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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 -
Health Science Reports Sep 2023Winter endurance athletes have a high prevalence of exercise-induced bronchoconstriction (EIB) and asthma, probably due to repeated and prolonged inhalation of cold and...
BACKGROUND AND AIMS
Winter endurance athletes have a high prevalence of exercise-induced bronchoconstriction (EIB) and asthma, probably due to repeated and prolonged inhalation of cold and dry air. Heat- and moisture-exchanging devices (HME) warm and humidify inhaled air and prevent EIB. The aim of this study was to share cross-country skiers and biathletes' experiences of training and competition in low temperatures, views on temperature limits, usage of HME, and consequences of cold exposure on their health.
METHODS
Eleven Swedish World Championship or Olympic medalists in cross-country skiing and biathlon were interviewed and transcripts were analyzed using qualitative content analysis.
RESULTS
Participants described how cold temperatures predominantly affected the airways, face, and extremities. During training, extreme cold was managed by choosing warmer clothing, modification of planned sessions, use of HME, delaying training, or changing location. In competition, participants described limited possibility for such choices and would prefer adjustment of existing rules (i.e., more conservative temperature limits), especially since they understood elite skiing in low temperatures to present an occupational hazard to their health. Participants had at times used HMEs during training in cold environments but described mixed motives for their use-that HMEs warm and humidify cold inhaled air but introduce additional resistance to breathing and can cause problems due to mucus and ice build-up. Skiers also perceived that they had become more sensitive to cold during the latter part of their careers.
CONCLUSIONS
The present study gives a unique insight into the "cold" reality of being an elite athlete in skiing and biathlon. Cold exposure results in negative health consequences that are preventable, which means that rules must be followed, and organizers should acknowledge responsibility in protecting athletes from occupational hazards. Development of evidence-based guidelines for protection of athletes' respiratory health should be a focus for future translational research.
PubMed: 37662540
DOI: 10.1002/hsr2.1511 -
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 Dairy Science Nov 2023The distribution of phospholipids (PL) within the fat and serum phase of ice cream manufacturing was evaluated through partition coefficients (K) after mixing,...
The distribution of phospholipids (PL) within the fat and serum phase of ice cream manufacturing was evaluated through partition coefficients (K) after mixing, pasteurization, freezing, and hardening. Ice creams containing about 40.41 ± 3.45 (± standard deviation; control formulation) and 112.29 ± 9.06 (enriched PL formulation) mg of PL per g of fat were formulated with nonfat dry milk and β-serum, respectively. Overall, the K were lower than 1, indicating that the PL were predominantly found in the fat phase, and only a small amount was left in the serum and sediment. Confocal micrographs visually confirmed this generalization. The addition of PL significantly increased the viscosity of the mixes between 4- and 9-fold, depending on the shear rate. Additionally, mixes containing high PL exhibited higher yield stress than those formulated with low PL (0.15 ± 0.09 and 0.016 ± 0.08 Pa, respectively). Ice creams with high PL delayed the onset of meltdown and exhibited a slower rate of a meltdown than low-PL ice creams (18.53 ± 0.57 and 14.83 ± 0.85 min, and 1.01 ± 0.05 and 0.71 ± 0.04% min, respectively). This study provides useful guidelines for manufacturing ice cream enriched in milk PL. Additionally, the use of β-serum, a byproduct stream, as a source of PL is illustrated. The development will require studying the sensorial description of the product as well as consumer acceptance.
PubMed: 37641266
DOI: 10.3168/jds.2022-23145 -
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 -
Pharmaceutics Aug 2023In this work, a non-isothermal pore network (PN) model with quasi-steady vapor transport and transient heat transfer is presented for the first time for the application...
In this work, a non-isothermal pore network (PN) model with quasi-steady vapor transport and transient heat transfer is presented for the first time for the application of primary freeze drying. The pore-scale resolved model is physically based and allows for the investigation of correlations between spatially distributed structure and transport conditions. The studied examples were regular PN lattices with a significantly different structure, namely a spatially homogeneous PN, also denoted as monomodal PN, and a PN with significant structure variation, referred to as bimodal PN because of its bimodal pore size distribution. The material properties selected for the solid skeleton in this study are equivalent to those of maltodextrin. The temperature ranges applied here were -28 °C to -18 °C in the PN and -42 °C in the surrounding environment. The environmental vapor pressure was 10 Pa. The PNs were dried with constant temperature boundary conditions, and heat was transferred at the top side by the vapor leaving the PN. It is shown how the structural peculiarities affect the local heat and mass transfer conditions and result in a significant widening of the sublimation front in the case of the bimodal PN. The possibility of spatially and temporally resolved front structures is a unique feature of the PN model and allows the study of situations that are not yet described by classical continuum approaches, namely heterogeneous frozen porous materials. As demonstrated by the thin layers studied here, the pore-scale simulations are of particular interest for such situations, such as in lyomicroscopes or collagen scaffolds, where a length-scale separation between dry and ice-saturated regions is not possible.
PubMed: 37631345
DOI: 10.3390/pharmaceutics15082131 -
International Journal of Molecular... Aug 2023In Antarctica, ice-free areas can be found along the coast, on mountain peaks, and in the McMurdo Dry Valleys, where microorganisms well-adapted to harsh conditions can...
In Antarctica, ice-free areas can be found along the coast, on mountain peaks, and in the McMurdo Dry Valleys, where microorganisms well-adapted to harsh conditions can survive and reproduce. Metabolic analyses can shed light on the survival mechanisms of Antarctic soil communities from both coastal sites, under different plant coverage stages, and inner sites where slow-growing or dormant microorganisms, low water availability, salt accumulation, and a limited number of primary producers make metabolomic profiling difficult. Here, we report, for the first time, an efficient protocol for the extraction and the metabolic profiling of Antarctic soils based on the combination of NMR spectroscopy and mass spectrometry (MS). This approach was set up on samples harvested along different localities of Victoria Land, in continental Antarctica, devoid of or covered by differently developed biological crusts. NMR allowed for the identification of thirty metabolites (mainly sugars, amino acids, and organic acids) and the quantification of just over twenty of them. UPLC-MS analysis identified more than twenty other metabolites, in particular flavonoids, medium- and long-chain fatty acids, benzoic acid derivatives, anthracenes, and quinones. Our results highlighted the complementarity of the two analytical techniques. Moreover, we demonstrated that their combined use represents the "gold standard" for the qualitative and quantitative analysis of little-explored samples, such as those collected from Antarctic soils.
Topics: Soil; Antarctic Regions; Pilot Projects; Chromatography, Liquid; Tandem Mass Spectrometry; Metabolomics
PubMed: 37569716
DOI: 10.3390/ijms241512340 -
Foods (Basel, Switzerland) Jul 2023In this paper, the quality change of Yesso scallop () in the process of anhydrous storage and transportation after cold acclimation and induced dormancy was studied, and...
In this paper, the quality change of Yesso scallop () in the process of anhydrous storage and transportation after cold acclimation and induced dormancy was studied, and the regulation mechanism of quality degradation during storage and transportation in the process of gradient chilling stress and drying exposure was further explored. The results show that, when transferred from hydrous to anhydrous states, the breathing pattern of the scallops changed from aerobic to anaerobic. Their gill filaments were altered and their apparent vitality constantly declined, which was reflected by the edge shrinkage of the pallium and the direct proportions of the edge reduction rate and the stimulus response period. After being in the anhydrous state for 4 d, the AEC value dropped to 67.59%. At this time, if they were placed under hydration again, the scallops resumed a good growth state. By proteomics analysis, it was revealed that cold acclimation and dry exposure mainly led to changes in biological functions and pathways, such as mitochondrial inner membrane and ATP hydrolysis activity. In addition, it can be seen from the functional annotation and enrichment analysis of the metabolite KEGG that cold acclimation promoted the purine metabolism of scallops, while dry exposure inhibited the metabolism of saturated fatty acids. In this study, the infrared sensing mode was used for the first time, too, in order to record the heart-rate changes of the scallops during circulation, which shows that non-destructive vitality monitoring of is feasible.
PubMed: 37569171
DOI: 10.3390/foods12152902 -
Journal of Pain and Symptom Management Nov 2023Thirst and xerostomia are significant and highly distressing symptoms experienced by patients receiving palliative and end-of-life care.
CONTEXT
Thirst and xerostomia are significant and highly distressing symptoms experienced by patients receiving palliative and end-of-life care.
OBJECTIVES
Determine a reduction of thirst intensity and perceptions of dry mouth on a numerical scale following both the experimental intervention (mini mint ice cubes) and control (plain ice chips).
METHODS
Cross-over Randomized Controlled Trial (RCT) to assess the effectiveness of novel intervention in the treatment of dry mouth and the sensation of thirst in palliative care patients.
RESULTS
Patients rated the severity of their symptoms of dry mouth and thirst using a numeric rating scale (NRS). On commencing the study and preintervention, all patients suffered severe dry mouth and thirst (≥5/10). Mint and plain ice cubes produced improvement of symptoms immediately after interventions. Results from dry mouth ratings show, a decrease of 1.6 points for plain ice cubes (P < 0.0001), on average, ratings for mint ice cubes decreased 3.7 (P < 0.0001). For the sensation of thirst, the plain ice cube intervention group rating decreased 1.7 points (P < 0.006), ratings for mint ice cubes decreased 3.4 points (P < 0.0001). The average decrease in dry mouth and thirst intensity scores from preintervention to postintervention were significantly greater for mint ice cubes (P < 0.05) and 86.6% of patients preferred mint ice cubes.
CONCLUSION
This trial found that while usual mouth care and the intervention were both able to reduce the intensity of dry mouth and the sensation of thirst, the mint intervention had a greater response.
PubMed: 37562697
DOI: 10.1016/j.jpainsymman.2023.08.005 -
Frontiers in Microbiology 2023The Antarctic McMurdo Dry Valleys are geologically diverse, encompassing a wide variety of soil habitats. These environments are largely dominated by microorganisms,...
INTRODUCTION
The Antarctic McMurdo Dry Valleys are geologically diverse, encompassing a wide variety of soil habitats. These environments are largely dominated by microorganisms, which drive the ecosystem services of the region. While altitude is a well-established driver of eukaryotic biodiversity in these Antarctic ice-free areas (and many non-Antarctic environments), little is known of the relationship between altitude and microbial community structure and functionality in continental Antarctica.
METHODS
We analysed prokaryotic and lower eukaryotic diversity from soil samples across a 684 m altitudinal transect in the lower Taylor Valley, Antarctica and performed a phylogenic characterization of soil microbial communities using short-read sequencing of the 16S rRNA and ITS marker gene amplicons.
RESULTS AND DISCUSSION
Phylogenetic analysis showed clear altitudinal trends in soil microbial composition and structure. Cyanobacteria were more prevalent in higher altitude samples, while the highly stress resistant Chloroflexota and Deinococcota were more prevalent in lower altitude samples. We also detected a shift from Basidiomycota to Chytridiomycota with increasing altitude. Several genera associated with trace gas chemotrophy, including and , were widely distributed across the entire transect, suggesting that trace-gas chemotrophy may be an important trophic strategy for microbial survival in oligotrophic environments. The ratio of trace-gas chemotrophs to photoautotrophs was significantly higher in lower altitude samples. Co-occurrence network analysis of prokaryotic communities showed some significant differences in connectivity within the communities from different altitudinal zones, with cyanobacterial and trace-gas chemotrophy-associated taxa being identified as potential keystone taxa for soil communities at higher altitudes. By contrast, the prokaryotic network at low altitudes was dominated by heterotrophic keystone taxa, thus suggesting a clear trophic distinction between soil prokaryotic communities at different altitudes. Based on these results, we conclude that altitude is an important driver of microbial ecology in Antarctic ice-free soil habitats.
PubMed: 37555066
DOI: 10.3389/fmicb.2023.1203216