Controlling Frequency-Domain Hong-Ou-Mandel Interference via Electromagnetically Induced Transparency

Hong-Ou-Mandel (HOM) interference is a compelling quantum phenomenon that demonstrates the nonclassical nature of single photons. Herein, we investigate an electromagnetically induced transparency-based double-Lambda four-wave mixing system from the perspective of quantized light fields. The system can be used to realize efficient HOM interference in the frequency domain. By using the reduced density operator theory, we demonstrate that, although the double-Lambda medium does not exhibit phase-dependent properties for the closed-loop case of two incident single photons, frequency-domain HOM two-photon interference occurs. For experimentally achievable optical depth conditions, our theory indicates that this double-Lambda scheme can perform high-fidelity Hadamard gate operations on frequency-encoded single-photon qubits, and thereby generate HOM two-photon NOON states with a fidelity greater than 0.99. Furthermore, we demonstrate that this scheme can be used to realize arbitrary single-qubit gates and two-qubit SWAP gates by simply controlling the laser detuning and phase, exhibiting its multifunctional properties and providing a new route to scalable optical quantum computing.Comment: 10 pages, 5 figure

Stable Isotope-Labeled Lipidomics to Unravel the Heterogeneous Development Lipotoxicity

Non-alcoholic fatty liver disease (NAFLD) as a global health problem has clinical manifestations ranging from simple non-alcoholic fatty liver (NAFL) to non-alcoholic steatohepatitis (NASH), cirrhosis, and cancer. The role of different types of fatty acids in driving the early progression of NAFL to NASH is not understood. Lipid overload causing lipotoxicity and inflammation has been considered as an essential pathogenic factor. To correlate the lipid profiles with cellular lipotoxicity, we utilized palmitic acid (C16:0)- and especially unprecedented palmitoleic acid (C16:1)-induced lipid overload HepG2 cell models coupled with lipidomic technology involving labeling with stable isotopes. C16:0 induced inflammation and cell death, whereas C16:1 induced significant lipid droplet accumulation. Moreover, inhibition of de novo sphingolipid synthesis by myriocin (Myr) aggravated C16:0 induced lipoapoptosis. Lipid profiles are different in C16:0 and C16:1-treated cells. Stable isotope-labeled lipidomics elucidates the roles of specific fatty acids that affect lipid metabolism and cause lipotoxicity or lipid droplet formation. It indicates that not only saturation or monounsaturation of fatty acids plays a role in hepatic lipotoxicity but also Myr inhibition exasperates lipoapoptosis through ceramide in-direct pathway. Using the techniques presented in this study, we can potentially investigate the mechanism of lipid metabolism and the heterogeneous development of NAFLD

A Citizen-Contributed GIS Approach for Evaluating the Impacts of Land Use on Hurricane-Harvey-Induced Flooding in Houston Area

Hurricane Harvey (2017) caused widespread flash flooding by extremely heavy rainfall and resulted in tremendous damage, including 82 fatalities and huge economic loss in the Houston, Texas area. To reduce hazards, loss, and to improve urban resilience, it is important to understand the factors that influence the occurrence of flooding events. People rely on natural resources and different land uses to reduce the severity of flood impacts and mitigate the risk. In this study, we focused the impacts of land use on Hurricane-Harvey-induced flooding inside and outside the Houston city center. With the recent trend that more citizen scientists serve in delivering information about natural disaster response, local residents in Houston areas participated in delineating the flooded areas in Hurricane Harvey. The flooding information used here generated a published map with citizen-contributed flooding data. A regional model framework with spatial autocovariates was employed to understand those interactions. Different land use patterns and types affected the potential of flooding events differently inside and outside Houston’s city center. Explicitly, we found agricultural and open space were associated with high risk of flooding outside the city center, industrial lands increased the high risk of flooding in city center, and residential areas reduced the potential of flooding both inside and outside the city center. The results can assist with future land use strategy in Houston and other areas, and mitigate potential flash flooding. This study also highlighted the contribution of citizen science to responses to natural hazards

Process Integration and Interconnection Design of Passive-Matrix LED Micro-Displays With 256 Pixel-Per-Inch Resolution

A 0.28-inch InGaN-based blue micro-LED display with 256 pixel-per-inch resolution and a pitch of 100 μm was successfully fabricated in this study. A thick Ti/Al/Ti/Au interconnection metal was deposited on the n-type gallium nitride (n-GaN) region to reduce the interconnection resistance. The micro-LED array with interconnection metal exhibits better electrical property consistency as compared with that of the traditional one. The output power, forward voltage, and external quantum efficiency of micro-LED, which measured under 1-mA current injection with the full lighting mode, are 0.8 mW, 3.0 V, and 10%, respectively. This technique has the potential to integrate InGaN-based LEDs with quantum dots for full-color applications

A siRNA targets and inhibits a broad range of SARS‐CoV‐2 infections including Delta variant

Abstract The emergence of severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) variants has altered the trajectory of the COVID‐19 pandemic and raised some uncertainty on the long‐term efficiency of vaccine strategy. The development of new therapeutics against a wide range of SARS‐CoV‐2 variants is imperative. We, here, have designed an inhalable siRNA, C6G25S, which covers 99.8% of current SARS‐CoV‐2 variants and is capable of inhibiting dominant strains, including Alpha, Delta, Gamma, and Epsilon, at picomolar ranges of IC50 in vitro. Moreover, C6G25S could completely inhibit the production of infectious virions in lungs by prophylactic treatment, and decrease 96.2% of virions by cotreatment in K18‐hACE2‐transgenic mice, accompanied by a significant prevention of virus‐associated extensive pulmonary alveolar damage, vascular thrombi, and immune cell infiltrations. Our data suggest that C6G25S provides an alternative and effective approach to combating the COVID‐19 pandemic