High-density tailings,small cementitious materials,and additives are used for backfill materials with poor early compressive strength(ECS),which may greatly affect the mining and backfill cycle,to prepare paste backfi...High-density tailings,small cementitious materials,and additives are used for backfill materials with poor early compressive strength(ECS),which may greatly affect the mining and backfill cycle,to prepare paste backfill materials(PBMs)with a high ECS.The effects and mechanisms of different early strength agents on the property of PBM are investigated.The action mechanism of additives on the properties of PBM is also analyzed through X-ray diffraction,scanning electron microscope,and energy dispersive spectrometry.Results show that the effects of single-component additives 1,3,and 6 are better than those of the other additives,and their optimal dosages are 3wt%,1wt%,and 3wt%,respectively.The optimum multicomponent combinations are 1wt%of additive 1 and 1.5wt%of additive 6.The ECS of the paste with additive 10 increases to a greater extent than that of the other pastes because of the synergistic action of additive 1 with additive 6.The hydration product of Ca(OH)2 is consumed,and more C-S-H gels are generated with the addition of additives to paste.Tailings particles,ettringite crystals,and gels intertwined with one another form a dense net-like structure that fills the pores.This structure can significantly improve the ECS of PBM.展开更多
Tailings consolidation and discharging technology is currently a popular means for disposing tailings in China. In this study, we describe a laboratory investigation of the unclassified tailings slurry from an iron mi...Tailings consolidation and discharging technology is currently a popular means for disposing tailings in China. In this study, we describe a laboratory investigation of the unclassified tailings slurry from an iron mine and analyze the influence of the concentration,amount of consolidation agent, and types of consolidation agent on the pumpability in terms of the slump, slump flow, and bleeding rate of the slurry. The results indicate that an increase in concentration leads to a pronounced decrease in the magnitude of the slump, slump flow,and the bleeding rate. Compared with the consolidation agents P.O42.5 and P.S.A32.5, the new consolidation agent offers substantial advantages in promoting the pumping performance of the slurry. The concentration more strongly affects the slump, slump flow, and the bleeding rate of the slurry than does the amount of the consolidation agent. We also constructed the pumpability interval of the slurry on the basis of the slump and bleeding rate and accordingly determined the proportioning parameters of the slurry with a concentration of 75 wt% to79 wt% and with a consolidation agent concentration of 2 wt%. In addition, we discussed the pumpability mechanism of the slurry.展开更多
AIM To evaluate the role of small bowel capsule endoscopy(SBCE) on the reclassification of colonic inflammatory bowel disease type unclassified(IBDU).METHODS We performed a multicenter, retrospective study including p...AIM To evaluate the role of small bowel capsule endoscopy(SBCE) on the reclassification of colonic inflammatory bowel disease type unclassified(IBDU).METHODS We performed a multicenter, retrospective study including patients with IBDU undergoing SBCE, between 2002 and 2014. SBCE studies were reviewed and the inflammatory activity was evaluated by determining the Lewis score(LS). Inflammatory activity was considered significant and consistent with Crohn's disease(CD) when the LS ≥ 135. The definitive diagnosis during follow-up(minimum 12 mo following SBCE) was based on the combination of clinical, analytical, imaging, endoscopic and histological elements.RESULTS Thirty-six patients were included, 21 females(58%) with mean age at diagnosis of 33 ± 13(15-64) years. The mean follow-up time after the SBCE was 52 ± 41(12-156) mo. The SBCE revealed findings consistent with significant inflammatory activity in the small bowel(LS ≥ 135) in 9 patients(25%); in all of them the diagnosis of CD was confirmed during follow-up. In 27 patients(75%), the SBCE revealed no significant inflammatory activity(LS < 135); among these patients, the diagnosis of Ulcerative Colitis(UC) was established in 16 cases(59.3%), CD in 1 case(3.7%) and 10 patients(37%) maintained a diagnosis of IBDU during follow-up. A LS ≥ 135 at SBCE had a sensitivity = 90%, specificity = 100%, positive predictive value = 100% and negative predictive value = 94% for the diagnosis of CD.CONCLUSION SBCE proved to be fundamental in the reclassification of patients with IBDU. Absence of significant inflammatory activity in the small intestine allowed exclusion of CD in 94% of cases.展开更多
Efficient thickening of tailings is a prerequisite for the metal mine tailings backfill and surface disposal operation.The effective collision of ultrafine tailings particles in suspension with flocculant molecules is...Efficient thickening of tailings is a prerequisite for the metal mine tailings backfill and surface disposal operation.The effective collision of ultrafine tailings particles in suspension with flocculant molecules is essential for flocs aggregates formation and settling.Unreasonable feeding speed and flocculant adding method will lead to the failure of effective dispersion of flocculant and high particle content in thickener overflow.In this work,the effect of turbulence intensity and flocculant adding method on floc size,strength,and movement characteristics are analysed.Aiming to solve the turbidity increased,a pilot-scale continuous thickening test was carried out.Taking a single particle and multiple flocs of full tailings as the research object,the particle iterative settlement model of flocs was established.The influence of turbulence intensity on collision effect is studied by tracking and simulating particle trajectory.The results show that in the process of single particle settlement,chaos appears in the iterative process owing to particle adhesion which caused by micro action.When the turbulence intensity is 25.99%,the maximum particle size of tailings floc is 6.21 mm and the maximum sedimentation rate is 5.284 cm·s^(−1).The tailings floc presents a multi-scale structure of particle-force chain system when hindered settling,and the interweaving of strong and weak force chains constitutes the topological structure of particles.The results are applied to a thicker in plant,the flocculant addition mode and feed rate are optimized,and the flocs settling speed and overflow clarity are improved.展开更多
Introduction: Unclassified inflammatory rheumatism is persistent inflammatory arthralgias with or without synovitis without sufficient classification criteria for an inflammatory rheumatism or a well-defined connectiv...Introduction: Unclassified inflammatory rheumatism is persistent inflammatory arthralgias with or without synovitis without sufficient classification criteria for an inflammatory rheumatism or a well-defined connective disease. Their outcome is variable and has been little studied in Africa. We report the epidemiological, paraclinical and evolutionary characteristics of seven cases of indeterminate polyarthritis. Material and Method: From January 2012 to May 2021, we selected all the files of patients followed up for unclassified inflammatory rheumatism and in whom a precise diagnosis was retained during the course of the disease. The diagnosis of unclassified inflammatory rheumatism was retained after biological, immunological and radiological explorations without specificities. Our study took place in the Internal Medicine Department of Aristide Le Dantec Hospital (HALD). Results: Seven cases out of 274 consulted were collected. They consisted of seven women with an average age of 39 years at the time of the first consultation (extremes: 19 and 67 years). All seven patients presented with inflammatory polyarthralgia or non-deforming, non-erosive peripheral polyarthritis, without extra-articular manifestations. A biological inflammatory syndrome was present in all seven patients. Autoantibodies (rheumatoid factor, ANA, anti-ENA and ACPA) were negative in all patients. The first-line treatments in all seven cases were hydroxychloroquine (200 - 400 mg/day) and prednisone (5 - 10 mg/day). Methotrexate was added in 3 cases. During follow-up, 2 cases progressed to Polyarthritis Rheumatoid (PR) after 3 and 4 years. Two cases progressed to Sjögren’s syndrome after 4 and 5 years. Two patients progressed to systemic scleroderma after 5 and 8 years. One patient progressed to lupus after 5 years. Conclusion: Regular follow-up is essential in IAN. It allows the early diagnosis of IJR or a well-differentiated connective tissue disease and ensures adequate management, especially early.展开更多
Objective:Inflammatory bowel diseases (IBDs) are idiopathic,chronic,and inflammatory intestinal disorders.The two main types,ulcerative colitis (UC) and Crohn's disease (CD),sometimes mimic each other and are not ...Objective:Inflammatory bowel diseases (IBDs) are idiopathic,chronic,and inflammatory intestinal disorders.The two main types,ulcerative colitis (UC) and Crohn's disease (CD),sometimes mimic each other and are not readily distinguishable.The purpose of this study was to present a series of hospitalized cases,which could not initially be classified as a subtype of IBD,and to try to note roles of the terms indeterminate colitis (IC) and inflammatory bowel disease unclassified (IBDU) when such a dilemma arises.Methods:Medical records of 477 patients hospitalized due to IBD,during the period of January 2002 to April 2009,were retrospectively studied in the present paper.All available previous biopsies from endoscopies of these patients were reanalyzed.Results:Twenty-seven of 477 IBD patients (5.7%) had been initially diagnosed as having IBDU.Of them,23 received colonoscopy and histological examinations in our hospital.A total of 90% (9/10) and 66.7% (4/6) of patients,respectively,had a positive finding via wireless capsule endoscopy (CE) and double-balloon enteroscopy (DBE).The barium-swallow or small bowel follow-through (SBFT) was performed on 11 patients.Positive changes were observed under computer tomographic (CT) scanning in 89.5% (17/19) of patients.Reasonable treatment strategies were employed for all patients.Conclusions:Our data indicate that IBDU accounts for 5.7% of initial diagnoses of IBD.The definition of IBDU is valuable in clinical practice.For those who had no clear clinical,endoscopic,histological,or other features affording a diagnosis of either UC or CD,IBDU could be used parenthetically.展开更多
Primary intraosseous lymphoma is rare and there are few case reports manifesting with a mass in the mandible. Thus, we retrospectively reviewed and analyzed the clinical characteristics, treatment, and outcome of extr...Primary intraosseous lymphoma is rare and there are few case reports manifesting with a mass in the mandible. Thus, we retrospectively reviewed and analyzed the clinical characteristics, treatment, and outcome of extranodal non-Hodgkin’s lymphoma (NHL) with initial mandibular symptoms in our department. At initial treatment of dental clinics, dentists had diagnosed as dental or gingival diseases and had performed dental treatment. Neurological disorder to involvement of the inferior alveolar nerve was present in 80.0% of our cases. On dental or panoramic radiography a specific radiolucent lesion in the mandible was not detected, except for dental lesions. On CT, NHL of the mandible region has no widening and no clear destruction but a slit-like the cortex bone destruction pattern with keeping in shape of the mandibular body (62.5% of CT-examined cases), and extraosseous soft tissue mass are clearer on MRI (100.0% of MRI-examined cases). Histopathologically, 80.0% of our cases were diagnosed as diffuse large B cell lymphoma (DLBCL). One case as B-cell lymphoblastic lymphoma and one case as B-cell lymphoma unclassifiable with features intermediate between DLBCL and Burkitt lymphoma were Stage IV (Ann Arbor staging system) and had poor prognosis. The disease-specific survival rate was 77.8% at 5 years. If unexplained non-specific symptoms such as swelling of the jaw, pain, neurological disorder of the inferior alveolar nerve, tooth mobility are observed, oral surgeons and dentists should not perform dental treatments. CT and MRI show disease specific appearance to be able to give a definitive diasnosis as NHL. PET/CT is useful for scaninng of whole body. A deep bone biopsy is preferred for suspected malignant lymphoma.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(No.51834001)the Beijing Municipal Natural Science Foundation(No.2204087).
文摘High-density tailings,small cementitious materials,and additives are used for backfill materials with poor early compressive strength(ECS),which may greatly affect the mining and backfill cycle,to prepare paste backfill materials(PBMs)with a high ECS.The effects and mechanisms of different early strength agents on the property of PBM are investigated.The action mechanism of additives on the properties of PBM is also analyzed through X-ray diffraction,scanning electron microscope,and energy dispersive spectrometry.Results show that the effects of single-component additives 1,3,and 6 are better than those of the other additives,and their optimal dosages are 3wt%,1wt%,and 3wt%,respectively.The optimum multicomponent combinations are 1wt%of additive 1 and 1.5wt%of additive 6.The ECS of the paste with additive 10 increases to a greater extent than that of the other pastes because of the synergistic action of additive 1 with additive 6.The hydration product of Ca(OH)2 is consumed,and more C-S-H gels are generated with the addition of additives to paste.Tailings particles,ettringite crystals,and gels intertwined with one another form a dense net-like structure that fills the pores.This structure can significantly improve the ECS of PBM.
基金financially supported by the Fundamental Research Funds for the Central Universities of China (No. FRF-TP-16-073A1)the State Key Research Development Program of China (Nos. 2017YFC0804103 and 2016YFC0600801)the National Key Basic Research Program of China (973 Program) (No. 2015CB060200)
文摘Tailings consolidation and discharging technology is currently a popular means for disposing tailings in China. In this study, we describe a laboratory investigation of the unclassified tailings slurry from an iron mine and analyze the influence of the concentration,amount of consolidation agent, and types of consolidation agent on the pumpability in terms of the slump, slump flow, and bleeding rate of the slurry. The results indicate that an increase in concentration leads to a pronounced decrease in the magnitude of the slump, slump flow,and the bleeding rate. Compared with the consolidation agents P.O42.5 and P.S.A32.5, the new consolidation agent offers substantial advantages in promoting the pumping performance of the slurry. The concentration more strongly affects the slump, slump flow, and the bleeding rate of the slurry than does the amount of the consolidation agent. We also constructed the pumpability interval of the slurry on the basis of the slump and bleeding rate and accordingly determined the proportioning parameters of the slurry with a concentration of 75 wt% to79 wt% and with a consolidation agent concentration of 2 wt%. In addition, we discussed the pumpability mechanism of the slurry.
文摘AIM To evaluate the role of small bowel capsule endoscopy(SBCE) on the reclassification of colonic inflammatory bowel disease type unclassified(IBDU).METHODS We performed a multicenter, retrospective study including patients with IBDU undergoing SBCE, between 2002 and 2014. SBCE studies were reviewed and the inflammatory activity was evaluated by determining the Lewis score(LS). Inflammatory activity was considered significant and consistent with Crohn's disease(CD) when the LS ≥ 135. The definitive diagnosis during follow-up(minimum 12 mo following SBCE) was based on the combination of clinical, analytical, imaging, endoscopic and histological elements.RESULTS Thirty-six patients were included, 21 females(58%) with mean age at diagnosis of 33 ± 13(15-64) years. The mean follow-up time after the SBCE was 52 ± 41(12-156) mo. The SBCE revealed findings consistent with significant inflammatory activity in the small bowel(LS ≥ 135) in 9 patients(25%); in all of them the diagnosis of CD was confirmed during follow-up. In 27 patients(75%), the SBCE revealed no significant inflammatory activity(LS < 135); among these patients, the diagnosis of Ulcerative Colitis(UC) was established in 16 cases(59.3%), CD in 1 case(3.7%) and 10 patients(37%) maintained a diagnosis of IBDU during follow-up. A LS ≥ 135 at SBCE had a sensitivity = 90%, specificity = 100%, positive predictive value = 100% and negative predictive value = 94% for the diagnosis of CD.CONCLUSION SBCE proved to be fundamental in the reclassification of patients with IBDU. Absence of significant inflammatory activity in the small intestine allowed exclusion of CD in 94% of cases.
基金funded by the National Natural Science Foundation of China (No. 51834001)
文摘Efficient thickening of tailings is a prerequisite for the metal mine tailings backfill and surface disposal operation.The effective collision of ultrafine tailings particles in suspension with flocculant molecules is essential for flocs aggregates formation and settling.Unreasonable feeding speed and flocculant adding method will lead to the failure of effective dispersion of flocculant and high particle content in thickener overflow.In this work,the effect of turbulence intensity and flocculant adding method on floc size,strength,and movement characteristics are analysed.Aiming to solve the turbidity increased,a pilot-scale continuous thickening test was carried out.Taking a single particle and multiple flocs of full tailings as the research object,the particle iterative settlement model of flocs was established.The influence of turbulence intensity on collision effect is studied by tracking and simulating particle trajectory.The results show that in the process of single particle settlement,chaos appears in the iterative process owing to particle adhesion which caused by micro action.When the turbulence intensity is 25.99%,the maximum particle size of tailings floc is 6.21 mm and the maximum sedimentation rate is 5.284 cm·s^(−1).The tailings floc presents a multi-scale structure of particle-force chain system when hindered settling,and the interweaving of strong and weak force chains constitutes the topological structure of particles.The results are applied to a thicker in plant,the flocculant addition mode and feed rate are optimized,and the flocs settling speed and overflow clarity are improved.
文摘Introduction: Unclassified inflammatory rheumatism is persistent inflammatory arthralgias with or without synovitis without sufficient classification criteria for an inflammatory rheumatism or a well-defined connective disease. Their outcome is variable and has been little studied in Africa. We report the epidemiological, paraclinical and evolutionary characteristics of seven cases of indeterminate polyarthritis. Material and Method: From January 2012 to May 2021, we selected all the files of patients followed up for unclassified inflammatory rheumatism and in whom a precise diagnosis was retained during the course of the disease. The diagnosis of unclassified inflammatory rheumatism was retained after biological, immunological and radiological explorations without specificities. Our study took place in the Internal Medicine Department of Aristide Le Dantec Hospital (HALD). Results: Seven cases out of 274 consulted were collected. They consisted of seven women with an average age of 39 years at the time of the first consultation (extremes: 19 and 67 years). All seven patients presented with inflammatory polyarthralgia or non-deforming, non-erosive peripheral polyarthritis, without extra-articular manifestations. A biological inflammatory syndrome was present in all seven patients. Autoantibodies (rheumatoid factor, ANA, anti-ENA and ACPA) were negative in all patients. The first-line treatments in all seven cases were hydroxychloroquine (200 - 400 mg/day) and prednisone (5 - 10 mg/day). Methotrexate was added in 3 cases. During follow-up, 2 cases progressed to Polyarthritis Rheumatoid (PR) after 3 and 4 years. Two cases progressed to Sjögren’s syndrome after 4 and 5 years. Two patients progressed to systemic scleroderma after 5 and 8 years. One patient progressed to lupus after 5 years. Conclusion: Regular follow-up is essential in IAN. It allows the early diagnosis of IJR or a well-differentiated connective tissue disease and ensures adequate management, especially early.
文摘Objective:Inflammatory bowel diseases (IBDs) are idiopathic,chronic,and inflammatory intestinal disorders.The two main types,ulcerative colitis (UC) and Crohn's disease (CD),sometimes mimic each other and are not readily distinguishable.The purpose of this study was to present a series of hospitalized cases,which could not initially be classified as a subtype of IBD,and to try to note roles of the terms indeterminate colitis (IC) and inflammatory bowel disease unclassified (IBDU) when such a dilemma arises.Methods:Medical records of 477 patients hospitalized due to IBD,during the period of January 2002 to April 2009,were retrospectively studied in the present paper.All available previous biopsies from endoscopies of these patients were reanalyzed.Results:Twenty-seven of 477 IBD patients (5.7%) had been initially diagnosed as having IBDU.Of them,23 received colonoscopy and histological examinations in our hospital.A total of 90% (9/10) and 66.7% (4/6) of patients,respectively,had a positive finding via wireless capsule endoscopy (CE) and double-balloon enteroscopy (DBE).The barium-swallow or small bowel follow-through (SBFT) was performed on 11 patients.Positive changes were observed under computer tomographic (CT) scanning in 89.5% (17/19) of patients.Reasonable treatment strategies were employed for all patients.Conclusions:Our data indicate that IBDU accounts for 5.7% of initial diagnoses of IBD.The definition of IBDU is valuable in clinical practice.For those who had no clear clinical,endoscopic,histological,or other features affording a diagnosis of either UC or CD,IBDU could be used parenthetically.
文摘Primary intraosseous lymphoma is rare and there are few case reports manifesting with a mass in the mandible. Thus, we retrospectively reviewed and analyzed the clinical characteristics, treatment, and outcome of extranodal non-Hodgkin’s lymphoma (NHL) with initial mandibular symptoms in our department. At initial treatment of dental clinics, dentists had diagnosed as dental or gingival diseases and had performed dental treatment. Neurological disorder to involvement of the inferior alveolar nerve was present in 80.0% of our cases. On dental or panoramic radiography a specific radiolucent lesion in the mandible was not detected, except for dental lesions. On CT, NHL of the mandible region has no widening and no clear destruction but a slit-like the cortex bone destruction pattern with keeping in shape of the mandibular body (62.5% of CT-examined cases), and extraosseous soft tissue mass are clearer on MRI (100.0% of MRI-examined cases). Histopathologically, 80.0% of our cases were diagnosed as diffuse large B cell lymphoma (DLBCL). One case as B-cell lymphoblastic lymphoma and one case as B-cell lymphoma unclassifiable with features intermediate between DLBCL and Burkitt lymphoma were Stage IV (Ann Arbor staging system) and had poor prognosis. The disease-specific survival rate was 77.8% at 5 years. If unexplained non-specific symptoms such as swelling of the jaw, pain, neurological disorder of the inferior alveolar nerve, tooth mobility are observed, oral surgeons and dentists should not perform dental treatments. CT and MRI show disease specific appearance to be able to give a definitive diasnosis as NHL. PET/CT is useful for scaninng of whole body. A deep bone biopsy is preferred for suspected malignant lymphoma.
