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1.
Build Environ ; 214: 108932, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35221454

RESUMO

Wearing masks to study and work places has become a daily protective measure during the COVID-19 pandemic. In the summer of 2021, environmental parameters were monitored, and students in a university library in Guangzhou, China, were surveyed to analyze the possible symptoms of wearing masks for a long time, and to assess the sensitivity of various body parts to the environmental parameters. Concurrently, the preference of subjects wearing masks for various environmental parameters was also analyzed. Additionally, the relationship between thermal sensation and thermal index was analyzed to identify acceptable and comfortable temperature ranges. The expected duration of wearing masks was counted. Subjects wearing masks had greater requirements for environmental comfort, and reported increased thermal discomfort of the face and head, compared to those without masks. More than 70% of the subjects wearing masks reported that they experienced discomfort on their faces. Among the subjects who experienced discomfort, 62.7% reported that facial fever was the main symptom; while some reported symptoms of dyspnea (25.4%) and rapid heartbeat (9.1%). More than 75% of the subjects were expected to wear masks for 2.0 h or less. Evaluation of environmental thermal sensation, including overall, facial, and head thermal sensation, differed among subjects who wore and did not wear masks. The indexes of neutral Operative temperature/Standard Effective Temperature (T op /SET*) and preferred T op /SET* were lower among subjects with masks than among those without masks. The neutral T op /SET* deviation was 0.3 °C, and the preferred T op /SET* deviation was 0.5 °C. Additionally, the acceptable and comfortable temperature zones differed between the two cases. The subjects who wore masks preferred colder temperatures. These findings indicated that the environmental parameters should be adjusted to improve the thermal comfort of the human body while wearing masks in work or study places.

2.
Chem Eng J ; 405: 126893, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32901196

RESUMO

The unprecedented global spread of the severe acute respiratory syndrome (SARS) caused by SARS-CoV-2 is depicting the distressing pandemic consequence on human health, economy as well as ecosystem services. So far novel coronavirus (CoV) outbreaks were associated with SARS-CoV-2 (2019), middle east respiratory syndrome coronavirus (MERS-CoV, 2012), and SARS-CoV-1 (2003) events. CoV relates to the enveloped family of Betacoronavirus (ßCoV) with positive-sense single-stranded RNA (+ssRNA). Knowing well the persistence, transmission, and spread of SARS-CoV-2 through proximity, the faecal-oral route is now emerging as a major environmental concern to community transmission. The replication and persistence of CoV in the gastrointestinal (GI) tract and shedding through stools is indicating a potential transmission route to the environment settings. Despite of the evidence, based on fewer reports on SARS-CoV-2 occurrence and persistence in wastewater/sewage/water, the transmission of the infective virus to the community is yet to be established. In this realm, this communication attempted to review the possible influx route of the enteric enveloped viral transmission in the environmental settings with reference to its occurrence, persistence, detection, and inactivation based on the published literature so far. The possibilities of airborne transmission through enteric virus-laden aerosols, environmental factors that may influence the viral transmission, and disinfection methods (conventional and emerging) as well as the inactivation mechanism with reference to the enveloped virus were reviewed. The need for wastewater epidemiology (WBE) studies for surveillance as well as for early warning signal was elaborated. This communication will provide a basis to understand the SARS-CoV-2 as well as other viruses in the context of the environmental engineering perspective to design effective strategies to counter the enteric virus transmission and also serves as a working paper for researchers, policy makers and regulators.

3.
Physiol Mol Plant Pathol ; 105: 77-87, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31007376

RESUMO

Here, we report a method to clean cassava plants from viral infections that cause cassava mosaic and brown streak diseases in Africa. Infected plants of resistant or tolerant varieties from Malawi, Mozambique, Kenya, Tanzania and Uganda were cleaned in the UK using a combination of tissue culture, chemotherapy and thermotherapy. In the first cycle of our virus-indexing procedure, we successfully cleaned 27 of the 31 varieties (87%), and after an additional three cleaning cycles, all plants were virus-free. Virus-free tissue-cultured plants were shipped back to Africa for distribution to farmers. This first cross-boundary effort provides important lessons for mitigating the two-major cassava viral diseases.

4.
JHEP Rep ; 5(2): 100603, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36714793

RESUMO

Background & Aims: Induction of potent, HBV-specific immune responses is crucial to control and finally cure HBV. The therapeutic hepatitis B vaccine TherVacB combines protein priming with a Modified Vaccinia virus Ankara (MVA)-vector boost to break immune tolerance in chronic HBV infection. Particulate protein and vector vaccine components, however, require a constant cooling chain for storage and transport, posing logistic and financial challenges to vaccine applications. We aimed to identify an optimal formulation to maintain stability and immunogenicity of the protein and vector components of the vaccine using a systematic approach. Methods: We used stabilizing amino acid (SAA)-based formulations to stabilize HBsAg and HBV core particles (HBcAg), and the MVA-vector. We then investigated the effect of lyophilization and short- and long-term high-temperature storage on their integrity. Immunogenicity and safety of the formulated vaccine was validated in HBV-naïve and adeno-associated virus (AAV)-HBV-infected mice. Results: In vitro analysis proved the vaccine's stability against thermal stress during lyophilization and the long-term stability of SAA-formulated HBsAg, HBcAg and MVA during thermal stress at 40 °C for 3 months and at 25 °C for 12 months. Vaccination of HBV-naïve and AAV-HBV-infected mice demonstrated that the stabilized vaccine was well tolerated and able to brake immune tolerance established in AAV-HBV mice as efficiently as vaccine components constantly stored at 4 °C/-80 °C. Even after long-term exposure to elevated temperatures, stabilized TherVacB induced high titre HBV-specific antibodies and strong CD8+ T-cell responses, resulting in anti-HBs seroconversion and strong suppression of the virus in HBV-replicating mice. Conclusion: SAA-formulation resulted in highly functional and thermostable HBsAg, HBcAg and MVA vaccine components. This will facilitate global vaccine application without the need for cooling chains and is important for the development of prophylactic as well as therapeutic vaccines supporting vaccination campaigns worldwide. Impact and implications: Therapeutic vaccination is a promising therapeutic option for chronic hepatitis B that may enable its cure. However, its application requires functional cooling chains during transport and storage that can hardly be guaranteed in many countries with high demand. In this study, the authors developed thermostable vaccine components that are well tolerated and that induce immune responses and control the virus in preclinical mouse models, even after long-term exposure to high surrounding temperatures. This will lower costs and ease application of a therapeutic vaccine and thus be beneficial for the many people affected by hepatitis B around the world.

5.
Food Chem X ; 16: 100472, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36304207

RESUMO

Reliable prediction of the risk of mycotoxin contamination in post-harvest wheat will aid in improvement of the quality and safety. To establish the relationship between Fusarium pseudograminearum mycotoxins and CO2 production, changes in their respective concentrations were monitored for the artificial contamination of wheat under different values of water activities (0.84 aw, 0.92 aw, and 0.97 aw) and temperatures (20 ℃, 25 ℃, and 30 ℃). Water activity played a significant role in all these processes. CO2 concentration together with moisture content and temperature were used as the main parameters to establish DON and ZEN contamination prediction models. The prediction accuracy for DON was 98.15 % (R2 = 0.990) and 90.74 % for ZEN (R2 = 0.982). These models were combined with T/RH/MC/CO2 multi-parameter integrated sensors to form an early warning system, which offers a great prospect to minimise the risk of DON/ZEN contamination in post-harvest wheat.

6.
Toxicol Rep ; 9: 797-805, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36518443

RESUMO

Background: Moringa stenopetala (Baker f.) Cudof. and Mentha spicata L. are widely used in the traditional system of medicine for the treatment of diabetes, hypertension, digestive problems and various disorders. The leaves formulation of M. stenopetala and M. spicata herbal tea showed better antidiabetic and antihypertensive effects in rodent models. However, its long-term safety profile has not been investigated yet. Thus, this study investigated the subchronic (90 days) oral toxicity of the leaves formulation of M. stenopetala and M. spicata herbal tea in Wistar albino rats. Methods: Four groups of rats (n = 10, with 5/sex/group) were randomly assigned into a control (vehicle) group and three test groups (559.36, 1118.72 and 2237.44 mg/kg, respectively). The three test groups received the herbal tea of M. stenopetala and M. spicata leaves blend daily for 90 days. The control group received distilled water. During the treatment period, clinical signs were observed daily, and food consumption and body weight changes of the rats were measured weekly. At the end of the experiment, macro-pathological, hematological and biochemical parameters were evaluated. Furthermore, histopathology of liver, kidney, heart, stomach and pancreas were examined. Results: Subchronic oral administration of the herbal tea of M. stenopetala and M. spicata leaves blend did not result in death or significant toxicity signs in the treated group rats. Moreover, the herbal tea caused no significant changes on body weight, food intake, organ weight, hematological and biochemical parameters in either sex. However, the serum AST, CK and LDH levels were significantly elevated in rats treated with 2237.44 mg/kg of herbal tea in both sexes. There was no significant alteration in the histology of organs, only minor lesions in the liver, kidney and pancreas were observed. Conclusion: The study results indicate that the herbal tea of M. stenopetala and M. spicata leaves blend is relatively safe/low toxic to rats in subchronic exposure. However, further preclinical (chronic, teratogenic, reproductive and developmental toxicity) studies in animals are required in order to have sufficient safety and toxicity profiles for its use in humans.

7.
Food Chem X ; 14: 100348, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35663601

RESUMO

Compared with the P. longanae-infected longan, the DNP-treated P. longanae-infected fruit represented a higher pulp breakdown index, a higher O2 -. production rate, and a higher MDA content, but the lower activities of APX, SOD and CAT, the lower transcript levels of DlAPX6, DlSOD1, DlSOD2, DlSOD3 and DlCAT1, the lower values of AsA, GSH, flavonoid and total phenolics, a lower scavenging ability of DPPH radical, and a lower value of reducing power. Whereas, the ATP-treated P. longanae-infected samples showed the contrary results. The above findings indicated that the DNP-promoted the pulp breakdown in P. longanae-infected longan was because DNP weakened the capacity of scavenging ROS, raised the O2 -. level, and accelerated the membrane lipids peroxidation. However, the ATP-suppressed the pulp breakdown in P. longanae-infected longan was because ATP improved the capacity of scavenging ROS, reduced the O2 -. level, and reduced the membrane lipids peroxidation.

8.
J Hazard Mater Adv ; 8: 100183, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36619826

RESUMO

The COVID-19 pandemic highlighted public awareness of airborne disease transmission in indoor settings and emphasized the need for reliable air disinfection technologies. This increased awareness will carry in the post-pandemic era along with the ever-emerging SARS-CoV variants, necessitating effective and well-defined protocols, methods, and devices for air disinfection. Ultraviolet (UV)-based air disinfection demonstrated promising results in inactivating viral bioaerosols. However, the reported data diversity on the required UVC doses has hindered determining the best UVC practices and led to confusion among the public and regulators. This article reviews available information on critical parameters influencing the efficacy of a UVC air disinfection system and, consequently, the required dose including the system's components as well as operational and environmental factors. There is a consensus in the literature that the interrelation of humidity and air temperature has a significant impact on the UVC susceptibility, which translate to changing the UVC efficacy of commercialized devices in indoor settings under varying conditions. Sampling and aerosolization techniques reported to have major influence on the result interpretation and it is recommended to use several sampling methods simultaneously to generate comparable and conclusive data. We also considered the safety concerns and the potential safe alternative of UVC, far-UVC. Finally, the gaps in each critical parameter and the future research needs of the field are represented. This paper is the first step to consolidating literature towards developing a standard validation protocol for UVC air disinfection devices which is determined as the one of the research needs.

9.
Saudi J Biol Sci ; 28(7): 3799-3805, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34220234

RESUMO

Predation is one of the significant biotic mortality factors reducing the insect pest population as functional response and the numerical response of the predator are the key factor regulating the population dynamics of predator prey species. This study is aimed to evaluate the functional response of all the developmental stages of Scymnus coccivora Ayyar (Coleoptera: Coccinellidae) against the different densities of cotton mealybug, Phenacoccus solenopsis (Tinsley) (Hemiptera: Pseudococcidae) and the numerical response of female predator. Experiments were carried out in controlled environment laboratory conditions at 25 ± 1 °C temperature, 60 ± 5% relative humidity and photoperiod of 16 h. Number of eggs consumed, number of eggs laid and the Efficiency of Conversion of Ingested food (ECI) were recorded daily. Results from the study revealed that all the developmental stages of S. coccivora exhibited a Type II response. Different parameters such as attack rate (a'), handling time (Th) and the maximum rate of predation were estimated using Roger's random attack equation and Holling Disc equation in which Rogers random attack equation was found best fit. Female has shown the highest attack rate (a') followed by IVth instar grub, male, IIIrd, IInd and Ist instar grub. With low handling time, IVth instar grub has shown maximum predation rate of 76.40 per day followed by female (75.86), male (58.79), IIIrd (22.84), IInd (19.65) and Ist instar grub (15.39). The numerical response increase was curvilinearly related to different prey densities with the highest number of eggs (11.8 ± 3.44) produced at highest prey density (160). The Efficiency of Conversion of Ingested food (ECI) was highest (64.49 ± 8.03) at prey density of 10. Understanding the factors that lead to variation in functional response of predator in natural population will advance our understanding of the effects of predation on individual and the effectiveness of coccinellid predators as biocontrol agent against cotton mealybug.

10.
Toxicol Rep ; 8: 1143-1155, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34150524

RESUMO

Curcumin (CUR) has a long history of use as an antimicrobial, anti-inflammatory and wound healing agent, for the treatment of various skin conditions. Encapsulation in nanocarriers may overcome the administration limitations of CUR, such as lipophilicity and photodegradation. Lipid nanocarriers with different matrix fluidity (Solid Lipid Nanoparticles; SLN, Nanostructured Lipid Carriers; NLC, and Nanoemulsion; NE) were prepared for the topical delivery of curcumin (CUR). The occlusive properties and film forming capacity, as well as the release profile of incorporated CUR, its protection against photodegradation and wound healing were studied in vitro, using empty nanocarriers or free CUR as control. The results suggest that incorporation of CUR in nanocarriers offers a significant protection against photodegradation that is not influenced by the matrix fluidity. However, this characteristic regulates properties such as the occlusion, the release rate and wound healing ability of CUR. Nanoparticles of low fluidity provided better surface occlusion, film forming capacity and retention of the incorporated CUR. All nanocarriers but especially NLC, achieved faster wound healing at lower dose of incorporated CUR. In conclusion, nanotechnology may enhance the action of CUR against skin conditions. Important characteristics of the nanocarrier such as matrix fluidity should be taken into consideration in the design of CUR nanosystems of optimal efficiency.

11.
J Environ Chem Eng ; 8(5): 104429, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32895629

RESUMO

The world is combating the emergence of Coronavirus disease 2019 (COVID-19) caused by novel coronavirus; severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Further, due to the presence of SARS-CoV-2 in sewage and stool samples, its transmission through water routes cannot be neglected. Thus, the efficient treatment of wastewater is a matter of utmost importance. The conventional wastewater treatment processes demonstrate a wide variability in absolute removal of viruses from wastewater, thereby posing a severe threat to human health and environment. The fate of SARS-CoV-2 in the wastewater treatment plants and its removal during various treatment stages remains unexplored and demands immediate attention; particularly, where treated effluent is utilised as reclaimed water. Consequently, understanding the prevalence of pathogenic viruses in untreated/treated waters and their removal techniques has become the topical issue of the scientific community. The key objective of the present study is to provide an insight into the distribution of viruses in wastewater, as well as the prevalence of SARS-CoV-2, and its possible transmission by the faecal-oral route. The review also gives a detailed account of the major waterborne and non-waterborne viruses, and environmental factors governing the survival of viruses. Furthermore, a comprehensive description of the potential methods (physical, chemical, and biological) for removal of viruses from wastewater has been presented. The present study also intends to analyse the research trends in microalgae-mediated virus removal and, inactivation. The review also addresses the UN SDG 'Clean Water and Sanitation' as it is aimed at providing pathogenically safe water for recycling purposes.

12.
Sustain Cities Soc ; 62: 102382, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32834936

RESUMO

The COVID-19 pandemic elicited a global response to limit associated mortality, with social distancing and lockdowns being imposed. In India, human activities were restricted from late March 2020. This 'anthropogenic emissions switch-off' presented an opportunity to investigate impacts of COVID-19 mitigation measures on ambient air quality in five Indian cities (Chennai, Delhi, Hyderabad, Kolkata, and Mumbai), using in-situ measurements from 2015 to 2020. For each year, we isolated, analysed and compared fine particulate matter (PM2.5) concentration data from 25 March to 11 May, to elucidate the effects of the lockdown. Like other global cities, we observed substantial reductions in PM2.5 concentrations, from 19 to 43% (Chennai), 41-53% (Delhi), 26-54% (Hyderabad), 24-36% (Kolkata), and 10-39% (Mumbai). Generally, cities with larger traffic volumes showed greater reductions. Aerosol loading decreased by 29% (Chennai), 11% (Delhi), 4% (Kolkata), and 1% (Mumbai) against 2019 data. Health and related economic impact assessments indicated 630 prevented premature deaths during lockdown across all five cities, valued at 0.69 billion USD. Improvements in air quality may be considered a temporary lockdown benefit as revitalising the economy could reverse this trend. Regulatory bodies must closely monitor air quality levels, which currently offer a baseline for future mitigation plans.

13.
Saf Health Work ; 10(2): 219-223, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31297285

RESUMO

BACKGROUND: Ice cooling vests can cause tissue damage and have no flexibility. Therefore, these two undesirable properties of ice cooling vest were optimized, and the present study was aimed to compare the impact of the optimized ice cooling vest and a commercial paraffin cooling vest on physiological and perceptual strain under controlled conditions. METHODS: For optimizing, hydrogel was used to increase the flexibility and a layer of the ethylene vinyl acetate foam was placed into the inside layer of packs to prevent tissue damage. Then, 15 men with an optimized ice cooling vest, with a commercial paraffin cooling vest, and without a cooling vest performed tests including exercise on a treadmill (speed of 2.8 km/hr and slope of %0) under hot (40°C) and dry (40 %) condition for 60 min. The physiological strain index and skin temperature were measured every 5 and 15 minutes, respectively. The heat strain score index and perceptual strain index were also assessed every 15 minutes. RESULTS: The mean values of the physiological and perceptual indices differed significantly between exercise with and without cooling vests (P < 0.05). However, the difference of the mean values of the indices except the value of the skin temperature during the exercises with the commercial paraffin cooling vest and the optimized ice cooling vest was not significant (P > 0.05). CONCLUSIONS: The optimized ice cooling vest was as effective as the commercial paraffin cooling vest to control the thermal strain. However, ice has a greater latent heat and less production cost.

14.
Acta Pharm Sin B ; 9(1): 19-35, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30766775

RESUMO

In recent years, the coamorphous drug delivery system has been established as a promising formulation approach for delivering poorly water-soluble drugs. The coamorphous solid is a single-phase system containing an active pharmaceutical ingredient (API) and other low molecular weight molecules that might be pharmacologically relevant APIs or excipients. These formulations exhibit considerable advantages over neat crystalline or amorphous material, including improved physical stability, dissolution profiles, and potentially enhanced therapeutic efficacy. This review provides a comprehensive overview of coamorphous drug delivery systems from the perspectives of preparation, physicochemical characteristics, physical stability, in vitro and in vivo performance. Furthermore, the challenges and strategies in developing robust coamorphous drug products of high quality and performance are briefly discussed.

15.
Biol Bull ; 235(1): 43-51, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30160996

RESUMO

Apple snails, in the genus Pomacea, have gained considerable notoriety for their impact on invaded habitats. Louisiana is currently under invasion by Pomacea maculata, which represents a potential threat to the state's valuable plants and cash crops. Insight into the physiology of the invasive snail may assist in developing control measures and enhance our understanding of the processes of adaptation and coevolution that accompany introductions. This paper addresses the capacity, extent, and means by which aquatic apple snails in Louisiana tolerate aerial exposure, as well as the factors that contribute to desiccation tolerance in P. maculata. Invasive P. maculata in Louisiana survived about 10 months of aestivation before 50% mortality was incurred, during which body mass was reduced by only about 30%; mortality and loss of body mass were positively correlated during aestivation. Size affects the loss of body mass in snails under 20 grams. Relative humidity interfered with the induction of aestivation, but it did not significantly affect the loss of body mass. Invasive apple snails in Louisiana also demonstrated the inclination and ability to sustain travel for at least three hours over dry land, at a rate of two meters per hour. The results of this study show that P. maculata is well adapted for survival in the absence of water. The ability to sustain travel over land and to endure long periods of aerial exposure suggests that the dry-down of infested bodies of water would not significantly impact populations of P. maculata in Louisiana.


Assuntos
Adaptação Fisiológica , Distribuição Animal/fisiologia , Espécies Introduzidas , Caramujos/fisiologia , Animais , Tamanho Corporal , Dessecação , Louisiana
16.
Biol Bull ; 235(3): 195-203, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30624116

RESUMO

Global warming may impact biodiversity by disrupting biological interactions, including long-term insect-microbe mutualistic associations. Symbiont-mediated insect tolerance to high temperatures is an ecologically important trait that significantly influences an insect's life history. Disruption of microbial symbionts that are required by insects would substantially impact their pest status. Diaphorina citri, a worldwide citrus pest, is associated with the mutualistic symbionts Candidatus Carsonella ruddii and Candidatus Profftella armatura. Wolbachia is also associated with D. citri, but its contribution to the host is unknown. Symbiont density is dependent on a range of factors, including the thermosensitivity of the host and/or symbiont to heat stress. Here, we predicted that short-term heat stress of D. citri would disrupt the host-symbiont phenological synchrony and differentially affect the growth and density of symbionts. We investigated the effects of exposing D. citri eggs to different temperatures for different periods of time on the growth dynamics of symbionts during the nymphal development of D. citri (first instar to fifth instar) by real-time polymerase chain reaction. Symbiont densities were assessed as the number of gene copies, using specific molecular markers: 16S rRNA for Carsonella and Profftella and ftsZ for Wolbachia. Statistical modeling of the copy numbers of symbionts revealed differences in their growth patterns, particularly in the early instars of heat-shocked insects. Wolbachia was the only symbiont to benefit from heat-shock treatment. Although the symbionts responded differently to heat stress, the lack of differences in symbiont densities between treated and control late nymphs suggests the existence of an adaptive genetic process to restore phenological synchrony during the development of immatures in preparation for adult life. Our findings contribute to the understanding of the potential deleterious effects of high temperatures on host-symbiont interactions. Our data also suggest that the effects of host exposure to high temperatures in symbiont growth are highly variable and dependent on the interactions among members of the community of symbionts harbored by a host. Such dependence points to unpredictable consequences for agroecosystems worldwide due to climate change-related effects on the ecological traits of symbiont-dependent insect pests.


Assuntos
Hemípteros/fisiologia , Temperatura Alta , Simbiose/fisiologia , Animais
17.
Prehosp Disaster Med ; 33(3): 279-287, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29669616

RESUMO

IntroductionPersonal protective equipment (PPE) recommended for use in West Africa during the Ebola outbreak increased risk for heat illness, and countermeasures addressing this issue would be valuable.Hypothesis/ProblemThe purpose of this study was to examine the physiological impact and heat perception of four different personal cooling devices (PCDs) under impermeable PPE during low-intensity exercise in a hot and humid environment using thermal manikin modeling and human testing. METHODS: Six healthy male subjects walked on a treadmill in a hot/humid environment (32°C/92% relative humidity [RH]) at three metabolic equivalents (METs) for 60 minutes wearing PPE recommended for use in West Africa and one of four different personal cooling devices (PCDs; PCD1, PCD2, PCD3, and PCD4) or no PCD for control (CON). The same ensembles were tested with thermal manikin modeling software in the same conditions to compare the results. RESULTS: All PCDs seemed to reduce physiological heat stress characteristics when worn under PPE compared to CON. Both the manikin and human testing provided similar results in core temperature (Tc) and heat sensation (HS) in both magnitude and relationship. While the manikin and human data provided similar skin temperature (Tsk) characterization, Tsk estimation by the manikin seemed to be slightly over-estimated. Weight loss, as estimated by the manikin, was under-estimated compared to the human measurement. CONCLUSION: Personal cooling device use in conjunction with impermeable PPE may be advantageous in mitigating physiological and perceptual burdens of heat stress. Evaluation of PCDs worn under PPE can be done effectively via human or manikin testing; however, Tsk may be over-estimated and weight loss may be under-estimated. Thermal manikin testing of PCDs may provide fast and accurate information to persons recommending or using PCDs with PPE. QuinnT, KimJH, SeoY, CocaA. Comparison of thermal manikin modeling and human subjects' response during use of cooling devices under personal protective ensembles in the heat. Prehosp Disaster Med. 2018;33(3):279-287.


Assuntos
Regulação da Temperatura Corporal , Temperatura Alta , Manequins , Modelos Biológicos , Roupa de Proteção , Temperatura Corporal , Temperatura Baixa , Humanos , Masculino , Adulto Jovem
18.
Biol Bull ; 233(2): 123-134, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29373063

RESUMO

Desiccation is an important limiting factor in the intertidal zone. Generally decreasing seaward, desiccation stress can also be alleviated in wet microhabitats. Juvenile snails are generally more susceptible to desiccation than adults, and, for some species, juveniles must therefore hide in microhabitats to survive emersion. The transition from hiding in safe microhabitats to being able to survive fully exposed for the duration of low tide is not well documented. In this study, we investigated the influence of size on desiccation tolerance in juveniles of the calyptraeid gastropod Crepipatella peruviana to determine the size at which they can first survive exposure to air. Juveniles 2-13 mm long were exposed to 75% or 100% relative humidity for 0.5-6.5 hours. Juveniles smaller than 5 mm in shell length did not survive emersion at 75% relative humidity for even 0.5 hours; surprisingly, most also perished after short exposures to air at 100% relative humidity, suggesting that something other than desiccation stress may also be at play. In marked contrast, 82% of juveniles larger than 6 mm in shell length survived exposure to 75% relative humidity for the full 6.5 hours. In a field survey, no juveniles smaller than 9 mm were found on exposed rock but rather were found only in wet microhabitats. We suggest that the clearly defined size escape from desiccation may reflect a change in gill functioning or a newfound ability to retain water more effectively within the mantle cavity at low tide.


Assuntos
Dessecação , Gastrópodes/fisiologia , Animais , Tamanho Corporal/fisiologia , Gastrópodes/crescimento & desenvolvimento , Análise de Sobrevida
19.
J Biomater Sci Polym Ed ; 28(10-12): 1215-1230, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28277008

RESUMO

Calorimetric and nuclear magnetic relaxation studies on non-freezing water restrained by polysaccharide are introduced together with the historical background of this research field. Non-freezing water restrained by the hydrophilic group of polysaccharide shows no first order thermodynamic phase transition. The amount of non-freezing water calculated from the melting enthalpy of water restrained by various kinds of polysaccharides was collected. Molecular motion of polysaccharides is markedly enhanced by the introduction of non-freezing water and glass transition shifts to the ca. 200 K low temperature side. At the same time, molecular chains rearrange to a more stabilized state, which can be observed as the decrease in heat capacities. 1H nuclear magnetic relaxation studies at a temperature lower than glass transition indicate that a part of the water molecules is closely bound to the backbone proton and is not sufficiently isolated. Calorimetric and nuclear magnetic relaxation studies suggest that non-freezing water inevitably cooperates with matrix polysaccharide molecules.


Assuntos
Temperatura Alta , Polissacarídeos/química , Água/química , Espectroscopia de Ressonância Magnética , Transição de Fase
20.
J Cereal Sci ; 53(2): 225-230, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31217668

RESUMO

Naked barley is an underutilized crop that is suitable for the production of functional food: it contains remarkable amounts of ß-glucans, which are well known for their blood cholesterol and short-time blood sugar regulating properties and their impact on weight regulation. The aim of the present work was to develop naked barley bread with satisfying sensory characteristics and good baking qualities that could augment the intake of dietary fiber, especially ß-glucans and therefore meet the requirements of the EFSA health claim for ß-glucans. The results of the multiple response optimization suggest that the elevated use of water, malt flour and margarine in pure naked barley bread augment the sensory attractiveness whereas the use of acidifier and pre-gelatinized flour has a negative effect on the sensory quality.

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