peak concentration
Recently Published Documents


TOTAL DOCUMENTS

247
(FIVE YEARS 43)

H-INDEX

39
(FIVE YEARS 1)

Author(s):  
Mukesh Pratap Singh ◽  
Mohd Amir

Abstract We have investigated the effect of emitter design key parameters such as depth factor and the peak concentration for different types of emitter diffusion profiles (uniform, exponential, Gaussian, and Erfc) on the performance of silicon (Si) solar cells. The value of the depth factor is optimized as 0.1 µm for all these emitter diffusion profiles. Afterward, the peak concentration value is optimized for all the diffusion profiles. A close examination of relative diffusion lengths, conductivities, recombination rates, internal and external quantum efficiencies for these diffusion profiles revealed that among all the considered emitter diffusion profiles, the Erfc profile exhibits the maximum efficiency of 23.53% with an optimized peak concentration of 2×1020 cm-3 for emitter and 1×1019 cm-3 for the back surface filed doping. PC1D was used for all the simulations.


2021 ◽  
Author(s):  
Ronald B. Moss ◽  
Meghan McCabe Pryor ◽  
Rebecca Baillie ◽  
Katherine Kudrycki ◽  
Christina Friedrich ◽  
...  

Abstract Background: Previously, we reported on an opioid receptor quantitative systems pharmacology (QSP) model to evaluate naloxone dosing. Methods: In this study we extended our model to include higher systemic levels of fentanyl (up to 100 ng/ml) and the newly approved 8mg IN naloxone dose (equivalent to 4 mg)Results : As expected, at the lower peak fentanyl concentrations (25 ng/ml and 50 ng/ml), the simulations predicted that 2 mg, 4 mg, 5 mg, and 10 mg IM doses of naloxone displaced fentanyl and reached below the 50% receptor occupancy within 10 minutes. However, at the concentration of 75 ng/ml, the simulation predicted that the 2 mg dose of naloxone failed to reach below the 50% occupancy within 10 minutes. Interestingly, at the highest peak concentration of fentanyl studied (100 ng/ml), the model predicted that the 4 mg of naloxone IM (equivalent to 8 mg IN) failed to reach below the threshold of 50 % occupancy within 10 minutes or even within 15 minutes (Data not shown). In contrast, the model predicted successful reversals when 5 and 10 mg IM doses were utilized. Conclusion:These results support the notion that acutely administered higher doses of naloxone are needed for rapid and adequate clinical reversal, particularly when higher systemic exposure of the potent synthetic opioids occur.


2021 ◽  
Author(s):  
Gian Luca Salvagno ◽  
Brandon M. Henry ◽  
Laura Pighi ◽  
Simone De Nitto ◽  
Giuseppe Lippi

Abstract Background: Since serum anti-SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) IgA antibodies correlate with secretory anti-SARS-CoV-2 IgA and contribute to virus neutralization, we planned an observational study to measure serum anti-SARS-CoV-2 IgAs kinetics throughout a 6-month period in coronavirus disease 2019 (COVID-19) vaccine recipients.Methods: The study sample consisted of 97 baseline SARS-CoV-2 seronegative healthcare workers (median age 42 years and IQR 31-52 years; 52 females), who underwent vaccination with Pfizer/BioNTech Comirnaty mRNA-based vaccine (two 30 µg doses, 21 days apart). Serum samples were collected at baseline, before the second vaccine dose (i.e., day 21), and then 51, 111 and 201 days after enrolment (i.e., 1, 3 and 6 months after the second vaccine dose). Serum anti-SARS-CoV-2 spike S1 subunit IgA were measured with Anti-SARS-CoV-2 ELISA IgA (Euroimmun, Lübeck, Germany).Results: Anti-SARS-CoV-2 spike S1 subunit IgA displayed a peak at 1 month after the second vaccine dose, but then progressively waned afterwards. The 6-month serum anti-spike S1 subunit IgA concentration was 71% lower than the peak concentration. The rate of subjects with positive IgA values was 0% at baseline, 80.4% at day 21, 97.9% at day 51, but then declined to 73.2% and 53.6% at 3 and 6 months after the second vaccine dose. Serum anti-spike S1 subunit IgAs measured at 111 and 201 days was significantly lower than at the 51-day peak (both p<0.001). Significant inverse correlation was found between anti-SARS-CoV-2 IgA antibodies decline at 6 months/ and recipients’ age (r=-0.24; p=0.019).Conclusion: These findings may provide possible explanation to decreased efficacy of COVID-19 vaccines in preventing SARS-CoV-2 infection 6 months after vaccination.


2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 447-447
Author(s):  
Andrew P Foote ◽  
Abigail R Rathert ◽  
Carlee M Salisbury ◽  
Hunter L McConnell ◽  
David Lalman

Abstract Glucose and acetate are important nutrients for muscle and fat accretion in beef cattle. The objective of this experiment was to determine if the demand for acetate and glucose, as well as insulin response to glucose, are associated with dry matter intake (DMI), average daily gain (ADG), residual feed intake (RFI), and gain:feed (G:F). Charolais heifers (n = 16; initial BW = 412 ± 10 kg) were trained to close human contact and fed a finishing diet ad libitum in an Insentec feeding system. Following a 12-hour fast, a jugular catheter was inserted, and an acetate clearance test was performed by infusing acetate (2.18 mmol/kg BW0.75) and collecting blood samples over a 30-minute period. One hour after the conclusion of the acetate test, a glucose clearance test was performed by infusing glucose (7.57 mmol/kg BW0.75) and collecting samples over a two-hour period. Four days after the metabolic tests, heifers began an 84-d DMI and ADG test period. The area under the acetate, glucose, and insulin curves were calculated as were the clearance rate, peaks, nadir, and insulin time to peak. Pearson correlations were calculated for the metabolic parameters and production traits using SAS 9.4. Heifers gained 1.69 ± 0.03 kg/d and consumed 10.4 ± 0.19 kg/d. Acetate and glucose clearance rates were not associated with any production trait (P &gt; 0.40). Insulin time to peak concentration after the glucose challenge was associated (r = 0.69; P = 0.003) with G:F, but peak concentration was not (P = 0.45). Additionally, there was a trend (r = 0.40; P = 0.13) for area under the insulin curve to be associated with G:F. Given the small sample size in this experiment, it is possible that decreased insulin sensitivity early in the finishing period is related to improved feed efficiency in finishing heifers.


2021 ◽  
Author(s):  
Mark G. Papich ◽  
Roger J. Narayan

Abstract Naloxone and nalmefene were administered to seven research Beagle dogs, (mean weight approximately 12 kg) at a dose of 0.04 mg/kg and 0.014 mg/kg for naloxone and nalmefene, respectively. Each dose was administered intramuscularly (IM) with a standard IM injection and with a hollow microneedle device array using needles of 1 mm in length. The IM injection was delivered in the epaxial muscles, and the microneedle injection was delivered in the skin over the shoulder of each dog. Each dog received the same injections in a cross-over design. Following the injection, blood samples were collected for plasma analysis of naloxone and nalmefene by high pressure liquid chromatography with mass spectrometry detection (LCMS). The plasma sample concentrations were plotted for observed patterns of absorption and analyzed with non-compartmental pharmacokinetic methods (NCA). The results showed that the injection of naloxone from the microneedle device produced a higher peak concentration (CMAX) by 2.15x compared the IM injection of the same dose, and time to peak concentration (TMAX) was similar. For the nalmefene injection, the peak was not as high (lower CMAX) by 0.94x for the microneedle injection compared to the IM injection of the same dose. The microneedle produced an exposure, measured by area under the curve (AUC)) that was 0.85x and 0.58x as high for naloxone and nalmefene, respectively, than the injection by the IM route. We also observed that although the dose for naloxone was approximately 3x higher for naloxone compared to nalmefene, the mean peak concentration achieved from the naloxone injection was more than 12x higher than the nalmefene injection. These studies were designed to test the feasibility of using the hollow microneedle array as an effective method of naloxone and nalmefene delivery for emergency treatment of opioid-induced respiratory depression (OIRD). The results of these studies will form the basis of future studies, using the dog as a model, for development of hollow microneedle microarray devices to deliver opioid antagonists for treatment of OIRD in people.


2021 ◽  
Author(s):  
Rym Medjebeur Hanna ◽  
Michael Levy ◽  
Emmanuelle Bille ◽  
Carole Hennequin ◽  
Fabrice Lesage ◽  
...  

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. e15000-e15000
Author(s):  
Hongtao He ◽  
Lixing Wang ◽  
Guanglei Huang ◽  
Rongfeng Liu ◽  
Meng Yuan ◽  
...  

e15000 Background: To explore the correlation between plasma concentration of apatinib and clinical efficacy. Methods: 42 patients were enrolled. Plasma specimens of all patients were collected. At 7:40 am, fasting blood was drawn as plasma trough concentration (Ctrough). At 8 am, apatinib mesylate (APA-M, 250mg qd) was orally administrated. At 11 am, venous blood was drawn as plasma peak concentration (Cpeak). Each patient has Ctrough and Cpeak samples. A total of 84 plasma samples were obtained. The concentration of APA-M in plasma was determined by UPLC-MS/MS. Results: 1) 42 patients were evaluable. Treatment response was assessed by RECIST1.1. 2 patients achieved complete response (CR), 16 partial response (PR), 12 stable disease (SD) (tumor shrinks), 5 SD (tumor enlargement), 7 progressive disease (PD). Objective response rate (ORR) was 42.9% (18/42) and disease control rate (DCR) was 83.3% (35/42). 2) On day 1 and 456 after oral APA-M from different patients, median trough concentration (Ctrough median) was 264.38 ng/ml (1.18 ng/ml-918 ng/ml), and median peak concentration (Cpeak median) was 543.61 ng/ml (71.11 ng/ml-1609.4 ng/ml), respectively. 3) The Ctrough median in patients with CR, PR and SD (tumor shrinks) was significantly higher than that SD (tumor enlargement) and PD ( P<0.05). There was significantly difference between CR and PR with SD (tumor shrinks) ( P<0.05). But there was no significantly difference between CR and PR ( P>0.05). (Table) 4) The Cpeak median in patients with CR, PR, SD (tumor enlargement) and PD was significantly higher than that SD (tumor shrinks) ( P<0.05). But there was no significantly difference between CR and PR with SD (tumor enlargement) ( P>0.05). (Table). Conclusions: The plasma Ctrough of Apatinib can predict the clinical efficacy of patients with solid tumor. Perspective clinical studies with adequate sample size are required to validate our results. [Table: see text]


Marine Drugs ◽  
2021 ◽  
Vol 19 (4) ◽  
pp. 212
Author(s):  
Shuang Liu ◽  
Taocui Zhang ◽  
Huifang Sun ◽  
Lisha Lin ◽  
Na Gao ◽  
...  

dHG-5 (Mw 5.3 kD) is a depolymerized glycosaminoglycan from sea cucumber Holothuria fuscopunctata. As a selective inhibitor of intrinsic Xase (iXase), preclinical study showed it was a promising anticoagulant candidate without obvious bleeding risk. In this work, two bioanalytical methods based on the anti-iXase and activated partial thromboplastin time (APTT) prolongation activities were established and validated to determine dHG-5 concentrations in plasma and urine samples. After single subcutaneous administration of dHG-5 at 5, 9, and 16.2 mg/kg to rats, the time to peak concentration (Tmax) was at about 1 h, and the peak concentration (Cmax) was 2.70, 6.50, and 10.11 μg/mL, respectively. The plasma elimination half-life(T1/2β) was also about 1 h and dHG-5 could be almost completely absorbed after s.c. administration. Additionally, the pharmacodynamics of dHG-5 was positively correlated with its pharmacokinetics, as determined by rat plasma APTT and anti-iXase method, respectively. dHG-5 was mainly excreted by urine as the unchanged parent drug and about 60% was excreted within 48 h. The results suggested that dHG-5 could be almost completely absorbed after subcutaneous injection and the pharmacokinetics of dHG-5 are predictable. Studying pharmacokinetics of dHG-5 could provide valuable information for future clinical studies.


2021 ◽  
Vol 2021 ◽  
pp. 1-19
Author(s):  
Li Su ◽  
Ditao Niu ◽  
Daguan Huang ◽  
Qiang Fu

This study investigated the chloride transport performance of basalt-polypropylene fiber reinforced concrete (BPFRC) subjected to drying-wetting cycles. The effects of the strength grade, basalt fiber (BF), polypropylene fiber (PF), and hybrid BF-PF on the pore solution pH, chloride concentration distribution, chloride peak concentration (Cmax), and apparent chloride diffusion coefficient (Da) of the BPFRC were analyzed, and a multifactor model of Da was established. Moreover, the microstructures of BPFRC were studied to explore the effect of fibers on chloride transport performance of concrete in terms of theoretical pore volume, fiber-matrix interface, fiber bonding properties, and corrosion morphology. The results showed that the chloride concentration of the BPFRC increased and the pore solution pH of the BPFRC decreased with the increase in the exposure time. The chloride concentration and Da of the BPFRC decreased with the increase in the strength grade. At a fiber volume content of 0.1%, the addition of BF and PF reduced the chloride concentration and Da of the BPFRC; at a fiber volume content of 0.2%, the addition of hybrid BF-PF increased the chloride concentration and Da of the concrete. The chloride peak concentration appeared at the depth of 2 mm inside the concrete, and the change of the chloride peak concentration with exposure time followed the power function model. The theoretical pore volume of the BPFRC specimens decreased initially and then increased with the increase in the exposure time. FE-SEM observed that the bonding property between BF and matrix was better than that of PF, which could effectively control the development of microcracks.


Sign in / Sign up

Export Citation Format

Share Document