Initial Minutes Research Articles

Contrast of Early Phase Amyloid PET

AbstractBackgroundThe method of obtaining pseudo‐cerebral blood flow images from the initial minutes of amyloid PET scans has been proposed. This technique proves to be highly valuable as it not only indicates the presence of amyloid accumulation but also reveals sites of neurodegeneration. However, the obtained early images represent the K1 image rather than cerebral blood flow. Consequently, the contrast in early images from amyloid PET tracers is thought to be compromised when compared to cerebral blood flow images.MethodTo enhance the contrast in early images obtained from amyloid PET tracers and thereby improve diagnostic accuracy, we developed a method for contrast recovery and established a methodology for determining the parameter involved in achieving this contrast recovery, drawing insights from a thorough literature review. Additionally, we conducted a comparative analysis involving PiB’s early images and FDG, investigating their respective contributions.ResultOur study demonstrated a strong correlation between FDG and early images of PiB, with relatively inconspicuous underestimations in high‐blood‐flow regions.ConclusionWhile we theoretically established a method to recover the contrast in early images, our findings suggest that amyloid PET tracers may exhibit a higher permeability‐surface area product than anticipated. This observation raises the possibility that, without correction, these tracers might inherently provide sufficient contrast.

Evolution of CO2 Uptake Degree of Ordinary Portland Cement During Accelerated Aqueous Mineralisation

The utilisation of carbonation treatments to produce building materials is emerging as a valuable strategy to reduce CO2 emissions in the construction sector. It is of great importance to regulate the degree of carbonation when the mineralisation process is combined with hydration, as a high CO2 uptake may impede the development of adequate strength. A significant number of studies focus on attaining the maximum carbonation degree, with minimal attention paid to the examination of the evolution of CO2 uptake over the initial stages of the process. In this context, the present study aims to investigate the evolution of CO2 uptake over time during carbonation. Ordinary Portland Cement (OPC) is employed as material, with aqueous carbonation selected as the mineralisation process. This investigation encompasses a range of carbonation durations, spanning from 5 to 40 min. The analysis of the evolution of the mineral composition with time demonstrated that the rate of the carbonation reaction accelerates in the initial minutes, resulting in the conversion of all the portlandite produced during the hydration process in the initial 10 min. Quantitative analysis of the carbonation degree indicated that the CO2 uptake at 40 min is equal to 19.1%, which is estimated to be approximately 70% of the maximum achievable value. By contributing to the understanding of the early carbonation mechanisms in aqueous conditions of OPC, this study provides valuable support for further investigation focused on the use of cement mineralisation processes to produce building materials.

Propofol and Fentanyl Pharmacokinetics and Pharmacodynamics in Extracorporeal Membrane Oxygenation.

Despite the potential risks associated with sedation, there is a paucity of pharmacokinetic/pharmacodynamic (PK/PD) data for propofol and fentanyl in patients supported with veno-venous extracorporeal membrane oxygenation (V-V ECMO). Describe propofol and fentanyl PK/PD profiles in V-V ECMO patients. Prospective, single-center, open-label PK/PD study at the Toronto General Hospital ICU between July 2022 and January 2023. Using high-performance liquid chromatography-tandem mass spectrometry, propofol and fentanyl total concentrations were measured during V-V ECMO. Sequential PK/PD modeling, using sex as a covariate, was conducted with processed electroencephalography (PSI) for sedation, and expiratory occlusion pressure (Pocc), and airway occlusion pressure during the first 0.1 seconds (P0.1) for respiratory effort. Eleven patients underwent 106 evaluations over a median (IQR) follow-up of 146 (116-146) hours. Patient's average (±SD) age was 43 (±13) years, and 55% were female. Propofol and fentanyl PK were best described by a two-compartment model. Propofol-PSI PD was described using an effect compartment, with a coefficient of determination (ρ2) of 0.78. There was a significant increase in propofol (p=0.01) and fentanyl (p=0.03) clearance within 10 minutes of ECMO initiation, plateauing after 8 hours of ECMO support. Despite this, patient over-sedation (PSI<40) occurred in 74% of the observations. Females exhibited higher sedative central volume of distribution and lower propofol clearance. ECMO initiation resulted in a time-limited increased sedative clearance. PSI accurately described sedative PD, but variable respiratory effort was observed irrespective of sedative plasma concentrations. Sex-based differences were found in sedative PK/PD parameters.

Under pressure: Effects of distraction and reappraisal on adolescents' psychophysiological stress responses

Although cognitive reappraisal and distraction are generally both beneficial to down-regulate negative affect, it remains unknown whether one may be more effective in helping adolescents handle stressful situations. Therefore, this study compared the effects of both strategies on adolescent's psychophysiological stress responses. Belgian adolescents (N = 82, Mage = 13.99 years, SDage = 0.62; 38% males) received a 100-min training on cognitive reappraisal or distraction to ensure adolescents could use the strategies when instructed; subsequently they were exposed to a standardized interpersonal stressor after which they were instructed to use the learned technique. As compared to participants in the cognitive reappraisal condition, participants in the distraction condition reported larger increases in positive affect during the initial minutes of stress recovery. However, no clear differences emerged when examining negative affect and respiratory sinus arrythmia recovery. These findings provide new insights into the effectiveness of cognitive reappraisal and distraction in adolescents.

Timing of onset of intraoperative transfusion anaphylaxis: a literature review.

Clinical diagnosis of intraoperative transfusion anaphylaxis using clinical symptoms is challenging and should be made carefully, as an incorrect clinical diagnosis can exacerbate surgical bleeding secondary to stopping a clinically indicated blood transfusion. The timing of onset of anaphylaxis to start of transfusion may be the key to correctly diagnosing intraoperative transfusion anaphylaxis clinically. However, the reliability of this measure remains unknown. A literature search was conducted using MEDLINE, Embase, the Cochrane Database of Systematic Reviews, and the Cochrane Central Register of Controlled Trials up to June 29, 2021. No language restriction was applied. Two pairs of review authors independently reviewed intraoperative transfusion anaphylaxis cases and extracted data on the timing of onset of anaphylaxis to start of transfusion. A total of 8,918 articles were reviewed, the full texts of 186 articles were assessed, and 20 intraoperative transfusion anaphylaxis cases were included in this study. The 20 intraoperative transfusion anaphylaxis cases included a precise timing of onset. With nine cases, cardiovascular surgery was the most prevalent, and one case was fatal. Fifteen cases had a timing of onset in minutes, and of those, 14 reported timeframes within 30 minutes of initiation of transfusion (median: 15.5, 5-30 minutes). Almost all cases of intraoperative transfusion anaphylaxis occurred within 30 minutes of the transfusion initiation. This timeframe may be helpful in the clinical diagnosis of intraoperative transfusion anaphylaxis.

Code-ICH: A New Paradigm for Emergency Intervention.

Intracerebral hemorrhage (ICH) is the most devastating type of stroke, causing widespread disability and mortality. Unfortunately, the acute care of ICH has lagged behind that of ischemic stroke. There is an increasing body of evidence supporting the importance of early interventions including aggressive control of blood pressure and reversal of anticoagulation in the initial minutes to hours of presentation. This review highlights scientific evidence behind a new paradigm to care for these patients called Code-ICH. While numerous trials aimed at decreasing hematoma expansion through single interventions had failed to show statistically significant effects on primary outcomes, time-sensitive, multifaceted, bundled care approaches have recently shown substantial promise in improving functional outcomes in patients with ICH. The concept of Code-ICH can serve as a structural platform for the practice of acute care neurology to continuously measure its performance, reflect on best practices, advance care, and address disparities.

Cord Blood pH and Lactate- A Step Ahead in Diagnosis of Fetal Acidaemia in Patients with Abnormal Cardiotocography

OBJECTIVES: Electronic fetal monitoring (EFM) is used to identify early signs of fetal deterioration. However, caution is advised when interpreting cardiotocographic parameters. A promising alternative is umbilical cord blood sampling. The analysis of blood gases and lactate levels in the cord within the ini-tial minutes of life is a recommended approach. STUDY DESIGN: This prospective cohort study, conducted over eighteen months from June 2021 to December 2022, enrolled 70 patients with non-reactive and 70 with reactive cardiotocograph (CTG) pat-terns. APGAR scores were recorded at 1 and 5-minute intervals. 1 ml of umbilical artery blood was as-sessed in an arterial blood gas machine and fetal acidosis was defined as pH &lt;7.0 and a lactate con-centration exceeding 4 mmol/L. RESULTS: In the non-reactive CTG group, 35.7% had early decelerations, 37.1% had variable decel-erations, and 17.1% had late decelerations (p&lt;0.001). The mean cord blood lactate was 5.220±1.970 mmol/L in the non-reactive CTG group and 3.400±0.228 mmol/L in the reactive CTG group. Similarly, the mean cord blood pH was 7.030±0.007 in the non-reactive CTG group and 7.170±0.076 in the reac-tive CTG group (p&lt;0.001). 14.3% of cases in the non-reactive CTG group had a 5-minute APGAR &lt;7, with a higher APGAR score in the reactive group. CONCLUSION: The study suggests that abnormal or indeterminate CTG readings are linked to a higher risk of intrapartum fetal acidosis. Non-reactive CTG results were associated with higher mean cord blood lactate and pH levels and more number of Neonatal Intensive Care Unit (NICU) admissions. There is a definite correlation between abnormal CTG patterns and poorer neonatal outcomes.

Synthesis of Activated Biochar from the Bark of Moringa oleifera for Adsorption of the Drug Metronidazole Present in Aqueous Medium

Moringa oleifera seeds, in particular, have been used for water and wastewater treatment due to their ability to remove many pollutants. Therefore, the present work aims to produce bioadsorbent materials by pyrolysis using biomass from the seed shell of Moringa oleifera to remove the drug Metronidazole present in an aqueous medium. The biochars produced were activated with phosphoric acid (H3PO4) and potassium hydroxide (KOH) to compare the material’s modifications and adsorption mechanisms with the biochar in nature (BCM). The biochars were characterized by Point-of-zero charges (pHpzc), Scanning Electron Microscopy (SEM), X-ray Diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), and Raman spectroscopy. The studies showed that the adsorption behavior varied with the pH of the solution. The adsorption study verified that the activated biochars presented better results, so in the kinetic study, the adsorption behavior occurred rapidly in the initial minutes until stabilizing within 3–4 h, better fitting the Elovich model. Isotherm models were tested, where the experimental data were adjusted to the Sips model, with an adsorption capacity of 18 mg g−1 for acid-activated biochar (BCH3PO4) and KOH-activated biochar (BCKOH) with 366.49 mg g−1. The results showed that biochars, especially BCKOH, become viable for production because they are a low-cost material and highly effective in removing drugs.

Optimal duration and timing of basic-life-support-only intervention for patients with out-of-hospital cardiac arrest

To elucidate the relationship between the interval from cardiopulmonary resuscitation initiation to return of spontaneous circulation (ROSC) and neurologically favourable 1-month survival in order to determine the appropriate duration of basic life support (BLS) without advanced interventions. This population-based cohort study included patients aged ≥ 18 years with 9132 out-of-hospital cardiac arrest of presumed cardiac origin who were bystander-witnessed and had achieved ROSC between 2018 and 2020. Patients were classified into two groups based on the resuscitation methods as the “BLS-only” and the “BLS with administered epinephrine (BLS-AE)” groups. Receiver operating characteristic (ROC) curve analysis indicated that administering BLS for 9 min yielded the best neurologically outcome for patients with a shockable rhythm [sensitivity, 0.42; specificity, 0.27; area under the ROC curve (AUC), 0.60] in the BLS-only group. Contrastingly, for patients with a non-shockable rhythm, performing BLS for 6 min yielded the best neurologically outcome (sensitivity, 0.65; specificity, 0.43; AUC, 0.63). After propensity score matching, multivariate analysis revealed that BLS-only resuscitation [6.44 (5.34–7.77)] was associated with neurologically favourable 1-month survival. This retrospective study revealed that BLS-only intervention had a significant impact in the initial minutes following CPR initiation. Nevertheless, its effectiveness markedly declined thereafter. The optimal duration for effective BLS-only intervention varied depending on the patient's initial rhythm. Consequently, advanced interventions should be administered within the first few minutes to counteract the diminishing effectiveness of BLS-only intervention.

Effect of Tempering Time on the Microstructure and Properties of Martensitic Stainless Steel

Martensitic stainless steels (MSSs) have been widely used in the manufacture of turbine blades, surgical instruments, and cutting tools because of their hardness and corrosion resistance. The MSSs are usually tempered at a temperature no higher than 250 °C after quenching to avoid the decline in the hardness, strength, and corrosion resistance of the steels. However, some short-time thermal shocks are inevitable in processes like welding, water grinding, laser marking, etc., in the manufacturing of kitchen knives, all of which may have negative effects on the mechanical properties and corrosion resistance. The effects of these short-time thermal shocks have rarely been studied. In this paper, the martensitic stainless steel 5Cr15MoV (X50CrMoV15 is European Standards) was selected to be tempered at the sensitization temperatures (480 to 600 °C) for a series of times (0.5 to 128 min) after quenching, and the microstructures, hardness, and corrosion resistance of the steel after tempering were investigated. It was shown that the variation in hardness and corrosion resistance of the 5Cr15MoV steel could be divided into four stages over time during tempering at the sensitization temperatures. The hardness of steel was found to increase at first and then decrease with time; accordingly, good corrosion resistance was retained in the initial few minutes of tempering, which then deteriorated fast. The variation in hardness and corrosion resistance of the 5Cr15MoV steel is related to the diffusion of C and Cr atoms at different tempering temperatures. The mechanism of the mechanical properties and corrosion resistance variation caused by the diffusion of C and Cr atoms during tempering at the sensitization temperatures was also discussed.

Early Physician Gestalt Versus Usual Screening Tools for the Prediction of Sepsis in Critically Ill Emergency Patients

ObjectiveCompare physician gestalt to existing screening tools for the identification of sepsis in the initial minutes of presentation when time sensitive treatments must be initiated. MethodsThis prospective observational study conducted with consecutive encounter sampling took place in the emergency department of an academic, urban, safety net hospital between September 2020 and May 2022. The study population included critically ill emergency department patients excluding traumas, transfers, and self-evident diagnoses. Emergency physician gestalt was measured using a visual analog scale (VAS) from 0-100 at 15 and 60 minutes after patient arrival. The primary outcome was an explicit sepsis hospital discharge diagnosis. Clinical data were recorded up to 3 hours to compare Systemic Inflammatory Response Syndrome (SIRS), Sequential Organ Failure Assessment (SOFA), quick SOFA (qSOFA), Modified Early Warning Score (MEWS) and a logistic regression machine learning model utilizing Least Absolute Shrinkage and Selection Operator (LASSO) for variable selection. The screening tools were compared utilizing ROC analysis and calculation of AUC. Results2,484 patient-physician encounters involving 59 attending physicians were analyzed. 275 patients (11%) received an explicit sepsis discharge diagnosis. When limited to available data at 15 minutes, initial VAS (AUC 0.90; 95% CI 0.88-0.92) outperformed all tools including LASSO (0.84, 95% CI 0.82-0.87), qSOFA (0.67; 95% CI 0.64-0.71), SIRS (0.67; 95% 0.64-0.70), SOFA (0.67; 95% CI 0.63-0.70) and MEWS (0.66; 95% CI 0.64-0.69). Expanding to data available at 60 minutes did not meaningfully change results. ConclusionsAmong adults presenting to an emergency department with an undifferentiated critical illness, physician gestalt in the first 15 minutes of the encounter outperformed other screening methods in identifying sepsis.

In-vivo evaluation of the effects of short-term dehydration and rehydration on the color differences of immature permanent incisor teeth.

It is aimed to evaluate the color changes of upper central incisor teeth with different root maturation levels after 15 min of dehydration and rehydration. Using the Cvek classification, 60 participants were divided into five groups. A spectrophotometer, equipped with a specially designed jig, was utilized for color measurements. Following isolation, color measurements were conducted at the dehydration process intervals of baseline, 1st, 2nd, 3rd, 5th, 7th, 10th, and 15th minutes. After mouth rinsing, measurements were repeated at the same time intervals during the rehydration process. CIEDE2000 (ΔE00) values and the Whiteness Index (WID) were obtained to compare the color changes between the initial readings and each interval. Friedman and Repeated Measures ANOVA were applied to compare classes by time during the dehydration and rehydration periods, as well as ANOVA and Kruskal-Wallis tests to compare by classes for each time (p < 0.05). Significant differences emerged in the mean ΔE00 values during dehydration and rehydration periods across all Cvek Classes (p < 0.05). While no statistically significant differences were observed among Classes at different minutes during the rehydration period (p > 0.05), it was particularly noted that the mean ΔE00 values of Classes 2, 3, and 5 at the 2nd minute of dehydration were statistically significantly higher than the mean of Class 1 (p < 0.05). However, when evaluating the starting and ending measurements of both dehydration and rehydration processes, and the overall change in ΔE00 and ΔWID, no significant variations were detected across the Classes (p > 0.05). In teeth that have just erupted and are still undergoing root development, dehydration in the initial minutes results in noticeable color changes. However, the change in ΔE00 and ΔWID of the teeth was found to be similar after the dehydration and rehydration processes. According to the Cvek classification, the lower color change in Class 1 teeth within the first 2 min of dehydration and the need for more than 15 min of rehydration for immature teeth with an open apex to return to their initial state after a 15-min dehydration are crucial for clinicians in terms of color assessment timing.

Gastric Perforation, a Rare Consequence of Unintentional Esophageal Intubation

Accidental esophageal intubation is a preventable human error that complicates airway management and continues to occur despite advances in medical devices. Perforation of the stomach has been associated with esophageal intubation in several case reports. This report presents a case of an elderly woman suspected of having COVID-19-related pneumonia. She was intubated due to respiratory dysfunction. In the initial few minutes, the patient became desaturated, leading to a second intubation. An hour later, the patient’s abdomen was distended, and the chest computed tomography (CT) showed a massive pneumoperitoneum. During laparotomy, a 6 cm long rupture was found in the lesser curvature, which was attributed to accidental esophageal intubation. To avoid such a fatal condition, it is imperative for physicians to ensure the correct positioning of the endotracheal tube. To achieve this goal, further investigation into readily available and highl y sensitive techniques is recommended.

A Ramp versus Step Transition to Constant Work Rate Exercise Decreases Steady-State Oxygen Uptake.

This study aimed to investigate whether a ramp-to-constant WR (rCWR) transition compared with a square-wave-to-constant WR (CWR) transition within the heavy-intensity domain can reduce metabolic instability and decrease the oxygen cost of exercise. Fourteen individuals performed (i) a ramp-incremental test to task failure, (ii) a 21-min CWR within the heavy-intensity domain, and (iii) an rCWR to the same WR. Oxygen uptake (V̇O 2 ), lactate concentration ([La - ]), and muscle oxygen saturation (SmO 2 ) were measured. V̇O 2 and V̇O 2 gain (V̇O 2 -G) during the first 10-min steady-state V̇O 2 were analyzed. [La - ] before, at, and after steady-state V̇O 2 and SmO 2 during the entire 21-min steady-state exercise were also examined. V̇O 2 and V̇O 2 -G during rCWR (2.49 ± 0.58 L·min -1 and 10.7 ± 0.2 mL·min -1 ·W -1 , respectively) were lower ( P < 0.001) than CWR (2.57 ± 0.60 L·min -1 and 11.3 ± 0.2 mL·min -1 ·W -1 , respectively). [La - ] before and at steady-state V̇O 2 during the rCWR condition (1.94 ± 0.60 and 3.52 ± 1.19 mM, respectively) was lower than the CWR condition (3.05 ± 0.82 and 4.15 ± 1.25 mM, respectively) ( P < 0.001). [La - ] dynamics after steady-state V̇O 2 were unstable for the rCWR ( P = 0.011). SmO 2 was unstable within the CWR condition from minutes 4 to 13 ( P < 0.05). The metabolic disruption caused by the initial minutes of square-wave exercise transitions is a primary contributor to metabolic instability, leading to an increased V̇O 2 -G compared with the rCWR condition approach. The reduced early reliance on anaerobic energy sources during the rCWR condition may be responsible for the lower V̇O 2 -G.

Prehospital emergency medicine research by additional teams on scene – Concepts and lessons learned

While the initial minutes of acute emergencies significantly influence clinical outcomes, prehospital research often receives inadequate attention due to several challenges. Retrospective chart reviews carry the risk of incomplete and inaccurate data. Furthermore, prehospital intervention trials frequently encounter difficulties related to extensive training requirements, even during the planning phase. Consequently, we have implemented prospective research concepts involving additional paramedics and physicians directly at the scene during major emergency calls. Three concepts were used: (I) Paramedic field supervisor units, (II) a paramedic + physician field supervisor unit, (III) a special physician-based research car. This paper provides insights into our historical perspective, the current situation, and the lessons learned while overcoming certain barriers and using existing and novel facilitators. Our objective is to support other research groups with our experiences in their planning of upcoming prehospital trials.

Flow and temporal effects on the sonolytic defluorination of perfluorooctane sulfonic acid

The removal of per- and polyfluoroalkyl substance (PFAS) pollution from the environment is a globally pressing issue, due to some PFAS’ recalcitrant, bioaccumulative, and carcinogenic nature. Destruction via ultrasonic waves (sonolysis) is a promising contender for industrialisation due to; moderate power consumption, applicability to several PFAS and sample types, and limited by-products. Liquid flow rate through an ultrasonic reactor can affect the size, shape, and spatial distribution of ultrasonic cavities and hence their chemical activity. Such effects have not been studied during PFAS sonolysis, and temporal effects have not been studied much beyond the reactant concentration. Here, the effects of varying recirculating flow rate on the ultrasonic defluorination of perfluorooctane sulfonic acid (PFOS) and implications for industrial scale up are presented. Under the ultrasonic power (200 W L−1, 2.27 W cm−2) and frequency (410 kHz) used, flow rates of 79 and 214 ml min−1 enhanced defluorination up to 14 % during 30 min of treatment. However, these effects were temporal and most significant in the initial minutes of treatment. This indicated a dynamic bubble size distribution which stabilised after around 15 min. Defluorination rates of PFOS were compared with measured potassium iodide dosimetry, calorimetry, sonoluminescence (SL), and sonochemiluminescence (SCL). Flow rates which enhanced defluorination correlated moderately with enhanced SCL and negatively impacted SL, calorimetry, and dosimetry. Effects were attributed to perturbed cavity surfaces, leading to asymmetric cavity collapse, and the possibility of enhanced solvated electron production/interaction. SL, SCL, dosimetry, and calorimetric measurements were also temporal, and each showed different times to equilibrate. Flow rates of 439 and 889 ml min−1 returned all sonochemical measurements to the levels without flow, likely due to continued collapse temperature quenching by furthered bubble asymmetry. Flow also enhanced reactor cooling, which is significant for industrial temperature control. The pump energy consumed was small (≈1.9 %) compared to that of the amplifier and chiller, hence, PFOS defluorination was more cost-effective using flow. However, the effect may be limited for the longer treatment times needed for environmental remediation.

Farm Crime and Security: Evaluating Smart Tag Technology for Preventing, Tracking and Recovering Stolen Livestock

This research study evaluates the efficacy of Ceres Tag, a livestock information platform that utilises a unique smart tag, in improving farm security by preventing, interrupting, and reducing livestock theft – a prevalent issue among farmers and landholders in countries like Australia. The Ceres Tag is equipped with an accelerometer and global navigation satellite system (GNSS) technology to collect data on animal health, welfare, movement, and traceability. It was hypothesised that the Ceres Tag could combat livestock theft by enabling interventions at three key stages: rapid prevention, tracking of stolen livestock, and recovery of stolen livestock. To assess this, a mock theft of livestock was staged, accompanied by a coordinated law enforcement response. Key findings include: (1) the Ceres Tag issued a ‘high activity alert’ to farmers, indicating significant livestock agitation, within 12 minutes of the mock theft initiation; (2) utilising the data, the New South Wales (NSW) Police were able to track and interrupt the livestock theft within 25 minutes; (3) the data enabled the NSW Police to repeatedly track and interrupt the theft on three separate occasions over a 110 kilometre distance and 90-minute period; and (4) following the thieves' arrival at their destination, the NSW Police, aided by the data, recovered the stolen livestock within 20 minutes. The Ceres Tag system increases the risk of criminal behaviour in often riskless rural settings, effectively ‘hardening’ livestock as targets through technological innovation. Furthermore, the platform provides farmers with tangible evidence of a crime, substantially expediting the crime reporting process. This timely reporting, coupled with the data provided by Ceres Tag, positions police for rapid and effective intervention, thereby enhancing their capacity to investigate and resolve incidents of livestock theft. Overall, the results suggest that the Ceres Tag offers a promising technological tool for farmers and law enforcement officers alike, aimed at fortifying farm security and minimizing livestock theft.

Impact of Fuzzy Tsukamoto in Controlling Room Temperature and Humidity

Dry season is a season where the room temperature exceeds the needs of the body so that it is unpleasant, unhealthy and can interfere with human productivity. In addition, the efficiency of use and resource requirements are also a concern for some people. To overcome this problem, an automatic room temperature control device was created using the ESP32 microcontroller with Tsukamoto's fuzzy algorithm optimization as a data processing technique to produce optimal fan speeds in duty cycle units based on temperature and humidity conditions in realtime. Four tests by running a fan for 30 minutes on each showed that the average difference between the maximum and minimum temperatures in the room was 0.95°C, while the average difference between maximum and minimum humidity was 2.0%. In addition, the test graph shows that when the fan is rotated in a closed room without air circulation, the relative temperature change increases from the initial minute to the last minute of the test. Meanwhile, changes in relative humidity decrease, although fluctuations increase within 1-4 minutes. This study found that fans are not effective in lowering room temperature optimally. Therefore, it is recommended to replace with an exhaust fan in future research.

Enhanced removal of Ni-EDTA by three-dimensional electro-Fenton process using Fe-N-doped biochar as catalytic particle electrodes

Heavy metal complexes pose a challenge in terms of their resistance to removal due to their stable and intricate structure. In this study, we explored the utilization of Fe and N co-doped biochar derived from rice husk (Fe-N-RHBC) as catalytic particle electrodes in a three-dimensional electro-Fenton (3D-EF) system for the decomplexation and removal of a model pollutant, Ni-EDTA. The characterization analysis and comparison of catalytic activities confirmed the beneficial effects of Fe and N co-doping on various aspects, such as the types of active sites, interfacial electron transfer properties, and H2O2 decomposition capacity. Compared to other investigated oxidation systems, the 3D-EF process demonstrated rapid removal of Ni-EDTA within the initial minute, with a maximum H2O2 utilization of 99.1% after 30 min. The prepared catalytic particle electrodes exhibited high stability and catalytic capacity even after three consecutive cycles. Throughout the reaction, several processes, including anode oxidation, particle electrode polarization, catalysis, and adsorption of Fe-N-RHBC, as well as cathodic electro-deposition, synergistically contributed to the treatment of Ni-EDTA. The surface-bound O2− radicals and 1O2 generated by the Fe-N-RHBC catalytic particle electrode played a crucial role in the decomplexation and removal of Ni-EDTA. Building upon these findings, we further proposed potential mechanisms for the removal of Ni-EDTA in the 3D-EF system using the Fe-N-RHBC catalytic particle electrode.

Microstructural effect of different concentrations of hydrogen peroxide photoactivated with LED/laser

BackgroundThe use of different concentrations of hydrogen peroxide (HP) photoactivated with LED/laser sources is common however, their influence on tooth structure is not yet fully elucidated. This study aimed to evaluate the pH, microhardness and surface roughness of different bleaching protocols photoactivated with LED/laser. MethodsForty bovine incisors were sectioned (7 × 7 × 2 mm) and randomized into four groups for analysis of pH (n = 5), microhardness and roughness (n = 10): HP35, HP6_L, HP15_L, HP35_L. The pH analysis was performed in the initial and final minute of the bleaching protocol. Microhardness and roughness were evaluated before and 7 days after the last bleaching session. Results were obtained from two-way ANOVA for repeated measures and Bonferroni post-test at a significance level of 5%. ResultsHP6_L showed higher pH and greater stability between the initial and final evaluations, while the other groups showed similar pH with reduced values in the intragroup evaluation. No differences between groups in microhardness and roughness evaluations were observed. ConclusionsAlthough HP6_L showed higher alkalinity and pH stability, none of the protocols reduced the microhardness and surface roughness of bovine enamel.