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Abstract Aiming at the problem of increased water injection pressure and poor water injection effect during the water injection operation of Weizhou X offshore low permeability oil reservoir. The cause of clogging was clarified using cast thin section experiments, water quality compatibility experiments and reservoir sensitivity experiments, and corresponding deblocking agents were configured based on the experimental results. The experimental results show that Weizhou X oilfield has strong velocity sensitivity (damage rate 85.35%) and strong salt sensitivity (damage rate 63.02%), and there is a phenomenon of water quality incompatibility. Analysis shows that the excessive velocity of the injected water causes the core particles to fall off and the water quality is incompatible with the calcium carbonate precipitation to cause pore throat blockage as the fluid migrates to the small roar, which is the main reason for the increase in water injection pressure. Based on the analysis results, the acid solution formula was optimized and determined to be: 12% HCl + 0.5% HF + 3% CH3COOH + 0.5% C6H12N4. Indoor test results show that the acid has good clay swelling prevention and reservoir modification effects, and the average reservoir modification rate is 129.21%. The plug‐removing effect is remarkable and can be promoted in similar oil fields.

Societal Impact Statement Advancements in science and technology enable us to address the challenges of the times: hunger, malnutrition, climate change, and dwindling natural resources. One of the most significant innovations in food and agriculture is the advent of genetic engineering, which may help us address the aforementioned challenges. Millions of people could benefit from the application of genetically engineered crops in agriculture and food. However, it is vital that biosafety assessments of unintended effects are carried out to identify any potential risks to humans, the environment, or society. Summary The study compared the extent of siRNA, transcriptomic and metabolomic changes in the leaves of four RNAi‐based genetically engineered rice lines to evaluate whether RNAi‐based genetically engineered rice that is resistant to black‐streaked dwarf virus experiences changes not seen in the non‐genetically engineered counterpart. siRNA, transcriptome, and metabolome profiling were conducted. siRNAs with different lengths and abundance were highly enriched in the transcript of rice; however, relative expression analysis of eight potential off‐target genes revealed that there was no decrease in gene expression in the RNAi‐based genetically engineered lines, meaning that no off‐target phenomena were caused as a result of siRNA derived from invert repeat sequences of rice black‐streaked dwarf virus in this study. This study identified some differentially expressed genes and differentially accumulated metabolites in the RNAi‐based genetically engineered lines; however, they were not enriched in pathways detrimental for humans, animals and the environment. Only 30 differentially expressed genes were significantly enriched in the plant hormone signal transduction pathway via a combined analysis using two‐way orthogonal partial least squares model. These genes belonging to salicylic acid, jasmonic acid, cytokinin, abscisic acid, and brassinosteroid pathway involved in pathways related to virus resistance or infection response were significantly changed. Taken together, there was no off‐target in RNAi‐based genetically engineered rice lines and may have a positive effect on virus resistance overall in this study.

Shared parking enables private parking owners to share their parking spaces during idle time. In recent years, increasingly more research investigated people’s intentions to participate in shared parking schemes as well as optimization algorithms to match shared parking supplies and demands. However, little research has investigated the distribution of shared parking use in time and space in implementation. To fill this gap, this study uses the transaction records of 121 shared parking lots in Guangzhou, China, and applies a quasi-Poisson regression model to analyze the influence of a set of explanatory factors on the total number of transactions. The results show that the number of parking transactions is significantly influenced by implemented duration, parking lot capacity, land use of shared facility, number of POIs (point of interest), and transit stations within a range of 750 meters from the shared parking lot. This study also applies a linear regression model to analyze the effect of a set of explanatory variables on the average parking duration at shared parking lots. The results show that the average parking duration is significantly influenced by the land use of a shared facility, number of office buildings within 750 meters from the shared parking lot, and peak time of the shared parking lots.

The pandemic has brought about various changes, such as work-from-home or telecommuting, and an increase in online shopping for day-to-day necessities. These changes have had a sizeable impact on commercial real estate businesses and, to a varying degree, on the fiscal base of local governments, especially in large cities. As the world settles into the post-pandemic era, flexible working arrangements such as remote work, hybrid work, and telecommuting are expected to become the new normal. As a result, large and small corporates have been reviewing policies on remote working. Some of them have either dialled back their office expansion plans or have shown preference for premium office spaces. This move is expected to weigh on tax revenue collections from property rentals for cities. Also, revenue from transportation services and restaurant businesses would decline. Hence, local governments would have to redesign their fiscal policies and invest in new opportunities, such as creating recreational facilities and converting old office structures into residential buildings. This paper uses available literature, media references, and industry and government reports to identify the potential impact of changing work arrangements on the office market in Hong Kong, New York, and London. We further attempt to understand the impact of this transition on the fiscal base of cities and the actions that policymakers can take to mitigate and adapt to this new economic situation.

In the context of land relocation, poverty alleviation resettlement (PAR) is considered an effective approach to improve the man–land relationship and development issues. However, current studies pay little attention to PAR and its spillover effects within developed regions. Furthermore, the complete mechanism chain has received little research concentration. Thus, employing a qualitative survey, this study aims to investigate the overall mechanisms of developed regions’ PAR in the context of land relocation. The study will deal with the following questions: Why does PAR occur in developed regions? How does the resettlement approach to poverty alleviation (i.e., paths)? What are the effects of resettlement on poverty alleviation, including its own effects and spillover effects? Through answering these questions, this study will highlight PAR in developed regions and investigate the spillovers from social, economic and ecological perspectives. Particularly, a comprehensive mechanism analysis framework for PAR will be presented to motivate future studies. Results indicate that PAR is generally caused by ecological poverty alleviation, geological disaster prevention and county town urbanisation promotion and that emigration and resettlement are the paths to PAR. In addition, the direct outcome is the overall rise in the number of resettlers over time, and the spillovers show the sustainable collaboration of economic, social and ecological dimensions. These findings will influence future land reform and housing initiatives.

With the improvement of people’s living standard, the number of patients with thromboembolism is increasing gradually. Among the existing thrombotic drugs, nattokinase attracts great attention due to its advantages of long half-life, strong specificity, small side effects, and can be taken orally directly. Based on the related research results at home and abroad, the structure features of nattokinase, the fibrinolytic activity and the mechanism of action of antithrombotic activity of NK are described. Also, the hard work in strain breeding, strain transformation for higher enzyme yield or better enzyme character and medium optimization are also summarized. Moreover, the physiological function of nattokinase are expounded. Finally, the challenges and future development trends of nattokinase application are prospected in order to provide theoretical basis for further research on nattokinase.

Abstract This study evaluates the effectiveness of Hong Kong’s strict border restrictions with mainland China in curbing the transmission of COVID-19. Combining big data from Baidu Population Migration with traditional meteorological data and census data for over 200 Chinese cities, we utilize an advanced quantitative approach, namely synthetic control modeling, to produce a counterfactual “synthetic Hong Kong” without a strict border restriction policy. We then simulate infection trends under the hypothetical scenarios and compare them to actual infection numbers. Our counterfactual synthetic control model demonstrates a lower number of COVID-19 infections than the actual scenario, where strict border restrictions with mainland China were implemented from February 8 to March 6, 2020. Moreover, the second synthetic control model, which assumes a border reopen on 7 May 2020 demonstrates nonpositive effects of extending the border restriction policy on preventing and controlling infections. We conclude that the border restriction policy and its further extension may not be useful in containing the spread of COVID-19 when the virus is already circulating in the local community. Given the substantial economic and social costs, and as precautionary measures against COVID-19 becomes the new normal, countries can consider reopening borders with neighbors who have COVID-19 under control. Governments also need to closely monitor the changing epidemic situations in other countries in order to make prompt and sensible amendments to their border restriction policies.

Mass gatherings provide conditions for the transmission of infectious diseases and pose complex challenges to public health. Faced with the COVID-19 pandemic, governments and health experts called for suspension of gatherings in order to reduce social contact via which virus is transmitted. However, few studies have investigated the contribution of mass gatherings to COVID-19 transmission in local communities. In Hong Kong, the coincidence of the relaxation of group gathering restrictions with demonstrations against the National Security Law in mid-2020 raised concerns about the safety of mass gatherings under the pandemic. Therefore, this study examines the impacts of mass gatherings on the local transmission of COVID-19 and evaluates the importance of social distancing policies. With an aggregated dataset of epidemiological, city-level meteorological and socioeconomic data, a Synthetic Control Method (SCM) is used for constructing a ‘synthetic Hong Kong’ from over 200 Chinese cities. This counterfactual control unit is used to simulate COVID-19 infection patterns (i.e., the number of total cases and daily new cases) in the absence of mass gatherings. Comparing the hypothetical trends and the actual ones, our results indicate that the infection rate observed in Hong Kong is substantially higher than that in the counterfactual control unit (2.63% vs. 0.07%). As estimated, mass gatherings increased the number of new infections by 62 cases (or 87.58% of total new cases) over the 10–day period and by 737 cases (or 97.23%) over the 30-day period. These findings suggest the necessity of tightening social distancing policies, especially the prohibition on group gathering regulation (POGGR), to prevent and control COVID-19 outbreaks.

Weizhou 11-4N oilfield is a medium-low-porosity and low-permeability reservoir. The oilfield was initially developed by edge and bottom water energy and then transferred to water injection development. Affected by poor physical properties and heterogeneity of the reservoir, the oilfield appeared in the process of water injection development. When the water injection pressure increases, the water injection volume continues to decrease, and it is difficult to meet the injection requirements. On the basis of the analysis of reservoir heterogeneity, void structure, and clay minerals of reservoir, the water injection compatibility experiment, damage evaluation experiment, and nuclear magnetic resonance-velocity sensitivity experiments were carried out to clarify the damage in the process of oilfield water flooding development. Experiments show that the main causes of damage in Weizhou 11-4N oilfield water flooding development process are water quality incompatibility and strong velocity-sensitive damage. The determination of water type shows that the injected water and formation water are MgCl2 water type and NaHCO3 water type, respectively, under the classification of Surin water type, resulting in the formation of scale with calcium carbonate as the main component in the reservoir. Incompatibility of water quality is an important cause of reservoir damage and scaling. In the reservoir-sensitive flow experiment, the experimental core showed strong velocity sensitivity, the average velocity sensitivity damage rate was 466.31%, and the average critical velocity was 2.98 m/d. Nuclear magnetic resonance experiments show that the core has a significant decrease in average pore size after water flooding. The main damage range is the tiny throat of 0-2 μm. In this paper, the main damage interval of velocity-sensitive damage in the Weizhou 11-4N area and the change trend of void structure after velocity-sensitive experiment are clarified by nuclear magnetic resonance and velocity sensitivity experiments. The main cause of block reservoir damage provides the basis for the oilfield to take targeted measures and provides a guarantee for the efficient development of the subsequent oilfield.

Fault diagnosis is one of the most challenging tasks in power communication.The fault diagnosis based on rules can no longer meet the demand of massive alarms processing.The existing approaches based on the supervised learning need large sets of the labeled data and sufficient time to train models for processing continuous data instead of alarms, which are far behind the feasibility of deployment.As for alarm correlation and fault pattern discovery, a self-learning algorithm based on the density-based clustering and frequent subgraph mining was proposed.A novel approach for automatic fault diagnosis and dispatch were also introduced, which provided the scalable and self-renewing ability and had been deployed to the automatic fault dispatch system.Experiments in the real-world datasets authorized the effectiveness for timely fault discovery and targeted fault dispatch.

Abstract Genetic engineering (GM) has great potential to improve maize productivity, but rises some concerns on unintended effects, and equivalent as their comparators. There are some limitations through targeted analysis to detect the UE in genetically modified organisms in many previous studies. We here reported a case-study on the effects of introducing herbicides and insect resistance (HIR) gene cassette on molecular profiling (transcripts and metabolites) in a popular maize variety Zhengdan958 (ZD958) in China. We found that introducing HIR gene cassette bring a limited numbers of differential abundant genes (DAGs) or differential abundant metabolites (DAMs) between transgenic events and non-transgenic control. In contrast, averaged 10 times more DAGs and DAMs were observed when performed comparison under different growing environments in three different ecological regions of China than the numbers induced by gene effects. Major biological pathways relating to stress response or signaling transduction could explain somehow the effects of growing environments. We further compared two transgenic events mediated ZD958 (GM-ZD958) with either transgenic parent GM-Z58, and other genetic background nonGM-Z58, nonGM-ZD958, and Chang7-2. We found that the numbers of DAGs and DAMs between GM-ZD958 and its one parent maize variety, Z58 or GM-Z58 is equivalent, but not Chang7-2. These findings suggest that greater effects due to different genetic background on altered molecular profiling than gene modification itself. This study provides a case evidence indicating marginal effects of gene pleiotropic effects, and environmental effects should be emphasized.

In this work, Arg-Gly-Asp (RGD) peptide-coupled polydopamine-modified mesoporous platinum nanoparticles (mPt@PDA-RGD NPs) were developed for targeted photothermal therapy (PTT) and migration inhibition of SKOV-3 cells. mPt@PDA-RGD NPs with obvious core/shell structure demonstrated high photothermal performance under 808-nm near-infrared (NIR) laser irradiation. mPt@PDA-RGD NPs with favorable biocompatibility exhibited remarkable SKOV-3 inhibition ability under NIR laser irradiation. Moreover, compared to mPt@PDA NPs, the RGD-functionalized NPs achieved more tumor uptake and PTT performance, which was attributed to the specific interaction between RGD of NPs and αvβ3 integrin overexpressed by SKOV-3. Importantly, cell scratch experiments indicated that the photothermal effect of mPt@PDA-RGD NPs can effectively inhibit the migration of surviving SKOV-3 cells, which was assigned to disturbance of the actin cytoskeleton of SKOV-3. Thus, mPt@PDA-RGD NPs presented great potential for targeted tumor photothermal ablation and migration inhibition.

The use of omics techniques to analyze the differences between genetic engineering organisms and their parents can identify unintended effects and explore whether such unintended effects will have negative consequences. In order to evaluate whether genetic engineering will cause changes in crops beyond the changes introduced by conventional plant breeding, we compared the extent of transcriptome and metabolome modification in the leaves of three lines developed by RNA interference (RNAi)-based genetic engineering and three lines developed by conventional breeding. The results showed that both types of plant breeding methods can manifest changes at the short interfering RNA (siRNA), transcriptomic, and metabolic levels. Relative expression analysis of potential off-target gene revealed that there was no broad gene decline in the three RNAi-based genetic engineering lines. We found that the number of DEGs and DAMs between RNAi-based genetic engineering lines and the parental line was less than that between conventional breeding lines. These unique DEGs and DAMs between RNAi-based genetic engineering lines and the parental lines were not enriched in detrimental metabolic pathways. The results suggest that RNAi-based genetic engineering do not cause unintended effects beyond those found in conventional breeding in maize.

This paper compares classic (continuous) fatigue tests and fatigue tests carried out with time intervals of no stress in rock salt using a multifunctional testing machine and acoustic emission equipment. The results show that time intervals of no stress have a strong impact on the fatigue activity of rock salt. In fatigue tests with intervals, the residual strain in circles following an interval (α circles) is generally larger than that in circles before the intervals (β circles). The insertion of a time interval with no stress in the fatigue process accelerates the accumulation of residual strain: the longer the interval, the faster the residual strain accumulates during the fatigue process and the shorter the fatigue life of the rock salt. α circles produce a greater number of acoustic emission counts than β circles, which demonstrates that residual stress leads to internal structural adjustment of rock salt on a mesoscopic scale. During intervals of no stress, acoustic emission activity becomes more active in α circles because of reverse softening caused by the Bauschinger effect, which accelerates the accumulation of plastic deformation. A qualitative relationship between the accumulated damage variable and the time interval is established. A threshold in the duration of the time interval exists (around 900 s).