Dependence of total dose response of bipolar linear microcircuits on applied dose rate

1994 ◽  
Vol 41 (6) ◽  
pp. 2544-2549 ◽  
Author(s):  
S. McClure ◽  
R.L. Pease ◽  
W. Will ◽  
G. Perry
Keyword(s):  
Total Dose ◽  
Dose Rate ◽  
Dose Response ◽  
Applied Dose

Dose rate and annealing effects on total dose response of MOS and bipolar circuits

1995 ◽  
Vol 42 (6) ◽  
pp. 1567-1574 ◽  
Author(s):  
T. Carriere ◽  
J. Beaucour ◽  
A. Gach ◽  
B. Johlander ◽  
L. Adams
Keyword(s):  
Total Dose ◽  
Dose Rate ◽  
Dose Response ◽  
Annealing Effects

Neutron and gamma ray total dose rate determination using anisn

1994 ◽  
Vol 44 (1-2) ◽  
pp. 119-123 ◽  
Author(s):  
E. Amin ◽  
N. Ashoub ◽  
A. Elkady
Keyword(s):  
Total Dose ◽  
Dose Rate ◽  
Gamma Ray

Cholangiocarcinoma: The impact of endobiliary high-dose-rate (HDR) brachytherapy dose response on survival

Brachytherapy ◽  
2006 ◽  
Vol 5 (2) ◽  
pp. 91
Author(s):  
Matthew Biagioli ◽  
B-Chen Wen ◽  
Brandon Patton ◽  
Caroline Hoffman ◽  
Mark Harvey
Keyword(s):  
Dose Rate ◽  
Dose Response ◽  
High Dose Rate ◽  
High Dose ◽  
Hdr Brachytherapy ◽  
The Impact

Kinetics of DNA Repair Under Chronic Irradiation at Low and Medium Dose Rates in Repair Proficient and Repair Compromised Normal Fibroblasts

2021 ◽  
Author(s):  
Elena K. Zaharieva ◽  
Megumi Sasatani ◽  
Kenji Kamiya
Keyword(s):  
Dna Damage ◽  
Dna Repair ◽  
Dose Rate ◽  
Dose Response ◽  
Chronic Irradiation ◽  
Dose Rates ◽  
Chronic Radiation ◽  
Damage Repair ◽  
Kinetics Of ◽  
Medium Dose

We present time and dose dependencies for the formation of 53BP1 and γH2AX DNA damage repair foci after chronic radiation exposure at dose rates of 140, 250 and 450 mGy/day from 3 to 96 h, in human and mouse repair proficient and ATM or DNA-PK deficient repair compromised cell models. We describe the time/dose-response curves using a mathematical equation which contains a linear component for the induction of DNA damage repair foci after irradiation, and an exponential component for their resolution. We show that under conditions of chronic irradiation at low and medium dose rates, the processes of DNA double-strand breaks (DSBs) induction and repair establish an equilibrium, which in repair proficient cells manifests as a plateau-shaped dose-response where the plateau is reached within the first 24 h postirradiation, and its height is proportionate to the radiation dose rate. In contrast, in repair compromised cells, where the rate of repair may be exceeded by the DSB induction rate, DNA damage accumulates with time of exposure and total absorbed dose. In addition, we discuss the biological meaning of the observed dependencies by presenting the frequency of micronuclei formation under the same irradiation conditions as a marker of radiation-induced genomic instability. We believe that the data and analysis presented here shed light on the kinetics of DNA repair under chronic radiation and are useful for future studies in the low-to-medium dose rate range.

Directional Dependence of Co-60 Irradiation on the Total Dose Response of Flash Memories

2019 ◽  
Vol 66 (1) ◽  
pp. 148-154
Author(s):  
Matthew J. Gadlage ◽  
David I. Bruce ◽  
James D. Ingalls ◽  
Dobrin P. Bossev ◽  
Matthew Mckinney ◽  
...  
Keyword(s):  
Total Dose ◽  
Dose Response ◽  
Flash Memories ◽  
Directional Dependence

scholarly journals Idiorrhythmic dose-rate variability in dietary zinc intake generates a different response pattern of zinc metabolism than conventional dose–response feeding

1997 ◽  
Vol 78 (1) ◽  
pp. 173-191 ◽  
Author(s):  
Berislav MomČilović ◽  
Philip G. Reeves ◽  
Michael J. Blake
Keyword(s):  
Dose Rate ◽  
Dose Response ◽  
Male Rats ◽  
Metabolic Efficiency ◽  
Zinc Metabolism ◽  
Deficient Diet ◽  
Zinc Intake ◽  
Conventional Dose ◽  
Zn Concentration ◽  
Different Response

We compared the effects of idiorrhythmic dose-rate feeding and conventional dose-response on the induction of intestinal metallothionein (IMT), expression of aortal heat-shock protein mRNA (HSP70mRNA) induced by restraint stress, and accumulation of Zn in the femur and incisor of young growing male rats. An idiorrhythmic approach requires that the average dietary Zn concentration (modulo, M) over the whole experiment (epoch, E) is kept constant across different groups. This is done by adjusting the Zn concentration of the supplemented diet supplied to compensate for the reduction in the number of days on which Zn-supplemented diet is fed, the latter being spread evenly over the experiment. Idiorrhythms involve offering the diet with n times theoverall Zn concentration (M) only every nth day with Zn-deficient diet offered on other days. Idiorrythmic Zn dose-rate feeding changed Zn accumulation in the femur and incisor in a complexbi-modal fashion, indicating that metabolic efficiency of dietary Zn is not constant but depends on Zn dose-rate. In contrast to feeding Zn in the conventional dose-response scheme, iMT and HSP7OmRNA were not affected by idiorrhythmic dose-rate feeding. Idiorrhythmic cycling in dietary Zn load posed no risk of a biochemical overload nor caused the animals to be stressed. Idiorrhythmic dose-rate feeding brings the dimension of time to the conventional dose-response

Intraventricular but not intraparaventricular nucleus metergoline elicits feeding in satiated rats

1994 ◽  
Vol 266 (5) ◽  
pp. R1562-R1567 ◽  
Author(s):  
D. V. Coscina ◽  
D. Feifel ◽  
J. N. Nobrega ◽  
P. J. Currie
Keyword(s):  
Locomotor Activity ◽  
Food Intake ◽  
Total Dose ◽  
Paraventricular Nucleus ◽  
Dose Response ◽  
Feeding Experiment ◽  
High Potency ◽  
Drug Doses ◽  
Dose Response Study ◽  
The Brain

Previous research has shown that systemic injections of the nonselective serotonin (5-HT) antagonist metergoline (MET) can stimulate feeding in both rats and humans. Five experiments were conducted to determine if this drug would elicit feeding in otherwise satiated rats after direct injections into the brain. In experiment 1, intraventricular infusions of 100 nmol MET produced reliable enhancements of feeding for 1 h compared with control infusions of a 5% tartaric acid (vehicle) solution. In experiment 2, a dose-response study of 0, 50, 100, and 150 nmol MET intraventricularly revealed that both 100 and 150 nmol doses reliably enhanced 1-h feeding, whereas 50 nmol did not. In experiment 3, tests of 90-min locomotor activity and water intake in the absence of food revealed that 100 nmol MET intraventricularly did not modify either behavior compared with vehicle infusions, suggesting a degree of feeding specificity to this effect. In an attempt to determine the site of intraventricular MET effects on feeding, experiment 4 tested 1-h feeding responses after 0, 5, 10, 20, 40, or 60 nmol MET were infused unilaterally into the paraventricular nucleus (PVN) of the hypothalamus. No reliable feeding was induced at any of these drug doses, although injections of 30 nmol norepinephrine (NE) were effective in doubling food intake. Experiment 5 further showed that bilateral infusions of 50 nmol MET in each PVN (total dose, 100 nmol) were ineffective in altering 1-h feeding. This contrasted markedly to the high potency of 15 nmol NE per site (total dose, 30 nmol), which elicited fivefold greater feeding than control infusions.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Syngeneic and allogeneic bone marrow engraftment after total body irradiation: dependence on dose, dose rate, and fractionation

Blood ◽  
1991 ◽  
Vol 77 (3) ◽  
pp. 661-669 ◽  
Author(s):  
JD Down ◽  
NJ Tarbell ◽  
HD Thames ◽  
PM Mauch
Keyword(s):  
Bone Marrow ◽  
Stem Cell ◽  
Radiation Dose ◽  
Dose Rate ◽  
Dose Response ◽  
Total Body Irradiation ◽  
Low Dose ◽  
Allogeneic Bone ◽  
Low Dose Rate ◽  
Total Body

Abstract Murine bone marrow chimera models were used to assess the efficacy of host total body irradiation (TBI) given at different doses, dose rates, and fractionation schemes in providing for engraftment of syngeneic and allogeneic bone marrow. B6-Hbbd congenic and LP mice, respectively, were used as donors (10(7) bone marrow cells) for syngeneic and allogenic (H-2 compatible) transplantation in standard B6 recipients. Stable marrow chimerism was determined from host and donor stem cell- derived hemoglobin phenotypes (Hbbs and Hbbd) on gel electrophoresis at 3 months posttransplant. Partial engraftment of syngeneic marrow was seen at single doses as low as 2 Gy, with the donor component increasing steadily with increasing TBI dose to a level of 100% at 7 Gy. Immunologic resistance of the host appeared to prevent allogeneic engraftment until 5.5 Gy. A very steep radiation dose response was then observed so that the level of chimerism with 6 Gy and above became comparable with syngeneic engraftment. Low dose rate (5 cGy minute-1) and fractionated TBI required higher total doses for equivalent engraftment (radiation dose-sparing) in both syngeneic and allogenic bone marrow transplantation. This displacement in the dose-response curve on fractionation was seen with interfraction intervals of 3 and 6 hours. A further dose-sparing effect was observed on extending the interval to 18 and 24 hours, but only for allogeneic transplantation, and may therefore be related to recovery of immune-mediated graft resistance. The involvement of multiple target cell populations in determining allogenic engraftment rendered the application of the linear-quadratic model for radiation cell survival problematic in this case. The recovery in dose when low dose rate and 6-hour interfraction intervals were applied in either syngeneic or allogeneic BMT is consistent with appreciable sub-lethal damage repair in the primitive self-renewing stem cell population of the host marrow. These results contrast with the poor repair capacity of the 11-day spleen colony- forming units (CFUs) population after fractionated irradiation and support the notion that ablation of early stem cells in the pre-CFUs compartment is essential for long-term marrow engraftment.

Assessment of gated sweep technique for total dose and dose rate analysis in bipolar oxides

2004 ◽  
Vol 51 (6) ◽  
pp. 3723-3729 ◽  
Author(s):  
E. Min ◽  
I. Sanchez ◽  
H.J. Barnaby ◽  
R.L. Pease ◽  
D.G. Platteter ◽  
...  
Keyword(s):  
Total Dose ◽  
Dose Rate ◽  
Rate Analysis

Evidence for dose and dose rate effects in human and animal radiation studies

2018 ◽  
Vol 47 (3-4) ◽  
pp. 97-112 ◽  
Author(s):  
M.P. Little
Keyword(s):  
Dose Rate ◽  
Dose Response ◽  
Low Dose ◽  
Atomic Bomb ◽  
Dose Range ◽  
Quadratic Model ◽  
Linear Quadratic ◽  
Dose Rates ◽  
Atomic Bomb Survivors ◽  
Linear Quadratic Model

For stochastic effects such as cancer, linear-quadratic models of dose are often used to extrapolate from the experience of the Japanese atomic bomb survivors to estimate risks from low doses and low dose rates. The low dose extrapolation factor (LDEF), which consists of the ratio of the low dose slope (as derived via fitting a linear-quadratic model) to the slope of the straight line fitted to a specific dose range, is used to derive the degree of overestimation (if LDEF > 1) or underestimation (if LDEF < 1) of low dose risk by linear extrapolation from effects at higher doses. Likewise, a dose rate extrapolation factor (DREF) can be defined, consisting of the ratio of the low dose slopes at high and low dose rates. This paper reviews a variety of human and animal data for cancer and non-cancer endpoints to assess evidence for curvature in the dose response (i.e. LDEF) and modifications of the dose response by dose rate (i.e. DREF). The JANUS mouse data imply that LDEF is approximately 0.2–0.8 and DREF is approximately 1.2–2.3 for many tumours following gamma exposure, with corresponding figures of approximately 0.1–0.9 and 0.0–0.2 following neutron exposure. This paper also cursorily reviews human data which allow direct estimates of low dose and low dose rate risk.

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