scholarly journals Microfluidic oxygen tolerability screening of nanocarriers for triplet fusion photon upconversion

2021 ◽  
Author(s):  
Jussi Isokuortti ◽  
Iiro Kiiski ◽  
Tiina Sikanen ◽  
Nikita Durandin ◽  
Timo Laaksonen
Keyword(s):  
High Energy ◽  
Full Potential ◽  
Microfluidic Chips ◽  
Ambient Conditions ◽  
Oxygen Scavengers ◽  
Energy Excitation ◽  
Oxygen Levels ◽  
Oxygen Scavenging ◽  
Oxygen Sensitive ◽  
The Mean

The full potential of triplet fusion photon upconversion (TF-UC) of providing high-energy photons locally with low-energy excitation is limited in biomedicine and life sciences by its oxygen sensitivity. This hampers the applicability of TF-UC systems in sensors, imaging, optogenetics and drug release. Despite the advances in improving the oxygen tolerability of TF-UC systems, the evaluation of oxygen tolerability is based on comparing the performance at completely deoxygenated (0 % oxygen) and ambient (20–21 %) conditions, leaving the physiological oxygen levels (0.3–13.5 %) neglected. This oversight is not deliberate and is only the result of the lack of simple and predictable methods to obtain and maintain these physiological oxygen levels in an optical setup. Herein, we demonstrate the use of microfluidic chips made of oxygen depleting materials to study the oxygen tolerability of four different micellar nanocarriers made of FDA-approved materials with various oxygen scavenging capabilities by screening their TF-UC performance over physiological oxygen levels. All nanocarriers were capable of efficient TF-UC even in ambient conditions. However, utilizing oxygen scavengers in the oil phase of the nanocarrier improves the oxygen tolerability considerably. For example, at the mean tumour oxygen level (1.4 %), nanocarriers made of surfactants and oil phase both capable of oxygen scavenging retained remarkably 80 % of their TF-UC emission. This microfluidic concept enables faster, simpler and more realistic evaluation of, not only TF-UC, but any micro or nanoscale oxygen-sensitive system and facilitates their development and implementation in biomedical and life science applications.

Anisotropy of damage productions in electron irradiated molybdenum

1978 ◽  
Vol 36 (1) ◽  
pp. 354-355
Author(s):  
K. Izui ◽  
S. Furuno ◽  
H. Otsu ◽  
T. Nishida ◽  
H. Maeta
Keyword(s):  
Electron Flux ◽  
Threshold Energy ◽  
High Energy ◽  
Voltage Electron ◽  
High Voltage Electron Microscope ◽  
Displacement Threshold ◽  
The Mean ◽  
Channeling Effect ◽  
Different Origins ◽  
Threshold Energies

Anisotropy of damage productions in crystals due to high energy electron bombardment are caused from two different origins. One is an anisotropic displacement threshold energy, and the other is an anisotropic distribution of electron flux near the atomic rows in crystals due to the electron channeling effect. By the n-beam dynamical calculations for germanium and molybdenum we have shown that electron flux at the atomic positions are from ∽4 to ∽7 times larger than the mean incident flux for the principal zone axis directions of incident 1 MeV electron beams, and concluded that such a locally increased electron flux results in an enhanced damage production. The present paper reports the experimental evidence for the enhanced damage production due to the locally increased electron flux and also the results of measurements of the displacement threshold energies for the <100>,<110> and <111> directions in molybdenum crystals by using a high voltage electron microscope.

scholarly journals The Surgical Outcomes of Unstable Ankle Fractures in Patients Aged >65 Years

2021 ◽  
Vol 12 ◽  
pp. 215145932199776
Author(s):  
Adem Sahin ◽  
Anıl Agar ◽  
Deniz Gulabi ◽  
Cemil Erturk
Keyword(s):  
Surgical Outcomes ◽  
External Rotation ◽  
High Energy ◽  
Ankle Fractures ◽  
Medial Malleolus ◽  
Aofas Score ◽  
Non Union ◽  
The Mean ◽  
Medial Malleolus Fracture ◽  
Mechanism Of Trauma

Aim: To evaluate the surgical outcomes and complications of patients over 65 years of age, with unstable ankle fractures. Material and Method: The study included 111 patients (73F/38 M) operated on between January 2015 and February 2019 and followed up for a mean of 21.2 months (range, 6-62 months).Demographic characteristics, comorbidities, fracture type, and mechanisms of injury were evaluated. Relationships between postoperative complications and comorbidities were examined. In the postoperative functional evaluations, the AOFAS score was used and pre and postoperative mobilization (eg, use of assistive devices) was assessed. Results: The mean age of the patients was 70.5 ± 6.1 years (range, 65-90 years). The mechanism of trauma was low-energy trauma in 90.1% of the fractures and high-energy trauma in 9.9%. The fractures were formed with a SER injury (supination external rotation) in 83.7% of cases and bimalleolar fractures were seen most frequently (85/111, 76%).Complications developed in 16 (14.4%) patients and a second operation was performed in 11 (9.9%) patients with complications. Plate was removed and debridement was performed in 5 of 6 patients due to wound problems. Nonunion was developed in the medial malleolus in 4 patients. Revision surgery was performed because of implant irritation in 2 patients and early fixation loss in the medial malleolus fracture in one patient. Calcaneotibial arthrodesis was performed in 3 patients because of implant failure and ankle luxation associated with non-union. A correlation was determined between ASA score and DM and complications, but not with osteoporosis. The mean follow-up AOFAS score was 86.7 ± 12.5 (range, 36-100).A total of 94 (84.7%) patients could walk without assistance postoperatively and 92 (82.9%) were able to regain the preoperative level of mobilization. Conclusion: Although surgery can be considered an appropriate treatment option for ankle fractures in patients aged >65 years, care must be taken to prevent potential complications and the necessary precautions must be taken against correctable comorbidities.

scholarly journals Importance of a Follow-Up Ultrasound Protocol in Monitoring Posttraumatic Spleen Complications in Children Treated with a Non-Operative Management

Medicina ◽  
2021 ◽  
Vol 57 (8) ◽  
pp. 734
Author(s):  
Ivona Djordjevic ◽  
Dragoljub Zivanovic ◽  
Ivana Budic ◽  
Ana Kostic ◽  
Danijela Djeric
Keyword(s):  
Splenic Abscess ◽  
Operative Management ◽  
High Energy ◽  
Significant Difference ◽  
Injury Grade ◽  
Grade Ii ◽  
The Mean ◽  
Non Operative Management ◽  
Grade Iii

Background and objectives: For the last three decades, non-operative management (NOM) has been the standard in the treatment of clinically stable patients with blunt spleen injury, with a success rate of up to 95%. However, there are no prospective issues in the literature dealing with the incidence and type of splenic complications after NOM. Materials and methods: This study analyzed 76 pediatric patients, up to the age of 18, with blunt splenic injury who were treated non-operatively. All patients were included in a posttraumatic follow-up protocol with ultrasound examinations 4 and 12 weeks after injury. Results: The mean age of the children was 9.58 ± 3.97 years (range 1.98 to 17.75 years), with no statistically significant difference between the genders. The severity of the injury was determined according to the American Association for Surgery of Trauma (AAST) classification: 7 patients had grade I injuries (89.21%), 21 patients had grade II injuries (27.63%), 33 patients had grade III injuries (43.42%), and 15 patients had grade IV injuries (19.73%). The majority of the injuries were so-called high-energy ones, which were recorded in 45 patients (59.21%). According to a previously created posttraumatic follow-up protocol, complications were detected in 16 patients (21.05%). Hematomas had the highest incidence and were detected in 11 patients (14.47%), while pseudocysts were detected in 3 (3.94%), and a splenic abscess and pseudoaneurysm were detected in 1 patient (1.31%), respectively. The complications were in a direct correlation with injury grade: seven occurred in patients with grade IV injuries (9.21%), five occurred in children with grade III injuries (6.57%), three occurred in patients with grade II injuries (3.94%), and one occurred in a patient with a grade I injury (1.31%). Conclusion: Based on the severity of the spleen injury, it is difficult to predict the further course of developing complications, but complications are more common in high-grade injuries. The implementation of a follow-up ultrasound protocol is mandatory in all patients with NOM of spleen injuries for the early detection of potentially dangerous and fatal complications.

scholarly journals Mechanosynthesis and Thermoelectric Properties of Fe, Zn, and Cd-Doped P-Type Tetrahedrite: Cu12-xMxSb4S13

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3448
Author(s):  
Francisco Arturo López Cota ◽  
José Alonso Díaz-Guillén ◽  
Oscar Juan Dura ◽  
Marco Antonio López de la Torre ◽  
Joelis Rodríguez-Hernández ◽  
...  
Keyword(s):  
Thermoelectric Properties ◽  
Figure Of Merit ◽  
Powder Processing ◽  
High Energy ◽  
Secondary Phases ◽  
Ambient Conditions ◽  
Cadmium Sulfate ◽  
Electrical Conductivities ◽  
Compositional Changes ◽  
P Type

This contribution deals with the mechanochemical synthesis, characterization, and thermoelectric properties of tetrahedrite-based materials, Cu12-xMxSb4S13 (M = Fe2+, Zn2+, Cd2+; x = 0, 1.5, 2). High-energy mechanical milling allows obtaining pristine and substituted tetrahedrites, after short milling under ambient conditions, of stoichiometric mixtures of the corresponding commercially available binary sulfides, i.e., Cu2S, CuS, Sb2S3, and MS (M = Fe2+, Zn2+, Cd2+). All the target materials but those containing Cd were obtained as single-phase products; some admixture of a hydrated cadmium sulfate was also identified by XRD as a by-product when synthesizing Cu10Cd2Sb4S13. The as-obtained products were thermally stable when firing in argon up to a temperature of 350–400 °C. Overall, the substitution of Cu(II) by Fe(II), Zn(II), or Cd(II) reduces tetrahedrites’ thermal and electrical conductivities but increases the Seebeck coefficient. Unfortunately, the values of the thermoelectric figure of merit obtained in this study are in general lower than those found in the literature for similar samples obtained by other powder processing methods; slight compositional changes, undetected secondary phases, and/or deficient sintering might account for some of these discrepancies.

scholarly journals Ultrafast charge transfer dynamics in 2D Covalent Organic Frameworks/Re-complex hybrid photocatalyst for CO2 reduction: hot electrons vs. cold electrons

2021 ◽  
Author(s):  
Qinying Pan ◽  
Mohamed Abdellah ◽  
Yuehan Cao ◽  
Yang Liu ◽  
Weihua Lin ◽  
...  
Keyword(s):  
Excited State ◽  
Charge Transfer ◽  
Excitation Energy ◽  
Co2 Reduction ◽  
Underlying Mechanism ◽  
High Energy ◽  
Hot Electrons ◽  
Covalent Organic Frameworks ◽  
Energy Excitation ◽  
Energy Dependent

Abstract Rhenium(I)-carbonyl-diimine complexes are promising photocatalysts for CO2 reduction. Covalent organic frameworks (COFs) can be perfect sensitizers to enhance the reduction activities. Here we investigated the excited state dynamics of COF (TpBpy) with 2,2'-bipyridine incorporating Re(CO)5Cl (Re-TpBpy) to rationalize the underlying mechanism. The time-dependent DFT calculation first clarified excited state structure of the hybrid catalyst. The studies from transient visible and infrared spectroscopies revealed the excitation energy-dependent photo-induced charge transfer pathways in Re-TpBpy. Under low energy excitation, the electrons at the LUMO level are quickly injected from Bpy into ReI center (1–2 ps) followed by backward recombination (13 ps). Under high energy excitation, the hot-electrons are first injected into the higher unoccupied level of ReI center (1–2 ps) and then slowly relax back to the HOMO in COF (24 ps). There also remains long-lived free electrons in the COF moiety. This explained the excitation energy-dependent CO2 reduction performance in our system.

scholarly journals Metal-Water mixtures for Propulsion and Energy-Conversion Applications: Recent Progress and Future Directions

2018 ◽  
Vol 20 (1) ◽  
pp. 53 ◽  
Author(s):  
Dilip Sundaram
Keyword(s):  
Particle Size ◽  
Energy Conversion ◽  
Experimental Studies ◽  
High Energy ◽  
High Energy Density ◽  
Full Potential ◽  
Predictive Tool ◽  
Practical Applications ◽  
Relative Safety ◽  
Metal Water

The metal-water system is attractive for propulsion and energy-conversion applications. Of all metals, aluminum is attractive due to its high energy density, relative safety, and low cost. Experimental studies provide new insight on the combustion and propulsive behaviors. The burning rate is found to be a strong function of both pressure and particle size. Furthermore, there is a wide scatter in the measured pressure exponents due to differences in particle size, pressure, pH, and equivalence ratio. A major problem with Al/H2O mixtures is incomplete combustion and poor impulses, thereby rendering Al/H2O mixtures unsuitable for practical applications. Efforts to improve the performance of Al/H2O mixtures have only met with moderate success. Although experiments have revealed these new trends, not much is offered in terms of the underlying physics and mechanisms. To explore the combustion mechanisms, theoretical models based on energy balance analysis have been developed. These models involve numerous assumptions and many complexities were either ignored or treated simplistically. The model also relies on empirical inputs, which makes it more a useful guide than a predictive tool. Future works must endeavor to conduct a more rigorous analysis of metal-water combustion. Empirical inputs should be avoided and complexities must be properly treated to capture the essential physics of the problem. The model should help us properly understand the experimental trends, offer realistic predictions for unexplored conditions, and suggest guidelines and solutions in order to realize the full potential of metal-water mixtures.

scholarly journals Regulation of murine myocardial energy metabolism during adrenergic stress studied by in vivo 31P NMR spectroscopy

2003 ◽  
Vol 285 (5) ◽  
pp. H1976-H1979 ◽  
Author(s):  
A. V. Naumova ◽  
R. G. Weiss ◽  
V. P. Chacko
Keyword(s):  
Heart Rate ◽  
Cardiac Metabolism ◽  
High Energy ◽  
Dobutamine Stress ◽  
Resonance Spectroscopy ◽  
31P Nmr Spectroscopy ◽  
Adult Mice ◽  
The Mean ◽  
Large Animals

Image-guided, spatially localized 31P magnetic resonance spectroscopy (MRS) was used to study in vivo murine cardiac metabolism under resting and dobutamine-induced stress conditions. Intravenous dobutamine infusion (24 μg · min–1 · kg body wt–1) increased the mean heart rate by ∼39% from 482 ± 46 per min at baseline to 669 ± 77 per min in adult mice. The myocardial phosphocreatine (PCr)-to-ATP (PCr/ATP) ratio remained unchanged at 2.1 ± 0.5 during dobutamine stress, compared with baseline conditions. Therefore, we conclude that a significant increase in heart rate does not result in a decline in the in vivo murine cardiac PCr/ATP ratio. These observations in very small mammals, viz., mice, at extremely high heart rates are consistent with studies in large animals demonstrating that global levels of high-energy phosphate metabolites do not regulate in vivo myocardial metabolism during physiologically relevant increases in cardiac work.

scholarly journals Accurate Prediction of Band Structure of FeS2: A Hard Quest of Advanced First-Principles Approaches

2021 ◽  
Vol 9 ◽  
Author(s):  
Min-Ye Zhang ◽  
Hong Jiang
Keyword(s):  
Band Structure ◽  
First Principles ◽  
High Energy ◽  
Accurate Prediction ◽  
Band Gaps ◽  
Full Potential ◽  
Band Structures ◽  
Electronic Band ◽  
Fundamental Band ◽  
Hybrid Functionals

The pyrite and marcasite polymorphs of FeS2 have attracted considerable interests for their potential applications in optoelectronic devices because of their appropriate electronic and optical properties. Controversies regarding their fundamental band gaps remain in both experimental and theoretical materials research of FeS2. In this work, we present a systematic theoretical investigation into the electronic band structures of the two polymorphs by using many-body perturbation theory with the GW approximation implemented in the full-potential linearized augmented plane waves (FP-LAPW) framework. By comparing the quasi-particle (QP) band structures computed with the conventional LAPW basis and the one extended by high-energy local orbitals (HLOs), denoted as LAPW + HLOs, we find that one-shot or partially self-consistent GW (G0W0 and GW0, respectively) on top of the Perdew-Burke-Ernzerhof (PBE) generalized gradient approximation with a converged LAPW + HLOs basis is able to remedy the artifact reported in the previous GW calculations, and leads to overall good agreement with experiment for the fundamental band gaps of the two polymorphs. Density of states calculated from G0W0@PBE with the converged LAPW + HLOs basis agrees well with the energy distribution curves from photo-electron spectroscopy for pyrite. We have also investigated the performances of several hybrid functionals, which were previously shown to be able to predict band gaps of many insulating systems with accuracy close or comparable to GW. It is shown that the hybrid functionals considered in general fail badly to describe the band structures of FeS2 polymorphs. This work indicates that accurate prediction of electronic band structure of FeS2 poses a stringent test on state-of-the-art first-principles approaches, and the G0W0 method based on semi-local approximation performs well for this difficult system if it is practiced with well-converged numerical accuracy.

Based on Comparable Price Energy Input-Output Table of Xinjiang to Research Low Carbon Economic Development Strategy

2013 ◽  
Vol 291-294 ◽  
pp. 1573-1576
Author(s):  
Yuan Sheng Huang ◽  
Lu Tong Li
Keyword(s):  
Development Strategy ◽  
Carbon Emissions ◽  
Energy Input ◽  
High Energy ◽  
Low Carbon ◽  
Input Output ◽  
Output Table ◽  
The Mean ◽  
The Cost ◽  
Advanced Production

Based on the input-output theory, the paper using the comparable price energy input-output table,quantitatively estimates the implicit carbon emissions of each industrial department,and analyzes the growth of the implicit carbon emissions of the resident consumption through the structure decomposition.Conclusion indicates:From 1992 to 1997, the mean of the implicit carbon emissions of each industrial department in Xinjiang had been rising; From 1997 to 2007, the mean of the implicit carbon emissions of each industrial department had been declining;The implicit carbon emissions of Hydropower industry, the fire power and other seven similar industrial department were higher than that of each industrial department so that Xinjiang should strengthen monitoring on the high energy consumption.The implicit carbon emissions of the resident consumption was still in the trend of ceaseless growth and all of that states clearly that the economic grows at the cost of the increase of the greenhouse gas emissions.Xinjiang should introduce foreign advanced production technology,further optimizing the structure of the resident consumption.

High-pressure new phase of AgN3

2021 ◽  
pp. 2150386
Author(s):  
Shifeng Niu ◽  
Ran Liu ◽  
Xuhan Shi ◽  
Zhen Yao ◽  
Bingbing Liu ◽  
...  
Keyword(s):  
High Pressure ◽  
Energy Density ◽  
Density Functional ◽  
High Energy ◽  
High Energy Density ◽  
Detonation Properties ◽  
Ambient Conditions ◽  
Structure Search ◽  
Enthalpy Difference ◽  
High Energy Density Material

The structural evolutionary behaviors of AgN3 have been studied by using the particle swarm optimization structure search method combined with the density functional theory. One stable high-pressure metal polymeric phase with the [Formula: see text] space group is suggested. The enthalpy difference analysis indicates that the Ibam-AgN3 phase will transfer to the I4/mcm-AgN3 phase at 4.7 GPa and then to the [Formula: see text]-AgN3 phase at 24 GPa. The [Formula: see text]-AgN3 structure is composed of armchair–antiarmchair N-chain, in which all the N atoms are sp2 hybridization. The inherent stability of the armchair–antiarmchair chain and the anion–cation interaction between the N-chain and Ag atom induce a high stability of the [Formula: see text]-AgN3 phase, which can be captured at ambient conditions and hold its stable structure up to 1400 K. The exhibited high energy density (1.88 KJ/g) and prominent detonation properties ([Formula: see text] Km/s; [Formula: see text] GPa) of the [Formula: see text]-AgN3 phase make it a potentially high energy density material.

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