Retention Factors Research Articles

Focusing on the corrosion resistance enhancement of HRB400 rebar by Cr addition in the marine environment

The corrosion resistance of Cr reinforced HRB400 rebar in the marine environment was investigated. The addition of Cr increases the amount of Cr(OH)3 and α-FeOOH in the passivate film, resulting in a denser passivate film structure. This enhanced passivation film inhibits localized corrosion. The pitting potential and critical chloride concentration (CTL) of the steel increased with the increase in chromium content, indicating improved corrosion resistance of the steel. On the other hand, an increase in the concentration of Cl- in solution leads to a decrease in the pitting potential and resistance of the steel, which reduces the corrosion resistance. At higher Cl- concentrations, the Cl- ions form an electrochemical interface with the steel surface, resulting in a sharp decrease in the Rf value. In addition, the gradual decrease in solution pH leads to a decrease in the pitting potential and CTL of HRB400 and 1.5Cr steel. The corrosion resistance was also found to be reduced, pH reduction accelerated the intrusion of chloride ions, which led to a severe breakdown of the passivation film.

Construction and evaluation of weight retention nomogram prediction model for women 1 year after delivery

To analyze the influencing factors of body weight retention in woman at 1 year postpartum, and to construct and evaluate a nomogram prediction model for postpartum 1-year weight retention. From September 2010 to February 2011, 468 pregnant women in the third trimester were recruited from Yuexiu District and Baiyun District Maternal and Child Health Hospital in Guangzhou, and followed up to 1 year postpartum. The basic demographic information of pregnant women was collected by self-made questionnaire. Dietary intake in the third trimester was investigated by 3-day 24-hour dietary review. The weight of women before delivery and one year after delivery were measured. According to whether the weight retention at 1 year postpartum is greater than 0 kg, the study subjects were divided into the 1-year postpartum weight retention group and weight recovery group. Logistic regression analysis were used to screen the influencing factors of weight retention at 1 year postpartum. R 4.2.3 software was used to construct the nomogram prediction model. The subject working characteristic curve, calibration curve, Hosmer-Lemeshow goodness of fit test and clinical decision curve were used to evaluate the model's differentiation, accuracy and clinical applicability. Among 329 subjects in the model training set, the 1-year postpartum weight retention was 68.09%, and the median and quartile levels of retained body weight were 5.0(3.0, 10.0)kg. After Logistic analysis, a nomogram prediction model was constructed based on five factors: pre-pregnancy body mass index(BMI), pregnancy weight gain, parity, gravitity, 0-6 months postpartum feeding pattern. The model had good discrimination(AUC_(training)=0.778, AUC_(testing)=0.767) and accuracy(Hosmer-Lemeshow test: P_(training)=0.946, P_(testing)=0.891). The 1-year postnatal weight retention nomogram model based on women's pre-pregnancy BMI, pregnancy weight gain, parity, gravitity, 0-6 months postpartum feeding pattern has good differentiation, accuracy and clinical applicability.

Retention of Doctors and Dentists to Serve in Remote Areas in Indonesia: A Discrete Choice Experiment.

Retaining doctors and dentists in remote areas of Indonesia remains a national priority of the Indonesian government. The purpose of this study was to analyze the interventions for retention of doctors and dentists in remote areas using the discrete choice experiment (DCE) approach. A DCE was conducted to investigate preferences of doctors and dentists for retention in remote areas. This research was conducted in 78 primary healthcare settings across 15 provinces in Indonesia. The conditional logit model was used to explore stated preferences for each attribute. The total number of respondents was 158, including 113 doctors and 45 dentists. In general, doctors placed the highest preference on getting priority for government scholarships to facilitate retention in remote areas (OR=5.65, p<0.001). Specifically, dentists preferred security guarantees from local government (OR = 4.87, p<0.001). Both groups valued having an official residence (OR=3.6, p<0.001) as a factor for retention in remote areas. Scholarship, security guarantees, housing facilities, and medical facilities were the most considered factors for retaining doctors and dentists in a remote area. This study confirms the importance of a combination of interventions in maintaining doctors and dentists in remote areas. Policy options in the form of non-financial and financial intervention packages can be combined to improve their retention.

Computational Studies and Synthesis of New Heterocyclics as CNS Agents.

This research work aimed to design and synthesize some new molecules of phenothiazine. The work's emphasis was on forming new phenothiazines in two series, 1-(10H-phenothiazin- 10-yl)-2-((4-(1-(phenylimino)ethyl)phenyl)amino)ethan-1-one derivatives (4a-4j) and 1-(4-((2-oxo-2- (10H-phenothiazin-10-yl)ethyl)amino)phenyl)-3-phenylprop-2-en-1-one derivatives (P1-P5). Chloroacetylation of phenothiazine was done to afford 2-chloro-1-(10H-phenothiazin-10- yl)ethan-1-one, which was further reacted with 4-amino acetophenone to produce 2-((4- acetylphenyl)amino)-1-(10H-phenothiazin-10-yl)ethan-1-one. Then, it was treated with substituted anilines and substituted benzaldehydes to produce the final derivatives 4a-4j and P1-P5, respectively. All 15 derivatives (4a-4j and P1-P5) were characterized by evaluating their Rf value, melting point, solubility, IR spectroscopy, and 1HNMR spectroscopy. Molecular docking was performed by using AutoDock Vina v.1.2.0 (The Scripps Research Institute, La Jolla, CA, USA) docking software, and the anxiolytic activity of the derivatives was assessed by using the elevated plus maze model. The designed scheme was executed in the departmental laboratory. The chemical structure of the compounds was confirmed on the basis of TLC, IR, and 1HNMR analyses. The docking study revealed a good docking score of the compounds. The Log P value of the compounds indicated their good penetration into CNS. The compounds were also screened for anxiolytic activity. Among them, compounds 4f, 4h, and P3 showed maximum activity as anti-anxiolytic agents.

An eco-friendly and cost-effective HPTLC method for quantification of COVID-19 antiviral drug and co-administered medications in spiked human plasma

The coronavirus-2 has led to a global pandemic of COVID-19 with an outbreak of severe acute respiratory syndrome leading to worldwide quarantine measures and a rise in death rates. The objective of this study is to propose a green, sensitive, and selective densitometric method to simultaneously quantify remdesivir (REM) in the presence of the co-administered drug linezolid (LNZ) and rivaroxaban (RIV) in spiked human plasma. TLC silica gel aluminum plates 60 F254 were used as the stationary phase, and the mobile phase was composed of dichloromethane (DCM): acetone (8.5:1.5, v/v) with densitometric detection at 254 nm. Well-resolved peaks have been observed with retardation factors (Rf) of 0.23, 0.53, and 0.72 for REM, LNZ, and RIV, respectively. A validation study was conducted according to ICH Q2 (R1) Guidelines. The method was rectilinear over the concentration ranges of 0.2–5.5 μg/band, 0.2–4.5 μg/band and 0.1–3.0 μg/band for REM, LNZ and RIV, respectively. The sensitivities of REM, LIN, and RIV were outstanding, with quantitation limits of 128.8, 50.5, and 55.8 ng/band, respectively. The approach has shown outstanding recoveries ranging from 98.3 to 101.2% when applied to pharmaceutical formulations and spiked human plasma. The method’s greenness was assessed using Analytical Eco-scale, GAPI, and AGREE metrics.

Developing a Machine-Learning Predictive Model for Retention of Posterior Cruciate Ligament in Patients Undergoing Total Knee Arthroplasty.

Predicting whether the posterior cruciate ligament (PCL) should be preserved during total knee arthroplasty (TKA) procedures is a complex task in the preoperative phase. The choice to either retain or excise the PCL has a substantial effect on the surgical outcomes and biomechanical integrity of the knee joint after the operation. To enhance surgeons' ability to predict the removal and retention of the PCL in patients before TKA, we developed machine learning models. We also identified significant feature factors that contribute to accurate predictions during this process. Patients' data on TKA continuously performed by a single surgeon who had intended initially to undergo implantation of cruciate-retaining (CR) prostheses was collected. During the sacrifice of PCL, we utilized anterior-stabilized (AS) tibial bearings. The dataset was split into CR and AS categories to form distinct groups. Relevant information regarding age, gender, body mass index (BMI), the affected side, and preoperative diagnosis was extracted by reviewing the medical records of the patients. To ensure the authenticity of the research, an initial step involved capturing X-ray images before the surgery. These images were then analyzed to determine the height of the medial condyle (MMH) and lateral condyle (LMH), as well as the ratios between MLW and MMH and MLW and LMH. Additionally, the insall-salvati index (ISI) was calculated, and the severity of any varus or valgus deformities was assessed. Eight machine-learning methods were developed to predict the retention of PCL in TKA. Risk factor analysis was performed using the SHApley Additive exPlanations method. A total of 307 knee joints from 266 patients were included, among which there were 254 females and 53 males. A stratified random sampling technique was used to split patients in a 70:30 ratio into a training dataset and a testing dataset. Eight machine-learning models were trained using data feeding. Except for the AUC of the LGBM Classifier, which is 0.70, the AUCs of other machine learning models are all lower than 0.70. In importance-based analysis, ISI, MMH, LMH, deformity, and age were confirmed as important predictive factors for PCL retention in operations. The LGBM Classifier model achieved the best performance in predicting PCL retention in TKA. Among the potential risk factors, ISI, MMH, LMH, and deformity played essential roles in the prediction of PCL retention.

Recruitment and retention of rural allied health professionals: a scoping review.

The purpose of this study was to understand what literature exists to comprehend demographics and predicted trends of rural allied health professionals (AHPs), person factors of rural AHPs, and recruitment and retention of rural AHPs. A scoping review was completed and reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews. Articles were analyzed using three a priori categories of recruitment and retention, person factors, and demographics and trends. Eighty articles met inclusion criteria for the review. Most of the literature came from Australia. Most research studies were qualitative or descriptive. A priori coding of the articles revealed overlap of the a priori codes across articles; however, the majority of articles related to recruitment and retention followed by demographics and trends and person factors. Recruitment and retention articles focused on strategies prior to education, during education, and recruitment and retention, with the highest number of articles focused on retention. Overall, there were no specific best strategies. Demographic data most commonly gathered were age, practice location, profession, sex, gender, previous rural placement and number of years in practice. While person factors were not as commonly written about, psychosocial factors of rural AHPs were most commonly discussed, including desire to care for others, appreciation of feeling needed, connectedness to team and community and enjoyment of the rural lifestyle. The evidence available provides an understanding of what research exists to understand recruitment and retention of AHPs from a recruitment and retention approach, person factor approach, and demographics and trends approach. Based on this scoping review, there is not a clear road map for predicting or maintaining AHPs in a rural workforce. Further research is needed to support increased recruitment and retention of AHPs in rural areas.

Production, characterization, and potential phenol content of various grades liquid smoke made from coconut shell waste (Cocos nucifera L.)

Liquid smoke contains various compounds that can be grouped into groups of phenolic compounds, acids, and groups of carbonyl compounds. These compound groups act as antimicrobials, antioxidants, flavoring, and coloring agents. Because liquid smoke can act as an antimicrobial and antioxidant, liquid smoke can be used as a preservative. Liquid smoke is classified as grade 3, 2, and 1 according to its properties and applications. The results of this research are phytochemical analysis for all variations of liquid smoke, showing the content of phenols, flavonoids, tannins, glycosides, and steroids/triterpenoids. The characterization results of various grades liquid smoke (3; 2; 1) respectively are yield (9.75% w/w; 60%v/v; 50.9%v/v), pH value (2.68; 2.46; 2.42), total acid (13.44%; 14.34%; 17.36%), specific gravity of (1.0499; 1.0435; 1.0421 g/mL), total phenol content (23.0186; 12.3135; 7.8879), Pb and Cd levels of 0.218; 0.207; 0.202 mg/L and 0.019; 0.010; 0.008mg/L. Identification using UV-Vis and FTIR spectrophotometry. Isolation using thin-layer chromatography showed that it contained flavonoids with an Rf value of 0.31, 0.31, 0.29. The conclusion was that various grades liquid smoke can be produced with appropriate characteristics and have high total phenol potential.

New Classification of Rheumatoid Arthritis Based on Immune Cells and Clinical Characteristics.

Rheumatoid arthritis (RA) is a chronic systemic immune disease characterized by joint synovitis, but there are differences in clinical manifestations and serum test results among different patients. This is a bioinformatics study. We first obtained the gene expression profile of RA and normal synovium from the database, and screened the differentially expressed immune related genes for enrichment analysis. Subsequently, we classified RA into three subtypes by unsupervised clustering of serum gene expression profiles based on immune enrichment scores. Then, the enrichment and clinical characteristics of different subtypes were analyzed. Finally, according to the infiltration of different subtypes of immune cells, diagnostic markers were screened and verified by qRT-PCR. C1 subtype is related to the increase of neutrophils, C-reactive protein and erythrocyte sedimentation rate, and joint pain is more significant in patients. C2 subtype is related to the expression of CD8+T cells and Tregs, and patients have mild joint pain symptoms. The RF value of C3 subtype is higher, and the expression of various immune cells is increased. CD4 T cells, NK cells activated, macrophages M1 and neutrophils are immune cells significantly infiltrated in synovium and serum of RA patients. IFNGR1, TRAC, IFITM1 can be used as diagnostic markers of different subtypes. In this study, RA patients were divided into different immune molecular subtypes based on gene expression profile, and immune diagnostic markers were screened, which provided a new idea for the diagnosis and treatment of RA.

The influence of three different primary treatment protocols on 5-year-old maxillary growth in patients with complete unilateral cleft lip and palate

The study evaluated the effects of three different primary treatment protocols on maxillary growth in patients aged 5 years with complete unilateral cleft lip and palate (UCLP). The secondary objective was to assess the influence of initial cleft severity, family history of class III, and status of permanent lateral incisor on maxillary growth.In total, 54 patients with non-syndromic complete UCLP were included and grouped as follows: group An underwent lip adhesion, cheilorhinoplasty associated with tibial periosteal graft for hard palate repair, and finally veloplasty; group B underwent lip adhesion, then cheilorhinoplasty with intravelar veloplasty, and finally a hard-palate repair; group C underwent cheilorhinoplasty with intravelar veloplasty and then a hard-palate repair. Five-year maxillary growth was assessed on dental models, both clinically and digitally.No difference was found with GOSLON-Yardstick scoring. Five-year measurements showed that group C tended to have the best maxillary arch morphology (p = 0.012). Initial cleft severity did not impact maxillary growth, but status of permanent lateral incisor and family history of class III did (p = 0.019 and p = 0.004, respectively).In patients aged 5 years, the two-stage approach appeared to be the least detrimental to growth development. Predictive factors for growth retardation included the absence of lateral incisor and a family history of class III.

Formulation of Salam (Syzygium polyanthum (wight) walp) Leaves Ethanolic Extract Matrix Patch and Its Evaluation

The total flavonoid content in salam leaves has an anti-inflammatory activity at a dose of 2.1% w/w. For topical anti-inflammatory, a matrix patch has a delivery mechanism that drugs pass through in the skin in a controlled for an extended period. Polymers were the patch's main component to control the drug release. Polyvinyl alcohol (PVA) and alpha-cellulose (AC) were polymers that can increase the rate of drug diffusion and form a strong film layer. Salam leaves were extracted by maceration using ethanol 96%. Matrix patches were made with a combination of PVA and AC in ratios 1:1; 3:1; 1:3. The patches were tested for physicochemical properties. The stability test was conducted at 4, 25, and 40 temperatures for 8 h, respectively. Statistical analysis of the test data used One Way ANOVA with a confidence level of 95%. The results showed that the high concentration of PVA significantly affected the weight and moisture content but did not affect the organoleptic thickness, folding endurance, and pH of the matrix patch. The best matrix patch of salam leaves ethanolic extract was PVA and AC of 3:1 because it met the requirements for the matrix patch, including the weight of 1.96-2.06 grams, thickness of 1.15-1.18 mm, folding endurance &gt;300 times, humidity 25.75 – 30.17% and pH 6.3 – 7.1. The patch contains flavonoids with Rf values for extract and patch of 0.95 and 0.96, respectively. Further study, in vivo anti-inflammatory test is necessary.

Analysis of Hydroquinone Compounds in Whitening Body Lotion Preparations Circulating in The Community

Skin care has become an important part for today's women. Whitening body lotion is very necessary in maintaining skin when doing activities outside and indoors. Many Indonesian women desire to have white, clean and bright skin so they can appear attractive. An attractive appearance is very necessary in society. To achieve this, many women choose skin care products at affordable prices without paying attention to the dangers of the chemical content in them. One of the skin whitening ingredients that is often used in beauty products is the compound hydroquinone. The hydroquinone compound plays a role in preventing skin pigmentation. However, if the levels exceed 0.02% in the preparation, it will cause skin irritation, kidney function disorders and cancer. The type of research is a mixed type, namely qualitative and quantitative. Qualitatively, it will obtain data on the presence of hydroquinone and quantitatively in the form of hydroquinone levels. The samples were 5 whitening body lotion preparations circulating in Lubuk Pakam which were determined randomly and were coded A, B, C, D, and E. Qualitative analysis was carried out using the TLC method and quantitative analysis was carried out using the UV-spectrophotometric method. Visible. The results of qualitative analysis show that samples A, C, and D contain hydroquinone compounds which are characterized by the appearance of blackish brown spots with respective Rf values of 0.89; 0.96; and 0.89. Meanwhile, when qualitative analysis was carried out, the levels obtained for the three samples were 44.56% each; 5,604%; and 5,612%. Based on regulations issued by BPOM RI in 2022, it is stated that hydroquinone levels in beauty products must not exceed 0.02%. So it can be concluded that whitening body lotion preparations with sample codes A, C, and D are not recommended for use because the use limit for hydroquinone is classified as unsafe. It is recommended that people, especially women, be more selective in choosing and using beauty products.

Formulation, Evaluation &amp; Comparative Study of Effects of Super Disintegrants in Herbal Fast Dissolving Tablet of Nyctanthes Arbor Tristis.

The purpose of this research work was to formulate &amp; evaluate the herbal fast dissolving tablet of Nyctanthes Arbor Tristis. Taxonomically, the plant was authenticated by the Padmashri vikhe patil college of Arts, Science, &amp; Commerce in pravaranagar. Ref.No./PVPC/Bot./2023-24/235. The aimed is to treat inflammation associated with Sciatica. A two independent variables of superdisintegrants are used such as crosspovidone &amp; croscarmellose sodium. Using DOE software, 32 full factorial design was used to examine the combined impact of two formulation variables. TLC was performed to identify the beta sitosterol with RF value of 0.77. to determine the physicochemical interaction between the drug &amp; the excipients, FTIR study was done. FTIR study revealed that there is no interaction of the drug and excipient. In this investigation, the tablets were formulated and assessed via direct compression. The powder mixture were compressed into tablet using single punch tablet machine. All the formulations were evaluated for their characteristic such as weight variation, hardness, thickness, friability, disintegration time(DT), and dissolution rate. It was determined from all evaluation parameter that the F9 batch was the optimized batch. It was found that an optimized batch (F9) has good cumulative drug release in 20 minutes (88.87%), DT of 56 seconds, and hardness of 2.923kg/cm2. The comparative studies are done with the marketed formulation. With the commercial formulation, the optimized batchF9 satisfies all standard specification.

Pressure and Its Impact on Job Satisfaction and Organizational Performance

This paper explores the complex idea of work pressure among Chinese hospital administrators and how it affects job happiness and overall effectiveness of the organization. Hospital directors confront a wide range of intricate issues within the framework of China's distinct healthcare system because of their twin responsibilities as administrative and medical leaders. The dimensions of role pressure are examined in this study, which include role gap, role overload, where the workload is excessive, role ambiguity, and the role of conflict. Understanding these aspects is essential to appreciating the effectiveness and well-being of hospital administration. Given that job happiness is a major factor in both employee performance and retention, these pressures have a significant effect on job satisfaction. The study also looks at the wider effects of pressure on organizational performance, which is crucial for the long-term viability and efficiency of healthcare facilities. Through an examination of these facets, the paper illuminates the noteworthy, albeit frequently disregarded, psychological and operational obstacles encountered by hospital administrators in China. This, in turn, offers valuable perspectives on the possibility of policy and administrative changes targeted at augmenting job contentment and organizational results

Examination of the Bactericidal and Fungicidal Activity of Bacillus amyloliquefaciens M Isolated from Spring Waters in Bulgaria

In order for a strain to be considered a probiotic or suitable plant bioprotective agent, it must have proven antimicrobial activity against pathogenic bacteria and phytopathogenic fungi. Bacillus amyloliquefaciens M exhibited significantly high antifungal activity against pathogenic fungi of the genera Aspergillus, Penicillium, Fusarium, and Sclerotinia; yeasts of the genera Candida and Saccharomyces; as well as high antibacterial activity against pathogens of the genera Escherichia, Salmonella, Staphylococcus, Listeria, Pseudomonas, and Bacillus. The manifested antimicrobial activity was influenced by the composition of the growth medium. The antifungal activity of the strain was investigated at growth temperatures of 30 °C and 37 °C, and at different pH values in aerobic and anaerobic cultivation, under static and dynamic culturing conditions. High antifungal activity was observed at the 24th h on both growth media (LBG broth and MPB broth) at pH = 6 and pH = 7 in aerobic and anaerobic cultivation. Bacillus amyloliquefaciens M produced antibiotic substances at pH &gt; 5.0, and the antibiotic substances were either secreted into the medium or associated with the cell surface. Four compounds with different antifungal activity and different Rf values were registered through thin-layer chromatography (Rf1 = 0.47; Rf2 = 0.55; Rf3 = 0.67; and Rf4 = 0.75), two of the compounds were ninhydrin-positive. Bacillus amyloliquefaciens M was cultured in a bioreactor with stirring, and the parameters of the growth kinetics and the sporulation kinetics have been modeled. A spore concentrate of Bacillus amyloliquefaciens M has been obtained. In further research, the efficiency of the concentrate as a plant bioactive agent will be tested.

Stability indicating high performance thin layer chromatography method development and validation for quantitative determination of tetracycline hydrochloride in tetracycline hydrochloride active pharmaceutical ingredient (API) and its dosage forms

Simple, quick, cost-effective, and environmentally friendly analytical methods for quality assurance and control roles for different medicines, including Tetrcyclines, are most significantly needed. Also, different thin layer chromatography (TLC)-based methods for tetracycline identification exist, but high performance thin layer chromatography methods based on modern state- of- the art equipment are still nonexistent. Thus, in this study, analytical method development and verification were done by high performance thin layer chromatography (HPTLC) (using an automated equipment model) using glass plates coated with silica gel 60 F254 after treating with 10% Na2EDTA. Validation was carried out according to International Council for Harmonization (ICH) guidelines. A mobile phase formed from ethyl acetate, acetonitrile, methanol, and 1% aqueous ammonia in the composition of 4.4:19.6:10:6 volume to volume ratio (V/V) was used. Rf value, percentage recoveries, linearity ranges, limit of detection (LOD), and limit of quantitation (LOQ) for the developed HPTLC method were 0.28, 100.83–106.25%, 160–560 ng/band (r2 values of 0.9999), 31.9 ng/band, and 96.7 ng/band, respectively. The results of the sample assays conducted using the new method and the United States Pharmacopoeia (USP) high performance liquid chromatography (HPLC) method were 91.59% to 108.3% and 90.83% to 102.85%, respectively. The F test for the aforementioned methods was 2.01, which is smaller than the tabulated F value of 5.05 with 5 degrees of freedom at a 95% confidence range, proving that the newly developed HPTLC and HPLC pharmacopoeial methods can be used interchangeably.The newly developed HPTLC method is easy, economical, specific, accurate, and roboust, thus it can be employed in a range of settings that require quality control and assurance activities of tetracycline hydrochloride (TC-HCl) in bulk and ointment dosage forms.

Physical insights into uranyl diffusion and sorption in bentonite: Theoretical and molecular dynamics study

Mechanistic understanding of diffusion and sorption of radionuclides and metals in clay-based engineered barriers is essential to develop models and define parameters for transport calculations for the safety analysis of disposal systems. Here we studied diffusion of uranyl (UO22+) species in the clay interparticle pore or macropores of bentonite clay by means of molecular dynamics simulation (MDS) for pore sizes ranging from 8.37 to 33.5 nm. The conceptual model of the clay pore system considered diffusion as a combination of pore diffusion (Dp) and surface diffusion DS (i.e. diffusion of adsorbed cations within the electrical double layer of the clay surfaces), from which the apparent diffusion Da was calculated as the weighted sum of Dp and DS, using a weighing factor f calculated as the ratio of adsorbed to total UO22+ in the system. Diffusivities at equilibrium for the largest pore size of 33.5 nm were: Da=7.37×10−10 m2 s−1, Dp=1.14×10−9 m2 s−1, and Ds=1.97×10−13 m2 s−1. The Ds was several orders of magnitude smaller than Dp. This was evident from the much smaller gradient of the mean-square displacement vs time lag curve for the adsorbed species than that of the species in the pore space. We found a remarkable consistency between our theoretical derivation and independent MDS evidence. For the slit-shaped interparticle pore, the retardation factor Rf was found to be the reciprocal of the unabsorbed fraction (Rf=1/1−f) and the capacity factor α was a ratio of the porosity to the unadsorbed fraction (α=ε1−f) or the ratio of the diffusant density in the bulk sample to the corresponding density in the pore solution. MD simulations of diffusion and sorption processes can be applied to other transport related problems at continuum scale, pore scale and molecular scale, such as for improved modelling of global elemental cycles, CO2 geosequestration, or the performance of desalination membranes.

Study on advection–dispersion behavior for simulation of 3H, 99Tc, and 90Sr transport in crushed sandstone of column experiments

Abstract In order to establish a universal and safety-compliant post-closure safety assessment technique, it is necessary to develop appropriate models to explain the migration behavior of radioactive materials within the rock system. Advection-dispersion experiments (ADE) have proven successful in designing transport models through a calibration/validation process of breakthrough curves (BTCs). In the present investigation, we employed a dynamic column device to examine the transport of Tritium (3H), Technetium-99 (99Tc), and Strontium-90 (90Sr) in crushed sandstone. Non-reactive transport experiments utilizing conservative tracers enabled us to determine the transport parameters, including retardation factors (R) and dispersivity (α). Our study focused on investigating the surface complexation model (SCM) using an additive approach coupled with the advection-dispersion equation to simulate the reactive transport behavior of 90Sr. The results affirm the robustness of our chosen thermodynamic database and modeling approach, emphasizing the criticality of accurately modeling and predicting reactive transport behavior in porous media.

Cytotoxic Potential of Berunok Sea Cucumber (Paracaudina australis) Against Breast Cancer Cells (T47D)

Background Sea cucumbers can be explored as alternative raw materials by the pharmaceutical and fishery industries as anticancer agents because they contain potential bioactive compounds. Methods This study aimed to determine the anticancer activity of Paracaudina australis extract against breast cancer cells (T47D) using an MTT assay. The secondary metabolites found in P.australis are steroids, terpenoids, saponins, and phenolics. The Thin-Layer Chromatography test results are indicated by Rf values, and steroid compounds in the ethyl acetate fraction are included in the standard Rf values. The isolates obtained were identified by Gas Chromatography-Mass Spectrometry, Fourier-Transform Infrared Spectroscopy, High-performance liquid chromatography, and UV-Visual spectrophotometry. Results The isolated compounds were Dihydrocholesterol and Cholestan-3-ol, with a molecular formula (C27H48O). The ion weight and molecular mass of the compound were m/z 388,7. Conclusions This compound may be responsible for the anticancer activity of P.australis. The IC50 of Isolate F4 was 25,3 μg/ml, and IC50 of Isolate F7,8 was 13,76 μg/ml.

Standardization and Phytochemical screening of Abutilon crispum

The main objective of the research is to recognize, validate and also to avoid the adulteration of plant Abutilon crispum. The correct identification of the plant Abutilon crispum was possible because of preliminary phytochemical screening, extraction by maceration and standardization. Preliminary phytochemical screening and TLC studies were carried out by standard methods with extracts such as chloroform, ethyl acetate and methanol. While standardization comprises the evaluation of parameters like pH range, water-soluble ash, loss on drying, total ash, acid insoluble ash, sulfated ash, ethanol-extractable parameters. The following values are found to be the results of the above testsi.e, loss on drying and total ash values are 7.2±0.22 and 6.32±0.04 correspondingly, water soluble ash was 1.33±0.05. Preliminary phytochemical evaluation for these extracts discovered the occurrence of flavonoids, steroids, terpenoids, glycosides and alkaloids in this plant. In methanol extract also major components such as alkaloids, flavonoids, tannins and glycosides were found. The thin layer chromatography examination of Abutilon crispum displayed the occurrence of steroids with0.76 and 0.52 Rf values in diverse solvent systems. TLC investigation of extract of ethyl acetate exhibited Rf values 0.74 and 0.81 due to occurrence of flavonoids with in dissimilar solvent systems similarly. The evidence found from contemporary study deliver valuable data that will be supportive in identifying and to perform upcoming research in future.