optimal separation
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Children ◽  
2022 ◽  
Vol 9 (1) ◽  
pp. 41
Author(s):  
Désirée Caselli ◽  
Claudio Cafagno ◽  
Daniela Loconsole ◽  
Annamaria Giannini ◽  
Francesco Tansella ◽  
...  

The strategy for the selection of patients with a suspected SARS-CoV-2 infection is relevant for the organization of a children’s hospital to provide optimal separation into COVID-19 and non-COVID-19 areas and pathways. We analyzed the proportion of children with COVID-19 presenting with gastrointestinal (GI) symptoms in 137 consecutive patients admitted between January 2020 and August 2021. GI symptoms were present as follows: diarrhea in 35 patients (26%), vomiting in 16 (12%), and both of them in five (3%); the combination of fever, respiratory symptoms, and diarrhea was observed in 16 patients (12%). Of the 676 adult patients with COVID-19 admitted to our hospital in the same time interval, 62 (9.2%) had diarrhea, 30 (4.4%) had vomiting, and 11 (1.6%) had nausea; only one patient, a 38-year-old male, presented with isolated GI symptoms at the diagnosis. Although diarrhea was observed in one quarter of cases, one-half of them had the complete triad of fever, respiratory syndrome, and diarrhea, and only five had isolated diarrhea, of which two were diagnosed with a Campylobacter infection. The occurrence of either respiratory symptoms or gastrointestinal symptoms in our patients was not related to the patient age, while younger children were more likely to have a fever. Of the 137 patients, 73 (53%) could be tested for their serum level of SARS-CoV-2 specific IgG antibodies. The observed titer ranged between 0 (n = 3) and 1729 BAU/mL (median, 425 BAU/mL). Of 137 consecutive patients with COVID-19 admitted to our referral children’s hospital, only three presented with an isolated GI manifestation. It is interesting to note that this finding turned out to be fully in keeping with what was observed on adult patients with COVID-19 in our hospital. The additive diagnostic impact of gastrointestinal involvement for the triage of children with suspected COVID-19 appears limited.


Symmetry ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2186
Author(s):  
Melania Cârcu-Dobrin ◽  
Gabriel Hancu ◽  
Lajos Attila Papp ◽  
Ibolya Fülöp ◽  
Hajnal Kelemen

Chirality is a property of asymmetry which determines the pharmacokinetic and pharmacological profiles of optically active pharmaceuticals. Verapamil (VER), a calcium channel blocker phenylalkylamine derivative used in the treatment of cardio-vascular diseases, is a chiral compound, marketed as a racemate, although differences between the pharmacokinetic and pharmacological attributes of the enantiomers have been reported. The aim of our study was to develop a new chiral separation method for VER enantiomers by capillary electrophoresis (CE) using cyclodextrins (CDs) as chiral selectors (CSs). After an initial screening, using different native and derivatized CDs, at four pH levels, heptakis 2,3,6-tri-O-methyl-β-CD (TM-β-CD), a neutral derivatized CD, was identified as the optimum CS. For method optimization, a preliminary univariate approach was applied to characterize the influence of analytical parameters on the separation followed by a Box–Behnken experimental design to establish the optimal separation conditions. Chiral separation of enantiomers was achieved with a resolution of 1.58 in approximately 4 min; the migration order was R-VER followed by S-VER. The method analytical performance was evaluated in terms of precision, linearity, accuracy, and robustness (applying a Plackett–Burnam experimental design). The developed method was applied for the determination of VER enantiomers in pharmaceuticals. Finally, a computer modelling of VER–CD complexes was used to describe host–guest chiral recognition.


Entropy ◽  
2021 ◽  
Vol 23 (11) ◽  
pp. 1468
Author(s):  
Alexander Balunov ◽  
Ivan Sukin ◽  
Anatoly Tsirlin

The paper considers the limitation problem of the distillation column systems separating multicomponent mixtures with serial and parallel structures. The solution takes into account the irreversibility of processes. Using entropic balance conditions, the dependence of load on heat consumption is obtained for a binary distillation column. This dependence is parameterized through two characteristic coefficients–reversible efficiency and irreversibility factor. This dependence was used to solve problems of distribution of heat and raw material fluxes in parallel column structure and selection of optimal separation order in serial structure. The obtained results make it possible to estimate the minimum heat consumption for the separation of a given flow of raw materials, the maximum productivity, and efficiency of the system.


2021 ◽  
Vol 14 (2) ◽  
pp. 65-75
Author(s):  
Aprilia Dila Wardiningrum ◽  
Agus Dharmawan ◽  
Soni Sisbudi Harsono ◽  
Siswoyo Soekarno

Abstrak. Penelitian ini bertujuan untuk mengembangkan mesin pembersih dan pengayak tipe grizzly untuk beras sekaligus menguji kinerja mesin. Penelitian terdiri atas perancangan, perakitan, dan evaluasi kinerja mesin. Mesin yang dikembangkan memiliki 6 (enam) komponen utama, yaitu sumber dan transmisi tenaga putar, lubang pemasukan, unit pembersih beras, unit pengayak beras, lubang pengeluaran, dan kerangka mesin. Penelitian dilakukan menggunakan 3 (tiga) percobaan putaran, L (lambat), S (sedang), dan C (cepat) untuk mendapatkan data dari parameter pengukuran seperti kapasitas kerja, kecepatan putar mesin, laju isapan udara pada unit pembersih, slip putaran puli, dan persentase kehilangan bahan. Pada percobaan putaran L-S-C, yaitu 1654, 1817, dan 1979 rpm, menghasilkan laju isapan udara adalah 7,04, 7,79, dan 8,50 m/s. Slip putaran puli terjadi pada pulli 4 dengan nilai 3,27% tanpa sampal dan 1,70% dengan sampel; puli ini bertugas untuk menggetarkan ayakan grizzly 10-mesh. Kapasitas kerja pada 3 percobaan putaran (L-S-C) berturut-turut adalah 78,5, 81,6 dan 146,7 kg/jam. Pemisahan optimal dedak terjadi para percobaan putaran C sendangkan pemisahan menir terjadi pada percobaan L. Persentase kehilangan bahan tertinggi terjadi selama terjadi penurunan kecepatan putar yang mengakibatkan penurunan efektivitas kerja mesin.Design and Performance Test of Cleaning and Gryzzly-Type Sieving Machine for Rice Abstract. This research aimed to develop and a rice cleaning and grizzly-type sieving machine which also evaluates its performance. It consisted of designing, assembling, and performance evaluating of the machine. The desired machine was developed in six main components, i.e., power source, hopper, rice cleaner, rice siever, outlets, and machine frame. The research used three rotational speed treatments (Slow-Middle-Fast or L-S-C rotations) for data collections, whereas the parameters of performance testing consisted of work capacity, engine rotation speed, airflow rate, pulley rotational slip, and grain loss percentage. Engine rotation speeds at L-S-C treatments are 1654, 1817, and 1979 rpm and resulted in 7.04, 7.79, and 8.50 m/s, respectively, for airflow rates produced by the suction from a blower. The most significant rotational slip is occurred at Pulley-4 resulted in 3.27% (operating without samples) and 1.70% (operating with samples); this pulley transmitted rotational power to vibrate the 10-mesh grizzly sieve. The work capacities at L-S-C rotational treatments were 78.5, 81.6, and 146.7 kg/h, respectively. The optimal separation of brans was at C-rotational treatment, while the optimal separation of groats was at L-rotational treatment. The high percentage of grain loss occurred along with a reduction in speed that made the machine work ineffectively.


2021 ◽  
Author(s):  
Xuefei Zhu ◽  
Jinho Kim ◽  
Eduard Muljadi ◽  
R. Mark Nelms

Nanomaterials ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 2630
Author(s):  
Federica Barbaresco ◽  
Luisa Racca ◽  
Luca Spigarelli ◽  
Matteo Cocuzza ◽  
Simone Luigi Marasso ◽  
...  

This work illustrates focalization performances of a silicon-based bulk acoustic wave device applied for the separation of specimens owing to micrometric dimensions. Samples are separated in the microfluidic channel by the presence of an acoustic field, which focalizes particles or cells according to their mechanical properties compared to the surrounded medium ones. Design and fabrication processes are reported, followed by focalization performance tests conducted either with synthetic particles or cells. High focalization performances occurred at different microparticle concentrations. In addition, preliminary tests carried out with HL-60 cells highlighted an optimal separation performance at a high flow rate and when cells are mixed with micro and nanoparticles without affecting device focalization capabilities. These encouraging results showed how this bulk acoustic wave device could be exploited to develop a diagnostic tool for early diagnosis or some specific target therapies by separating different kinds of cells or biomarkers possessing different mechanical properties such as shapes, sizes and densities.


Molecules ◽  
2021 ◽  
Vol 26 (18) ◽  
pp. 5526
Author(s):  
Iván González-Veloso ◽  
Nádia M. Figueiredo ◽  
M. Natália D. S. Cordeiro

This work aims at unravelling the interactions in magnetic ionic liquids (MILs) by applying Symmetry-Adapted Perturbation Theory (SAPT) calculations, as well as based on those to set-up a polarisable force field model for these liquids. The targeted MILs comprise two different cations, namely: 1-butyl-3-methylimidazolium ([Bmim]+) and 1-ethyl-3-methylimidazolium ([Emim]+), along with several metal halides anions such as [FeCl4]−, [FeBr4]−, [ZnCl3]− and [SnCl4]2− To begin with, DFT geometry optimisations of such MILs were performed, which in turn revealed that the metallic anions prefer to stay close to the region of the carbon atom between the nitrogen atoms in the imidazolium fragment. Then, a SAPT study was carried out to find the optimal separation of the monomers and the different contributions for their interaction energy. It was found that the main contribution to the interaction energy is the electrostatic interaction component, followed by the dispersion one in most of the cases. The SAPT results were compared with those obtained by employing the local energy decomposition scheme based on the DLPNO-CCSD(T) method, the latter showing slightly lower values for the interaction energy as well as an increase of the distance between the minima centres of mass. Finally, the calculated SAPT interaction energies were found to correlate well with the melting points experimentally measured for these MILs.


2021 ◽  
Vol 11 ◽  
Author(s):  
Philippa Li ◽  
Ji Yuan ◽  
Fahad Shabbir Ahmed ◽  
Austin McHenry ◽  
Kai Fu ◽  
...  

BackgroundLymphoma-associated macrophages (LAMs) are key components in the lymphoma microenvironment, which may impact disease progression and response to therapy. There are two major subtypes of LAMs, CD68+ M1 and CD163+ M2. M2 LAMs can be transformed from M1 LAMs, particularly in certain diffuse large B-cell lymphomas (DLBCL). While mantle cell lymphoma (MCL) is well-known to contain frequent epithelioid macrophages, LAM characterization within MCL has not been fully described. Herein we evaluate the immunophenotypic subclassification, the expression of immune checkpoint molecule PD-L1, and the prognostic impact of LAMs in MCL.Materials and MethodsA total of 82 MCL cases were collected and a tissue microarray block was constructed. Immunohistochemical staining was performed using CD68 and CD163, and the positive cells were recorded manually in four representative 400× fields for each case. Multiplexed quantitative immunofluorescence assays were carried out to determine PD-L1 expression on CD68+ M1 LAMs and CD163+ M2 LAMs. In addition, we assessed Ki67 proliferation rate of MCL by an automated method using the QuPath digital imaging analysis. The cut-off points of optimal separation of overall survival (OS) were analyzed using the X-Tile software, the SPSS version 26 was used to construct survival curves, and the log-rank test was performed to calculate the p-values.ResultsMCL had a much higher count of M1 LAMs than M2 LAMs with a CD68:CD163 ratio of 3:1. Both M1 and M2 LAMs were increased in MCL cases with high Ki67 proliferation rates (>30%), in contrast to those with low Ki67 (<30%). Increased number of M1 or M2 LAMs in MCL was associated with an inferior OS. Moreover, high expression of PD-L1 on M1 LAMs had a slightly better OS than the cases with low PD-L1 expression, whereas low expression of PD-L1 on M2 LAMs had a slightly improved OS, although both were not statistically significant.ConclusionsIn contrast to DLBCL, MCL had a significantly lower rate of M1 to M2 polarization, and the high levels of M1 and M2 LAMs were associated with poor OS. Furthermore, differential PD-L1 expressions on LAMs may partially explain the different functions of tumor-suppressing or tumor-promoting of M1 and M2 LAMs, respectively.


2021 ◽  
Vol 03 (07) ◽  
pp. 1-8
Author(s):  
Isokov Maksud Uzаkovich ◽  
◽  
Alimov Rasulkhan Sarvarhanovich ◽  
Almatov Ilkhomjon Mirzabek Ugli ◽  
Somov Uliana Alexandrovna ◽  
...  

Humic substances are the main organic component of soil and water, as well as solid fossil fuels. These important components are formed during the de-composition of plant and animal residues under the influence of abiotic envi-ronmental factors and as a result of the activity of microorganisms. In the future, humic substances are of great interest for medicine, veterinary medicine and plant protection as bioregulators, biostimulants and adaptogens, which deter-mine the normal functioning of various body systems. As a result of enrichment of coal from the Angren deposit, a large amount of waste accumulates, which negatively affects the ecological situation in the region and occupies large areas, in connection with which the question of their processing arises, in particular, to obtain humic preparations and bacterial fertilizers of prolonged action. The iso-lation of humic acids from the dumps was carried out with weak solutions of po-tassium and sodium hydroxides, and then precipitated from the obtained alka-line extracts by acidification with mineral acids to pH 2.0. In the residual cakes, the synthesis of humic acids was carried out by inoculation of an association of microorganisms BK 5 grown on rice flour. In the course of the research it has been found, that optimal separation of humic acid alkali consumption solvents NaOH or KOH is 8g per 100g of the crude product in a ratio of T:F = 1:5 at a temperature of 80° C for 30 minutes.


2021 ◽  
Vol 11 (14) ◽  
pp. 6511
Author(s):  
Alessandro Quintino ◽  
Marta Cianfrini ◽  
Ivano Petracci ◽  
Vincenzo Andrea Spena ◽  
Massimo Corcione

Buoyancy-induced convection from a pair of staggered heated vertical plates suspended in free air is studied numerically with the main scope to investigate the basic heat and momentum transfer features and to determine in what measure any independent variable affects the thermal performance of each plate and both plates. A computational code based on the SIMPLE-C algorithm for pressure-velocity coupling is used to solve the system of the governing conservation equations of mass, momentum and energy. Numerical simulations are carried out for different values of the Rayleigh number based on the plate length, as well as of the horizontal separation distance between the plates and their vertical alignment, which are both normalized by the plate length. It is observed that an optimal separation distance between the plates for the maximum heat transfer rate related to the Rayleigh number and the vertical alignment of the plates does exist. Based on the results obtained, suitable dimensionless heat transfer correlations are developed for each plate and for the entire system.


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