First Day Of Testing Research Articles

Use of anti-motion sickness reading glasses in vehicles: study protocol for a cluster-randomised trial

Motion sickness, or kinetosis, is a common phenomenon and is usually induced during passive locomotion in vehicles, generated by different body accelerations when movement stimuli occur. Its main symptoms are nausea, vomiting, paleness, and sweating in the exposed individual. Thus, the anti-motion sickness glasses were developed, which work using a fluid that moves in rings arranged around the eyes. This study protocol aims to evaluate the possibility that these glasses can avoid the sensory conflict that causes motion sickness, attenuating or eliminating the symptoms of motion sickness while reading in vehicles. Therefore, a crossover study shall be conducted, in which volunteers in two groups will travel in a standard car using antikinetosis goggles while reading, covering a predetermined path, in a trajectory that will last for 15 minutes. The first group (G1) will use functional glasses on the first day of testing. The second group (G2), in turn, will start the tests using the adulterated glasses, similar to the functional ones in appearance, but without the proposed effects of reducing or eliminating symptoms. On the second day of testing, for each group, the previously unused model will be employed instead. At the end of each clinical trial day, a questionnaire based in the MSSQ-Short shall be applied, evaluating the intensity of possible symptoms, their duration and the time till their appearance. Thus, the persistence of symptoms or the appearance of some clinical improvement will be evaluated, making it possible to verify the effectiveness of the object of study.

Comparison of Performance for Cochlear-Implant Listeners Using Audio Processing Strategies Based on Short-Time Fast Fourier Transform or Spectral Feature Extraction.

We compared sound quality and performance for a conventional cochlear-implant (CI) audio processing strategy based on short-time fast-Fourier transform (Crystalis) and an experimental strategy based on spectral feature extraction (SFE). In the latter, the more salient spectral features (acoustic events) were extracted and mapped into the CI stimulation electrodes. We hypothesized that (1) SFE would be superior to Crystalis because it can encode acoustic spectral features without the constraints imposed by the short-time fast-Fourier transform bin width, and (2) the potential benefit of SFE would be greater for CI users who have less neural cross-channel interactions. To examine the first hypothesis, 6 users of Oticon Medical Digisonic SP CIs were tested in a double-blind design with the SFE and Crystalis strategies on various aspects: word recognition in quiet, speech-in-noise reception threshold (SRT), consonant discrimination in quiet, listening effort, melody contour identification (MCI), and subjective sound quality. Word recognition and SRTs were measured on the first and last day of testing (4 to 5 days apart) to assess potential learning and/or acclimatization effects. Other tests were run once between the first and last testing day. Listening effort was assessed by measuring pupil dilation. MCI involved identifying a five-tone contour among five possible contours. Sound quality was assessed subjectively using the multiple stimulus with hidden reference and anchor (MUSHRA) paradigm for sentences, music, and ambient sounds. To examine the second hypothesis, cross-channel interaction was assessed behaviorally using forward masking. Word recognition was similar for the two strategies on the first day of testing and improved for both strategies on the last day of testing, with Crystalis improving significantly more. SRTs were worse with SFE than Crystalis on the first day of testing but became comparable on the last day of testing. Consonant discrimination scores were higher for Crystalis than for the SFE strategy. MCI scores and listening effort were not substantially different across strategies. Subjective sound quality scores were lower for the SFE than for the Crystalis strategy. The difference in performance with SFE and Crystalis was greater for CI users with higher channel interaction. CI-user performance was similar with the SFE and Crystalis strategies. Longer acclimatization times may be required to reveal the full potential of the SFE strategy.

HURRICANE KATRINA’S LASTING IMPACT ON YOUNGER AND OLDER ADULTS: THE ROLE OF RELIGIOSITY AND POSTTRAUMATIC GROWTH

Abstract In 2005, Hurricane Katrina devastated the U.S. Gulf Coast with catastrophic damage and substantial loss of life. In this study, we examined associations among psychosocial variables and mental health indicators in younger and older adults who lived in south Louisiana in August of 2005 when Katrina made landfall (M age = 51.7 years, SD = 13.03 years, age range: 32 to 78 years). All self-identified as African American / Black women. They were recruited through social media, flyers sent to churches and schools, and word of mouth referrals. On the first day of testing, participants completed sociodemographic, religiosity, and post-traumatic growth surveys and an adapted structured storm questionnaire (Cherry et al., 2011). On the second day of testing one week later, participants responded to open-ended questions on their Katrina experience, and they completed measures of post-traumatic stress disorder (PTSD) and depression. Correlation analyses revealed that age was inversely related to PTSD symptoms, which is compatible with an inoculation perspective on post-disaster psychological reactions. In addition, post-traumatic growth was positively correlated with religious beliefs and practices and religious coping, and negatively correlated with symptoms of PTSD and depression. Religious beliefs and practices were inversely correlated with PTSD symptoms and depression. Qualitative analyses of participants’ narrative responses indicated that some reflected on scripture and utilized prayer as a way to navigate their new lives in the years after Katrina. Implications of these data for understanding individual and community-level challenges in the years after exposure to devastating severe weather events are considered.

Uncharted territory: The feasibility of serial computerised cognitive assessment the first week post-stroke

BackgroundCognitive impairment is common and problematic post-stroke, yet vital information to understand early cognitive recovery is lacking. To examine early cognitive recovery, it is first necessary to establish the feasibility of repeat cognitive assessment during the acute post-stroke phase. ObjectiveTo determine if serial computerised testing is feasible for cognitive assessment in an acute post-stroke phase, measured by assessment completion rates. MethodAn observational cohort study recruited consecutive stroke patients admitted to an acute stroke unit within 48 hours of onset. Daily assessment with the Cambridge Neuropsychological Test Automated Battery (CANTAB) was performed for seven days, and single Montreal Cognitive Assessment (MoCA). ResultsSeventy-one participants were recruited, mean age 74 years, with 67 completing daily testing. Participants had predominantly mild (85%; NIHSS ≤6), ischemic (90%) stroke, 32% demonstrated clinical delirium. The first day of testing, 76% of participants completed CANTAB batteries. Eighty-seven percent of participants completed MoCA a mean of 3.4 days post-stroke. The proportion of CANTAB batteries completed improved significantly from day 2 to day 3 post-stroke with test completion rates stabilizing ≥ 92% by day 4. Participants with incomplete CANTAB were older, with persisting delirium, and longer stay in acute care. ConclusionSerial computerised cognitive assessments are feasible the first week post-stroke and provide a novel approach to measuring cognitive change for both clinical and research purposes. Maximum completion rates by day four have clinical implications for optimal timing of cognitive testing.

Feasibility of Specimen Self-collection in Young Children Undergoing SARS-CoV-2 Surveillance for In-Person Learning

There is an urgent need to assess the feasibility of COVID-19 surveillance measures in educational settings. To assess whether young children can feasibly self-collect SARS-CoV-2 samples for surveillance testing over the course of an academic year. This prospective pilot cohort study was conducted from September 10, 2020, to June 10, 2021, at a K-8 school in San Mateo County, California. The research consisted of quantitative data collection efforts: (1) demographic data collected, (2) student sample self-collection error rates, and (3) student sample self-collection time durations. Students were enrolled in a hybrid learning model, a teaching model in which students were taught in person and online, with students having the option to attend virtually as needed. Data were collected under waiver of consent from students participating in weekly SARS-CoV-2 testing. Errors over time for self-collection of nasal swabs such as contaminated swabs and inadequate or shallow swabbing; time taken for sample collection. Of 296 participants, 148 (50.0%) were boys and 148 (50.0%) were girls. A total of 87 participants (29.2%) identified as Asian; 2 (0.6%), Black or African American; 13 (4.4%), Hispanic/Latinx; 103 (34.6%), non-Hispanic White; 87 (29.2%), multiracial; and 6 (2.0%), other. The median school grade was fourth grade. From September 2020 to March 2021, a total of 4203 samples were obtained from 221 students on a weekly basis, while data on error rates were collected. Errors occurred in 2.7% (n = 107; 95% CI, 2.2%-3.2%) of student encounters, with the highest rate occurring on the first day of testing (20 [10.2%]). There was an overall decrease in error rates over time. From April to June 2021, a total of 2021 samples were obtained from 296 students on a weekly basis while data on encounter lengths were collected. Between April and June 2021, 193 encounters were timed. The mean duration of each encounter was 70 seconds (95% CI, 66.4-73.7 seconds). Mastery of self-collected lower nasal swabs is possible for children 5 years and older. Testing duration can be condensed once students gain proficiency in testing procedures. Scalability for larger schools is possible if consideration is given to the resource-intensive nature of the testing and the setting's weather patterns.

383. Feasibility of Specimen Self-collection in Young Children Undergoing SARS-CoV-2 Surveillance for In-person Learning

BackgroundWhile pediatric cases of COVID-19 are at low risk for adverse events, schoolchildren should be considered for surveillance as they can become infected at school and serve as sources of household or community transmission. Our team assessed the feasibility of young children self-collecting SARS-CoV-2 samples for surveillance testing in an educational setting.MethodsStudents at a K-8 school were tested weekly for SARS-CoV-2 from September 2020 - June 2021. Error rates were collected from September 2020 - January 2021. Clinical staff provided all students with instructions for anterior nares specimen self-collection and then observed them to ensure proper technique. Instructions included holding the sterile swab while making sure not to touch the tip, inserting the swab into their nostril until they start to feel resistance, and rubbing the swab in four circles before repeating the process in their other nostril. An independent observer timed random sample self-collections from April - June 2021.Results2,590 samples were collected from 209 students during the study period when data on error rates were collected. Errors occurred in 3.3% of all student encounters (n=87). Error rates over time are shown in Figure 1, with the highest rate occurring on the first day of testing (n=20/197, 10.2%) and the lowest in January 2021 (n=1/202, 0.5%). 2,574 visits for sample self-collection occurred during the study period when independent timing data was collected (April - June 2021). Of those visits, 7.5% (n=193) were timed. The average duration of each visit was 70 seconds.Figure 1. Swab Error Rates Over Time ConclusionPediatric self-collected lower nasal swabs are a viable and easily tolerated specimen collection method for SARS-CoV-2 surveillance in school settings, as evidenced by the low error rate and short time window of sample self-collection during testing. School administrators should expect errors to drop quickly after implementing testing. Disclosures All Authors: No reported disclosures

Particleboards from Recycled Thermally Modified Wood

In recent years, the production and consumption of thermally modified wood (TMW) has been increasing. Offcuts and other waste generated during TMWs processing into products, as well as already disposed products based on TMWs can be an input recycled raw material for production of particleboards (PBs). In a laboratory, 16 mm thick 3-layer PBs bonded with urea-formaldehyde (UF) resin were produced at 5.8 MPa, 240 °C and 8 s pressing factor. In PBs, the particles from fresh spruce wood and mixed particles from offcuts of pine, beech, and ash TMWs were combined in weight ratios of 100:0, 80:20, 50:50 and 0:100. Thickness swelling (TS) and water absorption (WA) of PBs decreased with increased portion of TMW particles, i.e., TS after 24 h maximally about 72.3% and WA after 24 h maximally about 64%. However, mechanical properties of PBs worsened proportionally with a higher content of recycled TMW—apparently, the modulus of rupture (MOR) up to 55.5% and internal bond (IB) up to 46.2%, while negative effect of TMW particles on the modulus of elasticity (MOE) was milder. Decay resistance of PBs to the brown-rot fungus Serpula lacrymans (Schumacher ex Fries) S.F. Gray increased if they contained TMW particles, maximally about 45%, while the mould resistance of PBs containing TMW particles improved only in the first days of test. In summary, the recycled TMW particles can improve the decay and water resistance of PBs exposed to higher humidity environment. However, worsening of their mechanical properties could appear, as well.

Clustering, morphology, and treatment resistance of Bacillus globigii spores recovered from a pilot-scale activated sludge system

This study examines the organization and morphology of Bacillus globigii (BG) spores, a common surrogate for Bacillus anthracis, which were seeded and then recovered at various times from several points within a conventional, pilot-scale activated sludge system. Recovered BG spores were enumerated, microscopically examined, and tested for resistance to chemical (i.e. 5% H2O2 for 8 min), thermal (80 °C for 30 min), and ultraviolet light (8 W, 254 nm UV for 1 min) inactivation. Spores exposed to activated sludge germinated, sporulated, and exhibited unique multilayer clustering patterns and statistically significant changes (p < 0.005) in dimensional morphology. Spores collected in the later experimental stages (i.e., during weeks 6 and 7) were significantly more resistant (p ≤ 0.05) to inactivation than those collected on the first day of testing. These results have direct consequences for sludge treatment requirements at wastewater treatment plants that receive spore-containing waste streams.

Inhibition of the biodiesel oxidation by alcoholic extracts of green and black tea leaves and plum pulp: Application of the simplex-centroid design

Abstract The efficiency of extracts with antioxidant properties of plum pulp, black tea and green tea leaves was evaluated, analyzing the induction periods (IP) and rate constants (k) at 110 °C, in the 1st, 30th, 57th an 91st day of storage. Antioxidant activity was observed in all extracts, either by the rat constant decreased or by the induction period increase. The higher induction period obtained was 9.15 h for the black tea leaves extract while the lower was 6.97 h for the green tea leaves extract. The control had an average induction period of 6.95 h for the first day. The models obtained are significant and showed determination coefficients greater than 0.90 with no significance lack of fit at the level of 5%. The optimization with maximization of the induction period and minimization of the rate constant showed that the black tea extract was the most suitable to avoid oxidation. On the first day of test, the optimization indicates the mixture containing 50% of black tea and 50% of plum pulp extract as the best mixture. The optimizations provided a variation of 8.92

Pengaruh Sudut Kemiringan Ruang Masak dan Penggunaan Lensa Fresnel terhadap Performa Kompor Surya Tipe Kotak

Performance test on box solar cooker with variations in the inclination angle of the cook room and variations of the cook room cover have been carried out. The variations angle of the cook room are 10°, 20° and 30° while the cook room cover uses 2 variations namely glass and a combination of fresnel glass. The size of the solar cooker is 60 x 60 x 40 cm with a thickness of 0.9 cm. The test was conducted in the car park behind the Engineering Building Politeknik Negeri Jember at 10:00 to 14:00 with recording every 10 minutes. The highest average solar cooker efficiency was found in solar cooker 4 with a cooking room tilt angle of 30° and using a fresnel glass combination cook room cover, the efficiency is 6.7% on the first day of testing. The highest average cooking power was also found in solar cooker 4 of 24.7 W on the second day of testing. The highest water suhue was found in solar cooker 4 at 90°C on the third day of testing.

Surface Modification of Lightweight Mortars by Nanopolymers to Improve Their Water-Repellency and Durability

The paper explores the possibility of covering the mortar with the lightweight aggregate by the nanopolymer silane and siloxane as surface hydrophobisation. The investigation involved the mortars with two types of hydrophobic agents diluted with water in a ratio of 1:4 and 1:8. Mortar wetting properties were determined by measuring the absorbability, water vapor diffusion, contact angle (CA) and surface free energy (SFE) of their structure. Surface micro-roughness and 2D topography were evaluated. Scanning electron microscopy (SEM) has shown the microstructure and distribution of pores in mortars. The reduction in absorbency after the first day of testing by 87% was shown. An improvement in frost resistance after 25 cycles by 97% and an 18-fold decrease in weight loss after the sulphate crystallization test were observed. The hydrophobic coating reduces the SFE of mortars and increases the CA. In the case of using silanes, a 9-fold increase CA was observed.

Practice day may be unnecessary prior to testing knee extensor strength in young healthy adults

ABSTRACT A practice session is common prior to strength testing. However, the benefits of practice have not been previously reported. The purpose of this study was to determine the effect of a practice session on peak torque, mean torque and between trial variability across three test days. We hypothesized that peak and mean torque would be higher and less variable the second and third test days than the first. Twenty-five healthy, young participants completed 3 maximal voluntary isometric and isokinetic knee extensions on three separate days. No difference in isometric torque was found between days 1 and 2, but there was a significant decrease in isokinetic torque (8.45 Nm). There was a significant decrease in both mean isometric and isokinetic torque from day 1 to day 3 (12.67 and 13.59 Nm). Contrary to our hypothesis, no benefit from a practice session was found. Healthy, young adults are able to produce peak knee extensor torques on the first day of testing and do not demonstrate any benefit from additional testing. Thus, a practice day preceding isometric and isokinetic knee extensor strength testing may not be necessary when testing healthy, young participants, and may, in fact, negatively impact subsequent strength measurements.

Влияние раннего провоспалительного стресса на тревожное и депрессивно-подобное поведение крыс разного возраста

An early proinflammatory stress produced by administration of LPS (50 mcg/kg, sc) on 3rd and 5th postnatal days led to decrease of locomotor and search activity and increase of anxiety in rats at the age of 1 month in the tests of an open field and elevated plus maze. The males showed more anxious behavior than females. Administration of LPS in early ontogenesis produced the signs of depressive-like behavior in males and females in the test of anhedonia by decrease of preference of 1% sucrose solution in comparison with control groups. The forced swimming test showed the signs of depressive-like behavior in males, but not in females at the first day of testing at the age of 1 month. At the age of 3 months the all mentioned changes in anxious and depressive-like behavior were practically disappeared. The data obtained point out to the sex differences in the effects of early proinflammatory stress on anxious and depressive-like behavior in rats.

Solar thermal drying plant for agricultural products. Part 1: Direct air heating system

The need for sustainability, food security and to decouple food prices from the fluctuating prices of finite fossil fuels have driven the search for sustainable processing and the adequate storage of agricultural products. For this reason, a hybrid thermo-solar monitoring plant for the dehydration of foods was successfully designed and built in Zacatecas, Mexico. The thermal energy is provided by a solar air heating system with 48 collectors (111.1 m2) and a solar water heating system with 40 water collectors (92.4 m2). The overall energy efficiency of the field of air heaters was 39.49% with a power capacity of 46.14 kW. A batch test was carried out with direct solar air heating system, in which 288 kg of Nopal (Opuntia ficus) was dehydrated with an initial and final moisture content of 93.03% and 5.76% (wet basis), respectively, which was achieved in 17.62 h, with a maximum theoretical thermal efficiency of the dryer of 60.7% recorded for the first day of testing. Two financial scenarios were used to evaluate the economic efficiency of the solar air heaters; a conventional scenario, comprising a 24-month payback period; and, a scenario with added fiscal incentives, comprising a 17-month payback period.

Abnormal empathy-like pro-social behaviour in the valproic acid model of autism spectrum disorder

Impairments in social behaviour are a defining feature of autism spectrum disorder (ASD). Individuals with ASD also usually present some difficulty to recognize or understand another person’s feelings. Therefore, it is possible that altered empathy processing could hinder typical social interaction in ASD. Recently, robust paradigms confirmed that rodents show primordial forms of empathy-like behaviour. Therefore, in this work, we used one of these new protocols to test pro-social behaviour in the rat model of autism induced by Valproic Acid (VPA). We also evaluated possible beneficial effects of Resveratrol, since it can prevent social deficits in the VPA model. Rats were tested on their ability to open a restrainer to release a trapped conspecific. Exposure to VPA precludes the timely manifestation of this empathy-like behaviour, but does not affect its continuation after its first expression. We also found a significant correlation between average speed during the first day of test and becoming an Opener. Similarly, rats able to open the restrainer on the first day had an increased likelihood of repeating this behaviour in the later days of the testing programme. We did not find any protective effects of Resveratrol. Further investigation of empathy-like behaviour in the VPA model and in other models of autism could help to clarify the behavioural and neural processes underpinning the basic aspects of empathy alterations in autistic individuals.

Reduction of Microbiota in Marinated Vacuum-Packaged Poultry Breast Fillets

A b s t r a c t: The aim of this study was to determine the effect of different marinade solution on the microbiome of chicken breast fillets packaged under vacuum and stored at 4°C. Three types of marinade were tested. A total of 120 chicken breast fillets were marinated in control (6% NaCl) or three different marinades: 6% NaCl and 2% sodium tripolyphosphate; 6% NaCl and 2% sodium citrate, and; 6% NaCl, 1% sodium tripolyphosphate and 1% sodium citrate. Microorganisms were enumerated on the first day of testing (day 0) and on days 7, 14, 21 and 28 of chilled storage. Marination resulted in significant differences (p<0.05) in the numbers of total viable counts, Enterobacteriaceae, lactic acid bacteria and anaerobic bacteria counts. The combination of 6% NaCl and 2% sodium citrate is the most appropriate marinade option for reducing the growth of the examined bacterial groups in vacuum-packaged marinated chicken breast fillets during chilled storage.

Extended Storage of Thawed Cryoprecipitate: Responsible and Rational Use of a Scarce Resource

BackgroundCryoprecipitate (cryo) is a frozen plasma derivative consisting of fibrinogen, factor (F) XIII, FVIII and von Willebrand factor (vWF), and was originally intended to replace FVIII in hemophilia. Today, cryo is primarily used as fibrinogen replacement in acquired coagulopathy related to trauma, obstetric hemorrhage, and DIC. Due to the lability of FVIII, guidelines mandate that cryo be given within 6 hours of thawing. Fibrinogen is much more stable; however, and these time constraints may unnecessarily contribute to delayed product utilization and increased waste. Viscoelastic assays are increasingly used to assess coagulopathy and may be better indicators of global coagulation function than standard coagulation assays. Here we evaluated the performance of thawed, refrigerated cryoprecipitate over extended storage times.MethodsCryo (six donor pools, n=8) was purchased from South Texas Blood and Tissue, thawed on first day of testing, and stored in aliquots refrigerated at 4°C for up to 35 days. Assays were performed in 37°C rewarmed product at baseline post-thaw and at 4, 24, and 72h, and then weekly to 35 days. Assays for factor levels were conducted in cryo diluted 1:10 in PBS and using a hematology analyzer (Stago) for fibrinogen and FVIII or by ristocetin cofactor assay (RCo) for vWF (Siemens). Coagulation and thrombin generation of stored cryo was tested in ROTEM and Calibrated Automated Thrombogram (CAT) by mixing cryo with frozen aliquots of cryo-poor plasma. A massive transfusion protocol (MTP) was simulated by combining cryo with red cells, fresh frozen plasma, and fresh apheresis platelets (1:1:1:1 ratio); this simulation was tested for coagulation with ROTEM and for vWF-mediated fluorescent-labeled platelet adhesion to collagen in a microfluidics flow system (Bioflux).ResultsIn simulated MTP, global coagulation function as measured by EXTEM and FIBTEM G-values from ROTEM were above normal reference ranges for whole blood for the entire 35d period (EXTEM smallest median G=13592 dyn/cm2, ref. range=4800-12250; FIBTEM smallest median G=2041, ref. range=495-1667). There was a slight decline in G value over storage duration, but it was not statistically significant (Fig 1). Lysis index at 30 min (LI30) in the EXTEM of simulated MTP did not statistically deviate over time (Fig 2).The MTP FIBTEM A10 value, shown to be correlated with fibrinogen concentration, remains high over 35 days, with only some values on D35 dropping into the normal range (Fig 3; means at D0=35.75mm and D35=26.63; ref. range=9-24). A10 and G were highly correlated (r=.812, p=.008).FVIII activity in cryo declined from 9-fold above average plasma levels over 35 days to approximately 25% of its starting activity. Surprisingly, the drop in FVIII was not correlated with clotting time (CT) in the EXTEM (r=-.335, p=.739), and CT was either faster than or within normal references ranges for whole blood at all time points (Fig 4; slowest median CT=49.5s, ref. range=42-72). The change in CT was correlated with measured peak thrombin levels (Fig 5; r=-.883, p=.002), although FVIII was not correlated with peak thrombin generation (r=.403, p=.282).vWF activity of cryo initially increased as has been previously reported but declined to baseline level by D7 and further through D35. vWF activity was correlated with the rate of platelet adhesion to a collagen surface under arterial flow (Fig 6; r=.677, p=.045).DiscussionCryo is mainly used in resuscitation of severe hemorrhage in MTP. It contributes to hemostasis by providing vWF to support platelet adhesion and primary hemostasis, FVIII to augment thrombin generation, and fibrinogen as clot substrate. Standard coagulation assays such as PT and aPTT or isolated factor activity assays are inadequate for evaluating the contribution of cryo to global MTP performance. The data presented here, derived from multiple functional tests including ROTEM, CAT, ristocetin cofactor assay, and Bioflux, show that thawed cryoprecipitate stored at 4°C is functionally viable for up to 35 days; as part of a massive transfusion protocol. It supports clot strength, thrombin generation, and platelet adhesion. Adoption of an extended shelf life for thawed cryo would reduce waste and increase availability for treatment of hemorrhage. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Validity and Repeatability of Single-Sensor Loadsol Insoles during Landing.

Clinically feasible methods for quantifying landing kinetics could help identify patients at risk for secondary anterior cruciate ligament injuries. The purpose of this study was to evaluate the validity and between-day repeatability of the loadsol insole during a single-hop and bilateral stop-jump. Thirty healthy recreational athletes completed seven single-hops and seven stop-jumps while simultaneous loadsol (100 Hz) and force plate (1920 Hz) measurements were recorded. Peak impact force, loading rate, and impulse were computed for the dominant limb, and limb symmetry was calculated between limbs for each measure. All outcomes were compared between the loadsol and force plate using intraclass correlation coefficients (ICC) and Bland–Altman plots. Fifteen participants completed a second day of testing to assess between-day repeatability of the loadsol. Finally, an additional 14 participants completed the first day of testing only to assess the validity of the newest generation loadsol, which sampled at 200 Hz. At 100 Hz, validity ICC results were moderate to excellent (0.686–0.982), and repeatability ICC results were moderate to excellent (0.616–0.928). The 200 Hz loadsol demonstrated improved validity ICC (0.765–0.987). Bland–Altman plots revealed that the loadsol underestimated load measures. However, this bias was not observed for symmetry outcomes. The loadsol device is a valid and repeatable tool for evaluating kinetics during landing.

Cocaine and cocaine expectancy increase growth hormone, ghrelin, GLP-1, IGF-1, adiponectin, and corticosterone while decreasing leptin, insulin, GIP, and prolactin

The dopamine system—essential for mood and movement—can be activated in two ways: by excitatory inputs that cause burst firing and stamp-in learning or by slow excitatory or inhibitory inputs—like leptin, insulin, ghrelin, or corticosterone—that decrease or increase single-spike (pacemaker) firing rate and that modulate motivation. In the present study we monitored blood samples taken prior to and during intravenous cocaine or saline self-administration in rats. During cocaine-taking, growth hormone and acetylated ghrelin increased 10-fold; glucagon-like peptide-1 (GLP-1) doubled; non-acetylated ghrelin, insulin-like growth factor-1 (IGF-1), and corticosterone increased by 50% and adiponectin increased by 17%. In the same blood samples, leptin, insulin, gastric inhibitory polypeptide (GIP), and prolactin decreased by 40–70%. On the first day of testing under extinction conditions—where the animals earned unexpected saline instead of cocaine—5-fold increases were seen for growth hormone and acetylated ghrelin and equal changes—in amplitude and latency—were seen in each of the other cases except for IGF-1 (which increased at a slower rate). Single-spike firing affects the tonic activation level of the dopamine system, involving very different controls than those that drive burst firing; thus, the present data suggest interesting new targets for medications that might be used in the early stages of drug abstinence.

REM sleep and safety signal learning in posttraumatic stress disorder: A preliminary study in military veterans

BackgroundPosttraumatic Stress Disorder (PTSD) is associated with a number of negative physical and mental health consequences. Fear conditioning plays an important mechanistic role in PTSD, and PTSD patients also show deficits in safety signal learning. Sleep, particularly REM sleep, is linked to improved safety learning and extinction processes in animal models and healthy humans. No studies have examined the link between REM sleep and safety signal learning or extinction memory in clinical populations. MethodsThis study examined the relationship between REM sleep, safety signal learning, and extinction processes in veterans with PTSD (n = 13). Patients' overnight sleep was characterized in the laboratory via polysomnography (PSG). The next day, participants underwent a fear conditioning paradigm during which they acquired fear toward a visual cue. This testing session also included a visual cue that became a safety signal (CS-). Following conditioning, the veterans' sleep was monitored overnight again, after which they underwent extinction training. Following a third night of sleep, extinction recall and safety recall were tested. Bivariate correlations examined the relationship between the slope of safety signal learning and subsequent REM sleep, as well as the relationship between REM sleep and subsequent extinction recall and safety recall on the last day of testing. ResultsVeterans learned to differentiate the CS+ and the CS- on the first day of testing. Veterans who underwent safety learning more quickly on the first day of testing showed more efficient REM sleep that night (r = .607, p = .028). On the second day of testing, the patients successfully underwent extinction learning. Patients with a higher percentage of REM sleep on the last night of the study showed more safety recall early on the last day of testing (r = .688, p = .009). ConclusionTo our knowledge, this was the first study to examine the relationship between objective sleep and fear-potentiated startle performance in veterans with PTSD. Study methods were well tolerated by participants, supporting feasibility of the experimental design. Results indicated REM sleep was associated with both initial safety learning and subsequent safety recall. Taken together with previous studies in healthy controls, these preliminary results provide additional evidence suggesting REM sleep could play a mechanistic role in the maintenance of PTSD and thus identify a modifiable biological process to target in treatment of PTSD. These findings should be replicated in larger samples.