Proceeding the categorization of microplastics through deep learning-based image segmentation.

Microplastics (MPs) have been recognized as prominent anthropogenic pollutants that inflict significant harm to marine ecosystems. Various approaches have been proposed to mitigate the risks posed by MPs. Gaining an understanding of the morphology of plastic particles can provide valuable insights into the source and their interaction with marine organisms, which can assist the development of response measures. In this study, we present an automated technique for identifying MPs through segmentation of MPs in microscopic images using a deep convolutional neural network (DCNN) based on a shape classification nomenclature framework. We used MP images from diverse samples to train a Mask Region Convolutional Neural Network (Mask R-CNN) based model for classification. Erosion and dilation operations were added to the model to improve segmentation results. On the testing dataset, the mean F1-score (F1) of segmentation and shape classification was 0.7601 and 0.617, respectively. These results demonstrate the potential of proposed method for the automatic segmentation and shape classification of MPs. Furthermore, by adopting a specific nomenclature, our approach represents a practical step towards the global standardization of MPs categorization criteria. This work also identifies future research directions to improve accuracy and further explore the possibilities of using DCNN for MPs identification.

Significance of the great protection of the Yangtze River: Riverine input contributes primarily to the presence of PAHs and HMs in its estuary and the adjacent sea.

The Yangtze River protection strategies are expected to improve the water quality and ecological function of the Yangtze River Estuary (YRE). The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) and 6 heavy metals (HMs) in the YRE were measured and the riverine fluxes were calculated subsequently. In particular, the concentrations of low molecular weight PAHs (LMW-PAHs), arsenic (As) and mercury (Hg) in seawater decreased over time, while those of other studied pollutants did not change a lot. In sediments, the concentration changes for all the pollutants were insignificant. For the present pollutants, the river input is the dominant source, and the flux decreased after the protection. The contribution of the discharge from wastewater treatment plants (WWTPs) was quantified. Its influence cannot be ignored. The seafood quality remained stable and the risk via diet was insignificant. Long-term monitoring is necessary, and the positive impact of the Protection Strategy is gradually emerging.

Pulsed rise and growth of the Tibetan Plateau to its northern margin since ca. 30 Ma.

The onset of mountain building along margins of the Tibetan Plateau provides a key constraint on the processes by which the high topography in Eurasia formed. Although progressive expansion of thickened crust underpins most models, several studies suggest that the northern extent of the plateau was established early, soon after the collision between India and Eurasia at ca. 50 Ma. This inference relies heavily on the age and provenance of Cenozoic sediments preserved in the Qaidam basin. Here, we present evidence in the northern plateau for a considerably younger inception and evolution of the Qaidam basin, based on magnetostratigraphies combined with detrital apatite fission-track ages that date the basin fills to be from ca. 30 to 4.8 Ma. Detrital zircon-provenance analyses coupled with paleocurrents reveal that two-stage growth of the Qilian Shan in the northeastern margin of the Tibetan Plateau began at ca. 30 and at 10 Ma, respectively. Evidence for ca. 30 and 10 to 15 Ma widespread synchronous deformation throughout the Tibetan Plateau and its margins suggests that these two stages of outward growth may have resulted from the removal of mantle lithosphere beneath different portions of the Tibetan Plateau.

Can Tourism Development Make Cities More Livable? Investigating 40 Cities in China.

The field of rapid urbanization has recently paid more attention to the relationship between tourism development and liveable city construction. Previous studies have mainly focused on the experiences of tourists in tourist cities and seldom paid attention to the perceptions of local residents. Based on survey data of nearly 10,000 permanent residents in 40 key tourist cities in China, this study uses a multilevel model to quantitatively analyse the natural environment characteristics, sociocultural environment characteristics and comprehensive attraction of tourism in different tourist cities to explore their impact on urban liveability satisfaction. Results show that the developed tourist cities do not exactly correspond to the cities with a high liveability evaluation. The objective evaluation of both the natural environment and the sociocultural environment has an important influence on the liveability of cities, but the influence of the natural environment is stronger than that of the sociocultural environment. An intermediary effect exists in the subjective evaluation of the natural environment and environments for liveability perception. Simultaneously, residents' liveability satisfaction varies according to their age, education level, annual household income and other social and economic conditions. These findings provide insights for developing countries to further improve residents' living quality and urban construction under the condition of the rapid development of tourism.

Feasibility of Ultrasound-Guided Peritoneal Perfusion with Ozone in the Treatment of Chronic Pelvic Pain: A Bicenter Retrospective Analysis.

BACKGROUND: Numerous therapies have been developed for the treatment of chronic pelvic pain (CPP). Oxygen-ozone therapy is a new method for the treatment of CPP. OBJECTIVES: This article evaluated the feasibility of ultrasound-guided peritoneal perfusion with ozone in patients with CPP. STUDY DESIGN: This is a bicenter retrospective study. SETTING: The study was conducted at 2 pain centers of a university hospital. METHODS: The medical records of patients with CPP (n = 60) from March 2016 until October 2018 were collected and reviewed. Group A contained 19 patients who were treated with a 1500 mcg dose of ozonated water (10 mcg/mL concentration and 150 mL volume), group B contained 23 patients using the same dose of ozonated water but a 15 mcg/mL concentration and 100 mL volume. Group C included 18 patients using a similar ozone dose but delivered in an oxygen-ozone mixture (15 mcg/mL concentration and 100 mL volume oxygen-ozone mixture). Visual Analog Scale (VAS) scores for pain of the 3 groups were compared at pretreatment, posttreatment, 1, 3, and 6 months posttreatment. The injection pain was evaluated using a 4-point verbal rating scale. Quality of life (QoL), anxiety, and depression were assessed at pretreatment and at 6 months posttreatment. RESULTS: The VAS scores of the 3 groups decreased over time following treatment. Group A showed much higher pain scores compared with groups B and C at 1, 3, and 6 months posttreatment. However, the injection pain for groups B and C was higher than group A, but there was no difference seen between group B and C. At 6 months posttreatment, the QoL for all patients improved compared with pretreatment, whereas the anxiety and depression did not demonstrate differences. LIMITATIONS: The main limitations of this study are the retrospective study design, limited case number, and short follow-up period. CONCLUSIONS: Ultrasound-guided peritoneal perfusion with ozone is a feasible therapy for patients with CPP.

Single spectral imagery and faster R-CNN to identify hazardous and noxious substances spills.

The automatic identification (location, segmentation, and classification) by UAV- based optical imaging of spills of transparent floating Hazardous and Noxious Substances (HNS) benefits the on-site response to spill incidents, but it is also challenging. With a focus on the on-site optical imaging of HNS, this study explores the potential of single spectral imaging for HNS identification using the Faster R-CNN architecture. Images at 365 nm (narrow UV band), blue channel images (visible broadband of ∼400-600 nm), and RGB images of typical HNS (benzene, xylene, and palm oil) in different scenarios were studied with and without Faster R-CNN. Faster R-CNN was applied to locate and classify the HNS spills. The segmentation using Faster R-CNN-based methods and the original masking methods, including Otsu, Max entropy, and the local fuzzy thresholding method (LFTM), were investigated to explore the optimal wavelength and corresponding image processing method for the optical imaging of HNS. We also compared the classification and segmentation results of this study with our previously published studies on multispectral and whole spectral images. The results demonstrated that single spectral UV imaging at 365 nm combined with Faster R-CNN has great potential for the automatic identification of transparent HNS floating on the surface of the water. RGB images and images using Faster R-CNN in the blue channel are capable of HNS segmentation.

On-site visualized classification of transparent hazards and noxious substances on a water surface by multispectral techniques.

This paper investigated the use of spectra and multispectral images for on-site visualized classification of transparent hazards and noxious substances (HNS), such as benzene, xylene, and palm oil, floating on a water surface with the potential use for rapid classification of multiple HNS during a leak accident. Partial least-squares discrimination analysis (PLS-DA) and least-squares support vector machine (LS-SVM) models achieved a classification accuracy of 100% for spectral reflectance (325-900 nm) and multispectral image at nine wavelengths. Wavelength division and selection were applied for spectra and spectral images, respectively, to reduce the difficulty in data collection and to simplify the redundant bands. This was followed by PLS-DA and LS-SVM modeling. The LS-SVM model based on the least wavelengths (365, 410, 450, and 850 nm) of multispectral images was suggested as the most effective method for on-site visualized classification of transparent HNS on a water surface.

Downregulation of Egr-1 Expression Level via GluN2B Underlies the Antidepressant Effects of Ketamine in a Chronic Unpredictable Stress Animal Model of Depression.

Ketamine is a non-competitive antagonist of N-methyl-D-aspartate receptors (NMDARs). Growing evidence suggests that a single dose of ketamine produces a series of rapid and remarkable antidepressant properties. However, the mechanisms remain unclear. In our study, the antidepressant properties of a single dose of ketamine (10 mg/kg, i.p.) in mice exposed to chronic unpredictable stress (CUS) were assessed using the open-field test (OFT) and the forced swimming test (FST). Early growth response 1 (Egr-1) and postsynaptic density protein 95 (PSD-95) mRNA and protein expression levels were examined using qRT-PCR and western blot, respectively. Dendritic spine density in the CA1 region of the hippocampus was detected by Golgi staining. AMPAR currents in hippocampal slices were measured by electrophysiology. Our study showed that CUS induced a significant depression-like behavior accompanied by an upregulation of Egr-1 and downregulations of PSD-95, spine density, and AMPAR currents in the hippocampus, and a single dose of ketamine rapidly restored these changes. Interestingly, a single dose of Ro-25-6981 (an GluN2B antagonist, 10 mg/kg, i.p.) or Egr-1 siRNA, but not NVP AAM077 (an GluN2A antagonist, 10 mg/kg, i.p.), could produce the same antidepressant effects as ketamine. These data demonstrate that ketamine may produce its rapid antidepressant effects by downregulating the expression of Egr-1 via blocking GluN2B in the hippocampus.

Expansion of the Tibetan Plateau during the Neogene.

The appearance of detritus shed from mountain ranges along the northern margin of the Tibetan Plateau heralds the Cenozoic development of high topography. Current estimates of the age of the basal conglomerate in the Qaidam basin place this event in Paleocene-Eocene. Here we present new magnetostratigraphy and mammalian biostratigraphy that refine the onset of basin fill to ∼25.5 Myr and reveal that sediment accumulated continuously until ∼4.8 Myr. Sediment provenance implies a sustained source in the East Kunlun Shan throughout this time period. However, the appearance of detritus from the Qilian Shan at ∼12 Myr suggests emergence of topography north of the Qaidam occurred during the late Miocene. Our results imply that deformation and mountain building significantly post-date Indo-Asian collision and challenge the suggestion that the extent of the plateau has remained constant through time. Rather, our results require expansion of high topography during the past 25 Myr.

Uplift-driven sediment redness decrease at ~16.5 Ma in the Yumen Basin along the northeastern Tibetan Plateau.

Significant climate shifts in the northeastern Tibetan Plateau have taken place during the Cenozoic, but the reasons behind them remain unclear. In order to unravel the mechanisms driving these climate changes, proxy data with accurate age constraint are needed. Here we present magnetostratigraphy, sediment color (redness a*, and lightness L*) and grain-size analysis from an early to middle Miocene (~20-15.3 Ma) sediment sequence preserved in the Yumen Basin on the northeastern Tibetan Plateau. In this basin, remarkable increase in lightness, decreases in redness and in ratio of hematite (Hm) to goethite (Gt) took place at ~16.5 Ma. We suggest that these changes result from shorter duration of weathering, climatic wetting, and cooling associated with rapid uplift of the Qilian Shan at the middle Miocene.

Analgesic Effects and Neuropathology Changes of Electroacupuncture on Curing a Rat Model of Brachial Plexus Neuralgia Induced by Cobra Venom.

BACKGROUND: Electroacupuncture (EA) is widely applied to treat neuropathic pain. Brachial plexus neuralgia (BPN) is a common form of chronic persistent pain. Few studies have evaluated the analgesic effects and mechanism of EA using the novel animal model of BPN. OBJECTIVE: To observe the curative effects of repeated EA on curing BPN induced by administration of cobra venom to the lower trunk of the right brachial plexus. STUDY DESIGN: Controlled animal study. SETTING: Department of Anesthesiology, Pain Medicine & Critical Care Medicine, Aviation General Hospital of China Medical University. METHODS: Sixty-six adult male Sprague-Dawley rats were equally and randomly divided into the following groups: normal control (NC), brachial plexus neuralgia (BPN), BPN with sham EA stimulation, BPN with EA stimulation starting on postoperative day 1 (EA1), and BPN with EA stimulation starting on postoperative day 12 (EA12). The BPN model was established by administration of cobra venom to the lower trunk of the right brachial plexus. On postoperative day 1 or day 12, EA (constant aquare wave, 2 Hz and 100 Hz alternating frequencies, intensities ranging from 1 - 1.5 - 2 mA) was applied to the right "Shousanli" (LI10) and "Quchi" (LI11) acupoints for 30 minutes, once every other day for 12 times in both groups. Mechanical withdrawal thresholds (MWT) were tested with von Frey filaments. Video recordings were conducted to analyze the spontaneous exploratory behaviors. Moreover, the organizational and structural alterations of the right brachial plexus and cervical cord (C8-T1) were examined via light and electron microscopy. RESULTS: Following the production of the BPN model, the MWT of both ipsilateral and contralateral paws demonstrated a profound decrease (P < 0.05). But after EA interventions, the MWT showed a significant increase (P < 0.05). In comparison to the EA12 group, the analgesic effects of the EA1 group were more significant, and similar results were observed in exploratory behaviors. However, grooming behaviors did not demonstrate significant differences. Meanwhile, on day 12 after surgery it was observed under light microscopy that the inflammatory response in the right brachial plexus and cervical cord (C8-T1) were significantly attenuated after EA stimulation. Furthermore, the demyelination of the brachial plexus and cervical cord (C8-T1) were also reversed. LIMITATIONS: Limitations include the fact that there was demyelination of the cervical cord (C8-T1) in the control group because of inappropriate manipulation. CONCLUSION: Repeated EA contributes significant analgesic effects in the treatment of BPN.

Electroconvulsive Therapy Under General Anesthesia With Cisatracurium, Laryngeal Mask Airways, and Bispectral Index.

OBJECTIVES: Electroconvulsive therapy (ECT) has dramatically reduced musculoskeletal complications when carried out with muscle relaxants under general anesthesia. However, seizure quality can be affected by the depth of anesthesia and choice of anesthetic agent. The purpose of this study was to describe a general anesthetic technique for ECT by using laryngeal mask, bispectral index (BIS), and muscle relaxant monitoring. METHODS: Twenty-one patients, between ages 18 and 70 years (American Society of Anesthesiologists physical status I-III), who underwent a total of 89 sessions of ECT were examined in a retrospective study. Anesthesia was induced by use of propofol (1.0 mg/kg) followed by cisatracurium (0.2 mg/kg). The BIS, train-of-four, and end-tidal carbon dioxide were all monitored continuously. A laryngeal mask airway was used to maintain and protect the airway during the procedure. Electroconvulsive therapy stimuli were applied bilaterally when the train-of-four was assessed as being zero and BIS scores were 70. All patients then received 5 µg sufentanil and 2 mg midazolam, while titrated to maintain the BIS value at 40 to 50, before the muscle relaxation exhibited complete recovery. RESULTS: The mean duration of treatment process takes approximately 82.5 minutes. Mean (SD) seizure length was 58.8 (28.3) seconds, with 4.5% incidence of restimulation per treatment. Incidence of awareness was 0%. No patients exhibited delirium, nausea, vomiting, or myalgia in the postseizure phase. CONCLUSIONS: Bispectral index monitoring of the depth of anesthesia may have improved seizure quality, and awareness did not occur.

Rat Model of Trigeminal Neuralgia Using Cobra Venom Mimics the Electron Microscopy, Behavioral, and Anticonvulsant Drug Responses Seen in Patients.

BACKGROUND: A new animal model of trigeminal neuralgia produced by injecting cobra venom into the infraorbital nerve (ION) trunk in rats had been developed. We tested and extended the model by observing the ultrastructural alterations of neurons and ameliorative effect of pregabalin in cobra venom-induced pain behaviors of rats. OBJECTIVES: The goal of this study was to prove the feasibility of the cobra venom-induced model of trigeminal neuralgia and to demonstrate the demyelination change of ION and medulla oblongata is the major pathological change of trigeminal neuralgia. STUDY DESIGN: An experimental study. SETTING: Department of Anesthesiology, Pain Medicine, and Critical Care Medicine, Aviation General Hospital of China Medical University. METHODS: Experiments were carried out on male Sprague-Dawley rats. Video recordings were taken after the cobra venom injection and pregabalin administration. Ultrastructural alterations of ION and medulla oblongata were observed at the electron microscopic level. We also observed alteration in pain behaviors by analysis of video recordings. RESULTS: Compared to the preoperative and sham-operated group rats, experimental group rats exhibited significant changes in exploratory, resting, face-grooming, and head-shake behaviors on 3, 7, 14 days after operation (P < 0.01). The demyelination changes of ION and medulla oblongata were evident after administration of cobra venom to the ION. Compared to the pre-treated (no pregabalin administration) and control group rats, pregabalin group rats showed profound changes in exploratory, resting, face-grooming, and head-shake behaviors throughout the 14 day study period after treatment with drugs (P < 0.01). LIMITATIONS: Ultrastructural alterations of ION and medulla oblongata were not examined after the treatment with pregabalin. CONCLUSIONS: Video recordings of free behaviors and pregabalin application prove the feasibility of the rat model of trigeminal neuralgia. The results of electron micrographs are consistent with a previous study in humans showing that the demyelination change of axons is the major pathological change of trigeminal neuralgia. The central demyelination alterations may explain why the mechanical threshold was found to be decreased on the non-operated side of experimental animals.

Trigeminal neuralgia induced by cobra venom in the rat leads to deficits in abilities of spatial learning and memory.

BACKGROUND: Patients with chronic pain usually suffer from cognitive impairment, with memory deterioration being the most common deficit that affects daily functioning and quality of life. The causes for this impairment are not clear despite intensive clinical studies. Few studies have evaluated impaired learning using animal models of persistent pain. OBJECTIVE: In this study, a new trigeminal neuralgia model induced by cobra venom was adopted to explore effects of chronic pain on spatial learning and memory in rats. STUDY DESIGN: Controlled animal study. SETTING: Department of Anesthesiology, Pain Medicine & Critical Care Medicine, Aviation General Hospital of China Medical University. METHODS: Thirty adult male Sprague-Dawley rats were randomly divided into 2 groups (n = 15): NS control group and cobra venom group, 0.9% sterile saline or cobra venom solution was injected into the sheath of the infraorbital nerve (ION), respectively. The development of trigeminal neuralgia was accessed by changes in free behavioral activity 3 days before the surgery and 3, 7, 12, 20, and 30 days after the surgery to identify whether the model was successful or not. Morris water maze test determined the abilities of spatial learning and memory at the time points before the surgery, and 2 weeks and 5 weeks after the surgery. We also observed the ultrastructure of the ION and medulla oblongata of rats following 8 weeks of chronic trigeminal neuropathic pain. RESULTS: Rats with the cobra venom injection displayed significantly more face grooming and fewer exploratory activities compared to the NS control group or baseline (P < 0.01). Both groups improved their latency to reach the platform with the largest difference on the first day (P < 0.01), but without memory deficits in a probe trial for the second water maze protocol. For the third water maze testing, the rats in the cobra venom group experienced decreased abilities of spatial learning and memory, a longer latency with spatial memory deficits during the probe trial (P < 0.05). At the ultrastructural level, we found changes in the medulla oblongata after cobra venom injection resulting in severe demyelination and loss of axons that might be implicated in the causes of cognitive deficits. LIMITATIONS: Limitations include partial vision loss in the eye on the lesion side of the rats that might be missed and the absence of evaluating the ultrastructural changes in other parts of the brain. CONCLUSIONS: The results of this study suggest that trigeminal neuralgia induced by cobra venom in adult rats can impair spatial learning and memory function over time and results in demonstrable changes in the ultrastructure of the medulla oblongata. This new animal model may be useful for future studies on the effect of chronic pain on learning and cognition.

A New Animal Model of Brachial Plexus Neuralgia Produced by Injection of Cobra Venom into the Lower Trunk in the Rat.

BACKGROUND: To establish a new animal model for the study of neuropathic pain developed by administration of cobra venom to the brachial plexus (BP) lower trunk. METHODS: Fifty-eight adult male Sprague-Dawley rats were randomly divided into 5 groups. Under pentobarbital sodium anesthesia, cobra venom was injected into the lower trunk or sham operation was performed in the animals. On postoperative day 1 and day 12, pregabalin was administered intragastricly at 30 mg/kg in two groups. Mechanical withdrawal thresholds (MWT) were tested with von Frey filaments. Video recordings were used to analyze the spontaneous behaviors. Meanwhile, our model was confirmed by observing ultrastructural alterations of the BP and cervical cord (C8-T1) via electron microscope examination. RESULTS: In comparison to the blank and sham-operated group, cobra venom-treated rats showed a profound decrease in the MWT, exploratory and increase in grooming behaviors (P<0.05). The changes were long-lasting (up to 60 days), in both ipsilateral and contralateral paws. Furthermore, it was observed under microscopic examination that the myelin sheath was demyelinated in the BP and cervical cord (C8-T1) after injection of cobra venom to the lower trunk. Pregabalin group rats showed changes in MWT and spontaneous behaviors after pregabalin treatment at postoperative day 1 (P>0.05), compared with the control and sham-operated groups. In pregabalin test POD12 group, the decreased MWT and the increased grooming behavior were improved at 20 days after operation. However, pregabalin had no effect on exploratory activity. Results indicate that pregabalin effectively attenuates mechanical hyperalgesia in acute period. CONCLUSIONS: The cobra venom model can be used as a model to induce neuropathic pain and to enable study of the mechanism and treatment.

Changes to the biomass and species composition of Ulva sp. on Porphyra aquaculture rafts, along the coastal radial sandbank of the Southern Yellow Sea.

Compositions, changes and biomass of attached Ulva species on Porphyra rafts along the radial sandbank in the Yellow Sea were investigated, and potential contributions to green tides was analyzed. Ulva prolifera, Ulva flexuosa and Ulva linza were all appeared throughout the investigated period. U. prolifera and U. flexuosa dominated attached Ulva population on Porphyra rafts. Attached Ulva species biomass showed obviously spatial and temporal variations. Temperature, Ulva microscopic propagules and human activities were main factors to influence attached Ulva species biomass. The total attached Ulva species biomass was more than 20,000 fresh weight tons in April, and the green tide causative species U. prolifera accounted 51.03% in April 2013 before green tides occurred. The high biomass of attached Ulva species would contribute most to green tides in the Yellow Sea. But how attached Ulva species on Porphyra rafts contributing to green tides in the Yellow Sea should be further studied.

The origin of the Ulva macroalgal blooms in the Yellow Sea in 2013.

Green algal blooms have occurred in the Yellow Sea for seven consecutive years from 2007 to 2013. In this study, satellite image analysis and field shipboard observations indicated that the Ulva blooms in 2013 originated in the Rudong coast. The spatial distribution of Ulva microscopic propagules in the Southern Yellow Sea also supported that the blooms originated in the Rudong coast. In addition, multi-source satellite data were used to evaluate the biomass of green algae on the Pyropia aquaculture rafts. The results showed that approximately 2784 tons of Ulva prolifera were attached to the rafts and possessed the same internal transcribed spacer and 5S rDNA sequence as the dominant species in the 2013 blooms. We conclude that the significant biomass of Ulva species on the Pyropia rafts during the harvesting season in radial tidal sand ridges played an important role in the rapid development of blooms in the Yellow Sea.