Long-term variations in external phosphorus inputs and riverine phosphorus export in a typical arid and semiarid irrigation watershed.

Excessive phosphorus (P) along with drained water from farmland in the arid and semiarid watersheds when entering into water bodies brings about serious environmental problems in the aquatic ecosystem. It is critical to explore variations in watershed P balance and the relationship between anthropogenic P input and riverine total phosphorus (TP) export in a typical irrigation watersheds. In this study, long-term anthropogenic P variations in Ulansuhai Nur watershed (UNW), a typical irrigation watershed in Yellow River basin, was investigated using a quantitative Net Anthropogenic Phosphorus Input (NAPI) budget model. The results showed that annual NAPI exhibited a significant upward trend with a multi-year average of 2541.6 kg P km-2 yr-1 in the UNW. Hotspots for watershed NAPI were discovered in Linhe and Hangjin Houqi counties. Chemical P fertilizers and livestock breeding were two dominated sources of NAPI. Annual riverine TP export showed a significantly declined trend with a net decrease of 80.6%. The export ratio of watershed NAPI was 0.6%, lower than those reported for other watersheds worldwide. There was a significant positive linear correlation between NAPI and riverine TP export from 2005 to 2009. However, after 2009, riverine TP export exhibited a decreased trend with increasing watershed NAPI, which was attributed to environmental treatment measures. By reconstructing riverine TP export without the impact of pollution treatment measures, annual average reduction amount of riverine TP export from 2009 to 2019 was estimated to be 237.2 ton, 47.2% and 52.8% of which were attributed to the point and nonpoint sources measures. This study not only widens the application scope of NAPI budget method, but also provides useful information of nutrient management and control in the arid and semiarid irrigation watershed.

To what extent do waste management strategies need adaptation to post-COVID-19?

The world has been grappling with the crisis of the COVID-19 pandemic for more than a year. Various sectors have been affected by COVID-19 and its consequences. The waste management system is one of the sectors affected by such unpredictable pandemics. The experience of COVID-19 proved that adaptability to such pandemics and the post-pandemic era had become a necessity in waste management systems and this requires an accurate understanding of the challenges that have been arising. The accurate information and data from most countries severely affected by the pandemic are not still available to identify the key challenges during and post-COVID-19. The documented evidence from literature has been collected, and the attempt has been made to summarize the rising challenges and the lessons learned. This review covers all raised challenges concerning the various aspects of the waste management system from generation to final disposal (i.e., generation, storage, collection, transportation, processing, and burial of waste). The necessities and opportunities are recognized for increasing flexibility and adaptability in waste management systems. The four basic pillars are enumerated to adapt the waste management system to the COVID-19 pandemic and post-COVID-19 conditions. Striving to support and implement a circular economy is one of its basic strategies.

Single-Cell Transcriptomic Analysis Demonstrates the Regulation of Peach Polysaccharides on Circadian Rhythm Disturbance.

SCOPE: Plant polysaccharides are thought to have a prebiotic effect, promoting the growth of probiotics, which may regulate circadian rhythms. This study evaluates the regulation of peach polysaccharides (PPS) on circadian rhythm disturbance through intestinal microbiota by a mouse model. METHODS AND RESULTS: PPS is administered to mice with circadian rhythm disturbance for 4 weeks. The study finds that PPS ameliorated the structural disorder of intestinal microbiota induced by continuous darkness, decreasing the ratio of Firmicutes/Bacteroidetes (F/B), thereby regulating furfural degradation, penicillin and cephalosporin biosynthesis, and antibiotic biosynthesis. Single-cell transcriptomics is used to determine the type of hypothalamus cells and the expression of clock genes in mice, showing that the number of astrocytes and oligoendrocytes cells in the hypothalamus of the transplanted mice is up-regulated, and the expression of neuroprotective genes such as Sox9 and Mobp increased. In addition, clock genes such as Cry2 and Per3 show significant callback. CONCLUSION: This study shows that PPS can ameliorate the imbalance of intestinal microbiota and cell dysfunction caused by circadian rhythm disorder, suggesting that PPS is a feasible strategy for the prevention and treatment of circadian rhythm disorder and related cognitive impairment.

Strategies for circadian rhythm disturbances and related psychiatric disorders: a new cue based on plant polysaccharides and intestinal microbiota.

Circadian rhythm is essential to human physiological homeostasis and health. The oscillation of host circadian rhythm affects the composition and function of intestinal microbiota, meanwhile, the normal operation of host circadian rhythm depends on the diurnal changes of intestinal microbiota. The imbalance of intestinal micro-ecology or the disorder of host circadian rhythm may lead to psychiatric disorders, while the intervention of plant polysaccharides is a possible way to alleviate circadian rhythm disturbance and the related psychiatric diseases. This review discusses the interaction between host circadian rhythm and intestinal microbiota and their effects on psychiatric disorders, and proposes a possible strategy of plant polysaccharides to alleviate circadian rhythm disorders and related psychiatric disorders by regulating intestinal micro-ecology.

The interaction between tea polyphenols and host intestinal microorganisms: an effective way to prevent psychiatric disorders.

Tea polyphenols (TP) are the most bioactive components in tea extracts. It has been reported that TP can regulate the composition and the function of the intestinal flora. Meanwhile, intestinal microorganisms improve the bioavailability of TP, and the corresponding metabolites of TP can regulate intestinal micro-ecology and promote human health more effectively. The dysfunction of the microbiota-gut-brain axis is the main pathological basis of depression, and its abnormality may be the direct cause and potential influencing factor of psychiatric disorders. The interrelationship between TP and intestinal microorganisms is discussed in this review, which will enable us to better evaluate the potential preventive effects of TP on psychiatric disorders by modulating host intestinal microorganisms.

GPR120 promotes radiation resistance in esophageal cancer via regulating AKT and apoptosis pathway.

The aim of the study is to investigate the role of GPR120 on the biological behavior of esophageal cancer cells in the setting of radiation and explore the mechanism. GPR120 knockdown was fulfilled by siRNA-mediated effects in two esophageal cancer cell lines Eca109 and EC9706. Colony formation, survival fraction calculation, viable cell evaluation by cell counting kit-8 assay and cell apoptosis analysis by phycoerythrin annexin V and 7-amino-actinomycin (7-AAD) staining and the flow cytometry examination was evaluated in Eca109 and EC9706 under the treatment of different radiation dosage. The mechanisms were explored by the evaluation of the Akt pathway and apoptosis protein level. Significantly decreased GPR120 mRNA and protein after GPR120 siRNA treatment compared to control siRNA treatment. Significantly decreased colony formation was found in GPR120 siRNA-treated Eca109 and EC9706 cells compared to control siRNA-treated cells at the radiation dosage of 2, 4, 6 and 8 Gy. Moreover, decreased survival fraction number with increased sensitive enhancing ratio was also found in GPR120 siRNA-treated Eca109 and EC9706 cells compared to control siRNA-treated cells. Decreased cell viability and increased cell apoptosis in GPR120 siRNA-treated esophageal cancer cells. GPR120 siRNA decreased the Akt phosphorylation and anti-apoptotic Bcl-2 expression level, but increased pro-apoptotic Bim expression level in esophageal cancer cell lines. GPR120 regulated the biological behavior of the esophageal cancer cells via affecting Akt pathway and apoptosis molecules. Moreover, GPR120 siRNA combined radiation treatment could be a therapeutic choice for esophageal cancer.

Joint analytical hierarchy and metaheuristic optimization as a framework to mitigate fertilizer-based pollution.

The emission of nitrogenous pollution from agricultural lands in form of ammonia volatilization, leaching, runoff, N2O emissions, etc. is still a serious challenge to which agricultural sector faces. In this context, a vast number of decision support systems have been developed and tested to find the best nitrogen application rate. These models are highly dependent on crop simulation models, mathematical and regression models, evolutionary algorithms and artificial intelligent, GIS-based models, etc., while in most cases have ignored to be interfered with regional and national regulations established by experts in the field. In this study, a new framework combining analytical hierarchy (AHP)/modified AHP methods (MAHP) plus metaheuristic optimization techniques has been suggested to find the best nitrogen application rate considering regional capacities and requirements. To reach the objectives of the present study a three yield field experiment was conducted upon which crop yield, nitrogen use efficiency, nitrogen uptake, soil nitrate, ammonia volatilization, N2O emissions, and N leaching were monitored or measured. Using the results from the field experiments and a survey from local experts, the models were developed. AHP-assisted optimization model could cause some biases in the final results due to its intrinsic nature which avoids direct pairwise comparison among indicators (so called sub-criteria) under two different main-criteria. On the contrary, MAHP-assisted model could well reflect the concerns of experts and notably decrease hotspot pollution. Such decision support system can satisfy both farmers and environmentalists' need because of the created high profit and low environmental pollution, while saving resources and ensuring a sustainable production system.

The modulatory effect of plant polysaccharides on gut flora and the implication for neurodegenerative diseases from the perspective of the microbiota-gut-brain axis.

The microbiota-gut-brain axis includes a two-way communication pattern between the microorganisms that live in our gut and our brain function and behavior. Intestinal flora disorders not only induce related metabolic diseases, but also have an important relationship with neurodegenerative diseases. The present studies have shown that natural polysaccharides are important for maintaining the steady status of intestinal flora. This review aims to summarize the two-way relationship between the gut microbiota and the brain, and the modulatory effect of plant polysaccharides on gut flora, which provides new ideas for the prevention and treatment of the neurodegenerative diseases.

Automatic coronary calcium scoring using noncontrast and contrast CT images.

PURPOSE: Calcium scoring is widely used to assess the risk of coronary heart disease (CHD). Accurate coronary artery calcification detection in noncontrast CT image is a prerequisite step for coronary calcium scoring. Currently, calcified lesions in the coronary arteries are manually identified by radiologists in clinical practice. Thus, in this paper, a fully automatic calcium scoring method was developed to alleviate the work load of the radiologists or cardiologists. METHODS: The challenge of automatic coronary calcification detection is to discriminate the calcification in the coronary arteries from the calcification in the other tissues. Since the anatomy of coronary arteries is difficult to be observed in the noncontrast CT images, the contrast CT image of the same patient is used to extract the regions of the aorta, heart, and coronary arteries. Then, a patient-specific region-of-interest (ROI) is generated in the noncontrast CT image according to the segmentation results in the contrast CT image. This patient-specific ROI focuses on the regions in the neighborhood of coronary arteries for calcification detection, which can eliminate the calcifications in the surrounding tissues. A support vector machine classifier is applied finally to refine the results by removing possible image noise. Furthermore, the calcified lesions in the noncontrast images belonging to the different main coronary arteries are identified automatically using the labeling results of the extracted coronary arteries. RESULTS: Forty datasets from four different CT machine vendors were used to evaluate their algorithm, which were provided by the MICCAI 2014 Coronary Calcium Scoring (orCaScore) Challenge. The sensitivity and positive predictive value for the volume of detected calcifications are 0.989 and 0.948. Only one patient out of 40 patients had been assigned to the wrong risk category defined according to Agatston scores (0, 1-100, 101-300, >300) by comparing with the ground truth. CONCLUSIONS: The calcified lesions in the noncontrast CT images can be detected automatically by using the segmentation results of the aorta, heart, and coronary arteries obtained in the contrast CT images with a very high accuracy.

Apoptosis is an obstacle to the differentiation of adipose-derived stromal cells into astrocytes.

Previous studies have demonstrated that nerve cells differentiated from adipose-derived stromal cells after chemical induction have reduced viability; however, the underlying mechanisms remained unclear. In this study, we induced the differentiation of adult adipose-derived stromal cells into astrocytes using chemical induction. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and flow cytometry showed that, with increasing induction time, the apoptotic rate gradually increased, and the number of living cells gradually decreased. Immunohistochemical staining demonstrated that the number of glial fibrillary acidic protein-, caspase-3- and caspase-9-positive cells gradually increased with increasing induction time. Transmission electron microscopy revealed typical signs of apoptosis after differentiation. Taken together, our results indicate that caspase-dependent apoptosis is an obstacle to the differentiation of adipose-derived stromal cells into astrocytes. Inhibiting apoptosis may be an important strategy for increasing the efficiency of induction.

The effect of autophagy in the process of adipose-derived stromal cells differentiation into astrocytes.

Autophagy plays different roles in the growth and development process of different cells. The role of autophagy in the differentiation process of adult adipose-derived stromal cells (ADSCs) into astrocytes is unclear. We researched the role of autophagy in the induction process by adding autophagy agonist rapamycin, which was not added in the control group. Immunocytochemistry showed that the expression of glial fibrillary acidic protein (GFAP) was increased gradually with the extending reaction time and had reached the peak on the 14th day. Typical autophagy ultrastructure, including autophagic bodies and self-macrophage lysosomal, was shown under transmission electron microscopy (TEM) when cells were induced for 14 days. By methyl thiazolyl tetrazolium (MTT) assay, we found that the number of living cells was reduced gradually, and early apoptosis rate was increased by flow cytometry. We observed that the differentiation ratio, the number of living cells, and the positive expression rates of GFAP in the rapamycin group were higher than those in the control group when ADSCs were induced for 48 h and 7 days (P < 0.01); however, the rates of early apoptosis were lower than those in the control group. The positive rate of microtubule-associated protein light chain 3 (LC3) in the rapamycin group had been up to 88.87% on the 7th day (P < 0.01), but not obvious with extending time. After 14 days of induction, the optical density (OD) value of surviving cells was declined, and early apoptosis rate was increased gradually. The results showed that adding autophagy agonist to the inducers may enhance intensity of autophagy, shorten the induction time, and improve the efficiency of differentiation.

Autophagy activator promotes neuronal differentiation of adult adipose-derived stromal cells.

Preliminary research from our group found altered autophagy intensity during adipose-derived stromal cell differentiation into neuronal-like cells, and that this change was associated with morphological changes in differentiated cells. This study aimed to verify the role of rapamycin, an autophagy activator, in the process of adipose-derived stromal cell differentiation into neuronal-like cells. Immunohistochemical staining showed that expression of neuron-specific enolase and neurofilament-200 were gradually upregulated in adipose-derived stromal cells after 5 mM ß-mercaptoethanol induction, and the differentiation rate gradually increased with induction time. Using transmission electron microscopy, induced cells were shown to exhibit cytoplasmic autophagosomes, with bilayer membranes, and autolysosomes. After rapamycin (200 µg/L) induction for 1 hour, adipose-derived stromal cells began to extend long processes, similar to the morphology of neuronal-like cells, while untreated cells did not exhibit similar morphologies until 3 hours after induction. Moreover, the differentiation rate was significantly increased after rapamycin treatment. Compared with untreated cells, expression of LC3, an autophagy protein, was also significantly upregulated. Positive LC3 expression tended to concentrate at cell nuclei with increasing induction times. Our experimental findings indicate that autophagy can significantly increase the speed of adipose-derived stromal cell differentiation into neuronal-like cells.

Autophagy and apoptosis during adult adipose-derived stromal cells differentiation into neuron-like cells in vitro.

ß-mercaptoethanol can induce adult adipose-derived stromal cells to rapidly and efficiently differentiate into typical neuron-like cells in vitro. Immunohistochemistry showed that neuron specific enolase and neurofilament-200 expression gradually increased with the extension of induction time, and peaked at 5 hours. By contrast, glial fibrillary acidic protein was negatively expressed at all time points. Induced cells possessed a typical Nissl body, apoptosis showing condensed chromatin in the nucleus, autophagosomes with a bilayered membrane and autolysosomes in the cytoplasm at 5 hours. TUNEL assay and immunohistochemistry and immunofluorescence demonstrated that apoptosis and caspase-3 expression increased and peaked at 8 hours. Immunohistochemistry and immunofluorescence showed that microtubuleassociated protein light chain 3 gradually increased with induction and reached a peak at 5 hours. These results indicate that autophagy played an important role in protecting cells during adult adipose-derived stromal cells differentiation into neuron-like cells in vitro.

Covalently attached monolayers on crystalline hydrogen-terminated silicon: extremely mild attachment by visible light.

A very mild method was developed for the attachment of high-quality organic monolayers on crystalline silicon surfaces. By using visible light sources, from 447 to 658 nm, a variety of 1-alkenes and 1-alkynes were attached to hydrogen-terminated Si(100) and Si(111) surfaces at room temperature. The presence and the quality of the monolayers were evaluated by static water contact angles, X-ray photoelectron spectroscopy, and IR spectroscopy. Monolayers prepared by thermal, UV light, or visible light initiation were compared. Additionally, the ability of infrared reflection-absorption spectroscopy to study organic monolayers on silicon was explored. A reaction mechanism is discussed on the basis of investigations of the reaction behavior of 1-alkenes with silicon wafers with varying types and levels of doping. Finally, a series of mixed monolayers derived from the mixed solutions of a 1-alkene and an omega-fluoro-1-alkene were investigated to reveal that the composition of the mixed monolayers was directly proportional to the molar ratio of the two compounds in the solutions.

Photochemical attachment of organic monolayers onto H-terminated Si(111): radical chain propagation observed via STM studies.

Photochemical reactions of terminal alkenes with hydrogen-terminated silicon surfaces are being used by many groups to produce covalently attached organic monolayers with a wide range of terminal functionalities. Despite the considerable activity in this area, the mechanism for these reactions has not been definitively established. Here we present STM and HREELS data on a sequence of partially reacted samples, showing the progress of the reaction. The attachment reaction is found to proceed via formation of irregularly shaped islands that appear to grow by a pseudorandom walk process. These data support a radical chain propagation mechanism previously suggested for this reaction. However, since the photons employed here (447 nm) lack sufficient energy for Si-H bond cleavage, an alternate mechanism for initiating the chain reaction appears to be required.

Covalently attached saccharides on silicon surfaces.

This paper presents the first functionalization of silicon surfaces with well-defined, covalently attached monolayers containing saccharides. Two methods were used to this aim: a thermal method (refluxing in mesitylene) and a recently developed, extremely mild photochemical method (irradiation with 447 nm at room temperature). The results were analyzed by FT-IR and angle-resolved X-ray photoelectron spectroscopy. The use of a two-dimensional detector in ARXPS allows for unparalleled, subnanometer resolution in the determination of the elemental composition of monolayers. Even for monolayers with a total thickness of only approximately 1.5 nm, a clear elemental depth profile can be obtained. Such analyses display for sialic acid-containing monolayers that the mild photochemical attachment does not destroy the (rather fragile) sialic acid moiety and that the sugar is present at the top of the monolayer and thus available for biological interactions.

Interference-free determination of trace levels of gold and palladium in geological and metallurgical samples by flame atomic absorption spectrometry coupled with a flow injection on-line microcolumn preconcentration and separation system.

A simple and highly selective method was developed for the routine determination of trace or ultratrace amounts of gold and palladium in geological and metallurgical samples. The method uses flow injection on-line preconcentration and separation with determination by flame atomic absorption spectrometry. Au and Pd in the sample are adsorbed on a 2-mercaptopyrimidine chemically modified silica gel (MPMSG) packed microcolumn in a 0.50M HCl medium and then eluted with 0.5 or 1.0% thiourea solution. The eluates are introduced into the flame atomic absorption spectrometer directly. With the use of a 0.85 mL microcolumn (about 0.14 g MPMSG packed), the present system tolerated concentrations of common base metal ions up to 25.0 mg/mL and concentrations of anions up to 100.0 mg/mL when Au(III) at 0.100 microg/mL and Pd(II) at 0.200 microg/mL were preconcentrated for 60 s with a sample flow rate of 5.0 mL/min. The limits of detection were 3.1 ng/mL for Au(III) and 6.1 ng/mL for Pd(II) with relative standard deviations of < or = 2.5%. The analytical results obtained by the proposed method for geological and metallurgical samples were in good agreement with the certified values.

On-line separation and preconcentration of silver ion on amidino-thiourea immobilized glass beads packing in flow injection analysis with atomic absorption spectrometric detection.

Amidino-thiourea immobilized glass beads (AGB I) were prepared and used as the microcolumn packing for the flow injection (FI) on-line separation and preconcentration of Ag(I) coupled with atomic absorption spectrometry (AAS) determination. Base metal ions and anions with a concentration of 2.0 mg mL(-1) had no interference with the determination of Ag(I). The limit of detection (LOD) of Ag(I) for a preconcentration time of 60 s with a sampling flow rate of 5.0 mL min(-1) for 40.0 ng mL(-1) of Ag(I) were 0.50 ng mL(-1) with the peak-height absorbance mode and 1.26 ng mL(-1) with the peak-area absorbance mode, respectively. The relative standard deviations (RSD) of 7 replicate determinations were 0.9% and 0.7% for the peak-height absorbance (H) and the peak-area absorbance (A), respectively. The method was successfully applied to the determination of Ag(I) in ore samples.