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Modern computing and communication technologies such as supercomputers and the Internet are based on optically connected networks of microwave-frequency information processors. An analogous architecture has been proposed for quantum networks, using optical photons to distribute entanglement between remote superconducting quantum processors. Here we report a step towards such a network by observing non-classical correlations between photons in an optical link and a superconducting quantum device. We generate these states of light through a spontaneous parametric down-conversion process in a chip-scale piezo-optomechanical transducer, and we measure a microwave–optical cross-correlation exceeding the Cauchy–Schwarz classical bound for thermal states. As further evidence of the non-classical character of the microwave–optical photon pairs, we observe antibunching in the microwave state conditioned on detection of an optical photon. Such a transducer can be readily connected to an independent superconducting qubit module and serve as a key building block for optical quantum networks of microwave-frequency qubits. A transducer that generates microwave–optical photon pairs is demonstrated. This could provide an interface between optical communication networks and superconducting quantum devices that operate at microwave frequencies.

Improvements in temporal resolution of single-photon detectors enable increased data rates and transmission distances for both classical and quantum optical communication systems, higher spatial resolution in laser ranging, and observation of shorter-lived fluorophores in biomedical imaging. In recent years, superconducting nanowire single-photon detectors (SNSPDs) have emerged as the most efficient time-resolving single-photon-counting detectors available in the near-infrared, but understanding of the fundamental limits of timing resolution in these devices has been limited due to a lack of investigations into the timescales involved in the detection process. We introduce an experimental technique to probe the detection latency in SNSPDs and show that the key to achieving low timing jitter is the use of materials with low latency. By using a specialized niobium nitride SNSPD we demonstrate that the system temporal resolution can be as good as 2.6 ± 0.2 ps for visible wavelengths and 4.3 ± 0.2 ps at 1,550 nm.Knowledge about detection latency provides a guideline to reduce the timing jitter of niobium nitride superconducting nanowire single-photon detectors. A timing jitter of 2.6 ps at visible wavelength and 4.3 ps at 1,550 nm is achieved.

Optical quantum memories are essential elements in quantum networks for long-distance distribution of quantum entanglement. Scalable development of quantum network nodes requires on-chip qubit storage functionality with control of the readout time. We demonstrate a high-fidelity nanophotonic quantum memory based on a mesoscopic neodymium ensemble coupled to a photonic crystal cavity. The nanocavity enables >95% spin polarization for efficient initialization of the atomic frequency comb memory and time bin–selective readout through an enhanced optical Stark shift of the comb frequencies. Our solid-state memory is integrable with other chip-scale photon source and detector devices for multiplexed quantum and classical information processing at the network nodes.

Introduction Although weight gain has been reported with the use of integrase strand transfer inhibitors (InSTI), concurrent use of tenofovir alafenamide (TAF) has been implicated in recent studies. This study examined weight changes in people living with HIV (PLWH) who switched from tenofovir disoproxil fumarate (TDF) to TAF, to clarify the relative contribution to weight gain of core agents versus TDF to TAF switch. Methods Antiretroviral‐experienced, virologically suppressed PLWH in the U.S. OPERA cohort were included if they switched from TDF to TAF (5NOV2015‐28FEB2019) and either maintained all other antiretrovirals or switched from a non‐InSTI to an InSTI. Linear mixed models were used to assess weight changes before/after the switch to TAF (restricted cubic splines on time) and rates of change over time (linear splines on time, based on the shape of the weight change curves). Changes in weight on TDF or TAF were assessed among those who maintained other antiretrovirals (overall, by core class), and those who maintained an InSTI or switched to an InSTI (by core agent). All models were adjusted for age, sex, race, (age‐sex, race‐sex interactions), BMI, CD4 cell count, endocrine disorders and concurrent medications that could affect weight. Results A total of 6908 PLWH were included, with 5479 maintaining all other antiretrovirals (boosted protease inhibitor: 746, non‐nucleoside reverse transcriptase inhibitor: 1452, InSTI: 3281) and 1429 switching from a non‐InSTI to an InSTI (elvitegravir/cobicistat: 1120, dolutegravir: 174, bictegravir: 129). In adjusted models, modest weight gain was observed over time on TDF for most (0.24 to 0.71 kg/year); raltegravir was the exception with weight loss. Switching to TAF was associated with early, pronounced weight gain for all (1.80 to 4.47 kg/year). This effect with TAF switch was observed both in PLWH maintaining other antiretrovirals and those switching to an InSTI, regardless of which InSTI agent was used. Weight gain tended to slow down or plateau approximately nine months after switch to TAF. Conclusions In this large, diverse U.S. cohort of PLWH, switching from TDF to TAF was associated with pronounced weight gain immediately after switch, regardless of the core class or core agent, suggesting an independent effect of TAF on weight gain.

We present the optical characterization of two-scale hierarchical phased-array antenna kinetic inductance detectors (KIDs) for millimeter/submillimeter wavelengths. Our KIDs have a lumped-element architecture with parallel plate capacitors and aluminum inductors. The incoming light is received with a hierarchical phased array of slot dipole antennas, split into 4 frequency bands (between 125 GHz and 365 GHz) with on-chip lumped-element band-pass filters, and routed to different KIDs using microstriplines. Individual pixels detect light for the 3 higher-frequency bands (190–365 GHz), and the signals from four individual pixels are coherently summed to create a larger pixel detecting light for the lowest frequency band (125–175 GHz). The spectral response of the band-pass filters was measured using Fourier transform spectroscopy (FTS), the far-field beam pattern of the phased-array antennas was obtained using an infrared source mounted on a 2-axis translating stage, and the optical efficiency of the KIDs was characterized by observing loads at 294 K and 77 K. We report on the results of these three measurements.

Abstract Background Increases in lipids have been observed in people with HIV (PWH) switching from tenofovir disoproxil fumarate (TDF) to tenofovir alafenamide (TAF). We assessed changes in low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG) following a switch from TDF to TAF. Methods Adults with ≥1 lipid measure before and after switch from TDF to TAF were identified in the OPERA cohort. Multivariable linear regression using generalized estimating equations was used to estimate predicted changes in lipids over time on TAF, modeled flexibly with linear splines. Results A total of 6451 PWH switched from TDF to TAF, of whom 4328 maintained all other agents. LDL-C increased significantly by 1.40 mg/dL/mo over the first 3 months on TAF, by 0.33 mg/dL/mo between 3 and 9 months and then plateauing beyond 9 months. TG increased significantly by 3.52 mg/dL/mo over the first 3 months of TAF, by 0.91 mg/mL/mo between 3 and 9 months and by 0.72 mg/mL/mo between 9 and 16 months, but decreased thereafter. Similar patterns were observed in analyses restricted to PWH who switched from TDF to TAF but maintained all other agents. Conclusions TDF-to-TAF switch was associated with LDL-C and TG increases over the first 9 to 16 months on TAF. The dynamic patterns observed cannot be attributed to changes in other agents.

We present a multi-chroic kinetic inductance detector (KID) pixel design integrated with a broadband hierarchical phased-array antenna. Each low-frequency pixel consists of four high-frequency pixels. Four passbands are designed from 125 to 365 GHz according to the atmospheric windows. The lumped element KIDs consist of 100-nm thick AlMn inductors and Nb parallel plate capacitors with hydrogenated amorphous Si dielectric. Two different coupling structures are designed to couple millimeter-wave from microstrip lines to KIDs. The KID designs are optimized for a 10-m-class telescope at a high, dry site, for example, the Leighton Chajnantor Telescope. Preliminary measurement results using Al KIDs are discussed.

Background and Objective Many people living with HIV (PLWH) on stable tenofovir disoproxil fumarate (TDF)-containing regimens have switched to tenofovir alafenamide (TAF), despite the potential lipid-lowering effect of TDF. We aimed to assess the impact of switching from TDF to TAF on lipids in real-world clinical practice. Methods PLWH prescribed TDF for ≥ 4 weeks who switched to TAF were identified in the OPERA cohort. Patterns of dyslipidemia were compared before and after switch based on NCEP ATPIII guidelines. Elevated 10-year risk of atherosclerotic cardiovascular disease (ASCVD ≥ 7.5%) and statin use were assessed. Results Among 6423 PLWH switched from TDF to TAF, the proportion with dyslipidemia/severe dyslipidemia observed after switch from TDF to TAF increased statistically significantly ( p < 0.0001) with total cholesterol (5–10%), low-density lipoprotein cholesterol (16–23%), and triglycerides (21–27%), but decreased statistically significantly with high-density lipoprotein cholesterol (35–30%, p < 0.0001). These patterns of dyslipidemia persisted in sensitivity analyses restricted to PLWH who maintained all other antiretrovirals ( N = 4328) or stratified by pharmaco-enhancer use before and after switch. An elevated ASCVD risk was detected in 29% before and 31% after switch. As many as 59% of PLWH with an elevated ASCVD risk were not prescribed a statin after switch from TDF to TAF. Conclusions In this large, diverse population of PLWH in the USA, the switch from TDF to TAF was associated with development of less favorable lipid profiles, regardless of pharmaco-enhancers or third-agent use. Statins remained underutilized after a switch from TDF to TAF.

Background People living with HIV (PLWH) have been observed to have twice the risk for atherosclerotic cardiovascular disease (ASCVD) as the general population. Increases in total and low-density lipoprotein cholesterol have been observed in PLWH switching from tenofovir disoproxil fumarate (TDF) to tenofovir alafenamide (TAF). Changes in regimens represent an opportunity for healthcare providers to assess health markers and address clinical concerns. Current guidelines recommend initiating statin therapy in individuals with an elevated ASCVD risk. Failure to initiate statins in PLWH with an ASCVD ≥ 7.5% at switch represents a missed opportunity for statin initiation. We aimed to assess missed opportunities for statin therapy in PLWH switching from TDF to TAF-containing antiretroviral therapy. Methods Adults switching from TDF to TAF with ≥1 lipid measure on TDF ≤6 months prior to switch and ≥1 lipid measure ≥7 days after switch to TAF were identified in the OPERA® cohort (84 clinics in 18 US states/territories). The proportion of PLWH prescribed statins pre- and post-switch was stratified by ASCVD risk (recommended threshold: ASCVD ≥ 7.5%). The ASCVD score was imputed using the limit value for components out of the pre-specified range. Results 6,451 PLWH switched from TDF to TAF (Figure 1); over 90% had ASCVD scores available pre- (n = 5801) and post-switch (n = 5881). High ASCVD risk (≥7.5%) was more likely post-switch (34.1) than pre-switch (32.1%, P = 0.02; Figure 2). Of those with high ASCVD risk, only 31% and 41% were prescribed statins pre- vs. post-switch, respectively (Figure 3), representing a considerable missed opportunity for ASCVD prevention, with 59% of PLWH with an elevated risk of ASCVD not prescribed statins after switch from TDF to TAF. ASCVD scores were imputed for those outside the range of the score (e.g., patients < 40 years of age) to evaluate the entire population. Comparable results were obtained when the analysis was limited to PLWH who did not require ASCVD score imputation. Conclusion Despite a switch from TDF to TAF being associated with higher numbers of PLWH with elevated ASCVD risk, most did not receive a statin, representing considerable missed opportunities to reduce risk of cardiovascular disease in this at-risk population. Disclosures All authors: No reported disclosures.