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• Urban parks averagely cool down 2.34 ± 0.07 °C, 151.43 ± 4.39 m. • Urban parks' cooling effect accumulates to 108.55 °C • m. • Suburb residents have more difficulty accessing parks' cooling services. The rapid urbanization process has given rise to urban heating problem and social stratification, prompting calls to evaluate and improve the quality and equity of parks' cooling service. Our study quantified cooling effect of 1,337 parks from both maximum and accumulation perspectives and investigated cooling accessibility through network analysis in 26 cities of Yangtze River Economic Belt (YREB), China's largest sustainability experiment. 1,189 (88.93%) parks showed significant cooling effect. On average, per park cooled down 2.34 ± 0.07 °C and 40.34 ± 1.17 ha, which was more than four times park area. The accumulative cooling intensity and gradient averaged at 108.55 ± 3.15 °C • m and 0.64 ± 0.02 °C, respectively. Our study also uncovered inequity in cooling accessibility in hot summers, as about 40.3% residents could not access to parks' cooling service within 30-min walk. Suburban residents had more difficulty accessing to parks' cooling services. This study can guide greater planning and design of parks to move toward a more equitable and livable direction across different urbanization hierarchy cities. [ABSTRACT FROM AUTHOR]

This work evaluated biological effect of nC 60 on Scenedesmus obliquus . The cells were exposed to various concentrations of nC 60 for 7 days. Low-dose of nC 60 was found to have a minor growth inhibitory effect. The transcriptomics and metabolomics were integrated to examine intricate molecular and cellular effects of nC 60 on Scenedesmus obliquus . We found that Scenedesmus obliquus cells exposed to nC 60 had several significant alterations in cellular transcription and biochemical processes. During the 7-day exposure to nC 60 , 2234 and 2,448 unigenes were differentially expressed by 0.1 mg/L and 1 mg/L nC 60 -treated groups compared with the control, including 2085 or 2247 up-regulated genes and 149 or 201 down-regulated genes, respectively. We successfully identified 22 metabolites, including 6 significantly changed metabolites, such as sucrose, d -glucose, and malic acid. The citrate cycle (TCA cycle) (ko00020) was the main target of both differentially expressed genes and metabolic change. However, accumulation of sucrose (end-product) could have induced feedback inhibition of photosynthesis in Scenedesmus obliquus , explaining the slight growth inhibition observed. The results provided a mechanistic understanding of the growth inhibition of nC 60 toxicity. These genes and metabolites are useful biomarkers for future studies and offer new insights into the early detectable changes in Scenedesmus obliquus with nC 60 exposure. [ABSTRACT FROM AUTHOR]

Abstract: An approximate algorithm of exposure distribution on photoresist for the case of large exposure dose is obtained on the basis of the algorithm reported in [X. Dong, C. Du, S. Li, C. Wang, Y. Fu, Control approach for form accuracy of microlenses with continuous relief, Opt. Express 13 (2005) 1353–1360] via analyzing a PAC concentration distribution inside the photoresist. We analyzed the fabrication errors of the micro-optical structures which are caused by the approximate algorithm. The relief form error originating from the measurement errors of characteristics parameters of the photoresist is analyzed as well. A valid approach for a quick and accurate design of the exposure distribution is provided accordingly. As an example, a saw-tooth grating with 75μm relief depth was designed and fabricated so as to verify the new algorithm. Our measurement results show that root mean square (rms) value is less than 0.81μm. The quick algorithm can satisfy the requirements of micro-optical systems for practical applications. [Copyright &y& Elsevier]

Light guided head-up display is an advanced display technology that realizes miniaturization and lightweight. It is very suitable for the increasingly stringent requirements of assembly space for HUD equipment in avionics and vehicle cockpits. This paper describes the basic principle of avionics light guided head-up display technology its technological advancement and feasibility, proposes a new type of light guided head-up display system, and analyzes the essential elements of light guided display technology in engineering application of head-up display for the first time. In this study, a polarization splitter array was embedded in the planar waveguide combiner to improve the transmittance of exterior light and the efficiency of light bearing virtual image and suppress the " window-blinds effect" of light guided head-up display. Experiments show that the transmittance rate of Combiner is over 80%, the imaging efficiency is better than 10%, and the virtual image is clear, uniform and continuous. This study is helpful to promote the application of the light guided display technology in head-up display system. The light guided display technology is expected to be developed in the field of avionics and vehicle fields. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are one of the most widely used nanomaterials. Their fast-growing utilization has increased the occurrence of AgNPs in the environment, posing potential health and ecological risks. In this study, we conducted chronic toxicity tests and investigated the metabolic changes of the growing Daphna similis with exposure to 0, 0.02, and 1 ppb AgNPs, using non-targeted mass spectrometry-based metabolomics. To the best of our knowledge, this study is the first to report the baseline metabolite change of a common aquatic organism Daphnia crustacean through its life-cycle. The results show a dynamic kinetic pattern of the growing Daphnia 's metabolome underwent a cycle from day 0 to day 21, with the level of metabolites gradually increasing from day 0 to day 13, before falling back to the baseline level of day 0 on day 21. As for the samples exposed to environmental concentrations of AgNPs, although without morphological or structural changes, numerous metabolite changes occurred abruptly during the first 10 days, and these changes reached steady state by day 13. The significant changes in certain metabolites, such as amino acids (serine, threonine and tyrosine), sugars ( d -allose) and fatty acids (arachidonic acid) revealed new insights into how these metabolites in Daphnia respond to chronic AgNPs stress. These findings highlight the capability of metabolomics to discover early metabolic responses to environmental silver nanoparticles. [ABSTRACT FROM AUTHOR]

Urban parks are considered as an effective, sustainable, and affordable heat mitigation strategy. At present, there is a lack of understanding of the carbon saving potential of urban parks in the context of urban warming. Here we provide a simple approach to estimate the potential carbon savings due to heat mitigation based on analysis of 1510 parks in 26 major urban areas of the years 2017–2021 within the Yangtze River Economic Belt (YREB), China's largest sustainability experiment. On average, an urban park with 26.9 ± 1.5 ha in the YREB could avoid 23.7 ± 1.6 t CO 2 (1.08 ± 0.03 t CO 2 /ha) in emissions due to heat mitigation per summer day. Considered altogether, the 1510 urban parks can offset 5.37% of the daily fossil fuel emissions in the YREB. To boost carbon saving efficiency, lush vegetation should be first considered and the coupled green and blue infrastructures are always advocated. The total parks carbon saving of cities gradually improved along the Yangtze River from west to east, among which Shanghai city (in the east of the YREB) is with the largest amount (4341 t CO 2). The strategies using exquisite landscape design for improving carbon saving may differ across different climate zones. These findings can inform decision-making for urban sustainable development and climate change mitigation, which may benefit China's movement toward carbon neutrality. [ABSTRACT FROM AUTHOR]

Recently, it was experimentally shown that barium titanate (BaTiO 3 ) glass microsphere immersed in the liquid can be used for super-resolution imaging. However the inherent physical mechanism is still not clear. In this paper, spectrum analysis method is adopted to investigate the effect of liquid immersion to microsphere based optical super-resolution imaging. By tracking the propagation of part of the evanescent wave of the object's spectrum, the range of immersed-liquid's refractive index to achieve super resolution can be derived. To verify this analysis, we theoretically model the imaging process with finite-difference time-domain (FDTD) and angular spectrum propagation method. The result shows that only the BaTiO 3 microsphere immersed in the liquid with moderate refractive index, the super-resolution can be achieved. And the lower refractive index of liquid corresponds to larger magnification. [ABSTRACT FROM AUTHOR]

China has proposed the goals of a carbon peaking target in 2030 and a carbon neutrality target in 2060 to mitigate climate change. In China, Eco-industrial parks (EIPs) are one of the platforms for achieving energy conservation and emission reduction. This study aims to investigate the future CO 2 emissions reduction potential by evaluating two different types of national EIPs in China. Firstly, we constructed carbon emission inventories for EIP-N in Zhejiang Province and EIP-L in Shandong Province. Subsequently, leveraging these inventories, we developed an integrated model aimed at predicting the carbon emission peaks for both EIPs and discerning the main contributors. Secondly, we took EIP-N and EIP-L as examples and applied the Long-range Energy Alternatives Planning (LEAP) model to establish three different scenarios for analyzing the future trends in carbon emissions. In a Business as usual (BAU) scenario (continue the current energy conservation and emission reduction policies), EIP-L can achieve carbon peaking, while the carbon emissions of EIP-N will continue to increase. In the Emissions control (EMC) scenario (considering the reduction of fossil fuels and the increased use of cleaner energy sources), EIP-N and EIP-L are projected to peak in 2029 and 2027, respectively. In the Reinforce mitigation (RFM) scenario (with fewer emissions from fuels and a higher share of clean energy generation), both EIPs are expected to achieve carbon peaking by 2025. Finally, we proposed the deep decarbonization of EIPs with different industrial characteristics. This study applied the LEAP model to the EIP scale, explored the paths of deep decarbonization development in different EIPs under the constraint of dual-carbon targets, providing a demonstration for China and other developing countries to achieve the goal of carbon capping in EIPs during rapid industrialization. [ABSTRACT FROM AUTHOR]

• Protein folding or unfolding in solution bring about terahertz spectrum changes. • Terahertz spectrum can indicate protein denaturation induced by pH or temperature. • Terahertz spectroscopy is a potential label-free protein drugs' quality control tool. Polypeptides and protein drugs have received enormous attention from pharmaceutical industry, medical sector and consumer groups because of a favourable combination of their bioactivity, specificity and overall success rate for the treatment of a variety of diseases. The efficacy and safety of drugs may be degraded due to fluctuating environmental factors, accompanied by changes of the natural conformation of protein. Thus, it is necessary and meaningful to evaluate drug status before use. To that end, the evolving new and pre-existing protein activity/conformation technologies have proven to ensure the safety of drug use consistently. Recently, terahertz time-domain spectroscopy (THz-TDS) has demonstrated suitability for label-free and non-destructive detection of polypeptide and protein conformational changes. In this paper, THz optical parameters of pepsin solutions under different temperatures and with varying pH are measured to demonstrate the feasibility and the considerable potential of THz spectroscopic method in detecting protein drugs. In cases where temperature or pH change is apparent, the THz absorption coefficient, the refractive index, and the dielectric loss tangent change noticeably, independently verified by enzyme activity testing. These findings strongly support the conclusion that THz spectroscopy of pepsin solutions can be used for qualitative analysis to identify the folding or unfolding of protein drugs caused by changes of environmental factors, laying the foundation of a new label-free method for quality control of protein drugs. [ABSTRACT FROM AUTHOR]

Tunable-sensitivity and flexibility are considered as two crucial characteristics for future pressure sensors or electronic skins. By the theoretical calculation model, we simulated the relationship curve between the sensitivity and PDMS pyramids with different spacings, and found that the spacing of pyramids is a main factor to affect the sensitivity of the capacitance pressure sensor. Furthermore, we fabricated the capacitance pressure sensors using graphene electrodes and the PDMS pyramid dielectric layers with different spacings. The measurement data were consistent with the simulation results that the sensitivity increases with the spacing of pyramids. In addition, graphene electrode exhibits prefect flexibility and reliability, while the ITO electrode would be destroyed rapidly after bending. These graphene pressure sensors exhibit the potential in the application in the wearable products for monitoring breath, pulse, and other physiological signals. [ABSTRACT FROM AUTHOR]

The wide applications cause a large amount of rare earth elements (REEs) to be released into the environment, and ultimately into the human body through food chain. Toxic effects of REEs on humans have been extensively studied, but their toxic effects and binding targets in cells are not understood. Delayed outward potassium channels (K + channels) are good targets for exogenous substances or clinical drugs. To evaluate cellular toxicities of REEs and clarify toxic mechanisms, the toxicities of REEs on the K + channel and their structural basis were investigated. The results showed that delayed outward potassium channels on the plasma membrane are the targets of REEs acting on living organisms, and the changes in the thermodynamic and kinetic characteristics of the K + channel are the reasons of diseases induced by REEs. Two types of REEs, a light REE La 3+ and a heavy REE Tb 3+ , displayed different intensity of toxicities on the K + channel, in which the toxicity of Tb 3+ was stronger than that of La 3+ . More interestingly, in comparison with that of heavy metal Cd 2+ , the cytotoxicities of the light and heavy REEs showed discriminative differences, and the cytotoxicity of Tb 3+ was higher than that of Cd 2+ , while the cytotoxicity of La 3+ was lower than that of Cd 2+ . These different cytotoxicities of La 3+ , Tb 3+ and Cd 2+ on human resulted from the varying binding abilities of the metals to this channel protein. [ABSTRACT FROM AUTHOR]

THz reflective time domain spectroscopy (THz-RTDS) has been considered as an effective method to detect hidden objects with potential for supplementing other NDE technologies for foam composite adhesive structure debonding defects. PMI (Polymethacrylimide) is a heat-resistant foam material, with the highest strength and stiffness to weight ratio. It is widely used in various parts of airplanes, especially the wing leading edge and rudder, landing gear doors, wing-body/wingtip fairings and so on. We analyzed the features of adhesive debonding defect based mainly on the variation of the time-domain wave form and compared with the inclusion defect. The quantification of degrees of adhesive debonding can be readily achieved with THz-RTDS images based on the delay of the wave front and the main reflection time-domain waveforms. Typical accuracy of about 100 μm was achieved. [ABSTRACT FROM AUTHOR]

Surface plasmon (SP) holography produced by evanescent electromagnetic waves as a reconstruction light has been shown to be capable of effectively eliminating the zero order diffraction. In this paper, an interference model and algorithm based on point source and surface plasmon wave (SPW) are proposed, which is important to get the relief profile distribution of SP hologram theoretically. Numerical simulation of the reconstruction process is performed through finite element method (FEM) and the result verifies the feasibility of the proposed algorithm. The method could be viable for the development of SP holographic dynamic display technology. [ABSTRACT FROM AUTHOR]

This manuscript presents a design method and corresponding image processing algorithms of a spherical artificial compound eye. The artificial compound eye is composed of multi-dimensional sub-eye imaging channels pointing to different directions. By using the principle of geometrical optics and imaging optics, the design method of the multi-dimensional imaging structure was analyzed. To satisfy the practical requirement of the structure, the image processing algorithm based on the segmentation rotation projection technology was studied. In order to validate the above design method and image processing algorithm, a spherical compound eye consisting of 37 imaging channels was fabricated and the corresponding imaging experiments were carried out. The results show that the field of view (FOV) of the imaging structure is up to 118° and the structure meets the practical requirements. [ABSTRACT FROM AUTHOR]

The original design method for diffractive optical elements (DOEs) is limited to cases of small-angle diffraction due to the Fresnel or Fraunhofer diffraction integral. In this paper, we propose a new method based on the Rayleigh–Sommerfeld diffraction integral, which does not have this limit. In this method, the target intensity distribution is first modified via coordinate transformation and intensity adjustment. Then, the modified Gerchberg–Saxton algorithm is used to achieve the phase distribution of the DOE. To verify this method, simulations and experiments are performed. The results show that the original method is effective only when the full diffraction angle of the DOE is below 25°. Conversely, this method can achieve the target with both small and large diffraction angles. [ABSTRACT FROM AUTHOR]

A novel strategy which combines iteratively cubic spline fitting baseline correction method with discriminant partial least squares qualitative analysis is employed to analyze the surface enhanced Raman scattering (SERS) spectroscopy of banned food additives, such as Sudan I dye and Rhodamine B in food, Malachite green residues in aquaculture fish. Multivariate qualitative analysis methods, using the combination of spectra preprocessing iteratively cubic spline fitting (ICSF) baseline correction with principal component analysis (PCA) and discriminant partial least squares (DPLS) classification respectively, are applied to investigate the effectiveness of SERS spectroscopy for predicting the class assignments of unknown banned food additives. PCA cannot be used to predict the class assignments of unknown samples. However, the DPLS classification can discriminate the class assignment of unknown banned additives using the information of differences in relative intensities. The results demonstrate that SERS spectroscopy combined with ICSF baseline correction method and exploratory analysis methodology DPLS classification can be potentially used for distinguishing the banned food additives in field of food safety. [ABSTRACT FROM AUTHOR]

With the rapid process of urbanization and global warming, extreme heat events occur frequently, endangering urban dwellers' health. Urban parks could alleviate the severe urban heating climate. However, due to the scarcity of urban land, it is impractical to plan and design urban parks by increasing the blue-green space without restriction. Few studies have focused on optimization and the equity of the parks' cooling service. This study quantifies four cooling indicators of urban parks in Wuhan city, park's cooling intensity (PCI), park's cooling area (PCA), park's cooling gradient (PCG), and park's cooling efficiency (PCE), analyze the drivers for four indicators, discuss different cooling bundles (urban parks with similar specific cooling ability are grouped into bundles) for the specific heat mitigation demands, and map the spatial accessibility for residents to parks' PCA using spatial network analysis. We find that 54 of 60 urban parks have significant cooling effect, with average PCI of 3.5 ± 0.2 °C, PCA of 131.6 ± 29.6 ha, PCG of 17.9 ± 1.5 °C/km, PCE of 4.5 ± 0.8. Blue and green infrastructure inside parks and impervious surface ratio surrounding the parks play significant roles in cooling service. Larger urban parks usually have larger PCA, but lower PCG and PCE. Five cooling bundles clustered with specific dominant cooling indicators could be references for the specific demand considering tradeoffs in urban parks' design and planning. Taking one step further, we unmask the unequal accessibility of the urban parks cooling service in one extreme heat day: 83.6% of the residents in the central area can enjoy the urban parks' cooling service within 30-min walk, while most residents (74.4%) in suburbs are not able to access to the cooling service within 30-min walk. Our study should be valuable for the urban planning and practice to find heat mitigation solutions and improve residents' heat comfort, also helpful for local municipalities to consider the urban parks' service provision for marginal groups. • The cooling effect of parks within Wuhan was 3.5 ± 0.2 °C in an extreme heat event. • Blue and green infrastructure inside parks play vital roles in cooling service. • Small comprehensive parks have efficient cooling effect with high land scarcity. • Urban parks' service provision should be considered for marginal groups. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the effects of exposed sensing region length on fiber optic sensor based on surface plasmon resonance (SPR) had been experimentally investigated. The refractive index sensitivity of SPR fiber optic sensor increased with increasing refractive index. Compared to other two counterparts, the sensor with short sensing region length of 5mm demonstrated the highest refractive index sensitivity. For the change in the same magnitude of refractive index, this sensor of 5mm sensing region length showed significantly different dynamic response curve when it was exposed to ionic (NaCl solution) and non-ionic (ethanol) solution. This result suggests that ions have dramatic influence on the resonance wavelength of surface plasmon resonance spectrum, due to the interaction of ions with gold film surface. This feature provides a great potential of SPR fiber optic sensor to on-line monitor of flowing solution. [Copyright &y& Elsevier]