Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

Article Types

Countries / Regions

Search Results (127)

Search Parameters:
Keywords = DRV

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
22 pages, 1129 KiB  
Article
Randomised Trial Shows Readymade Oral Nutritional Supplements in Older Malnourished People in the Community Improve Total Nutrient Intakes and Meet More Dietary Reference Values Without Reducing Intake from the Diet
by Marinos Elia, Trevor R. Smith, Abbie L. Cawood, Emily R. Walters and Rebecca J. Stratton
Nutrients 2025, 17(15), 2474; https://doi.org/10.3390/nu17152474 - 29 Jul 2025
Viewed by 130
Abstract
Background: There is little information about the effectiveness of oral nutritional supplements (ONS) in combatting nutrient inadequacies in primary care, where most malnutrition exists. Aim: To examine the extent to which readymade ONS add or displace the nutrients consumed in the diet and [...] Read more.
Background: There is little information about the effectiveness of oral nutritional supplements (ONS) in combatting nutrient inadequacies in primary care, where most malnutrition exists. Aim: To examine the extent to which readymade ONS add or displace the nutrients consumed in the diet and their impact on combatting dietary inadequacies. Methods: 308 free-living people >50 years with medium + high risk of malnutrition (Malnutrition Universal Screening Tool) were randomised to receive readymade low volume (2.4 kcal/mL), liquid ONS plus dietary advice (ONS + DA) or dietary advice alone (DA). Intake was assessed at baseline (24 h recall) and 4-weekly for 12 weeks (3-day diet record). Total nutrient intake was benchmarked against UK and European dietary reference values (DRVs). The proportion of energy and nutrients from the ONS that added or displaced those from the diet (net addition/displacement) was calculated. Results: ONS + DA led to significantly greater total energy and nutritional intakes, with 25/29 nutrient intakes significantly higher than with DA alone. There were no significant differences in dietary energy and nutrient intakes from food between the groups. There was little or no displacement of nutrients from the diet, with over 90% of the energy and nutrients consumed in the ONS additive to the diet. ONS + DA more than halved the number of people with nutrient intakes that failed to meet DRVs and the number of nutrients per person that did not meet DRVs compared to DA alone. Conclusions: Supplementation with readymade, low volume (2.4 kcal/mL) liquid ONS overcomes most nutrient intake inadequacies in malnourished older people in primary care without significantly reducing intake from the diet. This makes ONS an effective way to improve nutritional intakes above dietary advice alone to improve the outcomes for the management of older people at risk of malnutrition. Full article
(This article belongs to the Section Geriatric Nutrition)
Show Figures

Figure 1

17 pages, 1402 KiB  
Article
A 3-Week Inpatient Rehabilitation Programme Improves Body Composition in People with Cystic Fibrosis with and Without Elexacaftor/Tezacaftor/Ivacaftor Therapy
by Jana Koop, Wolfgang Gruber, Franziska A. Hägele, Kristina Norman, Catrin Herpich, Stefan Dewey, Christian Falkenberg, Olaf Schnabel, Burkhard Weisser, Mario Hasler and Anja Bosy-Westphal
Nutrients 2025, 17(15), 2439; https://doi.org/10.3390/nu17152439 - 25 Jul 2025
Viewed by 194
Abstract
Background: The introduction of cystic fibrosis transmembrane conductance regulator modulators, especially the triple therapy elexacaftor, tezacaftor, ivacaftor (ETI), has improved outcomes in people with cystic fibrosis (pwCF), reducing underweight but increasing overweight rates. Objectives: This study investigates the effect of ETI on appetite [...] Read more.
Background: The introduction of cystic fibrosis transmembrane conductance regulator modulators, especially the triple therapy elexacaftor, tezacaftor, ivacaftor (ETI), has improved outcomes in people with cystic fibrosis (pwCF), reducing underweight but increasing overweight rates. Objectives: This study investigates the effect of ETI on appetite control, body composition, and energy balance during a 3-week inpatient rehabilitation programme with regular exercise. Methods: In 54 pwCF (38 on ETI, 16 without ETI), changes in body composition (fat mass index, FMI; fat-free mass index, FFMI) and energy balance (calculated from body composition changes) were assessed. Appetite control was evaluated via plasma peptide YY (PYY) levels and post-exercise meal energy intake. Results: The programme significantly increased BMI (+0.3 ± 0.1 kg/m2; CI 0.1–0.4) and energy balance (+4317 ± 1976 kcal/3 weeks), primarily through FFMI gains (+0.3 ± 0.1 kg/m2; CI 0.1–0.4). Despite higher post-exercise meal energy intake and a tendency towards lower PYY levels in the ETI group, changes in body composition and energy balance did not differ between groups. This is explained by a higher prevalence of exocrine pancreatic insufficiency in the ETI group (92% vs. 50%, p < 0.001). Small sample sizes limit the interpretation of data on appetite control and energy intake. Conclusions: A 3-week inpatient rehabilitation programme improved body composition in pwCF, without resulting in a more positive energy balance with ETI therapy. This is due to a higher prevalence of pancreatic insufficiency in this group. Full article
(This article belongs to the Section Nutrition and Metabolism)
Show Figures

Figure 1

14 pages, 4026 KiB  
Article
Grain Refinement Caused by Dynamic Recrystallization Under Pulsed-Wave Laser Multi-Layer Cyclic Thermal Load
by Manping Cheng, Xi Zou, Yuan Zhu, Tengfei Chang, Qi Cao, Houlai Ju, Jiawei Ning, Yang Ding and Lijun Qiang
Coatings 2025, 15(7), 788; https://doi.org/10.3390/coatings15070788 - 3 Jul 2025
Viewed by 318
Abstract
In the Direct Energy Deposition (DED) process, the deposited material experiences intricate thermo-mechanical processes. Subsequent thermal cycling can trigger Dynamic Recrystallization (DRX) under suitable conditions, with specific strain and temperature parameters facilitating grain refinement and homogenization. While prior research has examined the impact [...] Read more.
In the Direct Energy Deposition (DED) process, the deposited material experiences intricate thermo-mechanical processes. Subsequent thermal cycling can trigger Dynamic Recrystallization (DRX) under suitable conditions, with specific strain and temperature parameters facilitating grain refinement and homogenization. While prior research has examined the impact of thermal cycling in continuous wave (CW) lasers on DRX in 316 L stainless steel deposits, this study delves into the effects of pulsed wave (PW) laser thermal cycling on DRX. Here, the thermo-mechanical response to PW cyclic thermal loading is empirically assessed, and the evolution of microstructure, grain morphology, geometric dislocation density (GND), and misorientation map during PW DED of 316 L stainless steel is scrutinized. Findings reveal that DRX is activated between the 8th and 44th thermal cycles, with temperatures fluctuating in the range of 680 K–750 K–640 K and grains evolving within a 5.6%–6.2%–5.2% strain range. After 90 thermal cycles, the grain microstructure undergoes significant alteration. Throughout the thermal cycling, dynamic recovery (DRV) occurs, marked by sub-grain formation and low-angle grain boundaries (LAGBs). Continuous dynamic recrystallization (CDRX) accompanies discontinuous dynamic recrystallization (DDRX), with LAGBs progressively converting into high-angle grain boundaries (HAGBs). Elevated temperatures and accumulated strain drive dislocation movement and entanglement, augmenting GND. The study also probes the influence of frequency and duty cycle on grain microstructure, finding that low pulse frequency spurs CDRX, high pulse frequency favors DRV, and the duty cycle has minimal impact on grain microstructure under PW cyclic thermal load. Full article
Show Figures

Figure 1

14 pages, 222 KiB  
Review
Mining Waste Materials in Road Construction
by Nuha Mashaan and Bina Yogi
Encyclopedia 2025, 5(2), 83; https://doi.org/10.3390/encyclopedia5020083 - 16 Jun 2025
Viewed by 665
Abstract
Resource depletion and environmental degradation have resulted from the substantial increase in the use of natural aggregates and construction materials brought on by the growing demand for infrastructure development. Road building using mining waste has become a viable substitute that reduces the buildup [...] Read more.
Resource depletion and environmental degradation have resulted from the substantial increase in the use of natural aggregates and construction materials brought on by the growing demand for infrastructure development. Road building using mining waste has become a viable substitute that reduces the buildup of industrial waste while providing ecological and economic advantages. In order to assess the appropriateness of several mining waste materials for use in road building, this study investigates their engineering characteristics. These materials include slag, fly ash, tailings, waste rock, and overburden. To ensure long-term performance in pavement applications, this study evaluates their tensile and compressive strength, resistance to abrasion, durability under freeze–thaw cycles, and chemical stability. This review highlights the potential of mining waste materials as sustainable alternatives in road construction. Waste rock and slag exhibit excellent mechanical strength and durability, making them suitable for high-traffic pavements. Although fly ash and tailings require stabilization, their pozzolanic properties enhance subgrade reinforcement and soil stabilization. Properly processed overburden materials are viable for subbase and embankment applications. By promoting the reuse of mining waste, this study supports landfill reduction, carbon emission mitigation, and circular economy principles. Overall, mining byproducts present a cost-effective and environmentally responsible alternative to conventional construction materials. To support broader implementation, further efforts are needed to improve stabilization techniques, monitor long-term field performance, and establish effective policy frameworks. Full article
(This article belongs to the Section Engineering)
22 pages, 654 KiB  
Article
Healthy Food Basket: Sustainable and Culturally Adaptive Nutrition for Moldova
by Rodica Siminiuc, Dinu Țurcanu and Sergiu Siminiuc
Sustainability 2025, 17(10), 4294; https://doi.org/10.3390/su17104294 - 9 May 2025
Viewed by 567
Abstract
In a global context marked by food insecurity and the increasing prevalence of non-communicable diseases, this study proposes a healthy food basket (HFB) model tailored to the demographic, cultural, and economic specificities of the Republic of Moldova which is aligned with international standards. [...] Read more.
In a global context marked by food insecurity and the increasing prevalence of non-communicable diseases, this study proposes a healthy food basket (HFB) model tailored to the demographic, cultural, and economic specificities of the Republic of Moldova which is aligned with international standards. The research employed a comprehensive methodology, including estimations of daily energy requirements using revised Harris–Benedict equations, food selection based on nutritional value, economic availability, and cultural relevance, and nutritional validation through the mean adequacy ratio (MAR), which was derived from nutrient adequacy ratios (NARs) and dietary reference values (DRVs) established by the EFSA. Nutrient intake calculations were based on food composition data and not population-level dietary surveys. Fat-soluble vitamins were excluded due to insufficient available data. The results indicate adequate intake levels of vitamins (B1, B2, B3, and C) and minerals (iron, magnesium, phosphorus, and potassium) while highlighting deficiencies in calcium and sodium that require dietary adjustments. The inclusion of traditional foods, such as kefir and salted or raw pork fat, underscores the model’s cultural acceptability and economic relevance, strengthening the integration of global nutritional principles with regional dietary habits. This study’s limitations, including the use of secondary data and the lack of empirical validation, highlight the need for longitudinal studies. The HFB model offers a replicable solution for other regions facing similar challenges, contributing to global efforts to reduce malnutrition and promote sustainable diets. Full article
Show Figures

Figure 1

17 pages, 9794 KiB  
Article
Hot Deformation Behavior and Constitutive Equation of TA15N Titanium Alloy
by Bo Huang, Yang Yu, Wenjun Ye and Songxiao Hui
Materials 2025, 18(9), 2067; https://doi.org/10.3390/ma18092067 - 30 Apr 2025
Viewed by 383
Abstract
In order to accurately obtain the deformation characteristics and suitable thermal deformation conditions of TA15N titanium alloy and guide the design of deformation process parameters, a Gleeble 1500D was used to conduct hot compression tests on the thermal deformation behavior of a deformed [...] Read more.
In order to accurately obtain the deformation characteristics and suitable thermal deformation conditions of TA15N titanium alloy and guide the design of deformation process parameters, a Gleeble 1500D was used to conduct hot compression tests on the thermal deformation behavior of a deformed TA15N titanium alloy under the condition of a strain rate of 0.01–10 s−1 and a deformation temperature of 850–1090 °C. The constitutive equations for the deformed TA15N titanium alloy based on the Arrhenius formula were developed, and the reliability of the constitutive equations was verified. A thermal processing map of the deformed TA15N titanium alloy was established by using the dynamic materials model (DMM). The research results show that the flow stress of the TA15N alloy decreased with an increase in deformation temperature and a decrease in strain rate. By utilizing electron backscattered diffraction (EBSD), the microstructural evolution and deformation process were analyzed. As the value of η decreased, dynamic recovery (DRV) gradually replaced dynamic recrystallization (DRX). This study supplies a relatively reliable processing interval for the new TA15N titanium alloy. Full article
(This article belongs to the Section Metals and Alloys)
Show Figures

Figure 1

21 pages, 24787 KiB  
Article
Constitutive Equation and Heat Distortion Behavior of TA4 Titanium Alloy
by Lifeng Ma, Wenshuai Liu, Yanchun Zhu, Ling Qin and Jingfeng Zou
Crystals 2025, 15(4), 290; https://doi.org/10.3390/cryst15040290 - 22 Mar 2025
Viewed by 463
Abstract
In this study, the high-temperature thermal deformation behavior of the TA4 alloy was investigated by thermal compression experiments. The effects of deformation temperature and strain rate on the rheological stress are described by analyzing the variation of stress–strain curves with different parameters and [...] Read more.
In this study, the high-temperature thermal deformation behavior of the TA4 alloy was investigated by thermal compression experiments. The effects of deformation temperature and strain rate on the rheological stress are described by analyzing the variation of stress–strain curves with different parameters and establishing the constitutive equation based on the dynamic material theory model. Thermal processing diagrams were established and plotted to analyze the optimal processing zone and the destabilization zone under different strains. From the thermal machining diagram, it can be concluded that the optimum machining zone at a strain of 0.9 is 1040~1133 K/0.01~0.7 s−1. The optimum machining zone at a strain of 0.6 is 940~1000 K/0.01~0.04 s−1. The optimum machining zone at a strain of 0.3 is 940~1000 K/0.01~0.08 s−1. The effects of different deformation conditions on the thermal deformation mechanism were analyzed in conjunction with EBSD characterization. The results showed that dynamic recrystallization (DRX) was the main deformation softening mechanism when at low strain rate (≤0.1 s−1). At higher strain rates (>0.1 s−1) and lower temperatures (<1083 K and ≥933 K), the main deformation softening mechanism was DRV; at higher temperatures (≥1083 K and ≤1133 K), the main deformation softening mechanism was DRX. Full article
(This article belongs to the Special Issue Advances in Processing, Simulation and Characterization of Alloys)
Show Figures

Figure 1

13 pages, 1162 KiB  
Article
A Low Dietary Quality Index in a Newly Diagnosed Inflammatory Bowel Disease Cohort: Results from a Case—Control Study
by Ravi Misra, Lovesh Dyall, Janet Kyle, Heather Clark, Jimmy Limdi, Rachel Cooney, Matthew Brookes, Edward Fogden, Sanjeev Pattni, Naveen Sharma, Tariq Iqbal, Pia Munkholm, Johan Burisch and Naila Arebi
Nutrients 2025, 17(6), 958; https://doi.org/10.3390/nu17060958 - 10 Mar 2025
Viewed by 1093
Abstract
Background: Epidemiological evidence suggests a link between the risk of IBD and diet. Macro- and micro- nutrient intake, diet quality and dietary patterns may play a pivotal role in disease pathogenesis. We aimed to study the dietary intake of newly diagnosed IBD patients [...] Read more.
Background: Epidemiological evidence suggests a link between the risk of IBD and diet. Macro- and micro- nutrient intake, diet quality and dietary patterns may play a pivotal role in disease pathogenesis. We aimed to study the dietary intake of newly diagnosed IBD patients compared to non-IBD controls. Methods: A cohort of newly diagnosed IBD patients were invited to complete the Scottish Collaborative Group Food Frequency Questionnaire (SCGFFQ) at their first clinic visit. Controls were recruited from non-IBD ambulatory patients, university students, and healthcare workers. The SCGFFQ estimates habitual diet over a 3-month period. Component nutrient data were calculated based on previous validation studies, deriving nutrient data by comparison of the SCGFFQ to actual weighted food records. Data on age, gender, ethnicity, and disease phenotype were collected. The intake of macro- and micro-nutrients was expressed as mean and standard deviation and compared using the Kruskal–Wallis test. Dietary patterns were derived using principal component analysis. Differences in the dietary patterns for age, gender, and ethnicity were analysed by logistic regression analysis. The diet quality was compared to the dietary recommendation values (DRVs) and measured using the diet quality index. Results: We enrolled 160 IBD cases (114 UC and 46 CD) and 126 non-IBD controls, and in the study, with a median age across the groups of 40 years (IQR = 24) for UC, 34 years (IQR = 29) for CD, and 36 years (IQR = 24) for non-IBD controls. The diet quality indexes for both UC and CD were low compared to controls: 59.0% (SD 18.0) for UC, 46.0% (SD 17.7) for CD, and 63.2% (SD 17.1) controls. UC patients had excessive total energy consumption (>2500 kcal/day) compared to the DRVs. UC patients reported higher retinol, vitamin D, riboflavin, niacin, vitamin B6, vitamin B12, and panthanoic acid intake, consistent with a diet rich in animal products and low in fruit/vegetable intake. This is likely driven by higher consumption of dietary patterns 2 (rich in carbohydrates, refined sugar and low fibre) and 5 (refined sugar and saturated fat) in the UC cohort. Dietary pattern 1 (variety of food items and oily fish) was less likely to be consumed by the CD population. CD patients tended to have a lower overall intake of both macro- and micro-nutrients. Conclusions: The dietary patterns identified here are a proof of concept, and the next phase of the study would be to ideally monitor these patterns in a case–control cohort prospectively, and to further understand the mechanisms behind which dietary patterns influence IBD. Patients with newly diagnosed CD have low dietary quality and lower overall intake of macro- and micro-nutrients. This finding supports the role for dietetic attention early in newly diagnosed CD. Full article
(This article belongs to the Section Nutritional Immunology)
Show Figures

Figure 1

11 pages, 233 KiB  
Article
Maternal Macronutrient Intake and Associated Risk for Gestational Diabetes Mellitus: Results from the BORN2020 Study
by Antigoni Tranidou, Ioannis Tsakiridis, Emmanuela Magriplis, Aikaterini Apostolopoulou, Violeta Chroni, Eirini Tsekitsidi, Ioustini Kalaitzopoulou, Nikolaos Pazaras, Michail Chourdakis and Themistoklis Dagklis
Biomedicines 2025, 13(1), 57; https://doi.org/10.3390/biomedicines13010057 - 29 Dec 2024
Cited by 2 | Viewed by 1317
Abstract
Background/Objectives: Limited evidence links maternal macronutrient intake to gestational diabetes mellitus (GDM) risk. Therefore, we evaluated these intakes both before and during pregnancy, comparing macronutrient data against the European Food and Safety Authorities’ (EFSA) Dietary Reference Values (DRVs). Methods: Data were prospectively collected [...] Read more.
Background/Objectives: Limited evidence links maternal macronutrient intake to gestational diabetes mellitus (GDM) risk. Therefore, we evaluated these intakes both before and during pregnancy, comparing macronutrient data against the European Food and Safety Authorities’ (EFSA) Dietary Reference Values (DRVs). Methods: Data were prospectively collected from the Greek BORN2020 epidemiologic pregnant cohort, which included 797 pregnant women, of whom 14.7% were diagnosed with GDM. A multinomial logistic regression model assessed the association between macronutrient intake and GDM, adjusting for maternal, lifestyle, and pregnancy-related factors. Results: Women with GDM had higher maternal age (34.15 ± 4.48 vs. 32.1 ± 4.89 years), higher pre-pregnancy BMI (median 23.7 vs. 22.7 kg/m2), and were more likely to smoke during mid-gestation (17.95% vs. 8.82%). Pre-pregnancy energy intake exceeding EFSA recommendations was associated with increased GDM risk (aOR = 1.99, 95%CI: 1.37–2.86). During mid-gestation, higher dietary fiber intake (aOR = 1.05, 95%CI: 1.00–1.10), higher protein intake (aOR = 1.02, 95% CI: 1.00–1.04), and higher protein percentage of energy intake (aOR = 1.08, 95%CI: 1.01–1.17) were all significantly associated with increased GDM risk. Changes from pre-pregnancy to pregnancy showed significant increases in dietary fiber intake (aOR = 1.07, 95%CI: 1.04–1.10), protein (aOR = 1.00, 95%CI: 1.00–1.01), fat (aOR = 1.00, 95%CI: 1.00–1.01), vegetable protein (aOR = 1.01, 95%CI: 1.00–1.03), animal protein (aOR = 1.00, 95%CI: 1.00–1.01), and monounsaturated fatty acid (MUFA) intake (aOR = 1.01, 95%CI: 1.00–1.02), all of which were associated with increased GDM risk. Conclusions: Energy intake above upper levels set by EFSA, as well as increased protein, MUFA, and fiber intake, although beneficial in balanced intakes, may negatively affect gestation by increasing GDM likelihood when consumed beyond requirements. Full article
16 pages, 8754 KiB  
Article
Evaluating Petrophysical Properties Using Digital Rock Physics Analysis: A CO2 Storage Feasibility Study of Lithuanian Reservoirs
by Shruti Malik, Pijus Makauskas, Ravi Sharma and Mayur Pal
Appl. Sci. 2024, 14(23), 10826; https://doi.org/10.3390/app142310826 - 22 Nov 2024
Cited by 1 | Viewed by 1080
Abstract
As the global concern over greenhouse gas emissions grows, CO2 storage in deep saline aquifers and depleted reservoirs has become crucial for climate change mitigation. This study evaluates the feasibility of Lithuanian deep saline aquifers, specifically, Syderiai and Vaskai, for effective CO [...] Read more.
As the global concern over greenhouse gas emissions grows, CO2 storage in deep saline aquifers and depleted reservoirs has become crucial for climate change mitigation. This study evaluates the feasibility of Lithuanian deep saline aquifers, specifically, Syderiai and Vaskai, for effective CO2 storage. Unlike previous theoretical analyses, it provides experimental data on static and dynamic reservoir parameters that impact CO2 injection and retention. Using micro X-ray computed tomography (MXCT) and multi-resolution scanning at 8 µm and 22 µm, digital rock volumes (DRVs) from core samples were created to determine porosity and permeability. The method, validated against analogous samples, identified a representative element volume (REV) within sub-volumes, showing a homogeneous distribution of petrophysical properties in the Lithuanian samples. The results show that DRVs can accurately reflect pore-scale properties, achieving 90–95% agreement with lab measurements, and offer a rapid, efficient means for analyzing storage potentials. These insights confirm that Lithuanian aquifers are promising for CO2 sequestration, with recommendations for further long-term monitoring and applications of this technique across the region. Full article
(This article belongs to the Special Issue CCUS: Paving the Way to Net Zero Emissions Technologies)
Show Figures

Figure 1

16 pages, 7720 KiB  
Article
Hot Deformation Behavior and Processing Maps of Vapor-Phase-Grown Carbon Nanofiber Reinforced 7075Al Composites
by Mengying Zhu, Zhefeng Xu, Junhua Wu, Satoshi Motozuka, Caili Tian, Jianglong Gu and Jinku Yu
Metals 2024, 14(11), 1245; https://doi.org/10.3390/met14111245 - 1 Nov 2024
Viewed by 905
Abstract
The present study prepared 7075Al composites reinforced with vapor-phase-grown carbon nanofibers (VGCNFs) using the spark plasma sintering (SPS) method. Constitutive equations of the composites were calculated, and thermal processing maps were constructed by performing thermal compression tests on the VGCNF/7075Al composites at deformation [...] Read more.
The present study prepared 7075Al composites reinforced with vapor-phase-grown carbon nanofibers (VGCNFs) using the spark plasma sintering (SPS) method. Constitutive equations of the composites were calculated, and thermal processing maps were constructed by performing thermal compression tests on the VGCNF/7075Al composites at deformation temperatures ranging from 300 to 450 °C and strain rates from 0.01 to 1 s−1. This study analyzed the microstructural evolution of the VGCNF/7075Al composites during the thermomechanical processing. The experimental results demonstrated that dynamic recrystallization (DRX) primarily governed the softening mechanism of VGCNF/7075Al composites during thermomechanical processing. At high strain rates, a combination of dynamic recovery (DRV) and DRX contributed to the softening behavior. The incorporation of VGCNFs results in higher dislocation density and a larger orientation deviation within the 7075Al matrix during the thermomechanical deformation process, providing stored energy that facilitated DRX. The activation energy for deformation of VGCNF/7075Al composites was 175.98 kJ/mol. The constitutive equation of the flow stress showed that a hyperbolic sinusoidal form could effectively describe the relationship between flow stress, strain, strain rate, and temperature of VGCNF/7075Al composites. The optimal thermomechanical deformation parameters for VGCNF/7075Al composites were 400–450 °C and 0.01–0.1 s−1 when the strain ranged from 0.05 to 0.15. For strains between 0.25 and 0.35, the optimal thermomechanical parameters were 380–430 °C and 0.01–1 s−1. Full article
(This article belongs to the Special Issue Numerical and Experimental Advances in Metal Processing)
Show Figures

Figure 1

10 pages, 1043 KiB  
Article
A Sensitivity and Consistency Comparison Between Next-Generation Sequencing and Sanger Sequencing in HIV-1 Pretreatment Drug Resistance Testing
by Ying Zhou, Fei Ouyang, Xiaoyan Liu, Jing Lu, Haiyang Hu, Qi Sun and Haitao Yang
Viruses 2024, 16(11), 1713; https://doi.org/10.3390/v16111713 - 31 Oct 2024
Cited by 1 | Viewed by 1774
Abstract
Next-generation sequencing (NGS) for HIV drug resistance (DR) testing has an increasing number of applications for the detection of low-abundance drug-resistant variants (LA-DRVs) in regard to its features as a quasi-species. However, there is less information on its detection performance in DR detection [...] Read more.
Next-generation sequencing (NGS) for HIV drug resistance (DR) testing has an increasing number of applications for the detection of low-abundance drug-resistant variants (LA-DRVs) in regard to its features as a quasi-species. However, there is less information on its detection performance in DR detection with NGS. To determine the feasibility of using NGS technology in LA-DRV detection for HIV-1 pretreatment drug resistance, 80 HIV-infected individuals who had never undergone antiretroviral therapy were subjected to both NGS and Sanger sequencing (SS) in HIV-1 drug resistance testing. The results reported in this study show that NGS exhibits higher sensitivity for drug resistance identification than SS at a 5% detection threshold. NGS showed a better consistency compared with that of SS for both protease inhibitors (PIs) and integrase inhibitors (INSTIs), with a figure amounting to more than 90%, but worse consistency in nucleotide reverse transcriptase inhibitors (NRTIs), with a consistency ranging from only 61.25% to 87.50%. The consistency of non-nucleotide reverse transcriptase inhibitors (NNRTIs) between NGS and SS was around 85%. NGS showed the highest sensitivity of 87.0% at a 5% threshold. The application of NGS technology in HIV-1 genotype resistance detection in different populations infected with HIV requires further documentation and validation. Full article
Show Figures

Figure 1

17 pages, 21122 KiB  
Article
Subgrain Size Modeling and Substructure Evolution in an AA1050 Aluminum Alloy during High-Temperature Compression
by Qi Yang, Tomasz Wojcik and Ernst Kozeschnik
Materials 2024, 17(17), 4385; https://doi.org/10.3390/ma17174385 - 5 Sep 2024
Cited by 2 | Viewed by 1275
Abstract
For materials with high stacking fault energy (SFE), such as aluminum alloys, dynamic recovery (DRV) and dynamic recrystallization (DRX) are essential softening mechanisms during plastic deformation, which lead to the continuous generation and refinement of newborn subgrains (2° ˂ misorientation angle ˂ 15°). [...] Read more.
For materials with high stacking fault energy (SFE), such as aluminum alloys, dynamic recovery (DRV) and dynamic recrystallization (DRX) are essential softening mechanisms during plastic deformation, which lead to the continuous generation and refinement of newborn subgrains (2° ˂ misorientation angle ˂ 15°). The present work investigates the influence of compression parameters on the evolution of the substructures for a 1050 aluminum alloy at elevated temperatures. The alloy microstructure was investigated under deformation temperatures ranging from 300 °C to 500 °C and strain rates from 0.01 to 0.1 s−1, respectively. A well-defined substructure and subsequent subgrain refinement provided indication of the evolution laws of the substructure under high-temperature compression. Corresponding experimental data on the average subgrain size under various compression conditions were obtained. Two different independent average subgrain size evolution models (empirical and substructure-based) were used and applied with several internal state variables. The substructure model employed physical variables to simulate subgrain refinement and thermal coarsening during deformation, incorporating a corresponding dislocation density evolution model. The correlation coefficient (R) and root mean square error (RMSE) of the substructure-based model were calculated to be 0.98 and 5.7%, respectively. These models can provide good estimates of the average subgrain size, with both predictions and experiments reproducing the expected subgrain size evolution using physically meaningful variables during continuous deformation. Full article
(This article belongs to the Section Metals and Alloys)
Show Figures

Figure 1

18 pages, 11847 KiB  
Article
Hot Workability and Microstructure Evolution of Homogenized 2050 Al-Cu-Li Alloy during Hot Deformation
by Zhiyong Sheng, Yuanchun Huang, Yongxing Zhao, Rong Fu, Xucheng Wang, Xi Fan and Fan Wu
Materials 2024, 17(17), 4236; https://doi.org/10.3390/ma17174236 - 27 Aug 2024
Viewed by 1336
Abstract
For this article, hot compression tests were carried out on homogenized 2050 Al-Cu-Li alloys under different deformation temperatures and strain rates, and an Arrhenius-type constitutive model with strain compensation was established to accurately describe the alloy flow behavior. Furthermore, thermal processing maps were [...] Read more.
For this article, hot compression tests were carried out on homogenized 2050 Al-Cu-Li alloys under different deformation temperatures and strain rates, and an Arrhenius-type constitutive model with strain compensation was established to accurately describe the alloy flow behavior. Furthermore, thermal processing maps were created and the deformation mechanisms in different working regions were revealed by microstructural characterization. The results showed that most of the deformed grains orientated toward <101>//CD (CD: compression direction) during the hot compression process, and, together with some dynamic recovery (DRV), dynamic recrystallization (DRX) occurred. The appearance of large-scale DRX grains at low temperatures rather than in high-temperature conditions is related to the particle-stimulated nucleation mechanism, due to the dynamic precipitation that occurs during the deformation process. The hot-working diagrams with a true strain of 0.8 indicated that the high strain-rate regions C (300 °C–400 °C, 0.1–1 s−1) and D (440 °C–500 °C, 0.1–1 s−1) are unfavorable for the processing of 2050 Al-Li alloys, owing to the flow instability caused by local deformation banding, microcracks, and micro-voids. The optimum processing region was considered to be 430 °C–500 °C and 0.1 s−1–0.001 s−1, with a dissipation efficiency of more than 30%, dominated by DRV and DRX; the DRX mechanisms are DDRX and CDRX. Full article
Show Figures

Figure 1

22 pages, 11410 KiB  
Article
An Internal-State-Variable-Based Continuous Dynamic Recrystallization Model for Thermally Deformed TC18 Alloy
by Gui-Cheng Wu, Yong-Cheng Lin, Miao Wan, Ning-Fu Zeng, Song Zhang, Hui-Jie Zhang, Ming-Song Chen and Yu-Qiang Jiang
Materials 2024, 17(16), 4026; https://doi.org/10.3390/ma17164026 - 13 Aug 2024
Cited by 4 | Viewed by 1482
Abstract
Continuous dynamic recrystallization (CDRX) is widely acknowledged to occur during hot forming and plays a significant role in microstructure development in alloys with moderate to high stacking fault energy. In this work, the flow stress and CDRX behaviors of the TC18 alloy subjected [...] Read more.
Continuous dynamic recrystallization (CDRX) is widely acknowledged to occur during hot forming and plays a significant role in microstructure development in alloys with moderate to high stacking fault energy. In this work, the flow stress and CDRX behaviors of the TC18 alloy subjected to hot deformation across a wide range of processing conditions are studied. It is observed that deformation leads to the formation of new low-angle grain boundaries (LAGBs). Subgrains rotate by absorbing dislocations, resulting in an increase in LAGB misorientation and the transition of some LAGBs into high-angle grain boundaries (HAGBs). The HAGBs migrate within the material, assimilating the (sub)grain boundaries. Subsequently, an internal state variable (ISV)-based CDRX model is developed, incorporating parameters such as the dislocation density, adiabatic temperature rise, subgrain rotation, LAGB area, HAGB area, and LAGB misorientation angle distribution. The values of the correlation coefficient (R), relative average absolute error (RAAE), and root-mean-square error (RMSE) between the anticipated true stress and measured stress are 0.989, 6.69%, and 4.78 MPa, respectively. The predicted outcomes demonstrate good agreement with experimental findings. The evolving trends of the subgrain boundary area under various conditions are quantitatively analyzed by assessing the changes in dynamic recovery (DRV)-eliminated dislocations and misorientation angles. Moreover, the ISV-based model accurately predicts the decreases in grain and crystallite sizes with higher strain rates and lower temperatures. The projected outcomes also indicate a transition from a stable and coarse-grained microstructure to a continuously recrystallized substructure. Full article
(This article belongs to the Section Metals and Alloys)
Show Figures

Figure 1

Back to TopTop