scholarly journals High-Efficiency Production of Radiopharmaceuticals via Droplet Radiochemistry: A Review of Recent Progress

2020 ◽  
Vol 19 ◽  
pp. 153601212097309
Author(s):  
Jia Wang ◽  
R. Michael van Dam
Keyword(s):  
High Efficiency ◽  
State Of The Art ◽  
System Size ◽  
Scaling Up ◽  
Activity Levels ◽  
Synthesis Time ◽  
Molar Activity ◽  
Reagent Consumption ◽  
Prosthetic Groups ◽  
Low Activity

New platforms are enabling radiochemistry to be carried out in tiny, microliter-scale volumes, and this capability has enormous benefits for the production of radiopharmaceuticals. These droplet-based technologies can achieve comparable or better yields compared to conventional methods, but with vastly reduced reagent consumption, shorter synthesis time, higher molar activity (even for low activity batches), faster purification, and ultra-compact system size. We review here the state of the art of this emerging direction, summarize the radiotracers and prosthetic groups that have been synthesized in droplet format, describe recent achievements in scaling up activity levels, and discuss advantages and limitations and the future outlook of these innovative devices.

scholarly journals Fast Accurate and Automatic Brushstroke Extraction

2021 ◽  
Vol 17 (2) ◽  
pp. 1-24
Author(s):  
Yunfei Fu ◽  
Hongchuan Yu ◽  
Chih-Kuo Yeh ◽  
Tong-Yee Lee ◽  
Jian J. Zhang
Keyword(s):  
Neural Network ◽  
Efficient Algorithm ◽  
Deep Neural Network ◽  
High Efficiency ◽  
State Of The Art ◽  
High Reliability ◽  
The Other ◽  
Manual Annotation ◽  
Stroke Extraction ◽  
Art Research

Brushstrokes are viewed as the artist’s “handwriting” in a painting. In many applications such as style learning and transfer, mimicking painting, and painting authentication, it is highly desired to quantitatively and accurately identify brushstroke characteristics from old masters’ pieces using computer programs. However, due to the nature of hundreds or thousands of intermingling brushstrokes in the painting, it still remains challenging. This article proposes an efficient algorithm for brush Stroke extraction based on a Deep neural network, i.e., DStroke. Compared to the state-of-the-art research, the main merit of the proposed DStroke is to automatically and rapidly extract brushstrokes from a painting without manual annotation, while accurately approximating the real brushstrokes with high reliability. Herein, recovering the faithful soft transitions between brushstrokes is often ignored by the other methods. In fact, the details of brushstrokes in a master piece of painting (e.g., shapes, colors, texture, overlaps) are highly desired by artists since they hold promise to enhance and extend the artists’ powers, just like microscopes extend biologists’ powers. To demonstrate the high efficiency of the proposed DStroke, we perform it on a set of real scans of paintings and a set of synthetic paintings, respectively. Experiments show that the proposed DStroke is noticeably faster and more accurate at identifying and extracting brushstrokes, outperforming the other methods.

Rapid one-step scalable microwave synthesis of Ti3C2Tx MXene

2021 ◽  
Author(s):  
Jing Zhu ◽  
Jingyi Zhang ◽  
Ruiming Lin ◽  
Benwei Fu ◽  
Chengyi Song ◽  
...  
Keyword(s):  
Microwave Heating ◽  
Microwave Synthesis ◽  
State Of The Art ◽  
Synthesis Time ◽  
One Step

We demonstrate a rapid one-step scalable microwave heating-based method to prepare Ti3C2Tx MXenes, which shortens the synthesis time from tens of hours from state-of-the-art approaches to 15 minutes and avoids...

scholarly journals An attemp to use a pulsed CO2 laser for decontamination of radioactive metal surfaces

2000 ◽  
Vol 65 (5-6) ◽  
pp. 445-450 ◽  
Author(s):  
Scepan Miljanic ◽  
Natasa Stjepanovic ◽  
Milan Trtica
Keyword(s):  
Stainless Steel ◽  
Co2 Laser ◽  
Metal Surfaces ◽  
High Efficiency ◽  
Germanium Detector ◽  
Surface Cleaning ◽  
Activity Levels ◽  
Air Atmosphere ◽  
Pulsed Co2 Laser ◽  
Pulse Energies

There is a growing interest in laser radioactive decontamination of metal surfaces. It offers advantages over conventional methods: improved safety, reduction of secondary waste, reduced waste volume, acceptable cost. The main mechanism of cleaning by lasers is ablation. Apulsed TEACO2 laser was used in this work for surface cleaning in order to show that ablation of metal surfaces is possible even at relatively low pulse energies, and to suggest that it could be competitive with other lasers because of much higher energy efficiencies. A brief theoretical analysis was made before the experiments. The laser beam was focused using a KBr-lens onto a surface contaminated with 137 Cs (b-, t1/2 = 30.17 y). Three different metals were used: stainless steel, copper and aluminium. The ablated material was pumped out in an air atmosphere and transferred to a filter. The presence of activity on the filter was shown by a germanium detector-multichannel analyzer. The activity levels were measured by a GM counter. The calculated decontamination factors and collection factors showed that ablation occurs with a relatively high efficiency of decontamination. This investigation suggests that decontamination using a CO2 laser should be seriously considered.

scholarly journals Scaling Up AND/OR Abstraction Sampling

2020 ◽  
Author(s):  
Kalev Kask ◽  
Bobak Pezeshki ◽  
Filjor Broka ◽  
Alexander Ihler ◽  
Rina Dechter
Keyword(s):  
Importance Sampling ◽  
State Of The Art ◽  
Empirical Evaluation ◽  
Search Space ◽  
Scaling Up ◽  
Sampling Scheme ◽  
Search Spaces

Abstraction Sampling (AS) is a recently introduced enhancement of Importance Sampling that exploits stratification by using a notion of abstractions: groupings of similar nodes into abstract states. It was previously shown that AS performs particularly well when sampling over an AND/OR search space; however, existing schemes were limited to ``proper'' abstractions in order to ensure unbiasedness, severely hindering scalability. In this paper, we introduce AOAS, a new Abstraction Sampling scheme on AND/OR search spaces that allow more flexible use of abstractions by circumventing the properness requirement. We analyze the properties of this new algorithm and, in an extensive empirical evaluation on five benchmarks, over 480 problems, and comparing against other state of the art algorithms, illustrate AOAS's properties and show that it provides a far more powerful and competitive Abstraction Sampling framework.

scholarly journals The Mesozoic of the South Caspian oil and gas province, Southwestern Turkmenistan – prospects for gas and oil exploration

2021 ◽  
pp. 102-133
Author(s):  
V.N. Melikhov ◽  
N.A. Krylov ◽  
I.V. Shevchenko ◽  
V.L. Shuster
Keyword(s):  
Oil And Gas ◽  
High Efficiency ◽  
State Of The Art ◽  
Oil Field ◽  
Seismic Exploration ◽  
Oil Exploration ◽  
The South ◽  
Analytical Review ◽  
Drilling Operations ◽  
Low Efficiency

Regarding the South Caspian oil and gas province, it is concluded that the Pliocene productivity prevails in the western part of the province, and that the gas and oil prospects of the eastern land side in the Mesozoic are prioritized. A retrospective analytical review of geological and geophysical data and publications on the Mesozoic of Southwestern Turkmenistan was carried out, which showed the low efficiency of the performed seismic and drilling operations in the exploration and evaluation of very complex Mesozoic objects. A massive resumption of state-of-the-art seismic exploration and appraisal drilling in priority areas and facilities performed by leading Russian companies is proposed. For some areas, a new, increased estimate of the projected gas resources is given. An example of modern high-efficiency additional exploration of the East Cheleken, a small Pliocene gas and oil field, which turned this field into a large one in terms of reserves, is given.

scholarly journals Low-cost high-efficiency system for solar-driven conversion of CO2 to hydrocarbons

2019 ◽  
Vol 116 (20) ◽  
pp. 9735-9740 ◽  
Author(s):  
Tran Ngoc Huan ◽  
Daniel Alves Dalla Corte ◽  
Sarah Lamaison ◽  
Dilan Karapinar ◽  
Lukas Lutz ◽  
...  
Keyword(s):  
High Efficiency ◽  
Electrochemical Cell ◽  
State Of The Art ◽  
Low Cost ◽  
Photovoltaic Cells ◽  
Energy Losses ◽  
Earth Abundant ◽  
Set Up ◽  
System Coupling ◽  
Perovskite Photovoltaic

Conversion of carbon dioxide into hydrocarbons using solar energy is an attractive strategy for storing such a renewable source of energy into the form of chemical energy (a fuel). This can be achieved in a system coupling a photovoltaic (PV) cell to an electrochemical cell (EC) for CO2 reduction. To be beneficial and applicable, such a system should use low-cost and easily processable photovoltaic cells and display minimal energy losses associated with the catalysts at the anode and cathode and with the electrolyzer device. In this work, we have considered all of these parameters altogether to set up a reference PV–EC system for CO2 reduction to hydrocarbons. By using the same original and efficient Cu-based catalysts at both electrodes of the electrolyzer, and by minimizing all possible energy losses associated with the electrolyzer device, we have achieved CO2 reduction to ethylene and ethane with a 21% energy efficiency. Coupled with a state-of-the-art, low-cost perovskite photovoltaic minimodule, this system reaches a 2.3% solar-to-hydrocarbon efficiency, setting a benchmark for an inexpensive all–earth-abundant PV–EC system.

scholarly journals Ambulatory Physical Activity Performance in Youth With Cerebral Palsy and Youth Who Are Developing Typically

2007 ◽  
Vol 87 (3) ◽  
pp. 248-257 ◽  
Author(s):  
Kristie F Bjornson ◽  
Basia Belza ◽  
Deborah Kartin ◽  
Rebecca Logsdon ◽  
John F McLaughlin
Keyword(s):  
Cerebral Palsy ◽  
Activity Levels ◽  
Ambulatory Activity ◽  
Cross Sectional ◽  
Walking Activity ◽  
Activity Performance ◽  
Cross Sectional Design ◽  
Low Activity ◽  
Gmfcs Level ◽  
Daily Total

Background and Purpose Assessment of walking activity in youth with cerebral palsy (CP) has traditionally been “capacity-based.” The purpose of this study was to describe the day-to-day ambulatory activity “performance” of youth with CP compared with youth who were developing typically. Subjects Eighty-one youth with CP, aged 10 to 13 years, who were categorized as being in Gross Motor Function Classification System (GMFCS) levels I to III and 30 age-matched youth who were developing typically were recruited. Methods Using a cross-sectional design, participants wore the StepWatch monitor for 7 days while documenting average daily total step counts, percentage of time they were active, ratio of medium to low activity levels, and percentage of time at high activity levels. Results The youth with CP demonstrated significantly lower levels of all outcomes than the comparison group. Discussion and Conclusion Daily walking activity and variability decreased as functional walking level (GMFCS level) decreased. Ambulatory activity performance within the context of the daily life for youth with CP appears valid and feasible as an outcome for mobility interventions in CP.

scholarly journals Fluorine-18 Labeled Fluorofuranylnorprogesterone ([18F]FFNP) and Dihydrotestosterone ([18F]FDHT) Prepared by “Fluorination on Sep-Pak” Method

Molecules ◽  
2019 ◽  
Vol 24 (13) ◽  
pp. 2389 ◽  
Author(s):  
Falguni Basuli ◽  
Xiang Zhang ◽  
Burchelle Blackman ◽  
Margaret E. White ◽  
Elaine M. Jagoda ◽  
...  
Keyword(s):  
Androgen Receptors ◽  
Quantitative Measure ◽  
Emission Tomography ◽  
In Vitro Assays ◽  
Affinity Binding ◽  
Synthesis Time ◽  
High Affinity ◽  
Molar Activity ◽  
Positron Emission

To further explore the scope of our recently developed “fluorination on Sep-Pak” method, we prepared two well-known positron emission tomography (PET) tracers 21-[18F]fluoro-16α,17α-[(R)-(1′-α-furylmethylidene)dioxy]-19-norpregn-4-ene-3,20-dione furanyl norprogesterone ([18F]FFNP) and 16β-[18F]fluoro-5α-dihydrotestosterone ([18F]FDHT). Following the “fluorination on Sep-Pak” method, over 70% elution efficiency was observed with 3 mg of triflate precursor of [18F]FFNP. The overall yield of [18F]FFNP was 64–72% (decay corrected) in 40 min synthesis time with a molar activity of 37–81 GBq/µmol (1000–2200 Ci/mmol). Slightly lower elution efficiency (~55%) was observed with the triflate precursor of [18F]FDHT. Fluorine-18 labeling, reduction, and deprotection to prepare [18F]FDHT were performed on Sep-Pak cartridges (PS-HCO3 and Sep-Pak plus C-18). The overall yield of [18F]FDHT was 25–32% (decay corrected) in 70 min. The molar activity determined by using mass spectrometry was 63–148 GBq/µmol (1700–4000 Ci/mmol). Applying this quantitative measure of molar activity to in vitro assays [18F]FDHT exhibited high-affinity binding to androgen receptors (Kd~2.5 nM) providing biological validation of this method.

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