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In pursuing high stability and power conversion efficiency for organic photovoltaics (OPVs), a sequential deposition (SD) approach to fabricate active layers with p–i–n structures (where p, i, and n represent the electron donor, mixed donor:acceptor, and electron acceptor regions, respectively, distinctively different from the bulk heterojunction (BHJ) structure) has emerged. Here, we present a novel approach that by incorporating two polymer donors, PBDBT-DTBTand PTQ-2F, and one small-molecule acceptor, BTP-3-EH-4Cl, into the active layer with sequential deposition, we formed a device with nanometer-scale twin p–i–n structured active layer. The twin p–i–n PBDBT-DTBT:PTQ-2F/BTP-3-EH-4Cldevice involved first depositing a PBDBT-DTBT:PTQ-2Fblend under layer and then a BTP-3-EH-4Cltop layer and exhibited an improved power conversion efficiency (PCE) value of 18.6%, as compared to the 16.4% for the control BHJ PBDBT-DTBT:PTQ-2F:BTP-3-EH-4Cldevice or 16.6% for the single p–i–n PBDBT-DTBT/BTP-3-EH-4Cldevice. The PCE enhancement resulted mainly from the twin p–i–n active layer’s multiple nanoscale charge carrier pathways that contributed to an improved fill factor and faster photocurrent generation based on transient absorption studies. The PBDBT-DTBT:PTQ-2F/BTP-3-EH-4Clfilm possessed a vertical twin p–i–n morphology that was revealed through secondary ion mass spectrometry and synchrotron grazing-incidence small-angle X-ray scattering analyses. The thermal stability (T80) at 85 °C of the twin p–i–n PBDBT-DTBT:PTQ-2F/BTP-3-EH-4Cldevice surpassed that of the single p–i–n PBDBT-DTBT/BTP-3-EH-4Cldevices (906 vs 196 h). This approach of providing a twin p–i–n structure in the active layer can lead to substantial enhancements in both the PCE and stability of organic photovoltaics, laying a solid foundation for future commercialization of the organic photovoltaics technology.

Linear and nonlinear impairments restrict the transmission performance of high-speed terahertz (THz) communication systems. To improve transmission performance, we propose a two-stage nonlinear equalizer (NLE). In the first stage, a memory-controlled long short-term memory (LSTM) neural network learns channel nonlinearity and compensates for it through nonlinear waveform regression. In the second stage, a low-complexity deep random forest (RF) network identifies nonlinear boundaries among individual QAM symbols and adjusts the standard hard decision thresholds of the QAM demodulator to align with the distribution of received symbols. This study experimentally validates the proposed two-stage NLE on a dual-channel THz-over-fiber transmission system using an intensity modulation and direct detection (IM/DD) scheme, achieving a successful 20 Gbps line rate up to a 4.5-meter wireless link at both 125/300 GHz frequency bands. The proposed scheme outperforms a Volterra nonlinear equalizer in all tested scenarios, surpassing a linear equalizer (LE) by reducing the bit error rate (BER) from $2.47 \times 10^{-3}$ to $2.61 \times 10^{-4}$ in the 300 GHz link and from $3.42 \times 10^{-3}$ to $5.64 \times 10^{-4}$ in the 125 GHz link.

Elevation-azimuth photoelectric survey telescopes working under long exposure station is very important for observing weak targets in space. The motion characteristics analyses including position and velocity of rotating targets show that the image stabilization system (IMSS) needs to have a self-locking capability, low temperature rise, anti-interference, high-speed switching, and ultralow-speed tracking performance. A dual-motor drive IMSS with self-locking was adopted after comparison. In this work, in order to overcome the inherent uncertainties affecting the accurate tracking of a target in a dual-motor driving gears of the IMSS, we introduce a compound control strategy including bias torque controller in current-loop and active disturbance rejection controller in velocity-loop. Experimental results show that the proposed controller can effectively eliminate backlash of IMSS, and the fixed-point control accuracy can achieve 0.18 arcs. When the sinusoidal speed guidance is 0.068 sin (2π × 0.01 × t) (°/s) and position guidance is cos (2π × 0.01 × t) (°), the position error is 0.31 arcs. After image stabilization, the imaging resolution can be guaranteed to reach within 0.5-pixel under the 60 s exposure time.

Chiral α-aminophosphonates with adjacent carbon and phosphonate stereogenic centers have been employed as ligands in the copper-catalyzed oxidative coupling of 2-naphthols, resulting in the production of chiral BINOLs in favorable yields and moderate to good enantiomeric excess. This represents the first application of chiral P-based ligands to enable such a transformation. The synthesis of these chiral α-aminophosphonate ligands offers a significant advantage over approaches that typically necessitate elaborate synthetic processes for chiral ligand production.

We have developed a Tf2O-mediated approach for the direct amination of either P(O)–OH or P(O)–H reagents with a variety of aliphatic or aromatic amines. Without the requirement of precious metals and toxic reagents, this protocol provides an alternative route to various phosphinamides and phosphoramides. The reaction proceeds under simple and mild conditions and can be effectively scaled up with similar efficiency.

Physical Vapor Deposition (PVD) of Tantalum/Tantalum Nitride (Ta/TaN) liner and barrier plays a crucial role in the copper-interconnecting part of semiconductor manufacturing, and this is used for the 130 nm–5nm technology node and beyond. This study focuses on the surface preparation and characterization of wire-arc spray directed energy deposition (DED) coating in the refurbishment process of PVD chamber kits. Spray coating adhesion strength is enhanced due to the pretreatment of the substrate with grit blasting, which creates a suitable surface texture, and the replacement of aluminum alloy as wire-arc spray DED coating material from pure aluminum (99.8%). However, it was experimentally found that using high adhesion strength coating chamber kits increases the probability of out-of-control (OOC) occurrences in the mid-stage of the kit lifetime, and the fundamental reasons may be attributed to the spiky surface morphology of wire-arc spray DED coating layers. Finite element analysis simulates stress distribution and identifies stress concentration regions within the multilayer Ta/TaN thin film using two surface morphologies with significantly different curvature radii of spray coatings. Differences in wire-arc spray DED processing parameters include a slower travel speed, a longer spray time, and a lower feed rate. It is numerically simulated and experimentally observed that coating surface morphology dramatically affects thin film delamination, which is the primary cause of particle defects. This study emphasizes the potential mechanisms for forming particle defects, improved uniformity in spray coatings, and increased surface curvature radius to minimize stress concentration.

This study considers the optimal consumption-investment-insurance problem incorporating housing decisions of a household when interest rates and labor income are stochastic. Under the complete market assumption, we derive the closed-form solution of the optimal insurance demand, portfolio choice, and housing consumption. We calibrate the model using data from the financial market of Taiwan. We find that the insurer's pricing strategy has a significant impact on the household's consumption pattern. Specifically, additional loading in insurance premium allows the life-cycle model to produce hump-shaped consumptions of both perishable goods and housing. Loading also creates an unfair background risk to households. However, we only find a small portfolio risk reduction, because households optimally choose a large coverage to mitigate the mortality exposure. This suggests empirical background risk studies overestimate the risk reduction when insurance is available., INTRODUCTION Households are exposed to a mix of risks, each with some unique characteristics. This study considers how a household should do when facing a variety of risks. Common asset [...]

Hematopoietic stem cell (HSC) transplantation, using either bone marrow (BM) or peripheral blood stem cells (PBSC), is a well-established therapy for various hematologic and non-hematologic diseases. However, the long-term health outcomes after HSC donation remain a major concern for several potential donors. Thus, we aimed to conduct a matched cohort study of 5003 unrelated donors (1099 BM and 3904 PBSC) and randomly selected 50,030 matched controls based on age, sex, and resident area from the donor registry between 1998 and 2018. The medical insurance claims of all the participants were retrieved from the Taiwan National Health and Welfare Data Science Center after de-identification. Our findings revealed no differences in the incidence of cancer, death, and catastrophic diseases between HSC donors and matched healthy participants during long-term follow-up. Kaplan–Meier curves depicting the cumulative incidence of cancer and overall mortality throughout the follow-up period also demonstrated similar outcomes between donors and non-donors. In conclusion, our results indicate that HSC donation, whether through BM or PBSC, is safe and not associated with an increased risk of cancer, death, or catastrophic diseases. These findings provide valuable information for counseling potential HSC donors and for long-term management of HSC donor health.

Ca-Mg-Zn bulk metallic glasses (BMGs) are promising biomaterials for orthopaedic applications because when they get reabsorbed, a retrieval surgery is not needed. In this study, Ca-Mg-Zn metallic glasses with different compositions, Ca56.02Mg20.26Zn23.72 and Zn50.72Mg23.44Ca25.84, were fabricated by induction melting followed by copper mould casting. Their degree of crystallinity was modified by annealing, obtaining exemplar specimens of fully amorphous, partially amorphous (i.e., a BMG composite (BMGC)) and fully crystalline alloys. The microstructure, thermodynamic and corrosion performance of these alloys were evaluated as well as their electrochemical behaviour. The results of polarisation tests demonstrate that the corrosion resistance of the Zn-rich alloy is markedly better than the Ca-rich BMG. Corrosion rates of these Ca-and Zn-rich alloys with different degrees of crystallinity illustrate that the corrosion behaviours of alloys strongly depend on their microstructure, which shows a positive correlation between the corrosion current density and the crystallised volume fraction of the alloy. This study aims to shed light on the impact of the amorphicity-to-crystallinity ratio on the multifunctional properties of BMGs/BMGCs, and to assess how feasible it is to fine-tune those properties by controlling the percentage of crystallinity.

Pressure relief is an important step in preventing and controlling rock burst disasters. Hydraulic slotting has emerged as a strategy for pressure relief and energy release in roadway surrounding rock. There is no qualitative description for the response relationship between hydraulic slotting parameters and the degree of pressure and energy release in a roadway, which is a scientific problem. In this paper, theoretical analysis, numerical simulation, and on-site industrial practice were comprehensively used. First, a structural model for the pressure relief and energy release of coal by hydraulic slotting in a deep roadway was established, and the pressure relief and energy release principle by hydraulic slotting was revealed. The principles and methods for determining hydraulic slotting parameters in the roadway were proposed. Three evaluation indices for the pressure relief and energy release effect of coal after hydraulic slotting were proposed, namely, the stress ratio of coal, elastic energy density ratio of coal, and displacement rate of the roadway rib. According to the evaluation indices, the degree of pressure relief and energy release was divided into three levels: reverse pressurization, full pressure relief, and transitional pressure relief. Then, a FLAC3Dnumerical model was constructed, the levels of pressure relief and energy release under different hydraulic slotting parameters were analyzed, and the optimal slotting parameters were determined. Finally, on-site industrial practices were carried out in Panel 7312 of the Xinhe Coal Mine. An effect test showed that the effect of pressure relief and energy release was remarkable after hydraulic slotting was adopted on the roadway surrounding rock, which can effectively reduce the risk of rock bursts. These research results can further improve hydraulic slotting technology systems and provide a theoretical basis and technical reference for the stability control of deep roadway surrounding rock.

Stimulated Raman scattering (SRS) spectromicroscopy is a powerful technique that enables label-free detection of chemical bonds with high specificity. However, the low Raman cross section due to typical far-electronic resonance excitation seriously restricts the sensitivity and undermines its application to bio-imaging. To address this bottleneck, the electronic preresonance (EPR) SRS technique has been developed to enhance the Raman signals by shifting the excitation frequency toward the molecular absorption. A fundamental weakness of the previous demonstration is the lack of dual-wavelength tunability, making EPR-SRS only applicable to a limited number of species in the proof-of-concept experiment. Here, we demonstrate the EPR-SRS spectromicroscopy using a multiple-plate continuum (MPC) light source able to examine a single vibration mode with independently adjustable pump and Stokes wavelengths. In our experiments, the C═C vibration mode of Alexa 635 is interrogated by continuously scanning the pump-to-absorption frequency detuning throughout the entire EPR region enabled by MPC. The results exhibit 150-fold SRS signal enhancement and good agreement with the Albrecht A-term preresonance model. Signal enhancement is also observed in EPR-SRS images of the whole Drosophilabrain stained with Alexa 635. With the improved sensitivity and potential to implement hyperspectral measurement, we envision that MPC-EPR-SRS spectromicroscopy can bring the Raman techniques closer to a routine in bio-imaging.

In adopting a traditional actuarial view, insurance companies often use expected values to determine the premiums for lifetime health insurance policies with limited coverage, which can lead to serious overpricing problems when the coverage limit is not very low or very high. To address this overpricing problem, this article provides analytical solutions for fair premiums of lifetime health insurance policies with limited coverage. Using internal data provided by insurance companies, this article describes the relationship between the level of limited coverage and excess premiums. The premium difference between a practical pricing method and a proposed pricing model creates a humped curve; the maximum excess premium ratio reaches nearly 20 percent for limited coverage for younger insured people., INTRODUCTION The populations of many developed countries are aging significantly, due to lower mortality and fertility rates. Continued increases in longevity contribute to rising medical costs and greater demand in [...]

The traditional methods for the synthesis of phosphinate esters use phosphorus trichloride (PCl3) as the phosphorous source, resulting in procedures that are often highly polluting and energy intensive. The search for an alternative approach that is both mild and environmentally friendly is a challenging, yet highly rewarding task in modern chemistry. Herein, we use an inorganic phosphorous-containing species, NaH2PO2, to serve as the source of phosphorous that participates directly in the nickel-catalyzed selective alkyne hydrophosphonylation reaction. The transformation was achieved in a multicomponent fashion and at room temperature, and most importantly, the H-phosphinate product generated is an advanced intermediate which can be readily converted into diverse phosphinate derivatives, including those bearing new P–C, P–S, P–N, P–Se, and P–O bonds, thus providing a complimentary method to classic phosphinate ester synthesis techniques.

P-Chiral phosphines and sec-phosphine oxides (SPO) are found in a diverse range of compounds that play crucial roles in various fields, including asymmetric catalysis, materials, agrochemistry, and pharmaceutical chemistry. Herein, we describe an enantioselective Ni-catalyzed kinetic resolution of racemic sec-phosphine oxides to obtain the corresponding optically pure P-chiral phosphine oxides and sec-phosphine oxides, respectively. These products are versatile chiral phosphine building blocks that can be used to construct an extensive range of P-chiral phosphines.

Visualizing information inside objects is an everlasting need to bridge the world from physics, chemistry, and biology to computation. Among all tomographic techniques, terahertz (THz) computational imaging has demonstrated its unique sensing features to digitalize multidimensional object information in a nondestructive, nonionizing, and noninvasive way. Applying modern signal processing and physics-guided modalities, THz computational imaging systems have now been launched in various application fields in industrial inspection, security screening, chemical inspection, and nondestructive evaluation. In this article, we review recent advances in THz computational imaging modalities in the aspects of system configuration; wave propagation and interaction models; and physics-guided algorithms for digitalizing interior information of imaged objects. Several image restoration and reconstruction issues based on multidimensional THz signals are further discussed, which provides a crosslink among material digitalization, functional property extraction, and multidimensional imager utilization from a signal processing perspective.

This letter presents a low-power current-reuse and device-reuse low noise amplifier (LNA) for sub-GHz wideband applications. Based on the shunt-feedback common-gate (SFBCG) hybrid topology and the proposed current/device-reuse shunt-feedback (SFB) technique, $g_{m}$ restriction is alleviated. Moreover, the degree of design freedom is added by coupling the output to the gate of the in-phase current source transistor to activate positive feedback without extra power burden, thereby achieving a higher gain and lower noise design. Implemented in 90-nm CMOS technology, this LNA prototype has an active area of 0.075 mm2. The measurement results show a peak gain of 21.3 dB with 3-dB bandwidth of 50–800 MHz, noise figure of 4.5 dB, third-order intercept point (IIP3) of −7.1 dBm, and power dissipation of 1.2 mW.

An efficient and facile visible-light-mediated tandem difluoromethylation/cyclization of alkenyl aldehydes, with easily accessible and air-stable [Ph3PCF2H]+Br–as the difluoromethylation reagent, has been established. A range of CF2H-substituted chroman-4-one skeletons and their derivatives, such as 2,3-dihydroquinolin-4(1H)-ones, chroman, 3,4-dihydronaphthalen-1(2H)-one, 2,3-dihydrobenzofuran, and 2,3-dihydro-1H-inden-1-one, are efficiently produced in moderate to good yields with excellent chemoselectivity under mild reaction conditions.

A facile and efficient method for the synthesis of primary phosphinamides from Ar2P(O)–H reagents with stable and readily available ammonium carbonate as an ammonia source is disclosed herein for the first time. This ethyl bromoacetate-mediated primary amination proceeds smoothly under mild and simple conditions, without any metal catalyst or oxidant. Moreover, this method is also appropriate for the reaction of Ar2P(O)–H with a variety of amines, alcohols, and phenols to construct P–N or P–O bonds, with features of handy operation, good functional group tolerance, and broad substrate scope.

Background: Acute cholecystitis (AC) is a common surgical emergency. The Tokyo Guidelines 2018 (TG18) provides a reliable algorithm for the treatment of AC patients to achieve optimal outcomes. However, the economic benefits have not been validated. We hypothesize that good outcomes and cost savings can both be achieved if patients are treated according to the TG18. Method: This retrospective study included 275 patients who underwent cholecystectomy in a 15-month span. Patients were divided into three groups (group 1: mild AC; group 2: moderate AC with American Society of Anesthesiologists (ASA) physical status class ≤ 2 and Charlson Comorbidity Index (CCI) score ≤ 5; and group 3: moderate AC with ASA class ≥ 3, CCI score ≥ 6, or severe AC). Each group was further divided into two subgroups according to management (followed or deviated from the TG18). Patient demographics, clinical outcomes, and hospital costs were compared. Results: For group 1 patients, 77 (81%) were treated according to the TG18 and had a significantly higher successful laparoscopic cholecystectomy (LC) rate (100%), lower hospital cost ($1896 vs $2388), and shorter hospital stay (2.9 vs 8 days) than those whose treatment deviated from the TG18. For group 2 patients, 50 (67%) were treated according to the TG18 and had a significantly lower hospital cost ($1926 vs $2856), shorter hospital stay (3.9 vs 9.9 days), and lower complication rate (0% vs 12.5%). For group 3 patients, 62 (58%) were treated according to the TG18 and had a significantly lower intensive care unit (ICU) admission rate (9.7% vs 25%), but a longer hospital stay (12.6 vs 7.8 days). However, their hospital costs were similar. Early LC in group 3 patients did not have economic benefits over gallbladder drainage and delayed LC. Conclusion: The TG18 are the state-of-the-art guidelines for the treatment of AC, achieving both satisfactory outcomes and cost-effectiveness.

Prodigiosin is a secondary metabolite mainly produced at 30 °C in Serratia marcescens, but it can hardly be synthetized at 37 °C or higher. In this study, we provide insight into the metabolic regulation of prodigiosin synthesis in response to temperature through transcriptome sequencing. The analysis of the function of differentially expressed genes suggested that temperature resulted in significant alteration of the metabolic pathways between 30 and 37 °C. Specifically, 30 °C favored transcriptional expression of the piggene cluster. At the same time, the carbon flux was redistributed to pathways of pyruvate, proline, serine, especially homoserine, cystathionine, homocysteine, methionine, and s-adenosylmethionine metabolism, all involved in prodigiosin biosynthesis, and was finally increased towards the prodigiosin synthesis pathway in S. marcescensat 30 °C. Interestingly, results further confirmed increased transcriptional level of five regulators (LuxS, RpoS, Hfq, EepR, CRP), and decreased content of hexSthrough qPCR. Finally, successful co-overexpression of mmuMand metK, related to homocysteine, methionine, and s-adenosylmethionine metabolism, in the chromosome of JNB5-1 (JNB5-1/MK) resulted in increased prodigiosin titer up to 7.57 g/L in JNB5-1/MK at 30 °C, which was 41.2% higher than that in JNB5-1. Our transcriptome analysis provides further insight into the strain's response to temperature changes at the transcription level, which is of great significance for improving the production of prodigiosin.

With the increase of drilling depth, the mechanical properties of H-section steel used in drilling platform are more and more demanding. In this paper, the strength, low temperature impact toughness, plasticity, micro-hardness and microstructure of 500MPa hot rolled H-section steel produced by TMCP process were analyzed, and the strengthening mechanism was also studied. The results show that flanges of TMCP hot rolled H-section steel had the best strength and toughness, while the yield strength at web and R Angle was reduced to 91% and 78% of the flange, respectively. The impact toughness at -40°C of web and R Angle was reduced to 86% and 38% of the flange , and the micro-hardness reduced to 91% and 85% of the flange, respectively. The main strengthening mechanism of the TMCP hot rolled H-section steel is fine-grain strengthening, the carbonitride of V precipitation strengthening and surface bainite transformation strengthening.

A Tf2O/DMSO-based system for the dehydrogenative coupling of a wide range of alcohols, phenols, thiols, and thiophenols with diverse phosphorus reagents has been developed. This metal- and strong-oxidant-free strategy provides a facile approach to a great variety of organophosphinates and thiophosphates. The simple reaction system, good functional-group tolerance, and broad substrate scope enable the application of this method to the modification of natural products and the direct synthesis of bioactive molecules and flame retardants.

Butachlor is widely used in agriculture around the world and therefore poses environmental and public health hazards due to persistent and poor biodegradability. Ferroptosis is a type of iron-mediated cell death controlled by glutathione (GSH) and GPX4 inhibition. P62 is an essential autophagy adaptor that regulates Keap1 to activate nuclear factor erythroid 2-related factor 2 (Nrf2), which effectively suppresses lipid peroxidation, thereby relieving ferroptosis. Here, we found that butachlor caused changes in splenic macrophage structure, especially impaired mitochondrial morphology with disordered structure, which is suggestive of the occurrence of ferroptosis. This was further confirmed by the detection of iron metabolism, the GSH system, and lipid peroxidation. Mechanistically, butachlor suppressed the protein level of p62 and promoted Keap1-mediated degradation of Nrf2, which results in decreased GPX4 expression and accelerated splenic macrophage ferroptosis. These findings suggest that targeting the p62-Nrf2-GPX4 signaling axis may be a promising strategy for treating inflammatory diseases.

A novel series of excited-state intramolecular proton transfer (ESIPT) emitters, namely, DPNA, DPNA-F, and DPNA-tBu, endowed with dual intramolecular hydrogen bonds, were designed and synthesized. In the condensed phase, DPNAsexhibit unmatched absorption and emission spectral features, where the minor 0–0 absorption peak becomes a major one in the emission. Detailed spectroscopic and dynamic approaches conclude fast ground-state equilibrium among enol–enol (EE), enol–keto (EK), and keto–keto (KK) isomers. The equilibrium ratio can be fine-tuned by varying the substitutions in DPNAs. Independent of isomers and excitation wavelength, ultrafast ESIPT takes place for all DPNAs, giving solely KK tautomer emission maximized at >650 nm. The spectral temporal evolution of ESIPT was resolved by a state-of-the-art technique, namely, the transient grating photoluminescence (TGPL), where the rate of EK* → KK* is measured to be (157 fs)−1for DPNA-tBu, while a stepwise process is resolved for EE* → EK* → KK*, with a rate of EE* → EK* of (72 fs)−1. For all DPNAs, the KK tautomer emission shows a narrowband emission with high photoluminescence quantum yields (PLQY, ∼62% for DPNAin toluene) in the red, offering advantages to fabricate deep-red organic light-emitting diodes (OLED). The resulting OLEDs give high external quantum efficiency with a spectral full width at half-maximum (FWHM) as narrow as ∼40 nm centered at 666–670 nm for DPNAs, fully satisfying the BT. 2020 standard. The unique ESIPT properties and highly intense tautomer emission with a small fwhm thus establish a benchmark for reaching red narrowband organic electroluminescence.

A novel and selective method of simple copper-salt catalyzed phosphonation of α-amino carbonyl compounds to afford imidoylphosphonates is reported. This reaction system has a broad reaction scope. The convenient and environmentally benign process makes this protocol very attractive.

1,3-Propanediol, traditionally obtained from fossils, has numerous industrial applications, including use in the production of high performance polymers. The microbial production of 1,3-propanediol presents several opportunities, and the final purity grade determines its price and commercial viability. The development of novel separation technology could improve the economic viability of the bioproduction of 1,3-propanediol. Thus, we investigated salting-out extraction as a novel process for 1,3-propanediol recovery from fermentation broth. Initially, a screening for the best salt/solvent combination was conducted and then optimized using the response surface methodology. The solvents studied were methanol, ethanol, isopropanol and acetone, and the salts examined were K2HPO4, Na2CO3, K2CO3, (NH4)2SO4, NaHPO4, K3PO4and C6H5NaO7. The optimal extraction system consisted of 34wt% K3PO4, 28wt% ethanol, and 38wt% fermentation broth containing 23.0g·L−11,3-propanediol, which gave the highest partition coefficient of 33 and recovery yield of 97%. The results demonstrated that salting-out extraction was a promising method for 1,3-propanediol recovery from fermentation broth.

A new approach to the synthesis of 2-phosphinoylindoles through photoredox catalysis without external oxidants has been developed. Promoted by a ruthenium photoredox catalyst, a broad scope of 2-phosphinoylindoles can be synthesized through phosphinoylation/cyclization of diphenylphosphine oxide at room temperature under irradiation without external oxidants. The estrone skeleton isocyan is also an amenable substrate for this cyclization, yielding a molecule that has potential medicinal applications.

Large supply voltage ripple will cause the Internet-of-Things (IoT) operation to fail. Conventional bulky clamp circuit simply eliminates overshoot redundant energy but with reduced efficiency. In this article, the multiphase active energy recycling (MP-AER) technique uses an active recovery mechanism with multiple 33-nH bond wires to recycle energy from the overshoot voltage for increasing efficiency. The experimental results show that when the load current in the IoT application suddenly drops from 1.7 to 0.3 A, the ultrafast energy recovery of 47.1 mW/μs suppresses the output overshoot voltage from 507 to 95 mV, an increase of 81.3%. The energy recovered by the MP-AER technique achieves a peak efficiency of 93% when the input voltage is 3 V and the loading current is 300 mA.

Transient neuromodulation can have long-lasting effects on neural circuits and motivational states1–4. Here we examine the dopaminergic mechanisms that underlie mating drive and its persistence in male mice. Brief investigation of females primes a male’s interest to mate for tens of minutes, whereas a single successful mating triggers satiety that gradually recovers over days5. We found that both processes are controlled by specialized anteroventral and preoptic periventricular (AVPV/PVpo) dopamine neurons in the hypothalamus. During the investigation of females, dopamine is transiently released in the medial preoptic area (MPOA)—an area that is critical for mating behaviours. Optogenetic stimulation of AVPV/PVpo dopamine axons in the MPOA recapitulates the priming effect of exposure to a female. Using optical and molecular methods for tracking and manipulating intracellular signalling, we show that this priming effect emerges from the accumulation of mating-related dopamine signals in the MPOA through the accrual of cyclic adenosine monophosphate levels and protein kinase A activity. Dopamine transients in the MPOA are abolished after a successful mating, which is likely to ensure abstinence. Consistent with this idea, the inhibition of AVPV/PVpo dopamine neurons selectively demotivates mating, whereas stimulating these neurons restores the motivation to mate after sexual satiety. We therefore conclude that the accumulation or suppression of signals from specialized dopamine neurons regulates mating behaviours across minutes and days.

Mussel-inspired poly(catecholamine) coatings from polydopamine (PDA) have been widely studied to design functional coatings for various materials. The chemical precursor of dopamine (DA), levodopa (l-DOPA, 3,4-dihydroxyphenyl-l-alanine), is known as the main element of mussel adhesive foot protein, but it is relatively hard to be constructed into a desirable coating on a given material surface under the same conditions as those for DA. Herein, we report a codeposition strategy to achieve the rapid fabrication of mussel-inspired coatings by l-DOPAwith polyethyleneimine (PEI) and to deeply understand the formation mechanism of those aggregates and coatings from l-DOPA/PEI. DFT calculations, fluorescence spectra, nuclear magnetic resonance analysis, and liquid chromatography–tandem mass spectrometry identification demonstrate that the formation of l-DOPA/PEI aggregates is effectively accelerated by PEI crosslinking with those intermediates of oxidized l-DOPA, including l-DOPAquinone and 5,6-dihydroxyindole-2-carboxylic acid as well as 5,6-dihydroxyindole, through Michael-addition and Schiff-base reactions. Therefore, we can facilely control the growth rate and the particle size of the l-DOPA/PEI aggregates in the deposition solution by adjusting the concentration of PEI. The coating formation rate of l-DOPA/PEI is four times faster than that of PDA and DA/PEI within 12 h. These l-DOPA/PEI coatings are demonstrated to display potential as structure colors, superhydrophilic surfaces, and antibacterial materials.

Fibroblast growth factor 9 (FGF9) is an autocrine/paracrine growth factor that plays critical roles in embryonic and organ developments and is involved in diverse physiological events. Loss of function of FGF9 exhibits male-to-female sex reversal in the transgenic mouse model and gain of FGF9 copy number was found in human 46, XX sex reversal patient with disorders of sex development. These results suggested that FGF9 plays a vital role in male sex development. Nevertheless, how FGF9/Fgf9 expression is regulated during testis determination remains unclear. In this study, we demonstrated that human and mouse SRY bind to -833 to -821 of human FGF9 and -1010 to -998 of mouse Fgf9, respectively, and control FGF9/Fgf9 mRNA expression. Interestingly, we showed that mouse SRY cooperates with SF1 to regulate Fgf9 expression, whereas human SRY-mediated FGF9 expression is SF1 independent. Furthermore, using an ex vivo gonadal culture system, we showed that FGF9 expression is sufficient to switch cell fate from female to male sex development in 12-16 tail somite XX mouse gonads. Taken together, our findings provide evidence to support the SRY-dependent, fate-determining role of FGF9 in male sex development.

The corrosion behavior of refinery due to severe corrosive environment was investigated in the present study, and the analysis was focused on the guiding of the corrosion into a site where is near the ground, easy to change, have low risk and so on. The corrosion parts were analyzed to study the influences of the corrosion pipe in the whole systems. Some suggestions were proposed to choose the corrosion site that can happened. By using the developed method in this study the low risk position of pipeline as a sacrificial location can be found, and then taking it as the priority corrosion place under the control of switchable subline. It is therefore to shut down for maintenance of whole pipeline, and to easily replace the corrosion parts without stop all. The serious corrosion of refining pipeline system can consequently be reduced and removed, thereby to make the long-cycle operation of refining factory be realized.

Casing radial deformation during complex fracturing process was seriously for shale gas wells in Sichuan district of China, and the average casing deformation rate in the region is of 50%. The bridge plug, perforating gun and other tools cannot successfully pass with deformed casing. Aiming at the 3-D logging morphology for deformed casing of shale gas wells, the failure modes and mechanisms were analyzed by using elasticity and theoretical mechanics. Many factors were evaluated and integrated to achieve quantitative evaluation model including geology feature, wellbore trajectory, cement property, casing material and hydrofracture process. With the aid of the self-developed unconventional oil and gas well casing simulation test equipment, the casing bearing capacity with shear load were carried out, established the relationship between shear load value and radial deformation, and further constructed the casing failure criterion with shear force. This work can provide technical support for casing design and selection in shale gas wells.

During acidizing process in a gas field, leakage of 80SS anti-sulfur tubing occurred.The main reasons for failure of the tubing have been investigated based on analysis techniques of chemical composition analysis,Optical Microscopy (OM), Scanning Electron Microscope (SEM), Energy Dispersive Spectrometer (EDS) , X-ray Diffraction (XRD) and mechanical test. The results show that composition and mechanical properties of the tubing were all in accordance with the corresponding requirements of API Spec 5CT standards. Furthermore,leakage of tubing from inner wall was caused by combined impacts of acid corrosion, H2S corrosion, low PH value, high temperature and a certain pressure. Meanwhile, Low concentration of corrosion inhibitor was also one of the factors of corrosion perforation.

In view of the external thread fracture during casing running in a well in Xinjiang Oilfield, the failure reasons of thread fracture were analyzed by combining the theory with experiment, and the casing safe service window with harsh working conditions was given. The operation of the failed casing and determined the actual working conditions of the casing threaded joints during the running process were investigated in this paper. According to the theoretical method, the boundary conditions and load conditions of the fracture casing joint in service were determined. With the aid of full-scale physical simulation test device, as well as the above boundary conditions and load conditions, the same batch casing tensile bearing characteristics were determined. Through nondestructive testing, the metallographic observation, scanning electron microscopy, spectral analysis and up-and-down test, the main controlling factors of casing thread fracture were determined. By the finite element analysis, the casing threads service state under axial tension and bending loads was established, the safety performance of threads under ideal working conditions was studied, and the fatigue mechanism of threads was revealed. Combined with the analysis results, the corresponding relationship between the casing tensile bearing characteristics and safety factor was given, which provides technical support for the safe service selection of casing body and thread under harsh conditions, saving cost and shortening the well construction period.

During heavy oil production, the performance of casing varies with temperature in the service environment. The tensile test of N80Q Steel and 80SH Steel were carried out to evaluate the mechanical properties during the service. The results indicated that the grain size of 80SH steel was relatively uniform and the grain boundary was relatively obvious compared with N80Q steel. A qualitative analysis was performance by relating the tensile properties with different temperature. The results showed that the yield strength, the tensile strength and elongation of N80Q and 80SH steels decreased with increasing temperature, but the degree of decline was limited. The observation of the tensile fracture revealed that the characteristics of the radiation zone of N80Q steel were obvious compared with 80SH steel at 20°C.

Zeolite-filled polydimethylsiloxane (PDMS) mixed matrix membranes (MMMs) were developed for pervaporation separation of n-butanol from dilute butanol–water solution. The effects of zeolite, feed butanol concentration, and temperature were studied. In general, the butanol separation factor increased with increasing the temperature, whereas the fluxes increased with the reducing membrane thickness and increasing feed butanol concentration and temperature. At 47 °C, PDMS MMMs filled with 40 wt % zeolite gave the highest separation factor of 77, which would reduce the energy consumption for butanol recovery from 1.0 wt % butanol by ∼75% to ∼10 MJ/kg butanol using a hybrid pervaporation-distillation process compared to distillation. The zeolite-filled PDMS MMM with a thickness of 10 μm would have a high butanol flux of 1000 g/m2·h at 56 °C. With a high separation factor and butanol flux, the zeolite-filled PDMS MMM would be advantageous for recovering n-butanol from dilute solution at significantly reduced energy input and cost.

A novel catalytic tautomeric transformation of a β-enaminophosphoryl and 2-aza-Cope rearrangement sequence has been successfully applied to the one-pot synthesis of β-aminophosphonates with high efficiency and good tolerance. In this tandem reaction, Bi(OTf)3exhibits unique activities and promotes both of enamine–imine tautomerism and 2-aza-Cope rearrangement.

This work presents an investigation in the numerical performance of finite element approach in the dynamic elastoplastic analysis of buried pipeline, which is subjected to random ground motion. The surrounding soil is modeled by Winkler and Pasternak type foundation, while the random ground motion is generated synthetically by generalized nonstationary Kanai–Tajimi model. The governing equation is formulated by Euler–Bernoulli beam theory and discretized by beam-pipe element. Moreover, the von Mises isotropic hardening model is employed for material behavior modeling. The Hilber–Hughes–Taylor (HHT) method and the Newton–Raphson method are adopted as the time incremental iterative algorithm to solve the global equilibrium equation. Several applications are carried out to investigate the numerical performance of the present numerical model in dealing with the dynamic elastoplastic analysis of buried pipe. The norm L 2 of stress and displacement error are determined for different time intervals and the factors that contribute to the error reduction are investigated in present work. [ABSTRACT FROM AUTHOR]

With triphenylphosphine oxide serving as both the directing group and the reagent, we have developed a Cp*Ir(III)-catalyzed direct C–H functionalization of triphenylphosphine oxide with 3-diazooxindoles to afford a range of 3-(2-(diphenylphosphoryl)phenyl)indolin-2-one derivatives in moderate to excellent yields. The title products are potentially important building blocks for organic synthesis through various chemical transformations. This protocol is simple and efficient and offers high atom economy with only N2as the byproduct.

The palladium–N-heterocyclic carbene (NHC)-catalyzed allylic alkylation of various pronucleophiles with alkynes has been accomplished under mild conditions. The protocol exhibits broad functional group compatibility and high atom economy. Moreover, the catalytic process avoids the use of external oxidants and acid as additives.

In this work, an efficient palladium-catalyzed Heck-type reaction was successfully used to synthesize a wide range of monoaryl- or diaryl-substituted P-ligands with excellent yields and diastereoselectivity (up to 98% yield, dr >20:1). The preliminary mechanistic studies demonstrated that it possibly underwent a cationic Heck reaction that was assisted by silver salt, and it revealed the significant role of P(O)Ar2for excellent yields and diastereoselectivity.

We demonstrate efficient pulse compression of a 13.4 MHz, 534 fs, 123 W, Yb:YAG thin-disk oscillator down to 27 fs at 98 W average power, resulting in a record-high 166 MW peak power from an amplifier-free oscillator-driven setup. Our compressor is based on two stages: one multipass cell allowing us to reduce the pulse duration to sub-90 fs and, subsequently, a multiple-plate compressor, allowing us to reach 27 fs. The overall average power compression efficiency is 80%, and the beam has excellent beam quality and homogeneity. In addition, we demonstrate further spectral broadening that supports a transform limit of 5 fs in a second multiple-plate stage, demonstrating the potential for reaching a 100 W class, amplifier-free, few-cycle source in the near future. The performance of this unique source is very promising for applications previously restricted to amplified sources, such as efficient generation of extreme ultraviolet light at high repetition rate, and the generation of high-power broadband THz radiation.

Taiwan Pediatric Oncology Group (TPOG)-ALL-2013 protocol (TPOG-2013), modifying from St. Jude Total Therapy XV Study and Total Therapy XVI Study, was launched since January 2013. This is the first nationwide minimal residual disease (MRD)-directed protocol for treatment of childhood acute lymphoblastic leukemia (ALL) in Taiwan. According to TPOG-2013, two MRD measurements were scheduled on days 15-19 of induction (MRD1 time point, TP1) and days 35-42, end of induction (MRD2 time point, TP2) to make the definitive risk stratification to guide subsequent therapy.

Cardiovascular disease (CVD) is an emerging cause of morbidity and mortality among HIV-positive patients receiving successful combination antiretroviral therapy, but their CVD risk has been rarely investigated in Asia–Pacific region. We aimed to assess the CVD risk of HIV-positive Taiwanese outpatients.

In this paper, 6013 aluminum alloy with the thickness of 2.5mm was overlap welded by fiber laser. The microstructure, mechanical properties and fracture morphology of the joint was tested and observed by Optical Microscope, material testing machines and Scanning Electron Microscope, thus the failure and fracture mechanism of the welded joint are analyzed. The results showed that good shape of weld was achieved under the optimal welding parameters. Equiaxial as-cast microstructures exist in the welding center and the columnar grains are formed near the fusion line in the WZ. The hardness of weld zone is the lowest in the joint, which is about 72 HV, about 57% of that of BM. The tensile shear strength of the joint is 96Mpa, about 25% of tensile strength of BM. The fracture is happened in WZ and the brittle fracture mode is dominated with shear dimples and shear planes.