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Introduction: Prognostication is a significant challenge early in the post-cardiac arrest period. Common prognostic factors for neurological survival are unreliable (high false positive rates) until 72 hours post-cardiac arrest. It is not known whether there are a combination of factors that can be utilized earlier in the post-cardiac arrest period to accurately predict patient outcome. Our objective was to predict neurological outcome utilizing a novel combination of patient factors early in the post-cardiac arrest period. Methods: We conducted a retrospective cohort study using data from our local cardiac arrest registry. We included adult patients who obtained a return of spontaneous circulation (ROSC) after out-of-hospital cardiac arrest (OHCA). We excluded patients who did not survive for at least 24 hours post-ROSC and those who had a do not resuscitate (DNR) order within 2 hours of ROSC. We performed an ordinal regression analysis using the proportional odds model to predict neurological outcome (modified rankin score (mRS)). We included a good neurological outcome (mRS 0-2), poor neurological outcome (mRS 3-5), and dead (mRS 6) as an ordinal outcome. We included a number of patient demographics, intra- and post-cardiac arrest factors as covariates in our model. The predictive performance of our model was analyzed using receiver operating characteristic (ROC) curves for discrimination and Brier statistic for calibration. Results: We included 3448 patients in our analysis. We found that an initial shockable rhythm (odds ratio (OR) 4.1; 95% confidence interval (CI) 3.6, 5.4), the absence of pupillary reflexes (OR 3.5; 95% CI 2.4,4.8) and maximum motor score on the Glasgow Coma Scale (GCS) (OR 1.5; 95% CI 1.4,1.6) had the greatest association with improved neurologic outcome. Longer duration of resuscitation was associate with worse outcomes (OR 0.84, 95% CI 0.82,0.87). The overall performance of our model was excellent with an area under the ROC curve of 0.89 and a Brier statistic of 0.13. Conclusion: Our model predicted good neurological outcome with a high rate of accuracy, however external validation of the model is required. This model may be useful in providing initial risk stratification of patients in clinical practice and future research on post-cardiac arrest care.
Introduction: Despite recent advances in resuscitation, some patients remain in ventricular fibrillation (VF) after multiple defibrillation attempts during out-of-hospital cardiac arrest (OHCA). Vector change defibrillation (VC) and double sequential external defibrillation (DSED) have been proposed as alternate therapeutic strategies for OHCA patients with refractory VF. The primary objective was to determine the feasibility, safety and sample size required for a future cluster randomized controlled trial (RCT) with crossover comparing VC or DSED to standard defibrillation for patients experiencing refractory VF. Secondary objectives were to evaluate the intervention effect on VF termination and return of spontaneous circulation (ROSC). Methods: We conducted a pilot cluster RCT with crossover in four Canadian paramedic services and included all treated adult OHCA patients who presented in VF and received a minimum of three defibrillation attempts. In addition to standard cardiac arrest care, each EMS service was randomly assigned to provide continued standard defibrillation (control), VC or DSED. Services crossed over to an alternate defibrillation strategy after six months. Prior to the launch of the trial, 2,500 paramedics received in-person training for VC and DSED defibrillation using a combination of didactic, video and simulated scenarios. Results: Between March 2018 and September 2019, 152 patients were enrolled. Monthly enrollment varied from 1.4 to 6.1 cases per service. With respect to feasibility, 89.5% of cases received the defibrillation strategy they were randomly allocated to, and 93.1% of cases received a VC or DSED shock prior to the sixth defibrillation attempt. There were no reported cases of defibrillator malfunction, skin burns, difficulty with pad placement or concerns expressed by paramedics, patients, families, or ED staff about the trial. In the standard defibrillation group, 66.6% of cases resulted in VF termination, compared to 82.0% in VC and 76.3% of cases in the DSED group. ROSC was achieved in 25.0%, 39.3% and 40.0% of standard, VC and DSED groups, respectively. Conclusion: Findings from our pilot RCT suggest the DOSE VF protocol is feasible and safe. VF termination and ROSC were higher with VC and DSED compared to standard defibrillation. The results of this pilot trial will allow us to inform a multicenter cluster RCT with crossover to determine if alternate defibrillation strategies for refractory VF may impact patient-centered, clinical outcomes
The European Prediction of Psychosis Study (EPOS) aimed to study a large sample of young patients who are at risk of psychosis and to estimate their conversion rate to psychosis during 18 months follow-up. This presentation describes quality of life and its changes in patients at risk of psychosis.
In six European centres, 16 to 35 year old psychiatric patients were examined. Risk of psychosis was defined by occurrence of basic symptoms, attenuated psychotic symptoms, brief, limited or intermittent psychotic symptoms or familial risk plus reduced functioning. Quality of life (QoL), measured by the Modular System for Quality of Life, was assessed at baseline and at 9 and 18 months’ follow-ups. Psychiatric patients without prodromal symptoms and healthy subjects were comparison groups.
In all, 245 risk patients were included. At baseline, they reported lower QoL than non-risk patients and healthy controls. Basic symptoms associated negatively with QoL, and there were differences between the study centres. During the follow-up, QoL raised less in risk patients than in non-risk patients. Baseline QoL did not predict transition to psychosis. However, its development was poorer in patients with than in those without transition to psychosis.
Those of the psychiatric patients who are at risk of psychosis have lower QoL than other psychiatric patients or healthy controls. QoL does not predict transition to psychosis, but its changes correlates with changes in clinical state. The results indicate that there is a need for comprehensive intervention with the patients at risk of psychosis.
Both schizophrenia and ultra high risk (UHR) patients show reduced neurocognitive performance compared to matched healthy control subjects. In the current study we compared neurocognitive performance at baseline and follow up between UHR patients who made the transition to psychosis and patients who did not.
Patients were eligible for the study when they met criteria for one or more of the following groups: Attenuated symptoms or brief limited intermitted psychotic symptoms or a first degree family member with a psychotic disorder and reduced functioning or basic symptoms. We assessed 216 UHR patients (166 males, mean age: 22,6 SD 5,2) with a neuropsychological test battery composed of the National adult reading test (premorbid IQ), California verbal memory test (verbal memory), spatial working memory test, verbal fluency first letter and categories (executive functioning), finger tapping test (motor speed) and continuous performance test (sustained attention). Data were collected in 7 participating centres of EPOS. Follow up was at 9 months.
37 UHR patients made the transition to psychosis (25 males, mean age 21,5 SD 4,8). The only test that showed a significant difference between the transition and non transition group at baseline was verbal fluency categories (t= 2.79, p = 0.006).
Patients who later make the transition to psychosis perform significantly worse on verbal fluency categories than patients who do not make the transition to psychosis. Verbal fluency may contribute to an improved prediction of psychosis in UHR patients. Follow up results will also be presented.
It has long been known that cannabis can elicit an acute psychotic reaction. Recent work shows that, of the 60 cannabinoid molecules in the plant, delta-9-tetrahydrocannibinol is responsible for the central effects of cannabis. Here we aimed to investigate, in more detail, the psychological effects of synthetic intravenous THC in healthy subjects. Over 2 experimental sessions, participants (N=22) were administered 2.5mg IV THC or placebo under randomised, double-blind conditions. Psychological reactions were assessed using standard rating instruments and a battery of cognitive tests was completed.
Following THC, there was a significant increase in self-rated and observer-rated positive psychotic symptoms which were highly correlated (r=0.62, p=0.001).Phenomena centered on de-synchronisation of self-agency (ipseity disturbance) and hypersalience/paranoia. Participants also reported a significant increase in negative symptomatology under THC conditions, which was not explained by sedation. Finally, working memory/executive functioning was markedly and consistently impaired by THC.
Here we provide further evidence that THC can elicit an acute psychotic reaction in a proportion of healthy subjects. Acute THC-psychosis elicits positive, negative and cognitive symptoms. Compared with other drug models THC recreates symptomatology across 3 major dimensions of schizophrenic psychosis without sedation/clouding of consciousness. Here we also present preliminary evidence that the molecule cannabidiol (CBD) inhibits THC-elicited positive symptoms. Current work in our laboratory is exploring the underlying mechanisms.
This guidance paper from the European Psychiatric Association (EPA) aims to provide evidence-based recommendations on early intervention in clinical high risk (CHR) states of psychosis, assessed according to the EPA guidance on early detection. The recommendations were derived from a meta-analysis of current empirical evidence on the efficacy of psychological and pharmacological interventions in CHR samples. Eligible studies had to investigate conversion rate and/or functioning as a treatment outcome in CHR patients defined by the ultra-high risk and/or basic symptom criteria. Besides analyses on treatment effects on conversion rate and functional outcome, age and type of intervention were examined as potential moderators. Based on data from 15 studies (n = 1394), early intervention generally produced significantly reduced conversion rates at 6- to 48-month follow-up compared to control conditions. However, early intervention failed to achieve significantly greater functional improvements because both early intervention and control conditions produced similar positive effects. With regard to the type of intervention, both psychological and pharmacological interventions produced significant effects on conversion rates, but not on functional outcome relative to the control conditions. Early intervention in youth samples was generally less effective than in predominantly adult samples. Seven evidence-based recommendations for early intervention in CHR samples could have been formulated, although more studies are needed to investigate the specificity of treatment effects and potential age effects in order to tailor interventions to the individual treatment needs and risk status.
The European Prediction of Psychosis Study (EPOS) involved a large (n=245) sample of young individuals at high-risk of developing psychosis. Participants appraisals of criticism and emotional over-involvement were described employing the Level of Expressed Emotion (LEE) measure. This presentation explores results and implications over an 18 month follow-up period.
Across six European centres, n=245 patients aged 16 – 35 years and ascertained to be at high-risk of developing psychosis were assessed over a period of eighteen months. Risk of psychosis was defined by occurrence of basic symptoms, attenuated psychotic symptoms, brief, limited or intermittent psychotic symptoms or familial risk plus reduced functioning. Appraisals of familial expressed emotion from participants towards key family members were examined for relationships to risk of transition to psychosis, psychotic symptomatology and demographical data.
Individuals at high-risk of psychosis were included and compared on the five sub-scales of LEE. Levels of Criticism, Irritability, Intrusiveness and Lack of emotional support were examined with significant correlations found between patient-perceived intrusive over-involvement and depression as well as between sub-scales of LEE and positive symptoms of psychosis. Transition to psychosis was not predicted by LEE in participants.
Perceived LEE of significant others by individuals at high-risk of developing psychosis may have a role in the maintenance of both affective and positive psychotic symptoms prior to the onset of full psychosis. Further explorations of the impact of EE appraisal on developing psychotic symptoms may inform potential targets for therapeutic intervention in both at-risk individuals and family members.
The aim of this guidance paper of the European Psychiatric Association is to provide evidence-based recommendations on the early detection of a clinical high risk (CHR) for psychosis in patients with mental problems. To this aim, we conducted a meta-analysis of studies reporting on conversion rates to psychosis in non-overlapping samples meeting any at least any one of the main CHR criteria: ultra-high risk (UHR) and/or basic symptoms criteria. Further, effects of potential moderators (different UHR criteria definitions, single UHR criteria and age) on conversion rates were examined. Conversion rates in the identified 42 samples with altogether more than 4000 CHR patients who had mainly been identified by UHR criteria and/or the basic symptom criterion ‘cognitive disturbances’ (COGDIS) showed considerable heterogeneity. While UHR criteria and COGDIS were related to similar conversion rates until 2-year follow-up, conversion rates of COGDIS were significantly higher thereafter. Differences in onset and frequency requirements of symptomatic UHR criteria or in their different consideration of functional decline, substance use and co-morbidity did not seem to impact on conversion rates. The ‘genetic risk and functional decline’ UHR criterion was rarely met and only showed an insignificant pooled sample effect. However, age significantly affected UHR conversion rates with lower rates in children and adolescents. Although more research into potential sources of heterogeneity in conversion rates is needed to facilitate improvement of CHR criteria, six evidence-based recommendations for an early detection of psychosis were developed as a basis for the EPA guidance on early intervention in CHR states.
A main objective of EPOS is to provide a valid multifactorial model for the prediction of psychosis. One major element of such a model should be the clinical state.
In a European multicentre study, persons fulfilling clinical criteria thought to indicate an increased risk for psychosis (PAR) were assessed amongst others with different psychopathological instruments covering the whole spectrum from basic symptoms to frank psychotic symptoms. Inclusion criteria comprised attenuated positive symptoms (APS), brief limited intermittent psychotic symptoms (BLIPS), cognitive basic symptoms (CogDis) and a combination of family risk and reduced functioning (S&T).
246 PAR were included into the study, mostly by APS or CogDis. Analysis of demographical data showed a high amount of functional impairment, resulting e.g. in low mean GAF scores (51.0 ± 11.8 SD), and of non-psychotic axis-I disorders. In September 2006, the hazard rate for a conversion to psychosis was 15.3 at 12 and 20.0 at 18 months after baseline assessment. According to the inclusion criteria, the highest rate of conversion was observed among PAR with BLIPS. On a dimensional level, a low GAF score was among the best predictors of conversion.
The transition rates of EPOS were in line with recent studies. A first analysis of clinical data supports the notion that the functional state should be an inherent part of any set of clinical risk criteria. Further analysis will consider the contribution of single symptoms or symptom combinations and the impact of symptom duration.
One aim of the European prediction of psychosis study (EPOS) has been to evaluate the clinical course of putatively prodromal patients in terms of psychopathology.
245 patients at risk for psychosis defined by attenuated positive symptoms, brief limited psychotic symptoms, a state/ trait combination or cognitive-perceptive basic symptoms was recruited in six centres in four countries. The Structured Interview for Prodromal Syndromes (SIPS) and the Bonn Scale for the Assessment of Basic Symptoms – Prediction List (BSABS-P) were employed. Follow-up was scheduled after 9 months (t1) and 18 months.
In total, 40 patients developed a psychosis (P). Compared to those without a transition (NP), P showed significantly higher SIPS scores at baseline. The same applied to the BSABS-P sub-scores 'cognitive perception disturbances' and 'cognitive motor disturbances'. The P sub-group developing psychosis after t1 showed no significant change of the SIPS positive (SIPS-P) sub-score or of any BSABS-P score from baseline to t1, whereas all scores improved in the NP group. At t1, SIPS-P and BSABS-P sub-score 'cognitive thought disturbances' were significantly lower in those later becoming psychotic.
Patients at risk showing a transition to psychosis during exhibited a pronounced psychopathology at baseline. Also, the positive symptom scores did not significantly improve during 1st follow-up, whereas those patients with no transition during the complete follow-up showed an improvement of all scores. As EPOS is a naturalistic study, different treatments have been performed in a considerable portion of the patients and association with course awaits further analysis.
The placenta develops alongside the embryo and fetus and is responsible for fetal gas exchange and nutrition. The placenta also has important immune and endocrine functions and thus undertakes to fulfill the roles played by various somatic organs in the post-natal situation (Figure 5.1). The placental membrane, the chorion, prevents the fetal and maternal blood from mixing, while allowing transport of molecules. The human placenta is haemochorial, which means that maternal blood contacts the chorionic placental membrane (fetal epitheliem).
Currently no national guidelines exist for the management of scabies outbreaks in residential or nursing care homes for the elderly in the United Kingdom. In this setting, diagnosis and treatment of scabies outbreaks is often delayed and optimal drug treatment, environmental control measures and even outcome measures are unclear. We undertook a systematic review to establish the efficacy of outbreak management interventions and determine evidence-based recommendations. Four electronic databases were searched for relevant studies, which were assessed using a quality assessment tool drawing on STROBE guidelines to describe the quality of observational data. Nineteen outbreak reports were identified, describing both drug treatment and environmental management measures. The quality of data was poor; none reported all outcome measures and only four described symptom relief measures. We were unable to make definitive evidence-based recommendations. We draw on the results to propose a framework for data collection in future observational studies of scabies outbreaks. While high-quality randomised controlled trials are needed to determine optimal drug treatment, evidence on environmental measures will need augmentation through other literature studies. The quality assessment tool designed is a useful resource for reporting of outcome measures including patient-reported measures in future outbreaks.
Poor performance and ill-health of calves in the pre-wean period can affect future productivity. Increasing numbers of producers are opting to use calf jackets as a means of mitigating the potential negative effects of low ambient temperatures, wind speed and precipitation on growth and health. This study aimed to use a range of noninvasive monitoring technologies to investigate the effects of using calf jackets in the first 3 weeks of life on calf performance and behavioural and physiological parameters. Ninety Holstein-Friesian calves were allocated to one of the two treatments: (i) Jacketed until 21 days of age and (J; n = 44) ii. Nonjacketed (NJ; n = 46). Calves were group housed and fed milk replacer (MR) and concentrate solid feed via automatic feeders. Calves were weaned at day 56, and the experiment was completed at day 63. Health assessments were conducted on a daily basis throughout the experiment using predefined faecal and respiratory scoring protocols. A range of novel, noninvasive monitoring technologies were used to examine the activity, heart rate and thermal profiles of calves on an individual basis throughout the experimental period. There were no differences in calf live weight (LWT), average daily gain (ADG) or feed conversion efficiency (FCE) in J and NJ calves between days 5 to 20. However, NJ calves consumed more MR and had more unrewarded visits to the milk feeder than J calves during this period. Although calf LWT was comparable across treatments in the week following jacket removal (days 21 to 28), both ADG and FCE tended to be greater in NJ calves. There were no treatment differences in calf LWT at the end of the study (d63). When measured over a period of 24 h and at a mean ambient temperature of 7.7°C, skin surface temperature was 6.37°C higher in J calves. Core body temperature was higher in J calves between days 5 to 20; however, there were no differences in IR eye or IR rectal temperature. No differences in lying behaviour occurred, with calves spending 18 and 17 h/day lying between days 5 to 20 and days 21 to 28, respectively. Under the climatic and management conditions described, no significant benefits to calf performance were found as a result of the provision of calf jackets to group-housed calves in the first 3 weeks of life. The higher frequency of unrewarded visits to the milk feeder in NJ calves during the first 3 weeks of life could be suggestive of a lack of satiety in these calves.
Introduction: Despite significant advances in resuscitation efforts, there are some patients who remain in ventricular fibrillation (VF) after multiple shocks during out-of-hospital cardiac arrest (OHCA). Double sequential external defibrillation (DSED) has been proposed as a treatment option for patients in shock refractory VF. We sought to compare DSED to standard therapy with regards to VF termination and return of spontaneous circulation (ROSC) for patients presenting in shock refractory VF. Methods: We performed a retrospective review of all treated adult OHCA who presented in VF and received a minimum of three successive shocks over a two year period beginning on Jan 1, 2015 in four Canadian EMS agencies. Using ambulance call reports and defibrillator files, we compared VF termination (defined as the absence of VF at the rhythm check following defibrillation and 2 minutes of CPR) and VF termination into a perfusing rhythm with ROSC between patients who received standard therapy (CPR, defibrillation, epinephrine and antiarrhythmics) and those who received DSED (after on-line medical consultation) for shock refractory VF. Cases of traumatic cardiac arrest and those who presented in VF but terminated VF prior to 3 successive shocks were excluded. Results: Among 197 patients who met the study criteria for shock refractory VF, 161 (81.7%) patients received standard therapy and 36 (18.3%) received DSED. For the primary outcome, VF termination was significantly higher for DSED compared to standard therapy (63.9% vs 18.0%; Δ45.9%; 95% CI: 28.3 to 60.5). For the secondary outcome of VF termination into ROSC, DSED was associated with significantly higher ROSC compared to standard care (33.3% vs 13%; Δ20.3%; 95% CI:13.0 to 33.3). The median (IQR) number of failed standard shocks prior to DSED was 8 (6, 10). When DSED terminated VF, it did so with a single DSED shock in 69.6% of cases. Conclusion: Our observational findings suggest improved VF termination and ROSC are associated with DSED compared to standard therapy for shock refractory VF. An appropriately powered randomized controlled trial is required to assess the impact of DSED on patient-important outcomes.
Introduction: 9-1-1 telecommunicators receive minimal education on agonal breathing, often resulting in unrecognized out-of-hospital cardiac arrest (OHCA). We successfully piloted an educational intervention that significantly improved telecommunicators’ OHCA recognition and bystander CPR rates in Ottawa. We sought to better understand the operations of Canadian 9-1-1 communications centers (CC) in preparation for a multi-centre study of this intervention. Methods: We conducted a National survey of all Canadian CCs. Survey domains included information on organizational structure, dispatch system used, education curriculum, and performance monitoring. It was peer-reviewed, translated in French, pilot-tested, and distributed electronically using a modified Dillman method. We designated respondents in each CC before distribution and used targeted follow-up and small incentives to increase response rate. Respondents also described functioning of neighboring CCs if known. Results: We received information from 51/51 provincial and 1/25 territorial CCs, representing 99.7% of the Canadian population. CCs largely utilize the Medical Dispatch Priority System (MPDS) platform (93%), many are Province/Ministry regulated (50%) and most require a High School diploma as minimum entry level education (78%). Telecommunicators receive initial in-class training (median 1.3 months, IQR 0.3-1.9; range 0.1-2.2), often followed by a preceptorship (84.4%) (median 1.0 months, IQR 0.7-1.7; range 0.4-6.0). Educational curriculum includes information on agonal breathing in 41% of CC, without audio examples in 34%. Among responding CCs, over 39,000 suspected OHCA 9-1-1 calls are received annually. Few CCs maintain local performance statistics on OHCA recognition (25%), bystander CPR rates (25%) or survival rates (50%). Most (97%) expressed interest in future research collaborations. Conclusion: Most Canadian telecommunicators receive no or minimal education in recognizing agonal breathing. Further training and improved OHCA monitoring may assist recognition and enhance outcomes.
Early life experiences can affect social behaviour in later life, but opportunities for socio-behavioural development are often overlooked in current husbandry practices. This experiment investigated the effects of rearing piglets in two-stage group lactation (GL) system from 7 or 14 days of age on piglet aggression at weaning. Three lactation housing treatments were applied to a total of 198 piglets from 30 litters of multiparous sows. All dams farrowed in standard farrowing crates (FCs). Group lactation litters were transferred with their dam at 7 (GL7) or 14 days (GL14) postpartum to GL pens (one pen of five sows at 8.4 m2/sow and one pen of seven sows at 8.1 m2/sow, per GL treatment). Farrowing crate litters remained with their dam in a single litter until weaning. At weaning, 10 to 14 piglets from two unfamiliar litters from the same housing treatment were mixed into pens (n=5 pens/treatment) and their behaviour was continuously recorded for 3.5 h. For each pen, the frequency of aggressive bouts (reciprocal and non-reciprocal aggression lasting <5 s), the frequency and duration of fights (reciprocal aggression lasting ⩾5 s) and bullying events (non-reciprocal aggression lasting ⩾5 s) were recorded, along with whether interactions involved familiar or unfamiliar piglets. Aggressive bouts delivered by FC piglets were approximately 1.5 and 3.0 times more frequent than that delivered by GL7 and GL14 piglets, respectively (40.5, 16.7 and 9.9 bouts/pig, respectively; P<0.05). Fighting was more frequent (1.6, 0.3 and 0.4 fights/pig, respectively; P<0.001) and fights were longer (83, 15 and 32 s fight/pig, respectively; P<0.001) between FC piglets than between GL7 or GL14 piglets. Bullying did not differ between housing treatments (P>0.05). GL7 and GL14 piglets engaged in a similar number of fights with unfamiliar as familiar piglets, but FC piglets had almost three times as many fights with unfamiliar than with familiar piglets (P<0.05). This experiment confirms the benefits of GL housing for pig social development. Further investigation is required to determine whether mixing before 14 days postpartum has implications for other indicators of animal welfare and productivity in a two-stage GL housing system.
Loose farrowing pens have been considered as alternatives to crates to enhance sow welfare. A major concern with pen systems is often higher piglet pre-weaning mortality, especially due to crushing by the sow. An optimal management of light and mat surface temperature may promote greater piglet use of the creep, which has been associated with reduced piglet crushing. A total of 108 sows and their piglets were studied in sow welfare and piglet protection pens on a commercial piggery, across two replicates. Sows were randomly assigned to pens arranged within two creep treatments (bright creep: 300 lx v. dark creep: 4 lx), considering mat temperature as a covariate. Twelve sows and their litters in each treatment (24 in total) had their behaviour continuously recorded for 72-h postpartum (pp), and four focal piglets per litter were weighed on the first and third days pp. In situ behaviour observations were performed daily (from 0800 to 1700 h) on all sows and their litters, every 15 min over 72-h pp to record piglet time spent in the creep, latency to enter the creep for the first time, latency for the litter to remain in the creep for at least 10 min, and piglet and sow use of pen areas immediately in front of (A2) and farthest from the creep (A3). Piglets with access to bright creeps spent on average 7.2% more time (P<0.01) in the creeps than piglets in pens with Dark creeps. In addition, for each degree increase in mat temperature, piglets spent on average 2.1% more time (P<0.01) in the creep. Piglets in pens with bright creeps spent less time in A2 (P=0.04) and the least time in A3 (P=0.01). Light or mat temperature did not affect sow use of pen areas or piglet weight gain. Piglets with bright creeps tended (P=0.06) to take longer to enter the creep for the first time after birth, but the latency for 30.0% of the litter to remain clustered for 10 min tended (P=0.08) to be shorter in bright compared to dark creeps. Overall, piglet use of the creep increased with warm mat temperatures and brightness, which should be further investigated as potential strategies to promote piglet safety and reduce crushing in pen farrowing systems.
High-intensity laser–plasma interactions produce a wide array of energetic particles and beams with promising applications. Unfortunately, the high repetition rate and high average power requirements for many applications are not satisfied by the lasers, optics, targets, and diagnostics currently employed. Here, we aim to address the need for high-repetition-rate targets and optics through the use of liquids. A novel nozzle assembly is used to generate high-velocity, laminar-flowing liquid microjets which are compatible with a low-vacuum environment, generate little to no debris, and exhibit precise positional and dimensional tolerances. Jets, droplets, submicron-thick sheets, and other exotic configurations are characterized with pump–probe shadowgraphy to evaluate their use as targets. To demonstrate a high-repetition-rate, consumable, liquid optical element, we present a plasma mirror created by a submicron-thick liquid sheet. This plasma mirror provides etalon-like anti-reflection properties in the low field of 0.1% and high reflectivity as a plasma, 69%, at a repetition rate of 1 kHz. Practical considerations of fluid compatibility, in-vacuum operation, and estimates of maximum repetition rate are addressed. The targets and optics presented here demonstrate a potential technique for enabling the operation of laser–plasma interactions at high repetition rates.