To understand increasing rates of hepatitis C virus (HCV) infection in Tennessee, we conducted testing, risk factor analysis and a nested case–control study among persons who use drugs. During June–October 2016, HCV testing with risk factor assessment was conducted in sexually transmitted disease clinics, family planning clinics and an addiction treatment facility in eastern Tennessee; data were analysed by using multivariable logistic regression. A nested case–control study was conducted to assess drug-using risks and behaviours among persons who reported intranasal or injection drug use (IDU). Of 4753 persons tested, 397 (8.4%) were HCV-antibody positive. HCV infection was significantly associated with a history of both intranasal and IDU (adjusted odds ratio (aOR) 35.4, 95% confidence interval (CI) 24.1–51.9), IDU alone (aOR 52.7, CI 25.3–109.9), intranasal drug use alone (aOR 2.6, CI 1.8–3.9) and incarceration (aOR 2.7, CI 2.0–3.8). By 4 October 2016, 574 persons with a reported history of drug use; 63 (11%) were interviewed further. Of 31 persons who used both intranasal and injection drugs, 26 (84%) reported previous intranasal drug use, occurring 1–18 years (median 5.5 years) before their first IDU. Our findings provide evidence that reported IDU, intranasal drug use and incarceration are independent indicators of risk for past or present HCV infection in the study population.

We conducted a systematic review to examine the relationship between intracranial pressure monitors (ICP) monitors and mortality in traumatic brain injury (TBI). We systematically searched for articles that met the following criteria: (1) adults patients, (2) TBI, (3) use of an ICP monitor, (4) point estimate for mortality with ICP monitoring (5) adjustment for potential confounders. Six observational studies were identified with 11,371 patients. There was marked between-study heterogeneity that precluded a pooled analysis. Patients with ICP monitors had different clinical characteristics and received more ICP targeted therapy in the ICU. Four studies found no significant relationship between ICP monitoring and survival, while the other two studies demonstrated conflicting results. Significant confounding by indication in observational studies limits the examination of isolated TBI interventions. More research should focus on interventions that affect TBI careplan systems. Further research is needed to identify which subset of severe TBI patients may benefit from ICP monitoring.

Conductive tin-oxide (SnO2) film is doped by group V or VII elements. Of all possible dopants, fluorine provides n-type SnO2 with the best electronic and optical properties. However, the commonly used fluorine dopant, bromotrifluoromethane (CBrF3), is a greenhouse gas. Thus, an alternative fluorine source is needed. In this work, we compared CIF3 as a fluorine dopant to CBrF3. With CBrF3 dopant, optimized carrier concentration and electron mobility values can reach to mid 1020 cm-3 and over 40 cm2/V-s, respectively. After carrier concentration saturates, the electronic mobility continues to improve with an increase of CBrF3 dopant concentration. As a comparison, to achieve similar carrier concentration, far less CIF3 dopant is required. However, the electron mobility is lower (<30 cm2/V-s) and does not improve with an increase of dopant concentration. The low electron mobility increases the optical absorption, especially of long wavelengthes. Considering CdTe/CdS solar cell efficiency, the device with a CIF3-doped SnO2 window layer provides the lower photocurrent.

The present model for current transport at the CdTe/p-ZnTe:Cu/metal back contact assumes that the CdTe and ZnTe valence bands align, while current transport at a highly doped ZnTe and a metal interface proceeds by tunneling. To test part of this model, we have investigated the electrical and material properties of CdS/CdTe devices where the outer metal is either Ti or Ni. Our results show that differences in device series resistance are not linked simply to metal/ZnTe:Cu interfacial contact resistance, but that metallization-induced diffusion remains a more likely cause of significant performance distinctions.

Graded-band-gap CuIn1−xGaxSe2 (CIGS) absorbers with Ga/Ga+In value in the 20%-30% range have a demonstrated efficiency of 18.8%. For CdS-containing devices, the shortcircuit current density (Jsc) has almost reached its expected maximum. However, the open-circuit voltage of CIGS solar cells is limited by the surface microstructure and chemistry. In this work, we examine the microstructural properties and chemistry of CIGS. We also attempted to correlate the above observations and device performance.

A study of the CdS/CdTe interface was performed on glass/SnO2/CdS/CdTe device structures. CdS layers were deposited by chemical solution growth to a thickness of 80–100 nm, and CdTe was deposited by close-spaced sublimation at substrate temperatures of 500°, 550°, and 600°C. Post-deposition CdCl2 heat treatment was performed at 400°C. Samples were analyzed by optical spectroscopy, secondary ion mass spectrometry (SIMS), spectral response, and current-voltage measurements. SIMS analysis shows that the intermixing of CdS and CdTe is a function of substrate temperature and post-deposition CdCl2 heat treatment. The degree of intermixing increases with increases in substrate temperature and the intensity of CdCl2 heat treatment. Optical analysis and X-Ray diffraction data show that the phases of CdSxTe1-x are also a function of the same parameters. Formation of a Te-rich CdSxTe1-x alloy is favored for films deposited at higher substrate temperatures. Spectral response of the devices is affected by the degree of alloying at the interface. The degree of alloying is indicated by simultaneous changes in long wavelength response (due to the formation of lower bandgap intermixed CdSxTe1-x) and the short wavelength response (due to the change in CdS thickness). Device performance is heavily influenced by alloying at the interface. With optimized intermixing, improvements in Voc, and diode quality factors are observed in the resulting devices.

Silicon core and valence levels were studied in hydrogenated amorphous silicon (a-Si:H) as a function of hydrogen concentration. The techniques used to establish the core levels were X-ray Photoelectron Spectroscopy and core-level Electron Energy Loss Spectroscopy. Changes in the local densities of states of the silicon 3s and 3p levels were examined with Auger Electron Spectroscopy. The a-Si:H samples were grown by RF sputtering. Their hydrogen concentrations varied from zero to nearly fifteen percent.