Respiration Rate Research Articles

Clinical value of multiple sensors contributing to a composite heart failure ICD monitoring index

Abstract Background The HeartLogic algorithm integrates data from various implantable defibrillator (ICD) sensors to predict impending heart failure (HF) decompensation. The algorithm computes worsening in its sensors and weighs them based on a risk level. These sensors include accelerometer-based first (S1) and third (S3) heart sounds, intrathoracic impedance (TI), respiration rate (RR), the ratio of respiration rate to tidal volume (RSBI), and night heart rate (NHR). Objective This study assessed the relative worsening of ICD sensors at the onset of HeartLogic alerts, their association with patient characteristics and subsequent outcomes. Methods The HeartLogic feature was activated in 568 ICD patients (410 with CRT-D) across 26 centers, with a median follow-up of 26 months [25th–75th percentile: 16–37]. Results During the follow-up, 1200 HeartLogic alerts were recorded in 370 patients. The sensor with the highest worsening (SHW) at the alert onset was S3 (27% of alerts), followed by S3/S1 (25%), TI (16%), RR (15%), and NHR (11%), RSBI (6%). Patients with atrial fibrillation (AF) at implantation and those with chronic kidney disease (CKD) had higher alert prevalence (AF 84% vs. no-AF 58%, CKD 72% vs. no-CKD 59%; both p <0.05) and higher alert rates (AF 1.51/patient-year vs. no-AF 0.88/patient-year, CKD 1.30/patient-year vs. no-CKD 0.89/patient-year; both p <0.05). AF patients had alerts with every sensor as SHW, while CKD patients had alerts primarily with TI, RR, and RSBI as SHW (Figure). In 85% of cases among 247 patients with >1 alert, the SHW changed between successive alerts. Of the 88 (7%) alerts resulting in HF hospitalizations or deaths, a greater proportion featured RR or RSBI (11%) and NHR (11%) as SHW, followed by heart sounds (5%) (both p <0.05). Clinical events were more common with the first alert (12.6%) than subsequent alerts (5.2%, p <0.001). Conclusion HeartLogic alerts are predominantly associated with the highest worsening in heart sounds. Nevertheless, recurrent alerts often involve other sensors, suggesting varied HF progression mechanisms and potential divergent outcomes. The frequency of alerts and the pattern of worsening in ICD sensors are linked to patient characteristics.

The cardioprotective potential of soluble urokinase Plasminogen Activator Receptor (suPAR) in myocardial ischemia

Abstract Background and aims: Increased circulating soluble urokinase plasminogen activator receptor (suPAR) levels are associated with adverse cardiovascular outcomes, however, any cardiovascular-related functions remain unknown. This study aimed to (i) document haemodynamic profiles in isolated rat hearts under the influence of suPAR, and to (ii) explore any mechanisms triggered by suPAR following myocardial ischaemia-reperfusion. Methods We undertook a 4-pronged approach (Figure 1). A Langendorff isolated rat heart model was used to perfuse all hearts with Krebs-Henseleit solution flowing retrogradely through the aorta at 37°C. A balloon inserted into the left ventricle allowed measurements of ventricular pressure, and a pressure transducer placed above the aorta recorded perfusion pressure for coronary flow rates. The experimental protocol consisted an initial 30-minute stabilisation period, followed by 40 minutes of ischemia via buffer flow cessation. Hearts were subsequently recovered during 90 minutes of reperfusion, receiving either suPAR treatment or perfusion buffer as controls. An inhibitor arm comprising co-infusion of suPAR and a monoclonal antibody capable of binding to suPAR was also assessed. Troponin T was measured in outflow perfusates collected at specific intervals. Proteins from hearts in treatment groups were separated using gel electrophoresis, with Western blotting to visualise the phosphorylation status of kinases (Akt, STAT). High-flow respirometry and fluorometry were investigated in cardiac mitochondria to determine respiration rates and ATP production in ischaemia reperfusion under the influence of suPAR. Statistical analysis was conducted with ANOVA using SPSS. Results Hearts receiving suPAR infusion at reperfusion (n = 16) showed a significant increase in developed pressure (p = .017) and lower perfusion pressure (p = .02) compared to controls (n = 16), revealing that suPAR-treated hearts recovered with better contractility and vasodilatory properties post-ischaemia. suPAR’s haemodynamic profiles in the antibody group were similar to controls, attenuating suPAR-induced effects (n = 8). Outflow effluents in suPAR-treated hearts obtained >3 fold lower serial Troponin T values than controls (p < .001). Heart tissues receiving suPAR treatment revealed a 1.7-fold increase in Akt (p = .001) and a 3.8-fold increase in STAT3 phosphorylation compared to controls (p < .001) and the inhibitor group (p = .04). Finally, suPAR increased mitochondrial ATP production by 28% (p = .013) compared to controls after ischaemia. Conclusion This is a world-first demonstration of suPAR’s cardioprotective influences in isolated rat hearts recovering from ischaemia. suPAR’s ability to promote cardiac contractility and vasodilation was associated with lesser injury as shown by Troponin T reduction. Mechanistically, suPAR infusion upregulated two key cardioprotective pathways, which may also function to protect cardiac mitochondria.Figure 1 - Schematic of Methods

ND-13 preserves mitochondrial integrity via the RhoA/ROCK1/Drp1-S616 pathway providing acute cardioprotection in myocardial infarction

Abstract Background Ischemia-reperfusion injury (IRI) following acute myocardial infarction is a major contributor to heart failure and mortality worldwide. Drp1-driven mitochondrial fragmentation disrupts mitochondrial function, increases cardiomyocyte death, and aggravates cardiac dysfunction. We investigated whether ND-13, a novel DJ-1-derived peptide, can acutely protect the heart by maintaining mitochondrial homeostasis and modulating Drp1 activity during IRI. Methods The effects of ND-13 on Drp1 activity were assessed by studying mitochondrial dynamics, function and survival signalling pathways. Cardioprotective effects of ND-13 were assessed using in vitro, ex vivo and in vivo models of IRI. Results ND-13 demonstrated acute cardioprotective effects in murine adult cardiomyocytes subjected to simulated IRI by a 42% reduction in cell death. The excessive mitochondrial fission following IRI was attenuated by inhibiting Drp1 phosphorylation at the Ser616 residue by reduced activity of the RhoA/ROCK1 pathway. This in turn enhanced mitochondrial function as seen through increased mitochondrial respiration rates (basal, maximal and spare respiratory capacity), increased ATP production, maintained mitochondrial membrane potential and reduced reactive oxygen species levels. The acute cardioprotective effect of ND-13 was reproduced in both an ex vivo Langendorff based model of IRI with a 43% reduction infarct size and an in vivo murine model of IRI with a 35% reduction of infarct size. These results indicate the robust effect of the peptide and its potential for clinical translation through intravenous delivery. Conclusion In this study, we demonstrate ND-13 as a small peptide that modulates mitochondrial dynamics through the RhoA/ROCK1/DRP1-S616 pathway, which highlights a potential new therapeutic target for myocardial IRI.

Dynamic Characteristics of Soil Respiration in Park Green Spaces in Qingdao City

Urban green spaces play an essential role in maintaining the carbon cycle and mitigating climate change in urban ecosystems. In order to gain more carbon sinks from urban green ecosystems, it is essential to determine the carbon sequestration statuses and soil respiration rates of dominant green spaces, especially park green spaces. However, in comparison to natural ecosystems, the dynamic characteristics of soil respiration in artificial park green spaces remain unclear. This study investigated the soil respiration rates for three forest communities (dominated by Prunus serrulata var. lannesiana, Cedrus deodara, Ginkgo biloba, respectively), a shrub community (dominated by Aucuba japonica var. variegata) and a lawn community (dominated by Poa pratensis) in the Qingdao Olympic Sculpture and Culture Park. We used the CRIAS-3 portable photosynthesis system in combination with the SRC-1 soil respiration chamber to measure the soil respiration rate from July 2022 to June 2023 and analyzed the dynamic variations in the soil respiration rate for these specific plant communities. Our results showed that the diurnal variation in soil respiration presented a unimodal curve for the five plant communities, and it peaked at midday or in the early afternoon. They also exhibited a significant seasonal difference in the soil respiration rate, which was characterized by higher rates in summer and lower rates in winter. The lawn community exhibited significantly higher soil respiration rates compared to the woody plant community. The mean annual soil respiration rate (RS) was, respectively, 2.88 ± 0.49 µmol·m−2·s−1, 1.94 ± 0.31 µmol·m−2·s−1, 1.43 ± 0.21 µmol·m−2·s−1, 1.24 ± 0.14 µmol·m−2·s−1 and 1.05 ± 0.11 µmol·m−2·s−1 for the lawn community, Ginkgo biloba community, Prunus serrulata var. lannesiana community, shrub community and Cedrus deodara community. The soil temperature at a 10 cm depth (T10) accounted for 67.39–86.76% of the variation in the soil respiration rate, while the soil volumetric water content at a 5 cm depth (W5) accounted for 9.29–44.01% of the variation for the five plant communities. The explained variance for both T10 and W5 ranged from 67.8% to 87.6% for the five plant communities. The Q10 values for the five different communities ranged from 1.97 to 2.75. Based on these findings, this paper concludes that the factors influencing the soil respiration process in urban green spaces are more complicated in comparison to natural ecosystems, and it is essential to comprehensively analyze these driving factors and key controlling factors of soil respiration across urban green spaces in future studies.

Feasibility of Using Wearable Sensors to Measure Listening-Related Stress

Purpose: This study evaluated the feasibility of using wearable sensors to assess listening-related stress in varying listening difficulties. The results were compared to listening effort assessed using laboratory-grade physiological measures. We hypothesized that these wearable sensors could accurately measure listening-related stress and that the results would be in the same direction as those observed with laboratory-grade equipment. Method: A within-subject repeated-measures study was conducted on 16 young adults with typical hearing ability. Participants wore three commercially available sensors to record heart rate (HR), respiration rate (RR), and galvanic skin response (GSR). Participants' listening-related stress was assessed using self-report, wearable sensors, and laboratory-grade physiological measures while listening to sentences in noise. Listening conditions were manipulated in terms of signal-to-noise ratios (SNRs; −4, 0, +4, and +8 dB SNR), sentence predictability (high and low), and stress-inducing negative feedback (flash of light and monetary punishers). Results: On average, participants reported higher arousal and task load with decreasing SNR, for low predictability, and with negative feedback. Participants had significantly higher HR and RR in difficult listening conditions, when measured with wearable sensors. However, no significant differences were observed for skin conductance. There was a good agreement between the measures for HR but not for RR and GSR. Conclusions: Although wearable sensors have potential in reflecting changes in listening effort, the results were not consistent with laboratory-grade measures. Methodological choices in both measures and design appear to affect outcomes. Future studies should focus on crafting designs appropriate to wearable devices to reflect changes in listening-related stress.

Procurement and Preservation of Neonatal Porcine Cardiac Tissue.

The porcine and human heart are remarkably similar in cardiac physiology and biochemistry. Translational research involving the porcine biomedical model is becoming increasingly applicable for the study of human cardiac function in health and disease. Presently, few protocols exist for collecting experimentally viable cardiac tissue from large animal models, particularly during neonatal maturation. To address this deficiency, we have developed a technique to procure and preserve ventricular tissue from neonatal piglets at day 3 (n=4) and day 30 (n=6) post-partum. Piglets were subjected to a strict sedation, anesthesia, and analgesia regimen. During surgery, cardiopulmonary indices of electrocardiogram, heart rate, systolic and diastolic blood pressure, respiration rate, peripheral O2 saturation, and end-tidal CO2 were monitored continuously to ensure normal cardiac function. Prior to cardiectomy, each heart was perfused with an intravenous administration of heparin (10 ml/kg) and ice-cold Custodiol HTK cardioplegia solution (10 ml/kg). After cardiac explantation, myocardial samples (dimensions: 1 x 1 x 1 cm) were dissected from the left and right ventricles and snap-frozen in liquid nitrogen. Analysis via SDS-PAGE and densitometry demonstrated that myofibrillar proteins are stable and undegraded. Western Blots showed full expression of protein. These results suggest that the detailed cardiac tissue procurement technique preserves the experimental viability of the cardiac tissue and prevents the degradation of myofibrillar proteins.

Organic carbon decomposition temperature sensitivity positively correlates with the relative abundance of copiotrophic microbial taxa in cropland soils

Revealing the relationships between the temperature sensitivity of soil organic matter decomposition (Q10) and microbial communities is critical to predict ecosystem feedbacks to global warming. However, the relationships are still far from well understood, especially within the low latitude regions. To address this knowledge gap, soil samples were collected from >100 cropland sites in Southwest China, a region with highly diverse climatic and environmental conditions. The results showed that Q10 values substantially varied across the region, ranging from 1.85 to 6.81, with an average value of 3.27. They were significantly positively correlated with the contents of soil organic carbon, while negatively correlated with the ratios of soil dissolved organic carbon to total organic carbon content. This indicates that soils with high organic carbon contents are more vulnerable to global warming. Further analysis suggested that Q10 values were positively correlated with soil microbial respiration rates, fungal abundance, prokaryotic diversity, and the relative abundance of copiotrophic microbial lineages, but negatively correlated with the proportions of oligotrophic microbes and microbial co-occurrence network degree. The structural equation modeling analysis suggested that soil organic carbon and its quality, as well as microbial attributes were the main factors explaining the variation in Q10 values. The findings in this study highlight the crucial and complex roles of soil microbiome in determining ecosystem feedbacks to global warming.

Epidemiological Aspects, Clinicopathology, Hemato-biochemistry and Therapeutic Management of Viperine Snake Envenomation in Buffaloes (Bubalus bubalis)

Background: Poisonous snakebite is a neglected tropical disease, frequently reported in animals including buffaloes. Snakebites are responsible for considerable morbidity and mortality in animals causing economic losses to dairy farmers. Methods: To establish the baseline data of epidemiology, clinical syndrome, hemato-biochemistry and diagnosis of viper snakebites and to standardize the treatment of viper snakebite in buffaloes. Result: The highest incidence of viper envenomation was observed during the monsoon and post-monsoon season in female buffaloes above 4 years of age. The clinical signs such as tachycardia, increased respiration rate, ascending swelling of affected limbs, asymmetrical swelling with dyspnea in case of bite over face and bleeding at the site of bite were observed in envenomed buffaloes. Hemato-biochemical analysis revealed neutrophilic leukocytosis, thrombocytopenia, prolonged capillary blood clotting time, elevated values of blood urea nitrogen (BUN) and creatinine. Post-mortem examination showed hemorrhages and blood-stained serous fluid in subcutaneous tissue and skeletal muscles of the affected limbs. The histopathological changes such as extensive myonecrosis and hemorrhages with marked edema in skeletal muscles, widespread interstitial and intra-alveolar hemorrhages and fibrinous microthrombi in pulmonary vasculature, multifocal to coalescing areas of massive hemorrhages and coagulative necrosis within hepatic parenchyma and marked degeneration of renal tubular epithelium were evident. Therapeutic regimen consisting of polyvalent anti-snake venom, with antibiotics, diuretics, vitamin B complex, styptics, fluids and corticosteroids in non-pregnant while non-steroidal anti-inflammatory drugs in pregnant buffaloes was used. The present treatment strategy showed subsidence of clinical signs, restoration of platelet count, blood clotting time, urea nitrogen and creatinine values depicting clinical recovery with 88.15% survival rate in treated buffaloes.

Plant Photosynthetic and Respiration Rates Are Key Populational Traits to Improve Yield and Quality for Good-Tasting Double-Cropped Rice

Improving the yield and quality for tasty rice varieties is a great challenge. In the present study, different nitrogen rates and plant density were utilized to form differential rice populational structures, which were determined to clarify key traits determining grain yield and quality for tasty rice varieties in a double-cropped rice system in subtropical China. The present results showed that the plant photosynthetic rate, leaf area index and plant respiration rate had important and significant impacts on the grain yields of both early and late rice, though the late rice yield was also significantly affected by the canopy temperature. In addition, among the studied populational traits, plant photosynthetic and/or respiration rates had significant effects on all quality traits. Consistently, grain yield and quality were significantly improved with the increasing plant photosynthetic and respiration rates through correlative analysis, which was also observed in principal components analysis. Overall, the present study suggests that both the grain yield and milling and appearance qualities could be improved through the optimal management of nitrogen and plant density through increasing plant photosynthetic and respiration rates.

Developing an Active Biodegradable Bio-Based Equilibrium Modified Atmosphere Packaging Containing a Carvacrol-Emitting Sachet for Cherry Tomatoes

This study aimed to develop an active biodegradable bio-based (polylactic acid/PLA) equilibrium modified atmosphere packaging (EMAP) containing a carvacrol-emitting sachet (created by poly-hydroxybutyrate) (PLA-PHB-CARV) to extend the shelf-life of cherry tomatoes at 15°C and 25 °C. Cherry tomatoes in macro-perforated polypropylene (PP) films (mimicking the commercial packaging) or in PLA-based micro-perforated film without the carvacrol sachet (PLA) were also tested. Weight loss, decay, headspace gases, pH, titratable acidity (TA), total suspended solids (TSS), ripening index, color, texture, total viable counts (TVC), and sensory analysis were performed. Decay was 40% in PLA-PHB-CARV, and 97% in PP after 20 days at 25 °C. PLA-PHB-CARV showed lower weight loss (p < 0.05) and stable firmness compared to PP and PLA at both temperatures. TSS and TA were not affected by the packaging at 15 °C, while at 25 °C, the TSS accumulation was inhibited in PLA-PHB-CARV compared to in PLA and PP (p < 0.05), indicating a notable delay in the ripening process. PLA-PHB-CARV retained their red color during storage compared to PP and PLA. Carvacrol addition inhibited TVC compared to PP and PLA by ca. 2.0 log CFU/g during storage at 25 °C, while at 15 °C, the packaging did not reveal a significant effect. Overall, the results indicated that the developed active EMAP may be adequately used as an advanced and alternative packaging for tomatoes or potentially other fruits with a similar respiration rate versus their conventional packaging, showing several advantages, e.g., a reduction in petrochemical-based plastics use, shelf-life extension of the packaged food, and consequently, the perspective of limiting food waste during distribution and retail or domestic storage.

PINK1-Mediated Mitochondrial Activity Confers Olaparib Resistance in Prostate Cancer Cells.

Olaparib, a PARP inhibitor, is a targeted therapy used in treating various cancers including castration-resistant prostate cancer (CRPC). Despite its efficacy, resistance to Olaparib remains a significant challenge. Understanding the molecular mechanisms underpinning this resistance is crucial for developing more effective treatment strategies. This study focuses on elucidating the role of mitochondrial alterations and the PINK1 gene in conferring Olaparib resistance in CRPC cells. We investigated the transcriptomic and functional differences in mitochondrial activity between Olaparib-resistant (2B-OlapR, LN-OlapR) and treatment naïve prostate cancer (PCa) cells (C4-2B, LNCaP) in both castration sentitive and resistant settings. Through RNA sequencing and Gene Set Enrichment Analysis (GSEA), we identified significant enrichment of mitochondrial and oxidative phosphorylation-related gene sets in Olaparib Resistant derived cell lines. Resistant lines exhibited enhanced mitochondrial functionality including increased basal and maximal respiration rates, as well as elevated ATP production and spare respiratory capacity compared to parental cells. Subsequent investigations revealed a substantial increase in mitochondrial mass and electron transport chain complex I activity in Olaparib-resistant cells. Furthermore, overexpression of the PINK1 gene was observed in resistant cells, which was correlated with resistance to Olaparib and poor clinical outcomes in prostate cancer patients. Inhibition of PINK1 expression significantly reduced mitochondrial function and mass, impaired cell growth, and decreased resistance to Olaparib. These findings suggest that PINK1 plays a crucial role in modulating mitochondrial dynamics that confer therapeutic resistance, highlighting its potential as a therapeutic target for overcoming Olaparib resistance in PCa.

Chemotherapy effects on mitochondrial function in adipose tissue in oesophageal and gastroesophageal junction adenocarcinomas with or without associated cachexia: protocol for a prospective, comparative observational study (ChiFMeOE)

IntroductionCachexia is strongly associated with digestive cancers, particularly oesogastric cancer. Mitochondria in adipose tissue are involved in the regulation of metabolism and physiopathology of cancer cachexia in animal studies. Chemotherapeutic...

Microbiological and Haemato-biochemical Studies in Canine Pyometra

Background: Canine pyometra, is a pathological condition that results in the accumulation of purulent exudate in the uterus due to hormonal imbalance in female dogs. This is the most prevalent hormonally mediated reproductive disorder and life threatening disease of intact female dogs. The objective of the present study was to assess the physiological, haematological and biochemical changes and isolate the pathogenic microorganism present in the uterus of pyometra bitches. Methods: This study was carried out in ten bitches with a history of lethargy, depression, in appetence, polydipsia, occasional vomiting and vaginal discharge presented for treatment at the Veterinary Poly Clinic, Coimbatore, Tamil Nadu. The disease was diagnosed by history, clinical signs, physical examination, imaging techniques haematology and biochemical study. The involvement of the pathogenic organism was confirmed by microbial examination of the pus-filled uterus after the ovariohysterectomy. Result: The result showed that physiological parameters rectal temperature, heart rate and respiration rate were increased in pyometra affected dog than healthy one. The haematological parameters of red blood cell count, haemoglobin and packed cell volume were decreased in pyometra affected dogs than healthy dogs. Leukocytosis, neutrophilia, lymphocytosis, monocytosis and eosinophilia condition also observed in pyometra affected dogs. Biochemically, increased Blood urea nitrogen (BUN) creatinine and hyperprotenimia were observed in pyometra dogs. Increased activity of hepatic enzyme Alanine transaminase (ALT), Aspartate aminotransferase (AST) and Alkaline phosphatase (ALP) were also observed in pyometra dogs. The major pathogenic microorganisms involved in pyometra are Escherichia coli (40.25%), Staphylococcus (20.46%), Streptococcus (20.32%), Pseudomonas (6.41%), Proteus (6.32%) and Pasteurella (6.24%). Thus the dogs with pyometra show significant changes in physiological, haematological, biochemical parameters and growth of pathogenic microorganism in uterine fluid were the important indications of pyometra affected dogs.

Vital signs detection of moving targets using FMCW radar

Abstract Respiratory and heartbeat rates are crucial indicators for human health assessment. Compared to contact-based measurements, millimeter-wave radar detection of these vital signs avoids the discomfort caused by physical contact and better protects personal privacy, making it highly valuable for home health monitoring. The use of millimeter-wave radar for vital sign detection of the human body is mostly focused on targets in a stationary state at present. However, the human body may sway or even move during actual detection. This article proposes a non-contact vital sign detection method for moving targets. Compared with methods for detecting vital signs of stationary targets, detecting vital signs of moving targets requires determining the range bin where the targets are located continuously and extracting target phase information. The noise components such as movement and sway contained in the phase signal need to be removed. In this paper, moving target indication is used to remove static components, an adaptive range bin selection method is proposed to determine the range bin where the targets are located, and range bin selection fluctuation is smoothed using a moving average filter. The wavelet transform is used to decompose the phase signal, remove swaying noise based on autocorrelation function, and reconstruct the life signal for different scale factors. A bandpass filter is used to separate the respiratory and heartbeat signals, and a notch filter is designed to suppress respiratory harmonic signals. The experimental results show that the proposed method can separate vital signs signals from the phase signals of moving targets, achieving detection of respiration and heartbeat rate. The average accuracy of respiration and heartbeat rate detection is 94.7% and 95.5%, respectively.

The effect of aeration and irrigation on the improvement of soil environment and yield in dryland maize

The aim of this study was to examine the effect of long-term aerated seepage irrigation technology on soil fertility changes and maize yield under continuous maize cropping system in red loam soil, and to explain the mechanism of maize yield increase under this technology, which can provide theoretical basis for crop quality improvement and yield increase under aerated irrigation (AI) technology. Therefore, this research was conducted for four field seasons in 2020–2023 at the National Soil Quality Observation Experimental Station, Zhanjiang, China. Soil aeration, soil fertility, root growth, physiological traits, and yield indicators were evaluated by conventional underground drip irrigation (CK) and AI. Our results showed that AI treatment significantly improved soil aeration and soil fertility. Increases in soil oxygen content, soil respiration rate, soil bacterial biomass, and soil urease activity were observed, corresponding to increases from 3.08% to 21.34%, 1.90% to 24.71%, 26.37% to 0.09%, and 12.35% to 100.96%, respectively. The effect of AI on maize indicators increased year by year. Based on improvements in soil aeration and fertility, root length, root surface area, and root dry weight under AI treatment were enhanced by 15.56% to 53.79%, 30.13% to 62.31%, and 19.23% to 35.64% (p < 0.05) compared to the CK group. In addition, maize agronomic traits and physiological characteristics showed improved performance; in particular, over 1.16% to 14.42% increases were identified in maize yield by AI treatment. Further analysis using a structural equation model (SEM) demonstrated that the AI technology significantly promotes the improvement of root indicators by enhancing soil aeration and soil fertility. As a result, maize yield could be increased significantly and indirectly

Thinning-induced decrease in fine root biomass, but not other fine root traits in global forests

In forest ecosystems, changes in the expression of tree absorptive root traits following management interventions are expected to influence post-thinning forest structure and function. Fine root traits are expected to be especially responsive to forest thinning—one of the most common forest management interventions and the focus of our research here—influencing tree-level responses to environmental change, and thereby contributing to post-thinning stand-level dynamics and ecosystem processes. However, there remains limited understanding surrounding whether or not forest thinning influences the expression of root morphological, chemical, and physiological traits associated with belowground resource acquisition. We conducted a global meta-analysis to evaluate the response of 13 fine root traits to forest thinning. Our study included analysis of 769 paired observations of root traits values pre- and post-thinning, derived from 89 peer-reviewed publications. Our meta-analysis found that forest thinning leads to a decrease in fine root biomass by 11.7% on average, while other root traits including fine root length, root C and N concentrations, root lifespan, and root respiration rates, are largely unresponsive to thinning treatments. Thinning tended to reduce fine root biomass at early stand recovery stages, with increases in fine root biomass being detected at later seral stages, especially in heavy thinning experiments. The effect of thinning on fine root biomass was most pronounced in deeper soil horizons. The influence of thinning on fine root trait expression was not affected by ecosystem or stand type, with the exception of biomass which decreased in temperate and coniferous forests. Our results demonstrate variations of fine root traits to forest management, as well as the importance of stand recovery time and thinning intensity in regulating fine root trait expression in retention trees. These patterns may have strong implications for governing soil carbon stocks in managed forests associated with decreased root inputs into deeper soils. Overall, our findings can enhance our comprehension of how forest management affects fine root trait expression, and relationship between managed forests and belowground ecosystem structure and function.

Dispersal of microbes from grassland fire smoke to soils.

Wildland fire is increasingly recognized as a driver of bioaerosol emissions, but the effects that smoke-emitted microbes have on the diversity and community assembly patterns of the habitats where they are deposited remain unknown. In this study, we examined whether microbes aerosolized by biomass burning smoke detectably impact the composition and function of soil sinks using lab-based mesocosm experiments. Soils either containing the native microbial community or presterilized by γ-irradiation were inundated with various doses of smoke from native tallgrass prairie grasses. Smoke-inundated, γ-irradiated soils exhibited significantly higher respiration rates than both smoke-inundated, native soils and γ-irradiated soils exposed to ambient air only. Microbial communities in γ-irradiated soils were significantly different between smoke-treated and control soils, which supports the hypothesis that wildland fire smoke can act as a dispersal agent. Community compositions differed based on smoke dose, incubation time, and soil type. Concentrations of phosphate and microbial biomass carbon and nitrogen together with pH were significant predictors of community composition. Source tracking analysis attributed smoke as contributing nearly 30% of the taxa found in smoke-inundated, γ-irradiated soils, suggesting smoke may play a role in the recovery of microbial communities in similar damaged soils. Our findings demonstrate that short-distance microbial dispersal by biomass burning smoke can influence the assembly processes of microbial communities in soils and has implications for a broad range of fields including agriculture, restoration, plant disease, and biodiversity.

Hydrogen Sulfide Modulates Astrocytic Toxicity in Mouse Spinal Cord Cultures: Implications for Amyotrophic Lateral Sclerosis.

Hydrogen sulfide (H2S), a known inhibitor of the electron transport chain, is endogenously produced in the periphery as well as in the central nervous system, where is mainly generated by glial cells. It affects, as a cellular signaling molecule, many different biochemical processes. In the central nervous system, depending on its concentration, it can be protective or damaging to neurons. In the study, we have demonstrated, in a primary mouse spinal cord cultures, that it is particularly harmful to motor neurons, is produced by glial cells, and is stimulated by inflammation. However, its role on glial cells, especially astrocytes, is still under-investigated. The present study was designed to evaluate the impact of H2S on astrocytes and their phenotypic heterogeneity, together with the functionality and homeostasis of mitochondria in primary spinal cord cultures. We found that H2S modulates astrocytes' morphological changes and their phenotypic transformation, exerts toxic properties by decreasing ATP production and the mitochondrial respiration rate, disturbs mitochondrial depolarization, and alters the energetic metabolism. These results further support the hypothesis that H2S is a toxic mediator, mainly released by astrocytes, possibly acting as an autocrine factor toward astrocytes, and probably involved in the non-cell autonomous mechanisms leading to motor neuron death.

Effects of Temperature and Packaging Atmosphere on Shelf Life, Biochemical, and Sensory Attributes of Glasswort (Salicornia europaea L.) Grown Hydroponically at Different Salinity Levels.

Halophytes, such as Salicornia species, are promising new foods and are consumed for their pleasant salty taste and nutritional value. Since Salicornia is perishable, modified atmospheric packaging (MAP) can be a useful tool, in combination with proper temperature, to halt further quality degradation in this type of product. The purpose of this study was to investigate the effect of MAP, with or without refrigeration, to extend the shelf life of glasswort (Salicornia europaea L.) grown hydroponically (floating raft system) in a greenhouse with a nutrient solution containing 0 g/L (C) or 12.5 g/L of NaCl (T). The dry matter content, weight loss, respiration rate, biochemical composition, color, antioxidant capacity, and sensorial attributes were determined in shoots after harvest and during storage in plastic bags filled with technical air or with MAP at 4 or 20 °C for 120 h. At harvest, plants supplied with salt-enriched solution (T) showed a significant improvement in nutritional value and sensory profile. Storage in air at room temperature (20 °C) accelerated weight loss and diminished color stability, particularly in non-salinity samples (C), while MAP extended the shelf life of all the samples regardless of the storage temperature adopted. Optimal storage conditions were observed when MAP was combined with refrigeration, which allowed to effectively preserve shoots sensory acceptability for a period of about seven days. Future research could further explore the long-term effects on the nutritional value and sensory quality of S. europaea under various combinations of MAP and different storage temperatures ranging between 4 °C and 20 °C.

Extending Raspberry Shelf Life and Maintaining Postharvest Quality with CO2 Atmospheres

Raspberry (Rubus idaeus L.) fruit are known for their extremely short shelf life. Decay, leakiness, and loss of firmness are the most common limiting factors contributing to their short storage life. However, storage in elevated CO2 and reduced O2 atmospheres can delay senescence in fruit by reducing softening, respiration and ethylene production rates, and pathogen growth. In this study, raspberries were exposed to four different CO2 atmospheres—15 kPa CO2 and 6 kPa O2 (15 kPa); 8 kPa CO2 and 13 kPa O2 (8 kPa); 5 kPa CO2 and 16 kPa O2 (5 kPa); or 0.03 kPa CO2 and 21 kPa O2 (0.03 kPa)—and were evaluated for their postharvest quality periodically during two weeks of storage in 2020 and 2021. Raspberry fruits kept in a 15 kPa CO2 atmosphere followed by 8 kPa CO2 had higher firmness, brighter red color, and the least fungal decay or leakiness. In all atmospheres, the total anthocyanin content increased over time, although the rate of increase was slowed by high CO2. The raspberries’ visual attributes deteriorated over time in all atmospheres, but high CO2 atmospheres slowed the rate of deterioration. After five days, the quality of air-stored raspberries was significantly degraded, while the raspberries stored in elevated CO2 maintained good quality for up to ten days.