Extreme temperature is strongly associated with human health, but few studies are available for the effects of extreme temperatures on respiratory disease (RD) in rural villages in Jiuquan, China ...over 2018–2019. In this study, we evaluate the effect of daily mean temperature on RD hospitalizations in suburban rural villages. A distribution lag non-linear model was constructed to analyze the relationship between the temperature and the daily risk of RD hospitalizations; and stratified analysis by sex and age group was performed. The effect of daily mean temperature on RD hospitalizations was non-linear and lagging. With a reference 25th percentile of temperature (−1.8 °C), exposure to extremely low temperature (−15.8 °C, 1st percentile), or moderate low temperature (−8.3 °C, 10th percentile) were associated with 1.396 (95% CI: 1.251, 1.558) and 1.216 (95% CI: 1.180, 1.253) increased risks of RD hospitalizations over lag 0–21 days. For RD morbidity, the effects of moderate high temperature (90th percentile of temperature, 22.5 °C) appeared at on the exposed day (lag 0), with the largest hot effect (RR 1.008, 95% CI 1.001, 1.020), while the effects of extremely high temperature (99th percentile of temperature, 27.0 °C) were insignificant. The effect of ambient temperature varied with gender and age. Both cold and high temperatures have more serious influence on males than females. In contrast, the elderly (age ≥ 65) seemed to be more sensitive in extremely low temperature (RR = 3.471; 95% CI, 2.183, 5.518; lag 0–21). The effect of moderate high temperature on the < 65 years group appeared for the first time at lag 0 (RR = 1.012; 95% CI, 1.001, 1.029). Both high temperature and low temperature increased the RD hospitalization risk; the harmful effect and duration of low temperature were greater than that of high temperature; the ≥ 65-year group and male were more sensitive to low temperature.
The present study is a theoretical investigation into the structural evolution, electronic properties, and photoelectron spectra of phosphorus-doped boron clusters PBn0/− (n = 3–17). The results of ...this study revealed that the lowest energy structures of PBn− (n = 3–17) clusters, except for PB17−, exhibit planar or quasi-planar structures. The lowest energy structures of PBn (n = 3–17), with the exceptions of PB7, PB9, and PB15, are planar or quasi-planar. The ground state of PB7 has an umbrella-shaped structure, with C6V symmetry. Interestingly, the neutral cluster PB15 has a half-sandwich-like structure, in which the P atom is attached to three B atoms at one end of the sandwich, exhibiting excellent relative and chemical stability due to its higher second-order energy difference and larger HOMO–LUMO energy gap of 4.31 eV. Subsequently, adaptive natural density partitioning (AdNDP) and electron localization function (ELF) analyses demonstrate the bonding characteristics of PB7 and PB15, providing support for the validity of their stability. The calculated photoelectron spectra show distinct characteristic peaks of PBn− (n = 3–17) clusters, thus providing theoretical evidence for the future identification of doped boron clusters. In summary, our work has significant implications for understanding the structural evolution of doped boron clusters PBn0/− (n = 3–17), motivating further experiments regarding doped boron clusters.
•Degradation and restoration influence runoff and sediment by distinct pathways.•Degradation altered “high runoff - low sediment” to “high runoff - high sediment”.•Restoration reduces sediment yield, ...although sediment concentration increases.•Surface runoff is crucial to sustain downstream river flow in the QTP.
Artificial grassland is considered an effective measure for restoring severely degraded grassland in alpine areas and has been widely applied on the Qinghai-Tibetan Plateau. However, the specific effects of artificial restoration and degradation on slope runoff and sediment yield are still poorly understood. In this study, we investigated the effects of artificial restoration and degradation on the runoff sediment process in three areas: an alpine meadow (AM), a severely degraded alpine meadow (BL), and a degraded alpine meadow that was restored by artificial grassland (AG). Our findings revealed that the runoff in AG was significantly lower than that in both AM and BL, with reductions by 95.59% and 88.40%, respectively. The sediment yield in AG was significantly reduced, with reductions by 21.77% and 90.54% compared to AM and BL, respectively. Nevertheless, the sediment concentration in AG was 27.22 and 3.26 times higher than that in AM and BL, respectively. Our study provides clear evidence that plant and soil properties play a crucial role in driving soil erosion processes in both AG and BL. Specifically, artificial grassland was effective in inhibiting runoff and sediment yield. This inhibition was attributed to the modification of soil conditions and the interception of rainfall, which were facilitated by the recovery of vegetation coverage and the increased input of organic matter. These findings have significant implications for the artificial restoration of degraded alpine meadows and soil erosion prevention efforts on the Qinghai-Tibetan Plateau.
This paper addresses a multicircular circumnavigation control for UAVs with desired angular spacing around a nonstationary target. By defining a coordinated error relative to neighboring angular ...spacing, under the premise that target information is perfectly accessible by all nodes, a centralized circular enclosing control strategy is derived for multiple UAVs connected by an undirected graph to allow for formation behaviors concerning the moving target. Besides, to avoid the requirement of target’s states being accessible for each UAV, fixed-time distributed observers are introduced to acquire the state estimates in a fixed-time sense, and the upper boundary of settling time can be determined offline irrespective of initial properties, greatly releasing the burdensome communication traffic. Then, with the aid of fixed-time distributed observers, a distributed circular circumnavigation controller is derived to force all UAVs to collaboratively evolve along the preset circles while keeping a desired angular spacing. It is inferred from Lyapunov stability that all errors are demonstrated to be convergent. Simulations are offered to verify the utility of proposed protocol.
Earth to air heat exchangers are widely utilized to cool or heat passive buildings for energy savings. They often need to deal with high humidity air conditions, especially in the greenhouse due to ...plant transpiration, and the condensation phenomenon is frequently observed during the cooling process. To evaluate the effect of humidity and condensation on thermal performance, a three dimensional computational fluid dynamic (3D-CFD) model was developed. The distribution of relative humidity in each pipe was investigated, and the impact of inlet air relative humidity on the integrated performance of the earth to air heat exchanger was discussed. The effects of inlet air temperature and volume flow rate were also analyzed. Moreover, the influence of the heat exchanger configurations on the performance of the air condensation was researched. The results indicated that condensation had few effects on the airflow distribution uniformity of the earth to air heat exchanger, while it acted observably on the thermal performance. In addition, humid air in a small diameter pipe tended to condense more easily. Humidity and condensation should be taken into consideration for the design of earth to air heat exchangers in greenhouses during engineering applications.
Artificial intelligence (AI), as a significant feature of modern development, has changed the form of education, especially with a significant impact on higher education (HE). Clarifying the ...integration and infiltration of HE and AI is of great significance for the future development of AI in HE. The Citespace is used to make a quantitative and qualitative analysis of the indicators such as authors, institutions, nationalities, disciplines, journals, and highly cited articles of AI research literature -located at HE included in the Web of Science core collection database. The results show that in recent years, AI in the field of HE has received extensive international attention, and the research results are in a growing trend. In the field of international HE, AI focuses on hot topics such as parameter design, deep learning, machine learning human-computer interaction and hybrid learning. And deep learning, learning space simulation design, learning effectiveness measurement, etc. will become an important development direction of international AI research in the field of HE.
Prostate cancer (PCa) is the second most common cancer in men, causing more than 300,000 deaths every year worldwide. Due to their superior cell-killing ability and the relative simplicity of their ...preparation, immunotoxin molecules have great potential in the clinical treatment of cancer, and several such molecules have been approved for clinical application. In this study, we adopted a relatively simple strategy based on a single-domain antibody (sdAb) and an improved Pseudomonas exotoxin A (PE) toxin (PE24X7) to prepare a safer immunotoxin against prostate-specific membrane antigen (PSMA) for PCa treatment. The designed anti-PSMA immunotoxin, JVM-PE24X7, was conveniently prepared in its soluble form in an Escherichia coli (E. coli) system, avoiding the complex renaturation process needed for immunotoxin preparation by the conventional strategy. The product was very stable and showed a very strong ability to bind the PSMA receptor. Cytotoxicity assays showed that this molecule at a very low concentration could kill PSMA-positive PCa cells, with an EC50 value (concentration at which the cell viability decreased by 50%) of 15.3 pM against PSMA-positive LNCaP cells. Moreover, this molecule showed very good killing selectivity between PSMA-positive and PSMA-negative cells, with a selection ratio of more than 300-fold. Animal studies showed that this molecule at a very low dosage (5 × 0.5 mg/kg once every three days) completely inhibited the growth of PCa tumors, and the maximum tolerable dose (MTD) was more than 15 mg/kg, indicating its very potent tumor-treatment ability and a wide therapeutic window. Use of the new PE toxin, PE24X7, as the effector moiety significantly reduced off-target toxicity and improved the therapeutic window of the immunotoxin. The above results demonstrate that the designed anti-PSMA immunotoxin, JVM-PE24X7, has good application value for the treatment of PCa.
Cr(VI) and Mn(VII) in industrial wastewater have certain toxicity, and they pose a threat to the environment and human health and safety. Metal–organic frameworks (MOFs) usually have rich ...adsorption sites and a large specific surface area. They can effectively adsorb Cr(VI) and Mn(VII) from wastewater. In this paper, a two-dimensional copper-based metal–organic framework, {Cu·(4,4′-bpy)2·(H2O)·2(NO3)·6(H2O)·(CH3OH)} n (1), is synthesized by hydrothermal synthesis. The structure of 1 is characterized by Fourier transform infrared (IR) spectroscopy, single-crystal X-ray diffraction, element analysis, and X-ray photoelectron spectroscopy (XPS). The results showed that 1 had a two-dimensional network structure, and the specific surface area of the nanostructure was 67.63 m2/g. The nanostructure of 1 could efficiently adsorb Cr(VI) and Mn(VII) from wastewater. The adsorption properties of Cr(VI) and Mn (VII) of 1 showed that the optimal concentration of both adsorbents was 0.2 g/L. It has good adsorption performance in the pH range 4–8. The adsorption performance is the best when pH is 7, which can reach 145 and 83 mg/g, respectively.
To reduce the phosphorus content in steel, the CaO–SiO2–FexO–MgO-based dephosphorization slag was designed to clarify the microscopic reaction behavior of phosphorus. In the present study, Raman ...spectra of final slag were measured and deconvoluted. The spectral analysis showed that P5+ ions removed from liquid iron existed in the form of Q0(P) and Q1(P) groups. According to the result, phosphate capacity and phosphorus distribution ratio (LP*) were redefined. The results showed that lgLP* was proportional to molar ratio of Q0(P)/Q1(P), indicating that Q0(P) exerted a significant influence on LP* compared with Q1(P). As the increases of CaO/SiO2 from 0.15 to 1.25 and FeO from 7.2 to 21.9 mass% in the final slag, lgLP* gradually increased, whereas lgLP* showed a downward trend when FeO increased to 29.2 mass%. This was because the increase of O2− ions generated by the dissociations of CaO, MgO and FeO continuously destroyed the network structure and formed more Q0(P) units, which were compensated by the increasing Ca2+, Mg2+, and Fe2+ cations to form stable groups. Meanwhile, the Q0(Si) units formed by slag depolymerization further played a role in fixing Q0(P). However, due to the stronger polarization of Fe2+ than Ca2+ and Mg2+, Q0(P) and Q1(P) units were easily deformed and decomposed by Fe2+. The excessive Fe2+ diluted the proportion of Ca2+ and Mg2+, and made Q0(P) and Q1(P) lose stability. The P5+ ions in the Q0(P) and Q1(P) units were reduced to liquid iron, and the rephosphorization phenomenon occurred, resulting in a decrease of lgLP*.
In order to avoid the disadvantages of the Fenton process in wastewater treatment and reduce the cost of wastewater treatment, a series of MIL-101(Fe)-X (X = −OH, −NH2, −NO2, −H) solid Fenton ...catalysts were successfully prepared. The performance of these Fenton-like catalysts was studied with the Fenton experiment as a reference and methylene blue (MB) as an organic pollutant. The effects of the H2O2 concentration, catalyst dosage, and reaction pH on catalytic performance were systematically studied. The research had shown that the optimal concentration of H2O2 for catalytic reactions was 0.10 mmol/L and the pH was 3. At this point, their catalytic degradation MB performance was superior to the Fenton reaction and photocatalytic reaction. When the H2O2 participated in the reaction, the performance of MIL-101(Fe)-X (X = −OH, −NH2, −NO2, −H) in catalyzing the degradation of MB followed the rule of −OH > −NH2 > −NO2 > −H. This was due to the synergistic effect of Fenton-like catalysis and photocatalytic degradation in the catalytic degradation of MB. In addition, the electron paramagnetic resonance and electrospray ionization mass spectrometry showed that the hydroxyl radical (·OH) generated during the catalytic process first underwent a redox reaction with the highly electronegative functional groups in the MB molecule, and finally oxidized it to CO2 and H2O. This study successfully prepared commercially applicable Fenton-like catalysts and explored their optimal reaction conditions. This provides a technical reference for wastewater treatment.
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