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A model for oil-in-water emulsion has been developed in this paper. A group of viscosity coefficients transiting smoothly and incessantly from the thick film region to the thin film region is defined. The contributions from disperse and continuous phases to the total lubricant pressure and pressure gradient are functions of the oil concentration and the film thickness. The parameters used in these functions are determined by a series of computational fluid dynamics simulations. The onset of inversion and the viscosity after inversion are also investigated. It is found that the critical volume fraction of oil in the inception of inversion is dependent on the oil viscosity and a factor regarding the combined effects from the emulsifier, pH value, droplet size, and the shear rate. A series of simulations using the proposed model has been carried out and compared with the experimental results, such as the film thickness and the extension of oil pool for various rolling speeds and supply oil concentrations. The numerical outputs are basically in agreement with the experiments. [DOI: 10.1115/1.4000274] Keywords: emulsion, phase inversion, effective viscosity, Reynolds equation, hydrodynamic lubrication

The influence of the minute elastic deformation of tool surface, named the 'microwedge,' on the asperity crushing in liquid lubrication is investigated experimentally. The microwedge plays a role so dominant that although increasing the average velocity of the lubricant can alleviate the asperity deformation: such efforts will be overwhelmed by the microwedge effect if the relative sliding velocity between tool and workpiece is also enhanced concurrently. For all roughness patterns, the asperities show multidirectional expansions of the contact region; an important feature of the microwedge effect. The microwedge effect also creates distributions of surface separation and hydrodynamic pressure neither expected nor explainable by the other models.

Based on real-time observation of the workpiece surface in a series of Lo and Tsai's (2002) compression-sliding experiment, it is found that the asperity contact area is much greater than that evaluated by the existing theorems such as the junction-growth theorem. With the aid of finite element analysis, it is verified that the tool sliding motion along with the minute elastic deformation (microwedge) of the tool surface around the asperity peaks increase the asperity contact area significantly even in a frictionless sliding. The microwedge induces a component of force along the sliding direction on the asperity. A combination of flattening and smearing effects can therefore aid in expanding the contact area. The greater the wedge angle, the stronger the propellent effect. An incremental model has also been developed to predict the evolution of contact area during sliding. The numerical simulation compares well with the experimental results. The new mechanism not only introduces an important tribological variable to forming processes but also brings in a new concept of surface quality control for processes having a considerable sliding distance between workpiece and tool such as ironing, forging, and extrusion. New processes performing high relative sliding velocity can therefore be developed to ameliorate the brightness of products. [DOI: 10.1115/1.1574518]

To study the evolution of asperity contact in the sliding contact, a new in situ observation system of sheet metal surface is built up. The workpiece is stationary so that the continuous deformation of a specific group of asperities can be traced. In the case of no strain rate in the substrate of workpiece, the experiments for various materials, roughness patterns, sliding velocities, and normal loads all show that the fractional contact area will increase from its initial state of pure flattening without shear stress, to a saturated value with sliding distance in different rates. The sliding velocity has minor influence on the variation of contact area for same sliding distance. The maximum increasing rate of the contact area is found in the case of medium load. In most cases, the increase in contact area takes place with simultaneously decreasing shear stress and pressure on the flattened asperity peak. The development of adhesive wear can be clearly observed in the case of high normal load and long sliding distance.

A model of a secondary hydrodynamic lubrication mechanism, which is called micro-pool or micro-plasto hydrodynamic lubrication has been developed. It shows that, with sufficiently high viscosity and sliding speed, the lubricant trapped in the micro-pools between the tool and workpiece can be drawn into the interface. The friction force is either increased or decreased, depending on the viscosity and sliding speed. Without bulk stretching, the product of the lubricant viscosity and sliding velocity can be used as an index to indicate whether or not micro-pool lubrication will occur. Stretching the workpiece may make a strong influence not only on the thickness of the permeating film but also on the asperity contact area.

The present 'realistic' friction model is examined by a series of upsetting tests. Specimens made of different aluminum alloys and prepared by various processes display diverse results. Severe surface roughening takes place in some cases using A6061T4 bar manufactured by hot extrusion. It results in a lubrication condition which is very different from the theoretical prediction. From hardness tests and microstructure observations, it is found that there is no obvious correlation between the hardness and the roughening process for A6061T4 alloy. The severe roughening is attributed to the distortion of the coarse grains recrystallized during the preprocess, that is, the hot extrusion. This is rare in sheet metal forming where most workpieces are prepared from cold rolled sheet metals. The orange peel appearance not only changes the lubrication mechanics, but also makes the surface finish of the product unacceptable. Since the existing friction model fails to predict such phenomena, surface roughening and all its related factors must be considered as new, important tribological variables in the friction modeling of bulk metal forming.

A theory employing the concept of potential flow and an easily implemented numerical method are developed. It can offer a preliminary prediction of the optimum blank shape with a little computational effort. The effects of the material anisotropy and the interfacial friction between the workpiece and blank holder on the material flow can be modeled by superimposing a 'sink' or 'source' term in the potential field. Variations in the cup wall thickness are considered. Both convex and non-convex punch profiles are studied. Generally speaking, the contours of the present theory are smoother than the solutions from the slip-line method. The discrepancy of the optimum blank contours between the plane strain and anisotropic cases is more significant for polygon and irregular cup drawing. The influence of friction on the optimum blank contour is not negligible.

A porous medium model is basically a macroscopic description of the fluid behavior and is considered more appropriate to the mixed lubrication regime. The present work has successfully combined the flow factor method, porous medium model and continuum percolation theory to investigate the flow phenomena in the mixed lubrication regime. Not only the lubricant flow can be solved but also the anisotropic percolation threshold can be obtained. Instead of the flow factor which is singular near h = 0, the lubricant flux itself is considered. A new definition of the pressure flow factor which is more appropriate to the mixed lubrication realm is suggested.

A passively compensated aerostatic thrust bearing of great static stiffness is proposed. It is composed of a silicone restrictor and a flexible metal disk supported circumferentially near the disk edge. The bent disk forms a concave bearing surface to hold the air pressure. The softer silicone capillary in the restrictor expands easily to adjust the air flux and the harder silicone layer at the restrictor bottom helps achieve higher inlet pressure. The Taguchi method showed that for bearing elevations between 8 and 10 μm, the optimal static stiffness can reach 538 N/μm, compared to 15 N/μm of the conventional type. The load capacity also levels up from 390 to 1,400 N at elevation of 8 μm. [ABSTRACT FROM PUBLISHER]

The evolution of the surface topography and tool-workpiece contact behavior of an aluminum sheet during plastic deformation has been investigated by a series of indentation tests for various loads, strain rates, and bulk strains. A simple formulation for estimating the roughness of the indented surface and a model of asperity flattening have been proposed. Dynamic balance between the flattening and roughening processes, such as changes of asperity angle and spacing, is considered. Theoretical predictions of the variation of real area of contact with strain show good agreement with experiments. It is found that the very different frictional behavior of aluminum compared with steel sheets is due to the serious change of roughness, including asperity angle and spacing. When the angle is small, the increases in asperity angle and spacing have strong effect on increasing the contact area ratio. However, when the asperity angle is large, increased asperity angle has a significant contribution to the resistance to flattening. The asperity flattening velocity and the increasing rate of contact area ratio arise with the prestrain; however, they are not affected by the strain rate significantly. From FFT analysis, low frequency components (below 10 cycle/mm) due to the rotation of single grains or grain groups are observed on free surface during plastic straining. While in the contact area, in all cases, the low frequency components generated by plastic deformation are compressed.

A commercial CFD code was used to analyze the effects of the rolling speed, oil viscosity, and supplying oil concentration on the pressure distributions of the oil and water phases, as well as the droplet movement and deformation. To simplify the calculations, the assumptions of isoviscous fluid and rigid surface were adopted and the film thickness was assigned. It was found that a more viscous oil phase enables the oil droplets to be drawn forwards easily. Phase inversion (W/O emulsion) occurs when the oil viscosity and the supplying oil concentration increase. However, phase inversion is not a necessary condition for generating significant pressure in the upstream region and the pressure can rise considerably in spite of low oil concentration close to the supplied value. All the simulations suggested that an accelerated increase in pressure happens when the film thickness is approximately equal to the original diameter of an oil droplet. The pressure of the disperse phase is greater than that of the continuous phase and the discrepancy may become significant. [ABSTRACT FROM AUTHOR]

Introduction: Although the relationships between personal factors and smoking abstinence are well-documented, institutional variation in smoking abstinence remains underexplored. This study investigates institutional variation in the six-month smoking abstinence prevalence among institutions participating in Taiwan's Second-Generation Tobacco Cessation Program (SGTCP) and examines institutional characteristics associated with smoking cessation success., Methods: The analysis included 304,757 pharmacotherapy and health education sessions from 160,336 participants who received smoking cessation services across 2420 institutions under the SGTCP between 2000 and June 2022. Institutional characteristics analyzed included type of institution, number of healthcare professionals, proportion of sessions with high utilization, and service volume. Binary logistic regression models with generalized estimation equations were used to assess associations with six-month smoking abstinence status., Results: Substantial institutional variation was observed in six-month smoking cessation success, with prevalence ranging from 0.0 % to 100.0 % (mean = 37.84 %, SD = 25.74 %). After adjusting for ecological and personal factors, regional hospitals demonstrated the highest adjusted odds ratio (aOR) for success at 1.202 (95 % confidence interval [CI] = 1.159-1.246). Higher session utilization was positively associated with better outcomes, while institutions with a greater number of participating healthcare professionals showed reduced aORs., Conclusions: Structural characteristics, such as healthcare setting type and resource availability, and process factors, including methodologies that enhance utilization, are critical determinants of the effectiveness of smoking cessation interventions., Competing Interests: Declaration of competing interest On behalf of all co-authors, I declare that none of the co-authors are have any conflict of interest involving in this study., (Copyright © 2024 Elsevier Inc. All rights reserved.)

In this case study we describe how Sydney Local Health District (SLHD) Disability Inclusion and Advice Service (DIAS) provided support to disability group homes during the COVID-19 Delta and Omicron waves. The study provides insights into group home providers' experience of supports implemented by SLHD and other stakeholders. A mixed method approach was undertaken that included analysing data from a database and electronic medical records and a survey of disability group home managers. DIAS developed a range of processes to support prevention, outbreak preparedness and response. This included developing a Disability Shared Living COVID-19 Pathway, engaging with group home providers through a fortnightly Community of Practice, assisting with improving vaccination status and procuring personal protective equipment. During an outbreak DIAS provided a 24h, 7days per week on call support, coordinated outbreak management team meetings and collaborated with several internal and external stakeholders. SLHD infection prevention and control nurses were recruited to undertake a process of reviewing outbreak management plans and providing support during an outbreak. Most disability providers (86%) reported that they felt very prepared to manage outbreaks at the time of the survey (August 2022) compared with the pre-Delta wave, for which 36% reported feeling 'not prepared'. The proportion who rated the support from the stakeholders as very supportive/supportive was as follows: SLHD (100%), NSW Health (64%), National Disability Insurance Agency (50%) and National Disability Insurance Scheme Quality & Safeguards Commission (37%). Our case study provides insights into the support that LHDs can provide to disability homes in response to future outbreaks.

Deoxynucleoside triphosphates (dNTPs) are crucial for the replication and maintenance of genomic information within cells. The balance of the dNTP pool involves several cellular enzymes, including dihydrofolate reductase (DHFR), ribonucleotide reductase (RNR), and SAM and HD domain-containing protein 1 (SAMHD1), among others. DHFR is vital for the de novo synthesis of purines and deoxythymidine monophosphate, which are necessary for DNA synthesis. SAMHD1, a ubiquitously expressed deoxynucleotide triphosphohydrolase, converts dNTPs into deoxynucleosides and inorganic triphosphates. This process counteracts the de novo dNTP synthesis primarily carried out by RNR and cellular deoxynucleoside kinases, which are most active during the S phase of the cell cycle. The intracellular levels of dNTPs can influence various viral infections. This review provides a concise summary of the interactions between different viruses and the genes involved in dNTP metabolism.

Most cancer cells reprogram their glucose metabolic pathway from oxidative phosphorylation to aerobic glycolysis for energy production. By reducing enzyme activity of pyruvate kinase M2 (PKM2), cancer cells attain a greater fraction of glycolytic metabolites for macromolecule synthesis needed for rapid proliferation. Here we demonstrate that hydrogen sulfide (H 2 S) destabilizes the PKM2 tetramer into monomer/dimer through sulfhydration at cysteines, notably at C326, leading to reduced PKM2 enzyme activity and increased PKM2-mediated transcriptional activation. Blocking PKM2 sulfhydration at C326 through amino acid mutation stabilizes the PKM2 tetramer and crystal structure further revealing the tetramer organization of PKM2-C326S. The PKM2-C326S mutant in cancer cells rewires glucose metabolism to mitochondrial respiration, significantly inhibiting tumor growth. In this work, we demonstrate that PKM2 sulfhydration by H 2 S inactivates PKM2 activity to promote tumorigenesis and inhibiting this process could be a potential therapeutic approach for targeting cancer metabolism., (© 2024. The Author(s).)

To examine how different features of corrective messages moderate individuals' attitudes toward misinformation on social media, a 2 (misinformation source credibility: high vs low) × 2 (corrective message source: algorithmic vs peer correction) × 2 (correction type: factual elaboration vs simple rebuttal) between-subjects experiment was conducted. To reduce perceived credibility and respondents' attitudes toward the misinformation, peer corrections were more effective than algorithmic corrections for misinformation from a source with lower credibility; for misinformation from a highly credible source, the superiority effect of peer corrections was still significant on perceived credibility but not on respondents' attitudes toward the misinformation. For the fact-checking tendency, we did not find a robust effect about how different features of corrective messages interacted. Our findings provide important insights into message design in combatting misinformation on social media.

Using the risk information seeking and processing model, this study examined how five personality traits-extraversion, neuroticism, conscientiousness, openness to experience, and agreeableness-influenced individuals' information-seeking behaviors and vaccination intentions. An online survey was administered by a reputable polling company commissioned by this study. The survey employed age, education, gender, and income as distinct strata for sampling, which resulted in 1100 valid questionnaires. The following five conclusions were drawn from the data analysis: (1) Of the five personality traits, two-extraversion and conscientiousness-exhibited a notable impact on individuals' information-seeking behaviors and vaccination intentions. Individuals with the remaining three personality traits-neuroticism, agreeableness, and openness to experience-demonstrate either passive or no information-seeking behaviors on COVID-19. (2) Conscientiousness was the only personality trait linked to increased awareness of COVID-19 characteristics. Moreover, conscientious individuals were inclined to avoid depending on ISNs to seek COVID-19 information and developed vaccination intentions. In contrast, individuals high in agreeableness heavily depended on ISNs for COVID-19 information to initiate information-seeking behaviors. Meanwhile, individuals high in extraversion relied on two variables-affective responses and ISNs-to begin their information-seeking behaviors. (3) Respondents' perceptions of COVID-19 characteristics and their affective responses did not positively influence their perceived information insufficiency directly; instead, both needed to be mediated by ISNs to initiate their information-seeking behaviors. (4) In contrast to the two variables-perceived COVID-19 characteristics and affective responses-this study found that ISNs regarding COVID-19 played a more substantial role in shaping respondents' information-seeking behaviors and vaccination intentions. (5) Unexpectedly, openness to experience was found to have no impact on information-seeking behaviors during the COVID-19 pandemic., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

A range of recombinant monoclonal antibodies (rMAbs) have found application in treating diverse diseases, spanning various cancers and immune system disorders. Chinese hamster ovary (CHO) cells have emerged as the predominant choice for producing these rMAbs due to their robustness, ease of transfection, and capacity for posttranslational modifications akin to those in human cells. Transient transfection and/or stable expression could be conducted to express rMAbs in CHO cells. To bolster the yield of rMAbs in CHO cells, a multitude of approaches have been developed, encompassing vector optimization, medium formulation, cultivation parameters, and cell engineering. This review succinctly outlines these methodologies when also addressing challenges encountered in the production process, such as issues with aggregation and fucosylation., Competing Interests: Dr. Shih-Yen Lo, an editorial board member at Tzu Chi Medical Journal, had no role in the peer review process or the decision to publish this article. The other authors declared no conflicts of interest in writing this paper., (Copyright: © 2024 Tzu Chi Medical Journal.)

Background: Frailty is an important determinant of health-care needs and outcomes for people in hospital., Objectives: To compare characteristics and predictive ability of a multidomain frailty index derived from routine health data (electronic frailty index-acute hospital; eFI-AH) with the hospital frailty risk score (HFRS)., Methods: This retrospective study included 6771 patients aged ≥75 years admitted to an Australian metropolitan tertiary referral hospital between October 2019 and September 2020. The eFI-AH and the HFRS were calculated for each patient and compared with respect to characteristics, agreement, association with age and ability to predict outcomes., Results: Median eFI-AH was 0.17 (range 0-0.66) whilst median HFRS was 3.2 (range 0-42.9). Moderate agreement was shown between the tools (Pearson's r 0.61). After adjusting for age and gender, both models had associations with long hospital stay, in-hospital mortality, unplanned all-cause readmission and fall-related readmission. Specifically, the eFI-AH had the strongest association with in-hospital mortality (adjusted odds ratio (aOR) 2.81, 95% confidence intervals (CI) 2.49-3.17), whilst the HFRS was most strongly associated with long hospital stay (aOR 1.20, 95% CI 1.18-1.21). Both tools predicted hospital stay >10 days with good discrimination and calibration., Conclusions: Although the eFI-AH and the HFRS did not consistently identify the same inpatients as frail, both were associated with adverse outcomes and they had comparable predictive ability for prolonged hospitalisation. These two constructs of frailty may have different implications for clinical practice and health service provision and planning., (© 2022 The Authors. Australasian Journal on Ageing published by John Wiley & Sons Australia, Ltd on behalf of AJA Inc’.)

Ribonucleotide reductases (RRs or RNRs) catalyze the reduction of the OH group on the 2nd carbon of ribose, reducing four ribonucleotides (NTPs) to the corresponding deoxyribonucleotides (dNTPs) to promote DNA synthesis. Large DNA viruses, such as herpesviruses and poxviruses, could benefit their replication through increasing dNTPs via expression of viral RRs. Little is known regarding the relationship between cellular RRs and RNA viruses. Mammalian RRs contain two subunits of ribonucleotide reductase M1 polypeptide (RRM1) and two subunits of ribonucleotide reductase M2 polypeptide (RRM2). In this study, expression of cellular RRMs, including RRM1 and RRM2, is found to be down-regulated in hepatitis C virus (HCV)-infected Huh7.5 cells and Huh7 cells with HCV subgenomic RNAs (HCVr). As expected, the NTP/dNTP ratio is elevated in HCVr cells. Compared with that of the control Huh7 cells with sh-scramble, the NTP/dNTP ratio of the RRM-knockdown cells is elevated. Knockdown of RRM1 or RRM2 increases HCV replication in HCV replicon cells. Moreover, inhibitors to RRMs, including Didox, Trimidox and hydroxyurea, enhance HCV replication. Among various HCV viral proteins, the NS5A and/or NS3/4A proteins suppress the expression of RRMs. When these are taken together, the results suggest that HCV down-regulates the expression of RRMs in cultured cells to promote its replication.

Background: The rates of guideline-directed medical therapy (GDMT) prescription for heart failure with reduced ejection fraction (HFrEF) in Asia remain sub-optimal. The primary objective of this study was to examine HFrEF polypill eligibility in the context of measured baseline prescription rates of individual components of GDMT among participants with HFrEF in Asia., Methods: A retrospective analysis of 4,868 patients with HFrEF from the multi-national ASIAN-HF registry was performed, and 3,716 patients were included in the final, complete case analysis. Eligibility for a HFrEF polypill, upon which patients were grouped and characterized, was based on the following: left ventricular systolic dysfunction (LVEF < 40% on baseline echocardiography), systolic blood pressure ≥ 100 mm Hg, heart rate ≥ 50 beats/minute, eGFR ≥ 30 mL/min/1.73 m, and serum potassium ≤ 5.0 mEq/L. Regression analyses were performed to evaluate associations of the baseline sociodemographic factors with HFrEF polypill eligibility., Results: Among 3,716 patients with HFrEF in the ASIAN-HF registry, 70.3% were eligible for a HFrEF polypill. HFrEF polypill eligibility was significantly higher than baseline rates of triple therapy prescription of GDMT across sex, all studied geographical regions, and income levels. Patients were more likely to be eligible for a HFrEF polypill if they were younger and male, with higher BMI and systolic blood pressure, and less likely to be eligible if they were from Japan and Thailand., Conclusion: The majority of patients with HFrEF in ASIAN-HF were eligible for a HFrEF polypill and were not receiving conventional triple therapy. HFrEF polypills may be a feasible and scalable implementation strategy to help close the treatment gap among patients with HFrEF in Asia., Competing Interests: AA and MDH have a pending patent for heart failure with reduced ejection fraction polypills. AA is funded by an NIH award (K99HL157687-01A1) to evaluate a HFrEF polypill implementation strategy in South Asia., (Copyright: © 2023 The Author(s).)