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1.
Materials (Basel) ; 16(17)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37687570

RESUMO

It is known that a number of parts that operate in liquid media, such as the propellers of motorboats and pleasure river vessels, as well as the rotors of household pumps and the radiators and pumps in the cooling system of motor vehicles are made, as a rule, of aluminum-based alloy. Research during maintenance leads to the conclusion that, in certain operating conditions, due to the turbulent character of the flow, with pressure drops to below the vaporization level, it inevitably reaches the threshold of cavitation, which manifests itself through its effects, especially through erosion. To increase the lifetime, these alloys are currently subjected to techniques to improve the structure's resistance to the cyclic stresses of cavitational microjets. Among these techniques are volumetric heat treatments, which lead to changes in the microstructure and mechanical property values, with an effect on the behavior and resistance to cavitation erosion. This paper studies the influence of heat aging treatments on the cavitation erosion behavior of an aluminum alloy type 6082, in the cast state. The heat treatments applied were 140 °C/1 h, 12 h, 24 h and 180 °C/1 h, 12 h, 24 h. The MDEmax and MDERs parameters were determined and a correlation could be made between the values of the mechanical-resilient characteristics and the resistance to cavitation erosion in the case of aluminum alloy 6082.

2.
Diagnostics (Basel) ; 12(9)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36140456

RESUMO

Background: The most commonly known cardiac effect of gestational diabetes mellitus (GD) in the fetus is hypertrophic cardiomyopathy, but recent studies show that it is preceded by subclinical cardiac dysfunction. This study aimed to assess the effect of GD on fetal cardiac geometry and contractility by two-dimensional speckle-tracking technology. Methods: We performed a prospective observational study that included 33 pregnant patients with GD and 30 healthy individuals. For all fetuses, a four-chamber 3 s cine-loop was recorded and analyzed with Fetal Heart Quantification (FetalHQ®), a novel proprietary speckle-tracking software. The following cardiac indices were calculated: global sphericity index (GSI), global longitudinal strain (GLS), fractional area change (FAC), and 24-segment end-diastolic diameter (EDD), fractional shortening (FS), and sphericity index (SI) for both ventricles. Demographic and cardiac differences between the two groups were analyzed, as well as intra-rater and inter-rater reliability. Results: There were significant changes in right ventricular FAC and FS for segments 4−24 in fetuses exposed to GD (−1 SD, p < 0.05). No significant differences were detected for GSI, GLS, EDD, or SI for either ventricle. Conclusions: Fetuses exposed to GD present impaired right ventricular contractility, especially in the mid and apical segments.

3.
Exp Ther Med ; 21(6): 606, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33936263

RESUMO

Human immunodeficiency virus (HIV) is an RNA (ribonucleic acid) virus that causes acquired immunodeficiency syndrome (AIDS). This disease has a major socioeconomical impact. The aim of the present study was to assess the fetal heart structure and function in HIV-positive pregnant women on highly active antiretroviral therapy (HAART). This is a prospective study conducted between January, 2018 and December, 2019. The hearts of fetuses from 14 HIV-positive pregnant women on HAART were assessed. Statistically significant sex-related cardiac changes in HIV-exposed uninfected fetuses of pregnant women on HAART were found. A narrow aorta was detected in female fetuses and a smaller left ventricular transverse diameter in male fetuses. Overall, the myocardial performance index remained unaltered. The impact of antiretroviral therapy on fetal heart seems to be sex-related. Accurate and complete information about the risks and benefits of antiretroviral treatment and management strategies to improve fetal outcomes may also ensure better compliance of the mothers to this treatment.

4.
Exp Ther Med ; 20(6): 203, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33123232

RESUMO

Association between phenotype and follicle-stimulating hormone (FSH) receptor and FSH beta chain genotype was evaluated in women with ovarian dysfunction. FSH receptor gene single nucleotide polymorphisms (SNPs) were analyzed by restricted fragment length polymorphism (RFLP) technique. Three groups were analyzed: two groups formed of poor responders (women with ovarian dysfunctions caused by endometriosis and patients who underwent ovarian stimulation protocols) and a third good responders group (normal-ovulatory women who gave birth to naturally conceived children). A higher average level of basal FSH values were found in mutants in the A919G/Ala307Thr/rs6165 or A2039G/Asn680Ser/rs6166 tests (7.16±1.09; P=0.659). Anti-mullerian hormone (AMH) below 1.2 ng/ml was associated with a higher frequency of mutations: 33.3% A919G/Ala307Thr and A2039G/Asn680Ser (P=0.137) and also in 66.6% FSH receptor less frequent polymorphism (c.-29G>A) rs 1394205 (P=0.522). The age, day 3 FSH, and AMH levels are widely used to investigate female infertility. However, we have not yet found the ideal biomarker to determine the best outcome and treatment plan for our patients. We cconsider that genetic markers will become the future in the personalization of controlled ovarian stimulation treatment in the upcoming period.

5.
J Food Sci Technol ; 56(6): 2940-2948, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31205349

RESUMO

Fresh onions (Allium cepa L.) emit volatile organic compounds (VOCs) naturally in very low concentrations. The aim of the present study was to determine the emission rate of low-boiling VOCs from healthy and naturally infected onion bulbs at 4, 15, and 25 °C and to evaluate the applicability of the VOC method to monitor quality changes during 12 weeks of storage of two cultivars ('Hystand' and 'Hoza') of yellow onions. VOCs were extracted from the headspace of bulbs by solid phase micro-extraction (SPME) up to 5 times during storage and analyzed by gas chromatography-mass spectrometry (GC-MS). A total of twenty-nine compounds were measured and twenty-seven of these were identified while thirteen were reported for the first time from yellow onion bulbs. Acetone (0.10-18.0 nmol kg-1 day-1), dimethyl disulfide (0.12-18.9 nmol kg-1 day-1) and hexanal (0.05-4.40 nmol kg-1 day-1) were among the most abundant volatiles emitted from healthy bulbs. The concentration of these compounds as well as the total volatiles decreased with time in storage. However, microbial infection resulted in higher emission of propene, carbon disulfide, isoprene, pentane, 2-methylfuran, 3-methylfuran, 1-propenethiol, hexane, and methyl propyl sulfide, indicating that VOC emission may be used as an indicator to monitor natural senescence and decay of stored onion bulbs.

6.
Perm J ; 21: 16-179, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28633726

RESUMO

INTRODUCTION: Intussusception usually is associated with children, rarely with adults. CASE PRESENTATION: A 42-year-old pregnant woman (29 weeks' gestation) reported mild pain in the upper aspect of the abdomen after an intense physical effort. Ultrasound examination found a normally evolving pregnancy and a bowel obstacle, without bowel distention. Because it was not a surgical emergency at the time of evaluation, she was sent to the hospital's Obstetrics Department. The patient's symptoms worsened the next day. Ultrasound examination revealed dilated bowel loops and free fluid. Strangulated epigastric hernia was suspected. Computed tomography was not performed. Exploratory laparotomy revealed a small-bowel intussusception, which was successfully manually reduced, and no leading point was found. Four days later, she delivered a premature baby boy. Two days later the necrotized reduced ileal loop had to be surgically removed because of the patient's altered status. After this procedure, the patient's recovery was uneventful. DISCUSSION: To our knowledge, this is the first case of small-bowel intussusception in a pregnant woman reported in the literature.


Assuntos
Intussuscepção/diagnóstico por imagem , Intussuscepção/cirurgia , Período Pós-Parto , Complicações na Gravidez/diagnóstico por imagem , Adulto , Feminino , Humanos , Intestino Delgado/diagnóstico por imagem , Intestino Delgado/patologia , Intestino Delgado/cirurgia , Intussuscepção/patologia , Necrose/patologia , Necrose/cirurgia , Gravidez , Complicações na Gravidez/patologia , Ultrassonografia
7.
Food Chem ; 232: 579-586, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28490114

RESUMO

The quality of leafy green vegetables changes during storage. Leaves become yellow or disintegrate, and an off-odor may develop. In addition, small amounts of volatile organic compounds (VOCs) are released. In this study, the release of acetone, carbon disulfide, dimethyl sulfide, nitromethane, pentane, 3-methylfuran, 2-ethylfuran, and dimethyl disulfide from wild rocket with different initial qualities was monitored during 8d storage at 10°C and correlated to aerobic bacteria counts, yeast and mold counts, and degree of tissue disintegration. The release of VOCs, except for 3-methylfuran, was influenced by the initial quality of the leaves. The release of pentane and 2-ethylfuran was related to the degree of tissue disintegration, and the release of dimethyl sulfide and dimethyl disulfide was related to the total aerobic bacteria count. The results demonstrated that VOCs can be used as markers for monitoring the complex quality changes taking place in packaged fresh produce during storage.


Assuntos
Folhas de Planta , Compostos Orgânicos Voláteis , Armazenamento de Alimentos , Verduras
9.
PLoS One ; 10(7): e0132271, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26186361

RESUMO

BACKGROUND: In Romania, a country with no organized national surveillance program regarding cervical cancer, the early diagnosis of HPV (Human Papilloma Virus) infections is a major requirement, especially in HIV-infected women. The objective of this study was to determine the HPV prevalence and type distribution in young HIV-positive women and to assess the difference in the risk factors for developing cervical cancer compared to those of HIV-negative women. METHOD: We conducted one cross-sectional cohort study from June 2013-September 2014, including 1,032 women: 992 HIV- women who were 36.5 years old (limits: 17 ÷ 84) and 40 HIV + women who were 22.9 years old (limits: 17 ÷ 30) with iatrogenic HIV infected. We detected HPV types with the Linear Array HPV Genotyping test (Roche, Romania). RESULTS: DNA/HPV was detected in 18/40 (45%) of the HIV+ patients and in 350/992 (35.2%) of the HIV- patients (OR = 1.5, 95%CI 0.76÷2.96). After age adjustment, the overall HPV prevalence was 51.6% in HIV+ versus 63.2% in HIV- women aged under 25, and 22.2% in HPV+ versus 47.2% in HIV- women aged 25-34. We detect HIV being a risk factor for acquiring multiple HPV type infections (OR = 2.30, 95% CI 0.88÷5.97). The eight most common HPV types (high-risk, and low-risk) for women below age 30, HIV+ / - were: HPV 16, 18, 31, 51, 58, 68, and 6 and 82 respectively. To assess the risk factors of HIV-positive women for acquiring HPV infection, we analyzed the CD4/µL, ARN/HIV copies/µL, the age group, the number of sexual partners, smoking, and the type of HPV infection (single versus multiple infections). We found that the number of sexual partners and smoking are statistically significant risk factors. CONCLUSION: Even though there are no significant differences regarding the prevalence of HPV infection in HIV + versus HIV - patients, multiple infections were more frequent in the first group. In our study group young HIV-infected patients under HAART therapy, high number of sexual partners (more than 3) and smoking were detected to be risk factors. Future organized screening for HPV infection using sensitive and specific methods are necessary at the national level in Romania.


Assuntos
Detecção Precoce de Câncer , Soropositividade para HIV/complicações , Soropositividade para HIV/virologia , Testes de DNA para Papilomavírus Humano/métodos , Prevenção Primária , Neoplasias do Colo do Útero/prevenção & controle , Neoplasias do Colo do Útero/virologia , Adulto , Feminino , Humanos , Reprodutibilidade dos Testes , Romênia , Adulto Jovem
10.
J Food Sci ; 79(7): E1366-71, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24984574

RESUMO

UNLABELLED: Packaging and storage of fresh-cut fruits and vegetables are a challenging task, since fresh produce continue to respire and senesce after harvest and processing accelerates the physiological processes. The response on respiration and ethylene production rates of fresh produce to changes in O2 and CO2 concentrations and temperature has been extensively studied for whole fruits but literature is limited on processed and mixed fresh-cut fruits. This study aimed to investigate the effects of mixing various proportions of fresh-cut fruits (melon chunks, apple slices, and pineapples cubes) on respiration and ethylene production rates and to develop predictive models for modified atmosphere packaging. The experiment was designed according to a simplex lattice method and respiration and ethylene production rates were measured at 10 °C. Results showed that single component pineapple cubes, apple slices, and melon chunks, in this order, had significant constant coefficients (P = 0.05) and the greatest impact on respiration rate while the interactive binary and tertiary coefficients were insignificant. For ethylene production rates, single component apple slices, melon chunks, and pineapple cubes, and their 3-component mixtures, in this order, had significant constant coefficients (P = 0.05) while binary coefficients were insignificant. Mathematical models were developed and validated; the cubical model was the best to describe the influence of proportion of fruit on respiration and ethylene production rates, however, considering simplicity the linear part of the model is recommended to quantify respiration and ethylene production rates of mixed fresh-cut fruits. PRACTICAL APPLICATION: This research helps to quantify the ethylene production and respiration rates of multicomponent mixed fresh-cut fruit, which then can be used for packaging design of fresh-cut produce.


Assuntos
Ananas , Cucurbitaceae , Etilenos/metabolismo , Malus , Consumo de Oxigênio , Atmosfera , Embalagem de Alimentos , Frutas , Temperatura
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