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1.
J Shoulder Elbow Surg ; 33(1): 73-81, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37379964

ABSTRACT

BACKGROUND: Instability after reverse shoulder arthroplasty (RSA) is one of the most frequent complications and remains a clinical challenge. Current evidence is limited by small sample size, single-center, or single-implant methodologies that limit generalizability. We sought to determine the incidence and patient-related risk factors for dislocation after RSA, using a large, multicenter cohort with varying implants. METHODS: A retrospective, multicenter study was performed involving 15 institutions and 24 American Shoulder and Elbow Surgeons members across the United States. Inclusion criteria consisted of patients undergoing primary or revision RSA between January 2013 and June 2019 with minimum 3-month follow-up. All definitions, inclusion criteria, and collected variables were determined using the Delphi method, an iterative survey process involving all primary investigators requiring at least 75% consensus to be considered a final component of the methodology for each study element. Dislocations were defined as complete loss of articulation between the humeral component and the glenosphere and required radiographic confirmation. Binary logistic regression was performed to determine patient predictors of postoperative dislocation after RSA. RESULTS: We identified 6621 patients who met inclusion criteria with a mean follow-up of 19.4 months (range: 3-84 months). The study population was 40% male with an average age of 71.0 years (range: 23-101 years). The rate of dislocation was 2.1% (n = 138) for the whole cohort, 1.6% (n = 99) for primary RSAs, and 6.5% (n = 39) for revision RSAs (P < .001). Dislocations occurred at a median of 7.0 weeks (interquartile range: 3.0-36.0 weeks) after surgery with 23.0% (n = 32) after a trauma. Patients with a primary diagnosis of glenohumeral osteoarthritis with an intact rotator cuff had an overall lower rate of dislocation than patients with other diagnoses (0.8% vs. 2.5%; P < .001). Patient-related factors independently predictive of dislocation, in order of the magnitude of effect, were a history of postoperative subluxations before radiographically confirmed dislocation (odds ratio [OR]: 19.52, P < .001), primary diagnosis of fracture nonunion (OR: 6.53, P < .001), revision arthroplasty (OR: 5.61, P < .001), primary diagnosis of rotator cuff disease (OR: 2.64, P < .001), male sex (OR: 2.21, P < .001), and no subscapularis repair at surgery (OR: 1.95, P = .001). CONCLUSION: The strongest patient-related factors associated with dislocation were a history of postoperative subluxations and having a primary diagnosis of fracture nonunion. Notably, RSAs for osteoarthritis showed lower rates of dislocations than RSAs for rotator cuff disease. These data can be used to optimize patient counseling before RSA, particularly in male patients undergoing revision RSA.


Subject(s)
Arthroplasty, Replacement, Shoulder , Joint Dislocations , Osteoarthritis , Shoulder Joint , Humans , Male , Aged , Female , Arthroplasty, Replacement, Shoulder/adverse effects , Arthroplasty, Replacement, Shoulder/methods , Shoulder Joint/surgery , Retrospective Studies , Treatment Outcome , Osteoarthritis/surgery , Joint Dislocations/surgery , Range of Motion, Articular
2.
PLOS Glob Public Health ; 3(10): e0000892, 2023.
Article in English | MEDLINE | ID: mdl-37906535

ABSTRACT

The COVID-19 pandemic has impacted many facets of human behavior, including human mobility partially driven by the implementation of non-pharmaceutical interventions (NPIs) such as stay at home orders, travel restrictions, and workplace and school closures. Given the importance of human mobility in the transmission of SARS-CoV-2, there have been an increase in analyses of mobility data to understand the COVID-19 pandemic to date. However, despite an abundance of these analyses, few have focused on Sub-Saharan Africa (SSA). Here, we use mobile phone calling data to provide a spatially refined analysis of sub-national human mobility patterns during the COVID-19 pandemic from March 2020-July 2021 in Zambia using transmission and mobility models. Overall, among highly trafficked intra-province routes, mobility decreased up to 52% during the time of the strictest NPIs (March-May 2020) compared to baseline. However, despite dips in mobility during the first wave of COVID-19 cases, mobility returned to baseline levels and did not drop again suggesting COVID-19 cases did not influence mobility in subsequent waves.

3.
J Shoulder Elbow Surg ; 32(12): 2483-2492, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37330167

ABSTRACT

BACKGROUND: Both patient and implant related variables have been implicated in the incidence of acromial (ASF) and scapular spine fractures (SSF) following reverse shoulder arthroplasty (RSA); however, previous studies have not characterized nor differentiated risk profiles for varying indications including primary glenohumeral arthritis with intact rotator cuff (GHOA), rotator cuff arthropathy (CTA), and massive irreparable rotator cuff tear (MCT). The purpose of this study was to determine patient factors predictive of cumulative ASF/SSF risk for varying preoperative diagnosis and rotator cuff status. METHODS: Patients consecutively receiving RSA between January 2013 and June 2019 from 15 institutions comprising 24 members of the American Shoulder and Elbow Surgeons (ASES) with primary, preoperative diagnoses of GHOA, CTA and MCT were included for study. Inclusion criteria, definitions, and inclusion of patient factors in a multivariate model to predict cumulative risk of ASF/SSF were determined through an iterative Delphi process. The CTA and MCT groups were combined for analysis. Consensus was defined as greater than 75% agreement amongst contributors. Only ASF/SSF confirmed by clinical and radiographic correlation were included for analysis. RESULTS: Our study cohort included 4764 patients with preoperative diagnoses of GHOA, CTA, or MCT with minimum follow-up of 3 months (range: 3-84). The incidence of cumulative stress fracture was 4.1% (n = 196). The incidence of stress fracture in the GHOA cohort was 2.1% (n = 34/1637) compared to 5.2% (n = 162/3127) (P < .001) in the CTA/MCT cohort. Presence of inflammatory arthritis (odds ratio [OR] 2.90, 95% confidence interval [CI] 1.08-7.78; P = .035) was the sole predictive factor of stress fractures in GHOA, compared with inflammatory arthritis (OR 1.86, 95% CI 1.19-2.89; P = .016), female sex (OR 1.81, 95% CI 1.20-2.72; P = .007), and osteoporosis (OR 1.56, 95% CI 1.02-2.37; P = .003) in the CTA/MCT cohort. CONCLUSION: Preoperative diagnosis of GHOA has a different risk profile for developing stress fractures after RSA than patients with CTA/MCT. Though rotator cuff integrity is likely protective against ASF/SSF, approximately 1/46 patients receiving RSA with primary GHOA will have this complication, primarily influenced by a history of inflammatory arthritis. Understanding risk profiles of patients undergoing RSA by varying diagnosis is important in counseling, expectation management, and treatment by surgeons.


Subject(s)
Arthritis , Arthroplasty, Replacement, Shoulder , Fractures, Stress , Rotator Cuff Injuries , Shoulder Joint , Female , Humans , Arthritis/surgery , Arthroplasty, Replacement, Shoulder/adverse effects , Fractures, Stress/diagnostic imaging , Fractures, Stress/etiology , Range of Motion, Articular , Retrospective Studies , Risk Factors , Rotator Cuff Injuries/complications , Rotator Cuff Injuries/diagnostic imaging , Rotator Cuff Injuries/surgery , Scapula/diagnostic imaging , Scapula/surgery , Shoulder Joint/diagnostic imaging , Shoulder Joint/surgery , Treatment Outcome , Male
4.
Orthop Clin North Am ; 54(3): 349-358, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37271563

ABSTRACT

The number of spinal operations performed in the United States has significantly increased in recent years. Along with these rising numbers, there has been a corresponding increase in the number of patient comorbidities. The focus of this article is to review comorbidities in Spine surgery patients and outline strategies to optimize patients and avoid complications.


Subject(s)
Postoperative Complications , Spinal Fusion , Humans , United States , Postoperative Complications/epidemiology , Postoperative Complications/prevention & control , Postoperative Complications/etiology , Comorbidity , Retrospective Studies , Spinal Fusion/adverse effects
5.
Int J Mol Sci ; 24(2)2023 Jan 04.
Article in English | MEDLINE | ID: mdl-36674505

ABSTRACT

Cellulose of bacterial origin, known as bacterial cellulose (BC), is one of the most versatile biomaterials that has a huge potential in tissue engineering due to its favourable mechanical properties, high hydrophilicity, crystallinity, and purity. Additional properties such as porous nano-fibrillar 3D structure and a high degree of polymerisation of BC mimic the properties of the native extracellular matrix (ECM), making it an excellent material for the fabrication of composite scaffolds suitable for cell growth and tissue development. Recently, the fabrication of BC-based scaffolds, including composites and blends with nanomaterials, and other biocompatible polymers has received particular attention owing to their desirable properties for tissue engineering. These have proven to be promising advanced materials in hard and soft tissue engineering. This review presents the latest state-of-the-art modified/functionalised BC-based composites and blends as advanced materials in tissue engineering. Their applicability as an ideal biomaterial in targeted tissue repair including bone, cartilage, vascular, skin, nerve, and cardiac tissue has been discussed. Additionally, this review briefly summarises the latest updates on the production strategies and characterisation of BC and its composites and blends. Finally, the challenges in the future development and the direction of future research are also discussed.


Subject(s)
Biocompatible Materials , Tissue Engineering , Biocompatible Materials/chemistry , Cellulose/chemistry , Tissue Scaffolds/chemistry , Polymers , Bacteria/chemistry
6.
Preprint in English | medRxiv | ID: ppmedrxiv-22277849

ABSTRACT

The COVID-19 pandemic has impacted many facets of human behavior, including human mobility partially driven by the implementation of non-pharmaceutical interventions (NPIs) such as stay at home orders, travel restrictions, and workplace and school closures. Given the importance of human mobility in the transmission of SARS-CoV-2, there have been an increase in analyses of mobility data to understand the COVID-19 pandemic to date. However, despite an abundance of these analyses, few have focused on Sub-Saharan Africa (SSA). Here, we use mobile phone calling data to provide a spatially refined analysis of sub-national human mobility patterns during the COVID-19 pandemic from March 2020-July 2021 in Zambia. Overall, among highly trafficked intra-province routes, mobility decreased up to 52% from March-May 2020 compared to baseline, which was also the time period of the strictest NPIs. However, despite dips in mobility during the first wave of COVID-19 cases, mobility returned to baseline levels and did not drop again suggesting COVID-19 cases did not influence mobility in subsequent waves.

7.
Elife ; 102021 09 17.
Article in English | MEDLINE | ID: mdl-34533456

ABSTRACT

Human mobility is a core component of human behavior and its quantification is critical for understanding its impact on infectious disease transmission, traffic forecasting, access to resources and care, intervention strategies, and migratory flows. When mobility data are limited, spatial interaction models have been widely used to estimate human travel, but have not been extensively validated in low- and middle-income settings. Geographic, sociodemographic, and infrastructure differences may impact the ability for models to capture these patterns, particularly in rural settings. Here, we analyzed mobility patterns inferred from mobile phone data in four Sub-Saharan African countries to investigate the ability for variants on gravity and radiation models to estimate travel. Adjusting the gravity model such that parameters were fit to different trip types, including travel between more or less populated areas and/or different regions, improved model fit in all four countries. This suggests that alternative models may be more useful in these settings and better able to capture the range of mobility patterns observed.


Subject(s)
Human Migration/statistics & numerical data , Models, Biological , Rural Population/statistics & numerical data , Africa South of the Sahara/epidemiology , Humans , Spatial Analysis , Travel/statistics & numerical data
9.
Inorg Chem ; 57(12): 7259-7269, 2018 Jun 18.
Article in English | MEDLINE | ID: mdl-29877086

ABSTRACT

Organic ligands with carboxylate functionalities have been shown to affect the solubility, speciation, and overall chemical behavior of tetravalent metal ions. While many reports have focused on actinide complexation by relatively simple monocarboxylates such as amino acids, in this work we examined Th(IV) and U(IV) complexation by 4-hydroxybenzoic acid in water with the aim of understanding the impact that the organic backbone has on the solution and solid state structural chemistry of thorium(IV) and uranium(IV) complexes. Two compounds of the general formula [An6O4(OH)4(H2O)6(4-HB)12]· nH2O [An = Th (Th-1) and U (U-1); 4-HB = 4-hydroxybenzoate] were synthesized via room-temperature reactions of AnCl4 and 4-hydroxybenzoic acid in water. Solid state structures were determined by single-crystal X-ray diffraction, and the compounds were further characterized by Raman, infrared, and optical spectroscopies and thermogravimetry. The magnetism of U-1 was also examined. The structures of the Th and U compounds are isomorphous and are built from ligand-decorated oxo/hydroxo-bridged hexanuclear units. The relationship between the building units observed in the solid state structure of U-1 and those that exist in solution prior to crystallization as well as upon dissolution of U-1 in nonaqueous solvents was investigated using small-angle X-ray scattering, ultraviolet-visible optical spectroscopy, and dynamic light scattering. The evolution of U solution speciation as a function of reaction time and temperature was examined. Such effects as well as the impact of the ligand on the formation and evolution of hexanuclear U(IV) clusters to UO2 nanoparticles compared to prior reported monocarboxylate ligand systems are discussed. Unlike prior reported syntheses of Th and U(IV) hexamers where the pH was adjusted to ∼2 and 3, respectively, to drive hydrolysis, hexamer formation with the HB ligand appears to be promoted only by the ligand.

10.
Phys Chem Chem Phys ; 20(6): 4554-4562, 2018 Feb 07.
Article in English | MEDLINE | ID: mdl-29376165

ABSTRACT

Two isostructural cobalt containing polyoxometalate water oxidation catalysts, [Co4(H2O)2(α-PW9O34)2]10- (Co4P2) and [Co4(H2O)2(α-VW9O34)2]10- (Co4V2), exhibit large differences in their catalytic performance. The substitution of phosphorus centers in Co4P2 with redox-active vanadium centers in Co4V2 leads to electronic structure modifications. Evidence for the significance of the vanadium centers to catalysis, predicted by theory, was found from soft X-ray absorption (XAS) and resonant inelastic X-ray scattering (RIXS). The XAS and RIXS spectra determine the electronic structure of the cobalt and vanadium sites in the pre-reaction state of both Co4V2 and Co4P2. High-energy resolution RIXS results reveal that Co4V2 possesses a smaller ligand field within the tetra-cobalt core and a cobalt-to-vanadium charge transfer band. The differences in electronic structures offer insights into the enhanced catalysis of Co4V2.

11.
Curr Pharm Des ; 24(1): 84-98, 2018.
Article in English | MEDLINE | ID: mdl-27981905

ABSTRACT

Diabetes mellitus (DM) is a highly prevalent condition that causes significant morbidity and mortality in the United States and worldwide. Conventional therapies include lifestyle modification, oral pharmacological agents, and subcutaneous insulin. Emerging data suggest that natural approaches to the treatment of DM may help supplement current therapies for further glycemic control. Herein, we review the evidence of several natural modalities for DM treatment. We describe the pathophysiology of diabetes and its complications, provide an overview of current pharmacologic treatments, and finally, discuss natural approaches to diabetes management. Specifically, we will describe on the utility of diet, physical activity, and common natural products in the treatment of DM and focus on recent, high-quality studies. Adverse effects and potential interactions of each therapy will be highlighted where applicable.


Subject(s)
Biological Products/therapeutic use , Diabetes Mellitus/drug therapy , Exercise , Hypoglycemic Agents/therapeutic use , Animals , Biological Products/administration & dosage , Diabetes Mellitus/physiopathology , Diet , Humans , Hypoglycemic Agents/administration & dosage
12.
Biol Psychiatry ; 84(2): 138-147, 2018 07 15.
Article in English | MEDLINE | ID: mdl-29129318

ABSTRACT

BACKGROUND: The heterogeneity of genetic effects on major depressive disorder (MDD) may be partly attributable to moderation of genetic effects by environment, such as exposure to childhood trauma (CT). Indeed, previous findings in two independent cohorts showed evidence for interaction between polygenic risk scores (PRSs) and CT, albeit in opposing directions. This study aims to meta-analyze MDD-PRS × CT interaction results across these two and other cohorts, while applying more accurate PRSs based on a larger discovery sample. METHODS: Data were combined from 3024 MDD cases and 2741 control subjects from nine cohorts contributing to the MDD Working Group of the Psychiatric Genomics Consortium. MDD-PRS were based on a discovery sample of ∼110,000 independent individuals. CT was assessed as exposure to sexual or physical abuse during childhood. In a subset of 1957 cases and 2002 control subjects, a more detailed five-domain measure additionally included emotional abuse, physical neglect, and emotional neglect. RESULTS: MDD was associated with the MDD-PRS (odds ratio [OR] = 1.24, p = 3.6 × 10-5, R2 = 1.18%) and with CT (OR = 2.63, p = 3.5 × 10-18 and OR = 2.62, p = 1.4 ×10-5 for the two- and five-domain measures, respectively). No interaction was found between MDD-PRS and the two-domain and five-domain CT measure (OR = 1.00, p = .89 and OR = 1.05, p = .66). CONCLUSIONS: No meta-analytic evidence for interaction between MDD-PRS and CT was found. This suggests that the previously reported interaction effects, although both statistically significant, can best be interpreted as chance findings. Further research is required, but this study suggests that the genetic heterogeneity of MDD is not attributable to genome-wide moderation of genetic effects by CT.


Subject(s)
Child Abuse/psychology , Depressive Disorder, Major/genetics , Adult , Adult Survivors of Child Abuse/psychology , Case-Control Studies , Child , Depressive Disorder, Major/epidemiology , Female , Gene-Environment Interaction , Genetic Predisposition to Disease , Humans , Logistic Models , Male , Multifactorial Inheritance , Psychiatric Status Rating Scales , Risk Assessment , Risk Factors
13.
ACS Appl Mater Interfaces ; 9(40): 35048-35056, 2017 Oct 11.
Article in English | MEDLINE | ID: mdl-28929745

ABSTRACT

Fast and earth-abundant-element polyoxometalates (POMs) have been heavily studied recently as water oxidation catalysts (WOCs) in homogeneous solution. However, POM WOCs can be quite unstable when supported on electrode or photoelectrode surfaces under applied potential. This article reports for the first time that a nanoscale oxide coating (Al2O3) applied by the atomic layer deposition (ALD) aids immobilization and greatly stabilizes this now large family of molecular WOCs when on electrode surfaces. In this study, [{RuIV4(OH)2(H2O)4}(γ-SiW10O34)2]10- (Ru4Si2) is supported on hematite photoelectrodes and then protected by ALD Al2O3; this ternary system was characterized before and after photoelectrocatalytic water oxidation by Fourier transform infrared, X-ray photoelectron spectroscopy, energy-dispersive X-ray, and voltammetry. All these studies indicate that Ru4Si2 remains intact with Al2O3 ALD protection, but not without. The thickness of the Al2O3 layer significantly affects the catalytic performance of the system: a 4 nm thick Al2O3 layer provides optimal performance with nearly 100% faradaic efficiency for oxygen generation under visible-light illumination. Al2O3 layers thicker than 6.5 nm appear to completely bury the Ru4Si2 catalyst, removing all of the catalytic activity, whereas thinner layers are insufficient to maintain a long-term attachment of the catalytic POM.

14.
Cardiovasc Endocrinol ; 6(4): 128-135, 2017 Dec.
Article in English | MEDLINE | ID: mdl-31646130

ABSTRACT

Type 2 diabetes mellitus (DM) is a significant cause of premature complications and mortality in patients with cardiovascular disease (CVD). In addition to lifestyle modifications, conventional treatment of DM consists of oral hypoglycemic agents, insulin sensitizers, and subcutaneous insulin. In diabetic individuals with or at risk for CVD, aspirin and statin therapy reduce CVD morbidity and mortality. Several natural or herbal supplements have shown potential benefit in patients with CVD and DM. We provide an overview of the current guidelines for treatment of DM and CVD. We then review the literature to describe the efficacy of natural approaches to CVD risk reduction in diabetic patients, with a focus on physical activity, dietary modification, and natural/herbal supplements. Activity and diet improve cardiovascular outcomes in patients with CVD and DM. Natural and herbal supplements have potential for benefit but require further research to determine their efficacy and safety.

15.
Anim Genet ; 48(2): 237-241, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27699807

ABSTRACT

Farmed Atlantic salmon (Salmo salar) is a globally important production species, including in Australia where breeding and selection has been in progress since the 1960s. The recent development of SNP genotyping platforms means genome-wide association and genomic prediction can now be implemented to speed genetic gain. As a precursor, this study collected genotypes at 218 132 SNPs in 777 fish from a Tasmanian breeding population to assess levels of genetic diversity, the strength of linkage disequilibrium (LD) and imputation accuracy. Genetic diversity in Tasmanian Atlantic salmon was lower than observed within European populations when compared using four diversity metrics. The distribution of allele frequencies also showed a clear difference, with the Tasmanian animals carrying an excess of low minor allele frequency variants. The strength of observed LD was high at short distances (<25 kb) and remained above background for marker pairs separated by large chromosomal distances (hundreds of kb), in sharp contrast to the European Atlantic salmon tested. Genotypes were used to evaluate the accuracy of imputation from low density (0.5 to 5 K) up to increased density SNP sets (78 K). This revealed high imputation accuracies (0.89-0.97), suggesting that the use of low density SNP sets will be a successful approach for genomic prediction in this population. The long-range LD, comparatively low genetic diversity and high imputation accuracy in Tasmanian salmon is consistent with known aspects of their population history, which involved a small founding population and an absence of subsequent introgression. The findings of this study represent an important first step towards the design of methods to apply genomics in this economically important population.


Subject(s)
Aquaculture , Salmo salar/genetics , Animals , Female , Gene Frequency , Linkage Disequilibrium , Male , Polymorphism, Single Nucleotide , Tasmania
16.
Can J Cardiol ; 32(10 Suppl 2): S349-S357, 2016 10.
Article in English | MEDLINE | ID: mdl-27692115

ABSTRACT

The epidemic of obesity has contributed to a growing burden of metabolic syndrome (MetS) and diabetes mellitus (DM) worldwide. MetS is defined as central obesity along with associated factors such as hypertriglyceridemia, low high-density lipoprotein cholesterol, hyperglycemia, and hypertension. MetS and DM are associated with significant cardiovascular morbidity and mortality. Healthy behavioural modification is the cornerstone for reducing the atherosclerotic cardiovascular disease burden in this population. Comprehensive, multidisciplinary cardiac rehabilitation (CR) programs reduce mortality and hospitalizations in patients with MetS and DM. Despite this benefit, patients with MetS and DM are less likely to attend and complete CR because of numerous barriers. Implementation of innovative CR delivery models might improve utilization of CR and cardiovascular outcomes in this high-risk population.


Subject(s)
Cardiac Rehabilitation , Cardiovascular Diseases/prevention & control , Diabetes Complications , Metabolic Syndrome/complications , Obesity/complications , Cardiovascular Diseases/etiology , Clinical Trials as Topic , Diet, Mediterranean , Exercise , Hospitalization , Humans , Risk Reduction Behavior
17.
Inorg Chem ; 55(20): 10152-10160, 2016 Oct 17.
Article in English | MEDLINE | ID: mdl-27673751

ABSTRACT

The Co 2p3/2 X-ray absorption spectroscopy and high-energy-resolution (∼0.09 eV fwhm) 2p3d resonant inelastic X-ray scattering (RIXS) spectra of the single-cobalt-centered polyoxometalate K5H[CoW12O40]·xH2O were measured. The low-energy dd transition features at 0.55 eV, unmeasurable with ultraviolet-visible (UV/vis) spectroscopy, were experimentally revealed in 2p3d RIXS spectra. RIXS simulations based on ligand-field multiplet theory were performed to assess the potential cobalt tetragonal symmetry distortion, which is described with the ligand-field parameters 10Dq (-0.54 eV), Ds (-0.08 eV), and Dt (0.005 eV). Because 2p3d RIXS probes not only the optical spin-allowed transitions but also the spin-forbidden transitions, we show that the current 2p3d RIXS simulation enables a series of dd feature assignments with higher accuracy than those from previous optical data. Furthermore, by wave-function decomposition analyses, we demonstrate the more realistic and detailed origins of a few lowest dd transitions using both one-electron-orbital and term-symbol descriptions.

18.
Inorg Chem ; 55(9): 4308-19, 2016 05 02.
Article in English | MEDLINE | ID: mdl-27082443

ABSTRACT

A series of hetero-bimetallic transition metal-substituted polyoxometalates (TMSPs) were synthesized based on the Co(II)-centered ligand [Co(II)W11O39](10-). The eight complex series, [Co(II)(M(x)OHy)W11O39]((12-x-y)-) (M(x)OHy = V(IV)O, Cr(III)(OH2), Mn(II)(OH2), Fe(III)(OH2), Co(II)(OH2), Ni(II)(OH2), Cu(II)(OH2), Zn(II)(OH2)), of which six are reported for the first time, was synthesized starting from [Co(III)W11O39](9-) and studied using spectroscopic, electrochemical, and computational techniques to evaluate the influence of substituted transition metals on the photodynamics of the metal-to-polyoxometalate charge transfer (MPCT) transition. The bimetallic complexes all show higher visible light absorption than the plenary [Co(II)W12O40](6-) and demonstrate the same MPCT transition as the plenary complex, but they have shorter excited-state lifetimes (sub-300 ps in aqueous media). The decreased lifetimes are rationalized on the basis of nonradiative relaxation due to coordinating aqua ligands, increased interaction with cations due to increased negative charge, and the energy gap law, with the strongest single factor appearing to be the charge on the anion. The most promising results are from the Cr- and Fe-substituted systems, which retain excited-state lifetimes at least 50% of that of [Co(II)W12O40](6-) while more than tripling the absorbance at 400 nm.


Subject(s)
Coordination Complexes/chemistry , Metals, Heavy/chemistry , Oxides/chemistry , Cobalt/chemistry , Coordination Complexes/chemical synthesis , Crystallography, X-Ray , Electrochemical Techniques , Kinetics , Light , Models, Chemical , Molecular Structure , Oxides/chemical synthesis , Spectrophotometry, Infrared , Tungsten/chemistry
19.
Benefits Q ; 31(4): 13-21, 2015.
Article in English | MEDLINE | ID: mdl-26666087

ABSTRACT

One of the options available to employers under the Affordable Care Act is to drop health care coverage, pay a penalty and provide some form of additional compensation to employees. This article describes a process for evaluating this option, including considerations for establishing the amount of compensation to be provided, if any. It identifies a number of complexities and provides hypothetical examples of how employers might apply this option to employees with different salaries, ages and family statuses.


Subject(s)
Choice Behavior , Health Benefit Plans, Employee/economics , Insurance Coverage/organization & administration , Salaries and Fringe Benefits/economics , United States
20.
Benefits Q ; 31(1): 43-50, 2015.
Article in English | MEDLINE | ID: mdl-26540943

ABSTRACT

Employers have been afforded new opportunities with the enactment of the Affordable Care Act (ACA). ACA creates a unique opportunity for employers to take a fresh, strategically based total compensation approach to planning. The concept of a total compensation framework is not new; however, a new way to achieve this approach is now possible. Employers need to create their own level playing field, and a total compensation approach is the optimal solution. This article discusses how employers that consider a framework driven toward total compensation accomplish many key objectives.


Subject(s)
Health Benefit Plans, Employee/economics , Patient Protection and Affordable Care Act , Personnel Management/economics , Retirement/economics , Salaries and Fringe Benefits/economics , Humans , Planning Techniques , United States
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