Publications

ABSTRACT Early exposure to multiple risk factors has been shown to predict criminal offending, but the mechanisms responsible for this association are poorly understood. Integrating social‐environmental and dispositional theories of crime this research investigated the capacity of family socioeconomic disadvantage and individual psychological deficits to mediate the association between childhood cumulative risk and late adolescent criminal convictions. Male participants in the 1986 Northern Finland Birth Cohort Study (n = 3414) were followed from the prenatal period through age 19–20. The data were analyzed by estimating a structural equation model of the hypothesized pathways. The results found support for both processes of influence, and the model sustained a statistically significant direct effect of cumulative risk on crime. Socioeconomic disadvantage and psychological deficits contribute to criminal offending independently and with roughly equal magnitude. The results point to the utility of both environmental and psychological interventions to prevent criminality among children at risk.

Abstract Background Evidence on the comprehensive role of lifestyle in frailty risk is scarce. To assess the association between a lifestyle-based Healthy Heart Score (HHS), which estimates the 20-year risk of cardiovascular disease (CVD), and risk of frailty among older women. Methods Prospective cohort study in 121,700 nurses from the USA participating at the Nurses’ Health Study. This study included 68,416 women aged ≥60 year with a follow-up from 1990 to 2014. The HHS was computed using the gender-specific beta-coefficients of the nine lifestyle factors, including current smoking, high body mass index, low physical activity, lack of moderate alcohol intake and unhealthy diet. Frailty incidence was assessed every 4 years from 1992 to 2014 as having ≥3 of the following five criteria from the FRAIL scale: fatigue, low strength, reduced aerobic capacity, having ≥5 illnesses and weight loss ≥5%. Results During 22 years of follow-up, 11,041 total incident cases of frailty were ascertained. Compared to women in the lowest quintile of the HHS (lowest estimated CVD risk), the multivariable-adjusted hazard ratio of frailty across quintiles was: Q2:1.67 (95% confidence interval 1.53, 1.82); Q3: 2.34 (2.15, 2.53); Q4: 3.54 (3.28, 3.83) and Q5: 5.92 (5.48, 6.38); P-trend > 0.001. Results were consistent for each frailty criterion, among participants with 0 frailty criteria at baseline, when using only baseline exposure or in 6-year-, 10-year- and 14-year-exposure lagged analyses, and after excluding participants with diabetes and CVD at baseline. Conclusions The HHS, based on a set of modifiable-lifestyle factors, is strongly associated with risk of frailty in older women.

Abstract Background Greater maternal adiposity before or during pregnancy is associated with greater offspring adiposity throughout childhood, but the extent to which this is due to causal intrauterine or periconceptional mechanisms remains unclear. Here, we use Mendelian randomisation (MR) with polygenic risk scores (PRS) to investigate whether associations between maternal pre-/early pregnancy body mass index (BMI) and offspring adiposity from birth to adolescence are causal. Methods We undertook confounder adjusted multivariable (MV) regression and MR using mother-offspring pairs from two UK cohorts: Avon Longitudinal Study of Parents and Children (ALSPAC) and Born in Bradford (BiB). In ALSPAC and BiB, the outcomes were birthweight (BW; N = 9339) and BMI at age 1 and 4 years ( N = 8659 to 7575). In ALSPAC only we investigated BMI at 10 and 15 years ( N = 4476 to 4112) and dual-energy X-ray absorptiometry (DXA) determined fat mass index (FMI) from age 10–18 years ( N = 2659 to 3855). We compared MR results from several PRS, calculated from maternal non-transmitted alleles at between 29 and 80,939 single nucleotide polymorphisms (SNPs). Results MV and MR consistently showed a positive association between maternal BMI and BW, supporting a moderate causal effect. For adiposity at most older ages, although MV estimates indicated a strong positive association, MR estimates did not support a causal effect. For the PRS with few SNPs, MR estimates were statistically consistent with the null, but had wide confidence intervals so were often also statistically consistent with the MV estimates. In contrast, the largest PRS yielded MR estimates with narrower confidence intervals, providing strong evidence that the true causal effect on adolescent adiposity is smaller than the MV estimates ( P difference = 0.001 for 15-year BMI). This suggests that the MV estimates are affected by residual confounding, therefore do not provide an accurate indication of the causal effect size. Conclusions Our results suggest that higher maternal pre-/early-pregnancy BMI is not a key driver of higher adiposity in the next generation. Thus, they support interventions that target the whole population for reducing overweight and obesity, rather than a specific focus on women of reproductive age.

The control of pneumatically driven soft robots typically requires electronics. Microcontrollers are connected to power electronics that switch valves and pumps on and off. As a recent alternative, fluidic control methods have been introduced, in which soft digital logic gates permit multiple actuation states to be achieved in soft systems. Such systems have demonstrated autonomous behaviors without the use of electronics. However, fluidic controllers have required complex fabrication processes. To democratize the exploration of fluidic controllers, we developed tube-balloon logic circuitry, which consists of logic gates made from straws and balloons. Each tube-balloon logic device takes a novice five minutes to fabricate and costs $0.45. Tube-balloon logic devices can also operate at pressures of up to 200 kPa and oscillate at frequencies of up to 15 Hz. We configure the tube-balloon logic device as NOT-, NAND-, and NOR-gates and assemble them into a three-ring oscillator to demonstrate a vibrating sieve that separates sugar from rice. Because tube-balloon logic devices are low-cost, easy to fabricate, and their operating principle is simple, they are well suited for exploring fundamental concepts of fluidic control schemes while encouraging design inquiry for pneumatically driven soft robots

Olive oil is the foremost source of fat in the Mediterranean area and, among other features, sets the Mediterranean diet apart from other dietary regimens. In January 2018, the International Olive Council convened several worldwide experts at the Robert Mondavi Institute (Davis, CA), to discuss and summarize the available data on the effects of olive oil consumption on human health. In this paper, we critically provide a synthesis of the main reported findings, which underscore how and why consuming this oil as part of a balanced diet and healthful lifestyle improves prognosis and extends life- and health-spans.

A general approach for the synthesis of manganese-doped II−VI and III−V nanowires based on metal nanocluster-catalyzed chemical vapor deposition has been developed. High-resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy studies of Mn-doped CdS, ZnS, and GaN nanowires demonstrate that the nanowires are single-crystal structures and homogeneously doped with controllable concentrations of manganese ions. Photoluminescence measurements of individual Mn-doped CdS and ZnS nanowires show characteristic pseudo-tetrahedral Mn2+ (4T1 → 6A1) transitions that match the corresponding transitions in bulk single-crystal materials well. Photoluminescence studies of Mn-doped GaN nanowires suggest that manganese is incorporated as a neutral (Mn3+) dopant that partially quenches the GaN band-edge emission. The general and controlled synthesis of nanowires doped with magnetic metal ions opens up opportunities for fundamental physical studies and could lead to the development of nanoscale spintronic devices.

This paper describes the influence of the substitution of fluorine for hydrogen on the rate of charge transport by hole tunneling through junctions of the form Ag(TS)O2C(CH2)n(CF2)(m)T//Ga2O3/EGaIn, where T is methyl (CH3) or trifluoromethyl (CF3). Alkanoate-based self-assembled monolayers (SAMs) having perfluorinated groups (R(F)) show current densities that are lower (by factors of 20-30) than those of the homologous hydrocarbons (R(H)), while the attenuation factors of the simplified Simmons equation for methylene (β = (1.05 ± 0.02)n(CH2)(-1)) and difluoromethylene (β = (1.15 ± 0.02)n(CF2)(-1)) are similar (although the value for (CF2)n is statistically significantly larger). A comparative study focusing on the terminal fluorine substituents in SAMs of ω-tolyl- and -phenyl-alkanoates suggests that the C-F//Ga2O3 interface is responsible for the lower tunneling currents for CF3. The decrease in the rate of charge transport in SAMs with R(F) groups (relative to homologous R(H) groups) is plausibly due to an increase in the height of the tunneling barrier at the T//Ga2O3 interface, and/or to weak van der Waals interactions at that interface.

This paper characterizes the complexes formed by a small protein, ubiquitin (UBI), and a negatively charged surfactant, sodium dodecyl sulfate (SDS), using capillary electrophoresis (CE), circular dichroism (CD), and amide hydrogen-deuterium exchange (HDX; as monitored by mass spectroscopy, MS). Capillary electrophoresis of complexes of UBI and SDS, at apparent equilibrium, at concentrations of SDS ranging from sub-micellar and sub-denaturing to micellar and denaturing, revealed multiple complexes of UBI and SDS of the general composition UBI-SDS(n). Examination of electrophoretic mobilities of complexes of UBI and SDS as a function of the concentration of SDS provided a new way to characterize the interaction of this protein with SDS and established key characteristics of this system: e.g., the reversibility of the formation of the complexes, their approximate chemical compositions, and the pathway of SDS binding to UBI. The work identified, in addition to SDS-saturated UBI, at least six groups of complexes of UBI with SDS, within which four groups were populated with complexes of distinct stoichiometries: UBI-SDS(approximately 11), UBI-SDS(approximately 25), UBI-SDS(approximately 33), and UBI-SDS(approximately 42). CD spectroscopy and amide HDX of the UBI-SDS(n) complexes suggested that many of the UBI-SDS(n) complexes (n > 11) have greater alpha-helical content than native UBI. Capillary electrophoresis provides a level of detail about interactions of proteins and SDS that has not previously been accessible, and CE is an analytical and biophysical method for studies of interactions of proteins and surfactants that is both convenient and practical. This study sheds light on the formation of the enigmatic protein-SDS complexes formed during SDS polyacrylamide gel electrophoresis and brings a new tool to the study of proteins and detergents.

We report work on the fabrication of smart materials with two unique strategies: (1) self- assembly and (2) laser stereolithography. Both methods are akin to the processes used by biological systems. The first one is ideal for pattern development and the fabrication of miniaturized units in the submicron range and the second one in the 10 micrometer to 1 mm size range. By using these miniaturized units as building blocks, one can also produce smart material systems that can be used at larger length scales such as smart structural components. We have chosen to focus on two novel piezoceramic systems: (1) high-displacement piezoelectric actuators, and (2) piezoceramic hydrophone composites possessing negative Poisson ratio matrices. High-displacement actuators are essential in such applications as linear motors, pumps, switches, loud speakers, variable-focus mirrors, and laser deflectors. Arrays of such units can potentially be used for active vibration control of helicopter rotors as well as the fabrication of adaptive rotors. In the case of piezoceramic hydrophone composites, we utilize matrices having a negative Poisson's ratio in order to produce highly sensitive, miniaturized sensors. We envision such devices having promising new application areas such as the implantation of hydrophones in small blood vessels to monitor blood pressure. Negative Poisson ratio materials have promise as robust shock absorbers, air filters, and fasteners, and hence, can be used in aircraft and land vehicles.