Association between excessive screen time and falls, with additional risk from insufficient sleep duration in children and adolescents, a large cross-sectional study in China.

Objective: Falls is a major global public health issue that occur in all age groups. However, the association between screen time, sleep duration and falls in children and adolescents remains unclear.

Methods: This study included children and adolescents who participated in the 2017 Nutrition and Health Surveillance of Children and Lactating Mothers in China.

The work challenges faced by primary healthcare workers in Guangzhou during the COVID-19 pandemic prevention and control period of 2021-2022: a qualitative study.

Background: Primary healthcare workers in China were vital in controlling COVID-19, facing unprecedented challenges due to the pandemic's suddenness and transmissibility. This paper analyzed their work in Guangzhou, highlighting key difficulties in past epidemic control efforts.

Methods: Semi-structured qualitative interviews were conducted with selected primary healthcare workers in Guangzhou City and audio-recorded until saturation of themes was reached.

Job burnout and its influencing factors among primary healthcare workers during the COVID-19 epidemic in Guangzhou, China, 2021-2022: from the perspective of institutional operation and management.

Background: The purpose of this study was to explore the job burnout of primary healthcare workers in Guangzhou during the prevention and control of COVID-19 epidemic and its influencing factors from the perspective of institutional operation and management in 2021-2022.

Methods: A cross-sectional study involved 866 primary healthcare workers from different districts of Guangzhou, China. The Chinese version of the Maslach Burnout Inventory-General Survey (MBI-GS) was utilized to assess job burnout.

Chemical mutagenesis of a GPCR ligand: Detoxifying "inflammo-attraction" to direct therapeutic stem cell migration.

A transplanted stem cell's engagement with a pathologic niche is the first step in its restoring homeostasis to that site. Inflammatory chemokines are constitutively produced in such a niche; their binding to receptors on the stem cell helps direct that cell's "pathotropism." Neural stem cells (NSCs), which express CXCR4, migrate to sites of CNS injury or degeneration in part because astrocytes and vasculature produce the inflammatory chemokine CXCL12.

[Evaluation of the color stability of infiltrant resin in comparison to aesthetic composite resins].

Objective: To investigate the color stability of infiltrant resin together with three other composites exposed to staining solution.

Methods: Three types of anterior aesthetic composite resins (Filtek Z250, Filtek Z350 XT, and Beautiful Flow Plus F00) and artificial caries with Icon infiltrant resin were used. The samples were randomly divided into two groups (each contained 10 specimens): coffee solution and distilled water immersion for three weeks.

[A clinical study of Palodent posterior teeth matrix system].

Objective: To set up a clinical evaluation method for the matrix system, and compare two matrix systems, Palodent and circumferential, by this method.

Methods: 101 molars and premolars with class II cavities, which were suitable for resin filling without shift and incline of the adjacent teeth, were randomly divided into study group (Palodent) and control group (circumferential). There were 79 single cavities and 22 paired cavities.

Sequence and analysis of rice chromosome 4.

Rice is the principal food for over half of the population of the world. With its genome size of 430 megabase pairs (Mb), the cultivated rice species Oryza sativa is a model plant for genome research. Here we report the sequence analysis of chromosome 4 of O.

A fine physical map of the rice chromosome 4.

As part of an international effort to completely sequence the rice genome, we have produced a fine bacterial artificial chromosome (BAC)-based physical map of the Oryza sativa japonica Nipponbare chromosome 4 through an integration of 114 sequenced BAC clones from a taxonomically related subspecies O. sativa indica Guangluai 4 and 182 RFLP and 407 expressed sequence tag (EST) markers with the fingerprinted data of the Nipponbare genome. The map consists of 11 contigs with a total length of 34.