Body Part Selection for Size Classification of Two Trichogramma Species.

Body size is an important morphological characteristic that covaries with the quality of parasitoids and predators. Data show that the larger the organism is, the better the biological parameters and the host location by natural enemies in the field. The standard way of evaluating the size of parasitoids of the genus Trichogramma (Hymenoptera: Trichogrammatidae) is by measuring the tibia, but using only one body part to estimate the size of organisms can lead to miscalculations. In this paper, commercial Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae) and Trichogramma galloi Zucchi, 1988 (Hymenoptera: Trichogrammatidae) were mounted on slides for microscopy and photographed, and the photographs were used to measure their antennae, scutellum, ovipositor, tibia, and wing. Principal component analysis (PCA) and linear discriminant analysis (LDA) were performed to select the body part that best represents their size. PCA showed that all body parts represented size in a similar way, and LDA showed that the ovipositor was the most representative. We conclude that the best body parts for representing the size of the Trichogramma species studied are the wing and ovipositor, and at least two body parts are needed to detect two size groups.

Advancing ethanol content determination in hydrogels: non-destructive and operational methods for health and criminal inspections.

The significance of accurate determination of ethanol content in hydrogel formulations was accentuated during COVID-19 pandemic coinciding with the heightened demand for sanitizing agents. The present article proposes three robust methodologies for this purpose: Fourier Transform Infrared Spectroscopy (FTIR), Raman spectroscopy, and Densitometry with matrix effect correction by Near-Infrared Spectroscopy (NIR). All three methods demonstrated outstanding linearity (R2 ≥ 0.99) and minimal errors (< 1.7%), offering simplicity and operational efficiency. FTIR and Raman, being non-destructive and requiring minimal preparation, enable practical on-site analysis capabilities, underscoring the potential of the spectroscopic methods to expedite health investigations and inspections, empowering on-site ethanol determination, and relieving the burden on official laboratories. Additionally, the densitometry with NIR-based approach showcased superior accuracy and precision compared to spectroscopic methods, meeting validation criteria while offering operational advantages over the costly official distillation-based method. Therefore, it stands as a reliable and reproducible technique for comprehensive health and criminal compliance assessments, making it a compelling alternative for both industry and official laboratories.

Treatment of varicose great saphenous vein with endovenous laser alone or combined with eco-guided foam sclerotherapy: A randomized controlled trial.

Objectives: This study compares Endovenous Laser Ablation (EVLA) alone versus combined with ultrasound-guided foam sclerotherapy (UGFS) for Great Saphenous Vein (GSV) insufficiency. Methods: Sixty patients were randomly allocated to EVLA or EVLA-UGFS groups which focused on GSV occlusion rates, complications, additional treatments, and quality of life (QoL) changes. Results: Among 55 participants, the EVLA group had higher 12-month occlusion rates (92.3% vs. 75.8%, p = 0.11). Nervous injury (NI) was rarer in EVLA-UGFS (3.4% vs. 23.1%, p = 0.04). No significant difference in other complication rates (p > 0.05). QoL improved in both groups (p < 0.001). EVLA-UGFS required more subsequent procedures (24.1% vs. 7.7%, p = 0.03). Conclusions: EVLA and EVLA-UGFS effectively treat GSV insufficiency, enhancing QoL. The combined method reduces NI risk but may require more follow-up procedures.

Impact of Obesity on Cardiac Autonomic System Functioning in Military Police Officers.

INTRODUCTION: Cardiac autonomic system functioning may be altered by obesity leading to cardiovascular diseases and associated complications. Military police officers are exposed to traditional and occupational risk factors for the development of CVD, however data on the cardiovascular health in this population is still scarce. AIM: In this cross-sectional study, we investigated the impact of obesity on cardiac autonomic modulation and the hemodynamic profile in male active-duty military police officers. METHODS: The body composition of the volunteers was assessed by octapolar electrical bioimpedance. Participants were classified as non-obese or obese in accordance with their body fat, with further subgroups as physically active obese or insufficiently active obese using International Physical Activity Questionnaire (IPAQ). Cardiac autonomic modulation was assessed by heart rate variability and the automatic oscillometric method allowed us to assess hemodynamic features. RESULTS: 102 military police officers from the state of São Paulo participated in the study. Cardiac autonomic modulation revealed significant impairment in time and frequency domains and non-linear methods in the obese group compared to the non-obese (p < 0.05). A higher physical activity level did not alter these results in the obese group. However, no significant differences in the hemodynamic profile were observed between groups (p > 0.05). CONCLUSION: These findings suggest a negative association between obesity and cardiac autonomic modulation in military police officers, unaffected by increased physical activity.

Supplementation with long-acting injectable progesterone 3 days after TAI impaired luteal function in buffaloes.

Three experiments were conducted to evaluate the effects of long-acting injectable progesterone (iP4) in buffalo cows. In Experiment 1, ovariectomized buffaloes received 300 mg (iP300) or 600 mg (iP600) of iP4, and serum P4 concentrations were evaluated. In experiment 2, three groups were compared: control or administration of 300 mg of iP4 3 (iP4-D3) or 6 days (iP4-D6) after timed artificial insemination (TAI). On day 16, reproductive tract was recovered for conceptus, endometrium, and corpus luteum (CL) analysis. In experiment 3, pregnancy per AI (P/TAI) and proportion of pregnancy losses were evaluated after administration of 300 mg of iP4 3 (iP4-D3) or 6 days (iP4-D6) after TAI in lactating buffaloes. In experiment 1, serum P4 concentrations remained over 1 ng/mL for ~ 3 days in both groups. The 300 mg dose was used in subsequent experiments. In experiment 2, CL weight and endometrial glands density were decreased, and conceptus length was increased in iP4-D3 compared to control and to iP4-D6 (P < 0.05). Transcript abundance of Prostaglandin F Receptor (FP) and ISG15 in CL and of ISG15 and MX1 in endometrium was greater in iP4-D3 when compared to control and to iP4-D6 (P < 0.05). In experiment 3, there was no difference among experimental groups for P/TAI at D30 and pregnancy losses (P > 0.1); however, iP4-D3 presented a lower P/TAI at day 60 (41.7%) when compared to control (56.8%) and iP4-D6 (57.7%; P = 0.07). In conclusion, administration iP4 at 3 days after TAI affects CL development and consequently decreases final pregnancy outcome in buffaloes.

Irgafos 168 and Irganox 1076 as new cocaine cutting agents: A COVID-19 pandemic impact on cocaine profiling and trafficking in Brazil.

BACKGROUNDS: Restrictions in movement and closure of borders imposed by the Sars-Cov- 2 worldwide pandemic have affected the global illicit drug market, including cocaine trafficking. In this scenario, comparing cutting agents added to the cocaine and the drug purity are valuable strategies to understand how the drug trade has been impacted by the pandemic. METHODS: In this work, 204 cocaine salt materials seized in the Brazilian Federal District, before (2019) and during COVID-19 pandemics (2020) were analyzed by two analytical techniques: gas chromatography-mass spectrometry (GC-MS) and Fourier-transform infrared spectroscopy (FTIR). Statistical analyses, including Principal Component Analysis (PCA), were applied to evaluate the COVID-19 pandemic impact in the local market. Bibliometric analysis was performed as a forensic intelligence tool. RESULTS: From 2019-2020, cocaine average purity decreased 26 % while the frequency of cutting agents, as caffeine and anesthetics (lidocaine, tetracaine) increased. The high percentage of unknown were increased. Different cocaine profiling seized in 2020 showed new cutting agents, such as Irganox 1076, and Irgafos 168, indicating a trend on new adulterants/diluents introduced in the local market to mitigate the local drug shortage. Also in 2020, there was an increase in the local cocaine seizures, despite of the cocaine drug purity decreased by 26 % compared to 2019. CONCLUSIONS: Taken together, these data showed that the covid-19 pandemics has impacted cocaine trafficking in the Brazilian Federal District, an increase in cocaine seizures, which may indicate greater demand for the drug and, specially, changes in the cocaine purity and cutting agents profiling showing how traffickers tried to minimize difficulties in crossing the Brazilian border during COVID-19 restrictions. The information is relevant since Brazil is one of the major departure points for traded cocaine to the world. Bibliometric analysis showed that Irgafos 168 and Irganox 1076 were consistently identified as cocaine cutting agents for the first time.

Quality indicators in prolonged hemodialysis with regional citrate anticoagulation with the genius system: retrospective cohort of critical patients with acute kidney injury.

BACKGROUND: Prolonged hemodialysis (HD) is performed from 6 to 12 h and can last up to 24 h. To prevent system clotting some studies suggest that Regional Citrate Anticoagulation (RCA) use reduces bleeding rates relative to systemic heparin. However, there may be difficulties in the patient's clinical management and completing the prescribed HD with Genius system using RCA. OBJECTIVE: To analyze safety Quality Indicators (IQs) and follow up on prolonged HD with 4% sodium citrate solution in a Genius® hybrid system. METHODS: This is a retrospective cohort conducted in an intensive care unit. RESULTS: 53 random sessions of prolonged HD with 4% sodium citrate solution of critically ill patients with AKI assessed. Evaluated safety indicators were dysnatremia and metabolic alkalosis, observed in 15% and 9.4% of the sessions, respectively. Indicators of effectiveness were system clotting which occurred in 17.3%, and the minimum completion of the prescribed HD time, which was 75.5%. CONCLUSION: The assessment of the indicators showed that the use of RCA with a 4% sodium citrate solution in prolonged HD with the Genius system in critically ill patients with AKI can be performed in a simple, safe, and effective way.

Autophagy signaling in hypertrophied muscles of diabetic and control rats.

Autophagy plays a vital role in cell homeostasis by eliminating nonfunctional components and promoting cell survival. Here, we examined the levels of autophagy signaling proteins after 7 days of overload hypertrophy in the extensor digitorum longus (EDL) and soleus muscles of control and diabetic rats. We compared control and 3-day streptozotocin-induced diabetic rats, an experimental model for type 1 diabetes mellitus (T1DM). EDL muscles showed increased levels of basal autophagy signaling proteins. The diabetic state did not affect the extent of overload-induced hypertrophy or the levels of autophagy signaling proteins (p-ULK1, Beclin-1, Atg5, Atg12-5, Atg7, Atg3, LC3-I and II, and p62) in either muscle. The p-ULK-1, Beclin-1, and p62 protein expression levels were higher in the EDL muscle than in the soleus before the hypertrophic stimulus. On the contrary, the soleus muscle exhibited increased autophagic signaling after overload-induced hypertrophy, with increases in Beclin-1, Atg5, Atg12-5, Atg7, Atg3, and LC3-I expression in the control and diabetic groups, in addition to p-ULK-1 in the control groups. After hypertrophy, Beclin-1 and Atg5 levels increased in the EDL muscle of both groups, while p-ULK1 and LC3-I increased in the control group. In conclusion, the baseline EDL muscle exhibited higher autophagy than the soleus muscle. Although TDM1 promotes skeletal muscle mass loss and strength reduction, it did not significantly alter the extent of overload-induced hypertrophy and autophagy signaling proteins in EDL and soleus muscles, with the two groups exhibiting different patterns of autophagy activation.

Evaluation of kernel low-rank compressed sensing in preclinical diffusion magnetic resonance imaging.

Compressed sensing (CS) is widely used to accelerate clinical diffusion MRI acquisitions, but it is not widely used in preclinical settings yet. In this study, we optimized and compared several CS reconstruction methods for diffusion imaging. Different undersampling patterns and two reconstruction approaches were evaluated: conventional CS, based on Berkeley Advanced Reconstruction Toolbox (BART-CS) toolbox, and a new kernel low-rank (KLR)-CS, based on kernel principal component analysis and low-resolution-phase (LRP) maps. 3D CS acquisitions were performed at 9.4T using a 4-element cryocoil on mice (wild type and a MAP6 knockout). Comparison metrics were error and structural similarity index measure (SSIM) on fractional anisotropy (FA) and mean diffusivity (MD), as well as reconstructions of the anterior commissure and fornix. Acceleration factors (AF) up to 6 were considered. In the case of retrospective undersampling, the proposed KLR-CS outperformed BART-CS up to AF = 6 for FA and MD maps and tractography. For instance, for AF = 4, the maximum errors were, respectively, 8.0% for BART-CS and 4.9% for KLR-CS, considering both FA and MD in the corpus callosum. Regarding undersampled acquisitions, these maximum errors became, respectively, 10.5% for BART-CS and 7.0% for KLR-CS. This difference between simulations and acquisitions arose mainly from repetition noise, but also from differences in resonance frequency drift, signal-to-noise ratio, and in reconstruction noise. Despite this increased error, fully sampled and AF = 2 yielded comparable results for FA, MD and tractography, and AF = 4 showed minor faults. Altogether, KLR-CS based on LRP maps seems a robust approach to accelerate preclinical diffusion MRI and thereby limit the effect of the frequency drift.

Development and validation of a method for creating incomplete vertical root fracture in extracted teeth.

The present study reported a method for inducing incomplete root fracture in human extracted teeth for the purpose of evaluating the merits of different diagnostic imaging techniques. Thirty-five single-rooted teeth were inspected under magnification and transillumination to exclude previously fractured teeth. Tooth crowns were removed, and the root canals were prepared up to the ProTaper Next X4 (40.06) file. Each root was lined with wax and embedded in a polystyrene resin block. The setup was attached to a universal testing machine for pressing a customized conical wedge (diameter at tip: 0.6 mm; taper: 0.2 mm/mm) into the instrumented canal with a 2 kN load at 5 mm/min. The machine was programmed to stop after a sudden 10% drop in loading force. Each specimen was removed from the resin block and inspected under × 20 magnification and transillumination to identify the fracture characteristics (pattern, surfaces and root-third affected). The gap width of each specimen was measured at different locations along the fracture line. The protocol induced incomplete vertical root fractures in all specimens. Fracture widths were < 100 µm in all specimens (mean gap width: 34.9 µm). The proposed methodology was successful in inducing incomplete vertical root fractures with characteristics that resemble the clinical presentation of these conditions. The method is easy to execute, highly reproducible and helps to minimize bias in laboratory studies that aims to mimic vertical root fractures.

The Acute Effect of In Natura Beetroot Juice Intake on Intra-Session Exercise Sequences During Concurrent Training.

The purpose of this study was to analyze the acute effects of in natura beetroot juice intake on intra-session exercise sequences during concurrent training. Following a randomized double-blind placebo-controlled crossover design, 20 well-trained men (21.4 ± 2.9 years; 74.8 ± 6.3 kg; 175.7 ± 5.0 cm) performed two concurrent training sessions with different intra-session exercise sequences: CT1 (aerobic exercise + resistance exercises) and CT2 (resistance exercises + aerobic exercise). The resistance exercises were bench-press, lat-pull down, and shoulder-press (three sets to failure; 2 s cadence for the concentric and eccentric phases; 90 s rest interval between sets and exercises; 75% 1RM), and the aerobic exercise was 4-km running. Each concurrent training session was randomized to placebo, beetroot juice, and control (no substances), totaling six exercise sessions. The rate of perceived exertion (RPE) was reported at the end of each exercise in each session. The beetroot juice significantly increased plasma nitric oxide concentration from 14.5 ± 3.9 mmol/L to 140.2 ± 37.5 mmol/L (P < 0.01) and there was no significant change after placebo intake (13.8 ± 4.2 vs 15.1 ± 5.7 mmol/L). The 4-km running time was significantly less (P < 0.05) after beetroot juice intake in CT1 (17.0 ± 2.1 min) and CT2 (18.5 ± 1.9 min) than placebo (19.1 ± 3.2 and 22.2 ± 2.9 min, respectively) and control (19.4 ± 2.6 and 21.7 ± 3.0 min, respectively). No differences were identified in the total number of repetitions in resistance exercises and RPE. In conclusion, the acute intake of in natura beetroot juice decreased the 4-km running time independently of concurrent training exercise sequences. Our results may assist trainers in order to choose the supplement to increase performance.

Treating early postnatal circuit defect delays Huntington's disease onset and pathology in mice.

Recent evidence has shown that even mild mutations in the Huntingtin gene that are associated with late-onset Huntington's disease (HD) disrupt various aspects of human neurodevelopment. To determine whether these seemingly subtle early defects affect adult neural function, we investigated neural circuit physiology in newborn HD mice. During the first postnatal week, HD mice have less cortical layer 2/3 excitatory synaptic activity than wild-type mice, express fewer glutamatergic receptors, and show sensorimotor deficits. The circuit self-normalizes in the second postnatal week but the mice nonetheless develop HD. Pharmacologically enhancing glutamatergic transmission during the neonatal period, however, rescues these deficits and preserves sensorimotor function, cognition, and spine and synapse density as well as brain region volume in HD adult mice.

Prevalence of HPV genotypes and assessment of their clinical relevance in laryngeal squamous cell carcinoma in a northeastern state of Brazil-a retrospective study.

Background: A high prevalence and incidence of head and neck tumors make Brazil the country with the third-highest number of cases of these malignant neoplasms. The main risk factors are smoking and alcohol consumption; however, cases related to the human papillomavirus (HPV) have tripled in number, demonstrating a changing disease profile. Studies have reported the prevalence of HPV in laryngeal squamous cell carcinoma (LSCC) to vary between 8% and 83%. The role of HPV as an important causative factor in LSCC remains unclear. Methods: This retrospective study included 82 patients with LSCC diagnosed between 2014 and 2019 at two oncology hospitals in São Luís, Brazil. Sociodemographic and clinical data, and the histopathologic characteristics of the tumors, were collected directly from medical records. Genetic material was extracted from paraffin-embedded samples using nested polymerase chain reaction (PCR) and automated sequencing for HPV detection and genotyping. The results by social and clinicopathologic variables were then compared using the chi-squared test and multivariate analysis. Results: Sociodemographic analysesdemonstrated that most patients were men (87.8%), brown-skinned (75.6%), and resident in the state capital (53.7%). They generally had a poor education status (53.7%), having only an elementary school education (completed/incomplete), and 51.2% were self-employed in occupations such as farming or fishing. Smoking and alcohol consumption habits were observed in approximately half the patients. With respect to clinical characteristics, 39% of patients exhibited T1/T2 staging, 51.2% had no distant metastasis, and 30.5% had lymph node invasion. HPV DNA was detected in half the samples (50%), with the high oncogenic type 16 being the most prevalent. There was no significant relationship observed between the economic, educational, occupational with the HPV LSCC in the presented data, although multivariate analysis demonstrated that HPV DNA was more likely to be present in T3-T4 tumors (p = 0.002).

Psychoactive substances use before suicide: detailed analysis of all cases that occurred in the Brazilian Federal District in a 10-years period.

BACKGROUND: Psychoactive substances (PASs) are an important risk factor for suicide. This study investigated the sociodemographic characteristics, data related to the suicidal behavior, the methods employed, the circumstances of the events, and the use of PASs before dying in all suicides that occurred between 2005-2014 in the Brazilian Federal District, comparing cases with positive and negative detection for PASs in the post-mortem analysis to identify groups at greatest risk. METHODS: A population-based, observational, cross-sectional study with an analytical aspect was conducted with suicides cases collected from local police, which toxicological examination was performed (headspace gas chromatographic-mass spectrometry-HS-GC/MS) for detection of ethanol and methanol in blood samples; immunoassay for other substances (cocaine, marijuana, benzodiazepine). RESULTS: The results showed that the increase in the suicide rate was 10 × greater than the population growth, and 44% of the individuals used PASs before suicide. Individuals are more likely to die by suicide at home, be male, have tried before, and change their behavior days before death; they choose to hang as the method and are influenced by alcohol. CONCLUSION: Identifying what sociodemographic characteristics are associated with a fatal suicide attempt among individuals who use PASs and those who do not use and those who have/do not have mental disorders and what methods are employed could be employed as a path to better interventions. Thus, prevention actions could be planned and directed to individuals with greater risk.

Sebaceous breast carcinoma.

Breast sebaceous carcinoma is one of the rarest breast neoplasms, with less than 30 cases reported worldwide. Due to the rarity, the new WHO classification of breast tumors grouped these tumors among the ductal carcinoma. A detailed description of these cases is relevant due to the insufficient knowledge about the prognosis of this neoplasm. We report the clinical, histological, and immunohistochemical characteristics of a case of sebaceous carcinoma of the breast in an 81-year-old woman with a right breast nodule. The tumor was composed of nests of a varying mixture of sebaceous cells with abundant slightly vacuolated cytoplasm, surrounded by smaller oval-to-fusiform cells with eosinophilic cytoplasm without vacuolization. No lymph node metastases were present. The immunohistochemical reactions were positive for GATA3, EMA, CD15, and GCDFP15 (focal staining), and negative for RE, RP, and HER-2. The tumor was classified as triple-negative. Morphologically, the differential diagnoses included skin sebaceous carcinoma, lipid-rich carcinoma, apocrine carcinoma, and glycogen-rich clear cell carcinoma. Most of the previously reported cases were positive for RE and RP, which generally was associated with a better prognosis. However, some cases presented a more aggressive behavior with distant and lymph node metastases.

Scott test associated with multivariate image analysis: A more selective alternative for cocaine research in forensic laboratories.

Scott test is a simple, rapid, and low-cost preliminary test used extensively to suggest the presence of cocaine in drug seizures due to the development of a blue color. However, the presence of cutting agents can compromise the test result and may suggest the presence of cocaine when the drug is absent. This study evaluated the frequency of these results and the spectral behavior and color development of false positive substances. Furthermore, this study proposes the application of the partial least squares discriminant analysis (PLS-DA) method associated with photographic images obtained by a smartphone camera to increase the selectivity of the Scott test. For the first time, a study considered a diverse set of 173 samples, 126 of them from police drug seizures. The multivariate model presented a 100% hit rate for both the set of training samples and the test set. Thus, zero false positive (classified as positive in the absence of cocaine) and false negative (negative in the presence of cocaine) rates were achieved. Therefore, the proposed methodological alternative is promising, simple, low-cost, portable, and considerably increases the assertiveness of the preliminary test for researching cocaine.

VPS35 deficiency in the embryonic cortex leads to prenatal cell loss and abnormal development of axonal connectivity.

VPS35 is a core component of the retromer complex involved in familial forms of neurodegenerative diseases such as Parkinson's and Alzheimer's disease. In mice, VPS35 is expressed during early brain development. However, previous studies have reported that VPS35 activity is largely dispensable for normal neuronal development and initial elaboration of axonal projections. Here, we evaluated the role of VPS35 in the mouse embryonic brain using two Cre-driver lines that remove Vps35 from the cortex at different prenatal stages. We found that Vps35 mutant mice displayed microcephaly and decreased cortical thickness from the embryonic stages to adulthood. VPS35 also regulates cortical development by affecting a subpopulation of neural progenitor cells and the survival of postmitotic neurons. In addition, we showed that a lack of VPS35 leads to hypoplasia and misrouting of several axonal projections, including the anterior commissure and fornix. Furthermore, VPS35 deficiency impairs the non-autonomous development of thalamocortical axons (TCAs), which show severe disruption of innervation and terminal arborization in the cortex. Together, these data demonstrate that VPS35 plays a greater role in embryonic development of the mammalian brain than it was previously thought.

Risk or benefit? Side effects of caffeine supplementation in sport: a systematic review.

PURPOSE: The aim of this study was to systematically review evidence on the prevalence and magnitude of side effects associated with caffeine supplementation in athletes. METHODS: Systematic searches through the PubMed, VHL, Scopus, and Web of Science databases were conducted according to the PRISMA guidelines. Peer-reviewed articles written in English that reported the prevalence/percentage or magnitude/effect size of side effects after caffeine supplementation in athletes in a sports context were included. Studies were grouped by the dose of caffeine administered as follows: low = ≤ 3.0 mg/kg; moderate = from 3.1 to 6.0 mg/kg; high = ≥ 6.1 mg/kg. The magnitude of the side effects was calculated with effect sizes. RESULTS: The search retrieved 25 studies that met the inclusion/exclusion criteria with a pooled sample of 421 participants. The supplementation with caffeine produced a higher prevalence or magnitude of all side effects under investigation when compared to placebo/control situations. The prevalence (magnitude) was between 6 and 34% (ES between 0.13 and 1.11) for low doses of caffeine, between 0 and 34% (ES between -0.13 and 1.20) for moderate doses of caffeine, and between 8 and 83% (ES between 0.04 and 1.52) with high doses of caffeine. The presence of tachycardia/heart palpitations and the negative effects on sleep onset had the highest prevalence and magnitude, in athletes using supplementation with caffeine. CONCLUSION: In summary, caffeine supplementation in the doses habitually used to enhance physical performance produces several side effects, both after exercise and at least 24 h after the ingestion. However, the prevalence and magnitude of side effects with high doses of caffeine were habitually higher than with low doses of caffeine. From a practical perspective, using ~3.0 mg/kg of caffeine may be the dose of choice to obtain the ergogenic benefits of caffeine with the lowest prevalence and magnitude of side effects.

Freezing and Thawing Resistance of Fine Recycled Concrete Aggregate (FRCA) Mixtures Designed with Distinct Techniques.

The pressure to use sustainable materials and adopt practices reducing the carbon footprint of the construction industry has risen. Such materials include recycled concrete aggregates (RCA) made from waste concrete. However, concrete made with RCA often presents poor fresh and hardened properties along with a decrease in its durability performance, especially when using its fine fraction (i.e., FRCA). Most studies involving FRCA use direct replacement methods (DRM) to proportion concrete although other techniques are available such as the Equivalent Volume (EV) and Particle Packing Models (PPMs); yet their impact on the durability performance, especially its performance against freezing and thawing (F/T), remains unknown. This work, therefore, appraises the F/T resistance of FRCA mixtures proportioned through various mix proportioning techniques (i.e., DRM, EV and PPMs), produced with distinct crushing processes (i.e., crusher's fines vs. finely ground). The results show that the mix design technique has a significant influence on the FRCA mixture's F/T resistance where PPM-proportioned mixtures demonstrate the best overall performance, exceeding the specified requirements while DRM-proportioned mixtures failed F/T resistance requirements. Moreover, the crushing process plays an important role in the recycled mixtures' cracking behavior under F/T cycles, where less processing leads to fewer cracks while remaining the most sustainable option overall.

Influence of the Mix Proportion and Aggregate Features on the Performance of Eco-Efficient Fine Recycled Concrete Aggregate Mixtures.

Most of the previous research on recycled concrete aggregates (RCA) has focused on coarse RCA (CRCA), while much less has been accomplished on the use of fine RCA particles (FRCA). Furthermore, most RCA research disregards its unique microstructure, and thus the inferior performance of concrete incorporating RCA is often reported in the fresh and hardened states. To improve the overall behaviour of RCA concrete advanced mix design techniques such as equivalent volume (EV) or particle packing models (PPMs) may be used. However, the efficiency of these procedures to proportion eco-efficient FRCA concrete still requires further investigation. This work evaluates the overall fresh (i.e., slump and rheological characterization) and hardened states (i.e., non-destructive tests, compressive strength and microscopy) performance of sustainable FRCA mixtures proportioned through distinct techniques (i.e., direct replacement, EV and PPMs) and incorporating different types of aggregates (i.e., natural and manufactured sand) and manufacturing processes (i.e., crusher fines and fully ground). Results demonstrate that the aggregate type and crushing process may influence the FRCA particles' features. Yet, the use of advanced mix design techniques, particularly PPMs, may provide FRCA mixes with quite suitable performance in the fresh (i.e., 49% lower yield stress) and hardened states (i.e., 53% higher compressive strength) along with a low carbon footprint.