Detection of Helicobacter pylori Infection in Human Gastric Fluid Through Surface-Enhanced Raman Spectroscopy Coupled With Machine Learning Algorithms.

Diagnostic methods for Helicobacter pylori infection include, but are not limited to, urea breath test, serum antibody test, fecal antigen test, and rapid urease test. However, these methods suffer drawbacks such as low accuracy, high false-positive rate, complex operations, invasiveness, etc. Therefore, there is a need to develop simple, rapid, and noninvasive detection methods for H. pylori diagnosis. In this study, we propose a novel technique for accurately detecting H. pylori infection through machine learning analysis of surface-enhanced Raman scattering (SERS) spectra of gastric fluid samples that were noninvasively collected from human stomachs via the string test. One hundred participants were recruited to collect gastric fluid samples noninvasively. Therefore, 12,000 SERS spectra (n = 120 spectra/participant) were generated for building machine learning models evaluated by standard metrics in model performance assessment. According to the results, the Light Gradient Boosting Machine algorithm exhibited the best prediction capacity and time efficiency (accuracy = 99.54% and time = 2.61 seconds). Moreover, the Light Gradient Boosting Machine model was blindly tested on 2,000 SERS spectra collected from 100 participants with unknown H. pylori infection status, achieving a prediction accuracy of 82.15% compared with qPCR results. This novel technique is simple and rapid in diagnosing H. pylori infection, potentially complementing current H. pylori diagnostic methods.

Spatial distribution, environmental risks, and sources of potentially toxic elements in soils from a typical abandoned antimony smelting site.

The rapid development of the smelting industry increases the release of antimony (Sb) into the soil environment, which threatens human health and ecosystems. A total of 87 samples were collected from an abandoned Sb smelting site to evaluate pollution characteristics and environmental risks of the potentially toxic elements (PTEs). The contents of As, Cu, Ni, Pb, Sb, and Zn in the fresh soils determined by P-XRF were 131, 120, 60, 145, 240, and 154 mg/kg, respectively, whilst following drying, grinding, and sieving pretreatments, the corresponding contents increased to 367, 179, 145, 295, 479, and 276 mg/kg, respectively. There was a significant correlation between the data obtained by P-XRF and ICP-OES in the treated samples, which showed the application feasibility of P-XRF. The average contents of Sb and As were 440.6 and 411.6 mg/kg, respectively, which exceeded the control values of the development land in GB 36600-2018. The ecological risk levels of the six PTEs decreased in the following order: As > Sb > Pb > Zn > Ni > Cu. Non-carcinogenic risk revealed that As, Pb, and Sb posed health risks for children, whilst for carcinogenic risk, the risk values for As and Ni were higher than the limit values for both children and adults. Anthropogenic sources accounted for more than 70.0% of As, Pb, and Sb concentrations in soils, indicating a significant influence on PTEs accumulation. The findings provide a basis for quick determination of the contamination characteristics and risk control of PTEs at Sb smelting sites.

Changes in Bacterial and Fungal Microbiomes Associated with Tomatoes of Healthy and Infected by Fusarium oxysporum f. sp. lycopersici.

Fusarium wilt of tomato caused by the pathogen Fusarium oxysporum f. sp. lycopersici (Fol) is one of the most devastating soilborne diseases of tomato. To evaluate whether microbial community composition associated with Fol-infected tomato is different from healthy tomato, we analyzed the tomato-associated microbes in both healthy and Fol-infected tomato plants at both the taxonomic and functional levels; both bacterial and fungal communities have been characterized from bulk soil, rhizosphere, rhizoplane, and endosphere of tomatoes using metabarcoding and metagenomics approaches. The microbial community (bacteria and fungi) composition of healthy tomato was significantly different from that of diseased tomato, despite similar soil physicochemical characteristics. Both fungal and bacterial diversities were significantly higher in the tomato plants that remained healthy than in those that became diseased; microbial diversities were also negatively correlated with the concentration of Fol pathogen. Network analysis revealed the microbial community of healthy tomato formed a larger and more complex network than that of diseased tomato, probably providing a more stable community beneficial to plant health. Our findings also suggested that healthy tomato contained significantly greater microbial consortia, including some well-known biocontrol agents (BCAs), and enriched more functional genes than diseased tomato. The microbial taxa enriched in healthy tomato plants are recognized as potential suppressors of Fol pathogen invasion.

Antimicrobial crinane-type alkaloids from the bulbs of Crinum latifolium.

A phytochemical investigation on the 90% ethanol aqueous extract of the bulbs of Crinum latifolium led to the isolation of three new crinane-type alkaloids, designated as crinumlatines A-C (1-3). The structures of the new compounds were elucidated by spectroscopic analysis (NMR, IR, UV, and MS). The isolated alkaloids were tested in vitro for antimicrobial potentials against 5 pathogenic microorganisms. As a result, compounds 1-3 exhibited some antimicrobial activity against the tested Gram negative bacteria with minimum inhibitory concentration values less than 50 µg/ml.

Determination and comparison of agarwood from different origins by comprehensive two-dimensional gas chromatography-quadrupole time-of-flight mass spectrometry.

Agarwood, a species of resinous heartwood, is a precious medicinal plant and a type of rare natural spice, which is widely used in medicine, cosmetics, religious activities, and other fields. In this study, agarwood samples from eight different regions across four countries were analyzed by comprehensive two-dimensional gas chromatography-quadrupole time-of-flight mass spectrometry. A total of 232 species were identified (the match factors of these compounds were above 750). The main compounds of agarwood are oxygenated sesquiterpenes and chromones. The compositions of India1 and Malaysia2 were significantly different from those of other samples, which might be attributed to the different production processes of agarwood. For further investigation, factor analysis was conducted for six agarwood samples. The results showed that the data classification possessed a regional characteristic; according to the retention time and relative content, characteristic compositions were determined by factor scores. Finally, the differences of characteristic compositions were simply analyzed, and the reasons were speculated.

The Requirement of L-Type Voltage-Dependent Calcium Channel (L-VDCC) in the Rapid-Acting Antidepressant-Like Effects of Scopolamine in Mice.

Background: Previous studies have shown that a low dose of scopolamine produces rapid-acting antidepressant-like actions in rodents. Understanding the mechanisms underlying this effect and the dose-dependent variations of drug responses remains an important task. L-type voltage-dependent calcium channels were found to mediate rapid-acting antidepressant effects of certain medications (e.g., ketamine). Therefore, it is of great interest to determine the involvement of L-type voltage-dependent calcium channels in the action of scopolamine. Methods: Herein, we investigated the mechanisms underlying behavioral responses to various doses of scopolamine in mice to clarify the involvement of L-type voltage-dependent calcium channels in its modes of action. Open field test, novel object recognition test, and forced swimming test were performed on mice administered varied doses of scopolamine (0.025, 0.05, 0.1, 1, and 3 mg/kg, i.p.) alone or combined with L-type voltage-dependent calcium channel blocker verapamil (5 mg/kg, i.p.). Then, the changes in brain-derived neurotrophic factor and neuropeptide VGF (nonacronymic) levels in the hippocampus and prefrontal cortex of these mice were analyzed. Results: Low doses of scopolamine (0.025 and 0.05 mg/kg) produced significant antidepressant-like effects in the forced swimming test, while higher doses (1 and 3 mg/kg) resulted in significant memory deficits and depressive-like behaviors. Moreover, the behavioral changes in responses to various doses may be related to the upregulation (0.025 and 0.05 mg/kg) and downregulation (1 and 3 mg/kg) of brain-derived neurotrophic factor and VGF in the hippocampus and prefrontal cortex in mice. We further found that the rapid-acting antidepressant-like effects and the upregulation on brain-derived neurotrophic factor and VGF produced by a low dose of scopolamine (0.025 mg/kg) were completely blocked by verapamil. Conclusions: These results indicate that L-type voltage-dependent calcium channels are likely involved in the behavioral changes in response to various doses of scopolamine through the regulation of brain-derived neurotrophic factor and VGF levels.

Long-Term Feeding of Elemental Sulfur Alters Microbial Community Structure and Eliminates Mercury Methylation Potential in Sulfate-Reducing Bacteria Abundant Activated Sludge.

This study reported a novel observation that the long-term cultivation of sulfur-reducing bacteria (S0RB) from a sulfate-reducing bacteria (SRB)-abundant seeding sludge with elemental sulfur feeding significantly shaped the microbial community structure and eliminated the mercury methylation potential in the S0RB-enriched sludge. In this study, the enrichments of SRB and S0RB from activated sludge were obtained through long-term cultivations. Subsequently, the batch tests showed that approximately 5000 µg/L Hg (II) was completely removed from the solution by both the SRB-enriched and S0RB-enriched sludge. Extremely low or no MeHg production was observed in the S0RB-enriched sludge (less than the limit of detection, 0.01 µg/L), while 1.49 µg/L MeHg accumulated in the SRB-enriched sludge. Other batch tests using the sludge samples from a replication of the cultivation showed that the methylation capability of the S0RB-enriching sludge gradually diminished to a negligible level over a 6 month cultivation time. However, some mercury-methylation-related bacteria were present in the enrichment of S0RB such as Geobacter. The absence of MeHg in the S0RB-enriched sludge may be attributed to the dissolved organic matter (DOM) instead of the sulfur- and sulfate-reduction pathway or MeHg demethylation when exposed to Hg (II). The cultivated S0RB could be used for mercury-contaminated wastewater treatment without MeHg concern.

Lentivirus-mediated interleukin-1ß (IL-1ß) knock-down in the hippocampus alleviates lipopolysaccharide (LPS)-induced memory deficits and anxiety- and depression-like behaviors in mice.

BACKGROUND: Recent evidence has suggested that peripheral inflammatory responses induced by lipopolysaccharides (LPS) play an important role in neuropsychiatric dysfunction in rodents. Interleukin-1ß (IL-1ß), a pro-inflammatory cytokine, has been proposed to be a key mediator in a variety of behavioral dysfunction induced by LPS in mice. Thus, inhibition of IL-1ß may have a therapeutic benefit in the treatment of neuropsychiatric disorders. However, the precise underlying mechanism of knock-down of IL-1ß in repairing behavioral changes by LPS remains unclear. METHODS: The mice were treated with either IL-1ß shRNA lentivirus or non-silencing shRNA control (NS shRNA) lentivirus by microinjection into the dentate gyrus (DG) regions of the hippocampus. After 7 days of recovery, LPS (1 mg/kg, i.p.) or saline was administered. The behavioral task for memory deficits was conducted in mice by the novel object recognition test (NORT), the anxiety-like behaviors were evaluated by the elevated zero maze (EZM), and the depression-like behaviors were examined by the sucrose preference test (SPT) and the forced swimming test (FST). Furthermore, the levels of malondialdehyde (MDA), superoxide dismutase (SOD), nuclear factor erythroid-derived 2-like 2 (Nrf2), heme oxygenase 1 (HO1), IL-1ß, tumor necrosis factor (TNF-α), neuropeptide VGF (non-acronymic), and brain-derived neurotrophic factor (BDNF) were assayed. RESULTS: Our results demonstrated that IL-1ß knock-down in the hippocampus significantly attenuated the memory deficits and anxiety- and depression-like behaviors induced by LPS in mice. In addition, IL-1ß knock-down ameliorated the oxidative and neuroinflammatory responses and abolished the downregulation of VGF and BDNF induced by LPS. CONCLUSIONS: Collectively, our findings suggest that IL-1ß is necessary for the oxidative and neuroinflammatory responses produced by LPS and offers a novel drug target in the IL-1ß/oxidative/neuroinflammatory/neurotrophic pathway for treating neuropsychiatric disorders that are closely associated with neuroinflammation, oxidative stress, and the downregulation of VGF and BDNF.

Seven-bit reconfigurable optical true time delay line based on silicon integration.

We design, fabricate, and characterize a 7-bit reconfigurable optical true time delay line consisting of Mach-Zehnder interferometer (MZI) switches on the silicon photonics platform. Variable optical attenuators (VOAs) are embedded to suppress the inter-symbol crosstalk caused by the finite extinction ratio of switches. The device can provide a maximum of 1.27 ns delay with a 10 ps resolution over a wide wavelength range. Eye diagram measurement of a 25 Gbps 2(51)-1 pseudo-random bit sequence (PRBS) signal reveals the power penalties only increase 0.17 dB and 0.77 dB after transmission through the shortest (reference) and the longest (1.27 ns delay) paths, respectively.

Continuously tunable reflective-type optical delay lines using microring resonators.

We present a reflective-type optical delay line using waveguide side-coupled 13 microring resonators terminated with a sagnac loop reflector. Light passes through the microring resonator sequence twice, doubling the delay-bandwidth product. Group delay is tuned by p-i-p type microheaters integrated directly in the microring waveguides. Experiment demonstrates that the delay line can potentially buffer 18 bits and the delay can be continuously tuned for 100 ps with a power tuning efficiency of 0.34 ps/mW. Eye diagrams of a 20-Gbps PRBS signal after 10 and 110 ps delays are also examined.

Elimination of methylmercury production potential in excessive sludge in wastewater treatment plants by sulfur addition.

Mercury ions (Hg(II)) in wastewater can accumulate and transform into the highly neurotoxic methylmercury (MeHg) in activated sludge. The release of MeHg can have severe environmental consequences, making the treatment of MeHg-contaminated sludge a pressing concern. In this study, we found that all the collected activated sludge samples, from different wastewater treatment plants in four cities, had the potential for Hg methylation. The Hg-methylating capacity reached a maximum level of 0.70-0.92 µg/g volatile suspended solids after 48 h of exposure to 5 µg/L Hg(II) and showed an average MeHg production rate of 4.8±0.5%. Accordingly, a sludge treatment method involving the addition of elemental sulfur (S0) for a short-term or long-term duration (3 or 180 days, respectively) was proposed. The results demonstrated that this treatment approach effectively mitigated and potentially eliminated MeHg formation by simultaneously reducing Hg bioavailability and Hg-methylating bioactivity. We found that bioavailable Hg(II) ions were converted to a secondary phase similar to insoluble HgS after S0 addition treatment, leading to a decrease in Hg bioavailability in sludge. The enhancement of Hg and extracellular polymeric substances (EPS) complexation via the increasing amount of thiol groups in EPS also reduced the Hg bioavailability after the long-term treatment. Furthermore, the long-term S0 addition significantly reduced the abundance of Hg-methylators with hgcA gene and promoted the growth of Hg-reducers with merA gene, which ensured the complete elimination of MeHg production potential of the excessive activated sludge. Our findings demonstrated that the proposed S0-addition sludge treatment is a promising and safe biotechnology for treating Hg-contaminated sludge. This approach has the potential to contribute significantly to the mitigation of MeHg pollution within environmental contexts.

TaiChiNet: Negative-Positive Cross-Attention Network for Breast Lesion Segmentation in Ultrasound Images.

Breast lesion segmentation in ultrasound images is essential for computer-aided breast-cancer diagnosis. To improve the segmentation performance, most approaches design sophisticated deep-learning models by mining the patterns of foreground lesions and normal backgrounds simultaneously or by unilaterally enhancing foreground lesions via various focal losses. However, the potential of normal backgrounds is underutilized, which could reduce false positives by compacting the feature representation of all normal backgrounds. From a novel viewpoint of bilateral enhancement, we propose a negative-positive cross-attention network to concentrate on normal backgrounds and foreground lesions, respectively. Derived from the complementing opposites of bipolarity in TaiChi, the network is denoted as TaiChiNet, which consists of the negative normal-background and positive foreground-lesion paths. To transmit the information across the two paths, a cross-attention module, a complementary MLP-head, and a complementary loss are built for deep-layer features, shallow-layer features, and mutual-learning supervision, separately. To the best of our knowledge, this is the first work to formulate breast lesion segmentation as a mutual supervision task from the foreground-lesion and normal-background views. Experimental results have demonstrated the effectiveness of TaiChiNet on two breast lesion segmentation datasets with a lightweight architecture. Furthermore, extensive experiments on the thyroid nodule segmentation and retinal optic cup/disc segmentation datasets indicate the application potential of TaiChiNet.

Gestational supplementation of Bifidobacterium, Lactobacillus, and Streptococcus thermophilus attenuates hepatic steatosis in offspring mice through promoting fatty acid ß-oxidation.

Currently, Bifidobacterium, Lactobacillus, and Streptococcus thermophilus (BLS) are widely recognized as the crucially beneficial bacteria in the gut. Many preclinical and clinical studies have shown their protective effects against non-alcoholic fatty liver disease (NAFLD). However, whether gestational BLS supplementation could alleviate NAFLD in the offspring is still unknown. Kunming mice were given a high-fat diet (HFD) for 4 weeks before mating. They received BLS supplementation by gavage during pregnancy. After weaning, offspring mice were fed with a regular diet up to 5 weeks old. Gestational BLS supplementation significantly increased the abundance of Actinobacteriota, Bifidobacterium, and Faecalibaculum in the gut of dams exposed to HFD. In offspring mice exposed to maternal HFD, maternal BLS intake significantly decreased the ratio of Firmicutes to Bacteroidetes as well as the relative abundance of Prevotella and Streptococcus, but increased the relative abundance of Parabacteroides. In offspring mice, maternal BLS supplementation significantly decreased the hepatic triglyceride content and mitigated hepatic steatosis. Furthermore, maternal BLS supplementation increased the glutathione content and reduced malondialdehyde content in the liver. In addition, mRNA and protein expression levels of key rate-limiting enzymes in mitochondrial ß-oxidation (CPT1α, PPARα, and PGC1α) in the livers of offspring mice were significantly increased after gestational BLS supplementation. Thus, gestational BLS supplementation may ameliorate maternal HFD-induced steatosis and oxidative stress in the livers of offspring mice by modulating fatty acid ß-oxidation.

Discovery of novel diaryl substituted isoquinolin-1(2H)-one derivatives as hypoxia-inducible factor-1 signaling inhibitors for the treatment of rheumatoid arthritis.

Since synovial hypoxic microenvironment significantly promotes the pathological progress of rheumatoid arthritis (RA), hypoxia-inducible factor 1 (HIF-1) has been emerged as a promising target for the development of novel therapeutic agents for RA treatment. In this study, we designed and synthesized a series of diaryl substituted isoquinolin-1(2H)-one derivatives as HIF-1 signaling inhibitors using scaffold-hopping strategy. By modifying the substituents on N-atom and 6-position of isoquinolin-1-one, we discovered compound 17q with the most potent activities against HIF-1 (IC50 = 0.55 µM) in a hypoxia-reactive element (HRE) luciferase reporter assay. Further pharmacological studies revealed that 17q concentration-dependently blocked hypoxia-induced HIF-1α protein accumulation, reduced inflammation response, inhibited cellular invasiveness and promoted VHL-dependent HIF-1α degradation in human RA synovial cell line. Moreover, 17q improved the pathological injury of ankle joints, decreased angiogenesis and attenuated inflammation response in the adjuvant-induced arthritis (AIA) rat model, indicating the promising therapeutic potential of compound 17q as an effective HIF-1 inhibitor for RA therapy.

Lipid accumulation product is a valid predictor of hepatic steatosis and nonalcoholic fatty liver disease.

Aims: To evaluate and compare lipid accumulation product (LAP) with alanine aminotransferase (ALT), aspartate aminotransferase (AST), visceral adiposity index (VAI) and triglyceride-glucose index (TyG) as biomarkers for hepatic steatosis and nonalcoholic fatty liver disease (NAFLD). Methods: LAP, ALT, AST, VAI and TyG were measured in 52 biopsy-proven NAFLD patients and 21 control subjects. Additionally, LAP was also measured in 448 ultrasound-proven NAFLD patients and 1009 control subjects. Results: LAP was positively associated with hepatic steatosis and inflammation in biopsy-proven NAFLD. The risk of NAFLD was positively related to LAP and TyG, but LAP showed a better area under the receiver operating characteristic curve for hepatic steatosis and NAFLD. LAP also performed well in recognizing ultrasound-proven NAFLD. Conclusion: LAP is an ideal biomarker of hepatic steatosis and NAFLD.

Identification of chronic non-atrophic gastritis and intestinal metaplasia stages in the Correa's cascade through machine learning analyses of SERS spectral signature of non-invasively-collected human gastric fluid samples.

The progression of gastric cancer involves a complex multi-stage process, with gastroscopy and biopsy being the standard procedures for diagnosing gastric diseases. This study introduces an innovative non-invasive approach to differentiate gastric disease stage using gastric fluid samples through machine-learning-assisted surface-enhanced Raman spectroscopy (SERS). This method effectively identifies different stages of gastric lesions. The XGBoost algorithm demonstrates the highest accuracy of 96.88% and 91.67%, respectively, in distinguishing chronic non-atrophic gastritis from intestinal metaplasia and different subtypes of gastritis (mild, moderate, and severe). Through blinded testing validation, the model can achieve more than 80% accuracy. These findings offer new possibilities for rapid, cost-effective, and minimally invasive diagnosis of gastric diseases.

Deterministic full-scenario analysis for maximum credible earthquake hazards.

Great earthquakes are one of the major threats to modern society due to their great destructive power and unpredictability. The maximum credible earthquake (MCE) for a specific fault, i.e., the largest magnitude earthquake that may occur there, has numerous potential scenarios with different source processes, making the future seismic hazard highly uncertain. We propose a full-scenario analysis method to evaluate the MCE hazards with deterministic broadband simulations of numerous scenarios. The full-scenario analysis is achieved by considering all uncertainties of potential future earthquakes with sufficient scenarios. Here we show an application of this method in the seismic hazard analysis for the Xiluodu dam in China by simulating 22,000,000 MCE scenarios in 0-10 Hz. The proposed method can provide arbitrary intensity measures, ground-motion time series, and spatial ground-motion fields for all hazard levels, which enables more realistic and accurate MCE hazard evaluations, and thus has great application potential in earthquake engineering.

GREnet: Gradually REcurrent Network With Curriculum Learning for 2-D Medical Image Segmentation.

Medical image segmentation is a vital stage in medical image analysis. Numerous deep-learning methods are booming to improve the performance of 2-D medical image segmentation, owing to the fast growth of the convolutional neural network. Generally, the manually defined ground truth is utilized directly to supervise models in the training phase. However, direct supervision of the ground truth often results in ambiguity and distractors as complex challenges appear simultaneously. To alleviate this issue, we propose a gradually recurrent network with curriculum learning, which is supervised by gradual information of the ground truth. The whole model is composed of two independent networks. One is the segmentation network denoted as GREnet, which formulates 2-D medical image segmentation as a temporal task supervised by pixel-level gradual curricula in the training phase. The other is a curriculum-mining network. To a certain degree, the curriculum-mining network provides curricula with an increasing difficulty in the ground truth of the training set by progressively uncovering hard-to-segmentation pixels via a data-driven manner. Given that segmentation is a pixel-level dense-prediction challenge, to the best of our knowledge, this is the first work to function 2-D medical image segmentation as a temporal task with pixel-level curriculum learning. In GREnet, the naive UNet is adopted as the backbone, while ConvLSTM is used to establish the temporal link between gradual curricula. In the curriculum-mining network, UNet ++ supplemented by transformer is designed to deliver curricula through the outputs of the modified UNet ++ at different layers. Experimental results have demonstrated the effectiveness of GREnet on seven datasets, i.e., three lesion segmentation datasets in dermoscopic images, an optic disc and cup segmentation dataset and a blood vessel segmentation dataset in retinal images, a breast lesion segmentation dataset in ultrasound images, and a lung segmentation dataset in computed tomography (CT).

Treatment and remediation of metal-contaminated water and groundwater in mining areas by biological sulfidogenic processes: A review.

Heavy metal pollution in the mining areas leads to serious environmental problems. The biological sulfidogenic process (BSP) mediated by sulfidogenic bacteria has been considered an attractive technology for the treatment and remediation of metal-contaminated water and groundwater. Notwithstanding, BSP driven by different sulfidogenic bacteria could affect the efficiency and cost-effectiveness of the treatment performance in practical applications, such as the microbial intolerance of pH and metal ions, the formation of toxic byproducts, and the consumption of organic electron donors. Sulfur-reducing bacteria (S0RB)-driven BSP has been demonstrated to be a promising alternative to the commonly used sulfate-reducing bacteria (SRB)-driven BSP for treating metal-contaminated wastewater and groundwater, due to the cost-saving in chemical addition, the high efficiency in sulfide production and metal removal efficiency. Although the S0RB-driven BSP has been developed and applied for decades, the present review works mainly focus on the developments in SRB-driven BSP for the treatment and remediation of metal-contaminated wastewater and groundwater. Accordingly, a comprehensive review for metal-contaminated wastewater treatment and groundwater remediation should be provided with the incorporation of the SRB- and S0RB-driven BSP. To identify the bottlenecks and to improve BSP performance, this paper reviews sulfidogenic bacteria presenting in metal-contaminated water and groundwater; highlight the critical factors for the metabolism of sulfidogenic bacteria during BSP; the ecological roles of sulfidogenic bacteria and the mechanisms of metal removal by sulfidogenic bacteria; and the application of the present sulfidogenic systems and their drawbacks. Accordingly, the research knowledge gaps, current process limitations, and future prospects were provided for improving the performance of BSP in the treatment and remediation of metal-contaminated wastewater and groundwater in mining areas.

A comprehensive review on the photocatalytic inactivation of Microcystis aeruginosa: Performance, development, and mechanisms.

Harmful algae blooms (HABs), caused by severe eutrophication and extreme weather, have spread all over the world, posing adverse effects on eco-environment and human health. Microcystis aeruginosa is the dominant harmful cyanobacterial species when HABs occur, and the toxic metabolites produced by it, microcystins, are even fatal to humans. Photocatalytic technology has received wide attention from researchers for its clean and energy-efficient features, while the basic mechanisms and modification methods of photocatalysts have also been widely reported. In recent years, photocatalytic technology has shown great promise in the inhibition of HABs. In this article, we systematically reviewed the progress in photocatalytic performance and algae removal efficiency, discuss the damage mechanisms of photocatalysts for algae removal, including physical damage and various oxidative stresses, and also explore the degradation rates and possible pathways of microcystins. It can be concluded that during the photocatalytic process, the cytoarchitectural integrity of algae cells was damaged, a variety of important protein and enzyme systems were disrupted, and the antioxidant systems collapsed due to the continuous attack of ROS, which adversely affected the normal physiological activities and growth, resulting in the inactivation of algae cells. Moreover, photocatalysts have a degrading effect on microcystins, thus reducing the adverse effects of HAB. Finally, a brief summary of future research priorities regarding the photocatalytic degradation of algae cells is presented. This study helps to enhance the understanding of the destruction mechanism of Microcystis aeruginosa during the photocatalytic process, and provides a reference for the photodegradation of HAB in water bodies.