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Effective management of freshwater fish habitat is essential to supporting healthy aquatic ecosystems and sustainable fisheries. In Canada, recent changes to the Fisheries Act enhanced the protection of fish habitat, but application of those provisions relies on sound scientific evidence. We employed collaborative research prioritization methods to identify scientific research questions that, if addressed, would significantly advance the management of freshwater fish habitat in Canada. This list was generated by a diverse group of freshwater fish experts, including substantial contributions from practitioners who administer provisions of the Fisheries Act. The research questions generated in this study identify priority topics for future research, while highlighting issues that could be addressed with different funding models. As a result, this study should support evidence-based management of Canada’s aquatic resources by identifying scientific knowledge gaps faced by practitioners, and suggesting mechanisms to address them. Given the important contribution of Canadian freshwater systems to global ecosystem values, and the similar scientific challenges facing fish habitat managers in other jurisdictions, this study is likely to have broad applicability.

The optimal timing for pursuing tracheostomy in patients with prolonged mechanical ventilation with either veno-arterial (VA) or veno-venous (VV) extracorporeal membrane oxygenation (ECMO) is a discussion of risk versus benefit. Depending on the etiology, cardiothoracic surgical patients carry some of the highest risk for respiratory failure postprocedure. Given that patients with end-stage cardiopulmonary status may be fraught with substantial comorbidities, it is critically important to manage the risk-benefit profile of performing a tracheostomy procedure on a patient requiring ECMO support. These cohorts have risk factors that may depend on each patient's inflammatory state, lung de-recruitment peri-procedure and postprocedure and bleeding requiring transfusions to name a few. We provide a descriptive analysis of ECMO patients on both VA and VV configurations who survived to hospital discharge receiving tracheostomy either during or after their ECMO course.A retrospective single-institutional study collected all consecutive patients age 18 and above who received any form of ECMO between 2016 and 2020. Five hundred forty-five patients were screened based on having received ECMO. Patients with mixed EMCO modality were excluded due to heterogeneity of disease process. A total of 521 patients received either VV or VA ECMO. A total of 54 patients received tracheostomy and had sufficiently clean data for analysis. Tracheostomy patients were compared based on survival to discharge, tracheostomy surgical complications, ECMO duration, ECMO configuration, inotrope and vasopressor use, transfusion rates, total ventilator days, total days on intravenous sedation, and history of cardiotomy or heart transplant were assessed. Baseline characteristics of race, age, gender, and body mass index (BMI) were also collected.A total of 54 patients received tracheostomy. Twenty-nine of those patients received tracheostomy during the course of their ECMO, of whom 13 were on VV ECMO, 16 on VA ECMO. Another 25 patients underwent tracheostomy after successful ECMO explant; 8 of those were VV ECMO with the remaining 17 were on VA ECMO before explantation, with mean delay to tracheostomy, 10 and 19 days after explant between both modalities, respectively. A statistically significantly greater proportion of VV ECMO patients received a tracheostomy at any point versus VA ECMO patients (25.93% vs. 8.35%, p ≤ .0001). No statistically significant difference was noted in timing of tracheostomy when stratified by EMCO modality (VA 51.51% after explant vs. VV 38.10% after explant, p = .33). There was a greater frequency of minor tracheostomy complications in patients who were on ECMO at the time of their tracheostomy (p = .014) than in those who received their tracheostomy after being explanted. However, these minor complications did not contribute to a change in survival to hospital discharge (p = .58). Similarly, the small number of major complications (n = 13) did not impair survival to hospital discharge (p = .84). Finally, mean duration of ECMO was longer in those who received tracheostomy during ECMO versus after ECMO. (488.45 vs. 259.72 h, p .01).Tracheostomy is known to increase patient mobility, clinical participation, and overall decrease in sedation use. Pursuing tracheostomy during ECMO is feasible, does not result in major bleeding, and is associated with only minor complications that overall do not decrease survival. While there is an increased duration of ECMO support in the tracheostomy cohort, this may be due to existing patient conditions, and may not be causal. Research is needed to further determine the external patient factors and specific timing to optimize both VV and VA ECMO courses.We hope that our analysis will pave the initial pathway for an evidence-based guideline on optimal timing of tracheostomy in ECMO patients, whether initiated during or after ECMO and taking into consideration ECMO configuration, its expected duration, and patient comorbidities.

Currently, wind turbine blades are designed following a safe-life paradigm where manufacturing defects and operational damages are not taken into account. However, industry competition steers innovation towards typical solutions to maximize the economical output. The harsh environment, especially for offshore wind turbines, significantly degrades the turbine structural integrity and its performance. One of the major factors that lowers energy production due to aerodynamic losses is the erosion of the leading edges. Nowadays this erosion is monitored visually, either directly or with drone-based camera systems. We expect a quantitative characterization of the current erosion state and long term degradation monitoring to provide crucial information for wind farm maintenance and possible recoating of wind turbine blades. In this project, a customized long-range laser line scanner is used to measure the profiles of the blades at distances of up to 2 m. Individual scans are assembled into a 3D point cloud which is processed and analysed for defects and erosion. Further in the project, a custom-developed heavy drone will be used to scan the blades offshore. Current results include the detection of eroded areas, impact damages and surface defects in laboratory conditions with the sensor positioned with a scanning frame. Two processing approaches, namely deterministic and machine learning are compared and benchmarked with an ambition to perform erosion detection at a submillimeter scale. The deterministic approach includes local analysis of the surface variation, thresholding and clustering of the defects. Present controlled conditions allow investigation of how predicted drone vibrations, possible water droplets and salt contamination affect the inspection in a real offshore environment. This development is done within the smart maintenance innovation project AIRTuB: Automatic Inspection and Repair of Turbine Blades where the inspection expertise is combined with drone and wind-turbine manufacturers to change the turbine design paradigm from safe life to damage-tolerant.

Autoimmune processes are now an increasingly recognized cause of acute and chronic pancreatitis. Autoimmune pancreatitis is a rare, benign pathology with two distinct clinicopathologic subtypes. The aim of this study was to compare the presentation, diagnostic considerations and outcomes of patients with biopsy-proven type 1 and 2 autoimmune pancreatitis (AIP).A retrospective review of the Queensland Health pathology database of histologically proven AIP was conducted. Parameters compared included demographics, diagnostic criterion and post-treatment outcomes.Twenty-three patients had a confirmed histological diagnosis of AIP (type 1 = 13, type 2 = 10). Patients with type 2 AIP were younger (median age 49 versus 59 years, P 0.05). There was no significant difference in gender distribution of disease at presentation. Type 2 AIP presented with significant increased focal pancreatic changes on cross-sectional imaging (80% versus 54%, P 0.05). Serum IgG4 levels were raised (1.40 g/L) in 69% of patients with type 1 AIP and not detected in type 2 (P 0.01). Concurrent underlying inflammatory bowel disease was present in a higher proportion of type 2 AIP (40% versus 15%, P 0.05). A significantly increased proportion of patients with type 2 AIP underwent surgical resection (70% versus 30%, P 0.05). Conservative management was utilized in more patients with type 1 disease (54% versus 30%). On follow-up, two patients have experienced symptomatic relapse at 6-18 months.Diagnostic challenges do exist and clinicians must suspect 2 type AIP in young, serum IgG4-negative inflammatory bowel disease patients with recurrent pancreatitis.

Background Free-floating thrombus in the internal carotid artery (ICA) has traditionally been treated via an open surgical approach through a longitudinal incision and exposure similar to that for carotid endarterectomy (CEA). In this case report, we present a novel use of transcarotid artery revascularization (TCAR) for the treatment of recurrent carotid stenosis associated with free-floating ICA thrombus. Case Description We describe a 67-year-old female who presented with a diagnosis of right hemispheric stroke in evolution and prior history of right CEA and a mechanical mitral valve. Imaging confirmed high-grade recurrent stenosis of the right ICA with free-floating thrombus. TCAR was utilized to repair both the recurrent stenosis and the thrombus. Conclusions Redo CEA in the face of recurrent stenosis is a challenging clinical scenario, which in this instance, was further complicated by the presence of free-floating thrombus and active anticoagulation due to a mechanical mitral valve. This case report describes the successful management of ICA thrombus and restenosis with the novel use of TCAR.

Studies of high-multiplicity, tightly-packed planetary systems suggest that dynamical instabilities are common and affect both the orbits and planet structures, where the compact orbits and typically low densities make physical collisions likely outcomes. Since the structure of many of these planets is such that the mass is dominated by a rocky core, but the volume is dominated by a tenuous gas envelope, the sticky-sphere approximation, used in dynamical integrators, may be a poor model for these collisions. We perform five sets of collision calculations, including detailed hydrodynamics, sampling mass ratios and core mass fractions typical in Kepler Multis. In our primary set of calculations, we use Kepler-36 as a nominal remnant system, as the two planets have a small dynamical separation and an extreme density ratio. We use an N-body code, Mercury 6.2, to integrate initially unstable systems and study the resultant collisions in detail. We use these collisions, focusing on grazing collisions, in combination with realistic planet models created using gas profiles from Modules for Experiments in Stellar Astrophysics and core profiles using equations of state from Seager et al. (2007), to perform hydrodynamic calculations, finding scatterings, mergers, and even a potential planet-planet binary. We dynamically integrate the remnant systems, examine the stability, and estimate the final densities, finding the remnant densities are sensitive to the core masses, and collisions result in generally more stable systems. We provide prescriptions for predicting the outcomes and modeling the changes in mass and orbits following collisions for general use in dynamical integrators., Comment: 29 pages, 13 figures, Accepted for publication in ApJ

Using data from the International Social Survey Program and the World Values Survey about current and former religious adherence, we calculate country-level religious-conversion rates for 40 countries. Drawing upon a theoretical model based on rational individual choice, we posit that the frequency of religious conversion depends on the cost of switching and the cost of having the "wrong" religion. Findings accord with several hypotheses: religious-conversion rates are positively related to religious pluralism, gauged by adherence shares; negatively related to government restrictions on religious conversion; positively related to levels of education; and negatively related to a history of Communism. Conversion rates are not related to per capita GDP, the presence of state religion, and the extent of religiosity. Effects from the types of religious adherence are minor, except for the negative effect of Muslim adherence.

Disruptive innovation has brought affordability and convenience to customers in a variety of industries. However, health care remains expensive and inaccessible to many because of the lack of business-model innovation. This paper explains the theory of disruptive innovation and describes how disruptive technologies must be matched with innovative business models. The authors present a framework for categorizing and developing business models in health care, followed by a discussion of some of the reasons why disruptive innovation in health care delivery has been slow.

Most countries in the periphery specialized in the export of just a handful of primary products for most of their history. Some of these commodities have been more price volatile than others, and those with more volatility have grown much more slowly relative to the industrial leaders and to other primary product exporters. This fact helps explain the growth puzzle noted by Easterly, Kremer, Pritchett and Summers more than a decade ago: that the contending fundamental determinants of growth—institutions, geography and culture—exhibit far more persistence than do the growth rates they are supposed to explain. Using a new panel database for 35 countries, this paper estimates the impact of terms of trade volatility and secular change on country performance between 1870 and 1939. Volatility was much more important for growth than was secular change and accounts for a substantial degree of the divergence in incomes within the sample of small, commodity-dependent ‘Periphery’ nations as well as under-performance of the Periphery as a whole relative to such nations as the US and Western Europe, or ‘Core’. One channel of impact seems to be the adverse effect of volatility on foreign investment. It appears that the terms of trade effects were asymmetric between Core and Periphery.

Massive stars are usually found in binaries, and binaries with periods less than 10 days may have a preference for near equal component masses. In this paper we investigate the evolution of these binaries all the way to contact and the possibility that these systems can be progenitors of double neutron star binaries. The small orbital separations of observed double neutron star binaries suggest that the progenitor systems underwent a common envelope phase at least once during their evolution. Bethe & Brown (1998) proposed that massive binary twins will undergo a common envelope evolution while both components are ascending the red giant branch or asymptotic giant branch simultaneously, also known as double-core evolution. Using models generated from the stellar evolution code Evolve Zero Age Main Sequence, we determine the range of mass ratios resulting in both components simultaneously ascending the RGB or AGB as a function of the difference in birth times, t. We find that, even for a generous t=5 Myr, the minimum mass ratio qmin=0.933 for an 8 Solar Mass primary and increases for larger primaries. We use a hydrodynamics code, StarSmasher, to study specifically the evolution of q=1 common envelope systems as a function of initial component mass, age, and orbital separation. We find the dynamical stability limit, the largest orbital separation where the binary becomes dynamically unstable, as a function of the component mass and age. Finally, we calculate the efficiency of ejecting matter during the inspiral phase to extrapolate the properties of the remnant binary from our numerical results, assuming the common envelope is completely ejected. We find that for the nominal core masses, there is a minimum orbital separation for a given component mass such that the helium cores survive common envelope evolution in a tightly bound binary and are viable progenitors for double neutron stars., 51 pages, 26 figures, accepted for publication in ApJ

We calculate and analyze the distribution of period ratios observed in systems of Kepler exoplanet candidates including studies of both adjacent planet pairs and all planet pairs. These distributions account for both the geometrical bias against detecting more distant planets and the effects of incompleteness due to planets missed by the data reduction pipeline. In addition to some of the known features near first-order mean-motion resonances (MMR), there is a significant excess of planet pairs with period ratios near 2.2. The statistical significance of this feature is assessed using Monte Carlo simulation. We also investigate the distribution of period ratios near first-order MMR and compare different quantities used to measure this distribution. We find that beyond period ratios of ~2.5, the distribution of all period ratios follows a power-law with an exponent -1.26 +/- 0.05. We discuss implications that these results may have on the formation and dynamical evolution of Kepler-like planetary systems---systems of sub-Neptune/super-Earth planets with relatively short orbital periods., Comment: 20 pages, many figures, MNRAS accepted

Cholecystokinin (CCK) is known to rapidly and transiently increase both [Ca2+]i and autonomous CaM kinase II activity in rat pancreatic acini. Because induction of autonomous activity may involve intramolecular autophosphorylation, the effects of protein phosphatase inhibitors were examined. None of the inhibitors tested (okadaic acid, calyculin A, and cyclosporin A) affected basal activity. Okadaic acid, a potent inhibitor of PP2A and weaker inhibitor of PP1, increased the peak autonomous activity by 30% over the level normally induced by CCK alone, while calyculin A, a potent inhibitor of both PP1 and PP2A, showed an even greater increase of 97%. Both inhibitors also delayed the decline of autonomous activity and calyculin A had a more potent effect than okadaic acid. Cyclosporin A, an inhibitor of PP2B, had no effect. The data indicate that PP1 may be involved in the dephosphorylation of CaMK II and decline of autonomous activity.

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Although the mask pattern created by fine ebeam writing is four times larger than the wafer pattern, the mask proximity effect from ebeam scattering and etch is not negligible. This mask proximity effect causes mask-CD errors and consequently wafer-CD errors after the lithographic process. It is therefore necessary to include the mask proximity effect in optical proximity correction (OPC). Without this, an OPC model can not predict the entire lithography process correctly even using advanced optical and resist models. In order to compensate for the mask proximity effect within OPC a special model is required along with changes to the OPC flow. This article presents a method for producing such a model and OPC flow and shows the difference in results when they are used.

Colorectal cancer is one of the three most frequent causes of cancer deaths in men and women in Europe and North America. Diagnosis and resection of adenomas has convincingly demonstrated its utility in diminishing colorectal cancer incidence. Therefore, colonoscopy is now the gold standard for colorectal cancer screening. But it is also known that colonoscopy effectiveness varies among endoscopists. Among different quality indicators, the most used is the adenoma detection rate (ADR) which is the percentage of average-risk patients for colorectal cancer who are found to have at least one adenoma or adenocarcinoma during a screening colonoscopy. There is compelling evidence supporting an inverse correlation between ADR and interval colorectal cancer (cancer found after a screening colonoscopy). Many factors such as quality of precolonoscopy preparation, additional observers, manoeuvres with the endoscope (second view, retroflexion, water inflation rather than air), time spent during withdrawal, changes in patient position, fold-flattener devices, new imaging or endoscopic modalities and use of intravenous or through the scope sprayed drugs, have been studied and developed with the aim of increasing the ADR. This reviews discusses these factors, and the current evidence, to “see better” in the colon and optimize ADR.

Questions about current and prior religion adherence from the International Social Survey Program and the World Values Survey allow us to calculate country-level religious-conversion rates for 40 countries. These conversion rates apply to religion adherence classified into eight major types. In a theoretical model based on rational individual choice, the frequency of religious conversion depends on factors that influence the cost of switching and the cost of having the "wrong" religion. Empirical findings for a panel of countries accord with several hypotheses: religious-conversion rates are positively related to religious pluralism, gauged by adherence shares; negatively related to government restrictions on religious conversion; positively related to levels of education; and negatively related to a history of Communism. Conversion rates are not much related to per capita GDP, the presence of state religion, and the extent of religiosity. Effects from the type of religion adherence are minor, except for a negative effect from Muslim adherence. The empirical results are robust to alternative specifications of the religion groupings used to construct the conversion rates.

When local cost discovery generates knowledge spillovers, specialization patterns become partly indeterminate and the mix of goods that a country produces may have important implications for economic growth. We demonstrate this propo- sition formally and adduce some empirical support for it. We construct an index of the "income level of a country's exports," document its properties, and show that it predicts subsequent economic growth.

When local cost discovery generates knowledge spillovers, specialization patterns become partly indeterminate and the mix of goods that a country produces may have important implications for economic growth. We demonstrate this proposition formally and adduce some empirical support for it. We construct an index of the 'income level of a country's exports,' document its properties, and show that it predicts subsequent economic growth.

Most countries in the periphery specialized in the export of just a handful of primary products for most of their history. Some of these commodities have been more volatile than others, and those with more volatile prices have grown slowly relative both to the industrial leaders and to other primary product exporters. This fact helps explain the growth puzzle noted by Easterly, Kremer, Pritchett and Summers more than a decade ago: that the contending fundamental determinants of growth - institutions, geography and culture - exhibit far more persistence than do the growth rates they are supposed to explain. Using a new panel database for 35 countries, this paper estimates the impact of terms of trade volatility and secular change on country performance between 1870 and 1939. Volatility was much more important for accumulation and growth than was secular change. Additionally, both effects were asymmetric between Core and Periphery, findings that speak directly to the terms of trade debates that have raged since Prebisch and Singer wrote more than 50 years ago. The paper also investigates one channel of impact, and finds that foreign capital inflows declined steeply where commodity prices were volatile.

The contending fundamental determinants of growth - institutions, geography and culture - exhibit far more persistence than do the growth rates they are supposed to explain. So, what exogenous shocks might account for the variance around those persistent fundamentals? The terms of trade seems to be one good place to look. Using a panel data base for 35 countries, this paper estimates the impact of terms of trade volatility and secular change between 1870 and 1938. Authors find that volatility was much more important than secular change. Additionally, both effects were asymmetric between core and periphery, findings that speak directly to the terms of trade debates that have raged since Prebisch and Singer wrote more than 50 years ago.

The contending fundamental determinants of growth -- institutions, geography and culture --exhibit far more persistence than do the growth rates they are supposed to explain. So, what exogenous shocks might account for the variance around those persistent fundamentals? The terms of trade seems to be one good place to look. Using a panel data base for 35 countries, this paper estimates the impact of terms of trade volatility and secular change between 1870 and 1938. We find that volatility was much more important than secular change. Additionally, both effects were asymmetric between core and periphery, findings that speak directly to the terms of trade debates that have raged since Prebisch and Singer wrote more than 50 years ago.

Accumulating evidence has suggested the protective role of HDL in cardiovascular disease processes. Calcification is a common feature of atherosclerotic lesions and contributes to cardiovascular complications due to the loss of aortic resilience and function. Recent studies have suggested that vascular calcification shares several features with skeletal bone formation at the cellular and molecular levels. These include the presence of osteoblast-like calcifying vascular cells in the artery wall that undergo osteoblastic differentiation and calcification in vitro. We hypothesized that HDL may also protect against vascular calcification by regulating the osteogenic activity of these calcifying vascular cells. When treated with HDL, alkaline phosphatase activity, a marker of osteogenic differentiation of osteoblastic cells, was significantly reduced in those cells. Prolonged treatment with HDL also inhibited calcification of these cells, further supporting the antiosteogenic differentiation property of HDL when applied to vascular cells. Furthermore, HDL inhibited the osteogenic activity that was induced by inflammatory cytokines interleukin (IL)-1β and IL-6 as well as by minimally oxidized LDL. HDL also partially inhibited the IL-6-induced activation of signal transducer and activator of transcription 3 in calcifying vascular cells, suggesting that HDL may inhibit cytokine-induced signal transduction pathways. The inhibitory effects of HDL were mimicked by lipids extracted from HDL but not by HDL-associated apolipoproteins or reconstituted HDL. Furthermore, oxidation of HDL rendered it pro-osteogenic. Taken together, these results suggest that HDL regulates the osteoblastic differentiation and calcification of vascular cells and that vascular calcification may be another target of HDL action in the artery wall.