A dual-grating InGaAsP/InP DFB laser integrated with an SOA for THz generation

We report a dual-mode semiconductor laser that has two gratings with different periods below and above the active layer. A semiconductor optical amplifier (SOA), which is integrated with the dual-mode laser, plays an important role in balancing the optical power and reducing the linewidths of the emission modes. A stable two mode emission with the 13.92-nm spacing can be obtained over a wide range of distributed feedback and SOA injection currents. Compared with other types of dual-mode lasers, our device has the advantages of simple structure, compact size, and low fabrication cost

Fully integrated multi-optoelectronic synthesizer for THz pumping source in wireless communications with rich backup redundancy and wide tuning range

We report a monolithic photonic integrated circuit (PIC) for THz communication applications. The PIC generates up to 4 optical frequency lines which can be mixed in a separate device to generate THz radiation, and each of the optical lines can be modulated individually to encode data. Physically, the PIC comprises an array of wavelength tunable distributed feedback lasers each with its own electro-absorption modulator. The lasers are designed with a long cavity to operate with a narrow linewidth, typically <4 MHz. The light from the lasers is coupled via an multimode interference (MMI) coupler into a semiconductor optical amplifier (SOA). By appropriate selection and biasing of pairs of lasers, the optical beat signal can be tuned continuously over the range from 0.254 THz to 2.723 THz. The EAM of each channel enables signal leveling balanced between the lasers and realizing data encoding, currently at data rates up to 6.5 Gb/s. The PIC is fabricated using regrowth-free techniques, making it economic for volume applications, such for use in data centers. The PIC also has a degree of redundancy, making it suitable for applications, such as inter-satellite communications, where high reliability is mandatory

Tibetan Dust Accumulation Linked to Ecological and Landscape Response to Global Climate Change

The Tibetan Plateau (TP) is a hotspot of earth system research, and understanding its landscape and ecosystem evolution has been hampered by the lack of time-constrained geological records. Geochronological data from 14 loess sites covering a large region in the Tibetan interior show that the TP loess, rather than accumulating during glacial periods, began aggrading at either 13.4 ± 0.4 or 9.9 ± 0.2 ka. An ecological threshold was crossed, when warmer and wetter conditions resulted in increased vegetation cover enabling dust trapping. This dust accumulation model is out of phase with that of the Chinese Loess Plateau (CLP) where high sedimentation rates occurred during the cold/dry glacial stages. The TP loess accumulation is in response to global climate change, at both orbital (glacial/interglacial) and millennial (e.g., Younger Dryas event) time scales, despite more complexity via ecological and landscape processes than the CLP loess. It is very important to understand the processes of landscape and ecosystem evolution in Tibet to adapt to and mitigate the consequences from potential abrupt future climate changes, but not enough well-dated geological records are available. In this study, we present stratigraphic and numerical age results from 14 loess sites covering a large region in the Tibetan interior. Results show that Tibetan loess began aggrading at either 13.4 ± 0.4 or 9.9 ± 0.2 thousand years ago. Tibetan loess accumulated during warm/interglacial conditions of the Holocene and not during the last glacial period when loess aggradation rates in the Chinese Loess Plateau were high. In Tibet, vegetation cover, which was lowered during the last glacial period, increased during Holocene warming allowing for loess accumulation

Total ginsenosides extract induce autophagic cell death in NSCLC cells through activation of endoplasmic reticulum stress.

ETHNOPHARMACOLOGICAL RELEVANCE(#br)Ginseng (Panax ginseng C. A. Mey) has been widely used in Asian countries for thousands of years. It has auxiliary anticancer efficacy and its derived preparations (e.g. Shenmai injection) are prescribed for cancer patients as Traditional Chinese Medicines clinically in China.(#br)AIM OF THE STUDY(#br)The involved adjuvant anticancer mechanisms of ginseng are still unknown. The present study evaluated the anti-cancer effect of total ginsenosides extract (TGS) and determined the anticancer mechanisms of TGS-induced cell death in human non-small cell lung cancer (NSCLC) cells.(#br)MATERIALS AND METHODS(#br)The anti-cancer effect of TGS was evaluated in NSCLC by cell proliferation assay. The autophagy flux induction of TGS were tested and validated by Western blot, immunofluorescence and transmission electron microscope. The mechanisms of TGS in inducing autophagic cell death were validated by Western blot, gene knockdown and quantitative real time PCR assay.(#br)RESULTS(#br)We found TGS could induce cell death in concentration and time dependent manners, and the cell morphology of NSCLC changed from cobblestone shape to elongated spindle shape after treated with TGS. In the study of cell autophagy, we confirm that TGS could upregulate autophagy flux and induce autophagic cell death through activation endoplasmic reticulum stress. Further investigations demonstrated this process was mediated by the ATF4-CHOP-AKT1-mTOR axis in NSCLC cells.(#br)CONCLUSION(#br)Our findings suggested that TGS could induce autophagic cell death in NSCLC cells through activation of endoplasmic reticulum stress, disclosing another characteristic of TGS-induced cell death and a novel mechanism of TGS and its derived preparations in clinical treatment of cancer patients

Role of Toll-Like Receptor 4 on Lupus Lung Injury and Atherosclerosis in LPS-Challenge ApoE −/−

To investigate the pathologic mechanisms of toll-like receptor 4 (TLR4) in lung injury and atherosclerosis, ApoE−/− or wild-type mice were intraperitoneally administered saline, lipopolysaccharides (LPS), or LPS plus TAK-242 (TLR4 inhibitor), respectively, twice a week for 4 weeks. Serum autoantibody of antinuclear antibody (ANA), anti-double-stranded DNA (anti-dsDNA), and cytokines of interferon-gamma (IFN-γ), tumor necrosis factor (TNF-α), and interleukin-1 (IL-1β) were assessed by ELISA. Hematoxylin and eosin (HE) and Perl's stains for lung pathomorphology as well as HE staining for atherosclerosis were employed. TLR4 in macrophages was detected by double immunofluorescent staining. While protein expressions of TLR4, nuclear factor-kappa B p65 (NF-κB p65), and B cell activating factor belonging to the TNF family (BAFF) were examined by immunohistochemistry. We found that serum autoantibody (ANA and anti-dsDNA), cytokines (IFN-γ, TNF-α, IL-1β), lung inflammation, and intima-media thickness in brachiocephalic artery were obviously increased after LPS challenge in both genotypes, but to a lesser extent in wild-type strains. And those alterations were alleviated by coadministration of LPS and TAK-242. Mechanistically, upregulation of TLR4, NF-κb, and BAFF was involved. We concluded that TLR4/NF-κb/BAFF in macrophages might be a possible common autoimmune pathway that caused lung injury and atherosclerosis. TLR4 signal will be a therapeutic target in atherosclerosis and immune-mediated lung injury

Transcriptome Analysis Reveals Genetic Factors Related to Callus Induction in Barley

Barley is an important cereal crop worldwide. Its genetic transformation is now limited to very few cultivars because of the high genotype dependence of embryogenic callus. To reveal the key genes or factors controlling the callus induction and plantlet regeneration in barley, we compared the transcriptomic profiles of immature embryos of Golden Promise and ZU9, which differed dramatically in the efficiency of the genetic transformation. The samples were taken at 0, 5, 10 and 20 days of the culture, respectively. In total, 5386 up-regulated and 6257 down-regulated genes were identified in Golden Promise. Several genes, identified exclusively in GP callus, were selected for further investigation. These genes were mainly involved in protein metabolism, energy metabolism, stress response, detoxification and ubiquitin–proteasome. Four YUCCA flavin monooxygenases, one PIN-FORMED, one tryptophan aminotransferase related, three small auxin up RNA, three indole-3-acetic acid and one adenylate isopentenyl transferase, seven cytokinin oxidase/dehydrogenase, three Arabidopsis histidine kinase, three Arabidopsis histidine phosphotransfer protein, and one Arabidopsis response regulator were differentially expressed in the calli of the two barley genotypes, suggesting that biosynthesis, response and transport of auxin and cytokinin might be associated with cell reprogramming during callus induction. The current results provide insights into molecular mechanisms of callus induction at an early developmental stage and are helpful for optimizing the tissue culture system in barley

Prevalence and risk factors of frailty among people in rural areas: a systematic review and meta-analysis

Objective Older people in rural areas are possibly more frail due to the limited medical resources and lower socioeconomic status. Given the negative healthy outcomes caused by frailty, knowing the epidemiology of frailty in rural areas is of great importance. We tried to synthesise the existing evidences for the prevalence and risk factors of frailty in rural areas.Design A systematic review and meta-analysis.Data sources PubMed, Embase, MEDLINE, Cochrane Library, Web of Science and Scopus were used to identify the articles from inception to 30 April 2019.Eligibility criteria Observational studies providing cross-sectional data on the prevalence of frailty in rural elderly were extracted.Data extraction and synthesis Two independent investigators selected studies, extracted data and assessed the methodological quality of included studies. The pool prevalence of frailty was calculated by the random effects model and the OR and 95% CI were used to calculate the risk factors.Results The literature search yielded 2219 articles, of which 23 met the study criteria and were included in this analysis. The pooled prevalence of frailty and pre-frailty were 18% (95% CI 15% to 21%, I2=98.5%, p<0.001) and 50% (95% CI 45% to 56%, I2=98.4%, p<0.001), respectively. The pooled frailty prevalence was 15% for the Fried Phenotype, 18% for the Frailty Index and 23% for other criteria. The pooled prevalence of frailty was 17% for males and 26% for females. The pooled prevalence of frailty was 17% in developing countries and 23% in developed countries. Age, cognitive impairment, depressive symptom, risk of malnutrition, activity of daily living (ADL) disability and poor self-perception of health were associated with frailty. There was no publication bias.Conclusions Frailty influences almost one in five older people in rural areas, and increasing age, cognitive impairment, depressive symptom, risk of malnutrition, ADL disability and poor self-perception of health were all risk factors for frailty. We should be cautious about the research results due to the heterogeneity between studies

Early father-infant skin-to-skin contact and its effect on the neurodevelopmental outcomes of moderately preterm infants in China: study protocol for a randomized controlled trial

Abstract Background Skin-to-skin contact (SSC) is an evidence-based intervention that benefits low birth weight /preterm infants. However, China’s health institutional policy inhibits parents from visiting their baby in the neonatal intensive care unit (NICU). In addition, the Chinese traditional postpartum behavioral practice of confining women to home raises barriers to mother-infant contact. Thus, to shorten the duration of parent-infant separation, father-infant SSC is considered a possible alternative. This study determines whether it is safe to perform father-infant SSC in the NICU and investigates how paternal SSC affects outcomes compared with traditional care (TC) for moderately preterm infants. Methods/design A randomized controlled trial will be used to investigate the effects of paternal-infant SSC in NICU wards in China. Preterm infants born at a gestational age in the range of 320–346 weeks with a birth weight > 1500 g will be eligible. A simple random sampling method will be used to allocate infants to the SSC group (n = 25) or the TC group (n = 25). After medical stability, infants in the SSC group will be provided SSC by fathers for one hour every day until discharged from hospital. The primary outcome is neurodevelopmental measures, specifically salivary cortisol and Premature Infant Pain Profile (PIPP) during hospitalization. At 40 weeks of corrected age, infants will be assessed using the Infant Neurological International Battery (INFANIB) and neuroimaging. Secondary outcomes include infants’ physiological stability during SSC and throughout hospitalization and state observation at discharge. The fathers’ mental health will be assessed with the State-Trait Anxiety Inventory (STAI) 1 day to 3 days after the infant’s admission to the NICU and at discharge. Father-infant attachment will be evaluated at 4 and 6 months after the infants’ discharge, measured by the Paternal Postnatal Attachment Scale (PPAS). Statistical analyses will be conducted using a two-sided significance level of 0.05. Discussion The effects of paternal-infant SSC on moderately preterm infants will be assessed. The data gathered in this study may have important implications for medical practice and policy in the NICU regarding the care methods of premature infants in China. Trial registration Chinese Clinical Trial Registry, ChiCTR-IOR-1701274. Registered on 20 September 2017. Retrospectively registered

The Choquet integral with respect to a level dependent capacity

We present a generalization of Choquet integral in which the capacity depends also on the value of the aggregated variables.We show that as particular cases of our generalization of Choquet integral there are the Sugeno integral, theŠipoš integral and the CPT functional