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Silicon nitride (Si3N4) photonic integrated circuits are rapidly developing in recent decades. The low loss of Si3N4 attracts significant attention and facilitates a wide range of applications in integrated photonics. In this work, we demonstrate the foundry fabrication of a 300-nm-thick 8-in. wafer-scale Si3N4 platform, with a microresonator intrinsic quality factor of up to 15 × 10 6 , corresponding to an ultralow loss of 2.2 dB/m. Leveraging this platform, we develop a mature process design kit, achieving a single-mode waveguide propagation loss of less than 5 dB/m, an edge coupler loss of 1.3 dB, and an insertion loss of 0.07 dB for multimode interference couplers. Utilizing the processed Si3N4 chip, we realize a hybrid integrated tunable external cavity laser with a tuning range from 1534 to 1602 nm, a record-high side-mode suppression ratio of up to 76 dB, an optical power of 26 mW, and an intrinsic linewidth of down to 314 Hz. Our work lays a solid foundation for the further development of applications, including nonlinear optics, quantum optics, optical communications, and ranging. [ABSTRACT FROM AUTHOR]

Poor blood pressure control results in tremendous morbidity and mortality in India where the leading cause of death among adults is from coronary heart disease. Despite having little formal education, community health workers (CHWs) are integral to successful public health interventions in India and other low- and middle-income countries that have a shortage of trained health professionals. Training CHWs to screen for and manage chronic hypertension, with support from trained clinicians, offers an excellent opportunity for effecting systemwide change in hypertension-related burden of disease. In this article, we describe the development of a program that trained CHWs between 2014 and 2015 in the tribal region of the Sittilingi Valley in southern India, to identify hypertensive patients in the community, refer them for diagnosis and initial management in a physician-staffed clinic, and provide them with sustained lifestyle interventions and medications over multiple visits. We found that after 2 years, the CHWs had screened 7,176 people over age 18 for hypertension, 1,184 (16.5%) of whom were screened as hypertensive. Of the 1,184 patients screened as hypertensive, 898 (75.8%) had achieved blood pressure control, defined as a systolic blood pressure less than 140 and a diastolic blood pressure less than 90 sustained over 3 consecutive visits. While all of the 24 trained CHWs reported confidence in checking blood pressure with a manual blood pressure cuff, 4 of the 24 CHWs reported occasional difficulty documenting blood pressure values because they were unable to write numbers properly. They compensated by asking other CHWs or members of their community to help with documentation. Our experience and findings suggest that a CHW blood pressure screening system linked to a central clinic can be a promising avenue for improving hypertension control rates in low- and middle-income countries.

In this study, VO2 nanoparticles were synthesized in a single step using a simple and rapid low-temperature combustion synthesis method. When used as the cathode electrode material for aqueous zinc-ion batteries. It exhibited excellent rate performance, with maximum capacities of 415 mAh g−1, 375 mAh g−1, and 350 mAh g−1 at current densities of 0.5 A g−1, 1 A g−1, and 2 A g−1, respectively. However, the cyclic performance was subpar. This study was conducted to investigate the capacity degradation, revealing the formation of plate-like Zn3V2O7(OH)2·2H2O (BZS) precipitates on the electrode surface during the cycling process. The H+ ions generated from the BZS precipitation co-intercalated with Zn2+ ions into the VO2 structure, thereby enhancing the battery specific capacity. Nevertheless, excessive H+ ions altered the electrolyte pH, resulting in vanadium dissolution and capacity degradation. Furthermore, the excessive buildup of BZS during the cycling process severely impacted ion transport, leading to capacity loss. [ABSTRACT FROM AUTHOR]

The construction of silicon‐stereogenic silanols via Pd‐catalyzed intermolecular C−H alkenylation with the assistance of a commercially available L‐pyroglutamic acid has been realized for the first time. Employing oxime ether as the directing group, silicon‐stereogenic silanol derivatives could be readily prepared with excellent enantioselectivities, featuring a broad substrate scope and good functional group tolerance. Moreover, parallel kinetic resolution with unsymmetric substrates further highlighted the generality of this protocol. Mechanistic studies indicate that L‐pyroglutamic acid could stabilize the Pd catalyst and provide excellent chiral induction. Preliminary computational studies unveil the origin of the enantioselectivity in the C−H bond activation step. [ABSTRACT FROM AUTHOR]

As a developing country with an agricultural economy as a pillar, Bangladesh is highly vulnerable to adverse effects of climate change, so the generation of high-resolution temperature maps is of great value for Bangladesh to achieve agricultural sustainable development. However, Bangladesh's weak economy and sparse meteorological stations make it difficult to obtain such maps. In this study, by mining internal features and links inside observed data, we developed an efficient data-driven downscaling technique to generate high spatial-resolution temperature distribution maps of Bangladesh directly from observed temperature data at 34 meteorological stations with irregular distribution. Based on these high-resolution historical temperature maps, we further explored a data-driven forecast technique to generate high-resolution temperature maps of Bangladesh for the period 2025–2035. Since the proposed techniques are very low-cost and fully mine internal links inside irregular-distributed observations, they can support relevant departments of Bangladesh to formulate policies to mitigate and adapt to climate change in a timely manner. [ABSTRACT FROM AUTHOR]

Electrochemical membranes (ECMs) and porous electrodes have gained much attention in a broad range of applications including water and wastewater treatment, energy production and storage, and carbon dioxide capture. Lab scale batch experiments (electrochemical stirred cells) are the baseline for developing ECMs and porous electrodes. We observed electrochemical dissolution of metal fasteners (alligator clips), used to hold porous conductive and non‐conductive membranes in batch electrochemical cells, despite being kept outside the electrolyte. The electrolyte migrated through the porous membranes by the action of capillary forces, forming a closed electrochemical circuit with the metal fasteners. This unexpected leaching can lead to misleading results for electrochemical experiments on porous electrodes and ECMs. In this study, we compared (1) porous membranes versus non‐porous electrodes, (2) hydrophilic versus hydrophobic membranes, and (3) conductive versus non‐conductive membranes in their ability to cause capillary wetting‐induced corrosion of metal fasteners. We proposed a simple solution for the problem: separating the metal fasteners from the porous membrane electrode with a non‐porous conductive graphite foil, which keeps the electrochemical circuit open. We have validated this solution and propose it as a standard method for experiments using porous electrodes and electrically conductive membranes. [ABSTRACT FROM AUTHOR]

AbstractLearning to read Chinese characters poses a considerable challenge for children, particularly those with dyslexia. We designed a tangible system, named Character Alive, to assist children aged 5 to 7 in mastering Chinese radicals and characters. The system employs animations and color cues to clarify the concepts of radicals and morphemes. It also incorporates physical radical cards that work in synergy with an artificial intelligence module to facilitate stroke tracing and character composition. We conducted a two-week within-group study involving 20 six-year-old children who used both our tangible system and an equivalent multitouch version to learn Chinese radicals and characters. The results showed that both systems significantly improved the children’s accuracy in character reading and composition. However, our tangible design outperformed the multitouch variant by increasing children’s learning motivation, enabling hands-on actions, and promoting a diverse range of beneficial learning strategies. We discuss the design implications for creating effective tangible systems to facilitate Chinese language acquisition among children. [ABSTRACT FROM AUTHOR]