Demographic and risk analyses of spiny dogfish (Squalus suckleyi) in the Gulf of Alaska using age- and stage-based population models

2011 ◽  
Vol 62 (12) ◽  
pp. 1395 ◽  
Author(s):  
Cindy A. Tribuzio ◽  
Gordon H. Kruse
Keyword(s):  
Input Parameter ◽  
Gulf Of Alaska ◽  
Spiny Dogfish ◽  
Fishing Mortality ◽  
Sustainable Harvest ◽  
Demographic Models ◽  
The World ◽  
Slow Growing ◽  
Cohort Analyses ◽  
Modelling Approach

Demographic models are useful tools for assessing data-limited species and may be an appropriate alternative to cohort analyses for sharks due to their long-lived, slow-growing nature. In this study, age- and stage-based demographic analyses were conducted to examine the intrinsic rebound potential (r) and potential risk of fishing for spiny dogfish (Squalus suckleyi) in the Gulf of Alaska. Monte Carlo simulations were conducted to incorporate input parameter uncertainty. For an unfished population, r was estimated to be 0.02–0.03 year–1. Fishing mortalities (F) of F = 0.04 and 0.03 (age- and stage-based models respectively), resulted in r = 0, indicating that populations fished at higher F are not sustainable. Harvest strategies targeting juveniles (age-based model) and subadults (stage-based model) caused the highest risk of the population falling below defined thresholds (BMSY, B40% and B50%) after 20 years. The age- and stage-based models provided similar estimates of r and sustainable fishing mortality, suggesting that the stage-based model is an appropriate substitute for the age-based model in this case. S. suckleyi and the closely related S. acanthias are often harvested around the world and this modelling approach could be useful to the management of these species and other sharks where data is limited.

scholarly journals A study on the numerical modelling of UHPFRC-strengthened members

2018 ◽  
Vol 199 ◽  
pp. 09001
Author(s):  
Renaud Franssen ◽  
Serhan Guner ◽  
Luc Courard ◽  
Boyan Mihaylov
Keyword(s):  
Numerical Modelling ◽  
High Performance ◽  
Concrete Structures ◽  
Concrete Members ◽  
High Durability ◽  
Tension Tests ◽  
The World ◽  
Aging Infrastructure ◽  
New Generation ◽  
Modelling Approach

The maintenance of large aging infrastructure across the world creates serious technical, environmental, and economic challenges. Ultra-high performance fibre-reinforced concretes (UHPFRC) are a new generation of materials with outstanding mechanical properties as well as very high durability due to their extremely low permeability. These properties open new horizons for the sustainable rehabilitation of aging concrete structures. Since UHPFRC is a young and evolving material, codes are still either lacking or incomplete, with recent design provisions proposed in France, Switzerland, Japan, and Australia. However, engineers and public agencies around the world need resources to study, model, and rehabilitate structures using UHPFRC. As an effort to contribute to the efficient use of this promising material, this paper presents a new numerical modelling approach for UHPFRC-strengthened concrete members. The approach is based on the Diverse Embedment Model within the global framework of the Disturbed Stress Field Model, a smeared rotating-crack formulation for 2D modelling of reinforced concrete structures. This study presents an adapted version of the DEM in order to capture the behaviour of UHPFRC by using a small number of input parameters. The model is validated with tension tests from the literature and is then used to model UHPFRC-strengthened elements. The paper will discuss the formulation of the model and will provide validation studies with various tests of beams, columns and walls from the literature. These studies will demonstrate the effectiveness of the proposed modelling approach.

scholarly journals Adeloye-Odeku Disease in Irrua, South-South Nigeria

2019 ◽  
pp. 431-437
Author(s):  
E. Morgan ◽  
C. O. Okwumezie ◽  
G. C. Akasike ◽  
E A. Morgan
Keyword(s):  
Dermoid Cyst ◽  
Outpatient Clinic ◽  
Benign Lesion ◽  
Adult Life ◽  
Anterior Fontanelle ◽  
Group Counselling ◽  
Health Institution ◽  
The World ◽  
Rare Lesion ◽  
Slow Growing

First described in a publication by two Nigerian Neurosurgeons, Adeloye A and Odeku EL, in 1971, Adeloye-Odeku disease is a solitary congenital subgaleal inclusion dermoid cyst of the anterior fontanelle. This rare lesion, which makes up about 0.1-0.5% of all cranial tumours and 0.2% of all inclusion cysts, was initially thought to be found only in Africans. However, further reports have shown it to have a universal occurrence, as it has been reported in Caucasians, Chinese, Indians, and other part of the world. This lesion is also known as Congenital inclusion dermoid cyst (CIDS), is a benign slow-growing lesion, and if untreated, may persist to adult life. This article gives a highlight of the disease and its management and goes further to report 3 cases of this rare benign lesion seen in Irrua, South-South Nigeria, a rural, low-resource tertiary health institution. Incidentally and interestingly, all three cases presented within three consecutive months (January-March, 2019) at the neurosurgery outpatient clinic. Being uncomplicated cases, private and group counselling was done. The parents of the patients were much more reassured and relieved from their anxieties seeing others with similar problem. They were all worked up for surgery at different dates, had excision of the cysts with no complication and are currently being followed at the outpatient clinic. 

Biology and Management of Dogfish Sharks

2009 ◽  
Keyword(s):  
Management System ◽  
Active Management ◽  
Spiny Dogfish ◽  
The West ◽  
Individual Transferable Quotas ◽  
Annual Basis ◽  
Integration Program ◽  
The World ◽  
Improve Compliance ◽  
Key Issues

Abstract.—The fishery for spiny dogfish <em>Squalus acanthias </em>within British Columbia (B.C.) has fluctuated greatly over the past 150 years. During the 1930s and 1940s it was one of the most valuable fisheries on the West Coast. Active management of this fishery began in 1977 after Canada extended its exclusive economic zone to 200 mi. The management of Pacific groundfish fisheries, including dogfish, is complex, and is further complicated by serious conservation concerns. Bycatch issues and the lack of full catch monitoring have been of particular concern. As a result, Fisheries and Oceans Canada (DFO) approached groundfish industry representatives to develop a plan to address these key issues. A program to make individual fishers more accountable for their harvest, to improve compliance with the DFO’s selective fishing and fishery monitoring policies, and to be consistent with Pacific fisheries reform was developed. This integration program was implemented in 2006 for commercial groundfish fisheries within B.C. As a result, at-sea monitoring was maximized to 100% and individual transferable quotas within each fishery allow fishermen to account for their groundfish bycatch on an annual basis. This new management system could help pave the way for other fisheries around the world to learn, adjust accordingly, and implement similar regimes.

Meningiomas

2018 ◽  
Author(s):  
K. E. Hovinga ◽  
Y. Esquenazi ◽  
P. H. Gutin
Keyword(s):  
Treatment Strategies ◽  
Brain Structures ◽  
World Health ◽  
Spinal Tumors ◽  
Central Nervous System Tumors ◽  
Clinical Scenarios ◽  
The World ◽  
Specific Factors ◽  
Health Organization ◽  
Slow Growing

Meningiomas are the most common primary central nervous system tumors and account for about one third of all primary brain and spinal tumors. They are classified according to the World Health Organization into 3 groups (I–III). Treatment strategies range from observation, surgery, and/or a radiation therapy. Many meningiomas are slow growing and discovered incidentally. Symptoms can vary widely, depending on the location. Patient’s specific factors and the location of the meningioma in relation to critical brain structures are all important factors in determining the optimal treatment. This chapter presents common clinical scenarios of meningioma. Differential diagnosis, perioperative workup, surgical nuances, and postoperative complications are discussed.

Modeling of the spatial distribution of Pacific spiny dogfish (Squalus suckleyi) in the Gulf of Alaska using generalized additive and generalized linear models

2013 ◽  
Vol 70 (9) ◽  
pp. 1372-1385 ◽  
Author(s):  
Jason R. Gasper ◽  
Gordon H. Kruse
Keyword(s):  
Spatial Distribution ◽  
Generalized Linear Models ◽  
Linear Models ◽  
Negative Binomial ◽  
Fish Habitat ◽  
Additive Model ◽  
Gulf Of Alaska ◽  
Spiny Dogfish ◽  
Essential Fish Habitat ◽  
Mortality Estimation

The Pacific spiny dogfish (Squalus suckleyi) is a common bycatch species in the Gulf of Alaska. Their spatial distribution is poorly understood, as most catch is discarded at sea. We analyzed spiny dogfish spatial distribution from fishery-dependent and -independent observations of longline gear between 1996 and 2008 using generalized additive and generalized linear models. Poisson, negative binomial, and quasi-Poisson error structures were investigated; the quasi-Poisson generalized additive model fit best. Models showed that spiny dogfish catches were concentrated east of Kodiak Island in waters ≤100 m deep. Results facilitate design of future spiny dogfish assessment surveys and identification of areas in which to focus at-sea observations for fishing mortality estimation, and provide the basis for first-ever designation of spiny dogfish essential fish habitat, despite US legal requirements for essential fish habitat designations since 1996. Identified areas of high bycatch may expedite spatial management by indicating areas in which directed spiny dogfish fisheries could be focused or, conversely, areas in which heightened conservation and catch accounting efforts would be most effective to prevent overfishing of this long-lived, late-maturing species.

scholarly journals Covid-19 trajectories – Monitoring pandemic in the worldwide context

2020 ◽  
Author(s):  
Henry Loeffler-Wirth ◽  
Maria Schmidt ◽  
Hans Binder
Keyword(s):  
Regional Differences ◽  
Dynamic State ◽  
Monitoring Tool ◽  
Removal Rates ◽  
Death Rates ◽  
The World ◽  
Slow Growing ◽  
Pharmaceutical Interventions ◽  
Curve Tracking ◽  
Country Specific

AbstractBackgroundCovid-19 pandemic is developing worldwide with common dynamics but also with partly marked differences between regions and countries. They are not completely understood, but presumably, provide one clue to find ways to mitigate epidemics until exit strategies to its eradication become available.MethodWe provide a monitoring tool available at www.izbi.de. It enables inspection of the dynamic state of the epidemic in 187 countries using trajectories. They visualize transmission and removal rates of the epidemic and this way bridge epi-curve tracking with modelling approaches.ResultsExamples were provided which characterize state of epidemic in different regions of the world in terms of fast and slow growing and decaying regimes and estimate associated rate factors. Basic spread of the disease associates with transmission between two individuals every two-three days on the average. Non-pharmaceutical interventions decrease this value to up to ten days where ‘complete lock down’ measures are required to stop the epidemic. Comparison of trajectories revealed marked differences between the countries regarding efficiency of measures taken against the epidemic. Trajectories also reveal marked country-specific dynamics of recovery and death rates.ConclusionsThe results presented refer to the pandemic state in May 2020 and can serve as ‘working instruction’ for timely monitoring using the interactive monitoring tool as a sort of ‘seismometer’ for the evaluation of the state of epidemic, e.g., the possible effect of measures taken in both, lock-down and lock-up directions. Comparison of trajectories between countries and regions will support developing hypotheses and models to better understand regional differences of dynamics of Covid-19.

scholarly journals Preserving grapevine variety Fioletoviy Ranniy in the collection in vitro

2021 ◽  
Vol 273 ◽  
pp. 01007
Author(s):  
Valentina Puzirnova ◽  
Natalia Doroshenko
Keyword(s):  
Biodiversity Conservation ◽  
Sustainable Management ◽  
Future Generations ◽  
Ex Situ ◽  
Grapevine Variety ◽  
The World ◽  
History Of ◽  
Slow Growing

The paper is devoted to the problem of plant biodiversity conservation. This problem is acute all over the world. Lower Don Region has a centuries old history of viticulture and winemaking. There are many valuable vine varieties which are worthy of preservation for future generations. Classical methods no longer cope with this task. Applying advances of biotechnology in addition to traditional methods of ex situ and in situ biodiversity conservation allows sustainable management of genetic resources. This article summarizes the study of methods for creation slow growing collection for grapevine variety Fioletoviy Ranniy. Keeping plants in a slow-growing collection is one of the best ways to preserve biodiversity. This study analyzed the effect of various media compounds on vigor of vine in order to elongate the time between replantings.

scholarly journals Bacterial Angular Leafspot Disease of Strawberry: Search for Resistance

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 831B-831
Author(s):  
John L. Maas ◽  
Gene J. Galletta
Keyword(s):  
North America ◽  
Chemical Control ◽  
Practical Method ◽  
Xanthomonas Fragariae ◽  
The World ◽  
Systemic Nature ◽  
Slow Growing ◽  
Resistant Genotypes ◽  
Diploid Strawberry

Bacterial angular leafspot disease (BALD) of strawberry, caused by Xanthomonas fragariae, a slow-growing and often difficult pathogen to isolate from infected plants, is most commonly manifested as small discrete, angular, translucent lesions on leaves and sepals. As the bacteria infect systemically, plants may wilt and die. BALD has become increasingly important in North America and other strawberry-growing areas of the world. The systemic nature of the pathogen also is cause for concern with international shipment of strawberry plants, especially because there is no practical method for determining the presence of the bacteria in symptomless, infected plants, nor is there a practical method of chemical control. All cultivars of Fragaria × ananassa (8×) are susceptible to BALD, although a range of susceptibility is often apparent in plantings. Resistant genotypes have been reported among clones of F. virginiana (8×), F. moschata (6×), and F. vesca (2×). A program has been initiated to evaluate native octoploid and diploid strawberry germplasm for resistance to BALD.

scholarly journals Geomechanical Modelling of Railroad Ballast: A Review

2019 ◽  
Author(s):  
Yahia Alabbasi ◽  
Mohammed Hussein
Keyword(s):  
Mechanical Behavior ◽  
Mechanical Behaviour ◽  
Large Scale ◽  
Significant Contribution ◽  
State Of The Art ◽  
The State ◽  
The World ◽  
Modelling Approach ◽  
Main Material ◽  
Modelling Approaches

AbstractTraditional ballasted tracks have been used intensively around the world with ballast as the main material for tracks. Ballast has a significant contribution to the track alignment, stability and sustainability. After service, ballast deforms and degrades. Periodic ballast maintenance is needed which is a time and cost expensive activity. Understanding the mechanical behaviour of railroad ballast leads to better design and efficient maintenance. From the literature, there are two main approaches used to understand the mechanical behaviour of railroad ballast; large scale experimental and modelling. This paper aims to review the state of the art of literature on the modelling approaches used to understand ballast mechanical behaviour. It discusses the key findings from each modelling approach in understanding ballast mechanical behavior. It presents the main concerns and limitations of each modelling approach from different perspectives related to ballast modelling. It summarizes the limitations, gaps and gaps’ developments of the researches used to understand ballast behaviour via modelling approach.

Fast and Slow-Growing Products in World Trade

1963 ◽  
Vol 25 ◽  
pp. 22-39 ◽  
Keyword(s):  
World Trade ◽  
Industrial Development ◽  
New Product ◽  
Dramatic Effect ◽  
The World ◽  
Relative Decline ◽  
New Industry ◽  
Slow Growing

The pattern of world trade in manufactures is changing constantly as industrial development goes on. Indeed, the rise of new industries and the relative decline of old ones may have a more dramatic effect on the composition of world trade than on that of home output. Typically, when a new industry is established, it begins in one or two countries. For some years, these countries will be the only suppliers of the world, and exports will rise faster than production. But as the industry becomes established more and more countries will introduce it; exports of the product will begin to rise more slowly than total world exports, and some new product or group of products will take its place as the fastest-growing element in world trade.

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