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Identifying the phytoplankton origin of particulate organic matter (POM) in the deep ocean is challenging due to the changing phytoplankton composition and varied extent of decomposition by heterotrophic bacteria and zooplankton. Here, we report vertical distributions of amino acid stable carbon isotope values (δ13C) measured in particles in the South China Sea. Carbon‐weighted amino acid δ13C values generally parallel bulk POM δ13C profiles with a positive offset from 2.4‰ in the surface water to 6.0‰ in deep. Accordingly, a lability model is introduced to describe the relative distribution and isotopic linkage of labile and refractory particulate organic carbon. Temporal changes of amino acid δ13C were observed during the microbial decomposition of two phytoplankton strains, the prokaryote cyanobacterium Synechococcusand the eukaryote diatom Thalassiosira weissflogii. Principal component analysis of individual amino acid δ13C values from the decomposing cells separate samples into two components, reflecting the influence of microbial decomposition and taxonomic differences, respectively. These two components were further applied to particles. A major contribution from decomposing phytoplankton to particles below the euphotic zone was observed, with more prokaryote organic matter in the basin and a larger contribution from eukaryotes at stations near the productive northern shelf. Our findings show the applicability of amino acid δ13C values in tracing the lability and phytoplankton origins of POM in samples with varied extents of decomposition in marine environments.

In this letter, a dual-wideband dual-circularly polarized (CP) reflectarray (RA) with 1013 dual-CP RA cells is proposed. The overall size is 161 × 161 × 1.8 mm. Composed of a metal reflection plate and a substrate printed with circuits of fan-shaped, arc-shaped and rectangular patterns, current paths with different lengths can be formed, and multiple resonance points can be introduced to expand the working bandwidth (BW). The −10 dB cross-polarization BW of cells has reached 83.67% (16.03–39.09 GHz). Center frequencies of the right-handed (RH) CP and left-handed (LH) CP reflected beams are designed to point along (ϕ, θ) = (90°, 20°) at 19 GHz and (ϕ, θ) = (90°, −20°) at 31 GHz. Specifically, the 3 dB gain BW of RHCP and LHCP reflected beams is 43.8% (7.3–27.0 GHz) and 47.1% (24.5–39.6 GHz), respectively. 1.5 dB axial ratio (AR) BWs are greater than 90.1%. The dual-wideband and dual-CP characteristics enable the proposed RA to meet the communication requirements of satellite communication transmission and reception at the same time and become a promising candidate technology for long-distance communication for K-band and Ka-band applications.

An optically transparent right-handed (RH) circularly polarized (CP) reflectarray (RA) with 3940 cells is proposed in this communication. The overall structure is composed of a 0.125-mm-thick polyethylene terephthalate (PET) film with fine metal line (FML), quartz glass with a thickness of 0.5 mm, a 0.6-mm air layer, indium tin oxide (ITO) ground, and an RHCP feed horn. The overall size of the reflection plane is $170\times 170\times 1.225$ mm. The shaped pattern of a double arrow, two diamond, and a chain with three incomplete diamonds form the circuit of unit cell. The RA cell is miniaturized ( $2.4\times 2.4$ mm) by bending the corresponding current path with a linewidth of $40~\mu $ m. To compensate for the loss induced by the FML, we increased the resolution of the reflection plane, and the measured results showed that the peak gain and aperture efficiency (AE) reached 32.5 dBic and 54.9%, respectively. The 3-dB gain bandwidth (BW) reached 23.2% (28.5–36 GHz), and the axial ratio (AR) is less than 1.5 dB across the frequency band. These advantages, such as optical transparency, high directionality, and good circular polarization characteristics, make it a potential candidate for satellite communication applications.

IMPORTANCE: Sustained-release corticosteroids offer the potential of improved compliance and greater patient convenience for anti-inflammatory treatment after cataract surgery. However, they are substantially more expensive than postoperative corticosteroid eye drops, which have historically been standard care. OBJECTIVE: To examine the use and cost of sustained-release corticosteroids in patients with Medicare who underwent cataract surgery in the US during the temporary pass-through reimbursement program period. DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study examined Medicare fee-for-service (FFS) claims from beneficiaries with at least 12 continuous months of Medicare enrollment who underwent at least 1 cataract surgery from March 2019 through December 2021. Patients younger than 65 years, those with missing demographic information, those who had more than 1 cataract surgery on each eye, and those who received more than 1 corticosteroid on the day of surgery were excluded. Cataract surgeries with concurrent use of dexamethasone intraocular suspension 9% or dexamethasone ophthalmic insert were identified. Information on surgeon demographic characteristics and costs of surgery and drugs were extracted. Data were analyzed from June 15 to December 4, 2022. EXPOSURE: Use of dexamethasone intraocular suspension 9% or dexamethasone ophthalmic insert during cataract surgery. MAIN OUTCOME MEASURES: Utilization rate and cost of dexamethasone intraocular suspension 9% and dexamethasone ophthalmic insert among Medicare FFS beneficiaries who underwent cataract surgery. RESULTS: A total of 4 252 532 cataract surgeries in Medicare FFS beneficiaries (mean [SD] age, 74.8 [5.8] years; 1 730 811 male [40.7%] and 2 521 721 female [59.3%]) were performed by 12 284 ophthalmologists (8876 male [72.3%], 2877 female [23.4%], and 531 sex unknown [4.3%]). In all, 34 627 beneficiaries (0.8%) received dexamethasone intraocular suspension 9% and 73 430 (1.7%) received a dexamethasone ophthalmic insert; the use of both drugs increased over the study period. The mean (SD) Medicare allowed charges for dexamethasone intraocular suspension 9% and dexamethasone ophthalmic insert were $531.47 ($141.52) and $538.49 ($63.79), respectively. CONCLUSIONS AND RELEVANCE: Despite offering the potential of improved compliance and greater patient convenience, findings of this study suggest that sustained-release corticosteroid use during cataract surgery was low and associated with cost increases to the health care system vs conventional postoperative eye drops. As these new products must be priced high enough to qualify for the Medicare pass-through program, unreasonable cost may have been a deterrent to their use, suggesting that the current Medicare reimbursement rules may not be appropriate for sustained-release postoperative corticosteroids in cataract surgery.

A broadband low-profile dual-circularly polarized (dual-CP) reflect-array (RA) cells covering both K- and Ka-bands is presented in this article. As an anisotropic impedance surface, the functional layer is designed based on a multi-resonant structure and printed on a substrate with a thickness of 0.762 mm. The circuit is composed of an elliptical ring, arc-shaped and rectangular metal microstrip lines. The air layer between the functional layer and the metal plate can effectively extend the cell bandwidth (BW), and the overall profile is 1.8 mm. The dynamic phase and Berry phase can be adjusted by changing the size of the arc-shaped microstrip lines and the rotation of the cells. The diffraction results show that the phase of left-handed (LH) circularly polarized (CP) and right-handed (RH) CP waves can be controlled independently and reflected by high purity with the cross-polarization BW of 64% (19.72 $\sim $ 38.44 GHz). A dual-CP RA with 1013 cells is designed to realize reflect beams at $\theta $ = −20° for LHCP wave and $\theta $ = 15° for RHCP wave at 30 GHz. Furthermore, the 3 dB gain BW can cover the Ka-band and is expected to be used in wireless and satellite communication systems.

A compact antenna with the characteristic of wide-angle frequency beam scanning based on complex periodic structure is proposed. A double gradient spoof surface plasmon polaritons structure is added to the standard microstrip line for reducing the antenna size. The miniaturization of the proposed antenna is analyzed with the method of dispersion curves and electric field distribution. Periodic changes of the groove depth and trapezoidal gradient structure increase the beam scanning angle from backward to forward and suppress the open stopband effect. The proposed structure is printed on the FR-4 substrate with a compact size of 0.23λ0 × 3.71λ0 (λ0 is the wavelength of the lowest operating frequency), and has a working frequency band from 12.5 to 42.5 GHz for |S11| < −10 dB. Meanwhile, a wide beam-scanning angle of 142° (−52° to +90°) and an average gain of 7.9 dBi are obtained by simulation and measurement. The proposed leaky-wave antenna has a potential application in wireless communication system due to its small size, broad frequency band, wide beam scanning angle and low cost.

Purpose Artificial intelligence (AI) can detect diabetic macular edema (DME) from optical coherence tomography (OCT) images. We aimed to evaluate the performance of deep learning neural networks in DME detection.Methods Embase, Pubmed, the Cochrane Library, and IEEE Xplore were searched up to August 14, 2021. We included studies using deep learning algorithms to detect DME from OCT images. Two reviewers extracted the data independently, and the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool was applied to assess the risk of bias. The study is reported according to Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies (PRISMA-DTA).Results Ninteen studies involving 41005 subjects were included. The pooled sensitivity and specificity were 96.0% (95% confidence interval (CI): 93.9% to 97.3%) and 99.3% (95% CI: 98.2% to 99.7%), respectively. Subgroup analyses found that data set selection, sample size of training set and the choice of OCT devices contributed to the heterogeneity (all P< 0.05). While there was no association between the diagnostic accuracy and transfer learning adoption or image management (all P> 0.05).Conclusions Deep learning methods, particularly the convolutional neural networks (CNNs) could effectively detect clinically significant DME, which can provide referral suggestions to the patients.

A commercial process to manufacture sotorasib (AMG 510), a first-in-class KRASG12Cinhibitor, is described. Development efforts focused on rendering a fit-for-purpose early-phase route into a viable long-term commercial process through the reduction of side reactions to improve yield and product quality, as well as reducing cycle times of crystallization processes by improving particle properties and filtration times. These improvements were key to ensuring clinical supply and commercial launch. The final route consists of five synthetic operations from starting material M-1, including a telescoped two-step sequence, and a final form-setting crystallization.

An organocatalyzed, formal (3+3) cycloaddition reaction is described for the practical synthesis of substituted pyridines. Starting from readily available enamines and enal/ynal/enone substrates, the protocol affords tri- or tetrasubstituted pyridine scaffolds bearing various functional groups. This method was demonstrated on a 50 g scale, enabling the synthesis of 2-isopropyl-4-methylpyridin-3-amine, a raw material used for the manufacture of sotorasib. Mechanistic analysis using two-dimensional nuclear magnetic resonance (NMR) spectrometry revealed the transformation proceeds through the reversible formation of a stable reaction off-cycle species that precedes pyridine formation. In situreaction progress kinetic analysis and control NMR studies were employed to better understand the role of FeCl3and pyrrolidine hydrochloride in promoting the reaction.

Objective: To investigate practice patterns and clinical outcomes in the repair of uncomplicated rhegmatogenous retinal detachments (RRD) in a real-world setting over a 10-year period. Methods: We compared preferences for scleral buckling (SB), pars plana vitrectomy (PPV), PPV/SB, or pneumatic retinopexy (PR) over time, and examined the 1-year single surgery anatomic success (SSAS) and best-corrected visual acuity (BCVA) at a tertiary academic institution from 2008–2018. Results: Eight hundred eight eyes had RRD repair between 2008–2011 (n= 240), 2012–2014 (n= 271), and 2015–2017 (n= 297). Compared to 2008–2011, PPV was preferred over SB in 2012–2014 (OR: 2.93; 95% CI: 1.86–4.63) and 2015–2017 (OR: 5.94; 95% CI: 3.76–9.38), and over PPV/SB in 2012–2014 (OR: 2.74; 95% CI: 1.65–4.56) and 2015–2017 (OR: 3.16; 95% CI: 31.96–5.12). PR was uncommonly utilized (&lt;10%). Younger surgeons (graduating 2010–2017) favored PPV over SB when compared to older surgeons [graduating 1984–2000 (OR: 1.77; 95% CI: 1.18–2.65) and 2001–2009 (OR 1.73; 95% CI: 1.14–2.65)], but similarly selected PPV vs. PPV/SB as their older counterparts (p> 0.05). Compared to PPV, SSAS was higher with SB (OR: 1.53; 95% CI: 1.03–2.26) and PPV/SB (OR: 2.55; 95% CI: 1.56–4.17). One-year BCVA was markedly improved compared to baseline only for eyes that achieved SSAS (p&lt; 0.001). Conclusions: Over the past 10 years, PPV has become the favored approach to repair uncomplicated RRD and this appears to be driven by younger surgeons’ preferences. Given the superior long-term SSAS in SB and PPV/SB as compared to PPV, SB and PPV/SB should be more frequently considered when determining the appropriate repair strategy for uncomplicated RRD.

Objective: Effective delivery of discharge instructions and access to postoperative care play a critical role in outcomes after pediatric surgery. Previous studies in the pediatric emergency department suggest that caregivers with language barriers have less comprehension of discharge instructions despite use of interpretation services. However, the impact of language barriers during discharge on surgical outcomes in a pediatric surgical setting has not been studied. This study examined the effect of parental language during discharge on number and mode of healthcare contact following pediatric adenotonsillectomy.Methods: A retrospective cohort study was conducted on children who underwent adenotonsillectomy at a tertiary care pediatric academic medical center from July 1, 2016 to June 1, 2018. Data were collected on consecutive patients with non-English-speaking caregivers and a systematic sampling of patients with English-speaking caregiver. Surgery-related complications and healthcare contacts within 90 days after discharge were collected. Two-tailed ttests, χ2tests, and logistic regression were performed to assess the association between parental primary language and incidence of healthcare contact after surgery.Results: A total of 136 patients were included: 85 English-speaking and 51 non-English-speaking. The groups were comparable in age, sex, and comorbidities. The non-English group had more patients with public insurance (86% vs. 56%; P< .001). Number of encounters and types of complications following discharge were similar, but the non-English group was more likely to utilize the emergency department compared to phone calls (OR, 9.3; 95% CI, 2.3-38.2), even after adjustment for insurance type (OR, 7.9; 95% CI, 1.6-39.4).Conclusion: Language barriers at discharge following pediatric otolaryngology surgery is associated with a meaningful difference in how patients utilized medical care. Interventions to improve comprehension and access may help reduce preventable emergency department visits and healthcare costs.

Our understanding of how human embryos develop before gastrulation, including spatial self-organization and cell type ontogeny, remains limited by available two-dimensional technological platforms1,2that do not recapitulate the in vivo conditions3–5. Here we report a three-dimensional (3D) blastocyst-culture system that enables human blastocyst development up to the primitive streak anlage stage. These 3D embryos mimic developmental landmarks and 3D architectures in vivo, including the embryonic disc, amnion, basement membrane, primary and primate unique secondary yolk sac, formation of anterior–posterior polarity and primitive streak anlage. Using single-cell transcriptome profiling, we delineate ontology and regulatory networks that underlie the segregation of epiblast, primitive endoderm and trophoblast. Compared with epiblasts, the amniotic epithelium shows unique and characteristic phenotypes. After implantation, specific pathways and transcription factors trigger the differentiation of cytotrophoblasts, extravillous cytotrophoblasts and syncytiotrophoblasts. Epiblasts undergo a transition to pluripotency upon implantation, and the transcriptome of these cells is maintained until the generation of the primitive streak anlage. These developmental processes are driven by different pluripotency factors. Together, findings from our 3D-culture approach help to determine the molecular and morphogenetic developmental landscape that occurs during human embryogenesis.

Drug repositioning, or the identification of new indications for approved therapeutic drugs, has gained substantial traction with both academics and pharmaceutical companies because it reduces the cost and duration of the drug development pipeline and the likelihood of unforeseen adverse events. To date there has not been a systematic effort to identify such opportunities, in part because of the lack of a comprehensive resource for an enormous amount of unsystematic drug repositioning information to support scientists who could benefit from this endeavor. To address this challenge, we developed a new database, the Experimental Knowledge-Based Drug Repositioning Database (EK-DRD), by using text and data mining as well as manual curation. EK-DRD contains experimentally validated drug repositioning annotation for 1861 FDA-approved and 102 withdrawn small-molecule drugs. Annotation was done at four levels using 30 944 target assay records, 3999 cell assay records, 585 organism assay records, and 8889 clinical trial records. Additionally, approximately 1799 repositioning protein or target sequences coupled with 856 related diseases and 1332 pathways are linked to the drug entries. Our web-based software displays a network of integrative relationships between drugs, their repositioning targets, and related diseases. The database is fully searchable and supports extensive text, sequence, chemical structure, and relational query searches. EK-DRD is freely accessible at http://www.idruglab.com/drd/index.php.

A highly regio- and enantioselective synthesis of 1,2-diamine derivatives from γ-substituted allylic pivalamides using copper-catalyzed hydroamination is reported. The N-pivaloyl group is essential, in both facilitating the hydrocupration step and suppressing an unproductive β-elimination from the alkylcopper intermediate. This approach enables an efficient construction of chiral differentially protected vicinal diamines under mild conditions with broad functional group tolerance.

The existence of topological hinge states is a key signature for a newly proposed class of topological matter, the second-order topological insulators. In the present paper, a universal mechanism to generate chiral hinge states in the ferromagnetic axion insulator phase is introduced, which leads to an exotic transport phenomenon, the quantum anomalous Hall effect (QAHE) on some particular surfaces determined by both the crystalline symmetry and the magnetization direction. A realistic material system, Sm-doped Bi2Se3, is then proposed to realize such exotic hinge states by combining first-principles calculations and Green’s function techniques. A physically accessible way to manipulate the surface QAHE is also proposed, which makes it very different from the QAHE in ordinary 2D systems.

Two-dimensional transition metal dichalcogenides (TMDCs) are recently emerged electronic systems with various novel properties, such as spin-valley locking, circular dichroism, valley Hall effect, and superconductivity. The reduced dimensionality and large effective masses further produce unconventional many-body interaction effects. Here we reveal strong interaction effects in the conduction band of MoS2by transport experiment. We study the massive Dirac electron Landau levels (LL) in high-quality MoS2samples with field-effect mobilities of 24 000 cm2/(V·s) at 1.2 K. We identify the valley-resolved LLs and low-lying polarized LLs using the Lifshitz–Kosevitch formula. By further tracing the LL crossings in the Landau fan diagram, we unambiguously determine the density-dependent valley susceptibility and the interaction enhanced g-factor from 12.7 to 23.6. Near integer ratios of Zeeman-to-cyclotron energies, we discover LL anticrossings due to the formation of quantum Hall Ising ferromagnets, the valley polarizations of which appear to be reversible by tuning the density or an in-plane magnetic field. Our results provide evidence for many-body interaction effects in the conduction band of MoS2and establish a fertile ground for exploring strongly correlated phenomena of massive Dirac electrons.

Revealing the role of Coulomb interaction in topological semimetals with Dirac/Weyl-like band dispersion shapes a new frontier in condensed matter physics. Topological node-line semimetals (TNLSMs), anticipated as a fertile ground for exploring electronic correlation effects due to the anisotropy associated with their node-line structure, have recently attracted considerable attention. In this study, we report an experimental observation for correlation effects in TNLSMs realized by black phosphorus (BP) under hydrostatic pressure. By performing a combination of nuclear magnetic resonance measurements and band calculations on compressed BP, a magnetic-field-induced electronic instability of Weyl-like fermions is identified under an external magnetic field parallel to the so-called nodal ring in the reciprocal space. Anomalous spin fluctuations serving as the fingerprint of electronic instability are observed at low temperatures, and they are observed to maximize at approximately 1.0 GPa. This study presents compressed BP as a realistic material platform for exploring the rich physics in strongly coupled Weyl-like fermions.

We report on emergence of an abnormal electronic polarization in twisted double bilayer WSe2in antiparallel interface stacking geometry, where local centrosymmetry of atomic registries at the twist interface does not favor the spontaneous electronic polarizations as recently observed in the parallel interface stacking geometry. The unconventional ferroelectric behaviors probed by electronic transport measurement occur at half filling insulating states at 1.5 K and gradually disappear at about 40 K. Single band Hubbard model based on the triangular moiré lattice and the interlayer charge transfer controlled by insulating phase transition are proposed to interpret the formation of electronic polarization states near half filling in twisted WSe2devices. Our work highlights the prominent role of many-body electronic interaction in fostering novel quantum states in moiré-structured systems.

Intriguing physical properties of materials stem from their chemical constituents, whereas the connection between them is often not clear. Here, we uncover a general chemical classification for the two quantum phases in the honeycomb ABX structure—topological insulator (TI) and topological Dirac semimetal (TDSM). First, we find among the 816 (existing as well as hypothetical) calculated compounds, 160 TIs (none were noted before), 96 TDSMs, 282 normal insulators (NIs), and 278 metals. Second, based on this classification, we have distilled a simple chemical regularity based on compound formulas for the selectivity between TI and TDSM: the ABX compounds that are TDSM have B atoms (part of the BX honeycomb layers) that come from the periodic table columns XI (Cu, Ag, Au) or XII (Zn, Cd, Hg), or Mg (group II), whereas the ABX compounds whose B atoms come from columns I (Li, Na, K, Rb, Cs) or II (Ca, Sr, Ba) are TIs. Third, focusing on the ABX bismide compounds that are thermodynamically stable, we find a structural motif that delivers topological insulation and stability at the same time. This study opens the way to simultaneously design new topological materials based on the compositional rules indicated here.

Dysbiosis, departure of the gut microbiome from a healthy state, has been suggested to be a powerful biomarker of disease incidence and progression1–3. Diagnostic applications have been proposed for inflammatory bowel disease diagnosis and prognosis4, colorectal cancer prescreening5and therapeutic choices in melanoma6. Noninvasive sampling could facilitate large-scale public health applications, including early diagnosis and risk assessment in metabolic7and cardiovascular diseases8. To understand the generalizability of microbiota-based diagnostic models of metabolic disease, we characterized the gut microbiota of 7,009 individuals from 14 districts within 1 province in China. Among phenotypes, host location showed the strongest associations with microbiota variations. Microbiota-based metabolic disease models developed in one location failed when used elsewhere, suggesting that such models cannot be extrapolated. Interpolated models performed much better, especially in diseases with obvious microbiota-related characteristics. Interpolation efficiency decreased as geographic scale increased, indicating a need to build localized baseline and disease models to predict metabolic risks. The definition of a 'healthy' microbiome is impacted by geographic regional variations.

The lithium sulfur (Li–S) battery has attracted much attention due to its high theoretical capacity and energy density. However, its cycling stability and rate performance urgently need to improve because of its shuttle effect. Herein, oxygen-doped carbon on the surface of reduced graphene oxide (labeled as ODC/rGO) was fabricated to modify the separators of Li–S batteries to limit the dissolution of the lithium polysulfides. The mesoporous structure in ODC/rGO can not only serve as the physical trapper, but also provide abundant channels for fast ion transfer, which is beneficial for effective confinement of the dissoluble intermediates and superior rate performance. Moreover, the oxygen-containing groups in ODC/rGO are able to act as chemical adsorption sites to immobilize the lithium polysulfides, suppressing their dissolution in electrolyte to enhance the utilization of sulfur cathode in Li–S batteries. As a result, because of the synergetic effects of physical adsorption and chemical interaction to immobilize the soluble polysulfides, the Li–S batteries with the ODC/rGO-coated separator exhibit excellent rate performance and good long-term cycling stability with 0.057% capacity decay per cycle at 1.0 C after 600 cycles.

Nucleophilic addition reactions of organometallic reagents to carbonyl compounds for carbon–carbon bond construction have played a pivotal role in modern chemistry. However, this reaction's reliance on petroleum-derived chemical feedstocks and a stoichiometric quantity of metal have prompted the development of many carbanion equivalents and catalytic metal alternatives. Here, we show that naturally occurring carbonyls can be used as latent alkyl carbanion equivalents for additions to carbonyl compounds, via reductive polarity reversal. Such ‘umpolung’ reactivity is facilitated by a ruthenium catalyst and diphosphine ligand under mild conditions, delivering synthetically valuable secondary and tertiary alcohols in up to 98% yield. The unique chemoselectivity exhibited by carbonyl-derived carbanion equivalents is demonstrated by their tolerance to protic reaction media and good functional group compatibility. Enantioenriched tertiary alcohols can also be accessed with the aid of chiral ligands, albeit with moderate stereocontrol. Such carbonyl-derived carbanion equivalents are anticipated to find broad utility in chemical bond formation.

Using advanced two-photon excitation confocal microscopy, associated with time-resolved spectroscopy, we characterize InGaN/GaN multiple quantum wells on nanorod heterostructures and demonstrate the passivation effect of a KOH treatment. High-quality InGaN/GaN nanorods were fabricated using nanosphere lithography as a candidate material for light-emitting diode devices. The depth- and time-resolved characterization at the nanoscale provides detailed carrier dynamic analysis helpful for understanding the optical properties. The nanoscale spatially resolved images of InGaN quantum well and defects were acquired simultaneously. We demonstrate that nanorod etching improves light extraction efficiency, and a proper KOH treatment has been found to reduce the surface defects efficiently and enhance the luminescence. The optical characterization techniques provide depth-resolved and time-resolved carrier dynamics with nanoscale spatially resolved mapping, which is crucial for a comprehensive and thorough understanding of nanostructured materials and provides novel insight into the improvement of materials fabrication and applications.

Cloud forming by solid explosive dispersal plays a decisive factor for twice-detonating FAE. The study of the flow field of internal cloud field can be more intuitive to understand the whole process of the formation of cloud diffusion, and it also has an important role to the delay time setting of secondary detonating fuze. Internal parameters of spreading cloud are difficult to obtain even through by the experiment method, but numerical analysis and simulations method can get the parameter. In this paper, we use experimental and simulation methods to study fuel dispersal process, aims to establish an effective and reliable mathematical models of cloud dispersal, and get the model data coinciding with the real situation.

In this paper we used the MEMS microphone to detect the sound position. A four–microphone array was constructed to localize sound source with Time Difference of Arrival (TDoA) measurements based on hyperbola model. The time delay was calculated using Generalized Cross Correlation (GCC) algorithm. A practical test system was built to confirm the feasibility of the hyperbola model and GCC algorithm using MEMS microphone. Data were collected in field experiments and calculated on PC by matlab. The results show that the method instructed in this paper is feasible in localizing the sound position with MEMS microphone.

Shutters-style shielding and protective device for windscreen is the shutters installed outside the external position of the vehicle windscreen with the function of shelter and protection. It does not only avoid the enemy reconnaissance due to the reflective glass, but also withstands the damage from all kinds of bullets and shrapnel, and it does not affect the normal running of the vehicle.

According to the principle of electromagnetic wave propagation and the model of radar multipath propagation, this paper established radar detection power model in natural space under the impact of sea clutter, and on condition that conducting simulations to study detection power of shore-based radars on different altitudes and different operating frequencies. Simulation results indicate that when the radar operating frequency is constant, with the erection height increases, the detection range will increase at the same time, while significantly reduced about blind region. When the radar erection height is constant, blind region is filled with radars working at C, S and X operating frequencies. The effect of blind filling is of great importance for adjacent bands. This paper provides theoretical reference analysis for radar detection power assessing and overall with a strong engineering application value.

The class of topological insulator materials is one of the frontier topics of condensed matter physics. The great success of this field is due to the conceptual breakthroughs in theories for topological electronic states and is strongly motivated by the rich variety of material realizations, thus making the theories testable, the experiments operable, and the applications possible. First-principles calculations have demonstrated unprecedented predictive power for material selection and design. In this article, we review recent progress in this field with a focus on the role of first-principles calculations. In particular, we introduce the Wilson loop method for the determination of topological invariants and discuss the band inversion mechanism for the selection of topological materials. Recent progress in quantum anomalous Hall insulators, large-gap quantum spin Hall insulators, and correlated topological insulators is also covered.

The rapid development of electronic technology has produced numerous demands, which have generated a new-born industry--EMS. In EMS corporations, purchase cost is a large proportion of total costs, so purchase cost control is one of the key competitiveness for EMS. Analytic Hierarchy Process (AHP) help EMS solve the problem of purchase cost control.

Suspend-dome structure form which colligates advantages of cable dome and reticulated shell is a new type spatial hybrid structure system. This article introduced the configuration and principle of suspend-dome structure system, and researched the structural behavior influence by altering the joint stiffness, vector height of the suspend-dome and the loop cable pretension. The results show that suspend-dome structure should make comprehensive consideration on interaction between vector height, prestress application and other factors, and relevant optimizing design method can be adopted in the design.

Red Spider software is introduced in line with the features of multimedia network teaching. First introduced are the features of Red Spider software, and then described are the main functions of the software. Finally, several problems concerning practical application are listed out.

This paper makes analysis of new types of Vehicles and life-cycle cost distribution according to new typed of vehicle structure, and then makes analysis of the use intensity and the degrees of aging of new types of Vehicles, at last this paper proposes a new use control strategy.

This paper analyzes the basic combustion characteristics of dual-fuel engine with diesel-natural gas, including the engine’s running characteristics, the external characteristics and the low-load performance. Taking the development and application of natural gas for consideration, this paper also makes studies on how to improve the dynamic performance of the dual-fuel engine CA6110ZLA5N2.

An experimental study is made on the emission of a single-cylinder direct injection diesel engine with different proportions of GDE and diesel. The study shows the mechanism when GDE is added to diesel to reduce diesel emission. And an analysis of pollutant emission is made on the regularities of variation with engine load changes. The results show that the addition of diesel oil in the volume fraction of 10% to 20% of GDE can significantly increase the thermal efficiency, shorten the duration of diesel combustion, substantially decrease carbon smoke and CO in emission under the high-load conditions and slightly lessen the NOx emission, but HC emission still remain basically unchanged.