scholarly journals Analyzing Mechanisms in Co(I) Redox Catalysis Using a Pattern Recognition Platform

2020 ◽  
Author(s):  
Tianhua Tang ◽  
Christopher Sandford ◽  
Shelley D. Minteer ◽  
Matthew Sigman
Keyword(s):  
Pattern Recognition ◽  
Bond Cleavage ◽  
Linear Regression Analysis ◽  
Benzyl Bromide ◽  
Kinetic Studies ◽  
Outer Sphere ◽  
Redox Catalysis ◽  
Tridentate Ligands ◽  
Electron Transfer Mechanism ◽  
Multivariable Linear Regression Analysis

Redox catalysis has been broadly utilized in electrochemical synthesis due to its kinetic advantages over direct electrolysis. The appropriate choice of redox mediator can avoid electrode passivation and overpotential, which strongly inhibit the efficient activation of substrates in electrolysis. Despite the benefits brought by redox catalysis, establishing the precise nature of substrate activation remains challenging. Herein, we determine that a Co(I) complex bearing two <i>N</i>,<i>N</i>,<i>N</i>-tridentate ligands acts as a competent redox catalyst for the reduction of benzyl bromide substrates. Kinetic studies combining electroanalytical techniques with multivariable linear-regression analysis were conducted, disclosing an outer-sphere electron-transfer mechanism, which occurs in concert with C–Br bond cleavage. Furthermore, we apply a pattern recognition platform to distinguish between mechanisms in the activation of benzyl bromides, found to be dependent on the ligation state of the cobalt(I) center and ligand used.

scholarly journals Analyzing Mechanisms in Co(I) Redox Catalysis Using a Pattern Recognition Platform

2020 ◽  
Author(s):  
Tianhua Tang ◽  
Christopher Sandford ◽  
Shelley D. Minteer ◽  
Matthew Sigman
Keyword(s):  
Pattern Recognition ◽  
Bond Cleavage ◽  
Linear Regression Analysis ◽  
Benzyl Bromide ◽  
Kinetic Studies ◽  
Outer Sphere ◽  
Redox Catalysis ◽  
Tridentate Ligands ◽  
Electron Transfer Mechanism ◽  
Multivariable Linear Regression Analysis

Redox catalysis has been broadly utilized in electrochemical synthesis due to its kinetic advantages over direct electrolysis. The appropriate choice of redox mediator can avoid electrode passivation and overpotential, which strongly inhibit the efficient activation of substrates in electrolysis. Despite the benefits brought by redox catalysis, establishing the precise nature of substrate activation remains challenging. Herein, we determine that a Co(I) complex bearing two <i>N</i>,<i>N</i>,<i>N</i>-tridentate ligands acts as a competent redox catalyst for the reduction of benzyl bromide substrates. Kinetic studies combining electroanalytical techniques with multivariable linear-regression analysis were conducted, disclosing an outer-sphere electron-transfer mechanism, which occurs in concert with C–Br bond cleavage. Furthermore, we apply a pattern recognition platform to distinguish between mechanisms in the activation of benzyl bromides, found to be dependent on the ligation state of the cobalt(I) center and ligand used.

scholarly journals Analyzing mechanisms in Co(i) redox catalysis using a pattern recognition platform

2021 ◽  
Vol 12 (13) ◽  
pp. 4771-4778
Author(s):  
Tianhua Tang ◽  
Christopher Sandford ◽  
Shelley D. Minteer ◽  
Matthew S. Sigman
Keyword(s):  
Pattern Recognition ◽  
Electron Transfer ◽  
Linear Regression ◽  
Electrochemical Reduction ◽  
Kinetic Studies ◽  
Outer Sphere ◽  
Cobalt Complexes ◽  
Transfer Mechanism ◽  
Redox Catalysis ◽  
Electron Transfer Mechanism

Through kinetic studies combining electroanalytical techniques with multivariable linear-regression (MLR) analysis, a pattern recognition platform is established to determine the electron-transfer mechanism (inner-sphere or outer-sphere) of an electrochemical reduction of benzyl bromides, mediated by different cobalt complexes.

scholarly journals Costs of Hospitalisation Due to Stroke: Linked Registry and Administrative Clinical Costing Study

2020 ◽  
Vol 5 (5) ◽  
Author(s):  
Joosup Kim
Keyword(s):  
Length Of Stay ◽  
Disease Burden ◽  
Linear Regression Analysis ◽  
Quality Data ◽  
Clinical Registry ◽  
Costing Study ◽  
Multivariable Linear Regression Analysis ◽  
Hospital Administrative ◽  
Mean Cost ◽  
Administrative Datasets

IntroductionRoutine clinical costing of hospital care provided for a representative sample of patients informs a national price for hospital reimbursement according to the diagnosis related group of a patient. These clinical costing data are available for linkage as part of hospital administrative datasets. Objectives and ApproachThe Australian Stroke Clinical Registry (AuSCR) is a national data collection program used to monitor the quality of care provided to patients who have been hospitalised with a clinical diagnosis of stroke or transient ischaemic attack (TIA). For the Stroke123 project, registrants from the Australian Stroke Clinical Registry in 2009-2013 were linked to hospital administrative datasets in four states (Victoria, Queensland, New South Wales and Western Australia). Clinical costing data were obtained for the cohort in Queensland only. Using these clinical costing data, we aimed to determine the costs of hospitalisations according to clinical and demographic characteristics of patients. Reliability of clinical costing data were tested by assessing the association with disease burden and length of stay using multivariable linear regression analysis. ResultsOf the 5522 patient episodes (from 23 hospitals), clinical costing data were available for 3909 (71%, from 22 hospitals). Patients with clinical costing data were more often aged <65 years (30% vs 24%, p<0.001) and more often male (56% vs 49%, p<0.001) than those without these data. Mean cost of an episode was $12,129. Episodes of intracerebral haemorrhage had a mean cost of $18,315, which was greater than the mean costs of ischaemic stroke ($13,925), TIA ($5,247) and undetermined stroke ($8,996). Greater costs were associated with greater disease burden according to the Charlson Comorbidity Index (p<0.001) and length of stay (p<0.001). Conclusion / ImplicationsIntegration of clinical quality data and costs will enable more holistic assessment and monitoring of the effects of quality improvement initiatives and therapeutic advances.

scholarly journals Factors Affecting Birthweight Decline in Recent Japan Based on Birth Certificates

2020 ◽  
Author(s):  
Noriko Kato ◽  
Catherine Sauvaget ◽  
Honami Yoshida ◽  
Tetsuji Yokoyama ◽  
Nobuo Yoshiike
Keyword(s):  
Birth Order ◽  
Gestational Age ◽  
Maternal Diet ◽  
Linear Regression Analysis ◽  
Vital Statistics ◽  
Birth Certificates ◽  
Factors Affecting ◽  
New Information ◽  
Multivariable Linear Regression Analysis ◽  
Birth Records

Abstract Background:Birthweight is declining consistently for more than 30 years in Japan. Rapid rise in low birth weight infant counts one of the worst among OECD countries.Objective: To add new information for clarifying the factors associated with the decline in birthweight in Japan.Methods: Government vital statistics records were used under permission. 40,968,266 birth records born between 1980 and 2004 were analyzed. Multivariable linear regression analysis was used to examine whether the decline in the birthweight could be explained by obstetrical variables such as gestational age and plurality.Results: From 1980 to 2004, we observed a decline in mean birthweight with yearly effect of -8.07g, which got steeper after 1985 and persisted until 1999, and plateaued thereafter. After adjustment for gestational age, neonatal gender, birth order, plurality, father age, yearly effect became -5.13g, between 1980 and 2004. Conclusion：Recent decreases in birthweight among Japanese neonates were not fully explained by trends of gestational age, sex, birth order, plurality and father age. We should consider additional factors such as pre-pregnant maternal BMI and maternal diet.

The Association of Atherosclerotic Cardiovascular Disease and Statin Use With Inflammation and Treatment Outcomes in Tuberculosis

2021 ◽  
Author(s):  
Vignesh Chidambaram ◽  
Jennie Ruelas Castillo ◽  
Amudha Kumar ◽  
Justin Wei ◽  
Siqing Wang ◽  
...  
Keyword(s):  
Cardiovascular Disease ◽  
Linear Regression Analysis ◽  
Elevated Serum ◽  
University Hospital ◽  
Sputum Smear ◽  
Atherosclerotic Cardiovascular Disease ◽  
All Cause Mortality ◽  
Multivariable Linear Regression Analysis ◽  
Related Mortality ◽  
Statin Use

Abstract Objective: Tuberculosis (TB) and atherosclerotic cardiovascular disease (ASCVD) have a close epidemiological and pathogenetic overlap. Thus, it becomes essential to understand the relationship between ASCVD and TB outcomes.Methods:From our retrospective cohort on drug-susceptible TB patients at the National Taiwan University Hospital, we assessed the association of pre-existing ASCVD (coronary artery disease (CAD) and atherothrombotic stroke (ATS)) with 9-month all-cause and infection-related mortality and the extent of mediation by systemic inflammatory markers. We determined the effect of pre-existing ASCVD on 2-month sputum microbiological status. Among ASCVD patients, we assessed the association of statin use on mortality.Results:Nine-month all-cause mortality was higher in CAD patients with prior acute myocardial infarction (CAD+AMI+) (adjusted HR 2.01, 95%CI 1.38-3.00) and ATS patients (aHR 2.79, 95%CI 1.92-4.07) and similarly, for infection-related mortality was higher in CAD+AMI+ (aHR 1.95, 95%CI 1.17-3.24) and ATS (aHR 2.04, 95%CI 1.19-3.46) after adjusting for confounding factors. Pre-existing CAD (AMI- or AMI+) or ATS did not change sputum culture conversion or sputum smear AFB positivity at 2 months. The CAD+AMI+ group had significantly higher levels of CRP at TB diagnosis in the multivariable linear regression analysis (Adjusted B(SE) 1.24(0.62)). CRP mediated 66% (p=0.048) and 25% (p=0.033) of the association all-cause mortality with CAD+AMI- and CAD+AMI+, respectively. ConclusionsIn summary, patients with ASCVD have higher hazards of 9-month all-cause and infection-related mortality, with elevated serum inflammation mediating one to three-quarters of this association when adjusted for confounders. Statin use was associated with lower all-cause mortality among patients with ASCVD.

scholarly journals Effect of Number of Clinics and Panel Size on Patient Continuity for Medical Residents

2009 ◽  
Vol 1 (2) ◽  
pp. 310-315 ◽  
Author(s):  
Maureen D. Francis ◽  
Whitney E. Zahnd ◽  
Andrew Varney ◽  
Steven L. Scaife ◽  
Mark L. Francis
Keyword(s):  
Regression Analysis ◽  
Linear Regression ◽  
Linear Regression Analysis ◽  
Medical Residents ◽  
Panel Size ◽  
Medical Education Program ◽  
Internal Medicine Residency Training ◽  
Multivariable Linear Regression Analysis ◽  
Linear Regression Modeling ◽  
Attending Physician

Abstract Background Accreditation Council for Graduate Medical Education program requirements for internal medicine residency training include a longitudinal, continuity experience with a panel of patients. Objective To determine whether the number of resident clinics, the resident panel size, and the supervising attending physician affect patient continuity. To determine the number of clinics and the panel size necessary to maximize patient continuity. Design We used linear regression modeling to assess the effect of number of attended clinics, the panel size, and the attending physician on patient continuity. Participants Forty medicine residents in an academic medicine clinic. Measurements Percent patient continuity by the usual provider of care method. Results Unadjusted linear regression analysis showed that patient continuity increased 2.3% ± 0.7% for each additional clinic per 9 weeks or 0.4% ± 0.1% for each additional clinic per year (P  =  .003). Conversely, patient continuity decreased 0.7% ± 0.4% for every additional 10 patients in the panel (P  =  .04). When simultaneously controlling for number of clinics, panel size, and attending physician, multivariable linear regression analysis showed that patient continuity increased 3.3% ± 0.5% for each additional clinic per 9 weeks or 0.6% ± 0.1% for each additional clinic per year (P &lt; .001). Conversely, patient continuity decreased 2.2% ± 0.4% for every additional 10 patients in the panel (P &lt; .001). Thus, residents who actually attend at least 1 clinic per week with a panel size less than 106 patients can achieve 50% patient continuity. Interestingly, the attending physician accounted for most of the variability in patient continuity (51%). Conclusions Patient continuity for residents significantly increased with increasing numbers of clinics and decreasing panel size and was significantly influenced by the attending physician.

scholarly journals Intracellular and Plasma Trough Concentration and Pharmacogenetics of Telaprevir

2015 ◽  
Vol 18 (2) ◽  
pp. 171 ◽  
Author(s):  
Jessica Cusato ◽  
Sarah Allegra ◽  
Amedeo De Nicolò ◽  
Lucio Boglione ◽  
Giovanna Fatiguso ◽  
...  
Keyword(s):  
Triple Therapy ◽  
Mononuclear Cells ◽  
Linear Regression Analysis ◽  
Plasma Concentrations ◽  
Kinetic Studies ◽  
Pharmacokinetic Data ◽  
Nucleotide Polymorphisms ◽  
Allelic Discrimination ◽  
Peripheral Blood Mononuclear ◽  
Drug Kinetic

PURPOSE: Triple therapy for HCV-1 infection consists in boceprevir or telaprevir, ribavirin and PEG-interferon. Telaprevir is a P-glycoprotein substrate and it is metabolized by CYP3A4/5. No data have been published on intracellular penetration of telaprevir. We determined peripheral blood mononuclear cells (PBMCs) and trough plasma S and R telaprevir isomers concentrations; moreover, we evaluated the influence of some single nucleotide polymorphisms (SNPs) on these pharmacokinetic data after 1 month of triple therapy in humans. METHODS: Plasma and intracellular telaprevir concentrations were determined at the end of dosing interval (Ctrough) using ULPC-MS/MS validated methods; allelic discrimination was performed through real-time PCR. RESULTS: Median telaprevir Ctrough plasma concentrations were 2579 ng/mL and 2233 ng/mL for the pharmacologically more active S, and R, enantiomers, respectively, with median S/R plasma ratio of 1.11. In PBMC, the medians were 6863 ng/mL and 1096 ng/mL for S and R, respectively, with median S/R being 5.73. The PBMC:plasma ratio for S was 2.59 for R. Plasma ribavirin concentrations were directly correlated with plasma S-telaprevir concentrations. In linear regression analysis, only CYP24A1_rs2585428 SNP (p=0.003) and body mass index (p=0.038) were able to predict S-telaprevir PBMC concentrations. CONCLUSIONS: Our preliminary data could increase the understanding of mechanisms underlying telaprevir intracellular and plasma exposure, suggesting the implementation of pharmacogenetics in these drug kinetic studies. This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.

scholarly journals Clinic Design and Continuity in Internal Medicine Resident Clinics: Findings of the Educational Innovations Project Ambulatory Collaborative

2015 ◽  
Vol 7 (1) ◽  
pp. 36-41 ◽  
Author(s):  
Maureen D. Francis ◽  
Mark L. Wieland ◽  
Sean Drake ◽  
Keri Lyn Gwisdalla ◽  
Katherine A. Julian ◽  
...  
Keyword(s):  
Internal Medicine ◽  
Linear Regression Analysis ◽  
Internal Medicine Resident ◽  
Cross Sectional Study ◽  
Analysis Of Covariance ◽  
Block Model ◽  
Cross Sectional ◽  
Educational Innovations ◽  
Medicine Resident ◽  
Multivariable Linear Regression Analysis

Abstract Background Many internal medicine (IM) programs have reorganized their resident continuity clinics to improve trainees' ambulatory experience. Downstream effects on continuity of care and other clinical and educational metrics are unclear. Methods This multi-institutional, cross-sectional study included 713 IM residents from 12 programs. Continuity was measured using the usual provider of care method (UPC) and the continuity for physician method (PHY). Three clinic models (traditional, block, and combination) were compared using analysis of covariance. Multivariable linear regression analysis was used to analyze the effect of practice metrics and clinic model on continuity. Results UPC, reflecting continuity from the patient perspective, was significantly different, and was highest in the block model, midrange in combination model, and lowest in the traditional model programs. PHY, reflecting continuity from the perspective of the resident provider, was significantly lower in the block model than in combination and traditional programs. Panel size, ambulatory workload, utilization, number of clinics attended in the study period, and clinic model together accounted for 62% of the variation found in UPC and 26% of the variation found in PHY. Conclusions Clinic model appeared to have a significant effect on continuity measured from both the patient and resident perspectives. Continuity requires balance between provider availability and demand for services. Optimizing this balance to maximize resident education, and the health of the population served, will require consideration of relevant local factors and priorities in addition to the clinic model.

Ligand effects upon the reactions of Ni(II) with sodium tetrahydroborate: Ni(I) complexes of bipyridyl and 1,10-phenanthroline

1977 ◽  
Vol 55 (23) ◽  
pp. 4048-4055 ◽  
Author(s):  
David G. Holah ◽  
Alan N. Hughes ◽  
Benjamin C. Hui
Keyword(s):  
Electron Transfer ◽  
New Species ◽  
Sodium Tetrahydroborate ◽  
Outer Sphere ◽  
Donor Ligands ◽  
Rapid Reduction ◽  
Electron Transfer Mechanism ◽  
Ligand Effects ◽  
Coordination Sites ◽  
Citrate Reduction

The reactions between NaBH4 and Ni(II) have been studied in the presence of a variety of ligands in an effort to determine (a) the conditions under which reduction occurs, (b) the extent of the reduction (e.g. to Ni(I), Ni(0) complexes, or to Ni metal or boride), and (c) whether intermediate Ni complexes can be isolated.With ligands having no π-bonding capabilities (NH3, ethylenediamine, edta, citrate), reduction depends upon the Ni:ligand ratio and, in the presence of an excess of the ligand, reduction of Ni(II) is very slow. When vacant coordination sites exist on the metal through dissociation of, for example, Ni(NH3)62+, allowing for the interaction of the BH4 group with the metal, then rapid reduction to the metal (or boride) takes place.With the π-bonding N-donor ligands 1,10-phenanthroline (phen) and 2,2′-bipyridyl (bipy) reduction of the stable ML32+ complexes probably occurs via an outer-sphere electron transfer mechanism but, in these cases, new species of the type NiL2X (L = phen, bipy; X = BH4, PF6, BPh4), which formally contain Ni(I), have been isolated.

Cycloaddition of CO2 with epoxides and esterification reactions using the porous redox catalyst Co-POM@MIL-101(Cr)

2019 ◽  
Vol 43 (39) ◽  
pp. 15585-15595 ◽  
Author(s):  
Afsaneh Marandi ◽  
Mehrnaz Bahadori ◽  
Shahram Tangestaninejad ◽  
Majid Moghadam ◽  
Valiollah Mirkhani ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Acetic Acid ◽  
Catalytic Activity ◽  
Outer Sphere ◽  
Transfer Mechanism ◽  
Solvent Free ◽  
Electron Transfer Mechanism ◽  
Redox Catalyst ◽  
Redox Pair ◽  
Esterification Reactions

The catalytic activity of the Co-POM@MIL-101(Cr) composite in solvent-free cycloaddition of CO2 to epoxides and esterification of acetic acid with alcohols is due to an outer-sphere electron transfer mechanism using the Co(iii)/Co(ii) redox pair.

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