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We report the results of the investigation of bulk and surface acoustic phonons in the undoped and boron-doped single-crystal diamond films using the Brillouin-Mandelstam light scattering spectroscopy. The evolution of the optical phonons in the same set of samples was monitored with Raman spectroscopy. It was found that the frequency and the group velocity of acoustic phonons decrease nonmonotonically with the increasing boron doping concentration, revealing pronounced phonon softening. The change in the velocity of the shear-horizontal and the high-frequency pseudo-longitudinal acoustic phonons in the degenerately doped diamond, as compared to that in the undoped diamond, was as large as ∼15% and ∼12%, respectively. As a result of boron doping, the velocity of the bulk longitudinal and transverse acoustic phonons decreased correspondingly. The frequency of the optical phonons was unaffected at low boron concentration but experienced a strong decrease at the high doping level. The density-functional-theory calculations of the phonon band structure for the pristine and highly doped samples confirm the phonon softening as a result of boron doping in diamond. The obtained results have important implications for thermal transport in heavily doped diamond, which is a promising material for ultra-wide-band-gap electronics.

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Amidst a global pandemic, a precise and widely accessible rapid detection method is needed for accurate diagnosis and contact tracing. The lack of this technology was exposed through the outbreak of SARS-CoV-2 beginning in 2019. This study sets the foundation for the development of a boron doped diamond (BDD)-based impedimetric sensor. While specifically developed for use in the detection of SARS-CoV-2, this technology uses principles that could be adapted to detect other viruses in the future. Boron doped polycrystalline diamond electrodes were functionalized with a biotin-streptavidin linker complex and biotinylated anti-SARS-CoV-2 S1 antibodies. Electrodes were then incubated with the S1 subunit of the SARS-CoV-2 spike surface protein, and an electrical response was recorded using the changes to the electrode's charge transfer resistance (Rct), measured through electrochemical impedance spectroscopy (EIS). Detectable changes in the Rct were observed after 5-min incubation periods with S1 subunit concentrations as low as 1 fg/mL. Incubation with Influenza-B Hemagglutinin protein resulted in minimal change to the Rct, indicating specificity of the BDD electrode for the S1 subunit of SARS-CoV-2. Detection of the S1 subunit in a complex (cell culture) medium was also demonstrated by modifying the EIS protocol to minimize the effects of sample matrix binding. BDD films of varying surface morphologies were investigated, and material characterization was used to give insight into the microstructure-performance relationship of the BDD sensing surface.

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In the title compound, [Zn(N(3))(2)(C(10)H(9)N(3))](n), tetra-hedrally coordinated Zn(II) ions with two monodentate azide ligands are linked into zigzag one-dimensional chain motifs by di-4-pyridylamine (dpa) tethers. Individual [Zn(N(3))(2)(dpa)](n) chains are connected into supra-molecular layers via N-H⋯N hydrogen bonding between the central amine groups of the dpa ligands and terminal unligated azide N atoms. The azide ligands in one supra-molecular layer penetrate through the neighboring layers above and below, allowing stacking into a three-dimensional structure.

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In the title compound, [ZnCl(2)(C(16)H(20)N(4))](n), tetra-hedrally coordinated divalent Zn atoms are ligated by two Cl atoms and two N-donor atoms from two 1,4-bis-(3-pyridylmeth-yl)-piperazine (3-bpmp) ligands. The tethering 3-bpmp ligands promote the formation of [ZnCl(2)(3-bpmp)](n) chains situated parallel to (02). These chains aggregate via C-H⋯Cl inter-actions to form supra-molecular layers, which in turn stack to construct the three-dimensional crystal structure.

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OBJECTIVE: We sought to assess whether either a low-cost educational intervention or small monetary incentive is more effective than usual care in lowering low-density lipoprotein (LDL) cholesterol among employees. METHODS: Employees with an LDL-C >130 mg/dL were eligible. After receiving on-line educational materials, subjects were assigned to three groups: group 1 received dollar 100 if they reduced their LDL-C by 15% within 6 months, group 2 participated in a multi-disciplinary educational program, and group 3 received no further intervention. RESULTS: In total, 171 employees participated. Baseline mean LDL-C was 156 mg/dL. Approximately 6 months after randomization, mean LDL-C was reduced 17.9 mg/dL (11.3%) in group 1, 17.9 mg/dL (11.5%) in group 2, and 5.5 mg/dL (3.5%) in group 3. Reductions in groups 1 and 2 were statistically superior to group 3 (P = 0.02). CONCLUSIONS: Both an employer directed low-cost educational program and small monetary incentives similarly lowered LDL-C compared with usual care.

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INTRODUCTION: The purpose of this study is to determine if the Washoe County School District Wellness Program impacted employee health care costs and rates of absenteeism over a 2-year period. METHODS: Outcome variables included health care costs and absenteeism during 2001-2002. Data were collected on 6246 employees over a 6-year period from 1997-2002. Baseline health claims costs and absenteeism from 1997-2000, age, gender, job classification, and years worked at the school district were treated as covariates. Logistic regression was used to compare 2-year costs and absenteeism rates between nonparticipants and employees who participated for 1 and 2 years. RESULTS: No significant differences in health care costs were found between those who participated in any of the wellness programs and those who did not participate. There was a significant negative association between participation and absenteeism; program participants averaged three fewer missed workdays than those who did not participate in any wellness programs. The decrease in absenteeism translated into a cost savings of 15.60 US dollars for every dollar spent on the program. CONCLUSIONS: After controlling for several confounding variables, wellness program participation was associated with large reductions in employee absenteeism.

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