Piecing Together Roman Life and Art: The Impact of Societal Changes on Developments in Roman Mosaics

Although changes in mosaics in ancient Rome can be attributed to various factors such as available resources, skills of the mosaicists, and room aesthetics with wall paintings, the changes in the relationship amongst social classes is a factor that is rarely examined, but strongly impacted these development in mosaic styles. First, an analysis of various mosaics from the 2nd century BC-2nd century AD will be given so that there is an understanding of the changes that occurred. From there, reasons for the adaptations of polychrome into black and white will be assessed; focusing the argument on analysis of the effects of sumptuary laws and Augustus’ influence on society during the founding of the Principate. Chapter 3 will examine the spread of black and white mosaics that happened at the end of the 1st century BC and into the first two centuries AD. To argue for this expansion of mosaics, inspecting the commercialization that was occurring within cities such as Rome, Ostia, and Pompeii will prove critical. While the elite had control over cities during the 2nd century BC, it was due to the changes to social classes brought on by sumptuary laws, Augustus’ authority at the beginning of the Empire, and the commercialization occurring within cities that influenced the shift from polychrome mosaics into black and white mosaics and the stylistic spread to insulae of the working class

pH-Independent, 520 mV Open-Circuit Voltages of Si/Methyl Viologen^(2+/+) Contacts Through Use of Radial n^+p-Si Junction Microwire Array Photoelectrodes

The effects of introducing an n^+-doped emitter layer have been evaluated for both planar Si photoelectrodes and for radial junction Si microwire-array photoelectrodes. In contact with the pH-independent, one-electron, outer-sphere, methyl viologen redox system (denoted MV^(2+/+)), both planar and wire array p-Si photoelectrodes yielded open-circuit voltages, V_(oc), that varied with the pH of the solution. The highest V_(oc) values were obtained at pH = 2.9, with V_(oc) = 0.53 V for planar p-Si electrodes and V_(oc) = 0.42 V for vapor−liquid−solid catalyzed p-Si microwire array samples, under 60 mW cm^(−2) of 808 nm illumination. Increases in the pH of the electrolyte produced a decrease in V_(oc) by approximately −44 mV/pH unit for planar electrodes, with similar trends observed for the Si microwire array electrodes. In contrast, introduction of a highly doped, n^+ emitter layer produced V_(oc) = 0.56 V for planar Si electrodes and V_(oc) = 0.52 V for Si microwire array electrodes, with the photoelectrode properties in each system being essentially independent of pH over six pH units (3 < pH < 9). Hence, formation of an n^+ emitter layer not only produced nearly identical photovoltages for planar and Si microwire array photoelectrodes, but decoupled the band energetics of the semiconductor (and hence the obtainable photovoltage) from the value of the redox potential of the solution. The formation of radial junctions on Si microwire arrays thus provides an approach to obtaining Si-based photoelectrodes with high-photovoltages that can be used for a variety of photoelectrochemical processes, including potentially the hydrogen evolution reaction, under various pH conditions, regardless of the intrinsic barrier height and flat-band properties of the Si/liquid contact

Solar Water Splitting Cells

No abstract

Si microwire-array solar cells

Si microwire-array solar cells with Air Mass 1.5 Global conversion efficiencies of up to 7.9% have been fabricated using an active volume of Si equivalent to a 4 μm thick Si wafer. These solar cells exhibited open-circuit voltages of 500 mV, short-circuit current densities (J_(sc)) of up to 24 mA cm^(-2), and fill factors >65% and employed Al_2O_3 dielectric particles that scattered light incident in the space between the wires, a Ag back reflector that prevented the escape of incident illumination from the back surface of the solar cell, and an a-SiN_x:H passivation/anti-reflection layer. Wire-array solar cells without some or all of these design features were also fabricated to demonstrate the importance of the light-trapping elements in achieving a high J_(sc). Scanning photocurrent microscopy images of the microwire-array solar cells revealed that the higher J_(sc) of the most advanced cell design resulted from an increased absorption of light incident in the space between the wires. Spectral response measurements further revealed that solar cells with light-trapping elements exhibited improved red and infrared response, as compared to solar cells without light-trapping elements

Photoelectrochemical Hydrogen Evolution Using Si Microwire Arrays

Arrays of B-doped p-Si microwires, diffusion-doped with P to form a radial n+ emitter and subsequently coated with a 1.5-nm-thick discontinuous film of evaporated Pt, were used as photocathodes for H_2 evolution from water. These electrodes yielded thermodynamically based energy-conversion efficiencies >5% under 1 sun solar simulation, despite absorbing less than 50% of the above-band-gap incident photons. Analogous p-Si wire-array electrodes yielded efficiencies <0.2%, largely limited by the low photovoltage generated at the p-Si/H_2O junction

Hydrogen-evolution characteristics of Ni–Mo-coated, radial junction, n+p-silicon microwire array photocathodes

The photocathodic H_2-evolution performance of Ni–Mo-coated radial n+p junction Si microwire (Si MW) arrays has been evaluated on the basis of thermodynamic energy-conversion efficiency as well as solar cell figures of merit. The Ni–Mo-coated n^(+)p-Si MW electrodes yielded open-circuit photovoltages (V_oc) of 0.46 V, short-circuit photocurrent densities (J_sc) of 9.1 mA cm^(−2), and thermodynamically based energy-conversion efficiencies (η) of 1.9% under simulated 1 Sun illumination. Under nominally the same conditions, the efficiency of the Ni–Mo-coated system was comparable to that of Pt-coated n+p-Si MW array photocathodes (V_oc = 0.44 V, J_sc = 13.2 mA cm^(−2_, η = 2.7%). This demonstrates that, at 1 Sun light intensity on high surface area microwire arrays, earth-abundant electrocatalysts can provide performance comparable to noble-metal catalysts for photoelectrochemical hydrogen evolution. The formation of an emitter layer on the microwires yielded significant improvements in the open-circuit voltage of the microwire-array-based photocathodes relative to Si MW arrays that did not have a buried n^(+)p junction. Analysis of the spectral response and light-intensity dependence of these devices allowed for optimization of the catalyst loading and photocurrent density. The microwire arrays were also removed from the substrate to create flexible, hydrogen-evolving membranes that have potential for use in a solar water-splitting device

Impact of Obesity in Patients with Candida Bloodstream Infections: A Retrospective Cohort Study

© 2020, The Author(s). Background: Candida species are responsible for 15% of bloodstream infections, leading to prolonged hospitalizations and increased mortality. With the rise in obesity, antifungal dosing is unclear. The purpose of this study was to determine differences in clinical outcomes between obese versus non-obese patients with Candida bloodstream infections. Methods: This retrospective cohort included adult patient’s first episode of Candida bloodstream infection treated with ≥ 48 h of antifungal therapy between 1 June 2013 and 31 August 2019. Patients were excluded for: dual systemic antifungal therapy, polymicrobial infections, or chronic candidiasis. The primary outcome was infection-related length of stay. Secondary outcomes included: time to candidemia resolution, 30-day readmission rates, and in-hospital mortality. Results: Eighty patients were included (28 obese; 52 non-obese). Most were male (55%); median age was 54 years. Median BMI and weight were 36.3 kg/m2 and 103 kg versus 20.4 kg/m2 and 61 kg, respectively (p \u3c 0.01). Baseline characteristics were comparable. C. albicans was isolated in 37.5% of cultures and C. glabrata in 30%. Micafungin was utilized empirically in 72.5% of patients; obese patients received definitive micafungin more frequently (57.1% vs. 21.2%; p \u3c 0.01) and were treated longer (13 versus 10 days; p = 0.04). Infection-related length of stay was 19 days in the obese patients and 13 days in the non-obese patients (p = 0.05). Non-obese patients had a shorter duration of candidemia (5 versus 6 days; p = 0.02). In-hospital mortality was numerically higher in obese patients (21.4% versus 13.5%; p = 0.36). There were no differences in 30-day readmissions between groups. Conclusions: Worse clinical outcomes were observed for obese versus non-obese patients. Further clinical research is warranted

Type I Interferons Are Associated with Subclinical Markers of Cardiovascular Disease in a Cohort of Systemic Lupus Erythematosus Patients

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94405/1/Somers_2012_Type_I_Interferons_subclinical_markers.pdf165

Food Matters: Food Insecurity among Pregnant Adolescents and Infant Birth Outcomes

Objectives: The objectives of this study are to: (1) document prevalence of food insecurity among pregnant adolescents; (2) determine if food insecurity is associated with adverse birth outcomes (i.e., lower birth weight, earlier gestational age) among their newborns; and (3) examine whether depressive symptoms, anxiety, nutrition and/or weight gain mediate these associations. Methods: Pregnant adolescents (14-21 years old; N-881) in prenatal care at community hospitals and health centers in New York City completed a health and psychosocial survey during second and third trimesters of pregnancy. Birth weight and gestational age were recorded from medical records. Results: Over one-half of the adolescents reported food insecurity. Path analyses demonstrated that food insecurity was associated with lower birth weight and earlier gestational age. Depressive symptoms mediated these associations. Conclusions: Pregnant adolescents experience high rates of food insecurity. Those who were food insecure experienced more depressive symptoms, which in turn predicted adverse birth outcomes. Programs and policies should target these vulnerable children to stem the multi-generational effects of food insecurity