III-V-on-silicon photonic devices for optical communication and sensing

In the paper, we review our work on heterogeneous III-V-on-silicon photonic components and circuits for applications in optical communication and sensing. We elaborate on the integration strategy and describe a broad range of devices realized on this platform covering a wavelength range from 850 nm to 3.85 μm

Beyond the 100 Gbaud directly modulated laser for short reach applications

It is very attractive to apply a directly modulated laser (DML)-based intensity-modulation and direct-detection (IM/DD) system in future data centers and 5G fronthaul networks due to the advantages of low cost, low system complexity, and high energy efficiency, which perfectly match the application scenarios of the data centers and 5G fronthaul networks, in which a large number of high-speed optical interconnections are needed. However, as the data traffic in the data centers and 5G fronthaul networks continues to grow exponentially, the future requirements for data rates beyond 100 Gbaud are challenging the existing DML-based IM/DD system, and the main bottleneck is the modulation bandwidth of the DML. In this paper, the data rate demands and technical standards of the data centers and 5G fronthaul networks are reviewed in detail. With the modulation bandwidth requirements, the technical routes and achievements of recent DMLs are reviewed and discussed. In this way, the prospects, challenges, and future development of DMLs in the applications of future data centers and 5G fronthaul networks are comprehensively explored

Neuropathic Pain Causes Pyramidal Neuronal Hyperactivity in the Anterior Cingulate Cortex

The anterior cingulate cortex (ACC) is thought to be important for acute pain perception as well as the development of chronic pain after peripheral nerve injury. Nevertheless, how ACC neurons respond to sensory stimulation under chronic pain states is not well understood. Here, we used an in vivo two-photon imaging technique to monitor the activity of individual neurons in the ACC of awake, head restrained mice. Calcium imaging in the dorsal ACC revealed robust somatic activity in layer 5 (L5) pyramidal neurons in response to peripheral noxious stimuli, and the degree of evoked activity was correlated with the intensity of noxious stimulation. Furthermore, the activation of ACC neurons occurred bilaterally upon noxious stimulation to either contralateral or ipsilateral hind paws. Notably, with nerve injury-induced neuropathic pain in one limb, L5 pyramidal neurons in both sides of the ACC showed enhanced activity in the absence or presence of pain stimuli. These results reveal hyperactivity of L5 pyramidal neurons in the bilateral ACC during the development of neuropathic pain

Optimization and evaluation of fish oil microcapsules

Fish oil microcapsules were prepared using two natural polysaccharides, alginate and chitosan, as the wall materials. A response surface methodology (RSM) was used to optimize the conditions for fish oil encapsulation efficiency (FOEE). The FOEE was investigated with respect to three key-variables in the RSM: ratio of inner oil phase to aqueous phase (X-1, w/w); concentration of the aqueous phase (X-2, wt%); and ratio of the aqueous phase to outer oil phase (X-3, v/v). The optimal, formulation obtained from the RSM model, i.e., 2.7:1 (X-1), 1.6 wt% (X-2), and 11.5:1 (X-3), gave a FOEE of 28%. The model was validated and the fish oil microcapsules prepared under the optimized conditions were characterized in terms of particle size, polydispersity index (PDI), zeta potential, surface morphology, and in vitro release. The average droplet size, PDI, and zeta potential were 915 nm, 0.038, and +5.2 mV, respectively. The fish oil microcapsules were highly uniform microspheres, and had an accumulative release rate of 77.7% in 270 min in a gastrointestinal model, indicating their potential as an alternative carrier for the controlled release of fish oil. In conclusion, formulating optimal microencapsulation conditions by the RSM can be applied to the microencapsulation of various oil-soluble nutrients for food applications. (C) 2016 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved

Fabrication of uniform alginate-agarose microcapsules loading FeSO4 using water-oil-water-oil multiple emulsions system combined with premix membrane emulsification technique

In this study, the uniform alginate-agarose microcapsules entrapping FeSO4 were successfully fabricated by premix membrane emulsification technique combined with ionic crosslinking solidification method. It was the first time to employ four phase emulsions system of W-1/O-1/W-2/O-2 for encapsulating FeSO4 into alginate-agarose microcapsules. We systematically investigated how the preparation parameters including type of oil phase and emulsifier, concentrations of alginate and agarose and volume ratios between oil and water phase influenced the stability of emulsions, the morphology and size distributions of microcapsules and loading efficiency of FeSO4. We found that the stability of emulsion was improved with the increase of viscosity and density of outer oil phase (O-2), the concentration of emulsifier as well as the volume ratio between inner water phase and inner oil phase (W-1/O-1) within a certain range. Besides, loading capacity of Fe2+ in alginate/agarose microcapsules presented an increase tendency with the decrease of the volume ratio between external water phase (W-2) and primary emulsion [W-2/(O-1/W-1) (v/v)], and also decreased with the concentration of W-2

Optimization and evaluation of fish oil microcapsules

Fish oil microcapsules were prepared using two natural polysaccharides, alginate and chitosan, as the wall materials. A response surface methodology (RSM) was used to optimize the conditions for fish oil encapsulation efficiency (FOEE). The FOEE was investigated with respect to three key-variables in the RSM: ratio of inner oil phase to aqueous phase (X-1, w/w); concentration of the aqueous phase (X-2, wt%); and ratio of the aqueous phase to outer oil phase (X-3, v/v). The optimal, formulation obtained from the RSM model, i.e., 2.7:1 (X-1), 1.6 wt% (X-2), and 11.5:1 (X-3), gave a FOEE of 28%. The model was validated and the fish oil microcapsules prepared under the optimized conditions were characterized in terms of particle size, polydispersity index (PDI), zeta potential, surface morphology, and in vitro release. The average droplet size, PDI, and zeta potential were 915 nm, 0.038, and +5.2 mV, respectively. The fish oil microcapsules were highly uniform microspheres, and had an accumulative release rate of 77.7% in 270 min in a gastrointestinal model, indicating their potential as an alternative carrier for the controlled release of fish oil. In conclusion, formulating optimal microencapsulation conditions by the RSM can be applied to the microencapsulation of various oil-soluble nutrients for food applications. (C) 2016 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.</p

Neuropathic Pain Causes Pyramidal Neuronal Hyperactivity in the Anterior Cingulate Cortex

The anterior cingulate cortex (ACC) is thought to be important for acute pain perception as well as the development of chronic pain after peripheral nerve injury. Nevertheless, how ACC neurons respond to sensory stimulation under chronic pain states is not well understood. Here, we used an in vivo two-photon imaging technique to monitor the activity of individual neurons in the ACC of awake, head restrained mice. Calcium imaging in the dorsal ACC revealed robust somatic activity in layer 5 (L5) pyramidal neurons in response to peripheral noxious stimuli, and the degree of evoked activity was correlated with the intensity of noxious stimulation. Furthermore, the activation of ACC neurons occurred bilaterally upon noxious stimulation to either contralateral or ipsilateral hind paws. Notably, with nerve injury-induced neuropathic pain in one limb, L5 pyramidal neurons in both sides of the ACC showed enhanced activity in the absence or presence of pain stimuli. These results reveal hyperactivity of L5 pyramidal neurons in the bilateral ACC during the development of neuropathic pain

The Prmt5-Vasa module is essential for spermatogenesis in Bombyx mori.

In lepidopteran insects, dichotomous spermatogenesis produces eupyrene spermatozoa, which are nucleated, and apyrene spermatozoa, which are anucleated. Both sperm morphs are essential for fertilization, as eupyrene sperm fertilize the egg, and apyrene sperm is necessary for the migration of eupyrene sperm. In Drosophila, Prmt5 acts as a type II arginine methyltransferase that catalyzes the symmetrical dimethylation of arginine residues in the RNA helicase Vasa. Prmt5 is critical for the regulation of spermatogenesis, but Vasa is not. To date, functional genetic studies of spermatogenesis in the lepidopteran model Bombyx mori has been limited. In this study, we engineered mutations in BmPrmt5 and BmVasa through CRISPR/Cas9-based gene editing. Both BmPrmt5 and BmVasa loss-of-function mutants had similar male and female sterility phenotypes. Through immunofluorescence staining analysis, we found that the morphs of sperm from both BmPrmt5 and BmVasa mutants have severe defects, indicating essential roles for both BmPrmt5 and BmVasa in the regulation of spermatogenesis. Mass spectrometry results identified that R35, R54, and R56 of BmVasa were dimethylated in WT while unmethylated in BmPrmt5 mutants. RNA-seq analyses indicate that the defects in spermatogenesis in mutants resulted from reduced expression of the spermatogenesis-related genes, including BmSxl, implying that BmSxl acts downstream of BmPrmt5 and BmVasa to regulate apyrene sperm development. These findings indicate that BmPrmt5 and BmVasa constitute an integral regulatory module essential for spermatogenesis in B. mori