Development of a synchronous recording and photo-stimulating electrode in multiple brain neurons

The investigation of brain networks and neural circuits involves the crucial aspects of observing and modulating neurophysiological activity. Recently, opto-electrodes have emerged as an efficient tool for electrophysiological recording and optogenetic stimulation, which has greatly facilitated the analysis of neural coding. However, implantation and electrode weight control have posed significant challenges in achieving long-term and multi-regional brain recording and stimulation. To address this issue, we have developed a mold and custom-printed circuit board-based opto-electrode. We report successful opto-electrode placement and high-quality electrophysiological recordings from the default mode network (DMN) of the mouse brain. This novel opto-electrode facilitates synchronous recording and stimulation in multiple brain regions and holds promise for advancing future research on neural circuits and networks

Localization Algorithm Based on Maximum a Posteriori in Wireless Sensor Networks

Many applications and protocols in wireless sensor networks need to know the locations of sensor nodes. A low-cost method to localize sensor nodes is to use received signal strength indication (RSSI) ranging technique together with the least-squares trilateration. However, the average localization error of this method is large due to the large ranging error of RSSI ranging technique. To reduce the average localization error, we propose a localization algorithm based on maximum a posteriori. This algorithm uses the Baye's formula to deduce the probability density of each sensor node's distribution in the target region from RSSI values. Then, each sensor node takes the point with the maximum probability density as its estimated location. Through simulation studies, we show that this algorithm outperforms the least-squares trilateration with respect to the average localization error

Improved Nitrogen Utilization of Faba Bean (<i>Vicia faba</i> L.) Roots and Plant Physiological Characteristics under the Combined Application of Organic and Inorganic Fertilizers

As one of the most important edible legumes worldwide, faba bean can be grown for grain, feed, vegetable, fertilizer, medicine and deep processing. In this study, experiments were designed to determine the combined effect of organic and inorganic fertilizers on the growth and development of faba bean. Dabaipi (a cultivar of Vicia faba L.) was used for the experiments. Five treatments with different ratios of organic nitrogen (N) to total N were applied, including 0% organic fertilizer (0% OF), 25% OF, 50% OF, 75% OF, 100% OF and 0% OF. Chemical urea was used as an inorganic fertilizer. The experimental results showed that 50% OF resulted in the highest faba bean yield, up to 10,337.39 and 13,595.7 kg ha−1 in 2018 and 2019, respectively. Compared with 0% OF, 50% OF increased the yield by 84.47% and 183.17%, respectively. The regression analysis showed that the yield could be maximized when ROT accounted for 51.1%. The 50% OF treatment significantly increased N accumulation in seeds, resulting in higher N partial factor productivity and N harvest index (NHI). N accumulation in green seeds and aboveground plant parts had a significantly positive linear correlation with the yield and NHI, respectively. The 50% OF treatment maintained appropriate N accumulation in vegetative organs and higher N accumulation in reproductive organs and whole plants. Compared to 0% OF, the 50% OF treatment increased the total nodule number per plant (52.5%), fresh nodule weight (55.8%), nitrate reductase activity (70.7%), glutamine synthetase (18.2%) and glutamate synthase activity (42.4%). Therefore, the combined application of 50% OF and 50% inorganic fertilizer can be recommended for faba bean cultivation. This study will provide a theoretical basis for high-yield cultivation of faba bean

Recent Advances in Zinc Hydroxystannate-Based Flame Retardant Polymer Blends

During the combustion of polymeric materials, plenty of heat, smoke, and toxic gases are produced that may cause serious harm to human health. Although the flame retardants such as halogen- and phosphorus-containing compounds can inhibit combustion, they cannot effectively reduce the release of toxic fumes. Zinc hydroxystannate (ZHS, ZnSn(OH)6) is an environmentally friendly flame retardant that has attracted extensive interest because of its high efficiency, safety, and smoke suppression properties. However, using ZHS itself may not contribute to the optimal flame retardant effect, which is commonly combined with other flame retardants to achieve more significant efficiency. Few articles systematically review the recent development of ZHS in the fire safety field. This review aims to deliver an insight towards further direction and advancement of ZHS in flame retardant and smoke suppression for multiple polymer blends. In addition, the fire retarded and smoke suppression mechanism of ZHS will be demonstrated and discussed in depth

Morphology tunable self-assembled Sr2P2O7:Ce3+, Mn2+ phosphor and luminescence properties

Uniform orange-to-red spherical phosphors of Sr2P2O7:Ce3+, Mn2+ have been synthesized by the co-precipitation method and characterized by X-ray powder diffraction, scanning electron microscopy, and photoluminescence spectroscopy. The results indicate that the morphology, size, and photoluminescence properties of Sr2P2O7:Ce3+, Mn2+ phosphors can be effectively controlled by the reaction and the sintering temperatures. Energy transfer from Ce3+ to Mn2+ in Sr2P2O7 phosphor was observed from photoluminescence spectra of Sr2P2O7:Ce3+, Sr2 P2O7:Mn2+, and Sr2P2O7:Ce3+, Mn2+. Moreover, based on a self-assembly process, a possible formation mechanism for the spherical phosphors is proposed. The uniform phosphor spheres obtained in this work exhibit great potential for high-resolution display devices such as light emitting diodes

Characteristics of fatty infiltration and edema of muscle MRI in Duchenne muscular dystrophy patients

Objective To summarize the characteristics of fatty infiltration and edema of muscle MRI in Duchenne muscular dystrophy (DMD) patients. Methods A total of 70 DMD patients underwent Clinical Functional Scale and muscle MRI of the pelvic (gluteus maximus, gluteus medius, gluteus minimus, iliopsoas, piriformis, obturator internus, obturator externus, tensor fasciae latae, pectineus, erector spinae, psoas major muscle, iliacus), thigh (adductor magnus, gracilis, adductor longus, sartorius, rectus femoris, vastus intermedius, vastus medialis, vastus lateralis, biceps femoris, semitendinosus, semimembranosus) and leg (gastrocnemius, soleus, peroneus longus, tibialis posterior, tibialis anterior, flexor hallucis longus, extensor hallucis longus, extensor digitorum longus). T1WI fatty infiltration grade and fat suppression T2WI edema grade were performed to analyze the imaging features of fatty infiltration and edema. Results In 31 muscles, 30 muscles (96.77% ) presented fatty infiltration and 23 (74.19% ) presented edema. The occurrence rate of fatty infiltration was higher than that of edema. A total of 21 muscles including gluteus maximus, were found T1WI fatty infiltration grades greater than 2, and 10 muscles including tibialis posterior, were less than 1. Five muscles including soleus were found fat suppression T2WI edema grade 3. Spearman rank correlation analysis showed positive correlations between T1WI fatty infiltration grade and Clinical Functional Scale in 7 pelvic muscles [gluteus maximus (rs = 0.518, P = 0.016), gluteus medius (rs = 0.528, P = 0.014), gluteus minimus (rs = 0.528, P = 0.014), iliopsoas (rs = 0.695, P = 0.000), piriformis (rs = 0.451, P = 0.040), pectineus (rs = 0.567, P = 0.009), erector spinae (rs = 0.499, P = 0.025)], 7 thigh muscles [adductor magnus (rs = 0.607, P = 0.005), adductor longus (rs = 0.547, P = 0.013), rectus femoris (rs = 0.614, P = 0.004), vastus intermedius (rs = 0.566, P = 0.009), vastus medialis (rs = 0.522, P = 0.018), vastus lateralis (rs = 0.503, P = 0.024), biceps femoris (rs = 0.508, P = 0.022)] and 3 leg muscles [gastrocnemius (rs = 0.715, P = 0.001), peroneus longus (rs = 0.571, P = 0.017), tibialis posterior (rs = 0.514, P = 0.035)]. There was no correlation between T1WI fatty infiltration grade and Clinical Functional Scale in other muscles (P > 0.05, for all). There was no correlation between fat suppression T2WI edema grade and Clinical Functional Scale in all muscles (P > 0.05, for all). Conclusions Fatty infiltration grade can be well used to assess the severity of DMD. The role of muscle edema on assessing clinical severity should be analyzed according to individual muscle characteristics. DOI: 10.3969/j.issn.1672-6731.2018.07.00