scholarly journals The results of cryopreservation of bull sperm in vegetable fortifier using sorbent

2019 ◽  
pp. 81-84
Author(s):  
L. M. Pavlenko ◽  
B. T. Stegniy ◽  
T. B. Didyk ◽  
B. M. Pavlenko
Keyword(s):  
Silicon Dioxide ◽  
Artificial Insemination ◽  
Activated Charcoal ◽  
Cytoplasmic Membrane ◽  
Fertility Rate ◽  
High Dispersion ◽  
Gynecological Diseases ◽  
Bull Sperm

The paper presents results of the production and use of the phytofortificant of cytoplasmic sperm membranes based on legume hydrolysate with additional purification with sorbents for cryopreservation of bull sperm as an alternative to yolk diluents. The aim of the research was to achieve biosafety, that is, to avoid infectious gynecological diseases, agents of which can be transmitted by the yolk, to increase the fertility rate of females after artificial insemination and to create the conditions for the development of new long-term cryoprotective diluents. It has been established that legumes grain and their hydrolysates contain a toxic nickel element that adversely affects the cytoplasmic membrane of sperm. To reduce this influence, we conducted a study of the action of different sorbents. Activated charcoal standard, silicon dioxide and fine silica were used as sorbents. Sorbents were added in relation of 3% of the volume of medium. According to the results of the studies, the best results were in semen, diluted with medium using high-dispersion silicon dioxide

scholarly journals Fertility rate of short-term progestagen pretreated ewes in relation to breed: A field study

2018 ◽  
Vol 68 (1) ◽  
pp. 35
Author(s):  
S. PAPADOPOULOS ◽  
C. DELIGIANNIS ◽  
E. K. THEODOSIADOU ◽  
D. KANTAS ◽  
TH. LAINAS ◽  
...  
Keyword(s):  
Field Study ◽  
Artificial Insemination ◽  
Transition Period ◽  
Fertility Rate ◽  
Short Term ◽  
Serum Progesterone ◽  
Blood Samples ◽  
The Common ◽  
Natural Mating

The effect of short-term instead of long-term progestagen treatment on fertility of Karagouniko and Chios ewes, after natural mating or artificial insemination, was investigated. Two experiments were performed during the transition period from anοestrous to the breeding season. In the 1st experiment (natural mating, NM), Karagouniko and Chios ewes were randomly allocated into 3 groups, that were KLM (long-term progestagen treatment; n=35), KSM (short-term progestagen treatment; n=34), KSP (short-term progestagen treatment; prostaglandin; n=35) and CLM (n=40), CSM (n=35), CSP (n=38), respectively. In the 2nd experiment (intracervical artificial insemination, AI) Karagouniko and Chios ewes were randomly allocated into 3 groups, that were KLA (long-term progestagen treatment; AI at 54h; n=50), KSA1 (short-term progestagen treatment; AI at 54h; n=20), KSA2 (short-term progestagen treatment; AI at 48h; n=28) and CLA (n=40), CSA1 (n=16), CSA2 (n=20), respectively. At sponges’ removal (d0) all ewes received 400 IU eCG. Ten rams served NM, while for AI fresh diluted semen was used. Pregnancy diagnosis was performed, 45-50 days later. Ιn the 1st experiment, blood samples were collected, daily for 5 days, starting on d0, for serum progesterone assessment. Conception rate in Karagouniko ewes after NM was higher (P<0.05) in KSM (35.29%) compared to KLM (17.14%) group, but did not differ with KSP (28.57%) group, while after AI it was higher (P<0.05) in KLA (42.00%) or KSA1 (40.00%) compared to KSA2 (14.29%) group. In Chios ewes no significant differences were observed between groups either after NM [CLM (45.00%), CSM (36.84%), CSP (34.29%)] or after AI [CSA1 (50.00%), CSA2 (50.00%), CLA (45.00%)]. No significant differences were observed after NM or after AI in the litter size in both breeds. These results indicate that short-term progestagen treatment for oestrus synchronization could be applied in indigenous Greek sheep breeds, resulting in equal (Chios) or improved fertility (Karagouniko) than the common long-term one. Also, the fertility rate in ewes subjected to short-term progestagen treatment depends on the time of AI in relation to breed.

A New Look at the Asian Fertility Transition (Distinguishedl Lecture)

1996 ◽  
Vol 35 (4I) ◽  
pp. 385-398 ◽  
Author(s):  
John C. Caldwell
Keyword(s):  
Total Fertility Rate ◽  
Birth Rate ◽  
Fertility Transition ◽  
Fertility Rate ◽  
Asian Women ◽  
Population Replacement ◽  
Planning Meeting ◽  
Annual Birth Rate

The significance of the Asian fertility transition can hardly be overestimated. The relatively sanguine view of population growth expressed at the 1994 International Conference for Population and Development (ICPD) in Cairo was possible only because of the demographic events in Asia over the last 30 years. In 1965 Asian women were still bearing about six children. Even at current rates, today’s young women will give birth to half as many. This measure, namely the average number of live births over a reproductive lifetime, is called the total fertility rate. It has to be above 2— considerably above if mortality is still high—to achieve long-term population replacement. By 1995 East Asia, taken as a whole, exhibited a total fertility rate of 1.9. Elsewhere, Singapore was below long-term replacement, Thailand had just achieved it, and Sri Lanka was only a little above. The role of Asia in the global fertility transition is shown by estimates I made a few years ago for a World Bank Planning Meeting covering the first quarter of a century of the Asian transition [Caldwell (1993), p. 300]. Between 1965 and 1988 the world’s annual birth rate fell by 22 percent. In 1988 there would have been 40 million more births if there had been no decline from 1965 fertility levels. Of that total decline in the world’s births, almost 80 percent had been contributed by Asia, compared with only 10 percent by Latin America, nothing by Africa, and, unexpectedly, 10 percent by the high-income countries of the West. Indeed, 60 percent of the decline was produced by two countries, China and India, even though they constitute only 38 percent of the world’s population. They accounted, between them, for over threequarters of Asia’s fall in births.

scholarly journals Efficient Protocol for Improving the Development of Cryopreserved Embryonic Axes of Chestnut (Castanea sativa Mill.) by Encapsulation–Vitrification

Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 231
Author(s):  
Mariam Gaidamashvili ◽  
Eka Khurtsidze ◽  
Tamari Kutchava ◽  
Maurizio Lambardi ◽  
Carla Benelli
Keyword(s):  
Activated Charcoal ◽  
Castanea Sativa ◽  
Alginate Beads ◽  
Embryonic Axes ◽  
Root Regrowth ◽  
Castanea Sativa Mill ◽  
Whole Plants ◽  
Long Term Preservation ◽  
Direct Immersion

An optimized cryopreservation protocol for embryonic axes (EAs) of chestnut (Castanea sativa Mill.) has been developed based on the encapsulation–vitrification procedure. EAs of mature seeds were aseptically dissected and encapsulated in alginate beads with or without 0.3% (w/v) activated charcoal (AC). Embedded EAs were dehydrated with Plant Vitrification Solution 2 for different treatment times up to 120 min, followed by direct immersion in liquid nitrogen. Cryopreserved embryonic axes encapsulated with AC showed higher survival (70%) compared to those encapsulated without AC (50%). Sixty-four percent of embryonic axes, from synthetic seeds with AC, subsequently developed as whole plants. Plantlet regrowth was faster in AC-encapsulated EAs and showed enhanced postcryopreservation shoot and root regrowth over 2 cm after five weeks from rewarming. Results indicate that encapsulation–vitrification with activated charcoal added to the beads is an effective method for the long-term preservation of Castaneasativa embryonic axes.

scholarly journals Agglomeration economies, congestion diseconomies, and fertility dynamics in a two-region economy

2021 ◽  
Author(s):  
Madoka Muroishi ◽  
Akira Yakita
Keyword(s):  
Population Size ◽  
Stability Condition ◽  
Fertility Rate ◽  
Model Parameters ◽  
Initial Population ◽  
Interregional Migration ◽  
Stable Path ◽  
Regional Population ◽  
Initial Population Size

AbstractUsing a small, open, two-region economy model populated by two-period-lived overlapping generations, we analyze long-term agglomeration economy and congestion diseconomy effects of young worker concentration on migration and the overall fertility rate. When the migration-stability condition is satisfied, the distribution of young workers between regions is obtainable in each period for a predetermined population size. Results show that migration stability does not guarantee dynamic stability of the economy. The stationary population size stability depends on the model parameters and the initial population size. On a stable trajectory converging to the stationary equilibrium, the overall fertility rate might change non-monotonically with the population size of the economy because of interregional migration. In each period, interregional migration mitigates regional population changes caused by fertility differences on the stable path. Results show that the inter-regional migration-stability condition does not guarantee stability of the population dynamics of the economy.

Long-Term Hemoperfusion with Coated Activated Charcoal

1980 ◽  
Vol 17 (4) ◽  
pp. 543-546 ◽  
Author(s):  
Bashir Mamdani ◽  
George Dunea ◽  
Arnold W. Siemsen
Keyword(s):  
Activated Charcoal

scholarly journals Demographic forecasting of population projection in Greece: A Bayesian probabilistic study

2019 ◽  
Vol 29 (Supplement_4) ◽  
Author(s):  
D Lamnisos ◽  
K Giannakou ◽  
T Siligari
Keyword(s):  
Public Health ◽  
Life Expectancy ◽  
Total Fertility Rate ◽  
Total Population ◽  
Fertility Rate ◽  
Replacement Level ◽  
Demographic Aging ◽  
The Social ◽  
Support Ratio

Abstract Background Demographic aging is an emerging issue in Greece, characterized by low fertility and increased life expectancy. Undoubtedly, demographic aging is a challenge for public health not only due to the financing of public pensions, but also for the increasing utilization of health care. Methods The total fertility rate and life expectancy at birth are projected probabilistically using Bayesian hierarchical models and United Nations population data for Greece from the period of 1950 to 2015. These are then converted to age-specific mortality rates and combined with a cohort component projection model. This yields probabilistic projections of total population by sex and age groups, total fertility rate (TFR), female and male life expectancies at birth and potential support ratio PSR (persons aged 20-64 per person 65+) by the year 2100. Results The total population in Greece in 1950 was around 7.5 million, increasing to 11 million based on the 2011 population census but is projected to decline to 7.5 million at 2100. TFR has followed a strong downward trend with 1.4 children per woman in 2005-2010 and is projected to have a slight increase to 1.6 and 1.8 children per woman for 2050 and 2100 with all values being below the replacement-level fertility. Life expectancy is expected to increase to 84 years for men and 88 years for women in 2050, and 90 years for men and 94 years for women in 2100. PSR is expected to decline dramatically from 3 in 2011 to approximately 1.5 in 2050 and 2100. Conclusions Over the years, Greece has lost its youthful structure and has acquired the characteristics of an aging population, reflecting the population distribution of Western countries. Demographic aging is harmful for the economic growth, the social security system, the social assistance, and it is closely linked to national defense and public health. A long-term multidimensional program is recommended to confront the demographic issue based on the previous international experience. Key messages Total fertility rate will be below replacement level and potential support ratio will decline dramatically. A long-term multidimensional program needs to be developed to address the demographic aging.

scholarly journals Ubiquitous C IV 1550 Variability in B and Be Stars

1987 ◽  
Vol 92 ◽  
pp. 286-288 ◽  
Author(s):  
G. Sonneborn ◽  
M.P. Garhart ◽  
C.A. Grady
Keyword(s):  
Time Scale ◽  
High Dispersion ◽  
Be Stars ◽  
Line Profiles ◽  
Standard Star ◽  
B Stars ◽  
Short And Long Term ◽  
Resonance Transitions ◽  
Long Term Behavior

Studies of line profile variability of the ultraviolet 1550 Angstrom resonance transitions of C IV in Be stars (Sonneborn et al. 1986; Grady, et al. 1986a,b) have prompted an investigation into the short- and long-term behavior of the C IV lines in other types of B stars. We present examples of two well-studied Be stars, Omega Orionis and 66 Ophiuchi, and two non-Be stars, Beta Cephei and the standard star Zeta Cassiopeiae. Zeta Cas is also known to be a 53 Per variable (see Cox 1983). The IUE SWP high-dispersion spectra of Beta Cep and Zeta Cas have been obtained from the IUE archives. It has been known for some years that the C IV line profiles in Beta Cep vary in a time scale of several days (Fishel and Sparks, 1980). However, it came as a surprise to discover C IV variability in Zeta Cas. Available data allow us to set an upper limit of several months for the time scale of Zeta Cas C IV variability. The principal difference between the C IV variability in Be and non-Be stars appears to be the magnitude and velocity range of the effect.

scholarly journals Ernest John Christopher Polge. 16 August 1926 — 17 August 2006

2008 ◽  
Vol 54 ◽  
pp. 275-296
Author(s):  
R. H. F. Hunter
Keyword(s):  
Dairy Cattle ◽  
Artificial Insemination ◽  
Early Stage ◽  
Science And Technology ◽  
Biological Research ◽  
Biological Production ◽  
Mammalian Spermatozoa

Christopher Polge achieved distinction at a remarkably early stage of his career in biological research. He made key discoveries when he was in his twenties, and his work was internationally acclaimed when only just into his thirties. His name will always be associated with the deep–freeze preservation of mammalian spermatozoa and the massive boost that this gave to a fledgling artificial insemination industry,especially for the breeding of dairy cattle. Even so, his research contributions were wide–ranging, and their long–term influence onagriculture, medicine and biotechnology cannot be overestimated. Recognition came from many directions, perhaps most significantly as the recipient of the Japan Prize for Science and Technology for Biological Production in 1992.

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