Characteristics and source apportionment of black carbon the urban and desert underlying surfaces.

The spatial distribution of black carbon (BC) concentrations was highly variable across different underlying surfaces. Differences in meteorological conditions and emission sources led to great temporal and spatial variations in BC characteristics. As the most important absorbing aerosol, BC can affect radiation, clouds, and surface snow. BC mass concentrations were measured using a seven channel aethalometer (AE-33) in the Urumqi and Taklimakan Deserts from January to December 2022. The aethalometer data, potential source contribution function (PSCF), and concentration-weighted trajectory (CWT) models were used to analyse the variation characteristics, potential sources, and affected areas. Results showed that the BC concentrations in the Taklamakan Desert and Urumqi were in the range of 0-500 ng·m-3, accounting for 66.20 % and 59.50 % of the total, respectively. The backward trajectory simulation of BC mass concentration in the tower and Urumqi using the HYSPLIT model found that the airflow trajectories in the tower in summer corresponded to the BC concentration in the following order: trajectory 4 > trajectory 3 > trajectory 2 > trajectory 1, and trajectory 4 originated from the Turpan airflow accounting for 46.19 % of the total, which corresponded to the highest BC concentration of 621.73 ng·m-3. The trajectories of the airflow in Urumqi in summer corresponded to the BC concentration in the order of high to low, and the BC concentration in summer corresponded to the highest concentration in the Turpan airflow. BC concentrations arranged from high to low were trajectory 1 > trajectory 5 > trajectory 3 > trajectory 4 > trajectory 2. Trajectories 3, 4, and 5 airflow directions were the same, and the airflow trajectory accounted for 47.48 %, corresponding to BC concentrations of 599.82 ng·m-3, 579.99 ng·m-3, and 555.85 ng·m-3, respectively. Tower in the spring compared with other seasons of the CWT value of >400 ng·m-3 had the widest coverage, and Urumqi had more source areas contributing to moderate pollution concentration weights in winter (400 ng·m-3 < CWT < 800 ng·m-3). The conclusions of this study provide a scientific basis for regional environmental management and the formulation of air pollution measures in Xinjiang.

Clinical Effect of Modified Jichuanjian on Senile Patients with Slow Transit Constipation of Spleen-kidney Yang Deficiency Syndrome and Effect on Brain-gut Peptide / 中国实验方剂学杂志

ObjectiveTo observe the clinical effect of modified Jichuanjian on senile patients with slow transit constipation of spleen-kidney yang deficiency syndrome and the influence on brain-gut peptide. MethodA total of 150 senile patients with slow transit constipation were randomized into control group （75 cases） and observation group （75 cases） with the random number table method. The observation group was given modified Jichuanjian （oral， 1 dose/day， 4 weeks）， and the control group was treated with Biantong Capsules （oral， 3 capsules/time， twice/day， 4 weeks）. Data before and after treatment were recorded， including the score of major constipation symptoms， score of Patient Assessment of Constipation Quality of Life （PAC-QOL）， TCM syndrome score， spontaneous complete bowel movements （SCBM）， colonic transit test， serum 5-hydroxytryptamine （5-HT）， 5-HT 4 receptor （5-HT4R）， somatostatin （SS）， and vasoactive intestinal peptide （VIP）， and recurrence. ResultThe total effective rate of the observation group was 93.06% （67/72）， as compared with the 74.65% （53/71） in the control group （χ2=8.974 6， P<0.01）. After treatment， the scores of major constipation symptoms， scores of four dimensions of PAC-QOL， total score of PAC-QOL， and TCM syndrome score were lower than those before treatment in the two groups （P<0.01）， and lower in the observation group than in the control group （P<0.01）. The SCBM in the observation group were more than those in the control group at the 2nd， 3rd， 4th weeks after treatment （P<0.01）. The proportions of residual markers at 24， 48， 72 h after treatment were smaller than those before treatment in the two groups （P<0.01）， and smaller in the observation group than in the control group （P<0.01）. After treatment， the levels of serum 5-HT and 5-HT4R were higher （P<0.01） and the levels of serum SS and VIP were lower （P<0.01） than those before treatment in the two groups. In addition， the levels of serum 5-HT and 5-HT4R in the observation group were higher （P<0.01） and the levels of serum SS and VIP were lower （P<0.01） in the observation group than in the control group. The recurrence in the observation group was 29.85% （20/67） in comparison with the 58.49% （31/53） in the control group （χ2=9.932 4， P<0.01）. ConclusionModified Jichuanjian is effective for senile patients with slow transit constipation of spleen-kidney yang deficiency syndrome， which can alleviate clinical symptoms， improve quality of life， regulate the level of serum brain-gut peptide， improve the colonic transit function， increase SCBM， and reduce the recurrence.