Kilohertz quasiperiodic oscillations in short gamma-ray bursts.

Short gamma-ray bursts (GRBs) are associated with binary neutron star mergers, which are multimessenger astronomical events that have been observed both in gravitational waves and in the multiband electromagnetic spectrum1. Depending on the masses of the stars in the binary and on details of their largely unknown equation of state, a dynamically evolving and short-lived neutron star may be formed after the merger, existing for approximately 10-300 ms before collapsing to a black hole2,3. Numerical relativity simulations across different groups consistently show broad power spectral features in the 1-5-kHz range in the post-merger gravitational-wave signal4-14, which is inaccessible by current gravitational-wave detectors but could be seen by future third-generation ground-based detectors in the next decade15-17. This implies the possibility of quasiperiodic modulation of the emitted gamma rays in a subset of events in which a neutron star is formed shortly before the final collapse to a black hole18-21. Here we present two such signals identified in the short bursts GRB 910711 and GRB 931101B from archival Burst and Transient Source Experiment (BATSE) data, which are compatible with the predictions from numerical relativity.

The new frontier of gravitational waves.

In 2015, almost a century after Einstein published the general theory of relativity, one of its most important predictions was verified by direct detection: the production of gravitational waves in spacetime by accelerating objects. Since then, gravitational-wave astronomy has enabled tests of the nature of gravity and the properties of black holes, and in 2017 electromagnetic observations of a double neutron star merger producing gravitational waves led to a focus on multi-messenger astronomy. Here we review the history and accomplishments of gravitational-wave astronomy and look towards the future.

Prior differences in previous trauma exposure primarily drive the observed racial/ethnic differences in posttrauma depression and anxiety following a recent trauma.

BACKGROUND: Racial and ethnic groups in the USA differ in the prevalence of posttraumatic stress disorder (PTSD). Recent research however has not observed consistent racial/ethnic differences in posttraumatic stress in the early aftermath of trauma, suggesting that such differences in chronic PTSD rates may be related to differences in recovery over time. METHODS: As part of the multisite, longitudinal AURORA study, we investigated racial/ethnic differences in PTSD and related outcomes within 3 months after trauma. Participants (n = 930) were recruited from emergency departments across the USA and provided periodic (2 weeks, 8 weeks, and 3 months after trauma) self-report assessments of PTSD, depression, dissociation, anxiety, and resilience. Linear models were completed to investigate racial/ethnic differences in posttraumatic dysfunction with subsequent follow-up models assessing potential effects of prior life stressors. RESULTS: Racial/ethnic groups did not differ in symptoms over time; however, Black participants showed reduced posttraumatic depression and anxiety symptoms overall compared to Hispanic participants and White participants. Racial/ethnic differences were not attenuated after accounting for differences in sociodemographic factors. However, racial/ethnic differences in depression and anxiety were no longer significant after accounting for greater prior trauma exposure and childhood emotional abuse in White participants. CONCLUSIONS: The present findings suggest prior differences in previous trauma exposure partially mediate the observed racial/ethnic differences in posttraumatic depression and anxiety symptoms following a recent trauma. Our findings further demonstrate that racial/ethnic groups show similar rates of symptom recovery over time. Future work utilizing longer time-scale data is needed to elucidate potential racial/ethnic differences in long-term symptom trajectories.

Distinguishing spin-aligned and isotropic black hole populations with gravitational waves.

The direct detection of gravitational waves from merging binary black holes opens up a window into the environments in which binary black holes form. One signature of such environments is the angular distribution of the black hole spins. Binary systems that formed through dynamical interactions between already-compact objects are expected to have isotropic spin orientations (that is, the spins of the black holes are randomly oriented with respect to the orbit of the binary system), whereas those that formed from pairs of stars born together are more likely to have spins that are preferentially aligned with the orbit. The best-measured combination of spin parameters for each of the four likely binary black hole detections GW150914, LVT151012, GW151226 and GW170104 is the 'effective' spin. Here we report that, if the magnitudes of the black hole spins are allowed to extend to high values, the effective spins for these systems indicate a 0.015 odds ratio against an aligned angular distribution compared to an isotropic one. When considering the effect of ten additional detections, this odds ratio decreases to 2.9 × 10-7 against alignment. The existing preference for either an isotropic spin distribution or low spin magnitudes for the observed systems will be confirmed (or overturned) confidently in the near future.

Brain Tissue Oxygen and BOLD fMRI Under Different Levels of Neuronal Activity.

Localized increases in neuronal activity are supported by the hemodynamic response, which delivers oxygen to the brain tissue to support synaptic functions, action potentials and other neuronal processes. However, it remains unknown if changes in baseline neuronal activity, which are expected to reflect neuronal metabolic demand, alter the relationship between the local hemodynamic and oxygen behaviour. In order to better characterize this system, we examine here the relationship between brain tissue oxygen (PO2) and hemodynamic responses (BOLD functional MRI) under different levels of neuronal activity. By comparing the stimulus-evoked responses during different levels of baseline neuronal activity, the awake state vs isoflurane anesthesia, we were able to measure how a known change in neuronal demand affected tissue PO2 as well as the hemodynamic response to stimulation. We observed a high correlation between stimulus-evoked PO2 and BOLD responses in the awake state. Moreover, we found that the evoked PO2 and BOLD responses were still present despite the elevated tissue oxygen baseline and decreased baseline of neuronal activity under low concentration isoflurane, and that the magnitudes of these responses decreased by similar proportions but the relationship between these signals was distorted. Our findings point to distortion of the BOLD-PO2 relationship due to anesthesia. The feedback mechanism to adjust the level of brain tissue oxygen, as well as the correlation between BOLD and PO2 responses, are impaired even by a small dose of anesthetics.

HE4 and CA125 serum biomarker monitoring in women with epithelial ovarian cancer.

BACKGROUND: CA125 is the gold standard serum biomarker for monitoring patients with epithelial ovarian cancer (EOC). Human epididymal protein 4 (HE4) is a novel serum biomarker for EOC patients. OBJECTIVE: The objective of this trial was to examine the utility of measuring serum HE4 levels for monitoring EOC patients and to compare HE4 performance parameters to serum CA125. METHODS: A retrospective trial using residual longitudinal serum samples drawn during treatment and monitoring from EOC patients. Serum CA125 and HE4 levels were analyzed at each time point, and a velocity of change was calculated and correlated with clinical status. The null hypothesis was that HE4 is inferior to CA125, and this was tested using concordance and two-sided Fisher's exact testing. McNemar's test was used to assess the overall agreement of the two assays with the clinical status. RESULTS: A total of 129 patients with 272 separate clinical periods and 1739 events (serum samples) were evaluated. Using a 25% change in serum biomarker levels to indicate change in disease status, the accuracy and NPV determined for HE4 versus CA125 were 81.8% versus 82.6% (p = 0.846) and 87.4% versus 89.7% (p = 0.082), respectively. Concordance comparison of HE4 accuracy / CA125 accuracy was 0.990, indicating HE4 was not inferior to CA125 (McNemar's test p-value = 0.522). Performing a velocity of change analysis, the accuracy and NPV determined for HE4 versus CA125 were 78.3% versus 78.6% (p = 0.995) and 74.9% versus 76.3% (p = 0.815), respectively. Concordance comparison of HE4 velocity accuracy / CA125 velocity accuracy was 0.996, again indicating HE4 was not inferior to CA125 (McNemar's test p-value = 0.884). The combination of HE4 and CA125 velocity changes showed a similar accuracy of 81.3% (p = 0.797 compared to HE4 and CA125 alone) and NPV of 81.1% (p≥0.172 compared to HE4 and CA125 alone), and an increased sensitivity of 70.5% (p≤0.070 compared to HE4 and CA125 alone). CONCLUSION: HE4 is equivalent to CA125 for monitoring of EOC patients. The combination of CA125 and HE4 velocities is superior to either marker alone.

Potential health benefits of edible insects.

Animal-based foods have traditionally been viewed as dietary staples because they provide many essential nutrients; however, edible insects have the potential to serve as healthy, sustainable alternatives to these because of their nutrient contents. Edible insects may have superior health benefits due to their high levels of vitamin B12, iron, zinc, fiber, essential amino acids, omega-3 and omega-6 fatty acids, and antioxidants. The addition of edible insects such as crickets to the human diet could offer a myriad of environmental and nutritional benefits including an overall reduction in greenhouse gas emissions, decreased agricultural use of land and water, improved prevention and management of chronic diseases like diabetes, cancer, and cardiovascular disease, and enhanced immune function. Future research should aim to understand the beneficial effects of whole insects or insect isolates in comparison to traditional animal- and plant-based foodstuffs. Ultimately, insects have the potential to be used as meat substitutes or dietary supplements, resulting in human health and environmental benefits. The purpose of this review is to provide additional insight on the nutrient composition of edible insects, their potential use as meat substitutes or dietary supplements, the associated health and wellness benefits, and their potential role in exercise performance.

Super-response to guselkumab treatment in patients with moderate-to-severe psoriasis: age, body weight, baseline Psoriasis Area and Severity Index, and baseline Investigator's Global Assessment scores predict complete skin clearance.

BACKGROUND: Psoriasis is a chronic immune-mediated inflammatory skin disease that often leads to a diminished quality of life. Goals of treating patients with psoriasis have shifted with more focus on achieving near or complete clearance of the skin. Guselkumab, a fully human monoclonal antibody targeting interleukin-23, is effective in treating moderate-to-severe psoriasis. OBJECTIVE: To describe the baseline characteristics of patients with moderate-to-severe psoriasis achieving super-response (Psoriasis Area and Severity Index [PASI] 100 response at Weeks 20 and 28) after commencing guselkumab treatment. METHODS: Pooled data from VOYAGE 1 and VOYAGE 2 studies identified super-response; baseline demographic, disease and pharmacokinetic characteristics were compared with non-super-response. A stepwise logistic regression analysis identified which factors were potentially predictive of super-response status, with significance level of 0.1. RESULTS: A subset of patients randomized to guselkumab comprised this post hoc analysis (n = 664); 271 patients achieved super-response vs. 393 with non-super-response. Patient age at study entry and baseline body weight (≤90 kg vs. >90 kg), PASI, and Investigator's Global Assessment (IGA) score were significant predictors of super-response status, with odds ratios (95% confidence intervals) of 0.98 (0.967-0.993; P = 0.003), 1.42 (1.026-1.977; P = 0.034), 0.97 (0.955-0.993; P = 0.007) and 0.66 (0.433-0.997; P = 0.048), respectively. More patients with super-response achieved an early response: Week 2 PASI 75 (5.5% vs. 1.8%) and Week 8 PASI 100 (22.5% vs. 3.3%) vs. non-super-response. Median serum guselkumab concentrations through Week 28 were slightly greater in patients with super-response vs. non-super-response. CONCLUSION: Guselkumab was more likely to achieve early clinical responses (complete skin clearance) in younger patients, less obese patients and patients with less severe psoriasis.

Beverage behaviors and correlates among Head Start preschooler-parent dyads.

OBJECTIVES: To describe beverage behaviors among preschooler-parent dyads and explore correlates with preschooler's beverage behaviors. METHODS: This exploratory, cross-sectional study includes a convenience sample of 202 parents of preschoolers surveyed from four Head Start programs in Virginia and Ohio. Measurements included parent-child beverage behaviors, parent beverage perceptions, parent beverage rules, home beverage availability, and demographics. Analyses included descriptive statistics, correlations, Kruskal-Wallis test, and Quade's non-parametric ANCOVA tests. RESULTS: Mean sugar-sweetened beverage (SSB; i.e., regular soda, sweetened fruit drinks, sports/energy drinks, and coffee/tea with sugar) intake was 1.3 (SD = 1.4) and 2.3 (SD = 2.0) times/day for preschoolers and parents, respectively. When considering all sugary drink sources [i.e., summing SSB with flavored milk and 100% fruit juice (FJ)], the mean frequency increased to 3.2 (SD = 2.1) and 3.6 (SD = 2.4) times/day, respectively, for preschoolers and parents. A significant positive correlation was observed between preschooler-parent dyads for SSB (r = 0.406, p < 0.001) and for all sugary drinks (r = 0.572, p < 0.001). Parents who were younger, single, less educated, and with lower income had preschoolers with significantly higher SSB and all sugary drink intake (all p < 0.05). Significant correlates with preschoolers' beverage behaviors also included parent perceived behavioral control (SSB: p = 0.003, 100% FJ: p = 0.008, water: p < 0.0001), parenting practices (SSB: p = 0.022), and home availability (SSB: p = 0.011, 100% FJ: p < 0.001, water: p < 0.001). CONCLUSIONS: This study highlights excessive SSB and all sugary drink consumption among Head Start preschooler-parent dyads. Also, intervention targets to improve preschooler's beverage behaviors are identified, including efforts to improve parent's beverage behaviors, perceived behavioral control, parenting practices, and the home environment.

Electromagnetic counterparts to massive black-hole mergers.

The next two decades are expected to open the door to the first coincident detections of electromagnetic (EM) and gravitational-wave (GW) signatures associated with massive black-hole (MBH) binaries heading for coalescence. These detections will launch a new era of multimessenger astrophysics by expanding this growing field to the low-frequency GW regime and will provide an unprecedented understanding of the evolution of MBHs and galaxies. They will also constitute fundamentally new probes of cosmology and would enable unique tests of gravity. The aim of this Living Review is to provide an introduction to this research topic by presenting a summary of key findings, physical processes and ideas pertaining to EM counterparts to MBH mergers as they are known at the time of this writing. We review current observational evidence for close MBH binaries, discuss relevant physical processes and timescales, and summarize the possible EM counterparts to GWs in the precursor, coalescence, and afterglow stages of a MBH merger. We also describe open questions and discuss future prospects in this dynamic and quick-paced research area.

Alpelisib plus fulvestrant for PIK3CA-mutated, hormone receptor-positive, human epidermal growth factor receptor-2-negative advanced breast cancer: final overall survival results from SOLAR-1.

BACKGROUND: Activation of the phosphatidylinositol-3-kinase (PI3K) pathway via PIK3CA mutations occurs in 28%-46% of hormone receptor-positive (HR+), human epidermal growth factor receptor-2-negative (HER2-) advanced breast cancers (ABCs) and is associated with poor prognosis. The SOLAR-1 trial showed that the addition of alpelisib to fulvestrant treatment provided statistically significant and clinically meaningful progression-free survival (PFS) benefit in PIK3CA-mutated, HR+, HER2- ABC. PATIENTS AND METHODS: Men and postmenopausal women with HR+, HER2- ABC whose disease progressed on or after aromatase inhibitor (AI) were randomized 1 : 1 to receive alpelisib (300 mg/day) plus fulvestrant (500 mg every 28 days and once on day 15) or placebo plus fulvestrant. Overall survival (OS) in the PIK3CA-mutant cohort was evaluated by Kaplan-Meier methodology and a one-sided stratified log-rank test was carried out with an O'Brien-Fleming efficacy boundary of P ≤ 0.0161. RESULTS: In the PIK3CA-mutated cohort (n = 341), median OS [95% confidence interval (CI)] was 39.3 months (34.1-44.9) for alpelisib-fulvestrant and 31.4 months (26.8-41.3) for placebo-fulvestrant [hazard ratio (HR) = 0.86 (95% CI, 0.64-1.15; P = 0.15)]. OS results did not cross the prespecified efficacy boundary. Median OS (95% CI) in patients with lung and/or liver metastases was 37.2 months (28.7-43.6) and 22.8 months (19.0-26.8) in the alpelisib-fulvestrant and placebo-fulvestrant arms, respectively [HR = 0.68 (0.46-1.00)]. Median times to chemotherapy (95% CI) for the alpelisib-fulvestrant and placebo-fulvestrant arms were 23.3 months (15.2-28.4) and 14.8 months (10.5-22.6), respectively [HR = 0.72 (0.54-0.95)]. No new safety signals were observed with longer follow-up. CONCLUSIONS: Although the analysis did not cross the prespecified boundary for statistical significance, there was a 7.9-month numeric improvement in median OS when alpelisib was added to fulvestrant treatment of patients with PIK3CA-mutated, HR+, HER2- ABC. Overall, these results further support the statistically significant prolongation of PFS observed with alpelisib plus fulvestrant in this population, which has a poor prognosis due to a PIK3CA mutation. CLINICALTRIALS. GOV ID: NCT02437318.

Analysis of serum HE4 levels in various histologic subtypes of epithelial ovarian cancer and other malignant tumors.

BACKGROUND: The measurement of serum HE4 levels has emerged as a sensitive and specific biomarker for epithelial ovarian cancers (EOCs). However, serum levels in women diagnosed with various histologic subtypes of EOC and in women with metastatic non-ovarian primary malignancies have not been widely reported. OBJECTIVE: The goal of this study was to identify how serum HE4 levels vary in women diagnosed with different histologic subtypes of EOC and non-ovarian malignancies. METHODS: Data from six prospective pelvic mass clinical trials was combined and an evaluation of serum HE4 levels in women diagnosed with a malignancy was performed. For all patients, serum was obtained prior to surgery and final pathology, including primary tumor site, histologic subtype, grade and stage, were recorded. The mean, median, standard deviation, maximum, and minimum HE4 levels were determined for each group. RESULTS: A total of 984 patients were included in this study, with the average patient age being 60 years old. There were 230 premenopausal and 754 postmenopausal patients. Serum HE4 levels were elevated (≥70.0 pMol) in 85%of EOCs, 40%of LMP tumors, 21%of non-EOCs (germ cell tumors), 25%of cervical cancers, and 47%of non-gynecologic metastatic cancers. Analysis of histologic subtypes revealed 90%(n = 391) of serous, 85%(n = 73) of endometrioid, 45%(n = 42) of mucinous, 86%(n = 51) of mixed tumors, and 69%(n = 36) of clear cell tumors had elevated serum HE4 levels. CONCLUSIONS: Serum HE4 levels are most often elevated in women with high grade serous and endometrioid EOCs, and though serum elevations are seen more often with advanced stage disease, HE4 is also often elevated in early stage disease and lower grade tumors.

Five-year maintenance of clinical response and health-related quality of life improvements in patients with moderate-to-severe psoriasis treated with guselkumab: results from VOYAGE 1 and VOYAGE 2.

BACKGROUND: Psoriasis is a chronic disease requiring long-term therapy. OBJECTIVES: Physician- and patient-reported outcomes were evaluated through week 252 in VOYAGE 1 and VOYAGE 2. METHODS: In total, 1829 patients were randomized at baseline to receive guselkumab 100 mg every 8 weeks, placebo or adalimumab. Patients receiving placebo crossed over to guselkumab at week 16. Patients receiving adalimumab crossed over to guselkumab at week 52 in VOYAGE 1, and randomized withdrawal and retreatment occurred at weeks 28-76 in VOYAGE 2; all patients then received open-label guselkumab through week 252. Efficacy and health-related quality of life (HRQoL) endpoints were analysed through week 252. Safety was monitored through week 264. RESULTS: The proportions of patients in the guselkumab group who achieved clinical responses at week 252 in VOYAGE 1 and VOYAGE 2, respectively, were 84·1% and 82·0% [≥ 90% improvement in Psoriasis Area and Severity Index (PASI)]; 82·4% and 85·0% [Investigator's Global Assessment (IGA) 0 or 1]; 52·7% and 53·0% (100% improvement in PASI) and 54·7% and 55·5% (IGA 0). HRQoL endpoints were achieved as follows: 72·7% and 71·1% of patients (Dermatology Life Quality Index 0 or 1: no effect on patient's life); 42·4% and 42·0% [Psoriasis Symptoms and Signs Diary (PSSD) symptom score = 0] and 33·0% and 31·0% (PSSD sign score = 0). As measured in VOYAGE 2 only, approximately 45% of patients achieved ≥ 5-point reduction in Short Form-36 physical and mental component scores, and 80% reported no anxiety or depression (Hospital Anxiety and Depression Scale scores < 8). Similar findings were reported for adalimumab crossovers. These effects were maintained from week 52 in VOYAGE 1 and week 100 in VOYAGE 2. No new safety signals were identified. CONCLUSIONS: Guselkumab maintains high levels of clinical response and improvement in patient-reported outcomes through 5 years in patients with moderate-to-severe psoriasis.

Flows of X-ray gas reveal the disruption of a star by a massive black hole.

Tidal forces close to massive black holes can violently disrupt stars that make a close approach. These extreme events are discovered via bright X-ray and optical/ultraviolet flares in galactic centres. Prior studies based on modelling decaying flux trends have been able to estimate broad properties, such as the mass accretion rate. Here we report the detection of flows of hot, ionized gas in high-resolution X-ray spectra of a nearby tidal disruption event, ASASSN-14li in the galaxy PGC 043234. Variability within the absorption-dominated spectra indicates that the gas is relatively close to the black hole. Narrow linewidths indicate that the gas does not stretch over a large range of radii, giving a low volume filling factor. Modest outflow speeds of a few hundred kilometres per second are observed; these are below the escape speed from the radius set by variability. The gas flow is consistent with a rotating wind from the inner, super-Eddington region of a nascent accretion disk, or with a filament of disrupted stellar gas near to the apocentre of an elliptical orbit. Flows of this sort are predicted by fundamental analytical theory and more recent numerical simulations.

'It's changed how we have these conversations': emergency department clinicians' experiences implementing firearms and other lethal suicide methods counseling for caregivers of adolescents.

Counseling parents to reduce access to firearms and other potentially lethal suicide methods is commonly known as lethal means counseling (LMC). The current study explores the experiences that emergency department-based behavioural health clinicians described having as they provided lethal means counseling to parents of adolescents at risk for suicide. Clinicians were purposively sampled from four hospital networks in Colorado after their hospitals adopted LMC protocols as part of an intervention that also included online training in LMC and provision of free medication and firearm lockboxes. Twenty-three clinicians were interviewed using semi-structured interviews. Data were analysed using a modified grounded theory-based approach. Clinicians felt more comfortable and effective in their abilities to provide LMC after the intervention. Clinicians also described how being able to offer free storage devices helped them engage in LMC. In advising parents to make guns and medications inaccessible to their at-risk child, most clinicians pointed to at least one of three research findings highlighted in the online training: (1) Suicide attempts with guns rarely afford second chances, (2) medication overdoses can kill, (3) suicidal behaviour is always unpredictable and often impulsive. All clinicians described a desire to continue LMC as currently protocolized at their hospital after the study ended.

A retrospective single-site data-linkage study comparing manual to electronic data abstraction for routine post-operative nausea and vomiting audit.

BACKGROUND: Post-operative nausea and vomiting (PONV) is a common cause of patient dissatisfaction following anaesthesia. Audit of adherence to PONV prevention guidelines is resource intensive when performed by manual chart extraction. Electronic audit can require costly anaesthetic and medical records. OBJECTIVE: In our single-site study we sought to compare manual and electronic PONV audits by utilizing existing non-anaesthetic electronic medical records to avoid expensive additional software. METHODS: The audits were performed from 13 January 2020 to 1 February 2020 for surgical inpatients. Two PONV periods were captured-the post-anaesthetic recovery unit and on the ward (to 24 h). Electronic PONV was defined as the administration of an anti-emetic medication. A 6-month electronic PONV rate was also calculated. RESULTS: Manual audit captured 142 patients and electronic audit captured 294 patients, over the same time period. The manual PONV rate was 10% (95% confidence interval (CI) 5-16%) in the post-anaesthetic recovery unit and 20% (95% CI 14-28%) the next day. The electronic rate was 5% (95% CI 3-8%) in the post-anaesthetic recovery unit and 15% (11-19%) in a 24-h period. The 6-month electronic audit found 3510 patients, with a post-anaesthetic recovery unit and 24-h PONV rates of 5% (4-6%) and 14% (13-16%), respectively. Electronic audit did not identify 5.8% of PONV patients in the manual audit. CONCLUSION: Electronic audit enrolled more patients and identified a lower PONV rate than manual audit, likely from less enrolment bias. Electronic audit was easily repeated over a 6-month period. While electronic PONV audit is possible without additional software, an electronic anaesthetic chart would greatly improve audit quality.

Evaluating the effects of Lactobacillus animalis and Propionibacterium freudenreichii on performance and rumen and fecal measures in lactating dairy cows.

Two experiments evaluated the effect of supplementation with a bacterial direct-fed microbial on performance and apparent total-tract nutrient digestion of dairy cows. In experiment 1, 30 multiparous cows (75 ± 32 d in milk) were randomly assigned to 1 of 2 treatments fed for 10 wk. All cows were fed a diet containing 23.8% starch. Treatments were top dressed to rations twice daily and consisted of a combination of Lactobacillus animalis (1 × 109 cfu/d) and Propionibacterium freudenreichii (2 × 109 cfu/d; LAPF) or carrier alone (CON). In experiment 2, 6 ruminally cannulated cows (123 ± 129 d in milk) were randomly assigned to a crossover design with two 6-wk periods. Cows received the same CON or LAPF treatment as in experiment 1. Cows were fed the same 23.8% starch diet as experiment 1 during wk 1 through 5 of each period, and then cows were abruptly switched to a 31.1% starch diet for wk 6. For both experiments, intake and milk yield were measured daily, and milk samples were collected weekly. In experiment 1, fecal grab samples were collected every 6 h on d 7 of experimental wk 1, 2, 4, 6, 8, and 10. Fecal consistency was scored, and fecal starch was measured in daily composite samples. Fecal composites from a subset of 7 cows per treatment were used to measure apparent total-tract nutrient digestion. In experiment 2, rumen pH was continuously recorded during wk 5 and 6. On d 7 of wk 5 (the final day of feeding the 23.8% starch ration), d 1 of wk 6 (the day of diet transition), and d 7 of wk 6 (the final day of feeding the 31.1% starch ration), rumen in situ digestion was determined. Samples of rumen fluid and feces were collected every 6 h on those days for measurement of fecal starch (composited by cow within day), rumen volatile fatty acids, and fecal pH. Rumen and fecal samples were collected at one time point on those days for microbiota assessment. In experiment 1, treatment did not affect intake, milk yield, milk composition, or fecal score. The LAPF treatment decreased fecal starch percentage and tended to increase starch digestion compared with CON, but the differences were very small (0.59 vs. 0.78% and 98.74 vs. 98.46%, respectively). Digestion of other nutrients was unaffected. In experiment 2, LAPF increased rumen pH following the abrupt switch to the high-starch diet, but milk yield was lower for LAPF compared with CON (35.7 vs. 33.2 kg/d). Contrary to the decrease in fecal starch with LAPF observed in experiment 1, fecal starch tended to be increased by LAPF following the abrupt ration change in experiment 2 (2.97 vs. 2.15%). Few effects of treatment on rumen and fecal microbial populations were detectable. Under the conditions used in our experiments, addition of the bacterial direct-fed microbials did not have a marked effect on animal performance, ruminal measures, or total-tract nutrient digestion.

The effects of air stress during storage and low packing density on the fermentation and aerobic stability of corn silage inoculated with Lactobacillus buchneri 40788.

We determined if a microbial inoculant could improve the fermentation and aerobic stability of corn silage subjected to various challenges during storage that included an air stress challenge and low packing density. In Experiment 1, whole-plant corn was untreated (CTR) or treated (INO, Lactobacillus buchneri 40788 and Pediococcus pentosaceus 12455. Five individually replicated 7.5-L silos, at a density of 240 kg of dry matter (DM)/m3, for each treatment were kept sealed (NAS) for 19 wk, air stressed early (ES, 3 h/wk for wk 1-9), or air stressed late during storage (LS, 3 h/wk for wk 10-19). Inoculation increased the number of agar-culturable lactic acid bacteria regardless of air stress status, but it did not affect the relative abundance of Lactobacillus. Early, but not late air stress, resulted in silages with a higher relative abundance of Acetobacter when compared with NAS. Silages treated with INO had greater concentrations of acetic acid than CTR. Numbers of yeasts were lowest for INO regardless of air stress and CTR-LS had the most yeasts among all treatments. Silages that were not air stressed had a higher relative abundance of Candida tropicalis than air stressed silages. Monascus purpureus was detected in ES and LS but not in NAS, and its relative abundance was numerically higher in CTR-ES than in INO-ES and statistically higher in CTR-LS compared with INO-LS. Early air stress numerically reduced aerobic stability compared with NAS, and there was a statistical tendency for lower stability in LS compared with NAS. Inoculation improved aerobic stability regardless of when the air stress occurred. In Experiment 2, corn silage was prepared with the same primary treatments of CTR and INO but was packed at a low (LD; 180 kg of DM/m3) or a normal (ND; 240 kg of DM/m3) density and sealed (NAS) or air stressed (AS; 24 h on d 28, 42, and 89) for 92 d of storage. The concentration of acetic acid was greater in INO compared with CTR and in AS compared with NAS. Numbers of yeasts were lower in NAS compared with AS regardless of inoculation and they were lower in INO-AS compared with CTR-AS. Treatment with INO improved aerobic stability but the improvement was better in NAS versus AS and better in ND versus LD. Overall, our experiments corroborate past findings showing that INO markedly improves the aerobic stability of corn silage but they are the first to show that improvement can be sustained even when the silage was exposed to regular air stresses and when packed at a low density.

Influence of fiber degradability of corn silage in diets with lower and higher fiber content on lactational performance, nutrient digestibility, and ruminal characteristics in lactating Holstein cows.

The effect of neutral detergent fiber (NDF) degradability of corn silage in diets containing lower and higher NDF concentrations on lactational performance, nutrient digestibility, and ruminal characteristics in lactating Holstein cows was measured. Eight ruminally cannulated Holstein cows averaging 91 ± 4 (standard error) days in milk were used in a replicated 4 × 4 Latin square design with 21-d periods (7-d collection periods). Dietary treatments were formulated to contain either conventional (CON; 48.6% 24-h NDF degradability; NDFD) or brown midrib-3 (BM3; 61.1% 24-h NDFD) corn silage and either lower NDF (LNDF) or higher NDF (HNDF) concentration (32.0 and 35.8% of ration dry matter, DM) by adjusting the dietary forage content (52 and 67% forage, DM basis). The dietary treatments were (1) CON-LNDF, (2) CON-HNDF, (3) BM3-LNDF, and (4) BM3-HNDF. Data were analyzed as a factorial arrangement of diets within a replicated Latin square design with the MIXED procedure of SAS (SAS Institute Inc., Cary, NC) with fixed effects of NDFD, NDF, NDFD × NDF, period(square), and square. Cow within square was the random effect. Time and its interactions with NDFD and NDF were included in the model when appropriate. An interaction between NDFD and NDF content resulted in the HNDF diet decreasing dry matter intake (DMI) with CON corn silage but not with BM3 silage. Cows fed the BM3 corn silage had higher DMI than cows fed the CON corn silage, whereas cows fed the HNDF diet consumed less DM than cows fed the LNDF diet. Cows fed the BM3 diets had greater energy-corrected milk yield, higher milk true protein content, and lower milk urea nitrogen concentration than cows fed CON diets. Additionally, cows fed the BM3 diets had greater total-tract digestibility of organic matter and NDF than cows fed the CON diets. Compared with CON diets, the BMR diets accelerated ruminal NDF turnover. When incorporated into higher NDF diets, corn silage with greater in vitro 24-h NDFD and lower undegradable NDF at 240 h of in vitro fermentation (uNDF240) allowed for greater DMI intake than CON. In contrast, for lower NDF diets, NDFD of corn silage did not affect DMI, which suggests that a threshold level of inclusion of higher NDFD corn silage is necessary to observe enhanced lactational performance. Results suggest that there is a maximum gut fill of dietary uNDF240 and that higher NDFD corn silage can be fed at greater dietary concentrations.

Polyaromatic hydrocarbons in pollution: a heart-breaking matter.

Air pollution is associated with detrimental effects on human health, including decreased cardiovascular function. However, the causative mechanisms behind these effects have yet to be fully elucidated. Here we review the current epidemiological, clinical and experimental evidence linking pollution with cardiovascular dysfunction. Our focus is on particulate matter (PM) and the associated low molecular weight polycyclic aromatic hydrocarbons (PAHs) as key mediators of cardiotoxicity. We begin by reviewing the growing epidemiological evidence linking air pollution to cardiovascular dysfunction in humans. We next address the pollution-based cardiotoxic mechanisms first identified in fish following the release of large quantities of PAHs into the marine environment from point oil spills (e.g. Deepwater Horizon). We finish by discussing the current state of mechanistic knowledge linking PM and PAH exposure to mammalian cardiovascular patho-physiologies such as atherosclerosis, cardiac hypertrophy, arrhythmias, contractile dysfunction and the underlying alterations in gene regulation. Our aim is to show conservation of toxicant pathways and cellular targets across vertebrate hearts to allow a broad framework of the global problem of cardiotoxic pollution to be established. AhR; Aryl hydrocarbon receptor. Dark lines indicate topics discussed in this review. Grey lines indicate topics reviewed elsewhere.