Multi-Objective Optimization of Process Parameters during Micro-Milling of Nickel-Based Alloy Inconel 718 Using Taguchi-Grey Relation Integrated Approach

This research investigates the machinability of Inconel 718 under conventional machining speeds using three different tool coatings in comparison with uncoated tool during milling operation. Cutting speed, feed rate and depth of cut were selected as variable machining parameters to analyze output responses including surface roughness, burr formation and tool wear. It was found that uncoated and AlTiN coated tools resulted in lower tool wear than nACo and TiSiN coated tools. On the other hand, TiSiN coated tools resulted in highest surface roughness and burr formation. Among the three machining parameters, feed was identified as the most influential parameter affecting burr formation. Grey relational analysis identified the most optimal experimental run with a speed of 14 m/min, feed of 1 μm/tooth, and depth of cut of 70 μm using an AlTiN coated tool. ANOVA of the regression model identified the tool coating parameter as most effective, with a contribution ratio of 41.64%, whereas cutting speed and depth of cut were found to have contribution ratios of 18.82% and 8.10%, respectively. Experimental run at response surface optimized conditions resulted in reduced surface roughness and tool wear by 18% and 20%, respectively.     

First-Principles Computational Study of the Modification Mechanism of Graphene/Graphene Oxide on Hydroxyapatite

Due to its unique crystal structure and nano-properties, hydroxyapatite (HA) has become an important inorganic material with broad development prospects in electrical materials, for fire resistance and insulation, and in bone repair. However, its application is limited to some extent because of its low strength, brittleness and other shortcomings. Graphene (G) and its derivative graphene oxide (GO) are well known for their excellent mechanical properties, and are widely used to modify HA by domestic and foreign scholars, who expect to achieve better reinforcement and toughening effects. However, the enhancement mechanism has not been made clear. Accordingly, in this study, G and GO were selected to modify HA using the first-principles calculation method to explore the theory of interfacial bonding of composites and explain the microscopic mechanism of interfacial bonding. First-principles calculation is a powerful tool used to solve experimental and theoretical problems and predict the structure and properties of new materials with precise control at the atomic level. Therefore, the bonding behaviors of hydroxyapatite (100), (110) and (111) crystal planes with G or GO were comprehensively and systematically studied using first-principles calculation; this included analyses of the density of states and differential charge density, and calculations of interfacial adhesion work and elastic moduli. Compared to HA (100) and (111) crystal planes, HA (110) had the best bonding performance with G and with GO, as revealed by the calculation results. The composite material systems of HA (110)/G and HA (110)/GO had the smallest density of states at the Fermi level, the largest charge transfers of Ca atoms, the largest interfacial adhesion work and the most outstanding elastic moduli. These results provide a theoretical basis for the modification of HA to a certain extent, and are beneficial to the expansion of the scope of its application.     

Interspecies Recombination-Led Speciation of a Novel Geminivirus in Pakistan

Recombination between isolates of different virus species has been known to be one of the sources of speciation. Weeds serve as mixing vessels for begomoviruses, infecting a wide range of economically important plants, thereby facilitating recombination. Chenopodium album is an economically important weed spread worldwide. Here, we present the molecular characterization of a novel recombinant begomovirus identified from C. album in Lahore, Pakistan. The complete DNA- A genome of the virus associated with the leaf distortion occurred in the infected C. album plants was cloned and sequenced. DNA sequence analysis showed that the nucleotide sequence of the virus shared 93% identity with those of the rose leaf curl virus and the duranta leaf curl virus. Interestingly, this newly identified virus is composed of open reading frames (ORFs) from different origins. Phylogenetic networks and complementary recombination detection methods revealed extensive recombination among the sequences. The infectious clone of the newly detected virus was found to be fully infectious in C. album and Nicotiana benthamiana as the viral DNA was successfully reconstituted from systemically infected tissues of inoculated plants, thus fulfilling Koch’s postulates. Our study reveals a new speciation of an emergent ssDNA plant virus associated with C. album through recombination and therefore, proposed the tentative name ‘Chenopodium leaf distortion virus’ (CLDV).     

The quality of telepsychiatry in terms of accessibility,appropriateness, effectiveness,and safety among psychiatric patients in King Abdulaziz Medical City: An observational cross-sectional analytical study

There has been an increasing demand for psychiatric care in recent decades, and “telepsychiatry” was developed to meet these demands. It is a type of telemedicine in which they provide many medical services virtually, such as therapy, counseling, and medication management. Telepsychiatry has numerous advantages, including lower costs, reduced stigma, and improved continuity of care. To the best of our knowledge, no previous studies in the western region of Saudi Arabia addressed patients satisfaction with telepsychiatry. This cross-sectional study aims to assess patient satisfaction in telepsychiatry in terms of accessibility and timeliness, appropriateness, effectiveness, and safety, and to see whether patient satisfaction affects their decision to use the service again in the future. A cross-sectional study was conducted using a prestructured survey on the basis of the Client Satisfaction Questionnaire-18, which is a validated questionnaire used to assess patients’ satisfaction with the services provided to them. From January 2021 to July 2021, all male and female psychiatric patients over the age of 18 years who had psychiatric virtual appointments were included in this study. This study included 182 patients, of whom 106 were female. Patients were generally satisfied with the telepsychiatry services; 56.6%, 81.9%, 86.8%, and 91.2% of the participants were satisfied with the access and timeliness, appropriateness, effectiveness, and safety, respectively, and a total of 58.3% either strongly agree or agree of the overall satisfaction level. Depression and anxiety disorders were the most common psychiatric diseases. The statistical analysis revealed no significant relationships between patients’ satisfaction and demographic characteristics. Telepsychiatry has been evaluated to meet the growing demand for psychiatric care; it also has significant advantages. Patients had an overall positive satisfaction level toward telepsychiatry service, and so the results of this study support the continuity of using telepsychiatry in the future. Further research area could include a comparison between patients’ and providers’ satisfaction levels with telepsychiatry.     

Management peculiarities of costovertebral hydatidosis

BackgroundCostovertebral hydatidosis is a rarely reported clinical and radiological entity, estimated at less than 1% of thoracic hydatid locations. Its management is still not codified.ObjectiveThe aim of our study was to specify the management peculiarities of costovertebral hydatidosis.MethodsBetween January 2000 and December 2018, 14 patients were managed for costovertebral hydatidosis in a thoracic surgery department.ResultsThe mean age of our patients was 48 years. The history of a prior hydatid disease was found in 7 patients. Imaging features were suggestive in 13 cases. They showed: involvement of the spinal canal (6 cases), of the soft tissues (5 cases) and spinal cord compression (3 cases). Costovertebral resection of the hydatid lesions was complete in 12 cases. Four patients presented postoperative complications.ConclusionCostovertebral hydatid involvement, may threaten the functional and vital prognosis. Therefore, early diagnosis and management are mandatory, before the occurrence of irreversible neurological impairment. Surgical resection remains the treatment of choice and must be complete whenever possible. Relapse is frequent, hence the importance of a regular follow-up.     

Epigallocatechin gallate ameliorates tetrahydrochloride-induced liver toxicity in rats via inhibition of TGFβ / p-ERK/p-Smad1/2 signaling,antioxidant, anti-inflammatory activity

Chronic liver disease is a worldwide health problem. Carbon tetra hydrochloride is an environmental toxin which is regarded as highly toxic and a potential human carcinogen. It can cause liver damage through the generation of metabolites and production of free radicals. Green tea contains catechins such as Epigallocatechin gallate which has been found to reduce the inflammation, oxidative stress, and fibrosis in experimental animal models. Hence, it represents a good source to prevent or ameliorate several chronic diseases. Silymarin is extracted from milk thistle seeds and has been found to be an effective agent to reduce the oxidative stress and free radical production and thereby exert protective effects in chronic liver conditions. The present study was planned to keep in view the above-mentioned facts. We included thirty rats in our study and divided them into five groups, each having six rats and the study continued for 8 weeks. Group I received normal saline; Group 2 received i.p. CCl4 injections; Group 3 received CCl4 i.p. injection and Epigallocatechin gallate (EGCG) oral gavage, Group 4 received CCl4 i.p. injection and silymarin by oral gavage; and Group 5 received CCl4 i.p. injection and combined EGCG + silymarin by oral gavage. The study found that in group 2, CCl4 induced significant elevation of ALT and MDA and reduced GSH thereby signifying increased oxidative stress. CCl4 also significantly increased inflammatory (TNFα, NFκB, IL1β, and TGFβ) as well as fibrotic markers (p-ERK and p-Smad1/2 protein expression). EGCG and silymarin significantly reversed the previously mentioned parameters either alone or in combination; however, the effect was more pronounced in case of EGCG. We conclude that EGCG and silymarin possess liver protective effects through their antioxidant, anti-inflammatory, and antifibrotic action.     

Photo fermentative biohydrogen production potential using microalgae–activated sludge co-digestion in a sequential flow batch reactor (SFBR)

Biohydrogen (bioH₂) is a sustainable energy source that can produce carbon-free energy upon combustion. BioH₂ can be generated from microalgae by photolytic and anaerobic digestion (AD) pathways. The AD pathway faces many challenges when scaling up using different bioreactors, particularly the continuous stirred tank reactor (CSTR) and sequential flow batch reactor (SFBR). Therefore, the performance characteristics of SFBR were analysed in this study using Chlorella vulgaris and domestic wastewater activated sludge (WWAS) co-culture. An organic loading rate (OLR) of 4.7 g COD L⁻¹ day⁻¹ was fed to the SFBR with a hydraulic retention time (HRT) of five days in the presence of light under anaerobic conditions. The pH of the medium was maintained at 6 using a pH controller for the incubation period of 15 days. The maximum bioH₂ concentrations of 421.1 μmol L⁻¹ and 56.6 μmol L⁻¹ were observed in the exponential and steady-state phases, respectively. The effluent had an unusually high amount of acetate of 16.6 g L⁻¹, which remained high with an average of 11.9 g L⁻¹ during the steady state phase. The amount of bioH₂ produced was found to be inadequate but consistent when operating the SFBR with a constant OLR. Because of the limitations in CSTR handling, operating a SFBR by optimizing OLR and HRT might be more feasible in operation for bioH₂ yield in upscaling. A logistic function model was also found to be the best fit for the experimental data for the prediction of bioH₂ generation using co-culture in the SFBR.

Biohydrogen (bioH₂) is a sustainable energy source that can produce carbon-free energy upon combustion.     

3,4,3′-Tri-O-methylellagic acid as an anticancer agent: in vitro and in silico studies

We report a natural product compound isolated from Syzygium polycephalum known as 3,4,3′-tri-O-methylellagic acid (T-EA) as a candidate drug for cancer treatment. The characterization of the isolated T-EA compound was carried out using various spectroscopic methods. The in vitro evaluation showcased the inhibition activity of T-EA towards the T47D and HeLa cell lines with EC₅₀ values of 55.35 ± 6.28 μg mL⁻¹ and 12.57 ± 2.22 μg mL⁻¹, respectively. Meanwhile, the in silico evaluation aimed to understand the interaction of T-EA with enzymes responsible for cancer regulation at the molecular level by targeting the hindrance of cyclin-dependent kinase 9 (CDK9) and sirtuin 1 (SIRT1) enzymes. T-EA showed a binding free energy towards the SIRT1 protein of ΔG_{bind (MM-GBSA)}: −30.98 ± 0.25 kcal mol⁻¹ and ΔG_{bind (MM-PBSA)}: −24.07 ± 0.30 kcal mol⁻¹, while that of CDK9 was ΔG_{bind (MM-GBSA)}: −29.50 ± 0.22 kcal mol⁻¹ and ΔG_{bind (MM-PBSA)}: −25.87 ± 0.40 kcal mol⁻¹. The obtained results from this research could be considered as important information on 3,4,3′-tri-O-methylellagic acid as a drug to treat cervical and breast cancers.

We report a natural product compound isolated from Syzygium polycephalum known as 3,4,3′-tri-O-methylellagic acid (T-EA) as a candidate drug for cancer treatment using in vitro and in silico approaches.