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This research aims to study the effect of the dosage of anhydrous sodium metasilicate activator on the long-term properties of fly ash-based one-part alkali-activated binders (OPAAB) cured at ambient conditions. Powdered sodium metasilicate activator was utilized in the range of 8–16% by weight of the fly ash in producing the OPAAB. The properties examined are hardened density, compressive strength, flexural strength, water absorption, efflorescence formation, and microstructural analysis. The experimental result revealed that the binders exhibited excellent long-term strength properties. The compressive strength of the OPAAP is well correlated with its hardened density. The pastes were found to exhibit good soundness characteristics over the long-term. The absorption of water decreases with an increase in the activator dosage from 8–12%, and beyond that, the water absorption relatively remains the same. Field emission scanning electron microscope (FESEM) micrograph revealed uniformly formed solid matrices with the micro-crack present were observed in the samples. The larger pore size promotes the crystallization of the resulting hydrate substances (N, C)-A-S-H gel. The initial dissolution of the OPAAP occurred within the first 30 min. At longer age of curing, mixtures with a higher dosage of powdered activator tend to absorb less water. Strength properties beyond 28 days are considered as the long-term strength.  相似文献   
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Background

For several tumor entities, automated treatment planning has improved plan quality and planning efficiency, and may enable adaptive treatment approaches. Whole-pelvic prostate radiotherapy (WPRT) involves large concave target volumes, which present a challenge for volumetric arc therapy (VMAT) optimization. This study evaluates automated VMAT planning for WPRT-VMAT and compares the results with manual expert planning.

Methods

A system for fully automated multi-criterial plan generation was configured for each step of sequential-boost WPRT-VMAT, with final “autoVMAT” plans being automatically calculated by the Monaco treatment planning system (TPS; Elekta AB, Stockholm, Sweden). Configuration was based on manually generated VMAT plans (manualVMAT) of 5 test patients, the planning protocol, and discussions with the treating physician on wishes for plan improvements. AutoVMAT plans were then generated for another 30 evaluation patients and compared to manualVMAT plans. For all 35 patients, manualVMAT plans were optimized by expert planners using the Monaco TPS.

Results

AutoVMAT plans exhibited strongly improved organ sparing and higher conformity compared to manualVMAT. On average, mean doses (Dmean) of bladder and rectum were reduced by 10.7 and 4.5?Gy, respectively, by autoVMAT. Prostate target coverage (V95%) was slightly higher (+0.6%) with manualVMAT. In a blinded scoring session, the radiation oncologist preferred autoVMAT plans to manualVMAT plans for 27/30 patients. All treatment plans were considered clinically acceptable. The workload per patient was reduced by > 70 min.

Conclusion

Automated VMAT planning for complex WPRT dose distributions is feasible and creates treatment plans that are generally dosimetrically superior to manually optimized plans.
  相似文献   
97.
A 67-year-old male presented with anasarca and persistent non-pruritic rash of lower extremities. Physical examination was positive for subcutaneous edema with a non-blanching rash of abdomen and lower extremities. Labs showed leukocytosis, lymphocytosis, anemia and thrombocytopenia. He also had acute kidney injury and high anion gap (AG) metabolic acidosis with elevated lactic acid (11.3 mg/dL). Computerized tomography (CT) of abdomen and pelvis showed hepatosplenomegaly, ascites and abdominal lymphadenopathy. Peripheral blood (PB) smear showed blastiod appearing lymphocytes. He was started on bicarbonate infusion due to persistent lactic acidosis (LA), however showed no significant improvement. He was started on IV dexamethasone on 3rd day of hospitalization based on preliminary result of peripheral picture which led to some improvement in LA. Following the confirmation of mantle cell lymphoma (MCL) on bone marrow (BM) biopsy and immunophenotyping, the patient started receiving VR-CAP regimen (bortezomib, rituximab, cyclophosphamide, doxorubicin, and prednisone) which led to significant improvement in LA and leukocytosis. After discharge, he received further chemotherapy with resolution of the LA and normalization of blood counts. Restaging tests confirmed a complete remission with resolution of the skin rash, resolution of the pathological lymphadenopathy and hepatosplenomegaly on imaging, and absence of lymphoma on a repeat BM biopsy.  相似文献   
98.
The present hospital based, group matched case control study was carried out at Gynaecology clinic, Govt. Medical College Hospital, Nagpur, to study risk factors for cancer cervix and investigate their independent and interactive role in the outcome of cervical cancer. The study included 230 cases of cancer cervix and equal number of controls, group matched for age. Univariate analysis included 17 hypothesised risk factors for cancer cervix and identified significance of 10 risk factors. However multiple logistic regression (MLR) analysis recognised and confirmed the significance of illiteracy, poor genital hygiene, long duration of married life, multiparity and early menarche in the ultimate outcome of cancer cervix. Estimates of Attributable Risk Proportions (ARP) and Population Attributable Risk Proportion (PARP) endorsed the etiological and preventable role of these risk factors, respectively. Considering the public health impact of elimination of these risk factors on the cancer cervix problem in this population, development of a preventive strategy based on these risk factors would be an appropriate step towards curtailment of this "Biggest Scourge of womankind".  相似文献   
99.
During a two years period, 16 cases having cervical lymphadenopathy presenting as prolonged fever were studied in Abbassia fever hospital, Cairo, Egypt. Patients were subjected to careful history, thorough clinical examination, complete blood picture, tuberculin test, chest x-ray, Monospot test, indirect fluorescent antibody test for toxoplasmosis, detection of cytomegalovirus antibodies and lymph node biopsy with histopathological examination. Ten within normal subjects were taken as controls. The patients were grouped on histopathological basis into 5 groups: (1) One (6%) of the cases was non-specific lymphadenitis diagnosed by clinical examination of the scalp and leucocytosis with polymorphonuclear predominance. (2) Reactive lymphadenitis included 6 (38%) of the cases. Infectious mononucleosis cases were diagnosed by clinical triad of fever, pharyngitis and cervical lymphadenopathy, relative lymphocytosis, monocytosis and positive monospot test. Cytomegalovirus case was diagnosed by lymphocytosis, monocytosis and negative monospot test. Toxoplasmosis cases were diagnosed by monocytosis, negative tuberculin test and positive indirect fluorescent antibody test. (3) Granulomatous lymphadenitis comprised 6 (3%) of the cases. Tuberculous cases were diagnosed by high ESR and highly positive tuberculin test. Sarcoidosis cases were diagnosed by negative tuberculin test and presence of hilar lymphadenopathy. (4) Non-Hodgkin lymphoma case (6%) was diagnosed by clinical deterioration and total lymph node biopsy. 15) Systemic infections were diagnosed by clinical examination, blood culture for salmonellae and brucellae, Widal and Brucella agglutination tests. It is concluded from this study that screening tests are important aids in the diagnosis of cases of cervical lymphadenopathy presenting by prolonged fever especially if lymph node biopsy and histopathological examination are not available or contraindicated. Tub  相似文献   
100.
Living donor liver transplantation has shorter cold ischemia time, less preservative volume, and lower metabolic load compared to transplantation from deceased donors. We investigated the impact of rinsing the graft contents into the systemic circulation on operative course and postoperative outcomes. Donors had right hepatectomy, and grafts were preserved with cold histidine‐tryptophan‐ketoglutarate solution. On ending portal vein anastomosis, grafts were flushed by patient's portal blood either through incompletely anastomosed hepatic vein (extracorporeal rinse group, EcRg, n = 40) or into systemic circulation (circulatory rinse group, CRg, n = 40). The primary outcome objective was the lowest mean arterial blood pressure within 5 min after portal unclamping as a marker for postreperfusion syndrome (PRS). Secondary objectives included hemodynamics and early graft's and patient's outcomes. Within 5 min postreperfusion, mean arterial blood pressure was significantly lower in the CRg compared to the EcRg, yet this was clinically insignificant. Postoperative graft functions, early biliary and vascular complications, and three‐month survival were comparable in both groups. Rinsing the graft into the circulation increased the incidence of PRS without significant impact on early graft or patient outcome in relatively healthy recipients.  相似文献   
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