2016~2017年广西6~17岁儿童青少年营养状况及膳食质量评价

目的了解2016~2017年广西6~17岁儿童青少年营养状况,并利用中国健康膳食指数(China Diet Index,CHDI),评价其膳食质量,为后续开展营养干预工作提供依据。方法选用2016~2017年中国儿童与乳母营养健康项目广西监测点中,737名具有完整3 d 24 h的膳食调查和体格测量数据的6~17岁儿童青少年,计算体质指数和CHDI得分,评价其营养状况及膳食质量。结果广西6~17岁儿童青少年生长迟缓率为1.09%,消瘦率为3.80%,超重率为6.65%,肥胖率为4.88%。随着年龄的增加,超重率和肥胖率存在上升趋势(P<0.05)。汉族的超重率为8.75%,高于壮族及其他民族的4.15%(P=0.013)。从地区上看,大城市超重率(17.14%)最高(P<0.001),大城市和中小城市的肥胖率均高于其他地区,分别为8.57%和9.84%(P<0.001)。广西儿童青少年膳食质量合格的比例仅为7.60%,相较于男性,女性的CHDI得分更高(P=0.015)。相较于壮族及其他民族,汉族的CHDI得分更高(P=0.002)。不同地区CHDI得分由高到低依次为,大城市、中小城市、贫困农村、普通农村(P<0.001)。在CHDI各指标中,精制谷物(94.30%)、肉蛋类(94.17%)、纯食物能量供能比(85.07%)达标率较高,而水果类(5.97%)、钠(2.71%)、食物种类(1.22%)、饱和脂肪酸供能比(0.14%)达标率较低。结论广西儿童青少年营养不良得到改善,超重率、肥胖率较高,总体膳食质量较差,膳食营养素摄入不均衡,且存在民族和地区差异,需加大营养干预力度,做好健康饮食的宣传教育工作。

Gorenstein flatness and injectivity over Gorenstein rings

Let R be a Gorenstein ring.We prove that if I is an ideal of R such that R/I is a semi-simple ring,then the Gorenstein flat dimension of R/I as a right R-module and the Gorenstein injective dimension of R/I as a left R-module are identical.In addition,we prove that if R→S is a homomorphism of rings and SE is an injective cogenerator for the category of left S-modules,then the Gorenstein flat dimension of S as a right R-module and the Gorenstein injective dimension of E as a left R-module are identical.We also give some applications of these results.

Applications of balanced pairs

Let(X, Y) be a balanced pair in an abelian category. We first introduce the notion of cotorsion pairs relative to(X, Y), and then give some equivalent characterizations when a relative cotorsion pair is hereditary or perfect. We prove that if the X-resolution dimension of Y(resp. Y-coresolution dimension of X)is finite, then the bounded homotopy category of Y(resp. X) is contained in that of X(resp. Y). As a consequence, we get that the right X-singularity category coincides with the left Y-singularity category if the X-resolution dimension of Y and the Y-coresolution dimension of X are finite.

The socle of the last term in a minimal injective resolution

Let Λ and Γ be left and right Noetherian rings and Λ U a generalized tilting module with Γ = End( Λ U ). For a non-negative integer k, if Λ U is (k - 2)-Gorenstein with the injective dimensions of Λ U and U Γ being k, then the socle of the last term in a minimal injective resolution of Λ U is non-zero.

The Auslander-type condition of triangular matrix rings

Let R be a left and right Noetherian ring and n, k be any non-negative integers. R is said to satisfy the Auslander-type condition Gn（k） if the right fiat dimension of the （i ＋ 1）-th term in a minimal injective resolution of RR is at most i ＋ k for any 0 ≤ i ≤ n - 1. In this paper, we prove that R is Gn（k） if and only if so is a lower triangular matrix ring of any degree t over R.