Fishing regulations, sexual dimorphism, and the life history of harvest

Freshwater recreational fisheries regulations are a vital tool for achieving social and ecological fisheries objectives. However, angler behavior and fish biology may interact to influence regulation efficacy in unexpected ways. We combined models of fish growth and angler behavior to explore how angler behavior interacts with fish life history to shape the probability of fish harvest given capture across ages, life stages, and sexes of walleye (Sander vitreus). Compared to females, males grew more quickly as juveniles, matured earlier, and reached smaller maximum sizes. Male walleye were therefore vulnerable to harvest for more of their reproductive lives than females because males spent more time at sizes where anglers were very likely to harvest them. We suggest that restricting harvest of large individuals in sexually dimorphic species may favor the survival of large, reproductive-aged females. Moreover, we show that combining models of fish growth and harvester behavior can provide insights into how harvest affects fish with complex life histories over the course of their lives. La réglementation relative aux pêches sportives en eau douce constitue un outil d’importance capitale pour l’atteinte des objectifs sociaux et écologiques des pêches. Les interactions des comportements des pêcheurs et de la biologie des poissons peuvent toutefois influencer l’efficacité de la réglementation de manière imprévue. Nous combinons des modèles de croissance des poissons et de comportement des pêcheurs afin d’examiner l’effet de l’interaction du comportement des pêcheurs et du cycle biologique des poissons sur la probabilité de récolte de poissons au vu des prises selon l’âge, de l’étape du cycle de vie et du sexe de dorés jaunes (Sander vitreus). Comparativement aux femelles, les mâles croissent plus vite quand ils sont juvéniles, arrivent à maturité plus tôt et atteignent des tailles maximums plus petites. Les dorés mâles sont donc plus vulnérables à la récolte pour une plus grande partie de leur vie reproductive que les femelles parce qu’ils passent plus de temps à des tailles qui les rendent plus susceptibles d’être récoltés par les pêcheurs. Nous suggérons que le fait de restreindre la récolte aux grands individus pour des espèces qui présentent un dimorphisme sexuel pourrait favoriser la survie des grandes femelles en âge de reproduction. Nous démontrons en outre que le jumelage de modèles de croissance des poissons et de comportement des pêcheurs peut fournir de l’information utile sur l’effet de la récolte sur les poissons aux cycles biologiques complexes au fil de leur vie

Negation and the functional sequence

There exists a general restriction on admissible functional sequences which prevents adjacent identical heads. We investigate a particular instantiation of this restriction in the domain of negation. Empirically, it manifests itself as a restriction the stacking of multiple negative morphemes. We propose a principled account of this restriction in terms of the general ban on immediately consecutive identical heads in the functional sequence on the one hand, and the presence of a Neg feature inside negative morphemes on the other hand. The account predicts that the stacking of multiple negative morphemes should be possible provided they are separated by intervening levels of structure. We show that this prediction is borne out

Global overview of the management of acute cholecystitis during the COVID-19 pandemic (CHOLECOVID study)

Background: This study provides a global overview of the management of patients with acute cholecystitis during the initial phase of the COVID-19 pandemic. Methods: CHOLECOVID is an international, multicentre, observational comparative study of patients admitted to hospital with acute cholecystitis during the COVID-19 pandemic. Data on management were collected for a 2-month study interval coincident with the WHO declaration of the SARS-CoV-2 pandemic and compared with an equivalent pre-pandemic time interval. Mediation analysis examined the influence of SARS-COV-2 infection on 30-day mortality. Results: This study collected data on 9783 patients with acute cholecystitis admitted to 247 hospitals across the world. The pandemic was associated with reduced availability of surgical workforce and operating facilities globally, a significant shift to worse severity of disease, and increased use of conservative management. There was a reduction (both absolute and proportionate) in the number of patients undergoing cholecystectomy from 3095 patients (56.2 per cent) pre-pandemic to 1998 patients (46.2 per cent) during the pandemic but there was no difference in 30-day all-cause mortality after cholecystectomy comparing the pre-pandemic interval with the pandemic (13 patients (0.4 per cent) pre-pandemic to 13 patients (0.6 per cent) pandemic; P = 0.355). In mediation analysis, an admission with acute cholecystitis during the pandemic was associated with a non-significant increased risk of death (OR 1.29, 95 per cent c.i. 0.93 to 1.79, P = 0.121). Conclusion: CHOLECOVID provides a unique overview of the treatment of patients with cholecystitis across the globe during the first months of the SARS-CoV-2 pandemic. The study highlights the need for system resilience in retention of elective surgical activity. Cholecystectomy was associated with a low risk of mortality and deferral of treatment results in an increase in avoidable morbidity that represents the non-COVID cost of this pandemic

Thyroarytenoid muscle responses to air pressure stimulation of the laryngeal mucosa in humans

Others have observed glottic adduction in response to air puff stimuli and suggested that this is a reliable indicator of laryngeal sensation. We undertook to determine whether the same thresholds are found if one uses either thyroarytenoid (TA) muscle responses or subjects\u27 reports of laryngeal sensation. We also studied the characteristics of TA responses to unilateral air pressure stimulation of the mucosa overlying the arytenoid cartilages. Ten normal volunteers provided button press responses to air pressure stimuli during bilateral TA electromyography. Similar thresholds were determined by reports of sensation as by electromyographic responses (p \u3c .0005). The early TA responses occurred either around 80 ms or around 125 ms after onset of the air puff, with equal frequency on the ipsilateral and contralateral sides. The TA muscle responses to air pressure stimulation differ in physiological characteristics from the laryngeal adductor reflex that occurs in response to electrical stimulation of the superior laryngeal nerve