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Diatoms are widely used as bio-indicators in water quality monitoring and ecological status assessment. Compare to chemical variables, the effects of hydrological variables on diatom dynamics have been rarely reported. In this study, we aimed to examine dynamics of diatoms based on the classification of a morphological trait (cell size) and to investigate the relationship between the diatom community and selected chemical and hydrological variables. We collected 339 daily-mixed samples by using an auto-sampler, from which we recorded 113 diatom taxa from 45 genera. Analysis of morphological trait showed variations among cell size classes throughout the year with big cells in winter and spring while small cells dominated in summer and autumn. Redundancy analysis (RDA) and partial RDA indicated that chemical and hydrological variables could jointly explain 50.2% of the diatom community variation, in which chemical variables explain 36.5% and hydrological variables explain 12.9%. The most important chemical variables were Orthophosphate-phosphorus (PO 4 -P) and Silicon (Si 2+ ) concentrations, while the most significant hydrological variables were antecedent precipitation index (API) and base flow. We conclude that besides chemical variables (nutrients and metal ions) hydrological variables showed also remarkable effects on the diatom community variation, especially during wet conditions. A key implication of our findings for freshwater management is that future bio-monitoring protocols should take hydrological variables into consideration. [ABSTRACT FROM AUTHOR]

• Longer sampling intervals lead to a bigger error of the load estimation. • The sampling frequency should be decided, respectively, for different elements based on the autocorrelation. • Both periodic sampling of discharge and nutrients leads to unreliable results. • The best sampling strategy for load estimation is a combination of continuous discharge monitoring and periodic nutrient concentration measurements. The transport of nutrients into water bodies is one of the main causes of water eutrophication. It is therefore important to estimate the loads of nutrients. Discharge and nutrient concentrations are the fundamental elements to estimate the loads of nutrients, the latter can be affected by sampling strategies. As conducting sampling campaign and laboratory analysis are both expensive, it is necessary to find the best effective sampling strategy. The aim of this paper is to show how autocorrelation and standard statistical methods can be used to test the effects of different sampling strategies on the nutrient load estimation and to find the optimal sampling strategy. The data set in this study is from the 50 km² Kielstau catchment, a UNESCO demo site for ecohydrology in Northern Germany and consists of 14 years daily values of climate, hydrology, and water quality from 2006 to 2019. We calculated the autocorrelation (AC) of discharge (Q), precipitation, Nitrate-Nitrogen (NO 3 -N) and total Phosphorus (Ptot). Then we tested the effects of sampling intervals from 7 to 56 days (1–8 weeks) on the nutrient loads. Our results showed a high AC of Q and NO 3 -N for a long period, but the AC of Ptot and precipitation decreased very fast. An increase of the sampling interval (less frequent) increased the error of estimating the concentrations and loads. Consequently, we recommend that (1) the optimal sampling strategy for nutrient load estimation in an agriculture-dominant catchment should be continuously monitoring discharge combined with periodic grabbed samples; (2) the sampling frequency for NO 3 -N is suggested to be monthly (every 28 days) and for Ptot weekly (every 7 days). The information will help those tasked with catchment monitoring to design appropriate sampling strategy to ensure adequate data for nutrients load estimation in lowland rivers. [ABSTRACT FROM AUTHOR]

Objective Methods Results Conclusions This retrospective study involving a large dataset of unilateral multifocal papillary thyroid carcinoma (UM‐PTC) sought to identify factors that predict central lymph node metastases (CLNM) in patients.We identified a cohort of 158 patients who underwent cervical ultrasonography followed by UM‐PTC diagnosis based on postoperative pathology. The relationship between CLNM and UM‐PTC clinical ultrasound features was evaluated using univariate and multivariate analyses. Receiver operating characteristic (ROC) curve analysis was used to determine the ability of total tumor diameter (TTD) to predict CLNM.Among the 158 UM‐PTC patients, the incidence of CLNM was 29.7% (47/158). Univariate and multivariate analyses revealed that a number of similarity of sonographic features (NSSF) ≥4 (odds ratio [OR] = 11.335, 95% confidence interval [CI]: 3.95–32.50, p = 0.000), microcalcifications (OR = 3.54, 95% CI: 1.30–9.70, p = 0.014), a TTD of ≥2 cm (OR = 4.48, 95% CI: 1.62–12.34, p = 0.004), number of nodules ≥3 (OR = 13.17, 95% CI: 3.24–53.52, p = 0.000), and Lateral cervical lymph node metastasis (LLNM) (OR = 5.57, 95% CI: 1.59–19.48, p = 0.007) were independently associated with CLNM in UM‐PTC. ROC curve analysis revealed that the TTD cut‐off of 1.795 cm had a sensitivity of 0.723 and a specificity of 0.676 for predicting CLNM.Patients with UM‐PTC are at high risk of CLNM. NSSF ≥4, microcalcifications, TTD of ≥2 cm, LLNM, and a number of nodules ≥3 were independently associated with CLNM. Our data show that ultrasound may guide surgical decisions in the treatment of UM‐PTC. [ABSTRACT FROM AUTHOR]

BACKGROUND: Female breast cancer has surpassed lung cancer as the most commonly diagnosed cancer, with an estimated 2.3 million new cases (11.7%) in the global cancer statistics 2020. OBJECTIVE: To evaluate the diagnostic value of ultrasound elastography combined with multi-parameters in differentiating category 4 benign and malignant lesions in the breast imaging reporting and data system (BI-RADS). METHODS: This study retrospectively analyzed 206 patients (213 breast lesions) who visited the Department of Breast Surgery and underwent a breast core needle biopsy in the Department of Ultrasound in Peking University First hospital from April to December 2019. The shear wave velocity (SWV) values were collected at the following locations by virtual touch tissue imaging quantification (VTIQ): breast lesion interior, breast lesion margin, surrounding glands, and surrounding fat. Simultaneously, the strain ratio (SR) of breast lesions to glands and the area ratio (AR) of breast lesions were collected under strain elastography and a two-dimensional ultrasound mode. RESULTS: Univariate analysis found that the SWV value, measured by ultrasound elastography parameters, and the AR between the elasticity and the two-dimensional ultrasound breast lesions showed statistical differences when differentiating benign and malignant lesions (p < 0.05). Binary logistic regression analysis found that the SWV values of the lesion interior and the surrounding glands were statistically significant. The joint predictors were calculated and analyzed by Receiver Operating Characteristic (ROC), and it was found that the joint predictors and the SWV values of the lesion interior have great diagnostic value. The cut-off value, sensitivity and specificity of the joint predictor and the SWV value of the lesion interior were > 3.65, 88.35% and 76.36% and > 5.55 m/s, 79.61% and 82.73%, respectively. CONCLUSIONS: Ultrasound elastography combined with multi-parameters has good diagnostic value in differentiating BI-RADS 4 breast lesions. [ABSTRACT FROM AUTHOR]

A sound understanding of the community changes over time and its driving forces is at the centre of biodiversity conservation and ecology research. In this study, we examined: (i) the relative roles of turnover and nestedness components to trait‐ and taxonomy‐based temporal beta diversity of riverine diatoms; (ii) whether trait‐based temporal beta diversity provides complementary information to taxonomy‐based temporal beta diversity; (iii) the relative roles of hydrology (e.g. discharge, antecedent precipitation index), metal ions (e.g. Mg2+, Si2+) and nutrients (e.g. nitrogen, orthophosphate) to the both facets of temporal beta diversity and their components (i.e. total beta diversity, turnover and nestedness); and (iv) whether inclusion of environment regimes increase their explained variations.A total of 338 daily samples of riverine diatom communities were collected. We employed Mantel tests to evaluate the complementarities between trait‐ and taxonomy‐based temporal beta diversity. Using distance‐based redundancy analysis (db‐RDA) and variation partitioning, we investigated the relative roles of hydrology, metal ions and nutrients to each facet of temporal beta diversity and its components.Correlations between trait‐ and taxonomy‐based temporal beta diversity and their components were weak, which showed their complementary ecological information. Taxonomy‐based total beta diversity had a high contribution by turnover component, whereas trait‐based total beta diversity was largely driven by nestedness component. Results of variation partitioning demonstrated that the pure and shared fractions of hydrology, metal ions and nutrient differed among the components of trait‐ and taxonomy‐based temporal beta diversity. Furthermore, addition of environment regimes could dramatically increase the explained variation of temporal beta diversity and its components.Synthesis. Our results highlighted the importance of the two facets of temporal beta diversity as well as their decomposition for exploring diversity patterns of riverine diatoms in relation to abiotic factors, particularly the environment regimes. Although a high temporal taxonomic divergence was detected, the high level of temporal trait convergence indicated that species turnover with similar biological traits occurred during our study period. Our study, for the first time, provides a new perspective into temporal beta diversity of daily riverine diatom communities, which has not yet been documented by previous freshwater studies. [ABSTRACT FROM AUTHOR]

Highlights • Phytoplankton community highly varied among sub-basins and hydrological periods. • Medium density residential land use acted as a critical driver during wet period. • The skewness of 7 days discharge emerged as a key driver for benthic diatom. • Microcystis was more closely related to phosphorous and lacustrine zone. Abstract Rivers and related freshwater ecosystems are facing increasing natural disturbance and anthropogenic stressors. Understanding the key ecological processes that govern the riverine biota in aquatic ecosystems under multiple pressures has crucial importance. However, there is still insufficient knowledge in quantifying of stressors interactions. Moreover, the understanding of the responses of riverine phytoplankton to multiple stressors is still scarce from catchment aspect. As an interdisciplinary study, the catchment hydrological processes were linked to ecological responses in this study, and we chose phytoplankton functional groups (PFGs) instead of taxonomic classifications of algae to examine their responses to land-use pattern (L), hydrological regime (H), and physicochemical condition (P) across two contrasting hydrological periods (dry, wet). The traits-based phytoplankton functional groups are highly suggested as robust bio-indicators for better understanding the current ecological status. The hydrological regime was described by a matrix indices of hydrological alteration based on the outputs of a well-established ecohydrological model (SWAT). The results from variation partitioning analysis showed that P and H dominate during the dry period and P in high flows. Structural equation models (SEM) showed that the skewness of 7 days discharge emerged as a key driver of H, and had always an indirect effect on functional group TB (benthic diatoms) during both hydrological periods. The functional group M (mainly composed by Microcystis) has directly related to phosphorous in both periods, while indirectly to L of urban area in high flow period, and water bodies in low flow period. This study emphasized that climate change and anthropogenic activities such as altering flow regime and land-use pattern affect directly or indirectly riverine phytoplankton via physicochemical conditions. In addition, our findings highlighted that biomonitoring activities require detailed investigation in different hydrological periods. SEM is recommended for improved understanding of phytoplankton responses to the changing environment, and for future studies to fulfill the increasing demand for sustainable watershed management regarding aquatic biota. [ABSTRACT FROM AUTHOR]

This study investigated the effects of different concen- concentrations of oxygen exposure on the morphology and function of N9 microglia and analyzed its mechanisms. N9 microglia were cultured under the condition of high (95% O2 and 5% CO2), normal (95% air and 5% CO2) and low oxygen (95% CO2 and 5% O2) concentrations. The cell morphologies were observed under inverted phase contrast microscope after 24 h. Flow cytometry was applied to detect cell survival and apoptotic rate. The mRNA and protein expression levels of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) were detected by reverse transcription-polymerase chain reaction (RT-PCR) and western blot analysis, respectively. The results showed that, N9 microglial apoptotic rates in hyperoxia and hypoxia conditions were significantly higher than those in the normal group (P<0.05) and the apoptosis rate in the hypoxia group was higher than that in the hyperoxia group (P<0.05). The mRNA and protein expression levels of IL-1β and TNF-α in the hyperoxia and hypoxia groups were significantly higher than those in the normal group (P<0.05) and the mRNA and protein expression levels in hypoxia group were higher than those in the hyperoxia group (P<0.05). Therefore, N9 microglia cultured under hyperoxia and hypoxia conditions can be activated, enhancing pro-inflammatory response and inducing cell apoptosis. The mechanism may be that the secretion of neurotoxic factors IL-1β and TNF-α is involved in these responses. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the effects of flurbiprofen on serum level of interleukin-6 (IL-6), prostacyclin (PGI2) and corticosteroid A2 (TXA2) in patients with bone metastases of cancer. A total of 210 patients with bone metastasis of cancer were randomly divided into two groups: Flurbiprofen axetil analgesia group (group A) and dezocine analgesia group (group B), 105 cases in each group. The analgesic effect was evaluated using visual analogue scale (VAS) scoring system at 1, 12, 24 and 48 h after treatment. Serum levels of IL-6, PGI2 and TXA2 at 12 and 24 h after treatment were detected using double-antibody sandwich enzymelinked immunosorbent assay. No significant differences in VAS scores were found between the two groups at 1, 12, 24 and 48 h after treatment, and no gastrointestinal adverse events and abnormal bleeding were observed. No significant differences in the serum levels of IL-6 were found between the two groups at 12 and 24 h after treatment. Significantly lower serum levels of TXA2 and PGI2 were found in group A compared to group B at 12 and 24 h after treatment (P<0.05). Serum level of PGI2 was positively correlated with serum level of TXA2 (r=0.7212, P<0.05) and VAS score (r=0.7159, P<0.05). Serum level of IL-6 was positively correlated with VAS score (r=0.7997, P<0.05). The results show that flurbiprofen axetil can effectively relieve pain in patients with bone metastases of cancer, can inhibit platelet activation, adhesion and aggregation, and reduce the formation of deep vein thrombosis, and can inhibit stress response and inflammatory response in the body. [ABSTRACT FROM AUTHOR]

There has been increasing interest in diatom-based bio-assessment but we still lack a comprehensive understanding of how to capture diatoms' temporal dynamics with an appropriate sampling frequency (ASF). To cover this research gap, we collected and analyzed daily riverine diatom samples over a 1-year period (25 April 2013-30 April 2014) at the outlet of a German lowland river. The samples were classified into five clusters (1-5) by a Kohonen Self-Organizing Map (SOM) method based on similarity between species compositions over time. ASFs were determined to be 25 days at Cluster 2 (June-July 2013) and 13 days at Cluster 5 (February-April 2014), whereas no specific ASFs were found at Cluster 1 (April-May 2013), 3 (August-November 2013) (>30 days) and Cluster 4 (December 2013 - January 2014) (<1 day). ASFs showed dramatic seasonality and were negatively related to hydrological wetness conditions, suggesting that sampling interval should be reduced with increasing catchment wetness. A key implication of our findings for freshwater management is that long-term bio-monitoring protocols should be developed with the knowledge of tracking algal temporal dynamics with an appropriate sampling frequency. [ABSTRACT FROM AUTHOR]

Highlights: [•] Structure and spectroscopic features of Ti-MWW are calculated by DFT and TD-DFT. [•] Ti4+ prefers to locate at T1 and T3 sites in form of Ti(OSi)4. [•] The 960cm−1 band is attributed to the out-of-phase stretching of Ti(OSi)4. [•] The excitation at 210nm is contributed by electronic transition of p(O)→ π ∗(Ti–O). [Copyright &y& Elsevier]