Dispersion Ratio Research Articles

Impact of neoadjuvant immunotherapy on pulmonary function and perioperative outcomes in patients with resectable non-small cell lung cancer

Objective: To explore the effect of neoadjuvant immunotherapy on pulmonary function and the efficacy in patients with resectable non-small cell lung cancer. Methods: Data of 30 patients with non-small cell lung cancer (NSCLC) who received neoadjuvant immunotherapy before surgery in the Chest Hospital of Shanghai Jiaotong University from March 2018 to September 2021 were retrospectively collect. The efficacy and safety of neoadjuvant immunotherapy in the perioperative period and changes in pulmonary function of patients before and after neoadjuvant treatment were valuated. Results: The patients were all-male with age of (61±8)years old, The major pathological response (MPR) rate of patients receiving neoadjuvant immunotherapy was 43%(13 cases), the pathologic complete response (pCR) rate was 37% (11 cases), disease control rate (DCR) was 97% (29 cases), objective response rate (ORR) was 67% (20 cases). The forced expiratory volume in one second (FEV1) after treatment was (2.59±0.63) L, and the ratio of FEV1 to the predicted value (FEV1%pred) was 85.27%±15.86%, which were significantly higher than those before treatment [(2.48±0.59)L, 81.73%±15.94%, respectively] (P=0.013, 0.022, respectively). Forced vital capacity (FVC) after treatment was (3.59±0.77) L, which was also significantly higher than before [(3.47±0.76) L,P=0.036]; while there were no statistical difference in FEV1/FVC and FVC accounted for the proportion of predicted values (FVC%pred) between before and after treatment (P=0.084, 0.344, respectively). The ratio of carbon monoxide dispersion (DLCO) to the predicted value (DLCO%pred) decreased from 83.61%±13.10% to 78.69%±13.85% after treatment (P=0.023). There was no significant difference in the incidence of postoperative complications between the DLCO%pred decreased group and the non-decreased group (3/18 vs 0/6; P=0.546). Conclusions: Neoadjuvant immunotherapy can increase the rate of MPR and PCR, significantly increase FEV1 and FEV1%pred, but also lead to a decrease in DLCO%pred; neoadjuvant immunotherapy does not increase the incidence of postoperative complications.

PENINGKATAN DISOLUSI CELECOXIB MELALUI PEMBENTUKAN DISPERSI PADAT DENGAN HPMC-PEG 6000

ABSTRACTCelecoxib (CLX) is a drug that has low solubility and high permeability and belongs to BCS class II. The low solubility of CLX results in the bioavailability of CLX being only 40%, so it is necessary to increase the dissolution using a solid dispersion (DP) technique. This study aims to determine the dissolution profile of CLX in DP with a carrier combination of HPMC and PEG 6000. DP CLX were prepared by solvent evaporation method using drug-HPMC-PEG 6000 ratios were (1:1:1), (1:1:2) and (1:2:1). Pure CLX, physical mixture (CF) at the same ratio and DP were tested for dissolution in tribasic sodium phosphate 0.04 M (pH 12) and 1% sodium lauryl sulfate (SLS). The data from the dissolution test in the form of Q45 and DE60 values were analyzed statistically using non-parametric test. Overall Q45 DP CLX value > 75% and significantly different from pure CLX and CF. DE60 CLX value in DP ratio (1:1:1) 59.13±0.44%; ratio (1:1:2) 60.77±0.09%; ratio (1:2:1) 60.47±0.42%. Solid dispersion with a combination of HPMC polymer and PEG 6000 was able to increase the dissolution of celecoxib compared to the physical mixture and pure celecoxib.Keywords: celecoxib, dissolution, HPMC, PEG 6000, solid dispersion

Variability of soil properties in Sikhe village under Lower Subansiri district, Arunachal Pradesh

The study was conducted under three land uses, viz., terrace, jhum and forest to assess the variability of soil properties in Sikhe village under Lower Subansiri district, Arunachal Pradesh. The soil pH was strong to moderate acidic in reaction (pH 4.6 to 6.1). Organic carbon ranged from 10.7 to 46.0 g kg-1 which was found to be highest in forest ecosystem among the land uses. Cation exchange capacity (CEC) ranged between 7.9 and 22.8 cmol (p+) kg -1 and had significant positive correlation with organic carbon (r=0.68**). Bulk density varied from 1.10 to 1.56 Mg m-3, and showed significant negative correlation with organic carbon(r= -0.61*). Bulk density of forest was recorded to be the lowest. Water holding capacity (WHC) varied from 37.0 to 64.2 %, and was found higher under forest land use. WHC had significant positive correlation with organic carbon (r=0.55*) and significant negative one with sand (r=-0.62*). Hydraulic conductivity varied from 0.21 to 1.86 cm hr-1, and was found lowest under terrace land uses. Water stable aggregates (WSA > 0.25) ranged from 83.0 to 96.8 %. Mean weight diameter of the soil varied from 0.52 to 0.88 mm. The textural classes of various soils under different land use systems were loam, sandy loam and silt loam. The dispersion ratio varied from 30.2 to 47.9, which was very high in all the land uses. It had significant positive correlation with sand (r=0.76**) and significant negative correlation with organic carbon (r= -0.74**) and clay (r=-0.56**). Erosion index ranged from 48.1 to 89.9, and the highest was observed under terrace land use and lowest under forest land use. Erosion index had significant positive correlation with sand (r=0.72**) and dispersion ratio (r=0.74**) and significant negative one with organic carbon (r=-0.69**) and clay (r=-0.68**). The dispersion ratio and erosion index of all the land uses were very high indicating that the soils are highly erodible.

Variability of soil properties in Sikhe village under Lower Subansiri district, Arunachal Pradesh

The study was conducted under three land uses, viz., terrace, jhum and forest to assess the variability of soil properties in Sikhe village under Lower Subansiri district, Arunachal Pradesh. The soil pH was strong to moderate acidic in reaction (pH 4.6 to 6.1). Organic carbon ranged from 10.7 to 46.0 g kg-1 which was found to be highest in forest ecosystem among the land uses. Cation exchange capacity (CEC) ranged between 7.9 and 22.8 cmol (p+) kg -1 and had significant positive correlation with organic carbon (r=0.68**). Bulk density varied from 1.10 to 1.56 Mg m-3, and showed significant negative correlation with organic carbon(r= -0.61*). Bulk density of forest was recorded to be the lowest. Water holding capacity (WHC) varied from 37.0 to 64.2 %, and was found higher under forest land use. WHC had significant positive correlation with organic carbon (r=0.55*) and significant negative one with sand (r=-0.62*). Hydraulic conductivity varied from 0.21 to 1.86 cm hr-1, and was found lowest under terrace land uses. Water stable aggregates (WSA > 0.25) ranged from 83.0 to 96.8 %. Mean weight diameter of the soil varied from 0.52 to 0.88 mm. The textural classes of various soils under different land use systems were loam, sandy loam and silt loam. The dispersion ratio varied from 30.2 to 47.9, which was very high in all the land uses. It had significant positive correlation with sand (r=0.76**) and significant negative correlation with organic carbon (r= -0.74**) and clay (r=-0.56**). Erosion index ranged from 48.1 to 89.9, and the highest was observed under terrace land use and lowest under forest land use. Erosion index had significant positive correlation with sand (r=0.72**) and dispersion ratio (r=0.74**) and significant negative one with organic carbon (r=-0.69**) and clay (r=-0.68**). The dispersion ratio and erosion index of all the land uses were very high indicating that the soils are highly erodible.

Protective Effects of Trehalose and Pentoxifylline on Goat Sperm Exposed to Chilling-Freezing Process.

Freezing of sperm is known as an important part of assisted reproduction. However, many studies have illustrated that cryopreservation negatively affects the quality and fertility rate of sperm. This study aimed to evaluate the effects of trehalose and pentoxifylline (PTX) in diluents on cooled and frozen-thawed Markhoz goat sperm. Preassessed samples were pooled and diluted with a basic diluent using trehalose and PTX. The cooled sperm showed significant improvement. The motion characteristics of cryopreserved sperm were evaluated based on computer-assisted system analysis. In this study, we investigated the viability, membrane integrity, malondialdehyde concentration, total abnormality, acrosome integrity, and seminal hyaluronidase enzyme. Also, the hypo-osmotic swelling test, mitochondrial activity, apoptotic features, caspase activity, chromatin dispersion test, active mitochondria, and reactive oxygen species (ROS) activity were assessed as complementary parameters. The data illustrate that the total motility, progressive motility, average path velocity (VAP), straight-line velocity (VSL), curvilinear velocity (VCL), and the ratio of sperm chromatin dispersion, viable sperm were improved significantly (p < 0.05) using 3 mM PTX alone or 3 mM PTX plus 50 mM trehalose, while other characteristics indicate significant enhancement by 3 and 6 mM PTX and 50 and 70 mM trehalose alone or in combination, except amplitude of lateral head displacement (ALH), beat/cross frequency (BCF), and intracellular ROS-(O-), which demonstrate no significant difference among treatments. In conclusion, this study indicates that addition of 3 and 6 mM PTX alone or with 50 and 70 mM trehalose seems to reduce the damage caused by cooling and cryopreservation processes.

Effect of Land Uses on Soil Erodibility in the Njala Area of Southern Sierra Leone

Soil loss through erosion continues to pose serious challenges to increasing the smallholder agricultural productivity in Sierra Leone. While emphasis on sustainable land use practices continue to gain attention among land users, however, the rate of adoption among smallholder farmers is still very low and hence, in most part of the country soil fertility has been declining at alarming rates. In the Njala area, studies have shown that soil loss ranges from moderate to high. Though soil erosion has been identified as a major soil fertility declining factor, however, the effect of land use practices on the inherent resistance of soil materials to erosion is lacking. This study was therefore conducted to assess the effect of land uses on soil erodibility. The results showed that the soils are coarse sandy loam with high sand content. The dispersion ratios and erosion indices of soils under cassava, plantain, maize and guava were above the minimum thresholds of 15.0 and 10.0 respectively, thus indicating that these soils are highly erodible compared to soils under fallow and sweet potato which have dispersion ratios and erosion indices below the minimum thresholds. Clay content was inversely proportional to and significantly correlated with dispersion ratio and erosion index while the correlations between silt + clay, dispersion ration and erosion index, and silt, silt + clay and dispersion ratio were negative and non-significant. Considering the coarse nature of soils, landscape features and high erodibility indices, these soils would need special soil and water conservation practices to counter further degradation. These may include following, agroforestry, silvi-pasture, controlled and rotational grazing. In addition, awareness of sense of self-responsibility and forest policies and regulations are needed.

Features of determining the specific surface area of powdered quartz-containing systems

Introduction. Mineral raw materials, mechanically dispersed to a fine-grained condition, contribute to the effective use of the energy potential in the course of the structuring of composite materials. An important parameter, characterizing the dispersion ability and allowing to evaluate the ability of the system to transform is the specific surface of the substance. The experimental value of the specific surface depends on the measurement method and may differ for the same solids when different methods are applied. The purpose of the work is to study the morphological features of the surface of powdered quartz-containing systems having varying degrees of dispersion. The work represents the experimental identification of specific surface.&#x0D; Materials and methods. Filtration and adsorption methods were used to identify the specific surface of a mechanically activated sample of polymineral sand. Fine powders of sand were obtained by dry grinding in a planetary ball mill. The analysis of the obtained results was conducted taking into account the surface tension values of the powders as the characteristics of the surface energy of a surface area unit.&#x0D; Results. It is found that dimensions of the specific surface identified using the gas filtration method are smaller than those obtained using the nitrogen adsorption method. The authors have identified a linear functional dependence between the ratio of dispersion and polarization components of the surface tension and the ratio of specific surfaces obtained using different methods for one sample of sand.&#x0D; Conclusions. Despite a difference in the values obtained for the same material sample, specific surface area indicators, identified using different methods, allow to evaluate the extent of the surface maturity, the availability of active centres, and the energy potential of mineral powders. The ratio of specific surfaces can be used as a criterion for the rational choice of the operating parameters of mechanical activation of quartz-containing powder systems to increase the energy potential of the surface.

Research of a modified nano-depressure and augmented injection agent

In this paper, the research and application of nanomaterials in oilfield chemical engineering was briefly described with emphasis on the nano-silica in enhanced oil recovery, depressure and augmented injection. A study on the modification of nano-silica was carried out indoors, and a modified nano-depressure and augmented injection agent was prepared by using a coupling agent for surface grafting modification, followed by introducing functional monomers for in-situ modification. The effects of silica dosage, coupling agent dosage, dispersant and regulator ratio, and modification time on the modified product were investigated. It was analyzed by infrared spectroscopy, thermogravimetric analysis, nanoparticle size analyzer, transmission electron microscope, atomic force microscope, etc. A series of experiments were conducted to evaluate the temperature and salt resistance, wettability, as well as depressure and augmented injection performance of the modified products.

Enumeration of carbon and nitrogen contents of water-stable aggregates in layers of topsoils from cultivated and adjacent bush-fallow loamy soils

Soil organic carbon (SOC) and total soil nitrogen (TSN) dynamics have both pedological and agronomic basis. Knowledge of their retention within aggregate hierarchies of varying soil textures as influenced by land use change is limited. The capacity of loam (L), clay loam (CL), sandy loam (SL) and sandy clay loam (SCL) soils to retain SOC and TSN in water-stable aggregate (WSA) at 10-cm intervals of 0-30 cm topsoil depths under cultivated and bushfallow/ uncultivated systems was investigated. The soils showed high dispersion ratio and great variations in aggregate silt and clay indices (CL &gt; L &gt; SCL &gt; SL) under both land uses. Across soil depths, the uncultivated CL, SL and SCL soils had moderate to high &gt; 2.00 mm WSA whose reduction due to cultivation impact was more pronounced in SL than in CL soil. Across soil depths and land uses, SOC content seemed higher in the macro- (&gt; 0.50 mm) than in the micro- (&lt; 0.50 mm) aggregates of all the soils while the reverse marked aggregate TSN content in almost all the soils. Cultivation mostly reduced macro-aggregate-associated SOC and TSN in L &gt; CL &gt; SL and in L &gt; SL &gt; CL &gt; SCL soils, respectively. However, cultivation showed no reduction influence on micro-aggregate-associated SOC of all the soils. Cultivation-related reduction in micro-aggregate-associated TSN was more pronounced in the generally more ‘clayey’ CL and SCL than the L and SL soils. So, the potential of bush-fallowing to enhance micro-aggregateassociated TSN storage and stabilization against adverse influence of cultivation depends on soil texture.

Galaxy velocity bias in cosmological simulations: towards per cent-level calibration

ABSTRACT Galaxy cluster masses, rich with cosmological information, can be estimated from internal dark matter (DM) velocity dispersions, which in turn can be observationally inferred from satellite galaxy velocities. However, galaxies are biased tracers of the DM, and the bias can vary over host halo and galaxy properties as well as time. We precisely calibrate the velocity bias, bv – defined as the ratio of galaxy and DM velocity dispersions – as a function of redshift, host halo mass, and galaxy stellar mass threshold ($M_{\rm \star , sat}$), for massive haloes ($M_{\rm 200c}\gt 10^{13.5} \, {\rm M}_\odot$) from five cosmological simulations: IllustrisTNG, Magneticum, Bahamas + Macsis, The Three Hundred Project, and MultiDark Planck-2. We first compare scaling relations for galaxy and DM velocity dispersion across simulations; the former is estimated using a new ensemble velocity likelihood method that is unbiased for low galaxy counts per halo, while the latter uses a local linear regression. The simulations show consistent trends of bv increasing with M200c and decreasing with redshift and $M_{\rm \star , sat}$. The ensemble-estimated theoretical uncertainty in bv is 2–3 per cent, but becomes percent-level when considering only the three highest resolution simulations. We update the mass–richness normalization for an SDSS redMaPPer cluster sample, and find our improved bv estimates reduce the normalization uncertainty from 22 to 8 per cent, demonstrating that dynamical mass estimation is competitive with weak lensing mass estimation. We discuss necessary steps for further improving this precision. Our estimates for $b_v(M_{\rm 200c}, M_{\rm \star , sat}, z)$ are made publicly available.

Fat Cats, Production Networks, and the Right to Fair Pay

AbstractShould there be a legal right to fair pay so that anyone might challenge the relative fairness of their pay? International human rights law does not clearly support such a right, partly due to the uncertain meaning of fairness in pay. The article challenges this uncertainty, explaining the marginal relevance of theories of distributive justice. Standards of fairness should be discovered instead in principles of interpersonal justice, particularly the bilateral principle of good faith, and in associational principles of desert by reference to contribution and recognition of persons. These contain an egalitarian impulse providing moral reasons for rejecting market rates of pay and, it is argued, should apply beyond single corporate entities, to corporate groups and networks of companies sharing an integrated production scheme. Finally, appropriate regulations enacting a legal right to fair pay are explored with a view to achieving reflexive yet effective regulation using works councils to fix outer limits to wage dispersal ratios.

On the origin of surprisingly cold gas discs in galaxies at high redshift

ABSTRACT We address the puzzling observational indications for very ‘cold’ galactic discs at redshifts z ≳ 3, an epoch when discs are expected to be highly perturbed. Using a high-resolution cosmological zoom-in simulation, we identify such a cold disc at z ∼ 3.5, with a rotation velocity to velocity dispersion ratio of vϕ/σr ≃ 5 for the total gas. It forms as a result of a period of intense accretion of co-planar, co-rotating gas via cold cosmic-web streams. This thin disc survives for ∼5 orbital periods, after which it is disrupted by mergers and counter-rotating streams, longer but consistent with our estimate that a galaxy of this mass ($M_\star \sim 10^{10}\, \mathrm{M_\odot }$) typically survives merger-driven spin flips for ∼2–3 orbital periods. We find that vϕ/σr is highly sensitive to the tracer used to perform the kinematic analysis. While it is vϕ/σr ≃ 3.5 for atomic H i gas, it is vϕ/σr ≃ 8 for molecular CO and H2. This reflects the confinement of molecular gas to cold, dense clouds that reside near the disc mid-plane, while the atomic gas is spread into a turbulent and more extended thicker disc. The proposed mechanisms is a theoretical proposal that has not been validated yet with proper statistical measurements and it remains unclear whether it occurs frequently enough to explain the multiple discoveries of cold gas discs in high-z galaxies.

DEVELOPMENT OF CIPROFLOXACIN LOADED THROAT PAINT FOR THE TREATMENT OF STREP THROAT INFECTION

Objective: This study is to enhance the solubility and sustained release of ciprofloxacin (CPX) drug by amplifying the adhesive capability of formulation by forming throat paint for the Streptococcal pharyngitis, a sore throat infection. Methods: Solid dispersion was prepared by solvent evaporation technique, in which three different ratios of Polyethylene glycol-6000 (PEG-6000) were selected, and the best ratio of solid dispersion was selected after characterization including Scanning electron microscopy (SEM) and Differential scanning calorimetry (DSC) with evaluation parameters including % yield, drug content, and drug solubility. In the case of throat paint, out of six different formulations, the best formulation was selected through viscosity, in vitro mucoadhesion, in situ release study, and spreadability parameters. Results: The DSC and SEM data proved that solid dispersion has a different moiety than its ingredients but it is quite a stable form. Formulation MD-2 was selected as the best formulation which able to increase the solubility of the drug by more than 3.5 folds, at the same time it shows the highest rate of drug dissolution of 13.951 μg/ml with % yield (97.199±0.167%) and drug content (96.425%). Throat paint was formed by fusion and trituration process and out of all six formulations F3 was selected as the best formulation on the basis of Viscosity (11932 Centi poise), Spreadability (17.621), Mucoadhesion (3937.481 dyne/cm2), and drug release (90.336±0.6%). Conclusion: Solid dispersion was successfully prepared with 3.5 times of solubility enhancement capability in comparison with pure CPX drug. The throat paint releases the drug (≥3 h) in a sustained manner with high mucoadhesive force.

Effect of levetiracetam on cardiac repolarization in children with epilepsy

IntroductionEpileptic discharges occurring during seizure may affect many systems in the ictal, postictal, and interictal periods. Autonomic dysfunction and its negative impacts on the heart may cause life-threatening clinical manifestations, cardiac arrhythmias, and sudden cardiac death in epileptic patients. This study investigated the impact of levetiracetam (LEV) therapy on cardiac electrical activity in children with epilepsy. Material and methodsOur study included a total of 120 cases, comprising 40 newly diagnosed epilepsy patients, 40 epilepsy patients who had been receiving LEV therapy for at least 6 months, and 40 healthy individuals. Age at diagnosis, duration of LEV treatment, and familial history of cardiac disease were recorded in a standardized form. Electrocardiogram (ECG) parameters were calculated for all cases, echocardiography (ECHO) findings were noted, and the obtained data were compared using statistical methods. ResultsA comparison of the ECG parameters showed that the Tpeak–Tend (Tp–e) interval, and the Tp–e/QT dispersion (QTd) and Tp–e/QTc dispersion (QTcd) ratios, of the newly diagnosed epilepsy patients were statistically significantly increased compared with the other two groups (p = <0.001, p = 0.001, and p = 0.007, respectively). There were no statistically significant differences between the three groups in terms of QTd and QTcd. DiscussionThe repolarization differences in children with newly diagnosed epilepsy may have reflected early subclinical findings associated with the disease. We concluded that LEV monotherapy may make a positive contribution to early repolarization differences.

Consistency Characteristics of Dispersive Clays

Dispersive soils are characterized by three features: (1) unstable structure, (2) they are readily flocculate in water, and (3) very erodible. The use of dispersed clay soils in hydraulic structures, dams and road dams can cause serious engineering problems when this soil is not identified and used befittingly. There is a simple way to determine soil dispersion and more difficult to measure dispersion. (Atterberg’slimits) (grain size analysis), and (visible classification) are not enough to recognize between (normal clays) and (dispersive clays).ASTM tests can identify dispersive clay, these include: (double hydrometer test), (chemical tests), (Crumb test), and (Pinhole test). In this paper, the dispersed soil has been artificially prepared by adding Na2CO3 to natural clay in different proportions. The proportions are 5%, 15%, 25%, 30%, 35%, and 40% by weight. The target of this investigation is to investigate the effect of degree of dispersion of the soil on Atterberg limits. The study showed that the percentage of dispersion increases with Atterberg’slimits and the dispersion ratio and the plasticity index relationship are related by a direct relationship.

The Different Morphology of Co₃O₄ Catalysts and Application in the Abatement of Carbon Monoxide.

The increase of harmful carbon monoxide (CO) caused by incomplete combustion can affect human health even lead to suffocation. Therefore reducing the CO discharged by vehicles or factories is urgent to improve the air quality. The spinel cobalt (II, III) oxide (Co₃O₄) is an active catalyst for CO abatement. In this study, we tried to fabricate dispersing Co₃O₄ via the dispersion-precipitation method with acetic acid, formic acid, and oxalic acid as the chelating dispersants. Then, the asprepared samples were calcined at 300 ºC for 4 h to obtain active catalysts, and assigned as Co(A), Co(F) and Co(O) respectively, the amount of the dispersants used are labeled as I (0.12 mole), II (0.03 mole) and III (0.01 mole). For comparison, another CoAP sample was prepared via alkaliinduced precipitation and calcined at 300 ºC. All samples were characterized by X-ray diffraction (XRD), temperature-programmed reduction (TPR), scanning electron microscope (SEM), and nitrogen adsorption/desorption system, and the catalytic activity focused on the CO oxidation. The influence of chelating dispersant on the performance of abatement of CO was pursued in this study. Apparently, the results showed that the chelating dispersant can influence the catalytic activity of CO abatement. An optimized ratio of dispersant can improve the performance, while excess dispersant lessens the surface area and catalytic performance. The series of Co(O) samples can easily donate the active oxygen since the labile Co-O bonding and indicated the preferential performance than both Co(A) and Co(F) samples. The nanorod Co(O)-II showed preferential for CO oxidation, T50 and T90 approached 96 and 127 ºC, respectively. Also, the favorable durability of Co(O)-II sample maintains 95% conversion still for 50 h at 130 ºC and does not emerge deactivation.

Earthen construction: Demonstration of feasibility at 1/2 scale of poured clay concrete construction

Poured earth construction is a very promising alternative to cement-based construction, however it requires a large increase of productivity. Poured earth concrete can meet this issue, but is currently stabilized with cement leading to a high environmental impact. One possible solution is the use of alginate, a biopolymer, to provide a transient liquid–solid transition before the wall is effectively hardened by the long process of drying. Using design experiment, the impact of four parameters (water to binder ratio, dispersant ratio, alginate ratio and level of acidifier) has been investigated on the consistency and the mechanical properties. In this study the feasibility of the use of poured earth concrete stabilized with biopolymer is demonstrated through low wall manufacturing.

Effect of cavitation bubble on the dispersion of magnetorheological polishing fluid under ultrasonic preparation

In the ultrasonic dispersion process, the ultrasonic cavitation effect can seriously affect the dispersion efficiency of magnetorheological polishing fluid (MRPF), but the mechanism remains unclear now. Through considering the continuity equation and Vand viscosity equation of the suspension, a revised cavitation bubble dynamic model in the MRPF was developed and calculated. The effects of presence or absence of solid particles, the volume fraction of solid particles, and viscosity on the cavitation bubble motion characteristics in the MRPF were discussed. Settlement experiments of the MRPF under ultrasonic and mechanical dispersion were observed. Analysis of particle dispersion is made by trinocular biomicroscope and image processing of the microscopic morphology of the MRPF. The results show that the high volume fraction of carbonyl iron particle (CIP) will significantly weaken the cavitation effect, and the low volume fraction of green silicon carbide (GSC) has a negligible effect on the cavitation effect in the MRPF. When the liquid viscosity is greater than or equal to 0.1 Pa·s, it is inconvenient to produce micro-jets in the MRPF. The sedimentation rate of the MRPF prepared by ultrasonic dispersion is lower than mechanical dispersion when the volume fraction of CIP is between 1% and 25%. The dispersion ratio under ultrasonic dispersion is lower than that under mechanical dispersion. The experimental results fit the simulation well. It offers a theoretical basis for exploring the ultrasonic cavitation effect in the industrial application of the MRPF.

Does income inequality matter for CO2 emissions in Russian regions?

Research background: Intensive economic growth in Russian regions during recent decades has been associated with numerous environmental issues, particularly increasing CO2 emissions, as well as income inequality. To achieve sustainable development, it is necessary to resolve these issues.&#x0D; Purpose of the article: To shed light on the impact of income inequality on CO2 emissions based on Russian regional data covering the years 2004?2018.&#x0D; Methods: Gini index and decile dispersion ratio are used to measure income inequality. To study the impact of income inequality on CO2 emissions in the Russian regions, we estimate econometric models with fixed and random effects and apply GMM method. We test the hypothesis of the environmental Kuznets curve to determine the impact of economic growth on CO2 emissions.&#x0D; Findings &amp; value added: The results show that CO2 emissions increase in tandem with growth in income inequality between 10% of people with the lowest income and 10% of people with the highest income. Simultaneously, CO2 emissions decrease with growth of Gini coefficient. The hypothesis of the Environmental Kuznets Curve was confirmed based on GMM method. Our findings underscore that the activities of the extraction and manufacturing sectors, as well as energy consumption, increase CO2 emissions. The chief significance of this paper is the finding that large income gap between extremely rich and extremely poor population cohorts increases CO2 emissions. This implies that economic policy aimed at reducing income inequality in Russian regions will also reduce CO2 emissions, especially if accompanied by increased use of environmentally friendly technologies. From the international perspective, our research can be extended to study other countries and regions.

Erodibility of soils of varying land utilization types and lithologic materials in central southeastern Nigeria

&#x0D; &#x0D; &#x0D; Land use and parent materials influence behaviour of soils including responsiveness to erosion forces. The study investigated some soil properties related to erodibility in Abia and Imo States of Nigeria. Soil sampling was guided by geology and land use type. Random sampling technique was adopted in field studies. Two parent materials and three land use types were chosen for the study. In each parent material, three land use types were studied and in each land use, three soil profiles were sunk, described, and sampled using FAO procedure. Soil samples were subjected to laboratory analyses and data generated were analyzed using descriptive and inferential statistical tools. Results showed that sand sized particles ranged from 533.10 to 778.80 g kg–1 and this distribution differed significantly between parent materials. Silt content ranged from 141.70 g kg–1 in soils derived from false-bedded sandstone to 202.20 g kg–1 in shale-derived soils. Clay-sized particles ranged from 77.30 g kg–1 in soils derived from false-bedded sandstone to 264.70 g kg–1 in shale-derived soils, respectively. Water-stable aggregate ranged from 19.38% in false-bedded sandstone to 29.23% in shale-derived soils. The DR (dispersion ratio) mean values ranged between 4.26 in shale and 8.46 in false-bedded sandstone, while the CDI (clay dispersion index) mean values ranged between 2.17 in shale and 8.41 in false-bedded sandstone, respectively. The forest soils had the lowest values of both DR (6.89) and CDI (6.40) for soils of the false-bedded sandstone, 3.85 and 1.59 for those derived from shale. The clay flocculation index (CFI) had mean of 2.16 in false-bedded sandstone and 7.83 in shale. In soils of the varying land use types, the mean soil pH (H2O) ranged from 4.28 to 4.64 in soils derived from false-bedded sandstone and 4.27-5.57 in those derived from Shale. From the results, parent material and land use influenced soil erodibility parameters (water-stable aggregates, mean-weight diameter, DR, CDI, and CFI) and other soil properties such as organic carbon, bulk density, and moisture content.&#x0D; &#x0D; &#x0D;