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Optical patch antennas sandwiching dielectrics between metal layers have been used as deep subwavelength building blocks of metasurfaces for perfect absorbers and thermal emitters. However, for applications of these metasurfaces for optoelectronic devices, wiring to each electrically isolated antenna is indispensable for biasing and current flow. Here we show that geometrically engineered metallic wires interconnecting the antennas can function to synchronize the optical phases for promoting coherent resonance, not only as electrical conductors. Antennas connected with optimally folded wires are applied to intersubband infrared photodetectors with a single 4-nm-thick quantum well, and a polarization-independent external quantum efficiency as high as 61% (responsivity 3.3 A W −1 , peak wavelength 6.7 μm) at 78 K, even extending to room temperature, is demonstrated. Applications of synchronously wired antennas are not limited to photodetectors, but are expected to serve as a fundamental architecture of arrayed subwavelength resonators for optoelectronic devices such as emitters and modulators. Applications of metasurfaces for optoelectronic devices require wiring to each isolated antenna for biasing and current flow. Here, the authors report optimal wire interconnects design for controlling the optical properties and present antenna-enhanced mid-infrared photodetection incorporating a single quantum well.

Toward drastic enhancement of thermoelectric power factor, quantum confinement effect proposed by Hicks and Dresselhaus has intrigued a lot of researchers. There has been much effort to increase power factor using step-like density-of-states in two-dimensional electron gas (2DEG) system. Here, we pay attention to another effect caused by confining electrons spatially along one-dimensional direction: multiplied 2DEG effect, where multiple discrete subbands contribute to electrical conduction, resulting in high Seebeck coefficient. The power factor of multiple 2DEG in GaAs reaches the ultrahigh value of ~100 μWcm −1 K −2 at 300 K. We evaluate the enhancement rate defined as power factor of 2DEG divided by that of three-dimensional bulk. The experimental enhancement rate relative to the theoretical one of conventional 2DEG reaches anomalously high (~4) in multiple 2DEG compared with those in various conventional 2DEG systems (~1). This proposed methodology for power factor enhancement opens the next era of thermoelectric research. Thermoelectric power factor in multiple two-dimensional electron gas in GaAs is enhanced by the effect of multiple subbands. The enhancement rate is 4 times larger than that of conventional two-dimensional electron gas system.

The formation of the Ontong Java Nui super oceanic plateau (OJN), which is based on the model that the submarine Ontong Java Plateau (OJP), Manihiki Plateau (MP), and Hikurangi Plateau (HP) were once its contiguous fragments, could have been the largest globally consequential volcanic event in Earth’s history. This OJN hypothesis has been debated given the paucity of evidence, for example, the differences in crustal thickness, the compositional gap between MP and OJP basalts and the apparent older age of both plateaus relative to HP remain unresolved. Here we investigate the geochemical and 40 Ar- 39 Ar ages of dredged rocks recovered from the OJP’s eastern margin. Volcanic rocks having compositions that match the low-Ti MP basalts are reported for the first time on the OJP and new ~ 96–116 Ma and 67–68 Ma 40 Ar- 39 Ar age data bridge the temporal gap between OJP and HP. These results provide new evidence for the Ontong Java Nui hypothesis and a framework for an integrated tectonomagmatic evolution of the OJP, MP, and HP. The isotopic data imply four mantle components in the source of OJN that are also expressed in present-day Pacific hotspots sources, indicating origin from (and longevity of) the Pacific Large Low Shear-wave Velocity Province.

The size tunability and chemical versatility of nanostructures enable electron sources of high brightness and temporal coherence, both of which are important characteristics for high-resolution electron microscopy1–3. Despite intensive research efforts in the field, so far, only conventional field emitters based on a bulk tungsten (W) needle have been able to yield atomic-resolution images. The absence of viable alternatives is in part caused by insufficient fabrication precision for nanostructured sources, which require an alignment precision of subdegree angular deviation of a nanometre-sized emission area with the macroscopic emitter axis4. To overcome this challenge, in this work we micro-engineered a LaB6 nanowire-based electron source that emitted a highly collimated electron beam with good lateral and angular alignment. We integrated a passive collimator structure into the support needle tip for the LaB6 nanowire emitter. The collimator formed an axially symmetric electric field around the emission tip of the nanowire. Furthermore, by means of micromanipulation, the support needle tip was bent to align the emitted electron beam with the emitter axis. After installation in an aberration-corrected transmission electron microscope, we characterized the performance of the electron source in a vacuum of 10−8 Pa and achieved atomic resolution in both broad-beam and probe-forming modes at 60 kV beam energy. The natural, unmonochromated 0.20 eV electron energy loss spectroscopy resolution, 20% probe-forming efficiency and 0.4% probe current peak-to-peak noise ratio paired with modest vacuum requirements make the LaB6 nanowire-based electron source an attractive alternative to the standard W-based sources for low-cost electron beam instruments.So far, only conventional field emitters based on a bulk W needle have achieved atomic resolution in electron microscopy. Here, through the integration of a passive collimator structure and micromanipulation-based alignment of the support needle, a LaB6 nanowire emitter yields stable emission under moderate vacuum conditions and allows for atomic-resolution images and high energy resolution.

Ceramic restorations with resin-based adhesive systems have been the focus of recent attention in clinical dentistry. Yttrium-oxide-partially-stabilized zirconia (YPSZ) ceramics have optimized physical properties and exhibit favorable fracture toughness, though their bonding properties are problematic. Although functional phosphate monomers and silica-coating by tribochemical modification were expected to improve the bonding properties between YPSZ ceramics and resin-based adhesives, these two methods remain controversial. This study evaluated the efficiency of silica-coating by tribochemical modification of YPSZ ceramics. The application of phosphate monomer and a silane coupling agent on silica-coated YPSZ was also investigated. The silica-coating of YPSZ ceramics by tribochemical modification was not efficient, given the higher mechanical toughness of the densely sintered ceramics. Stable shear bond strength was achieved on silica-coated YPSZ ceramics with the cooperative interaction of phosphate monomer and silane coupling.

Objective: To test the hypothesis that dynamic load at baseline can predict radiographic disease progression in patients with medial compartment knee osteoarthritis (OA). Methods: During 1991–93 baseline data were collected by assessment of pain, radiography, and gait analysis in 106 patients referred to hospital with medial compartment knee OA. At the six year follow up, 74 patients were again examined to assess radiographic changes. Radiographic disease progression was defined as more than one grade narrowing of minimum joint space of the medial compartment. Results: In the 32 patients showing disease progression, pain was more severe and adduction moment was higher at baseline than in those without disease progression (n=42). Joint space narrowing of the medial compartment during the six year period correlated significantly with the adduction moment at entry. Adduction moment correlated significantly with mechanical axis (varus alignment) and negatively with joint space width and pain score. Logistic regression analysis showed that the risk of progression of knee OA increased 6.46 times with a 1% increase in adduction moment. Conclusions: The results suggest that the baseline adduction moment of the knee, which reflects the dynamic load on the medial compartment, can predict radiographic OA progression at the six year follow up in patients with medial compartment knee OA.

The causes of soil alkalinization in the Songnen Plain of Northeast China were mainly analyzed from two aspects, natural and anthropogenic. Natural factors of alkalinization are parent materials, topographic positions, freeze-thaw action, wind conveyance, water properties and semi-arid/sub-humid climate. Some of them were always being neglected, such as freeze-thaw action and wind conveyance. Anthropogenic causes are mainly population pressure, overgrazing and improper agricultural and economic policies. In recent decades, overgrazing played a main role in secondary soil alkalinization, which led to the decline of Leymus chinensis grasslands. Now, the alkalinization is very severe, and more than 3.2 × 10 6  ha area has been affected by salt, which becomes one of the three largest sodic–saline areas in the world.

The coronavirus disease (COVID-19) pandemic has led to a dramatic increase in facemask use. Consequently, it has been reported that exhaled airflow toward the eyes can cause the dispersal of bacteria into the eyes, potentially increasing the incidence of postoperative endophthalmitis. In addition to wearing a facemask, gaps between the surgical drape and skin can also direct exhaled airflow toward the eyes. Here, we aimed to examine how the risk of contamination varies depending on the state of the drapes. We used a carbon dioxide imaging camera to visualize changes in exhaled airflow under different drape conditions and a particle counter to evaluate changes in the number of particles around the eye. The results revealed airflow present around the eye and a significant increase in the number of particles when the nasal side of the drape was detached from the skin. However, when a metal rod called “rihika” was used to create space above the body, the airflow and number of particles were significantly reduced. Thus, if drape coverage becomes incomplete during surgery, exhaled airflow toward the eye may contaminate the surgical field. On hanging up the drape, airflow can escape in the direction of the body, potentially preventing contamination.

SummaryWe assessed the health state utility value (HSUV) reductions associated with vertebral fractures using data collected in the Japanese Osteoporosis Intervention Trial-03 (JOINT-03). Our analysis revealed that assessment of HSUVs after morphometric vertebral fracture is important to capture the burden of vertebral fractures.IntroductionEvaluation of the HSUV after fracture is important to calculate the quality-adjusted life years (QALYs) of osteoporosis patients, which is essential information in the context of health economic evaluation.MethodsJOINT-03 study patients were aged ≥65 years and treated with risedronate and vitamin K2 or risedronate alone. Radiographic information and patient-reported outcomes measured by EQ-5D and a visual analogue scale (VAS) were assessed at registration and followed up after 6, 12, and 24 months. According to differences among the dates of these assessments and the radiographic information, we classified the follow-up HSUVs calculated based on EQ-5D results into before or after fracture categories regardless of clinical symptoms.ResultsAmong 2922 follow-up HSUVs, 201 HSUVs were categorized as HSUVs that were observed after incident vertebral fractures on X-ray films. The median time from the detection of an incident vertebral fracture until the EQ-5D assessment was 53 days (25th percentile, 0 day; 75th percentile, 357 days). The impact of incident vertebral fractures on HSUVs was quantified as −0.03. Among the five health profile domains on the EQ-5D, an incident vertebral fracture had significant effects on anxiety/depression, self-care, and usual activities.ConclusionsThe results suggest that incident morphometric vertebral fracture was associated with impairment of the HSUV for patients with osteoporosis not only immediately but also several months after the fracture.

As one kind of natural refrigerant, CO2 has garnered significant in recent decades owing to its excellent thermodynamic properties and environmental friendliness. It has been considered the most competitive and potential green refrigerant compared to other natural refrigerants. On the other hand, Absorption technologies show great potential in utilizing renewable energy and waste heat. Therefore, trans-critical CO2 absorption refrigeration is considered an attractive type of refrigeration solution and has been the subject of extensive research. In this study, the model of a single-effect trans-critical CO2/ionic liquid (IL) absorption refrigeration system (TsCO2-ARS) including one internal heat exchanger was established for the simulation in this study. Novel CO2-ionic liquid (IL) mixtures were selected as working pairs for the system to investigate the simulation and obtain its optimal operating conditions. Based on vapor-liquid equilibrium experiment data of CO2/ILs and Peng-Robinson equation of state (PR-EoS), circulation ratios of the system under different working conditions were calculated. The optimal circulation ratio was determined and under its working setting, the coefficient of performance, COP of single effect TsCO2-ARS was compared with the standard operation conditions. The results of this study can provide valuable insights for the design and optimization of CO2/IL mixture utilization trans-critical CO2 absorption refrigeration systems with the internal heat exchanger.