High Speed Forming of the Light-Weight Wrought Alloys

The deformation and fracture behaviour of the Al-alloy AA7075, Mg-alloy AZ80, and Tialloy Ti-6Al-4V were investigated in quasi-static and dynamic uniaxial compression and tension tests at strain rates in the range of 0.001 s^(-1) ≤ ε̇ ≤ 5000 s^(-1) and temperatures between 20°C and 500°C. Shear tests with hat shaped specimens of AZ80 were carried out by quasi-static and dynamic loading in the shear rate range of 0.01s^(-1) ≤ γ̇ ≤ 116000s^(-1) at a temperature of 20°C. For strain rates of ε̇ ≤ 10 s^(-1), the tests were carried out using a computer numerical controlled hydraulic testing machine. High strain rate experiments with ε̇ ≥ 1000 s^(-1) were performed on a Split Hopkinson Pressure Bar. Using the experimentally determined flow curves, the effect of strain rate and temperature on the compressive deformation at fracture was determined, showing that the forces required for forming as well as the limits of the possible deformation are controlled by strain rate und temperature. Under dynamic loading, both AA7075 and AZ80 show an increase of the deformation degree at fracture with increasing strain rate, whereas the Ti-6Al-4V shows a decrease of it. The investigated mechanical material behaviour (strain hardening, strain rate sensitivity, and thermal softening) and metallographic investigations of the deformed specimens in dynamic compression tests allow an explanation for character, formation, and evolution of damage in the deformed material. Constitutive material laws, whose parameters are determined from the experimental data, can be applied to describe the influence of strain rate and temperature on the mechanical material behaviour in compression, tension and shear tests. These material laws are to be implemented into the FE simulation, in order to determine the local state of stress and strain at time of the fracture. Through combination of experiment and simulation, a failure criterion for ductile fracture could be determined for AA7075 under quasi-static and dynamic tensile loading

The Anticancer Effect of Rhubarb Officinale Fraction and Sorafenib Against Chemically Induced Hepatocellular Carcinoma in Rats

Background: Hepatocellular carcinoma (HCC), the major primary malignant tumour of the liver, represents a complex and fatal malignancy driven primarily by oxidative stress and inflammation. Objectives: The aim of this study was to investigate the potential anticancer properties of four Anthraquinones (Aloe-emodin, Emodin, Chysophanol, and Physcion) isolated from the rhizome of Rhubarb and compare between the effect of sorafenib and Rhubarb Officinale fraction on DEN and carbon tetrachloride (CCl4) -   induced hepatocellular carcinoma in rats. Material and methods: The rats were divided into 5 groups (n=12/group normal control, diethylnitrosamine DEN+ carbon tetrachloride CCL4, HCC rats +ANTH(Anthraquinones), HCC rats +SOR(Sorafenib) and HCC rats +mix of ANTH+SOR. Results: Rats in HCC group showed most deteriorated effect in form of increased mortality, liver cancer marker (lipid peroxidation biomarker MDA, inflammation –related genes (TNFa, ILIB, NFKB, TGFB1) and metastasis-related genes (MMP9). Liver tissues of HCC group also exhibited lower level of TIMPI and antioxidant activity (catalase (CAT). All these deleterious effects induced by DEN were reversed after administration of ANTH and SOR with best improvement for the combined group (ANTH+SOR). Conclusions: These findings reveal a better therapeutic effect for ANTH when given with SOR and we attribute this beneficial effect, at least in part, to triggering antioxidant activity, inflammation and metastasis in HCC. Therefore, combined treatment with ANTH and SOR is recommended to enhance the therapeutic potential against HCC

Death associated protein kinase-1 gene methylation pattern in some leukemic patients attending Zagazig University hospitals: is it a clue?

Background: Leukemia is a type of cancer arising from white blood cells (WBCs) and resulting from malignant transformation of different types of white blood cell precursors. The objective was to study the DAPK-1 gene methylation pattern in leukemic patients and to through some light on its possible role as a risk factor for leukemia.Methods: Forty-one patients diagnosed as leukemic patients and 41 age-matched healthy unrelated volunteers taken as a control group. The analysis of aberrant promoter DAPK1 gene methylation was done by specific polymerase chain reaction.Results: The results of the present study showed that there was a significant association of methylated DAPK-1 promoter area among leukemic group than in control group Chi-square (X2) was 21.98, or value patients was 10.46 and there was a significant association when compared with the control group (p <0.001). And there was no significant association when compared according to gender Chi-square (X2) was 0.43 and (p=0.51). Our results revealed in the AML group DAPK-1 promoter area were methylated with percentage of 73.9%. or value for AML patients was 13.76 and there was a significant association when compared with the control group (p <0.001), in the ALL group 4 patients had methylated DAPK-1 promoter area with percentage of 57.1% or value for all patients was 6.47 and there was a significant association when compared with the control group (p=0.03) and in the CLL group 7 patients had methylated DAPK-1 promoter area with percentage of 63.6%. OR value for CCL patients was 8.5 and there was a significant association when compared with the control group (p=0.004). On the contrary, we didn’t observe any significant associations between DAPK-1 promoter area methylation and the type of leukemia (p = 0.65).Conclusions: These results suggested that DAPK1 promoter methylation might play a significant role in the pathogenesis of different types of leukemia. And the DAPK1 promoter methylation has a predictive value in the prediction of leukemia occurrence.

French women and Nazi concentration camps: A study of the testimonies of French female survivors

This thesis is a study of the experiences of French women deported to Nazi concentration camps during World War Two, conducted with reference to an extensive corpus of published and archival autobiographical testimonies written by French female camp survivors. The testimonies of French male survivors and non-French writers are also utilised to a lesser degree as supplementary and comparative sources. The thesis aims to contribute to concentration camp scholarship by configuring a hitherto unrealised comprehensive portrait of the French female body of writing, elucidating how French women depict their camp experience, their responses to the unique challenges of testimonial writing and the gender specificity of this literature. Focusing on those aspects which are most significant within the testimonies of French women, the study demonstrates how social and biological gender specificity shape and particularize the narratives of these women. It also encompasses the pivotal theme of inmate relations, revealing the simultaneous externalization and redefinition of the notion of prisoner privilege which occurs in these writers' portrayal of hierarchical prisoner interaction, as well as the marked emphasis which French female survivors place upon the concepts of solidarity, mutual aid and collective structures. The purely textual level is also examined, detailing both the variety of responses to the issues of testimonial writing manifested by these writers and the cross-narrative authorial conception of the testimony as ultimately problematic. These areas of inquiry combine to yield a portrait of a highly complex testimonial genre, characterized by often unresolved tensions which are reflective of the complex and consistently nuanced nature of the wider camp experience

Ресурсоэффективные системы в управлении и контроле: взгляд в будущее. Ч. 4

В сборнике представлены материалы III Международной конференции школьников, студентов, аспирантов, молодых ученых "Ресурсоэффективные системы в управлении и контроле: взгляд в будущее". Более 500 авторов из 35 вузов, предприятий и научных исследовательских университетов России, ближнего и дальнего Зарубежья представили тезисы своих докладов, в которых рассматриваются актуальные проблемы неразрушающего контроля и технической диагностики, внедрения систем менеджмента, качества образования, управления в современной экономике. Материалы предназначены для специалистов, преподавателей, аспирантов и студентов вузов, а также для всех интересующихся проблемами ресурсоэффективных технологий

Spanish Poplar Biomass as a Precursor for Nanocellulose Extraction

The effect of acidic hydrolysis duration on nanocellulose size, morphology, and proper ties was investigated, which opens up a whole new horizon of versatility in poplar applications. This study aimed to examine Spanish poplar wastes as raw material to extract crystalline nanocellulose (CNC), which substantiates the importance of poplar wastes. Wastes were pulped using 1 L of 10% NaOH (wt./wt.) solution, and bleached several times by NaClO2 ; afterwards, white wastes were subjected to acidic hydrolysis by 60% H2SO4 for either 5, 10, or 15 min. Microcrystalline cellulose (MCC) underwent a similar hydrolysis protocol as poplar as control. TEM, IR, and XRD characterization techniques were performed. Poplar based nanocellulose sized 219 nm length and 69 nm width after 15 min acidic hydrolysis. MCC yielded 122 nm length and 12 nm width crystals after 10 min acidic hydrolysis. Hydrolysis resulted in a drastic change and intense peaks at 3500 and 2900 cm−1 for nanocellulose. Although pre-hydrolysis fiber treatment was not influencial on the crystallinity of poplar, acidic hydrolysis remarkably raised the crystallinity index (CI) by 7–8%. The more hydrolysis duration was prolonged, the size of the resulting crystal (whisker) decreased, and the aspect ratio increased. Hydrolysis was more impactful on MCC than poplar. However, for future work, it seems that longer duration of pulping and bleaching could have significantly removed unwanted components (hemicellulose and lignin), showcased in IR and XRD, and hence smoothened the following hydrolysis.European Union under umbrella of Erasmus+ KA107 PhD Mobility schem

Proučavanje relativističke tvorbe hadrona prema naprijed i unatrag u sudarima 3he i 4he s jezgrama u emulziji na energiji ubrzivača u dubni

The experimental results on 3He- and 4He-emulsion interactions accompanied by relativistic (shower) hadrons flying into the backward (θlab ≤ 90◦ ) hemisphere at 4.5 AGeV/c are presented and analyzed. The dependence of the probabilities of these interactions on the different target sizes, impact parameter and projectile spectator charges is studied. An investigation of average values and multiplicity distributions of these hadrons for the interactions with light and heavy emulsion nuclei has been carried out. In addition, the correlations between the multiplicities of different types of the emitted particles are studied. The data show that backward shower particles are a sensitive target parameter. The values of impact parameters can be used as good indicators for selecting events which occured with light or heavy emulsion nuclei. A comparison with the modified cascade model shows a good performance in describing the data produced in the region having less cascading (i.e. interactions with light nuclei). As for the interactions with heavy nuclei, the model overestimates the experimental data.Predstavljamo eksperimentalne rezultate i analize mjerenja međudjelovanja 3He i 4He u emulziji na 4.5 AGeV/c, u kojima se opažaju relativistički pljuskovi hadrona koji lete unatrag (θlab ≤ 90◦ ). Proučavamo ovisnost vjerojatnosti tih međudjelovanja o veličini jezgre mete, sudarnom parametru i naboju projektila-promatrača. Istražili smo prosječne vrijednosti i raspodjele višestrukosti hadrona za lake i teške jezgre u emulziji. Nadalje, proučavali smo korelacije višestrukosti različitih izlaznih čestica. Podaci pokazuju da su pljuskovi čestica unatrag osjetljiv parametar jezgri mete. Vrijednosti parametara mogu poslužiti kao dobar pokazatelj sudara s lakim odnosno teškim jezgrama. Usporedba s promijenjenim kaskadnim modelom pokazuje dobro slaganje s podacima u kojima je manje kaskada (tj. Manje sudara s lakim jezgrama). Rezultati tog modela za teške jezgre veći su od eksperimentalnih podataka