Mobile social media use and life satisfaction among adolescents: a moderated mediation model.

Introduction: Adolescence is a sensitive transitional period accompanied by great physical, mental, and behavioral changes. Therefore, maintaining physical and mental health is crucial to the growth and development of adolescents. As one of the important indicators of mental health, the influencing factors of life satisfaction have been widely concerned by scholars. In recent years, with the rapid development of Internet technology, mobile social media has penetrated into all aspects of adolescents' life, which has a subtle impact on their physical and mental health. Existing studies have indicated that mobile social media use can affect adolescents' life satisfaction. However, little is known about the mediating and moderating mechanisms linking this association. This study developed a moderated mediation model to examine the mediating role of meaning in life and the moderating role of childhood psychological maltreatment. Methods: A total of 1,198 adolescents across four provinces and municipalities of China completed questionnaires on mobile social media use, life satisfaction, meaning in life, and childhood psychological maltreatment. Results: After controlling for gender and age, the results demonstrated that mobile social media use was positively associated with life satisfaction and meaning in life among adolescents. Moreover, meaning in life fully mediated the association between mobile social media use and life satisfaction. Finally, the association between mobile social media use and life satisfaction, as well as that between mobile social media use and meaning in life, was moderated by childhood psychological maltreatment. Specifically, these associations are stronger for adolescents with high levels of psychological maltreatment. Discussion: These findings shed light on the important mechanism underlying mobile social media use's effects on adolescents' life satisfaction, which is helpful to formulate targeted measures for improving adolescents' life satisfaction.

First complete mitochondrial genome of Rhodinia species (Lepidoptera: Saturniidae): genome description and phylogenetic implication.

To explore the characteristics of the mitochondrial genome (mitogenome) of the squeaking silkmoths Rhodinia, a genus of wild silkmoths in the family Saturniidae of Lepidoptera, and reveal phylogenetic relationships, the mitogenome of Rhodinia fugax Butler was determined. This wild silkmoth spins a green cocoon that has potential significance in sericulture, and exhibits a unique feature that its larvae can squeak loudly when touched. The mitogenome of R. fugax is a circular molecule of 15,334 bp long and comprises 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and an A + T-rich region, consistent with previous observations of Saturniidae species. The 370-bp A + T-rich region of R. fugax contains no tandem repeat elements and harbors several features common to the Bombycidea insects, but microsatellite AT repeat sequence preceded by the ATTTA motif is not present. Mitogenome-based phylogenetic analysis shows that R. fugax belongs to Attacini, instead of Saturniini. This study presents the first mitogenome for Rhodinia genus.

Method of fiber transfer delay measurement based on phase quantization and delay synthesis.

A novel method, to the best of our knowledge, of fiber transfer delay (FTD) measurement based on phase quantization and delay synthesis is proposed and demonstrated. By detecting the differential phase shifts of a set of frequency-multiplied RF signals transmission through the fiber link with and without the FTD under the test, the ${2}\pi $2π phase ambiguity problem can be solved. To avoid the phase quantization error near the digital quantization boundary, a self-check and error-correction method is proposed so as to greatly improve the reliability of measurement. In the experiment, the measurement repeatability around 0.018 ps within a period of 80 s is achieved for a back-to-back fiber link, and a test resolution of 0.03 ps is proved with a motorized tunable delay line. The system is available for measurement of a large FTD range up to 100 µs with no dead zone.

Tunable OEO-based photonic RF receiver with image frequency rejection.

A tunable optoelectronic oscillator (OEO)-based photonic radio frequency (RF) heterodyne receiver with the capability of image frequency rejection is proposed and experimentally demonstrated. The OEO incorporating a dual-electrode Mach-Zehnder modulator (DEMZM) operates as a high quality local oscillator (LO) and a broadband mixer simultaneously, with one electrode port of the DEMZM used for the feedback of the generated LO signal and the other port for receiving external RF signals. Two channels of immediate frequency (IF) signals can be achieved in optical domain by beating the +1-order sideband of LO with the +1-order sideband of input RFs and beating the -1-order sideband of LO with the -1-order sideband of input RFs correspondingly. Through setting the bias angle of the DEMZM at π/4 or 5π/4 and quadrature combining of the two channels of the IF signal, the combined IF signal down-converted from the target RF signal gets enhanced due to the in-phase sum of two channels, while the combined IF signal down-converted from the image frequency can be rejected due to out-of-phase sum of two channels. In the experiment, the input RF signals with operating frequency range from 8.85 to 14.85 GHz are successfully received with the image rejection ratio reaching 42.6 dB, and the spurious free dynamic range of the system is better than 94.8 dB Hz2/3.

Highly sensitive demodulation of a vibration-induced phase shift based on a low-noise OEO.

A highly sensitive demodulation approach of a vibration-induced phase shift based on a low-noise optoelectronic oscillator (OEO) is proposed and experimentally demonstrated. The vibration-induced optical phase variation is directly converted to the electrical oscillating signal of the OEO with carrier phase-shifted double-sideband (CPS-DSB) modulation, which is realized by cascading a dual-output Mach-Zehnder modulator (DOMZM) and a fiber interferometer. Theoretically, within a CPS-DSB modulated OEO, the minimum detectable optical phase shift is determined by the phase noise achievable, and the sensitivity of the optical phase shift demodulation no longer depends on its frequency. A proof-of-concept OEO oscillating at 100 MHz with ultralow phase noise is built for demonstration. The achieved minimum detectable optical phase shift is 0.58 µrad/√Hz at 1 kHz and 0.21 µrad/√Hz at 10 kHz, which are the best results ever reported, to the best of our knowledge.

Frequency-dependent noise figure analysis of continuous photonic time-stretch system.

In this paper, the frequency-dependent noise figure of a continuous photonic time-stretch system is theoretically analyzed and experimentally demonstrated. Mathematic analysis discloses that the frequency-dependent noise figure in the continuous photonic time-stretch system is mainly owing to the dispersion-induced phase shift in the link. In the experiment, a completely continuous signal is reconstructed with time-interleaved joining of four sections of time-stretched signals from optical wavelength-division de-multiplexing channels. The result of the frequency-dependent noise figure property agrees well with that of theoretical analysis.

[Morphology and pathogenesis of 47, XYY/47, XY, +mar identified in patients with super male syndrome].

OBJECTIVE: To explore the source and morphology of supernumerary markers from patients with 47,XYY/47,XY, +mar and supermale syndrome. METHODS: Conventional GTG banded karyotyping and dual-color fluorescence in situ hybridization (FISH) were performed on 21 such patients. RESULTS: Among these cases, 18 had their small supernumerary marker derived from the Y chromosome. Three were derived from autosomal chromosomes. Those derived from Y chromosome were small fragments with centromeres, while those derived from autosomes were in the ring form. CONCLUSION: In children with supermale syndrome and 47,XYY/47,XY,+ mar, the supernumerary marker chromosomes primarily derive from sex chromosomes. These small chromosomes mainly have the forms of small segments with centromeres or rings. For such children, molecular cytogenetic analysis can facilitate genetic counseling and prenatal diagnosis.

ß-catenin knockdown enhances the effects of fluorouracil in the breast cancer cell line MDA-MB-468.

Tumor proliferation, drug resistance and cell stemness are major difficulties that are encountered during breast cancer therapy and are often responsible for disease progression and cancer-related mortality. ß-catenin is considered to be an invasion gene in breast cancer. However, how ß-catenin regulates breast cancer cell proliferation and stemness remains unclear. In the present study, ß-catenin knockdown by small interfering RNA in MDA-MB-468, a highly metastatic breast cancer cell line, inhibited the expression of ß-catenin, Oct3/4 (stemness), survivin (anti-apoptosis) and BCRP (drug resistance). Knockdown of ß-catenin enhanced the effects of fluorouracil (5-FU) chemotherapy on the proliferation of MDA-MB-468 cells. Thus, these preliminary results indicate that ß-catenin knockdown enhanced 5-FU-induced proliferation inhibition in the breast cancer cell line MDA-MB-468, and indicate that combining 5-FU with gene silencing could be an advantageous option for enhancing the curative effect of chemotherapy in breast cancer and other malignancies.

[Identification of a novel splicing mutation in COL1A1 gene in a Chinese family affected with typeâ osteogenesis imperfecta].

OBJECTIVE: To investigate the genetic cause for a large family affected with typeⅠosteogenesis imperfecta. METHODS: Genomic DNA was extracted from peripheral venous blood samples. The entire coding region and intron-exon boundaries of the COL1A1 gene were subjected to PCR amplification and direct sequencing. Total RNA was also extracted from immortalized B cell lines from the patients, with the first strand of cDNA synthesized with an oligo(dT)18 primer. The PCR products were directly sequenced using the TA cloned plasmid. RESULTS: A c.3208G>A mutation has been identified in the COL1A1 gene, which can alter the splicing pattern of mRNA. CONCLUSION: A novel splicing mutation c.3208G>A of the COL1A1 gene probably underlies the disease.

Empowering village doctors and enhancing rural healthcare using cloud computing in a rural area of mainland China.

BACKGROUND: China's healthcare system often struggles to meet the needs of its 900 million people living in rural areas due to major challenges in preventive medicine and management of chronic diseases. Here we address some of these challenges by equipping village doctors (ViDs) with Health Information Technology and developing an electronic health record (EHR) system which collects individual patient information electronically to aid with implementation of chronic disease management programs. METHODS: An EHR system based on a cloud-computing architecture was developed and deployed in Xilingol county of Inner Mongolia using various computing resources (hardware and software) to deliver services over the health network using Internet when available. The system supports the work at all levels of the healthcare system, including the work of ViDs in rural areas. An analysis done on 291,087 EHRs created from November 2008 to June 2011 evaluated the impact the EHR system has on preventive medicine and chronic disease management programs in rural China. RESULTS: From 2008 to 2011 health records were created for 291,087 (26.25%) from 1,108,951 total Xilingol residents with 10,240 cases of hypertension and 1152 cases of diabetes diagnosed and registered. Furthermore, 2945 hypertensive and 305 diabetic patients enrolled in follow-up. Implementing the EHR system revealed a high rate of cholecystectomies leading to investigations and findings of drinking water contaminated with metals. Measures were taken to inform the population and clean drinking water was supplied. CONCLUSIONS: The cloud-based EHR approach improved the care provision for ViDs in rural China and increased the efficiency of the healthcare system to monitor the health status of the population and to manage preventive care efforts. It also helped discover contaminated water in one of the project areas revealing further benefits if the system is expanded and improved.

[A case-control family study of gastric cancer in Henan province].

OBJECTIVE: To explore the risk factors of gastric cancer in the rural area of Henan province. METHODS: Three hundred and twenty-five families with gastric cancer and 325 control families (1010 persons in each group) were selected among the rural residents in 4 counties of Henan province. Totally 2020 people were surveyed and assessed using population-based case-control family study. RESULTS: Gastric cancer was related to stomach upset, irregular dietary, hobby for salty taste, residual food, and history of mental stimulus. CONCLUSION: Stomach upset, irregular dietary, hobby for salty taste, residual food, and history of mental stimulus are the risk factors of gastric cancer.

[Chemical characteristics of nitrogen and phosphorus in the sediments of the typical bays in Dianchi Lake and calculation of their dredging layers].

The sediments of Haidong bay and Macun bay in Dianchi Lakes' experimental area were studied. The sediment column was cut in every 3cm, and the following items are tested, such as total phosphorus, phosphorus species, which include labile phosphate, Fe,Al-P, Ca-P and residual-P, total nitrogen, nitrate nitrogen, nitrite nitrogen, ammonium nitrogen. The results showed that the loads of nitrogen and phosphorus of these two bays increased quickly in recent years. The Fe, Al-P was the largest component in all the P-forms and the content of ammonium nitrogen in these two bays less than that of other lakes. The layer of 9 to 12 centimeters of the two bays was polluted less than the rests. It indicated that these years more and more wastewater was inflow in these two bays. At the same time, the distribution of each testing items showed another low value between 24 to 39 centimeters. So considering feasibility and economic restriction, we can set the 24 - 39 centimeters depth as a dredging layer.