scholarly journals Blood, intestinal and skeletal calcium dynamics during egg formation

1993 ◽  
Vol 73 (3) ◽  
pp. 517-532 ◽  
Author(s):  
M. Clunies ◽  
R. J. Etches ◽  
C. Fair ◽  
S. Leeson
Keyword(s):  
Half Life ◽  
Ovulatory Cycle ◽  
Left Femur ◽  
Period 2 ◽  
Individual Cage ◽  
Brachial Vein ◽  
Ovulatory Period ◽  
Post Intubation ◽  
The Right ◽  
Over Time

An experiment was carried out to study the dynamics of various body-Ca pools in the hen during a single ovulatory cycle. One hundred 32-wk-old Single Comb White Leghorn hens were used. For experimental purposes the ovulatory cycle was divided into four periods: 1–6, 6–12, 12–18 and 18–24 h post-oviposition.At 0, 6, 12 and 18 h post-oviposition 25 hens each were intubated proventricularly with 15 μCi of 45Ca as CaCl2 solution. Approximately 1 mL of blood was collected from the leaf brachial vein, and the bird was subsequently placed in an individual cage. Red blood cells, labelled with 15Cr, were re-injected into the same bird from which it was collected. At 0.5, 1, 2, 4 and 6 h post-intubation with 45Ca, blood samples were taken from the right brachial vein of five hens and the birds were immediately killed, carcasses were dissected, the left femur and tibia-fibula were excised, and an egg, if present, was removed. Whole blood was assayed for 51Cr activity, and plasma, bones and shells were assayed for 45Ca activity and Ca concentration.Another five hens were injected in the right brachial vein with 15 μCi of 45Ca immediately following oviposition. Subsequently, the left brachial vein was catheterized and blood was sampled at 0.5, 1, 2, 4, 6, 12, 18 and 24 h post-injection.There were no significant (P > 0.05) differences in blood volume or plasma-Ca concentration for the four periods assayed. Following intubation, plasma-45Ca activity decreased quadratically (P < 0.05) with time for all four periods assayed. Regression analysis showed that the biological half-life of plasma 45Ca was 3.30, 2.13, 1.80 and 1.77 h for periods 1, 2, 3 and 4 respectively. When birds were injected intravenously with 45Ca the half-life of plasma 45Ca was 0.116 h.There were no significant (P > 0.05) changes over time in ash or Ca content of bone ends (BE) or medullary bone (MB). Only MB accumulated 45Ca during the first 6 h of the cycle. There was no difference (P > 0.05) in 45Ca activity of either BE or MB over time in period 2. Only BE experienced a significant (P < 0.05) loss in 45Ca during period 4.There were no differences (P > 0.05) in total shell ash. shell Ca or 45Ca with time in period 1. Shell ash increased (P < 0.05) by 188, 348 and 237 mg h−1 and shell Ca increased by 69, 128 and 82 mg h−1 in periods 2, 3 and 4, respectively. Accumulation of shell 45Ca confirmed that the transfer of Ca was greatest during period 4 of the ovulatory cycle. Using 45Ca dynamics, we estimated that over the entire ovulatory period 1716 mg of Ca was absorbed from the digestive tract and 1704 mg was secreted as shell. Key words: Calcium-45 activity, calcium-45 half-life; plasma 45Ca, bone 45Ca, shell 45Ca, shell secretion, Ca absorption

Improvement in prefrontal thalamic connectivity during the early course of the illness in recent-onset psychosis: a 12-month longitudinal follow-up resting-state fMRI study

2020 ◽  
pp. 1-9
Author(s):  
Daniel Bergé ◽  
Tyler A. Lesh ◽  
Jason Smucny ◽  
Cameron S. Carter
Keyword(s):  
Resting State ◽  
Resting State Fmri ◽  
Functional Changes ◽  
Recent Onset ◽  
Fmri Study ◽  
Clinical Meaning ◽  
Mixed Pattern ◽  
The Right ◽  
Over Time

Abstract Background Previous research in resting-state functional magnetic resonance imaging (rs-fMRI) has shown a mixed pattern of disrupted thalamocortical connectivity in psychosis. The clinical meaning of these findings and their stability over time remains unclear. We aimed to study thalamocortical connectivity longitudinally over a 1-year period in participants with recent-onset psychosis. Methods To this purpose, 129 individuals with recent-onset psychosis and 87 controls were clinically evaluated and scanned using rs-fMRI. Among them, 43 patients and 40 controls were re-scanned and re-evaluated 12 months later. Functional connectivity between the thalamus and the rest of the brain was calculated using a seed to voxel approach, and then compared between groups and correlated with clinical features cross-sectionally and longitudinally. Results At baseline, participants with recent-onset psychosis showed increased connectivity (compared to controls) between the thalamus and somatosensory and temporal regions (k = 653, T = 5.712), as well as decreased connectivity between the thalamus and left cerebellum and right prefrontal cortex (PFC; k = 201, T = −4.700). Longitudinal analyses revealed increased connectivity over time in recent-onset psychosis (relative to controls) in the right middle frontal gyrus. Conclusions Our results support the concept of abnormal thalamic connectivity as a core feature in psychosis. In agreement with a non-degenerative model of illness in which functional changes occur early in development and do not deteriorate over time, no evidence of progressive deterioration of connectivity during early psychosis was observed. Indeed, regionally increased connectivity between thalamus and PFC was observed.

scholarly journals Radiation-Induced Metabolic Shifts in the Hepatic Parenchyma: Findings from 18F-FDG PET Imaging and Tissue NMR Metabolomics in a Mouse Model for Hepatocellular Carcinoma

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2573
Author(s):  
Yi-Hsiu Chung ◽  
Cheng-Kun Tsai ◽  
Ching-Fang Yu ◽  
Wan-Ling Wang ◽  
Chung-Lin Yang ◽  
...  
Keyword(s):  
Fdg Pet ◽  
Liver Parenchyma ◽  
Metabolic Alterations ◽  
Nmr Metabolomics ◽  
Post Irradiation ◽  
The Third ◽  
Radiation Induced ◽  
18F Fdg ◽  
The Right ◽  
Over Time

Purpose: By taking advantage of 18F-FDG PET imaging and tissue nuclear magnetic resonance (NMR) metabolomics, we examined the dynamic metabolic alterations induced by liver irradiation in a mouse model for hepatocellular carcinoma (HCC). Methods: After orthotopic implantation with the mouse liver cancer BNL cells in the right hepatic lobe, animals were divided into two experimental groups. The first received irradiation (RT) at 15 Gy, while the second (no-RT) did not. Intergroup comparisons over time were performed, in terms of 18F-FDG PET findings, NMR metabolomics results, and the expression of genes involved in inflammation and glucose metabolism. Results: As of day one post-irradiation, mice in the RT group showed an increased 18F-FDG uptake in the right liver parenchyma compared with the no-RT group. However, the difference reached statistical significance only on the third post-irradiation day. NMR metabolomics revealed that glucose concentrations peaked on day one post-irradiation both, in the right and left lobes—the latter reflecting a bystander effect. Increased pyruvate and glutamate levels were also evident in the right liver on the third post-irradiation day. The expression levels of the glucose-6-phosphatase (G6PC) and fructose-1, 6-bisphosphatase 1 (FBP1) genes were down-regulated on the first and third post-irradiation days, respectively. Therefore, liver irradiation was associated with a metabolic shift from an impaired gluconeogenesis to an enhanced glycolysis from the first to the third post-irradiation day. Conclusion: Radiation-induced metabolic alterations in the liver parenchyma occur as early as the first post-irradiation day and show dynamic changes over time.

scholarly journals Zero Average Surface Controlled Boost-Flyback Converter

Energies ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 57
Author(s):  
Juan-Guillermo Muñoz ◽  
Fabiola Angulo ◽  
David Angulo-Garcia
Keyword(s):  
Duty Cycle ◽  
Period Doubling ◽  
Power Converter ◽  
Control Technique ◽  
Average Surface ◽  
Flyback Converter ◽  
Stable Period ◽  
Period 2 ◽  
Wide Range ◽  
The Right

The boost-flyback converter is a DC-DC step-up power converter with a wide range of technological applications. In this paper, we analyze the boost-flyback dynamics when controlled via a modified Zero-Average-Dynamics control technique, hereby named Zero-Average-Surface (ZAS). While using the ZAS strategy, it is possible to calculate the duty cycle at each PWM cycle that guarantees a desired stable period-1 solution, by forcing the system to evolve in such way that a function that is constructed with strategical combination of the states over the PWM period has a zero average. We show, by means of bifurcation diagrams, that the period-1 orbit coexists with a stable period-2 orbit with a saturated duty cycle. While using linear stability analysis, we demonstrate that the period-1 orbit is stable over a wide range of parameters and it loses stability at high gains and low loads via a period doubling bifurcation. Finally, we show that, under the right choice of parameters, the period-1 orbit controller with ZAS strategy satisfactorily rejects a wide range of disturbances.

Explaining the Epigraphic Habit in the Roman Empire: The Evidence of Epitaphs

1990 ◽  
Vol 80 ◽  
pp. 74-96 ◽  
Author(s):  
Elizabeth A. Meyer
Keyword(s):  
Roman Empire ◽  
North Africa ◽  
Legal Status ◽  
The Third ◽  
The Right ◽  
Political Economic ◽  
Over Time

It is now notorious that the production of inscriptions in the Roman Empire was not constant over time, but rose over the first and second centuries A.D. and fell in the third. Ramsay MacMullen pointed this out more than five years ago, with conclusions more cautionary than explanatory: ‘history is not being written in the right way’, he said, for historians have deduced Rome's decline from evidence that–since it appears only epigraphically–has merely disappeared for its own reasons, or have sought general explanations of decline in theories political, economic, or even demographic in nature, none of which can, in turn, explain the disappearance of epigraphy itself. Why this epigraphic habit rose and fell MacMullen left open to question, although he did postulate control by a ‘sense of audience’. The purpose of this paper is to propose that this ‘sense of audience’ was not generalized or generic, but depended on a belief in the value of romanization, of which (as noted but not explained by MacMullen's article) the epigraphic habit is also a rough indicator. Epitaphs constitute the bulk of all provincial inscriptions and in form and number are (generally speaking) the consequence of a provincial imitation of characteristically Roman practices, an imitation that depended on the belief that Roman legal status and style were important, and that may indeed have ultimately depended, at least in North Africa, on the acquisition or prior possession of that status. Such status-based motivations for erecting an epitaph help to explain not only the chronological distribution of epitaphs but also the differences in the type and distribution of epitaphs in the western and eastern halves of the empire. They will be used here moreover to suggest an explanation for the epigraphic habit as a whole.

scholarly journals Age-Related Effects on Right Femoral Bone of Male Wistar Rats: A Morphometric and Biomechanical Study

2021 ◽  
Author(s):  
Sheila Martins Puelker ◽  
Sonia Regina Ribeiro de Castro ◽  
Romeu Rodrigues de Souza ◽  
Laura Beatriz Mesiano Maifrino ◽  
Ricardo Aparecido Baptista Nucci ◽  
...  
Keyword(s):  
Cortical Thickness ◽  
Wistar Rats ◽  
Female Rats ◽  
Male Rats ◽  
Aged Rats ◽  
Femoral Bone ◽  
Middle Aged ◽  
Left Femur ◽  
Bone Stiffness ◽  
The Right

Abstract Introduction Study of the variations of bone characteristics with age in different animal models is important to design musculoskeletal studies. Thus, this study aimed to evaluate the bone mass, dimensions, and biomechanical parameters of the femur in young, middle-aged, and aged Wistar rats. Materials and Methods Thirty male rats (Rattus norvegicus) were divided in three groups (n = 10 per group)—3-month-old young rats, 12-month-old middle-aged rats, and 18-months-old aged rats. The right femurs were subjected sequentially to morphometric study (bone weight, cortical thickness) and biomechanical tests (maximum resistance strength and bone stiffness). Results We observed a significant increase in femur histological (cortical thickness) and biomechanical (maximum strength and bone stiffness) parameters with aging when compared with young animals. Conclusions With the advancing age, the right femoral bone of middle-aged and old animals had greater variations when compared with young animals. However, further studies with the aid of a comparison between right and left femur and other long bones in both male and female rats are needed to corroborate with our findings.

The right to the night sky in punitive enclosure context

2019 ◽  
Vol 15 (S367) ◽  
pp. 402-403
Author(s):  
Natalia Guevara ◽  
Rodrigo F. Haack ◽  
Victoria B. Acosta ◽  
María A. Senn ◽  
Carolina A. Silva ◽  
...  
Keyword(s):  
Social Work ◽  
Social Communication ◽  
Juvenile Detention ◽  
Educational Science ◽  
La Plata ◽  
Detention Centers ◽  
National University ◽  
Night Sky ◽  
The Right ◽  
Over Time

AbstractThe “Right to the night sky” outreach project holds astronomy workshops for children and teens deprived of their liberty in juvenile detention centers. It is carried out by an interdisciplinary group of students, graduates, and teachers of Astronomy, Geophysics, Educational Science, Law, Psychology, Social Work, and Social Communication. It’s has been accredited and recognized by the Faculty of Astronomical and Geophysical Sciences, and the National University of La Plata (Argentina) since the year 2014. This work presents the diverse activities developed in the project, the methodologies used, and an analysis of how the project evolved, grew, and expanded over time, continuing what has already been presented by Charalambous et al. (2014) and Haack et al. (2019)

Arguments used by proponents and opponents in Brazil’s regulatory discussions of e-cigarettes and heated tobacco products

2021 ◽  
pp. tobaccocontrol-2021-056628
Author(s):  
Mônica Nunes-Rubinstein ◽  
Teresa Leão
Keyword(s):  
Public Health ◽  
Content Analysis ◽  
Cigarette Smoking ◽  
Health Risks ◽  
Regulatory Agency ◽  
Economic Consequences ◽  
The Other ◽  
Tobacco Products ◽  
The Right ◽  
Over Time

ObjectivesTo identify proponents and opponents of the commercialisation and marketing of e-cigarettes and heated tobacco products (HTPs), identify the arguments used on both sides and compare how the arguments have changed over time, we analysed three policy discussions occurring in 2009, 2018 and 2019.MethodsWe conducted a content analysis of one document and six videos from these discussions, provided on the Brazilian Health Regulatory Agency website, or upon request.ResultsThe arguments most used by tobacco companies were related to claims that the use of e-cigarettes and HTPs is less harmful than conventional tobacco. Unions that support its commercialisation also argued that lifting the ban would prevent smuggling and guarantee their quality. On the other side, universities, medical and anti-tobacco institutions argued that such devices may have health risks, including the risk of inducing cigarette smoking. In 2009, most arguments belonged to the ‘health’ theme, while in 2018 and 2019 economic arguments and those related to morals and ethics were frequently used.ConclusionsThose that supported the commercialisation and marketing of e-cigarettes and HTPs first focused on arguments of harm reduction, while 10 years later the right to access and potential economic consequences also became common. Public health agents and academics must gather evidence to effectively respond to these arguments and discuss these policies, and must prepare themselves to use and respond to arguments related to moral and economic themes.

scholarly journals In vivo uptake of [14C]leucine by skeletal muscle ribosomes after injury in rats fed two levels of protein

1969 ◽  
Vol 23 (2) ◽  
pp. 271-280 ◽  
Author(s):  
V. R. Young ◽  
P. C. Huang
Keyword(s):  
Skeletal Muscle ◽  
Specific Activity ◽  
Male Rats ◽  
Thigh Muscle ◽  
Left Femur ◽  
The Right ◽  
And Control ◽  
The Relationship ◽  
In Vivo Uptake

1. After 14 days on a diet containing 5 or 25% casein male rats received a fracture of the left femur. Four hours before they were killed the injured and control rats were injected with [1-14C]leucine; the incorporation of radioactivity into an isolated fraction of skeletal muscle ribosomes was studied 6, 12, 24, 48, 72, 96 and 228 h after injury.2. The incorporation of [14C]leucine into the ribosome fraction in right thigh muscles dropped to 40% of control values 72 h after fracture in well-nourished rats and after 96 h with diets containing 5 or 25%, casein.3. The specific activity of the trichloroacetic acid-soluble fraction of muscle from injured rats was equal to or higher than that of the controls during the first 72 h but lower at 96 h.4. These results suggest that a reduced incorporation of amino acids by ribosomes from the right thigh muscle occurred on day 3 after fracture in the group receiving 25% casein but not in the group receiving 5% casein.5. Muscle RNA and DNA concentrations were not affected by the injury.6. The relationship between these findings and the loss of muscle N after injury is discussed.

scholarly journals Counseling over Time as a Correlate of Non-Urgent Undergraduate Institutional Commitment

2017 ◽  
Vol 7 (2) ◽  
pp. 96
Author(s):  
Gary Blau ◽  
John DiMino ◽  
Iris Abreu ◽  
Kayla LeLeux-LaBarge
Keyword(s):  
Mental Health ◽  
General Purpose ◽  
Institutional Commitment ◽  
University Counseling Center ◽  
University Counseling ◽  
Health Concerns ◽  
On Line ◽  
Mental Health Concerns ◽  
The Right ◽  
Over Time

The general purpose of this study was to examine counseling services as a correlate of institutional commitment and related variables over time on a sample of non-urgent undergraduates. Data for non-urgent clients at a University Counseling Center (UCC) were collected using on-line surveys over four time-periods. Within-time correlations generally showed that mental health concerns was negatively related to institutional commitment, while counseling help belief was positively related. Institutional commitment is defined as a student feeling that he or she selected the right institution to attend Using a smaller sample, i.e., n = 15, of complete-data clients matched-over-time, overall level of mental health concerns significantly declined, while institutional commitment significantly increased. Counseling help belief decreased from Time 1 to Time 2 but then increased over time. Scientifically demonstrating to higher-level University administration that counseling over time can positively influence undergraduates’ institutional commitment can help the UCC to increase its allocation of university-based resources to keep pace with non-urgent client demands.

scholarly journals The Right to Survival in the Democratic People's Republic of Korea

2010 ◽  
Vol 9 (1) ◽  
pp. 87-117 ◽  
Author(s):  
Jiyoung Song
Keyword(s):  
Human Rights ◽  
Cold War ◽  
Public Discourse ◽  
Confucian Tradition ◽  
The Public ◽  
The Past ◽  
North Korean Defectors ◽  
The Right ◽  
The Cold War ◽  
Over Time

AbstractFor the past decade, the author has examined North Korean primary public documents and concludes that there have been changes of identities and ideas in the public discourse of human rights in the DPRK: from strong post-colonialism to Marxism-Leninism, from there to the creation of Juche as the state ideology and finally 'our style' socialism. This paper explains the background to Kim Jong Il's 'our style' human rights in North Korea: his broader framework, 'our style' socialism, with its two supporting ideational mechanisms, named 'virtuous politics' and 'military-first politics'. It analyses how some of these characteristics have disappeared while others have been reinforced over time. Marxism has significantly withered away since the end of the Cold War, and communism was finally deleted from the latest 2009 amended Socialist Constitution, whereas the concept of sovereignty has been strengthened and the language of duties has been actively employed by the authority almost as a relapse to the feudal Confucian tradition. The paper also includes some first-hand accounts from North Korean defectors interviewed in South Korea in October–December 2008. They show the perception of ordinary North Koreans on the ideas of human rights.

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