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Global climate changes, especially the rise of global mean temperature due to the increased carbon dioxide (CO2) concentration, can, in turn, result in higher anthropogenic and biogenic greenhouse gas emissions. This potentially leads to a positive loop of climate–carbon feedback in the Earth’s climate system, which calls for sustainable environmental strategies that can mitigate both heat and carbon emissions, such as urban greening. In this study, we investigate the impact of urban irrigation over green spaces on ambient temperatures and CO2 exchange across major cities in the contiguous United States. Our modeling results indicate that the carbon release from urban ecosystem respiration is reduced by evaporative cooling in humid climate, but promoted in arid/semi-arid regions due to increased soil moisture. The irrigation-induced environmental co-benefit in heat and carbon mitigation is, in general, positively correlated with urban greening fraction and has the potential to help counteract climate–carbon feedback in the built environment.This study shows that urban irrigation is capable of achieving the environmental co-benefit of heat mitigation and carbon neutrality and has the potential to counteract the climate–carbon feedback loop in the U.S. urban environment. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University: Science A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Zhejiang University: Science A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Zhejiang University: Science A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Built terrains, with their complexity in morphology, high heterogeneity, and anthropogenic impact, impose substantial challenges in Earth-system modelling. In particular, estimation of the source areas and footprints of atmospheric measurements in cities requires realistic representation of the landscape characteristics and flow physics in urban areas, but has hitherto been heavily reliant on large-eddy simulations. In this study, we developed physical parametrization schemes for estimating urban footprints based on the backward-Lagrangian-stochastic algorithm, with the built environment represented by street canyons. The vertical profile of mean streamwise velocity is parametrized for the urban canopy and boundary layer. Flux footprints estimated by the proposed model show reasonable agreement with analytical predictions over flat surfaces without roughness elements, and with experimental observations over sparse plant canopies. Furthermore, comparisons of canyon flow and turbulence profiles and the subsequent footprints were made between the proposed model and large-eddy simulation data. The results suggest that the parametrized canyon wind and turbulence statistics, based on the simple similarity theory used, need to be further improved to yield more realistic urban footprint modelling. [ABSTRACT FROM AUTHOR]

As previous study showed that Mycoplasma pneumoniae (MP) induced a cellular immune response associated with interleukin-17 (IL-17), we designed this study to explore IL-17 in MP pneumonia patients with atopic sensitization and 144 patients were evaluated and divided into three groups: atopic MP pneumonia group ( n = 38), non-atopic MP pneumonia group ( n = 74), and atopic non-MP pneumonia group ( n = 32). Serum IL-17 was measured at admission acute phase and at recovery phase. We found IL-17 levels only in the atopic MP pneumonia group that were significantly higher at recovery phase than at acute phase, and its levels were also higher in the atopic MP pneumonia group than the other two groups at clinical recovery phase. In addition, acute asthma attack was higher in the atopic MP pneumonia group. Therefore, IL-17 should be related with asthma and it can be a good marker warning an acute asthma attack in atopic MP pneumonia. Necessary measures can be taken as prevention. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is associated with gastrointestinal motility abnormalities that could favor the occurrence of small intestinal bacterial overgrowth (SIBO). The aim of the study was to assess the prevalence of SIBO in Chinese patients with PD and the potential impact of SIBO on gastrointestinal symptoms and motor function. 182 consecutive Chinese patients with PD patients and 200 sex, age, and BMI-matched subjects without PD were included. All participants underwent the glucose breath test to assess SIBO. We examined the associations between factors and SIBO with logistic regression using SPSS. Fifty-five of the 182 PD patients were SIBO positive (30.2 %; 95 % CI 23.5-36.9 %) compared with 19 of 200 in the control group (9.5 %; 95 % CI 5.4-13.6 %); the difference was statistically significant ( P < 0.0001; OR 4.13; 95 % CI 2.34-7.29). Motor fluctuations present was higher in the PD patients with SIBO than in the patients without SIBO (70.9 vs. 45.7 %; P = 0.002). Multivariate analysis showed that disease duration, Hoehn and Yahr stage, Unified PD Rating-III score, Unified PD Rating-IV score, and Non-Motor Symptoms Scale score were the factors associated with the SIBO-positive status in PD patients. SIBO was highly prevalent in PD, and nearly one-third was detected. SIBO was associated with worse gastrointestinal symptoms and worse motor function. Further studies are needed to specify the reasons underlying SIBO and worse motor function in PD. [ABSTRACT FROM AUTHOR]

A single-layer urban canopy model that captures sub-facet heterogeneity and various hydrological processes is further developed to explicitly incorporate trees within the urban canyon. The physical processes associated with trees are shortwave/longwave radiation exchange, including mutual interception and shading by trees and buildings and multiple reflections, sensible heat and latent heat (through transpiration) exchange, and root water uptake. A computationally-efficient geometric approach is applied to the radiation exchanges, requiring a priori knowledge of view factors. These view factors are first obtained from independent Monte Carlo ray-tracing simulations, and subsequently simple relations, which are functions of canyon aspect ratio and tree-crown ratio, are proposed to estimate them. The developed model is evaluated against field observations at two urban sites and one suburban site, showing improved performance for latent heat flux compared to the previous version that only includes ground vegetation. The trees in the urban canopy act to considerably decrease sensible heat flux and increase latent heat flux, and these effects are found to be more significant in the more dense urban site. Sensitivity tests are then performed to examine the effects of tree geometry relative to canyon geometry. The results indicate that the tree-crown size relative to canyon width is the most influential parameter to decrease sensible heat flux and increase latent heat flux, resulting in cooling of the urban area. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University: Science A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The mechanical properties of AlCoCrFeNi and AlCoCrFeNi high-entropy alloys (HEAs) were investigated by instrumented nanoindentation over a broad range of loading rates. It was found that the loading portion of the two HEAs exhibited apparent discontinuities at low loading rates. However, the discontinuity became less pronounced with increasing the loading rate. The experimental results that the hardness, elastic modulus, and yield strength of AlCoCrFeNi HEAs are larger than those of AlCoCrFeNi HEAs can be elucidated in terms of thermodynamic and topological parameters of the constituent elements and solid solution strengthening, respectively. In situ scanning images displayed a significant pile-up around the indents, demonstrating that a highly localized plastic deformation occurred under nanoindentation. Furthermore, the resistance for creep behavior increases as the Al concentration is increased due to the enlarged lattice distortion related to a solution strengthening effect. [ABSTRACT FROM AUTHOR]

Urbanization modifies surface energy and water budgets, and has significant impacts on local and regional hydroclimate. In recent decades, a number of urban canopy models have been developed and implemented into the Weather Research and Forecasting (WRF) model to capture urban land-surface processes. Most of these models are inadequate due to the lack of realistic representation of urban hydrological processes. Here, we implement physically-based parametrizations of urban hydrological processes into the single layer urban canopy model in the WRF model. The new single-layer urban canopy model features the integration of, (1) anthropogenic latent heat, (2) urban irrigation, (3) evaporation from paved surfaces, and (4) the urban oasis effect. The new WRF-urban modelling system is evaluated against field measurements for four different cities; results show that the model performance is substantially improved as compared to the current schemes, especially for latent heat flux. In particular, to evaluate the performance of green roofs as an urban heat island mitigation strategy, we integrate in the urban canopy model a multilayer green roof system, enabled by the physical urban hydrological schemes. Simulations show that green roofs are capable of reducing surface temperature and sensible heat flux as well as enhancing building energy efficiency. [ABSTRACT FROM AUTHOR]

Unit commitment (UC), as a typical optimization problem in electric power system, faces new challenges as energy saving and emission reduction get more and more important in the way to a more environmentally friendly society. To meet these challenges, we propose a UC model considering energy saving and emission reduction. By using real-number coding method, swap-window and hill-climbing operators, we present an improved real-coded genetic algorithm (IRGA) for UC. Compared with other algorithms approach to the proposed UC problem, the IRGA solution shows an improvement in effectiveness and computational time. [ABSTRACT FROM AUTHOR]

We couple a single column model (SCM) to a cutting-edge single-layer urban canopy model (SLUCM) with realistic representation of urban hydrological processes. The land-surface transport of energy and moisture parametrized by the SLUCM provides lower boundary conditions to the overlying atmosphere. The coupled SLUCM-SCM model is tested against field measurements of sensible and latent heat fluxes in the surface layer, as well as vertical profiles of temperature and humidity in the mixed layer under convective conditions. The model is then used to simulate urban land-atmosphere interactions by changing urban geometry, surface albedo, vegetation fraction and aerodynamic roughness. Results show that changes of landscape characteristics have a significant impact on the growth of the boundary layer as well as on the distributions of temperature and humidity in the mixed layer. Overall, the proposed numerical framework provides a useful stand-alone modelling tool, with which the impact of urban land-surface conditions on the local hydrometeorology can be assessed via land-atmosphere interactions. [ABSTRACT FROM AUTHOR]

The hot deformation behavior of TC18 alloy at strain rates ranging from 1 × 10 to 1 × 10 s and temperatures ranging from 25 to 800 °C was studied using a WDW-300 electronic universal testing machine. The relationships between true stress and true strain show that flow stress decreases with the increase of temperature and increases as strain rate increases. The effect of strain rate on the flow stress becomes pronounced at higher temperatures. At room temperature, the river pattern characteristic of brittle fracture and the dimple pattern typical of ductile fracture are found to exist in different regions of fracture surfaces of the samples. An improved constitutive relationship is proposed to accurately describe the flow stress of TC18 by considering the effect of strain. And a microscopic model is also deduced which can link the physical mechanisms to the macroscopic experimental results. A good agreement is obtained between the predictions of the microscopic model and the results of the macroscopic experiment. [ABSTRACT FROM AUTHOR]

The variations of magnetization and magnetostriction with temperature and stress were investigated through the analysis of the effective field, induced by temperature and stress. A nonlinear magnetostrictive model of giant magnetostrictive materials was proposed. The proposed model can be used to calculate the magnetostrictive characterization of giant magnetostrictive materials in different temperatures and under different stresses. The coupling effects of axial stress, magnetic field, and temperature on the magnetostriction of a Terfenol-D rod were numerically simulated as well as experimentally tested. Comparison between the calculating and experimental results shows that the proposed model can better describe the magneto-thermo-mechanical characteristics of Terfenol-D rod under different temperatures and compressive stress. Therefore, the proposed model possesses an important significance for the design of magnetostrictive devices. [ABSTRACT FROM AUTHOR]

This study aimed to establish a closed-cycle operation technology with high thermal efficiency in the thermochemical sulfur-iodine cycle for large-scale hydrogen production. A series of experimental studies were performed to investigate the occurrence of side reactions in both the HSO and HI phases from the HSO/HI/I/HO quaternary system within a constant temperature range of 323-363 K. The effects of iodine content, water content and reaction temperature on the side reactions were evaluated. The results showed that an increase in the reaction temperature promoted the side reactions. However, they were prevented as the iodine or water content increased. The occurrence of side reactions was faster in kinetics and more intense in the HSO phase than in the HI phase. The sulfur or hydrogen sulfide formation reaction or the reverse Bunsen reaction was validated under certain conditions. [ABSTRACT FROM AUTHOR]

Aim:Fast neuronal network oscillation at the γ frequency band (γ oscillation: 30-80 Hz) has been studied extensively in hippocampal slices under interface recording condition. The aim of this study is to establish a method for recording γ oscillation in submerged hippocampal slices that allows simultaneously monitoring γ oscillation and the oscillation-related intracellular events, such as intracellular Ca2+ concentration or mitochondrial membrane potentials.Methods:Horizontal hippocampal slices (thickness: 300 μm) of adult rats were prepared and placed in a submerged or an interface chamber. Extracellular field recordings were made in the CA3c pyramidal layer of the slices. Kainate, an AMPA/kainate receptor agonist, was applied via perfusion. Data analysis was performed off-line.Results:Addition of kainate (25-1000 nmol/L) induced γ oscillation in both the submerged and interface slices. Kainate increased the γ power in a concentration-dependent manner, but the duration of steady state oscillation was reduced at higher concentrations of kainate. Long-lasting γ oscillation was maintained at the concentrations of 100-300 nmol/L. Under submerged condition, γ oscillation was temperature-dependent, with the maximum power achieved at 29 °C. The induction of γ oscillation under submerged condition also required a fast rate of perfusion (5-7 mL/min) and showed a fast dynamic during development and after the washout.Conclusion:The kainite-induced γ oscillation recorded in submerged rat hippocampal slices is useful for studying the intracellular events related to neuronal network activities and may represent a model to reveal the mechanisms underlying the normal neuronal synchronizations and diseased conditions. [ABSTRACT FROM AUTHOR]

Vasculogenic mimicry (VM), including tubular VM and patterned matrix VM, has been generally recognized as a new pattern of tumor neovascularization. Pilot studies of tubular VM showed that it was present in hepatocellular carcinoma (HCC) and associated with poor clinical prognosis. However, whether patterned matrix VM is clinically significant in HCC is unknown. To elucidate the effects of patterned matrix VM on prognosis of HCC and the mechanisms involved in VM formation, we examined 151 cases of surgically resected human HCC by immunohistochemistry and transmission electron microscopy and conducted hypoxic experiments on human HCC cell line MHCC97-H. We observed 31 of 151 (20.5%) cases exhibited evidence of patterned matrix VM. The expression of patterned matrix VM was associated with larger tumors ( P = 0.042), vascular invasion ( P = 0.016), high-grade HCC ( P = 0.022), and late-stage HCC ( P = 0.013). Kaplan-Meier survival analysis revealed that cases of the VM group had lower overall survival (OS) rate ( P < 0.001) and disease-free survival (DFS) rate ( P = 0.002) than that of the non-VM group. Univariate and multivariate analysis indicated that the presence of patterned matrix VM was independent adverse prognostic factor for both OS ( P = 0.004) and DFS ( P = 0.011). Expression of hypoxia-inducible factor 1 alpha (HIF-1alpha), matrix metalloproteinase (MMP)-2, and MMP-9 were higher in the VM group than in the non-VM group ( P = 0.001, P = 0.030, P = 0.007, respectively). After VM formation was induced by hypoxia, up-regulated expression of HIF-1α, MMP-2, and MMP-9 was also detected in cells cultured under hypoxia condition. Our results indicate that patterned matrix VM exists in HCC, and it might serve as an unfavorable prognostic factor for HCC patients. It is possible that hypoxia via induction of expression of HIF-1alpha, MMP-2, and MMP-9 may enhance VM formation in HCC. [ABSTRACT FROM AUTHOR]

In the urban environment, surface temperatures and conductive heat fluxes through solid media (roofs, walls, roads and vegetated surfaces) are of paramount importance for the comfort of residents (indoors) and for microclimatic conditions (outdoors). Fully discrete numerical methods are currently used to model heat transfer in these solid media in parametrisations of built surfaces commonly used in weather prediction models. These discrete methods usually use finite difference schemes in both space and time. We propose a spatially-analytical scheme where the temperature field and conductive heat fluxes are solved analytically in space. Spurious numerical oscillations due to temperature discontinuities at the sublayer interfaces can be avoided since the method does not involve spatial discretisation. The proposed method is compared to the fully discrete method for a test case of one-dimensional heat conduction with sinusoidal forcing. Subsequently, the analytical scheme is incorporated into the offline version of the current urban canopy model (UCM) used in the Weather Research and Forecasting model and the new UCM is validated against field measurements using a wireless sensor network and other supporting measurements over a suburban area under real-world conditions. Results of the comparison clearly show the advantage of the proposed scheme over the fully discrete model, particularly for more complicated cases. [ABSTRACT FROM AUTHOR]

This study aims to investigate the prognostic factors and long-term treatment outcome in patients with early stage nasal natural killer (NK)/T-cell lymphoma. Sixty-four patients were recruited in this study, whose clinical and laboratory data were collected from hospital records. Early stage (stage IE: 51, stage IIE: 13) nasal NK/T-cell lymphoma (NNTCL) was established according to Ann Arbor staging classification. Among these patients, 23 received radiotherapy (RT) alone, the remaining 41 cases were treated with radiochemotherapy (RCT) comprised of 1–6 cycles of anthracycline-based chemotherapeutic regimens. Results show that the median overall survival (OS) time was 41 months. The 5-year OS and progression-free survival rates were 59.2 and 52.3%, respectively. The 5-year OS rate for patients who received RT alone was 57.9%, whereas that for patients who received RCT was 61.5% ( P = 0.47). There is no significant difference between two treatment modalities. Multivariate analysis showed that Eastern Cooperative Oncology Group performance status (PS) score ≥ 2, local tumor invasion out of nasal cavity, and lower complete remission (CR) rates in the initial treatment were significant unfavorable independent prognostic factors. Taken together, our study suggests that RCT did not improve the survival rate of patients with early stage NNTCL. PS score before treatment, local tumor invasion out of nasal cavity, and CR rate of the primary treatment may be independent prognostic factors among the subtype lymphoma entity. [ABSTRACT FROM AUTHOR]

Rapamycin (RAPA) inhibits tumor growth and angiogenesis in hepatocellular carcinoma (HCC). The molecular mechanism underlying the antitumoral effects of RAPA remains unclear. Here we established a chemical-induced rat HCC model to investigate the signaling pathways mediating RAPA's antitumor activity. We found that RAPA exposure significantly diminished tumor growth, angiogenesis, and metastasis of HCC. Meanwhile, the antitumor drug dramatically decreased expression of HIF-1alpha and VEGF, either at mRNA or protein levels. Moreover, the low-dose of RAPA (1.5 mg/kg/day) was effective enough to markedly inhibit tumor progression of HCC. The preliminary results suggested that the antitumoral effects of RAPA might be at least partially mediated through downregulation of HIF-1alpha and VEGF, and low-dose RAPA-based regimens exhibited a promising future in treatment of HCC. [ABSTRACT FROM AUTHOR]

Reaction mechanisms of SO2 with O3 and H2O2 were investigated using quantum chemistry ab initio methods. Structures of all reactants, products, and transition states were optimized at the B3LYP/6-311G+(3df,2p) level, and energy calculations were made at the G2M level. SO2 reactions with O3 and H2O2 occurred by O-abstraction and OH-abstraction by SO2, respectively, at length forming SO3+O2 (3Σ) and H2SO4. For SO2+O3 reactions the barrier height was predicted to be 9.68 kcal/mol with a rate constant of 3.61×10−23 cm3/(molecule·s) at 300 K, which is below the experimental upper limit. The rate constant predicted for this reaction accords well with the one provided by National Institute for Standards and Technology (NIST) in 250∼500 K. For SO2+H2O2 reactions the barrier height was predicted to be 62.39 kcal/mol with a rate constant of 2.48×10−61 cm3/(molecule·s) at 300 K. [ABSTRACT FROM AUTHOR]

Quantum chemical simulation was used to investigate the catalytic mechanism of Na/K on NO-char heterogeneous reactions during the coal reburning process. Both NO-char and NO-Na/K reactions were considered as three-step processes in this calculation. Based on geometry optimizations made using the UB3LYP/6-31G(d) method, the activation energies of NO-char and NO-Na/K reactions were calculated using the QCISD(T)/6-311G(d, p) method; Results showed that the activation energy of the NO-Na/K reaction (107.9/82.0 kJ/mol) was much lower than that of the NO-char reaction (245.1 kJ/mol). The reactions of NaO/KO and Na2O/K2O reduced by char were also studied, and their thermodynamics were calculated using the UB3LYP/6-31G(d) method; Results showed that both Na and K can be refreshed easily and rapidly by char at high temperature during the coal reburning process. Based on the calculations and analyses, the catalytic mechanism of Na/K on NO-char heterogeneous reactions during the coal reburning process was clarified. [ABSTRACT FROM AUTHOR]

A detailed kinetic model consisting of 126 reactions and 37 species modelled homogeneous low temperature multi-pollutant oxidation in flue gases by ozone. The kinetic model includes the oxidation and chlorination of key flue-gas components, as well as reactions involving SO. An important and previously unrecognized pathway of homogeneous Hg oxidation mechanism includes Hg reactions involving oxygen-containing compounds and chlorine-containing compounds. Analyses by sensitivity simulations revealed that the pathway Hg+Cl=HgCl and HgCl+Cl2=HgCl2+Cl is more significant than some of the key reactions in the kinetic mechanism proposed in the literature except Hg+NO3=HgO+NO2, which indicates the possibility to promote the Hg removal by adding HCl in the inlet stream. Studies on the effects of SO show that SO violently prevents NO consumption through the pathway SO+NO2=NO+SO2, even the net NO produced under the condition of low O3 concentration and high SO concentration. [ABSTRACT FROM AUTHOR]

This paper presents a wideband frequency-shift keying (FSK) demodulator suitable for a digital data transmission chain of wireless neural stimulation microsystems such as cochlear implants and retinal prostheses. The demodulator circuit derives a constant frequency clock directly from an FSK carrier, and uses this clock to sample the data bits. The circuit occupies 0.03 mm2 using a 0.6 μm, 2M/2P, standard CMOS process, and consumes 0.25 mW at 5 V. This circuit was experimentally tested at transmission speed of up to 2.5 Mbps while receiving a 5∼10 MHz FSK carrier signal in a cochlear implant system. [ABSTRACT FROM AUTHOR]

This work proposes a new extraction method for chromium based on the two-phase aqueous system isopropyl alcohol-ammonium sulfate-ammonium thiocyanate ( i-PrOH-(NH4)2SO4-NH4SCN), and the related experimental conditions are optimized. The results show that chromium (III) can be quantitatively extracted under the selected conditions: 4 mL of i-PrOH, 200 μL of 2 mol/L sulfuric acid, 1 mL of 4 mol/L NH4SCN and 3 mL of saturated (NH4)2SO4 solution (Vtotal=10 mL). Application of the proposed method to speciation analysis of plasma chromium was also investigated and satisfactory results were obtained. [ABSTRACT FROM AUTHOR]