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Efficient and robust bifunctional non-precious metal electrocatalysts, used for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), are crucial to develop water splitting commercial applications. Herein, a bottom-up self-assembly strategy is proposed to construct ternary electrocatalysts of nitrogen-doped graphene-like carbon layers encapsulated Mo x C (x = 1, 2) and Ni 3 Fe alloy nanoparticles (Mo x C/Ni 3 Fe@GL) for efficient water electrolysis. The optimized sample (0.27Mo x C/Ni 1.5 Fe@GL, 0.27 represent the mass of ammonium molybdate in the precursor) requires overpotentials (η 10) of 88 and 150, 265 mV in 0.5 M H 2 SO 4 for HER and 1.0 M KOH for HER and OER, respectively. Furthermore, as a bifunctional electrocatalyst in a two-electrode cell, 0.27Mo x C/Ni 1.5 Fe@GL requires only 1.523 V at 10 mA cm−2, which surpasses the noble metal RuO 2 (+)||Pt/C(−) in 1.0 M KOH electrolyte, and shows excellent stability by working at 20 mA cm−2 long as 150 h. The superior electrocatalytic performance can mainly originate from Mo x C and Ni 3 Fe alloys synergistically effected results. The partial doping of Ni or Fe atoms into Mo 2 C optimizes the electronic structure, making the intrinsic activity enhanced. On the other hand, the incorporation of Mo x C heterophases effectively inhibits the Ni 3 Fe nanoparticles agglomeration, benefitting to expose more active sites. Moreover, the protection of encapsulated thin N-doped graphene-like carbon layers for the nanoparticles against corrosion, guarantees the long-time durability. This work provides a potential general bottom-up self-assembly approach to construct high-performance electrocatalysts with multiphase heterostructures with enriched abundant active sites and enhanced intrinsic activity for energy coversion fields. Ternary Mo x C (x = 1, 2) and Ni 3 Fe alloy nanoparticles encapsulated in N-doped graphene-like carbon layers (Mo x C/Ni 3 Fe@GL) are synthesized by a bottom-up self-assembly method. Mo x C/Ni 3 Fe@GL exhibits efficient and stable electrocatalytic water splitting performance. [Display omitted] • Mo x C/Ni 3 Fe@GL was prepared by a facile bottom-up self-assembly strategy. • The synergistic effect of Mo x C and Ni 3 Fe alloy enhanced the intrinsic activity. • N-doped graphene-like thin carbon layers improved the conductivity and stability. • Water splitting required only 1.523 V to reach 10 mA cm−2 and stably for 150 h. [ABSTRACT FROM AUTHOR]

Nowadays, the evaluation of students' learning effect in colleges and universities mainly rely on manual management and supervision, which is inefficient and inaccurate. What's worse, it completely depends on the subjective judgment of the supervisors, many potential teaching quality data could be ignored. Using an unsupervised classroom monitoring system based on deep learning can master the learner's learning result. This paper mainly researched a learner's behavior evaluation method based on deep learning. Firstly, MTCNN is being used to detected learner's facial feature in order to confirm their identification. Then, collected the data set in learning environment and a Mosaic data enhancement had been done. Later, an improved method, is proposed. Identifying the students' actions of playing the mobile phone, moving to classroom, eating, reading, writing, this method has more advantages on classroom behavior detecting. In addition, by building a quantitative evaluation method–CFIndex (class focus index), the time of students' behaviors in classroom has been calculated. Therefore, CFIndex evaluation method can well reflect the real performance of students in the classroom. In this paper, compared with Fast R-CNN and classical algorithm on the same data set, the proposed method has better performance in classroom behavior detection, and it can better reflect the students' real actions in the classroom, it has certain meaning of theoretical guidance. [ABSTRACT FROM AUTHOR]

Background: To summarize the safety and effectiveness of high flow extracranial to intracranial saphenous vein bypass grafting in the treatment of complex intracranial aneurysms.Methods: The data of complex intracranial aneurysms patients for high flow extracranial to intracranial saphenous vein bypass grafting from January 2008 to January 2020 were retrospectively collected and analyzed. Eighty-two patients (31 men and 51 women) with 89 aneurysms underwent 82 saphenous vein bypass grafts followed by immediate parent vessel occlusion. The aneurysm was located at the internal carotid artery, middle cerebral artery, and basilar artery in 75, 11, and 3 cases, respectively.Results: The patency rate of bypass grafting was 100, 100, 96.3 and 92.4% on intraoperation, on the first postoperative day, at discharge and 6 months follow-up, respectively. At discharge and 6 months follow-up, 3 and 6 patients had graft occlusions. The main postoperative complications were transient hemiparesis and hemianopsia. 3 patients died due to bypass complications and poor physical condition.Conclusions: High flow extracranial to intracranial saphenous vein bypass grafting is safe and effective in the treatment of complex intracranial aneurysms and the saphenous vein can meet the requirements of brain blood supply. A high rate of graft patency and adequate cerebral blood flow can be achieved.Highlights: A single-centre long-term retrospective study was conducted to assess the safety and effectiveness of high flow EC-IC saphenous vein bypass grafting in the treatment of complex intracranial aneurysms. The data of 82 patients from January 2008 to January 2020 were retrospectively collected and analysed. We found the patency rate of bypass grafting was 100, 100, 96.3 and 92.4% on intraoperation, on the first postoperative day, at discharge and 6 months follow-up, respectively. At discharge and 6 months follow-up, 3 and 6 patients had graft occlusions. Finally, we conclude that high flow extracranial to intracranial saphenous vein bypass grafting is safe and effective in the treatment of complex intracranial aneurysms and the selected blood supply vessels can meet the requirements of blood supply. As far as we know, this study is one of the maximum number of cases in the treatment of complex intracranial aneurysms with saphenous vein bypass. [ABSTRACT FROM AUTHOR]

This study proposes a model predictive control (MPC) method with a fixed weighting factor for three‐phase four‐switch inverter‐fed permanent magnet synchronous motor drives to suppress the capacitor voltage offset. The prediction model of the capacitor voltage difference is obtained based on the relationship between capacitor voltage and phase current. Then by analysing the relationship between basic voltage vector, electromagnetic torque and flux amplitude, the control of electromagnetic torque and flux in the model predictive torque control is transformed into the control of the voltage vector. The dimension of the capacitor voltage difference is the same as that of the voltage vector, hence the cost function with the fixed weighting factor is defined with the consideration of the capacitor voltage offset suppression. The effectiveness of the proposed MPC method is validated by the simulation and experiment. [ABSTRACT FROM AUTHOR]

Background: Primary pineal malignant melanoma (PPMM) is a rare entity of primary central nervous system melanomas, with only 26 cases reported in the literature to date. Case presentation: We report the case of a 65-year-old male with a PPMM who has prolonged survival of more than 104 weeks after combined microsurgical and endoscopic total resection. This is the first report: combined microscope and endoscopy total resection; PPMM in China; PPMM with total resection alone. Conclusion: Combined microscope and endoscopy total resection is beneficial to prolong the survival of patients. But the best approach to treatment needs verification from more clinical cases in future. [ABSTRACT FROM AUTHOR]

This article proposes a model-based strategy with robust parameter mismatch for online high resistance connection (HRC) diagnosis and localization in surface-mounted permanent magnet synchronous machine (PMSM) drive system. The mathematical mode of the PMSM with the HRC is established in the abc stationary frame and dq rotating frame. Based on the model, the voltage distortion estimator is applied to estimate the voltage distortions caused by the HRC. According to the voltage distortions, a new fault characteristic signal is defined and is analyzed under different fault conditions. Based on the defined signal, the fault indicators being insensitive to the parameter mismatch are defined to diagnose the fault and locate the faulty phases. By the proposed method, not only the HRC can be detected, but also the fault severity can be assessed and the faulty phases can be located, where no additional equipment or measurement devices are needed. Both the simulation and experimental results verify that the proposed method can effectively achieve online HRC diagnosis and location in the PMSM drive system. [ABSTRACT FROM AUTHOR]

Introduction: Thalassemia traits and iron deficiency anemia are the most common types of hypochromic microcytic anemia with similar clinical and laboratory features. It is vital to establish a new screening model based on HbA2 levels and red cell indices for the differentiation of TT from IDA in hypochromic microcytic anemia cases. Method: The data comprised of the red blood cell indices and HbA2 prenatal diagnostic test results of 810 individuals who were identified to conform to the following criteria: MCV < 80 fl or MCH < 26 pg. We launched a new model consisting mainly of significative red cell indices and HbA2 levels, as well as proposing cutoff values by using decision trees and logistic regression analyses. Next, we evaluated our new method by comparing the sensitivity, specificity, positive, and negative predictive values with those of the previous formulas. Results: We put forward a new model and compared it with 5 efficient formulas. The new model exhibited the highest accuracy (0.918), with its sensitivity and specificity calculated as 0.917 and 0.921, respectively. Our new model's Youden index was 0.838, which is higher than the other formulas' Youden indices. Conclusions: The new screening model, based on HbA2 levels and red cell indices, is suitable for the screening of thalassemia patients in the hypochromic microcytic anemia group and has the best efficiency in distinguishing TT and IDA. [ABSTRACT FROM AUTHOR]

• First and largest series report on ICSH surgical treatment. • We compared the surgical data and patient outcomes at different stages. • We found EATD is a more effective method for ICSH. Isolated chronic subdural hematoma (ICSH), as a special rare species, has great controversy over its treatment. A retrospective analysis was performed to compare craniotomy with endoscopic-assisted trepanation drainage (EATD) of ICSH. The data of ICSH patients for craniotomy or EATD from January 2011 to April 2019 were retrospectively collected and analysed. Of 106 patients, 49 and 57 patients received craniotomy and EATD treatment respectively. Recurrence rate, morbidity and mortality rate were the main outcome. There was no recurrence in both groups. The morbidity rate of the EATD group (2/57, 3.5%) was significantly lower than that of the craniotomy group (17/49, 34.7%, p = 0.0033). There was no death in the EATD group, but 3 cases died of operative produce in the craniotomy group. The average operation time of the craniotomy group (95.3min) was significantly longer than that of the EATD group (66.5min, P = 0.0032). Craniotomy group had more intraoperative blood loss (213.2ml) than EATD group (34.5ml, P = 0.0044). EATD patients had shorter hospital stay and recovered faster. Compared with craniotomy, EATD is a more effective and safer method for the treatment of ICSH. [ABSTRACT FROM AUTHOR]

Interturn fault (ITF) is a common fault for permanent magnet synchronous machine (PMSM). If the ITF is not detected in time, its propagation may result in the secondary damage, even the damage to the whole electrical machine. Recently, model predictive control (MPC) has been widely studied for the PMSM drive system because of its simple structure and excellent dynamic performance. However, the previous ITF diagnosis methods are mainly focused on vector control and direct toque control systems, and few research works are specifically focused on ITF diagnosis for the model-predictive-controlled-PMSM. Hence, to fill this gap and improve the reliability of the model-predictive-controlled-PMSM, this article first proposes an ITF diagnosis method for the model-predictive-controlled-PMSM, taking into account the characteristics of the MPC system. In this method, wavelet transform is applied to extract the fault feature from the cost function existing in the MPC system, and the ITF is diagnosed by monitoring the normalized energy-related feature vector calculated from the wavelet transform coefficients. Additionally, to further show the performance of the proposed method, the popular diagnosis methods based on the stator current and zero sequence voltage component are studied for the comparative analysis. Both the simulation and experimental results verify the effectiveness of the proposed fault diagnosis method. [ABSTRACT FROM AUTHOR]

• To summarize the application of PEEK in cranioplasty. • The comparison of PEEK with several commonly used materials in previous articles is reviewed. • Currently the most complete data review article. • The surface of PEEK and PEEK composites as implant materials were reviewed. • Application prospect of PEEK in clinical cranioplasty. Cranioplasty is a challenge to neurosurgeons, especially considering protection of intracranial contents. In recent years, material choice for cranioplasty is still controversial, which brings complexity to this seemingly straightforward procedure. PEEK, a tough, rigid, biocompatible material, has been used more recently in cranioplasty to provide better protection. The aim of this review is to summarize the outcome of research conducted on the material for cranioplasty applications. We also reviewed the comparison of PEEK with several common materials in previous articles. This is also the most complete data review article at present. In addition, the combination of nano-materials and PEEK is also a hotspot of research, so we have made a careful review of this aspect. We also summarized our own experience, telling about the future prospects of PEEK in the field of clinical cranioplasty should be highlighted. Improving the bioactivity, porosity, thinning, biocompatibility, antibacterial ability, integration and cost reduction of PEEK implants without affecting their mechanical properties is a major challenge. [ABSTRACT FROM AUTHOR]

Abstract We present here a straightforward synthesis of highly efficient bifunctional OER/ORR catalysts through a facile laser-induced graphene (LIG) process to produce Co 3 O 4 /LIG. The Co 3 O 4 /LIG showed OER and ORR activity comparable to noble metal-based catalysts in alkaline electrolyte. Furthermore, the Co 3 O 4 /LIG exhibited promising performance in Zn-air and Li-O 2 batteries. The rechargeable Zn-air battery has an open-circuit potential of 1.46 V and a high power density of 84.2 mW/cm2 at 100 mA/cm2. The Li-O 2 battery with the Co 3 O 4 /LIG cathode exhibits low overpotentials in both charge and discharge processes and excellent cycling stability up to 242 cycles. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) MoS 2 has recently emerged as an efficient hydrogen evolution reaction (HER) catalyst due to its unique atomic layered structure and stability in harsh acidic environment. However, the high electrochemical performance of MoS 2 is still limited to edges of its 2D layers. Here, we report the synthesis of highly porous MoS 2 films exhibiting a large density of edge sites by using a direct sputter deposition method. Interestingly, the as-deposited MoS 2 films resulted into a 3R phase with nano porous structure which is attributed to the lattice relaxation and high energy of sputtered ions. The as-synthesized porous MoS 2 nanostructures demonstrate an excellent electrocatalytic performance with a low HER onset potential of ∼0.2 V, long-term cycling stability, and a low Tafel slope in the range of ∼80–90 mV/decade at a high cathodic current density. [ABSTRACT FROM AUTHOR]

Objective To complete a retrospective comparison of endoscope-assisted burr-hole craniostomy (EBHC) and ordinary burr-hole craniostomy (OBHC) in the treatment of septated chronic subdural hematoma (SCSH). Methods A retrospective case note review comparing EBHC and OBHC of SCSH was therefore performed. Data of patients with a SCSH for EBHC or OBHC during the period from January 2011 to December 2016 were retrospectively collected and analysed. Of 73 patients, 42 underwent EBHC and 31 patients were treated by OBHC. The primary outcome measure was recurrence rate and secondary outcome measures were clinical outcome at first postoperative day, discharge and 6 months, the length of hospital stay for neurosurgery, the operative time, and the placement time of drainage tube. Result The rate of recurrence was significantly lower in the EBHC (0/42 0%) than in the OBHC (8/31, 25.8%) group ( p  = .0030). The rate of morbidity was significantly lower in the EBHC (2/42, 4.8%) than in the OBHC (11/31, 35.5%) group ( p  = .0121). At 30 days, mortality did not differ between groups. Significantly more patients treated with EBHC were alive at 6 months than were those with OBHC. No patient died as a consequence of the operative procedure in the both groups. A discharge GCS of 15 was recorded in more participants with EBHC than in those with OBHC. Gross neurological deficit was significantly less frequent in those with EBHC than in those with OBHC at first postoperative day and discharge, but did not differ at 6 month follow-up. The mean placement time of drainage tube was significantly less in those with EBHC (27.2 h) than in those with OBHC (52.0 h, p  = .0055). The mean length of hospital stay for neurosurgery was 4 days in the EBHC group, while it was 5 days in the OBHC group ( p  = .0015). The mean hematoma reduction rate was significantly higher in those with EBHC than in those with OBHC at first postoperative day (85.3% vs 72.5%, p  = .0037) and discharge (90.3% vs 85.1%, p  = .0127). Conclusion Comparing two minimally invasive procedure protocols for treatment of SCSH, EBHC is a safe and effective surgical technique. It significantly surpasses the results obtained in OBHC in lowering recurrence rate, morbidity rate, placement time of drainage tube, and length of hospital stay for neurosurgery. We recommend EBHC technique to be widely used in the treatment of SCSH, even common chronic subdural hematoma (CSH), subacute and acute subdural hematomas, acute epidural hematomas and empyemas to avoid large craniotomies, particularly in elderly patients, so that patients can receive the best treatment on the basis of minimal trauma. [ABSTRACT FROM AUTHOR]

Background Microelectrode recording (MER) and intraoperative magnetic resonance imaging (iMRI) have been used in deep brain stimulation surgery for Parkinson disease (PD), but comparative methodology is lacking. Therefore, we compared the 1-year follow-up outcomes of MER-guided and iMRI-guided subthalamic nucleus (STN) deep brain stimulation (DBS) surgery in PD patients. Methods We conducted a review comparing PD patients who underwent MER-guided (n = 76, group A) and iMRI-guided STN DBS surgery (n = 61, group B) in our institution. Pre- and postoperative assessments included Unified Parkinson's Disease Rating Scale-III (UPDRS-III) score, Parkinson's Disease Questionnaire (PDQ-39), Mini-Mental State Examination (MMSE), levodopa equivalent daily doses (LEDDs), and magnetic resonance images. Results The mean magnitudes of electrode discrepancy were x = 1.1 ± 0.2 mm, y = 1.3 ± 0.3 mm, and z = 2.1 ± 0.5 mm in group A and x = 1.3 ± 0.4 mm, y = 1.2 ± 0.2 mm, and z = 2.5 ± 0.7 mm in group B. Significant differences were not found between 2 groups for x , y , or z ( P = 0.34, P = 0.26, and P = 0.41, respectively). At 1 year, when levodopa was withdrawn for 12 hours, the UPDRS-III score improved by 66.3% ± 13.5% in group A and 64.8% ± 12.7% in group B ( P = 0.24); the PDQ-39 summary index score improved by 49.7% ± 14.3% in group A and 44.1% ± 12.7% in group B ( P = 0.16); the MMSE score improved by 4.2% ± 2.1% in group A and 11.1% ± 3.2% in group B ( P = 0.43); and LEDDs decreased by 48.7% ± 10.1% in group A and 56.9% ± 12.0% in group B ( P = 0.32). Conclusions MER and iMRI both are effective ways to ensure adequate electrode placement in DBS surgery, but there is no superiority between both techniques, at least in terms of 1-year follow-up outcomes. [ABSTRACT FROM AUTHOR]

The thyroid hormone receptor α1 (TRα1) is a nuclear receptor for thyroid hormone that shuttles rapidly between the nucleus and cytoplasm. Our prior studies showed that nuclear import of TRα1 is directed by two nuclear localization signals, one in the N-terminal A/B domain and the other in the hinge domain. Here, we showed using in vitro nuclear import assays that TRα1 nuclear localization is temperature and energy-dependent and can be reconstituted by the addition of cytosol. In HeLa cells expressing green fluorescent protein (GFP)-tagged TRα1, knockdown of importin 7, importin β1 and importin α1 by RNA interference, or treatment with an importin β1-specific inhibitor, significantly reduced nuclear localization of TRα1, while knockdown of other importins had no effect. Coimmunoprecipitation assays confirmed that TRα1 interacts with importin 7, as well as importin β1 and the adapter importin α1, suggesting that TRα1 trafficking into the nucleus is mediated by two distinct pathways. [ABSTRACT FROM AUTHOR]

A novel organic fluorophor with high solid state luminescent efficiency based on 1,4-bis(2,2-di(pyridin-2-yl)vinyl)benzene (BDP2VB) was designed and synthesized. It emits faintly in solution, but becomes a strong emitter in the aggregate state, demonstrating its aggregation induced emission (AIE) property. According to the crystal structure analysis, J-type aggregation was formed in the packing mode of the molecule, which was demonstrated to be beneficial to gain high fluorescent quantum efficiency in solid state. Additionally, the emission color of BDP2VB can change dramatically in solid state as well as in solution by the protonation stimuli. [ABSTRACT FROM AUTHOR]

[Display omitted] • A batch production route is established for large-area, uniform SnO 2 ETLs film by chemical bath deposition. • The mercaptosuccinic acid is applied on the SnO 2 surface modification for energy band alignment and defects passivation. • A PCE variance (V a) with the as-made SnO 2 is 0.073, comparing to that of control sample of V a at 2.833. • A high efficiency of 22.54% was obtained for the FA-based perovskite device. Chemical bath deposited tin oxide film (CBD SnO 2) has been demonstrated as an amazing electron transporting layer for high photoconversion efficiency (PCE) hybrid perovskite solar cells (PSCs) over 25 %. The current CBD process is normally studied for small area devices. A rapid batch production of large-area CBD SnO 2 film with high and uniform performance is essential for potential upscaling of perovskite solar module. Herein, we carried out a modified batch CBD process, a double chemical bath deposition (DC), for batch fabrication of large-area (400 cm2) SnO 2 films and realized a homogenized PCE with a variance (V a) of 0.127, comparing to that of control sample of V a at 2.833. We further introduced mercaptosuccinic acid (MSA) at the interface of SnO 2 /perovskite for convenient energy band alignment and defects passivation, which significantly improved the PCE , stability and homogeneity of the devices. As a result, the mix-cation planar PSCs reaches 21.24% with further reduced V a of 0.073. A high efficiency of 22.54% was obtained for the narrow band gap FA-based perovskite device. These results suggest high potential of this modified CBD route for large area and high efficiency perovskite module preparation. [ABSTRACT FROM AUTHOR]

Insights into the origin of the fluorescence responsive to protonation–deprotonation stimuli were provided through the study on the crystals of a new stimuli-responsive molecule BP3VA. And the transformation between microcrystals demonstrated the varying emissions of the BP3VA powder. [ABSTRACT FROM AUTHOR]

Cerebral hyperperfusion syndrome (CHS) after bypass surgery is known as a complication of moyamoya disease (MMD). However, the incidence of CHS has not been accurately reported, and there is no consensus on related risk factors. To evaluate the incidence and characteristics of CHS in patients with MMD after revascularization surgery via meta-analysis. Relevant cohort studies were retrieved through a literature search of PubMed, Embase, and Ovid until December 1, 2018. Eligible studies were identified per search criteria. A systematic review and meta-analysis were used to assess the CHS total incidence, incidence in pediatric patients with MMD and adult patients with MMD, incidence for direct and combined bypass surgery, progress rate, and proportion of each symptom (including transient neurologic deficits [TNDs], hemorrhage, and seizure). A total of 27 cohort studies with 2225 patients were included in this meta-analysis. The weighted proportions per random-effects model were 16.5% (range, 11.3%–22.3%) for CHS total incidence, 3.8% (range, 0.3%–9.6%) for pediatric patients with MMD, 19.9% (range, 11.7%–29.4%) for adult patients with MMD, 15.4% (range, 5.4%–28.8%) for direct bypass surgery, and 15.2% (range, 8.4%–23.2%) for combined bypass surgery. Progress rate was 39.5% (range, 28.7%–50.8%). The most common CHS-related symptom was TNDs (70.2%; range, 56.3%–82.7%), followed by hemorrhage (15.0%; range, 5.5%–26.9%) and seizure (5.3%; range, 0.6%–12.9%). CHS is a common complication after revascularization surgery in MMD. It is more frequently seen in adult patients. The most common CHS-related symptom was TNDs, followed by hemorrhage and seizure. [ABSTRACT FROM AUTHOR]

Recently, the pivotal to electrocatalytic water splitting is developing efficient and earth-abundant electrocatalysts to accelerate the sluggish kinetics of hydrogen and oxygen evolution reactions (HER and OER). In this work, (NH 4) 2 MoS 4 derived from polyoxometalates ((NH 4) 6 Mo 7 O 24 ·4H 2 O) were immobilized onto the ion exchange resin D314, and highly dispersed Co-molybdenum disulfide (Co–MoS 2 @NG-4) on nitrogen-doped graphene catalyst was prepared. The optimized Co–MoS 2 @NG-4 shows excellent electrocatalytic performance for HER and OER. Specifically, the low overpotentials of 202 and 352 mV are required to drive the current density of 10 mA cm−2 with the small Tafel slope of 77.30 and 153.50 mV dec−1 for HER and OER, respectively. The Co–MoS 2 @NG-4 demonstrates excellent stability, maintaining a robust operation for 5000 cyclic tests with no detectable stability decay. Porous structure endows Co–MoS 2 @NG-4 with more active centers, increasing its specific surface area and ultimately improving its catalytic performance. [Display omitted] • Synthesized Co–MoS 2 @NG-4 catalyst using ion-exchange and thermal reduction methods. • The porous structure and heteroatom doping improve the electrocatalytic activity. • The Co–MoS 2 @NG-4 exhibits excellent electrochemical activity for both HER and OER. • The Co–MoS 2 @NG-4 exhibits exceptional stability. [ABSTRACT FROM AUTHOR]

Open-phase fault (OPF) in the permanent magnet synchronous machine (PMSM) drive system is one of the most prevalent failures due to the resulting large electromagnetic torque ripples and serious mechanical vibration. To improve the reliability of the PMSM drive system, several OPF diagnosis methods were studied and were mainly focused on vector control system. Recently, model predictive control (MPC) has been emerging as a popular control method for the PMSM drive system owing to its simple structure and excellent dynamic performance. However, so far, there are no special OPF diagnosis methods for the model predictive controlled PMSM drive system. Hence, this article first proposes a cost function-based OPF diagnosis method for the model predictive controlled PMSM drive system, considering the characteristics of MPC system. The dc component and second harmonic component in the cost function are used for the OPF diagnosis, and the initial phase angle differences are defined to locate the faulty phase. The experimental results show that, by the proposed fault diagnosis method, not only the OPF can be rapidly detected, but also the faulty phase can be effectively located. Moreover, the proposed method can be implemented simply and is robust against the operating point and parameter variations of the PMSM drive system. This article proposes an OPF diagnosis method for the model predictive controlled PMSM drive system based on cost function, taking into account the characteristics of the MPCC system. The experimental results verify the effectiveness of the proposed method. From the theoretical analysis and experimental results, the following works and conclusion are drawn. [ABSTRACT FROM AUTHOR]

Background: Previous studies have shown that vinorelbine/capecitabine (NX) and docetaxel/capecitabine (TX) chemotherapy has a certain effect in advanced breast cancer. However, there are few clinical studies directly comparing TX and NX regimen chemotherapy, especially in patients with advanced breast cancer previously treated with anthracycline and taxane. The purpose of this Phase II study was to compare survival and side effects between patients with anthracycline- and taxane-resistant advanced breast cancer treated with NX and those treated with TX chemotherapy.Patients and Methods: From February 2012 to March 2014, a total number of 97 patients were randomly assigned to NX (n = 55) or TX (n = 42). Baseline characteristics were relatively well-balanced in the two treatment arms. The clinical trial registration number (clincaltrials.gov) is NCT01635465.Results: After a median follow-up of 46.0 months, there was no significant difference between the NX and TX arms in objective response rate (17.9% vs. 21.1%; P = 0.686) and progression-free survival (6 months vs. 7 months; P = 0.560). The overall survival period of the TX arm was longer than that of the NX arm (32 months vs. 27 months) but without statistical significance. Both regimens were well-tolerated. The main toxicities were neutropenia, leukopenia, and anemia. In the TX arm, hand-foot syndrome occurred more frequently than in the NX arm (P < 0.01), but frequencies of other minor adverse effects were similar between the two arms.Conclusion: NX and TX regimens are both alternative treatments for patients with anthracycline- and taxane-resistant advanced breast cancer, but the safety profile was more favorable and manageable with the NX regimen.Trial Registrations: ClinicalTrials.gov NCT01635465. Registered 09 July 2012. [ABSTRACT FROM AUTHOR]

Electrocatalysts with a high oxygen evolution reaction (OER) activity are very important for electrochemical water oxidation, but they are also challenging. In this study, N-doped graphene-like supported highly dispersed bimetallic NiCoP NPs as an efficient electrocatalyst for water oxidation were prepared by using cation exchange resin as a carbon source and by loading cobalt and nickel on D001 by a high-temperature calcination method. The designed electrocatalyst with bimetallic phosphide as the active center shows excellent OER catalytic performance, with an overpotential of 324 mV at 10 mA cm−2 and a corresponding Tafel slope of 97.28 mV dec−1. The increase in NiCoP-3@GL activity may be due to the increase in surface area (933.49 m2 g−1) caused by the irregular morphology, rich interface contact, and porous structure. In addition, the strong combination of NiCoP and GL improves the structural stability and durability of the electrocatalyst. After 5000 cyclic voltammetry tests, the performance of the catalyst decreased by 16.9 %. This work provides a new idea for designing efficient bimetallic phosphide electrocatalysts. [ABSTRACT FROM AUTHOR]

Objective To evaluate the diagnostic value and safety of stereotactic biopsy in acquired immune deficiency syndrome (AIDS) patients with intracranial lesions via meta-analysis. Methods Relevant cohort studies were identified through a literature search in PubMed, Embase, and Ovid from 1985 to October 1, 2016. Appropriate studies were identified per search criteria. Systematic review and meta-analysis were used to assess the diagnostic success rate, changed management rate, clinical improvement rate, mortality rate, morbidity rate, hemorrhage rate, hemorrhage in morbidity rate, and final histologic diagnosis results. Study-specific outcomes were combined per a random effects model. Outcomes were compared between the pre-highly active antiretroviral therapy (HAART) and post-HAART groups. Correlations between outcomes were assessed via meta-regression analysis. Results A total of 19 cohort studies with 820 patients were included in this meta-analysis. The weighted proportions per the random effects model were 92.2% (95% confidence interval [CI; 89.3%–94.5%]) for diagnostic success rate, 5.1% (95% CI [2.5%–8.3%]) for morbidity, and 0.7% (95% CI [0%–1.9%]) for mortality. The most common procedure-related morbidity was hemorrhage at 3.3% (95% CI [1.1%–6.3%]). Hemorrhage in morbidity was 78.0% (95% CI [51.4%–97.4%]). Management changed and clinical improvement were 60.4% (95% CI [49.4%–71.0%]) and 34.0% (95% CI [22.2%–46.8%]), respectively. The 4 most common diagnoses were primary central nervous system lymphoma (27.8%; 95% CI [20.2%–36.1%]), progressive multifocal leukoencephalopathy (PML) (21.0%; 95% CI [14.3%–28.4%]), toxoplasma encephalitis (TE) (20.3%; 95% CI [14.3%–27.0%]), and human immunodeficiency virus (HIV) encephalitis (4.1%; 95% CI [1.4%–7.6%]). Multiple diagnoses rate was 1.2% (95% CI [0.0%–3.6%]). HIV encephalitis rate was significantly higher in the post-HAART group than the pre-HAART group (17.9% vs. 3.2%, respectively; P = 0.0024). Conclusions Stereotactic biopsy is a safe and effective way of diagnosing intracranial lesions in patients with AIDS. It is helpful for the differential diagnosis and for choosing a suitable therapy. The 4 most common intracranial lesions in patients with AIDS are lymphoma, PML, TE, and HIV encephalitis. [ABSTRACT FROM AUTHOR]

Objective To investigate the clinical benefits of emergent single burr hole evacuation technology in traumatic acute subdural hematoma (ASDH) with cerebral herniation cases. Methods We conducted a review comparing patients with ASDH with cerebral herniation who underwent single burr hole evacuation followed by decompressive craniectomy and intracranial hematoma removal surgery (n = 45, group A) and those who underwent decompressive craniectomy and intracranial hematoma removal surgery after rapid infusion of mannitol 250 mL (n = 53, group B) in our institution. Pre- and postoperative assessments included Glasgow Coma Scale (GCS), Glasgow Outcome Scale (GOS), activities of daily living (ADLs), and common complication incidences. Results At 1 and 6 months after operation, the median GCS score of group A was significantly higher than group B (P = 0.04 and P = 0.03, respectively). After 6 months, the GOS score and ADLs between the 2 groups had significant differences (P < 0.05). There were no differences between the 2 groups in the common complication incidences. Conclusions Emergent single burr hole evacuation in combination with decompressive craniectomy surgery is a useful treatment for ASDH with cerebral herniation, which can achieve reduction of intracranial pressure as soon as possible and improve the prognosis. Highlights • No reports have described the efficacy of emergent single burr hole evacuation for ASDH with cerebral herniation. • We studied a series of patients with ASDH with cerebral herniation. • Single burr hole evacuation is an effective and safe treatment for traumatic ASDH with cerebral herniation. • It can reduce intracranial pressure rapidly and relieve cerebral hernia. [ABSTRACT FROM AUTHOR]

Background: Nance–Horan syndrome (NHS) is a rare and often overlooked X‐linked dominant disorder characterized by dense congenital cataracts, dental abnormalities, and mental retardation. The majority of NHS variations include frameshift mutations, nonsense mutations, microdeletions, and insertions. Methods: Copy number variation sequencing was performed to determine the microdeletion. The expression of NHS was detected by RT‐PCR. Four family members were tested for X chromosome inactivation. Results: In this study, all members were examined for systemic examinations and genetic testing of four members and two affected subjects are observed. We identified a heterozygous microdeletion of −0.52 Mb at Xp22.13 in a female proband presenting NHS phenotypically. The microdeletion contains the REPS2 and NHS genes and was inherited from a phenotypically normal mother. Of interest, the expression NHS of proband was reduced and the skewed X chromosome inactivation rate reached more than 85% compared with her mother and the control. It was concluded that the haploinsufficiency of the NHS gene may account for the majority of clinical symptoms in the affected subjects. The variability among female carriers presumably results from nonrandom X chromosome inactivation. Conclusion: Our findings broaden the spectrum of NHS mutations and provide molecular insight into NHS clinical prenatal genetic diagnosis. [ABSTRACT FROM AUTHOR]

The crop leaf color is tightly connected with its meteorological environment. Color gradation skewness-distribution (CGSD) parameters can describe the information of leaf color more accurately, systematically, and comprehensively from five dimensions. We took photographs of pepper growing in the greenhouse at a fixed time every day and observed the meteorological factors. The results showed that the CGSD parameters were significantly correlated with meteorological factors, especially with the accumulated temperature, which showed the strongest correlation. Since the relationship between canopy leaf color and accumulated temperature is nonlinear, the piecewise inversion models were constructed by taking the stationary point of the high-order response model of Gskewness to accumulated temperature as the point of demarcation. The rate of outliers had decreased by 57.72%; moreover, the overall inversion accuracy had increased by 3.31% compared with the linear model directly constructed by the stepwise regression. It was observed that the pepper in the greenhouse had a different response to the same meteorological environmental stimulus before and after the stationary point. This study will provide a new method for constructing crop growth models in future research. [ABSTRACT FROM AUTHOR]

The molecular crystals of acridonyl-tetraphenylethene (AD-TPE) exhibit an intriguing turn-on and color-tuned luminescence in response to mechanical grinding and hydrostatic compression. On the basis of in-depth experimental and computational studies, it is hypothesized that the origin of the piezochromic behavior from the D-phase to the B-phase is the change of the intramolecular geometrical conformation, especially for the torsion angle between the TPE and AD moiety. The different molecular conformation in the two distinctive solid phases causes the substantial switching of the intra­molecular charge transfer (ICT) process, which can be directly correlated with the subsequent fluorescence from locally excited (LE) state and ICT state in both phases. The AD-TPE molecular system presents a very rare example of high-contrast reversible fluorescence tuning driven by a switching of the excited state in the solid state under the mechanical stimuli, and thus provides a novel mechanism of the piezochromic behavior. [ABSTRACT FROM AUTHOR]

Molybdenum carbide (Mo 2 C) has gained significant recognition as a cutting-edge, non-precious transition metal catalysts for efficiently driving the hydrogen evolution reaction (HER). However, the desorption of Mo-H bonds on the pristine Mo 2 C surface are difficult, resulting in a slow Heyrovsky/Tafel step. Herein, biphasic Mo 2 C/Mo 16 N 7 nitrogen doped carbon nanorods (Mo 2 C/Mo 16 N 7 @NRs) is synthesized as the high-performance HER electrocatalyst by using a one-step in-situ pyrolysis growth method. It is found that a suitable pyrolysis temperature can simultaneously tune the morphology of the catalyst and form abundant heterointerface. Benefit from abundant porous nanostructure and more electron-rich Mo active sites at the Mo 2 C-Mo 16 N 7 interfaces, the optimized Mo 2 C/Mo 16 N 7 @NRs demonstrates exceptional catalytic activity. It achieves low overpotentials (η 10) of 63.62 and 117.43 mV at 10 mA cm−2, accompanied by Tafel scopes of 49.73 and 64.44 mV dec−1 in both alkaline and acidic electrolytes. Also, Mo 2 C/Mo 16 N 7 @NRs shows long-lasting stability for 24 h in the different electrolytes. The experimental and theoretical findings explain the synergistic effects of unique morphology control and interface engineering on electrocatalyst activity. The one-step in-situ pyrolysis growth method is expected to produce non-precious metal catalysts with distinct morphology and heterointerfaces. The morphology control and interface engineering are achieved simultaneously. The synergistic effects of morphology and heterointerfaces improve HER activity. The rod-like Mo 2 C/Mo 16 N 7 @NRs have superior HER electrochemical activity. DFT calculation explains the HER reaction kinetics mechanism of Mo 2 C/Mo 16 N 7. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction (OER) is a key half-reaction in renewable energy-related technologies, such as the electrocatalytic water splitting process and carbon dioxide reduction reaction. Unfortunately, developing an efficient and stable electrocatalyst to overcome the sluggish kinetics of OER remains a challenge. Herein, uniformly dispersed NiO and FeNi 3 alloy nanoparticles anchored on N-doped porous carbon (NC) electrocatalysts were designed and synthesized by a facile two-step calcination strategy. The influence of calcination temperature and the molar ratio of Ni:Fe on electrocatalytic OER activity was particularly studied. With an optimal calcination temperature and Ni/Fe ratio, FeNi 3 @NC-800 exhibited outstanding OER performance with a low overpotential of 242 mV at a current density of 10 mA cm−2 and a small Tafel slope of 34.7 mV dec−1 in alkaline media. The enhanced OER activity of FeNi 3 @NC-800 is mainly due to the synergistic effect of FeNi 3 alloy nanoparticles with NC and the high electrical conductivity between FeNi 3 and NC. This research will offer a new perspective on the construction of efficient and stable non-noble metal OER electrocatalyst. • Uniformly dispersed FeNi 3 NPs anchored on NC were designed and synthesized. • The electrocatalysts exhibited outstanding OER performance in alkaline media. • The activity owing to the synergistic effect and uniform dispersion. • The tight connection between FeNi 3 and NC improve the conductivity and stability. [ABSTRACT FROM AUTHOR]

Metabolic signaling to chromatin often underlies how adaptive transcriptional responses are controlled. While intermediary metabolites serve as co-factors for histone-modifying enzymes during metabolic flux, how these modifications contribute to transcriptional responses is poorly understood. Here, we utilize the highly synchronized yeast metabolic cycle (YMC) and find that fatty acid β-oxidation genes are periodically expressed coincident with the β-oxidation byproduct histone crotonylation. Specifically, we found that H3K9 crotonylation peaks when H3K9 acetylation declines and energy resources become limited. During this metabolic state, pro-growth gene expression is dampened; however, mutation of the Taf14 YEATS domain, a H3K9 crotonylation reader, results in de-repression of these genes. Conversely, exogenous addition of crotonic acid results in increased histone crotonylation, constitutive repression of pro-growth genes, and disrupted YMC oscillations. Together, our findings expose an unexpected link between metabolic flux and transcription and demonstrate that histone crotonylation and Taf14 participate in the repression of energy-demanding gene expression. • Histone lysine crotonylation (Kcr) oscillates in the yeast metabolic cycle (YMC) • Deregulation of crotonyl-CoA metabolism results in YMC defects • Taf14, a histone Kcr reader, is needed for transcription oscillations in the YMC • Kcr reading by Taf14 reduces growth gene expression during nutrient limitation Adaptive responses during environmental nutrient fluctuations are critical for survival. For example, during nutrient limitation, energy-demanding cell growth programs need to be tempered. Gowans et al. report that histone crotonylation, produced by fatty acid β-oxidation, is important for reduction of growth gene expression and promotion of metabolic homeostasis. [ABSTRACT FROM AUTHOR]

Francisella tularensis causes a highly infectious zoonotic disease tularemia. Both Haemaphysalis longicornis and Hyalomma asiaticum are widely distributed in China, but the presence of Francisella and Francisella-like endosymbionts (FLEs) in the two tick species is poorly understood. Therefore, a total of 627 H. longicornis (471 adults and 156 nymphs) and 88 Hy. asiaticum ticks (adults) were collected, of which 88 were from Bole of Xinjiang, 236 from Liaoyang, and 176 from Shenyang of Liaoning, and 215 from Wuhan of Hubei. Notably, five H. longicornis pools from Liaoyang of Liaoning province might have harbored F. tularensis, showing a minimum prevalence of 2.12% (5/236). This study should alert the health department and veterinarians working within the region to prevent and control the emergence of tularemia. After the screening of 16S rRNA and tul4 genes, the results revealed that FLEs were detected in Hy. asiaticum ticks in Bole and in H. longicornis ticks in Liaoyang and Shenyang. Their infection rate was 100% (88/88), 3.39% (8/236 is a minimum), and 8.52% (15/176), respectively. Phylogenetic analyses indicated that the sequence named bole in Hy. Asiaticum from Bole, the sequence named liaoyang1 in H. longicornis from Liaoyang, and the sequence named shanyang1 in H. longicornis from Shenyang shared consistent 16S rRNA sequence, and the difference between Chinese FLEs and the known FLEs was obvious. These findings suggest that this FLE species might be a potentially novel FLE circulating in H. longicornis and Hy. asiaticum from China. [ABSTRACT FROM AUTHOR]

In our previous research, we found that the laser induction process on commercially available polyimide sheets is a cost-effective method for the formation of porous graphene that can be subsequently fabricated into mechanically flexible devices. Here we study the parameters required for the formation of varied laser-induced graphene (LIG) morphologies by tuning the laser radiation energy. It was found that a critical fluence point of ∼5 J/cm 2 is needed to initiate the carbonization process regardless of the laser power. When increasing the radiation energy, the physical formation of LIG follows a fluid dynamics process in that the morphology of the LIG progressively changes from sheets to fibers and finally to droplets. We then demonstrate that a morphology of LIG nanomaterial, LIG fibers (LIGF), can be generated by this one-step laser photothermolysis process at a radiation energy >40 J/cm 2 . The LIGF are hollow with a LIG wall and form vertically aligned fibers up to 1 mm in height. Microsupercapacitor (MSC) devices fabricated from LIGF and LIGF-LIG hybrids show 2× the specific areal capacitance over MSCs made entirely from LIG, thereby underscoring the potential for LIGF in flexible device applications. [ABSTRACT FROM AUTHOR]

BiFeO 3 (BFO)/YBCO heterostructures are fabricated on (001)-oriented SrTiO 3 substrates. The transport properties of BFO/YBCO heterostructures with Au and YBCO top electrode are investigated. The Au/BFO/YBCO heterostructures show obvious rectification effect. The current through Au/BFO/YBCO heterostructures at positive bias is mainly bulk-limited space-charge-limited current (SCLC) at temperatures from 15 K to 280 K. As the applied voltage on Au electrode is negative, Au/BFO/YBCO heterostructures satisfy the interface-limited Schottky emission at temperatures from 220 K to 300 K, instead of interface-limited Fowler-Nordheim tunneling at temperatures from 15 K to 80 K. The leakage current density is reduced by two orders of magnitude through substituting the Au electrode by YBCO electrode. The transport mechanism in YBCO/BFO/YBCO heterostructures also changes to SCLC. The different leakage mechanisms result from the reduced oxygen vacancies because the fabrication of YBCO layer increased oxygen concentration in BFO films. [ABSTRACT FROM AUTHOR]

200 nm Ni film is coated on 25 μm thick Mo foil, and graphene is grown on the Ni–Mo system by CVD method. After the annealing process of CVD, the Ni/Mo bilayer transforms into Ni–Mo alloy, then we have successfully fabricated MgB 2 films on graphene/Ni–Mo alloy system via the hybrid physical–chemical vapor deposition (HPCVD) technique. The transition temperature T c onset is 38.25 K with a corresponding transition width of 0.75 K. The average thickness of MgB 2 films is 200 nm (25% concentration B 2 H 6 ). The critical current density derives from the magnetization measurement at 5 K is, j c (5 K, 0 T) = 9.6 × 10 6 A/cm 2 . We can easily deposite MgB 2 on graphene/Ni–Mo alloy system with a lower B 2 H 6 concentration and less gas flow, which lays a good foundation for depositing MgB 2 thick films. The graphene in this system is multilayer and with defects, it may act like an intermediary film for the growth of MgB 2 , or a carbon-doping source. [ABSTRACT FROM AUTHOR]

Two 9,10-distyrylanthracene (DSA) derivatives CNDSA and t-BUDSA were designed and synthesized, and their photophysical properties and crystal structures were investigated. Compared to DSA, the maximum emission peaks of the two compounds showed red-shift not only in THF solution, but also in crystals, because the introduction of electron-withdrawing substituents to DSA leads to more dispersion of the electrons in the molecules. The two crystals of CNDSA and t-BUDSA show strong fluorescence with the efficiency Φ of 45% and 33%, respectively, which may be resulted from no obvious π-π interactions between molecules inside the crystal due to the large distance between the two adjacent molecules and nearly no overlap between the central anthracene planes. The analysis of crystal structures of the two compounds indicated that the molecules are arranged in the same conformation and orientation in their crystals, i.e. uniaxially oriented packing crystal, because of the supramolecular interaction of CH/π in the two crystals and additional C-H...N interactions in CNDSA. [ABSTRACT FROM AUTHOR]

A series of poly(p-phenylenevinylene) based polymers (MEH-OXD-PPVs) functionalized with Y-shaped double 1,3,4-oxadiazole-containing side chains were synthesized through a modified Gilch reaction. They are all soluble in common organic solvents such as chloroform, tetrahydronfuran and 1,1,2,2-tetrachloroethane. The chemical structures of MEH-OXD-PPVs were determined by 1H NMR, GPC and elemental analysis. Thermogravimetric analysis shows that they have good thermal stability with the decomposition temperature ranging from 312 °C to 326 °C. The absorption and fluorescence emission maxima of the polymers exhibit an appreciable blue-shift with the increase of oxadiazole-containing moieties. Electrochemical investigation shows that the HOMO energy levels of the polymers vary regularly with the change of content of oxadiazole-containing moieties. Additionally, by introducing more OXD-PV unit during copolymerization, the PL quantum efficiencies of the polymers are significantly enhanced compared to that of MEH-PPV. The successful manipulation of optical and electronic properties of the MEH-OXD-PPVs indicates an effective concept for developing PPV-based functional materials with tunable optoelectronic properties by changing the amount of electron-withdrawing oxadiazole-containing moieties. [ABSTRACT FROM AUTHOR]

Abstract: We report the efficiency enhancement of polymer solar cells by incorporating a silver nanodisks'' self-assembled layer, which was grown on the indium tin oxide (ITO) surface by the electrostatic interaction between the silver particles and modified ITO. Polymer solar cells with a structure of ITO (with silver nanodisks)/poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) (Clevious P VP AI 4083)/poly(3-hexylthiophene):[6,6]-phenyl-C61 butyric acid methyl ester (P3HT:PC61BM)/LiF/Al exhibited an open circuit voltage (V OC) of 0.61±0.01V, short-circuit current density (J SC) of 9.24±0.09mA/cm2, a fill factor (FF) of 0.60±0.01, and power conversion efficiency (PCE) of 3.46±0.07% under one sun of simulated air mass 1.5 global (AM1.5G) irradiation (100mW/cm2). The PCE was increased from 2.72±0.08% of the devices without silver nanodisks to 3.46±0.07%, mainly from the improved photocurrent density as a result of the excited localized surface plasmon resonance (LSPR) induced by the silver nanodisks. [Copyright &y& Elsevier]

Abstract: Semi-transparent inverted polymer solar cells (PSCs) were fabricated by all-spin-coating vacuum-free process. An interfacial layer of poly(allylamine hydrochloride) and dextran (PAH-D) was introduced to modify the surface wettability of poly(3-hexylthiophene) (P3HT):[6,6]-phenyl C61-butyric acid methyl ester (PCBM) film for depositing aqueous-solution-processed poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) (CLEVIOS™ PH500) (PH500) anode as well as enhancing the adhesion and bonding strength between the active layer (P3HT:PCBM) and conducting polymer electrode (PH500). The photovoltaic performance of the semi-transparent PSCs under top and bottom illumination was investigated and the highest PCE of about 1.86% was achieved under simulated AM 1.5 illumination (100mW/cm2) from the bottom side with a reflective white paper back side. The semi-transparent Cell A have the potential for use as energy-generating color window glasses as well as the subcell of tandem solar cells. The all-spin-coating vacuum-free processing provides a possibility of high-throughput all-solution-processed fabrication of PSCs by roll-to-roll processing. [Copyright &y& Elsevier]

Abstract: A series of novel soluble conjugated copolymers consisting of electron-accepting 2-pyran-4-ylidenemalononitrile (PM) and electron-donating fluorene connected by different electron-donating ability conjugated moieties were synthesized by Suzuki coupling polymerization. The structures of the copolymers were characterized and their physical properties were investigated. High molecular weight (M n up to 43.8kg/mol) and thermostable copolymers were obtained. The conjugated bridge between PM and fluorene building block with gradually increased electron-donating ability moieties results in enhanced intramolecular charge transfer (ICT) transition bands, which lead to an extension of their absorption spectral range. Cyclic voltammetry measurement displayed that the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of the copolymers can be fine-tuned. The resulting copolymers possessed relatively low HOMO energy levels, promising good air stability and high open circuit voltage (V oc) for photovoltaic application. Bulk heterojunction photovoltaic devices were fabricated by using the copolymers as donors and (6,6)-phenyl C61-butyric acid methyl ester (PCBM) as acceptor. The power conversion efficiencies (PCE) of the devices were in the range of 0.02–0.52% under simulated AM 1.5 solar irradiation of 100mW/cm2, and the highest V oc reached 0.82V. The significant improvement of PCE indicates a novel concept for developing donor–acceptor (D–A) conjugated copolymers with high photovoltaic performance by adjusting electron-donating ability of conjugated bridge. [Copyright &y& Elsevier]

To meet the food demands of a growing population, the maize production systems deployed by smallholders in China have tended towards extremely intensive planting and excessive use of fertilizers, which have caused serious environmental impacts. This study investigated the balance between the maize yield and nitrogen (N) input in the North China Plain (NCP), which is one of the most important grain-producing region in China. Our study compared yield simulations generated by the DSSAT-CERES-Maize model with actual data from a number of multi-site field experiments and an extensive household surveys encompassing 1671 farmers. The smallholders' maize cultivars, plant population, and amount of N input on the crop yield and how these affects the economic benefits were analyzed. The results showed that the average traditional farming methods' yield was 72% of the attainable yield, which means that farmers have ample room to improve their yields. We also found that the maize yields varied widely between farmers, and that most of them applied excessive amounts of N but failing to achieve an optimal yield due to poor fertilization management techniques. The study found that the economic benefits achieved by the farmers were low, but after deploying high-yield (HY) methods, the yield was increased by 34.9% and the economic benefits by 14.4%. The greenhouse gas (GHG) emissions associated with the traditional farming methods were high and could potentially be reduced by 48.6%. All in all, farmers should be given guidance on how to appropriately increase the plant population, reduce the input of N fertilizer, and optimize farmland management measures, so that China can achieve intensive but sustainable agricultural production at a lower environmental cost. It was concluded that there are still numerous biological and abiotic factors that restrict production increases by smallholders. These factors vary from region to region and require further investigation. Unlabelled Image • Smallholders use inappropriate maize cultivars and cultivation management measures. • The fertilizer management by farmers exhibits regional variability. • Farmers could achieve higher yields and economic benefits with lower GHG emissions. • The factors limiting the farmers' maize yield vary from region to region. [ABSTRACT FROM AUTHOR]