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1.
ACS Sens ; 5(2): 571-579, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32013398

RESUMO

During the detection of industrial toxic gases, such as triethylamine (TEA), poor selectivity and negative humidity impact are still challenging issues. A frequently reported strategy is to employ molecular sieves or metal-organic framework (MOF) membranes so that interference derived from surrounding gases or water vapor can be blocked. Nevertheless, the decline in the response signal was also observed after coating these membranes. Herein, an alternative strategy that is based on a hydrophobic, TEA adsorption-selective p-n conjunction core-shell heterostructure is proposed and is speculated to simultaneously enhance selectivity, sensitivity, and humidity resistance. To verify the practicability of the proposed strategy, a thickness-tunable nitrogen-doped carbon (N-C) shell-coated α-Fe2O3 nano-olive (N-C@α-Fe2O3 NO)-based core-shell heterostructure that is obtained via a unique all-vapor-phase processing method is selected as the research example. After forming the core-shell heterostructure, a relatively hydrophobic and TEA adsorption-selective N-C@α-Fe2O3 NO surface was experimentally confirmed. Particularly, a chemiresistive sensor that comprises N-C@α-Fe2O3 NOs exhibits satisfactory selectivity and response magnitude to TEA when compared with the sensor using α-Fe2O3 NOs. The detection limit can even reduce to be 400 ppb at 250 °C. Furthermore, the sensor based on N-C@α-Fe2O3 NOs shows desirable humidity resistance within the relative humidity (RH) range of 30-90%. For practical usage, a sensing prototype based on the N-C@α-Fe2O3 NO probe is fabricated, and its satisfactory sensing performance further confirms the potential for future applications in industrial organic amine detection. These promising results show a bright future in enhancing the humidity resistance and selectivity as well as sensitivity of chemiresistive sensors by simply designing a hydrophobic and target gas adsorption (e.g., TEA) preferred p-n junction core-shell heterostructure.


Assuntos
Etilaminas/química , Umidade/normas , Interações Hidrofóbicas e Hidrofílicas , Adsorção
2.
Artigo em Inglês | MEDLINE | ID: mdl-31717831

RESUMO

This paper emphasizes the importance of environmental protection regarding the reduction of energy consumption while maintaining living standards. The aim of the research is to observe the effects of mechanical and natural ventilation on energy consumption and building operation as well as indoor environmental quality (IEQ). The results of indoor environmental quality testing show that the mean relative humidity (31%) is in the permissible range (30%-70%); the mean CO2 concentration (1050.5 ppm) is above the recommended value of 1000 ppm according to Pettenkofer; and the mean PM10 concentration (43.5 µg/m3) is under the limit value of 50 µg/m3. A very large positive correlation is found between relative humidity and concentration of CO2 as well as between the concentration of PM5 and the concentration of CO2. The most commonly occurring sick building syndrome (SBS) symptoms are found to be fatigue and the feeling of a heavy head.


Assuntos
Poluição do Ar em Ambientes Fechados/prevenção & controle , Umidade/normas , Ventilação , Ar Condicionado , Dióxido de Carbono , Humanos , Material Particulado , Fenômenos Físicos
3.
J Assist Reprod Genet ; 36(8): 1571-1577, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31267335

RESUMO

PURPOSE: To investigate the stability of osmolality in non-humidified and humidified incubators for assisted reproductive technologies (ART). METHODS: Drops of three single-step culture media (media A, B, and C) were incubated for 5 or 6 days covered with four different mineral oils (oils A, B, C, and D) in non-humidified incubator A, non-humidified incubator B, or humidified incubator C to investigate the effects of incubator environment (humidification), drop volume, culture media, and mineral oil on the stability of osmolality in microdrops. RESULTS: A significant and linear increase was shown in the osmolality of 50-µL and 200-µL microdrops covered with mineral oil during 5 days incubation in non-humidified benchtop incubators. The maximum increase was 20 mOsm/kg, and the extent of the increase was affected by microdrop volume and possibly by the type of mineral oil used to cover the drops. In contrast, the osmolality of 50-µL and 200-µL microdrops did not change during 5 days incubation in a humidified benchtop incubator. CONCLUSIONS: Mineral oil alone may not adequately prevent gradual changes in the osmolality of low-volume microdrops during extended in vitro culture of human embryos in non-humidified incubators. As a result, the osmolality may increase to high enough levels to stress some human embryos and adversely affect clinical outcomes. We therefore recommend that the stability of osmolality should be given more consideration to ensure optimal culture conditions for ART.


Assuntos
Técnicas de Cultura Embrionária/instrumentação , Embrião de Mamíferos/citologia , Fertilização in vitro/normas , Umidade/normas , Incubadoras/normas , Meios de Cultura , Técnicas de Cultura Embrionária/métodos , Técnicas de Cultura Embrionária/normas , Desenvolvimento Embrionário , Feminino , Humanos , Óleo Mineral , Concentração Osmolar
4.
Respir Care ; 64(7): 809-817, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30837330

RESUMO

BACKGROUND: High-flow nasal cannula (HFNC) therapy is used for patients with respiratory failure. Recently, HFNC therapy with very high gas flows (ie, gas flows of 60-100 L/min) was reported to generate higher positive airway pressure and an associated decrease in breathing frequency. However, the humidification of HFNC therapy with very high gas flow remains to be clarified. METHODS: We evaluated 3 heated humidifier systems: a single MR850, the Hummax2, and parallel MR850s. The MR850 is a pass-over humidifier system, and the Hummax2 works with a porous hollow polyethylene fiber membrane. The parallel MR850 system included 2 MR850s connected in parallel to the lung with a 22 mm Y-piece. Gas flow was set at 40-90 L/min in increments of 10 L/min, and FIO2 was set at 0.21. Heated humidifiers in the MR850 systems were set in invasive mode (40°C/-3), and with the Hummax2 the vapor temperature was set at 39°C. The simulated external nares were connected to a test lung via a standard ventilator circuit. One-way valves prevented mixing of inspired and expired gases. Compliance of the test lung was 0.05 L/cm H2O and resistance 5 cm H2O/L/s. Simulated tidal volumes (VT) were 300, 500, and 700 mL, with a breathing frequency of 10 or 20 breaths/min and an inspiratory time of 1.0 s. Temperature, relative humidity, and absolute humidity (AH) of inspired gas downstream of the external nares were measured using a hygrometer for 1 min, and results for the last 3 breaths were extracted. RESULTS: With the single MR850, when gas flow was > 80 L/min, AH decreased as gas flow increased (P < .001). With the Hummax2, as gas flow increased, AH decreased (P < .001). With the parallel MR850s, regardless of gas flow, AH was constant. As breathing frequency increased, AH increased in all systems. CONCLUSIONS: During HFNC therapy with very high gas flows in this bench study, conventional heated humidifiers did not provide adequate humidification. Caution is advised when using HFNC therapy with very high gas flows with conventional heated humidifiers.


Assuntos
Calefação , Umidificadores/normas , Oxigenoterapia/instrumentação , Insuficiência Respiratória/terapia , Cateterismo/métodos , Simulação por Computador , Desenho de Equipamento , Calefação/métodos , Calefação/normas , Humanos , Umidade/normas , Teste de Materiais/métodos , Oxigenoterapia/efeitos adversos , Oxigenoterapia/métodos
5.
Adv Neonatal Care ; 18(5): 366-377, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29933338

RESUMO

BACKGROUND: Approximately half of the 55,000 very low birth-weight infants (<1500 g) born in the United States each year develop bronchopulmonary dysplasia (BPD). Many etiologies have been associated with the development of BPD, including aberrant temperature/humidity levels of artificial ventilation. PURPOSE: The purpose of this literature review is to explore what is known regarding inspired air temperature/humidity levels from artificial ventilation in very premature infants, focusing on what levels these infants actually receive, and what factors impact these levels. METHODS/SEARCH STRATEGY: PubMed, CINAHL, Scopus, and Web of Science were searched. Of the 830 articles retrieved, 23 were synthesized for study purpose, sample/study design, and temperature/humidity findings. FINDINGS/RESULTS: Heating and humidification practices studied in neonatal ventilation did not maintain recommended levels. In addition, human neonatal studies and noninvasive neonatal ventilation research were limited. Furthermore, ventilation settings, environmental temperatures, and mouth position (in noninvasive ventilation) were found to impact temperature/humidity levels. IMPLICATIONS FOR PRACTICE: Environmental temperatures and ventilatory settings merit consideration during artificial ventilation. In addition, aberrant temperature/humidity levels may impact infant body temperature stability; thus, employing measures to ensure adequate thermoregulation while receiving artificial ventilation must be a priority. IMPLICATIONS FOR RESEARCH: This review underscores the need for further research into current warming and humidification techniques for invasive and noninvasive neonatal ventilation. A focus on human studies and the impact of aberrant levels on infant body temperature are needed. Future research may provide management options for achieving and maintaining target temperature/humidity parameters, thus preventing the aberrant levels associated with BPD.


Assuntos
Displasia Broncopulmonar/terapia , Temperatura Alta/uso terapêutico , Umidade , Respiração Artificial/métodos , Respiração Artificial/normas , Ventiladores Mecânicos/normas , Humanos , Umidade/normas , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido de muito Baixo Peso , Ventilação não Invasiva/métodos , Temperatura
7.
Artigo em Inglês | MEDLINE | ID: mdl-28934173

RESUMO

Existing thermal comfort field studies are mainly focused on the relationship between the indoor physical environment and the thermal comfort. In numerous chamber experiments, physiological parameters were adopted to assess thermal comfort, but the experiments' conclusions may not represent a realistic thermal environment due to the highly controlled thermal environment and few occupants. This paper focuses on determining the relationships between upper extremity skin temperatures (i.e., finger, wrist, hand and forearm) and the indoor thermal comfort. Also, the applicability of predicting thermal comfort by using upper extremity skin temperatures was explored. Field studies were performed in office buildings equipped with split air-conditioning (SAC) located in the hot summer and cold winter (HSCW) climate zone of China during the summer of 2016. Psychological responses of occupants were recorded and physical and physiological factors were measured simultaneously. Standard effective temperature (SET*) was used to incorporate the effect of humidity and air velocity on thermal comfort. The results indicate that upper extremity skin temperatures are good indicators for predicting thermal sensation, and could be used to assess the thermal comfort in terms of physiological mechanism. In addition, the neutral temperature was 24.7 °C and the upper limit for 80% acceptability was 28.2 °C in SET*.


Assuntos
Ar Condicionado/normas , Umidade/normas , Temperatura Cutânea/fisiologia , Temperatura , Extremidade Superior/fisiologia , Adulto , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Eur J Anaesthesiol ; 34(8): 515-525, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28403017

RESUMO

BACKGROUND: The minimum inhaled gas absolute humidity level is 20 mgH2O l for short-duration use in general anaesthesia and 30 mgH2O l for long-duration use in intensive care to avoid respiratory tract dehydration. OBJECTIVE: The aim is to compare the effects of different fresh gas flows (FGFs) through a circle rebreathing system with or without a heat and moisture exchanger (HME) on inhaled gas absolute humidity in adults undergoing general anaesthesia. DESIGN: Systematic review and meta-analyses of randomised controlled trials. We defined FGF (l min) as minimal (0.25 to 0.5), low (0.6 to 1.0) or high (≥2). We extracted the inhaled gas absolute humidity data at 60 and 120 min after connection of the patient to the breathing circuit. The effect size is expressed as the mean differences and corresponding 95% confidence intervals (CI). DATA SOURCES: PubMed, EMBASE, SciELO, LILACS and CENTRAL until January 2017. RESULTS: We included 10 studies. The inhaled gas absolute humidity was higher with minimal flow compared with low flow at 120 min [mean differences 2.51 (95%CI: 0.32 to 4.70); P = 0.02] but not at 60 min [mean differences 2.95 (95%CI: -0.95 to 6.84); P = 0.14], and higher with low flow compared with high flow at 120 min [mean differences 7.19 (95%CI: 4.53 to 9.86); P < 0.001]. An inhaled gas absolute humidity minimum of 20 mgH2O l was attained with minimal flow at all times but not with low or high flows. An HME increased the inhaled gas absolute humidity: with minimal flow at 120 min [mean differences 8.49 (95%CI: 1.15 to 15.84); P = 0.02]; with low flow at 60 min [mean differences 9.87 (95%CI: 3.18 to 16.57); P = 0.04] and 120 min [mean differences 7.19 (95%CI: 3.29 to 11.10); P = 0.003]; and with high flow of 2 l min at 60 min [mean differences 6.46 (95%CI: 4.05 to 8.86); P < 0.001] and of 3 l min at 120 min [mean differences 12.18 (95%CI: 6.89 to 17.47); P < 0.001]. The inhaled gas absolute humidity data attained or were near 30 mgH2O l when an HME was used at all FGFs and times. CONCLUSION: All intubated patients should receive a HME with low or high flows. With minimal flow, a HME adds cost and is not needed to achieve an appropriate inhaled gas absolute humidity.


Assuntos
Anestesia com Circuito Fechado/métodos , Anestesia Geral/métodos , Anestésicos Inalatórios/administração & dosagem , Temperatura Alta , Umidade , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Administração por Inalação , Anestesia com Circuito Fechado/instrumentação , Anestesia Geral/instrumentação , Temperatura Alta/uso terapêutico , Humanos , Umidade/normas , Resultado do Tratamento
9.
Anesth Analg ; 125(4): 1214-1218, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-27669553

RESUMO

There is a direct relationship between the quality of the environment of a workplace and the productivity and efficiency of the work accomplished. Components such as temperature, humidity, ventilation, drafts, lighting, and noise each contribute to the quality of the overall environment and the sense of well-being of those who work there.The modern operating room is a unique workplace with specific, and frequently conflicting, environmental requirements for each of the inhabitants. Even minor disturbances in the internal environment of the operating room can have serious ramifications on the comfort, effectiveness, and safety of each of the inhabitants. A cool, well-ventilated, and dry climate is optimal for many members of the surgical team. Any significant deviation from these objectives raises the risk of decreased efficiency and productivity and adverse surgical outcomes. A warmer, more humid, and quieter environment is necessary for the patient. If these requirements are not met, the risk of surgical morbidity and mortality is increased. An important task for the surgical team is to find the correct balance between these 2 opposed requirements. Several of the components of the operating room environment, especially room temperature and airflow patterns, are easily manipulated by the members of the surgical team. In the following discussion, we will examine these elements to better understand the clinical ramifications of adjustments and accommodations that are frequently made to meet the requirements of both the surgical staff and the patient.


Assuntos
Meio Ambiente , Salas Cirúrgicas/normas , Local de Trabalho/normas , Humanos , Umidade/normas , Iluminação/normas , Saúde Ocupacional/normas , Temperatura , Ventilação/métodos , Ventilação/normas
10.
Eur J Pharm Biopharm ; 100: 47-57, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26686650

RESUMO

In a previous study, hydroxypropyl cellulose (HPC)-based capsular shells prepared by injection molding and intended for pulsatile release were successfully coated with 10mg/cm(2) Eudragit® L film. The suitability of HPC capsules for the development of a colon delivery platform based on a time dependent approach was demonstrated. In the present work, data logging devices (PyroButton®) were used to monitor the microenvironmental conditions, i.e. temperature (T) and relative humidity (RH), during coating processes performed under different spray rates (1.2, 2.5 and 5.5g/min). As HPC-based capsules present special features, a preliminary study was conducted on commercially available gelatin capsules for comparison purposes. By means of PyroButton data-loggers it was possible to acquire information about the impact of the effective T and RH conditions experienced by HPC substrates during the process on the technological properties and release performance of the coated systems. The use of increasing spray rates seemed to promote a tendency of the HPC shells to slightly swell at the beginning of the spraying process; moreover, capsules coated under spray rates of 1.2 and 2.5g/min showed the desired release performance, i.e. ability to withstand the acidic media followed by the pulsatile release expected for uncoated capsules. Preliminary stability studies seemed to show that coating conditions might also influence the release performance of the system upon storage.


Assuntos
Cápsulas/síntese química , Celulose/análogos & derivados , Química Farmacêutica/métodos , Umidade/normas , Temperatura , Celulose/síntese química
11.
J Med Syst ; 40(3): 58, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26660689

RESUMO

In 2010, the Addendum D to ASHRAE Standard 170, "Ventilation of healthcare facilities," lowered the minimum relative humidity (RH) requirement of anesthetizing locations (including operating rooms, operating/surgical cystoscopic rooms, delivery rooms (Caesarean), recovery rooms, critical and intensive care, newborn intensive care, treatment rooms, trauma rooms (crisis or shock), laser eye rooms, newborn nursery suites, and endoscopy rooms) from 30 % to 20 %. The new minimum limit was adopted based on the results of a review paper that suggested that lowering humidity levels will have little or no impact on providing a safe environment for patients, staff, or medical equipment. That review paper reached this conclusion by assuming that there were no medical device failures due to electrostatic discharge (ESD). However, in an examination of the FDA's MAUDE database of reported defects and recalls, we identified numerous medical device failures explicitly due to ESD. This paper presents technical reliability and safety concerns regarding the new guidelines and recommends that such changes should not be implemented and that the guidelines should be revoked.


Assuntos
Falha de Equipamento , Umidade/normas , Salas Cirúrgicas/normas , Eletricidade Estática/efeitos adversos , Ventilação/normas , Humanos , Reprodutibilidade dos Testes
12.
In. Bello Guti�rrez, Bruno. Eventos naturales, desastres y salubrismo. La Habana, ECIMED, 2015. .
Monografia em Espanhol | CUMED | ID: cum-61236
13.
An. R. Acad. Farm ; 81(5): 84-100, 2015. graf, ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-146986

RESUMO

En el presente trabajo se realiza un estudio climático y bioclimático del Balneario de la villa de Olmedo. Este análisis se ha llevado a cabo utilizando datos de precipitación, temperatura, humedad relativa y viento, que se han obtenido de las estaciones de AEMET ubicadas en torno a Olmedo. Se han obtenido los valores medios mensuales para cada parámetro climático, así como los valores extremos, la frecuencia de superación de determinados umbrales, las tendencias a largo plazo y los valores de determinados índices climáticos. Para el análisis bioclimático se han utilizado los datos de temperatura y humedad relativa y se han calculado los índices climatológicos de confort y de sensación térmica


An account of the geographical position of Villa Olmedo's Spa is given. Including a brief history of it and its situation nowadays. A particularly reference it is made about their proprietaries and the first chemical composition of the mineral medicinal waters of this spa and about the notices in relationship the date in which it was open (2006) and another ones in relationship the medically effects of the waters and muthbath


Assuntos
Clima , /análise , /métodos , Termometria/instrumentação , Termometria/métodos , Termometria , Análise de Dados/análise , Análise de Dados/métodos , Temperatura , 19045/análise , 19045/métodos , Umidade/normas
14.
Eur J Pharm Biopharm ; 86(3): 532-43, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24380678

RESUMO

The current trend in the pharmaceutical industry to move from batch-wise to continuous production processes strengthens the need for monitoring and controlling the process in-line. The ConsiGma™ continuous tableting line collects data of the different subunits in real-time, but these are not really used. In this paper the data of the six-segmented fluidized bed dryer in the line are used for the development and evaluation of a mass and energy balance. The objectives are multiple: (1) prediction of the moisture content of the granules leaving the dryer solely based on the currently logged data and (2) prediction of the gas outlet temperature to check the mass balances. Once a validated system is established the gas temperature in different horizontal sections of the drying unit can be predicted. Calculations are also used to identify errors in the system and to propose alternative sensor locations. A calibration is performed in order to predict the evaporation rate. The balances were able to predict both the moisture content of the granules at the end of the drying process and the gas outlet temperature quite accurately. Combining the gathered information with the height of the bed in the fluidized bed can be used to predict the gas temperature in different horizontal sections of the dryer. An extra sensor measuring the gas temperature and the humidity at the wet transfer line would increase the accuracy of the calculations. An extra gas velocity sensor at the outlet would be useful to incorporate an extra supervision of the calculations.


Assuntos
Química Farmacêutica/métodos , Dessecação/métodos , Preparações Farmacêuticas/química , Bases de Dados Factuais , Umidade/normas , Preparações Farmacêuticas/análise , Temperatura
17.
Bioanalysis ; 5(15): 1863-71, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23905860

RESUMO

BACKGROUND: For shipping and storage, dried blood spot (DBS) samples must be sufficiently dry to protect the integrity of the sample. When the blood is spotted the humidity has the potential to affect the size of the spot created and the speed at which it dries. RESULTS: The area of DBS produced on three types of substrates were not affected by the humidity under which they were generated. DBS samples reached a steady moisture content 150 min after spotting and 90 min for humidities less than 60% relative humidity. All packaging materials examined provided some degree of protection from external extreme conditions. However, none of the packaging examined provided a total moisture barrier to extreme environmental conditions. CONCLUSION: Humidity was shown not to affect the spot area and DBS samples were ready for shipping and storage 2 h after spotting. The packing solutions examined all provided good protection from external high humidity conditions.


Assuntos
Teste em Amostras de Sangue Seco/métodos , Teste em Amostras de Sangue Seco/normas , Umidade , Manejo de Espécimes/métodos , Manejo de Espécimes/normas , Humanos , Umidade/normas , Embalagem de Produtos/métodos , Embalagem de Produtos/normas , Fatores de Tempo
19.
J Pharm Sci ; 102(2): 401-14, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23192744

RESUMO

The objective of the study was to compare the effectiveness of trehalose with that of melibiose in protecting a monoclonal antibody (rituximab) from aggregation, fragmentation, and secondary structure alterations during processing and subsequent storage. Because reducing disaccharides such as melibiose participate in Maillard reaction with proteins, especially in the presence of water, the lyophilizates were stored under different relative humidity (RH 5%, 11%, and 23%) atmospheres. Freeze drying was shown to cause clear alterations in rituximab secondary structure, an increase in noncovalent protein aggregation, and in some cases fragmentation. However, these changes were less pronounced in the formulation containing melibiose. Storing the lyophilizates under low RH (5%) proved to be most harmful to the stability of rituximab, intensifying secondary structure alterations and increasing protein aggregate content. Again, these changes were less aggravated in the formulation containing melibiose. Surprisingly, the concentration of aggregates larger than 1 µm decreased in some cases during storage at RH 11% and 23%. There was no indication that storage even under the highest RH (23%) would have caused significant amounts of Maillard reaction end products to be formed during 3 months of storage.


Assuntos
Anticorpos Monoclonais Murinos/química , Atmosfera , Química Farmacêutica/métodos , Umidade , Melibiose/química , Trealose/química , Anticorpos Monoclonais Murinos/análise , Estabilidade de Medicamentos , Liofilização/métodos , Umidade/normas , Melibiose/análise , Rituximab , Trealose/análise
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