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Secondary hardening by precipitation of alloy carbides during tempering in an experimental Cr-Mo-V alloy steel was studied under continuous and isothermal conditions. Measurements of microhardness and nanohardness analysed the hardening behaviour during stage IV as a function of time, temperature, and heating rate. Scanning electron microscopy and scanning probe evidenced the carbides precipitated during stage IV. It was observed that hardening is a function of not only tempering temperature and time but also of the heating rate according to the Hollomon–Jaffe parameter. The parameter increases as the heating rate increases due to the effect on the temperature, showing a clear softening. The hardening behaviour, evaluated with the Hollomon–Jaffe parameter, was very similar regardless of the test, micro- or nanoindentation. [ABSTRACT FROM AUTHOR]

STUDY QUESTION Does platelet-rich plasma (PRP) intraovarian injection increase the number of retrieved oocytes in successive ovarian punctions among patients with poor ovarian reserve (POR)? SUMMARY ANSWER The injection of PRP increases the number of retrieved oocytes without increasing the quality of developed blastocysts. WHAT IS KNOWN ALREADY Management of women with reduced ovarian response to stimulation is one of the significant challenges in reproductive medicine. Recently, PRP treatment has been proposed as an adjunct in assisted reproduction technology, with controversial results. STUDY DESIGN, SIZE, DURATION This placebo-controlled, double-blind, randomized trial included 60 patients with POR stratified according to the POSEIDON classification groups 3 and 4. It was conducted to explore the efficacy and safety of intraovarian PRP injection. Patients were proposed to undergo three consecutive ovarian stimulations to accumulate oocytes and were randomized to receive either PRP or placebo during their first oocyte retrieval. Randomization was performed using computer-generated randomization codes. Double blinding was ensured so that neither the participant nor the investigators knew of the treatment allotted. All patients underwent three ovarian stimulations and egg retrieval procedures. ICSI was performed after a third ovarian puncture. The primary endpoint was the number of mature oocytes retrieved after PRP or placebo injection in successive ovarian punctures. PARTICIPANTS/MATERIALS, SETTING, METHODS Sixty women (30–42 years) fulfilling inclusion criteria were randomized in equal proportions to the treatment or control groups. MAIN RESULTS AND THE ROLE OF CHANCE The baseline demographic and clinical characteristics [age, BMI, anti-Müllerian hormone (AMH) levels] were comparable between the groups. Regarding the primary endpoint, the cumulative number (mean ± SEM) of retrieved mature oocytes was slightly higher in the treatment group: 10.45 ± 0.41 versus 8.91 ± 0.39 in the control group, respectively (95% CI of the difference 0.42–2.66; P  = 0,008). The number of mature oocytes obtained among all patients increased in successive egg retrievals: 2.61 ± 0.33 (mean ± SEM) in punction 1 (P1), 3.85 ± 0.42 in P2, and 4.73 ± 0.44 in P3. However, the increase was higher among patients receiving the assessed PRP treatment. In P2, the number of retrieved mature oocytes was 4.18 ± 0.58 versus 3.27 ± 0.61 in controls (95% CI of the difference: −0.30 to 2.12; P  = 0.138) and in P3, 5.27 ± 0.73 versus 4.15 ± 0.45 (95% CI of the difference: 0.12–2.12; P  = 0.029). The mean ± SEM number of developed and biopsied blastocysts was 2.43 ± 0.60 in the control group and 1.90 ± 0.32 in the treatment group, respectively (P  = 0.449). The mean number of euploid blastocysts was 0.81 ± 0.24 and 0.81 ± 0.25 in the control and treatment groups, respectively (P  = 1.000). The percentages of patients with euploid blastocysts were 53.33% (16 out of 30) and 43.33% (13 out of 30) for patients in the control and treatment groups, respectively (Fisher's exact test P  = 0.606). The overall pregnancy rate per ITT was 43% (26 out of 60 patients). However, the percentage of clinical pregnancies was higher in the control group (18 out of 30, 60%) than in the treatment group (8 out of 30, 27%) (P  = 0.018). There was also a trend toward poorer outcomes in the treatment group when considering full-term pregnancies (P  = 0.170). There were no differences between control and treatment groups regarding type of delivery, and sex of newborns. LIMITATIONS, REASONS FOR CAUTION The mechanism of the potential beneficial effect of PRP injection on the number of retrieved oocytes is unknown. Either delivered platelet factors or a mechanical effect could be implicated. Further studies will be needed to confirm or refute the data presented in this trial and to specify the exact mechanism of action, if any, of PRP preparations. WIDER IMPLICATIONS OF THE FINDINGS The increasing number of women with a poor response to ovarian stimulation supports the exploration of new areas of research to know the potential benefits of therapies capable of increasing the number of oocytes available for fertilization and improving the quality of developed blastocysts. An increase in the retrieved oocytes in both arms of the trial suggests that, beyond the release of growth factor from platelets, a mechanical effect can play a role. However, neither improvement in euploid blastocyst development nor pregnancy rates have been demonstrated. STUDY FUNDING/COMPETING INTEREST(S) This trial was supported by Basque Government and included in HAZITEK program, framed in the new Euskadi 2030 Science and Technology Plan (PCTI 2030). These aids are co-financed by the European Regional Development Fund (FEDER). The study funders had no role in the study design, implementation, analysis, manuscript preparation, or decision to submit this article for publication. No competing interests are declared by all the authors. TRIAL REGISTRATION NUMBER Clinical Trial Number EudraCT 2020-000247-32. TRIAL REGISTRATION DATE 3 November 2020. DATE OF FIRST PATIENT'S ENROLLMENT 16 January 2021. [ABSTRACT FROM AUTHOR]

Mexico is the world's leading producer and exporter of avocado (Persea americana Miller). There are few studies on soil microorganisms associated with this crop, which are important to establish the role they can play in the production system and their use in different areas of interest. In this re-search, the biodiversity of cultivable micromycetes in the soil of five avocado orchards located in two municipalities of the state of Nuevo León was determined. The isolates obtained were grouped into morphotypes and identified to genus level or grouped by common morphological characteristics. Shannon-Wiener, Simpson, and Margalef diversity indices were determined for morphotypes, as well as for and genera and groups of micromycetes with common characteristics in each orchard. The Hutcheson's test (p= 0.05) was performed to determine significant differences between Shannon-Wiener diversity index of genera and micromycetes with common characteristics between orchards. A total of 518 isolates were obtained and classified into 291 morphotypes that were grouped into 44 genera and 7 groups with common characteristics. Hutcheson's test showed that the Shannon-Wiener index of genera and groups of a single orchard is different to the others. The sterile mycelium group was the most abundant in four of the five orchards. Genera reported as phytopathogens (Fusarium, Verticillium), entomopathogens (Beauveria, Paecilomyces, Metarhizium) and mycoparasites (Trichoderma, Gliocladium) were identified. In addition, 28 new genera associated with avocado orchard soil are reported in this research. [ABSTRACT FROM AUTHOR]

The effect of thickness and chemical composition on the electrical power and thermal resistance of dilatometric specimens heated by Joule heating are analyzed in different steels, using stepped tests of constant temperature and electrical current. In the stepped constant temperature tests, the electric current necessary to maintain the target temperature in a specific time is measured, while in the electric current tests the electrical current is maintained until the maximum temperature stabilizes. The results show that the electrical power behaves linearly with the thickness associated with the transfer area, while the thermal resistance behaves potentially; both values depend on the chemical composition due to electrical resistivity. The steels with a higher concentration of alloying elements have a better response to Joule heating. However, thickness is the parameter that most influences electrical power due to changes in transfer area and electrical current density, as well as in the mass of the specimen to be heated. Finally, based on the results obtained, predictions are realized for the design of thicker specimens, maintaining the observed behavior; i. e., as the thickness of the specimen increases, the increase in electrical power and thermal resistance is maintained. [ABSTRACT FROM AUTHOR]

Tomato (Solanum lycopersicum L.) production in countries like Mexico relies heavily on the use of chemical pesticides, which can be toxic to a host of other organisms including beneficial insects and human consumers. Environment-friendly methods of controlling tomato diseases include agroecological practices, organic fungicides, and biological control. Plants' resistance against pathogens is induced by applying agents called elicitors to the plants and would lead to disease prevention or reduced severity. The objective of this research was to know the effect of three elicitor; namely, Activane (1.8 g L-1), Micobiol (3 mL L-1) and Stemicol (2.5 g L-1) plus a control on the incidence of diseases, vigor, yield and fruit quality of two cultivars of Bola tomato and Saladette in the greenhouse. Elicitors decreased the incidence and severity of presented diseases and increased plant survival. Additionally, the elicitors Micobiol® and Activane® were able to increase plant height, stem diameter, weight and fruit diameter, while Stemicol® considerably increased fruit color, °Brix and pH and Activane® increased titratable acid. In general, elicitors were able to reduce disease, increase plant survival, production and improve fruit quality. These findings provide positive directions for the possible use of these elicitors and induce resistance in plant protection. [ABSTRACT FROM AUTHOR]

This article discusses a study conducted to understand the cardiovascular remodeling and function in fetuses with tetralogy of Fallot (ToF) using echocardiography. The study included 63 ToF fetuses and 66 healthy fetuses as controls. The results showed that ToF fetuses had lower cardiac sphericity index with biventricular hypertrophy, prolonged filling time fractions, and increased cardiac index. Additionally, there were associations between certain echocardiographic parameters and postnatal outcomes. The study concludes that further research is needed to correlate these findings with postnatal echocardiography. [Extracted from the article]

This article, published in the journal Ultrasound in Obstetrics & Gynecology, discusses a study conducted from 2011 to 2023 that aimed to define the cardiovascular remodeling and function in fetuses with tetralogy of Fallot (ToF) using speckle tracking echocardiography (STE). The study included 63 ToF fetuses and 66 low-risk pregnancies as a control group. The results showed that ToF fetuses exhibited signs of cardiac remodeling, with a lower sphericity index and decreased biventricular deformation. Additionally, a higher incidence of placental diseases, such as pre-eclampsia and fetal growth restriction, was observed in pregnancies with ToF fetuses. [Extracted from the article]

This article, published in the journal "Ultrasound in Obstetrics & Gynecology," discusses a study conducted at BCNatal that aimed to describe the cord blood profile of cardiovascular biomarkers in fetuses with tetralogy of Fallot (ToF) and explore its correlation with fetal echocardiography. The study included 22 fetuses with ToF and 36 healthy controls. The results showed that ToF fetuses had significantly higher concentrations of Transforming growth factorβ (TGFβ) in their cord blood compared to normal fetuses, and these levels correlated with the severity of right ventricle outflow obstruction. The findings of this study provide new insights for further research on prognostic and preventive strategies for ToF. [Extracted from the article]

This article discusses the effectiveness of thoracoamniotic shunts in treating large macrocystic congenital cystic adenomatoid malformations (CCAM) in fetuses. The study, conducted at a fetal therapy center between 2013 and 2023, involved 8 fetuses with severe mediastinal shift and hydrops. Shunt insertion successfully reduced the size of CCAM, corrected mediastinal shift, and resolved hydrops in all cases. The study reported a postnatal survival rate of 87.5%, with premature delivery being the main complication. Overall, fetal thoracoamniotic shunting appears to have favorable outcomes for large macrocystic CCAM. [Extracted from the article]