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In vitro or in vivo fluorescence imaging based on quantum dots (QDs) has shown promise for the noninvasive diagnosis of atherosclerosis. However, simultaneous in vitro and in vivo imaging remains challenging due to the limitation of the current synthesis method of dual-emission QDs (dual-emitting hybrid QDs, and broad-spectrum emitting QDs). Herein, we fabricate a dual-emission (visible region and near-infrared region emission) QDs (ZAISe/ZnS) via the "bottom to up" method of a quaternary inorganic compound for the foam cells and atherosclerosis plaque imaging simultaneously without the intricate size modulation and the strict optical filter requirements. The oil-soluble ZAISe/ZnS is further encapsulated with bovine serum albumin (BSA) to realize phase transfer and ultimately possess the inflammation-targeting properties via biomimetic treatment with MMV (macrophage-derived micro-vesicle). The results first indicate that the as-constructed ZAISe/ZnS@BSA@MMV could accurately locate the foam cells and conduct long-term imaging of the atherosclerotic plaque, which provides a new strategy for the early and noninvasive diagnosis of atherosclerosis.

Porous carbon nanostructures are promising supports for stabilizing the highly dispersed metal nanoparticles and facilitating the mass transfer during the reaction, which are critical to achieve the high efficiency of hydrogen generation from sodium borohydride dehydrogenation. Herein, the catalytically active porous architectures are simply prepared by using 2-methylimidazole and melamine as reactive sources. The structural and compositional characterizations reveal the coexistence of metallic cobalt and N-doped carbon in porous architectures. Electron microscopy observations indicate that the synthesized products are smartly constructed from the carbon nanosheets with densely dispersed Co nanoparticles. Due to the notable structural features, the prepared Co@NC-600 sample presents the highly efficient activity for catalytic hydrolysis of NaBH4 with a hydrogen generation rate of 2574 mL min−1 gcat−1 and an activation energy of 47.6 kJ mol−1. The catalytically active metallic Co and suitable support-effect of N-doped carbon are responsible for catalytic dehydrogenation.

Background Sudden sensorineural hearing loss (SSNHL) is a common disease in otology, and steroids play an important role in its treatment. Steroids can be administered systemically or locally, and the efficacies of different administration routes remain controversial. Methods We searched the Cochrane, EMBASE, PubMed, Web of Science, CNKI, Wanfang and Weipu databases for randomized controlled trials (RCTs) on glucocorticoid treatments for SSNHL to compare the efficacy of topical and systemic steroid administration. The Review Manager 5.4 software was used for synthesis of data: the rate of reported hearing improvement and change in pure-tone audiometry (PTA). Results In all the included studies, when intratympanic administration was compared to systemic therapies, the risk difference (RD) using reported hearing improvement as an outcome measure was 0.08 (95% CI: 0.01–0.14, I2 = 45%). Using PTA changes as an outcome measure in 4 studies, the mean difference (MD) was 10.43 dB (95% CI: 3.68–17.18, I2 = 81%). Hearing improvement RD was also compared among different types of steroid, recovery criteria, follow-up times and diagnostic criteria, and showed no significant differences exception for recovery criteria (>10 dB) (RD -0.06, 95% CI: 0.14-0.2, I2 = 0%). Conclusion As the initial treatment for SSNHL, topical steroids seem to be superior to systemic steroid administration, especially in patients with contraindications to systemic steroids usage. However, further verification based on high-quality research is needed.

The blood-brain barrier (BBB) is the major obstacle limiting the reach of therapeutic drugs into the brain. Herein, an aspirin-based anti-inflammatory replenisher (aspCD) was fabricated by carbonizing aspirin to deliver drugs into the brain visually. The as-prepared aspCD combined the BBB-penetrating and anti-inflammatory effects of aspirin with the fluorescent and drug-loading properties of carbon dots (CDs), thereby delivering therapeutic drugs into the brain and acting as imaging agent as well as anti-inflammatory replenisher. In vivo experiments of mice and zebrafish revealed that fluorescence aspCD could effectively penetrate BBB. In vitro and in vivo inflammatory models demonstrated that aspCD could be regarded as an excellent anti-inflammatory replenisher. In addition, as a functional carrier, aspCD was proved to be capable of loading drugs with different polarity. In summary, carbonization of active precursors (therapeutic drugs) into CDs could be a promising strategy to achieve the loading and visualization of drugs as well as the retainment of their biological activities.

Introduction Influenza has been linked to the crowding in emergency departments (ED) across the world. The impact of the Coronavirus Disease 2019 (COVID-19) pandemic on China EDs has been quite different from those during past influenza outbreaks. Our objective was to determine if COVID-19 changed ED visit disease severity during the pandemic. Methods This was a retrospective cross sectional study conducted in Nanjing, China. We captured ED visit data from 28 hospitals. We then compared visit numbers from October 2019 to February 2020 for a month-to-month analysis and every February from 2017 to 2020 for a year-to-year analysis. Inter-group chi-square test and time series trend tests were performed to compare visit numbers. The primary outcome was the proportion of severe disease visits in the EDs. Results Through February 29 th 2020, there were 93 laboratory-confirmed COVID-19 patients in Nanjing, of which 40 cases (43.01%) were first seen in the ED. The total number of ED visits in Nanjing in February 2020, were dramatically decreased (n = 99,949) in compared to January 2020 (n = 313,125) and February 2019 (n = 262,503). Except for poisoning, the severe diseases in EDs all decreased in absolute number, but increased in proportion both in year-to-year and month-to-month analyses. This increase in proportional ED disease severity was greater in higher-level referral hospitals when compared year by year. Conclusion The COVID-19 outbreak has been associated with decreases in ED visits in Nanjing, China, but increases in the proportion of severe ED visits.

All-inorganic perovskite nanocrystals have held great promise as incredibly effective luminescent materials and also have been synthesized efficiently by room temperature approaches. Toluene, a high toxicity solvent, is often used as a valid antisolvent in ligand-assisted reprecipitation strategy, which badly restricts the commercial application of this convenient method. Here, aiming to address the toluene toxicity issue, the low toxic tetraethyl orthosilicate (TEOS) is employed as a new alternative antisolvent to achieve high uniform and composition dependent luminescent all-inorganic perovskite Cs4PbX6 (X = I, Br, Cl) combined with CsPbX3 (X = I, Br, Cl) nanocrystals with tunable emission large-span wavelengths (626–437 nm) and remarkably narrow full width at half-maximum (FWHM) monochromaticity (down to 19 nm). Meanwhile, the ratio of CsBr to PbBr2 is proved to be a critical factor to control the crystalline phase of the resulting perovskite nanocrystals. Additionally, one monochromatic light-emitting diode (LED) lamp with brightly pure green emission is fabricated based on bromine-based perovskite nanocrystals. This newly developed low toxicity antisolvent synthesis (LTaS) is suitable candidate for commercial production in an environmentally-friendly way, and the as-obtained perovskite materials with superior optical merits will be brought to the forefront of lighting and displays.

A major challenge in applying Model Predictive Control (MPC) to building automation and control (BAC) is the development of a simplified mathematical model of the building for real-time control with fast response times. However, building models are highly complex due to nonlinearities in heat and mass transfer processes of the building itself and the accompanying air-conditioning and mechanical ventilation systems. This paper proposes a method to develop an integrated state-space model (SSM) for indoor air temperature, radiant temperature, humidity and Predicted Mean Vote (PMV) index suitable for fast real-time multiple objectives optimization. Using the model, a multi-objective MPC controller is developed and its performance is evaluated through a case study on the BCA SkyLab test bed facility in Singapore. The runtime of the MPC controller is less than 0.1 s per optimization, which is suitable for real-time BAC applications. Compared to the conventional ON/OFF control, the MPC controller can achieve up to 19.4% energy savings while keeping the PMV index within the acceptable comfort range. When the MPC controller is adjusted to be thermal-comfort-dominant that achieves a neutral PMV index at most office hours, the system can still bring about 6% in energy savings as compared to the conventional ON/OFF control. NRF (Natl Research Foundation, S’pore) Accepted version

Quantitative analysis of Ni2+/Ni3+ using X-ray photoelectron spectroscopy (XPS) is important for evaluating the crystal structure and electrochemical performance of Lithium-nickel–cobalt-manganese oxide (Li[NixMnyCoz]O2, NMC). However, quantitative analysis based on Gaussian/Lorentzian (G/L) peak fitting suffers from the challenges of reproducibility and effectiveness. In this study, the Ni2+ and Ni3+ standard samples and a series of NMC samples with different Ni doping levels were synthesized. The Ni2+/Ni3+ ratios in NMC were quantitatively analyzed by non-linear least-squares fitting (NLLSF). Two Ni 2p overall spectra of synthesized Li [Ni0.33Mn0.33Co0.33]O2(NMC111) and bulk LiNiO2 were used as the Ni2+ and Ni3+ reference standards. Compared to G/L peak fitting, the fitting parameters required no adjustment, meaning that the spectral fitting process was free from operator dependence and the reproducibility was improved. Comparison of residual standard deviation (STD) showed that the fitting quality of NLLSF was superior to that of G/L peaks fitting. Overall, these findings confirmed the reproducibility and effectiveness of the NLLSF method in XPS quantitative analysis of Ni2+/Ni3+ ratio in Li[NixMnyCoz]O2 cathode materials.

Diabetes mellitus is one of the most common chronic diseases, and blood glucose monitoring benefits for diagnosis and management of diabetic mellitus. In this paper, a multimodal photoluminescence (PL) bio-platform, R-CDs/B2O3, with solid-state fluorescence, was developed by dispersing Rhodamine B carbon dots (R-CDs) in the matrix of boric acid (BA) as a simple, cheap agent for the visual assay of intracellular and serum glucose concentration, which was based on BA can specially bound with 1, 2-diol of glucose. The good linear relationship between the PL spectra of the R-CDs/B2O3 and glucose concentration indicated that R-CDs/B2O3 could dynamically monitor glucose concentration in vitro. Furthermore, the fluorescent color variations of R-CDs/B2O3 gel were monitored by the UV lamp and the green channel intensities of the colored images were processed by using the RGB option of a smartphone, manifesting that R-CDs/B2O3 could be used as a portable test gel for serum glucose. Significantly, it is convenient for self-monitoring of blood glucose for diabetic patients. The method was also successfully used for the assay of glucose in blood serum. Hence, the proposed fluorescence sensor opens the door for further research and development of more reliable non-enzymatic assays for continuous glucose monitoring systems.

In this work, we report a simple one-step hydrothermal synthesis strategy for depositing edge-rich MoS2 nanosheets on conductive layered Ti3C2 MXene, and demonstrate the formed MoS2/Ti3C2 heterostructure has significant active site exposure and effective charge carrier flow. The resulting MoS2/Ti3C2 exhibits enhanced activity and excellent stability for the catalytic reduction of 4-nitrophenol (4-NP). The optimal MoS2/Ti3C2 catalyst displays a high pseudo-first-order rate constant of 0.61 min−1, a conversion efficiency of 96.2% within 5 min and almost unchanged activity after six consecutive reaction cycles, which is better than the pristine MoS2 nanosheets. Moreover, the MoS2/Ti3C2 catalyst achieves a pseudo-first-order rate constant as high as 0.779 min−1 for the catalytic reduction of methylene blue (MB). This study opens up new opportunities for the design and development of cost-effective, efficient and reusable alternatives to noble metal catalysts based on molybdenum disulfide for environmental applications.

Increasing building constructions have become one of the fastest-growing drivers of carbon emissions. Energy conservation and carbon reduction in buildings have become increasingly crucial in the context of global carbon neutrality. This paper assesses the annual total energy and carbon embodied in the ten most intensively used building materials in China, aiming to find potential CO2 reduction opportunities in the construction industry from a macroscopic perspective. The results show that: (1) the embodied energy and carbon of cement, steel, and brick account for more than 70% of the total embodied energy and carbon of all building materials; (2) differences in the embodied energy and carbon between steel-concrete buildings and brick-concrete buildings are not distinct; (3) disparities in the embodied energy and carbon of building materials between different regions are significant. The eastern and south-eastern regions consume excessive building materials and embody significantly higher energy and carbon than other regions. Several strategies are provided for China's building sector in energy and carbon reduction.

The fluid velocity sensitivity (FVS) effect in coal reservoirs affects the production of coalbed methane (CBM) wells by generation of coal fines. In this work, coal samples from Baode Block, northeastern Ordos Basin were made into coal cores for FVS analysis under different initial permeabilities, injection volumes and injection intensities. Standard brine with a mineralization degree of 8% (the mass ratio of NaCl: CaCl 2 : MgCl 2 ·6H 2 O=7.0:0.6:0.4) was chosen as the driving fluid. Also, the production responses of CBM wells to FVS at different stages of drainage were discussed. The results show that there is a critical flow velocity for the generation of coal fines. Below this critical flow velocity, coal fines can discharge with fluid, which increases the reservoir permeability. Over this critical flow velocity, FVS tends to occur in coal reservoirs, which blocks the effective seepage paths and reduces reservoir permeability. Additionally, the larger the flow velocity and injection volume are, the greater the permeability damage rate is. But the increasing rate of permeability damage slows down, revealing that the damage of FVS to permeability mainly occurs in the initial period of coal fines migration. Moreover, abrupt increase of flow velocity can damage reservoirs and give rise to massive coal fines generation. During the drainage process of CBM wells, the FVS effect is mainly affected by the dropping rate of working fluid level at the stage of single-phase water. There exists a period of massive coal fines generation when the working fluid level first drops near the coal seam. In the stage of two-phase gas and water, the deposition rate of coal fines is faster and the migration distance is shorter than that in the stage of single-phase water. Due to the difficulty of coal fines discharge, the FVS effect tends to occur in this stage. In the stage of single-phase gas, the gas flow can make coal fines agitate partially. But the FVS effect is relatively weak as coal matrix shrinkage can improve the reservoir permeability to a large degree.

The human hands are among the earliest art themes, though reasons behind hand art in ancient times are not totally understood. In this study, we report handprints on bricks excavated from the Xiheidai cemetery, located in Jungar Banner, Inner Mongolia, China. Handprints were found on six bricks that came from the fillings of the tomb Ⅱ-M5. The burial style and funeral goods indicated that II-M5 belonged to the Jin-Yuan Period (金-元时期) (1115–1368CE). Data based on the morphology and measurements of handprints (especially that of the digits, sex, age, and height of people who left them) were analyzed in addition to hand preference. Results demonstrated that adult males left these handprints. The males had mainly middle posture and all were right-handed. The identities of the people who left these handprints are unknown. They might include brick-making laborers who had leisurely moments of artistic experimentation and experiences. However, these bricks were treated as waste. These discoveries bring out not only first-hand hand morphology beyond bones, but also vivid working scenarios of ancient laborers, adding to our understanding of working-class daily life in northern China nearly a millennium ago.

The adoption of model predictive control (MPC) for building automation and control applications is challenged by the high hardware and software requirements to solve its optimization problem. This study proposes an approximate MPC that mimics the dynamic behaviours of MPC using the recurrent neural network with a structure of nonlinear autoregressive network with exogenous inputs. The approximate MPC is developed by learning from the measured operation data of buildings controlled by MPC, therefore it can produce MPC-like control for buildings without needing to solve the optimization problem, significantly reducing the computation load as compared to MPC. The proposed approximate MPC is implemented in two testbeds, an office and a lecture theatre, to control the air-conditioning systems. The control performance of the approximate MPC is compared to MPC as well as the original reactive control of the two testbeds. The approximate MPC retained most of the energy and thermal comfort performance of MPC in both testbeds. For the office, the MPC and approximate MPC reduced 58.5% and 51.6% of cooling energy consumption, respectively, as compared to the original control. For the lecture theatre, the MPC and approximate MPC reduced 36.7% and 36.2% of cooling energy consumption, respectively, as compared to the original control. Meanwhile, both approximate MPC and MPC significantly improved indoor thermal comfort in the two testbeds as compared to their original control. Despite having minor degradation in control performance the approximate MPC was more than 100 times faster than MPC in generating optimal control commands in each time step. National Research Foundation (NRF) This research is financially supported by JTC Corporation (contract nos. N190107T00 and 2019-0607) and Smart Nation & Digital Government Office (SNDGO) of Singapore (Grant no. NRF2016IDM-TRANS001-031).

This study uses personal predispositions, attitudes towards food industry actors, media use and food consciousness as variables to explore trust in farm-raised and the degree to which respondents believe that aquaculture benefits their home state. The authors use a random sample mail survey of primary food shoppers in Wisconsin, a state in the Great Lakes region of the United States, where aquaculture is considered an emerging industry and fish sold for food are generally raised in manmade ponds or flow-through raceways. They find that trust in government agencies, grocery stores, food manufacturers/processors, perceived industry environmentalism and attention environmental news, were positively related to both trust in fish farmers and perceptions that benefits from fish farming accrue within the state. Although attention to environmental news and conservative ideology were positively related to trust in fish farmers, and a preference for GMO-free/organic foods was negatively related to the same, none of these three variables had a relationship to the perception that fish farming benefits the respondents' state. Implications are discussed.

Aiming at the problems of complicated data processing, large amount of calculation, perplexing results of the orthogonal test, and the uncertain multi-index decision-making matter that the decision-making index value is difficult to be refined, this paper studies the mixed multi-index gray target decision-making model with three data types of real value, interval number and triangular fuzzy number. According to the basic connotation of decision gray target and uncertain decision information, a hybrid ellipsoid gray target is defined, and a mixed gray target decision model is established. Then through the mechanical, durability, workability and other performance, the lightweight aggregate shotcrete (LWAS) was selected for the optimization of the mix ratio, and then compared with the traditional orthogonal results, and applied in the tunnel engineering. Therefore, the feasibility of applying LWAS in tunnel bolting and shotcreting supporting was explored to provide a theoretical reference for the application of LWAS in tunnel lining. The results show that: (1). The unit water consumption has some influences on the compressive strength, Splitting tensile strength, bonding strength and resistance to chloride ion permeability of the LWAS, and the optimal range of water consumption is 180–200 kg/m3. (2). The water-binder ratio has a significant effect on the compressive strength, splitting tensile strength and electric flux of LWAS, and has a small effect on the bonding strength. (3). The compressive strength, splitting tensile strength and electric flux of concrete increase with the decrease of water-binder ratio. (4). When the fly ash content is 0%, the 28 d compressive strength, splitting tensile strength and bonding strength of LWAS are the largest, and the electric flux is the smallest. (5). When the water-cement ratio is 0.42 with pure cement, the combination of gray targets has the best comprehensive decision-making performance, and it is recommended as the tunnel lining concrete ratio.

This article links the redevelopment of urban villages in China to the discourse on incremental housing schemes. Urban villages, due to the less regulated and more informal aspect of China's rapid urbanisation, house a large share of the migrant population. Current urban village redevelopment debates focus on state-initiated redevelopment, which involves large-scale demolitions and has become the norm in Beijing. The aim of this article is to make visible an alternative, village-initiated approach to redevelopment that is managed by the local village committee and that allows for incrementality and flexibility in a long-term transformation. This research traces the redevelopment process and subsequent transformation of Maquanying village over a period of more than 20 years. It focuses on the related decision-making and negotiation processes, and on socio-spatial changes during this time. In the context of the debate on incremental housing, the Maquanying approach can be understood as a locally initiated sites-and-services scheme within the Chinese environment. Both indigenous villagers and migrants are included and compared with other urban villages, higher standards of housing are delivered. The article argues that the redevelopment principles and strategies embedded in this approach can be transferred to other urban villages in China.

A model predictive control system with adaptive machine-learning-based building models for building automation and control applications is proposed. The system features an adaptive machine-learning-based building dynamics modelling scheme that updates the building model regularly using online building operation data through a dynamic artificial neural network with a nonlinear autoregressive exogenous structure. The system also employs a multi-objective function that could optimize both energy efficiency and indoor thermal comfort, two often contradicting demands. The proposed model predictive control system is implemented to control the air-conditioning and mechanical ventilation systems in two single-zone testbeds, an office and a lecture theatre, located in Singapore for experimental evaluation of its control performance. The model predictive control system is compared against the original reactive control system (thermostat in the office and building management system in the lecture theatre) in each testbed. The model predictive control system reduces 58.5% cooling thermal energy consumption in the office and 36.7% cooling electricity consumption in the lecture theatre, as compared to their respective original control. Meanwhile, the indoor thermal comfort in both testbeds is also greatly improved by the model predictive control system. Developing a model predictive control system using machine-learning-based building dynamics models could largely cut down the model construction time to days as compared to its counterpart using physics-based models, which usually take months to construct. However, the machine-learning-based modelling approach could be challenged by lack of building operational data necessary for model training in case of model predictive control development before the building has become operational. Nanyang Technological University This research is financially supported by Energy Research Institute at NTU (ERI@N), JTC Corporation (contract nos. N190107T00 and 2019-0607) and Smart Nation & Digital Government Office (SNDGO) of Singapore (Grant nos. NRF2016IDM-TRANS001-031)

Active chilled beams (ACB) are gaining popularity worldwide as a potentially energy-efficient air-conditioning technology for buildings. However, the control of ACB system is challenging, as it needs to handle multiple cooling coils and the relatively slow response to cooling load dynamics. This paper reports the implementation of a model predictive control (MPC) system for an ACB system, which employs a linear white-box building model for building energy and indoor condition predictions. A multiple-objectives function is employed in the MPC controller to optimize the energy efficiency in air-conditioning system and indoor thermal comfort while fulfilling the constraints of indoor comfort range (−0.5

Model predictive control (MPC) in building automation and control (BAC) applications is challenged by difficulties in constructing accurate building models and handling uncertain disturbances. An adaptive robust model predictive control (ARMPC) is proposed to refine building models and handle uncertainty of disturbances. A model adaptation function is incorporated to perform online estimation of uncertain parameters of the building model using online measured building operation data, as the MPC controller is in operation. An additive uncertainty model to represent uncertainties of disturbances is integrated with the building model for robust optimization. The control performance of the ARMPC is compared with MPC controllers without adaptive modelling and robust optimization, as well as a conventional thermostat through simulation constructed based on a test building. When an energy-saving-biased setting is applied, ARMPC achieves the best thermal comfort performance among the tested controllers. The energy savings achieved by the ARMPC vary from ≈20% to ≈15%, compared to the thermostat, as uncertainty level of internal load increases from 0% to 60%. MPC controllers without adaptive modelling and robust optimization maintain ≈20% energy savings as the uncertainty level increases but at the expense of compromising thermal comfort. When a thermal-comfort-biased setting is applied, the MPC controllers maintain the indoor predicted mean vote (PMV) within a narrow range around thermal neutrality while achieving energy savings of around 10%, compared to the thermostat. The adaptive modelling and robust optimization of the ARMPC prevent the indoor condition from violating the constrains due to model inaccuracy and uncertainties in measured disturbances.

Abnormally low pressure is characteristic of the Mesozoic reservoirs in the Ordos Basin. Based on the study of low pressure distribution, the formation mechanisms of abnormally low pressure were quantitatively analyzed from several aspects, such as tectonic uplift, stratum temperature decrease and dissolution-increased porosity. The Mesozoic reservoir pressure experienced two major evolutionary stages: the pressure rising to maximum pressure stage from the Late Triassic to the Early Cretaceous, the pressure decreasing to abnormally low pressure stage from the end of Early Cretaceous to now. Since the late Early Cretaceous, porosity rebound caused by tectonic uplift, stratum temperature decrease and dissolution caused pressure decrease of up to 20–25 MPa, the decrease ratio is about 54%-77%. The three factors are the main reason for the pressure decrease of the Mesozoic in the Ordos Basin, and among them stratum temperature decrease is the most important factor. Combined with other factors, they made the formation pressure reduced gradually and eventually formed the abnormally low pressure distribution pattern of 10–18 MPa. Key words: abnormally low pressure, tectonic uplift, stratum temperature decrease, dissolution, Yanchang Formation, Mesozoic, Ordos Basin