Design and Fabrication of Stretchable Microwave Transmission Lines Based on a Quasi-Microstrip Structure.

Radio frequency (RF) electronics are vital components of stretchable electronics that require wireless capabilities, ranging from skin-interfaced wearable systems to implantable devices to soft robotics. One of the key challenges in stretchable electronics is achieving near-lossless transmission line technology that can carry high-frequency electrical signals between various RF components. Almost all existing stretchable interconnection strategies only demonstrate direct current or low-frequency electrical properties, limiting their use in high frequencies, especially in the MHz to GHz range. Here, we describe the design and fabrication of a simple stretchable RF transmission line strategy that integrates a quasi-microstrip structure into a stretchable serpentine microscale interconnection. We show the effects of quasi-microstrip structural dimensions on the RF performance based on detailed quantitative analysis and experimentally demonstrate the optimized device capable of carrying RF signals with frequencies of up to 40 GHz with near-lossless characteristics. To show the potential application of our transmission line in stretchable microwave electronics, we designed a single-stage power amplifier system with a gain of 9.8 dB at 9 GHz that fully utilizes our quasi-microstrip transmission line technology.

Micromolded honeycomb scaffold design to support the generation of a bilayered RPE and photoreceptor cell construct.

Age-related macular degeneration (AMD) causes blindness due to loss of retinal pigment epithelium (RPE) and photoreceptors (PRs), which comprise the two outermost layers of the retina. Given the small size of the macula and the importance of direct contact between RPE and PRs, the use of scaffolds for targeted reconstruction of the outer retina in later stage AMD and other macular dystrophies is particularly attractive. We developed microfabricated, honeycomb-patterned, biodegradable poly(glycerol sebacate) (PGS) scaffolds to deliver organized, adjacent layers of RPE and PRs to the subretinal space. Furthermore, an optimized process was developed to photocure PGS, shortening scaffold production time from days to minutes. The resulting scaffolds robustly supported the seeding of human pluripotent stem cell-derived RPE and PRs, either separately or as a dual cell-layered construct. These advanced, economical, and versatile scaffolds can accelerate retinal cell transplantation efforts and benefit patients with AMD and other retinal degenerative diseases.

Frequency-dependent and time-variant alterations of neural activity in post-stroke depression: A resting-state fMRI study.

BACKGROUND: Post-stroke depression (PSD) is one of the most frequent psychiatric disorders after stroke. However, the underlying brain mechanism of PSD remains unclarified. Using the amplitude of low-frequency fluctuation (ALFF) approach, we aimed to investigate the abnormalities of neural activity in PSD patients, and further explored the frequency and time properties of ALFF changes in PSD. METHODS: Resting-state fMRI data and clinical data were collected from 39 PSD patients (PSD), 82 S patients without depression (Stroke), and 74 age- and sex-matched healthy controls (HC). ALFF across three frequency bands (ALFF-Classic: 0.01-0.08 Hz; ALFF-Slow4: 0.027-0.073 Hz; ALFF-Slow5: 0.01-0.027 Hz) and dynamic ALFF (dALFF) were computed and compared among three groups. Ridge regression analyses and spearman's correlation analyses were further applied to explore the relationship between PSD-specific alterations and depression severity in PSD. RESULTS: We found that PSD-specific alterations of ALFF were frequency-dependent and time-variant. Specially, compared to both Stroke and HC groups, PSD exhibited increased ALFF in the contralesional dorsolateral prefrontal cortex (DLPFC) and insula in all three frequency bands. Increased ALFF in ipsilesional DLPFC were observed in both slow-4 and classic frequency bands which were positively correlated with depression scales in PSD, while increased ALFF in the bilateral hippocampus and contralesional rolandic operculum were only found in slow-5 frequency band. These PSD-specific alterations in different frequency bands could predict depression severity. Moreover, decreased dALFF in contralesional superior temporal gyrus were observed in PSD group. LIMITATIONS: Longitudinal studies are required to explore the alterations of ALFF in PSD as the disease progress. CONCLUSIONS: The frequency-dependent and time-variant properties of ALFF could reflect the PSD-specific alterations in complementary ways, which may assist to elucidate underlying neural mechanisms and be helpful for early diagnosis and interventions for the disease.

Depression circuit adaptation in post-stroke depression.

BACKGROUND: Lesion locations of post-stroke depression (PSD) mapped to a depression circuit which centered by the left dorsolateral prefrontal cortex (DLPFC). However, it remains unknown whether the compensatory adaptations that may occur in this depression circuit due to the lesions in PSD. METHODS: Rs-fMRI data were collected from 82 non-depressed stroke patients (Stroke), 39 PSD patients and 74 healthy controls (HC). We tested the existence of depression circuit, examined PSD-related alterations of DLPFC-seeded connectivity and their associations with depression severity, and analyzed the connectivity between each repetitive transcranial magnetic stimulation (rTMS) target and DLPFC to find the best treatment target for PSD. RESULTS: We found that: 1) the left DLPFC showed significantly stronger connectivity to lesions of PSD than Stroke group; 2) in comparison to both Stroke and HC groups, PSD exhibited increased connectivity with DLPFC in bilateral lingual gyrus, contralesional superior frontal gyrus, precuneus, and middle frontal gyrus (MFG); 3) the connectivity between DLPFC and the contralesional lingual gyrus positively correlated with depression severity; 4) the rTMS target in center of MFG showed largest between-group difference in connectivity with DLPFC, and also reported the highest predicted clinical efficacy. LIMITATIONS: Longitudinal studies are required to explore the alterations of depression circuit in PSD as the disease progress. CONCLUSION: PSD underwent specific alterations in depression circuit, which may help to establish objective imaging markers for early diagnosis and interventions of the disease.

Demographics, Birth Parameters, and Social Determinants of Health Among Opioid-Exposed Mother-Infant Dyads Affected by Neonatal Abstinence Syndrome in Pennsylvania, 2018-2019.

OBJECTIVES: To characterize demographics, birth parameters, and social determinants of health among mother-infant dyads affected by neonatal abstinence syndrome (NAS) in Pennsylvania. METHODS: We linked 2018-2019 NAS surveillance data to birth record data using probabilistic methods and then geospatially linked to local social determinants of health data based on residential address. We generated descriptive statistics and used multivariable mixed-effects logistic regression to model the association between maternal characteristics, birth parameters, social determinants of health, and NAS. RESULTS: In adjusted models maternal age > 24, non-Hispanic white race/ethnicity, low educational attainment, Medicaid as payor at delivery, inadequate or no prenatal care, smoking during pregnancy, and low median household income were associated with NAS. We found no significant associations between NAS and county-level measures of clinician supply, number of substance use treatment facilities, or urban/rural designation. CONCLUSIONS FOR PRACTICE: This study characterizes mother-infant dyads affected by NAS using linked non-administrative, population data for Pennsylvania. Results demonstrate a social gradient in NAS and inequity in prenatal care receipt among mothers of infants with NAS. Findings may inform implementation of state-based public health interventions.

Individual and Neighborhood Characteristics Associated With Confirmatory and Follow-up Blood Lead Testing Among Children With Elevated Blood Lead Levels.

OBJECTIVES: The aim of this study was to assess the proportions and likelihood of children who receive confirmatory and follow-up blood lead testing within the recommended time frames after an initial capillary elevated blood lead level (EBLL) and confirmed EBLL, respectively, by individual and neighborhood-level sociodemographic characteristics. DESIGN: We linked and used blood testing and sociodemographic characteristics data from a Pennsylvania birth cohort including children born between 2017 and 2018. Generalized linear mixed models were constructed to examine the associations between sociodemographic factors and having recommended confirmatory and follow-up testing. SETTING: A population-based, retrospective cohort study. PARTICIPANTS: In this birth cohort, children who underwent at least 1 BLL test were followed up to 24 months of age. Children with a first unconfirmed (n = 6259) and confirmed BLL (n = 4213) ≥ 5 µg/dL were included in the analysis. MAIN OUTCOME MEASURE: Children had confirmatory and follow-up testing within the recommended time frames. RESULTS: Of the children with unconfirmed and confirmed EBLLs, 3555 (56.8%) and 1298 (30.8%) received confirmatory and follow-up testing, respectively. The proportions of the 2 outcome measures were lower among children experiencing certain sociodemographic disadvantages. In the univariate analyses, lower initial BLLs, older age, non-Hispanic Blacks, lower maternal educational levels, maternal Medicaid, The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) enrollment, maternal smoking, and higher quartiles of neighborhood poverty and old housing were associated with lower odds of having confirmatory and follow-up testing. However, in multivariate models, children with lower initial BLLs, older age, maternal smoking, and non-Hispanic Blacks were significantly less likely to have confirmatory and follow-up testing. CONCLUSIONS: There were deficiencies in having recommended confirmatory and follow-up blood lead testing among children, especially those with sociodemographic disadvantages. Public health agencies and stakeholders should finetune policies to improve follow-up testing in conjunction with primary and secondary preventions for early detection and reduction of lead exposure among targeted children at risk of lead poisoning.

Adolescent Sexting, Violence, and Sexual Behaviors: An Analysis of 2014 and 2016 Pennsylvania Youth Risk Behavior Survey Data.

BACKGROUND: Sexting is common among adolescents and is associated with numerous health risk behaviors and negative psychosocial constructs. This study examined the relationships between high school students' experiences with sexual violence victimization, dating violence victimization, and engagement in risky sexual behaviors with experiences of receiving sexts. METHODS: Cross-sectional data from the 2014 to 2016 data from Pennsylvania Youth Risk Behavior. Participants were selected using an independent 2-stage cluster sample design to produce a statewide population-based sample. The pencil and paper surveys were conducted in school. Participants included 6734 Pennsylvania high school students in grades 9-12. RESULTS: Overall, 29.0% of Pennsylvania high school students had received a sext, which varied by sex, race/ethnicity, school grade, and sexual identity. Students who engaged in sexual risk behaviors, experienced dating violence, or experienced lifetime sexual violence outside of the dating context had a significantly higher prevalence of receiving a sext than students who did not engage in those behaviors or have those experiences. CONCLUSIONS: Early screening and prevention efforts that include discussions about sexting behaviors may help prevent other negative outcomes, such as risky sexual behaviors and interpersonal violence. Addressing sexting in the education and health sectors may help to prevent other related harmful health and violence experiences during adolescence.

Blood Lead Level Testing and Retesting Among Newly Arriving Refugee Children, Pennsylvania, 2015-2019.

Objectives. To (1) determine the prevalence of elevated blood lead levels (EBLLs; ≥ 5 µg/dL) among newly arrived refugee children, (2) understand the demographic characteristics of refugee children with EBLLs, and (3) assess health care providers' compliance with Centers for Disease Control and Prevention (CDC) recommendations for retesting. Methods. We matched refugee demographic data (2015-2019) from the CDC's Electronic Disease Notification (EDN) system with lead-testing laboratory report data from the Pennsylvania National Electronic Disease Surveillance System using Match*Pro software. Results. Of 3833 refugee children 16 years or younger in the EDN system, matching identified 3142 children with blood lead level data. Among children with blood lead level data, 578 (18.4%) had EBLLs. Among children with EBLLs, 341 (59.0%) were male. Of the 1370 children aged 6 years or younger with blood level test results, 335 (24.5%) had initial EBLLs, and only 78 (5.7%) were retested within 3 to 6 months. Of the 335 children 6 years or younger with an initial EBLL, only 44 (13.1%) were retested within 3 to 6 months. Conclusions. Following up on refugee children with EBLLs is necessary to ensure that they do not have continued lead exposure. (Am J Public Health. 2022;112(S7):S706-S714. https://doi.org/10.2105/AJPH.2022.306856).

Effect of HCV or HIV infection on mortality among hospitalized persons who used opioids, 2000-2010.

Mortality due to opioid misuse and overdose has increased substantially in the United States over the past two decades. The study objective was to describe the causes of death among persons with opioid-related hospitalizations and examine survival by Hepatitis C virus (HCV) or HIV. Opioid-related hospitalization records in Pennsylvania from 2000 to 2010 were linked to death registry files to assess cause of death, and survival from first hospital discharge date to death date, or December 31, 2010. Accelerated failure time models were used to compare survival between persons with and without HCV or HIV diagnoses. Among the 136,416 individuals with an opioid-related hospitalization, 13.0% died over a median of 56 months of follow-up; the most common causes of death were circulatory diseases (26.4%) and drug overdose (23.5%). There were 27,122 (19.9%) and 3662 (2.7%) persons who had an HCV and HIV diagnosis, respectively. Among patients aged ≥20 years, those with HCV had shorter survival time compared to those without HCV, with discrepancies more pronounced at older ages. Patients with HIV also had shorter survival time (time ratio: 0.29 [95% CI: 0.26, 0.34]) compared to without HIV. These findings show that in a cohort of patients with opioid-related hospitalizations, those with HCV or HIV diagnoses have shorter survival. This has public health implications, providing further evidence that medical providers should educate patients who use opioids about the risks of HCV and HIV infection and focus prevention and treatment to decrease mortality among patients hospitalized for opioid use.

Battery-free, tuning circuit-inspired wireless sensor systems for detection of multiple biomarkers in bodily fluids.

Tracking the concentration of biomarkers in biofluids can provide crucial information about health status. However, the complexity and nonideal form factors of conventional digital wireless schemes impose challenges in realizing biointegrated, lightweight, and miniaturized sensors. Inspired by the working principle of tuning circuits in radio frequency electronics, this study reports a class of battery-free wireless biochemical sensors: In a resonance circuit, the coupling between a sensing interface and an inductor-capacitor oscillator through a pair of varactor diodes converts a change in electric potential into a modulation in capacitance, resulting in a quantifiable shift of the resonance circuit. Proper design of sensing interfaces with biorecognition elements enables the detection of various biomarkers, including ions, neurotransmitters, and metabolites. Demonstrations of "smart accessories" and miniaturized probes suggest the broad utility of this circuit model. The design concepts and sensing strategies provide a realistic pathway to building biointegrated electronics for wireless biochemical sensing.

Trench field-effect transistors integrated in a microfluidic channel and design considerations for charge detection.

Field-effect transistors (FETs) combined with a microfluidic system allow for the electrical detection of charged materials moving in a microfluidic channel. Here, we demonstrate trench-shaped silicon FETs with the combination of a microfluidic channel that can be used for simultaneous electrical and optical detection of charged fluorescent beads. The n-channel silicon trench FETs have a maximum transconductance of 1.83 × 10-5 S at near-zero gate bias voltage, which is beneficial for the high sensitivity of electrical detection. The optical transparency and physical robustness of the integrated microfluidic channel are achieved by a polydimethylsiloxane (PDMS)/glass hybrid cover combining the good sealing characteristics of PDMS, and the thin and flat properties of glass. Device evaluation methodologies and measurement approaches are also presented demonstrating a synchronized time-lapse imaging and electronic detection of bead transport. The proposed device and design consideration could advance the promise of electronic sensing to measure potential differences induced by charged analytes.

Preparation and properties of SiC/SiOX heterojunction fiber reinforced porous SiC composite materials.

Porous silicon carbide composite ceramics were prepared by partial sintering method and sacrificial silicon, with phenolic resin applied as carbon template, and silicon powder as silicon source and pore-forming agent. It showed a composite structure of SiC/SiO2/SiC sandwich shell structure and SiC/SiOX heterojunction nanofiber. Through an investigation into the effect of carbon-silicon atomic ratio on the structure and thermodynamic properties of porous SiC. It was revealed that the carbon network formed by the phenolic resin played a role in restricting the position of the silicon powder and building a regularly-arranged porous SiC structure. The prepared samples reached a porosity of 50-75% while exhibiting a low thermal conductivity ranging from 0.74 to 1.3 W/(m·K), which is attributed to the nanoscale phonon dispersion mechanism and nanofiber thermal insulation, together with high stiffness. Porous ceramics demonstrate both mechanical and thermal insulation properties, which makes them applicable as thermal protection materials for hypersonic aircraft. This is effectively in reducing the aerodynamic thermal effects of hypersonic aircraft.

Ultrafast Silicon Nanomembrane Microbolometer for Long-Wavelength Infrared Light Detection.

The microbolometer is the cornerstone device for imaging in the long-wavelength infrared range (LWIR) at room temperature. The state-of-the-art commercial microbolometers usually have a large thermal time constant (TTC) of over 10 ms, limited by their substantial device heat capacity. Moreover, the minimal pixel size of state-of-the-art bolometer is around 10 µm by 10 µm to ensure sufficient power absorption per pixel. Here, we demonstrate an ultrafast silicon nanomembrane microbolometer with a small heat capacity of around 1.9 × 10-11J/K, which allows for its operation at a speed of over 10 kHz, corresponding to a TTC of less than 16 µs. Moreover, a compact diabolo antenna is leveraged for efficient LWIR light absorption, enabling the downscaling of the active area size to 6.2 µm by 6.2 µm. Because of the complementary metal oxide semiconductor (CMOS)-compatible fabrication processes, our demonstration here may lead to a future high-resolution and high-speed LWIR imaging solution.

S- to X-Band Stretchable Inductors and Filters for Gigahertz Soft and Epidermal Electronics.

To fulfill the increasing demand for radiofrequency (RF) wireless communication capacity for epidermal electronics, stretchable integrated circuits (ICs) in the gigahertz (GHz) range are desirable. Lumped RF inductors, as a key component in RFICs, typically dominate a large portion of the circuit/chip area and therefore make such inductors mechanically stretchable is critical for GHz-frequency stretchable RFICs. Most of the reported stretchable inductors operate in the MHz frequency range. The only GHz stretchable inductor shows a quality factor of about 2, limiting its potential RF applications. Here, stretchable inductors with a high quality factor of Q > 12.6 and resonance operation frequency of fres > 11.6 GHz are demonstrated by combining microspirals with stretchable structures, overcoming all of the shortcomings of previous demonstrations. Furthermore, a stretchable 1.5-2.6 GHz filter with a peak insertion loss of -2.3 dB at 1.8 GHz is developed, showing negligible performance changes under stretching or on the skin to demonstrate the utility in practical wireless applications like GSM and Bluetooth (2.45 GHz) bands. The demonstrations can facilitate multiple GHz epidermal RFICs in the future.

Effects of Individual and Neighborhood Characteristics on Childhood Blood Lead Testing and Elevated Blood Lead Levels, A Pennsylvania Birth Cohort Analysis.

BACKGROUND: Despite declining lead exposure among U.S. children, childhood blood lead level (BLL) undertesting and elevation remains a public health issue. This study explores the impacts of maternal, infant, and neighborhood characteristics on the receipt of lead testing and having elevated BLLs (EBLLs) among children under age two. METHODS: Pennsylvania infants born in 2015 and 2016 were followed to 24 months. Birth certificate data were linked to 2015 through 2018 blood lead surveillance data and neighborhood data on household income, poverty, and the burden of houses built before 1970. Generalized linear mixed models were used to examine the individual and neighborhood characteristics independently and/or interactively affecting the likelihood of lead testing and of having EBLLs. RESULTS: A total of 48.6% of children were tested for BLLs, and 2.6% of them had confirmed EBLLs. The likelihood of lead testing and of having EBLLs among non-Hispanic black children was respectively 7% and 18% higher than white children. Children born to mothers with the lowest educational attainment (

Vapor condensation with daytime radiative cooling.

A radiative vapor condenser sheds heat in the form of infrared radiation and cools itself to below the ambient air temperature to produce liquid water from vapor. This effect has been known for centuries, and is exploited by some insects to survive in dry deserts. Humans have also been using radiative condensation for dew collection. However, all existing radiative vapor condensers must operate during the nighttime. Here, we develop daytime radiative condensers that continue to operate 24 h a day. These daytime radiative condensers can produce water from vapor under direct sunlight, without active consumption of energy. Combined with traditional passive cooling via convection and conduction, radiative cooling can substantially increase the performance of passive vapor condensation, which can be used for passive water extraction and purification technologies.

Ultrathin micromolded 3D scaffolds for high-density photoreceptor layer reconstruction.

Polymeric scaffolds are revolutionizing therapeutics for blinding disorders affecting the outer retina, a region anatomically and functionally defined by light-sensitive photoreceptors. Recent engineering advances have produced planar scaffolds optimized for retinal pigment epithelium monolayer delivery, which are being tested in early-stage clinical trials. We previously described a three-dimensional scaffold supporting a polarized photoreceptor monolayer, but photoreceptor somata typically occupy multiple densely packed strata to maximize light detection. Thus, patients with severe photoreceptor degeneration are expected to extract greater benefits from higher-density photoreceptor delivery. Here, we describe the microfabrication of a biodegradable scaffold patterned for high-density photoreceptor replacement. The "ice cube tray" structure optimizes mechanical properties and cell-to-biomaterial load, enabling production of a multicellular photoreceptor layer designed for outer retinal reconstruction. Our approach may also be useful in the production of a multitude of micro- and nanoscale structures for multilayered cell delivery in other tissues.

Demographic and exposure characteristics as predictors of serum per- and polyfluoroalkyl substances (PFASs) levels - A community-level biomonitoring project in Pennsylvania.

Per- and polyfluoroalkyl substances (PFASs) are widely used in industrial and consumer products and have been linked to various adverse health effects. Communities near two former military bases in Pennsylvania were exposed to PFAS through contaminated drinking water for several decades. The Pennsylvania Department of Health (DOH) conducted biomonitoring of 235 randomly selected community members living in four public water system (PWS) service areas to evaluate a toolkit developed by the Centers for Disease Control and Prevention (CDC) and the Agency for Toxic Substances and Disease Registry (ATSDR). DOH also collected data on participants' demographics, exposure history and self-reported health conditions. Serum PFAS levels were compared with the national averages for 2013-2014 and their relationships with demographic and exposure characteristics were analyzed. Of the 11 PFASs analyzed for, only perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), perfluorohexanesulfonic acid (PFHxS) and perfluorononanoic acid (PFNA) were consistently detected in the serum samples. The average levels of PFOA, PFOS, PFHxS and PFNA among the study participants were 3.13, 10.24, 6.64 and 0.74 µg per liter (µg/L), respectively. Overall, 75, 81, 94 and 59 percent of the study participants had levels exceeding the national average for PFOA (1.94 µg/L), PFOS (4.99 µg/L), PFHxS (1.35 µg/L) and PFNA (0.66 µg/L), respectively. Results indicated associations between serum levels of some PFAS compounds and sex, age, employment in the study area, PWS area, quantity of daily tap water consumption, and length of residence in the study area.

Boundary-directed epitaxy of block copolymers.

Directed self-assembly of block copolymers (BCPs) enables nanofabrication at sub-10 nm dimensions, beyond the resolution of conventional lithography. However, directing the position, orientation, and long-range lateral order of BCP domains to produce technologically-useful patterns is a challenge. Here, we present a promising approach to direct assembly using spatial boundaries between planar, low-resolution regions on a surface with different composition. Pairs of boundaries are formed at the edges of isolated stripes on a background substrate. Vertical lamellae nucleate at and are pinned by chemical contrast at each stripe/substrate boundary, align parallel to boundaries, selectively propagate from boundaries into stripe interiors (whereas horizontal lamellae form on the background), and register to wide stripes to multiply the feature density. Ordered BCP line arrays with half-pitch of 6.4 nm are demonstrated on stripes >80 nm wide. Boundary-directed epitaxy provides an attractive path towards assembling, creating, and lithographically defining materials on sub-10 nm scales.