bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prediction of notch sensitivity effects in fatigue and in environmentally assisted cracking
Authors: de Castro J. T. P. , Landim R. V. , Leite J. C. C. , Meggiolaro M. A. 
Published: March 2014

AbstractSemi‐empirical notch sensitivity factorsqhave been used for a long time to quantify notch effects in fatigue design. Recently, this old concept has been mechanically modelled using sound stress analysis techniques, which properly consider the notch tip stress gradient influence on the fatigue behaviour of mechanically short cracks. This mechanical model properly calculatesqvalues from the basic fatigue properties of the material, its fatigue limit and crack propagation threshold, considering all the characteristics of the notch geometry and of the loading, without the need for any adjustable parameter. This model's predictions have been validated by proper tests, and a criterion to accept tolerable short cracks has been proposed based on it. In this work, this criterion is extended to model notch sensitivity effects in environmentally assisted cracking conditions.
Dislocation distributions in monocrystalline nickel‐based superalloys subjected to thermo‐mechanical fatigue with and without hold times
Authors: Sun F. , Zhang J. 
Published: March 2014

ABSTRACTThe characteristics of dislocation configurations under thermo‐mechanical fatigue cycling were investigated in [001] oriented nickel‐based single‐crystal superalloys. Thermo‐mechanical fatigue tests were performed on TMS‐75 (without hold time) and TMS‐82 (with hold time) superalloys. The specimens were subsequently studied by transmission electron microscopy under two‐beam conditions. In TMS‐75 superalloy, cross‐slipping is the main characteristic for the low number of dislocations. In TMS‐82 superalloy, more complex process of dislocation configurations has been demonstrated in detail, involving five stages: after the first stress relaxation, after the first tensile plastic deformation, after the second stress relaxation, after 30 cycles and after rupture. In addition, for TMS‐82 superalloy, there is a reversible movement behaviour of stacking faults that occur in compression and disappear in tension. After rupture, the number of dislocation is related to the hold time. Longer hold time could generate a higher degree of stress relaxation and produce more dislocations with climbing characteristic.
Design and characterization of a biomimetic composite inspired to human bone
Authors: Libonati F. , Colombo C. , Vergani L. 
Published: March 2014

ABSTRACTMany biological materials are generally considered composites, made of relatively weak constituents and with a hierarchical arrangement, resulting in outstanding mechanical properties, difficult to be reached in man‐made materials. An example is human bone, whose hierarchical structure strongly affects its mechanical performance, toughness in particular, by activating different toughening mechanisms occurring at different length scales. At microscale, the principal toughening mechanism occurring in bone is crack deflection. Here, we study the structure of bone and we focus on the role of the microstructure on its fracture behaviour, with the goal of mimicking it in a new composite. We select the main structural features, the osteons, which play a crucial role in leading to crack deflection, and we reproduce them in a synthetic composite. The paper describes the design, manufacturing and characterization of a newly designed composite, whose structure is inspired to the Haversian structure of cortical bone, and that of a classic laminate developed for comparative reasons. We conclude with a critical discussion on the results of the mechanical tests carried out on the new composite and on the comparative laminate, highlighting strengths and shortcomings of the new biomimetic material.
Can ants equal honeybees as effective pollinators of the energy crop Jatropha curcas L. under Mediterranean conditions?
Authors: Samra Shahar , Samocha Yael , Eisikowitch Dan , Vaknin Yiftach 
Published: March 2014

AbstractJatropha curcas L. is the subject of many research and breeding programs concerned with its potential as an oil crop for biodiesel production. Despite an increasing amount of information regarding this relatively new crop, pollination requirements of this plant are largely neglected. The aim of the study was to evaluate the relative significance of ants and honeybees as potential pollinators of J. curcas grown under Mediterranean conditions. Jatropha curcas plants bloomed throughout the summer and fall, peaking twice, in early summer and late fall. During this period, the plants were visited by 70 species of insects representing 45 families from seven orders, with most species rarely being observed. Ants and Honeybees were the most common species, accounting for >95% of all flower visits. The foraging behavior of the honeybees followed the pattern of bloom phenology, especially during the summer, and mostly promoted cross‐pollination. Ants on the other hand, mostly promoted self pollination showing no such correlative behavior, reacting often too late to nectar availability, and were highly susceptible to climatic changes. Pollinator exclusion treatments revealed that during summer, fruit and seed sets, as well as seed size and oil and protein contents, were relatively similar for ant and bee‐pollinated flowers. During fall, however, reproductive success of bee‐pollinated flowers was relatively high (66%), while fruit set of ant‐pollinated flowers was significantly reduced from 71 to 11%. In conclusion, while both groups are equal in their pollination effectiveness in the summer, during the fall the honeybees are almost the sole pollinators of the plant. Based on bloom phenology and pollination activity data, the honeybees are responsible for the pollination of more than 80% of the annual reproductive potential of J. curcas, under Mediterranean conditions.
MARXISM, GENDER AND MEDIATED MEMORIES OF NATIONAL SOCIALISM: THE PARADOXICAL CASE OF CHRISTA WOLF'S KINDHEITSMUSTER (1976)
Authors: Stone Katherine 
Published: March 2014

ABSTRACTThis article explores ambivalences in the representation of women's participation in the Third Reich in Christa Wolf's Kindheitsmuster (1976). Its thematic and aesthetic departure from the GDR's official stance towards National Socialism is well‐noted. As this article demonstrates, however, Wolf's subversive feminine and moral perspective on the Nazi past also relies on an ideal of human interaction, embodied in some of the female protagonists. This leads Wolf to reinstate the idealised gender norms that traditionally define the memory of National Socialism. Her association of women with essential values further clashes with institutional Marxism's emphasis on the historical, and therefore changeable, nature of man, his social relations, and of gendered oppression. This article considers Wolf's paradoxical departure from and reinscription of the state‐sanctioned model of history in light of the Marxist texts that have shaped Wolf's interpretation of fascism, paying particular attention to the place of the Frankfurt School's concept of instrumental reason and J.J. Bachofen's notion of matriarchy in her feminist and historical understanding. An examination of the ambivalent construction of gender and guilt in Kindheitsmuster raises important questions about how gender functions symbolically in the left‐wing texts that came to shape post‐war interpretations of National Socialism in both Germanies.
Effects of long‐acting somatostatin analogues on redox systems in rat lens in experimental diabetes
Authors: Kunjara Sirilaksana , Greenbaum A. Leslie , Sochor Milena , Flyvbjerg Allan , Grønbaek Henning , McLean Patricia 
Published: March 2014

SummaryThe effects of long‐acting somatostatin analogues, angiopeptin (AGP) and Sandostatin (SMS), on the early decline in the lens content of glutathione (GSH), ATP and NADPH and increase in sorbitol were studied in STZ diabetic rats, and comparison was made with the effect of insulin. Three factors prompted this study: (i) the known increase in IGF‐1 in ocular tissue in diabetes and antagonistic effect of somatostatins, (ii) the known effect of IGF‐1 in increasing lens aldose reductase and (iii) the lack of effect of somatostatins on diabetic hyperglycaemia, the latter enabling a differentiation to be made between effects of hyperglycaemia per se and site(s) of IGF‐1/somatostatins. All four metabolites studied showed a significant restoration towards the normal control level after 7 days of treatment with AGP and SMS, and AGP was more effective on levels of GSH and ATP. A significant correlation was found between GSH and ATP across all groups at 7 days treatment. The redox state changes in diabetes include both NADP+/NADPH and NAD+/NADH in the conversion of glucose to sorbitol and via sorbitol dehydrogenase to fructose with a linked decrease in ATP formation via NAD+/NADH regulation of the glycolytic pathway. The interlinked network of change includes the requirement for ATP in the synthesis of GSH. The present study points to possible loci of action of somatostatins in improving metabolic parameters in the diabetic rat lens via effects on aldose reductase and/or glucose transport at GLUT 3.
Lingual ulceration associated with retinoic acid syndrome during treatment of acute promyelocytic leukemia
Authors: Riganti Julia , Caviedes Mariana P. , Torre Ana C. , Maqueda Mariana Guzzi , Piñero Maria C. Baztan , Volonteri Victoria I. , Galimberti Ricardo L. 
Published: March 2014

AbstractBackgroundAll‐trans retinoic acid (ATRA) is routinely associated with chemotherapy for the treatment of acute promyelocytic leukemia (APL). Several reports of scrotal ulceration induced by this agent have been made in the recent years.AimsThe aim of this article was to report the first case of a lingual ulceration associated with retinoic acid syndrome (RAS).Matherials and MethodsWe presented a 32‐year‐old man with a diagnosis of acute promyelocytic leukemia who received treatment with ATRA. He presented with febrile neutropenia and a lingual ulcer that did not respond to antibiotic and antifungal regimens. He developed weight gain, lower limb edema, polyserositis, and acute renal failure. Retinoic acid syndrome syndrome was diagnosed.ResultsAn exhaustive attempt to exclude infectious causes was made performing repeated cultures, histologic examinations, and direct immunofluorescence for HSV. No causative agent was identified. Re‐epithelialization of the ulcer was achieved with ATRA cessation and treatment with systemic steroids.DiscussionAs far as we are concerned, we report the first case of a lingual ulceration associated with RAS.ConclusionIt is important for dermatologists to recognize this cutaneous complication of ATRA as it poses many differential diagnoses in neutropenic patients.
Bloom syndrome
Authors: Arora Harleen , Chacon Anna H. , Choudhary Sonal , McLeod Michael P. , Meshkov Lauren , Nouri Keyvan , Izakovic Jan 
Published: March 2014

AbstractBloom Syndrome (BS, MIM #210900) is an autosomal recessive genetic disorder caused by a mutation in the BLM gene, which codes for the DNA repair enzyme RecQL3 helicase. Without proper DNA repair mechanisms, abnormal DNA exchange takes place between sister chromatids and results in genetic instability that may lead to cancer, especially lymphoma and acute myelogenous leukemia, lower and upper gastrointestinal tract neoplasias, cutaneous tumors, and neoplasias in the genitalia and urinary tract. BS patients are usually of Ashkenazi Jewish descent and exhibit narrow facial features, elongated limbs, and several dermatologic complications including photosensitivity, poikiloderma, and telangiectatic erythema. The most concerning manifestation of BS is multiple malignancies, which require frequent screenings and strict vigilance by the physician. Therefore, distinguishing between BS and other dermatologic syndromes of similar presentation such as Rothmund–Thomson Syndrome, Erythropoietic Protoporphyria, and Cockayne Syndrome is paramount to disease management and to prolonging life. BS can be diagnosed through a variety of DNA sequencing methods, and genetic testing is available for high‐risk populations. This review consolidates several sources on BS sequelae and aims to suggest the importance of differentiating BS from other dermatologic conditions. This paper also elucidates the recently discovered BRAFT and FANCM protein complexes that link BS and Fanconi anemia.
Effects of smoking on human telomerase reverse transcriptase expression in the skin
Authors: Lotfi Ranya A. , El Zawahry Khaled M. , Kamar Zeinab A. , Hashem Zamzam 
Published: March 2014

AbstractBackgroundTelomeres are DNA–protein complexes that cap chromosomal ends, promoting chromosome stability. Telomerase is a ribonucleoprotein complex with a direct telomere protective function. Telomere shortening represents lifetime exposure to oxidative stress and is negatively correlated with age, smoking, and mortality. Smoking increases oxidative DNA modification and thus may influence telomere dynamics and human telomerase reverse transcriptase (hTERT) activity.ObjectivesThis study investigated the effect of smoking on hTERT expression in the skin of smokers and non‐smokers.MethodsA cross‐sectional study in 20 current smokers and 20 non‐smokers was conducted. Three‐mm punch skin biopsies were obtained. Biopsies were examined in routine hematoxylin and eosin staining and immunohistochemistry to investigate expression of hTERT.ResultsAll skin biopsies from smokers and non‐smokers showed cytoplasmic staining in epidermal cells. Sections positive for hTERT expression showed nuclear and some nucleolar staining in cells of the basal and suprabasal layers. In the dermis, hTERT expression was present in some skin appendages. The epidermis of smokers showed positive hTERT in 55% and negative hTERT in 45% of biopsies. The epidermis of non‐smokers showed positive hTERT in 70% and negative hTERT in 30% of biopsies (P > 0.05). Among smokers, 20% showed positive and 80% showed negative hTERT expression in the dermis. Among non‐smokers, 30% showed positive and 70% showed negative hTERT expression in the dermis. A higher mean pack year value was found in subjects with negative rather than positive hTERT expression (P < 0.01). In addition, pack year was inversely correlated with hTERT expression in the epidermis (P < 0.05): as pack year increased, hTERT expression decreased. Mean pack year values were higher in subjects with negative rather than positive hTERT expression in the dermis (P < 0.01).ConclusionsThis research focused on smoking as a lifestyle factor that may alter telomere length and subsequently telomerase kinetics in the skin. Findings showed a higher percentage of negative hTERT in the epidermis and dermis among smokers compared with non‐smokers and a higher percentage of positive hTERT expression among non‐smokers (not significant). The results of this work showed a statistically significant higher mean pack year count among cases with negative rather than positive hTERT expression in the epidermis and dermis. Pack year count was inversely correlated to hTERT scoring in the epidermis (percentage of cells stained) and hTERT expression in the dermis. Thus, smoking may affect telomerase activity in the skin, thereby contributing to skin aging.
Blocking of the ATP sensitive potassium channel ameliorates the	ischaemia‐reperfusion injury in the rat testis
Authors: Shimizu S. , Oikawa R. , Tsounapi P. , Inoue K. , Shimizu T. , Tanaka K. , Martin D. T. , Honda M. , Sejima T. , Tomita S. , Saito M. 
Published: March 2014

SummaryThere is increasing evidence that the effects of administered ATP sensitive potassium (KATP) channel openers or blockers during ischaemia are still controversial in many organs/tissues. Testicular torsion detorsion which causes ischaemia‐reperfusion (IR) injury, cannot be predicted, thus an effective drug should be administered during or after the ischaemia. The aim of this study was to examine whether the administration of KATP channel openers or blockers during ischaemia ameliorates IR injury in the testis. Eight‐week‐old male Sprague–Dawley rats were subjected to 2 h right testicular ischaemia followed by 24 h reperfusion. The selective mitochondrial (mito) KATP channel blocker, 5‐hydroxydecanoate (5‐HD) (40 mg/kg), the non‐selective KATP channel blocker glibenclamide (5 mg/kg), the selective mito KATP channel opener diazoxide (10 mg/kg) and the non‐selective KATP channel opener cromakalim (300 μg/kg) were administered intraperitoneally 15 min prior to the ischaemia or 75 min after the induction of ischaemia. Tissue damage was evaluated by malondialdehyde concentration, myeloperoxidase activity, histological evaluation and TdT‐mediated dUTP nick end labelling assay in the testis. There was a significant increase in oxidative stress, neutrophil infiltration, histological damage and apoptosis in the testicular IR model. A significant reduction in the testicular IR injury was observed with the administration of glibenclamide, but not 5‐HD, diazoxide or cromakalim during ischaemia. The administration of non‐selective KATP channel blocker glibenclamide ameliorated the testicular IR injury. On the other hand, the selective mito KATP channel blocker, 5‐HD and KATP channel openers did not reduce the testicular IR injury. These data suggest that blocking of the membrane KATP channel may have a protective effect during the testicular ischaemia. Glibenclamide could be an effective drug to manage the post‐ischaemic injury caused by the testicular torsion‐detorsion.
Electrical Conductivity of Mullite Ceramics
Authors: Malki Mohammed , Hoo Christopher M. , Mecartney Martha L. , Schneider Hartmut 
Published: March 2014

The electrical conductivity of a lab‐produced homogeneous mullite ceramic sintered at 1625°C for 10 h with low porosity was measured by impedance spectroscopy in the 0.01 Hz to 1MHz frequency range at temperatures between 300°C and 1400°C in air. The electrical conductivity of the mullite ceramic is low at 300°C (≈0.5 × 10−9 Scm−1), typical for a ceramic insulator. Up to ≈ 800°C, the conductivity only slightly increases (≈0.5 × 10−6 Scm−1 at 800°C) corresponding to a relatively low activation energy (0.68eV) of the process. Above ≈ 800°C, the temperature‐dependent increase in the electrical conductivity is higher (≈10−5 Scm−1 at 1400°C), which goes along with a higher activation energy (1.14 eV). The electrical conductivity of the mullite ceramic and its temperature‐dependence are compared with prior studies. The conductivity of polycrystalline mullite is found to lie in‐between those of the strong insulator α‐alumina and the excellent ion conductor Y‐doped zirconia. The electrical conductivity of the mullite ceramic in the low‐temperature field (< ≈800°C) is approximately one order of magnitude higher than that of the mullite single crystals. This difference is essentially attributed to electronic grain‐boundary conductivity in the polycrystalline ceramic material. The electronic grain‐boundary conductivity may be triggered by defects at grain boundaries. At high temperatures, above ≈ 800°C, and up to 1400°C gradually increasing ionic oxygen conductivity dominates.
Normal‐Relaxor‐Diffuse Ferroelectric Phase Transition and Electrical Properties of Bi(Mg1/2Ti1/2)3–PbZrO3–PbTiO3 Solid Solution Ceramics Near the Morphotropic Phase Boundary
Authors: Yi Haifeng , Zuo Ruzhong 
Published: March 2014

Perovskite‐type xBi(Mg1/2Ti1/2)O3–(0.56 − x)PbZrO3–0.44PbTiO3 (xBMT–PZ–PT) ternary solid solution ceramics were synthesized via a conventional solid‐state reaction method. The phase transition behaviors, dielectric, ferroelectric, and piezoelectric properties were investigated as a function of the BMT content. The X‐ray diffraction analysis showed that the tetragonality of xBMT–PZ–PT was enhanced with increasing the BMT content, and a morphotropic phase boundary (MPB) between rhombohedral and tetragonal phases was identified approximately in the composition of x = 0.08. In addition, the dielectric diffuseness and frequency dispersion behavior were induced with the addition of BMT and a normal‐relaxor‐diffuse ferroelectric transformation was observed from the PZ‐rich side to the BMT‐rich side. The electrical properties of xBMT–PZ–PT ceramics exhibit obviously compositional dependence. The x = 0.08 composition not only possessed the optimum properties with εT33/ε0 = 1450, Qm = 69, d33 = 390 pC/N, kp = 0.46, Pr = 30 μC/cm2, Ec = 1.4 kV/mm, Tc = 325°C, and a strain of 0.174% (d33* = 436 pm/V) under an electric field of 4 kV/mm as a result of the coexistence of two ferroelectric phases near the MPB, but also owned a good thermal‐depolarization behavior with a d33 value of >315 pC/N up to 290°C and a frequency‐insensitive strain behavior.
Confocal analysis of the exopolysaccharide matrix ofCandida albicansbiofilms
Authors: Gonçalves Letícia M. , Del Bel Cury Altair A. , de Vasconcellos Andréa A. , Cury Jaime A. , da Silva Wander J. 
Published: March 2014

AbstractAimConfocal laser‐scanning microscopy (CLSM) was carried out to investigate the exopolysaccharide matrix ofCandida albicans(C. albicans) biofilms developed on denture material under dietary carbohydrate exposure.MethodsBiofilms were developed on poly(methyl methacrylate) discs in culture media without (control) or with supplementation by glucose or sucrose for 72 h. For theCLSManalysis, biofilms were labeled with concanavalin A (ConA) during its development. Afterwards, biofilms were also labeled withSYTO‐9. To confirm the results, the matrix was investigated by the phenol‐sulfuric method. Data were analyzed byanova, followed by Tukey's test, with the level of significance set at 5%.ResultsThe use of ConA during biofilm development provided effective labeling of the exopolysaccharide matrix. The exposure to sucrose resulted in biofilms with the highest exopolysaccharide matrix biovolume (P < 0.05). The characterization obtained byCLSMwas confirmed by the phenol‐sulfuric method.ConclusionConfocal laser‐scanning microscopy was found to be an effective tool for investigating the exopolysaccharide matrix ofC. albicansbiofilms, and exposure to sucrose resulted in increased matrix production.
Can Efficiency Improvements Reduce Resource Consumption?
Authors: Dahmus Jeffrey B. 
Published: March 2014

SummaryThis work explores the historical effectiveness of efficiency improvements in reducing humankind's consumption of energy resources. Ten activities are analyzed, including pig iron production, aluminum production, nitrogen fertilizer production, electricity generation from coal, electricity generation from oil, electricity generation from natural gas, freight rail travel, passenger air travel, motor vehicle travel, and residential refrigeration. The data and analyses presented here demonstrate the dynamic interplay between technological innovation, market forces, and government policy. They also show that, historically, over long time periods, incremental improvements in efficiency have not succeeded in outpacing increases in the quantity of goods and services provided. Thus, the end result over these time periods has been, not surprisingly, a sizeable increase in the consumption of energy resources across all ten activities. However, there do exist a few examples of shorter, decade‐long time periods in which improvements in efficiency were able to match or outpace increases in quantity. In these cases, efficiency mandates, price pressures, and industry upheaval led to periods of reduced resource consumption. These cases suggest that with appropriate incentives, including, for example, efficiency mandates and price mechanisms, future resource consumption, and its associated environmental impacts, could be stabilized and even reduced.