Prediction on hot deformation behavior of spray-formed 7055 aluminum alloy via phenomenological models

Hot compression tests in the temperature range of 340-450 ℃ and strain rate range of 0.001-1 s^-1 of spray-formed 7055 aluminum alloy were carried out to study its hot deformation behavior. Three phenomenological models including Johnson-Cook, modified Fields-Backofen and Arrhenius-type were introduced to predict the flow stresses during the compression process. And then, a comparative predictability of the phenomenological models was estimated in terms of the relative errors, correlation coefficient（R）, and average absolute relative error（AARE）. The results indicate that Johnson-Cook model and modified Fields-Backofen model cannot well predict the hot deformation behavior due to the large deviation in the process of line regression fitting. Arrhenius-type model obtains the best fit through combining the effect of strain rate and temperature.

Microstructure and mechanical properties of Al−Mg−Si alloy U-shaped profile

To get a full understanding of hot extrusion,solid solution treatment and aging process on the Al−0.56Mg−0.63Si alloy,the microstructure and mechanical properties of a U-shaped profile were studied through optical microscopy,scanning electrical microscopy,transmission electrical microscopy,hardness,and tensile tests.The coarse equiaxed grains existed near the profile edge as a result of the dynamic recrystallization nucleation and exceeding growth during hot extrusion.The fibrous deformed and sub-structured grains located between the two coarse grain layers,due to the occurrence of work-hardening and dynamic recovery.Perpendicular needle β′′precipitates were distributed inside the grain,and obvious precipitates-free zone appeared after aging treatment.The tensile strength,yield strength and elongation of the aged Al−Mg−Si alloy U-shaped profile were no less than 279.4 MPa,258.6 MPa,and 21.6%,respectively.The fracture morphology showed dimple rupture characteristics.The precipitates and grain boundaries played key role in the strengthening contribution.

Value of eosinophil count in bronchoalveolar lavage fluid for diagnosis of allergic bronchopulmonary aspergillosis: A case report

BACKGROUND An immediate hypersensitive immune response to Aspergillus fumigatus antigens is one of the main characteristic features of allergic bronchopulmonary aspergillosis(ABPA).As ABPA is an allergic respiratory disease,immunoglobulin E and peripheral-blood eosinophilia have been used as diagnostic indicators.However,eosinophilia in bronchoalveolar lavage fluid(BALF)has not been considered in the diagnostic criteria for ABPA.CASE SUMMARY We present a case of ABPA in which the eosinophil count in peripheral blood was not increased,whereas the eosinophil percentage in BALF reached 60%.After antifungal and hormone therapy,imaging revealed very good resolution of lung infiltration.CONCLUSION The value of the eosinophil count in BALF for the diagnosis of ABPA is worthy of the clinician's attention,especially when the patient’s clinical features lack specificity and the diagnostic parameters are negative.

Pulmonary Cladosporium infection coexisting with subcutaneous Corynespora cassiicola infection in a patient:A case report

BACKGROUND Cladosporium and Corynespora cassiicola(C.cassiicola)infections rarely occur in humans.Mutations in human caspase recruitment domain protein 9(CARD9)are reported to be associated with fungal diseases.Pulmonary Cladosporium infection coexisting with subcutaneous C.cassiicola infection in a patient with a CARD9 mutation has not been reported in the literature.CASE SUMMARY A 68-year-old male patient was hospitalized for hypertrophic erythema and deep ulcers on the left upper extremity.He was diagnosed with pneumonia caused by Cladosporium,as identified through bronchoalveolar lavage fluid analysis,and deep dermatophytosis caused by C.cassiicola,as identified through morphological characteristics of the wound secretion culture.He underwent antifungal therapy(voriconazole)and recovered successfully.He carried two mutations in CARD9(chr9:139266425 and chr9:139262240)and was therefore susceptible to fungal infections.CONCLUSION This case study is the first to report the coexistence of pulmonary Cladosporium infection and subcutaneous C.cassiicola infection in a patient with CARD9 mutation.Our findings will be helpful in enriching the phenotypic spectrum of fungal infections underlying CARD9 deficiency.

Cryptococcal antigen testing of lung tissue homogenate improves pulmonary cryptococcosis diagnosis:Two case reports

BACKGROUND Pulmonary cryptococcosis(PC)is an opportunistic infectious disease of the respiratory system.Lung tissue biopsies,culture of respiratory samples(e.g.,sputum,lung tissue,pleural fluid,and bronchoalveolar lavage fluid),and cryptococcal antigen(CrAg)testing are helpful for a definitive diagnosis.However,these tests are sometimes falsely negative.PC is often misdiagnosed or underdiagnosed owing to the absence of obvert symptoms,poor imaging specificity,and false-negative laboratory tests.CASE SUMMARY We report two female patients who underwent computed tomography-guided percutaneous needle pulmonary biopsy of a lung nodule for a confirmed diagnosis.In both patients,the CrAg test on the lung biopsy tissue homogenate was positive,while the serum CrAg test was negative.Combined with the lung tissue pathology,we made the diagnosis of PC.Antifungal therapy was effective in both patients.CONCLUSION Given the findings of our cases and the literature review,lung tissue homogenate CrAg testing can be helpful in improving the diagnosis of PC.