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With urbanization, the influx of populations into economically developed large- and medium-sized cities, and the reality of high property prices are forcing the rental housing market to expand. The population, economy, and housing rental market interact, and the coordinated development of the three systems is an inevitable requirement for sustainable urban development. To coordinate the relationship between population, economy, and the housing rental market in large and medium-sized cities, it is crucial to solve the housing problem and achieving "housing for all so that everyone can live and work happily". Based on coupling coordination and spatial error models, this study explores the level of coupling coordination of the population-economy-housing rental market system in thirty-five large and medium-sized cities across China in 2018-2019, and explores its influencing factors. The results show the following: (1) As three social systems, the population, economy, and housing rental market interact with each other. In the perspective of sustainable urban development, the harmonious development between the three systems is a rational movement of population, a well-functioning economy and a smoothly functioning housing rental market, where the three systems win and prosper together. (2) Among the 35 large and medium-sized cities, the integrated population level and economic subsystems are on an upward trend; the integrated housing rental market level has slightly decreased, and although the integrated evaluation value of the housing rental market in the eastern core cities is higher, it still lags behind the population and economy development. (3) Considering the time, the difference in the development of the coupling and coordination degree of the population-economy-housing rental market system of each city has become more extensive. Still, the overall trend is upward, and the coupling and coordination degree of cities classified as pilot housing rental cities are relatively high. (4) For space, there are significant differences in the degree of coupling and coordination of the population-economy-housing rental market system between regions. The degree of coupling coordination in eastern cities is generally higher than in other regions; Shanghai and Beijing have reached a substantial coordination level. Among the central cities, the coupling coordination of Zhengzhou and Changsha remains at the primary coordination level, the coupling coordination of Wuhan rises to the primary coordination level, and the coupling coordination of the other cities is mainly at the barely coordinated level. There is a wide gap in the coupling coordination between cities among western cities. The coupling coordination of Chongqing is at the primary coordination level, of Xi'an and Urumqi is at the barely coordinated level, and of Chengdu has increased from the slightly coordinated level to the primary coordination level. The coupling coordination of other western cities is at the verge of dissonance, except for the cities mentioned above. The coupling coordination degree of all four cities decreased slightly in the northeast region, while Harbin dropped to the near-disordered level. (5) The level of economic development, population size, level of development of the real estate market, and educational resources are notable factors in increasing the level of coupling and coordination of the system. This study analyzes the coupling and coordination between population, economy, and the housing rental market in 35 large and medium-sized cities in China from the coordinated development perspective. This enriches the housing rental market research and alternatively provides a reference for decision-making to address the housing problem in large and medium-sized cities in China and achieve "housing for all".

To investigate the seasonal variation, health risks, and potential sources of polycyclic aromatic hydrocarbons(PAHs) in PM 2.5 in the Lüliang area, PM 2.5 samples were collected in Lishi District(downtown area) and Xiaoyi City(suburban area) from October 23, 2018 to July 1, 2019, and the concentrations of 14 PAHs were determined using gas chromatography-mass spectrometry(GC-MS). The annual average concentration of PAHs was 95.50 ng·m -3 , and the concentration of 5-6 ring PAHs was mainly(49.7%), with 3 ring PAHs accounting for a relatively low proportion(8.3%).The concentration of PAHs in Lüliang City showed a seasonal pattern of winter>autumn>spring>summer. The results of the ILCRs model and Monte Carlo simulation showed that the toxicity of PAHs in Lüliang City followed the rule of adults>youth>children. Except in summer, the ILCRs values in the Lishi area were between 10 -6 and 10 -4 , much higher than those in Xiaoyi City, indicating that there was a high potential risk of polycyclic aromatic hydrocarbons in the urban area. Through the characteristic ratio method and positive matrix factorization(PMF), it was shown that the PAHs in Lüliang City were mainly from the combustion of coal and biomass(61.9%) and vehicle exhaust emissions(38.1%). Based on the backward trajectory and potential source factor contribution analysis model, it was determined that the potential sources of PAHs in Lüliang City were mainly distributed in southern Shanxi, northern Shaanxi, and western Inner Mongolia.

In order to investigate the pollution characteristics and sources of elements in PM 2.5 in the Shanxi University Town in 2017, an energy dispersive X-ray fluorescence spectrometer (ED-XRF) was used to analyze 21 kinds of elements in PM 2.5 samples. A health risk assessment was conducted for Mn, Zn, Cu, Sb, Pb, Cr, Co, and Ni. The main sources of elements were identified by the principal component analysis (PCA) and positive matrix factorization (PMF). The results found that, among the 21 kinds of elements in PM 2.5 in Shanxi University Town, the mass concentration of Ca was the highest, followed by Si, Fe, Al, S, K, and Cl. These seven elements accounted for 95.71% of the total element concentrations. The concentration of Cr exceeded the annual average concentration limit of ambient air quality standards in China by 104 times. The concentration of Ca in PM 2.5 was the highest in spring, summer, and winter, while in autumn the concentration of S was the highest. Mn was the element that had non-carcinogenic risks to the three population types, and the level of risks were in the order of children > adult men > adult women. Cr and Co had tolerable carcinogenic risks, and the risk levels were in the order of adult men > adult women > children. The main sources of elements in PM 2.5 in Shanxi University Town in 2017 were natural mineral dust, urban dust, coal combustion, and traffic.

Objective: To observe the effect of Schistosoma japonicum cysteine protease inhibitor (rSjCystatin) for treatment of lipopolysaccharide (LPS)-induced sepsis in mice., Methods: After a week of adaptive feeding, 54 BALB/c mice were randomly divided into normal control group (group A), sepsis group (group B), and rSjCystatin intervention group (group C). The mice in group A received an intraperitoneal injection of PBS (100 µL), and those in groups B and C were injected with PBS (100 µL) containing LPS (10 mg/kg); the mice in group C were also intraperitoneally injected with 25 µg sjCystatin in 100 µL PBS 30 min after LPS injection. From each group, 10 mice were randomly selected 24 h after PBS or LPS injection for detecting serum levels of TNF-α, IL-6, and IL-10 using ELISA and the levels of ALT, AST, BUN, and Cr using automatic biochemical analyzer; the pathological changes in the liver, lung and kidney were observed with HE staining. The remaining 8 mice in each group were used for observing the changes in the general condition and the 72-h survival., Results: The 72-h survival rates of the mice was 100% in group A, 0 in group B, and 36% in group C, showing a significant difference among the 3 groups (P<0.05). Compared with those in group A, the mice in group B exhibited obvious liver, lung, and renal pathologies with increased levels of ALT, AST, BUN, Cr, IL-6, and TNF-α (P<0.05). Treatment with sjCystatin significantly lessened LPS-induced organ pathologies, lowered the levels of liver and renal functional indexes and the pro-inflammatory cytokines, and increased the serum level of IL-10 in the mice (P<0.05)., Conclusion: SjCystatin can produce a significant therapeutic effect on sepsis induced by LPS in mice.

Samples of particulate sources in Yuncheng including road dust, salt lake dust, coal dust, soil dust, construction,cement dust and vehicle exhaust dust were collected. Elements, ions and carbon species in particulate sources samples were analyzed. Enrichment factors and potential ecological risk assessment were used to analyze the characteristics of road dust, and chemical mass balance model was applied to identify the source of road dust. The results showed that, compared with other cities, the proportions of Na(12.1970%) and SO 4 2- (8.5971%) were relatively high while that of Si(9.1123%) was low in road dust in Yuncheng, and enrichment factors showed that the sources of Pb, Cu, Cr, V, As, Ni, Na and Zn in road dust were obviously influenced by human activities; the potential ecological risk of heavy metals in road dust was high, which was affected by anthropogenic sources such as industrial production, the combustion of fossil fuels and vehicle exhaust; the profiles of coal dust, vehicle exhaust dust, construction and cement dust were similar to those of other cities, the Na and SO 4 2- concentrations in soil dust were relatively high, and the proportions of Na and SO 4 2- in salt lake dust were 30.3% and 22.7% respectively; salt lake dust was the largest contributor (53%) to road dust, followed by the soil dust (21%), vehicle exhaust dust (8%), construction and cement dust (7%), and coal dust (5%).

The ashes under dust catcher of typical power plants in Yangquan was collected and the contents of elements, irons, EC (elemental carbon) and OC (organic carbon) were measured in PM₂. The characteristics of its chemical composition was studied and the degree of similarity of coal dust's source profiles of PM₂.₅ between Yangquan and other cities were compared using the coefficient of divergence method. The result indicated that the main chemical components of PM₂.₅ from the coal dust were SO₄²⁻,Ca, NO₃⁻, OC, EC, Al, Si, Na, Fe, Mg and Cl⁻, accounting for 57.22% of the total mass. The enrichment factor of Pb in PM₂.₅ of coal dust was the largest with a significant enrichment condition, reaching 10.66-15.91. The coefficient of divergence of source profiles of PM₂.₅ between blind coal and fault coal was 0.072, so it was believed that they must be similar. Compared with other cities, the chemical composition of coal dust in Yangquan had specificity, in particular, the content of Ca was obviously higher than those in other domestic cities.

In order to make effective plan to provide the scientific basis for prevention and control of re-suspended dust (RD), samples of particulate sources including RD and other pollution sources of Jincheng were collected. Elements, ions and carbon in particulate sources were analyzed. Enrichment factor, potential ecological risk assessment, and chemical mass balance model were used to analyze the chemical composition and the source of RD. The result indicated that the main components in RD of Jingeheng were Si, TC, Ca, OC, Al, Mg, Na, Fe, K and SO4(2-), contributing 61.14% of total mass of RD. The most abundant content of RD was crustal elements, and the ions were enriched in the fine particles. The mass fraction of OC in PM2. was higher, whereas the mass fraction of EC in PM10 was higher, indicating that secondary organic pollutants were mainly dominated in the fine particles. The dust PM2.5 and PM10 potential ecological risk indexes were extremely strong, and PM2.5 had higher ecological harm than PM10. Pb had the highest enrichment factor of 196.97 in PM2.5, which was followed by As, Cr, Ni, V, Zn and Cu, the enrichment factors of which were all greater than 10, indicating that they were apparently enriched and affected by human activities. Soil dust, construction dust, vehicle exhaust, and coal dust were the main sources of RD.

Based on rice, wheat, corn straw and rape, broad bean green stalk as the research object, using phospholipid fatty acid (PLFA) method, combining principal component analysis method to study the soil microbial quantity, distribution of flora, community structure characteristics under dry and water farming as two different cultivated land use types. The PLFA analysis results showed that: under dry farming, total PLFA quantity ranged 8.35-25.15 nmol x g(-1), showed rape > broad bean > corn > rice > wheat, rape and broad bean significantly increased total PLFA quantity by 1.18 and 1.08 times compared to the treatment without straw; PLFA quantity of bacterial flora in treatments with straws was higher than that without straw, and fungal biomass was significantly increased, so was the species richness of microbial community. Under water faming, the treatments of different straws returning with landfill have improved the PLFA quantity of total soil microbial and flora comparing with the treatment without straw, fungi significantly increased, and species richness of microbial communities value also increased significantly. Total PLFA quantity ranged 4.04-22.19 nmol x g(-1), showed rice > corn > wheat > broad bean > rape, which in rape and broad bean treatments were lower than the treatment without straw; fungal PLFA amount in 5 kinds of straw except broad bean treatment was significantly higher than that of the treatment without straw, bacteria and total PLFA quantity in broad bean processing were significantly lower than those of other treatments, actinomycetes, G+, G- had no significant difference between all treatments; rice, wheat, corn, rape could significantly increase the soil microbial species richness index and dominance index under water faming. The results of principal component analysis showed that broad bean green stalk had the greatest impact on the microbial community structure in the dry soil, rape green stalk and wheat straw had the biggest influence on soil microbial community structure in water soil.

PM2.5 samples were collected at four sampling sites in Shuozhou during the heating and non-heating periods. Organic carbon (OC) and elemental carbon (EC) in PM2.5 were analyzed by Elementar Analysensysteme GmbH vario EL cube and the concentration, spatial and temporal distribution characteristics and main sources of OC and EC were studied. The results were as following: average concentrations of OC and EC in PM2.5 during non-heating period were (14.3 ± 2.7) μg x m(-3) and (10.3 ± 3.1) μg x m(-3) while (23.3 ± 5.9) μg xm(-3) and (20.0 ± 5.7) μg x m(-3) during heating period. The concentrations of OC and EC at four sites during the heating period were higher than those during the non-heating period. The concentrations of OC and EC at SW site during heating were the highest which were 28.5 μg x m(-3) and 28.1 μg x m(-3) while the concentrations at PS sites during non-heating period were the highest, which were 17.7 μg x m(-3) and 14.1 μg x m(-3). The ratios between OC and EC during the heating and non-heating period were all below 2 and the correlation between OC and EC was not good with R2 of 0. 66 during heating period and 0.52 during non-heating period which indicated that sources of carbon aerosols were complex. Carbonaceous aerosol pollution should be reduced by controlling the primary emissions such as coal combustion, vehicle exhaust and biomass burning, and by paying attention to secondary pollution at the same time to improve the air quality in Shuozhou City. The concentrations of SOC during heating and non-heating period were (6.44 ± 2.77) μg x m(-3) and (4.11 ± 1.92) μg x m(-3).

PM10 samples were collected at four sampling sites to study pollution characteristics of carbonaceous aerosols in Xinzhou during heating period (March) and non-heating period (July), 2011. Organic carbon (OC) and elemental carbon (EC) in PM10 were analyzed by Elementar Analysensysteme GmbH vario EL cube, and the characteristics including pollution levels, temporal and spatial distributions of OC and EC as well as OC/EC ratios were investigated in detail. The results were as following: OC and EC mass concentrations of PM10 in Xinzhou were (18.5 +/- 4.5) microg x m(-3) and (16.1 +/- 4.3) microg x m(-3), respectively. The concentrations of total carbon aerosol (TCA) accounted for 70.7% of PM10 during the heating period, and 43.8% during the non-heating period. The concentrations of OC at four sites during the heating period were higher than those during the non-heating period, and this trend was consistent with that of EC concentrations except for SQ site, which indicated coal combustion was a dominant source of OC and EC during the heating period. OC concentration at XT site and EC concentration at DC site were the highest, which were 24.1 microg x m(-3) and 22.0 microg x m(-3) respectively, while the concentrations of OC and EC at SQ site were both the lowest, which were 17.2 microg x m(-3) and 14.5 microg x m(-3), respectively, which indicated that the spatial distributions of OC and EC were obviously different. The average values of OC/EC ratios were all below 2, which indicated that the primary pollution was predominant. The correlation between OC and EC during the non-heating period was good with R2 of 0.55, indicating the emission sources were consistent and the vehicle exhaust played an important role, while the correlation was weak during the heating period (R2 = 0.13), which revealed that the emission sources of OC and EC were complicated. Carbonaceous aerosol pollution should be reduced by controlling the primary emissions such as coal combustion, vehicle exhaust, biomass burning and other industrial sources to improve the air quality in Xinzhou City.

The n-alkanes in PM10 and typical emission sources samples collected during heating and non-heating periods in Taiyuan were determined with GC-MS. Meanwhile, the distribution characteristics and source identification of n-alkanes were investigated with diagnostic parameters and principal component analysis (PCA). Concentrations of n-alkanes ranged from 213.74 to 573.32 ng.m-3 and 22.69 to 150.82 ng.m-3 in the heating and non-heating seasons, respectively. The n-alkanes concentrations in suburban districts including JY, JCP, XD and SL were higher than those in urban sites in the heating quarter, and the relative concentration in JS was 7 times higher than that in SL in the other period. The correlation of the total n-alkanes in PM10 with that derived from fossil fuel was higher than the correlation with those from plant in the heating quarter, while the opposite result was detected in the other period, manifesting higher contribution of fossil fuel in the heating days. CPI and % WNA values showed that the contribution from plant wax in the non-heating period was higher than that in the heating period, and the alkanes production rate was elevated along with the increase in environmental pressures. Information on higher organic matter maturity was obtained during the heating period by Cmax and OEP and the existence of UCM bulge confirmed that vehicles were the significant contributor to n-alkanes concentration during the whole year. PCA analysis indicated the major component was the mixture of vehicle emission and higher plant, accounting for 51.28% of the total variances, followed by coal dust, accounting for 43. 14%. Cooperating control of emissions from coal combustions and vehicles would be the effective way to lower the concentrations of the corresponding n-alkanes.

In order to investigate the characteristic of organic carbon (OC) and elemental carbon (EC) in particles on the top of coke oven and in the plant area, the particle matter samples of five size fraction including < or = 1.4 microm, 1.4-2.1 microm, 2.1-4.2 microm, 4.2-10.2 microm and > or = 10.2 microm were collected using Staplex234 cascade impactor, and OC and EC were analyzed by Elementar Analysensysteme GmbH vario EL cube. The mass concentrations of OC and EC associated with TSP on the top of coke oven were 291.6 microg x m(-3) and 255.1 microg x m(-3), while those in the plant area were 377.8 microg x m(-3) and 151.7 microg x m(-3). The mass concentration of secondary organic carbon (SOC) in particles with size of < or = 1.4 microm was 147.3 microg x m(-3) in the plant area. The value of OC/EC in particles less than 2.1 microm was 1.3 on the top of coke oven. The mass concentration of EC in TSP in the plant area was lower than that on the top of coke oven, while the mass concentration of OC in the plant area was significantly higher than that on the top of coke oven. The mass concentrations of OC and EC associated with particles less than 10.2 microm in the plant area were far higher than those in the atmosphere of area where the coke plant is located. The OC and EC in particles, which were collected both on the top of coke oven and in the plant area, were mainly enriched in fine particles. The size distribution of OC showed a clear distinction between the coke oven top and the plant area, which revealed that OC in the plant area was more preferably enriched in fine particles than that on the top of coke oven, and the same size distribution of EC was found on the top of coke oven and in the plant area. In the plant area, the mass concentration of SOC and the contribution of SOC to OC increased with the decreasing diameter in particles with diameter of less than 10.2 microm.

In order to investigate the characteristics of polycyclic aromatic hydrocarbons (PAHs) in ashes from coking, PAHs in ashes from three coke production plants were analyzed with GC-MS, and the distribution characteristics of PAHs and potential toxicity risk were discussed. The sum of 16 EPA prior PAHs varied from 8.17 x 10(2) to 5.17 x 10(3) microg x g(-1). PAH contents from the coke oven (stamp charging) with the height of 3.2 m were two times higher than those from the one (top charging) with the height of 6.0 m, and PAHs in ashes from coal charging were significantly higher than those from coke pushing in the same plant. Four-ring and five-ring PAHs were the dominant species in ashes from coking and the sum of them accounted for more than 80.00% of total PAHs. Chrysene (Chr), benzo [a] anthracene (BaA) and benzo [b] fluoranthene (BbF) were abundant in all ash samples. The content of total BaP-based toxic equivalency (BaPeq) ranged from 1.64 x 10(2) to 9.57 x 10(2) microg x g(-1). From the carcinogenic point of view, besides benzo [a] pyrene (BaP), dibenz [a,h] anthracene (DbA) contributed most to the overall toxicity of PAHs, followed by BaA and BbF. BaPeq concentration from coal charging was 5.21-fold higher than that from coke pushing, indicating that different reuse ways should be considered based on their specific toxicity profiles of PAHs.

This paper is aimed to investigate the signal source and influential factors in signals of trans-esophageal pulse oxygen saturation (SeO2). The red light of the SeO2 probe was faced directly to the descending aorta (DA) of the mongrel dogs. The readings and waveform of SeO2 signals were recorded under following conditions: before and after DA was shield; before and after the blood supply of esophagus was cut off; under the different touch pressures between the SeO2 probe and the esophageal wall. The readings and waveform of SeO2 signals were also recorded respectively at both different esophageal depth and directions when mechanical ventilation was on and off. The tongue oxygen saturation (StO2) was recorded simultaneously as control. The waveform of SeO2 signals disappeared after DA was shield (P < 0.001). No significant difference was found in the SeO2 signals before and after the blood supply of esophagus was cut off (P > 0.05). Compared with the StO2 readings when the SeO2 probe was placed at different esophageal depth, the waldeyer ring, cervical area and thoracic inlet,the readings of SeOz significantly decreased (P < 0.05) while mechanical ventilation was on and off. However, there was no significant difference in the readings between SeO2 signals from DA, aortic arch (AA) and left subclavian artery and the StO2 signals recorded simultaneously. Mechanical ventilation had a remarkable effect on the SeO2 signals at different esophageal depth (P < 0.05), but the StO2 signals lay in its insensitivity to its influence. The readings of StO2 signals were significantly different from that of StO2 signals when the touch pressure between the SeO2 probe and the esophageal wall below 40 mmHg (P < 0.01). The directions of the optimum SeO2 signals acquired at different esophageal depth were not the same. The SeO2 signals were primarily derived from deeper arteries around the esophagus. All of Mechanical ventilation, location of the SeO2 probe in the esophagus and the touch pressure between the probe and esophageal wall can influence SeO2 signals.

Objective: To investigate the source and factors that influence tracheal pulse oximetry signal., Methods: The adult mongrel dog was intubated after anesthesia. The tracheal tube was modified by attaching a disposable pediatric pulse oximeter to the cuff. The chest of the dog was cut open and a red light from the tracheal oximeter was aligned with the deeper artery. The changes in tracheal pulse oxygen saturation (SptO2) signal were observed after the deeper artery was blocked temporarily. The photoplethysmography (PPG) and readings were recorded at different intracuff pressures. The influence of mechanical ventilation on the signal was also tested and compared with pulse oxygen saturation (SpO2)., Results: The SptO2 signal disappeared after deeper artery was blocked. The SptO2 signal changed with different intracuff pressures (P < 0.001). Stronger SptO2 signal appeared under 20-60 cm H2O of intracuff pressure than under 0-10 cm H2O of intracuff pressure(P < 0.001). The PPG of SptO2 signal under a condition with mechanical ventilation differed from that without mechanical ventilation (P < 0. 01), which, was also different from SpO2 (P < 0.01)., Conclusion: SptO2 signal is primarily derived from deeper arteries around the trachea, not from the tracheal wall. Both intracuff pressures and mechanical ventilation can influence SptO2 signal. The SptO2 signal under 20-60 cm H2O of intracuff pressure is stronger than that under 0-10 em H2O of intracuff pressure. Mechanical ventilation mainly changes PPG.

Objective: To plan and develop a Chongqing chemical accident rescue command system., Methods: Based on the modes of leakage and diffusion of various poisonous gases and chemicals, different modes of injuries produced, and their appropriate rescue and treatments, also taking the following factors such as the condition of storage of chemicals, meteorological and geographic conditions, medical institutions and equipment, and their rescuing capacity into consideration, a plan was drafted to establish the rescue system. Real-time simulation technology, data analysis, evaluation technology and database technology were employed in the planning. Using Visual Studio 6.0 as the software development platform, this project aimed to design the software of an emergency command system for chemical accidents in Chongqing which could be operated with the Windows 2000/XP operating system., Results: This system provided a dynamic scope of the endangered area, casualty number estimates, and recommendation of measures and a rescue plan for various chemical accidents. Furthermore, the system helped retrieve comprehensive information regarding the physical and chemical characteristics of more than 4 200 dangerous poisonous chemicals and their appropriate treatment modalities., Conclusion: This system is easy to operate with a friendly interface, functions rapidly and can provide real-time analysis with comparatively precise results. This system could satisfy the requirements of executing the command and the rescue of a chemical accident with good prospects of application.

Objective: To investigate the effect of daphnetin on superoxide dismutase (SOD) activity and DNA synthesis in P. falciparum in vitro., Methods: The effect of daphnetin, daphnetin-Fe complex and desferrioxamine B on SOD activity of P. falciparum (P.f) FCC1 in vitro was determined with a SOD test-kit. The level of DNA synthesis of P.f synchronized cultured in vitro at various developmental stages after treatment of daphnetin or desferrioxamine B was assayed by fluorescein Hoechest 33258., Results: The total SOD activity decreased by 60% after daphnetin treatment while it only decreased by 22% if treated with desferrioxamine B. No effect on SOD activity of P.f treated with daphnetin-Fe complex was observed. The level of DNA synthesis of P.f trophozoites in synchronized in vitro culture was significantly lower than that of the control., Conclusion: Daphnetin lowered SOD activity and decreased DNA synthesis of P.f in vitro.