1st Stage Research Articles

Chemical insight into thermal degradation, chemical kinetics, and thermodynamics behavior of sewage sludge through thermogravimetry and Fourier transform infrared analysis

Pyrolysis emerges as a promising path for sewage sludge (SS) management and value creation by producing compounds with enhanced utility. This study focuses on a comprehensive analysis of the thermal decomposition of SS using thermogravimetric analysis (TGA) and Fourier transform infrared spectrometry (FTIR). The TGA and FTIR were employed to evaluate the pyrolysis behavior, kinetics, and characteristics during pyrolysis of SS. The process revealed three distinct stages: 1st stage ranged between 30–185 °C with the removal of moisture, 2nd stage saw devolatilization of SS in the range of 185–595 °C, and the 3rd stage was mainly the formation of char in the temperature range of 595–900 °C. Pyrolysis kinetics, reaction mechanisms, and thermodynamic properties were extensively investigated at three different heating rates of 10, 20, and 30 °C /min. It was observed that with the temperature rise, the decomposition rate also increased rapidly, notably for the heating rate of 30 °C/min. Using Flynn-Wall-Ozawa, Kissinger-Akahira-Sunose, Starink, and Tang methods, activation energies for SS pyrolysis were estimated for α in the range of 0.2–0.85, and the average value for that range was found to be 84.72, 92.29, 91.99, and 91.76 kJ/mol, respectively for different iso-conversional methods. The chemical kinetics analysis through Coats-Redfern methods identified that 3-D diffusion-reaction mechanisms have the highest coefficient of determination among the other models. Criado z-master plot emphasizes the prevalence of Avrami-Erofeev (A4) as the bestsuited reaction model in combination with α, providing a detailed examination that illuminates the complex processes and mechanisms inherent in the pyrolysis of sewage sludge.

THE USE OF CELL SAVER IN PROSTHETIC JOINT INFECTION SURGERY: IS IT REALLY CONTRAINDICATED?

The benefits of cell salvage autotransfusion are well reported. There is a common non-evidenced belief amongst revision arthroplasty surgeons that auto-transfusion is potentially contraindicated in infected revisions.The aim is to study the immediate and delayed outcomes of using cell saver on patients undergoing PJI surgery.Prospective cohort service evaluation registered with the local audit department. 20 PJI cases in 18 patients where cell saver was used over a period of 4 years. Intraoperative fluid and tissue samples were taken for culture. Blood culture from salvaged blood pre and post leucodepletion filter were sent for microbiological analysis. Data on type of surgery, blood loss, further allogenic transfusion and SIRS response was collected. Success of infection clearance was assessed using 2019 MSIS ORT. Five patients receiving autologous blood in non-infection cases were used as controls.Mean age for the PJI group was 67.7 years, 67% female. 11 patients (67%) had 1st stage surgery and 5 (25%) underwent 2nd stage whereas 4 patients had single stage surgery. The mean calculated blood loss was 1398 mls (range 400–3000mls). 6 Patients required further allogenic transfusion. 16 patients received blood via a leuco-depletion filter. The same organism grown from tissues was identified in post-filter blood in 8/17 patients (47%).2/20 have grown a different organism in post-filtered blood, _P.Acne._2 patients developed SIRS upon auto-transfusion, however one was thought to be secondary to cementing. The control group had 443 mls mean amount of blood loss and 1 patient developed a SIRS response.14/20 (70%) patients had successful clearance of infection (tier 1) 2 patients died prior to undergoing 2nd stage.Using cell saver did not impact main outcome of infection clearance in PJI surgery. We would advocate its routine usage whilst avoiding direct collection of heavily contaminated blood.

Improving the photovoltaic performance of CIGS solar cells with the modified 3-stage co-evaporation process

The 3-stage co-evaporation process has been adopted as one of the standard deposition techniques for developing high efficiency CuIn1-xGaxSe2 (CIGS) thin film solar cells. This method often results in a double-graded [Ga]/([Ga] + [In]) or x value, leading to a double-graded bandgap in the CIGS films. The main challenge is to increase open-circuit voltage (Voc) without losing short-circuit current density (Jsc) of the devices. To achieve this goal without extra elemental sources or processes during fabrication, the standard 3-stage co-evaporation process could be modified by adjusting the deposition rate of Ga in the 1st and 3rd stages to enhance the double-graded profile of x. In the 1st stage, x1 is varied in the range of 0.37–0.60, whereas x3 is varied in the range of 0.15–0.37 in the 3rd stage. This is to be compared with our reference 3-stage process using constant x1 = x3 = 0.37. The effects of the x values on the photovoltaic properties of the CIGS devices and the elemental depth profiles of the CIGS absorber have been examined. In this work, the champion device has a maximum efficiency of 17.61 %, a Voc of 698.4 mV, a Jsc of 33.81 mA/cm2 and a fill factor (FF) of 76.12 %. This was achieved by using x1 = 0.55 and x3 = 0.25. These parameters demonstrate a significant beneficial improvement over reference 3-stage process and result in the notch position (the minimum of the x value) being approximately 500–800 nm below the surface of the CIGS films.

Selectivity of the Premixtures Flufenacet, Diflufenican and Flufenacet, Diflufenican, Metribuzin on Bread Wheat (Triticum aestivum L.) and Barley (Hordeum vulgare L.) and Efficacy on ALS/ACCase-Resistant Populations of Lolium rigidum Gaudin

The premixtures flufenacet plus diflufenican and flufenacet plus diflufenican plus metribuzin are two herbicides recently registered in Greece for weed control in bread wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) with application early post-emergence to the crop (1st–3rd leaf growth stage). To evaluate the selectivity of these new herbicides, pot experiments were conducted by applying flufenacet plus diflufenican at 240 + 120 g ai ha−1 and flufenacet plus diflufenican plus metribuzin at 119.7 + 119.7 + 44.8 g ai ha−1 to bread wheat and barley, at 1st (BBCH-11), 2nd (BBCH-12) and 3rd (BBCH-13) leaf growth stage. The efficacy of the herbicides at the above-mentioned rates in pre-emergence application was also tested on three ALS/ACCase herbicide-resistant populations of Lolium rigidum Gaudin in comparison with the pre-emergence herbicides prosulfocarb and chlorotoluron plus diflufenican at 3200 g ai ha−1 and 1380 + 92 g ai ha−1, respectively. The results revealed decreased selectivity of both premixtures when applied at BBCH-11 for both winter cereals, with flufenacet plus diflufenican being less selective compared to flufenacet plus diflufenican plus metribuzin. Both herbicides highly controlled the three herbicide-resistant L. rigidum populations. The results indicated that both premixtures are effective chemical options for the management of herbicide resistant L. rigidum. To ensure crop safety and optimize efficacy, application at BBCH-12 is recommended.

Intraoperative transcutaneous electroacupoint stimulation on early postoperative fatigue in patients with Parkinson's disease undergoing deep brain stimulation surgery

BackgroundIn this clinical trial, we evaluated the effects of transcutaneous electroacupoint stimulation (TEAS) on postoperative fatigue (POF) in Parkinson disease (PD) patients undergoing deep brain stimulation (DBS) surgery. MethodsA total 60 PD patients undergoing DBS surgery were enrolled. They were randomized to receive either electrical stimulation [alternative frequency 2/10 Hz, dense and disperse, intensity adjusted to the maximum tolerated by the participants (6–15 mAmp)] via surface electrodes (TEAS group) or surface electrodes only without electrical stimulation (Con group) at bilateral Zusanli and Sanyinjiao acupuncture points. All participants received their assigned intervention (TEAS or Con) during the 1st stage of surgery [(except during microelectrode recording (MER)] and the entire 2nd stage of surgery. Intraoperative anesthetic requirements were adjusted based on bispectral index (BIS) monitor. POF was assessed by Christensen fatigue scales (ChrFS), along with Quality of Recovery-15 (QoR-15) and mini-mental state examination (MMSE) postoperatively over a 7-day-period. We recorded the usage of rescue analgesics and anti-emetics. ResultsFifty-nine patients’ datasets were included for final analyses. Fewer patients in TEAS experienced severe POF (defined as ChrFS ≥6) at T3 than those in the Con group (TEAS vs. Con: 7 vs. 22, p < 0.001). During the 1st stage of surgery, more patients in Con group required dexmedetomidine infusion (TEAS vs. Con: 2 vs. 6; P < 0.01). Total dosages of propofol and remifanil during the 2nd stage of surgery were TEAS vs. Con: 374.7 ± 61.2 vs 421.5 ± 81.9; p < 0.001 and 572.3 ± 82.0 vs. 662 ± 148.2; P < 0.001, respectively. Postoperative rescue analgesics (TEAS vs. Con: 2 vs. 6; P < 0.001) were used less in the TEAS group. TEAS patients reported better POF, MMSE and QoR15 scores than those in the Con group during most of the assessment period. ConclusionsIntraoperative TEAS decreased the severity of POF, reduced intraoperative anesthetic requirements and facilitated post-DBS recovery in this group of PD patients.

Health as a value for рuрils and students of higher education is an object for forming an active life position of Combat Horting athletes

The scientific publication analyzed the literature related to: identification of scientific works on the categories of «health» – value for рuрils and students of higher education and «combat horting»; theoretical study of the concept of «values». Three stages of the pedagogical experiment are described (1st stage: summarization of data from literary sources from a specific research direction; 2nd stage: description of theoretical training; 3rd stage: determination of the sequence of value orientations and the place of health as a value in students and students of higher education education: the ratio of levels between respondents regarding values-goals). Table 1 presents the generalized results of the respondents regarding the values-goals: рuрils-athletes of Combat horting (9th grades (n=807) and students of higher education (n=67). And in Table 2 and Figure 1 – the generalized results of the ratio of levels between respondents regarding values-goals: рuрils-athletes of Combat Horting and students of higher education – future coaches (author: Z. Dikhtiarenko). The purpose of the study is to prove the expediency of timely teaching of theoretical material on preserving and strengthening health as a value in рuрils-athletes of Combat Horting and and students of higher education - an object for forming an active life position of Combat Horting athletes. Research methods: analysis of scientific and methodological literature, pedagogical observation, calculation of the arithmetic mean, establishment of the percentage ratio between groups, M. Rokych's method «Value orientations». The experiment was supplemented with two more values-goals: a successful sports career / achieving high sports results; active life position (author: Z. Dikhtyarenko). Therefore, the defined goal of the publication was achieved, and these research results are proof of the feasibility of timely teaching of theoretical material on preserving and strengthening health as a value for pupils and students.

[On the formation of Russian pulmonology: the development of the doctrine of lung diseases (first half of the 20th century)].

The articles on the history of Russian pulmonology presented in the historical, medical and therapeutic literature contain materials for this history, but their authors did not solve the problem of its consistent presentation, highlighting the stages of formation and founders. The authors of this study critically reviewed the literary and archival primary sources, for the first time proposed the identification of three stages in the development of Russian pulmonology and indicated eight of its founders at these stages. The abundance of material did not allow us to present it in one article. This article is devoted to the 1st stage of the history of pulmonology - the formation of the doctrine of lung diseases. The second (development of pulmonology as an independent scientific direction in internal diseases) and the third (organizational design of pulmonology as a new independent clinical scientific and educational discipline and medical specialty, i.e. its institutionalization) stages will be discussed in the next articles.

Design and implementation of a fully differential 2nd‐order CIFF DSM with the synthetic techniques of novel CDS chopper‐integrator and DER using additive‐error capacitors

SummaryCompared to the independent application of chopper stabilization or correlated double sampling (CDS), this paper proposed a 2nd‐order cascade of integrators with feedforward delta–sigma modulator (DSM) utilizing an innovatively synthetic technique of chopper‐integrator within CDS at 1st stage for reducing the flicker noise and DC offset cancelation from about 9.5 mV to −4.4 μV ± 115.6 μV (δ). On the regard of further enhancing the noise suppression and mitigating the nonlinearities of capacitor mismatch, instead of applying the dynamic elements randomization (DER) to the nonlinear correction of DAC under multi‐bits quantizer, here the operation of 3‐bits DER with scrambler has been intelligently employed on the 2nd integrators' sampling capacitors to gain the 2nd noise‐shaping characteristic in spite of 1‐bit quantizer. The noise floor could be theoretically scaled down by −16.1 dB at input frequency of 10 kHz within the limited bandwidth of 100 kHz. The prototype DSM was manufactured in 180‐nm BCD process with an active area of 0.2625 mm2 and achieves the SNDR‐based Schreier figure‐of‐merit (FoMS) of 144 dB and Walden figure‐of‐merit (FoMW) of 25.96 pJ/conv under a 3.3 V supply at 10 kHz working frequency.

Effectiveness of Sacral Massage on Labor Pain and Satisfaction Among Antenatal Mothers in Active Phase of Labor

Background: Massage is a powerful old technique &amp; non pharmacological pain control during 1st stage. Satisfaction of mothers during birth is rather important in terms of women's health and positive family relations. Objective of the study is to assess the effectiveness of Sacral Massage on labour pain and satisfaction among antenatal mothers. Methodology: A quantitative research approach and true experimental research design was adopted; 60 antenatal mothers were selected by simple random sampling. Sacral massage was administered for 3 cycles each for 30 minutes at 5-10cm using superficial massage, deep friction &amp; effleurage during active phase of labor and routine care was given to the control group. After intervention post test was conducted. Results: Study showed before Sacral massage the computed ‘t’ value (-0.36) was found to be statistically non-significant at 0.05 level of significance and after Sacral massage it was (-24.7) was statistically significant at &lt;0.01 level of significance, there were significant difference in mean post test score of labor pain in both groups. Majority (86.6%) mothers were moderately satisfied, followed (13.3%) were highly satisfied with Sacral massage. Conclusion: Sacral massage was found effective to reduced pain and increase satisfaction.

Comparative assessment of hemodynamic parameters during anesthesia in orthopedic and traumatological operations on the lower extremities in children

   Objective. To conduct a comparative analysis of hemodynamic parameters during orthopedic and traumatological operations on the lower extremities in children performed under conditions of multicomponent balanced general and combined anesthesia.   Materials and methods. A single-center prospective study. The present study included 60 children aged 6 to 17 years who underwent planned orthopedic and trauma surgery interventions on the lower extremities. Patients were divided into two groups depending on the method of anesthesia: Group 1 (n = 25) - multicomponent balanced general anesthesia, Group 2 (n = 35) - combined anesthesia (multicomponent balanced general anesthesia in combination with regional blocks of the sciatic and femoral nerves). To solve these problems, a comparative analysis of heart rate, systolic, diastolic and mean arterial blood pressure was carried out at seven stages of the study: 1st stage - initial, child on the operating table; 2nd stage - induction of anesthesia; 3rd stage - placement of the laryngeal mask; 4th stage - start of the operation; 5th stage - traumatic stage of the operation; 6th stage - completion of the operation; 7th stage - after removal of the laryngeal mask.   Results. In all cases, the surgical interventions were successful. The study found that in the group of children who underwent multicomponent general anesthesia at the 4th (start of surgery), 5th (traumatic stage of surgery) and 6th (end of surgery) stages, heart rate (HR) was higher compared to the group of combined anesthesia. Systolic and mean arterial blood pressure during the traumatic phase of surgery were also higher in children undergoing multicomponent general anesthesia. The values of diastolic blood pressure did not differ between groups throughout the study with the exception of the 3rd stage (laryngeal mask placement) where lower values were observed in patients of the Group 1. Diastolic blood pressure values did not differ between groups throughout the study, with the exception of 3th stage (laryngeal mask placement), where lower values were noted in Group 1 patients.   Conclusion. Combined methods of anesthesia based on the combination of multicomponent general anesthesia and conductive peripheral nerve blocks provide the greatest hemodynamic stability during orthopedic and traumatologic surgeries on the lower extremities in children.

A novel high-entropy spinel ferrites (CoNiCuZnMg)Fe2O4 catalyst for H2 production via steam reforming of derived volatiles from polypropylene and waste cooking oil

Municipal organic waste conversion to high-value products is a vital carbon–neutral way to simultaneously tackle the energy crisis and environmental contamination. This study aims to develop and evaluate a novel high-entropy spinel ferrites (Co0.2Ni0.2Cu0.2Zn0.2Mg0.2)Fe2O4 catalyst (HEO) toward H2 production from co-pyrolysis volatiles of polypropylene (PP) and waste cooking oil (WCO) in an integrated two-stage reactor system. In the 1st stage of medium temperature reforming, the optimal 3:7 PP/WCO blend mass ratio facilitated H2 production. Under a catalytic reforming at high temperature of 750 °C in the 2nd stage, the HEO catalyst demonstrated remarkable efficiency, yielding 58.43 mmol·g−1 of H2 with a composition of 65.17 %, a notable 22.3 times higher than that without HEO. The catalyst exhibited a prolonged service life of 540 min without compromising H2 selectivity, maintaining a high yield of 510.2 mmol·gcat.−1·s−1. The exceptional performance of HEO arises from the synergistic effects of multiple elements, augments oxygen vacancy, enhances reducibility, and promotes structural stability in the high-entropy system, which causes the strong C–C breaking ability and the excellent C–H breaking abilities of Fe, Ni, Co, Cu, and Zn species. The analysis of tar, gaseous products, and deactivated HEO catalyst characterization results provides a comprehensive understanding of the co-pyrolysis route and volatiles catalytic reforming process. This study developed a high-entropy ferrite catalyst that not only achieves efficient and stable H2 production but also lays the foundation for a new high-entropy catalyst design concept, fostering the development of efficient reforming catalysts for H2 production.

Long-term results of treatment of a patient with basilar invagination complicated by distal kyphosis and compressive ischemic cervical myelopathy: a clinical case and a brief literature review

Objective. To present a clinical case of surgical correction of a craniovertebral anomaly complicated after 8 years by distal junctional kyphosis, stenosis, antelisthesis of the C5 vertebra and compressive ischemic cervical myelopathy in the C5–C6 segment.Material and Methods. When treating a 56-year-old patient with multiple anomalies of the craniovertebral region, differentiated surgical technologies were consistently used due to the development of late complications. The sequence and rationale for surgical decision making is described.Results. Initially, the patient underwent transoral decompression and posterior occipitocervical fixation, and after 8 years - reinstallation of the system with distal extension of the instrumentation zone to the C7 vertebra with indirect posterior decompression of the spinal cord, anterior discectomy with direct decompression and cage fixation at the C5–C6 level. Regression of myelopathic syndrome, correction of orthopedic status and significant improvement in functional status were achieved.Conclusion. A rare clinical observation demonstrates a combination of basilar invagination with assimilation of the atlas, which has provided rationale for two-stage surgical treatment in one surgical session (1st stage – transoral resection of the dens and 2/3 of the C2 vertebral body with anterior decompression of the spinal cord, and 2nd stage – occipitocervical fixation). The use of extended systems in this case caused the development of a clinically significant syndrome of the distal adjacent level, which required repeated surgical treatment after 8 years.

Abstract 892: Pan-cancer tumor microenvironment profiling with multiplexed immunofluorescence microscopy and self-supervised learning

Abstract Multiplexed immunofluorescence (mIF) microscopy reveals the spatial architecture of cancer tissue and its microenvironment that is not being fully explored with existing analysis methods. Most analysis approaches for mIF microscopy data focus on single-cell or region classification and rely on supervised machine learning. In this work, we present a self-supervised spatial profiling method for mIF images that takes local and global associations into account, and apply this method to profile cancer-associated fibroblasts (CAFs) in a pan-cancer dataset. We studied a 2-stage self-supervised training scheme to learn the representations of mIF tissue microarray (TMA) images in local and global scales (cellular and long-range associations). During the 1st self-supervised training stage, a Vision Transformer learns the local-scale representations by using small patches from TMA images. Then, the local representations are used as input to the 2nd stage where a similar self-supervised learning strategy is used to learn global patterns in the TMA images. We applied the method to profile multiple cohorts from three different solid tumors: prostate, renal, and lung cancer. In total, these cohorts include more than 5,000 TMA cores from over 1,750 patients extracted from the tumor center, tumor edge, and adjacent benign areas. The samples were stained with a CAF panel including FAP, aSMA, PDGFRB, pSTAT3/PDGFRA, nuclear and epithelial markers, and imaged with cyclic mIF microscopy. Samples were studied at the patch-level and TMA core-level. Small patches enable further analysis of associations in the local environment, whereas the core-level enables associations with patient clinical information. Clustering of patch-level (1st stage) and core-level (2nd stage) representations showed independently that self-supervised learning is capable of learning the representations of the mIF images. We were able to identify regions and cases with high pTNM staging from the prostate cancer samples and similar histological subtypes from renal cancer samples. We further validated the clustering using k-NN classification that showed high classification accuracy in all cohorts. Moreover, we developed a stopping criteria for the final model selection that balances between the similarities of samples and patches inside of samples to prevent overfitting. Our study shows that self-supervised learning enables unbiased discoveries from large-scale mIF microscopy imaging datasets. The developed method uncovers associations between imaging data and clinical information and highlights directly the patterns that are most meaningful for these associations. Citation Format: Gantugs Atarsaikhan, Isabel Mogollon, Katja Välimäki, Tuomas Mirtti, Teijo Pellinen, Lassi Paavolainen. Pan-cancer tumor microenvironment profiling with multiplexed immunofluorescence microscopy and self-supervised learning [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 892.

Death Anxiety and Depression among Cancer Patients: Role of Perceived Social Support

The primary objective of this study was to investigate the relationship between death anxiety and depression in individuals coping with cancer, focusing specifically on the role of perceived social support as a protective factor. The sample consisted of 200 cancer patients (95 males, 105 females) from hospitals in Rawalpindi and Islamabad, spanning different age groups. Data were categorized by cancer stage and treatment types. Using a cross-sectional design and correlational approach, the study found excellent reliabilities for Perceived Social Support (? = .90) and good reliabilities for Depression and Death Anxiety (? = .83 and .85, respectively). Gender-based differences were not significant for depression (t = -.51, p &gt; .05) or perceived social support (t = -.23, p &gt; .05). Perceived social support was highest initially and declined as cancer progressed. Significant variance in social support was observed across cancer stages (p &lt; .05), with post hoc tests showing that 1st stage patients had significantly higher support than 2nd, 3rd, and 4th stage patients (MD = 7.27, p = 0.09). The study also showed gender differences in death anxiety, suggesting that women exhibited higher levels of death anxiety compared to men. Moreover, perceived social support was high at the 1st stage and significantly declined as the level progressed (3rd stage). The findings can be helpful for health professionals, psychologists and caregivers.  

Correction of student’s psycho-emotional state using athletic gymnastics

The psycho- emotional state is one of the main factors affecting a person's life, as it can lead to both an increase in tone and a decline in vitality. The general psycho-emotional state consists of many factors, including well-being, activity and mood. An active movement regime accelerates the process of acquiring psychological stability and adaptation to professional activity, significantly improves the general condition and well-being of a person, and increases his work capacity and the ability to resist fatigue. All this allows us to believe that the development and substantiation of pedagogical conditions, the system of athletic gymnastics tools for the program of correction of the psycho-emotional state of student youth before educational activities is a modern and relevant research. The purpose of the study: to theoretically substantiate and empirically investigate the psycho-emotional state of student youth, to develop and implement a method of training in athletic gymnastics aimed at correcting a negative psycho-emotional state. Methodology: The research was conducted in two stages. At the 1st stage, research methods were used to solve the tasks: psychological and pedagogical observation - with the aim of finding out the motivation of student youth to achieve success in activities; survey; methods of psychological diagnosis "Self-assessment of mental states" by H. Eysenka - to determine indicators of students' mental states (anxiety, frustration, aggressiveness, rigidity); the method of research of emotional intelligence of N. Hall - to determine indicators and level of development of emotional intelligence among student youth. At the II stage, the following methods were used: questionnaires; anthropometric measurements; medical and pedagogical observation (pulsometry, tonometry, functional tests); movement test methods, N. Hall's emotional intelligence research method, and the Hot Iron strength gymnastics method. Conclusions. The conducted research makes it possible to state that the proposed method of psycho-emotional correction of negative states of student youth using cardio-strength training proved to be effective both in improving the psycho-emotional state and in physical training and in indicators of functional state, contributes to the formation of a healthy lifestyle, increases motivation for physical education.

Enhanced fluid mixing using a novel multi-stage static pipeline mixer: Numerical simulation and mechanism analysis

Static pipeline mixers play a crucial role in water treatment processes, and their mixing efficiency can be influenced by factors. Innovating mixer design to simultaneously reduce head loss and G-values while maintaining effective mixing across various flow conditions holds practical significance for improving treatment process performance. This study used a combination of numerical simulations and experimental validation to investigate the mixing process of a novel multi-stage static pipeline mixer. The results indicated that within the flow velocity range of 0.2–1.8 m/s, compared to the Kenics mixer, the new multi-stage static pipeline mixers (HOCM and COCM) achieved significant reductions in head loss (89.4 % for HOCM and 52.9 % for COCM) and G-values (67.3 % for HOCM and 31.3 % for COCM). The turbulent kinetic energy intensity of HOCM was much lower than that of COCM and Kenics mixers. Importantly, all mixers reached a state of complete mixing with the coefficient of variation (CoV) less than 0.05. In the HOCM mixer, the 2nd mixing stage was identified as the primary mixing zone, while in the COCM mixer, the 1st mixing stage played a crucial role in mixing. When the mixers achieved a mixing degree of 95 %, the head loss of HOCM and COCM was significantly lower than various types of traditional mixers (Kenics, SMX, SMV, ISG, Inliner Lightnin). This is attributed to the highly efficient mixing effect generated by the clockwise helical flow produced in the 1st and 2nd mixing stages.

The effect of knee replacement on renal function in patients with hypertension and type 2 diabetes mellitus

Objective: to evaluate the effect of knee replacement on kidney function in patients with hypertension and type 2 diabetes mellitus. Materials and methods: at stage 1, 308 people suffering from hypertension (GB), stage III osteoarthritis of the knee joint (OA CS), type 2 diabetes mellitus (DM) were examined. GB occurred in 308 people, DM — in 66 people, and OA CS — in 216 people. Depending on the presence of OA CS, observation and comparison groups were identified. Within each group, subgroups are distinguished by the presence of SD: subgroup 1 (n=170)  — OA CS +GB, subgroup 2 (n=46) — OA CS+GB+SD, subgroup 3 (n=72) — GB, subgroup 4 (n=20) — GB+SD. At stage 2, the dynamics of GFR after total knee arthroplasty (TEP CS) in subgroups 1 and 2 and against the background of AGT therapy in subgroups 3 and 4 were evaluated. Results: at the 1st stage, it was found that the proportion of people with GFR 60 ml/min/1.73 m2 was significantly higher in subgroup 1 (OA CS+GB) compared with subgroup 3 of patients with GB without joint pathology (40.6% vs. 12.5%, p0.01). The presence of DM in patients with GB significantly affected renal filtration function, which is reflected in an increase in serum creatinine levels in subgroup 4 (GB+DM) by 20.02% and a decrease in GFR by 15.35%.Against the background of the performed TEP in the group with GB, 64.06% had a stable GFR value or its increase, and in the subgroup of GB+ DM after TEP, 72.41% of patients had an increase or stable state of renal filtration capacity. At the same time, during the same follow-up period in the comparison group (in patients with GB without comorbid conditions), only 39.13% of cases had stable GFR values, and a decrease in GFR was recorded in 60.87%. At the same time, the dynamics of GFR values manifested itself in an increase of 11.19% in patients of subgroup 5 (TEP CS + GB) and by 12.47% in the group of the described knee joint intervention with a combination of GB and DM. In patients with controlled hypertension, GFR decreased by 6.6%. Conclusion: knee replacement in patients with hypertension and type 2 diabetes mellitus can slow down the rate of GFR reduction.

Low cycle fatigue behavior and life prediction of a directionally solidified alloy

Alloys used in engines are subjected to challenging environments characterized by thermal and mechanical cyclic loadings during start-up and shut-down processes. These conditions can significantly increase the occurrence of fatigue failure mechanisms. Therefore, this study focuses on investigating the low cycle fatigue (LCF) behavior of directionally-solidified alloy at two distinct temperatures, namely 600 °C and 800 °C. Strain-controlled LCF tests were conducted at the specified temperatures, utilizing constant total strain amplitudes of 0.4%, 0.6%, 0.8%, and 1% under a totally reversed loading ratio (R = -1). The Coffin-Manson model, based on plastic deformation, along with a hysteresis energy-based criterion model, were employed to predict and evaluate fatigue life and LCF behavior. Notably, the hysteresis energy and Coffin-Manson models exhibited superior capability in predicting LCF life at 800 °C compared to 600 °C.   REFERENCES Salehnasab, J. Marzbanrad, E. 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Failure analysis of gas turbine in first stage turbine blades in an urban power plant

The Combined Cycle Power Plants (CCPP) are widely known as the most efficient power plants. The concept of CCPP represented in Brayton and Rankin cycles combined to achieve the highest efficiency in power generation. During the fact finding, while performing the major outage, at 77,521 running hours some of the turbine blades at 1st stage found suffering from severe damages and sulfuric acid thick layer accumulated in the cooling airfoils. The blades were new, also known as the most essential and costly component installed after Hot Gas Path Inspection (HGPI) at 42,000 running hours. The main objective of this work is to study the surrounding parameters that directly affect the lifetime of the turbine blades. Furthermore, XRD analysis for new and used turbine blades are studied as well as the EDS analysis for the coating layers which are used to enhance the surface life of gas turbine blades. Corrective maintenance, on the other hand, has been undertaken to overcome the performance deterioration caused by wear, which is the result of any machine or plant’s operation. A gas turbine cannot be run reliably unless wear reserves are checked and, if necessary, restored during inspections and maintenance operations. These are performed to determine the machine's condition and the necessary condition-based repairs. The principal types of gas turbine inspection have been investigated and presented, including minor inspection, hot gas inspection, extended-scope hot gas path examination, and major inspection. Lifetime extension (LTE) measures are derived from these inspection types and go beyond the scope of a major inspection. Nondestructive testing is performed on the gas turbine’s key components. Furthermore, due to the high degree of contamination in the fuel, the turbine section must be cleaned at regular intervals. As a result of the examinations, replacement, and refurbishment intervals for important components, as well as outage time, could be recommended.

The effect of particle geometry (size & shape) on the recovery of gold and copper metallic particles from end-of-life random access memory cards by flotation

Since Random Access Memory (RAM), one of the main parts of computers contains a remarkable quantity of precious metals, applying flotation at the pre-concentration stage to recycle these metals can result in a more cost-effective, user-friendly, and environmentally friendly process compared to direct chemical methods. While the significance of physical characteristics like particle size and shape in the flotation process is well established, the impact of particle shape in the flotation process utilized in the recycling of end-of-life (EoL) RAMs hasn’t yet been thoroughly investigated. To fill this gap, a two-stage coarse flotation approach is used for the selective recovery of plastic and valuable metallic particles for sustainable development. The particle geometry of metallic particles recovered by flotation was characterized by axis measurement on the images by optical microscope that allows us to distinguish particles of different sizes and colors that make up the sample and evaluated in terms of particle size distribution (PSD), elongation (E) and roundness (R) parameters. The results showed that after the plastic fraction is effectively removed, it is possible to produce pre-concentrated products with high metal content (more than 50 % Cu content at the 1st stage and 1800 g/t Au content at the 2nd stage using 900 g/t KAX) in an economical and environmentally friendly way. Thus, it was concluded that the gold and copper metallic particles in the reduced-size EoL RAM cards could be easily floated by attaching them to the air bubble with the help of the collector, thanks to their flat shape.