A PDM-based 128-Gb/s PAM4 fibre-FSO convergent system with OBPFs for polarisation de-multiplexing.

A polarisation-division-multiplexing (PDM)-based four-level pulse amplitude modulation (PAM4) fibre-free-space optical (FSO) convergent system with optical band-pass filters (OBPFs) for polarisation de-multiplexing is feasibly demonstrated for the first time. In a PDM scenario with PAM4 modulation, the transmission capacity of fibre-FSO convergent systems is enhanced four times with an aggregate channel capacity of 128 Gb/s (64 Gb/s PAM4/polarisation × 2 polarisations). With an OBPF, polarisation-tracking free de-multiplexing is attained by eliminating other optical carrier with orthogonal polarisation. An OBPF is a simple polarisation de-multiplexing scheme in which the polarisation-orthogonal carrier can be effectively de-multiplexed and the cross-polarisation interference can be nearly eliminated. Compared with traditional PDM-based fibre-FSO convergent systems with sophisticated polarisation-tracking mechanism and elaborate digital signal processing (DSP) approach, it reveals a noteworthy one with the advantage of simplicity. Through 25 km single-mode fibre transport and 500 m FSO link, sufficiently low bit error rate and qualified PAM4 eye diagrams are attained. This proposed polarisation-tracking free PDM-based fibre-FSO convergent system is notable because it not only incorporates the fibre backbone and optical wireless feeder, but it also simplifies the framework since complicated polarisation-tracking mechanism and DSP approach are not involved.

A PDM-based bi-directional fibre-FSO integration with two RSOAs scheme.

A polarization-division-multiplexing (PDM)-based bi-directional fibre-free-space optical (FSO) integration with two reflective semiconductor optical amplifiers (RSOAs) scheme to efficiently wipe off the modulated data for upstream modulation is proposed and successfully demonstrated. For downstream modulation, a high-speed 128 Gb/s vestigial sideband (VSB)-four-level pulse amplitude modulation (PAM4) fibre-FSO integration is feasibly established. The transmission capacity is increased up to four times through PDM operation and VSB-PAM4 modulation. For uplink transmission, a 10 Gb/s non-return-to-zero fibre-FSO integration with two RSOAs scheme to effectually erase the downstream modulated data is practically constructed. The upstream performance exhibits noticeable enhancement by using of two RSOAs scheme to wipe off the modulated data clearly. Such illustrated PDM-based bi-directional 128 Gb/s (downstream)/10 Gb/s (upstream) fibre-FSO integration is shown to be prominent not only due to its enhancement in the convergence of fibre backhaul and optical wireless reach extender but also because of its benefit in bi-directional transmission for affording high transmission capacity with long-reach optical wireless link and improved upstream performance.

A 30 Gb/s PAM4 underwater wireless laser transmission system with optical beam reducer/expander.

We have, so far as we know, proposed and demonstrated the first 30 Gb/s four-level pulse amplitude modulation (PAM4) underwater wireless laser transmission (UWLT) system with an optical beam reducer/expander over 12.5-m piped underwater channel/2.5-m high-turbidity harbour underwater channel. In piped underwater links, the performances of PAM4 UWLT systems get better with beam reduction given a small amount of light absorbed by the piped water. In highly turbid harbour underwater links, the performances of PAM4 UWLT systems get better with beam expansion given a large amount of scattered light received by the optical receiver. The effect of high-turbidity harbour water that induces scattering angle (beam divergence) on beam diameter is analyzed and optimised to enhance the transmission performances. This proposed PAM4 UWLT system, which uses an optical beam reducer/expander, provides a practical choice for high transmission capacity and considerably develops clarity and high-turbidity scenarios. It presents promising features for affording a high-transmission-rate underwater optical wireless transmission and opening an access to accelerate wide applications of UWLT systems.

Climates on incidence of childhood type 1 diabetes mellitus in 72 countries.

We are aimed to systematically assess the worldwide trend in incidence of childhood type 1 diabetes mellitus (CT1DM) from 1965 to 2012 and to discuss whether climate affect incidence of CT1DM. We searched the relevant literatures in detail to judge the effect of different climates on incidence of CT1DM. The climates included Mediterranean, monsoon, oceanic, continental, savanna, and rainforest. According to different climates, we further researched relevant factor such as sunshine durations and latitudes. The overall incidence of CT1DM in 72 countries was 11.43 (95% CI 10.31-12.55) per 100,000 children/yr. The incidence of CT1DM in Oceanic climate [10.56 (8.69-12.42)] is highest compared with other climates; the incidence in 40°-66°34'N/S [14.71 (12.30-17.29)] is higher than other latitude groups; the incidence in sunshine durations with 3-4 hours per day [15.17 (11.14-19.20)] is highest compared with other two groups; the incidence of CT1DM from 2000 to 2012 [19.58 (14.55-24.60)] is higher than other periods; all p < 0.01. Incidence of CT1DM was increasing from 1965 to 2012, but incidence in Oceanic climate is higher than other climates. Furthermore, it is higher in centers with higher latitude and lower sunshine durations. The climates might play a key role in inducing CT1DM.

Serum TNF-α concentrations in type 2 diabetes mellitus patients and diabetic nephropathy patients: A systematic review and meta-analysis.

OBJECTIVES: The aim of this study was to investigate whether the concentrations of serum tumor necrosis factor-α (TNF-α), a pro-inflammatory cytokine, increased in type 2 diabetes mellitus (T2DM) and type 2 diabetic nephropathy (T2DN) patients. METHODS: The four databases (PubMed, CNKI, WanFang and Chinese-Cqvip) were searched from Jan 1, 1999 to October 1, 2016 for all clinical case-control studies about the serum TNF-α concentrations in T2DM and T2DN patients. All relevant data were extracted from published reports. The meta-analysis was performed to compare the changes of serum TNF-α concentrations of T2DN and T2DM patients in Eastern and Western with healthy controls. We further evaluated concentrations of serum TNF-α in T2DN patients with mincroalbuminuria or macroalbuminuria. Random-effects models were adopted to assess the pooling data among various variations. RESULTS: In total of 6 studies (744 patients and 277 healthy controls) were included in this study. Compared with healthy controls (both p<0.01), the groups of different albuminuria levels and ethnicities both showed that the serum TNF-α levels were significantly elevated in T2DN patients as well as in eastern T2DN patients (p=0.001), but not significant changed in western T2DN patients (p=0.081). The results were stable through sensitivity analysis and no significant publications bias existed in this meta-analysis. CONCLUSIONS: Serum TNF-α concentrations are obviously increased in T2DN and T2DM patients, but higher in T2DN patients, suggesting an elevated inflammatory burden in T2DN patients.

Correlation between serum interleukin-6 level and type 1 diabetes mellitus: A systematic review and meta-analysis.

OBJECTIVE: This report aimed to explore the association between the change of circulating interleukin-6 (IL-6) in patients and the development of type 1 diabetes mellitus (T1DM). METHODS: Four databases (PubMed, CNKI, WanFang and Civip) were used to search and list all clinical case-control studies about serum IL-6 level in T1DM patients between Jan 1, 2000 and Aug 31, 2016. RESULTS: A total of 20 case-control studies with 1238 T1DM patients and 742 healthy controls were included in this study. Compared to healthy controls, the serum content of IL-6 in patients with T1DM was significantly greater (overall: SMD, 1.49; 95% CI, 1.04 to 1.93; p<0.001), and notably increased in all subgroup with different age, ethnic and disease duration (all p<0.001). Furthermore, the analysis in subgroup exhibited that serum levels of IL-6 in the age greater than 20-year old (SMD, 1.64; 95% CI, 0.57-2.71; p<0.001), the diseased duration among 0-10years (SMD, 2.43; 95% CI, 1.42-3.44; p<0.001) and the sorted American group (SMD, 1.68; 95% CI, 0.85-2.51; p<0.001) were higher than those in control groups. CONCLUSIONS: Patients with T1DM were found to be linked to elevated level of serum IL-6, which the age, ethnic and disease durations in T1DM patients had no effect on the serum IL-6 levels for promoting diabetes mellitus.

The novel application of artificial neural network on bioelectrical impedance analysis to assess the body composition in elderly.

BACKGROUND: This study aims to improve accuracy of Bioelectrical Impedance Analysis (BIA) prediction equations for estimating fat free mass (FFM) of the elderly by using non-linear Back Propagation Artificial Neural Network (BP-ANN) model and to compare the predictive accuracy with the linear regression model by using energy dual X-ray absorptiometry (DXA) as reference method. METHODS: A total of 88 Taiwanese elderly adults were recruited in this study as subjects. Linear regression equations and BP-ANN prediction equation were developed using impedances and other anthropometrics for predicting the reference FFM measured by DXA (FFMDXA) in 36 male and 26 female Taiwanese elderly adults. The FFM estimated by BIA prediction equations using traditional linear regression model (FFMLR) and BP-ANN model (FFMANN) were compared to the FFMDXA. The measuring results of an additional 26 elderly adults were used to validate than accuracy of the predictive models. RESULTS: The results showed the significant predictors were impedance, gender, age, height and weight in developed FFMLR linear model (LR) for predicting FFM (coefficient of determination, r2 = 0.940; standard error of estimate (SEE) = 2.729 kg; root mean square error (RMSE) = 2.571kg, P < 0.001). The above predictors were set as the variables of the input layer by using five neurons in the BP-ANN model (r2 = 0.987 with a SD = 1.192 kg and relatively lower RMSE = 1.183 kg), which had greater (improved) accuracy for estimating FFM when compared with linear model. The results showed a better agreement existed between FFMANN and FFMDXA than that between FFMLR and FFMDXA. CONCLUSION: When compared the performance of developed prediction equations for estimating reference FFMDXA, the linear model has lower r2 with a larger SD in predictive results than that of BP-ANN model, which indicated ANN model is more suitable for estimating FFM.