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In recent years, it has become apparent that human impacts have altered community structure in coastal and marine ecosystems worldwide. Of these, fishing is one of the most pervasive, and a growing body of work suggests that fishing can have strong effects on the ecology of target species, especially top predators. However, the effects of removing top predators on lower trophic groups of prey fishes are less clear, particularly in highly diverse and trophically complex coral reef ecosystems. We examined patterns of abundance, size structure, and age-based demography through surveys and collection-based studies of five fish species from a variety of trophic levels at Kiritimati and Palmyra, two nearby atolls in the Northern Line Islands. These islands have similar biogeography and oceanography, and yet Kiritimati has ,10,000 people with extensive local fishing while Palmyra is a US National Wildlife Refuge with no permanent human population, no fishing, and an intact predator fauna. Surveys indicated that top predators were relatively larger and more abundant at unfished Palmyra, while prey functional groups were relatively smaller but showed no clear trends in abundance as would be expected from classic trophic cascades. Through detailed analyses of focal species, we found that size and longevity of a top predator were lower at fished Kiritimati than at unfished Palmyra. Demographic patterns also shifted dramatically for 4 of 5 fish species in lower trophic groups, opposite in direction to the top predator, including decreases in average size and longevity at Palmyra relative to Kiritimati. Overall, these results suggest that fishing may alter community structure in complex and non-intuitive ways, and that indirect demographic effects should be considered more broadly in ecosystembased management. [ABSTRACT FROM AUTHOR]

One of the most compelling unanswered questions in marine ecology is the extent to which local populations are connected via larval exchange. Recent work has suggested that variation in the chemistry of otoliths (earstones) of fishes may function as a natural tag, potentially allowing investigators to determine sources of individual larvae and estimate larval connectivity. We analyzed the spatial and temporal variation in natal otolith chemistry of a benthic-spawning reef fish from the Hawaiian Islands. We found no consistent chemical variation at the largest scale (>100 km, among islands), but found significant variation at moderate scales (sites within islands, tens of kilometres) and small scales (clutches within sites), and chemistry of otoliths was not stable between years. These results imply that we may be able to use otolith chemistry to track larval dispersal only if the scales of dispersal match those of variation in natal otolith chemistry, and that separate natal otolith collections may be needed to track different cohorts of larvae. Finally, we found that elemental composition of recruit cores often did not match that of natal otoliths, suggesting that additional methodological development is required before we can effectively apply methods in otolith chemistry to the study of larval dispersal. [ABSTRACT FROM AUTHOR]

Focuses on the approaches being used by the U.S. National Aeronautics and Space Administration (NASA) to create reliable software for its space exploration missions. Mission control and planning; Autonomous systems; Software quality initiative; Software reliability research; Design of next-generation systems; Dynamics of static analysis.

Reports on the development of technologies by the U.S.-based computer company, Intel Corp. to aid in proactive computing and research. Development of a research network model; Expertise in microachitecture and circuit design; Details about several research by the company. INSET: Corporate Technology Group..

Presents the results of a United States Food and Drug Administration-mandated study called 'Standard Treatment with Alteplase to Reverse Stroke' (STARS). Tissue-type plasminogen activator and its use in treating acute ischemic stroke; Context; Objective; Design and Setting; Intervention; Patients; Main outcome measures; Results; Conclusions.

Focuses on the research of the United States National Aeronautics and Space Administration (NASA) Ames Research Center into artificial intelligence (AI) and high performance computing. Information on the Remote Agent AI software; Reasons for the investment in AI research; Characteristics of the artificial neural networks (ANN). INSETS: FutureFlight Central;NASA Center of Excellence for Information Technology.

Presents an overview of electronic commerce ventures in the United States. Vision of CommerceNet Consortium; Virtual stores for business-to-business relationships; Need for interoperability between applications.

Assesses the implications of alternative response assumptions on the estimates of changes in welfare, prices and production due to environmental alterations in the United States. Theoretical refinement of aggregate response assumptions; Implementation of flexibility constraints in crop modification; Mathematical evaluation on the consequences of assumptions.

Based upon early ethnographic accounts, the ice-glider was a recreational artifact, with limited distribution in time and space, first appearing in the early historic period and confined to the Missouri River drainage. Recent research has shown a more broad distribution across both time and space, extending its use into the precontact period and extending its distribution northward into the Northern Plains and the adjacent Parklands of Canada. Its earliest dated occurrence is in the parklands of southern Manitoba and the southern plains of Saskatchewan circa 1440 A.D. Ice-gliders provide a glimpse of non-subsistence activities of First Nations people prior to the advent of Europeans in the region. They also provide a useful indicator of site seasonality. Elaborate decoration on some specimens suggests to the authors that the ice-glider may have had non-secular applications as well. [ABSTRACT FROM AUTHOR]

Background: Long-term disability after stroke is standardly assessed 3 months post-onset, using the modified Rankin Scale (mRS). The value of an early, day 4 mRS assessment for projecting the 3-month disability outcome has not been formally investigated., Methods: In this cohort of patients with acute cerebral ischemia and intracranial hemorrhage, we analyzed day 4 and day 90 mRS assessments in the NIH Field Administration of Stroke Therapy- Magnesium (FAST-MAG) Phase 3 trial. The performance of day 4 mRS, alone and as part of multivariate models, in predicting day 90 mRS was assessed using correlation coefficients, percent agreement, and the kappa statistics., Results: Among the 1573 acute cerebrovascular disease (ACVD) patients, 1206 (76.7%) had acute cerebral ischemia (ACI), while 367 (23.3%) had intracranial hemorrhage. Among all 1573 ACVD patients, day 4 mRS and day 90 mRS correlated strongly, Spearman's rho=0.79, in unadjusted analysis with weighted kappa of 0.59. For dichotomized outcomes, simple carry-forward of the day 4 mRS performed fairly well in agreeing with day 90 mRS: mRS 0-1 (kappa=0.67), 85.4%; mRS 0-2 (k=0.59), 79.5%; fatal outcome, 88% (k=0.33). Correlations of 4d and 90d mRS were stronger for ACI than ICH patients, 0.76 vs 0.71., Conclusions: In this acute cerebrovascular disease patient cohort, assessment of global disability performed on day 4 is highly informative regarding long-term, 3-month mRS disability outcome, alone, and even more strongly in combination with baseline prognostic variables. The day 4 mRS is a useful measure for imputing the final patient disability outcome in clinical trials and quality improvement programs., Competing Interests: Declaration of competing interest JLS, ST, JL, SS, SH, RC, NS, SA, JG have no competing interests as defined by Journal of Stroke and Cerebrovascular Diseases. Other interests that might be perceived to influence the results and/or discussion reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Background: Blood pressure variability (BPV) has emerged as a significant factor associated with clinical outcomes after intracerebral hemorrhage (ICH). Although hematoma expansion (HE) is associated with clinical outcomes, the relationship between BPV that encompasses prehospital data and HE is unknown. We hypothesized that BPV was positively associated with HE., Methods: We analyzed 268 patients with primary ICH enrolled in the National Institutes of Health-funded Field Administration of Stroke Therapy-Magnesium (FAST-MAG) study who received head computed tomography or magnetic resonance imaging on arrival to the emergency department (ED) and repeat imaging within 6-48 h. BPV was calculated by standard deviation (SD) and coefficient of variation (CV) from prehospital data as well as systolic blood pressure (SBP) measurements taken on ED arrival, 15 min post antihypertensive infusion start, 1 h post maintenance infusion start, and 4 h after ED arrival. HE was defined by hematoma volume expansion increase > 6 mL or by 33%. Univariate logistic regression was used for presence of HE in quintiles of SD and CV of SBP for demographics and clinical characteristics., Results: Of the 268 patients analyzed from the FAST-MAG study, 116 (43%) had HE. Proportions of patients with HE were not statistically significant in the higher quintiles of the SD and CV of SBP for either the hyperacute or the acute period. Presence of HE was significantly more common in patients on anticoagulation., Conclusions: Higher BPV was not found to be associated with occurrence of HE in the hyperacute or the acute period of spontaneous ICH. Further study is needed to determine the relationship., (© 2022. Springer Science+Business Media, LLC, part of Springer Nature and Neurocritical Care Society.)

Background: Intracerebral hemorrhage (ICH) is the deadliest form of stroke. In observational studies, lower serum magnesium has been linked to more hematoma expansion (HE) and intracranial hemorrhage, implying that supplemental magnesium sulfate is a potential acute treatment for patients with ICH and could reduce HE. FAST-MAG (Field Administration of Stroke Therapy - Magnesium) was a clinical trial of magnesium sulfate started prehospital in patients with acute stroke within 2 hours of last known well enrolled. CT was not required prior to enrollment, and several hundred patients with acute ICH were enrolled. In this ancillary analysis, we assessed the effect of magnesium sulfate treatment upon HE in patients with acute ICH., Methods: We retrospectively analyzed data that were prospectively collected in the FAST-MAG study. Patients received intravenous magnesium sulfate or matched placebo within 2 hours of onset. We compared HE among patients allocated to intravenous magnesium sulfate or placebo with a Mann-Whitney U . We used the same method to compare neurological deficit severity (National Institutes of Health Stroke Scale) and global disability (modified Rankin Scale) at 3 months., Results: Among 268 patients with ICH meeting study entry criteria, mean 65.4±13/4 years, 33% were female, and 211 (79%) had a history of hypertension. Initial deficit severities were median (interquartile range) of 4 (3-5) on the Los Angeles Motor Scale in the field and National Institutes of Health Stroke Scale score of 16 (9.5-25.5) early after hospital arrival. Follow-up brain imaging was performed a median of 17.1 (11.3-22.7) hours after first scan. The magnesium and placebo groups did not statistically differ in hematoma volume on arrival, 10.1 (5.6-28.7) versus 12.4 (5.6-28.7) mL ( P =0.6), or HE, 2.0 (0.1-7.4) versus 1.5 (-0.2 to 8) mL ( P =0.5). There was no difference in functional outcomes (modified Rankin Scale score of 3-6), 59% versus 50% ( P =0.5)., Conclusions: Magnesium sulfate did not reduce HE or improve functional outcomes at 90 days. A benefit for patients with initial hypomagnesemia was not addressed., Registration: URL: https://www., Clinicaltrials: gov; Unique identifier: NCT00059332.

Objectives: The US Centers for Medicare and Medicaid Services (CMS) currently publicly reports hospital-quality, risk-adjusted mortality measure for ischemic stroke but not intracerebral hemorrhage (ICH). The NIHSS, which is captured in CMS administrative claims data, is a candidate metric for use in ICH risk adjustment and has been shown to predict clinical outcome with accuracy similar to the ICH Score. Correlation between early NIHSS and initial ICH volume would further support use of the NIHSS for ICH risk adjustment., Materials and Methods: Among 372 ICH patients enrolled in a large multicenter trial (FAST-MAG), the relation between early NIHSS and early ICH volume was assessed with correlation and linear trend analysis., Results: Overall, there was strong correlation between NIHSS and ICH volume, r = 0.77 (p < 0.001), and for every 10cc increase in ICH the NIHSS increased by 4.5 points. Correlation coefficients were comparable in all subgroups, but magnitude of NIHSS increase with ICH unit volume increase was greater with left than right hemispheric ICH, with presence rather than absence of IVH, with imaging done within the first hour than second hour after last known well, with men than women, and with younger than older patients., Conclusion: Early NIHSS neurologic deficit severity values correlate strongly with initial ICH hematoma volume. As with ischemic stroke, lesion volume increases produce greater NIHSS change in the left than right hemisphere, reflecting greater NIHSS sensitivity to left hemisphere function. These findings provide further support for the use of NIHSS in risk-adjusted mortality measures for intracerebral hemorrhage., Competing Interests: Declaration of Competing Interest None, (Copyright © 2022. Published by Elsevier Inc.)

The unusual blue color polymorphism of lingcod (Ophiodon elongatus) is the subject of much speculation but little empirical research; ~20% of lingcod individuals exhibit this striking blue color morph, which is discrete from and found within the same populations as the more common brown morph. In other species, color polymorphisms are intimately linked with host-parasite interactions, which led us to ask whether blue coloration in lingcod might be associated with parasitism, either as cause or effect. To test how color and parasitism are related in this host species, we performed parasitological dissection of 89 lingcod individuals collected across more than 26 degrees of latitude from Alaska, Washington, and California, USA. We found that male lingcod carried 1.89 times more parasites if they were blue than if they were brown, whereas there was no difference in parasite burden between blue and brown female lingcod. Blue individuals of both sexes had lower hepatosomatic index (i.e., relative liver weight) values than did brown individuals, indicating that blueness is associated with poor body condition. The immune systems of male vertebrates are typically less effective than those of females, due to the immunocompromising properties of male sex hormones; this might explain why blueness is associated with elevated parasite burdens in males but not in females. What remains to be determined is whether parasites induce physiological damage that produces blueness or if both blue coloration and parasite burden are driven by some unmeasured variable, such as starvation. Although our study cannot discriminate between these possibilities, our data suggest that the immune system could be involved in the blue color polymorphism-an exciting jumping-off point for future research to definitively identify the cause of lingcod blueness and a hint that immunocompetence and parasitism may play a role in lingcod population dynamics., Competing Interests: The authors have declared that no competing interests exist.

Background and Purpose- DAWN (Clinical Mismatch in the Triage of Wake Up and Late Presenting Strokes Undergoing Neurointervention With Trevo) and DEFUSE 3 (Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke) established thrombectomy for patients with emergent large vessel occlusions presenting 6 to 24 hours after symptom onset. Given the greater inclusivity of DEFUSE 3, we evaluated the effect of thrombectomy in DEFUSE 3 patients who would have been excluded from DAWN. Methods- Eligibility criteria of the DAWN trial were applied to DEFUSE 3 patient data to identify DEFUSE 3 patients not meeting DAWN criteria (DEFUSE 3 non-DAWN). Reasons for DAWN exclusion in DEFUSE 3 were infarct core too large, National Institutes of Health Stroke Scale (NIHSS) score 6 to 9, and modified Rankin Scale score of 2. Subgroups were compared with the DEFUSE 3 non-DAWN and entire DEFUSE 3 cohorts. Results- There were 71 DEFUSE 3 non-DAWN patients; 31 patients with NIHSS 6 to 9, 33 with core too large, and 13 with premorbid modified Rankin Scale score of 2 (some patients met multiple criteria). For core-too-large patients, median 24-hour infarct volume was 119 mL (interquartile range, 74.6-180) versus 31.5 mL (interquartile range, 17.6-64.3) for core-not-too-large patients ( P<0.001). Complications and functional outcomes were similar between the groups. Thrombectomy in core-too-large patients compared with the remaining DEFUSE 3 non-DAWN patients conveyed benefit for functional outcome (odds ratio, 20.9; CI, 1.3-337.8). Comparing the NIHSS 6 to 9 group with the NIHSS ≥10 patients, modified Rankin Scale score 0 to 2 outcomes were achieved in 74% versus 22% ( P<0.001), with mortality in 6% versus 23% ( P=0.024), respectively. For patients with NIHSS 6 to 9 compared with the remaining DEFUSE 3 non-DAWN patients, thrombectomy trended toward a better chance of functional outcome (odds ratio, 1.86; CI, 0.36-9.529). Conclusions- Patients with pretreatment core infarct volumes <70 mL but too large for inclusion by DAWN criteria demonstrate benefit from endovascular therapy. More permissive pretreatment core thresholds in core-clinical mismatch selection paradigms may be appropriate. In contrast to data supporting a beneficial treatment effect across the full range of NIHSS scores in the entire DEFUSE 3 population, only a trend toward benefit of thrombectomy in patients with NIHSS 6 to 9 was found in this small subgroup.

In large clinical trials designed to determine efficacy of an experimental treatment, patients are enrolled with presence or absence of various risk factors, such as diabetes or history of atrial fibrillation. A treatment-by-risk factor interaction indicates that the treatment effect may depend on the risk factor presence or absence. It is important to identify such interaction, since a treatment may fail or cause adverse events in the presence of the risk. Although statistical methods exist to identify such interaction, they are underutilized in clinical stroke research. This paper reviews the notion of treatment-by-risk factor interaction and identifies two types of interaction, quantitative and qualitative, using a graphical technique and statistical testing. We illustrate how to avoid drawing the erroneous conclusions regarding the treatment effect on subgroups when failing to detect an interaction, and provide rigorous tools to estimate the treatment effect on subgroups when an interaction is observed. Applications are presented using the data collected from the NINDS t-PA stroke studies. In stroke clinical trials, a treatment-by-risk factor interaction must be considered if the data permit. The graphical approach provides a heuristic illustration of interactions. Qualitative interactions are more important than quantitative interactions on therapeutic conclusion. Results of NINDS t-PA stroke studies confirmed our previous conclusions on the treatment t-PA benefit within 3-h therapeutic window. No subgroup of patients would lead a physician to withhold the t-PA treatment.