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Effects of personality, perceptual difficulty and pacing of a task on productivity, job satisfaction, and physiological stress.

The relative psychological, physiological, and performance advantages and disadvantages of utilizing machine-paced and self-paced work were examined by having 12 subjects perform a marking-stapling task at 2 levels of perceptual difficulty and under 2 pacing conditions for 30 min. each. (a) 3 subjects who on the personality tests were identified as introverted, reserved, and trusting preferred to work in the machine-paced condition, while 9 subjects who were identified as extroverted, outgoing and suspicious preferred the self-paced condition, (b) the performance errors in machine-paced operation were 372% higher than for self-paced work, and (c) there were no differences between machine-paced and self-paced work on physiological variables, except for sinus arrhythmia for the task with high perceptual load, and quantity of production.

Achievement

Microbial partnerships and molecular mechanisms in plant stress physiology for climate-resilient and sustainable farming.

Plant-microbial partnerships and their underlying molecular mechanisms are indispensable, natural drivers of improved nutrient acquisition and stress tolerance in the face of climate-driven environmental challenges. Modern multi-omics tools, when coupled with artificial intelligence and synthetic biology, enable the precise design of targeted bioinoculants and synthetic microbial consortia. Translating these advanced microbiome-based strategies into scalable, field-level agricultural applications provides a sustainable path toward securing global food production while maintaining soil health. Global climate change imposes multifaceted abiotic and biotic stresses on crops, disrupting physiological and molecular processes and threatening agricultural productivity. Plant-associated microbes represent an underexplored yet powerful ally in enhancing crop resilience. This review presents current knowledge of plant-microbe interactions and the molecular mechanisms governing plant stress physiology, with an emphasis on climate-resilient and sustainable farming. Hence, ever-changing environmental cues pose a significant burden on agricultural productivity, and plant-associated microbial communities modulate a cascade of physiological and molecular responses, including production of phytohormones, signaling, regulation of reactive oxygen species homeostasis, and activation of plant immune responses to help plants withstand stress and enhance productivity. Moreover, root exudates, phytohormones, and quorum sensing mediate the central communication networks, facilitating plant-microbe cross talk. Additionally, the advances in OMICs approaches aid in disentangling the molecular underpinnings of these interactions by providing mechanistic insights and potential candidate gene targets for crop improvement and stress resilience. In the post-genomic era, integrating artificial intelligence and big data analysis to optimize microbiome-based strategies for sustainable agriculture is a new frontier for disentangling plant-microbe symbiosis to improve soil health, enhance crop yields, and improve stress tolerance. Thus, by integrating the ecological, physiological, and molecular perspectives, this review highlights the transformative potential of harnessing plant-microbe symbiosis for climate-resilient and sustainable agriculture.

Stress, Physiological

Proteoglycans nondissociatively extracted from different zones of canine normal articular cartilage: variations in the sedimentation profile of aggregates with degree of physiological stress.

Proteoglycans were extracted and purified without dissociation (a-A1 preparations) from superficial and deeper layers of high weight-bearing (HWA) and low weight-bearing (LWA) areas of dog normal articular cartilage. These proteoglycans were then characterized by velocity gradient centrifugation. In each of the 4 different topographical regions, the weight average sedimentation coefficients related strongly with total hexuronate content of the tissue. In the superficial layers, almost all aggregates had low sedimentation coefficients: the aggregates were smaller and less abundant in LWA than in HWA. The deeper layers contained an additional population of faster sedimenting aggregates which appeared smaller and less abundant in LWA than in HWA. Quantification and functional characterization of aggregates as well as in vitro aggregating studies showed that the topographical differences in size and content of aggregates were related to differences in content of hyaluronate and link protein in the a-A1 preparations. Superficial a-A1 specimens contained twice as much hyaluronate as deeper a-A1 preparations and their hyaluronate content increased with degree of physiological stress. Deeper a-A1 specimens from weight-bearing areas did not differ in their hyaluronate content but experiments assessing the saturation with link protein of these different a-A1 preparations suggested that specimens from HWA contained more active link than those from LWA. In contrast, the capacity of aggregation of a-A1D1D1 proteoglycan monomers as well as the molecular weight (Mr = 5 x 10(5) and aggregating capacity of hyluronate molecules appeared very similar in all a-A1 preparations from areas of articular cartilage. It is hypothesized that the synthesis of the three constituents necessary for aggregate formation (i.e. proteoglycan monomers as well as hyaluronate and link protein molecules) increases with degree of physiological load and that aggregation helps to maintain within cartilage the high concentration of proteoglycans that are essential for its biomechanical functions. The reported topographical variations in the distribution of proteoglycan aggregates reflect probably a maximal adaptation of the physiologic and biomechanical properties of the matrix to meet the high stress levels experienced by the articular cartilage in vivo.

Animals

Physiological stresses related to hypercapnia during patrols on submarines.

Physiological studies on hypercapnic effects carried out on 13 Polaris patrols are summarized. The average CO2 concentrations ranged from 0.7-1% CO2; CO2 was identified as the only environmental contaminant of the submarine atmosphere that has a direct effect on respiration in the concentration range found in the submarine atmosphere. A comparison has been made of physiological effects produced during 42 days of exposure to 1.5% CO2 during laboratory studies (L.S.) with those observed during 50 to 60 days of exposure to 0.7-1% CO2 on patrols (P.S.). A close similarity was found in the effects on respiration and blood electrolytes under both conditions. Respiratory minute volume was elevated by 50-63% because of increased tidal volume. The physiological dead space increased 60%. Vital capacity showed a trend toward a decrease. Studies of acid-base balance carried out during patrols demonstrated cyclic changes in blood pH and bicarbonate; pH and blood bicarbonate fell during the first 17 days of exposure, rose during the subsequent 20 days, and decreased again after 40 days. These cycles cannot be explained on the basis of known renal regulations in CO2-induced acidosis and were not found during exposure to 1.5% CO2. The hypothesis is advanced that these changes in acid-base balance are caused by cycles in CO2 uptake and release in bones. The time constants of the bond CO2 stores fit the observed length of cycles in acid-base balance. Correlation with cycles of calcium metabolism provides further support for this hypothesis. Red cell electrolytes showed similar changes under 1.5% CO2 (L.S.) and 0.7-1% CO2 (P.S.). Red cell sodium increased and potassium decreased. Moreover, red cell calcium also increased under both conditions. The significance of these red cell electrolyte changes in regard to changes in permeability and active transport remains to be clarified. An increased gastric acidity was found during patrol (exposure to 0.8-0.95% CO2). The changes observed during patrols disappeared during the recovery periods.

Acid-Base Equilibrium

[Detection of noise-induced physiological stress and hearing loss in guinea pigs by means of an electro-cochleographic method (author's transl)].

One of the most essential prerequisites to the suitability of test animals used for studying the damage effect of noise on audition is the threshold determination with reasonable expenditure. Mention is made of an electro-cochleographic method to determine the click threshold and click threshold shift [TTS(C) and PTS(C)], resp., after an uninjured guinea pig has been subjected to noise. The temporary threshold shift following a short-term sonic exposure and the permanent threshold shift following a permanent sonic exposure reveal a far heavier effect on the guinea pig ear than on the human ear. However, the trends in stress and affection are so much alike in guinea pig and man that the former's involvement in studying the effects of audition-affecting noise on the human ear seems to be primising.

Adaptation, Physiological

Subacute physiological stress induced by phosphamidon on carbohydrate metabolism in midgut gland of prawn, Penaeus indicus.

Midgut gland carbohydrate metabolism of penaeid prawn, Penaeus indicus was studied on acute and acclimation to sublethal concentration of phosphamidon. The midgut gland tissue of acclimated prawn showed inhibited glycolysis with an onset of gluconeogenesis. In general acclimation to sublethal concentration resulted in the elevation of the synthetic phase of midgut gland carbohydrate metabolism.

Adaptation, Physiological

The dynamics of beta-endorphin release by the hypothalamic nuclei and pituitary gland in sheep under physiological and stress condition.

The secretion of beta-endorphin (beta-End) by the infundibular nuclei--median eminence (IN-ME) and paraventricular nuclei (PVN) of the hypothalamus and the anterior lobe (AL) of the pituitary gland was determined in 18 anestrous ewes by RIA assay of this opioid in perfusates collected from these formations. Perfusion with Ringer-Locke solution was carried out on the animals under resting and stress-full conditions, using a pushpull cannula method. Electrical footshocks were used as stress stimuli. Two series of perfusion experiments were performed. In the first, the perfusions were carried out over two hours and perfusates were collected before and during stress for 1 h. In the second series of experiments the dynamics of the release of the opioid by the IN-ME and the pituitary gland were followed by collecting five or six perfusates in 20 min fractions before and during stress, respectively. The first series of experiments showed that the concentrations of beta-End in perfusates from the pituitary gland were much higher than those from the hypothalamic nuclei and that the concentrations of this opioid during stressing rose significantly only in perfusates from the IN-ME nuclei. In the second series of experiments the release of beta-End from the IN-ME and pituitary gland was altered by stress. The shift was very characteristic in that the concentrations of the opioid during stimulation initially significantly rose and then gradually declined. The concentration of the opioid in the peripheral blood also rose at the beginning of stimulation and declined as stimulation continued.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Brain TRF immunoreactivity during various physiological and stress conditions in the rat.

Methanol extracts of several rat tissues (hypothalamus, amygdala, the rest of the forebrain, brain stem and pancreas) were partially purified in SP-cation exchange chromatography and measured in TRF radioimmunoassay. It was found that hypothalamic and amygdaloid TRF contents were highest during the light period of the day, but brain stem TRF had an opposite rhythm. Hypothalamic TRF content rose after 10 min by 14% (p less than 0.05) when the rats were exposed to transfer stress. During short-time immobilization stress tests, hypothalamic TRF rose by 41% (p less than 0.05) after a 10-sec immobilization. Cold exposure did not produce any changes in hypothalamic TRF contents within 45 min. Handling stress and time of day appear to be the most important factors influencing the hypothalamic TRF content and have to be taken into account when measuring TRF.

Animals

The effect of diazepam on physiologically measured stress.

Responses to stress were reduced significantly in healthy volunteer subjects when diazepam was used as a sedative. Decreases in response to painful stimuli in a nontreated group averaged 17 percent; decreases in response to the stimuli in the group sedated with diazepam averaged 84 percent.

Adolescent

Transcriptomic insights into thermal stress reveal physiological trade-off between thermal stress adaptation and reproductive investment in Spodoptera litura.

Spodoptera litura, a highly polyphagous lepidopteran pest, poses a major threat to agricultural productivity due to its remarkable adaptability to diverse environmental conditions. Although heat stress is known to trigger transcriptional reprogramming in insects, the molecular mechanisms underlying thermal stress responses in S. litura remain poorly understood. In the present study, fourth-instar larvae were exposed to acute heat stress (44 °C) and compared with control conditions (27 ± 1 °C) to investigate heat-induced transcriptional alterations affecting physiology and reproduction. High-quality RNA-Seq data achieved more than 80% mapping efficiency, with a total of 15,782 transcripts were identified. Transcriptome analysis of S. litura larvae showed 323 differentially expressed genes (DEGs), of which 262 genes were significantly upregulated and 61 were downregulated in heat-stressed larvae compared to the control group. The DEGs were associated with stress response, reproduction, signalling, proteostasis, detoxification, oxidative stress, metabolism, development, and chromatin regulation. Heat shock proteins genes, including HSP70, HSP90, and HSP27, together with co-chaperones such as TRET-1, STIP1, and Starvin, were strongly upregulated, indicating enhanced cellular protection against protein damage and oxidative stress under heat stress. Conversely, key reproductive and cell cycle-related genes, including BARR, CAPD2, FEO, CDK2 and MORULA, were significantly downregulated, suggesting reproductive impairment and developmental arrest. RT-qPCR validation corroborated the RNA-Seq findings, demonstrating a heat-induced physiological trade-off that prioritizes survival over reproduction. Consistent with these molecular responses, heat-stressed insects exhibited marked reproductive impairment, including significant reductions in gonadosomatic index, eupyrene sperm bundle count, mating frequency, mating success, female calling behaviour, copulation duration, fecundity, and egg fertility. Collectively, these findings provide comprehensive insights into the molecular basis of thermal adaptation in S. litura and demonstrate that acute heat stress compromises reproductive fitness while activating conserved stress-response pathways that promote short-term survival.

Animals

Emergency nursing care of the burned patient.

The emergency nursing care of patients with major burns presents one of nursing's greatest challenges. Priority is given to lifesaving measures. After a quick overall assessment, a careful estimate of fluid and electrolyte loss is made. An issue in burn care is whether colloids should be given in the immediate postburn period. Large amounts of fluid are always given, and balanced salt solutions are being used increasingly without colloid. The patient's response to fluid therapy can be monitored by central venous pressure readings, vital signs, and hourly measurements of urinary output. Psychologic and physiologic stress intensify the problems and should be kept to a minimum. Only after other aspects of care have been attended is attention directed to care of the burn wound.

Burns

The hypothalamo-hypophysial system in Acipenseridae. V. Ecological-histophysiological analysis of the neurohypophysis of the female sturgeon Acipenser güldenstädti Brandt during up-stream migration and after spawning.

Neurohypophyses from sexually mature female sturgeons, Acipenser guldenstadti Brandt, killed before, soon after spawning, and during down-stream migration were studied light and electron microscopically. Ovaries were examined only under a light microscope. A large amount of neurosecretory material (3.5-4.5 arbitrary units) is found in the neurohypophysial "roots" during up-stream migration to spawning grounds. Neurosecretory fibres and their terminals are replete with elementary neurosecretory granules. Side by side with the latter some terminals contain single residual granules and few "synaptic" vesicles. Soon after spawning the amount of neurosecretory material decreases markedly in most individuals (content up to 1-3 units), and elementary granules are few in the fibres and their terminals. The number of residual granules increases, and "synaptic" vesicles are especially numerous. Granulated, disintegrating neurosecretory granules and granule-shadows occur in the preterminal parts of the fibres. The number of pituicytes increases becuase some "light" tanycytes seem to migrate from the ependymal into the subependymal layer. The restoration of neurosecretory material (reaching again up to 3.5-4.5 units) occurs within a month after spawning. The number of elementary granules increases in fibres and terminals while that of residual granules and "synaptic" vesicles decreases. These changes in the neurohypophysis of females after spawning are due to discharge of great amounts of peptide neurohorsmones into the general circulation after spawning. Spawning is regarded as a "physiological" stress for these females.

Animals

Physiological costs of combating chemical toxicants: ecological implications.

1. Evidence is presented that combating the poisoning effects of toxic chemicals is metabolically costly. 2. This has implications for relating physiological stress responses observed at the level of individual organisms to population effects, and needs to be incorporated explicitly into models making this link. 3. The cost hypothesis also has implication for the evolution of stress resistance either as a fixed or facultative (inducible) response. Optimization models incorporating these ideas are reviewed and discussed.

Animals