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Targeting high-speed, low-cost, short-reach intra-datacenter connections, we designed and tested an integrated silicon photonic circuit as a transmitter engine. This engine can be packaged into an optical transceiver module which meets the QSFP-DD Form Factor, together with other electrical/optical components. We first present the design and performance of a high-speed silicon modulator, which had a 3-dB EO bandwidth of &gt, 40 GHz and an ER of &gt, 5 dB. We then incorporated the engine onto a test board and injected a 53.125 Gbaud PAM4 signal. Clear eye patterns were observed at the receiver with TDECQ ~3 dB for all four lanes.

Dense integration of electro-optic (EO) devices in photonic integrated circuits (PICs) is critical to achieve high-capacity, compact and low-cost transceiver modules, and fulfill the increasing bandwidth and/or bandwidth density demands for future computers, servers, data centers, and transport optical network systems. However, the EO crosstalk due to high integration density may degrade the signal transmission performance and eventually limit the possible density of integration. In this content, the study of the EO crosstalk of a PIC and its impact is crucial. In this paper, we systematically investigate and characterize the EO crosstalk between parallel silicon Mach–Zehnder modulators (MZMs). The performance penalty due to crosstalk is measured for different integration densities and data rates. For the MZM pair with a separation of 200 μm, there is a ∼−20 dB RF crosstalk in the frequency range >10 GHz, and up to 1.1 dB power penalty and 2.2 dB optical signal-to-noise ratio penalty are observed for 36-Gb/s on-off-keying signals. Our study can serve as a reference for integration density of large-scale silicon PICs for various applications.

This study aimed to investigate the effects of Cyclocarya paliurus (Batal.) Iljinskaja polysaccharides (CPP) on the glucose-lipid metabolism in T2DM rats. T2DM model was established in 40 Wistar rats which were then randomly divided into model, CPP-1, CPP-2 and CPP-3 groups. Ten normal rats were selected as the control group. The CPP-1, CPP-2 and CPP-3 group were intragastrically administrated with 100, 200 and 400 mg/kg CPP for 4 weeks, respectively. Results showed that, during the treatment, compared with model group, in CPP treatment groups the T2DM symptoms were lightened, and the body weight was improved. After treatment, compared with model group, in CPP-3 group the blood fasting plasma glucose, fasting insulin and glycosylated hemoglobin levels were reduced (P < 0.05), the blood total cholesterol, triglyceride and low-density lipoprotein cholesterol levels were decreased (P < 0.05), the serum C-reactive protein, tumor necrosis factor α and interleukin 6 levels were decreased (P < 0.05), the serum malondialdehyde level was reduced (P < 0.05), and the serum superoxide dismutase and glutathione peroxidase levels were increased (P < 0.05). In conclusion, CPP can alleviate the T2DM in rats, which may be related to its resisting inflammatory response and oxidative stress in body.

Mitochondrial quality control (MQC) and function are determinants for cellular energy metabolism, and their disorders are reported to play an important role in the development of insulin resistance (IR). Salidroside was reported to have beneficial effects on MQC through AMPK pathway; however, it is unknown whether salidroside exerts anti-IR effect with this action. This study sought to investigate the effects of salidroside on IR with an exploration of the mechanisms of its action. Experimental IR models were adopted in high-fat-diet (HFD)-fed mice and palmitate-treated C2C12 myotubes, respectively. Blood levels of glucose and insulin as well as cellular glucose uptake were determined, and mitochondrial function and MQC-associated parameters and reactive oxygen species (ROS) production were analyzed based on treatments with the activator (AICAR), inhibitors (compound C and EX-527) or specific siRNA of Ampk/Sirt1 and mitochondrial ROS scavenger (mito-TEMPO). Protein expression level was determined by Western blot, cellular observation by transmission electron microscope and ROS production by functional analysis kits. Salidroside reduced IR and activated insulin signaling along with the stimulation of AMPK/SIRT1 signaling and downstream regulation of MQC and ROS production. These salidroside effects were comparable to those of AICAR and could be prevented by AMPK/SIRT1 inhibitors or siRNAs, respectively. Salidroside reduces IR and regulates MQC and ROS production by activating AMPK/SIRT1 signaling pathway. Since IR is a critical issue for public health, to explore a potent agent against IR is of high interest. The anti-IR effects of salidroside warrant further experimental and clinical studies.

Insulin resistance (IR) is the primary pathological mechanism underlying type 2 diabetes mellitus (T2DM). Here, the study aimed to ascertain whether and how exercise mediates IR in T2DM. An in vivo mouse model of high-fat diet-induced IR and an in vitro high-glucose-induced IR model were constructed. High long non-coding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) expression was detected in T2MD and was positively correlated with HOMA-IR and resistin levels. Then, short hairpin RNA targeting MALAT1 (sh-MALAT1) or pcDNA-MALAT1 was delivered into human umbilical vein endothelial cells (HUVECs) to knock down or upregulate its expression, respectively. Silencing of MALAT1 resulted in reduced levels of resistin, Ang II, tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), endothelin-1 (ET-1), and p-insulin receptor substrate-1 (p-IRS)/ISR-1, and decreased cell migration, as well as enhanced glucose uptake and levels of nitric oxide (NO) and p-Akt/Akt. In the IR mouse model, exercise was observed to downregulate MALAT1 to reduce resistin, whereby exercise reduced homeostatic model assessment-insulin resistance (HOMA-IR). Besides, exercise also elevated microRNA-382-3p (miR-382-3p) expression in the serum of IR mice. Dual-luciferase reporter and RNA binding protein immunoprecipitation (RIP) assays identified that MALAT1 could bind to miR-382-3p to upregulate resistin. Collectively, the key observations of the study provide evidence that inhibition of MALAT1 elevates miR-382-3p to repress resistin, which consequently underlies the mechanism of exercise protecting against IR, highlighting a direction for T2DM therapy development. Keywords: exercise, type 2 diabetes mellitus, metastasis-associated lung adenocarcinoma transcript 1, microRNA-382-3p, resistin, insulin resistance, vascular endothelial cells

Injection-type silicon electro-optic modulators are widely used in onchip optical interconnections due to its high modulation efficiency. However, as the modulator dimension approaches the wavelength limit, it becomes hard to improve the modulator speed by shrinking the device. A new approach to further scale down the dimension of an intrinsic device in injection-type electro-optic modulators without suffering from subwavelength confinement problem is proposed. The device consists of stacked PN or PiN cells connected by tunneling structures to enable current conduction. The diffusion capacitance is reduced due to the reduction of quasi-neutral region width in each device. In this paper, a detail study is given to the case of a two-cell modulator. A twofold of capacitance reduction and speed improvement are observed. Further speed improvement is expected by splitting the modulator into more cells, and the simulation approach for the tunneling structures in such an optical device is also discussed in details.

The electro-optic crosstalk between two parallel silicon Mach-Zehnder modulators is characterized. Up to 1.6 dB power penalty is observed for 36-Gb/s on-off-keying signals with a ∼-20 dB crosstalk, posing challenge to dense photonic integration.

The spontaneous emission (SE) of Er3+ embedded in a double slot dielectric structure was studied by a quantum-electrodynamical formalism. The study shows that the slot width and the position of Er3+ in slot structure have a significant effect on the SE. The double slot waveguides were fabricated by embedding two low-index Er/Yb silicate material layers into high-index silicon. The radiative efficiency of Er3+ in the double slot waveguides is found to be higher than that of the single slot waveguide, which is consistent with the theory simulation. The 0.67 dB signal enhancement at 1.53 µm in a 4.6-mm-long slot waveguide was observed pumped by 1476 nm laser. These results show the relevance of our model to study the SE processes in multilayer structures and are important for future realization of silicon-compatible active optical devices.