Abstract
Spatial models enable understanding potential redistribution of marine resources associated with ecosystem drivers and climate change. Stock assessment platforms can incorporate spatial ...processes, but have not been widely implemented or simulation tested. To address this research gap, an international simulation experiment was organized. The study design was blinded to replicate uncertainty similar to a real‐world stock assessment process, and a data‐conditioned, high‐resolution operating model (OM) was used to emulate the spatial dynamics and data for Indian Ocean yellowfin tuna (
Thunnus albacares
). Six analyst groups developed both single‐region and spatial stock assessment models using an assessment platform of their choice, and then applied each model to the simulated data. Results indicated that across all spatial structures and platforms, assessments were able to adequately recreate the population trends from the OM. Additionally, spatial models were able to estimate regional population trends that generally reflected the true dynamics from the OM, particularly for the regions with higher biomass and fishing pressure. However, a consistent population biomass scaling pattern emerged, where spatial models estimated higher population scale than single‐region models within a given assessment platform. Balancing parsimony and complexity trade‐offs were difficult, but adequate complexity in spatial parametrizations (e.g., allowing time‐ and age‐variation in movement and appropriate tag mixing periods) was critical to model performance. We recommend expanded use of high‐resolution OMs and blinded studies, given their ability to portray realistic performance of assessment models. Moreover, increased support for international simulation experiments is warranted to facilitate dissemination of methodology across organizations.
We present Bourdieu's notions of field, capital, "habitus," and strategy and how these concepts apply today in light of academic capitalism using an empirical study of faculty work in one specific ...field in engineering that exemplifies current tendencies brought by academic capitalism. We conclude with a discussion of practical implications. (Contains 1 table.)
► Intra-jurisdictional vulnerability patterns influence statistical catch-at-age stock assessments. ► Models with spatially referenced parameters preferred using information criteria. ► Strong ...statistical evidence of improved model fit. ► Accounting for spatial population structure changed derived management parameters.
Stock assessments commonly allow parameters to vary across fishery or jurisdictional boundaries, often by treating each region as a unit stock. However, animals generally disperse in response to spatial habitat features to satisfy particular life history requirements, and these features are often not congruent with fishery or jurisdictional boundaries. Thus, populations are often spatially structured at scales distinct from those acknowledged in assessments. Furthermore, when the spatial structure arises from dispersal of a common pool of recruits, redefining unit stock boundaries may not adequately capture these dynamics. Here we test the utility of spatially referencing parameters (vulnerability and catchability) in a statistical catch-at-age stock assessment model as a simple approach to account for life history variation of walleye (
Sander vitreus) when information on explicit movement rates is unavailable. We apply several alternative assessment models to Lake Erie walleye – a population identified as displaying age-specific differences in the extent of dispersal from spawning grounds – to investigate the importance of accounting for spatial heterogeneity at ecologically important scales in stock assessments. Comparisons of the most parsimonious assessment models (based on a deviance information criterion) with and without spatially referenced parameters (by basin) highlighted the importance of estimating regional vulnerability and catchability. There was strong statistical evidence that incorporating spatially referenced parameters at a scale relevant to walleye dispersal patterns improved model fit, and the change altered estimates of stock size and fishing mortality. For example, estimates of total age-2 and older walleye abundance in the most recent year decreased by 16% (34% for ages 7 and older) and fully selected fishing mortality increased by 70% after incorporating walleye spatial population structure. These results emphasize the importance of considering spatial aspects in stock assessments at scales relevant to the life history of the species or group of species under consideration.
Changing ecosystem conditions present a challenge for the monitoring and management of living marine resources, where decisions often require lead-times of weeks to months. Consistent improvement in ...the skill of regional ocean models to predict physical ocean states at seasonal time scales provides opportunities to forecast biological responses to changing ecosystem conditions that impact fishery management practices. In this study, we used 8-month lead-time predictions of temperature at 250 m depth from the J-SCOPE regional ocean model, along with stationary habitat conditions (e.g., distance to shelf break), to forecast Pacific hake (Merluccius productus) distribution in the northern California Current Ecosystem. Using retrospective skill assessments, we found strong agreement between hake distribution forecasts and historical observations. The top performing models (based on out-of-sample skill assessments using the area-under-the-curve (AUC) skill metric) were a generalized additive model (GAM) that included shelf-break distance (i.e., distance to the 200 m isobath) (AUC = 0.813) and a boosted regression tree (BRT) that included temperature at 250 m depth and shelf-break distance (AUC = 0.830). An ensemble forecast of the top performing GAM and BRT models only improved out-of-sample forecast skill slightly (AUC = 0.838) due to strongly correlated forecast errors between models (r = 0.88). Collectively, our results demonstrate that seasonal lead-time ocean predictions have predictive skill for important ecological processes in the northern California Current Ecosystem and can be used to provide early detection of impending distribution shifts of ecologically and economically important marine species.
Abstract
BACKGROUND
Sport-related structural brain injury (SRSBI) is intracranial pathology incurred during sport. Management mirrors that of non-sport-related brain injury. An empirical vacuum ...exists regarding return to play (RTP) following SRSBI.
OBJECTIVE
To provide key insight for operative management and RTP following SRSBI using a (1) focused systematic review and (2) survey of expert opinions.
METHODS
A systematic literature review of SRSBI from 2012 to present in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and a cross-sectional survey of RTP in SRSBI by 31 international neurosurgeons was conducted.
RESULTS
Of 27 included articles out of 241 systematically reviewed, 9 (33.0%) case reports provided RTP information for 12 athletes. To assess expert opinion, 31 of 32 neurosurgeons (96.9%) provided survey responses. For acute, asymptomatic SRSBI, 12 (38.7%) would not operate. Of the 19 (61.3%) who would operate, midline shift (63.2%) and hemorrhage size > 10 mm (52.6%) were the most common indications. Following SRSBI with resolved hemorrhage, with or without burr holes, the majority of experts (>75%) allowed RTP to high-contact/collision sports at 6 to 12 mo. Approximately 80% of experts did not endorse RTP to high-contact/collision sports for athletes with persistent hemorrhage. Following craniotomy for SRSBI, 40% to 50% of experts considered RTP at 6 to 12 mo. Linear regression revealed that experts allowed earlier RTP at higher levels of play (β = –0.58, 95% CI –0.111, –0.005, P = .033).
CONCLUSION
RTP decisions following structural brain injury in athletes are markedly heterogeneous. While individualized RTP decisions are critical, aggregated expert opinions from 31 international sports neurosurgeons provide key insight. Level of play was found to be an important consideration in RTP determinations.
Mark-recapture methods were used to examine watershed-scale survival of coastal cutthroat trout (
Oncorhynchus clarkii clarkii
) from two headwater stream networks. A total of 1725 individuals (≥100 ...mm, fork length) were individually marked and monitored seasonally over a 3-year period. Differences in survival were compared among spatial (stream segment, subwatershed, and watershed) and temporal (season and year) analytical scales, and the effects of abiotic (discharge, temperature, and cover) and biotic (length, growth, condition, density, movement, and relative fish abundance) factors were evaluated. Seasonal survival was consistently lowest and least variable (years combined) during autumn (16 September - 15 December), and evidence suggested that survival was negatively associated with periods of low stream discharge. In addition, relatively low (-) and high (+) water temperatures, fish length (-), and boulder cover (+) were weakly associated with survival. Seasonal abiotic conditions affected the adult cutthroat trout population in these watersheds, and low-discharge periods (e.g., autumn) were annual survival bottlenecks. Results emphasize the importance of watershed-scale processes to the understanding of population-level survival.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Oncology media websites such as Oncology Live (OncLive) and Targeted Oncology (TargetedOnc) play an important role in the dissemination of oncology news to patients and clinicians; however, the ...quality of the content on these websites has not been assessed. Our study aimed to analyze content from these websites and assess financial conflicts of interest (FCOI) amongst speakers interviewed on these websites.
Articles published on OncLive and TargetedOnc during October 2021, were prospectively captured and analyzed. The primary outcome of our study was the quality of oncology news reporting in OncLive and TargetedOnc. We assessed the FCOI amongst speakers using data from Open Payments.
We examined 196 articles (OncLive 108, TargetedOnc 88). Limitations of cited research were reported in 7% (7/105) of OncLive and zero TargetedOnc articles. Benefit and risks in absolute numbers were reported in 28% (28/99) of OncLive and 16% (7/45) of TargetedOnc articles. Independent experts were quoted in 47% (51/108) and 51% (44/86) of the OncLive and TargetedOnc articles, respectively (Table 3). Pharmaceutical executives were quoted in 18% (20/108) and 11% (10/88) of OncLive and TargetedOnc articles, respectively. No FCOI disclosures were listed or reported for any articles. The mean general payment received from industry by United States physicians was $63,861 in 2019 and $39,639 in 2020.
Our study demonstrates low quality and potentially biased reporting of oncology news on OncLive and TargetedOnc. Careful safeguards, oversight and reporting of relevant FCOI are needed to maintain the quality and transparency of content being provided.
•Oncology news websites disseminating new findings are not subject to the same standards of peer-review as medical journals.•We found evidence of poor reporting, spin, and undisclosed financial conflicts of interest in oncology news articles.•Our findings question the effectiveness of Sunshine law; and the need for amendments to include payments via third parties.
To investigate effects of headwater logging on downstream coastal cutthroat trout (Oncorhynchus clarkii clarkii) populations, we monitored stream habitat and biotic indicators including biomass, ...abundance, growth, movement, and survival over 8 years using a paired-watershed approach. Reference and logged catchments were located on private industrial forestland on ∼60-year harvest rotation. Five clearcuts (14% of the logged catchment area) were adjacent to fishless portions of the headwater streams, and contemporary regulations did not require riparian forest buffers in the treatment catchment. Logging did not have significant negative effects on downstream coastal cutthroat trout populations for the duration of the sample period. Indeed, the only statistically significant response of fish populations following logging in fishless headwaters was an increase in late-summer biomass (g·m
−2
) of age-1+ coastal cutthroat trout in tributaries. Ultimately, the ability to make broad generalizations concerning effects of timber harvest is difficult because response to disturbance (anthropogenically influenced or not) in aquatic systems is complex and context-dependent, but our findings provide one example of environmentally compatible commercial logging in a regenerated forest setting.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Generating biomass-at-age indices for fisheries stock assessments with acoustic data collected by uncrewed surface vessels (USVs) has been hampered by the need to resolve acoustic backscatter with ...contemporaneous biological (e.g., age) composition data. To address this limitation, Pacific hake (
Merluccius productus
; “hake”) acoustic data were gathered from a USV survey (in 2019) and acoustic-trawl survey (ATS; 2019 and eight previous years), and biological data were gathered from fishery-dependent and non-target (i.e., not specifically targeting hake) fishery-independent sources (2019 and eight previous years). To overcome the lack of contemporaneous biological sampling in the USV survey, age class compositions were estimated from a generalized linear mixed spatio-temporal model (STM) fit to the fishery-dependent and non-target fishery-independent data. The validity of the STM age composition estimation procedure was assessed by comparing estimates to age compositions from the ATS in each year. Hake biomass-at-age was estimated from all combinations of acoustics (USV or ATS in 2019, ATS only in other years) and age composition information (STM or ATS in all years). Across the survey area, proportional age class compositions derived from the best STM differed from ATS observations by 0.09 on average in 2019 (median relative error (MRE): 19.45%) and 0.14 across all years (MRE: 79.03%). In data-rich areas (i.e., areas with regular fishery operations), proportional age class compositions from the STM differed from ATS observations by 0.03 on average in 2019 (MRE: 11.46%) and 0.09 across years (MRE: 54.96%). On average, total biomass estimates derived using STM age compositions differed from ATS age composition-based estimates by approximately 7% across the study period (~ 3% in 2019) given the same source of acoustic data. When biomass estimates from different sources of acoustic data (USV or ATS) were compared given the same source of age composition data, differences were nearly ten-fold greater (22% or 27%, depending on if ATS or STM age compositions were used). STMs fit to non-contemporaneous data may provide suitable information for assigning population structure to acoustic backscatter in data-rich areas, but advancements in acoustic data processing (e.g., automated echo classification) may be needed to generate viable USV-based estimates of biomass-at-age.
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