Search Results (1,423)

Background: The aim of this study is to investigate the effect of topical ice slush on cardiac protection in patients undergoing cardiac surgery and to analyze its potential side effects. Methods: Between 2023 and 2024, 890 patients who underwent cardiac surgery were evaluated. The patients were divided into two groups: Group A (n = 549), assigned ice slush(+), and Group B (n = 341), assigned ice slush(−). Echocardiographic findings, laboratory parameters, arterial blood gas findings, inotrope requirements, and postoperative outcomes were compared. Patients with a left internal thoracic artery were excluded from this study, and new subgroups were created as follows: Group C (n = 235), assigned ice slush(+), and Group D (n = 111), assigned ice slush(−). Chest radiography and diaphragm elevations (DEs) were compared at the 12-month follow-up. Results: No significant differences were found between the groups in terms of demographic characteristics, comorbidities, and operative data. The postoperative echocardiographic findings and ABG findings were similar. The inotrope requirement was higher in Group A. Postoperative day 1 Troponin T was higher in Group A than in Group B (median: 561–473 ng/mL, p = 0.01). The postoperative outcomes were similar between the groups, except that the intubation duration was longer in Group A. In the 1st postoperative week, 199 (36.2%) patients in Group A and 127 (37.2%) patients in Group B had DE. In the 12th month postoperation, 20 (3.6%) patients in Group A and 12 (3.5) patients in Group B had DE. Although not statistically significant, the incidence of DE was higher in Group C than in Group D in the early postoperative period only. Conclusions: We found no additional cardioprotective benefit from the use of topical ice slush in cardiac surgery. The intubation time was longer in patients with topical ice slush than in patients without it. Our results suggest that the routine use of topical ice slush in cardiac surgery is not necessary and that it has potential adverse effects. Full article

Background/Objectives: Patients with advanced ovarian cancer with a high tumor burden typically undergo neoadjuvant chemotherapy (NACT) followed by interval debulking surgery. The optimal number of NACT cycles remains undefined: although three to four cycles are considered gold-standard, in real-world practice, five or more cycles are frequently administrated. This study aims to evaluate the impact of delayed interval debulking surgery (DIDS) after ≥5 cycles of NACT on the survival rates. Methods: We conducted a retrospective analysis of women with advanced ovarian cancer that underwent surgery in the 1st Department of Obstetrics–Gynecology Clinic from 2012 to 2022. Patient characteristics, oncological, and follow-up information were collected. Results: A total of 125 patients met the inclusion criteria and were divided into two groups: Group A (77 patients) received 3–4 of NACT cycles, and Group B (48 patients) ≥5 cycles. No statistically significant difference was observed between the groups concerning age, BMI, comorbidities, Aletti score, FIGO stage, pre-operative CA-125 values, surgery duration, rate of postoperative complications, hospital stay, ICU admittance, and complete gross resection (RD = 0). However, patients undergoing DIDS experienced significantly greater intraoperative blood loss. Progression-free survival did not differ between groups (IDS: 17 vs. DIDS: 18 months, p = 0.561), whereas overall survival was significantly lower in the DIDS group (IDS: 52 vs. DIDS: 36 months, p = 0.00873). This statistical significance persisted after controlling for residual disease, but was lost after adjusting for FIGO stage. Conclusions: DIDS may be considered for advanced ovarian cancer patients with a high tumor burden, when complete gross resection (RD = 0) cannot be achieved during IDS. Further prospective randomized trials are necessary to evaluate its oncological safety and morbidity. Full article

This research explores a phase-shift-based discontinuous PWM method used for 24 V battery-powered onboard micro inverters, which are critical for thermally limited applications like micromachines, where efficient heat dissipation and compact size are paramount. Discontinuous pulse width modulation (DPWM) reduces switching losses by clamping the phase voltage to the DC bus in order to improve inverter efficiency. Due to the change in power factor at different operating points from motors or the inductor load, the use of only one DPWM method cannot achieve the optimal efficiency of a three-phase voltage source inverter (3ph-VSI). This paper proposes a generalized DPWM method with a continuously adjustable phase shift angle, which extends the six traditional DPWM methods to any type. According to different power factors, the proposed DPWM method is divided into five power factor angle intervals, namely [−90°, −60°], [−60°, −30°], [−30°, 30°], [30°, 60°], and [60°, 90°], and automatically adjusts the phase shift angle to the optimal-efficiency DPWM mode. The power factor is calculated by means of the Synchronous Reference Frame Phase-Locked Loop (SRF-PLL) method. The switching losses and harmonic characteristics of the proposed DPWM are analyzed, and finally, a 24 V onboard 3ph-VSI experimental platform is built. The experimental results show that the efficiency of DPWM methods can be improved by 3–6% and the switching loss can be reduced by 40–50% under different power factors. At the same time, the dynamic performance of the proposed algorithm with a transition state is verified. This method is particularly suitable for miniaturized inverters where efficiency and thermal management are critical. Full article

Objective: Type B aortic dissection is a life-threatening medical condition. Endovascular closure of the primary entry by means of TEVAR is considered, nowadays, the gold standard if operative treatment is necessary. The aim of this study is to analyse the theoretical applicability of selective endovascular entry sealing using different occluder systems. Methods: A CT-graphic analysis of 102 patients who received TEVAR from January 2017 to June 2023 was performed. Patients with an intramural haematoma were excluded. The study patients were divided in two groups: type B aortic dissection (n = 87) and distal stent graft-induced new entry (n = 15). The TBAD group included patients with acute (n = 63), subacute (n = 12), and chronic aortic dissections (n = 12). The CTA analysis of the location, length, and width of the entry was performed using Aquarius iNtuition (TeraRecon, Inc., Foster City, CA, USA). After completion of the data collection, the possible application of all three occluder systems (ASD-Occluder, Septal-Occluder, and Amplatzer™-Occluder) was analysed, with reference to the Instructions for Use. Results: The ASD-Occluder from GORE is produced in five different sizes. It can be used in 81.4% (n = 83) of all patients in the overall study, including 82.8% TBAD (n = 72) and 73.3% of dSINE (n = 11) patients. When using the ASD-Occluder, 10.3% (n = 9) of patients are expected to have complete vascular coverage of the LSA based on our CTA analysis. The Septal-Occluder from GORE is offered in three different sizes. Complete entry closure can theoretically be achieved in fifty patients (57.5%) with TBAD and in nine patients (60%) with dSINE, based on CTA analysis and IFU criteria. With the use of the Septal-Occluder, 3.9% (n = 4) of the dSINE patients and 4.6% (n = 4) of the TBAD patients were expected to have complete aortic branch occlusion. The Amplatzer™-Occluder from Abbott is provided in 27 different sizes to effectively seal defects with a diameter of 4 to 56 mm. It can technically be used in 90.1% of patients (n = 92), of which 89.7% with TBAD (n = 78) and 93.3% with dSINE (n = 14) to completely seal the entry. Conclusions: CTA analysis in patients with TBAD and dSINE demonstrated that by the theoretical application of occluder systems, a seal of the entry would be achieved in 57.8% to 90.1% of the patients. However, in addition to entry closure, the use of occluder systems can also lead to unintentional partial (10.7–23.5%) or complete (3.9–22.5%) coverage of adjacent aortic branches. The clinical significance and applicability of the occluder system should be reviewed in future studies and practical applications to evaluate safety, efficacy, and possible complications in order to define the benefit–risk balance. Full article

In many countries, most one-phase residential electricity consumers are supplied from three-phase, four-wire local networks operated in radial tree-like configurations. Uneven consumer placement on the wires of the three-phase circuit leads to unbalanced phase loads that break the voltage symmetry and increase the energy losses. One way to mitigate these problems is to balance the phase loads on the feeders by choosing the optimal phase of connection of the consumers. The authors proposed earlier a phase balancing algorithm based on metaheuristic optimization. For networks with a high number of supply nodes, this algorithm requires finding a solution for all the consumers simultaneously. Two alternative approaches are proposed in this paper that use the tree-like structure of the network to divide the optimization between a main distribution feeder and several branches, creating a multistage process, with the aim of minimizing energy losses. A case study is performed using a real low-voltage distribution network and a comparison is made between the three algorithms. The resulting losses have marginal variations between the proposed approaches, with a maximum of 1.3% difference. Full article

Background and Objectives: Performance of robot-assisted total knee arthroplasty (TKA) procedures has continued to increase in popularity. However, tourniquet use is necessary for longer periods of time in robot-assisted TKA than conventional manual TKA because the robot-assisted procedure requires an additional registration process. The use of tourniquets for long periods increases the risk of hidden blood loss and ischemic soft tissue injury in the lower extremity. The purpose of this study was to compare the value of performing robot-assisted TKA without the use of a tourniquet to that of performing this surgery with the use of a tourniquet. Parameters we assessed were blood loss, degree of postoperative thigh and knee pain, and occurrence of early post-operative complications. Materials and Methods: Data from 100 consecutive patients who underwent primary unilateral robot-assisted TKA between July 2024 and July 2025 were included in this study’s analyses. Patients were divided into three groups chronologically. The first 29 patients comprised group 1, the early tourniquet group; the next 30 patients were assigned to group 2, the no tourniquet group; and group 3 was the late tourniquet group and comprised the remaining 41 subjects. However, because allocation was chronological rather than randomized, the outcomes of later groups may partly reflect the surgeon’s accumulated experience (learning curve), which should be considered when interpreting the results. The primary outcome measure was estimated blood loss (EBL). The secondary outcome measures included transfusion rate, visual analog scale (VAS) pain scores for the knee and thigh on the third postoperative day, readmission rate due to surgical complications, superficial and deep infection rate, length of operation, and length of tourniquet use. Results: Group 2 participants, the no tourniquet participants, experienced significantly greater EBL on postoperative days (PODs) 1, 2, and 3 compared to the subjects assigned to groups 1 and 3 (p = 0.003, p < 0.001, and p = 0.005, respectively). However, there were no significant differences in transfusion rates (p = 0.290) among the 3 groups. VAS scores for knee and thigh pain were also not significantly different among the three groups (all p-values > 0.05). Three patients in group 1 (10.3%), one patient in group 2 (3.3%), and one patient in group 3 (2.4%) were readmitted for complications related to wound healing (p = 0.289). Additionally, two patients in group 1 developed superficial wound infections from which the causative bacteria were cultured. No infections were observed in the other groups (p = 0.082), however. Two patients in group 1 and two patients in group 2 experienced symptomatic deep vein thrombosis (DVT) (p = 0.235). No group 3 patients experienced DVT, and only one patient in group 2 was confirmed with DVT using an enhanced CT scan (p = 0.308). Group 3 patients had shorter lengths of surgery (p < 0.001) than group 1 and 2 patients and had shorter periods of tourniquet use (p = 0.034) than group 1 patients. Conclusions: Tourniquet non-use in robot-assisted TKA surgeries was associated with greater EBL in acute postoperative periods, but this finding was not accompanied by any change in transfusion rate. Tourniquet non-use was not clinically beneficial for reducing immediate postoperative thigh and knee pain or reducing the prevalence of early post-operative complications. Tourniquet use in robot-assisted TKA may be beneficial because of the advantages its use provides in maintaining a clear surgical field and in facilitating the cementing process. Full article

Addressing the problems of wind power’s anti-peak regulation characteristics, increasing system peak regulation difficulty, and wind power uncertainty causing frequency deviation leading to power imbalance, this paper considers the peak shaving and valley filling function and frequency regulation characteristics of energy storage, establishing a day-ahead and intraday coordinated two-stage optimization scheduling model for research. Stage 1 establishes a deterministic wind power prediction model based on time series Autoregressive Integrated Moving Average (ARIMA), adopts dynamic peak-valley identification method to divide energy storage operation periods, designs energy storage peak regulation working interval and reserves frequency regulation capacity, and establishes a day-ahead 24 h optimization model with minimum cost as the objective to determine the basic output of each power source and the charging and discharging plan of energy storage participating in peak regulation. Stage 2 still takes the minimum cost as the objective, based on the output of each power source determined in Stage 1, adopts Monte Carlo scenario generation and improved scenario reduction technology to model wind power uncertainty. On one hand, it considers how energy storage improves wind power system inertia support to ensure the initial rate of change of frequency meets requirements. On the other hand, considering energy storage reserve capacity responding to frequency deviation, it introduces dynamic power flow theory, where wind, thermal, load, and storage resources share unbalanced power proportionally based on their frequency characteristic coefficients, establishing an intraday real-time scheduling scheme that satisfies the initial rate of change of frequency and steady-state frequency deviation constraints. The study employs improved chaotic mapping and an adaptive weight Particle Swarm Optimization (PSO) algorithm to solve the two-stage optimization model and finally takes the improved IEEE 14-node system as an example to verify the proposed scheme through simulation. Results demonstrate that the proposed method improves the system net load peak-valley difference by 35.9%, controls frequency deviation within ±0.2 Hz range, and reduces generation cost by 7.2%. The proposed optimization scheduling model has high engineering application value. Full article

Utilizing a novel approach that concomitantly assessed cyclic fatigue and torsional overloading, we aimed to establish the maximum number of artificial canals that can be prepared by Hyflex EDM and NeoNiTi A1 operated at two different speeds until their separation. Forty-eight files were equally divided into four groups: (A) Hyflex EDM operated at 300 rotations per minute (RPM) and (B) at 500 RPM, and (C) NeoNiTi A1 at 300 RPM and (D) at 500 RPM. Files were used to completely shape 10 sequential artificial canals unless file separation occurred. Maximum number of canals prepared was noted and averaged. Fractography was conducted to determine the mechanism of file separation. Hyflex EDM prepared significantly more canals compared to NeoNiTi A1 (p = 0.008). When operated at 300 RPM, Hyflex EDM prepared significantly more canals compared to NeoNiTi A1 (p = 0.028), whereas no significant difference was observed when they were operated at 500 RPM (p = 0.116). One NeoNiTi file broke due to cyclic fatigue while another one separated due to torsional overloading. Hyflex EDM files showed signs of both mechanisms. Within the limitations of this study, one file safely prepared four to five canals before its fracture. There was a trend towards fewer prepared canals as the RPM increased. Full article

Under jamming environments, the simulation system of monopulse radar consumes substantial computational resources due to echo signal and jamming signal generation, as well as real-time radar signal processing, leading to large time consumption in evaluating the radar’s anti-jamming performance in complex electromagnetic jamming scenarios. This paper proposes a monopulse radar simulation strategy based on space slicing to improve simulation efficiency. By considering the operational characteristics of the monopulse radar, including search, acquisition, track, and narrow search modes, the space where radar and target are located is divided into discrete grid points in different granularity. The simulation results for each slice are used to replace full-process real-time signal processing, thus improving the overall efficiency of the simulation system. The estimation errors of the target’s range, velocity, and angular after space slicing are theoretically analyzed. Simulation experiments demonstrate that, by utilizing the proposed space slicing strategy, the simulation speed is improved dramatically, with target parameter estimation errors remaining relatively small compared to full-process real-time simulations. Full article

To improve the maneuverability of the installation vessel and shorten the operational timeframe, a dynamic positioning (DP) semi-submersible vessel with a sophisticated control strategy is utilized to replace the conventional traction systems and towing tugs. In this paper, an improved fuzzy control law is developed for the standby and docking stage of the float-over installation. The control thrust is divided into a dynamic part and a static part. Both parts are computed based on a set of logical if–then-type statements based on the human sense of realism and expert experience. The dynamic part acts as the proportional–derivative control, while the static part contributes the integral action. The implementation of accumulation time enhances the static thrust’s effectiveness in positioning the vessel compared to traditional integral control methods. A model test is further conducted to validate the effectiveness of the proposed improved fuzzy control based on a DP barge. Wind, wave, and current are considered from different directions in the experiment to simulate the practical operation condition. Experimental results illustrate that the proposed improved fuzzy control law can accurately keep position and guide the vessel into the slot of the jacket. Finally, some conclusions are summarized for the characteristic of fender forces in different environmental load directions. Full article

Objectives: This study examines the influence of the uterine wall region from which a tumor originates on the prognosis of endometrial cancers (ECs) originating from the uterine corpus without lower uterine segment involvement (LUSI). Methods: This study included 68 EC patients who were operated on between January 2015 and January 2022 and met the following criteria: no LUSI noted in the final pathology report; endometrioid adenocarcinoma originating from the uterine corpus, as noted in the histopathology report; and Stages 1A and 1B tumors, classified according to the FIGO 2009 staging system. From the final pathology results after the operation, these patients were divided into four groups according to the uterine wall region from which the tumor originated: the anterior wall, posterior wall, fundus, and lateral wall. Results: No statistically significant difference was recorded between the groups regarding age, BMI, comorbidity, nulliparity, stage, grade, tumor size, DFS, and OS (p > 0.05). LVSI was detected at a higher rate in the anterior and posterior wall groups than in the fundus and lateral wall groups (p = 0.038). Similarly, the rates of recurrence and death were statistically notably higher in the anterior and posterior wall groups in comparison with those in the other two groups (p < 0.001). Conclusions: In endometrioid adenocarcinomas of the uterine corpus, tumors originating from the anterior and posterior walls have a worse prognosis than those originating from the fundus and lateral wall. Closer follow-up may be necessary for endometrial cancers originating from the anterior and posterior uterine walls. Full article

Climate change and labour shortage are re-shaping farming methods. Agricultural tasks are often hard, tedious and repetitive for operators, and farms struggle to find specialized operators for such works. For this and other reasons (i.e., the increasing costs of agricultural labour) more and more farmers have decided to switch to autonomous (or semi-autonomous) field robots. In the past decade, an increasing number of robots has filled the market of agricultural machines all over the world. These machines can easily cover long and repetitive tasks, while operators can be employed in other jobs inside the farms. This paper reviews the current state-of-the-art of autonomous robots for agricultural operations, dividing them into categories based on main tasks, to analyze their main characteristics and their fields of applications. Seven main tasks were identified: multi-purpose, harvesting, mechanical weeding, pest control and chemical weeding, scouting and monitoring, transplanting and tilling-sowing. Field robots were divided into these categories, and different characteristics were analyzed, such as engine type, traction system, application field, safety sensors, navigation system, country of provenience and presence on the market. The aim of this review is to provide a global view on agricultural platforms developed in the past decade, analyzing their characteristics and providing future perspectives for next robotic platforms. The analysis conducted on 59 field robots, those already available on the market and not, revealed that one fifth of the platforms comes from Asia, and 63% of all of them are powered by electricity (rechargeable batteries, not solar powered) and that numerous platforms base their navigation system on RTK-GPS signal, 28 out of 59, and safety on LiDAR sensor (12 out of 59). This review considered machines of different size, highlighting different possible choices for field operations and tasks. It is difficult to predict market trends as several possibilities exist, like fleets of small robots or bigger size platforms. Future research and policies should focus on improving navigation and safety systems, reducing emissions and improving level of autonomy of robotic platforms. Full article

Background: Intensive Care Units (ICUs) provide critical support for patients after major surgery or acute abdominal conditions. Despite medical advances, mortality remains high in surgical ICU patients. This study aimed to identify clinical and biochemical predictors of mortality in surgical patients admitted to a tertiary ICU. Methods: We conducted a retrospective case–control study on 231 adult general surgery patients admitted to a tertiary anesthesia ICU between January 2018 and December 2023. Patients under 18 years or who underwent solid organ transplantation were excluded. Data collected included demographic, clinical, and laboratory parameters such as the Glasgow Coma Scale (GCS), Acute Physiology and Chronic Health Evaluation II (APACHE II), Sequential Organ Failure Assessment (SOFA), Hemoglobin-Albumin-Lymphocyte-Platelet (HALP) score, neutrophil-to-lymphocyte ratio (NLR), and C-reactive protein (CRP)/albumin ratio. Patients were divided into mortality and survival groups, with subgroup analyses performed for malignancy, sepsis, and trauma. Receiver operating characteristic (ROC) curve and Cox regression analyses were used to identify mortality predictors. Results: The ICU mortality rate was 64.9%. Significant predictors included age ≥ 58 years (odds ratio [OR] 4.56), body mass index (BMI) > 30 kg/m² (OR 7.62), mean arterial pressure < 70 mmHg (OR 1.66), serum albumin < 21.3 g/L (OR 1.5), APACHE II > 18.5 (OR 2.42), and SOFA > 9.5 (OR 2.68). Mortality was also associated with lower GCS scores, prolonged mechanical ventilation, and inotropic support. The CRP/albumin ratio was significantly elevated in the mortality group (p = 0.024). Other inflammatory markers showed no significant differences. Predictive factors varied among subgroups. Conclusions: Older age, obesity, hypotension, hypoalbuminemia, and high severity scores independently predict mortality in surgical ICU patients. Early risk identification may enhance management and improve outcomes in this population. Full article

Background/Objectives: Cytoreductive surgery for women with advanced ovarian cancer is a demanding process with high morbidity. The present analysis aims to identify whether using the Ligasure^® Maryland jaw open sealer/divider (LMJsd) with a nanocoating (Covidien^®, Medtronic^®, 710 Medtronic Parkway, Minneapolis, MN, USA), could lead to better outcomes during cytoreduction surgery by reducing intraoperative bleeding and other hospitalization-related parameters. Methods: Patients with ovarian cancer (FIGO III/IV) who were subjected to primary or interval cytoreductive surgery at the Gynecologic-Oncology Unit, 1st Department of Obstetrics and Gynecology, Papageorgiou General Hospital, Thessaloniki, Greece, were included in the analysis. Patients were retrospectively allocated into two groups: women operated on with or without using the LMJsd. Differences between the two groups (intraoperative blood loss and blood transfusion, duration of surgery, postoperative blood transfusion, admission to intensive care unit (ICU), and overall hospital length of stay) were investigated. Results: From 2012 to 2020, 284 women with ovarian cancer were surgically treated; 208 were stage III/IV. In the LMJsd group of women (n = 34), the duration of surgery and blood loss during surgery were significantly decreased (p < 0.0005) compared to the non-LMJsd group (n = 174). The intraoperative blood transfusion rate and the number of packed red blood cell units transfused were significantly decreased in the first group (p = 0.0025); the postoperative blood transfusion rate was not different (p = 0.065). Moreover, ICU admission and overall hospital length of stay were significantly decreased in the LMJsd group (p < 0.0005 and p = 0.015). Conclusions: Using the LMJsd is associated with decreased intraoperative bleeding and transfusion rates, duration of surgery, admission to ICU, and overall hospital length of stay in women treated with surgical cytoreduction for advanced ovarian cancer. Some limitations of this study are as follows: its limited impact because it is an observational retrospective analysis and bias because the cumulative experience of the surgeons may have an impact on the surgical outcomes. Full article

Objectives: The present study mainly aimed to identify whether the envelope and triangular flaps affected wound healing and patient quality of life differently. Secondarily, the study aimed to investigate whether some anatomical and operational variables may also affect healing. Study design: A prospective randomized study was conducted with 56 fully impacted lower third molars, randomly divided into two groups, one treated with the envelope flap and the other with the bayonet flap. Qualitative variables were transformed into quantitative ones and then analyzed using independent samples t-tests or analysis of variance. An analysis of bivariate correlations with Pearson’s coefficient was also used. The chi-square test was used to verify the association between each flap and the categorical variables considered. Results: No statistically significant associations were found between flap types and dehiscence, although the mean dehiscence diameter was consistently greater in the envelope flap group. The maximum diameter of the dehiscence at 14 days was found to be significantly and negatively related to the 14-day wound healing indices. Analyses relating to the quality of life did not show significant associations. Conclusions: Despite some significant healing differences between the two considered flaps exist, they do not have relevant effects on the patient’s post-operative quality of life. Full article