Relationship between different sources of non-protein nitrogen and supplementation times on performance and metabolism of grazing Nellore cattle during the dry season.

Two experiments were conducted to evaluate the effect of supplementation with two sources of non-protein nitrogen at different feeding times on the performance, ingestive behavior, and rumen metabolism of growing Nellore bulls during the dry season. Exp. 1: One hundred and twenty Nellore bulls, weighing 206 ± 39 kg of initial body weight (BW) and 12 months of age, were divided into 20 paddocks, and they were used in randomized block design in a 2 × 2 factorial arrangement to evaluate performance and ingestive behavior. Exp. 2: 12 rumen cannulated animals with 509 ± 59 BW, divided into 4 paddocks, were used in a triple Latin square 4 × 4 in a 2 × 2 factorial arrangement to evaluate metabolism. The factors were 2 non-protein nitrogen sources (urea or slow-release urea) and 2 feeding times (07:00 or 13:00 at 4 g/kg BW of supplement). There was no influence of non-protein sources, supplementation time, or their interaction on the grazing time or the trough time during daytime, nighttime, or total (P ≥ 0.16). There were no interactions or factor effects on ADG (P ≥ 0.45) or final body weight (P ≥ 0.39). There was an interaction between supplementation time and collection time (P < 0.01) on ruminal pH. Animals supplemented in the morning had greater total SCFA at 18 h after supplementation (P = 0.03). The supplementation time and the non-protein nitrogen sources did not alter the ingestive behavior or animal performance of young Nellore cattle.

Improved Constraints on Global Methane Emissions and Sinks Using δ 13C-CH4.

We study the drivers behind the global atmospheric methane (CH4) increase observed after 2006. Candidate emission and sink scenarios are constructed based on proposed hypotheses in the literature. These scenarios are simulated in the TM5 tracer transport model for 1984-2016 to produce three-dimensional fields of CH4 and δ 13C-CH4, which are compared with observations to test the competing hypotheses in the literature in one common model framework. We find that the fossil fuel (FF) CH4 emission trend from the Emissions Database for Global Atmospheric Research 4.3.2 inventory does not agree with observed δ 13C-CH4. Increased FF CH4 emissions are unlikely to be the dominant driver for the post-2006 global CH4 increase despite the possibility for a small FF emission increase. We also find that a significant decrease in the abundance of hydroxyl radicals (OH) cannot explain the post-2006 global CH4 increase since it does not track the observed decrease in global mean δ 13C-CH4. Different CH4 sinks have different fractionation factors for δ 13C-CH4, thus we can investigate the uncertainty introduced by the reaction of CH4 with tropospheric chlorine (Cl), a CH4 sink whose abundance, spatial distribution, and temporal changes remain uncertain. Our results show that including or excluding tropospheric Cl as a 13 Tg/year CH4 sink in our model changes the magnitude of estimated fossil emissions by ∼20%. We also found that by using different wetland emissions based on a static versus a dynamic wetland area map, the partitioning between FF and microbial sources differs by 20 Tg/year, ∼12% of estimated fossil emissions.

The anatomy of past abrupt warmings recorded in Greenland ice.

Data availability and temporal resolution make it challenging to unravel the anatomy (duration and temporal phasing) of the Last Glacial abrupt climate changes. Here, we address these limitations by investigating the anatomy of abrupt changes using sub-decadal-scale records from Greenland ice cores. We highlight the absence of a systematic pattern in the anatomy of abrupt changes as recorded in different ice parameters. This diversity in the sequence of changes seen in ice-core data is also observed in climate parameters derived from numerical simulations which exhibit self-sustained abrupt variability arising from internal atmosphere-ice-ocean interactions. Our analysis of two ice cores shows that the diversity of abrupt warming transitions represents variability inherent to the climate system and not archive-specific noise. Our results hint that during these abrupt events, it may not be possible to infer statistically-robust leads and lags between the different components of the climate system because of their tight coupling.

Evidence of Isotopic Fractionation During Vapor Exchange Between the Atmosphere and the Snow Surface in Greenland.

Several recent studies from both Greenland and Antarctica have reported significant changes in the water isotopic composition of near-surface snow between precipitation events. These changes have been linked to isotopic exchange with atmospheric water vapor and sublimation-induced fractionation, but the processes are poorly constrained by observations. Understanding and quantifying these processes are crucial to both the interpretation of ice core climate proxies and the formulation of isotope-enabled general circulation models. Here, we present continuous measurements of the water isotopic composition in surface snow and atmospheric vapor together with near-surface atmospheric turbulence and snow-air latent and sensible heat fluxes, obtained at the East Greenland Ice-Core Project drilling site in summer 2016. For two 4-day-long time periods, significant diurnal variations in atmospheric water isotopologues are observed. A model is developed to explore the impact of this variability on the surface snow isotopic composition. Our model suggests that the snow isotopic composition in the upper subcentimeter of the snow exhibits a diurnal variation with amplitudes in δ18O and δD of ~2.5‰ and ~13‰, respectively. As comparison, such changes correspond to 10-20% of the magnitude of seasonal changes in interior Greenland snow pack isotopes and of the change across a glacial-interglacial transition. Importantly, our observation and model results suggest, that sublimation-induced fractionation needs to be included in simulations of exchanges between the vapor and the snow surface on diurnal timescales during summer cloud-free conditions in northeast Greenland.

Effects of removing woody cover on long-term population dynamics of a rare annual plant (Agalinis auriculata): A study comparing remnant prairie and oldfield habitats.

Worldwide, grasslands are becoming shrublands/forests. In North America, eastern red cedar (Juniperus virginiana) often colonizes prairies. Habitat management can focus on woody removal, but we often lack long-term data on whether removal leads to population recovery of herbaceous plants without seeding. We undertook a long-term study (17 years) of numbers of the rare annual plant Agalinis auriculata in a gridwork of 100 m2 plots in adjacent prairie and oldfield sites in Kansas, USA. We collected data before and after removal of Juniperus virginiana at the prairie. Plant population sizes were highly variable at both sites and over time. High numbers of plants in a plot 1 year were often followed by low numbers the following year, suggesting negative density-dependence. Plant numbers were lowest with extensive woody cover and with low precipitation. After woody plant removal, A. auriculata increased dramatically in abundance and occupancy in most years; increases were also seen at the oldfield, suggesting later survey years were overall more favorable. Synthesis and applications: Removal of woody plants led to increased numbers of a rare annual prairie plant, without seeding. Multiple years of data were essential for interpretation given extreme temporal variability in numbers. The largest prairie population was 7 years following tree removal, showing that positive effects of management can last this long. This species also fared well in oldfield habitat, suggesting restoration opportunities. Given that land managers are busy, time-efficient field methods and data analysis approaches such as ours offer advantages. In addition to general linear models, we suggest Rank Occupancy-Abundance Profiles (ROAPs), a simple-to-use data visualization and analysis method. Creation of ROAPs for sites before and after habitat management helps reveal the degree to which plant populations are responding to management with changes in local density, changes in occupancy, or both.

Parenting in infancy and self-regulation in preschool: an investigation of the role of attachment history.

Parenting and attachment are critical in the emergence of self-regulation (SR) in preschool. However, most studies use general indexes of parenting quality, failing to explore the unique contributions of sensitivity and home quality to SR. Further, the nature of the interplay between parenting and attachment history is not well understood. Using a sample of 938 children from The National Institute of Child Health and Human Development Study of Early Child Care and Youth Development, a series of structural equation models were fit to determine whether sensitivity and home quality concurrently predicted SR at 54 months, and whether attachment mediated or moderated these pathways. Results suggest that both sensitivity and home quality uniquely predict SR. Further, these early parenting variables were each indirectly associated with SR through children's attachment history. That is, higher levels of sensitivity and home quality predicted secure attachment history, which, along with parenting, predicted more advanced SR skills at 54 months. No moderated pathways emerged, suggesting that attachment history may be best conceptualized as a mediating mechanism.

Sleep characteristics in Goldenhar Syndrome.

OBJECTIVE: To examine the characteristics of sleep in patients with Goldenhar Syndrome. DESIGN: Retrospective review of all polysomnography studies conducted at the University of North Carolina Hospitals between 2003 and 2013 on patients carrying the diagnosis of Goldenhar's Syndrome. RESULTS: A preponderance of patients demonstrated severe obstructive sleep apnea and hypercapnia. CONCLUSIONS: Patients with Goldenhar Syndrome should be screened for sleep apnea and hypercapnia.

The use of pharmacological prophylaxis against venous thromboembolism in hospitalised patients with severe active ulcerative colitis.

BACKGROUND: Hospitalised patients with inflammatory bowel disease are 1.5- to 3.5-fold more likely to develop venous thromboembolism compared to controls. Clinical guidelines recommend pharmacological prophylaxis. AIM: To determine the rate of pharmacological venous thromboembolism prophylaxis prescription and administration in a cohort of hospitalised patients with severe active ulcerative colitis and to assess predictors of failure to order pharmacological prophylaxis at 24 h. METHODS: This is a retrospective review of hospitalised patients with severe active ulcerative colitis, identified by ICD-9-CM discharge code 556.x, admitted to a single tertiary care hospital from 1 January 2005 to 31 August 2012. Adequate thromboembolism prophylaxis was defined as an order for low-dose unfractionated heparin two to three times daily, low-molecular weight heparin 40 mg daily or fondaparinux 2.5 mg daily ordered and administered for >80% of the admission. Patient related factors associated with failure to order prophylaxis at 24 h were accessed as secondary outcomes. RESULTS: Three hundred and thirty-six patients were hospitalised with severe active ulcerative colitis. Hospitalists had prescribed appropriate pharmacological prophylaxis by 48 h in only 37% of cases. Of these, nurses administered all prescribed doses in 18% of cases. Only 7% of patients (22/304, 95% CI: 5-11%) received adequate pharmacological prophylaxis for >80% of their hospitalisation. Hematochezia (P = 0.002), elevated platelets (P = 0.008), male gender coupled with younger age (P = 0.005) and admission on a biologic (P = 0.03) were associated with failure to order prophylaxis. CONCLUSION: Hospitalised patients admitted with severe active ulcerative colitis are not receiving appropriate pharmacological venous thromboembolism prophylaxis.

The effects of crude protein concentration and slow release urea on nitrogen metabolism in Holstein steers.

This experiment was conducted to determine the effects of slow release urea (SRU) and its interaction with crude protein (CP) level in the diet on N metabolism in Holstein steers. Eight rumen-cannulated Holstein steers (body weight 265 ± 18 kg) were used in a replicated 4 × 4 Latin square design with a 2 × 2 factorial treatment structure. Treatment factors were the CP level in the diet, 10.9% versus 12.1% CP, and the non-protein nitrogen source used, urea versus SRU. Total collection of urine and faeces for 7 days allowed the estimation of N retention and diet digestibility. In addition, blood and rumen sampling allowed estimation of rumen fermentation and blood N profiles. Decreasing CP intake from 12.1% to 10.9% reduced urinary N output, but also reduced diet digestibility and N retention. When compared to urea, SRU did not alter N retention, but reduced ruminal ammonia and plasma urea concentrations. Although SRU did not improve N retention at either CP level, rumen ammonia and plasma urea concentrations were reduced, which may indicate that SRU may carry a lower risk for toxicity when compared to urea when fed at higher dietary concentrations.

Heart period sensitivity to forced oscillations in ventilatory pressure.

Heart rate variability analysis is a dynamic method to estimate the autonomic control over the cardiac cycle. Although dysfunction in this control system may appear spontaneously, other deficits may require provocation of the system. In this article we describe a non-invasive method to perturb the autonomic influences on the cardiac cycle. We recorded the ECG and respiratory pressure of ten healthy volunteers while introducing a random forced oscillation pressure wave onto spontaneous respiration. The heart period time series was determined and the power spectra for the 0.05-0.15, 0.15-0.3 and 0.05-0.4 Hz bands were calculated. The random input did not alter mean heart rate. However, the segments with the forced oscillation input demonstrated, on average, a tenfold increase in spectral power averaged across all subjects, with a maximum observed effect of 100-fold increase in power. This increase in power correlated with the respiratory frequency. This study demonstrates that random noise ventilation, such as used in respiratory forced oscillation impedance estimates, significantly alters the autonomic input to cardiac cycle variability in wake subjects.

The impact of familial environment on depression scores after genetic testing for cancer susceptibility.

The associations between characteristics of family relationships and family trends in cancer worry and the psychological adjustment of recipients of genetic testing for cancer susceptibility were investigated. Data provided by 178 individuals from 24 families with Lynch syndrome who participated in a cohort study investigating psychological and behavioral outcomes of genetic testing were used. Responses from multiple family members were aggregated to construct family trends representing norms and departure from norms in cancer worry. Lower perceived family cohesion at baseline and decrease in this variable at 6 months after receipt of test results were associated with higher depression scores at 12 months. More variability in cancer worry among family members at baseline was also associated with higher depression scores at 12 months. Increase in family conflict was associated with decrease in depression scores among individuals from families with higher levels of cancer worry on average and less variability among the members. Family relationships and family trends in levels of cancer worry may play important roles in the psychological adjustment of genetic test recipients. The findings highlight the complexity of familial environment surrounding individuals that undergo genetic testing and suggest the benefits of considering these factors when providing genetic services.

Treating obstructive sleep apnea in adults with epilepsy: a randomized pilot trial.

OBJECTIVE: Small uncontrolled series suggest that treatment of obstructive sleep apnea (OSA) in patients with epilepsy may improve seizure control. Prior to conducting a definitive randomized controlled trial, we addressed critical design issues in a pilot study. METHODS: We identified a cohort of adult patients with medically refractory epilepsy and coexisting OSA, documented by polysomnography (PSG). After an 8-week baseline period, subjects with OSA were randomized to therapeutic or sham continuous positive airway pressure (CPAP) for 10 weeks. Subjects maintained seizure calendars and antiepileptic drug dosages were held constant. RESULTS: Sixty-eight subjects with suspected OSA were enrolled and 35 subjects randomized to therapeutic CPAP (22 subjects) or sham (13 subjects) CPAP. Male gender and an elevated sleep apnea questionnaire score were predictive of OSA on PSG. Nineteen subjects in the therapeutic group and all 13 subjects in the sham group completed the trial. Baseline apnea-hypopnea index (AHI) and CPAP adherence were comparable between groups. A significant reduction in AHI was observed in the therapeutic CPAP group as compared to the sham group. Subjects, study coordinators, and principal investigators were unable to predict treatment allocation. CONCLUSIONS: This pilot study provided critical information related to study design and feasibility for planning a comprehensive trial to test the hypothesis that treating obstructive sleep apnea in patients with epilepsy improves seizure control.

Production of recombinant adeno-associated type 5 (rAAV5) vectors using recombinant herpes simplex viruses containing rep and cap.

We developed a scaleable production system for adeno-associated virus type 5 (AAV5)-based vectors using a replication-defective recombinant herpes simplex type 1 virus (rHSV) containing the rep and cap genes of AAV5. Multiple rHSV isolates containing AAV5 rep and cap with normal or altered p5 promoter elements were constructed and tested in vector production. Compared with rAAV5 vector yields obtained by plasmid transfection, yields of rAAV5 using any of the rHSV isolates were low. Evidence suggests that the low vector yields are a consequence of the extensive and early cytopathology induced by the rHSV isolates. In addition, we found a correlation between the amount of Rep52 or Rep40 proteins and the amount of vector produced by each rHSV isolate, suggesting that packaging of vector DNA into virus particles is rate-limiting when using rHSV to generate rAAV5 vectors.

Dyadic analyses of friendship in a sample of preschool-age children attending Head Start: correspondence between measures and implications for social competence.

Friendships among a large sample of preschool-age children (N = 471) attending Head Start were assessed. Based on sociometric data, friendship dyads were identified as reciprocated (mutual choice) or nonreciprocated (unilateral choice). Dyads were further classified with respect to gender composition as either same- or mixed-gender dyads. Older children were more likely to participate in a reciprocated friendship than were younger children and reciprocated dyads were more likely to be same-gender than were nonreciprocated dyads. Analyses of interaction between dyad partners revealed that reciprocated friends interacted more frequently across all categories of interaction coded and looked at each other more frequently than did members of nonreciprocated dyads. For the positive interaction subscore, the friendship status effect was modified by a significant interaction with gender composition such that significant effects of friendship status were obtained only for same-gender dyads. Additional analyses indicated that the average social competence level was greater for reciprocated dyads than for nonreciprocated dyads. The findings suggest that reciprocated friendships are meaningful for preschool-age children and may serve as special socialization contexts in which the repertoire of behavior can be exercised and perhaps improved. They also highlight the salience of same-gender friendships in the preschool classroom.

Intraoperative methods for confirmation of correct placement of the vagus nerve stimulator.

Vagus nerve stimulation is a progressive therapy for intractable epilepsy. Variations in cervical anatomy can complicate localization of the vagus nerve and may lead to inappropriate placement of the stimulator leads. We have developed two intraoperative techniques that improve correct identification of the vagus nerve. Both of these techniques utilize the co-localization of the recurrent laryngeal nerve with the vagus nerve. For patients undergoing stimulator placement with regional and local anesthesia, the stimulator current intensity is increased until alteration of voice can be confirmed with a voice test. Patients undergoing general anesthesia can also be tested by direct stimulation of the isolated vagus nerve. Utilizing visualization of the larynx and vocal cords via fiberoptic endoscopy, direct stimulation of the vagus nerve will produce a contraction of the left lateral wall of the larynx and tightening of the left vocal cord. Neither of these procedures produce any untoward effects for the patients. We have found these methods improve our ability to confirm correct placement of the stimulator with minimal increase in operative time (with Video).

Periodic lateralized epileptiform discharges after complex partial status epilepticus associated with increased focal cerebral blood flow.

Periodic lateralized epileptiform discharges (PLEDs) are typically associated with encephalitis, cerebral abscess, cerebral infarct, and status epilepticus. There is considerable debate as to whether this pattern is ictal or interictal when seen in association with status epilepticus. We present a patient with complex partial status epilepticus who developed PLEDs and remained comatose despite optimal drug therapy. Technetium 99m single-photon emission computed tomography (SPECT) showed hyperperfusion that resolved with further aggressive antiepileptic drug therapy, indicating that this pattern may indeed be ictal. Further studies are needed to define the significance of PLEDs in patients with status epilepticus. The role of SPECT in differentiating PLEDs as an interictal or ictal pattern also requires further study.

Parasomnias--an update.

Primary parasomnias are a group of sleep-related clinical disorders that occur in otherwise healthy children, which may be provoked by a variety of physical, psychosocial, and environmental stimuli. In typical cases, additional investigations are not necessary, and treatment should be instituted with the aim of reducing the frequency and adverse consequences of the parasomnia. In patients with co-existing clinical disorders, parasomnias need to be distinguished from symptoms of the underlying disorder. This article provides a brief review of the recent literature regarding parasomnias, and a clinically oriented approach to the management of parasomnias in patients with co-existing clinical disorders.

Prospective long-term study of vagus nerve stimulation for the treatment of refractory seizures.

PURPOSE: To determine the long-term efficacy of vagus nerve stimulation (VNS) for refractory seizures. VNS is a new treatment for refractory epilepsy. Two short-term double-blind trials have demonstrated its safety and efficacy, and one long-term study in 114 patients has demonstrated a cumulative improvement in efficacy at 1 year. We report the largest prospective long-term study of VNS to date. METHODS: Patients with six or more complex partial or generalized tonic-clonic seizures enrolled in the pivotal EO5 study were prospectively evaluated for 12 months. The primary outcome variable was the percentage reduction in total seizure frequency at 3 and 12 months after completion of the acute EO5 trial, compared with the preimplantation baseline. Subjects originally randomized to low stimulation (active-control group) were crossed over to therapeutic stimulation settings for the first time. Subjects initially randomized to high settings were maintained on high settings throughout the 12-month study. RESULTS: The median reduction at 12 months after completion of the initial double-blind study was 45%. At 12 months, 35% of 195 subjects had a >50% reduction in seizures, and 20% of 195 had a >75% reduction in seizures. CONCLUSIONS: The efficacy of VNS improves during 12 months, and many subjects sustain >75% reductions in seizures.

Friendship and social competence in a sample of preschool children attending Head Start.

Relations between friendship (operationalized as reciprocated or nonreciprocated sociometric choices) and social competence were studied for children (mostly African American) attending Head Start. Initial analyses showed that children with reciprocated friends had higher social competence scores than children without reciprocated friends. Correlations suggested that the number of reciprocated friendships was associated with the social competence indicators studied here. Beyond the cost of having no reciprocated friends, having nonreciprocated friendships was not a liability. Cross-time analyses suggested differing patterns of relations for boys and girls. Having versus not having a reciprocated friend was unstable across time, because there was a trend toward participating in reciprocated friendships from 3 to 4 years of age (most older children had at least 1 reciprocated friend). For girls there was a positive relation between the number of reciprocated friendships at Time 1 and at Time 2. No benefit (in terms of social competence) was found for children making the transition from 1 classroom to the next with a friend.