Reduced Respiration Rate Research Articles

ОСОБЛИВОСТІ ЗАСТОСУВАННЯ ТЕРАПЕВТИЧНИХ ВПРАВ У ДІТЕЙ З ПНЕВМОНІЄЮ В УМОВАХ ДИТЯЧОГО РЕАНІМАЦІЙНОГО ВІДДІЛЕННЯ

Relevance. It has been established that most authors of scientific studies focus on examining the effectiveness of physical therapy (PhT) in children with acute pneumonia during the post-acute and long-term rehabilitation periods, while paying little attention to the acute rehabilitation period, which begins directly in the intensive care unit. There is an urgent need to review and explore possibilities for improving the overall comprehensive approach to the rehabilitation of children with community acquired pneumonia (САР) by applying a set of PhT methods as early as possible in pediatric intensive care settings. Objective of the study. To determine the specifics of applying and evaluate the effectiveness of comprehensive PhT in children with САР hospitalized in the intensive care unit. Materials and methods of the study. Analysis of literature sources; analysis of the nosological structure of pediatric patients treated in the intensive care unit of a regional children’s hospital; clinical research methods; and methods of mathematical statistics. Study population. Twenty adolescents aged 11–13 years diagnosed with acute pneumonia and respiratory failure of grade I or II. The study consisted of a main group and a comparison group with 10 participants in each. Based on an individual approach, a comprehensive PhT program was developed and implemented for children in the main group with САР to be used during the acute rehabilitation period in the intensive care setting. The PhT program for the main group included the following methods: specialized therapeutic exercises from our developed set, special breathing exercises, and additional therapeutic measures as indicated, such as postural bronchial drainage and therapeutic massage with vibration elements. For the comparison group, rehabilitation followed the existing protocol, which involved static breathing exercises (inflating balloons) and therapeutic massage with vibration elements. Effectiveness was monitored based on heart rate, blood oxygen saturation (SpO₂), respiratory rate at rest, and results of functional Stange and Genchi tests. Results and key conclusions. The proposed rehabilitation program facilitated rapid normalization of blood oxygen saturation, a significant reduction in respiratory rate and resting heart rate, and a reliable improvement in functional test outcomes (Stange and Genchi tests). The comprehensive application of PhT methods, tailored to the individual needs of adolescents aged 11–13 years with acute pneumonia and respiratory failure of grade I or II, during the acute rehabilitation period effectively promotes recovery of cardiorespiratory system functions.

The use of noninvasive positive pressure ventilation for severe asthma: a systematic review and meta-analysis of randomized controlled trials with trial sequential analysis.

To evaluate the effectiveness of noninvasive positive pressure ventilation (NPPV) versus standard therapy in severe asthma exacerbations through meta-analysis. Nine randomized controlled trials (344 patients) were analyzed from inception to August 2024. Primary outcomes included respiratory rate, forced expiratory volume in first second (FEV1), and oxygen saturation (SpO2). Random effect models and trial sequential analyses were employed. NPPV demonstrated significant reduction in respiratory rate versus standard therapy (mean difference [MD] -3.97, 95% CI -7.32 to -0.61, p = 0.02), though with high heterogeneity (I2 = 87%). FEV1 showed significant improvement with NPPV (MD 15.56%, 95% CI 6.86 to 24.26, p < 0.001) based on two studies. SpO2 showed no significant improvement (MD 0.62%, 95% CI -0.14 to 1.37, p = 0.11). No differences were found between pediatric and adult populations. Trial sequential analyses indicated insufficient evidence for definitive conclusions regarding respiratory rate and SpO2 improvements. While NPPV may benefit severe asthma patients, particularly in reducing respiratory rate and improving FEV1, current evidence is insufficient for recommending routine clinical use. Larger randomized controlled trials are needed to establish NPPV's effectiveness in severe asthma exacerbation treatment. registration ID CRD42024580051.

Association of ventilation volumes, pressures and rates with the mechanical power of ventilation in patients without acute respiratory distress syndrome: exploring the impact of rate reduction

SummaryIntroductionHigh mechanical power is associated with mortality in patients who are critically ill and require invasive ventilation. It remains uncertain which components of mechanical power – volume, pressure or rate – increase mechanical power the most.MethodsWe conducted a post hoc analysis of a database containing individual patient data from three randomised clinical trials of ventilation in patients without acute respiratory distress syndrome. The primary endpoint was mechanical power. We used linear regression; double stratification to create subgroups of participants; and mediation analysis to assess the impact of changes in volumes, pressures and rates on mechanical power.ResultsA total of 1732 patients were included and analysed. The median (IQR [range]) mechanical power was 12.3 (9.3–17.1 [3.7–50.1]) J.min‐1. In linear regression, respiratory rate (36%) and peak pressure (51%) explained most of the increase in mechanical power. Increasing quintiles of peak pressure stratified on constant levels of respiratory rate resulted in higher risks of high mechanical power (relative risk 2.2 (95%CI 1.8–2.6), p &lt; 0.01), while decreasing quintiles of respiratory rate stratified on constant levels of peak pressure resulted in lower risks of high mechanical power (relative risk 0.2 (95%CI 0.2–0.3), p &lt; 0.01). Mediation analysis showed that a reduction in respiratory rate, with the increase in tidal volume, partially mediates an effect of reduction in mechanical power (average causal mediation effect ‐0.10, 95%CI ‐0.12 to ‐0.09, p &lt; 0.01), but still with a direct effect of tidal volume on mechanical power (average direct effect 0.15, 95%CI 0.11–0.19, p &lt; 0.01).DiscussionIn this cohort of patients without acute respiratory distress syndrome, pressure and respiratory rate were the most important determinants of mechanical power. The respiratory rate may be the most attractive ventilator setting to adjust when targeting a lower mechanical power.

Leaf Photosynthetic and Respiratory Thermal Acclimation in Terrestrial Plants in Response to Warming: A Global Synthesis.

Leaf photosynthesis and respiration are two of the largest carbon fluxes between the atmosphere and biosphere. Although experiments examining the warming effects on photosynthetic and respiratory thermal acclimation have been widely conducted, the sensitivity of various ecosystem and vegetation types to warming remains uncertain. Here we conducted a meta-analysis on experimental observations of thermal acclimation worldwide. We found that the optimum temperature for photosynthetic rate (Topt) and the maximum rate of carboxylation of Rubisco (ToptV) in tropical forest plants increased by 0.51°C and 2.12°C per 1°C of warming, respectively. Similarly, Topt and the optimum temperature for maximum electron transport rate for RuBP regeneration (ToptJ) in temperate forest plants increased by 0.91°C and 0.15°C per 1°C of warming, respectively. However, reduced photosynthetic rates at optimum temperature (Aopt) were observed in tropical forest (17.2%) and grassland (16.5%) plants, indicating that they exhibited limited photosynthetic thermal acclimation to warming. Warming reduced respiration rate (R25) in boreal forest plants by 6.2%, suggesting that respiration can acclimate to warming. Photosynthesis and respiration of broadleaved deciduous trees may adapt to warming, as indicated by higher Aopt (7.5%) and Topt (1.08°C per 1°C of warming), but lower R25 (7.7%). We found limited photosynthetic thermal acclimation in needleleaved evergreen trees (-14.1%) and herbs (-16.3%), both associated with reduced Aopt. Respiration of needleleaved deciduous trees acclimated to warming (reduced R25 and temperature sensitivity of respiration (Q10)); however, broadleaved evergreen trees did not acclimate (increased R25). Plants in grasslands and herbaceous species displayed the weakest photosynthetic acclimation to warming, primarily due to the significant reductions in Aopt. Our global synthesis provides a comprehensive analysis of the divergent effects of warming on thermal acclimation across ecosystem and vegetation types, and provides a framework for modeling responses of vegetation carbon cycling to warming.

The effect of electronic cooling pads and Moringa oleifera supplementation from late gestation to weaning on sow production performance under heat stress conditions.

Lactating sows and their litters are particularly vulnerable to heat stress (HS). Heat stress decreases sow fertility, feed intake, milk production, and litter growth. Approaches are needed to mitigate the negative effects of HS on animal welfare and oxidative damage to tissues. The objective of this study was to measure the efficacy of conductive heat removal using electronic cooling pads (ECP) and feeding Moringa oleifera (4% of the diet, M), a feedstuff high in antioxidants, to sows from late gestation to weaning on their welfare and production performance. A study was conducted using a 2 × 2 factorial design of treatments, with mixed parity Yorkshire x Landrace sows (n=48). The sows were exposed to moderate heat stress conditions from gestation d110 to d21 of lactation. To achieve moderate heat stress, farrowing room temperature was increased incrementally daily from 25 º C to 32º C between 0800-1100 and decreased from 32º C to 26 ºC between 1700-2000. Sows were limit fed during gestation (1.36kg 2X/d) and fed ad libitum post farrowing. Treatments included HS+control corn-soybean meal based diet (HS+CS), HS+M, ECP+CS, ECP+M (n=12/treatment). Sow respiration rate (RR) and rectal temperature (RT) were measured 4-times daily (0600, 1300, 1600, 1900). The use of ECP decreased lactating sow RR (HS = 66.6 bpm, ECP = 28.3 bpm, P < 0.0001), RT (HS = 39.2 ºC, ECP =38.8 ºC, P = 0.003), and lactation BW loss (HS= -21.67kg, ECP = -5.1kg P = 0.002). ECP by time-of-day interactions (P < 0.01) existed for RR and RT, with ECP having a greater impact from 1300 to 1900, than at 0600. ECP increased lactation feed intake (P = 0.02). An ECP by diet interaction (P= 0.0004) indicated ECP increased lactation feed intake for the sows fed the CS diet (6.48kg/d vs 4.42kg/d, P = 0.0004), but did not affect feed intake of sows fed the M diet. Treatment did not affect litter weaning weight (P = 0.14). Moringa increased percent fat in milk (M=12.28%, CS =11.06%, P = 0.05). The reduction in sow RR, RT, and increased feed intake with lower loss of BW, indicate that ECP improved sow wellbeing in the HS environment. Neither ECP or M affected litter growth, despite M increasing fat content of milk and ECP-CS increasing feed intake.

Combined thrombus fragmentation and catheter-directed thrombolysis in the treatment of pulmonary thromboembolism in high- and moderate-risk patients

Introduction: In recent years with the increase in the incidence of pulmonary embolism (PE) worldwide and the rapid development of new devices in interventional cardiology, there has been a tendency to expand the indications for the endovascular treatment of acute PE. Systemic thrombolysis significantly reduces mortality in patients without contraindications for the procedure but at the cost of an increased risk of bleeding. High mortality with a conservative approach in patients with high-risk PE and contraindications for fibrinolysis, as well as moderate-risk patients with a lack of clinical response to optimal anticoagulant therapy, requires a more selective treatment approach to ensure an inevitable positive hemodynamic response. Catheter-based therapy (CBT), including mechanical thrombus fragmentation and selective thrombolysis, is a combined approach with potentially increased efficacy and safety over systemic thrombolysis. In the published literature there is a lack of sufficient data on the application of this therapeutic strategy as a first-line treatment for PE. Large, randomized trials are needed to confirm the value of CBT in these patient groups and to establish precise criteria and recommendations for the initial and follow-up monitoring during treatment. Aim: To evaluate the safety and efficacy of CBT in high- and moderate-risk patients with acute PE as an initial treatment strategy at one-year follow-up. Material and methods: For the period of May 2021- 2024, a total of 35 patients with acute PE were treated in our clinic. In this retrospective study, 23 patients were included, in which a decision was made to conduct CBT as a primary strategy, (in one case there is not a long enough follow-up at this stage). The remaining 8 patients were treated conservatively with low-molecular-weight heprain (LMWH), and the systemic thrombolysis in three of patients was administered. Demographic indicators, history of deep venous thrombosis (DVT), hemodynamic status on admission, non-invasive and invasive parameters of right ventricular burden, contraindications for fibrinolysis, fatal and non-fatal post-procedural complications were recorded. The clinical follow-up is in-hospital conditions, at 6 and 12 months in terms of mortality, manifestations of heart failure, bleeding and hospitalization for PE relapse. All patients in the study group underwent right heart catheterization according to a standardized protocol. CBT includes defragmentation of the thrombi using a Pigtail catheter and selective fibrinolysis with recombinant tissue plasminogen activator /r-TPA, alteplase/ with a dosage of 0.3 mg/kg. Results: The PESI score, which evaluates 30-day mortality in patients with acute pulmonary thromboembolism based on 11 clinical criteria, was used for risk assessment The studied cohort included patients with very high and moderately high risk and an estimated PESI score in the III-V range. CBT was technically successful in 100% (n = 23) of patients. The overall clinical success of the procedure, defined as haemodynamic stability, reversal of hypoxia, reduction of respiratory rate and improvement of peripheral perfusion was achieved in 90.4% of patients. During the hospital stay, 2 deaths were registered (8.69%), the fatal outcome being due to treatment-refractory cardiogenic shock in the first case (the patient died 24 hours after admission) (4.35%) and haemorrhagic stroke in the second (4.35%). In the remaining patients, not a single haemorrhagic incident as well as serious periprocedural complications, were detected. &amp;nbsp;The comparative analysis between echocardiography and invasively assessed pulmonary artery pressure (PAP) before and after the CBT shows that the decrease in the mean PAP (m-PAP) after the treatment is statistically significant - on average 10 mm Hg, which suggests a positive effect of the treatment. During the 6-month follow-up, two more deceased patients were registered &amp;ndash; an 81-year-old woman with previous melena before treatment for PE, and with a new episode and a large drop in haemoglobin, sent for treatment to a gastroenterology department, and a second patient with an unclear cause of death - probable sudden cardiac death (SCD). (Mortality at 6 months is 8.6%). Up to 12 months, no other adverse cardiovascular events were observed in the remaining patients. Conclusion: Our experience in endovascular therapy of acute PE showed that the methodology is both therapeutically and prognostically effective, but also low-risk for the patient. A large, randomized trial is needed before the technique can be recommended as a first-line treatment.&amp;nbsp;

Mitochondrial Genome Instability in W303-SK1 Yeast Cytoplasmic Hybrids.

Unlike most animals, some fungi, including baker's yeast, inherit mitochondrial DNA (mtDNA) from both parents. When haploid yeast cells fuse, they form a heteroplasmic zygote, whose offspring retain one or the other variant of mtDNA. Meanwhile, some mutant mtDNA (rho-), with large deletions in the nucleotide sequence, can displace wild-type (rho+) mtDNA. Consequently, offspring of zygotes with such rho- mtDNA predominantly carry the mutant variant. This phenomenon is called suppressivity. In this study, we investigated how the suppressivity of rho- mtDNA depends on the mitochondrial and nuclear genomes of the rho+ strain during crossing. Comparing two diverged laboratory strains, SK1 and W303, we measured suppressivity in crosses with four rho- strains. One rho- strain showed significantly higher suppressivity when crossed with SK1 than with W303. We then created cytoplasmic hybrids by swapping mtDNAs between these strains. Surprisingly, we found that the mtDNA of the rho+ strain, rather than its nuclear DNA, determines high suppressivity in crosses of SK1 rho+ with the rho- strain. Additionally, mtDNA replacement reduced respiration rate and growth rate on non-fermentable substrates while increasing the likelihood of functional mtDNA loss. Our data demonstrate that a mutant mtDNA variant's ability to displace another mitochondrial DNA variant in a heteroplasmic cell depends more on mtDNA sequences than on the biochemical and structural context created by the nuclear genome background.

Coral larvae increase nitrogen assimilation to stabilize algal symbiosis and combat bleaching under increased temperature.

Rising sea surface temperatures are increasingly causing breakdown in the nutritional relationship between corals and algal endosymbionts (Symbiodiniaceae), threatening the basis of coral reef ecosystems and highlighting the critical role of coral reproduction in reef maintenance. The effects of thermal stress on metabolic exchange (i.e., transfer of fixed carbon photosynthates from symbiont to host) during sensitive early life stages, however, remains understudied. We exposed symbiotic Montipora capitata coral larvae in Hawai'i to high temperature (+2.5°C for 3 days), assessed rates of photosynthesis and respiration, and used stable isotope tracing (4 mM 13C sodium bicarbonate; 4.5 h) to quantify metabolite exchange. While larvae did not show any signs of bleaching and did not experience declines in survival and settlement, metabolic depression was significant under high temperature, indicated by a 19% reduction in respiration rates, but with no change in photosynthesis. Larvae exposed to high temperature showed evidence for maintained translocation of a major photosynthate, glucose, from the symbiont, but there was reduced metabolism of glucose through central carbon metabolism (i.e., glycolysis). The larval host invested in nitrogen cycling by increasing ammonium assimilation, urea metabolism, and sequestration of nitrogen into dipeptides, a mechanism that may support the maintenance of glucose translocation under thermal stress. Host nitrogen assimilation via dipeptide synthesis appears to be used for nitrogen limitation to the Symbiodiniaceae, and we hypothesize that nitrogen limitation contributes to retention of fixed carbon by favoring photosynthate translocation to the host. Collectively, our findings indicate that although these larvae are susceptible to metabolic stress under high temperature, diverting energy to nitrogen assimilation to maintain symbiont population density, photosynthesis, and carbon translocation may allow larvae to avoid bleaching and highlights potential life stage specific metabolic responses to stress.

Conspicuous parasite modifies appearance and energetics of a marine copepod

Abstract Parasitism is an important driver of ecosystem processes. Copepods are fundamental trophic links in marine food webs and harbour many microeukaryotic parasites, but unreliable access to infected individuals limits quantitative studies of parasite infection costs. Calanus spp., (helgolandicus or finmarchicus), infected with the Yellow-Hyphal Parasite become pigmented and are found near the surface, suggesting predator-mediated dispersal. Conventional markers prevented phylogenetic inference but confirmed that the parasite is not Ichthyophonus hoferi, as previously thought. We identified the pigments, quantified the pigment content and respiration rate, and derived stable isotope signatures of infected and uninfected Calanus spp. to examine costs of infection. We found that the pigments were astaxanthin and β-carotene, associated with the host and parasite, respectively. Parasitized hosts had increased astaxanthin content, reduced respiration rate, and lower lipid content. Ultrastructure imaging revealed parasitic cells associated with lipids in the haemocoel. The changes to host phenotype have detrimental impacts on energetics and the ecology of Calanus. We discuss the role of pigments in parasite-host interactions and suggest that the parasite produces β-carotene pigment for its physiological benefits. The trade-off between physiological benefits of pigments and conspicuousness for parasites is relevant in zooplankton-host systems, as zooplankton rely heavily on transparency for survival.

Antifungal activity of 2-chloro-5-trifluoromethoxybenzeneboronic acid and inhibitory mechanisms on Geotrichum candidum from sour rot Xiaozhou mustard root tuber

Xiaozhou mustard (Brassica napiformis) root tuber, a traditional fermented vegetable, has a long history in Rongan County, Guangxi Province. However, the frequent occurrence of root tuber sour rot by Geotrichum candidum (G. candidum) has seriously reduced Xiaozhou mustard production and quality in recent years. The objective of the present study is to investigate the antifungal efficacy of 2-chloro-5-trifluoromethoxybenzeneboronic acid (Cl-F-BBA) against G. candidum and its possible mechanisms. The results revealed that a concentration of 0.25 mg/mL Cl-F-BBA completely halted mycelial growth and spore germination. Furthermore, a slightly lower concentration of 0.20 mg/mL was sufficient to compromise the integrity of the plasma membrane in mycelia and mitochondria, leading to a reduction in respiratory rate, activities of malate dehydrogenase (MDH), and succinate dehydrogenase (SDH), ATP content, and energy charge. This concentration also significantly disordered antioxidant metabolism, resulting in the accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA), and caused intracellular leakage in mycelia. In vivo experiments further demonstrated that Xiaozhou mustard root tubers treated with Cl-F-BBA exhibited markedly lower decay rates and lesion diameters compared to the control group. In summary, Cl-F-BBA presents a promising solution for controlling root tuber sour rot in Xiaozhou mustard caused by G. candidum.

Effect of edible coating of gelatin-sodium alginate with the addition of green tea (Camellia sinensis) extract on the characteristics of star fruit (Averrhoa carambola L.) during storage.

Star fruit has a good nutritional value but was very easy to damage. Edible coating can be used to extend the shelf life of star fruit. Green tea had been added to improve the mechanical properties and functional value of edible coating. This study aimed to evaluate the application of edible coating gelatin-sodium alginate with the addition of green tea to the physicochemical and microbiological characteristics of star fruit. This research was conducted by making edible coating solutions from gelatin, sodium alginate, glycerol, and green tea of various concentrations (0%, 5%, 10%, and 15%). The coating solution was applied to star fruit and stored for 1, 6, and 13 days to determine the effect of coating on the physicochemical and microbiological properties of star fruit. The results showed that adding green tea was not significantly different from the color change of the coating solution. However, there was a change in viscosity and pH along with the concentration of green tea extract (p < 0.05). FTIR analyses indicated that an interaction existed between gelatin-sodium alginate and green tea extract. The addition of green tea to star fruit with an edible coating of gelatin and sodium alginate could prevent weight loss (25.84%), reduce respiration rate (11.035mg CO2/kg/h), maintain fruit anatomy, protect against color change, inhibit pH changes (4.22), total titrated acid (0.22%), increase vitamin C (244.55mg/g), and even reduce damage for up to 13 days of storage. This study indicates that edible coating with the addition of green tea might be effective to retain the quality and extend the storage life star fruit.

Fabrication and characterization of bioactive curdlan and sodium alginate films for enhancing the shelf life of Volvariella volvacea

This study aimed to develop bioactive films based on curdlan (CD) and sodium alginate (SA) to enhance the shelf life of the Volvariella volvacea mushroom. A stable nanoemulsion of droplet size of 150.1 ± 5 nm was first formulated using 5% soy protein (Sp) and 10% lavender essential oil (LEO), achieved by ultrasound treatment for 10 min, resulting in small droplet sizes. In parallel, a CD-SA film was prepared by mixing them in a 1:1 ratio. The SpLEO nanoemulsion was then ex situ added to the CD-SA film at varying concentrations (4%, 6%, 8%, and 10%). The resulting bioactive film exhibited desirable properties, including water vapor permeability (1.15 ± 0.05 × 10−10 g m−1 Pa−1 s−1), swelling rate (547%), and tensile strength (10.1 ± 1.3 MPa). Docking and structural analyses suggested that ultrasound treatment enhanced the intermolecular hydrogen bonding, creating a uniform and regular surface and reduced crystallinity. The CD-SA film with ultrasound-treated 8% SpLEO nanoemulsion [i.e., (CD-SA/SpLEO-8)US] showed antibacterial activity against Escherichia coli and Staphylococcus aureus and extended the freshness of straw mushrooms prevention of spoilage during storage. Additionally, the film reduced respiration rate (975 mg CO₂/kg/h at 96 h) and ethylene production (160 ng/kg/s by 96 h) while effectively inhibiting straw mushroom autolysis. This led to a reduction in browning (2.91), total soluble solids (7.5%), weight loss (13.9%), and polyphenol oxidase activity (0.08 ΔOD420/min⋅g), thereby extending the shelf life of the mushrooms to 96 h. These findings highlight the potential of incorporating different molecules using ultrasound treatment to develop innovative edible films for food preservation.

Impact of pre-harvest application of 1-methylcyclopropene (1-MCP) on fruit quality, physiological disorders and respiration rate of ‘Scilate’ apple

The ethylene inhibitor 1-methylcyclopropene (1-MCP) is widely used in the apple industry as a post-harvest fumigation application to slow down the ripening process and maintain fruit quality during storage. With the development of a sprayable formulation (Harvista™, Agrofresh Inc, USA), it is becoming increasingly common in the apple industry to apply 1-MCP as a pre-harvest spray. This study investigated the impact of pre-harvest 1-MCP applied 1 week prior to harvest as a foliar application at 11.4 L ha−1 in 1000 L water, on the quality and respiration rate of ‘Scilate’ apples grown in the Huon Valley, Southern Tasmania, Australia. Two trials were undertaken, trial 1 examined fruit quality, flesh browning (FB) and fruit softening in 1-MCP treated and untreated fruit while trial 2 compared the respiration rate of 1-MCP treated and untreated fruit. Despite no effect on fresh fruit quality attributes, pre-harvest spray application of 1-MCP influenced post-harvest fruit quality, storability, and respiration rate of apples. Fruit treated with 1-MCP showed higher malic acid concentration (1.2 g L−1 vs 0.9 g L−1) and lower juice pH (4.6 vs 4.9) even after 7.5 months of regular air cold-storage along with a six-fold reduction in fruit softening in comparison to untreated fruit (2% vs 13%). Pre-harvest treatment of 1-MCP reduced respiration rate by 32%, and incidence of CO2 injury by over 40%. The incidence of radial type (senescent related) FB was reduced by 100%. A significant proportion of treated apples still suffered from severe CO2 injury. This study has demonstrated that pre-harvest application of 1-MCP to ‘Scilate’ fruit can be useful in maintaining long-term fruit quality during storage, reducing respiration rate, and lowering the incidence of FB in general. However, the risk of severe CO2 injury remains, especially with larger fruit harvested from trees with lighter crop loads.

Exploring diaphragmatic response to high-flow nasal cannula in patients with COVID-19 pneumonia using ultrasound: a proof of concept study.

Recent studies have highlighted the recognition of diaphragmatic dysfunction as a significant factor contributing to respiratory disturbances in severely ill COVID-19 patients. In the field of noninvasive respiratory support, high-flow nasal cannula (HFNC) has shown effectiveness in relieving diaphragm dysfunction. This study aims to investigate the diaphragmatic response to HFNC in patients with COVID-19 pneumonia by utilizing ultrasound. This retrospective study was conducted in a medical-surgical intensive care unit (ICU) at a tertiary care center in Buenos Aires, Argentina (Sanatorio de Los Arcos) over a 16-month period (January 2021-June 2022). The study included patients admitted to the ICU with a diagnosis of COVID-19 pneumonia who were deemed suitable candidates for HFNC therapy by the attending physician. Diaphragm ultrasound was conducted, measuring diaphragmatic excursion (DE) both before and during the utilization of HFNC for these patients. A total of 10 patients were included in the study. A statistically significant decrease in respiratory rate was observed with the use of HFNC (p = 0.02), accompanied by a significant increase in DE (p = 0.04). HFNC leads to a reduction in respiratory rate and an increase in DE as observed by ultrasound in patients with COVID-19 pneumonia, indicating promising enhancements in respiratory mechanics. However, further research is required to validate these findings.

Evidence for an adult summer diapause in mountain pine beetle (Coleoptera: Curculionidae) that varies geographically and among haplogroups.

Identifying dormancy traits is important for predicting insect population success, particularly in a changing climate that could disrupt evolved traits. The mountain pine beetle (Dendroctonus ponderosae Hopkins) is native to North America, is responsible for millions of acres of tree mortality, and is expanding northward in Canada. Research has identified thermal traits important to epidemic-phase ecology that vary among populations. Genomic research identified 3 mountain pine beetle haplogroups representing Pleistocene glacial refugia. Significant variation in generation timing aligning with the haplogroups has been observed. The adult stage was previously identified as the likely cause of differences among populations, although the mechanism(s) remain unclear. We tested for an adult summer diapause that varies among populations from 2 haplogroups, southern Colorado (CO) (central haplogroup) and southern Idaho (ID) (eastern haplogroup) using respirometry and reproduction experiments. Warm temperatures (25 °C) resulted in reduced respiration rates of central haplogroup mountain pine beetle compared to a cool temperature treatment (15 °C), whereas respiration of the eastern haplogroup did not differ between the treatments. Mated pairs of central haplogroup mountain pine beetle reared/held at 15 °C were more likely to be classified with a higher reproductive success rating compared to pairs reared/held at 25 °C. These results support a facultative summer adult diapause in southern CO central haplogroup mountain pine beetle. Manifestation of this diapause was low/absent among adults from the northerly ID location. This diapause likely serves to maintain univoltinism shown to be important for mountain pine beetle epidemic-phase ecology. The variation occurring among haplogroups highlights the long-term, evolved processes driving local adaptations in mountain pine beetle.

The Role of Modified Atmosphere Packaging in Reducing Postharvest Losses a

Modified Atmosphere Storage (MAS) and Packaging (MAP) are advanced preservation technologies widely utilized in the post-harvest handling of fruits, vegetables, and poultry products to extend shelf life, maintain quality, and reduce spoilage. These methods involve altering the atmospheric composition within storage or packaging environments, typically by reducing oxygen levels and increasing carbon dioxide concentrations. The three main gases utilized in food processing are carbon dioxide (CO2), nitrogen (N2), and oxygen (O2). The majority of fresh fruits, vegetables, and food items are made using various combinations of two or three of these gases, depending on what the demands of the particular product are. Generally, a 30–60% CO2 split is utilized for non-respiring items, where microbial growth is the primary spoiling characteristic. The remaining amount can either be pure N2 (for foods sensitive to O2) or a combination of N2 and O2. In order to minimize the respiration rate, around 5% CO2 and O2 are often employed for respiring products gas level, with N2 making up the remaining amount. This creates conditions that slow down metabolic activities, microbial growth, and oxidative reactions. For fruits and vegetables, MAS and MAP help in delaying ripening, reducing respiration rates, and maintaining texture and nutritional value. In the case of poultry products, these technologies are crucial in minimizing microbial contamination, preventing spoilage, and maintaining sensory attributes such as colour, flavour, and tenderness.

Dietary fiber source and direct-fed microbial supplementation effects on lactation performance and feeding behavior of high-producing dairy cows

The objective of this study was to evaluate the effects of dietary fiber source and direct-fed microbial supplementation on lactation performance and feeding behavior of high-producing dairy cows. Sixty-four multiparous Holstein cows (3.5 ± 1.6 [SD] lactations; 76 ± 22 DIM and 735 ± 67 kg of BW at covariate period initiation) and 32 gate feeders were enrolled in a study with a completely randomized design and a 2 × 2 factorial arrangement. Cows and gate feeders were randomly assigned to treatments (16 cows and 8 gate feeds per treatment). Cows were allowed 1 wk to acclimate to feeding gates followed by a 2-wk covariate period. During the acclimation and covariate periods, all cows were fed the same diet to meet or exceed the nutrient requirements. Following the covariate period, cows were enrolled in a 8-wk treatment period during which cows were randomly assigned to 1 of 4 treatments consisting of forage inclusion in the diet, either 45.8% (LF) or 56.7% (HF) of DM, and the supplementation of 75 mL/head per day of a direct-fed microbial (DFM) containing herbal extracts (mallow, mint, and sage), Lactiplantibacillus plantarum, Lentilactobacillus buchneri, Saccharomyces cerevisiae, and sugar cane molasses (Valibiom Mix, Valibiotics AG, Emmen, Switzerland) or without supplementation (CON). The average covariate period value of each variable was used as a covariate. Three-way interactions were observed for DMI and feed efficiency. Dry matter intake was 2 to 3 kg greater for LF-DFM than HF-CON and HF-DFM during wk 2, 3, 5, and 8 of the treatment period. Milk production was 2.1 kg/d greater for LF than HF diets. Both milk fat and MUN concentrations were greater for HF than LF diets. Conversely, milk protein concentration was lower for HF than LF diets. The respiration rate measured in the morning was lower with DFM supplementation than CON. Rectal temperature measured in the morning and averaged for the day were greater for LF than HF diets. Under the conditions of the present study, feeding high-forage diets may be an alternative for producers to reduce feeding costs depending on the price of purchased feeds. However, nonforage fiber sources (i.e., soy hulls) must be considered when producers are challenged by either forage shortages or forage with a lower nutritive value. Additionally, DFM supplementation reduced respiration rate in the morning and affected meal behavior of lactating cows.

The Shelf Life of Yellow Passion Fruit with an Edible Biocomposite Coating Based on Chitosan, Graphene Oxide Nanoparticles, and Beeswax

Yellow or sour passion fruit is a climacteric fruit with a high rate of respiration and ethylene production, and postharvest technology is needed to extend its shelf life. This study investigated the properties of a biocomposite film with chitosan (CH) incorporated with beeswax (BW) and graphene oxide (GO) nanoparticles for use as an edible coating to extend the shelf life of yellow passion fruit at 22 °C and 70% RH for eight days. CH films associated with BW showed lower water vapor permeability (WVP) than films with CH alone. However, adding GO to the CH + BW biopolymer matrix improved the WVP, decreased the solubility (12.8%), and increased the opacity of the film by 9% compared to those of the CH film. Fruits coated with CH + BW or CH + BW + GO exhibited a reduction in respiration rate, a slower ripening process by approximately 3 days, and a significant decrease in weight loss. This also resulted in a higher soluble solids content and increased antioxidative capacity of the pulp. The incorporation of GO into the CH + BW matrix resulted in a more pronounced delay of fruit ripening, as evidenced by the lower depigmentation of the peel at eight days, with a lightness approximately 10.7% lower at 54.92, a chroma value 16.5% lower at 49.33, a hue angle 7.2% higher at 92.56, a soluble solid (SS) content 16.7% higher at 11.32°Brix, and an acidity 31.9% higher at 4.18% compared to the control. Furthermore, the biopolymer packaging led to a higher consumer acceptance score for the fruit.

Addition of Mask to High-flow Nasal Oxygen: A Strategy to Improve Oxygenation in Hypoxemic Respiratory Failure Secondary to COVID-19.

High-flow nasal cannula (HFNO) reduces the need for invasive mechanical ventilation in COVID-19 patients with hypoxemic-respiratory failure. During HFNO entrainment of room air dilutes the delivered fractional inspiratory oxygen (FiO2), thereby preventing improvement in oxygenation. The placement of a mask over HFNO to improve oxygenation has provided conflicting results. We aimed to determine and compare the effect of placing various mask types over HFNO on oxygen saturation (SPO2). In this prospective physiological study 40 patients with COVID-19-associated hypoxemic respiratory failure on HFNO with O2 concentration <92% were included. The effect of placing different masks over HFNO on oxygenation, respiratory rate, heart rate, blood pressure, patient comfort, and partial pressure of carbon dioxide level (pCO2) was recorded after a prespecified time interval. We observed a significantly higher mean SPO2 and lower mean respiratory rate on using various study masks over HFNO compared to HFNO alone. On comparing various mask types, the use of N95 masks and nonrebreather (NRB) masks with O2 showed a significant increase in O2 concentration and reduction in respiratory rate compared to surgical mask (SM) and NRB without O2. The proportion of patients who achieved SPO2 of >92% was higher with the use of N95 masks (47.5%) or NRB with O2 (45%) over HFNO compared to SM (35%) and NRB without O2 (35%). No significant change was observed in heart rate, blood pressure, and CO2 level with the use of any mask over HFNO. This study demonstrates improvement in oxygenation and reduction in respiratory rate with the use of various masks over HFNO in patients of COVID-19-related hypoxemic-respiratory-failure. Significantly greater benefit was achieved with the use of N95 or NRB with O2 compared to SM or NRB without O2.

Maintaining postharvest quality and enhancing shelf-life of bell pepper (Capsicum annuum L.) using brassinosteroids: A novel approach

Bell pepper is a major vegetable crop of global commercial interest, but the postharvest quality is constrained by faster deterioration and senescence. Brassinosteroids (BRs), are an emerging and novel biomolecule that delay ripening and senescence in various vegetables. Freshly harvested bell pepper fruit were immersed in an aqueous solution of BRs concentrations (0, 2, 5, 7 and 10 μM) for 20 min and subsequently stored for 20 d at 10 ± 1°C, 85–90% RH. The bell pepper treated with 10 μM BRs significantly reduced respiration rate (∼2.3 fold), delayed weight loss (∼2.2 fold), and retained higher firmness (∼2.5 fold), total phenolic (∼1.7 fold), flavonoid (∼1.7 fold), proline (∼2 fold) and ascorbic acid content (∼2 fold) over the control fruit at the end of cold storage. Also, it retained higher DPPH radical scavenging (∼1.8 fold) and antioxidant enzyme activity (∼1.5 fold) over the control at the end of cold storage. Moreover, BRs treated bell pepper exhibited reduced malondialdehyde accumulation and delayed capsaicin, and chlorophyll degradation. Remarkably, 10 μM BRs treatment prolonged the shelf-life of bell pepper up to 20 d (10 d extra over control) without compromising quality and sensory acceptability.