Mammographic Density Assessment by Artificial Intelligence-Based Computer-Assisted Diagnosis: A Comparison with Automated Volumetric Assessment.

We evaluated and compared the mammographic density assessment of an artificial intelligence-based computer-assisted diagnosis (AI-CAD) program using inter-rater agreements between radiologists and an automated density assessment program. Between March and May 2020, 488 consecutive mammograms of 488 patients (56.2 ± 10.9 years) were collected from a single institution. We assigned four classes of mammographic density based on BI-RADS (Breast Imaging Reporting and Data System) using commercial AI-CAD (Lunit INSIGHT MMG), and compared inter-rater agreements between radiologists, AI-CAD, and another commercial automated density assessment program (Volpara®). The inter-rater agreement between AI-CAD and the reader consensus was 0.52 with a matched rate of 68.2% (333/488). The inter-rater agreement between Volpara® and the reader consensus was similar to AI-CAD at 0.50 with a matched rate of 62.7% (306/488). The inter-rater agreement between AI-CAD and Volpara® was 0.54 with a matched rate of 61.5% (300/488). In conclusion, density assessments by AI-CAD showed fair agreement with those of radiologists, similar to the agreement between the commercial automated density assessment program and radiologists.

Microstructure and Mechanical Properties of Functional Graded Ti-Al-Si-N-O Nanocomposite Films Deposited by Filtered Arc Ion Plating Technique.

Functional graded Ti-Al-Si-N-O nanocomposite films were deposited onto WC-Co substrate by a filtered arc ion plating system using TiAl and TiSi composite targets under N2/Ar atmosphere. XRD and XPS analyses revealed that the synthesized Ti-Al-Si-N-O films were nanocomposite consisting of nanosized (Ti, Al, Si)N crystallites embedded in an amorphous Si3N4/SiO2 matrix. The hardness of the Ti-Al-Si-N-O films exhibited the maximum hardness values of ~47 GPa at a Si content of ~5.63 at.% due to the microstructural change to a nanocomposite as well as the solid-solution hardening. Besides, Ti-Al-Si-N-O film with Si content of around 5.63 at.% also showed perfect adhesive strength value of 105.3 N. These excellent mechanical properties of Ti-Al-Si-N-O films could be help to improve the performance of machining tools and cutting tools with application of the film. A comparative study on microstructural characteristics among Ti-Al-Si-N-O films with various Si contents is reported in this paper.

Echo-Doppler-derived indexes of ventricular stiffness and ventriculo-arterial interaction as predictors of new-onset atrial fibrillation in patients with heart failure.

BACKGROUND: Atrial fibrillation (AF) is common in patients with heart failure (HF) and worsens their prognosis. Vulnerability to changes in loading is an important factor in the development of AF and is strongly influenced by ventricular stiffness and ventriculo-arterial interaction. The aim of this study was to investigate predictors of AF development in patients with HF. METHODS: We studied 349 patients with stable HF. The following parameters of ventricular stiffness and ventriculo-arterial interaction were derived from echo-Doppler measurements: left ventricular (LV) diastolic elastance (Ed), effective arterial elastance (Ea), LV end-systolic elastance (Ees) and ventricular-vascular coupling index (VVI). RESULTS: AF occurred in 57 (16.3%) patients over a median follow up of 30.3 months. Echo-Doppler-derived parameters of ventricular stiffness and ventriculo-arterial interaction were closely associated with HF severity. Ed was independently associated with AF after adjustment for age, hypertension, diabetes mellitus, and left atrial volume index (hazard ratio [HR] 5.49, p = 0.018). Ea and VVI were also associated with new-onset AF (HR 1.66, p = 0.027, and HR 1.06, p = 0.001, respectively). CONCLUSIONS: Echo-Doppler indexes of ventricular stiffness are closely associated with HF severity. LV diastolic elastance (Ed) is the strongest predictor of new-onset AF in HF patients.

Anomalous rapid defect annihilation in self-assembled nanopatterns by defect melting.

Molecular self-assembly commonly suffers from dense structural defect formation. Spontaneous defect annihilation in block copolymer (BCP) self-assembly is particularly retarded due to significant energy barrier for polymer chain diffusion and structural reorganization. Here we present localized defect melting induced by blending short neutral random copolymer chain as an unusual method to promote the defect annihilation in BCP self-assembled nanopatterns. Chemically neutral short random copolymer chains blended with BCPs are specifically localized and induce local disordered states at structural defect sites in the self-assembled nanopatterns. Such localized "defect melting" relieves the energy penalty for polymer diffusion and morphology reorganization such that spontaneous defect annihilation by mutual coupling is anomalously accelerated upon thermal annealing. Interestingly, neutral random copolymer chain blending also causes morphology-healing self-assembly behavior that can generate large-area highly ordered 10 nm scale nanopattern even upon poorly defined defective prepatterns. Underlying mechanisms of the unusual experimental findings are thoroughly investigated by three-dimensional self-consistent field theory calculation.

MicroRNA-365 inhibits the proliferation of vascular smooth muscle cells by targeting cyclin D1.

Abnormal proliferation of vascular smooth muscle cells (VSMCs) is a common feature of disease progression in atherosclerosis. Cell proliferation is regulated by cell cycle regulatory proteins. MicroRNAs (miR) have been reported to act as important gene regulators and play essential roles in the proliferation and migration of VSMCs in a cardiovascular disease. However, the roles and mechanisms of miRs in VSMCs and neointimal formation are far from being fully understood. In this study, cell cycle-specific cyclin D1 was found to be a potential target of miR-365 by direct binding. Through an in vitro experiment, we showed that exogenous miR-365 overexpression reduced VSMC proliferation and proliferating cell nuclear antigen (PCNA) expression, while miR-365 was observed to block G1/S transition in platelet-derived growth factor-bb (PDGF-bb)-induced VSMCs. In addition, the proliferation of VSMCs by various stimuli, including PDGF-bb, angiotensin II (Ang II), and serum, led to the downregulation of miR-365 expression levels. The expression of miR-365 was confirmed in balloon-injured carotid arteries. Taken together, our results suggest an anti-proliferative role for miR-365 in VSMC proliferation, at least partly via modulating the expression of cyclin D1. Therefore, miR-365 may influence neointimal formation in atherosclerosis patients.

The Effect of Time Spent on Online Gaming on Problematic Game Use in Male: Moderating Effects of Loneliness, Living Alone, and Household Size.

OBJECTIVE: This study aimed to investigate the association between gaming time and problematic game use (PGU) within a large sample of Korean male gamers and to examine the potential moderating effects of loneliness, living alone, and household size. METHODS: This study employed data from 743 male gamers from the National Mental Health Survey 2021, a nationally representative survey of mental illness conducted in South Korea. Self-reported data on the average gaming time per day, severity of PGU, loneliness, living alone, and household size were used. RESULTS: Gaming time was positively associated with PGU and this relationship was significantly moderated by loneliness such that the positive effect of gaming time on PGU was greater when the levels of loneliness were high. The three-way interaction effect of gaming time, loneliness, and living alone was also significant, in that the moderating effect of loneliness on the relationship between gaming time and PGU was significant only in the living alone group. However, household size (i.e., number of housemates) did not moderate the interaction between gaming time and loneliness among gamers living with housemates. CONCLUSION: These results suggest the importance of considering loneliness and living arrangements of male gamers, in addition to gaming time, in identifying and intervening with individuals at heightened risk of PGU.

Computed Tomography Radiomics for Preoperative Prediction of Spread Through Air Spaces in the Early Stage of Surgically Resected Lung Adenocarcinomas.

PURPOSE: To assess the added value of radiomics models from preoperative chest CT in predicting the presence of spread through air spaces (STAS) in the early stage of surgically resected lung adenocarcinomas using multiple validation datasets. MATERIALS AND METHODS: This retrospective study included 550 early-stage surgically resected lung adenocarcinomas in 521 patients, classified into training, test, internal validation, and temporal validation sets (n=211, 90, 91, and 158, respectively). Radiomics features were extracted from the segmented tumors on preoperative chest CT, and a radiomics score (Rad-score) was calculated to predict the presence of STAS. Diagnostic performance of the conventional model and the combined model, based on a combination of conventional and radiomics features, for the diagnosis of the presence of STAS were compared using the area under the curve (AUC) of the receiver operating characteristic curve. RESULTS: Rad-score was significantly higher in the STAS-positive group compared to the STAS-negative group in the training, test, internal, and temporal validation sets. The performance of the combined model was significantly higher than that of the conventional model in the training set {AUC: 0.784 [95% confidence interval (CI): 0.722-0.846] vs. AUC: 0.815 (95% CI: 0.759-0.872), p=0.042}. In the temporal validation set, the combined model showed a significantly higher AUC than that of the conventional model (p=0.001). The combined model showed a higher AUC than the conventional model in the test and internal validation sets, albeit with no statistical significance. CONCLUSION: A quantitative CT radiomics model can assist in the non-invasive prediction of the presence of STAS in the early stage of lung adenocarcinomas.

Sonographic characteristics suggesting papillary thyroid carcinoma according to nodule size.

PURPOSE: To determine differences in ultrasonography (US) features suggesting papillary thyroid carcinoma (PTC) between nodules larger than 10 mm (large lesions) and nodules ≤10 mm in diameter (small lesions). METHODS: We included 1,238 nodules in 1,173 patients that were confirmed through cytology or histopathology between February 2007 and June 2007 in the study. Nodules were divided into large lesions (571 lesions) and small lesions (667 lesions). Sonographic features were defined as composition, echogenicity, margin, calcifications, shape, and vascularity. Logistic regression analyses were performed to determine the odds ratios (OR) of each feature to predict PTC. RESULTS: On multivariate analysis, irregular margin (OR = 37.788, P < 0.001), microcalcifications (OR = 17.799, P < 0.001), microlobulated margin (OR = 10.385, P < 0.001), and no vascularity (OR = 5.975, P < 0.001) were independent factors for PTC in the large lesions and irregular margin (OR = 7.185, P < 0.001), microlobulated margin (OR = 5.952, P < 0.001), microcalcifications (OR = 3.722, P < 0.001), marked hypoechogenicity (OR = 2.873, P = 0.004), and taller than wide shape (OR = 2.698, P < 0.001) were independent factors for PTC in the small lesions. CONCLUSIONS: The OR of each US finding for predicting PTC is different between large and small lesions. Therefore, it would be helpful to weight certain US features according to nodule size when reporting thyroid nodules with different risks of PTC.

Physicochemical properties and antioxidant activity of colored peppers (Capsicum annuum L.).

Peppers are spices consumed all around the world. This study evaluated the physicochemical properties and antioxidant activities of red, orange, yellow, green, and purple peppers. Total capsaicinoids showed the highest concentration in the green pepper (2416.50 µg/g). Vitamin C showed similar concentrations in all peppers (28.90-30.95 mg/g), except for the purple pepper (25.59 mg/g). Chlorophyll was abundant in the green and the purple peppers (280.36 and 102.13 mg/100 g). Total carotenoid was abundant in the red and the orange peppers (237.04 and 276.94 mg/100 g). Total anthocyanin was detected only in the purple pepper (67.13 mg/100 g). Total flavonoid showed a high concentration in the green and the purple peppers (24.27 and 22.27 CAE mg/g). The yellow pepper showed the highest antioxidant activity according to total polyphenol, DPPH radical scavenging activity, ABTS radical scavenging activity and reducing power assays. Therefore, peppers showed potential for the development of functional food materials.

Phenolic compounds, antioxidant capacity, and α-amylase and α-glucosidase inhibitory activity of ethanol extracts of perilla seed meal.

Perilla frutescens is a medicinal herb that is commonly cultivated in Asian countries. Perilla seed is extensively pressed for cooking oil extraction. However, phenolic chemicals are still abundant in pressed perilla seed meal (PSM), which was previously thought to be useless after oil extraction. In our study, PSM was extracted using five solvents (water and 25%, 50%, 75%, and 100% ethanol) based on different ethanol concentrations, and its antioxidant activity, phenolic compounds, and inhibitory effects against key enzymes related to diabetes mellitus were evaluated. The 75% ethanol extract had higher phenolic (105.58 mg GAE/g DW) and flavonoid (66.52 mg QE/g DW) contents and showed better antioxidant and inhibitory effects against α-glucosidase and α-amylase. Analysis of the phenolic compounds of the five extracts by HPLC indicated the presence of apigenin, rosmarinic acid, benzoic acid, caffeic acid, and vanillic acid. Therefore, because of its high antioxidant activity and inhibitory capacity against enzymes relevant to diabetes, the 75% ethanol extract of perilla seed meal has the most potential to be used as a functional or nutraceutical food in the prevention and treatment of oxidation and diabetes.

Incidentally found resectable lung cancer with the usage of artificial intelligence on chest radiographs.

PURPOSE: Detection of early lung cancer using chest radiograph remains challenging. We aimed to highlight the benefit of using artificial intelligence (AI) in chest radiograph with regard to its role in the unexpected detection of resectable early lung cancer. MATERIALS AND METHODS: Patients with pathologically proven resectable lung cancer from March 2020 to February 2022 were retrospectively analyzed. Among them, we included patients with incidentally detected resectable lung cancer. Because commercially available AI-based lesion detection software was integrated for all chest radiographs in our hospital, we reviewed the clinical process of detecting lung cancer using AI in chest radiographs. RESULTS: Among the 75 patients with pathologically proven resectable lung cancer, 13 (17.3%) had incidentally discovered lung cancer with a median size of 2.6 cm. Eight patients underwent chest radiograph for the evaluation of extrapulmonary diseases, while five underwent radiograph in preparation of an operation or procedure concerning other body parts. All lesions were detected as nodules by the AI-based software, and the median abnormality score for the nodules was 78%. Eight patients (61.5%) consulted a pulmonologist promptly on the same day when the chest radiograph was taken and before they received the radiologist's official report. Total and invasive sizes of the part-solid nodules were 2.3-3.3 cm and 0.75-2.2 cm, respectively. CONCLUSION: This study demonstrates actual cases of unexpectedly detected resectable early lung cancer using AI-based lesion detection software. Our results suggest that AI is beneficial for incidental detection of early lung cancer in chest radiographs.

Exploring trajectories of depressive symptoms in North Korean defectors: A latent class mixed analysis.

Background: North Korean defectors (NKDs) are known to be vulnerable to depression due to the influence of various psychosocial factors during their settlement process. Therefore, this study aimed to explore different trajectories of depressive symptoms in NKDs and identify predictors of the worsening of depressive symptoms. In particular, the focus was on whether posttraumatic stress disorder (PTSD) functions as a significant predictor. Methods: Participants consisted of 300 NKDs who settled in South Korea within 3 years of entering in the country. Five waves of longitudinal data collected from 2016 to 2019 were used. In this study, the North Korean Composite International Diagnostic Interview (NK-CIDI), a diagnostic interview tool, was conducted at baseline and depressive symptoms were measured at each wave. Trajectory identification was based on latent class mixed modeling. Logistic regression was used to extract the significant factors predicting a high/increasing depressive symptom trajectory. Results: Two trajectories of depressive symptoms were identified: "low/stable symptom" (76.7% of participants) and "high/increasing symptom" (23.3% of participants). Predictors of the high/increasing symptom group were being female and a low use of mental health services. Generalized anxiety disorder, social phobia, and alcohol dependence acted as significant predictors. Although PTSD was not a significant predictor, self-reported PTSD symptom scores were high in the high/increasing symptom group. Conclusions: Identifying the trajectories of depressive symptoms in NKDs helps identify the risk factors of clinically vulnerable groups. In the process of establishing government-level interventions, it may be helpful to create a therapeutic environment. In addition, when evaluating initial psychiatric problems, it is important to primarily consider NKDs' anxiety levels and alcohol problems. There should also be an appropriate consideration of PTSD symptoms.

Changes in the Physicochemical Properties, Antioxidant Activity and Metabolite Analysis of Black Elephant Garlic (Allium ampeloprasum L.) during Aging Period.

This study investigated the effects of the aging period on the black elephant garlic (Allium ampeloprasum L.) manufacturing process. Black elephant garlic is a processed elephant garlic product prepared by high-temperature and high-humidity treatment for 40 days. The proximate composition (moisture, crude lipid, crude protein, carbohydrate, and ash), minerals, color values, reducing sugars, pH, total polyphenol contents, total flavonoid contents and antioxidant activities of elephant garlic and black elephant garlic were evaluated. The browning intensity of elephant garlic increased with the aging period, but the browning reaction terminated after aging for 30 days, exhibiting the same browning level. Reducing sugars increased over the aging period until 20 days, and then decreased with the aging period, in contrast to the pH, which decreased from 6.47 to 3.68 over the aging period. Antioxidant components, including the total polyphenol and total flavonoid contents of black elephant garlic, increased significantly until day 30 of aging. From the metabolite profiles determined through GC/MS analysis, it was confirmed that primary metabolites related to antioxidant components, such as lactic acid and 5-hydroxymethyl-2-furoic acid, were generated during the aging process of elephant garlic.

US-guided diffuse optical tomography for breast lesions: the reliability of clinical experience.

PURPOSE: To prospectively assess the reliability of US-guided diffuse optical tomography (US-DOT) using interobserver agreement for the diagnosis of breast lesions with individual real-time imaging and to assess the interobserver agreement of conventional sonography (US) combined with US-DOT for differentiation between benignity and malignancy breast lesions. MATERIALS AND METHODS: An Institutional Review Board approved this study, and all subjects provided written informed consent. 122 breast lesions in 111 patients evaluated with US-guided core biopsy were included. Assessments with US and US-DOT for cases subjected to biopsy were obtained by two radiologists using individual real-time imaging prior to biopsy and were prospectively recorded by each performer. With DOT, the total haemoglobin concentration (THC) for each breast lesion was measured. Histopathological results from US-guided biopsies were used as a reference standard. To assess measurement interobserver agreement, the intraclass correlation coefficient (ICC) and the Bland-Altman plot were used for THC in US-DOT and the kappa values and ROC analysis were used to evaluate the diagnostic performances of the US BI-RADS final assessment in US and combined US and US-DOT. RESULTS: Of 122 US-guided core biopsied lesions, 83 (68.0%) were diagnosed as benign, and 39 (32.0%) as malignant. Excellent correlation was seen in the THC in US-DOT (ICC score 0.796; 95% confidence interval, 0.708-0.857). The interobserver agreement in BI-RADS final assessment with US and US-DOT (almost perfect; κ = 0.8618) was improved compared with that of US (substantial agreement, κ = 0.6574). However, the overall areas under the ROC curve did not show significant differences between US and combined US and US-DOT, 0.8894 and 0.8975, respectively (P = 0.981). CONCLUSIONS: The reliability of THC in US-DOT showed excellent correlation in overall real-time performance. Although the inter-observer agreement for BI-RADS final assessment of US was improved by using US-DOT, the performances of radiologists with respect to the characterization of breast masses as benign or malignant were not significantly improved with US-DOT.

Interobserver variability of ultrasound elastography: how it affects the diagnosis of breast lesions.

OBJECTIVE: The purpose of this article is to evaluate the interobserver variability of elastography on real-time ultrasound and how it influences the agreement of final assessment on ultrasound. SUBJECTS AND METHODS: From April to May 2009, 65 breast lesions of 53 patients (mean age, 42.6 years; range, 18-72 years) who underwent ultrasound-guided core biopsy were included in this study. Ultrasound and elastography images of the lesion subjected to biopsy were obtained and prospectively analyzed by three radiologists with individual real-time image scanning prior to biopsy. Each radiologist recorded final ultrasound BI-RADS assessments using ultrasound and combined ultrasound and elastography and the fat-to-lesion ratio and elasticity score. The histopathologic results obtained from ultrasound-guided core biopsy or excision were used as the reference standard. Diagnostic performances and interobserver agreement were analyzed. RESULTS: Of the 65 lesions, 43 (66.2%) were benign, and 22 (33.8%) were malignant. Specificity (20.2-33.3%), positive predictive value (38.7-45.1%), and accuracy (46.7-55.4%) were significantly improved in combined ultrasound and elastography (p < 0.001). Area under the curve (AUC) values for all three performers did not show significant differences in ultrasound (AUC, 0.959) and combined ultrasound and elastography (AUC, 0.957) (p = 0.92). Interobserver agreement was not improved with combined ultrasound and elastography (κ = 0.25) in comparison to ultrasound only (κ = 0.37). Interobserver agreement of real-time elastography was fair in both fat-to-lesion ratio (intraclass correlation coefficient score, 0.25) and elasticity score (κ = 0.28). Moderate agreement (κ = 0.46) was seen with static elastography. CONCLUSION: Elastography improves the specificity, positive predictive value, and accuracy of ultrasound. However, significant interobserver variability exists, with real-time elastographic performance showing fair agreement.

Attitude and knowledge of physicians about cancer pain management: young doctors of South Korea in their early career.

OBJECTIVE: This study is aimed at evaluating the attitude and knowledge about the optimal use of opioids and finding out the barriers to cancer pain management especially for young doctors in South Korea. METHODS: A survey through questionnaire form was conducted on 1204 physicians. Physicians were grouped by their medical specialties and personal characteristics. Specialties were grouped into internal medicine and family medicine doctors, surgeons, anesthesiologists, pediatricians, other board holders and general physicians. Personal characteristics were grouped by their past experiences and current surroundings. RESULTS: Though many doctors thought that they were fairly well educated for pain management strategy, a large population of physicians showed a negative attitude and inadequate knowledge status about cancer pain management. The degree of attitude and knowledge status was different as their specialties and personal experiences. The factors that affected doctors' attitude and knowledge were: (i) medical specialty, (ii) past history of using practical pain assessment tool, (iii) self-perception of knowledge status about pain management, (iv) experience of prescribing opioids, (v) experience of education for cancer pain management. Although many physicians had a passive attitude in prescribing opioid analgesics, they are willingly open to use opioids for cancer pain management in the future. The most important perceived barriers to optimal cancer pain management were the fear for risk of tolerance, drug addiction, side effects of opioid analgesics and knowledge deficit about opioid analgesics. CONCLUSIONS: From this study, we found that further education and practical training will be needed for adequate cancer pain management for young physicians in their early career.

Community-based intervention to promote breast cancer awareness and screening: the Korean experience.

BACKGROUND: There are many differences in culture, community identity, community participation, and ownership between communities in Western and Asian countries; thus, it is difficult to adopt the results of community intervention studies from Western countries. In this study, we conducted a multicity, multicomponent community intervention trial to correct breast cancer myths and promote screening mammography for women living in an urban community in Korea. METHODS: A 6-month, 2-city community intervention trial was conducted. In the intervention city, 480 women were surveyed at baseline and 7 months later to evaluate the effects of the intervention program. Strategies implemented in the intervention city included community outreach and clinic and pharmacy-based in-reach strategies. RESULTS: This study showed a 20.4-percentage-point decrease in myths about the link between cancer and breast size, a 19.2-percentage-point decrease in myths concerning mammography costs, and a 14.1-percentage-point increase in intention to undergo screening mammography. We also saw a 23.4-percentage-point increase in the proportion of women at the action stage of the transtheoretical model in the intervention city. In the comparison city, smaller decreases and increases were observed. CONCLUSIONS: Our study showed the value of an intervention study aimed at reducing belief in breast cancer myths in an urban community in Korea. The invention also made women more likely to undergo mammography in future.

Delayed occurrence of spinal arachnoiditis following a caudal block.

CONTEXT: Spinal arachnoiditis is a rare disease caused by fibrosis and adhesion of the arachnoid membrane due to chronic inflammation. The causes of arachnoiditis are infection, spinal surgery, intraspinal injection of steroid or myelography dye, and spinal anesthesia. METHOD: Case report. FINDINGS: A 60-year-old woman presented with progressive weakness and sensory change of both legs and urinary symptoms. She had received a single caudal block 6 months before symptom onset. Magnetic resonance imaging of the thoraco-lumbar spine showed an intradural extramedullary tumor at the T5-T7 level. She underwent laminectomy and tumor resection. The pathological finding was arachnoiditis. After surgery, a rehabilitation program of strengthening exercises of both lower extremities and gait training was started. At 2-month follow-up, she was able to walk with orthoses and performed daily activities with minimal assistance. CONCLUSION: Symptoms of spinal arachnoiditis occurred 6 months after a single caudal block in this woman. Clinicians should be aware of this possible delayed complication.

Hazardous effects of eight years of application of four organic waste materials on earthworm numbers and biomass in field lysimeters.

The hazardous effects on the earthworm numbers and biomass of eight consecutive yearly applications of three levels (12.5, 25, and 50 tons of dry matter/ha/y) of four different organic sludges (municipal sewage, industrial sewage, alcohol fermentation processing, and leather processing) to earthworm-free soils were examined using field lysimeters. Results were compared with those of pig manure compost (PMC)-treated soil. Of five species (Amynthas agrestis, A. sangyeoli, A. hupeiensis, Drawida koreana, and D. japonica) from 390 adult specimens collected 4 and 8 years after treatment, the number of species appeared to be lower in sludge-treated soils than in PMC-treated soils. Earthworm populations and biomass were correlated negatively with the pollution index [∑(heavy-metal concentration in soil/tolerable level)/number of heavy metal] 4 and 8 years after treatment. These results suggest that the long-term application of these sludges, particularly from industrial sewage and leather processing, might affect adversely the establishment of Megascolecid and Moniligastrid earthworms in field conditions.

Shift of Dominant Species in Plant Community and Soil Chemical Properties Shape Soil Bacterial Community Characteristics and Putative Functions: A Case Study on Topographic Variation in a Mountain Pasture.

Reducing management intensity according to the topography of pastures can change the dominant plant species from sown forages to weeds. It is unclear how changes in species dominance in plant community drive spatial variation in soil bacterial community characteristics and functions in association with edaphic condition. Analysing separately the effects of both plant communities and soil chemical properties on bacterial community is crucial for understanding the biogeographic process at a small scale. In this paper, we investigated soil bacterial responses in five plant communities (two forage and three weed), where >65% of the coverage was by one or two species. The structure and composition of the bacterial communities in the different microbiome were analysed using sequencing and their characteristics were assessed using the Functional Annotation of Prokaryotic Taxa (FAPROTAX) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Firmicutes and Planctomycetes responded only to one specific plant community, and each plant community harboured unique operational taxonomic units (OTUs) at the species level. There were a large percentage of uniquely absent OTUs for specific plant communities, suggesting that a negative effect is critical in the relationship between plants and bacteria. Bacterial diversity indices were influenced more by soil chemical properties than by plant communities. Some putative functions related to C and N recycling including nitrogen fixation were correlated with pH, electrical conductivity (EC) and nutrient levels, and this also implied that some biological functions, such as ureolysis and carbon metabolism, may decline when fertilisation intensity is reduced. Taken together, these results suggest that a shift of dominant species in plant community exerts individual effects on the bacterial community composition, which is different from the effect of soil chemical properties.