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Symmetric block copolymers (BCPs) are widely reported as the most effective BCPs for compatibilizing polymer blends via one-pot mixing. However, many BCPs may not be optimally distributed at the interface due to both thermodynamic and kinetic factors. Here, a series of well-defined polybutadiene-b-polyisoprene (PB-b-PI) diblock copolymers with varied block lengths (asymmetric/symmetric) were studied, while a comparable number-average molecular weight (Mn) served as a polymer model system in order to explore the impact of the compositional symmetry of BCPs on compatibilizing PB/PI blends under various kinetic pathways. By a combination of microscopic observation and rheological and mechanical measurements, it is shown that the addition of BCPs in PB/PI blends reduces the dispersed domain size (PB phase) and simultaneously enhances their processability and mechanical performance. Surprisingly, compatibilized blends with asymmetric BCPs could achieve better performance than the blend with symmetric BCPs via sequential mixing. Their properties are even better than the one-pot mixed blend with symmetric BCPs. A mechanism is proposed to explain how these asymmetric BCPs could be more easily distributed at the interface than symmetric ones, thus enhancing the mechanical properties of PB/PI blends. These intriguing results demonstrate that the asymmetric BCP could achieve better compatibilization efficiency than the symmetric BCP by the synergy between molecular symmetry and kinetic pathways.

To investigate the clinical efficacy of surrounding fire needling combined with electroacupuncture (EA) at Jiājĭ (夹脊EX-B2) on acute herpes zoster, and explore the potential mechanism of this combined treatment by measuring the changes of serum inflammatory cytokines and pain mediators.

Many countries and regions across the world have been actively implementing their commitments to achieve carbon neutrality in response to the 2030 Agenda for Sustainable Development and the Paris Agreement on Climate Change (United Nations, 2021). This paper highlights some evolutions and revolutions currently experienced by the transportation industry in different contexts with respect to some common carbon neutrality and environmental sustainability goals. The evolutionary and revolutionary changes are powered by the adoption and implementation of emerging technologies and policies on three aspects: Low-carbon transportation infrastructure, transportation electrification and decarbonization, and intelligent transportation systems management. It is hoped that the experience and lessens we learned from these accumulative and adaptive practices can help us more precisely select and adjust the technological and policy pathways for achieving carbon–neutral transportation.

Many American cities are testing autonomous shuttles (AS), or self-driving minibuses, as a new mode of public transportation. Existing AS studies often rely on stated preference (SP) surveys that require participants to imagine AS scenarios, or they evaluate short-term pilot programs, thus lacking long-term user insights – particularly in car-dependent suburban contexts. To address these limitations, we conducted a revealed preference (RP) study to identify critical factors influencing AS acceptance among users of Move Nona, the longest-running AS network in the United States, located in Lake Nona, a residential suburb in Orlando, Florida. This study expanded the Technology Acceptance Model (TAM) to include six latent factors: perceived ease of use, perceived usefulness, trust in AS safety, perceived AS reliability under inclement weather conditions, personal innovativeness, and environmental awareness. Our findings indicate that perceived usefulness, ease of use, and environmental awareness positively affect AS acceptance. Contrary to previous research, however, trust and personal innovativeness have minimal impact, suggesting that as users become more familiar with AS, they prioritize essential mobility aspects, such as travel speed and convenience, over technological novelty. These insights are valuable for decision-makers planning to adopt AS to enhance local transit services, while also contributing to the broader field of behavior analysis by corroborating an extended application of TAM in examining AS user acceptance.

Inspired by the mechanism of the clock reaction, we rationally constructed a novel phosphomolybdenum blue (PMB) clock catalytic system for a highly efficient synthesis of benzimidazoles and benzothiazoles simply at ambient temperature. The current PMB clock catalytic system exhibits a sharp decoloration event to announce the depletion of the intermediateconstraint, making this synthetic approach self‐indicating and TLC‐free.31P NMR and XPS analysis of PMBcatalyst showed that only two Mo6+atoms are reduced to Mo5+atoms in the Keggin structure due to the moderate reducibility of benzimidazoline and benzothiazoline intermediates. Thus,the active Keggin‐type POM cluster could be well maintained in DMSO during the redox cycling of phosphomolybdic acid (PMA) and PMB. 1H NMR tracing experiment not only confirmed the proposed reaction mechanism but also showed that PMB exerts Lewis acid catalytic activityat the early phase of the reaction other than the expected redox catalytic activity. A novel phosphomolybdenum blue (PMB)clock catalytic system has been constructed featuring highly efficient synthesis of benzimidazoles and benzothiazoles at ambient temperature and color‐based reaction process self‐indication. 31P NMR and XPS analysis of PMB catalyst and 1H NMR tracing of the reaction process provided more insights into the working mechanism of PMB clock catalytic system.

In port areas, traffic is characterized by container trucks which run on diesel, while in urban areas it is characterized by private cars which run on petrol. The different fuels as pollution sources cause distinct particle pollution. This study offers an in-depth investigation of particle pollution and corresponding short-term exposures in port and urban areas. Field measurements were carried out to collect the data including particulate matter and traffic volume. Based on the data, firstly, the Pearson correlation analysis was performed to analyze the relationships between traffic volume and particles. Secondly, the Anderson–Darling test was adopted to identify the “best-fit” distributions on particles. Thirdly, comparisons of particle pollution levels in port and urban areas were analyzed. Finally, the pedestrian respiratory deposition doses of particles were estimated. The results indicate the importance and urgency of reducing air pollution, especially for port cities, and provide policymakers with a foundation for possible measures in the port city.

We report a poly(norbornene-graft-styrene) (PNB-g-PS) supported mono(phenoxy–imine) metal complex for ethylene polymerization. As a molecular bottlebrush (MB), PNB-g-PS was prepared via grafting-through ring-opening metathesis polymerization (ROMP) of the norbornenyl macromonomer. Postmodification reactions of PNB-g-PS were performed to incorporate phenoxy–imine type ligands in PS side chains, which were then coordinated with early transition metals to generate a series of MB supported mono(phenoxy–imine) catalysts. The loading efficiency of the metals was assessed by inductively coupled plasma mass spectrometry. Using these catalysts with four types of phenoxy–imine ligands and two metals (Ti and Zr), we evaluate their catalytic performances (activity, Mw, and the crystallinity of polyethylenes) for ethylene polymerization. Improved catalytic activities were observed for the catalysts bearing bulky substituents orthoto the phenolic oxygen in the ligands. The highest ones are 369 and 461 kg PE mol–1h–1for the Ti and Zr catalysts with a cumyl group. The obtained polyethylenes (PEs) have high crystallinities and tunable molecular weights ranging from 80 to 2000 kDa. We also successfully prepared bimodal PEs in one pot by rationally combining two different phenoxy–imine ligands in the MB supported catalysts.

As Volatile Organic Compounds (VOCs) are one of the precursors of ozone, their distribution and variable concentrations are highly related to local ozone pollution control. In this study, we obtained vertical profiles of VOCs in Shanghai’s Jinshan district on 8 September and 9 September in 2016 to investigate their distribution and impact on local atmospheric oxidation in the near surface layer. Vertical samples were collected from heights between 50 m and 400 m by summa canisters using an unmanned aerial vehicle (UAV). Concentrations of VOCs (VOCs refers to the 52 species measured in this study) varied minimally below 200 m, and decreased by 21.2% from 100 m to 400 m. The concentrations of VOCs above 200 m decreased significantly in comparison to those below 200 m. The proportions of alkanes and aromatics increased from 55.2% and 30.5% to 57.3% and 33.0%, respectively. Additionally, the proportion of alkenes decreased from 13.2% to 8.4%. Toluene and m/p-xylene were the key species in the formation of SOA and ozone. Principal component analysis (PCA) revealed that the VOCs measured in this study mainly originated from industrial emissions.

It is challenging to forecast high-resolution spatial-temporal patterns of intra-urban air pollution and identify impacting factors at the regional scale. Studies have attempted to capture features of air pollutants such as fine particulate matter (PM2.5) and nitrogen dioxide (NO2) using land use regression models, but this method overlooks the multi-collinearity of factors, non-linear correlations between factors and air pollutants, and it fails to perform well when processing daily data. However, machine learning is a feasible approach for establishing persuasive intra-urban air pollution daily variation models. In this article, random forest is utilised to establish intra-urban PM2.5and NO2spatial-temporal variation models and is compared to the traditional land use regression method. Taking the city of Shanghai, China as the case area, 36 station-measured daily records in two and a half years of PM2.5and NO2concentrations were collected. And over 80 different predictors associated with meteorological and geographical conditions, transportation, community population density, land use and points of interest are used to construct the land use regression and random forest models. Results from the two methods are compared and impacting factors identified. Explained variance (R2) is used to quantify and compare model performance. The final land use regression model explains 49.3% and 42.2% of the spatial variation in ambient PM2.5and NO2, respectively, whereas the random forest model explains 78.1% and 60.5% of the variance. Regression mappings for unsampled sites on a grid pattern of 1 km × 1 km are also implemented. The random forest model is shown to perform much better than the land use regression model. In general, the findings suggest that the random forest approach offers a robust improvement in predicting performance compared to the land use regression model in estimating daily spatial variations in ambient PM2.5and NO2.

Using acyclic diene metathesis (ADMET) polymerization, we have synthesized a series of random conjugated copolymers from diene monomers based on tetraphenylethene (TPE), which is an aggregation-induced emission (AIE)-active molecule, and comonomers such as 1,9-decadiene, 2,7-divinyl-9,9-di-n-octylfluorene, and 1,4-dihexyl-2,5-divinylbenzene. These all-hydrocarbon copolymers exhibit good solubility and high molecular weights. As proved by 1H NMR spectra, chain segments composed of two monomers are randomly distributed in the polymers. Absorption and emission features from both TPE units and those conventional diene segments in conjugated copolymers are observed in their optical spectra. Because of the presence of AIE-active TPE units, emission intensities of the copolymers are greatly enhanced in tetrahydrofuran/water mixtures with increased water content. Moreover, the fluorescence of ADMET polymers can be quenched by palladium ions in quasi-aqueous solutions following a dynamic quenching mechanism. The fluorescence quench degrees are affected by both chemical structures of the copolymers and the solvent polarity. Our findings demonstrate that ADMET conjugated polymers have enormous potential as fluorescent “turn-off” probes specific for palladium ions even in the absence of a particular coordination interaction.

As a common clinical syndrome, voiding dysfunction is complicated in etiology, involved in a variety of diseases and associated with multi-disciplines of medicine. Either medication or surgery has not obtained the favorable effect on it. Integrated the theories of traditional Chinese medicine and Western medicine and based on the pathogenesis of the disease, the acupoint specificity and neuromodulatory effects, Professor Wei-bin GAO suggested “selecting the acupoints along the affected areas”. The acupoints located near to the lumbar, sacral and abdominal regions are dominated and stimulated with electroacupuncture at different electric waves. In treatment, electric stimulation with disperse and dense waves was adopted. The bone conduction theory of dense-wave electric field was proposed. The same neuromodulation is presented in different diseases such as neurogenic bladder, pediatric enuresis, senile nocturia, benign prostatic hyerplasia, and postpartum of postoperative urination disorders. Hence, the same therapeutic method is adoptable to different diseases with the basic acupoint composition modified.

Chain shuttling polymerization is a powerful approach for efficiently producing olefin block copolymers via simple one-pot polymerization. Herein, this method was used to synthesize ethylene-norbornene cycloolefin block copolymers (COBCs). Two bis(salicylaldiminato)titanium complexes with different monomer selectivities were used to generate alternating hard and soft blocks of high and low norbornene incorporation, respectively, in the presence of chain shuttling agents (diethyl zinc). The high glass transition temperature (Tg) of the hard blocks contributed to their high tensile strength, while the low Tgof the soft blocks led to their high ductility. By varying the concentration of norbornene during the copolymerization process, it is possible to tune the Tgvalues of the hard and soft blocks, thus achieving a transition in the mechanical properties of the COBCs from typical elastomers to plastics while maintaining high ductility and transparency. Compared with random cycloolefin copolymer plastics, the COBC in this study exhibited a 55-fold increase in elongation at break and maintained comparable tensile strength. This study highlights the development of a new class of chain shuttling catalytic systems to produce COBCs with widely tunable Tgvalues to modulate their mechanical properties.

With increasing numbers of motor vehicles, vehicle exhaust gas has become one of the most important sources of urban air pollutants. After being emitted from the motor vehicle, exhaust gas spreads through the air along the road and is gradually deposited in the surrounding area, having an adverse impact on pedestrians and residents. At present, most research on vehicle exhaust directly measures the total emissions from the exhaust pipe or monitors the time variation of air pollutants at the roadside by setting roadside monitoring stations. The spatial resolution of these two methods is very low, however, and it is impossible to describe accurately the diffusion patterns of exhaust gas in the atmosphere after discharge. Some scholars have conducted research on the quality of roadside air by hand-held portable devices, but these are limited by the speed of travel, and the spatial and temporal resolution of the acquired data is also very low. By using multi-rotor unmanned aerial vehicles (UAVs) and portable equipment, this study demonstrates an atmospheric environment monitoring system based on multi-rotor UAV by designing corresponding hardware circuits and software programs. With flexible requirements for takeoff or landing sites and high maneuverability of multi-rotor UAVs, the system increases the capability for high resolution spatial and temporal monitoring of the diffusion of traffic-emitted pollutants. The system can conduct fixed-point measurement by hovering, and can also measure air pollutants in complex urban terrain, providing an innovation in the study of vehicle exhaust gas diffusion.

To observe the clinical efficacy of fire-needle therapy in treating deglutition disorders due to pseudobulbar palsy in the remission stage of stroke. Sixty-two eligible subjects were divided into a fire-needle group and a rehabilitation group by a simple randomization method at a ratio of 1:1. The two groups received same basic intervention; in addition, the fire-needle group received fire-needle treatment, while the rehabilitation group received rehabilitation training. The two groups of subjects all received a 3-week treatment and were evaluated by the dysphagia severity rating scale (DSRS), modified Mann assessment of swallow ability (MMASA) and Kubota Toshio swallow test (KTST) before and after the intervention. The complications and adverse events occurred during the trial were recorded. The data were statistically analyzed. At the third week, the DSRS, MMASA and KTST scores changed significantly compared with the baseline in both groups (P<0.05), and the changes in the fire-needle group were more significant than those in the rehabilitation group (P<0.05). The between-group comparison at the third week showed that the therapeutic efficacy in the fireneedle group was superior to that in the rehabilitation group (P<0.05). Fire-needle therapy can obviously change the DSRS, MMASA and KTST scores in pseudobulbar palsy in the remission stage of stroke, and significantly enhance the therapeutic efficacy of the treatment of deglutition disorders in this stage. 观察火针治疗卒中恢复期假性延髓麻痹吞咽困难的临床疗效。 将符合纳入标准的62例受试者按1:1比例采用简单随机法分为火针组和康复组。两组接受相同的基础治疗, 火针组加用火针治疗, 康复组加用 康复训练。两组受试者均治疗3周, 分别在治疗前、治疗后进行吞咽严重程度量表(DSRS)、改良版Mann吞咽量表 (MMASA)和洼田俊夫饮水测试(KTST)三个量表的评价, 并对实验过程中的并发症、不良反应等进行记录, 最后对研究数据进行统计学分析。 在第3周, 两组DSRS、MMASA和KTST与治疗前比较有显著改变(P<0.05), 且火针组与康复组比较差异显著(P<0.05)。在第3周时两组间疗效比较, 火针组疗效均优于康复组(P<0.05)。 火针可以显著改变卒中恢复期假性延髓麻痹的DSRS、MMASA和KTST评分, 显著提高卒中恢复期假性延髓麻痹吞咽困难的疗效。

Mitigating carbon emission efforts in urban planning and design phase have become increasingly popular due to climate change. However, it is difficult to verify whether the carbon mitigation target could be achieved for a new city in the absence of quantitative analysis methods. About 100 new cities have emerged every year in the past decades, yet few of them employed low carbon strategies within proper prediction methods. In response, this paper offers an integrated analysis method of assessment and mitigation for urban carbon dioxide (CO2) of new cities. Building sector, transportation sector, and green land sector are considered as urban CO2sources and sink. Life cycle analysis was employed in building sector to estimate its emissions. Based on the current and predicted emission data, a mitigation goal was then set and allocated efficiently through different sectors. To elaborate on this process, a case study of Shanghai Lingang New City was presented. The urban low carbon roadmap was planned and a variety of recommendations concerning policy were offered to assist the local government and policy makers in order to achieve the low carbon development goal as well.

The potato tuberworm Phthorimaea operculellaZeller, is one of the most important potato pests worldwide including China. Several reports indicate that P. operculellacould be controlled biologically by the use of beneficial fungus such as Beauveria bassiana(Bals.-Criv) Vuill. However, limited information is available under growing conditions in China. Thus, this study evaluated the sub-lethal effects of B. bassianaon the offspring of P. operculellaby the age-stage, two-sex life table. First instar larva of P. operculellawere treated with 1×107conidia mL−1of the fungus, and several biological parameters were evaluated. The fecundity, duration of the egg stage, all larval stages, pre-adult stage, and total pre-oviposition period, were significantly shorter than the control treatment. Offspring of treated parents, presented a net reproductive rate and mean generation time of 17.43 per day and 24.98 days, respectively, compared to 65.79 per day and 26.51 days for the untreated ones. This study provides basic information to help understanding the potential long-term effects of entomopathogenic fungi on P. operculella.

Transportation-related risk factors are a major source of morbidity and mortality in China, where the expansion of road networks and surges in personal vehicle ownership are having profound effects on public health. Road traffic injuries and fatalities have increased alongside increased use of motorised transport in China, and accident injury risk is aggravated by inadequate emergency response systems and trauma care. National air quality standards and emission control technologies are having a positive effect on air quality, but persistent air pollution is increasingly attributable to a growing and outdated vehicle fleet and to famously congested roads. Urban design favours motorised transport, and physical activity and its associated health benefits are hindered by poor urban infrastructure. Transport emissions of greenhouse gases contribute substantially to regional and global climate change, which compound public health risks from multiple factors. Despite these complex challenges, technological advances and innovations in planning and policy stand to make China a leader in sustainable, healthy transportation.

In China, the roles played by high speed rail (HSR) in improving regional accessibility and promoting urban growth have recently generated significant research interest. However, the question as to how HSR could shape urban development seems rather complex. This paper aims to discuss HSR’s role in shaping urban economic development by tracing links from HSR to manufacturing agglomeration with panel data from the Beijing–Guangzhou HSR network in China from 2000 to 2015. On the basis of the new economic geography model, market potential and manufacturing wages are incorporated into the analysis framework, and a treatment effect model is used to account for the endogeneity of HSR in the study. Model results provide three conclusions. First, in general, HSR significantly increases manufacturing agglomeration for HSR cities. Second, an inverted-U relationship between the agglomeration impact of HSR and market potential is confirmed. That is, while the agglomeration effect by HSR is significantly within a threshold level of market potential, HSR in fact has a negative effect, or the dispersion effect, on manufacturing agglomeration beyond the threshold level. Third, the agglomeration impact of HSR differs across regions. For example, the agglomeration impact of HSR is more significant in the second-tier HSR cities than in major HSR cities, indicating the overall trend of regional integration and economic convergence among different regions of HSR through time. Results from this study are useful for policy makers as well as for researchers for analyzing the economic implications of HSR in the future.

PBO fiber is a kind of super fibers which has both high tension strength and high modulus. After the heat-treatment procedure, the PBO fiber would present more perfect mechanical properties. The process route of heat-treatment on as-spun fibers (PBO-AS fibers) was optimized, and the obtained high modulus fibers (PBO-HM fibers) were tested and characterized by SEM, XRD, XPS, FT-IR and Universal material machine. The higher the temperature is, the shorter the heat treatment time required for the same heat treatment. And the most preferred procedure in the air atmosphere of heat-treatment was 550°C with the resident time of 32 s and the pre-stress of 2.35 cN/dtex. After the heat-treatment, the modulus of PBO-HM grew up to 229.4 GPa (1487.78 cN/dtex). The tensile strength would not be greatly decreased, if the fiber could be kept in the nitrogen atmosphere. Besides, the XRD data and the XPS data proved that after the heat-treatment, the crystal size and the crystallinity would have a huge growth and the content of phosphorus element on the surface of PBO-HM fibers would fall sharply.

To replace metal padding by insulation padding for castings can save the melt and reduce cleaning work of castings. The design of insulation padding was investigated. The equation of the modulus extension factor for insulation padding and the ratio of its thickness over the modulus of a casting were improved to determine the thickness of insulation padding. The insulation padding was designed for a turbine guide vane casting weighing 3. 5 t. A sound casting was obtained with 750 kg steel saved. On the other side, the casting obviously expanded at the interface with the insulation padding, which is perhaps the reason that the use of insulation padding has been suspended for many years. To avoid the expansion of insulation padding, a shielding layer made of a kind of material of good fire resistance was adopted to prevent the insulation layer from touching the melt. The shielding layer serves as a cushion of heat and expansion during solidification process so as to resist the expansion of castings and guarantee the feeding effect at the same time. Furthermore, insulation padding can be placed by a certain offset into the mold cavity so as to counteract the expansion of castings.

To replace metal padding by insulation padding for castings can save the melt and reduce cleaning work of castings. The design of insulation padding was investigated. The equation of the modulus extension factor for insulation padding and the ratio of its thickness over the modulus of a casting were improved to determine the thickness of insulation padding. The insulation padding was designed for a turbine guide vane casting weighing 3.5 t. A sound casting was obtained with 750 kg steel saved. On the other side, the casting obviously expanded at the interface with the insulation padding, which is perhaps the reason that the use of insulation padding has been suspended for many years. To avoid the expansion of insulation padding, a shielding layer made of a kind of material of good fire resistance was adopted to prevent the insulation layer from touching the melt. The shielding layer serves as a cushion of heat and expansion during solidification process so as to resist the expansion of castings and guarantee the feeding effect at the same time. Furthermore, insulation padding can be placed by a certain offset into the mold cavity so as to counteract the expansion of castings.

Using the material testing machine of electro-hydraulic servo fatigue tests had been carried out on ordinary concrete and steel fiber reinforced concrete. The fatigue life, strength, stress and strain had been measured under tension and compression loading. The variation of fatigue was analyzed based on the test results. Having regression analysis, obtained the fatigue strength. Mean-while, the fatigue strain-life curves of ordinary concrete and steel fiber reinforced concrete had been made after data processing. The results had been showed that the fatigue property of steel fiber reinforced concrete was significantly higher than that of ordinary concrete. And the fatigue strength increased about 32.6% compared with ordinary concrete. The tensile and compressive fatigue strain were slightly smaller than that of ordinary concrete.

Patterned porous surfaces with responsive functionalities are fabricated by a thermoresponsive microgel-assisted breath figure (BF) process. When water droplets submerge into a polystyrene (PS) solution during formation of a porous surface by the bottom-up BF process, poly(N-isopropylacrylamide)-co-acrylic acid (PNIPAm-co-AA) microgels dispersed in the solution spontaneously assemble at the water–organic interfaces like “Pickering emulsions”, reinforced by capillary flow. The conformal layer of PNIPAm-co-AA microgels lining the pores appears in images from a scanning electron microscope (SEM) either as a smooth surface layer (L) or as an array of domelike protrusions (D), depending on the conditions at which the sample was dried for SEM. The change between L and D morphology correlates with the volume phase transition behavior of the microgels freely suspended: drying at a temperature below the volume phase transition temperature (VPTT) gives L, and the D morphology is formed by drying at a temperature greater than the VPTT of PNIPAm-co-AA microgels. The morphological transition is shown to accompany a significant change in surface contact angle (CA) relative to a corresponding pore layer made of PS, with L having a CA that is reduced by 85° relative to PS, while the decrease is only 22° for D. Porous structures with morphologically responsive surfaces could find application in biocatalysis or tissue engineering, for example, with functional enzymes sequestered when microgels are collaped and accessible when the microgels are swollen.

In China, the roles played by high speed rail (HSR) in improving regional accessibility and promoting urban growth have recently generated significant research interest. However, the question as to how HSR could shape urban development seems rather complex. This paper aims to discuss HSR's role in shaping urban economic development by tracing links from HSR to manufacturing agglomeration with panel data from the Beijing–Guangzhou HSR network in China from 2000 to 2015. On the basis of the new economic geography model, market potential and manufacturing wages are incorporated into the analysis framework, and a treatment effect model is used to account for the endogeneity of HSR in the study. Model results provide three conclusions. First, in general, HSR significantly increases manufacturing agglomeration for HSR cities. Second, an inverted-U relationship between the agglomeration impact of HSR and market potential is confirmed. That is, while the agglomeration effect by HSR is significantly within a threshold level of market potential, HSR in fact has a negative effect, or the dispersion effect, on manufacturing agglomeration beyond the threshold level. Third, the agglomeration impact of HSR differs across regions. For example, the agglomeration impact of HSR is more significant in the second-tier HSR cities than in major HSR cities, indicating the overall trend of regional integration and economic convergence among different regions of HSR through time. Results from this study are useful for policy makers as well as for researchers for analyzing the economic implications of HSR in the future.

As an important class of nucleoside triphosphate analogues, α‐P‐modified nucleoside triphosphates (NTPαXs) have long been recognized as versatile tools in molecular biology and medicinal chemistry. However, the available synthetic methods based on modified nucleoside monophosphate and cyclic PVPVPIII‐nucleoside intermediates are only low to moderate‐yielding. Inspired by recent progress on PV‐PIIIcoupling reactions, we attempted to access NTPαXs via the putative linear PVPVPIII‐nucleoside intermediates. The current research found that a specific type of nucleoside phosphoramidites, fluorenylmethyl (Fm) nucleosidyl‐phosphoromorpholidites, are highly reactive in coupling with nBu4NH3P2O7even without acidic activators. In situoxidation of linear PVPVPIII‐nucleosides with specific sulfurizing, boranylating, and selenylating reagents followed by deprotection of α‐Pand nucleoside moieties afforded NTPαXs (X=S, Se, and BH3) in excellent isolated yields. By exploiting dicyanoimidazole (DCI)’s promoting effect on PV‐PIIIcoupling, the current linear PVPVPIII‐nucleoside‐based method was further developed into an efficient route to α‐P‐modified dinucleoside tetraphosphates. A novel and efficientmethod for synthesis of α‐P‐modified nucleoside triphosphates and dinucleoside tetraphosphates via linear PVPVPIII‐nucleoside intermediates has been developed.

The western flower thrips, Frankliniella occidentalis,is one of the most destructive sucking pests of vegetables, fruits and ornamental crops in China. Spinosad is one of the most commonly used insecticides to manage thrips. To assess the incidence of spinosad resistance in F. occidentalisfield populations in eastern China, survival rates for 24 different populations were compared with those of a susceptible laboratory strain. All populations showed significantly higher resistance to spinosad compared with the control as determined by comparing median lethal concentrations. Two populations from Shouguang and Liaocheng in Shandong Province were classified as having moderate and high levels of resistance to spinosad with a mean resistance ratio of 17.0 and 89.2, respectively. Our research indicates a widespread reduction in spinosad efficacy for controlling F. occidentalisfield populations, and that resistance management strategies should be implemented as soon as practicable, to reduce the potential of progressive resistance development and loss of efficacy.