Angle-selective perfect absorption with two-dimensional materials

Two-dimensional (2D) materials have great potential in photonic and optoelectronic devices. However, the relatively weak light absorption in 2D materials hinders their application in practical devices. Here, we propose a general approach to achieve angle-selective perfect light absorption in 2D materials. As a demonstration of the concept, we experimentally show giant light absorption by placing large-area single-layer graphene on a structure consisting of a chalcogenide layer atop a mirror and achieving a total absorption of 77.6% in the mid-infrared wavelength range (~13 μm), where the graphene contributes a record-high 47.2% absorptivity of mid-infrared light. Construction of such an angle-selective thin optical element is important for solar and thermal energy harvesting, photo-detection and sensing applications. Our study points to a new opportunity to combine 2D materials with photonic structures to enable novel device applications

Efficacy and safety of postoperative levothyroxine sodium tablets for improving serum thyroid hormone levels and tumor marker levels in patients with thyroid tumors

Levothyroxine tablet has been used for improving serum thyroid hormones. Despite its efficacy, there has been a persistent recurrence. We aimed to evaluate the efficacy of levothyroxine regimen (administered as sodium tablets or liquid) therapy, including the regime in combination with other thyroxine hormones, to determine its effectiveness and safety regarding thyroid tumor patient outcomes. An electronic search of the online databases (PubMed, EMBASE, and Web of Science) was performed in duplicate independently by two authors (SSK and LPY) to identify any potential studies published in the English language from January 2002 to October 2022. The records were retrieved using keywords and MeSH terms. The Cochrane risk of bias tool in the Review Manager (RevMan software version 5.4.) was used to evaluate the risk of bias in the included studies.  A total of 18 quality studies were reported on levothyroxine tablets. Results showed that liquid levothyroxine was more efficient than tablet levothyroxine. Further results showed that levothyroxine in combination with L-T3 or I-131 was more effective than L-T4 tablet monotherapy for improving thyroid cancer hormones. Levothyroxine tablet monotherapy is less efficient than liquid levothyroxine and/or levothyroxine combined therapy. This research recommends future research using larger randomized controlled studies

Significance of searching for ganglia in the terminal rectum/fistula of complex anorectal malformations: Related to defecation function

BackgroundThe need to search for ganglia in the terminal rectum/fistula of complex anorectal malformations (ARMs) remains controversial. This study aims to evaluate the relationship between ganglia absence in the terminal rectum/fistula and defecation function after anoplasty.MethodsA retrospective review of patients who received anoplasty for treating male imperforate anus with rectobulbar (RB)/rectoprostatic (RP) fistulas at a tertiary pediatric hospital was conducted with registered demographic data, imaging study results, and information on the terminal rectum/fistula specimen (excision extension and pathological findings). According to the pathological findings, patients were divided into Groups 1 (ganglia absence) and 2 (ganglia presence). Furthermore, the postoperative defecation function was evaluated using various rating scale questionnaires. Statistical analysis was performed using SPSS 22.0.ResultsOf the 62 patients, 18 (29.0%) showed ganglia absence in the terminal rectum/fistula. By analyzing the imaging data, spinal anomalies and spinal cord anomalies were found in 30.6% (19/62) and 56.5% (35/62) of patients, respectively. Baseline information was comparable between Groups 1 and 2 (P > 0.05). For defecation function, there were no significant differences in Kelly scores between the two groups (4.0 ± 0.8 vs. 4.4 ± 1.1, P = 0.177), while Krickenbeck (3.7 ± 1.8 vs. 5.2 ± 1.4) and Rintala (13.7 ± 3.6 vs. 16.0 ± 2.7) scores in Group 1 were significantly lower than those in Group 2 (both P < 0.05). The overall incidence of constipation was 50% (31/62), being higher for Group 1 than Group 2 (77.5% vs. 38.6%, P = 0.002). The area under the curve of ganglia absence for predicting constipation was 0.696, with 77.8% sensitivity and 61.4% specificity.ConclusionGanglia absence in the terminal rectum/fistula of male imperforate anus with RB/RP fistulas is associated with constipation after anoplasty, but it has limited predictive value for postoperative constipation. It is necessary to search for ganglia in the terminal rectum/fistula, both intraoperatively and postoperatively

Roadmap on optical energy conversion

For decades, progress in the field of optical (including solar) energy conversion was dominated by advances in the conventional concentrating optics and materials design. In recent years, however, conceptual and technological breakthroughs in the fields of nanophotonics and plasmonics combined with a better understanding of the thermodynamics of the photon energy-conversion processes reshaped the landscape of energy-conversion schemes and devices. Nanostructured devices and materials that make use of size quantization effects to manipulate photon density of states offer a way to overcome the conventional light absorption limits. Novel optical spectrum splitting and photon-recycling schemes reduce the entropy production in the optical energy-conversion platforms and boost their efficiencies. Optical design concepts are rapidly expanding into the infrared energy band, offering new approaches to harvest waste heat, to reduce the thermal emission losses, and to achieve noncontact radiative cooling of solar cells as well as of optical and electronic circuitries. Light–matter interaction enabled by nanophotonics and plasmonics underlie the performance of the third- and fourth-generation energy-conversion devices, including up- and down-conversion of photon energy, near-field radiative energy transfer, and hot electron generation and harvesting. Finally, the increased market penetration of alternative solar energy-conversion technologies amplifies the role of cost-driven and environmental considerations. This roadmap on optical energy conversion provides a snapshot of the state of the art in optical energy conversion, remaining challenges, and most promising approaches to address these challenges. Leading experts authored 19 focused short sections of the roadmap where they share their vision on a specific aspect of this burgeoning research field. The roadmap opens up with a tutorial section, which introduces major concepts and terminology. It is our hope that the roadmap will serve as an important resource for the scientific community, new generations of researchers, funding agencies, industry experts, and investors.United States. Department of Energy (DE-AC36-086038308

Changes in Fault Slip Potential Due to Water Injection in the Rongcheng Deep Geothermal Reservoir, Xiong’an New Area, North China

The Xiong’an New Area is abundant in geothermal resources due to its unique geological structure. To address whether large-scale deep geothermal exploitation will induce a fault slip, we first determined the initial in situ stress field using shallow (~4000 m) in situ stress measurements from the North China plain. After characterizing the in situ stress field, we analyzed the initial stability of the main active faults in the sedimentary strata of the Rongcheng deep geothermal reservoir based on the Mohr–Coulomb failure criteria. Assuming that this area will be subjected to forty years of continuous fluid injection, we calculated the excess pore pressure in the deep geothermal reservoir and, subsequently, estimated the fault slip potential of the main active faults in this region from 2021 to 2060. Our results indicated that both the in situ stress field in the shallow crust of the Xiong’an New Area and the Middle-Late Pleistocene active faults will initially maintain a stable state. With constant fluid injection for forty years at six geothermal wells in the Rongcheng deep geothermal reservoir, the maximum superposed excess pore pressure at a single well is 18 MPa; this excess pore pressure value impacts the stress state of faults within 8 km of the well location. These pore pressure perturbations heavily impact the F5-10, F5-11, and F9-2 segments of the Rongcheng uplift boundary fault, with FSP values of 92%, 23%, and 47% in 2060, respectively. Porosity exacts little impact on the fault slip potential on the boundary fault segments of F5-10 and F9-2 in the Rongcheng deep geothermal reservoir, while an enhanced permeability can weaken the FSP values for these faults. The predicted maximum moment magnitude of an induced earthquake due to continuous injection of forty years can be up to Mw 5.0 with a 5% fluid loss in the Rongcheng deep geothermal reservoir. Long-term water injection may increase the ambient thermoelastic stress to the point where faults in a critical (or subcritical) stress state become unstable. The results can provide a reference for geothermal development in terms of injection rate and locations of geothermal wells

Changes in Fault Slip Potential Due to Water Injection in the Rongcheng Deep Geothermal Reservoir, Xiong’an New Area, North China

The Xiong’an New Area is abundant in geothermal resources due to its unique geological structure. To address whether large-scale deep geothermal exploitation will induce a fault slip, we first determined the initial in situ stress field using shallow (~4000 m) in situ stress measurements from the North China plain. After characterizing the in situ stress field, we analyzed the initial stability of the main active faults in the sedimentary strata of the Rongcheng deep geothermal reservoir based on the Mohr–Coulomb failure criteria. Assuming that this area will be subjected to forty years of continuous fluid injection, we calculated the excess pore pressure in the deep geothermal reservoir and, subsequently, estimated the fault slip potential of the main active faults in this region from 2021 to 2060. Our results indicated that both the in situ stress field in the shallow crust of the Xiong’an New Area and the Middle-Late Pleistocene active faults will initially maintain a stable state. With constant fluid injection for forty years at six geothermal wells in the Rongcheng deep geothermal reservoir, the maximum superposed excess pore pressure at a single well is 18 MPa; this excess pore pressure value impacts the stress state of faults within 8 km of the well location. These pore pressure perturbations heavily impact the F5-10, F5-11, and F9-2 segments of the Rongcheng uplift boundary fault, with FSP values of 92%, 23%, and 47% in 2060, respectively. Porosity exacts little impact on the fault slip potential on the boundary fault segments of F5-10 and F9-2 in the Rongcheng deep geothermal reservoir, while an enhanced permeability can weaken the FSP values for these faults. The predicted maximum moment magnitude of an induced earthquake due to continuous injection of forty years can be up to Mw 5.0 with a 5% fluid loss in the Rongcheng deep geothermal reservoir. Long-term water injection may increase the ambient thermoelastic stress to the point where faults in a critical (or subcritical) stress state become unstable. The results can provide a reference for geothermal development in terms of injection rate and locations of geothermal wells