[Comparative Study of Clinical Manifestations and Sleep Structure in Children with Obstructive Sleep Apnea-hypopnea Syndrome with Different BMI].

OBJECTIVE: To compare and analyze the clinical manifestations and sleep structure of children with obstructive sleep apnea-hypopneasyndrome (OSAHS) with different body mass index (BMI). METHODS: 452 children who were diagnosed with OSAHS between December 2016 and February 2021 by the Department of Respiratory Medicine, Children's Hospital of Soochow University were included in the study. All of them did polysomnography (PSG). They were divided, according to their BMI, into the normal BMI group, the overweight group, and the obesity group. Their clinical data and PSG results were collected. RESULTS: 287 boys (63.5%) and 165 girls (36.5%) were enrolled, with their age ranging between 3 and 15, and the median age being 5.5 (4.5, 7.0). Their BMI ranged between 12.09 kg/m 2 and 38.48 kg/m 2, with the median being 16.29 kg/m 2. 275 cases (60.8%) had normal BMI, 76 cases (16.8%) were overweight, and 101 cases (22.3%) were obese. There was no significant difference in the distribution of clinical manifestations and severity of OSAHS among the three groups. The duration and proportion of rapid eye movement (REM) stage sleep in the obese group was lower than that of the overweight and the normal BMI groups ( P<0.05). The lowest oxyhemoglobin saturation (LSaO 2) of children in the overweight group was lower than that of the normal BMI group ( P=0.050). The oxygen desaturation index (ODI) of the obese group was higher than that of the normal BMI and the overweight groups ( P<0.05). CONCLUSION: Obesity worsens the degree of hypoxia in children with OSAHS and affects their sleep structure.

[Effects of topographic factors on leaf traits of apricot in the Loess Plateau, Northwest China]. / åœ°å½¢å› å­å¯¹é»„åœŸé«˜åŽŸå±±æå¶ç‰‡åŠŸèƒ½æ€§çŠ¶çš„å½±å“.

As important topographic factors, slope aspect and gradient affect plant growth and leaf functional traits by regulating the combination of water and heat. Exploring the response of leaf functional traits to topographic factors is helpful for understanding plant adaptation strategies. We investigated the effects of sunny slope (including half sunny slope) and shady slope (including half shady slope) and three slope gradient (15°-20°, 21°-25°, and 26°-30°) on the leaf functional traits of apricot (Prunus armeniaca L.), the main afforestation tree species on the Loess Plateau. The results showed that: 1) Slope aspect and gradient exerted significant effects on all functional traits. Except leaf water content (LWC), other leaf functional traits were not affected by the interaction of slope aspect and gradient. 2) The leaf area (LA) under the sunny slope was equivalent to that under the shady slope. Leaf dry matter content (LDMC) and LWC (0.27 g·g-1 and 67.0%, respectively) were significantly higher under the shady slope than under the sunny slope (0.24 g·g-1 and 59.6%, respectively), while specific leaf area (SLA) (163.05 cm2·g-1) was significantly lower under the former than under the latter (183.72 cm2·g-1). 3) At different slope gradients, SLA and LA reached a maximum value at 15°-20° (184.04 cm2·g-1) and 26°-30° (21.14 cm2), respectively. 4) Except no difference in soil water content (Θ) between 15°-20° and 26°-30°, it differed significantly between two slope aspects and among other slope gradients. The Θ was one of the main factors causing the differences in functional traits, especially in the 0-10 cm soil layer. 5) SLA was negatively correlated with LWC and LDW and positively correlated with LA. LDW was positively correlated with LWC and negatively correlated with LA. Θ was positively correlated with LWC but not with other leaf functional traits.

Elevational variations of leaf stochiometry in Leontopodium leontopodioides on the Qinghai-Tibetan Plateau, China.

Topography has major impacts on the trade-off of plant survival strategies. Exploring the differential pattern of leaf ecological stoichiometry along the elevation gradient contributes to a better understanding of plant's response to environmental changes and its ecological adaptability. We investigated leaf C, N, and P concentrations and stoichiometric ratios of Leontopodium leontopodioides at three elevations, including from 4400 m to 4700 m, from 4701 m to 5000 m, and from 5001 m to 5300 m, on the northeastern margin of the Qinghai-Tibetan Plateau in China. The results showed that the concentrations of leaf C, N, and P of L. leontopodioides were 405.36 g·kg-1, 18.42 g·kg-1 and 0.94 g·kg-1, respectively. Leaf C/N, C/P, and N/P were 22.67, 467.61 and 20.30, respectively. The concentrations of leaf N and P of L. leontopodioides consistently increased with the increases of elevation. The coefficient of variations for leaf C, N and P concentrations and ratios of L. leontopodioides were all less than 30%, with an order of P (30%) > C/P (29%) > C/N (18%) > N (17%) > N/P (15%) > C (3%). The growth of L. leontopodioides on the Qinghai-Tibetan Plateau was mainly limited by P availability.

[Effects of grassland management on soil nutrients and their spatial distribution on the Qinghai-Tibetan Plateau, China]. / é’è—é«˜åŽŸè‰åœ°ç®¡ç†æ–¹å¼å¯¹åœŸå£¤å »åˆ†åŠå ¶ç©ºé—´åˆ†å¸ƒçš„å½±å“.

After grasslands were contracted to individual households on the Qinghai-Tibetan Pla-teau, two grassland management patterns were formed, i.e., the single-household management pattern (SMP) and the multi-household management pattern (MMP). The soil nutrients and their spatial distributions under those two patterns were compared in the Nagchu Prefecture of Tibet. The results showed that the soil organic carbon, total nitrogen, and total phosphorus under the MMP (84.31, 6.87 and 0.59 g·kg-1) were all significantly higher than those under the SMP (73.57, 6.07 and 0.54 g·kg-1). On the vertical dimension, the variation coefficient of soil total phosphorous between 0-15 cm layer and 15-30 cm layer under SMP had no significant difference, while that of soil pH, soil organic carbon and total nitrogen in 15-30 cm layer were all higher than 0-15 cm layer under both patterns. On the horizontal dimension, the variation coefficients of soil organic carbon and total nitrogen under SMP were significantly higher than those under MMP, with the estimated values for the former being 25.7% and 23.5%, and for the latter being 19.3% and 18.6%, respectively. Compared with the MMP, the uneven distribution of nutrients could easily lead to soil nutrient loss under the SMP.