Compact mode converter on SOI based on a polygonal subwavelength grating structure.

In this Letter, we design and experimentally demonstrate compact mode converters with a lightning-like and arrow-like polygonal subwavelength grating (SWG) structure on a silicon-on-insulator (SOI) platform, which can convert the TE0 mode to the TE1 and TE2 modes, respectively. The footprints of the proposed TE0-1 and TE0-2 mode converters are only 4.44 × 1.3 and 5.89 × 1.8 µm2, respectively. The experimental results show the mode converters have a low insertion loss (<1 dB) and a broad bandwidth (>50 nm). The measured cross talks of the TE0-1 and TE0-2 mode converters are -7.2 dB and -10.3 dB, respectively. In addition, the proposed mode converters with the SWG structure have the advantage in fabrication, since only a one-step full-etching process is required.

Study of resonant mode coupling in the transverse-mode-conversion based resonator with an anti-symmetric nanobeam Bragg reflector.

The traveling-wave like Fabry-Perot (F-P) resonators based on transverse-mode-conversion have been extensively studied as on-chip filters. However, the incomplete transverse mode conversion will lead to the coupling between two degenerated resonant modes, which brings additional loss and may further induce the resonance splitting. In this paper, we take the transverse-mode-conversion based resonator with anti-symmetric nanobeam Bragg reflector as an example and study the resonant mode coupling in both the direct-coupled and side-coupled resonators. The coupled mode equations are used to model the incomplete transverse mode conversion of Bragg reflector. The resonant mode coupling can be effectively suppressed by carefully designing the phase shifter length and adding the tapered holes. The insertion loss of less than -1 dB can be achieved in the simulation using the two methods. This work is believed to benefit the design of mode-conversion based resonators with low insertion loss and non-splitting line shape.

Microsphere-Based Microsensor for Miniature Motors' Vibration Measurement.

We present a microsphere-based microsensor that can measure the vibrations of the miniature motor shaft (MMS) in a small space. The microsensor is composed of a stretched fiber and a microsphere with a diameter of 5 µm. When a light source is incident on the microsphere surface, the microsphere induces the phenomenon of photonic nanojet (PNJ), which causes light to pass through the front. The PNJ's full width at half maximum is narrow, surpassing the diffraction limit, enables precise focusing on the MMS surface, and enhances the scattered or reflected light emitted from the MMS surface. With two of the proposed microsensors, the axial and radial vibration of the MMS are measured simultaneously. The performance of the microsensor has been calibrated with a standard vibration source, demonstrating measurement errors of less than 1.5%. The microsensor is expected to be used in a confined space for the vibration measurement of miniature motors in industry.

Experimental demonstration of a photonic convolutional accelerator based on a monolithically integrated multi-wavelength distributed feedback laser.

We propose and experimentally demonstrate a simple and energy-efficient photonic convolutional accelerator based on a monolithically integrated multi-wavelength distributed feedback semiconductor laser using the superimposed sampled Bragg grating structure. The photonic convolutional accelerator operates at 44.48 GOPS for one 2 × 2 kernel with a convolutional window vertical sliding stride of 2 and generates 100 images of real-time recognition. Furthermore, a real-time recognition task on the MNIST database of handwritten digits with a prediction accuracy of 84% is achieved. This work provides a compact and low-cost way to realize photonic convolutional neural networks.

On-chip mode converter based on two cascaded Bragg gratings.

We propose an on-chip mode converter via two cascaded Bragg reflection processes. A forward conversion between two guided modes can be achieved with the aid of an additional mode. The proposed structure is theoretically studied and simulated via the rigorous three-dimensional finite-difference time-domain (3D-FDTD) method. The bandwidth and central wavelength of the proposed mode converter can be adjusted according to our theoretical analysis and simulation results. By applying the similar design approaches as fiber Bragg gratings, conversion spectra with different shapes can be obtained. As an example, several mode converters with bandpass and sidelobe-reduced spectra are designed. We also investigate and verify the mode conversion by experiment. Therefore, the proposed method may pave a new path for the mode converters with desired conversion spectra.

On-chip optical narrowband reflector based on anti-symmetric Bragg grating.

We propose an on-chip optical narrowband reflector (NBR) based on two cascaded Bragg gratings (BGs). A π phase shifted anti-symmetric Bragg grating (π-PS-ASBG) and a rear uniform Bragg grating (UBG), are in-line connected. The π-PS-ASBG provides a hybrid mode resonance between the even- and odd TE (TE0 and TE1) modes, while the UBG is used as a rear reflector to reflect the TE0 mode that transmitted from the π-PS-ASBG. Different from traditional UBG, the reflection bandwidth decreases when the coupling coefficient increases. The calculated 3-dB bandwidth is 0.16 nm when the whole grating length is 400 µm. The proposed NBR can be applied in the cases requiring narrow reflection such as narrow linewidth semiconductor lasers.

General Strategy for Enhancing Electrochemiluminescence of Semiconductor Nanocrystals by Hydrogen Peroxide and Potassium Persulfate as Dual Coreactants.

Semiconductor nanocrystals usually suffer from weak electrogenerated chemiluminescence (ECL) emissions compared with conventional organic emitters. In this work, we propose, for the first time, a very convenient but effective way to greatly enhance ECL emission of semiconductor TiO2 nanotubes (NTs) by H2O2 and K2S2O8 as dual coreactants, generating ECL emission ca. 6.3 and 107 times stronger than that of K2S2O8 or H2O2 as an individual coreactant, respectively. Scanning electron microscopy, X-ray diffraction, and electron paramagnetic resonance spectral studies were carried out to investigate the ECL enhancement mechanism. The ECL enhancement of TiO2 NTs by the K2S2O8-H2O2 system was supposed to originate from the coordination of H2O2 to the TiO2 surface and the synergy effect between H2O2 and K2S2O8 in the ECL process. The coordination of H2O2 to the surface of TiO2 could stabilize the electrogenerated coreactant-related radical OH(•) (hydroxyl radical), which could obviously promote the amount of sulfate radical anion (SO4(•-)) near the electrode surface by inducing decomposition of K2S2O8 into SO4(•-) or inhibiting the consumption of SO4(•-) by its reaction with H2O. The holes (h(+)) released from SO4(•-) were injected into the valence band of TiO2, resulting in more TiO2(+), which combined with the electrons coming from the conduction band with an enhanced light emission. Moreover, this enhancement effect was also applicable to ECL of a CdS nanocrystal film on a glass carbon electrode, with ca. 2.74- and 148.3-fold enhanced ECL intensity correspondingly, indicating wide applications in the development of semiconductor nanocrystal-based ECL biosensors.

A general strategy for photoelectrochemical immunoassay using an enzyme label combined with a CdS quantum dot/TiO2 nanoparticle composite electrode.

Photoelectrochemical (PEC) immunoassay has received increasing attention owing to its good analytical performance and attractive potential for future protein assay. This Letter represents a novel and general strategy for elegant PEC immunoassay of the important cardiac marker troponin T (cTnT) at neutral conditions. Specifically, we first developed an efficient CdS quantum dots (QDs)/TiO2 nanoparticles (NPs) photoelectrode, on the basis of which an exquisite ß-galactosidase (ß-Gal) catalytic system was integrated with sandwich immunobinding for probing cTnT. In pH 7.4, ß-Gal could catalyze the conversion of p-aminophenyl galactopyranoside (PAPG) to p-aminophenol (PAP), which could be easily photo-oxidized to p-quinone imine (PQI). Because the resulting photocurrent was directly related with the target concentration, an innovative PEC immunoassay could be realized for cTnT detection. The neutral operating condition of this protocol would greatly contribute to its wide applicability for protein assay. This work provides the first PEC immunoassay toward cardiac marker and, more significantly, opens a different perspective for future PEC immunoassay development through a general sensing protocol.

Functional-structural decoupling in visual network is associated with cognitive decline in patients with type 2 diabetes mellitus: evidence from a multimodal MRI analysis.

Type 2 diabetes mellitus (T2DM) and cognitive dysfunction are highly prevalent disorders worldwide. Although visual network (VN) alteration and functional-structural coupling are potential warning factors for mild cognitive impairment (MCI) in T2DM patients, the relationship between the three in T2DM without MCI is unclear. Thirty T2DM patients without MCI and twenty-nine healthy controls (HC) were prospectively enrolled. Visual components (VC) were estimated by independent component analysis (ICA). Degree centrality (DC), amplitude of low frequency fluctuation (ALFF) and fractional anisotropy (FA) were established to reflect functional and structural characteristics in these VCs respectively. Functional-structural coupling coefficients were further evaluated using combined FA and DC or ALFF. Partial correlations were performed among neuroimaging indicators and neuropsychological scores and clinical variables. Three VCs were selected using group ICA. Deteriorated DC, ALFF and DC-FA coefficients in the VC1 were observed in the T2DM group compared with the HC group, while FA and ALFF-FA coefficients in these three VCs showed no significant differences. In the T2DM group, DC in the VC1 positively correlated with 2 dimensions in the California Verbal Learning Test, including Trial 4 and Total trial 1-5. The impaired DC-FA coefficients in the VC1 markedly affected the Total perseverative responses % of the Wisconsin Card Sorting Test. These findings indicate that DC and DC-FA coefficients in VN may be potential imaging biomarkers revealing early cognitive deficits in T2DM.

Patterned membranes for improving hydrodynamic properties and mitigating membrane fouling in water treatment: A review.

Membrane technologies have been widely applied in water treatment over the past few decades. However, membrane fouling remains a hinderance for the widespread use of membrane processes because it decreases effluent quality and increases operating costs. To mitigate membrane fouling, researchers have been exploring effective anti-fouling strategies. Recently, patterned membranes are gaining attention as a novel non-chemical membrane modification for membrane fouling control. In this paper, we review the research on patterned membranes used in water treatment over the past 20 years. In general, patterned membranes show superior anti-fouling performances, which mainly results from two aspects: hydrodynamic effects and interaction effects. Due to the introduction of diversified topographies onto the membrane surface, patterned membranes yield dramatic improvements on hydrodynamic properties, e.g., shear stress, velocity field and local turbulence, restraining concentration polarization and foulants' deposition on the membrane surface. Besides, the membrane-foulant and foulant-foulant interactions play an important role in the mitigation of membrane fouling. Due to the existence of surface patterns, the hydrodynamic boundary layer is destroyed and the interaction force as well as the contact area between foulants and surface are decreased, which contributes to the fouling suppression. However, there are still some limitations in the research and application of patterned membranes. Future research is suggested to focus on the development of patterned membranes appropriate for different water treatment scenarios, the insights into the interaction forces affected by surface patterns, and the pilot-scale and long-term studies to verify the anti-fouling performances of patterned membranes in practical applications.

Detach GaN-Based Film to Realize a Monolithic Bifunctional Device for Both Lighting and Detection.

Due to the emerging requirements of miniaturization and multifunctionality, monolithic devices with both functions of lighting and detection are essential for next-generation optoelectronic devices. In this work, based on freestanding (In,Ga)N films, we demonstrate a monolithic device with two functions of lighting and self-powered detection successfully. The freestanding (In,Ga)N film is detached from the epitaxial silicon (Si) substrate by a cost-effective and fast method of electrochemical etching. Due to the stress release and the lightening of the quantum-confined Stark effect (QCSE), the wavelength blueshift of electroluminescent (EL) peak is very small (<1 nm) when increasing the injection current, leading to quite stable EL spectra. On the other hand, the proposed monolithic bifunctional device can have a high ultraviolet/visible reject ratio (Q = 821) for self-powered detection, leading to the excellent detection selectivity. The main reason can be attributed to the removal of Si by the lift-off process, which can limit the response to visible light. This work paves an effective way to develop new monolithic multifunctional devices for both detection and display.

Research Progress of Natural Products and Their Derivatives in Marine Antifouling.

With the increasing awareness of environmental protection, it is necessary to develop natural product extracts as antifouling (AF) agents for alternatives to toxic biocides or metal-based AF paints to control biofouling. This paper briefly summarizes the latest developments in the natural product extracts and their derivatives or analogues from marine microorganisms to terrestrial plants as AF agents in the last five years. Moreover, this paper discusses the structures-activity relationship of these AF compounds and expands their AF mechanisms. Inspired by the molecular structure of natural products, some derivatives or analogues of natural product extracts and some novel strategies for improving the AF activity of protective coatings have been proposed as guidance for the development of a new generation of environmentally friendly AF agents.

[The anti-inflammatory effect of electroacupuncture in mice with spinal cord injury and molecular mechanism based on transcriptome sequencing technology].

OBJECTIVE: To observe the effect of electroacupuncture(EA) on neural function and spinal cord pathological morphology in spinal cord injury(SCI) mice and investigate the anti-inflammatory molecular mechanism of EA on SCI mice from the aspects of gene by using bioinformatics. METHODS: Seventy-two female C57BL/6 mice were randomized into sham operation, model and EA groups, with 24 mice in each group. The SCI model was established by clamping the spinal cord with a serrefine after laminectomy at the 1st lumbar vertebra(L1). EA(1.5 Hz/7.5 Hz, 1.0 mA) was applied to bilateral "Jiaji"(EX-B2) and "Zusanli"(ST36) for 10 min, once a day for 14 consecutive days. Basso Mouse Scale(BMS) score was used to assess the hindlimb locomotor function of mice. Histopathological changes of the injured area of the spinal cord were determined by HE staining. The spinal cord RNA was sequenced by using RNA-Seq technology. The bioinformatic analysis was then performed to detect the diffe-rential genes between groups, and the function classification and the involved pathways were enriched. The mRNA and protein expressions of differential genes were detected and verified by using qRT-PCR and Western blot. RESULTS: Compared with the sham operation group, BMS score of the model group was significantly decreased(P<0.05), while that of EA group was increased relevant to the model group (P<0.05). HE staining showed loose and disordered structure and arrangement, cavitation, more inflammatory infiltration, nucleus pycnosis, and neuronal necrosis in the model group, which was alleviated in the EA group. Compared with the sham operation group, 565 differential genes were detected in the model group, including 545 up-regulated and 20 down-regulated, while 41 were detected between the EA and the model group, including 2 up-regulated and 39 down-regulated in the EA group. Fifteen genes that were all up-regulated after modeling and down-regulated after EA intervention were detected by using Venn plot, which are Retn, Adipoq, Myh1, Actn2, Pck1, Klhl41, Fabp4, Hspb7, Myot, Ankrd2, Hrc, Cox6a2, Obscn, Col2a1, Mybpc1, and 3 inflammation-related genes(Fabp4, Adipoq and Pck1) were finally acquired. The 15 differential genes were annotated into main biological processes, cell composition and molecular function in the GO function classification analysis. The 15 differential genes were then enriched into different KEGG pathways, including the peroxisome proliferatorsactivated receptor (PPAR) signaling pathway, Adipocytokine signaling pathway. The mRNA and protein expressions of Fabp4, Adipoq and Pck1 in spinal cord detected by qRT-PCR and Western blot were significantly increased in the model group (P<0.001, P<0.01), while these were significantly decreased in the EA group relevant to the model group(P<0.001, P<0.01, P<0.05). CONCLUSION: EA can promote the repair of nerve function and improve inflammatory infiltration in SCI mice. The mechanism may be closely related to the down-regulation of inflammatory factors Fabp4, Adipoq and Pck1 expression, and the regulation of PPAR and Adipocytokine signaling pathways.

Abnormalities of cerebral blood flow and the regional brain function in Parkinson's disease: a systematic review and multimodal neuroimaging meta-analysis.

Background: Parkinson's disease (PD) is a neurodegenerative disease with high incidence rate. Resting state functional magnetic resonance imaging (rs-fMRI), as a widely used method for studying neurodegenerative diseases, has not yet been combined with two important indicators, amplitude low-frequency fluctuation (ALFF) and cerebral blood flow (CBF), for standardized analysis of PD. Methods: In this study, we used seed-based d-mapping and permutation of subject images (SDM-PSI) software to investigate the changes in ALFF and CBF of PD patients. After obtaining the regions of PD with changes in ALFF or CBF, we conducted a multimodal analysis to identify brain regions where ALFF and CBF changed together or could not synchronize. Results: The final study included 31 eligible trials with 37 data sets. The main analysis results showed that the ALFF of the left striatum and left anterior thalamic projection decreased in PD patients, while the CBF of the right superior frontal gyrus decreased. However, the results of multimodal analysis suggested that there were no statistically significant brain regions. In addition, the decrease of ALFF in the left striatum and the decrease of CBF in the right superior frontal gyrus was correlated with the decrease in clinical cognitive scores. Conclusion: PD patients had a series of spontaneous brain activity abnormalities, mainly involving brain regions related to the striatum-thalamic-cortex circuit, and related to the clinical manifestations of PD. Among them, the left striatum and right superior frontal gyrus are more closely related to cognition. Systematic review registration: https://www.crd.york.ac.uk/ PROSPERO (CRD42023390914).

Commonalities and distinctions between the type 2 diabetes mellitus and Alzheimer's disease: a systematic review and multimodal neuroimaging meta-analysis.

Background: Alzheimer's disease (AD) and type 2 diabetes mellitus (T2DM) are aging related diseases with high incidence. Because of the correlation of incidence rate and some possible mechanisms of comorbidity, the two diseases have been studied in combination by many researchers, and even some scholars call AD type 3 diabetes. But the relationship between the two is still controversial. Methods: This study used seed-based d mapping software to conduct a meta-analysis of the whole brain resting state functional magnetic resonance imaging (rs-fMRI) study, exploring the differences in amplitude low-frequency fluctuation (ALFF) and cerebral blood flow (CBF) between patients (AD or T2DM) and healthy controls (HCs), and searching for neuroimaging evidence that can explain the relationship between the two diseases. Results: The final study included 22 datasets of ALFF and 22 datasets of CBF. The results of T2DM group showed that ALFF increased in both cerebellum and left inferior temporal gyrus regions, but decreased in left middle occipital gyrus, right inferior occipital gyrus, and left anterior central gyrus regions. In the T2DM group, CBF increased in the right supplementary motor area, while decreased in the middle occipital gyrus and inferior parietal gyrus. The results of the AD group showed that the ALFF increased in the right cerebellum, right hippocampus, and right striatum, while decreased in the precuneus gyrus and right superior temporal gyrus. In the AD group, CBF in the anterior precuneus gyrus and inferior parietal gyrus decreased. Multimodal analysis within a disease showed that ALFF and CBF both decreased in the occipital lobe of the T2DM group and in the precuneus and parietal lobe of the AD group. In addition, there was a common decrease of CBF in the right middle occipital gyrus in both groups. Conclusion: Based on neuroimaging evidence, we believe that T2DM and AD are two diseases with their respective characteristics of central nervous activity and cerebral perfusion. The changes in CBF between the two diseases partially overlap, which is consistent with their respective clinical characteristics and also indicates a close relationship between them. Systematic review registration: PROSPERO [CRD42022370014].

CO2 mitigation measures of power sector and its integrated optimization in China.

Power sector is responsible for about 40% of the total CO2 emissions in the world and plays a leading role in climate change mitigation. In this study, measures that lower CO2 emissions from the supply side, demand side, and power grid are discussed, based on which, an integrated optimization model of CO2 mitigation (IOCM) is proposed. Virtual energy, referring to energy saving capacity in both demand side and the power grid, together with conventional energy in supply side, is unified planning for IOCM. Consequently, the optimal plan of energy distribution, considering both economic benefits and mitigation benefits, is figured out through the application of IOCM. The results indicate that development of demand side management (DSM) and smart grid can make great contributions to CO2 mitigation of power sector in China by reducing the CO2 emissions by 10.02% and 12.59%, respectively, in 2015, and in 2020.

Effect of Pr/Zn on the anti-humidity and acetone-sensing properties of Co3O4 prepared by electrospray.

Co3O4 is a P-type metal-oxide semiconductor which can realize acetone detection at a lower temperature, but the lower working temperature brings the enhanced humidity effect. In order to solve the problem of a Co3O4 gas sensor being easily affected by humidity, an acetone-sensing material of Co3O4 mixed with Pr/Zn was prepared by electrospray in this work. The optimal working temperature of Pr/Zn-Co3O4 is 160 °C, and the detection limit can reach 1 ppm. The fluctuation of the acetone response is about 7.7% in the relative humidity range of 30-90%. Compared with pure Co3O4, the anti-humidity property of this material is obviously enhanced, but the gas-sensing response deteriorates. Compared with Pr-Co3O4, the anti-humidity and acetone sensing properties of Pr/Zn-Co3O4 were both improved. The morphology, composition, crystal state and energy state of the material were analyzed by SEM, EDS, XRD and XPS. The material of Pr/Zn-Co3O4 is a multi-component mixed material composed of PrCoO3, ZnO, Pr6O11 and Co3O4. The improved anti-humidity and acetone sensing properties exhibited by this material are the result of the synergistic effect of ZnO and Pr3+.

[Effect of electroacupuncture on hepatocyte autophagy and oxidative stress in SAMP8 mice by regulating AMPK/mTOR/ULK1 signaling pathway].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on physical strength and expression levels of hepatic AMP-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR), unc-51 like autophagy activating kinase 1 (ULK1) proteins and Atg5, Atg7, Atg13, Beclin1 and ULK1 mRNAs in aging (senescence accelerated mouse/prone 8, SAMP8)mice, so as to exp lore its mechanism underlying delaying aging by activating AMPK/mTOR/ULK1 signaling pathway. METHODS: Twenty-four male SAMP8 mice were randomly divided into model group, rapamycin (autophagy inducer) group, EA group and EA+autophagy inhibitor (EA+inhibitor) group, with 6 mice in each group, and 6 homologous anti-rapid aging male (SAMR1) mice in the same age were used as the control group. Mice of the rapamycin group received intraperitoneal injection of rapamycin solution (2 mg·kg-1·d-1). EA (2 Hz, 1 mA) was applied to bilateral "Taichong"(LR3)and "Shenshu"(BL23) for 15 min each time. Mice of the EA+inhibitor group received intraperitoneal injection of mTOR inhibitor 3-methyladenine (1.5 mg·kg-1·d-1) before the EA intervention each time. The above-mentioned interventions were conducted 6 times a week for 2 consecutive weeks. Physical conditions of mice were assessed by exhaustive swimming tests. Histopathological changes of the liver were observed by H.E. staining. Western blot was used to detect the expression of AMPK, phosphorylated AMPK (p-AMPK), mTOR, phosphorylated mTOR (p-mTOR), ULK1 and phosphorylated ULK1 (p-ULk1) in the liver tissues. The expression levels of Atg5, Atg7, Atg13, Beclin1 and ULK1 (cellular autophagy-related genes) mRNAs in the liver were detected by quantitative real-time PCR. The immunoactivity (IA) of heme oxygenase 1 (HO-1) in the liver was detected by immunohistochemistry, and the activity of superoxide dismutase (SOD) and the content of malondialdehyde (MDA) of the liver were measured by hydroxylamine method for assessing the level of oxidative stress. RESULTS: Compared with the control group, the duration of exhaustive swimming, the expression levels of AMPK, p-AMPK, ULK1 and p-ULK1 proteins, and Atg5, Atg7, Atg13, Beclin1 and ULK1 mRNA, HO-1 IA and SOD activity were considerably down-regulated (P<0.01), while the expression levels of mTOR and p-mTOR and MDA content were significantly up-regulated (P<0.01) in the model group. In comparison with the model group, the duration of the exhausted swimming, the expression levels of AMPK, p-AMPK, ULK1 and p-ULK1 proteins, and Atg5, Atg7, Atg13, Beclin1 and ULK1 mRNAs, HO-1 IA and SOD activity were significantly up-regulated (P<0.01, P<0.05), whereas the expression levels of mTOR and p-mTOR proteins and MDA content were notably down-regulated (P<0.01, P<0.05) in the rapamycin, EA and EA+inhibitor groups. The improvement of the abovementioned indexes of EA+inhibitor group was not as good as rapamycin and EA groups (P<0.01), suggesting an elimination of the therapeutic effects after administration of 3-methyladenine. No significant differences were found between the rapamycin and EA groups in the abovementioned indexes (P>0.05) except p-mTOR and mTOR which were higher in the EA group (P<0.01). H.E. staining showed ambiguous boundary of the liver lobule, disordered arrangement of hepatocytes with a large amount of fat vacuoles at different size and deviation of nucleus, and lysis of some hepatocytes. These situations were relatively milder in the rapamycin and EA groups. CONCLUSION: EA may enhance physical strength and promote cellular autophagy in the liver of aging mice by regulating AMPK/mTOR/ULK1 signaling, thereby inhibiting excessive oxidative stress, and delaying aging process to some extent.

[Influence of electroacupuncture on locomotor function and expression of spinal HMGB1 and TLR4 in mice with spinal cord injury].

OBJECTIVE: To observe the effect of electroacupuncture(EA)on locomotor activity and the expression of high-mobility group box-1(HMGB1) and Toll-like receptor 4(TLR4) in mice with spinal cord injury(SCI), so as to explore its mechanisms underlying improvement of SCI at the acute stage. METHODS: Forty-eight female C57BL/6 mice were equally randomized into 3 groups: sham operation, model and EA. The SCI model was established by clamping the spinal cord with a serrefine after laminectomy at the 1st lumbar vertebra(L1). EA (1.5 Hz/7.5 Hz, 1.0 mA) was applied to "Jiaji"(EXH-B2) for 10 min, once a day for 5 and 14 days, separately. The hindlimb locomotor function was assessed by Basso, Beattie, Bresnahan Locomotor Rating Scale (BBB). Histopathological changes of the injured area of the spinal cord were determined by H.E. staining. The expression levels of spinal HMGB1, TLR4, ionized calcium binding adaptor molecule 1(Iba1) proteins were detected by Western blot, and the Iba1-positive microglial cells and HMGB1 and Iba1 co-labelled microglia were displayed by immunofluorescence staining. RESULTS: After SCI, the BBB scores on day 5 and 14 were obviously decreased (P<0.05), and the expression of HMGB1 on day 14, TLR4 on day 5 and 14, the number of Iba1-positive microglia as well as the co-expressed HMGB1/Iba1-positive microglia on day 5 and 14 were significantly increased in the model group relevant to the sham operation group (P<0.05, P<0.01). In the EA intervention group, SCI-induced reduction of BBB scores on day 5 and 14, and increases of the expression of HMGB1 and Iba1 on day 14, and TLR4 on day 5 and 14, and the number of Iba1-positive cells as well as the co-expressed HMGB1/Iba1-positive microglia on day 14 were reversed relevant to the model group (P<0.05,P<0.01). H.E. staining showed a structural disorder with lots of cavities, severe inflammatory infiltration with a large quantity of inflammatory cells, and a reduction of normal neurons in the injured spinal cord tissue in the model group， which was relatively milder, with lower activation of microglia in the EA group. CONCLUSION: EA can significantly improve locomotor function in SCI mice, which is associated with its effects in suppressing the expression of inflammatory factors such as HMGB1, TLR4, Iba1 and the over-activation of microglia.

Fertiliser recovery from source-separated urine via membrane bioreactor and heat localized solar evaporation.

Urine with its abundant macronutrients (N-P-K) is an ideal resource for the production of fertiliser. However, the odor and pathogens in the raw urine must be removed to meet the public acceptance of urine collection systems and to enable its safe reuse as a fertiliser. In this work, real urine was collected and treated through a pilot-scale gravity-driven membrane bioreactor (GDMBR) to remove the malodorous organics and to nitrify almost 50% of the ammonia into nitrate. The stablised urine was subsequently distilled via low-cost heat localized solar evaporation (HLSE) to produce a non-odorous solid fertiliser. The developed HLSE with a small footprint can attract bulk solution into a vertical insulated space and quickly heat it up to 68 °C within 1 h. The HLSE process had vapour flux at 1.3 kg m-2 h-1 as well as high solar to vapour conversion efficiency at 87%. Based on the EDX mapping and XRD analysis, the generated crystals are mainly NaNO3, NH4Cl, NaCl, NH4H2PO4 and K2HPO4, which are ideal nutrients for vegetation. In this study, the produced urine-derived fertilisers have a better performance on the growth of the leafy basil than the all-purpose commercial fertilisers. Generally, the GDMBR-HLSE is a promising cost-effective and green technology for nutrients recovery from urine.