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Macroinvertebrate assemblages are structured by a number of abiotic and biotic factors interacting simultaneously. We investigated macroinvertebrate assemblages along gradients of human disturbance and morphometric characteristics in five lakes connected by the same stream. We aimed to assess the relative effects of environmental gradients on macroinvertebrate assemblages and to investigate whether water quality effects on the assemblages were correlated with buffer land use. There were significant differences in macroinvertebrate community compositions among lakes, and our results indicated that oligochaetes (mainly Limnodrilus) and insects (mainly Chironomus) contributed highly to the differences. We used redundancy analysis with variation partitioning to quantify the independent and combined anthropogenic effects of water quality and land use gradients on the macroinvertebrate community. The independent effect of water quality was responsible for 17% of the total variance in macroinvertebrate community composition, the independent effect of buffer land use accounted for 6% of variation, and the combined variation between land use change and water quality accounted for 12%. Our study indicated that both the independent effects of land use and within‐lake water quality can explain the influence in macroinvertebrate assemblages, with significant interactions between the two. This is rather important to notice that changes in buffer land use generally may alter nutrient inputs and thus severely affect abiotic conditions encountered by macroinvertebrate. Our study demonstrates that considering buffer zone effects explicitly may be significant in the selection and application of conservation and management strategies., Our study indicated that both the independent effects of land use and within‐lake water quality can explain the influence in macroinvertebrate assemblages, with significant interactions between the two. This is rather important to notice that changes in buffer land use generally may alter nutrient inputs and thus severely affect abiotic conditions encountered by macroinvertebrate.

The construction of green finance index is a three-tiered process that involves macroeconomic, ecological, and monetary indicators. Therefore, this research is one of the first thorough assessments of the impacts of green financing regulations in China, examining 30 provinces during the period of 2010 to 2017. Data envelopment analysis models for 30 provinces in China have been tested by using non-radial models and longitudinal datasets. The findings demonstrate that between 2010 and 2017, the efficiency of China's provinces such as Beijing, Fujian, Guangdong, Hainan, Hebei, Jiangsu, Liaoning, Shandong, Shanghai, Tianjin, and Zhejiang and provinces of central regions as well as western provinces of country green economies has increased with distinct geographical disparities becoming more apparent. The geographical distribution of economic efficacy in the green economy is greatest in the eastern parts and poorest in the Chongqing, Gansu, Guangxi, Guizhou, Inner Mongolia, Ningxia, Qinghai, Shaanxi, Sichuan, Tibet, Xinjiang, and Yunnan. The study revealed that sustainable financial growth may be accomplished via the creation of green financing, which can be achieved by employing different solutions across the macroeconomic, institutional, and ecological considerations. The western and central areas, however, have a significant negative association. There are substantial variations in factors at the state and federal level from the viewpoint of dependent variables. Eventually, the research offers some suggestions for future ecological impact of China, along with the creation of new environmental legislation.

Intel SGX Guard eXtensions (SGX), a hardware-supported trusted execution environment (TEE), is designed to protect security-sensitive applications. However, since enclave applications are developed with memory unsafe languages such as C/C++, traditional memory corruption is not eliminated in SGX. Rust-SGX is the first toolkit providing enclave developers with a memory-language. However, Rust is considered a Systems language and has become the right choice for concurrent applications and web browsers. Many application domains such as Big Data, Machine Learning, Robotics, Computer Vision are more commonly developed in the python programming language. Therefore, Python application developers cannot benefit from secure enclaves like Intel SGX and rust-SGX. To fill this gap, we propose Python-SGX, which is a memory-safe SGX SDK providing enclave developers a memory-safe Python development environment. The key idea is to enable memory-safe Python language in SGX by solving the following key challenges: (1) defining a memory-safe Python interpreter (2)replacing unsafe elements of Python interpreter with safe ones,(3) achieving comparable performance to non-enclave Python applications, and (4) not introducing any unsafe new code or libraries into SGX. We propose to build Python-SGX with PyPy, a Python interpreter written by RPython, which is a subset of Python, and tame unsafe parts in PyPy by formal verification, security hardening, and memory safe language. We have implemented python-SGX and tested it with a series of benchmarks programs. Our evaluation results show that Python-SGX does not cause significant overhead.

In spring, summer, autumn 2015, we studied the seasonal variation of phytoplankton community structure in six rivers within Duobukuer Nature Reserve, and made preliminary evaluation of the water quality in Duobukuer Nature Reserve based on phytoplankton diversity. The results showed that a total of 7 phyla, 41 genera, 66 species and varieties of phytoplankton were identified in Duobukuer Nature Reserve; the annual species composition was dominated by diatom (59%) which also preponderated in dominant species (84.3%), biomass (68%) and abundance (75%), with no significant seasonal variation. Shannon-Wiener diversity index (H') and Pielou evenness index (J) were used to evaluate the water quality in 13 sampling points, and the results showed that the water quality was good in Duobukuer Nature Reserve, the sampling points 5, 6 and 12 presented β-pollution, and other sampling points were in an oligosaprobic-clean state.

Summary Alkalinity stress is common in cultured aquatic animals and considered to be one of the major stress factors for fishes when they are transferred to saline-alkali waters. To evaluate potential effects of alkalinity on the developmental biology of Oryzias latipes, fertilized eggs, larvae and breeding fish were exposed to different carbonate alkalinity concentrations of 1.5–64.5 meq l−1, for 9, 120, and 60 days, respectively. The mortality of embryos significantly increased when exposed to the high concentrations (16.5–64.5 meq l−1). Although more than 50% of survived embryos hatched in 16.5 and 31.4 meq l−1 concentrations of carbonate alkalinity, most were not able to swim up after hatching. Morphological abnormalities such as coagulated embryos, halted embryo development, and hatching failure were observed at stages 15, 29–33 and 38 in high concentrations (31.4, 64.5 meq l−1). Almost all larvae in 16.5 and 31.4 meq l−1 treatments died 70 d post-hatch. Growth of juveniles exposed to carbonate alkalinity of 5.3 and 8.8 meq l−1 was not significantly different at 70 d and 120 d post-hatch. The number of eggs released by breeders, the fertilization rate and the hatching rate of eggs were significantly lower in the 31.4 meq l−1 treatment than in other treatments. Although medaka are capable of surviving in high alkalinities (31.4, 64.5 meq l−1) for an extended period of time, these conditions are stressful to the fish, especially at the embryonic and reproductive stages.

The design of a novel elliptically cylindrical transparent concentrator with functions of both electromagnetic transparency and electromagnetic concentration is put forward based on the form invariance of Maxwell’s equations in different coordinate transformation and transformation optics theory, and through the design of material constitutive parameters (permittivity and permeability) to guide the electromagnetic wave propagation. The electromagnetic wave transparent body does not prevent the transmission of electromagnetic waves that can interact in the cloak. An electromagnetic wave concentrator is an electromagnetic device that controls the electromagnetic waves to focus on an area or at a point to realize the electromagnetic wave energy concentration according to the requirement when the electromagnetic waves are incident on the device. In this paper, the expressions of the relative permittivity and permeability tensors in every layer of the electromagnetic device are derived by compression transformation and extension transformation. Then full-wave simulations for the electromagnetic device are performed by using finite-element software. The distributions of z-component of the magnetic field for the electromagnetic waves incident from different directions are obtained. Simulation results confirm the validity of the design method and the constitutive parameter tensors. Finally, effect of electromagnetic loss on the performance of the device is also discussed. To a certain extent, the function of the device will be weakened when the electromagnetic loss increases gradually. The design method proposed in this paper provides a new approach that can be used to design other novel electromagnetic devices.

Transmission spectra of coupled cavity structures (CCSs) in two-dimensional (2D) photonic crystals (PCs) are investigated using a coupled mode theory, and an optical filter based on CCS is proposed. The performance of the filter is investigated using finite-difference time-domain (FDTD) method, and the results show that within a very short coupling distance of about 3λ, where λ is the wavelength of signal in vacuum, the incident signals with different frequencies are separated into different channels with a contrast ratio of 20 dB. The advantages of this kind of filter are small size and easily tunable operation frequencies.