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1.
Geoscientific Model Development ; 16(11):3313-3334, 2023.
Article in English | ProQuest Central | ID: covidwho-20245068

ABSTRACT

Using climate-optimized flight trajectories is one essential measure to reduce aviation's climate impact. Detailed knowledge of temporal and spatial climate sensitivity for aviation emissions in the atmosphere is required to realize such a climate mitigation measure. The algorithmic Climate Change Functions (aCCFs) represent the basis for such purposes. This paper presents the first version of the Algorithmic Climate Change Function submodel (ACCF 1.0) within the European Centre HAMburg general circulation model (ECHAM) and Modular Earth Submodel System (MESSy) Atmospheric Chemistry (EMAC) model framework. In the ACCF 1.0, we implement a set of aCCFs (version 1.0) to estimate the average temperature response over 20 years (ATR20) resulting from aviation CO2 emissions and non-CO2 impacts, such as NOx emissions (via ozone production and methane destruction), water vapour emissions, and contrail cirrus. While the aCCF concept has been introduced in previous research, here, we publish a consistent set of aCCF formulas in terms of fuel scenario, metric, and efficacy for the first time. In particular, this paper elaborates on contrail aCCF development, which has not been published before. ACCF 1.0 uses the simulated atmospheric conditions at the emission location as input to calculate the ATR20 per unit of fuel burned, per NOx emitted, or per flown kilometre.In this research, we perform quality checks of the ACCF 1.0 outputs in two aspects. Firstly, we compare climatological values calculated by ACCF 1.0 to previous studies. The comparison confirms that in the Northern Hemisphere between 150–300 hPa altitude (flight corridor), the vertical and latitudinal structure of NOx-induced ozone and H2O effects are well represented by the ACCF model output. The NOx-induced methane effects increase towards lower altitudes and higher latitudes, which behaves differently from the existing literature. For contrail cirrus, the climatological pattern of the ACCF model output corresponds with the literature, except that contrail-cirrus aCCF generates values at low altitudes near polar regions, which is caused by the conditions set up for contrail formation. Secondly, we evaluate the reduction of NOx-induced ozone effects through trajectory optimization, employing the tagging chemistry approach (contribution approach to tag species according to their emission categories and to inherit these tags to other species during the subsequent chemical reactions). The simulation results show that climate-optimized trajectories reduce the radiative forcing contribution from aviation NOx-induced ozone compared to cost-optimized trajectories. Finally, we couple the ACCF 1.0 to the air traffic simulation submodel AirTraf version 2.0 and demonstrate the variability of the flight trajectories when the efficacy of individual effects is considered. Based on the 1 d simulation results of a subset of European flights, the total ATR20 of the climate-optimized flights is significantly lower (roughly 50 % less) than that of the cost-optimized flights, with the most considerable contribution from contrail cirrus. The CO2 contribution observed in this study is low compared with the non-CO2 effects, which requires further diagnosis.

2.
LC GC North America ; 39(6):291-292, 2021.
Article in English | ProQuest Central | ID: covidwho-20244058
3.
LC GC North America ; 38(6):320-324, 2020.
Article in English | ProQuest Central | ID: covidwho-20243314

ABSTRACT

Aside from evaporation of water from buffer solutions, precipitation of buffer salts can also easily occur when a buffer solution comes into contact with a pure organic solvent. [...]one should avoid- at all costs-a situation where a LC system component containing an aqueous buffer is flushed immediately with a pure organic solvent. Solvents and Buffers Figure 1 shows a picture of a buffer bottle I observed in an LC laboratory about a year ago. Many of the aqueous buffer solutions used in LC (and even high-performance liquid chromatography [HPLC] grade water, if given enough time and exposure to aboratory dust) are environments quite favorable to microbes, particularly those in the middle of the pH range.

4.
LC GC North America ; 38(5):277-284,288-290, 2020.
Article in English | ProQuest Central | ID: covidwho-20243105

ABSTRACT

Among Armstrong's many accomplishments is the development of ionic liquid stationary phases for capillary GC. [...]the American Chemical Society Division of Analytical Chemistry Satinder Ahuja New Investigator Award in Separation Science was presented to. Table III provides a listing of accessories and consumables launched over the past year. Besides several short courses associated with Pittcon, additional training and educational resources are available for 2020.

5.
Beijing da xue xue bao ; Yi xue ban = Journal of Peking University. Health sciences. 54(5):907-919, 2022.
Article in Chinese | EMBASE | ID: covidwho-20242746

ABSTRACT

OBJECTIVE: Jingfang Granules have been recommended for the prevention and treatment of corona virus disease 2019 (COVID-19). Through chemical analysis and bioactivity evaluation, this study aims to elucidate the potential effective components of Jingfang Granules. METHOD(S): The inhibitory acti-vities of Jingfang Granules extract against 3-chymotrypsin-like protease (3CLpro), papain like protease (PLpro), spike protein receptor-binding domain (S-RBD) and human cyclooxygenase-2 (COX-2) were evaluated using enzyme assay. The antitussive effects were evaluated using the classical ammonia-induced cough model. The chemical constituents of Jingfang Granules were qualitatively and quantitatively analyzed by liquid chromatography-mass spectrometry (LC/MS). The 3CLpro and PLpro inhibitory activities of the major compounds were determined by enzyme assay, molecular docking, and site-directed mutagenesis. RESULT(S): Jingfang Granules exhibited 3CLpro and PLpro inhibitory activities, as well as COX-2 inhibitory and antitussive activities. By investigating the MS/MS behaviors of reference standards, a total of fifty-six compounds were characterized in Jingfang Granules. Sixteen of them were unambiguously identified by comparing with reference standards. The contents of the 16 major compounds were also determined, and their total contents were 2 498.8 mug/g. Naringin, nodakenin and neohesperidin were three dominating compounds in Jingfang Granules, and their contents were 688.8, 596.4 and 578.7 mug/g, respectively. In addition, neohesperidin and naringin exhibited PLpro inhibitory activities, and the inhibition rates at 8 mumol/L were 53.5% and 46.1%, respectively. Prim-O-glucosylcimifugin showed significant inhibitory activities against 3CLpro and PLpro, and the inhibitory rates at 8 mumol/L were 76.8% and 78.2%, respectively. Molecular docking indicated that hydrogen bonds could be formed between prim-O-glucosylcimifugin and amino acid residues H163, E166, Q192, T190 of 3CLpro (binding energy, -7.7 kcal/mol) and K157, D164, R166, E167, T301 of PLpro(-7.3 kcal/mol), respectively. Site-directed mutagenesis indicated amino acid residue K157 was a key active site for the interaction between prim-O-glucosylcimifugin and PLpro. CONCLUSION(S): Prim-O-glucosylcimifugin, neohesperidin, and naringin as the major compounds from Jingfang Granules could inhibit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus proteases 3CLpro and PLpro. The results are valuable for rational clinical use of Jingfang Granules.

6.
Profilakticheskaya Meditsina ; 26(4):77-85, 2023.
Article in Russian | EMBASE | ID: covidwho-20242706

ABSTRACT

Coronavirus disease has many systemic disease symptoms and has severe consequences for the cardiovascular system. Objective. To assess the role of clinical and laboratory indicators in determining the risk of chronic heart failure (CHF) in COV-ID-19 survivors. Material and methods. In total, 151 patients treated in a monoinfectious hospital from 03.11.20 to 10.02.21 with a confirmed diagnosis of COVID-19 were retrospectively selected. Medical history and laboratory data were collected by reviewing electronic medical records. The data included age, gender, body mass index, smoking status, and comorbidities. The laboratory data included the results of hematology and blood chemistry, coagulation, and the levels of acute-phase proteins. The CHF occurrence was used as the study endpoint. Results and discussion. The study patients were divided into two groups depending on the presence of CHF: group 1 included 46 patients with CHF, and group 2 included 105 patients without CHF. The median age was 66.2 (50-92) years;91 (60.3%) were females. Laboratory tests, such as levels of the hs-C-reactive protein, lactate dehydrogenase, procalcitonin, creatinine, and bilirubin, were statistically significantly different in patients of the study groups, and the median values were higher in patients with CHF. Neutrophil-lymphocyte ratio (NLR) showed statistically significant differences between groups: in patients with CHF, the median was 4.97% compared to 3.62% (p=0.011) in those without CHF. The most significant predictors of an increased risk of CHF were age >=66 years (OR=8.038, p<0.001), procalcitonin level >=0.09 ng/mL (increased the CHF risk by 3.8 times, p<0.001), thrombocy-topenia <=220x109/L (p=0.010), an NLR ratio >=4.11% (p=0.010), and a history of chronic kidney disease (p=0.018). Conclusion. A model has been developed to determine the factors closely associated with the risk of chronic heart failure in CO-VID-19 survivors.Copyright © 2023, Media Sphera Publishing Group. All rights reserved.

7.
LC GC North America ; 38(7):422, 2020.
Article in English | ProQuest Central | ID: covidwho-20242579

ABSTRACT

[...]after many such changes, relearning and reentering information into new profiles and management systems lost its luster. While believe that lecture course content can be delivered effectively online, there is an undeniable need for extensive hands-on laboratory experimentation in a physical science curriculum. [...]it provides more opportunities to reiterate key points to the students.

8.
LC GC North America ; 41(5):181-185, 2023.
Article in English | ProQuest Central | ID: covidwho-20241824

ABSTRACT

[...]instrument-based sample preparation technologies are presented. [...]attention is turned to other sample preparation accessories and supporting technologies. First is the Swift HLB-DPX tips. First is the Thermo Scientific AccelerOme sample preparation platform automating sample preparation for liquid chroma-tography-mass spectrometry (LC-MS) proteomics.

9.
International Journal of Applied Pharmaceutics ; 15(Special Issue 1):51-55, 2023.
Article in English | EMBASE | ID: covidwho-20240315

ABSTRACT

Objective: To design an optimal formulation for quercetin and vitamin C nano-phytosome. Method(s): Nano-phytosomes are prepared by the thin layer hydration technique using a 2-level-5-factor design experimental. A total of 32 experimental formulas were used for data analysis. The ratio of quercetin: soy lecithin (X1), the ratio of quercetin: cholesterol (X2), stirring speed (X3), stirring temperature (X4), and stirring time (X5) were used as independent factors, while globule size as a dependent factor. Data analysis was carried out by Design Expert12 application. Characterization of the optimal formula included physicochemical evaluation, globule size analysis, zeta potential, polydispersity index, entrapment efficiency, Transition Electron Microscopy (TEM) analysis, and FTIR analysis. Result(s): The optimal formula consisted of quercetin: vitamin C: lecithin: cholesterol ratio of 1: 1: 1.046: 0.105 mol;stirring speed 763.986 rpm;stirring time of 59 min, at temperature 51.73 degreeC which produced 59.26 nm average globule size, PDI value 0.66;zeta potential value-35.93+/-0.95 mV and average SPAN value 0.61. This formulation showed entrapment efficiency of quercetin 91.69+/-0.18 % and vitamin C 90.82+/-0.13 %. The TEM and FITR analysis showed the morphological of the globules and interactions between the drugs, soy lecithin, and cholesterol to form nano-phytosomes. Conclusion(s): The conditions to obtain the optimal formula for quercetin vitamin C nano-phytosome consisted of quercetin: vitamin C: lecithin: cholesterol ratio of 1: 1: 1.046: 0.105 mol;stirring speed 763.986 rpm;stirring time of 59 min, and at temperature 51.73 degreeC.Copyright © 2023 The Authors.

10.
Pharmaceutical Technology Europe ; 32(12):37-38,40, 2020.
Article in English | ProQuest Central | ID: covidwho-20239313

ABSTRACT

CDMOs need to gauge their internal capacity of temperature storage units, form strategic partnerships with logistics companies, and potentially offer validated temperature storage of clinical trial material. Through the use of secure document sharing platforms, remote viewing systems, and virtual site tours, clients can be assured they will be able to perform a thorough review of facilities and quality systems and have connections with the subject matter experts and remote access to live action activities to meet their programme requirements and quality standards. To ensure projects continue to run to time, it is vital that upper management and business development have the ability to check in constantly. Hoerner (Purisys): Modelling and simulation tools have been extremely valuable to reduce the amount of work required for scale-up;for example, engineering technologies such as Scale-up Systems' Dynochem can model solvent swaps, drying, distillation, off-gassing, and many other fundamental elements of synthetic and chemical processes.

11.
Food and Fermentation Industries ; 49(8):335-341, 2023.
Article in Chinese | CAB Abstracts | ID: covidwho-20238658

ABSTRACT

Sulforaphane is an isothiocyanate metabolite of cruciferous plants, which obtain antioxidant, anticancer and anti-COVID-19 functions. However, due to its unstable structure, it is easy to de-composite, thus the utilization of sulforaphane is difficult. With the advancement of the preparation of sulforaphane, the purpose of inhibiting sulforaphane inactivation and improving its utilization is expected to be realized. The existing preparation technologies are mainly myrosinase enzymatic hydrolysis, microbial transformation and chemical synthesis. Myrosinase enzymatic hydrolysis mainly utilizes endogenous myrosinase, exogenous myrosinase and heterologously expressed myrosinase. Myrosinase enzymatic hydrolysis technology not only obtain the advantage of high preparation efficiency, but also obtain the disadvantage that the activity of myrosinase cannot be stabilized. Microbial transformation mainly utilizes the function of microorganisms to convert glucosinolates to sulforaphane, and obtain the advantages of easy control of reaction conditions and low cost. Chemical synthesis mainly includes de novo synthesis and semi-synthesis, and semi-synthesis is the most widely used method at present. Chemical synthesis obtains the advantages of easy control of reaction conditions, but chemical synthesis techniques have the problems of high risk and low yield. This research reviews the preparation technology of sulforaphane, aiming to provide a reference for the efficient utilization of sulforaphane and its product development.

12.
LC GC North America ; 39(2):106, 2021.
Article in English | ProQuest Central | ID: covidwho-20236727

ABSTRACT

Before New Year's Day, mil-ions of Americans had received the vaccine, including front-line physicians, health care providers, and nursing home patients, our most vulnerable citizens. David Pride, MD, a microbiologist at the University of California San Diego, estimates that vaccines typically take 10-15 years to develop. [...]the COVID-19 pandemic, the fastest development timeline was four years, for the mumps vaccine. * Many government systems moved quickly to lessen the burden of onerous regulations, and provide funding so that vaccines could be developed quickly, but with still rigorous standards. After health care workers and our most vulnerable citizens, other frontline workers will be next.

13.
LC GC North America ; 39(7):307, 2021.
Article in English | ProQuest Central | ID: covidwho-20236722

ABSTRACT

Early on, whispers of a potentially engineered virus grew and fueled speculation that China was behind the pandemic-speculation so pervasive that, in February 2020, a group of 27 public health scientists published a letter in The Lancet disputing the laboratory leak theory, and announcing their support of their counterparts in China-the scientists, public health officials, and medical professionals-combating the pandemic. Robert Malone, MD, the inventor of the mRNA technology, has expressed strong concern over the risk-benefit analysis of vaccinating young adults, and the Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices has met to discuss cases of myocarditis or pericarditis in people aged 30 and younger who have received an mRNA Covid-19 vaccine. What we do know for certain is that the incredible strength and collaboration of the scientific community have allowed us to regain some semblance of normalcy.

14.
LC GC North America ; 40(5):229-231, 2022.
Article in English | ProQuest Central | ID: covidwho-20236205

ABSTRACT

Reducing the molecule complexity is achieved by reducing the molecule size after enzymatic digestion to produce smaller fragments more amenable to LC separation and tandem mass spectrometry (MS/MS) sequencing. Non-denaturing CEX chromatography, size-exclusion chromatogra- phy (SEC), hydrophobic interaction chromatography (HIC), and protein A modes can be easily coupled to reversed-phase LC (RPLC) because of the high aqueous conditions, enabling the versatile 4D-LC-MS systems with the use of alternative modes to 1D CEX, such as SEC or Protein A (6,7). [...]the nanopar-ticle size and free drug concentration are determined at the particle Level, whereas the encapsulated drug and lipids forming the layer are commonly characterized at the molecuar level after denaturing the lipid nanoparticle (LNP) via a surfactant. [...]MDLC-MS setups present a formidable opportunity to unify the characterization of drug delivery systems at the molecular and particle evels, which would enable their high throughput analysis.

15.
Shanlax International Journal of Education ; 11:61-75, 2023.
Article in English | ProQuest Central | ID: covidwho-20235909

ABSTRACT

Due to the COVID-19 pandemic, mandatory changes were required in the field of education, as in many other fields. One of these fields is a teacher training programme, which includes teaching practice. It has become of great importance that pre-service science teachers, who frequently include experiments in their teaching practices in face-to-face education, will carry out this process in online education. This process, experienced due to the COVID-19 pandemic, prompted pre-service science teachers to find something that could replace the wet labs. One of the solutions in this situation is for them to choose and use appropriate Web 2.0 tools in their online lab teaching practices. Therefore, the purpose of the study was to examine the Web 2.0 tools used by pre-service chemistry teachers in their online teaching practices in a distance education environment, the purposes of using these tools, and their justifications for preferences to use these tools. This study was conducted with 15 pre-service chemistry teachers. Data were collected via observations, a form filled out by the participants, and semi-structured interviews in this study. According to the results of this study, it was determined that the participants used 17 Web 2.0 tools during their online teaching practices. The findings highlighted that the most used Web 2.0 tools were Perculus+ chat, Google docs, and Quizizz. Moreover, it was determined that the participants used these tools for 21 different purposes such as drawing students' attention, getting hypotheses, and designing experiments. The results also indicated that the participants emphasised the ease of the Web 2.0 tool as a justification for the preference for almost all of the Web 2.0 tools they use, regardless of their purposes for using these tools. It is thought that the results can be used to show how to make online or face-to-face teaching practices in teacher training programmes by using Web 2.0 tools more effective in the future.

16.
LC GC North America ; 38(10):562-563, 2020.
Article in English | ProQuest Central | ID: covidwho-20234501

ABSTRACT

[...]we did, and we discussed digital transformation's evolution and how laboratories can benefit, too. Curtis: This is a term that's used in so many different contexts that it's important to step back and understand that it's not just about focusing on a micro-component of the work process in your laboratory, but about identifying and addressing a given process end to end. Specifically, you want to improve data capture throughout the entire process. [...]any type of digital transformation is about tackling the end-to-end process rather than any single system, which tends to be a very tactical approach. Digital transformation creates the opportunity to support remote teams and be much more flexible and effective with human capital.

17.
Yaoxue Xuebao ; 58(4):826-833, 2023.
Article in Chinese | EMBASE | ID: covidwho-20234481

ABSTRACT

Nucleic acids, as a next generation of biotechnology drugs, not only can fundamentally treat diseases, but also own significant platform characteristics in view of technology and production. Therefore, nucleic acid-based drugs have broad clinical applications in biomedical fields. However, nucleic acids are degradable and unstable, and have very low intracellular delivery efficiency in vitro and in vivo, which greatly limits their applications. In recent years, ionizable lipid-based lipid nanoparticles have shown promising application potentials and have been successfully applied to COVID-19 (Coronavirus Disease 2019) vaccines in clinic. Lipid nanoparticles demonstrate high in vivo delivery efficiency and good safety profile due to their unique structural and physicochemical properties, which provides many possibilities for their clinical applications for nucleic acid delivery in the future. This review focused on the characteristics of nucleic acid drugs and their delivery barriers, and discussed the approved nucleic acid drugs to illustrate the key aspects of the success of their delivery carrier system. In addition, problems to be solved in the field were highlighted.Copyright © 2023, Chinese Pharmaceutical Association. All rights reserved.

18.
Journal of Chemical Education ; 2022.
Article in English | Scopus | ID: covidwho-20233347

ABSTRACT

Especially since the Covid-19 pandemic when teachers might have found or created videos for students to watch, flipped classroom methodology has interested many secondary-level chemistry teachers. However, as the secondary coauthor teachers here found, most of the research on the effectiveness of flipped classroom methodology has been performed at the collegiate level. To help fill this gap, six high school teachers from different schools present their research and experience with flipped classroom methodologies in their classes. Taken as a collective, their research, aligning with previous research, suggests that there likely will not be gains on exam scores or course grades for high school students when a classroom is "flipped”, but there are other positive reasons that flipped classroom methodology might be a useful tool in the secondary-level chemistry classroom. © 2023 American Chemical Society and Division of Chemical Education, Inc.

19.
LC GC North America ; 40(3):125-127, 2022.
Article in English | ProQuest Central | ID: covidwho-20232686

ABSTRACT

In 2002, the first fully humanized mAb was approved by the U.S. Food and Drug Administration (FDA) (3). [...]the biopharmaceutical industry is still in its infancy and new, more complex products are in development and will ikely dominant the market in the future. [...]the most common forms of LC-MS have limitations when characterizing large macromolecules (4). [...]in this column, we discuss the potential for charge detection MS (CDMS) as an analytical tool for characterizing large, complex, and heterogenous biopharmaceuticals. [...]in October 2021 at the American Association for Mass Spectrometry (ASMS) annua meeting in Philadelphia, TrueMass presented the first commercial CDMS (6,7). The cylinder is often inside an electrostatic linear ion trap (ELIT) instrument, where ions oscillate back and forth. [...]the oscillation frequency gives the m/z and the charge is determined by the magnitude.

20.
LC GC North America ; 39(1):19-21, 2021.
Article in English | ProQuest Central | ID: covidwho-20232412

ABSTRACT

The people who work at companies that manufacture chromatography instruments and consumables are often well positioned to be aware of developments, needs, and trends that not everyone else sees, because they serve customers in a range of areas of focus and with diverse demands-such as academic researchers investigating fundamental aspects of separation science techniques, industrial analysts solving problems that they may not be allowed to talk about at conferences, or chemists working in government laboratories in areas like environmental research. Inaccurate data can be generated from variable, glass vial surface chemistries, which can lead to investigations or flawed decisions can be made from these results. The Reduced Surface Activity (RSA(tm)) Glass Technology was developed to address these issues, and to provide chemists with sample containers for LC-MS, MS, HPLC, GC, and CE that deliver reliable, consistent results by not adsorbing basic analytes, or adding metals to, or changing the pH of the diluent. The stringent RSA manufacturing processes are continued through to final contaminate-free packaging and quality control, where they are tested for adsorption, metal content, and residual materials.

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