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1.
Sci Rep ; 14(1): 21514, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39277704

RESUMO

Herein, we offer a model for estimating the tunneling conductivity of polymer-graphene nanocomposites based on interfacial properties, the proportion of networked graphene, and the wettability value between the polymer medium and the filler. The interfacial properties are influenced by the minimum diameter of the nanosheets (Dc), whose conductivity can be transferred to the medium via interfacial conduction (τ). These parameters impact the actual aspect ratio and the volume proportion of the filler, which, in turn, control the onset of percolation and the proportion of nanosheets in the network. We apply all these parameters to develop a novel model for estimating the conductivity of graphene systems. The predictions obtained from this model across different parameter ranges are discussed. Additionally, experimental measurements are employed to evaluate the proposed equations. High filler conductivity enhances the nanocomposite's conductivity by a strong interfacial conduction. However, the conductivity cannot be transferred to the polymer medium under condition of weak interfacial conduction. Furthermore, a robust interphase and a small Dc contribute to increased conductivity. Ultimately, the developed equations accurately predict the onset of percolation and conductivity, validated by real experimental data.

2.
J Gastrointest Surg ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39271001

RESUMO

BACKGROUND: Liver transplantation (LT) for nonresectable colorectal liver metastasis (NRCRLM) has become accepted for select patients meeting strict inclusion criteria. Advancements in patient selection and understanding of cancer biology may expand benefits to patients with colorectal liver metastasis (CRLM). In this meta-analysis, we sought to assess survival outcomes, recurrence patterns, and quality of life (QoL) after LT for CRLM. METHODS: PubMed, Embase, and Scopus databases were searched. A random-effect meta-analysis was conducted to obtain pooled overall survival (OS) and disease-free survival (DFS) rates and to compare QoL from baseline. Continuous data were analyzed, and standardized mean differences were reported. RESULTS: Overall, 16 studies (403 patients, 58.8% male sex) were included. The pooled 1-, 3-, and 5-year OS after LT for NRCRLM was 96% (95% CI: 92%-99%), 77% (95% CI: 62%-89%), and 53% (95% CI: 45%-61%), respectively. Moreover, the pooled 1-, 3-, and 5-year DFS was 58% (95% CI: 43%-72%), 33% (95% CI: 9%-61%), and 13% (95% CI: 4%-27%), respectively. Overall, 201 patients (49.8%) experienced recurrence during the follow-up period with the lungs being the most common site (45.8%). There was no significant differences in physical and emotional functioning, fatigue, and pain components of QoL at 6 months after LT compared with baseline (all P > .05). CONCLUSION: LT for NRCRLM demonstrated good OS outcomes with no differences in the QoL at 6 months after transplantation. Transplantation may represent a viable treatment option for NRCRLM.

3.
Nanotechnology ; 35(49)2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39284312

RESUMO

Reliable and cost-effective glucose sensors are in rising demand among diabetes patients. The combination of metals and conducting polymers creates a robust electrocatalyst for glucose oxidation, offering enzyme-free, high stability, and sensitivity with outstanding electrochemical results. Herein, graphene is grown on nickel foam by chemical vapor deposition to make a graphene@nickel foam scaffold (G@NF), on which silver nanoplates-polyaniline (Ag-PANI) 3D architecture is developed by sonication-assisted co-electrodeposition. The resulting binder-free 3D Ag-PANI/G@NF electrode was highly porous, as characterized by x-ray photoelectron spectroscopy, Field emission scanning electron microscope, x-ray diffractometer, FTIR, and Raman spectroscopy. The binder-free 3D Ag-PANI/G@NF electrode exhibits remarkable electrochemical efficiency with a superior electrochemical active surface area. The amperometric analysis provides excellent anti-interference performance, a low limit of deduction (0.1 nM), robust sensitivity (1.7 × 1013µA mM-1cm-2), and a good response time. Moreover, the Ag-PANI/G@NF enzyme-free sensor is utilized to observe glucose levels in human blood serums and exhibits excellent potential to become a reliable clinical glucose sensor.


Assuntos
Compostos de Anilina , Técnicas Eletroquímicas , Eletrodos , Grafite , Níquel , Prata , Grafite/química , Níquel/química , Prata/química , Humanos , Compostos de Anilina/química , Técnicas Eletroquímicas/métodos , Glicemia/análise , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Nanopartículas Metálicas/química , Glucose/análise , Limite de Detecção
4.
Surgery ; 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39299855

RESUMO

BACKGROUND: Patients diagnosed with upper gastrointestinal cancers often require extensive end-of-life care. We sought to investigate social determinants of health associated with disparities in the location of death among patients who died of upper gastrointestinal cancers. METHODS: Patients who died between 2003 and 2020 from esophageal cancer, gastric cancer, hepatobiliary cancer, and pancreatic cancer were identified using the Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research database. Social determinants of health were assessed using the Social Vulnerability Index. Patients were categorized on the basis of location of death: inpatient hospital, home, nursing home, hospice, and outpatient medical facility/emergency department. Multivariable regression and mediation analyses defined the association of patient race as well as social determinants of health with location of death. RESULTS: Among 815,780 decedents (esophageal cancer: 15.3%; gastric cancer: 3.6%; hepatobiliary cancer: 36.6%; pancreatic cancer: 54.5%), most were male (60.8%), aged 55-74 years (52.3%), and White (89.1%). Most decedents died at home (55.7%), followed by inpatient hospital (24.8%), hospice (9.0%), nursing home (8.1%), and outpatient medical facility/emergency department (2.5%). During the study period, location of death shifted notably from inpatient hospital (36.8% to 21.3%) to home (45.8% to 56.3%). Residents of high Social Vulnerability Index areas were more likely to die at inpatient hospital compared with home (31.8% vs 24.3%) (P < .001). Black race (reference: White; odds ratio; 0.41, 95% confidence interval, 0.40-0.42) and social vulnerability (reference: low Social Vulnerability Index; odds ratio, 0.64, 95% confidence interval, 0.63-0.65) remained independently associated with lower odds of dying at home compared with an inpatient hospital. Notably, 65% of the overall race-based association with death at inpatient hospital was driven indirectly through social determinants of health. CONCLUSION: Social determinants are important drivers of end-of-life care and impact the potential ability of patients with cancer to die at home.

5.
Curr Med Chem ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39234901

RESUMO

BACKGROUND: Geranyl acetate, a compound found in plant oils, has been studied for its potential effects on renal and cardiovascular ailments. OBJECTIVE: This study aimed to investigate the diuretic and anti-hyperuricemic properties of geranyl acetate in male Wistar rats using a hyperuricemia-induced rat model. METHODS: Molecular docking studies were conducted to assess geranyl acetate's interactions with various targets. in vitro studies were performed to evaluate its scavenging ability and inhibition of xanthine oxidase, urease, and acetylcholinesterase. Subsequently, we administered different doses of geranyl acetate (25, 50, and 100 mg/kg) and a reference drug (furosemide) to the rats to assess their acute and repeated dose diuretic effects over seven days. To understand the diuretic mechanism, we used inhibitors, such as L-- NAME, indomethacin, and atropine, prior to administering geranyl acetate. We also tested the anti-hyperuricemic potential of geranyl acetate on hyperuricemic rats. RESULTS: Molecular docking suggested strong binding between geranyl acetate and nitric oxide synthase. in vitro studies showed significant free radical scavenging activity and and inhibition of acetylcholinesterase, xanthine oxidase, and urease. The 100 mg/kg dose exhibited the most promising diuretic effects, with nitric oxide appearing to influence its action. Uric acid excretion increased at this dose, resembling allopurinol effects. CONCLUSION: Geranyl acetate has demonstrated significant diuretic and anti-hyperuricemic effects, likely influenced by nitric oxide release and inhibition of enzymes, like xanthine oxidase and urease. The findings have suggested potential benefits for individuals with kidney ailments, hypertension, and gout.

6.
Sci Rep ; 14(1): 20511, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227659

RESUMO

A two-step methodology has been developed utilizing the models of Paul and Takayanagi to determine the modulus of polymer halloysite nanotube (HNT) products. Initially, HNTs and the adjacent interphase are considered as pseudoparticles, and their modulus is evaluated using the Paul model. Subsequently, the modulus of a nanocomposite, consisting of a polymer medium and pseudoparticles, is predicted by Takayanagi equation. The impacts of various factors on the modulus of the products are analyzed, and the results from the two-step method are compared with experimental data from different samples. It has been observed that the modulus of samples progressively increases with an increase in interphase depth. Also, a higher interphase modulus contributes to an enhanced modulus of samples. Nevertheless, excessively high interphase moduli (Ei > 60 GPa) result in only a marginal improvement in the modulus of nanocomposites. Additionally, narrower HNTs are advantageous for producing stronger samples, though the modulus of the nanocomposites slightly diminishes at very high HNT radii (R > 55 nm). The outputs of two-step method agree with the experimental moduli of various HNT-filled systems.

7.
Ann Surg Oncol ; 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39277546

RESUMO

BACKGROUND: US News and World Report (USNWR) hospital rankings influence patient choice of hospital, but their association with surgical outcomes remains ill-defined. We sought to characterize clinical outcomes and costs of surgery for colon cancer among USNWR top ranked and unranked hospitals. METHODS: Using Medicare Standard Analytic Files, patients aged ≥65 years undergoing surgery for colon cancer were identified. Hospitals were categorized as 'ranked' or 'unranked' based on USNWR cancer hospital rankings. One-to-one matching was performed between patients treated at ranked and unranked hospitals, and clinical outcomes and costs of surgery were compared. RESULTS: Among 50 ranked and 2522 unranked hospitals, 13,650 patient pairs were compared. Overall, 30-day mortality was 2.13% in ranked hospitals versus 3.68% in unranked hospitals (p < 0.0001), and the overall paired cost difference was $8159 (p < 0.0001). As patient risk increased, 30-day mortality differences became larger, with the ranked hospitals having 30-day mortality of 7.59% versus 11.84% for unranked hospitals among the highest-risk patients (p < 0.0001). Overall paired cost differences also increased with increasing patient risk, with cost of care being $72,229 for ranked hospitals versus $56,512 for unranked hospitals among the highest-risk patients (difference = $14,394; p = 0.02). The difference in cost per 1% reduction in 30-day mortality was $9009 (95% confidence interval [CI] $6422-$11,597) for lowest-risk patients, which dropped to $3387 (95% CI $2656-$4119) for highest-risk patients (p < 0.0001). CONCLUSION: Treatment at USNWR-ranked hospitals, particularly for higher-risk patients, was associated with better outcomes but higher-cost care. The benefit of being treated at highly ranked USNWR hospitals was most pronounced among high-risk patients.

8.
HPB (Oxford) ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39098450

RESUMO

BACKGROUND: We sought to assess the impact of various perioperative factors on the risk of severe complications and post-surgical mortality using a novel maching learning technique. METHODS: Data on patients undergoing resection for HCC were obtained from an international, multi-institutional database between 2000 and 2020. Gradient boosted trees were utilized to construct predictive models. RESULTS: Among 962 patients who underwent HCC resection, the incidence of severe postoperative complications was 12.7% (n = 122); in-hospital mortality was 2.9% (n = 28). Models that exclusively used preoperative data achieved AUC values of 0.89 (95%CI 0.85 to 0.92) and 0.90 (95%CI 0.84 to 0.96) to predict severe complications and mortality, respectively. Models that combined preoperative and postoperative data achieved AUC values of 0.93 (95%CI 0.91 to 0.96) and 0.92 (95%CI 0.86 to 0.97) for severe morbidity and mortality, respectively. The SHAP algorithm demonstrated that the factor most strongly predictive of severe morbidity and mortality was postoperative day 1 and 3 albumin-bilirubin (ALBI) scores. CONCLUSION: Incorporation of perioperative data including ALBI scores using ML techniques can help risk-stratify patients undergoing resection of HCC.

9.
World J Surg ; 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39148145

RESUMO

BACKGROUND: Access to healthcare providers is a key factor in reducing cancer incidence and mortality, underscoring the significance of provider density as a crucial metric of health quality. We sought to characterize the association of provider density on hepatobiliary cancer population-level incidence and mortality. STUDY DESIGN: County-level hepatobiliary cancer incidence and mortality data from 2016 to 2020 and provider data from 2016 to 2018 were obtained from the CDC and Area Health Resource File. Multivariable logistic regression was utilized to evaluate the relationship between provider density and hepatobiliary cancer incidence and mortality. RESULTS: Among 1359 counties, 851 (62.6%) and 508 (37.4%) counties were categorized as urban and rural, respectively. The median number of providers in any given county was 104 (IQR: 44-306), while provider density was 120.1 (IQR: 86.7-172.2) per 100,000 population; median household income was $51,928 (IQR: $45,050-$61,655). Low provider-density counties were more likely to have a greater proportion of residents over 65 years of age (52.7% vs. 49.6%) who were uninsured (17.4% vs. 13.2%) versus higher provider-density counties (p < 0.05). Moreover, all-stage incidence, late-stage incidence, and mortality rates were higher in counties with low provider density. On multivariable analysis, moderate, and high provider density were associated with lower odds of all-stage incidence, late-stage incidence, and mortality. CONCLUSION: Higher county-level provider density was associated with lower hepatobiliary cancer-related incidence and mortality. Efforts to increase access to healthcare providers may improve healthcare equity as well as long-term cancer outcomes.

10.
Ann Surg Oncol ; 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39158639

RESUMO

BACKGROUND: Primary care (PC) is essential to overall wellness and management of comorbidities. In turn, patients without adequate access to PC may face healthcare disparities. We sought to characterize the impact of established PC on postoperative outcomes among patients undergoing a surgical procedure for a digestive tract cancer. METHODS: Medicare beneficiaries with a diagnosis of hepatobiliary, pancreas, and colorectal cancer between 2005 and 2019 were identified within the Surveillance, Epidemiology, and End Results program and Medicare-linked database. Individuals who did versus did not have PC encounters within 1-year before surgery were identified. A postoperative textbook outcome (TO) was defined as the absence of complications, no prolonged hospital stay, no readmission within 90 days, and no mortality. RESULTS: Among 63,177 patients, 50,974 (80.7%) had at least one established PC visit before surgery. Patients with established PC were more likely to achieve TO (odds ratio [OR], 1.14; 95% confidence interval [CI], 1.09-1.19) with lower odds for complications (OR, 0.85; 95% CI, 0.72-0.89), extended hospital stay (OR, 0.86; 95% CI, 0.81-0.94), 90-day readmission (OR, 0.94; 95% CI, 0.90-0.99), and 90-day mortality (OR, 0.87; 95% CI, 0.79-0.96). In addition, patients with established PC had a 4.1% decrease in index costs and a 5.2% decrease in 1-year costs. Notably, patients who had one to five visits with their PC in the year before surgery had improved odds of TO (OR, 1.21; 95% CI, 1.16-1.27), whereas individuals with more than 10 visits had lower odds of a postoperative TO (OR, 0.91; 95% CI, 0.84-0.98). CONCLUSION: Most Medicare beneficiaries with digestive tract cancer had established PC within the year before their surgery. Established PC was associated with a higher probability of achieving ideal outcomes and lower costs. In contrast, patients with more than 10 PC appointments, which was likely a surrogate of overall comorbidity burden, experienced no improvement in postoperative outcomes.

11.
Ann Surg ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39176887

RESUMO

OBJECTIVE: We sought to define the association of privilege on rates of unplanned surgery and perioperative outcomes for access-sensitive surgical conditions. BACKGROUND: Social determinants of health (SDOH) are critical in influencing timely access to healthcare. Privilege represents a right, benefit, advantage, or opportunity that positively influences all SDOH. METHODS: The California Department of Health Care Access and Information (HCAI) database identified patients who underwent abdominal aortic aneurysm repair, ventral hernia repair, or colectomy for colon cancer between 2017 and 2020 and was merged using ZIP codes with the Index of Concentration of Extremes, a validated measure of racial and economic privilege obtained from the American Community Survey. Clustered multivariable regression was performed to assess the association between privilege and outcomes. RESULTS: Among 185,316 patients who underwent a surgical procedure for one of three access-sensitive surgical conditions, roughly 1 in 5 individuals resided in areas with the highest (Q5; n=37,308; 20.1%) or lowest (Q1; n=36,352, 19.6%) privilege. Nearly one-half of the surgeries were unplanned (n=88,814, 46.9%), and colectomy for colon cancer was the most performed emergent procedure. Patients residing in the lowest privileged areas had higher rates of unplanned surgery compared with those residing in the highest privilege (Q1; 55.4% vs. 39.4%; referent: Q5; adjusted odds ratio [OR], 1.23, 95%CI 1.16-1.31; P<0.001). For each access-sensitive surgical condition, patients in the least privileged areas were more likely to experience higher rates of inpatient mortality (Q1; 3.1% vs. 2.1%; referent: Q5; adjusted OR, 1.41, 95%CI 1.24-1.60; P<0.001), perioperative complications (Q1; 30.4% vs. Q5; 23.8%; referent: Q5; adjusted OR, 1.24, 95%CI 1.18-1.31; P<0.001) and extended hospital stays (Q1; 26.3% vs. 20.1%; referent: Q5; adjusted OR, 1.16, 95%CI 1.09-1.22; P<0.001). CONCLUSIONS AND RELEVANCE: Privilege was associated with rates of unplanned surgery and adverse clinical outcomes. This indicates the role privilege as a key SDOH that influences patient access to and quality of surgical care.

12.
J Surg Res ; 301: 664-673, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39146835

RESUMO

INTRODUCTION: Environmental hazards may influence health outcomes and be a driver of health inequalities. We sought to characterize the extent to which social-environmental inequalities were associated with surgical outcomes following a complex operation. METHODS: In this cross-sectional study, patients who underwent abdominal aortic aneurysm repair, coronary artery bypass grafting, colectomy, pneumonectomy, or pancreatectomy between 2016 and 2021 were identified from Medicare claims data. Patient data were linked with social-environmental data sourced from Centers for Disease Control and Agency for Toxic Substances and Disease Registry data based on county of residence. The Environmental Justice Index social-environmental ranking (SER) was used as a measure of environmental injustice. Multivariable regression analysis was performed to assess the relationship between SER and surgical outcomes. RESULTS: Among 1,052,040 Medicare beneficiaries, 346,410 (32.9%) individuals lived in counties with low SER, while 357,564 (33.9%) lived in counties with high SER. Patients experiencing greater social-environmental injustice were less likely to achieve textbook outcome (odds ratio 0.95, 95% confidence interval 0.94-0.96, P < 0.001) and to be discharged to an intermediate care facility or home with a health agency (odds ratio 0.97, 95% confidence interval 0.96-0.98, P < 0.001). CONCLUSIONS: Cumulative social and environmental inequalities, as captured by the Environmental Justice Index SER, were associated with postoperative outcomes among Medicare beneficiaries undergoing a range of surgical procedures. Policy makers should focus on environmental, as well as socioeconomic injustice to address preventable health disparities.

13.
J Gastrointest Surg ; 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39197678

RESUMO

PURPOSE: We sought to develop an artificial intelligence (AI)-based model to predict early recurrence (ER) after curative-intent resection of neuroendocrine liver metastases (NELMs). METHODS: Patients with NELM who underwent resection were identified from a multi-institutional database. ER was defined as recurrence within 12 months of surgery. Different AI-based models were developed to predict ER using 10 clinicopathologic factors. RESULTS: Overall, 473 patients with NELM were included. Among 284 patients with recurrence (60.0%), 118 patients (41.5%) developed an ER. An ensemble AI model demonstrated the highest area under receiver operating characteristic curves of 0.763 and 0.716 in the training and testing cohorts, respectively. Maximum diameter of the primary neuroendocrine tumor, NELM radiologic tumor burden score, and bilateral liver involvement were the factors most strongly associated with risk of NELM ER. Patients predicted to develop ER had worse 5-year recurrence-free survival and overall survival (21.4% vs 37.1% [P = .002] and 61.6% vs 90.3% [P = .03], respectively) than patients not predicted to recur. An easy-to-use tool was made available online: (https://altaf-pawlik-nelm-earlyrecurrence-calculator.streamlit.app/). CONCLUSION: An AI-based model demonstrated excellent discrimination to predict ER of NELM after resection. The model may help identify patients who can benefit the most from curative-intent resection, risk stratify patients according to prognosis, as well as guide tailored surveillance and treatment decisions including consideration of nonsurgical treatment options.

14.
ACS Omega ; 9(31): 33397-33407, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39130539

RESUMO

To delineate a powerful reservoir model, rock type identification is an essential task. Recognizing intervals with promising reservoir quality in a heterogeneous reservoir, such as the Pab Formation, using well logs is critical for better exploration, because coring programs are always impractical due to time and cost constraints. Rock types are described by specific log responses, which are ultimately distinguished with the help of electrofacies. The current study uses a cluster analysis technique for the evaluation of reservoir rock types in the identified sand units. K-means cluster analysis is employed to define electrofacies, which are ultimately classified into four rock types on the basis of reservoir quality, from bad to excellent. Rock typing using cluster analysis has been done for four wells, and a correlation has been made to depict changes in electrofacies. From well-to-well correlation, it can be inferred that the reservoir quality of the Pab Formation at the lower portion of Zamzama-02 and 05 wells is excellent and is defined by rock type 4. The Zamzama-03 well in the southwestern region, on the other hand, has good to moderate reservoir quality, as demonstrated by dominating rock types 3 and 2, respectively. The applied prediction technique to the studied field provides continuous rock type identification for the entire reservoir. Using this methodology in defining rock type is cost-effective, requires less time in the demarcation of zones of interest, and is more accurate than manual analysis of the heterogeneous and thick Pab Formation. The studied approach is not only useful in the exploitation of the heterogeneous Pab Formation but also can be applied to other heterogeneous sandstone reservoirs elsewhere.

15.
Transplantation ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995240

RESUMO

BACKGROUND: We sought to define the survival benefit of kidney transplantation versus long-term dialysis relative to waitlist time on dialysis, social vulnerability, and age among end-stage renal transplant candidates. METHODS: End-stage renal disease patients who were candidates for their first deceased donor kidney transplantation between 2008 and 2020 were identified using the US Renal Data System. Survival probabilities for patient survival were compared using the restricted mean survival times (RMSTs) across different age and social vulnerability index (SVI) ranges. RESULTS: Among 149 923 patients, 68 795 (45.9%) patients underwent a kidney transplant and 81 128 (54.1%) remained on dialysis. After propensity-score matching (n = 58 035 in each cohort), the 5-y RMST difference between kidney transplant and dialysis demonstrated an increasing trend in mean life-years gained within 5 y of follow-up relative to advancing age (<30 y: 0.40 y, 95% confidence interval, 0.36-0.44 y versus >70 y: 0.75 y, 95% confidence interval, 0.70-0.80 y). Conversely, disparities in 5-y RMSTs remained consistent relative to social vulnerability (median 5-y RMST difference: 0.62 y comparing low versus high SVI). When considering waitlist duration, stratified analyses demonstrated increasing trends across different age groups with the largest RMST differences observed among older patients aged ≥70 y. Notably, longer waitlist durations (>3 y) yielded more pronounced RMST differences compared with shorter durations (<1 y). CONCLUSIONS: These data underscore the survival benefit associated with kidney transplantation over long-term dialysis across various age and SVI ranges. Transplantation demonstrated a greater advantage among older patients who had a longer waitlist duration.

16.
Materials (Basel) ; 17(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38998183

RESUMO

Confined masonry (CM) construction is being increasingly adopted for its cost-effectiveness and simplicity, particularly in seismic zones. Despite its known benefits, limited research exists on how the stiffness of confining elements influences the in-plane behavior of CM. This study conducted a comprehensive parametric analysis using experimentally validated numerical models of single-wythe, squat CM wall panels under quasi-static reverse cyclic loading. Various cross-sections and reinforcement ratios were examined to assess the impact of the confining element stiffness on the deformation response, the cracking mechanism, and the hysteretic behavior. The key findings included the observation of symmetrical hysteresis in experimental CM panels under cyclic loading, with a peak lateral strength of 114.3 kN and 108.5 kN in push-and-pull load cycles against 1.7% and 1.3% drift indexes, respectively. A finite element (FE) model was developed based on a simplified micro-modeling approach, demonstrating a maximum discrepancy of 2.6% in the peak lateral load strength and 5.4% in the initial stiffness compared to the experimental results. The parametric study revealed significant improvements in the initial stiffness and seismic strength with increased depth and reinforcement in the confining elements. For instance, a 35% increase in the lateral strength was observed when the depth of the confining columns was augmented from 150 mm to 300 mm. Similarly, increasing the steel reinforcement percentage from 0.17% to 0.78% resulted in a 16.5% enhancement in the seismic strength. These findings highlight the critical role of the stiffness of confining elements in enhancing the seismic performance of CM walls. This study provides valuable design insights for optimizing CM construction in seismic-prone areas, particularly regarding the effects of confining element dimensions and reinforcement ratios on the structural resilience.

17.
Chemosphere ; 363: 142823, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38996978

RESUMO

Struvite biomineralization is an ecologically sound technology, adept at the efficient recovery and recycling of phosphorus from wastewater. However, the biomineralization process is often perturbed by the presence of antibiotics, notably tetracycline (TC), the impact of which on the biomineralization system has not been elucidated. This study examines the efficacy of Bacillus cereus LB-9 in struvite biomineralization, focusing on the precipitates' composition, morphology, and TC content. LB-9 facilitate an alkaline environment that effectively recovering nitrogen and phosphorus. These findings indicate that TC retards the initial formation of struvite and the concurrent recovery of nitrogen and phosphorus. However, at concentrations below 10 mg/L TC concentrations, TC enhanced struvite production (0.38g) by stimulating LB-9's growth and metabolic activity. Conversely, at a concentration of 10 mg/L TC, the strain's activity was markedly suppressed within the initial four days. This data suggests that TC promotes the strain's proliferation and metabolism, potentially through cellular secretions, thereby augmenting phosphorus recovery from wastewater. Notably, the recovered struvite doesn't contain TC, aligning with regulatory standards for agricultural application. In summary, LB-9-mediated struvite recovery is an effective strategy for producing phosphorus-enriched fertilizers and mitigating TC contamination, offering significant implications for wastewater treatment and industrial process development, particularly in the context of prevalent TC in wastewater.


Assuntos
Bacillus cereus , Fósforo , Estruvita , Tetraciclina , Águas Residuárias , Fósforo/metabolismo , Águas Residuárias/química , Bacillus cereus/metabolismo , Estruvita/química , Biomineralização , Antibacterianos , Poluentes Químicos da Água/metabolismo , Eliminação de Resíduos Líquidos/métodos , Nitrogênio/metabolismo , Fertilizantes
18.
Artigo em Inglês | MEDLINE | ID: mdl-39060655

RESUMO

To evaluate left atrial (LA) function and strain parameters by cardiac magnetic resonance imaging (CMR) in patients with non-ischemic cardiomyopathy (NICM) and evaluate the association of these parameters with long-term clinical outcomes. We retrospectively included 92 patients with NICM and 50 subjects with no significant cardiovascular disease (control group). We calculated LA volumes using the Simpson area-length method to derive LA ejection fraction and expansion index. LA reservoir (ƐR), conduit (ƐCD), and contractile strain (ƐCT) were measured using dedicated CMR software (cvi42, Circle Cardiovascular Imaging Inc., version 5.14). An adjusted multivariate regression analysis was performed to determine the association of LA parameters with death and heart failure hospitalization (HFH). NICM patients were older with male preponderance. The mean age for NICM patients was 59.6 ± 15.9 years, 64% males, and 73% whites versus 52.2 ± 12.4 years, 34% male and 64% white for controls. LA strain patterns were significantly lower in NICM patients when compared to controls. During a median follow-up of 58.9 months, 12 patients (13%) died and 33(35.9%) had a HFH. None of the clinical or CMR factors were significantly associated with death. On multivariate analysis, after adjusting for age and significant univariate variables, ƐR was the only variable significantly associated with the HFH (OR 0.98, CI 0.96-1.0). Unadjusted and adjusted Cox proportional hazard models divided by the median ƐR (~ 18%) showed a significant difference in HFH over time (χ2 statistic = 21.1; P value = 0.03). In NICM patients, all LA strain components were reduced. ƐR was found to be significantly associated with HFH.

19.
Eur J Surg Oncol ; 50(9): 108532, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39004061

RESUMO

INTRODUCTION: Accurate prediction of patients at risk for early recurrence (ER) among patients with colorectal liver metastases (CRLM) following preoperative chemotherapy and hepatectomy remains limited. METHODS: Patients with CRLM who received chemotherapy prior to undergoing curative-intent resection between 2000 and 2020 were identified from an international multi-institutional database. Multivariable Cox regression analysis was used to assess clinicopathological factors associated with ER, and an online calculator was developed and validated. RESULTS: Among 768 patients undergoing preoperative chemotherapy and curative-intent resection, 128 (16.7 %) patients had ER. Multivariable Cox analysis demonstrated that Eastern Cooperative Oncology Group Performance status ≥1 (HR 2.09, 95%CI 1.46-2.98), rectal cancer (HR 1.95, 95%CI 1.35-2.83), lymph node metastases (HR 2.39, 95%CI 1.60-3.56), mutated Kirsten rat sarcoma oncogene status (HR 1.95, 95%CI 1.25-3.02), increase in tumor burden score during chemotherapy (HR 1.51, 95%CI 1.03-2.24), and bilateral metastases (HR 1.94, 95%CI 1.35-2.79) were independent predictors of ER in the preoperative setting. In the postoperative model, in addition to the aforementioned factors, tumor regression grade was associated with higher hazards of ER (HR 1.91, 95%CI 1.32-2.75), while receipt of adjuvant chemotherapy was associated with lower likelihood of ER (HR 0.44, 95%CI 0.30-0.63). The discriminative accuracy of the preoperative (training: c-index: 0.77, 95%CI 0.72-0.81; internal validation: c-index: 0.79, 95%CI 0.75-0.82) and postoperative (training: c-index: 0.79, 95%CI 0.75-0.83; internal validation: c-index: 0.81, 95%CI 0.77-0.84) models was favorable (https://junkawashima.shinyapps.io/CRLMfollwingchemotherapy/). CONCLUSIONS: Patient-, tumor- and treatment-related characteristics in the preoperative and postoperative setting were utilized to develop an online, easy-to-use risk calculator for ER following resection of CRLM.


Assuntos
Neoplasias Colorretais , Hepatectomia , Neoplasias Hepáticas , Recidiva Local de Neoplasia , Humanos , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Masculino , Feminino , Neoplasias Colorretais/patologia , Pessoa de Meia-Idade , Idoso , Carga Tumoral , Metástase Linfática , Estudos Retrospectivos , Quimioterapia Adjuvante , Medição de Risco , Modelos de Riscos Proporcionais
20.
JAMA Surg ; 159(9): 1060-1070, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39046733

RESUMO

Importance: Gender inequities and limited representation are an obstacle to surgical workforce diversification. There has been limited examination of gender-based disparities in billing practices among surgeons. Objective: To evaluate variations in practice metrics and billing practices among female and male surgeons and identify factors associated with gender disparities in Medicare reimbursements. Design, Setting, and Participants: This retrospective cross-sectional study used publicly available Medicare Fee-for-Service Provider Utilization and Payment data from January to December 31, 2021, to identify demographics, annual services provided, and financial payments and charges for general surgeons, surgical oncologists, and colorectal surgeons. Data were analyzed from November 2023 to February 2024. Exposure: The primary exposure of interest was surgeon gender (ie, female or male). Main Outcomes and Measures: The annual total submitted charges and payments submitted in 2021 by female and male surgeons were assessed. Additionally, the total number and types of services provided each year and the number of beneficiaries treated were examined. Multivariable linear regression models were used to evaluate the association of surgeon gender with payments, number of services, and beneficiaries. Results: A total of 20 549 general surgeons (5036 [24.5%] female; 15 513 [75.5%] male), 1065 surgical oncologists (450 [42.3%] female; 615 [57.7%] male), and 1601 colorectal surgeons (432 [27.0%] female; 1169 [73.0%] male) were included. Across all surgical subspecialties, female surgeons billed fewer mean (SE) Medicare charges (general surgeons: 30.1% difference; $224 934.80 [$3846.97] vs $321 868.50 [$3933.57]; surgical oncologists: 27.5% difference; $277 901.70 [$22 857.37] vs $382 882.90 [$19 566.06]; colorectal surgeons: 21.7% difference; $274 091.70 [$10 468.48] vs $350 146.10 [$8741.66]; all P < .001) and received significantly lower mean (SE) reimbursements (general surgeons: 29.0% difference; $51 787.61 [$917.91] vs $72 903.12 [$890.35]; surgical oncologists: 23.6% difference; $57 945.18 [$3853.28] vs $75 778.22 [$2622.75]; colorectal surgeons: 24.5% difference; $63 117.01 [$2248.10] vs $83 598.53 [$1934.77]; all P < .001). On multivariable analysis, a reimbursement gap remained across all 3 surgical subspecialties (general surgeons: -$14 963.46 [95% CI, -$18 822.27 to -$11 104.64] [P < .001]; surgical oncologists: -$8354.69 [95% CI, -$15 018.12 to -$1691.25] [P = .01]; colorectal surgeons: -$4346.73 [95% CI, -$7660.15 to -$1033.32] [P = .01]). Conclusions and Relevance: In this cross-sectional study, there was considerable gender-based variation in practice patterns and reimbursement among different surgical subspecialties serving the Medicare population. Differences in mean payment per service were associated with variations in billing and coding strategies among female and male surgeons.


Assuntos
Medicare , Especialidades Cirúrgicas , Humanos , Estados Unidos , Feminino , Medicare/economia , Masculino , Estudos Transversais , Estudos Retrospectivos , Especialidades Cirúrgicas/economia , Cirurgiões/economia , Cirurgiões/estatística & dados numéricos , Planos de Pagamento por Serviço Prestado/economia , Fatores Sexuais
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