Failure Factors Research Articles

Independent risk factors of left ventricular hypertrophy in non-diabetic individuals in Sierra Leone - a cross-sectional study

BackgroundLeft ventricular hypertrophy (LVH) is a critical factor in heart failure and cardiovascular event-related mortality. While the prevalence of LVH in diabetic patients is well-documented, its occurrence and risk factors in non-diabetic populations remain largely unexplored. This study addresses this issue by investigating the independent risk factors of LVH in non-diabetic individuals.MethodsThis cross-sectional study, conducted meticulously, utilized data from a robust and comprehensive source, DATADRYAD, in the Sierra Leone database, collected between October 2019 and October 2021, including LVH and various variables. All variables were described and screened using univariate analysis, Spearman correlation, and principal component analysis (PCA). The lipid profile, including total cholesterols (TC), triglycerides (TG), high-density lipoprotein (HDL-C), non-high-density lipoprotein (Non-HDL-C), and low-density lipoprotein cholesterol (LDL-C), TC/HDL-C ratio, TG/HDL-C ratio, Non-HDL-C /HDL-C ratio and LDL-C/HDL-C ratio, which quartiles were treated as categorical variables, with the lowest quartile serving as the reference category. Three adjusted models were constructed to mitigate the influence of other variables. To ensure the robustness of the model, receiver operating characteristic (ROC) curves were used to calculate the cutoff values by analyzing the ROC curves. A sensitivity analysis was performed to validate the findings further.ResultsThe dataset encompasses information from 2092 individuals. After adjusting for potential factors that could influence the results, we found that TC (OR = 2.773, 95%CI: 1.805–4.26), Non-HDL-C (OR = 2.74, 95%CI: 1.7723–4.236), TC/HDL-C ratio (OR = 2.237, 95%CI: 1.445–3.463), Non-HDL-C/HDL-C ratio (OR = 2.357, 95%CI: 1.548–3.588), TG/HDL-C ratio (OR = 1.513, 95%CI: 1.02–2.245) acts as independent risk factors of LVH. ROC curve analysis revealed the predictive ability of blood lipids for LVH, with Non-HDL-C exhibiting area under the curve (AUC = 0.6109), followed by TC (AUC = 0.6084).ConclusionsTC, non-HDL-C, TC/HDL-C ratio, Non-HDL-C/HDL-C ratio, and TG/HDL-C ratio were independent risk factors of LVH in non-diabetic people. Non-HDL-C and TC were found to be essential indicators for predicting the prevalence of LVH.

Importance of optical coherence tomography raster scans in early detection of active fellow-eye neovascularization in unilateral neovascular age-related macular degeneration

PurposeTo investigate the incidence of and risk factors for failure of detection of active fellow-eye neovascularization on optical coherence tomography(OCT) crosshair scans in patients with unilateral neovascular age-related macular degeneration(AMD).MethodsIn this retrospective study, patients who experienced the development of active neovascularization in the fellow eye during the follow-up period were included(n = 75). Cases in which the neovascularization in the fellow eye could be identified solely through crosshair scans were defined as the crosshair scan detection group(n = 63). Cases in which the aforementioned findings could not be identified through crosshair scans but could be identified through raster scans were defined as the raster scan detection group(n = 12). The factors were compared between the two groups. Risk factors related to undetected neovascularization on crosshair scans were additionally identified.ResultsActive fellow-eye neovascularization, was not detected on OCT crosshair scans in 12 cases(16.0%) but was identified on raster scans in all cases. There was a significant difference in the proportion of neovascularization types between the crosshair scan detection group and the raster scan detection group(P = 0.023). Among the 35 fellow-eye neovascularization cases in patients with type 3 macular neovascularization(MNV), 10(28.6%) were not detected on crosshair scans. Multivariate analysis revealed a significantly higher risk for undetectable fellow-eye neovascularization on crosshair scans in patients with type 3 MNV than in those with typical neovascular AMD(P = 0.037,β = 9.600).ConclusionsOur findings suggest the need for routine OCT raster scans during fellow-eye examinations in patients with unilateral neovascular AMD, particularly when the first-affected eye is diagnosed with type 3 MNV.

Research on Correlation Mining of Compressor Failure Factors based on Apriori Algorithm

Research on Correlation Mining of Compressor Failure Factors based on Apriori Algorithm

A study on critical failure factors for implementation of sustainable Lean Six Sigma from Indian manufacturing industries perspective using BWM technique

A study on critical failure factors for implementation of sustainable Lean Six Sigma from Indian manufacturing industries perspective using BWM technique

Time-Varying Reliability Analysis of Mechanisms with Strength Degradation Considering Clearances and Local Stiffness Effects

Mechanism systems are important components of dynamic mechanical systems. The time-varying reliability assessment of mechanism systems is of great significance for the safety and fault diagnosis of mechanical products. In this paper, a time-varying reliability evaluation method for mechanisms under the fatigue failure mode is proposed, which takes into account the joint effects of clearance, local structural stiffness, random load and random strength degradation. The proposed mechanism reliability models are established by nonlinear dynamic analysis considering failure factors and establishing random stress history characterization matrices. Additionally, the models are validated by the Monte Carlo simulation method. The results show that the mechanism clearance, local stiffness, and initial strength dispersion have a significant effect on the time-varying reliability of the mechanisms. Furthermore, both local stiffness and initial strength dispersion have a greater influence on the effect of clearance on the time-varying reliability of the mechanisms. The proposed reliability models can quantitatively analyze the dynamic effects of failure factors on the reliability of the mechanisms, which can be used for the stochastic remaining life evaluation and fault diagnosis of the mechanism systems.

The crucial relationship between vancomycin minimum inhibitory concentration and therapeutic efficacy against methicillin-resistant coagulase-negative staphylococci

The area under the curve (AUC)/minimum inhibitory concentration (MIC) ratio was used as an indicator of the clinical efficacy of vancomycin. However, the target AUC/MIC has not been set for methicillin-resistant coagulase-negative staphylococci (MR-CNS), and the effectiveness of vancomycin in strains with high MIC is unknown. Therefore, we aimed to investigate the relationship between the vancomycin MIC and therapeutic efficacy in patients with MR-CNS bacteremia. The primary outcome was the difference in treatment failure rate when the MR-CNS vancomycin MIC was 1 or 2 µg/mL. The treatment failure rate did not significantly differ between the two groups (MIC 1 vs. MIC 2: 27.0% vs. 31.0%; p = 0.779). As a result of multivariate analysis, AUC/MIC0–24 h ≤230 was extracted as risk factor for treatment failure, suggesting the importance of a sufficient initial loading dose and early blood concentration monitoring to increase AUC/MIC0–24 h for successful treatment.

Advancing the analysis of water pipe failures: a probabilistic framework for identifying significant factors

The failure of water pipes in Water Distribution Networks (WDNs) is associated with environmental, economic, and social consequences. It is essential to mitigate these failures by analyzing the historical data of WDNs. The extant literature regarding water pipe failure analysis is limited by the absence of a systematic selection of significant factors influencing water pipe failure and eliminating the bias associated with the frequency distribution of the historical data. Hence, this study presents a new framework to address the existing limitations. The framework consists of two algorithms for categorical and numerical factors influencing pipe failure. The algorithms are employed to check the relevance between the pipe’s failure and frequency distributions in order to select the most significant factors. The framework is applied to Hong Kong WDN, selecting 10 out of 21 as significant factors influencing water pipe failure. The likelihood feature method and Bayes’ theorem are applied to estimate failure probability due to the pipe materials and the factors. The results indicate that galvanized iron and polyethylene pipes are the most susceptible to failure in the WDN. The proposed framework enables decision-makers in the water infrastructure industry to effectively prioritize their networks’ most significant failure factors and allocate resources accordingly.

Failure factors of building construction projects in Ethiopia

Construction projects encounter considerable failure, and the case is worse in developing countries. Improving this situation needs an understanding of the failure factors; hence, this study is aimed at identifying critical failure factors of building construction projects in the Ethiopian construction industry. Sixty-four project failure attributes were identified through a literature review and categorized under eight groups of sources. Using a questionnaire survey, one hundred seven valid responses were collected from professionals affiliated with contractors, consultants, clients and regulatory bodies. For the analysis, factor analysis was conducted to identify the underlying dimensions of each group, and multiple regression analysis was conducted to identify critical failure factors. The findings indicate that: (i) unfavourable socio-economic and climatic conditions; (ii) owners’ incompetence, change orders and bureaucracy in public clients; (iii) political interferences and inflation; (iv) contractors’ incompetence; (v) progress payment, defective works, and staff quality challenges; and (vi) poor productivity, shortage of labour and escalation of material costs are the critical project failure factors in the context of the Ethiopian construction industry. These critical failure factors emanate from four group of sources: client, contractor, project input, and project external environment. The stakeholders need to devise appropriate strategies to mitigate these critical failure factors to ensure project success.

P79. Preoperative opioid use and anxiety are independent risk factors for failure to respond to erector spinae plane block in minimally invasive transforaminal lumbar interbody fusion

P79. Preoperative opioid use and anxiety are independent risk factors for failure to respond to erector spinae plane block in minimally invasive transforaminal lumbar interbody fusion

Bile Duct Injuries after Cholecystectomy: An Individual Patient Data Systematic Review.

Background: Post-cholecystectomy bile duct injuries (BDIs) represent a challenging complication, with negative impacts on clinical outcomes. Several surgical and endoscopic/interventional radiologist (IR) approaches have been proposed to manage these damages, though with high failure rates. This individual patient data (IPD) systematic review analyzes the potential risk factors for failure after treatment interventions for BDIs, both surgical and endoscopic/IR. Methods: An extensive literature search was conducted on MEDLINE and Scopus for relevant articles published in English on the management of BDIs after cholecystectomy, between 1 January 2010 and 31 December 2023. Our series of BDIs was included. BDIs were always categorized according to the Strasberg's classification. The composite primary endpoints evaluated were the failure of treatment interventions, defined as patient death or the requirement of any other procedure, whatever surgical and/or endoscopic/IR, after the primary treatment. Results: A total of 342 cases were retrieved from our literature analysis, including our series of 19 patients. Among these, three groups were identified: "upfront surgery", "upfront endoscopy and/or IR" and "no upfront treatment", consisting of 224, 109 and 9 patients, respectively. After eliminating the third group, treatment intervention failure was observed overall in 34.2% (114/333) of patients, of whom 80.7% (92/114) and 19.3% (22/114) in the "upfront surgery" and in the "upfront endoscopy/IR" groups, respectively. At multivariable analysis, injury type D and E, and repair in a non-specialized center represented independent predictors of treatment failure in both groups, whereas laparoscopic cholecystectomy (LC) converted to open and immediate attempt of surgical repair exclusively in the first group. Conclusions: Significant treatment failure rates are responsible for remarkable negative effects on immediate and longer-term clinical outcomes of post-cholecystectomy BDIs. Understanding the important risk factors for this outcome may better guide the most appropriate therapeutical approach and improve clinical decisions in case this serious complication occurs.

Ultrasound evaluation of cardiac and diaphragmatic function at different positions during a spontaneous breathing trial predicting extubation outcomes: a retrospective cohort study

BackgroundThe ratio (E/Ea) of mitral Doppler inflow velocity to annular tissue Doppler wave velocity by transthoracic echocardiography and diaphragmatic excursion (DE) by diaphragm ultrasound have been confirmed to predict extubation outcomes. However, few studies focused on the predicting value of E/Ea and DE at different positions during a spontaneous breathing trial (SBT), as well as the effects of △E/Ea and △DE (changes in E/Ea and DE during a SBT).MethodsThis study was a reanalysis of the data of 60 difficult-to-wean patients in a previous study published in 2017. All eligible participants were organized into respiratory failure (RF) group and extubation success (ES) group within 48 h after extubation, or re-intubation (RI) group and non-intubation (NI) group within 1 week after extubation. The risk factors for respiratory failure and re-intubation including E/Ea and △E/Ea, DE and △DE at different positions were analyzed by multivariate logistic regression, respectively. The receiver operating characteristic (ROC) curves of E/Ea (septal, lateral, average) and DE (right, left, average) were compared with each other, respectively.ResultsOf the 60 patients, 29 cases developed respiratory failure within 48 h, and 14 of those cases required re-intubation within 1 week. Multivariate logistic regression showed that E/Ea were all associated with respiratory failure, while only DE (right) and DE (average) after SBT were related to re-intubation. There were no statistic differences among the ROC curves of E/Ea at different positions, nor between the ROC curves of DE. No statistical differences were shown in △E/Ea between RF and ES groups, while △DE (average) was remarkably higher in NI group than that in RI group. However, multivariate logistic regression analysis showed that △DE (average) was not associated with re-intubation.ConclusionsE/Ea at different positions during a SBT could predict postextubation respiratory failure with no statistical differences among them. Likewise, only DE (right) and DE (average) after SBT might predict re-intubation with no statistical differences between each other.

Association of UGT1A Gene Polymorphisms with BKV Infection in Renal Transplantation Recipients.

BK virus (BKV) infection is an opportunistic infectious complication and constitutes a risk factor for premature graft failure in kidney transplantation. Our research aimed to identify associations and assess the impact of single-nucleotide polymorphisms (SNPs) on metabolism-related genes in patients who have undergone kidney transplantation with BKV infection. The DNA samples of 200 eligible kidney transplant recipients from our center, meeting the inclusion criteria, have been collected and extracted. Next-generation sequencing was used to genotype SNPs on metabolism-associated genes (CYP3A4/5/7, UGT1A4/7/8/9, UGT2B7). A general linear model (GLM) was used to identify and eliminate confounding factors that may influence the outcome events. Multiple inheritance models and haplotype analyses were utilized to identify variation loci associated with infection caused by BKV and ascertain haplotypes, respectively. A total of 141 SNPs located on metabolism-related genes were identified. After Hardy-Weinberg equilibrium (HWE) and minor allele frequency (MAF) analysis, 21 tagger SNPs were selected for further association analysis. Based on GLM results, no confounding factor was significant in predicting the incidence of BK polyomavirus-associated infection. Then, multiple inheritance model analyses revealed that the risk of BKV infection was significantly associated with rs3732218 and rs4556969. Finally, we detect significant associations between haplotype T-A-C of block 2 (rs4556969, rs3732218, rs12468274) and infection caused by BKV (P = 0.0004). We found that genetic variants in the UGT1A gene confer BKV infection susceptibility after kidney transplantation.

Connective tissue disorder is a risk factor for ileoanal pouch failure: A case-control study

IntroductionIleal-pouch anal anastomosis (IPAA) is a widely preferred surgical intervention in patients with medically refractory ulcerative colitis, familial adenomatous polyposis, and indeterminate colitis. Concerns have been raised regarding the impact of connective tissue disorders on the outcomes of IPAA owing to potential alterations in collagen metabolism. To date, there is a lack of studies assessing the feasibility, long-term viability, and pouch function of IPAA in patients with connective tissue disorders. We hypothesized that the presence of a connective tissue disorder was associated with an increased risk of pouch failure. MethodsData were collected from a prospectively maintained pouch database and chart review. Patients with connective tissue disorders were propensity score matched in a 1:5 ratio with control pouch patients without connective tissue disorders. A comparative analysis of the demographics, long-term complications, functional outcomes, and QoL was conducted. ResultsNineteen patients with connective tissue disorders were matched with 95 control pouch patients. Postoperative diagnoses included ulcerative colitis (82.5%), indeterminate colitis (7%), constipation (5.3%), Crohn's disease (4.4%), and familial adenomatous polyposis (1%). The connective tissue disorders identified included unspecified diffuse connective tissue disorders (26.3%), Ehlers-Danlos syndrome (15.7%), Sjögren's syndrome (15.7%), and others (31.2%). Patients with connective tissue disorders were more likely to have pouch leaks (OR 4.8, 95% CI: 1.54,15, p=0.007), pouchitis (OR 3.02, 95% CI: 1.09, 8.37, p=0.034), pouch revisions (OR 3.83, 95% CI: 1.31,11.2, p=0.014), and pouch failure (OR 3.55, 95% CI: 1.25, 10.1, p=0.017). When questioned, patients with connective tissue diseases were more likely to have work restrictions (OR 4.68, 95% CI: 0.74, 6.38, p=0.005) and a worse quality of life (std. estimate -0.15, 95% CI: -0.28,-0.19, p=0.025). ConclusionPatients with connective tissue diseases are more likely to be affected by pouch-related complications and pouch failure and report worse quality of life. Physicians treating patients with these disorders should counsel patients appropriately and be aware of the elevated risks of leaks, pouchitis, and pouch failure.

How to Prevent Local Recurrence of Sacral Chordoma Treated with Carbon-Ion Radiotherapy: An Analysis of the Risk Factors of Local Failure and an Adequate Disease Margin.

Recent reports have described the usefulness of carbon ion radiotherapy (CIRT) for inoperable sacral chordomas. However, its long-term local control rate needs to be improved. The present study identified the risk factors that affect the local relapse of sacral chordomas and the appropriate margins from the tumors. Forty-nine patients with sacral chordoma treated with CIRT between 2011 and 2022 were retrospectively analyzed. Factors predicting the risk of local recurrence were evaluated, including age, sex, tumor size, muscle invaded with tumor, and surgery before CIRT. To determine the appropriate margin, the distance between the clinical target volume (CTV) and the out-field recurrent lesions was analyzed. The patients included 37 males and 12 females with a mean age of 67.1 years. A multivariate analysis showed that a tumor size >8 cm and invasion into the gluteus maximus muscle were significant risk factors with hazard ratios of 5.56 and 15.20 (p = 0.02 and 0.01), respectively. Out-field recurrence occurred in 13 cases, with 6, 3, and 4 relapses occurring in the muscle, bone, and both, respectively. The tumor occurred within 20 mm from the CTV in 60% of relapses in the muscles. The current study presented novel findings on CIRT for sacral chordomas, although there were several limitations, such as a short follow-up period to investigate slow-growth tumors and a small number of tumor specimens owing to inoperative cases. A tumor size >8 cm and invasion into the gluteus maximus muscle were shown to be risk factors for recurrence in the treatment of sacral chordoma with CIRT. Our findings further suggest that an additional 2-cm margin from the CTV in the muscle fiber direction is recommended during CIRT.

Risk Factors of Pregnancy Failure in Infertile Patients Undergoing Assisted Reproductive Technology

Background: Assisted Reproductive Technology (ART) represents a critical advancement in the treatment of infertility, providing hope to many couples struggling to conceive naturally. Despite its success, pregnancy failure remains a significant concern, influenced by various factors such as age, BMI, and underlying medical conditions. Objective: The main objective of this study was to identify the risk factors associated with pregnancy failure in infertile patients undergoing ART treatments. Methods: This clinical audit was conducted at Bahria International Hospital, Rawalpindi, from January 2023 to January 2024. Data were collected from 85 patients undergoing ART treatments, including In Vitro Fertilization (IVF) and Intracytoplasmic Sperm Injection (ICSI). The study included comprehensive demographic information, clinical history, ART cycle details, laboratory results, and lifestyle factors. Pregnancy failure was defined as either biochemical pregnancy loss or clinical pregnancy loss. Ethical approval was obtained, and data were analyzed using SPSS version 25. Descriptive statistics summarized patient characteristics, while comparative analysis and multivariate logistic regression were used to identify significant risk factors. Results: The study included 85 patients with a mean age of 34.5 years. Those experiencing pregnancy failure had a higher mean age of 36.2 years compared to 33.2 years in those without pregnancy failure. The mean BMI was higher in the pregnancy failure group (26.0 kg/m²) versus the no pregnancy failure group (23.8 kg/m²). Significant risk factors for pregnancy failure included older age (OR=1.15, 95% CI 1.05-1.25, p=0.002), higher BMI (>25 kg/m²) (OR=2.45, 95% CI 1.10-5.47, p=0.03), and the presence of underlying medical conditions (OR=1.90, 95% CI 1.02-3.55, p=0.04). Conclusion: Older age, higher BMI, and underlying medical conditions significantly increased the risk of pregnancy failure in infertile patients undergoing ART. Personalized treatment approaches addressing these risk factors could improve ART outcomes and enhance the chances of successful pregnancies.

Internationalization of Companies: a Systematic Literature Review Supported by Bibliometric Analysis

Objective: Conduct a comprehensive analysis of the internationalization of companies (IE) over the past three decades, exploring topics ranging from alliance strategies to mergers and acquisitions (M&A). Theoretical Framework: Over the past decades, the study of internationalization has gained importance with the reduction of border barriers. Hamel (1991) highlighted the role of international strategic alliances in promoting competition and learning. Multinational companies from emerging markets have become relevant, and early international expansion has driven competitiveness and innovation. Method: The methodology combines Systematic Literature Review (SLR) and Bibliometric Analysis (BA), using VOSviewer 1.6.20 software to explore networks of co-authorship, co-citation, and co-occurrence in 246 articles published between 1991 and 2023. Results and Discussion: The results revealed challenges in internationalization, such as selecting suitable partners and mitigating risks. Understanding the factors of success or failure is crucial. Opportunities include consistent product strategies that enhance global competitiveness and strategic collaborations, such as international alliances and joint ventures, which promote learning and innovation. Organizational learning offers a sustainable competitive advantage. Implications of the Research: The practical and theoretical implications discussed provide insights into how the results may influence practices in the field of alliances within a globalized business environment. Originality/Value: This study adopts an interdisciplinary approach, highlighting the importance of contextual, cultural, institutional, and economic factors in understanding the complexities of international strategic alliances.

Literature Study: Building Adolescent Mental Health by Tackling Toxic Culture Among Teens on Social Media

Today's teenagers are active social media users. However, in interacting on social media, people often engage in negative behaviour on social media or toxic culture, which can interfere with adolescent mental health. If allowed to continue, it will be dangerous for the next generation. A toxic culture will cause moral decline in a nation, which will have an impact on the mental health of the community itself. Therefore, this study aims to provide a deeper understanding of how toxic culture on social media impacts the mental health of adolescents. This research uses a qualitative approach with a literature research method. Data analysis in this research uses the content analysis method of the literature that has been collected. The results showed that toxic culture on social media has a significant impact on adolescents' mental health. Forms of toxic culture that are often found on social media are body shaming, cyberbullying, addiction, and the spread of misinformation. It can have an impact on mental health, interpersonal relationships, and academic achievement and encourage risky behavior among adolescents. Therefore, efforts have been made to educate and improve digital literacy, parental guidance and supervision, content moderation, mental support, and community collaboration. These efforts have shown some degree of success. Factors influencing success include commitment and consistency from those involved, active involvement of parents, effective digital content moderation, adequate mental support, and strong community collaboration. However, there are failure factors such as lack of resources and funding, stigma and discrimination towards mental health issues, lack of coordination between stakeholders, resistance to change, and socio-cultural and economic factors.

Diagnostic and therapeutic challenges for PCPs regarding heart failure with preserved ejection fraction and obesity: results of an online internet-based survey

BackgroundObesity (body mass index ≥ 30 kg/m2) is a major risk factor for heart failure with preserved ejection fraction (HFpEF) and affects most patients with HFpEF. Patients living with obesity may experience delays in HFpEF diagnosis and management. We aimed to understand the clinical journey of patients with obesity and HFpEF and the role of primary care providers (PCPs) in diagnosing and managing patients with both conditions.MethodsAn anonymous, US population-based online survey was conducted in September 2020 among 114 patients with self-reported HFpEF and obesity and 200 healthcare providers, 61 of whom were PCPs who treat patients with HFpEF and obesity.ResultsHalf of patients (51%) with HFpEF reported waiting an average of 11 months to discuss their symptoms with a PCP; 11% then received their diagnosis from a PCP. PCPs initiated treatment and oversaw the management of HFpEF only 35% of the time, and 44% of PCPs discussed obesity treatment medication options with their patients. Only 20% of PCPs indicated they had received formal obesity management training, and 79% of PCPs indicated they would be interested in obesity management training and support.ConclusionPCPs could play a valuable role in addressing obesity and referring patients with obesity and signs and symptoms of HFpEF to cardiologists. Increased awareness of HFpEF and its link to obesity may help PCPs more quickly identify and diagnose their patients with these conditions.Graphical

Tribological behavior of Fe40Mn20Cr20Ni20 HEA sliding against various counterface materials

Wear is a failure factor that must be considered when alloys are in service, especially as moving parts. However, few current studies have addressed the tribological behavior of HEAs in service with tribo-pair systems consisting of materials in contact with them. Therefore, in this work, the tribological properties between Fe40Mn20Cr20Ni20 HEA with four typical counterfaces consisting of tribo-pair systems were investigated at room temperature, i.e., hard alloy (WC/Co), metal (GCr15 steel), ceramic (Si3N4) and plastic (POM). It was found that there were significant differences in the wear mechanisms between various tribo-pair systems. Moreover, adhesive wear dominates the wear extent of the alloys. The wear rate of the alloy after sliding with WC/Co or GCr15 even reached 20–30 times higher than that after sliding with Si3N4, indicating that the sliding contact of the alloy with WC/Co or GCr15 is not an optimal design during service. In addition, the frictional oxidation that occurs during sliding contact played good lubrication role. In tribo-pair systems consisting of Fe40Mn20Cr20Ni20 HEA with WC/Co, GCr15 or Si3N4, the average coefficient of friction exhibited a tendency to decrease with the normal force.

Risk factors for vancomycin treatment failure in heterogeneous vancomycin-intermediate Staphylococcus aureus bacteremia.

The incidence of heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) infection is increasing and is associated with vancomycin treatment failures. However, studies investigating the risk factors for treatment failure in hVISA infection are limited. Patients with hVISA bacteremia treated with vancomycin over 7 days between August 2008 and June 2020 were enrolled in this study. Clinical and microbiological characteristics were compared between vancomycin treatment failure and success groups to identify the risk factors for vancomycin treatment failure. Among the 180 patients with hVISA bacteremia, 102 patients treated with vancomycin over 7 days were included. Vancomycin treatment failed in 80 (78%) patients. Patients in the vancomycin treatment failure group were older (P < 0.001) and more frequently had solid cancer (P = 0.04) than those in the vancomycin treatment success group. Solid organ transplantation (SOT) was more frequent (P < 0.001) in the vancomycin treatment success group. The Charlson comorbidity index (P = 0.01) and Acute Physiology and Chronic Health Evaluation II scores (P < 0.001) were higher in the vancomycin treatment failure group. In multivariate analysis, independent risk factors for vancomycin treatment failure were old age and severity of bacteremia. SOT and vancomycin minimal inhibitory concentration (MIC) ≤ 1.0 mg/L using the broth microdilution (BMD) method were associated with successful vancomycin treatment. Old age and infection severity were independent risk factors for vancomycin treatment failure. Vancomycin MIC using the BMD method is an important risk factor for vancomycin treatment failure, and its use should be considered in hVISA bacteremia.IMPORTANCEIn this study, we assessed the clinical and microbiological characteristics of heterogeneous vancomycin-intermediated Staphylococcus aureus (hVISA) bacteremia and identified risk factors for vancomycin treatment failure. We found that advanced age and severity of infection were independent risk factors for vancomycin treatment failure. On the other hand, solid organ transplantation and a low vancomycin minimal inhibitory concentration were associated with successful vancomycin treatment. This study highlights the importance of vancomycin minimal inhibitory concentration in hVISA bacteremia.