha experimentally using a gravimetric approach in a controlled environment during solvent evaporation tests designed to simulate small spills of solvents. The effects of several factors on α were evaluated. Equations based on regression models derived from the experimental data were proposed for predicting α. Predictions were externally validated against experimental data. A total of 183 tests was performed. Data analyses found that alpha (α) values increased with vapor pressure, spill surface area-to-spill volume ratio, and air speed across the spill. Larger α were associated with petri dish containers compared to watch glasses. Three regression models were created for predicting α. They had four variables in common, namely vapor pressure, molecular weight, air speed above the liquid, and surface tension of the liquid. The fifth variable was either spill volume, spill surface area, or spill surface area-to-spill volume ratio. The R2 of the regression models were equal to 0.98. External validation showed mean relative errors of -32.9, -32.0, and -25.5%, respectively, with associated standard deviations of the relative errors of 17.7, 33.3, and 26.0%, respectively, and associated R2 of 0.92, 0.65, and 0.87, respectively. The proposed equations can be used for estimating α in exposure scenarios similar to those evaluated in this study. Moreover, these models constitute a step further in the improvement of knowledge on estimating evaporation rates for small spills of organic solvents.


Assuntos
Ambiente Controlado , Modelos Teóricos , Fenômenos Físicos , Medição de Risco , Solventes/análise
18.
Sensors (Basel) ; 22(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35161555

RESUMO

Wireless sensing is the utmost cutting-edge way of monitoring different health-related activities and, concurrently, preserving most of the privacy of individuals. To meet future needs, multi-subject activity monitoring is in demand, whether it is for smart care centres or homes. In this paper, a smart monitoring system for different human activities is proposed based on radio-frequency sensing integrated with ensemble machine learning models. The ensemble technique can recognise a wide range of activity based on alterations in the wireless signal's Channel State Information (CSI). The proposed system operates at 3.75 GHz, and up to four subjects participated in the experimental study in order to acquire data on sixteen distinct daily living activities: sitting, standing, and walking. The proposed methodology merges subject count and performed activities, resulting in occupancy count and activity performed being recognised at the same time. To capture alterations owing to concurrent multi-subject motions, the CSI amplitudes collected from 51 subcarriers of the wireless signals were processed and merged. To distinguish multi-subject activity, a machine learning model based on an ensemble learning technique was designed and trained using the acquired CSI data. For maximum activity classes, the proposed approach attained a high average accuracy of up to 98%. The presented system has the ability to fulfil prospective health activity monitoring demands and is a viable solution towards well-being tracking.


Assuntos
Software , Caminhada , Ambiente Controlado , Atividades Humanas , Humanos , Estudos Prospectivos
19.
PDA J Pharm Sci Technol ; 76(2): 109-119, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34131012

RESUMO

In cleanroom facilities, both disposable and reusable textile garments (coveralls, boots, hoods, and frocks) meet the particulate standards from the most rigorous to the most basic levels. However, the reusables clearly offer two other important benefits, lower annual cost and lower environmental impact. The objectives of this article are to now provide quantitative reusable product benefits on a U.S. national environmental and economic basis. This is the first quantitative, novel multi-user economic evaluation of selecting cleanroom reusables over disposables. For personal protection equipment (PPE), these cost and environmental benefits indicate there is also an improved environmental and economic aspect to the increased national demand for reusables related to coronavirus disease 2019 (COVID-19), while necessary cleaning with approved detergents is easily achieved. The current reusable cleanroom market (14.1 million packages) was estimated to be 60% nonsterile and 40% sterilized. The total market is about 50% reusable and 50% disposable. This research documents that there is an annual cost reduction of about 58% when selecting reusables over disposables, giving an economic savings to the U.S. cleanroom sector from reusables of about $1.2 billion in the next decade. This is also saving the total U.S. about 136 million MJ natural resource energy/year (38 million kWh) and about 8.4 million kg CO2eq annually (removal of about 1,650 cars/year). A maximum hypothetical case for reusables at 87.5% of the market (12.5% are mandatory Hazmat disposable) would yield a U.S. national savings of nearly $2.1 billion/decade to the cleanroom sector bottom line, as well as 2.4 billion MJ nre savings in energy or removal of about 29,000 cars/decade. These results indicate there are effective, verifiable, and easily obtained environmental and economic benefits by the basic transition by diverse cleanrooms in deciding to select reusable garments.


Assuntos
COVID-19 , Equipamentos Descartáveis , COVID-19/prevenção & controle , Análise Custo-Benefício , Ambiente Controlado , Humanos , Têxteis
20.
Artigo em Inglês | MEDLINE | ID: mdl-34509593

RESUMO

There is increased interest in rearing salmon in Recirculating Aquaculture Systems (RAS), where environmental conditions can be tightly controlled to optimize growth. Photoperiod and salinity are two important parameters that can be manipulated in RAS. A longer photoperiod permits more time for feeding, while intermediate salinities may reduce the energetic costs of ionoregulation, both of which may enhance growth. However, little is known about how rearing at different photoperiods and salinity affect behaviour, an understudied but important research topic for intensive fish rearing. To address this, we examined the behavioural effects of two salinities and two photoperiod regimes in coho salmon (Oncorhynchus kisutch) post-smolts reared continuously for 120 days in a RAS. Fish were reared on a photoperiod of either 12 h light:12 h dark (12:12), or 24 h light (24:0) at salinities of 2.5 and 10 ppt. To investigate behavioural differences associated with these treatments, we quantified: i) movement in an open-field test, ii) exploratory behaviour/boldness using a novel object approach test, and iii) anxiety-like behaviour with a light/dark test. The 24:0 groups displayed no differences in boldness/anxiety-like behaviour and locomotion relative to the 12:12 groups at their respective salinities. Taken together, fish reared under continuous light (24:0) show negligible behavioural alterations compared to fish reared under normal light dark conditions (12:12).


Assuntos
Aquicultura/métodos , Oncorhynchus kisutch/fisiologia , Fotoperíodo , Animais , Ansiedade , Aquicultura/instrumentação , Comportamento Animal , Ambiente Controlado , Locomoção , Oncorhynchus kisutch/crescimento & desenvolvimento , Salinidade
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