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Thermo-hydraulic efficiency of lung-inspired compact plate heat exchangers made using additive manufacturing techniques with steel, aluminum and titanium powders
No full textThe selection of material for compact plate heat exchangers (CPHEs) is of increasing importance due to global economic and supply constraints. Additionally, the influence of material selection on the thermo-hydraulic characteristics of CPHEs is an area of ongoing research. This study aims to address these issues by analyzing the thermo-hydraulic performance of CPHEs made from steel, aluminum, and titanium materials with small, complex channels. Using an additive manufacturing method (specifically Direct Metal Laser Sintering), lung-inspired CPHEs of identical geometry and roughness were manufactured from steel, aluminum and titanium powders. The thermo-hydraulic characteristics of CPHEs as well as that of a traditional one with Chevron-type, were investigated using both experimental and numerical techniques under specific operating conditions to determine the optimum between maximum heat transfer and minimum pressure drop. The findings of this study reveal that as the temperature difference between the inlet on the hot and cold sides, as well as the flow rate, were increased, there was a corresponding increase in both amount of heat transferred and loss of pressure across all investigated CPHEs. Compared to the chevron type brazed plate heat exchanger, the CPHE made from aluminum showed a 75.2 % and 11.2 % increase in heat transfer and a 31.8 % and 10.9 % reduction in pressure drop at 3 and 6 L/min, respectively, for a temperature difference of 90–40 °C. This study suggests that the use of materials with different thermal conductivities in CPHEs may offer a promising solution to achieve elevated heat transfer rates while minimizing pressure drop
Comparing the Diagnostic Performance of HFA-PEFF and H2FPEF Scoring Systems in Heart Failure with Preserved Ejection Fraction Patients: Insights from the APOLLON Registry
No full textBackground: Heart failure with preserved ejection fraction is a complex and heterogeneous clinical syndrome, poses significant diagnostic challenges. The HFA-PEFF [Heart Failure Association of ESC diagnostic algorithm, P (Pretest Assessment), E (Echocardiographic and Natriuretic Peptide score), F1 (Functional testing in Case of Uncertainty), F2 (Final Aetiology)] and H2FPEF [Heavy (BMI>30 kg/m2), Hypertensive (use of ≥2 antihypertensive medications), atrial Fibrillation (paroxysmal or persistent), Pulmonary hypertension (Doppler Echocardiographic estimated Pulmonary Artery Systolic Pressure >35 mm Hg), Elderly (age >60 years), Filling pressure (Doppler Echocardiographic E/e' >9)] scoring systems were developed to aid in diagnosing heart failure with preserved ejection fraction. This study aimed to assess the concordance and clinical accuracy of these scoring systems in the 'A comPrehensive, ObservationaL registry of heart faiLure with mildly reduced and preserved ejection fractiON' cohort.
Methods: A comPrehensive, ObservationaL registry of heart faiLure with mildly reduced and preserved ejection fractiON study was conducted as a multicenter, cross-sectional, and observational study; to evaluate a group of Heart failure with mildly reduced ejection fraction and heart failure with preserved ejection fraction patients who were seen by cardiologists in 13 participating centers across 12 cities in Türkiye.
Results: The study enrolled 819 patients with heart failure with preserved ejection fraction, with high probability heart failure with preserved ejection fraction rates of 40% and 26% for HFA-PEFF and H2FPEF scorings, respectively. The concordance between the 2 scoring systems was found to be low (Kendall's taub correlation coefficient of 0.242, P < .001). The diagnostic performance of both scoring systems was evaluated, revealing differences in their approach and ability to accurately identify heart failure with preserved ejection fraction patients.
Conclusion: The low concordance between the HFA-PEFF and H2FPEF scoring systems underscores the ongoing challenge of accurately diagnosing and managing patients with heart failure with preserved ejection fraction. Clinicians should be aware of the strengths and limitations of each scoring system and use them in conjunction with other clinical and laboratory findings to arrive at an accurate diagnosis. Future research should focus on identifying additional diagnostic factors, developing more accurate and comprehensive diagnostic algorithms, and investigating alternative methods of diagnosis or stratification of patients based on different clinical characteristics
Electrochemical Carbon Dioxide Detection
No full textIn this chapter, initially, the concerns about global warming and greenhouse effects, and the research on sensing, capturing, and monitoring carbon dioxide (CO2) have been discussed in a general manner. After that, the fundamental methods and electrodes used in the electrochemical measurements are given. Finally, the electrochemical detection and reduction of CO2 are detailed by potentiometric, amperometric, conductometric, voltametric, or coulometric sensors that can be utilized easily as directly as solid-state or electrolyte using types. The electrodes used as well as the measurement methods increase the variety of these sensors. From the Clark electrode to the present, Field Effect Transistors, Kelvin probes, oxygen probes, electronic noses, solid electrodes which are reinforced by using divergent nanomaterials, transition metal oxides, polymers, and porous solid electrodes were utilized in different gas sensing electrochemical method
Bioactive natural small molecules from mushrooms as potential source of anticancer agents
No full textRecently, drugs obtained from natural products have attracted great interest as potential therapeutic agents in cancer treatment due to their lesser side effects and low toxicity. Mushrooms are one of the natural sources containing various bioactive compounds with antioxidant, anticancer, antidiabetic, antimicrobial, hepatoprotective, antitumor, antiviral, and immunomodulatory properties. This chapter reviews the anticancer metabolites of low-molecular weight from mushroom species. Low-molecular-weight metabolites have the ability to go into the cell and affect or interfere with the biological processes therein. Research both in vivo and in vitro has reported that such compounds derived from natural sources are efficient in inhibiting cancer growth and metastasis. Low molecular weight cytotoxic molecules such as pulveraven A, roridin E, 12′-episatratoxin H, trichoverritone, astrakurkurone, inotodiol, GL22, lepiotaprocerins H, G, L, vulpinic acid, grifolin, craterellyne I, phellibarin D, trichodermol, 8-deoxytrichothecin, trichothecin, trichothecinol B, trichothecinol A, atractylenolide I, terreumol A, flammulinolides A, B, C, F, jiangxienone, aurisin A, ergosta‐7,22‐diene‐2β,3α,9α‐triol, hypoxylonols D, E, and neogrifolin have been purified from various mushroom species. In this chapter, the compounds (1–257) with anticancer activity isolated from 61 different mushroom species in the last 2 decades were evaluated. Further, triterpenoids, steroids, steroidal alcohols, phenolic compounds, sesquiterpenes, meroterpenoids, p-terphenyls, ergostanes, alkaloids, fatty acids, cerebrosides, furanones, disulfide compounds, butanolides, aromatic compounds, organic acids, benzo[j]fluoranthene derivatives and cyclopeptides indicating cytotoxic activity toward various cancer cell lines from mushrooms were reported here
Experimental investigation of full-scale reinforced concrete beams under reversed-cyclic pure torsion
No full textMany sub-assemblies of Civil Engineering structures such as columns and primary (spandrel) beams are subjected to torsion. This study aims to evaluate the torsional behavior of reinforced concrete (RC) members under reversed-cyclic pure torsional loading. An experimental program was conducted on nine full-scale specimens including the parameters such as concrete compressive strength, and transverse and longitudinal reinforcement ratios. During the tests, a new test setup was designed to allow the specimens to elongate at one end and to apply the moments at the other end along the specimen's rotational axis. Ultimate, peak and yield torques, torsional stiffness, energy dissipation capacity, and torsional bearing capacity of specimens were evaluated. In some specimens, longitudinal elongation was measured. Out of all test parameters, it has been concluded that the most important parameter on the torsional capacity of the members was the transverse reinforcement ratio. The concrete strength became a more effective factor in determining the fracture mode. Thus, the amount of longitudinal reinforcement was observed to be the parameter that mostly affected the flexibility of the elements
Association between the anthropometric measurements and dietary habits on telomere shortening in healthy older adults: A-cross-sectional study
No full textim: This study aimed to evaluate the effect of anthropometric measurements and dietary habits on telomere length in healthy older residents in rural and urban areas. Methods: This was a cross-sectional study. The study population included 81 healthy older individuals aged ≥80 years. A quantitative food frequency questionnaire was used to determine dietary habits. Anthropometric measurements were taken by researchers. The telomere length of individuals was determined from leukocytes using quantitative polymerase chain reaction. Results: Urban women had longer telomeres than rural women (P < 0.05). Rural men had significantly higher hip circumference, middle-upper arm circumference and fat-free mass than urban men (P < 0.05). It was shown that while fresh vegetable consumption was higher in rural areas, carbonated drink consumption was higher in urban areas (P < 0.05). In women, homemade bread and sugar consumption were higher in rural areas, and honey consumption was higher in urban (P < 0.05). Red meat, milk-based dessert and pastry consumption explain telomere shortening by 22.5%, 24.8% and 17.9%, respectively. In addition, the model based on anthropometric measurements also contributes to explaining telomere shortening by 42.9%. Conclusion: Red meat, milk-based dessert and pastry consumption, and waist circumference, hip circumference, waist-to-hip ratio and waist-to-height ratio are associated with telomere length. Longer telomeres are associated with a healthy, balanced, adequate diet and maintaining a healthy body weight/proportion, and they are crucial for achieving healthy aging
Classification of Parkinson’s disease with dementia using phase locking factor of event-related oscillations to visual and auditory stimuli
No full textObjective. In the last decades, machine learning approaches have been widely used to distinguish Parkinson’s disease (PD) and many other neuropsychiatric diseases. They also speed up the clinicians and facilitate decision-making for several conditions with similar clinical symptoms. The current study attempts to detect PD with dementia (PDD) by event-related oscillations (EROs) during cognitive processing in two modalities, i.e. auditory and visual. Approach. The study was conducted to discriminate PDD from healthy controls (HC) using event-related phase-locking factors in slow frequency ranges (delta and theta) during visual and auditory cognitive tasks. Seventeen PDD and nineteen HC were included in the study, and linear discriminant analysis was used as a classifier. During classification analysis, multiple settings were implemented by using different sets of channels (overall, fronto-central and temporo-parieto-occipital (TPO) region), frequency bands (delta-theta combined, delta, theta, and low theta), and time of interests (0.1-0.7 s, 0.1-0.5 s and 0.1-0.3 s for delta, delta-theta combined; 0.1-0.4 s for theta and low theta) for spatial-spectral-temporal searchlight procedure. Main results. The classification performance results of the current study revealed that if visual stimuli are applied to PDD, the delta and theta phase-locking factor over fronto-central region have a remarkable contribution to detecting the disease, whereas if auditory stimuli are applied, the phase-locking factor in low theta over TPO and in a wider range of frequency (1-7 Hz) over the fronto-central region classify HC and PDD with better performances. Significance. These findings show that the delta and theta phase-locking factor of EROs during visual and auditory stimuli has valuable contributions to detecting PDD
Synthesis, Crystal Structure, Hirshfeld Surface Analysis, DNA/BSA Interaction and Molecular Docking Studies of 2-(6-(4-chlorophenyl)-1,2,4-triazin-3-yl)quinoline
No full textWe reported herein a new 1,2,4-triazine derivative, 2-(6-(4-chlorophenyl)-1,2,4-triazin-3-yl)quinoline, synthesized by cyclization of p‑chloro isonitrosophenylhydrazine with 2-quinolinecarboxaldehyde. Its structure was elucidated by FTIR, 1H NMR, 13C APT NMR, elemental analyses, and also its molecular and crystal structures were determined by single crystal X-ray analysis which revealed that the compound was crystallized in monoclinic system P 2/c space group with a = 17.2564 (6) Å, b = 6.0419 (3) Å, c = 14.4093 (5) Å, β = 103.469 (3)°, Z = 4 and V = 1461.01 (10) Å3. The Hirshfeld surface analysis of the crystal structure indicated that the most important contributions for the crystal packing were from H … H (29.2%), H … C/C … H (22.3%), H … N/CN … H (16.1%) and H … CI/CI … H (14.5%) interactions. Hydrogen bonding and van der Waals interactions were the dominant interactions in the crystal packing. The evaluation of the electrostatic, dispersion and total energy frameworks indicated that the stabilization was dominated via the dispersion energy contribution. The synthesized compound was investigated for CT-DNA and BSA binding activity using various in vitro and in silico techniques. Results were revealed that binding of the compound with CT-DNA via minor groove and with BSA via subdomain IIIB
Influence of pumice powder on some properties of phenol-formaldehyde bonded particleboards
No full textIn this study, pumice powder as a volcanic aggregate was added in the particleboards' production. The effect of various ratios of pumice powder (10%, 20%, 30%, and 40%) on physical, mechanical, thermal and fire resistance properties was investigated. Pumice powder did not significantly affect particleboards' water absorption and thickness swelling values. However, the mechanical properties were significantly affected with raising pumice powder content. The modulus of rupture and modulus of elasticity decreased up to 46% and 45%, respectively. There was also a decrease in the internal bond strength up to 42%. Conversely, pumice powder improved the thermal degradation temperatures. The onset temperatures increased with increasing pumice powder content above 300°C. Similarly, the pumice powder improved the fire resistance of particleboards up to 7% compared to control samples
