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Purpose To evaluate the application value of MR susceptibility weighted imaging (SWI), quantitative susceptibility imaging (QSM), diffusion tensor imaging (DTI) and diffusion kurtosis imaging (DKI) in the combined diagnosis of micro-structural changes in early Parkinson's disease (PD) patients with brain gray matter nuclei and to provide objective basis for clinical diagnosis. Methods Totally 20 early-stage PD patients (8 males and 12 females; aged 66.50 ± 9.65 years) and their disease courses are about 0.5-6 years. The third part of UPDRS scored as (18.4 ± 9.4).And 20 healthy controls (HC) (13 males and 7 females; aged 61.25 ± 6.87 years) were included in this study. All the subjects were informed of the purpose of this study. And the study was approved by the Ethics Committee of Beihua University Hospital, Jinlin, China. In this study, These images were acquired based on a 3T MR scanner (Ingenia; Philips, Best, the Netherlands) and measured the imaging parameters of gray matter nuclei in early Parkinson's disease by SWI, QSM, DTI and DKI techniques. Then the parameters were obtained by Philips post-processing work station, DKE, MEDI and other software.These ROIs including the substantia nigra, red nucleus, head of caudate nucleus, putamen and thalamus were manually drawn on each parameter mapping images by two MRI physicians. Finally, SPSS 21.0 statistical software is used for data analysis. Results Based on SWI, 15 PD patients and 6 healthy volunteers were diagnosed correctly. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic coincidence rate were 75.0%, 30.0%, 51.7%, 54.5% and 52.5% about the diagnosis of Nigrosome-one on imaging. Based on QSM, 19 PD patients and 11 healthy volunteers were diagnosed correctly. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic coincidence rate were 95.0%, 55.0%, 67.9%, 91.7% and 75.0% about the diagnosis of Nigrosome-one on imaging. In HC group, there was no significant difference in any DKI-derived parameters between DKI3b and DKI5b (P > 0.05). Compared with HC group, the MK value increased within both the substantia nigra and thalamus in PD group(P

SUMMARYFasting is known to improve health, but the precisely beneficial effects of specific types of fasting and their underlying mechanisms are not fully understood. We herein report that in humans, occasional short-term intensive fasting (STIF), a traditional fasting format favored by Asians, promotes erythropoiesis and boosts the function of red blood cells (RBCs) in oxygen transportation, ATP generation, antioxidant capacity, and innate immune response. The rejuvenation of erythropoiesis is more pronounced in humans with low RBC counts. Using mouse models and a human erythroid progenitor cell model, we found that occasional STIF rejuvenates erythropoiesis by enhancing megakaryocyte-erythroid progenitor selfrenewal and erythroid-biased differentiation without compromising normal hematopoiesis. Molecularly, STIF relies on an autophagy-dependent but erythropoietin (EPO) upregulation-independent MS4A3-CDK2 module to augment the production of RBCs. Our findings thus suggest that STIF can occasionally be practiced as an efficient noninvasive intervention for better erythropoiesis, particularly for adults with low RBC counts.Graphical abstractIn briefXu et al showed that short-term intensive fasting (STIF), when occasionally practiced, boosts red blood cell function and promotes erythropoiesis by regulating MS4A3-CDK2 module to enhance megakaryocyte-erythroid progenitor selfrenewal and erythroid-biased differentiation.HighlightsOccasional STIF boosts the function of red blood cellsOccasional STIF promotes erythropoiesis, which is more significant in adults with low red blood cell countsOccasional STIF selectively enhances MEP selfrenewal and erythroid-biased differentiation via MS4A3-CDK2 moduleThe erythropoietic MS4A3-CDK2 response to STIF is autophagy-dependent but EPO upregulation-independent.

Ribavirin (RBV) is an antiviral drug used for treating COVID-19 infection. Its release into natural waters would threaten the health of aquatic ecosystem. This study reports an effective approach to degrade RBV by the trace N-oxyl compounds (2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO) and N-Hydroxyphthalimide (NHPI)) enhanced UV activated free chlorine (UV/Chlorine) process. The results indicated that TEMPO and NHPI at low concentrations (0.1 μM and 1 μM, respectively) could strongly enhance RBV degradation in both deionized water with different pHs and practical surface water. The enhancement was verified to be attributed to the transformation of TEMPO and NHPI into their reactive forms (i.e., TEMPO

Chloroquine Phosphate (CP) is an antiviral drug used for treatment of COVID-19. It is released into wastewater and eventually contaminates natural water. This study reports an effective homogeneous catalysis way for CP degradation by the 2,2,6,6-Tetramethylpiperidine-N-oxyl (TEMPO) enhanced persulfate (PDS) activation under UVB-LEDs irradiation at 305 nm. TEMPO at a low concentration (0.1 μM) enhanced CP degradation in UV

Today, minimally invasive surgery is increasingly used in various operations. Compared with traditional surgery, minimally invasive surgery makes patients less painful and recovers faster after surgery. However, the minimally invasive robotic system may damage surgical instruments or patient organs during the operation. The reason for this situation is the narrow visual space and insufficient tactile feedback. In this paper, we applied a real-time convolutional neural network model based on YOLOv4 to detect surgical instruments during surgery. We selected a public dataset for learning CNN. YOLO' s architecture is applied to the model to detect surgical instruments in real time. Related indicators such as recall and precision were calculated to evaluate the performance of the model.

Here, an efficient in vitro fluorescence biosensor for bovine serum albumin (BSA) based on the aggregation and release of CdS quantum dots (QDs) within carboxymethyl cellulose (CMC) was investigated and discussed. The aggregation of CdS QDs within CMC was prepared by electrostatic interaction. The release of CdS QDs was due to strong covalent linking between BSA and CMC, thus leading to the more favorable combination of BSA and CMC in the system with the presence of BSA. The detection of BSA was based on the quenching and recovery of fluorescence intensity in the system, which was caused by the aggregation and release of CdS QDs. An excellent linear relationship (R2 = 0.99286) was obtained between fluorescence intensity and BSA concentration (0.05–2.00 μM) with a detection limit of 10−8 M. In addition, the detection method showed high selectivity towards BSA and good stability. These results suggest that the method can be utilized as an efficient and highly selective reagent for quantification of BSA for in vitro biological science.

Microplastics (MPs) are emerging pollutants that have gained much attention due to their potential harm to aquatic ecosystems and organisms. In particular, MP conjugates are loaded with chemical contaminants (e.g., atrazine pesticide), which may be ingested by organisms and can pose higher risks. However, the combined pollution effects and interaction mechanisms remain poorly understood. In this study, we systematically explored the adsorption behaviors and mechanisms of atrazine (ATZ) on pristine and aged MPs using kinetics, isotherms, and thermodynamic models. The target MPs included polystyrene (PS), polyethylene (PE), and polypropylene (PP) as well as the corresponding aged types. Moreover, the effects of pH, humic acid (HA), ionic strength, and ion species (Cl

Microcystin-LR (MC-LR), a polypeptide toxin generated by cyanobacteria, threatens the safety of drinking water supplies. In this study, fulvic acid (FA) was separated into two molecular weight (MW) ranges to evaluate the effects of FA size on MC-LR degradation in the chlorine/UV process. The rates of MC-LR degradation were significantly reduced in FA-containing water (3.7 × 10−3 s−1 for small MW FA; 4.3 × 10−3 s−1 for large MW FA) as compared with FA free water (4.9 × 10−3 s−1). The contributions of ClO• to MC-LR degradation were dramatically lower in small MW FA water (0.4%) than large MW FA (13.9%) and FA free water (17.4%), suggesting inhibition by lignin-like substances in FA in the transformation of Cl• to ClO• and scavenging ClO•. Monochlorination and hydroxylation occurred in the first step of the MC-LR degradation process. The accumulation of intermediate products in the chlorine/UV process indicated that small MW FA inhibited further degradation of MC-LR. Small MW FA, rather than MC-LR degradation, was the dominant factor in minimizing MC-LR cytotoxicity toward a human intestinal epithelial cell line.

We theoretically demonstrate a novel, to the best of our knowledge, mechanism for dark pulse excitation in normal dispersion microresonators exploiting free carrier dispersion and free carrier absorption effects due to multi-photon absorption. Dark pulses can be generated in the three- and four-photon absorption regimes in the presence or absence of external reverse bias to control the lifetime of free carriers, respectively. Direct generation of dark pulses is proven to be feasible in both regimes with a frequency fixed laser. The dynamics of their temporal and spectral evolution have also been investigated. Our findings establish a reliable path for dark pulse and Kerr microcomb generation in related platforms with simplified controlling and tuning techniques.

Postimplant validation is an indispensable part in the brachytherapy technique. It provides the necessary feedback to ensure the quality of operation. The ability to pick implanted seed relates directly to the accuracy of validation. To address it, an automatic approach is proposed for picking implanted brachytherapy seeds in 3D CT images. In order to pick seed configuration (location and orientation) efficiently, the approach starts with the segmentation of seed from CT images using a thresholding filter which based on gray-level histogram. Through the process of filtering and denoising, the touching seed and single seed are classified. The true novelty of this approach is found in the application of the canny edge detection and improved concave points matching algorithm to separate touching seeds. Through the computation of image moments, the seed configuration can be determined efficiently. Finally, two different experiments are designed to verify the performance of the proposed approach: (1) physical phantom with 60 model seeds, and (2) patient data with 16 cases. Through assessment of validated results by a medical physicist, the proposed method exhibited promising results. Experiment on phantom demonstrates that the error of seed location and orientation is within ( $$0.6\, \pm \, 0.38$$ ) mm and ( $$2.4 \pm 1.2$$ ) $${^{\circ }}$$ , respectively. In addition, the most seed location and orientation error is controlled within 0.8 mm and 3.5 $${^{\circ }}$$ in all cases, respectively. The average process time of seed picking is 8.7 s per 100 seeds. In this paper, an automatic, efficient and robust approach, performed on CT images, is proposed to determine the implanted seed location as well as orientation in a 3D workspace. Through the experiments with phantom and patient data, this approach also successfully exhibits good performance.

An improved electrokinetic (EK) process for the removal of copper and nickel from municipal sludge was investigated using a custom-made experimental setup. Optimal parameters were identified as an HNO 3 electrolyte concentration of 0.200 mol/L in the anode chamber; NaNO 3 electrolyte concentrations of 0.800 mol/L in the heavy-metals and cathode chambers; and a current density of 2.0 mA/cm 2 . Adjustment of the sludge pH to 3.8 before treatment clearly increased the current efficiency (CE) and decreased the specific energy consumption (SEC) of the process. Under the optimal conditions in EK systems equipped with two and three sludge chambers, the removal efficiencies for copper and nickel were 51.5–82.9% and 46.6–75.1%, respectively, after 132 h. The results of a sequential extraction procedure revealed that the binding states of the metals in the sludge were changed from difficult-to-extract to more easily extractable states after the EK process. Energy consumption calculations showed that the CE increased to 137.8% and the SEC decreased to 2.39 kWh/kg of metals removed when three sludge chambers were equipped in the EK system. A mechanistic analysis of the current method demonstrated that it can be regarded as an effective technique for removing metals from municipal sludge.

With the development of intelligent efficient flexible production system, the requirements for AGV system are becoming higher and higher, especially for heavy equipment logistics workshop and safe sustainable non-conflict work of heavy-duty AGV in production workshop, which are all hot research topics at present. Therefore, a new method is proposed to solve the problem of stability and smooth operation with bidirectional lane in this paper. The method is based on the design of square topology, chains of path planning reservations and dynamic task priority of the logistics workshop, which effectively utilizes environmental resource of the workshop to avoid the collision and to solve deadlocks. To accommodate more complicated situations, different types of the collision and deadlocks are tested. Finally, simulations showed the effect of traffic strategy. This method can be used as reference for the establishment of square workshop structure and a large number of AGV traffic systems.

© 2017 Elsevier Ltd Recently, an increasing level of attention has focused on the emerging technology of anaerobic dynamic membrane bioreactors (AnDMBRs), owing to its merits such as low membrane module cost, easy control of membrane fouling, low energy consumption and sludge production, as well as biogas production. As research on AnDMBRs is still in the nascent stage, an introduction of bioreactor configurations, dynamic membrane (DM) module, and DM layer formation and cleaning is firstly presented. The process performance of the AnDMBR for wastewater treatment is then reviewed with regard to pollutant removal, DM filterability, biogas production, and potential advantages over the conventional anaerobic membrane bioreactor (AnMBR). In addition, the important parameters affecting process performance are briefly discussed. Lastly, the challenges encountered and perspectives regarding the future development of the AnDMBR process to promote its practical applications are presented.

© 2017 Elsevier B.V. A powdered activated carbon-dynamic membrane bioreactor (PAC-DMBR) was developed and used to treat domestic wastewater by dosing with 3 g/L PAC. The experimental results were compared with those of a control DMBR to investigate the filtration performance and various properties of the dynamic membrane (DM) layer. One flat-sheet DM module made of nylon mesh (pore size 75 μm) was used for effluent production at a high stable flux (50–100 L/m2 h) under a 10 cm water head by gravity flow, resulting in continuous operation cycles of 60–120 h. During the operation period, the PAC-DMBR showed enhanced removal efficiency of pollutants, higher stable membrane flux (10 L/m2 h more), lower filtration resistance (6.0–8.0 × 1010 m−1), quicker formation of the DM layer (within 5 min), and better DM layer regeneration after air backwashing. The DM layer in the PAC-DMBR showed a more porous and incompressible structure, because less extracellular polymeric substance and a portion of the biological PAC were incorporated into the DM layer formed as verified by the analytical results. Using high-throughput pyrosequencing technology, it was revealed that at the genus level the diversity of bacterial communities increased from 18 to 23 genera, while several genera that were favored in the PAC-assisted environment or were responsible for degrading complex organics were enriched. Moreover, the abundance of phylum Proteobacteria, which served as pioneer surface colonizers, was reduced in the PAC-DMBR. It was concluded that PAC addition could modify various aspects of the activated sludge and the DM layer properties, which affected the filtration behavior of the DM layer in the PAC-DMBR.

© 2016 Elsevier Ltd Three PAC-DMBRs were developed for wastewater treatment under different PAC dosages with biomass concentrations averaged at 2.5, 3.5 and 5.0 g/L. The DMBRs could be continuously operated at 40–100 L/m2 h, while higher fluxes were obtained within the PAC-DMBRs with hydraulic retention times varying in 4–10 h. A dose of 1 g/L PAC brought about obvious improvement in the sludge particle size distribution, settling, flocculating and dewatering properties due to the formation of biological PAC, and the sludge properties were further improved at a higher PAC dose (3 g/L). The addition of PAC notably shortened the DM formation time after air backwashing and enhanced pollutant removal. Moreover, under a long solid retention time (approximately 150 d), the concentrations of both soluble and bound extracellular polymeric substances (EPS) decreased substantially because of the adsorption and biodegradation effects of the biological PAC. No obvious impact on biomass activity was observed with PAC addition.

© 2016 Elsevier B.V.. Cake sludge attached on membrane surfaces was collected and characterized in a full scale membrane bioreactor (MBR) compared with bulk sludge. The morphological, chemical and microbial properties were examined through microscopic observations, particle size distribution (PSD) analysis, chemical analysis, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and energy-diffusive X-ray (EDX) analysis, specific oxygen utilization rate (SOUR) measurements and Biolog assay. The results showed that fiber-like substances might have served as the skeleton of larger size aggregates in cake sludge. Moreover, much more polysaccharides and inorganic elements such as multivalent cations were accumulated in cake sludge than proteins and humics. Cake sludge showed lower microbial activity for aerobic degradation than bulk sludge, but higher metabolic activity for the degradation of refractory substances (aromatic proteins and humics) other than polysaccharides. Based on batch filtration experiments, it was found that cake sludge had much higher cake layer fouling potential but lower membrane pore blocking resistance, probably due to the heterogeneous structure of cake sludge resulting from accumulation and interaction of various inorganic and organic foulants. This investigation could assist in obtaining a better understanding of the fouling behavior and foulants accumulation properties of cake sludge in the full-scale MBRs.

Position control of a 2DOF underactuated planar flexible robot in joint space is investigated. Firstly, the dynamic equations are given based on the assumed mode method. The position control strategies of this underactuated planar flexible manipulator are designed with the switch of the brake at the passive joint. And the corresponding algorithms of the active and passive joints are proposed in stages. A 2DOF underactuated planar robot experimental setup and its control system is developed. Position control of this manipulator is completed experimentally. The simulative and experimental results show that in respective stage the active and passive joints can track the targets perfectly, which verify the effectiveness of the proposed method. Furthermore, the elastic vibration at the end of the flexible link reflects the rightness of the assumed mode dynamic model for the underactuated flexible manipulator.

Pallet shuttle can dramatically extend the shuttle of SRM when store or retrieve unit loads in deep lane racks. The AS/RS with pallet runner can store more unit loads in the same space. This paper describes a framework in which SRM collaborates with pallet runners to store and retrieve loads efficiently. Throughput estimation method is also presented for this novel type of automated warehouse. The method is developed from traditional dual command cycle.

A Web-based remote control system of a mobile manipulator over Internet is studied. Due to the development of Internet technique and speed increase of transmission, the inexpensive convenient communication approach is provided for the remote control system. However, time delay on Internet is considered as a problem which affects the stability of teleoperation system. Therefore, based on the test and analysis of time delays, the change rules and classifications on time delays are developed. The control strategy and compensation scheme according to different time delays are proposed, and three control modes are embedded into the control system. In this paper, a Web site of the teleoperation system for the mobile manipulator through Internet is developed based on J2EE.

The limitation for a web-based teleoperation system involves time delay in communication. Undesirable communication time delay causes system instabilities. Various techniques have been proposed to alleviate such control problems. This paper proposes an approach that develops a telerobotics system with a wireless web server/client application framework, which employs virtual reality technique to minimize the delay effects. A novel virtual tracker was developed, which acquires the real position and orientation of a mobile robot, and drives the virtual reality scene to display on the remote computer and change with the movements of a mobile robot. This requires only the robot position and orientation data, instead of transmission of the huge amount of video stream data from the robot to the client computer. As a result, the time delay effects can be ignored and system stability achieved. The experimental results have demonstrated the solution for teleoperation technology.