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High-potency 4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitors are usually featured by time-dependent inhibition. However, the molecular mechanism underlying time-dependent inhibition by HPPD inhibitors has not been fully elucidated. Here, based on the determination of the HPPD binding mode of natural products, the π-π sandwich stacking interaction was found to be a critical element determining time-dependent inhibition. This result implied that, for the time-dependent inhibitors, strengthening the π-π sandwich stacking interaction might improve their inhibitory efficacy. Consequently, modification with one methyl group on the bicyclic ring of quinazolindione inhibitors was achieved, thereby strengthening the stacking interaction and significantly improving the inhibitory efficacy. Further introduction of bulkier hydrophobic substituents with higher flexibility resulted in a series of HPPD inhibitors with outstanding subnanomolar potency. Exploration of the time-dependent inhibition mechanism and molecular design based on the exploration results are very successful cases of structure-based rational design and provide a guiding reference for future development of HPPD inhibitors.

4-Hydroxyphenylpyruvate dioxygenase (HPPD) is a functional protein existing in almost all aerobic organisms. In the field of agricultural chemicals, HPPD is acknowledged to be one of the crucial targets for herbicides at present due to its unique bio-function in plants. In the Auto Core Fragment

Unmanned Aerial Vehicles (UAVs) are being used in different emerging domains for accomplishing many critical tasks. However, due to the various constraints like – battery life, computational resources, etc., an UAV under a mission (M-UAV) often needs assistance from an edge/cloud server that is reachable from the M-UAV’s location. A connection between an M-UAV and edge server can be established via an access point or AP. Therefore, before sharing any sensitive information with the edge server, it is essential for an M-UAV to determine the legitimacy of the selected AP. Recently, some works in this direction indicate that a rogue UAV (R-UAV) can successfully mimic a legitimate AP for intercepting the communication channel. Hence, there should be a robust detection mechanism in place for addressing such a threat scenario. In this paper, considering one of the emerging domains – the Internet of Vehicle (IoV) networks, at first, we show that communication in the IoV networks can get benefit from the presence of M-UAVs. However, as the link between the M-UAV and edge server can be intercepted by an R-UAV, the adversary may access the sensitive information from the IoV networks. Followed by this, we propose a timing-based algorithm for identifying the presence of rogue APs (or R-UAVs) in the channel. The M-UAV executes the timing-based algorithm, and the detection method does not require any auxiliary hardware or any modification to the network protocols for meeting the objective. Supported by an extensive evaluation study, we show that without any rigid restriction on the M-UAV’s speed (e.g., by limiting it to almost static) the proposed approach significantly enhances the detection accuracy (at least by a margin of 29.7% and 16.65%) compared to the state-of-the-art methods.

Variable-rate mechanism has improved the flexibility and efficiency of learning-based image compression that trains multiple models for different rate-distortion tradeoffs. One of the most common approaches for variable-rate is to channel-wisely or spatial-uniformly scale the internal features. However, the diversity of spatial importance is instructive for bit allocation of image compression. In this paper, we introduce a Spatial Importance Guided Variable-rate Image Compression (SigVIC), in which a spatial gating unit (SGU) is designed for adaptively learning a spatial importance mask. Then, a spatial scaling network (SSN) takes the spatial importance mask to guide the feature scaling and bit allocation for variable-rate. Moreover, to improve the quality of decoded image, Top-K shallow features are selected to refine the decoded features through a shallow feature fusion module (SFFM). Experiments show that our method outperforms other learning-based methods (whether variable-rate or not) and traditional codecs, with storage saving and high flexibility., Comment: Accepted by IEEE ICASSP2023 (Camera Ready)

A three-dimensional (3D) metal-organic framework (MOF) of [Et

Magnetically stirrable photocatalysts binding the ZnS-decorated Ni foam with the metal complex cocatalyst as a redox mediator and light-absorbing composition were investigated. Loading metal complex can improve light absorption, surface hydrophilicity, interfacial charge migration, and H

Secondary building units (SBUs) in metal–organic frameworks (MOFs) are essential from both a structural and performance perspective. While a variety of SBUs, such as paddlewheel CuII2, triangular CrIII3, tetrahedral ZnII4, and octahedral ZrIV6 have been extensively studied, the linear trinuclear SBUs (herein denoted as M3), though frequently encountered, are rarely discussed as a class. A literature survey reveals that M3 clusters are ubiquitous in discrete molecular entities as well as in MOFs. Unlike most other cluster types, however, they have an unprecedented metal diversity and ligand tolerance. The single-crystals of some M3-based MOFs are also sufficiently robust upon guest removal and exchange or multi-step post-modifications to enable catalytic mechanism elucidation. Some of these M3-based SBUs endow MOFs with stability under demanding conditions necessary, for example, in flue gas separation. Herein we review MOFs sustained by this common but under-appreciated class of SBUs and discuss applications of the resulting MOF motifs.

In recent times, Unmanned-aerial-vehicles (UAVs) have grasped significant attentions for performing various operations without a constant intervention of the human users. Due to the power and computing constraints, however, it is difficult for an UAV to perform all the tasks independently. Hence, to achieve its goals, a UAV may share various sensitive data with the nearest edge servers through some access points (APs). Prior to sending any sensitive information through an AP, it is very important for an UAV to determine the authenticity of the selected AP. In this paper, we have applied a timing-based algorithm for spotting rogue APs by the UAVs − while selecting an edge server. The timing-based algorithm does not require any additional hardware or any change in the network protocol for detection purpose. This fact, in turn, reduces the effort from UAV’s side for detecting a breach. An extensive experimental study shows that with a little manipulation in speed, an UAV can detect the presence of any rogue AP almost every time with only 6% false-positive rate.

Oxetanocin A (Oxt-A), a novel oxetanosyl N-glycoside nucleoside, was isolated from Bacillus megaterium in 1986. It carries an oxetane ring on the sugar moiety of the nucleoside scaffold, which contributes to differences in its structure from those of common tetrahydrofuranyl-based nucleosides. In view of the unique 3D-spatial framework, the complete synthesis of Oxt-A has been achieved by multiple research groups. The pharmacological properties of this natural product have also been broadly investigated by pharmacists and chemists since its discovery. Notably, the potential antiviral effect of Oxt-A has captured attention of researchers in the field of antiviral agent development. Furthermore, epidemic outbreaks caused by viruses have been stimulating the preparation and modification of various Oxt-A analogs over the past few decades. However, none of the studies have overviewed the antiviral efficacies of this naturally occurring scaffold yet. Thus, the present review summarizes the synthesis, structural modification, and antiviral activities of Oxt-A and its derivatives. We believe that these comprehensive descriptions will provide a novel perspective for the discovery of antivirus drugs with well-improved performance and pave newer paths for combating sudden public health issues triggered by viruses in the future.

The Australasian biogeographic realm is a major centre of diversity for orchids, with every subfamily of the Orchidaceae represented and high levels of endemism at the species rank. It is hypothesised that there is a commensurate diversity of viruses infecting this group of plants. In this study, we have utilised high-throughput sequencing to survey for viruses infecting greenhood orchids (Pterostylidinae) in New South Wales and the Australian Capital Territory. The main aim of this study was to characterise Pterostylis blotch virus (PtBV), a previously reported but uncharacterised virus that had been tentatively classified in the genus Orthotospovirus. This classification was confirmed by genome sequencing, and phylogenetic analyses suggested that PtBV is representative of a new species that is possibly indigenous to Australia as it does not belong to either the American or Eurasian clades of orthotospoviruses. Apart from PtBV, putative new viruses in the genera Alphaendornavirus, Amalgavirus, Polerovirus and Totivirus were discovered, and complete genome sequences were obtained for each virus. It is concluded that the polerovirus is likely an example of an introduced virus infecting a native plant species in its natural habitat, as this virus is probably vectored by an aphid, and Australia has a depauperate native aphid fauna that does not include any species that are host-adapted to orchids.

The development of an in-vacuum long trace profiler (IVLTP) which can provide ultra high precision real time measurements on the surface slope of optical elements is reported. The unique features of this instrument include a specifically designed ultra high repeatability linear slide, a pentamirror composed of two plane mirrors of ultra low slope error, and an ultra high vacuum (UHV) compatible complementary metal oxide semiconductor (CMOS) image sensor. The mechanical system is made of Invar 36 alloy to reduce the room temperature drift effect during data acquisitions. Each IVLTP scan completes in 120 seconds, covering a 168 mm of surface length and generating more than 5000 slope data points. The root mean square (RMS) of the difference between two consecutive scans was found to be 0.0081 μrad on average and 0.0045 μrad RMS at its best. The main application of this IVLTP is to provide the real time feedback signals needed for controlling the 25-actuator surface benders of the active mirrors and active gratings installed in the ultra high resolution soft X-ray beamlines at the Taiwan Photon Source (TPS).

A series of Ce-doped LaMnO3 (La1-xCexMnO3) were prepared and were tested for gaseous toluene oxidation in order to investigate the effect of cerium doping in LaMnO3 on activity under photothermal conditions. It was found that the activity and CO2 yield of the catalyst can be effectively increased when x = 0.25. A group of characterization is used to characterize the morphology, composition, and physical properties of the as-prepared catalysts. Results show that the Ce-doped LaMnO3 can form coexistence of La1-xCexMnO3 and CeO2, the reaction of CeO2/La1-xCexMnO3 under photothermal conditions follows the Mars-van Krevelen redox cycle mechanism, and the prepared CeO2/La1-xCexMnO3 can form a highly efficient Z-scheme heterojunction, which can enhance the electrons transfer speed of the catalyst. Moreover, in the photothermal catalytic degradation, lattice oxygen is the most important active substance, a small amount of cerium doping can increase the lattice oxygen content of perovskite and increase the activity of the reaction.

Stainless steel wire mesh/bismuth oxybromide (BiOBr) were synthesized as immobilized photocatalysts. The effects of conductive wire mesh substrate and calcination on the photocatalytic performance were investigated. The morphology, crystal structure, composition, and optical properties of hierarchical wire mesh/BiOBr photocatalyst were investigated. The degradation of 99% dye can be achieved within 50 min by S250 photocatalyst which was calcined at 250 °C. The recycled photocatalyst also shows good stability. The activity of the immobilized photocatalysts was enhanced by increasing the surface area (flower-like texture of BiOBr), facilitating separation of photogenerated charge carriers (good contact between BiOBr and conductive stainless steel wire mesh), and improving the crystal properties (facet effect, dominant (001) facets by calcination). This study provides a way to optimizing the activity of immobilized photocatalysts for the treatment of hazardous pollutants in wastewater.

Ni-doped ZnS nanomaterials were decorated on the surfaces of porous Ni foam as immobilized photocatalysts for H 2 production by a solvothermal process. Effects of the Ni dopant content on the photocatalytic hydrogen production activity, morphology, optical property, crystalline properties, surface wetting, and photocurrent were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), photoluminescence (PL), photocurrent response, and contact angle meter. The surface changed from hydrophobic to superhydrophilic by decorating Ni-doped ZnS on the NiO/Ni foam substrate. A mechanism is proposed to elucidate the band positions of ZnS and NiO, together with the transfer of photoinduced electrons among ZnS, NiO, and Ni foam. The Ni-doped ZnS/NiO/Ni foam photocatalyst NZ5 showed much higher photocatalytic activity because of the matched band structure and the high conductivity of Ni foam. Meanwhile, the porous texture and superhydrophilic nature of the photocatalyst favor the light trapping, effective mass transfer of reactant molecules, and provide large contact area. Ni doping leads to a decreased band gap. The highest photocatalytic H 2 generation activity reached 2500 μmol/g −1 h −1 . After being operated for 3 cycles, the activity of the third run was 85% of that obtained at the first run.

Ruthenium(II) complexes bearing a tridentate bis(N-heterocyclic carbene) ligand reacted with iminoiodanes (PhI=NR) resulting in the formation of isolable ruthenium(III)-amido intermediates, which underwent cleavage of a C-N bond of the tridentate ligand and formation of an N-substituted imine group. The RuIII -amido intermediates have been characterized by 1 H NMR, UV/Vis, ESI-MS, and X-ray crystallography. DFT calculations were performed to provide insight into the reaction mechanism.

Microexplosions are reported to occur frequently in droplet combustion of biodiesel mixed with alcohol, which are nominally miscible. We found, however, that they could be prevented if the standing time of fuel samples before burning was sufficiently long. To realize the microexplosion mechanisms, experiments based on suspending droplets and free-falling droplets were conducted. It was found that, before ignition, heterogeneous sites, which appeared similar to small drops, emerged from the droplet surface and subsequently merged into a bigger one, which then deposited at the bottom of the droplet. The diameter of this heterogeneous drop enlarged with increasing ambient humidity. At the same humidity, by using methanol, ethanol and isopropanol, respectively, the experiments showed that the merged heterogeneous drop of biodiesel/methanol was the largest and the smallest one was generated by that mixed with isopropanol. These heterogeneous sites were likely caused by the hygroscopic characteristics of alcohol fuels, which were supposed to mix well with biodiesel fuel and treated as a miscible blend in the first place. The miscibility, however, was destroyed by the absorbed water and phase separation occurred, leading to microexplosions when the droplet was burned. On the other hand, the interior heterogeneous drop vanished after sufficiently long time of standing prior to burning, and consequently no microexplosion was observed during the whole combustion process. For the mixture fuel of alcohol, methanol had higher propensity to absorb water and needed longer standing time for dissolution of the heterogeneous drop, as compared to ethanol and isopropanol, which had lower hygroscopicity. From the results, the heterogeneous sites inside the blended droplet were concluded unambiguously to be the primary cause of microexplosions during the combustion process, leading to the highest burning rate at equi-volume proportion of mixed fuels. In contrast, elimination of the heterogeneous sites in the burning droplets could prohibit microexplosions and yielded the highest burning rate at 25% fraction of alcohol.

Despite the positive potential of the online social networking platforms, the longitudinal studies regarding how children participate in digital storytelling communities is still scant in the literature. This study investigated how 26 elementary students participated in a 2-year digital storytelling community mediated by a social network application. By analyzing the students’ weekly responses, social networks, and their language learning performance, the results suggested that their oral reading proficiency improved along with their participation in the long-term activity. It was also found that the community features impacted the students’ sense of engagement in the activity. The feature of the learning community that allows students to team up with partners to complete a story improved their engagement and motivation. The social network analysis found that multiple literacies including multimedia processing, language, and collaboration were all considered by students as important criteria for the partnership to complete the collaborative digital storytelling work. However, such a prolonged collaborative digital storytelling activity also introduced new challenges for those students demonstrating unfavorable collaboration profiles as they needed to learn how to collaborate in order to team up with others. The implications of the findings for educational practice are discussed.

BiOI-based photocatalysts were proved to exhibit photocatalytic H2 production activity. AgI-BiOI-graphene showed better H2 production activity than BiOI and BiOI-graphene. The surface chemistry, electronic property, phase structure, morphology, optical property and photocatalytic performance of these photocatalysts were studied. The interfacial electronic states of the photocatalysts were investigated through their C K-edge near-edge X-ray-absorption fine-structure (NEXAFS) spectra. Based on the in situ NEXAFS spectra measured with and without illumination, a mechanism about the transport of photoelectron from AgI to graphene through BiOI is proposed for the photocatalytic H2 production process. The incorporation of graphene restricted the three-dimensional self-assembly of BiOI nanocrystals and led to the formation of less extensively crystallized BiOI domains through a confined-space effect. Addition of AgNO3 precursor altered the crystal structure of BiOI from flower-like to horizontally stacked flat plates. The results of NEXAFS spectra, photoluminescence spectra and photocurrent tests reveal that the improved photocatalytic activity of the AgI-BiOI-graphene photocatalyst is attributable to the interfacial interaction among AgI, BiOI and graphene, which enhanced the separation of photogenerated electrons to generate H2. AgI-BiOI-graphene photocatalyst was a stable photocatalyst for the production of H2. After three cycles, 86% activity of recycled photocatalysts was retained.

A series of metal oxides (MnFeOx, MnCrOx, MnTiOx, and MnFeTiOx) supported on attapulgite (ATP) were synthesized by coprecipitation for the low-temperature selective catalytic reduction (SCR) of NOx with NH3. Then, they were subjected to appropriate characterizations for their properties (XRD, TEM, BET, XPS, etc.). The catalytic activity of MnFeTiOx/ATP catalyst was over 95% NOx conversion within a wide temperature window between of 175 and 300 °C, and 88% N2 selectivity. Moreover, MnFeTiOx/ATP presented excellent potassium resistance relative to the traditional V–W–Ti catalyst, and its denitration performance was significantly improved. The NOx conversion rate could be restored to nearly 90% at 210 °C after removing potassium via washing of K–MnFeTiOx/ATP. In addition, the MnFeTiOx/ATP showed better SO2 resistance and stability than the traditional V–W–Ti catalyst. Therefore, the MnFeTiOx/ATP catalyst has been proved to have broad prospects in NH3-SCR.

Fatty acid (FA) composition between biofilms and batch planktonic cultures were compared for two bacterial species Pseudomonas aeruginosa and Staphylococcus aureaus. Biofilm cultures exhibited decrease in saturated fatty acids (SAFA) that potentially conform to a more fluidic biophysical membrane property. The amount of FA in the biofilms' extracellular polymeric substance was not sufficient to consider it having a major contribution to the observed differences between biofilms and batch planktonic cultures. While biofilm grazing by the amphipod Hyalella azteca was evident, only certain bacteria-specific FA appeared to have the potential to be retained (odd-number SAFA and branched-chain FA). H. azteca with diet strictly consisted of bacteria biofilms did not demonstrate significant changes in their nutritional condition in terms of ω-3 and ω-6 polyunsaturated fatty acids (PUFA): combined with the results from fasting trials, H. azteca appears to have the capacity to retain ω-3 and ω-6 PUFAs up to 10 days.

To explore the clinical features, prognosis and survival of patients with IgD multiple myeloma (MM).The clinical data of 20 patients with IgD MM was analyzed retrospectively. The prognostic factors and survival analysis was carried out. We summarized their clinical characteristics. The survival analysis was carried out by Kaplan-Meier method, and the prognostic factor were analyzed by using log-rank test for single factor analysis of observation index. Variables of P0.15 in single factor analysis were enrolled in multifactor cox regression analysis.IgD MM patients accounted for 4.3% of all MM patients in the same period, among which 80% were male, the median age of patients was 57.5(35-77) years old, 90% of the patients belongs to λ light chain type. At the time of diagnosis, 18 patients (90%) were in DS-Ⅲ stages, while 10 patients were in ISS-Ⅲ stage. The first clinical manifestations were fatigue, bone pain, kidney function impairment, anemia (Hb100 g/L) in 14 cases (70%), 12 cases (60%) with osteolytic bone destruction≥3, combined with renal impairment in 8 cases (40%), and elevated blood calcium in 11 cases (51.4%). In only 5 patients the ratio of albumin to globntin was inverted, hypoalbuminemia accounted for 40%, and globulin increase accounted for only 15%. FISH results showed that the positive rate of 1q21 amplification (50%) was the highest, and it was easy to occur at the same time as other cytogenetic abnormalities. Extramedullary infiltration occurred in 4 cases (20%). The analysis of prognostic factors showed that only the increase of lactate dehydrogenase (LDH) level was an independent poor prognostic factor for IgD MM patients. Extramedullary infiltration and various cytogenetic abnormalities were found in 2 IgD MM patients with primary drug resistance, suggesting that extramedullary infiltration and various cytogenetic abnormalities may be prognostic factors, but the difference was not statistically significant, Which maybe related to the small sample size. All 20 patients were treated with bortezomib-containing regimen, of which 19 patients were evaluated, 17 patients (89.4%) showed effective, including CR+VGPR (52.6%), PR (31.5%), MR (5.3%), 2 patients primary drug resistance. The median PFS and OS was 9.5 and 10.5 months, respectively.IgD MM is a rare and invasive disease. Increased LDH is an independent prognostic factor. Bortizomib-containing regimen can improve the prognosis of IgD MM patients.IgD型多发性骨髓瘤患者临床特征及生存分析.探讨IgD型多发性骨髓瘤（MM）患者的临床特征、预后及生存.回顾性分析20例IgD型MM患者临床资料，总结其临床特征，分析预后因素及生存。采用Kaplan-Meier方法进行生存分析，预后因素分析应用Log-rank 检验，对观察指标进行单因素分析，单因素分析中P0.15的变量纳入多因素COX回归分析.IgD型MM患者占同期全部MM患者的4.3%,其中男性多见（占80%），中位发病年龄57.5（35-77）岁，以λ轻链型为主，占90%。DS-Ⅲ期18例（90%），ISS-Ⅲ期10例（50%），首发临床表现主要有乏力、骨痛、肾功能损害，贫血（血红蛋白100 g/L） 14例（70％），溶骨性骨质破坏≥3处者12例（60%），合并肾功能损害者8例（40％），血钙升高者11例（51.4％）。仅5例患者白球比例倒置，低白蛋白血症占40%，球蛋白升高者仅占15%。FISH结果显示，1q21扩增阳性发生率最高，占50%，且易与其他细胞遗传学异常同时出现。发生髓外浸润者4例（20％）。预后因素分析显示，仅乳酸脱氢酶水平升高是IgD型MM患者独立预后不良因素。2例原发耐药患者均存在髓外浸润及多种细胞遗传学异常，提示髓外浸润及多种细胞遗传学异常可能为预后不良因素，但差异不具有统计学意义，可能与样本量少有关。20例患者均使用含硼替佐米方案治疗，可评价疗效的有19例，17例（89.4%）患者治疗有效，其中CR+VGPR占52.6%、PR患者6例 （31.5%）、MR患者1例（5.3%），2例患者原发耐药。中位无进展生存时间及总生存时间分别为9.5和20.5个月.IgD型MM是一种少见且侵袭性较强的疾病，乳酸脱氢酶水平升高是这类患者的独立预后不良因素，含硼替佐米方案可改善IgD型MM患者的预后.

To investigate the effect of clinical baseline data on prognosis in patients with multiple myeloma (MM) complicated by extramedullary disease (EMD).The clinical data of 46 MM patients with EMD were retrospectively analyzed. The clinical data and survival prognosis of MM patients in primary EMD group and recurrent EMD group were analyzed. The classified baseline data were expressed by the number of cases (percentage), the χβThe remission depth of primary EMD group≥VGPR is lower than that of recurrent EMD group，and the OS time of patients in primary EMD group is shorter than that in recurrent EMD group. Bortezomib-based chemotherapy could not improve the prognosis of patients with primary EMD and recurrent EMD, and the prognosis of patients with primary EMD is even worse.多发性骨髓瘤伴髓外病变46例临床分析.探讨多发性骨髓瘤（MM）伴髓外病变（EMD）患者临床基线资料对预后的影响.回顾性分析伴髓外病变的46例MM患者的临床资料，分析初次住院时原发性EMD组和复发EMD组MM患者临床资料及生存预后的差异。分类基线资料采用例数（百分比）表示，二分类资料组间比较采用χβ原发性EMD组缓解深度达到≥VGPR较复发EMD组低；原发性EMD组OS时间短于复发EMD组。以硼替佐米为基础化疗方案未能改善原发性EMD组和复发EMD组患者预后，原发性EMD组患者的预后更差.

To explore the risk factors, prognosis and curative effect of elderly patients with MM renal damage.118 patients with primary elderly MM treated in our hospital from January 2011 to December 2018, were enrolled analyzed retrospectively. The clinical characteristics and prognosis of renal function impairment group (RI group) and normal renal function group (non-RI group) were compared. The difference of renal efficacy and survival benefit between the patients treated with bortezomib, thalidomide (combination group) and chemotherapy regimen containing only one of them (single drug group) in RI group was compared.Univariate analysis showed that DS stage, pulmonary infection, uric acid, βThe prognosis of elderly MM patients with impaired renal function is poor. The prognosis of these patients can be improved by selecting chemotherapy regimen containing bortezomib and thalidomide at the same time, and monitoring, controlling all kinds of risk factors actively.老年多发性骨髓瘤肾损害患者的临床特征、预后及疗效分析.探讨老年MM肾损害患者的临床特征、预后及疗效分析.对本院2011年1月-2018年12月收治的118例初发老年MM患者进行回顾性分析，比较肾功能损害组（RI组）及肾功能正常组（非RI组）MM患者的临床特点、预后，比较RI组同时包含硼替佐米、沙利度胺的化疗方案（联合用药组）与只包含其中之一的化疗方案（单药 组）的肾脏疗效及生存获益的差异.单因素分析表明，RI组DS分期、肺部感染、尿酸、β老年MM患者肾损害后预后较差，积极监测及控制各种危险因素、选择同时含有硼替佐米及沙利度胺的化疗方案可使该类患者的预后得到改善.

Nowadays the development of high-field magnets strongly relies on the performance of superconducting materials. Iron-based superconductors exhibit high upper critical fields and low electromagnetic anisotropy, making them particularly attractive for high-field applications, especially in particle accelerator magnets, nuclear magnetic resonance spectrometers, medical magnetic resonance imaging systems and nuclear fusion reactors. Herein, through an industrially scalable and cost-effective manufacturing strategy, a practical level critical current density up to 1.1x10^5 A/cm2 at 4.2 K in an external magnetic field of 10 T was achieved in Cu/Ag composite sheathed Ba0.6K0.4Fe2As2 superconducting tapes. The preparation strategy combines flat rolling to induce grain texture and a subsequent hot-isostatic-pressing densification. By varying the parameters of rolling, the degree of grain texture was engineered. It is found that the transport properties of the Ba1-xKxFe2As2 tapes can be enhanced by applying a large amount of deformation during rolling, which can be attributed to the improved degree of c-axis texture. Microstructure characterizations on the highest-performance tape demonstrate that the Ba1-xKxFe2As2 phase has a uniform element distribution and small grains with good connectivity. Grain boundary pinning is consequently enhanced as proved by large currents circulating through the sample even at 25 K. Our work proves that Cu/Ag composite sheathed Ba1-xKxFe2As2 superconducting tapes can be a promising competitor for practical high-field applications in terms of the viable, scalable and cost-effective fabrication strategy applied and the high transport properties achieved in this work., Comment: 30 pages, 7 figures, accepted to SCIENCE CHINA Materials

Crystals of a two-dimensional (2D) metal–organic framework (MOF) [Cd3(BTB)2(DEF)4]·2(DEF)0.5 (1; BTB = benzene-1,3,5-tribenzolate; DEF = N,N′-diethylformamide) immersed in a solution of trans-1,2-bis(4-pyridyl)ethylene (BPEE) yields an interpenetrated three-dimensional (3D) MOF of [Cd3(BTB)2(BPEE)(H2O)2]·(BPEE)·xSol (2). Crystals of MOF 2, in turn, undergo a cascade conversion when immersed in DEF, yielding [Cd3(BTB)2(BPEE)1.8(DEF)0.9(H2O)0.8]·xSol (3a) over 100 seconds and [Cd3(BTB)2(BPEE)2(DEF)2]·xSol (4) after one hour, before finally shuttling back to MOF 1 after six hours.

A mesoporous γ-Fe2O3-modified nanoflower-MnO2/attapulgite (γ-Fe2O3/nf-MnO2–ATP) catalyst was fabricated through a facile hydrothermal method. The results of TEM and XRD indicated that γ-Fe2O3/nf-MnO2–ATP presented a beautiful nanoflower shape and good dispersion. The BET results showed that the specific surface area and pore volume of γ-Fe2O3/nf-MnO2–ATP significantly increased after surface modification with γ-Fe2O3. Also, the XPS and NH3-TPD results illustrated that the γ-Fe2O3 coating could enhance the amounts of surface chemisorbed oxygen and acidic sites. SO2 and H2O tolerance tests and stability tests demonstrated that γ-Fe2O3/nf-MnO2–ATP can effectively inhibit SO2 and H2O poisoning and improve the stability of the catalyst. The superior SCR performance can be attributed to the abundant acid sites, the strong adsorption of NOx, and the formation of more oxygen vacancies as well as metal–metal interactions. Therefore, γ-Fe2O3/nf-MnO2–ATP was proved to be an excellent catalyst for NH3-SCR and may be of interest in other environmental catalysis applications.

The single-crystal to single-crystal (SCSC) conversion of metal–organic frameworks (MOFs) represents a facile route to new MOFs with structures and functionalities that are challenging to obtain by direct synthesis. However, conversion products are often structurally limited for a given precursor. We herein report that a two-dimensional (2D) MOF featuring a linear Cd3 cluster secondary building unit (SBU) converts into one type of three-dimensional (3D) interpenetrated and two types of 3D non-interpenetrated MOFs upon reaction with dipyridyl ligands. One of the interpenetrated 3D MOFs, in turn, undergoes either ligand substitution to give isoreticular interpenetrated MOFs, or ligand addition to give a self-penetrated 3D MOF. This rich SCSC conversion library is made possible by the inclined nature of the Cd3 SBU with respect to the 2D plane of the starting material to create an anisotropic environment around the SBU.

Help-seeking is an important aspect of self-regulated learning (SRL), but students may have ineffective help-seeking behaviors. For example, some students are unaware of their need to seek help, and some often seek executive help merely to obtain the correct answer. This study proposes a negotiation-based adaptive learning system with a help-seeking negotiation mechanism to form the co-regulation of help-seeking between a student and the system. The system provides external feedback on SRL as scaffolding for help-seeking by prompting students to seek help or even actively offering help when they need it and reminding students not to seek too much help. An experiment was conducted with student participants divided into control and experimental groups. Students in the control group were allowed to seek help at will, whereas the help-seeking of students in the experimental group was regulated by the system. The results indicated that the students in the experimental group had better help-seeking behaviors (a higher ratio of steps solved by themselves and a lower ratio of steps solved with executive help) than the students in the control group.

Novel cerium-loaded MnTiOx/attapulgite (Ce/MnTiOx/ATP) and cerium-doped MnTiOx/attapulgite (Ce–MnTiOx/ATP) catalysts for low-temperature selective catalytic reduction of nitrogen oxides (NOx) with ammonia (NH3-SCR) were synthesized by co-precipitation methods. The results of catalytic activity testing for the as-prepared Ce–MnTiOx/ATP and Ce/MnTiOx/ATP indicated that the Ce–MnTiOx/ATP catalyst exhibited better catalytic performance with over 80% NOx conversion within a wide temperature window between 170 and 350°, and the highest NOx conversion attained for the Ce–MnTiOx/ATP catalyst was 97.5%. A series of characterization illustrated that the Ce–MnTiOx/ATP catalyst exhibited a higher specific surface area, oxygen vacancy, redox ability, and acid site as compared to that of the Ce/MnTiOx/ATP catalyst. The performance tests showed that the Ce–MnTiOx/ATP catalyst exhibited not only better SO2 & H2O resistance but also higher N2 selectivity and good stability. Therefore, the Ce–MnTiOx/ATP catalyst was testified to be a promising catalyst for NH3-SCR.

A series of γ-MnO2-Ce/MMT catalyst materials synthesized by homogeneous precipitation method was investigated for the selective catalytic reduction (SCR) of NOx with NH3. X-ray diffraction and specific surface areas were utilized for micro structure and layer spacing investigation. And NH3-TPD, Pyridoxine IR, H2-TPR and XPS were used to investigate Brønsted acid and Lewis acid, redox properties, atomic concentrations and element chemical state for as-prepared catalysts. The results showed that the γ-MnO2-Ce/MMT had superior NOx conversion compared to the bulk particles, among which 6 wt.% γ-MnO2-Ce/MMT displayed the best deNOx of 95.3% for the low temperature selective catalytic reduction of NOx with NH3 (NH3-SCR) under the GHSV of 25,000 h−1, therefore it is a promising catalyst for low temperature NH3-SCR.

A flower-like Bi2WO6-Bi2O3 photocatalyst was prepared by a two-step process, including an ionic liquid-assisted solvothermal step and calcination. The effects of the ionic liquids and calcination on the morphology, property, and photocatalytic performance of Bi2WO6-based photocatalysts were studied. The addition of ionic liquids during the preparation of Bi2WO6 based-materials lead to increased sizes of photocatalysts and the formation of more petal sheets in the flower-like microspheres. The results of XRD, XPS, and TEM confirm that Bi2WO6-Bi2O3 photocatalysts formed after the calcination treatment of Bi2WO6 photocatalyst in an air atmosphere. The Bi2WO6-Bi2O3 flower-like photocatalyst exhibits better photocatalytic H2 production activity than the Bi2WO6 photocatalyst. The improved activity of the Bi2WO6-Bi2O3 photocatalysts was attributed to their enhanced light absorption, increased surface area, matched band structure, and the inhibited recombination of the photogenerated charge carriers.

The two-dimensional (2D) metal-organic framework (MOF) [Cd2.25Co0.75(BTB)2(DEF)4]·2(DEF)0.5 (1a, BTB = benzene-1,3,5-tribenzolate; DEF = N,N'-diethylformamide) featuring linear trimetallic cluster secondary building units (SBUs) and replaceable DEF solvates reacts smoothly with dipyridyl ligands DPS, DPDS, and BIPY (DPS = 4,4'-dipyridyl sulfide; DPDS = 4,4'-dipyridyl disulfide; BIPY = 4,4'-bipyridine), yielding three-dimensional (3D) non-interpenetrated [Cd2.25Co0.75(BTB)2(DPS)2]·xSol (2) and [Cd2.25Co0.75(BTB)2(DPDS)2]·xSol (3), and interpenetrated [Cd2.25Co0.75(BTB)2(BIPY)(H2O)2]·xSol (4). The smooth conversion of 1a to 3 contrasts the drastic single-crystal to single-crystal (SCSC) conversion observed for the homometallic [Cd3(BTB)2(DEF)4]·2(DEF)0.5 (1b), presumably due to the presence of the relatively Lewis acidic Co2+ that lessens the propensity for binding by soft dipyridyl donors. Activated samples of 2-4 showed no obvious absorption of N2 at 77 K, but reversible type I uptake of CO2 at 195 K.

Five stable clusters sharing the cuboidal [Ni4O4] skeleton are subjected to third-order nonlinear optical (NLO) property measurements. Preliminary results suggest that the NLO property is largely defined by the cluster core skeleton and the directly coordinated atoms, with limited contribution from the heavy atoms peripherally attached to the aromatic ligands.

Collaborative problem solving (CPS) is considered as one of the core competencies of the 21st century. Collaborative simulations which allow multiple students to participate in CPS activities in a shared simulation session are now increasingly applied to better facilitate these activities. However, the literature has shown that students' collaboration often does not lead to an effective solution to problems. Guided by the PISA CPS framework, this study thus aimed to analyze students collaboration patterns and problem solving strategies in solving a physics problem, and to identify significant patterns which may lead to a successful or unsuccessful outcome. Multiple data sources including group discussions, problem solving activities in a collaborative simulation, and open-ended questionnaire feedback from 30 high school students were analyzed using the lag sequential analysis technique. It was found that collaborative simulation has the potential to help students situate their discussion in a joint concrete problem space, facilitating their formation of a path to solve the problem. More importantly, the results showed significant differences between the successful and unsuccessful groups in terms of their collaboration patterns and problem solving strategies. A considerable portion of the students could only apply an intuitive trial-and-error strategy, and failed to solve the problem in the end. These students showed an inability to monitor and analyze the problem solving process, and were unable to transform their discussion into an executable plan to solve the problem. Those students who applied analytical reasoning strategies were more likely to achieve a successful problem solving outcome. The implications for educational practice are discussed, and the directions for future studies addressed. This study analyzed collaborative problem solving activities in a collaborative simulation context with LSA techniques.Significant differences in collaboration problem solving patterns were detected between successful and unsuccessful groups.A considerable portion of the students showed an inability to monitor and analyze the problem solving process.These students were unable to transform their discussion into an executable plan to solve the problem.Those students who applied analytical reasoning strategies were more likely to achieve a successful problem solving outcome.

Purpose The purpose of this paper is twofold: first, to develop a visualized search system utilizing graphical images to represent the story elements and concepts to help elementary students describe and seek their desired storybooks; and second, to explore the effect of the proposed visualized search system on elementary students’ tactics, success, and motivation for seeking storybooks. Design/methodology/approach A quasi-experimental approach was conducted with a sample of 61 elementary students in this study. The students’ tactics, motivation and the success of their storybook searching were addressed as dependent variables for further comparisons of the visualized searching system and a conventional keyword searching system. Findings The results revealed that the students in the experimental group exhibited more frequent tactics and greater motivation for storybook searching than those in the control group. Further χ2 analysis indicated a significant relationship between the searching interface and the success of the students’ storybook searching. Originality/value This paper proposes a new visual search approach which allows young children to search for storybooks by describing an intended storybook in terms of its characters, objects, or the background colors of the cover page. The findings provide some evidence of the effectiveness of the visualized searching interface in terms of promoting young children’s learning through storybook searching and reading activities.

A facile Pt nanoflowers/nitrogen-doped graphene (PtNFs/NG) electrocatalyst was prepared via depositing Pt nanoflowers (PtNFs) onto the nitrogen-doped graphene (NG) matrix with urea as the nitrogen source and PtNFs/NG modified glassy carbon electrode (GCE) was prepared by electro-chemical method. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Raman spectroscope, X-ray photoelectron spectroscopy (XPS) and Scanning electron microscope (SEM) were used to characterize the resulting composites. Also oxidation of formaldehyde on the resulting PtNFs/NG modified electrode was investigated. The influence of deposition time, electrodeposition potential and formaldehyde concentration on electrooxidation of formaldehyde was detected, the experimental results indicate the high performance of PtNFs/NG catalyst for formaldehyde oxidation is at electrodeposition time of 300 s with the applied potential of −0.3 V. Electrochemical process, electrocatalytic stability and chronoamperometry were also inspected, it was indicated that formalde-hyde oxidation reaction on the PtNFs/NG electrode is diffusion-controlled and PtNFs/NG exhibits a high catalytic activity, stability as well as excellent poisoning-tolerance towards formaldehyde oxidation, which is attributed to the synergistic effect of PtNFs and NG. It turns out that PtNFs/NG can be used in direct liquid-feed fuel cells as a promising alternative catalyst.

IC50 values of Sophoridine for various cancer cells and normal cells. (DOCX 63 kb)

Supplementary Material and Method. (DOCX 46 kb)

Attapulgite/graphene conductive composite is modified by a silane coupling agent of N-(β-aminoethyl)-γ-aminopropyltrimethoxy-silane (KH-792) to make conductive attapulgite uniformly load on the surface of the graphene. The samples are characterized by X-ray diffraction, transmission electron microscopy and Fourier transform infrared spectroscopy. The results demonstrate that the conductive attapulgite is successfully grafted onto the surface of graphene. The characteristics of raw and modified absorbents are characterized by Fourier transform infrared spectroscopy, thermal analysis, scanning electron microscopy and transmission electron microscopy. The results show that the saturated mass fraction of the surface-adsorbed KH-792 silane coupling agent is about 3.0–5.0%. The electrical conductivity and mechanical properties of the conductive coating prepared from the modified conductive composite are investigated. The results show that the surface resistivity of the modified attapulgite/graphene conductive composite coating is smaller than that of the unmodified attapulgite/graphene conductive composite coating when the same amount of is added, and the mechanical properties are also greater than unmodified. As a comparison, when the composite material is 15% mass of the paint which can achieve a best performance.