Effect of Heat Treatment on the Microstructure and Mechanical Properties of 18Ni-300 Maraging Steel Produced by Additive-Subtractive Hybrid Manufacturing.

The present work investigates the effectiveness of two heat treatment cycles-solution treatment + aging (STA) and direct aging (DA)-on optimizing the microstructure and enhancing the mechanical properties of 18Ni-300 maraging steel (300 MS) produced by additive-subtractive hybrid manufacturing (ASHM). The STA treatment led to a fully martensitic microstructure with minor remnants of the cellular substructures associated with the solidification conditions in ASHM. DA resulted in some reverted austenite and partial dissolution of the cellular morphologies into shorter fragments. Despite the contrasting microstructures, the tensile strength and the macro- and micro-hardness were comparable between STA and DA conditions. By contrast, the potential for improving the ductility was higher with the DA heat treatment. This is attributed to the higher reverted austenite content in the samples treated by DA, i.e., up to a maximum of 13.4% compared to less than 3.0% in the STA samples. For the DA sample with the highest reverted austenite content of 13.4%, the highest local and global fracture strain values of 30.1 and 5.9 ± 0.6% were measured, while the respective values were 23.4 and 4.4 ± 0.1% for the corresponding STA sample. This work suggests that DA of 300 MS produced by ASHM is sufficient to achieve comparable hardness and tensile strength to STA, whilst maintaining reasonable ductility. Avoiding the solution treatment cycle, with its appreciably higher temperatures, could benefit the dimensional stability and surface quality that are important for ASHM of 300 MS parts.

Effect of Elevated Temperature and Annealing Time on Mechanical Properties of Ti/Cu Bimetal.

The paper presents the results of the elastoplastic properties of Ti/Cu bimetallic rods. They were obtained by extrusion and composed of a copper core with a covered titanium layer. Experiments were carried out at room temperature on virgin samples, and samples were subjected to prior annealing in the temperature range of 600-900 °C for 30, 60, and 90 min. The modern technique of impulse excitation of vibration was used to analyze the elastic properties of bimetal, obtaining the temperature and time characteristics of Young's modulus, internal friction, and resonance frequency variability. Subsequently, the samples were stretched to breakage, obtaining information on the values of limit stresses, their deformability, and the energy demand for uniform elastic-plastic deformation in terms of the effect of temperature and annealing time. The influence of thermal processes on the strengthening of the Ti/Cu bimetal was also examined, and microscopic observations and qualitative analysis of the diffusion zone at the interface of the phases were carried out. The research was to answer the question of how a short-term temperature increase in 600-900 °C affects the physical properties of Ti/Cu bimetallic rods. These rods were used as a high-density electric current carrier in metallurgical processes in environments of aggressive chemical compounds. Studies have shown that short-term annealing at elevated temperatures causes a drastic reduction in the strength of the Ti/Cu bimetal, leading to structural changes within the components, and the diffusion zone with the release of intermetallic compounds, leading to structural degradation. Heating at 900 °C for 60 and 90 min caused accelerated interface degradation and destruction of the Ti/Cu bimetal by delamination.

Advances in penile-sparing surgical approaches.

Objective: Penile cancer (PeCa) is a rare disease with a global incidence of 36 068 new cases in 2020. This accounts for 0.4% of all male malignancies. The surgical management of PeCa depends on the location of the tumour and depth of invasion. Here, we review the oncological and functional outcomes of penile-preserving surgery (PPS). Methods: A PubMed search until July 2021 on PPS for PeCa was conducted; a narrative review on different penile-sparing approaches and outcomes was performed. Results: PPS is now the standard of care in specialist centres for distal tumours not involving the corpus cavernosa. Laser therapy, glans resurfacing, and wide local excision are options for superficial lesions, whilst glansectomy is required for lesions invading into the corpus spongiosum. Conclusion: PPS aims to preserve urinary and sexual function without compromising oncological outcomes.

Case report: Corneal endothelial degeneration and optic atrophy in dentatorubral-pallidoluysian atrophy quantified by specular micrography and optical coherence tomography.

Introduction: Dentatorubral-pallidoluysian atrophy (DRPLA) is an autosomal dominant neurodegenerative disease with various neurological manifestations. Corneal endothelial degeneration and optic atrophy have been reported separately; however, there are no reports of corneal endothelial degeneration with optic atrophy. Cases: Herein, we present four related patients with DRPLA: two patients (69-year-old woman and 80-year-old man) who exhibited both corneal endothelial degeneration and optic atrophy and another two (49- and 51-year-old women, respectively) who exhibited only corneal endothelial degeneration. We quantified the reduction in corneal endothelial cell density (ECD) and hexagonality using specular microscopy and thinning of the circumpapillary retinal nerve fiber layer (RNFL) using optical coherence tomography (OCT). Conclusion: This is the first report of DRPLA accompanied by corneal endothelial degeneration and/or optic atrophy, which were both quantified based on the corneal ECD and the circumpapillary RNFL thickness using specular micrography and OCT, respectively. The pathophysiological mechanism is unclear; however, the involvement of the nuclear receptor TLX interacting with atrophin-1 may be implicated in ophthalmic manifestations of DRPLA. Therefore, we recommend performing specular micrography and/or OCT when patients with DRPLA experience visual disturbances.

Quantitative EEG in Childhood Attention Deficit Hyperactivity Disorder and Learning Disabilities.

The clinical use of the quantitative EEG (QEEG) from the pioneering work of John has received a new impetus thanks to new neuroimaging techniques and the possibility of using a number of normative databases both of normal subjects and of subjects with definite pathologies. In this direction, the term personalized medicine is becoming more and more common, a medical procedure that separates patients into different groups based on their predicted response to the quantitative EEG. This has allowed the study of single subjects and to customize health care, with decisions and treatments tailored to each individual patient, as well as improvement of knowledge of the pathophysiological mechanisms of specific diseases. This review article will present the most recent evidence in the field of developmental neuropsychiatric disorders obtained from the application of quantitative EEG both in clinical group studies (attention deficit hyperactivity disorder, developmental dyslexia, oppositional defiant disorder) and in individual case studies not yet published.

ß -glucan from saccharomyces cereviseae in skim yogurt production / ß-Glucana de Saccharomyces cereviseae na produção de iogurte desnatado

The demand for functional foods has increased in recent years, following a market trend in which the consumer values foods associated with health improvements. Skim milk yogurts were produced with yeast ß-glucan (YBG, 0.5 and 1.0 %) isolated from Saccharomyces cerevisiae and compared with full fat (FFY) and skim milk (SMY) yogurt as controls. The samples were analyzed for physical, chemical, color,syneresis, culture starter count, textural, microstructure and sensory attributes. Yeast ß-glucan was not able to retain the serum of yogurts during cold storage. Skim yogurt firmness increased with the addition of 0.5% yeast ß-glucan, presenting a more compact microstructure. Yogurts containing yeast ß-glucan had low scores by the untrained panelists in the sensorial analysis (0.5% YBG overall acceptance 5.2, FFY 6.8, SY 6.3) and low purchase intention. Thus, although similar characteristics were observed, low scores in the sensorial analysis and purchase intention were a barrier to commercializing skim milk yogurt with yeast ß-glucan developed in the present study

A demanda por produtos funcionais tem aumentado recentemente, seguindo um padrão no qual os consumidores valorizam os alimentos que são associados a melhoria da saúde. Iogurte desnatado foi produzido com ß-glucana extraída de Saccharomyces cerevisiae e comparado com iogurte integral e iogurte desnatado. O iogurte desnatado contendo ß-glucana não reteve soro durante a estocagem refrigerada. A firmeza do produto aumentou com a adição de 0,5% de ß-glucana e sua microestrutura foi mais compacta. Iogurtes contendo ß-glucana apresentaram menor escore na análise sensorial. Assim, embora características semelhantes tenham sido observadas, os baixos escores da análise sensorial são uma barreira para a comercialização de iogurte desnatado contendo ß-glucana produzido no presente estudo

A new computer vision-based approach to aid the diagnosis of Parkinson's disease.

BACKGROUND AND OBJECTIVE: Even today, pointing out an exam that can diagnose a patient with Parkinson's disease (PD) accurately enough is not an easy task. Although a number of techniques have been used in search for a more precise method, detecting such illness and measuring its level of severity early enough to postpone its side effects are not straightforward. In this work, after reviewing a considerable number of works, we conclude that only a few techniques address the problem of PD recognition by means of micrography using computer vision techniques. Therefore, we consider the problem of aiding automatic PD diagnosis by means of spirals and meanders filled out in forms, which are then compared with the template for feature extraction. METHODS: In our work, both the template and the drawings are identified and separated automatically using image processing techniques, thus needing no user intervention. Since we have no registered images, the idea is to obtain a suitable representation of both template and drawings using the very same approach for all images in a fast and accurate approach. RESULTS: The results have shown that we can obtain very reasonable recognition rates (around ≈67%), with the most accurate class being the one represented by the patients, which outnumbered the control individuals in the proposed dataset. CONCLUSIONS: The proposed approach seemed to be suitable for aiding in automatic PD diagnosis by means of computer vision and machine learning techniques. Also, meander images play an important role, leading to higher accuracies than spiral images. We also observed that the main problem in detecting PD is the patients in the early stages, who can draw near-perfect objects, which are very similar to the ones made by control patients.

Analise por imagem e microscopia electrônica por varredura das farinhas extrudadas de arroz e maracujá / Image analysis and scanning electron microscopy of the extruded rice and passiflora

Um dos processos industriais que tem se mostrado eficiente na obtenção de produtos alimentícios é a extrusão. Este processo possibilita a obtenção de uma variedade de produtos como os snacks, as farinhas pré-gelatinizadas e os cereais pré-cozidos. O objetivo deste trabalho foi verificar as diferenças provocadas pelas condições de processamento, tais como percentual de farinha de maracujá nas amostras, umidade da mistura e temperatura na 3ª zona do extrusor, na estrutura interna dos extrudados. As imagens das amostras foram visualizadas através de um scanner e a análise da microestrutura das farinhas mistas extrudadas selecionadas foi realizada em um microscópio eletrônico de varredura (MEV), modelo TM 3000 Hitachi (Tókio, Japão), acoplado com o sistema de energia dispersiva de raios- -X Quanta EDS (Bruker, Karlsruhe, Alemanha), utilizando aumentos de 100x e 600x. Analisando as micrografias, de modo geral, observa-se que a farinha de arroz branco polido apresenta os componentes da sua estrutura aglomerados e íntegros. Já as farinhas mistas com diferentes concentracoes de farinha de maracujá, que foram submetidas ao processo de extrusão, apresentam aspecto de uma massa compacta, amorfa, em que não se distingue o amido e a proteína. De modo geral, pode-se concluir que houve diferença na estrutura interna dos extrudados, conforme se aumentou a concentração de farinha da casca de maracujá, verificando a presença de superfícies irregulares, provavelmente provocadas pelo aumento do teor de proteína nestas farinhas extrudadas.

One of the industrial processes that have proven effective in getting food products is extrusion. This process makes it possible to obtain a variety of products such as snacks, the gelatinization meals and precooked cereals, the aim of this study was to determine the differences caused by the processing conditions, such as passion fruit flour in the samples, humidity mixing and 3rd zone temperature in the extruder, the internal structure of the extrudates. Images of the samples were viewed through a scanner, as proposed by Tan, Gao and Hsieh (1994) and the analysis of the microstructure of selected extruded mixed flours was conducted in a scanning electron microscope (SEM), model TM 3000 Hitachi (Tokyo, Japan) coupled with energy dispersive x-ray system Quanta EDS (Bruker, Karlsruhe, Germany) using 100x and 600x. Analyzing the micrographs, in general, it is observed that the polished white rice flour shows the components of its agglomerated structure and integrity. Since the mixed flours were subjected to the extrusion process, have appearance of a compact mass, amorphous, that is indistinguishable starch and protein. In general, the extruded samples can verify the presence of irregular surface with a smooth and ridged parts and some small holes, probably formed by air bubbles generated during expansion.

Isolation of a lytic bacteriophage against virulent Aeromonas hydrophila from an organized equine farm.

A bacteriophage (VTCCBPA6) against a pathogenic strain of Aeromonas hydrophila was isolated from the sewage of an organized equine breeding farm. On the basis of TEM analysis, phage belonged to family Myoviridae. PCR amplification and sequence analysis of gp23 gene (encoding for major capsid protein) revealed phylogenetic resemblance to T4 like virus genus. Protein profiling by SDS-PAGE also indicated its resemblance to T4 like phage group. However, the comparison of its gp23 gene sequence with previously reported phages showed similarity with T4-like phages infecting Enterobacteriaceae instead of Aeromonas spp. Thus, to our knowledge, this report points toward the fact that a novel/evolved phage might exist in equine environment against A. hydrophila, which can be potentially used as a biocontrol agent.

Coacervation of Elastin-Like Recombinamer Microgels.

The investigation of the coacervation (self-aggregation) behavior of biomicrogels which can potentially be used as drug carriers is an important topic, because self-aggregation can not only cause loss of activity, but also toxicity and immunogenicity. To study this effect microgels from elastin-like recombinamer are synthesized using miniemulsion technique. The existence of coacervation for such microgels, at different concentrations and temperatures, is studied and proved by cryo-field emission scanning clectron microscopy (cryo-FESEM), cryo-transmission electron microscopy (cryo-TEM), and by a novel (1) H high-resolution magic angle sample spinning (HRMAS), nuclear magnetic resonance (NMR) spectroscopy, and relaxometry methods. The findings by (1) H HRMAS NMR spectroscopy and relaxometry show simultaneous processes of volume phase temperature transition and coacervation with different sensitivity for hydrophobic and hydrophilic amino acid side-chains in the microgel. The coacervation process is more evidential by the behavior of glycine α-CH2 , (1) H NMR peak as compared to the proline ß-CH2 .

Actividad antioxidante, análisis fitoquímico y micrografía analítica de hojas de Castela tweedii (Simaroubaceae) / Antioxidant activity, phytochemical analisys and micrographic characterization of Castela tweedii (Simaroubaceae) leaves

Castela tweedii is a small tree belonging to Simaroubaceae family. Infusions of its leaves are used in folk medicine to treat gastrointestinal disorders and diarrhea. In this work, we evaluated the antioxidant activity of ethanol and dicloromethane leaves extracts against DPPH radical (2,2-difenilpicrilhidrazil) in order to justify, at least in part, its popular use. Ethanol extract showed scavenging activity, with an IC50=0.1288 mg/mL. Responsible compounds for these activity were tannins, flavonoids and phenylcarboxilic acids, among them we identified rutine and chlorogenic acid. Microscopic and histochemical analysis of leaves was carry out to developed useful characterizations that will allow a future identification and authentication of raw material: such as, the presence of mucilaginous hypodermis, leaf of dorsiventral structure, 1 to 2 rows of empalisade parenchyma with tannin deposits, anomocytic stomata in low epidermis and simple, unicellular trichomes in both epidermis.

Castela tweedii es un árbol de bajo porte perteneciente a la Familia Simaroubaceae, las infusiones de sus hojas son utilizadas en la medicina popular Argentina para el tratamiento de desordenes gastrointestinales y diarreas. Con el objetivo de fundamentar el uso popular de esta especie se evaluó la actividad antioxidante de los extractos etanólicos y diclorometánicos de forma cuantitativa y cualitativa frente al radical 2,2-difenilpicrilhidrazilo (DPPH); el extracto etanólico demostró actividad obteniéndose una CI50= 0,1288 mg/mL. El análisis fitoquímico mostró que los compuestos responsables de esta actividad fueron taninos, flavonoides y ácidos fenilcarboxílicos, entre ellos se identificó rutina y ácido clorogénico. Además se realizó el estudio morfoanatómico e histoquímico de las hojas que aportó datos de valor diagnostico para el control de calidad de la droga vegetal: presencia de una hipodermis mucilaginosa, estructura dorsiventral con una a dos hileras de parénquima en empalizada conteniendo taninos, estomas anomocíticos solo en la epidermis abaxial y tricomas simples unicelulares en ambas epidermis.

Organotypic Culture of Organ of Corti with Floating Drop Method from Newborn Rat / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Organotypic culture of organ of Corti maintains the basic organization of the spiral lamina and can conserve several factors responsible for the neuronal growth of the nervous components. The explant culture technique has been widely used in organ culture system, however, the floating drop method using collagen gel was also developed as a simple and reliable method. In order to study the effect of growth factors on the regenerative and protective ability of cochlear hair cells, we first had to establish an in vitro model of the inner ear. MATERIALS AND METHODS: Organ of Corti was obtained from newborn rats and cultured with the floating drop method using collagen gel. Immunohistochemical staining was used to visualize the stereocilia and scanning electron microscopic study was also carried out. RESULTS: Explants were maintained up to 10 days without contamination. Morphologically, immunofluorescent staining with phalloidin showed well preserved outer and inner hair cells with stereocilia on the second day of culture. On the tenth day of culture, the staining result showed inner and outer hair cells, although the stereocilia were poorly stained. In scanning electron microscopic examination, an explant on the tenth day of culture showed preserved outer and inner hair cells and stereocilia, although damaged hair cells and stereocilia were also observed. CONCLUSION: The floating drop method was an appropriate method for maintaining the organ of Corti in vitro with the advantage being the easiness in its manual manipulation.