Minute Period Research Articles

Validation of scan sampling techniques for nursery pig feeder- and nutritional enrichment use

The objective of this study was to validate scan sample accuracy at various predetermined intervals relative to continuous observation of individual nursery pigs interacting with a feeder and nutritional enrichment. A total of 280 mixed-sex pigs, 19 to 24 days of age were randomly allocated to 28 pens. Pen was the experimental unit, and 7 pens were assigned to each of 4 treatments: (1) biscuit with maternal pheromone attractant (MP), (2) biscuit with sugary attractant (strawberry jam) (JAM),(3) biscuit with no attractant (positive control; POS), and (4) no biscuit (negative control; NEG). Each enrichment pen received 4 biscuits suspended from 2ropes at the feeder for the first 7 days after weaning. The biscuit enrichments were added to the nursery pen at ~ the 15:00 hour on Day 0 and ~ the 08:30 hour on Days 1-6. Behavior observations were performed using continuous sampling of all nursery pigs in each pen during the first 30 minutes after biscuit placement on Days 0 to 6 (98 total hours, 3.5 hours/pen). The number of time each pig interacted with the feeder and biscuit was recorded as well as the duration of each interaction. These continuous observations were then used to create different data sets at varying sample times. The scan sample and continuous data were analyzed using the GLM procedure of SAS and behavioral frequency data were expressed as percentage of time (s) pigs were performing an identified behavior during the 30-minute observation periods. For enrichment use, there was no observed statistical difference between data collected using continuous observation, 10 second scans and 15 second scans when comparing continuous to 5 second scans, 10 second scans, 15 second scans and 30 second scans. For feeder use, there was no observed statistical difference between data collected using continuous observation and the 30 second scan sample when comparing continuous to 15 second scans, 30 second scans, 45 second scans and60 second scans. In conclusion, 30 second scan sampling for feeder use and 10second and 15 second scan sampling for enrichment use can be used, without being different to the continuous or “gold  standard” methodology. These scan point validations are critical because they allow the observer to collect more total data in less time without giving up accuracy.

Blood Lactate and Heart Rate Responses Between Active and Passive Recovery Modes Over a 15-Minute Recovery Period in Female Dancers After Kathak Dance.

Introduction: Dance is physically demanding and results in blood lactate (BL) accumulation and elevated Heart Rate (HR). Researchers recommend using either Active Recovery (AR; eg, low-to-moderate intensity-exercise) or Passive Recovery (PR; eg, complete rest) modes after activity. We compared BL and HR responses between AR or PR over a 15-minute recovery period following a Kathak dance. Methods: Twelve female dancers (31.0 ± 6.0 years; 161.5 ± 4.9 cm; 55.5 ± 5.8 kg) performed 2 dance testing sessions (Day 1 = AR, Day 2 = PR) 48 hours apart. Each session started with a 10-minute warm up followed by dancers performing four 2-minute stages of Kathak dance, with three 1-minute periods between stages where we recorded HR and their Rate of Perceived Exertion (RPE:scale = 6-20) to match the intensity of both sessions. Post-dance, we recorded dancers' BL and HR at 1, 3, 5, 10, and 15 minutes while they recovered via AR or PR. Separate 2(mode) × (time) Repeated-Measures-ANOVA followed by simple-main-effects testing and adjusted Bonferroni-pairwise-comparisons examined differences in BL and HR responses across modes and time(α = .05). Results: Dancers' HR and RPE were similar across sessions. No mode × time interaction existed in BL (F4,8 = 3.6, P = .06). BL levels were similar across modes (F1,2 = 0.5, P = .5). BL levels reduced over time (F4,8 = 6.0, P = .02), but Bonferroni-comparisons did not reveal any pairwise differences. In HR a significant mode*time interaction (F4,36 = 11.0, P = .01, η2 = .55) was observed. Both Active and Passive recovery modes achieved absolute HR levels by 15 minutes, with PR mode stabilizing within 5 minutes. Conclusions: Over a 15-minute recovery period after Kathak dance, dancers' BL and HR responses were similar across time in both AR and PR, with HR being higher in AR. Dancers' HR remained similar from 1 to 3 minute post dance recovery and then dropped over time. Thus, dancers can rest up to 3 minutes and still maintain the same elevated HR. Overall, dancers can choose either AR or PR as their recovery mode based on their individual preferences.

Role of Plant Growth Regulators on Multiplication of Stevia rebaudiana Inside Manufactured Temporary Immersion Bioreactor and Induction of Callus from Explant

The experiment was conducted at Plant Tissue Culture Laboratory - Department of Horticulture and landscape gardening, from October 2021 to January 2023. micropropagation experiments were conducted using five levels of Kinetin 0.0, 1.0, 2.0, 3.0, and 4.0 mg L. Callogenesis experiments were performed using four levels of Naphthalenacetic Acid 0.0, 1.0, 2.0, and 3.0 mg L. A temporary immersion bioreactor was used with a 10-minute immersion period every 4 hours, and two levels of Kinetin and two levels of benzyl adenine were added to the Murashige and Skoog medium as a comparative treatment. The results showed that the concentration of 1.0 mg L had a significant effect on the number of shoot and leaves, and the comparative treatment showed a significant effect on shoots height. The results of multiplication in the manufactured bioreactor showed a significant effect on shoots height, reaching 4.8 cm, and the concentration of 1.0 mg L benzyl adenine showed a significant effect on the number of shoots, with 3.2 shoot per plant, and the number of leaves for the same treatment was 17.1 leaves per shoot.

Contributed Session III: Active vision shapes ocular dominance.

Ocular dominance is a basic visual property that shows short-term plasticity in adult humans, where 2h of monocular deprivation leads to a homeostatic shift of ocular dominance in favour of the deprived eye. Using an altered reality setting, we found that this homeostatic plasticity can be triggered without depriving one eye of visual input, but merely perturbing the temporal correspondence between voluntary actions and vision in one eye. Participants wore a VR set; its monocular screens were connected with cameras monitoring the front space, which participants used to perform a complex visuomotor task. During a 60 minute period, the input to the dominant eye was delayed by 333 ms, making it useless for visuomotor coordination. Following this, ocular dominance (quantified by binocular rivalry) was systematically shifted in favour of the delayed eye, a similar effect as that produced by monocular contrast-deprivation. The shift was only observed when participants actively engaged in the visuomotor task, not when they passively watched a confederate perform the same task. We interpret these results in the light of parallel fMRI experiments where monocular deprivation is associated with a global system reconfiguration that pivots around a key area for sensorimotor integration, the Pulvinar. Based on our findings, we suggest that active vision is foundational to weighting sensory information, even at the level of simple visual processes as those setting ocular dominance.

Analytical Method Development, Validation, and Applications of the HPTLC Densitometric Approach for Simultaneous Quantification of Azelnidipine and Chlorthalidone

For the simultaneous quantification of Azelnidipine and Chlorthalidone in synthetic combination, a high performance thin layer chromatographic method was devised that is quick, accurate, selective, and exact. The mobile phase used in the chromatographic analysis was in the ratio of 5: 4.7: 0.3: 0.1 v/v/v/v, and the stationary phase utilised was silica gel 60 F254 as the precoated stationary phase on aluminium plates. A 10 x 20 cm TLC chamber with a 15-minute saturation period was utilised. Azelnidipine and chlorthalidone were found to have retardation factors (RF) of 0.43 0.03 and 0.30 0.02, respectively. At 242 nm, densitometric analysis was performed. Following the ICH Q2 (R1) standard, a validation study was conducted. The calibration plots' regression data revealed a strong linear association with R2 = 0.999 for the concentration ranges of azelnidipine and chlorthalidone, 400–1200 ng band-1 and 600–1800 ng band-1, respectively. The method's precision, accuracy, and robustness were all validated. For azelnidipine and chlorthalidone, the minimum detectable levels were determined to be 26.71 ng band-1 and 38.39 ng band-1, respectively, and the limits of quantitation were found to be 80.94 ng band-1 and 116.033 ng band-1. Azelnidipine and chlorthalidone can be estimated simultaneously for routine analysis, in drug formulations, and in biological matrices, in short, using the proven analytical approach.

Insights into electro-bioremediation of PAH-contaminated soil under polarity reversal conditions: Effect of effective current intensity and soil properties on microbial function

Electrical stimulation during electro-bioremediation has the potential to enhance the biodegradation of polycyclic aromatic hydrocarbons (PAHs) in soil. In this study, we investigated the effective current intensity, referred to as the “window condition,” which promotes the activity of functional microflora. Electro-bioremediation was performed on PAH-contaminated soil using various polarity reversal frequencies (PRF) to study the remediation mechanism. The “window condition” in this study was 20–40 mA. The enhancement of PAH degradation, particularly that of high-PAHs, increased with higher PRF, which accompanied the increasing ratio of the “window condition” to the overall electrification time (RWC). Electro-bioremediation with a 10-minute (EBPR-10 m) and 30-minute (EBPR-30 m) polarity reversal (PR) periods achieved the highest ratios of PAH degradation at 43.9±2.3 % and 37.9±1.8 %, respectively, with RWC of 0.4919 and 0.4056, respectively, after 60 days. The increase in PRF improved the soil physicochemical properties, which were conducive to maintaining effective electrokinetic and biodegradation processes. Redundancy analysis (RDA) and Pearson correlation analyses demonstrated that soil electrical conductivity (EC), dissolved organic carbon (DOC), temperature, and the proportion of macroparticle components (0.195–2.500 um) in soil colloids (Ps/Po) were key factors in explaining the persistence of microbial abundance and community structure. Structural equation models (SEMs) further illustrated the mechanism behind the enhanced PAH biodegradation, including (i) the direct stimulation of microbial activity because of increased RWC and (ii) the indirect optimization of microbial function by improving soil physicochemical properties under optimal PRF.

Genetic and Physiological Predictors of Bioenergetic Adaptation Skeletal Muscles in Athletes of Cyclic Sports

When performing maximum loads, an important criterion for assessing prospects is the achievement of the best result with the least metabolic changes in the body of athletes, which indicates the possibility of further increasing physical performance. The study of the mechanisms of energy supply and the reaction of body systems when testing performance under special conditions is one of the important conditions for the development of additional biochemical criteria for assessing the prospects of athletes. Purpose: To study genetic and physiological predictors of bioenergetic adaptation of skeletal muscles in athletes of cyclic sports. Methods: 76 athletes of cyclic sports (speed skating, running disciplines in track-and-field) of European origin who lived in the Southern Urals region took part in the study. The average age of the study participants was 22.1 ± 2.5 y.o. Experience in sports was at least 5 years. We used the Step One Real-Time PCR System (Applied Biosystems, USA) device for real-time polymerase chain reaction. The study of bio-energetic indicators of athletes' physical performance was carried out using the bicycle ergometry method (test with maximum load). Biochemical studies were carried out using a Lactate Scout Plus lactometer. Results: Significant differences were found in the ΔLa (%) indicator: in athletes with a dominant homozygous genotype R/R, lactate clearance during a 10-minute rest after performing a bicycle ergometer load is statistically significantly higher than in athletes with a recessive homozygous genotype X/X (20.14±12.74%, versus 11.11±3.12%; p<0.05). The major allele C (R) was associated with moderate and high lactate clearance (OR = 2.25 [95% CI: 0.99 – 5.11] and OR = 2.24 [95% CI: 0.91 – 5.51], respectively). At the same time, a statistically significant association was identified between the minor allele T(X) and the homozygous genotype TT (XX) with low lactate clearance (OR = 12.14 [95% CI: 1.30 – 13.55]). High values of lactate clearance indicate the utilization of lactate from peripheral blood and more efficient recovery processes in carriers of the major allele C (R). Conclusions: lactate clearance during a 10-minute rest period after a bicycle ergometer test with maximum load and DNA profiling of the ACTN3 gene rs1815739 can be recommended as significant physiological and genetic predictors of bioenergetic adaptation of skeletal muscles in cyclical sports athletes of Caucasian origin in the Southern Urals.

Near-Infrared Spectroscopy Monitoring to Detect Changes in Cerebral and Renal Perfusion During Hypovolemic Shock, Volume Resuscitation, and Vasoconstriction.

Rapidly changing hemodynamic conditions, such as uncontrolled hemorrhage and the resulting hypovolemic shock, are a common contributor to active duty military deaths. These conditions can cause cerebral desaturation, and outcomes may improve when regional cerebral oxygen saturation (CrSO2) is monitored using near-infrared spectroscopy (NIRS) and desaturation episodes are recognized and reversed. The purpose of this porcine study was to investigate the ability of NIRS monitoring to detect changes in regional cerebral and regional renal perfusion during hypovolemia, resuscitation by volume infusion, and vasoconstriction. Hemorrhagic shock was induced by removing blood through a central venous catheter until mean arterial pressure (MAP) was <40 mmHg. Each blood removal step was followed by a 10-minute stabilization period, during which cardiac output, blood pressure, central venous pressure, blood oxygen saturation, and CrSO2 and regional renal oxygen saturation (RrSO2) were measured. Shock was reversed using blood infusion and vasoconstriction separately until MAP returned to normal. Statistical comparisons between groups were performed using the paired t-test or the Wilcoxon signed-rank test. Using volume resuscitation, both CrSO2 and RrSO2 returned to normal levels after hypovolemia. Blood pressure management with phenylephrine returned CrSO2 levels to normal, but RrSO2 levels remained significantly lower compared to the pre-hemorrhage values (P < .0001). Comparison of the percent CrSO2 as a function of MAP showed that CrSO2 levels approach baseline when a normal MAP is reached during volume resuscitation. In contrast, a significantly higher MAP was required to return to baseline CrSO2 during blood pressure management with phenylephrine (P < .0001). Evaluation of carotid blood flow and CrSO2 indicated that during induction of hypovolemia, the two measures are strongly correlated. In contrast, there was limited correlation between carotid blood flow and CrSO2 during blood infusion. This study demonstrated that it is possible to restore CrSO2 by manipulating MAP with vasoconstriction, even in profound hypotension. However, MAP manipulation may result in unintended consequences for other organs, such as the kidney, if the tissue is not reoxygenated sufficiently. The clinical implications of these results and how best to respond to hypovolemia in the pre-hospital and hospital settings should be elucidated by additional studies.

The acute psychological effects of screen time and the restorative potential of nature immersion amongst adolescents: A randomised pre-post pilot study

Excessive screen time can deplete the cognitive resources required for effective emotion regulation, such as sustained attention and inhibitory control. Contrastingly, time spent in natural environments encourages attention restoration and stress reduction. Therefore, time in natural environments may be important for buffering the psychological consequences of screen time. A randomised pre-post pilot study was undertaken to investigate the acute psychological effects of screen time in adolescents, and to explore the restorative potential of nature immersion. Eighty-seven adolescents (52% female, mean age = 15.5 years) participated in the study. Participants completed measures of mood, sustained attention capacity (Sustained Attention to Response Task), and inhibitory control (Stop-Signal Task) at three time-points: (1) at baseline, (2) after a 30-minute period of screen time, and (3) after a 20-minute period of rest. Participants were randomised to either an indoor setting or an outdoor environment (Botanic Gardens) for the rest period. Linear mixed modelling was used to examine the effect of time and resting condition on the outcome variables. A lack of change in baseline mood, sustained attention capacity, and inhibitory control was observed following the brief screen time period, which limited the ability to test the relative benefit of the outdoor vs indoor environment. The study demonstrated the feasibility of a novel and ecologically valid paradigm to test this relationship in school students, but future studies should look to apply the recommendations provided regarding altering the attentional demands of the screen time activity used. The potential for natural environments to benefit student wellbeing and performance remains an important area of continued research.

Effect of a single intravenous injection of branched chain amino acids on body temperature of cats undergoing general anesthesia

ObjectiveTo evaluate the effect of a single intravenous injection of branched chain amino acids (BCAAs) on body temperature in cats undergoing general anesthesia. Study designProspective, blinded, randomized, crossover, experimental study. AnimalsA total of 10 healthy adult cats (five female and five male). MethodsCats were anesthetized three times with three different treatments in a random order: 3 mL kg–1 lactated Ringer’s solution (LRS), 100 mg kg–1 BCAAs (B100) or 200 mg kg–1 BCAAs (B200) solution immediately before induction of anesthesia. After induction, rectal temperature was measured every 5 minutes. Blood samples were collected for the measurement of blood glucose (BG) just before induction, at the end of the 90 minute period of anesthesia, and 24 hours after anesthesia induction. The differences between baseline and each subsequent rectal temperature, and BG measurements were analyzed. Areas under the curve (AUCs) for temperature differences were calculated for each animal for the anesthetic period (AUCT0–90). Parametric or nonparametric data were analyzed by one-way repeated measures anova or Friedman test. A value of p < 0.05 was considered significant. ResultsThere were no significant differences in AUCT0–90 between groups: 41.6 ± 7.7 for LRS, 43.4 ± 6.9 for B100 and 42.9 ± 7.5 for B200 (p = 0.368). No significant differences were observed in BG between groups at 90 minutes and 24 hours after anesthesia induction (p = 0.283 and p = 0.089, respectively). The incidence of hypoglycemia [BG ≤ 3.17 mmol L–1 (57 mg dL–1)] after anesthesia tended to be higher in both B100 (4/10 cats) and B200 groups (3/10 cats) than in LRS group (1/10 cats). Conclusions and clinical relevanceA single, preanesthetic intravenous injection of BCAAs did not attenuate heat loss during anesthesia. More cats were hypoglycemic in the BCAA groups than in the LRS group.

Abstract 315: Endovascular Aortic Occlusion Preferentially Improves Hemodynamics and Return of Spontaneous Circulation After Longer Periods of Cardiopulmonary Resuscitation: A Translational Study in Swine

Introduction: Non-traumatic cardiac arrest (NTCA) is associated with low survival and substantial societal cost. Standard-of-care treatments, such as cardiopulmonary resuscitation (CPR) and advanced cardiac life support (ACLS), have limitations in restoring cardiac function and improving outcomes. Resuscitative endovascular balloon occlusion of the aorta (REBOA) has emerged as an adjunct to CPR for NTCA. However, the optimal patient population that will benefit most from REBOA remains uncertain. Goals: This translational study investigated the impact of varying low-flow duration (15- vs 30-mins) on REBOA's hemodynamic performance and ability to achieve return of spontaneous circulation (ROSC) in a swine model of NTCA. Methods: Thirty-two swine were anesthetized and placed into ventricular fibrillation. All animals received a 4-min “no-flow” period before mechanical CPR was initiated. Animals were randomized into four groups to receive: 1) 15- vs 30-minutes of CPR; 2) REBOA vs. no-REBOA (control). After completion of the 15- or 30-minute low-flow period, ACLS was initiated and REBOA was fully-inflated in experimental animals. Results: There were no differences in demographics or hemodynamics at baseline (T = -10-mins) or at randomization (T = +10-mins). In the 15-mins groups, there were no differences in the rates of ROSC between REBOA (4 / 8, 50%) and control (4 / 8, 50%; p = 0.99). However, in the 30-min group the REBOA animals had a significantly higher rate of ROSC (6 / 8, 75%) compared to control (1 / 8, 12.5%; p = 0.04). In the 7-mins (T = 34 - 41 mins) after REBOA deployment in the 30-min animals there was a statistically significant difference in diastolic blood pressure (repeated measures ANOVA; p = 0.027). Importantly, 5 / 6 (83%) animals that received ROSC in the 30-min group with REBOA re-arrested at least once with 3 / 6 (50%) maintaining ROSC until study completion. Conclusion: In our swine model of NTCA, REBOA preferentially improved hemodynamics and ROSC after a 30-mins period of low-flow CPR, compared to 15-mins of low-flow CPR. REBOA may be a viable strategy to improve ROSC after prolonged downtime. More hemodynamic support will be required to maintain ROSC. This has implications for patient selection in upcoming human trials of REBOA in NTCA.

424 Botanical Composition and Quality of Beef Cattle Diets on a Burned Versus Unburned Foothills Rangeland

Abstract Current management paradigms suggest deferring grazing rangeland for two years after a wildfire to avoid additional stress on native plant species, but there is limited research supporting these recommendations. Therefore, this experiment was conducted within and adjacent to a burn area of an August 2020 wildfire to evaluate the differences in diet quality, botanical composition, and foraging efficiency of beef cattle grazing both burned and unburned rangelands. A randomized complete block design with a 2×2 factorial arrangement of treatments contrasting burn versus unburned and June versus September grazing periods were used. Pastures (4 ha) within the burn area were grazed in either June 2021 or deferred to September 2021. Grazing occurred for two days with 20 cow/calf pairs in June and 16 cow/calf pairs in September. Cattle diet composition and masticate samples were collected during 20-minute bite-count periods using six ruminally cannulated cows in each pasture prior to and after the two-day grazing periods. Cannulated cows grazed a pasture adjacent to the burn area to compare diet quality and composition between burned and unburned rangeland. Diet composition displayed a burn treatment by season of use interaction (P &amp;lt; 0.01) with greater forb consumption in burned than unburned in June (P &amp;lt; 0.01), but not different in September (P = 0.58). Additionally, both bites per minute and grams per minute displayed a treatment by season of use interaction (P &amp;lt; 0.01). Specifically, cattle grazing unburned pastures in June tended to take more bites per minute (P = 0.07) than in burned pastures. In contrast, the opposite was observed with September diets where cattle took more bites per minute in burned pastures than unburned pastures (P &amp;lt; 0.01). Grams per minute did not differ between September treatments (P = 0.26), but cattle did consume more grams per minute in unburned pastures in June (P &amp;lt; 0.01). The ash content of diets tended to display a treatment by season of use interaction (P = 0.09) with dietary ash tending to be greater in burned pastures in June (P = 0.07), but not differing in September (P = 0.54). Both dietary NDF and CP displayed a treatment by season interaction (P &amp;lt; 0.01), where crude protein was greater and NDF was lower for June burned pastures than unburned pastures (P &amp;lt; 0.01) but did not differ in September (P ≥ 0.27). In summary, diet quality was improved for grazing during the growing season after wildfire. The differences in diet quality may be related to the increase in forb consumption in post-fire vegetation communities.

The Effects of Apohemoglobin-Haptoglobin on Heme-Induced Coagulation

Introduction: In conditions with significant hemolysis, like sickle cell and thalassemia, red blood cells break down, leading to higher levels of cell-free hemoglobin (Hb) in the bloodstream. When this cell-free Hb is oxidized into methemoglobin, it releases heme, a crucial iron-protoporphyrin complex essential for oxygen transport. However, excessive free heme can become problematic, since plasma concentrations of the body protective proteins, haptoglobin and hemopexin, to scavenge and clear hemoglobin and heme is very limited. Thus, these protective mechanisms can get overwhelmed by high levels of free Hb or heme in the blood. Additionally, heme can interact with the coagulation cascade, potentially causing harmful pro-coagulant effects in the body. To address this, we introduce a new synthetic scavenger protein called apohemoglobin-haptoglobin (apoHb+Hp). It mimics hemopexin's function and binds to free heme with even greater affinity. Moreover, it utilizes haptoglobin's clearance mechanism for efficient removal from the plasma. Our aim is for apoHb+Hp to effectively clear free heme from the plasma, thereby alleviating pro-coagulatory markers induced by heme. This novel approach may enhance the body's natural defense against heme, leading to potential therapeutic benefits. Materials and Methods: This study used male Sprague-Dawley rats to investigate the effect of apoHb+Hp on coagulation markers during conditions of excess heme. To do so, 20% of the blood volume, estimated as 7% of body mass, was removed from the animal over a 10 minute period. After 10 minutes of rest, the removed blood volume was re-infused to the animal as either 20% lactated ringers, 20% apoHb+Hp, 10% heme bound to human serum albumin (HSA) and 10% apoHb+Hp, or 20% heme HSA. After a 30-minute rest period, 70 µm and 5 mL blood samples were drawn from the tail vein and arterial catheter, respectively, to evaluate measures of the coagulation cascade including prothrombin time, active partial thromboplastin time, fibrinogen, soluble glycoprotein V, Thrombin/ antithrombin complex (TAT), thromboelastography (TEG). Results: Re-injection of Heme HSA resulted in activation of the coagulation system as evidenced by an increase in TAT and soluble glycoprotein V. This effect was reversed with co administration of ApoHb-Hp. Heme HSA caused activation of the extrinsic pathway, as measured by TEG (EXTEM) and a reduction in PT, this effect was ameliorated upon treatment with apoHb-Hp. No notable changes were seen in the intrinsic pathway factors as evidenced by the PTT or TEG/ INTEM. Discussion: Previous literature has established that heme has significant effects in the extrinsic and common pathways of the coagulation cascade, and our study is consistent with these results. When combined with heme HSA, however, apoHb+Hp was able to improve some of the thrombotic effects induced by the addition of heme HSA to circulation. Conclusions: Excess free heme can contribute to a hypercoagulable state. As expected, our findings showed significantly notable pro-coagulatory state in the presence of excessive heme in the blood. ApoHb+Hp attenuates heme-induced prothrombotic states to some extent in the extrinsic and common pathways. ApoHb-Hp may be a potential therapeutic strategy in hemolytic anemias and further studies to evaluate its role in pathologic states associated with hemolysis is warranted.

The use of bio-oil from biodiesel production for enhancing the bitumen healing

Road pavements are exposed to traffic and temperature effects that produce distress, mainly cracking that leads to pavement failure, after which rehabilitation actions are necessary to extend pavement life. Bio-rejuvenators have been used to recover the bitumen properties lost due to fatigue of the asphalt mixtures and ageing due to temperature variations and oxidation. Thus, this paper investigates the healing of bitumen modified with bio-oil derived from biodiesel production. One base bitumen in three different ageing stages (unaged, short and long-term ageing) was used for adding up to 3% of bio-oil to the bitumen. In addition to consistency and rheological tests to characterise the modified bitumen, fatigue resistance tests with and without rest periods were performed to assess the healing through three indexes, relating the complex shear modulus, the number of cycles to failure and the amount of damage, after a rest period. It was verified that the healing follows an exponential law with the rest period, but the number of cycles in each loading period decreases compared to the previous period. For a 15-minute rest period, the healing was limited to 26.9%, but the bio-oil contributed significantly to that restoration.

Emotion regulation tendencies and cardiovascular responses to repeated acute psychological stress

Poor emotion regulation has been associated with cardiovascular disease (CVD) through maladaptive cardiovascular responses to psychological stress. However, there has been scant research examining the relationship between emotion regulation and habituation of cardiovascular responses to recurrent stress, which may be more directly applicable to the experience of stress in everyday life. The aims of the current study were to examine the associations between emotion regulation tendencies and cardiovascular stress reactivity, as well as habituation of cardiovascular reactivity across repeated stressors. A sample of 453 participants (mean (SD) age = 19.5 (1.3) years; 62 % women) completed a repeated stress paradigm, which consisted of two 10-minute baselines and two identical 4-minute stress tasks, separated by a 10-minute recovery period. Heart rate (HR) was measured continuously; systolic/diastolic blood pressures (SBP/DBP) were measured every 2 min. At the end of the visit, participants completed the Emotion Regulation Questionnaire (ERQ) and Difficulties in Emotion Regulation Scale (DERS). Results indicate that impulse control difficulties when distressed (a DERS subscale) were significantly associated with blunted SBP, DBP, and HR reactivity to both stressors, as well as impaired HR habituation across the stressors. None of the ERQ subscales (cognitive reappraisal, expressive suppression) were found to be associated with cardiovascular stress reactivity or habituation. The outcomes of this study demonstrate a potential underlying physiological pathway through which impulse control difficulties when distressed may contribute to CVD risk. This study also reveals the importance of extending traditional cardiovascular stress reactivity protocols to include multiple exposures of the same stress task.

On the Causes and Environmental Impact of Airborne Holdings at Major European Airports

This paper introduces a data-driven technique for labelling airborne holdings based on their underlying causes, specifically distinguishing between adverse weather conditions and other causes, such as airport capacity. Utilising a dataset comprised of flight trajectories arriving at 45 European airports over a nine-month period, extracted from automatic dependent surveillance-broadcast data, this paper provides valuable insights into the causes behind airborne holdings and their relative environmental impact. The proposed approach involves employing an existing neural network to identify airborne holdings. Subsequently, these holdings are cross-referenced with actual weather observations obtained from meteorological aerodrome reports. Following this, a subset of the holdings is labelled as either weather-related or attributed to other causes, based on historical air traffic flow management regulations. Finally, the cause of the majority of unlabelled holdings is determined using semi-supervised learning. The findings indicate that at least one-quarter of the 30-minute time periods with airborne holdings identified by the neural network can be attributed to weather-related factors, with reduced visibility, strong winds, and convective weather, emerging as the primary contributing events. Intriguingly, weather-related causes account for approximately 40% of the total fuel consumption associated with these procedures.

Effects of phenylbutazone, firocoxib, and dipyrone on the diuretic response to furosemide in horses.

Treatment with phenylbutazone (nonselective COX inhibitor) decreases the diuretic and natriuretic effects of furosemide by nearly 30% but the effects of COX-2 specific inhibitors (firocoxib) and atypical NSAIDs (dipyrone) are unknown. Furosemide-induced diuresis after pretreatment with firocoxib or dipyrone is diminished to a lesser extent than after pretreatment with phenylbutazone. Eight healthy mares. Each mare received 4 treatments in a prospective experimental crossover study using a replicated 4 × 4 Latin Square design: furosemide alone (FU), furosemide and phenylbutazone (PB), furosemide and firocoxib (FX), and furosemide and dipyrone (DP). After 24 hours of NSAID treatment at recommended dosages, ureteral catheters were placed for continual urine collection. After a 30-minute baseline collection period, furosemide (1.0 mg/kg, IV) was administered, and urine and blood samples were collected for 4 hours. Data were assessed by repeated measures ANOVA. Four-hour urine volume was (mean ± SD) ~25% less (P < .001) after pretreatment with all NSAIDs (PB 19.1 ± 2.1 mL/kg, FX 17.7 ± 3.5 mL/kg, DP 19.1 ± 3.9 mL/kg), as compared to FU (23.4 ± 5.1 mL/kg) (P < .001), but there were no differences between PB, FX, or DP. Interindividual variability in furosemide diuresis after pretreatment with different NSAIDs was observed. Though COX-2 selective NSAIDs and dipyrone might have less severe or fever gastrointestinal adverse effects in horses, our data suggest minimal differences in effects on furosemide-induced diuresis, and possibly, risk of nephrotoxicosis.

An experimental study on lung deposition of inhaled 2 μm particles in relation to lung characteristics and deposition models

BackgroundThe understanding of inhaled particle respiratory tract deposition is a key link to understand the health effects of particles or the efficiency for medical drug delivery via the lung. However, there are few experimental data on particle respiratory tract deposition, and the existing data deviates considerably when comparing results for particles > 1 μm.MethodsWe designed an experimental set-up to measure deposition in the respiratory tract for particles > 1 μm, more specifically 2.3 μm, with careful consideration to minimise foreseen errors. We measured the deposition in seventeen healthy adults (21–68 years). The measurements were performed at tidal breathing, during three consecutive 5-minute periods while logging breathing patterns. Pulmonary function tests were performed, including the new airspace dimension assessment (AiDA) method measuring distal lung airspace radius (rAiDA). The lung characteristics and breathing variables were used in statistical models to investigate to what extent they can explain individual variations in measured deposited particle fraction. The measured particle deposition was compared to values predicted with whole lung models. Model calculations were made for each subject using measured variables as input (e.g., breathing pattern and functional residual capacity).ResultsThe measured fractional deposition for 2.3 μm particles was 0.60 ± 0.14, which is significantly higher than predicted by any of the models tested, ranging from 0.37 ± 0.08 to 0.53 ± 0.09. The multiple-path particle dosimetry (MPPD) model most closely predicted the measured deposition when using the new PNNL lung model. The individual variability in measured particle deposition was best explained by breathing pattern and distal airspace radius (rAiDA) at half inflation from AiDA. All models underestimated inter-subject variability even though the individual breathing pattern and functional residual capacity for each participant was used in the model.ConclusionsWhole lung models need to be tuned and improved to predict the respiratory tract particle deposition of micron-sized particles, and to capture individual variations – a variation that is known to be higher for aged and diseased lungs. Further, the results support the hypothesis that the AiDA method measures dimensions in the peripheral lung and that rAiDA, as measured by the AiDA, can be used to better understand the individual variation in the dose to healthy and diseased lungs.

P050 Process O (onset/offset) cause of the 90-min sleep cycle

Abstract The ubiquitous sleep cycles across a normal sleep of approximately 90 minute period length were originally suggested to be a reflection of a 90-minute basic rest-activity cycle (BRAC) operating across the full circadian cycle of wakefulness and sleep. The evidence for a BRAC during the wakeful period is sparce requiring other explanations for the prominent 90min cycles during sleep. Recently another process, Process O (onset/offset), has been suggested in addition to Processes S (homeostatic) and C (circadian). It was hypothesised in order to account for the recuperative effects of a brief power nap, inexplicable by the other two processes. Process O hypothesises a development of inhibition to any ongoing state (wake, NREM, REM). The inhibition develops rapidly over 1-2 hours to a plateaued limited level and then, following the cessation of that state, dissipates rapidly (5-15 minutes). Thus, a “power” nap brings improved alertness because of the short break from wakefulness allowing the dissipation of wakefulness Process O inhibition. It is suggested that Process O inhibition accumulates also to periods of NREM sleep and REM sleep. The ‘sleep switch’ accounting for bi-stable states of sleep or awake is hypothesised to include REM and NREM as separate states accounting for stability and mutual inhibition between 3 rather than just 2 states. Thus Process O inhibition developing to an ongoing state tips the balance to other states (REM or NREM) resulting in the alternation between them of the sleep cycles and allowing longer sleep epochs after brief awakenings.

Single-longitudinal-mode narrow linewidth broadband tunable Brillouin random laser including dispersion compensation fibers

We propose and demonstrate a single-longitudinal mode (SLM) narrow linewidth broadband tunable Brillouin random laser, including two segment dispersion compensated fibers (DCFs), in which enough narrowband Brillouin gain provided by a 2-km-length DCF to overcome the cavity loss, and Rayleigh backscattering (RBS) provided by a 1-km-length DCF form a mirrorless open cavity to continuously compress the laser linewidth. Compared to ordinary single mode fibers, DCF has an enhanced stimulated Brillouin scattering gain coefficient and RBS coefficient, which is attributed to its small core diameter structure, making the laser more compact and stable. Stronger random feedback effectively lowers the laser threshold, and enough Brillouin gain for multiple amplifications in random mode makes SLM operations more accessible. The proposed laser is with a threshold of ∼11 mW and an optical signal-to-noise ratio (OSNR) of ∼55.75 dB, the 3-dB linewidth and linewidth compression ratio of the output laser reaches ∼550 Hz and ∼236, respectively. By changing the wavelength of the pump laser, the laser wavelength can be continuously tuned in a broad wavelength range, which is only limited by tunable range of Brillouin pump laser. The laser wavelength fluctuation of 0.02 nm and the OSNR fluctuation of about 3 dB in a 30-minute measure period, indicating that the laser is with a good stability.