Physiological Changes Research Articles

Longitudinal Assessment of Physiological Changes Following Acute COVID-19: Insights from Weeks 2, 6, and 12 After Acute Illness

Longitudinal Assessment of Physiological Changes Following Acute COVID-19: Insights from Weeks 2, 6, and 12 After Acute Illness

Flooding tolerance, biomass production, and leaf nitrogen assimilatory efficiency in 29 diverse willows (Salix spp.) genotypes during early growth

ABSTRACT Willows are frequently planted as unrooted cuttings in flood-prone areas. The occurrence of a flooding episode during the early stages of the plantation causes diverse morphological and physiological changes in willows. Thus, it is important to identify traits correlating to flooding tolerance to be used to breed genotypes with enhanced tolerance to this stress. In addition, flooding can change nitrogen absorption in plants, altering leaf nitrogen concentration. These changes could influence the photosynthetic activity, and ultimately, the growth of plantations. The aims of this work were: (i) to identify traits that increase flooding tolerance in willows during early growth and (ii) to analyze the effects of flooding on Assimilatory Nitrogen Use Efficiency (ANUE, measured as foliar biomass: foliar nitrogen concentration ratio). Two-month-old plants growing in pots of 29 willow genotypes were flooded with water covering 80% of the stem, for 43 days. At the end of this period, the flooding tolerance index (ratio between the flooded plant biomass to the non-flooded plant biomass) ranged between 39% and 103%. Flooding tolerance had a significant and positive correlation to plant height, diameter, total biomass, growth rate, leaf area, leaf number, and basic wood density. ANUE decreased in flooded plants in most genotypes, despite the increase in leaf nitrogen concentration. This implies that flooded plants were less efficient in the use of nitrogen to produce leaf biomass than the non-flooded treatment. These results are relevant for the selection of flooding tolerance in young willow plants obtained from rootless cuttings.

Unveiling the molecular dynamics of low temperature preservation in postharvest lotus seeds: a transcriptomic perspective

BackgroundPostharvest quality deterioration poses a significant challenge to the commercial value of fresh lotus seeds. Low temperature storage is widely employed as the primary method for preserving postharvest lotus seeds during storage and transportation.ResultsThis approach effectively extends the storage life of lotus seeds, resulting in distinct physiological changes compared to room temperature storage, including a notable reduction in starch, protein, H2O2, and MDA content. Here, we conducted RNA-sequencing to generate global transcriptome profiles of postharvest lotus seeds stored under room or low temperature conditions. Principal component analysis (PCA) revealed that gene expression in postharvest lotus seeds demonstrated less variability during low temperature storage in comparison to room temperature storage. A total of 14,547 differentially expressed genes (DEGs) associated with various biological processes such as starch and sucrose metabolism, energy metabolism, and plant hormone signaling response were identified. Notably, the expression levels of DEGs involved in ABA signaling were significantly suppressed in contrast to room temperature storage. Additionally, nine weighted gene co-expression network analysis (WGCNA)-based gene molecular modules were identified, providing insights into the co-expression relationship of genes during postharvest storage.ConclusionOur findings illuminate transcriptional differences in postharvest lotus seeds between room and low temperature storage, offering crucial insights into the molecular mechanisms of low temperature preservation in lotus seeds.

The difference in the photosynthetic characteristics and soil moisture of different varieties of sweet cherry (Prunus avium L.)

Sweet Cherry (Prunus avium L.) is a highly sought-after fruit in the global market due to its nutritional value and appealing sensory characteristics. This paper investigated the indicators of photosynthetic physiological characteristics and changes in soil physical properties of different varieties of sweet cherries grown in the Loess Plateau region, which strengthened the research on the ecological aspects of photosynthetic physiology of sweet cherries. By analyzing the characteristics and similarities of photosynthesis processes in different varieties, the results were obtained to showed that most of these sweet cherries showed obvious inhibition of photosynthesis at noon. The daily net photosynthetic rate (Pn) variation graph displayed a typical bimodal curve, with the lowest values occurring successively at 12:00 pm and 14:00. The Pn of sweet cherry is mainly influenced by water use efficiency (WUE) and transpiration rate (Tr). Rainier and Summit exhibited the best performance in the daily mean of Pn due to the interplay between photosynthetic physiological and ecological factors. To affect the photosynthesis of sweet cherries, covering the greenhouses with plastic film would impact the changes in light intensity and temperature. The crop management mode of uniform mulching and drip irrigation can affect the water content of different soil depths, leading to a reduction in Pn due to the varying WUE and Tr of different varieties of sweet cherries. The order of photosynthetic physiological characteristics of different varieties of sweet cherries, as revealed by principal component analysis, was as follows: Rainier > 4YJimei > 2YTieon > 4YTieon > Summit > Jimei > Tieon > Hongdeng. These results provide a scientific theoretical basis for the introduction, promote the production of sweet cherries and provide a new understanding of the plantation management mode.

Status of sexual health of married male traumatic paraplegics in Indian Population

Background: About 1.5 million individuals with spinal cord injuries (SCIs) reside in India. Sixty to seventy percent of the 20,000 new cases of SCI that is added each year are from impoverished, illiterate people. SCI leads to life-altering experiences, encompassing physical, physiological, psychological, and social changes. The sexual orientation of an individual with SCI may directly impact their self-assurance and vice versa. Aims and Objectives: Patients with SCI may have physical, physiological, psychological, and social changes, including changes in their sexuality. After a SCI, individuals’ sexual health is a crucial topic that is rarely addressed. The purpose of this study was to learn about the patients’ experiences and feelings regarding sexual activity after a SCI. Materials and Methods: Patients with SCI were given a questionnaire. This study covered all male SCI patients between the ages of 18 and 50 who were married at the time of the injury and were followed up until December 2023. The purpose of this study was to talk about different facets of sexual activity and the issues that came with it. Second, these data will support SCI sufferer’s sexual rehabilitation. Results: Of the 231 patients, 72.3% had erections but only 32% had ejaculations. 55.8% of patients experienced difficulties with sexual function as a result of other SCI sequelae, such as flexor spasm, bladder, and bowel dysfunction, among others. In response, almost 90% of patients said that they had never received sexual rehabilitation or advice on their sexuality. Conclusion: Health-care providers and clinicians do not frequently bring up sexuality with patients who have SCI. Patients who frequently inquire about sexual activity following SCI yet are seldom helped. Since there is stigma associated with the topic, every SCI clinic needs to have a specialized sexual rehabilitation staff.

Menstrual Cycle Variations in Wearable-Detected Finger Temperature and Heart Rate, But Not in Sleep Metrics, in Young and Midlife Individuals.

Most studies about the menstrual cycle are laboratory-based, in small samples, with infrequent sampling, and limited to young individuals. Here, we use wearable and diary-based data to investigate menstrual phase and age effects on finger temperature, sleep, heart rate (HR), physical activity, physical symptoms, and mood. A total of 116 healthy females, without menstrual disorders, were enrolled: 67 young (18-35 years, reproductive stage) and 53 midlife (42-55 years, late reproductive to menopause transition). Over one menstrual cycle, participants wore Oura ring Gen2 to detect finger temperature, HR, heart rate variability (root mean square of successive differences between normal heartbeats [RMSSD]), steps, and sleep. They used luteinizing hormone (LH) kits and daily rated sleep, mood, and physical symptoms. A cosinor rhythm analysis was applied to detect menstrual oscillations in temperature. The effect of menstrual cycle phase and group on all other variables was assessed using hierarchical linear models. Finger temperature followed an oscillatory trend indicative of ovulatory cycles in 96 participants. In the midlife group, the temperature rhythm's mesor was higher, but period, amplitude, and number of days between menses and acrophase were similar in both groups. In those with oscillatory temperatures, HR was lowest during menses in both groups. In the young group only, RMSSD was lower in the late-luteal phase than during menses. Overall, RMSSD was lower, and number of daily steps was higher, in the midlife group. No significant menstrual cycle changes were detected in wearable-derived or self-reported measures of sleep efficiency, duration, wake-after-sleep onset, sleep onset latency, or sleep quality. Mood positivity was higher around ovulation, and physical symptoms manifested during menses. Temperature and HR changed across the menstrual cycle; however, sleep measures remained stable in these healthy young and midlife individuals. Further work should investigate over longer periods whether individual- or cluster-specific sleep changes exist, and if a buffering mechanism protects sleep from physiological changes across the menstrual cycle.

Effects of E-Cigarettes on the Lung and Systemic Metabolome in People with HIV

The popularity of e-cigarettes (vaping) has soared, creating a public health crisis among teens and young adults. Chronic vaping can induce gut inflammation and reduce intestinal barrier function through the production of the proinflammatory molecule hydrogen sulfide (H2S). This is particularly concerning for people with HIV (PWH) as they already face impaired immune function and are at a higher risk for metabolic dysregulation, diabetes, and chronic liver disease. Furthermore, PWH experience unhealthy behaviors, making it crucial to understand the systemic metabolic dysregulation and pathophysiological mechanisms associated with vaping in this population. Here, we employed liquid chromatography–mass spectrometry (LC-MS)-based metabolomics to investigate the upper respiratory, circulation, and gut metabolic profiles of PWH who vape (n = 7) and smoke combustible tobacco/marijuana (n = 6) compared to control participants who did not vape or smoke (n = 10). This hypothesis-generating exploratory study revealed systemic alterations in purine, neurotransmitter, and vitamin B metabolisms and tissue-specific changes in inflammatory pathways and cryptic sulfur cycling associated with vaping and combustible tobacco/marijuana smoking in PWH. In addition, this study provides the first link between microbial-derived metabolite 2,3-dihydroxypropane-1-sulfonate (DHPS) and vaping/smoking (tobacco and marijuana)-induced metabolic dyshomeostasis in the gut. These findings highlight the importance of identifying the full biological and clinical significance of the physiological changes and risks associated with vaping.

Transcriptomic and physiological responses of Quercus acutissima and Quercus palustris to drought stress and rewatering

Establishment of oak seedlings, which is an important factor in forest restoration, is affected by drought that hampers the survival, growth, and development of seedlings. Therefore, it is necessary to understand how seedlings respond to and recover from water-shortage stress. We subjected seedlings of two oak species, Quercus acutissima and Quercus palustris, to drought stress for one month and then rewatered them for six days to observe physiological and genetic expression changes. Phenotypically, the growth of Q. acutissima was reduced and severe wilting and recovery failure were observed in Q. palustris after an increase in plant temperature. The two species differed in several physiological parameters during drought stress and recovery. Although the photosynthesis-related indicators did not change in Q. acutissima, they were decreased in Q. palustris. Moreover, during drought, content of soluble sugars was significantly increased in both species, but it recovered to original levels only in Q. acutissima. Malondialdehyde content increased in both the species during drought, but it did not recover in Q. palustris after rewatering. Among the antioxidant enzymes, only superoxide dismutase activity increased in Q. acutissima during drought, whereas activities of ascorbate peroxidase, catalase, and glutathione reductase increased in Q. palustris. Abscisic acid levels were increased and then maintained in Q. acutissima, but recovered to previous levels after rewatering in Q. palustris. RNA samples from the control, drought, recovery day 1, and recovery day 6 treatment groups were compared using transcriptome analysis. Q. acutissima exhibited 832 and 1076 differentially expressed genes (DEGs) related to drought response and recovery, respectively, whereas Q. palustris exhibited 3947 and 1587 DEGs, respectively under these conditions. Gene ontology enrichment of DEGs revealed “response to water,” “apoplast,” and “Protein self-association” to be common to both the species. However, in the heatmap analysis of genes related to sucrose and starch synthesis, glycolysis, antioxidants, and hormones, the two species exhibited very different transcriptome responses. Nevertheless, the levels of most DEGs returned to their pre-drought levels after rewatering. These results provide a basic foundation for understanding the physiological and genetic expression responses of oak seedlings to drought stress and recovery.

Interfacial Stresses within Droplets and Channels Influence Bacterial Physiology: A Perspective.

Bacterial cells frequently experience fluid motion in their natural environments, like water bodies, aerosols, fomites, human capillaries, etc., a phenomenon that researchers have largely overlooked. Nevertheless, some reports have suggested that the interfacial stresses caused by fluid motion inside evaporating droplets or shear flows within capillaries may trigger physiological and morphological changes in the bacterial cells. Remarkably, the virulence of bacterial cells exhibits significant alterations in response to fluctuations in stress levels and external environmental factors. The dynamics of bacterial systems are analogous to colloidal systems but with the distinction that bacterial systems exhibit responsiveness, necessitating thorough exploration in dynamic environments. In this perspective, we discuss the important issue pertaining to bacterial survival, virulence, and disease transmission. Furthermore, we delineate a pathway and underscore emerging opportunities that demand exploration to unveil new avenues in the domains of bacterial pathogenicity, drug development, and strategies for disease mitigation.

The Diagnostic Yield of Laboratory Tests in Chronic Constipation in Adults.

Chronic constipation is a common gastrointestinal complaint characterized by infrequent or difficult bowel movements, significantly affecting patients' quality of life. Laboratory markers offer potential diagnostic value in identifying physiological changes associated with chronic constipation, yet their effectiveness remains underexplored. The objective of this study was to evaluate the diagnostic value of various laboratory tests in identifying the underlying causes of chronic constipation among adults. A cross-sectional study was conducted at Kurdistan Private Hospital and Jeen Clinics in Duhok, Kurdistan, Iraq, from December 2022 to May 2024. A total of 132 patients meeting the Rome IV criteria for chronic constipation were included. Data collection involved demographic information, lifestyle factors, and laboratory tests, including complete blood count (CBC), thyroid stimulating hormone (TSH), serum calcium, serum potassium, serum glucose, serum creatinine, parathyroid hormone (PTH), and vitamin D levels. The study population consisted of 56 males (42.4%) and 76 females (57.6%) with a mean age of 46.5 years (SD=17 years) and a range of 18-81 years. Regular exercise was performed by only 56 (42.4%) patients, 85 (64.4%) patients were drinking less than 2 liters of water per day, and 108 (81.8%) were overweight or obese. Of the study population, hypothyroidism was detected in 27 (20.4%), hyperparathyroidism in 27 (20.4%), anemia in 58 (44%), leukocytosis in 24 (18.2%), renal impairment in 48 (36.4%), hypokalemia in four (3%), hyperkalemia in 12 (9.1%), hypocalcemia in 10 (7.6%), hypercalcemia in 12 (9.1%), impaired fasting glucose in 46 (34.8%), hyperglycemia in 21 (15.9%), and vitamin D deficiency in 80 (60.6%). Of the study population, 40 (30%) patients had normal laboratory investigations panel. In chronic constipation, laboratory tests have high diagnostic yield in adults and are essential for ruling out secondary causes of chronic constipation. Unhealthy lifestyles are prevalent in patients with chronic constipation.

MR Assessment of Acute Changes of Cerebral Perfusion, Metabolism, and Blood-Brain Barrier Permeability in Response to Aerobic Exercise.

It remains unclear how a single bout of exercise affects brain perfusion, oxygen metabolism, and blood-brain barrier (BBB) permeability. Addressing this unresolved issue is essential to understand the acute changes in cerebral physiology induced by aerobic exercise. To dynamically monitor the acute changes in cerebral physiology subsequent to a single aerobic exercise training session using noninvasive MRI measurements. Prospective. Twenty-three healthy participants (18-35 years, 10 females/13 males) were enrolled and divided into 10-minute exercising (N = 10) and 20-minute exercising (N = 13) groups. 3.0 T/Phase Contrast (PC) MRI (gradient echo), T2-Relaxation-Under-Spin-Tagging (TRUST) MRI (gradient echo EPI), Water-Extraction-with-Phase-Contrast-Arterial-Spin-Tagging (WEPCAST) MRI (gradient echo EPI) and T1-weighted magnetization-prepared-rapid-acquisition-of-gradient-echo (MPRAGE) (gradient echo). A baseline MR measurement plus four repeated MR measurements immediately after 10 or 20 minutes moderate running exercise. MR measurements included cerebral blood flow (CBF) as measured by PC MRI, venous oxygenation (Yv) and cerebral metabolic rate of oxygen (CMRO2) as assessed by TRUST MRI, water extraction fraction (E), and BBB permeability-surface-area product (PS) as determined by WEPCAST MRI. The time dependence of the physiological parameters was studied with a linear mixed-effect model. Additionally, pairwise t-tests comparison of the physiological parameters at each time point was conducted. A P-value of <0.05 was considered statistically significant. There was an initial drop (8.22 ± 2.60%) followed by a recovery in CBF after exercise, while Yv revealed a significant decrease (6.37 ± 0.92%), i.e., an increased oxygen extraction, and returned to baseline at later time points. CMRO2 showed a trend of increase (5.68 ± 3.04%) and a significant interaction between time and group. In addition, E increased significantly (3.86% ± 0.89) and returned to baseline level at later time points, while PS remained elevated (13.33 ± 4.79%). A single bout of moderate aerobic exercise can induce acute alterations in cerebral perfusion, metabolism, and BBB permeability. 2 TECHNICAL EFFICACY: Stage 2.

Can the reduced GH, IGF-1, and ovarian steroids concentrations be considered as suspected biomarkers of age-associated functional deficit in mares?

In humans' and experimental animals’ components of the somatotropic axis, such as growth hormone (GH) and insulin-like growth factor 1 (IGF-1) concentrations, decrease with advancing age. Although there is evidence regarding IGF-1, the effect of age on GH in mares, as well as the relationships between both parameters, have not yet been elucidated. On the other hand, although GH and IGF-1 are related to follicular development, it is unknown if they could be correlated with the circulating concentrations of ovarian steroids in mares, as occurs in other species. The hypothesis of this study was that both GH and IGF-1 could experience physiological changes with advancing age also in mares, and that both GH/IGF-1 could be correlated with oestradiol-17β (E2) and progesterone (P4), as recorded for other species. Hence, the objective of this study was to evaluate the concentrations of GH, IGF-1, E2, and P4 in mares, according to the different ages. Blood samples were drawn from 56 healthy cyclic Spanish Purebred mares belonging to four different age groups: 6–9 years, 10–13 years, 14–16 years and >16 years. Mares aged 6–9 years and 10–13 years showed higher GH concentrations (P < 0.05) than mares of 14–16 and >16 years; and mares aged 14–16 showed higher GH concentrations (P < 0.05) than >16 years (P < 0.05). Mares aged >16 years showed lower IGF-1 concentrations (P < 0.05) than mares of 6–9, 10–13 and 14–16 years (P < 0.05). The concentrations of E2 and P4 showed no significant differences among different age groups. Both GH and IGF-1 were not correlated with each other or with E2 and P4. The concentrations of E2 and P4 did not change with age. Advancing age leads to a decrease in the activity of the somatotropic axis in physiological cyclic mares, represented by a significant GH reduction, which, however, was ascribed for IGF-1 exclusively to mares over 16 years of age, without alterations in steroid hormone patterns.

Effectiveness of Motivational Interviewing and cross platform messaging application in improving oral health knowledge, attitude and behaviours among pregnant women- A Randomized Controlled Trial

Background Body goes through significant hormonal and physiological changes during pregnancy, which could be linked to changes in oral health. Many women are unaware of the negative consequences of poor dental health during and after pregnancy, both for themselves and their children. Therefore, this study aimed to assess the effectiveness of Motivational Interviewing (MI) and cross platform messaging application (WhatsApp messenger) for oral health education on the oral health knowledge, attitude and behaviours among pregnant women attending ante natal care. Methods A randomized controlled trial was conducted among 84 pregnant women. Simple random sampling was employed to select participants after oral examination. Participants were randomly allocated to two groups (Group 1: Cross-platform messaging application [WhatsApp]; Group 2: MI) using a lottery method. Pregnant women aged 18 years and older, gestational age between 8 and 30 weeks were included. A face-to-face interview and oral examination were conducted to assess baseline knowledge and oral hygiene status. A follow-up examination was conducted after one month of intervention. Inferential statistics, including the chi-square test and independent t-test, were used to compare variables between the two groups. Results The mean knowledge score at baseline was comparable between Group 1 (WhatsApp) and Group 2 (MI). However, post-intervention, Group 2 showed a significantly higher mean knowledge score compared to Group 1. Post-intervention, Group 2 exhibited a significantly better oral hygiene status compared to Group 1. Significant improvements in oral health behaviours were observed in Group 2 compared to Group 1 (p &lt; 0.001). Conclusions The findings suggested that while both interventions were effective, MI showed superior results in improving knowledge, oral hygiene status, and oral health behaviours. The personalized and client-centred approach of MI enables participants to explore and resolve ambivalence, promoting a deeper understanding of the importance of oral health during pregnancy. Registration: CTRI (CTRI/2021/09/036407, 10/09/2021).

Renal autonomic dynamics in hypertension: how can we evaluate sympathetic activity for renal denervation?

This review explores the various pathophysiological factors influencing antihypertensive effects, involving the regulation of vascular resistance, plasma volume, cardiac function, and the autonomic nervous system, emphasizing the interconnected processes regulating blood pressure (BP). The kidney's pivotal role in BP control and its potential contribution to hypertension is complicated but important to understand the effective mechanisms of renal denervation (RDN), which may be a promising treatment for resistant hypertension. Excessive stimulation of the sympathetic nervous system or the renin-angiotensin-aldosterone system (RAAS) can elevate BP through various physiological changes, contributing to chronic hypertension. Renal sympathetic efferent nerve activation leads to elevated norepinephrine levels and subsequent cascading effects on vasoconstriction, renin release, and sodium reabsorption. RDN reduces BP in resistant hypertension by potentially disrupting sensory afferent nerves, decreasing feedback activation to the central nervous system, and reducing efferent sympathetic nerve activity in the heart and other structures. RDN may also modulate central sympathetic outflow and inhibit renal renin-angiotensin system overactivation. While evidence for RDN efficacy in hypertension is increasing, accurate patient selection becomes crucial, considering complex interactions that vary among patients. This review also discusses methods to evaluate autonomic nerve activity from the golden standard to new potential examination for finding out optimization in stimulation parameters or rigorous patient selection based on appropriate biomarkers.

Effect of tributyltin exposure on the embryonic development and behavior of a molluscan model species, Lymnaea stagnalis

The presence of the organotin compound tributyltin (TBT) in aquatic ecosystems has been a serious environmental problem for decades. Although a number of studies described the negative impact of TBT on mollusks at different levels, investigations connected to its potential effects during embryogenesis have been neglected. For a better understanding of the impact of TBT on mollusks, in the present study, embryos of previously TBT-treated or not treated specimens of the great pond snail (Lymnaea stagnalis) were exposed to 100 ng L−1 TBT from egg-laying (single-cell stage) until hatching. According to our results, TBT significantly delayed hatching and caused shell malformation. TBT transiently decreased the locomotion (gliding) and also reduced the feeding activity, demonstrating for the first time that this compound can alter the behavioral patterns of molluscan embryos. The heart rate was also significantly reduced, providing further support that cardiac activity is an excellent indicator of metal pollution in molluscan species. At the histochemical level, tin was demonstrated for the first time in TBT-treated hatchlings with intensive reaction in the central nervous system, kidney, and hepatopancreas. Overall, the most notable effects were observed in treated embryos derived from TBT treated snails. Our findings indicate that TBT has detrimental effects on the development and physiological functions of Lymnaea embryos even at a sub-lethal concentration, potentially influencing their survival and fitness. Highlighting our observations, we have demonstrated previously unknown physiological changes (altered heart rate, locomotion, and feeding activity) caused by TBT, as well as visualized tin at the histochemical level in a molluscan species for the first time following TBT exposure. Further studies are in progress to reveal the cellular and molecular mechanisms underlying the physiological and behavioral changes described in the present study.

Management of Pulmonary Hypertension during Pregnancy

Abstract: Pregnancy in patients with pulmonary arterial hypertension (PAH) is a high-risk condition associated with high morbidity and mortality. Patients with severe PAH are often advised against pregnancy. Still, those patients who pursue pregnancy require a dedicated and multidisciplinary approach since the progression of fetal growth will accompany significant hemodynamic changes, which can be challenging for patients with a poorly functioning right ventricle. In this article, we describe the approach to the unique cardiovascular, respiratory, hematologic, and social challenges that pregnant patients with PAH face throughout pregnancy. We discuss the impact of these physiologic changes on diagnostic studies commonly used in PAH and how to incorporate diagnostic data in making the diagnosis and risk stratifying pregnant patients with PAH. The pharmacologic challenges of pulmonary vasodilators in pregnancy are discussed as well. Pregnant patients with PAH are at particularly high risk of mortality around the time of delivery, and we discuss the multidisciplinary approach to the management of these patients, including the use of anesthesia, inotropic support, type of delivery, and postpartum care, providing clinicians with a practical approach to the management of this difficult condition.

Morphological and Physiological Changes of Hydroponic Lettuce Grown in Varying Potassium Concentrations and an Adaptive Lighting Control System

We investigated the growth dynamics of hydroponic lettuce (Lactuca sativa) driven by the influence that potassium (K+) has on crop growth. This study aimed to determine whether increased K+ concentrations under different daily light integrals (DLIs) in a hydroponic system will boost growth of greenhouse lettuce. This study was conducted within a controlled glass greenhouse environment with varying DLIs achieved by integrating an adaptive lighting control system over a 16-hour photoperiod. We used three K+ treatments of 200, 400, or 600 mg⋅L−1 K+ and six DLI lighting treatments of 11.1, 12.9, 14.6, 15.9, 16.9, and 17 mol⋅m−2⋅d−1. We found that increasing K+ did not increase shoot dry weight, leaf area, or specific leaf area with increasing DLIs. Although K+ and DLI had an interacting effect on the root dry weight fraction, leaf chlorophyll content, and quantum yield of photosystem II, the K+ treatments did not increase or decrease with increasing DLIs. The influencing factor was DLI, which led to increases in shoot dry weight and leaf area, whereas a decrease in specific leaf area was observed with increasing DLIs. Ultimately, adding supplemental concentrations of K+ did not enhance lettuce growth, nor did these effects show any increase with increasing DLIs.

A Case of Symptomatic Bradycardia After Valve Replacement.

Editor's note: This is the next installment in a series on electrocardiogram (ECG) interpretation. Nurses in all settings should know the basics, as medications and physiological changes can cause cardiac arrhythmias. Each article will start with a brief case scenario and an ECG strip and then take you step by step through analyzing the heart rhythm.

Strategies of invasive snail Pomacea canaliculata during hibernation in rice fields of south China: effects of body size, sex, and soil depth.

The invasive freshwater snail Pomacea canaliculata is an agricultural pest with a certain level of tolerance to abiotic stress. After the harvest of late rice, the snails usually burrow themselves into the soil surface layers to overwinter and pose a renewed threatto rice production in the following year. Revealing the response of snails to environmental stresses is crucial for developing countermeasures to control their damage and spread. In this study, we conducted a 120-day in situ experiment during the winter to investigate the survival and physiological changes of hibernating snails in 0-5 and 5-10 cmsoil depths, aiming to explore their overwintering strategies. Our results showed that 73.61%, 87.50%, and 90.28% of male, female, and juvenile snails survived after hibernation for 120 days in 0-10 cm soil depth, respectively. The differences in survival rates based on sex and size of snailspotentially reflect the countermeasures of snails to rapidly reproduce after hibernation. Simultaneously, the hibernating snails exhibited the ability to maintain a certain level of body weight. During this period, the snails increased their antioxidant enzyme activities to cope with oxidative stress, and enhanced their lipid storage. The hibernation survival of snails was not significantly affected by different soil depths, indicating that they have the potential to hibernate into deeper soils. Furthermore, snails were capable of increasing their contents of bound water and glycerol to cope with sudden cold spells during hibernation. Our findings emphasize the adaptive changes of P. canaliculata snails overwintering in paddy soils. In future studies, the vulnerabilitiesof P. canaliculata during hibernation (e.g. shell characteristics, nutrient reserves, and dehydration tolerance, etc.,) should be investigated to develop effective control methods for this period. © 2024 Society of Chemical Industry.

Exposure to neonicotinoid pesticides induces physiological disorders and affects color performance and foraging behavior in goldfish.

We investigated the effects of neonicotinoid pesticides (NEOs) on the spontaneous swimming and foraging behavior, as well as the morphological and physiological changes of goldfish. Most fish reared in thiamethoxam (THM)-sprayed rice fields showed the scales easily peeled off, and increased ascites. Some individuals showed decreased bio-defense activity and low plasma Ca2+. Similar changes were found in the exposure test to THM (1.0 and 20.0 μg/L) and dinotefuran (1.2 and 23.5 μg/L). Next, the effects of a low concentration of THM (1.0 μg/L) on the spontaneous swimming and foraging behavior of fish were examined. Fish exposed to THM for 1 week became restless and had increased the swimming performance, especially under natural light, white LED lighting and blue LED lighting. Goldfish exposed to THM had also increased intake of shiny white beads under green LED illumination. These results indicate that the exposure to NEO, even for a short period and at low levels, not only suppressed bio-defense activities and metabolic abnormalities, but also stress response, the swimming and foraging behavior of the fish are likely to be significantly suffered.