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Journal of Thermal Biology Jan 2024Ice slurry ingestion during prolonged exercises may improve performance in hot environments; however, the ideal amount and timing of ingestion are still uncertain. We...
Ad libitum ice slurry ingestion and half-marathon performance in a hot environment: A study comparing the effects of the amount and moment of ingestion between ice slurry and water at 37 °C.
Ice slurry ingestion during prolonged exercises may improve performance in hot environments; however, the ideal amount and timing of ingestion are still uncertain. We determined whether ad libitum ice slurry ingestion influences physiological and perceptual variables and half-marathon performance while comparing the effects of the amount and moment of ingestion between ice slurry and water at 37 °C. Ten trained participants (28 ± 2 years; mean and SD) were required to run two half marathons while consuming either ice slurry (-1 °C; Ad-1) or water (37 °C; 37 CE) ad libitum. They then performed two other half marathons where, during one, they were required to ingest an amount of water equivalent to the amount consumed during the Ad-1 trial (Pro37), and in the other, to ingest ice slurry in the amount consumed during the 37 CE trial (Pro-1). During the half marathons, dry-bulb temperature and relative humidity were controlled at 33.1 ± 0.3 °C and 60 ± 3%, respectively. Ad-1 ingestion (349.6 ± 58.5 g) was 45% less than 37 CE ingestion (635.5 ± 135.8 g). Physical performance, heart rate, perceived exertion, body temperatures, and thermal perception were not influenced by the temperature or amount of beverage ingestion. However, a secondary analysis suggested that lower beverage ingestion was associated with improved performance (Ad-1 + Pro37 vs. 37 CE + Pro-1: -4.0 min, Cohen's d = 0.39), with a significant relationship between lower beverage ingestion and faster running time (b = 0.02, t = 4.01, p < 0.001). In conclusion, ice slurry ingestion does not affect performance or physiological or perceptual variables during a half marathon in a hot environment. Preliminary evidence suggests that lower beverage ingestion (ice slurry or warm water) is associated with improved performance compared to higher ingestion.
Topics: Humans; Water; Body Temperature; Body Temperature Regulation; Ice; Marathon Running; Hot Temperature; Eating
PubMed: 38232473
DOI: 10.1016/j.jtherbio.2023.103781 -
Scientific Reports Mar 2024Land use change and atmospheric composition, two drivers of climate change, can interact to affect both local and remote climate regimes. Previous works have considered...
Land use change and atmospheric composition, two drivers of climate change, can interact to affect both local and remote climate regimes. Previous works have considered the effects of greenhouse gas buildup in the atmosphere and the effects of Amazon deforestation in atmospheric general circulation models. In this study, we investigate the impacts of the Brazilian Amazon savannization and global warming in a fully coupled ocean-land-sea ice-atmosphere model simulation. We find that both savannization and global warming individually lengthen the dry season and reduce annual rainfall over large tracts of South America. The combined effects of land use change and global warming resulted in a mean annual rainfall reduction of 44% and a dry season length increase of 69%, when averaged over the Amazon basin, relative to the control run. Modulation of inland moisture transport due to savannization shows the largest signal to explain the rainfall reduction and increase in dry season length over the Amazon and Central-West. The combined effects of savannization and global warming resulted in maximum daily temperature anomalies, reaching values of up to 14 °C above the current climatic conditions over the Amazon. Also, as a consequence of both climate drivers, both soil moisture and surface runoff decrease over most of the country, suggesting cascading negative future impacts on both agriculture production and hydroelectricity generation.
PubMed: 38429332
DOI: 10.1038/s41598-024-55176-5 -
ACS Applied Materials & Interfaces Oct 2023The superhydrophobic properties of material surfaces have attracted significant research and practical development in a wide range of applications. In the present study,...
The superhydrophobic properties of material surfaces have attracted significant research and practical development in a wide range of applications. In the present study, a superhydrophobic coating was fabricated using a vapor-phase sublimation and deposition process. This process offers several advantages, including a controllable and tunable superhydrophobic property, a dry and solvent-free process that uses well-defined water/ice templates during fabrication, and a coating technology that is applicable to various substrates, regardless of their dimensions or complex geometric configurations. The fabrication process exploits time-dependent condensation to produce ice templates with a controlled surface morphology and roughness. The templates are sacrificed via vapor sublimation, which results in mass transfer of water vapor out of the system. A second vapor source of a polymer precursor is then introduced to the system, and deposition occurs upon polymerization on the iced templates, replicating the same topologies from the iced templates. The continuation of the co-current sublimation and deposition processes finally renders permanent hierarchical structures of the polymer coatings that combine the native hydrophobic property of the polymer and the structured property by the sacrificed ice templates, achieving a level of superhydrophobicity that is tunable from 90° to 164°. The experiments demonstrated the use of [2,2]paracyclophanes as the starting materials for forming the superhydrophobic coatings of poly(-xylylenes) on substrate surfaces. In comparison to conventional vapor deposition of poly(-xylylenes), which resulted in dense thin-film coatings with only a moderate water contact angle of approximately 90°, the reported superhydrophobic coatings and fabrication process can achieve a high water contact angle of 164°. Demonstrations furthermore revealed that the proposed coatings are durable while maintaining superhydrophobicity on various substrates, including an intraocular lens and a cardiovascular stent, even against harsh treatment conditions and varied solution compositions used on the substrates.
PubMed: 37793161
DOI: 10.1021/acsami.3c06684 -
Journal of Breath Research Dec 2023Secondary electrospray ionization-high resolution mass spectrometry (SESI-HRMS) is an established technique in the field of breath analysis characterized by its short...
Secondary electrospray ionization-high resolution mass spectrometry (SESI-HRMS) is an established technique in the field of breath analysis characterized by its short analysis time, as well as high levels of sensitivity and selectivity. Traditionally, SESI-HRMS has been used for real-time breath analysis, which requires subjects to be at the location of the analytical platform. Therefore, it limits the possibilities for an introduction of this methodology in day-to-day clinical practice. However, recent methodological developments have shown feasibility on the remote sampling of exhaled breath in Nalophan® bags prior to measurement using SESI-HRMS. To further explore the range of applications of this method, we conducted a proof-of-concept study to assess the impact of the storage time of exhaled breath in Nalophan® bags at different temperatures (room temperature and dry ice) on the relative intensities of the compounds. In addition, we performed a detailed study of the storage effect of 27 aldehydes related to oxidative stress. After 2 h of storage, the mean of intensity of allsignals relative to the samples analyzed without prior storage remained above 80% at both room temperature and dry ice. For the 27 aldehydes, the mean relative intensity losses were lower than 20% at 24 h of storage, remaining practically stable since the first hour of storage following sample collection. Furthermore, the mean relative intensity of most aldehydes in samples stored at room temperature was higher than those stored in dry ice, which could be related to water vapor condensation issues. These findings indicate that the exhaled breath samples could be preserved for hours with a low percentage of mean relative intensity loss, thereby allowing more flexibility in the logistics of off-line SESI-HRMS studies.
Topics: Humans; Dry Ice; Polyethylene Terephthalates; Breath Tests; Exhalation; Aldehydes
PubMed: 38029449
DOI: 10.1088/1752-7163/ad10e1 -
International Journal of Food Science 2023The study is aimed at assessing the impacts of postharvest handling practices on the quality and safety of tuna sold at the Honiara Fish Market (HFM), Solomon Islands....
The study is aimed at assessing the impacts of postharvest handling practices on the quality and safety of tuna sold at the Honiara Fish Market (HFM), Solomon Islands. Two major approaches were adopted: (1) face-to-face interviews of 60 participants using questionnaires and physical observations of the supply chains and postharvest handling practices and (2) determination of time-temperature, quality index, histamine, and microbial load of tuna and contact surfaces. Sampling was conducted on both the wet season (WS) and dry season (DS), of which 36 samples from both batches of fresh tuna (FT) and brined tuna (BT) were analyzed. Three critical control points (CCPs) were identified in the supply chains of both FT and BT, where samples were obtained for scientific analyses. The average body temperature for WS tuna exposed for 9-10 h with low or no ice after catch was 3°C for FT and 15°C for BT, while DS samples were 26°C and 31°C for FT and BT, respectively. The quality index (QI) for WS showed a significant difference ( < 0.05) at 0 for FT and 8 for BT, while both DS showed a significant increase at 16 for BT and 5 for FT. Histamine levels for all the samples increased across the three CCPs, however with levels <50 mg/L, while microbial load for both seasons and for both samples were within the required specifications. However, contact surfaces for both seasons revealed high levels of microbial contamination. This study reveals that poor handling practices along the tuna supply chains of fish sold at the HFM were observed; however, all the tuna was safe for consumption when cooked properly.
PubMed: 37637216
DOI: 10.1155/2023/6594017 -
Animals : An Open Access Journal From... Sep 2023Coliforms are relatively common in aquatic environments, but their concentrations can be increased by environmental changes and anthropogenic activities, thus impacting...
Coliforms are relatively common in aquatic environments, but their concentrations can be increased by environmental changes and anthropogenic activities, thus impacting fisheries resources. To determine the microbiological quality in the octopus production chain (capture, post-capture, processing and commercialization), total (TC) and fecal (FC) coliforms were quantified in sea water, fresh octopus, fresh water, ice and octopus in two presentations: packed in ice and boiled. Samples came from fishing zones Enmedio, Chopa and La Gallega at the Veracruz Reef System (VRS) during dry, rainy and windy seasons. The coliforms were determined using the most probable number technique (MPN). The most relevant results indicated that octopus packed in ice coming from the commercialization stage had FC levels >540 MPN/100 g, which exceeded the permissible limits (230 MPN/100 g). Therefore, these products present a risk for human consumption. Differences in FC were observed in octopuses between the three fishing zones (H = 8.697; = 0.0129) and among the three climatic seasons, increasing during the rainy season, highlighting La Gallega with 203.33 ± 63 MPN (H = 7.200; = 0.0273). The results provide evidence of the environmental and anthropogenic influences on coliform concentrations and the urgent need to implement an efficient cold chain throughout octopus production stages with adequate handling practices to reverse this situation.
PubMed: 37835655
DOI: 10.3390/ani13193049 -
The Journal of Physical Chemistry... Feb 2024We introduce a computational tool for the quantum-mechanical simulation of anharmonic infrared and Raman vibrational spectra of materials. The approach, implemented in...
We introduce a computational tool for the quantum-mechanical simulation of anharmonic infrared and Raman vibrational spectra of materials. The approach, implemented in the CRYSTAL software, stems from Taylor's expansion of the potential energy surface (PES) on the basis of normal modes up to cubic and quartic terms. The PES can be sampled with four different numerical schemes at the level of density functional theory (DFT), with local, generalized-gradient, and hybrid density functional approximations. Anharmonic states are obtained by solving Shrödinger's nuclear equation with either the vibrational self-consistent field (VSCF) or vibrational configuration interaction (VCI) methods. Nuclear quantum effects (NQEs) are thus fully accounted for. Infrared intensities are computed numerically through a Berry phase approach or analytically through a coupled-perturbed (CP) approach. Raman intensities are computed analytically via the CP approach. A variety of anharmonic features of vibrational spectra of materials can be simulated, including band shifts, combination bands, overtones, resonances (first-order Fermi, second-order Darling-Dennison), and hot bands. We showcase the effectiveness of the approach on the description of a first-order Fermi resonance (FR) in CO dry ice: a challenging test-case given that the FR occurs in the Raman spectrum, requires NQEs, and involves two- and three-mode couplings. Fundamental mechanistic differences with respect to the well-known FR in molecular CO are addressed. This application represents the first quantum-mechanical, periodic description of FR in dry ice.
PubMed: 38241167
DOI: 10.1021/acs.jpclett.3c03372 -
Chemosphere Dec 2023The environmental distribution of per- and polyfluoroalkyl substances (PFAS) in water, snow, sediment and soil samples taken along the west coast of Spitsbergen in the...
The environmental distribution of per- and polyfluoroalkyl substances (PFAS) in water, snow, sediment and soil samples taken along the west coast of Spitsbergen in the Svalbard archipelago, Norwegian Arctic, was determined. The contribution of potential local primary sources (wastewater, firefighting training site at Svalbard airport, landfill) to PFAS concentrations and long-range transport (atmosphere, ocean currents) were then compared, based on measured PFAS levels and composition profiles. In remote coastal and inland areas of Spitsbergen, meltwater had the highest mean ΣPFAS concentration (6.5 ± 1.3 ng L), followed by surface snow (2.5 ± 1.7 ng L), freshwater (2.3 ± 1.1 ng L), seawater (1.05 ± 0.64 ng L), lake sediments (0.084 ± 0.038 ng g dry weight (dw)) and marine sediments (
ice during the Arctic spring is an important diffuse local PFAS source. This source may become even more important with climate warming-induced melting of Arctic glaciers and ice sheets. Further studies of mobilisation and transport of PFAS in the Arctic region are needed to confirm this trend. Topics: Svalbard; Water Pollutants, Chemical; Environmental Monitoring; Fluorocarbons; Water; Lakes; Alkanesulfonates; Arctic Regions; Soil
PubMed: 37852382
DOI: 10.1016/j.chemosphere.2023.140463 -
Journal of Dairy Science Dec 2023Commercial manufacturing of dairy products involves the addition of dairy ingredients (such as nonfat dry milk and milk protein concentrates), as well as nondairy...
Commercial manufacturing of dairy products involves the addition of dairy ingredients (such as nonfat dry milk and milk protein concentrates), as well as nondairy additives (such as gums, stabilizers, emulsifiers, and texture modifiers) to get the best product appearance, maintain the product quality, and extend shelf life. Though these nondairy additives are not harmful, consumers do not prefer them in dairy food formulations. Therefore, the dairy industry is working on improving the inherent functionality of dairy ingredients using different processes. Recently, fibrillation emerged as a new technique to convert globular proteins such as whey proteins into fibrils, which provide enhanced viscosity, foaming, and emulsification capacity. Therefore, skim milk was subjected to microfiltration followed by ultrafiltration of microfiltration permeate to fractionate whey proteins. Then, whey proteins were selectively fibrillated and mixed back with other streams of microfiltration and ultrafiltration to get fibrillated skim milk. Fibrillated skim milk was spray-dried to get fibrillated nonfat dry milk (NDM). Visible whey protein fibrils were observed in reconstituted fibrillated NDM, which showed survival of fibrils in fibrillated NDM. Fibrillated NDM showed significantly higher viscosity than control NDM. Fibrillated NDM also showed higher emulsification capacity, foaming capacity, and stability than the control NDM but lower gel strength. Considering the improved functionality of fibrillated NDM, they can be used in product formulations such as ice cream mix, where the thickening of a solution, good emulsification, and foaming properties are required.
Topics: Animals; Whey Proteins; Milk Proteins; Milk; Ice Cream; Viscosity; Food Handling
PubMed: 37641309
DOI: 10.3168/jds.2023-23599 -
Journal of Functional Biomaterials Sep 2023Human trabecular meshwork is a sieve-like tissue with large pores, which plays a vital role in aqueous humor outflow. Dysfunction of this tissue can occur, which leads...
Human trabecular meshwork is a sieve-like tissue with large pores, which plays a vital role in aqueous humor outflow. Dysfunction of this tissue can occur, which leads to glaucoma and permanent vision loss. Replacement of trabecular meshwork with a tissue-engineered device is the ultimate objective. This study aimed to create a biomimetic structure of trabecular meshwork using electrospinning. Conventional electrospinning was compared to cryogenic electrospinning, the latter being an adaptation of conventional electrospinning whereby dry ice is incorporated in the fiber collector system. The dry ice causes ice crystals to form in-between the fibers, increasing the inter-fiber spacing, which is retained following sublimation. Structural characterization demonstrated cryo-scaffolds to have closer recapitulation of the trabecular meshwork, in terms of pore size, porosity, and thickness. The attachment of a healthy, human trabecular meshwork cell line (NTM) to the scaffold was not influenced by the fabrication method. The main objective was to assess cell infiltration. Cryo-scaffolds supported cell penetration deep within their structure after seven days, whereas cells remained on the outer surface for conventional scaffolds. This study demonstrates the suitability of cryogenic electrospinning for the close recapitulation of trabecular meshwork and its potential as a 3D in vitro model and, in time, a tissue-engineered device.
PubMed: 37888155
DOI: 10.3390/jfb14100490