Pre-exponential Factor Research Articles

Risk factors and evolution of weight loss in Parkinson's disease: A 9-year population-based study

IntroductionWeight loss is considered a common complication of Parkinson's disease (PD), but there are few prospective longitudinal studies on weight loss in patients followed from time of PD diagnosis. We sought to determine the frequency, evolution and risk factors of weight loss in a representative incident PD cohort. MethodsIn this prospective population-based observational study, we followed 180 newly-diagnosed, initially drug-naïve PD patients and 161 controls with repetitive weight examinations over 9 years. We used Cox regression models with adjustment for potential confounders to identify independent risk factors of clinically significant (>10 %) weight loss. ResultsMean % weight change during follow-up was −3.9 (±11.2) in patients and −1.4 (±8.1) in controls (p = 0.016). Clinically significant weight loss was observed in 26.7 % of patients and 10.6 % of controls (RR 2.53; 95 % CI 1.52–4.21; p < 0.001). Age was the only independent baseline risk factor for weight loss (HR 1.06 per year; 95 % CI 1.03–1.10; p < 0.001). Additional time-dependent risk factors were presence of olfactory impairment (HR 2.42; 95 % CI 1.14–5.15; p = 0.021), presence of dyskinesias (HR 3.14; 95 % CI 1.58–6.23; p = 0.001), and cognitive impairment (HR per MMSE unit 0.90; 95 % CI 0.82–0.99; p = 0.036). Dopamine agonist use reduced the risk of weight loss during follow-up (HR 0.44; 95 % CI 0.24–0.82; p = 0.007). ConclusionThe risk of weight loss is more than doubled in the general PD population and associated with both disease-related features and drug-related complications. This suggests a multifactorial nature of weight loss in PD, which is important to consider in research and clinical practice.

Performance Evaluation and Wing Deformation Analysis of Flapping-Wing Aerial Vehicles with Varying Flapping Parameters and Patterns

There has been significant interest in the field of bio-inspired robotics, particularly in the development of flapping-wing robots from micro to bird size. Most flapping robots use lever-crank mechanisms or servomotors as wing flapping mechanisms. Servomotor-based flapping has the advantage of being able to generate various flapping patterns according to amplitude, offset, frequency, waveform, and other factors. However, it is not clear how these factors affect thrust generation. Therefore, this study focuses on the force generation and power consumption in different flapping patterns as well as the wing deformation during the flapping motion to provide some insights into the performance improvement. The results showed that the response characteristics of the actuators caused the thrust to saturate at high frequencies, and that sinusoidal pattern could generally achieve good performance and efficiency.

Catalytic behavior, electronic structure and spectroscopic (FT-IR, Raman, UV–vis) properties for the new ionic liquid imidazolium hydrogen sulfate

Catalytic performance, chemical reactivity, vibrational modes and electronic transitions of the ion pair [H–Im]+[HSO4]– were investigated in the current paper. Hence, a combined experimental (Hammett acidity function, infrared, Raman and ultraviolet-visible spectroscopies) and theoretical (molecular electrostatic potential surface, reduced density gradient, frontier molecular orbital analysis, quantum theory of atoms in molecules, net atomic charges, global and local reactivity descriptors) study was conducted. In terms of the catalytic performance, the acetic acid esterification with butanol was evaluated. Important kinetic (rate constant, activation energy, pre-exponential factor) and thermodynamic (enthalpy, entropy, Gibbs free energy barrier) factors for ester production as a function of the temperature and catalyst loading have been determined. Results revealed intensive electron density distribution in [H–Im]+[HSO4]– due to chemical interactions between the cationic and anionic moieties. These bonds were established as electrostatic in nature. The pronounced charge transfers within [H–Im]+[HSO4]– managed the title compound acidity (H0) and its catalytic behavior towards butyl acetate synthesis. Using the thermodynamic and kinetic measurements, a mechanism for acetic acid esterification with butanol in the presence of imidazolium hydrogen sulfate ionic liquid was offered.

In-depth exploration of waste printed circuit boards pyrolysis: Real-time products characteristics, kinetics parameter optimization and reaction mechanism

Pyrolysis is a promising technology for recycling waste printed circuit boards (WPCBs). This study delves into a real-time examination of the volatiles emitted from WPCBs during pyrolysis using thermogravimetric analysis coupled with Fourier transform infrared spectroscopy/mass spectrometry (TG-FTIR/MS), offering an in-depth analysis of the entire pyrolysis mechanism. An optimized kinetic model for printed circuit board (PCB) pyrolysis is developed by the shuffled complex evolution (SCE) algorithm. Results indicate that the main pyrolysis products are phenol and alkyl-substituted phenols, along with hydrogen bromide (HBr) and bromophenols. Bromides exhibit an earlier onset and peak temperature compared to phenolic products. The pyrolysis process can be divided into two stages: initial depolymerization of the resin body into macromonomers, followed by prevalent alkyl removal, homolytic reactions, and isomerization. The apparent activation energy (E) is 155.32 kJ/mol, the pre-exponential factor (ln(A)) is 29.77 min−1, and the kinetic mechanism function is described by (1‐α)2.02. This study provides crucial knowledge to advance the technology of WPCBs pyrolysis.

Exploring the Frequency and Risk Factors of Hyperprogressive Disease in Patients with Advanced Melanoma Treated with Immune Checkpoint Inhibitors.

Hyperprogressive disease (HPD) is described as the unexpected rapid growth of a tumour accompanied by a decline in performance status. While immune checkpoint inhibitors (ICIs) have improved outcomes in advanced melanoma, HPD remains a significant challenge in a subset of patients. Although HPD has been extensively studied in various solid tumours, research specifically focusing on advanced melanoma remains limited. We analysed 158 advanced melanoma patients, with 66.5% (n = 105) receiving anti-PD-1 and 33.5% (n = 53) receiving nivolumab plus ipilimumab. The median overall survival was 4.9 months for patients with HPD compared to 8.9 months for those with progressive disease without HPD (p = 0.014). Factors associated with HPD included liver metastasis (p = 0.002), three or more metastatic sites (p < 0.001), elevated lactate dehydrogenase levels (p = 0.004), and Eastern cooperative oncology group performance status ≥2 (p = 0.023). Multivariate analysis identified the Royal Marsden Hospital score (HR 3.675, 95% CI: 1.166-11.580, p = 0.026) as an independent risk factor for HPD, with the MDA-ICI score also trending towards significance (HR 4.466, 95% CI: 0.947-21.061, p = 0.059). This study provides valuable insights into the frequency and factors associated with HPD in advanced melanoma patients treated with ICIs, highlighting the relevance of clinical markers and scoring systems in predicting HPD risk.

Analysis of early and treatment related deaths among children and adolescents with acute myeloid leukemia in Poland: 2005-2023.

A personalised approach to the treatment of acute myeloid leukemia (AML) in children and adolescents, as well as the development of supportive therapies, has significantly improved survival. Despite this, some patients still die before starting treatment or in an early phase of therapy before achieving remission. The study analysed the frequency, clinical features and risk factors for early deaths (ED) and treatment related deaths (TRD) of children and adolescents with AML. From January 2005 to November 2023, 646 children with AML treated in the centers of the Polish Pediatric Leukemia and Lymphoma Study Group according to three subsequent therapeutic protocols were evaluated: AML-BFM 2004 Interim (385 children), AML-BFM 2012 Registry (131 children) and AML-BFM 2019 (130 children). Out of 646 children, early death occurred in 30 children, including 15 girls. The median age was 10.7 years (1 day to 18 years). More than half of the patients (53%) were diagnosed with acute myelomonocytic leukemia (M5) and 13% with acute promyelocytic leukemia (M3). The ED rate for the three consecutive AML-BFM protocols was 4.9% vs. 5.3% vs. 3.1%, respectively. In 19 patients, death occurred before the 15th day of treatment, in 11 between the 15th and 42nd day. The most common cause of death before the 15th day (ED15) was leukostasis and bleeding, whereas between the 15th and 42nd day (ED15-42), infections, mainly bacterial sepsis. A significant association was found between ED15 and high leukocyte count (>10 × 109/L), M3 leukemia (p < 0.001), and ED15-42 and age <1 year (p = 0.029). In the univariate analysis only initial high leukocyte count >100 × 109/L, was a significant predictor of early death. The overall TRD for the entire study period was 3.4%. The main cause of death were infections, mainly bacterial sepsis (10 children out of 22, 45.4%). Hyperleukocytosis remains significant factor of early mortality in patients with AML, despite the introduction of various cytoreductive methods. Infections are still the main cause of treatment related deaths. A more individualized approach by using new targeted drugs may be the therapeutic option of choice in the future.

Mesoporous, high surface area and microrod-shaped cobalt (II) coordination polymer for assessment of molecular structure, thermolysis and non-isothermal kinetics parameters

This study is significant as it presents the assessment of molecular identification, thermal degradation, and non-isothermal kinetics of a cobalt (II) coordination polymer [Co (II) CPs] synthesized from suberoyl bis (2-ethoxybenzamide) (sbebz) and cobalt acetate through the condensation process. The condensation product sbebz was obtained from suberoyl chloride and 2-ethoxybenzamide. The XRD, FT-IR, Raman, and XPS investigated as aspects to identify its structure, purity, and chemical state. The morphological facet was confirmed by SEM and TEM. The morphology data revealed a microrod-shaped morphology of Co (II) CPs with an average particle size 0.7 µm to 1 µm. The pore size, and surface properties were examined by Brunauer-Emmett-Teller (BET) and atomic force microscopy (AFM), revealing a highly large surface area (1076 m2/g), mesoporous and monodisperse nature. The molecular interaction of ligand was estimated using protein molecule. The thermal-decomposition behavior and non-isothermal kinetics of Co (II) CPs were estimated at different heating rates (5 °C/min, 10 °C/min, 15 °C/min, and 20 °C/min) under nitrogen atmosphere by thermogravimetry/Derivative thermogravimetry (TG/DTG). As-synthesized Co (II) CPs show enhanced thermal stability compared to the ligand (sbebz). The multiple heating TG/DTG curve exhibits a more or less identical degradation profile/pattern. The kinetic parameters like order of reaction (n), pre-exponential Arrhenius factor (A), activation entropy (∆s), activation energy (Ea), activation free-energy (∆G), and activation enthalpy (∆H) were calculated using Coats-Redfern (CR) method.

Advanced resistance exercise combined with aerobic rehabilitation training on cardiopulmonary function

Chronic diseases are the number one killer in the world today, and the most common cause of chronic diseases is lack of exercise. Research on the application of artificial intelligence technology in the medical field can shorten the distance between clinical best practice and practical application, and promote the standardized management of clinicians according to specifications. In this paper, three different exercise methods, continuous aerobic, anaerobic, and control, were used to conduct a 12-week study. This paper discussed the effects of three different forms of exercise on the body shape, body composition, and metabolism of patients with chronic diseases, and discussed the intervention effects of the same exercise mode in different periods (0–6 weeks, 6–12 weeks), to provide a theoretical basis for more effective and targeted choice of exercise intervention programs. Through training load, training frequency, training sequence, training interval, and other factors, a training plan can be designed. To avoid mistakes, experts often try to do some items that are prone to mistakes, especially lung function measurement. The scores of self-care, extraction, standing, occupation/housework, social activities, and total scores were significantly lower than those before intervention (P &lt; 0.01). Advanced resistance kinetic energy can significantly improve the exercise and cardiopulmonary function of patients with various types of chronic diseases. Advanced resistance kinetic energy can significantly promote the strength and explosive force of the shoulder, waist, and back muscles in chronic patients, and can significantly promote the muscle adaptability of the shoulder, waist, and back muscles in chronic patients.

Electrokinetics of Nitrite to Ammonia Conversion in the Neutral Medium Over A Platinum Surface.

Polycrystalline Pt electrode was employed to selectively convert nitrite ions ( ) into useful nitrogenous compound through electrochemical reduction reaction in neutral medium. According to adsorptive stripping analysis, the reduction process produced nitric oxide (NO) on the surface of Pt electrode. The spectroscopic test and gas chromatographic studies discovered the presence of ammonia (NH3) in the electrolyzed solution, suggesting the transformation of adsorbed NO into NH3 during the reverse scan. Scan rate dependent investigation was performed to elucidate kinetic information relating to this reaction on Pt surface. From Ep vs scan rate (υ) and jp vs υ (logarithmic plot), it was found that the conversion of ion into NO is an irreversible reaction which relies on the diffusion of ions to electrode surface. The Tafel analysis unveiled that the first electron transfer sets the overall reaction rate, having formal reduction potential, E0'=-0.46 V and standard heterogeneous rate constant, k0= cm s-1. Reductive transfer coefficient (α) is another kinetics parameter, which was found to be approximate 0.77 from the difference between Ep and Ep/2 of the voltammograms obtained over scan rate range 0.005 V s-1 to 0.250 V s-1, indicating a stepwise process. According to temperature-dependent voltammograms, the nitrite reduction reaction on Pt had a calculated activation energy of about 19.8 kJ mol-1 and a pre-exponential factor of about 8.39×103 mA cm-2.

Frequency and risk factors of postoperative hyponatremia in primary hip and knee arthroplasties patients at a tertiary care hospital, Karachi, Pakistan

Frequency and risk factors of postoperative hyponatremia in primary hip and knee arthroplasties patients at a tertiary care hospital, Karachi, Pakistan

Determining domestic violence against women using machine learning methods: The case of Türkiye.

Domestic violence against women is a pervasive issue globally, representing a severe violation of human rights and a significant public health concern. The hidden nature of such violence and its frequent underreporting make it a critical area for research. Recent advancements in artificial intelligence offer new avenues for identifying and predicting instances of domestic violence through machine learning (ML) algorithms. This study aimed to determine the frequency and risk factors of domestic violence against women using ML methods. With a cross-sectional design, this research was conducted with 630 married women between December 2023 and February 2024. Data were obtained using the 'Demographic Information Form' and the 'HITS Domestic Violence Scale'. Data analysis used six ML algorithms (decision tree, random forest, support vector machine [SVM], logistic regression [LR], Naive Bayes and k-nearest neighbour). In our study, the rate of women experiencing violence was determined to be 11%, while the duration of marriage, number of children and level of education were identified as significant risk factors. Threat, insult and injury were common risk factors in all algorithms. SVM and LR algorithms were effective models in predicting violence with a 100% accuracy rate. All ML algorithms' sensitivity ranged from 91.12% to 100%, while specificity ranged from 85% to 100%. The findings of our study demonstrate that ML algorithms have high accuracy rates in determining the frequency and risk factors of domestic violence against women, indicating that they can be used safely.

Antibacterial Effects of Thermosonication Technology on Salmonella typhimurium Strains Identified from Swine Food Chain: An In Vitro Study.

Among innovative food technologies, ultrasounds have demonstrated physical damages (provided by frequency and intensity factors) on bacterial structures while determining the microbiological stabilization of many foodstuffs. This study tested the efficacy of the thermosonication process on 16 Salmonella typhimurium strains belonging to the academic biobank (isolated from swine slaughterhouses). All strains were exposed to focused ultrasounds, generated by the Waveco® system (Milan, Italy), with the following settings: 40 KHz coupled with 80 W at different 5 min intervals starting from 5 to 15 ones, and focusing on two different temperatures: 40 °C and 50 °C. After each treatment, all strains were directly plated onto count agars immediately (t0) and after 24 h (t24) of storage at refrigerated temperature. The results showed bacterial reductions by prolonging the sonication treatments until 15 min (i.e., 50 °C for 15 min reduced of 2.16 log CFU/gr the initial loads). In the present in vitro study, the most considerable decrease was observed after 24 h. It meant that Salmonella strains were lethally damaged at the wall level, confirming the ultrasound bactericidal effect on loads. The present in vitro scientific investigation demonstrates the practical bactericidal effects of thermosonication, highlighting promising applications at the industry level for food microbial stabilization and shelf-life prolongation.

Early arrhythmia after cardiac surgery in children with congenital heart disease

Objective. To analyze the frequency and risk factors for arrhythmia in children with congenital heart disease in the early period after cardiac surgery. Materials and methods. A retrospective analysis of the incidence and risk factors for arrhythmia in 285 children who underwent cardiac surgery in the Department of Surgical Treatment of Congenital Heart Diseases in Newborns and Young Children at the Amosov National Institute of Cardiovascular Surgery of the National Academy of Medical Sciences of Ukraine for the period from 2021 to 2023 was performed. There were 202 children under the age of 18. Results. In the early postoperative period, heart rhythm disturbances occurred in 53 (26.2%) of 202 patients: 28 had supraventricular tachycardia, 16 had bradyarrhythmia (atrioventricular block), 6 had ventricular tachycardia, and 3 had nodal ectopic tachycardia. It was found that plastic surgery of the interventricular and atrial septal defect in isolation or in combination with interventions for other defects (Fallot's tetrad, transposition of the great vessels, atrioventricular communication) and bidirectional and total cavopulmonary anastomoses are associated with a high risk of arrhythmia. Statistically significant (p &lt; 0.05) risk factors for arrhythmia were: lactate level of more than 2 mmol/L, duration of cardiopulmonary bypass more than 185 minutes, duration of aortic clamping more than 67 minutes. Conclusions. Arrhythmia often complicates the course of the early period after cardiac surgery in children and requires timely and correct action. Prolonged cardiopulmonary bypass, aortic constriction, and lactatidosis are risk factors for arrhythmia. Plastic surgery of the interventricular and atrial septal defects, as well as palliative reconstructive heart surgery, are associated with frequent cardiac arrhythmias in the early postoperative period.

Study on the Thermal Effect of Spontaneous Combustion of Coal-Based Activated Carbon By-Products Oxidized and Carbonized Powders

ABSTRACT To investigate the spontaneous combustion thermal effect of the by-products oxidized powder (OP) and carbonized powder (CP) produced during the preparation of coal-based activated carbon (CBAC). First, the changes in composition and pore structure of OP and CP compared with raw coal (RC) were measured by coal quality analysis and nitrogen adsorption experiments. The ability of OP and CP to physically adsorb oxygen was determined. Then, differential scanning calorimetry (DSC) was used to study the whole process thermal effect of the spontaneous combustion of OP and CP. Finally, the thermal effect of OP and CP during low-temperature oxidation process was further explored by the C80 micro-calorimeter, and the thermodynamic characteristics were also probed. The results show that the content of fixed carbon and carbon elements in OP and CP are significantly greater than that in RC, which makes the pore structure of both complicated. In addition, the total pore volume, average pore size, and specific surface area of OP and CP are greater than that of RC, which is more conducive to the physical adsorption of oxygen by both. No transition platform is caused by the decomposition of intermediate products on the DSC curve of CP. The characteristic temperatures of CP (except T D10) are lower than that of OP, indicating that the spontaneous combustion reaction of CP started earlier than that of OP. However, part of the combustible substance of CP was consumed in the dry distillation process, leading to the thermal release and maximum thermal release rate being smaller than that of OP. The apparent activation energy (E a) of stages H2 and H3 in the low-temperature oxidation process of OP is 75.04 and 11.42 kJ mol−1, while that of CP is 83.11 and 30.91 kJ mol−1. The threshold of CP entering stages H2 and H3 is higher than that of OP. Nevertheless, from the pre-exponential factor (A), the low-temperature oxidation process of CP is more rapid.

Feline blood donation: Description and adverse reactions from 29 201 donation events between 2019 and 2023.

Feline blood transfusion is required for the treatment of various illnesses in cats, and the safety of donor cats is vital. Donor adverse reactions can include cardiorespiratory, venepuncture-related, and behavioral abnormalities. To describe a large number of feline blood donation events and document use of sedation and anxiolysis, record volume of blood collected and describe the frequency, type, and risk factors for, adverse reactions. The study included 7812 individual cats and 29 201 donation events at a blood banking center over 5 years. Retrospective analysis of donation event records with signalment, donation volume, sedation status, donation number, and adverse reactions (acute and caregiver reported) recorded. Risk factors for adverse reactions were examined by stratifying data according to groups exposed to relevant predictors and calculating odds ratios with 95% and 99% confidence intervals (CIs). Adverse reactions were uncommon (0.29%, 2.88/1000 donor events) and most commonly were cardiorespiratory (0.08%, 0.75/1000 donor events) or behavioral (0.06%, 0.62/1000 donor events). The only risk factor significantly associated with adverse reactions was conscious donation, with conscious donors 4.4 times more likely to have an adverse reaction (95% CI, 2.5-7.9, P ≤ .0001). Feline blood donation is associated with a low rate of adverse reactions. Sedation should be considered to reduce adverse reactions, and the environment and interactions optimized to reduce donor stress. Caregiver education on care postdonation could reduce behavioral adverse reactions.

Theoretical Investigation into Polymorphic Transformation between β-HMX and δ-HMX by Finite Temperature String

Polymorphic transformation is important in chemical industries, in particular, in those involving explosive molecular crystals. However, due to simulating challenges in the rare event method and collective variables, understanding the transformation mechanism of molecular crystals with a complex structure at the molecular level is poor. In this work, with the constructed order parameters (OPs) and K-means clustering algorithm, the potential of mean force (PMF) along the minimum free-energy path connecting β-HMX and δ-HMX was calculated by the finite temperature string method in the collective variables (SMCV), the free-energy profile and nucleation kinetics were obtained by Markovian milestoning with Voronoi tessellations, and the temperature effect on nucleation was also clarified. The barriers of transformation were affected by the finite-size effects. The configuration with the lower potential barrier in the PMF corresponded to the critical nucleus. The time and free-energy barrier of the polymorphic transformation were reduced as the temperature increased, which was explained by the pre-exponential factor and nucleation rate. Thus, the polymorphic transformation of HMX could be controlled by the temperatures, as is consistent with previous experimental results. Finally, the HMX polymorph dependency of the impact sensitivity was discussed. This work provides an effective way to reveal the polymorphic transformation of the molecular crystal with a cyclic molecular structure, and further to prepare the desired explosive by controlling the transformation temperature.

Dy3+ doped Zn0.66Mg0.3Al2O4 nanophosphor for high dose radiation thermoluminescence dosimetric applications

Zinc Magnesium Aluminate doped with Dysprosium (Zn (1-x-y) Mg(y)Al2O4:x Dy (x=0.04 and y=0.3 mol%)) was prepared using the solution combustion synthesis method. The prepared phosphor was characterized using energy-dispersive X-ray spectroscopy, scanning electron microscopy, X-ray diffraction, transmission electron microscopy, and Fourier transform infrared, respectively, to study crystal structure, surface morphology, and vibrational properties. The thermoluminescence peak temperatures were 250°C, 248°C, and 246°C at irradiating doses of 600–1000 Gy, respectively. Through the computation of the activation energy (E), order of kinetics (b), and frequency factor (s−1), the kinetic parameters were assessed using the TL glow curve. It is observed from the TL dose-response curve that the intensity rises nearly linearly for all doses between 600 and 1000 Gy. Nanophosphor Zn0.66Mg0.3Al2O4:0.04Dy shows almost linear dose-response for a dose range of 600–1000 Gy and an optimum activation energy (E) of 0.93–0.97 eV, which makes it suitable for high-dose radiation thermoluminescence dosimetric applications.

Evaluation of akathisia in patients receiving selective serotonin reuptake inhibitors/serotonin and noradrenaline reuptake inhibitors.

Akathisia is an underestimated but disturbing extrapyramidal side effect of antidepressants, which could reduce treatment compliance in mood disorders. This study aimed to investigate the frequency and risk factors in patients treated with selective serotonin reuptake inhibitors/serotonin and noradrenaline reuptake inhibitors (SSRI/SNRI). In addition, we assessed the impact of akathisia on the quality of life (QoL). Patients were aged between 18 and 75 years, receiving an SSRI/SNRI for 4-8 weeks, and were diagnosed with anxiety, depression, or obsessive-compulsive disorder. The Barnes Akathisia Rating Scale was used to assess the severity of the akathisia. QoL was evaluated using the Short Form 36 (SF-36) questionnaire. Akathisia was observed in 25% (50/198) of patients. Smokers and younger patients were more frequent among patients with akathisia. Physical functioning, physical role, vitality, and mental health domains of the SF-36 were reduced in the presence of akathisia. In conclusion, our results suggest that akathisia is not a rare side effect of SSRI/SNRI in patients with mood disorders, especially in smokers and younger patients. In addition, akathisia may reduce treatment compliance owing to a reduction in QoL. Further investigations are needed to confirm the risk factors, frequency, and consequences of treatment compliance for SSRI/SNRI-induced akathisia in patients with mood disorders.

Kinetics study of pyrolysis of petroleum sludge and characterization of char

Thermochemical conversion (or pyrolysis) has emerged as an effective technique for the disposal of sludge generated in process industries. This paper reports physicochemical characterization and kinetic analysis of pyrolysis of sludge from a petroleum refinery and characterization of resultant char. The sludge had high volatile matter (>70 wt%) and low ash content (15 wt%). Pyrolysis of sludge was studied using a thermo-gravimetric analyzer (TGA). The TGA data was analyzed using two isoconversional models, viz. KAS and Vyazovkin AIC are used for the deduction of kinetic triplets, viz. activation energy, pre-exponential factor, and reaction mechanism. The activation energy (Ea ) of sludge pyrolysis varied in the 64.79–190.37 kJ/mol range. The pre-exponential factor varied from 1.18E + 07 to 4.29E + 12 s−1. The predominant solid-state mechanism of thermal conversion was an order-based reaction (F2/F3). The thermodynamic factors (viz. ΔH, ΔS, ΔG) of sludge pyrolysis were also determined. Relatively small values of (Ea – ΔH) ∼ 5 kJ/mol revealed high susceptibility of sludge for thermal conversion. Residual char after pyrolysis was characterized for physicochemical properties. The char properties were fixed carbon = 54.37%, calorific value = 22.48 MJ/kg, and BET surface area = 18.35 m2/g. These properties make char suitable for numerous applications.

Assessment of the frequency and risk factors of gastrointestinal bleeding after cardiopulmonary bypass in paediatric cases.

Gastrointestinal bleeding is a potential complication in paediatric patients undergoing cardiopulmonary bypass, as it develops secondary to low gastrointestinal perfusion. This study aimed to examine the incidence of gastrointestinal bleeding and identify its risk factors in these patients. This retrospective study was undertaken to examine the demographic features, clinical findings, and operative data of paediatric patients under years old who had undergone congenital heart surgery with cardiopulmonary bypass between November 1, 2021, and November 1, 2023. The study aimed to investigate the incidence of gastrointestinal bleeding associated with cardiopulmonary bypass and to identify potential risk factors for gastrointestinal bleeding. The obtained results were statistically evaluated. The study period included 1100 patients who underwent congenital heart surgery with cardiopulmonary bypass. Fifty-two percent of the total participants were male. The median weight of the patients was 4.4 kg, with an interquartile range of 3.5-5.8 kg. The patients were categorised by age, revealing that 62% were newborns, 24% were infants, and 14% were children. Forty-four (4.2%) of the total number of patients experienced gastrointestinal bleeding. Newborns had a significantly higher incidence of bleeding (6% or 34 patients) compared to infants (3% or 8 patients) and children (1.5% or 2 patients) (p < 0.05). Patients who experienced gastrointestinal bleeding had a longer median hospital stay of 24 days compared to those who did not, with a median hospital stay of 14 days. Moreover, patients who suffered from bleeding had a significantly higher mortality rate (30%) in comparison to those who did not (9.9%) (p < 0.05). The incidence of gastrointestinal bleeding was found to be associated with several risk factors, such as low operative age and weight, high surgical score, presence of low cardiac output syndrome, extracorporeal membrane oxygenation (ECMO) usage, high lactate levels, and low platelet count. Gastrointestinal bleeding is a potential complication for patients who undergo cardiopulmonary bypass. It is particularly relevant for newborns who have undergone prolonged surgery, have a high surgical complexity score, exhibit high lactate levels, display low cardiac output, utilise ECMO, and possess low platelet counts. In such cases, there may be a heightened incidence of gastrointestinal bleeding. It is important to consider this possibility in order to ensure the best possible patient outcomes.