17. Population Trends and Limiting Factors in Boiga irregularis

Migratory species can experience limiting factors at different locations and during different periods of their annual cycle. In migratory birds, these factors may even occur in different hemispheres. Therefore, identifying the distribution of populations throughout their annual cycle (i.e., migratory connectivity) can reveal the complex ecological and evolutionary relationships that link species and ecosystems across the globe and illuminate where and how limiting factors influence population trends. A growing body of literature continues to identify species that exhibit weak connectivity wherein individuals from distinct breeding areas co-occur during the nonbreeding period. A detailed account of a broadly distributed species exhibiting strong migratory connectivity in which nonbreeding isolation of populations is associated with differential population trends remains undescribed. Here, we present a range-wide assessment of the nonbreeding distribution and migratory connectivity of two broadly dispersed Nearctic-Neotropical migratory songbirds. We used geolocators to track the movements of 70Vermivorawarblers from sites spanning their breeding distribution in eastern North America and identified links between breeding populations and nonbreeding areas. Unlike blue-winged warblers (Vermivora cyanoptera), breeding populations of golden-winged warblers (Vermivora chrysoptera) exhibited strong migratory connectivity, which was associated with historical trends in breeding populations: stable for populations that winter in Central America and declining for those that winter in northern South America.

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Effects of sterilization modes on the mechanical strengths of plaster of paris implants

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100156432 ◽

1989 ◽

Vol 47 ◽

pp. 890-891

Author(s):

K. Cowden ◽

B. Giammara ◽

T. Devine ◽

J. Hanker

Keyword(s):

Gamma Radiation ◽

Calcium Sulfate ◽

Significant Loss ◽

Potassium Sulfate ◽

Limiting Factors ◽

Radiation Sterilization ◽

Plaster Of Paris ◽

Hardness Tester ◽

Dry Heat ◽

Calcium Sulfate Hemihydrate

Plaster of Paris (calcium sulfate hemihydrate, CaSO4. ½ H2O) has been used as a biomedical implant material since 1892. One of the primary limiting factors of these implants is their mechanical properties. These materials have low compressive and tensile strengths when compared to normal bone. These are important limiting factors where large biomechanical forces exist. Previous work has suggested that sterilization techniques could affect the implant’s strength. A study of plaster of Paris implant mechanical and physical properties to find optimum sterilization techniques therefore, could lead to a significant increase in their application and promise for future use as hard tissue prosthetic materials.USG Medical Grade Calcium Sulfate Hemihydrate Types A, A-1 and B, were sterilized by dry heat and by gamma radiation. Types A and B were additionally sterilized with and without the setting agent potassium sulfate (K2SO4). The plaster mixtures were then moistened with a minimum amount of water and formed into disks (.339 in. diameter x .053 in. deep) in polyethylene molds with a microspatula. After drying, the disks were fractured with a Stokes Hardness Tester. The compressive strengths of the disks were obtained directly from the hardness tester. Values for the maximum tensile strengths σo were then calculated: where (P = applied compression, D = disk diameter, and t = disk thickness). Plaster disks (types A and B) that contained no setting agent showed a significant loss in strength with either dry heat or gamma radiation sterilization. Those that contained potassium sulfate (K2SO4) did not show a significant loss in strength with either sterilization technique. In all comparisons (with and without K2SO4 and with either dry heat or gamma radiation sterilization) the type B plaster had higher compressive and tensile strengths than that of the type A plaster. The type A-1 plaster however, which is specially modified for accelerated setting, was comparable to that of type B with K2SO4 in both compressive and tensile strength (Table 1).

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Mosaic Mapping: A Means of Tiling Images to Shorten Acquisition Speed for Lower - Magnification SEM Images and Wavelength Dispersive Spectrometers (WDS) X-Ray Maps

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100164659 ◽

1996 ◽

Vol 54 ◽

pp. 438-439

Author(s):

J.D. Geller ◽

C.R. Herrington

Keyword(s):

Limiting Factors ◽

X Rays ◽

Angular Range ◽

Acceptance Angle ◽

Sem Images ◽

Worst Case ◽

X Ray ◽

Focusing Distance ◽

Layered Crystals ◽

Working Distance

The minimum magnification for which an image can be acquired is determined by the design and implementation of the electron optical column and the scanning and display electronics. It is also a function of the working distance and, possibly, the accelerating voltage. For secondary and backscattered electron images there are usually no other limiting factors. However, for x-ray maps there are further considerations. The energy-dispersive x-ray spectrometers (EDS) have a much larger solid angle of detection that for WDS. They also do not suffer from Bragg’s Law focusing effects which limit the angular range and focusing distance from the diffracting crystal. In practical terms EDS maps can be acquired at the lowest magnification of the SEM, assuming the collimator does not cutoff the x-ray signal. For WDS the focusing properties of the crystal limits the angular range of acceptance of the incident x-radiation. The range is dependent upon the 2d spacing of the crystal, with the acceptance angle increasing with 2d spacing. The natural line width of the x-ray also plays a role. For the metal layered crystals used to diffract soft x-rays, such as Be - O, the minimum magnification is approximately 100X. In the worst case, for the LEF crystal which diffracts Ti - Zn, ˜1000X is the minimum.

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Epidemics and population trends

Medicine and Power in Tunisia, 1780–1900 ◽

10.1017/cbo9780511523984.010 ◽

1983 ◽

pp. 107-113

Keyword(s):

Population Trends

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Hierarchical habitat selection by woodland caribou: its relationship to limiting factors

Ecography ◽

10.1034/j.1600-0587.2000.230409.x ◽

2000 ◽

Vol 23 (4) ◽

pp. 466-478 ◽

Cited By ~ 66

Author(s):

W. James Rettie ◽

Francois Messier

Keyword(s):

Habitat Selection ◽

Limiting Factors ◽

Woodland Caribou

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PERSPECTIVE DEVELOPMENT OF WORLD PRODUCTION OF FEEDS FOR AQUACULTURE: ALTERNATIVE SOURCES OF RAW MATERIALS

VESTNIK OF ASTRAKHAN STATE TECHNICAL UNIVERSITY SERIES FISHING INDUSTRY ◽

10.24143/2073-5529-2017-1-67-78 ◽

2017 ◽

pp. 67-78

Author(s):

Lina Yurievna Lagutkina

Keyword(s):

Raw Materials ◽

Limiting Factors ◽

Current Status ◽

Feed Production ◽

The World ◽

Market Trends ◽

Alternative Sources ◽

World Industry ◽

First Time ◽

A Current

The author of the article discloses the prospects of development of the world feed production for aquaculture based on the analysis of key innovative technological and market trends. The author specifies that shortage, high cost, low ecological compatibility of traditional raw materials - fish flour - are among major limiting factors in the development of production of feeds for aquaculture. This fact, in turn, limits sustainable development of aquaculture both in Russia, and in the world in general. The article presents the overview of a current status of the world industry of feed production in aquaculture, where the regional situation is studied, as well. For the first time, there is given the outlook of innovative technologies in feed production based on the alternative sources of protein (on the example of projects of leading aquabiotechnological companies) which will determine industry’s objectives for the mid-term perspective.

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Селекция и семеноводство картофеля в Камчатском крае

Kartofel` i ovoshi ◽

10.25630/pav.2018.8.18314 ◽

2018 ◽

Author(s):

N.I. Ryakhovskaya ◽

T.P. Sherstyukova ◽

M.L. Gamolina

Keyword(s):

Russian Federation ◽

Potato Yield ◽

The State ◽

Limiting Factors ◽

State Register ◽

Region Selection ◽

New Varieties ◽

The Russian Federation ◽

Selection Of

Рассмотрены агроклиматические условия Камчатского края и лимитирующие факторы, сдерживающие рост урожайности картофеля. Приведены характеристики новых сортов картофеля селекции Камчатского НИИСХ созданных в соответствии с приоритетными для региона направлениями селекции, включенных в Государственный реестр селекционных достижений РФ и охраняемых патентами.Agroclimatic conditions of the Kamchatka Krai and limiting factors that restrain the growth of potato yield are considered. The characteristics of new varieties of potatoes of the selection of the Kamchatsky RIA are created in accordance with the priority for the region selection areas included in the State Register of Selection Achievements of the Russian Federation and protected by patents.

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Assessment of reproductive capacity of representatives of ancestral complexes and especially their selection of seed in dry conditions

World Ecology Journal ◽

10.25726/nm.2019.66.65.001 ◽

2019 ◽

pp. 1-23

Author(s):

А.В. Семенютина ◽

С.Е. Лазарев ◽

К.А. Мельник

Keyword(s):

Weather Conditions ◽

Reproductive Capacity ◽

Limiting Factors ◽

Scientific Center ◽

Gleditsia Triacanthos ◽

Biological Potential ◽

Forest Reclamation ◽

Dry Conditions ◽

Generative Phase ◽

Selection Of

Представители родовых комплексов Robinia (Робиния), Gleditsia (Гледичия) относятся к экономически важным и перспективным, для деградированных ландшафтов засушливого региона, видам растений. Несмотря на это до последнего времени отсутствуют сведения по многим видам этих родовых комплексов, связанные с вопросами экологических основ семеноведения и их репродуктивной способности в условиях светлокаштановых почв Волгоградской области. Все это направлено на выявление и расширение перспективных ареалов культивирования для лесомелиорации и озеленения населенных пунктов. Цель исследований изучение репродуктивной способности представителей родовых комплексов Robinia (Робиния), Gleditsia (Гледичия) в коллекциях ФНЦ агроэкологии РАН и выявление особенностей их селекционного семеноведения для лесомелиорации и озеленения населенных пунктов в сухостепных условиях. Объектами исследований являлись виды и формы рода Robinia: R. viscosa Vent. R. neomexicana Gray. R. pseudoacacia L. R. neomexicana х pseudoacacia, и Gleditsia (G. triacanthos L., G. triacanthos L. f. inermis, G. caspica Desf, G. texana Sarg., G. aquatica, G. japonica, G. caspica, G. sinensis), произрастающие в кластерных участках коллекций ФНЦ агроэкологии РАН, кадастр 34:34:000000:122, 34:34:060061:10. Разработка основ селекционного семеноведения базируется на изучении репродуктивных особенностей выделенных для целевого использования собственных биоресурсов с учетом возможностей всестороннего изучения генеративных качеств и оценки биологического потенциала. Выявлено, что стабильность плодоношения фиксируется через несколько лет после вступления в генеративную фазу: у Robinia и Gleditsia 67 лет. Первое цветение у Gleditsia triacanthos и G. texana, G. aquatica наблюдалось в возрасте 5 лет, G. japonica 6, G. caspica и G. sinensis 8 лет. Завязываемость плодов зависит не только от возраста растения, но и от погодных условий во время цветения. На семенную продуктивность влияет количество выпавших осадков и сумма активных температур в период созревания плодов. Формирование более крупных плодов и семян наблюдается в возрасте до 15 лет. В результате исследований (20172019 гг.) выявлено влияние лимитирующих факторов на биологический потенциал цветения, плодоношения и семенную продуктивность для определения ареалов их культивирования. Representatives of generic systems Robinia, Gleditsia are economically important and promising for degraded arid landscapes of the region, types of plants. Despite this, until recently, there is no information on many types of these generic complexes related to the environmental foundations of seed and their reproductive capacity in light chestnut soils of the Volgograd region. All this is aimed at identifying and expanding promising areas of cultivation for forest reclamation and greening of settlements. The aim of the research is to study the reproductive capacity of representatives of ancestral complexes Robinia, Gleditsia in the collections of the Federal scientific center for Agroecology Russian Academy of Sciences and the identifying features of their selection of seed for forest reclamation and landscaping of settlements in the dry steppe conditions. The objects of research were species and forms of the genus Robinia: R. viscosa Vent. R. neomexicana Gray. R. pseudoacacia L. R. neomexicana x pseudoacacia and Gleditsia (G. triacanthos L., G. triacanthos L. f. inermis, G. caspica Desf, G. texana Sarg., G. aquatica, G. japonica, G. caspica, G. sinensis), growing in the cluster areas of collections of FSC Agroecology RAS, cadastre 34:34:000000:122, 34:34:060061:10. The development of the principles of seed breeding is based on the study of reproductive characteristics of the allocated for the targeted use of their own bioresources, taking into account the possibilities of a comprehensive study of generative qualities and assessment of biological potential. It was found that the stability of fruiting is fixed a few years after entering the generative phase: Robinia and Gleditsia 67 years. The first flowering in Gleditsia triacanthos and G. texana, G. aquatica was observed at the age of 5 years, G. japonica 6, G. caspica and G. sinensis 8 years. Fruit setability depends not only on the age of the plant, but also on weather conditions during flowering. Seed productivity is affected by the amount of precipitation and the amount of active temperatures during the ripening period. The formation of larger fruits and seeds is observed in the age of 15 years. As a result of studies (20172019), the influence of limiting factors on the biological potential of flowering, fruiting and seed production to determine the areas of their cultivation was revealed.

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