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Data background: Because the traditional open-TLIF approach has several drawbacks, minimally invasive surgery (MIS) approaches for TLIF (MISTLIF) have been developed to speed up recovery after surgery and minimize pressure on the para-spinal muscles, necessitating a cost-utility analysis for comparison in healthcare reforms. Objectives and aim of the work: This study aimed to compare the radiological and clinical parameters between mini-open TLIF and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) surgery in patients with single-level lumbar degenerative spondylolisthesis. Hypothesis: This study hypothesizes that both minimally invasive and mini-open methods using sublaminar trimming laminoplasty (SLTL) (while preserving midline structures) and interbody cages have comparable mid- and long-term clinical and radiological outcomes. Methods: Retrospective analyses were performed on 120 patients who underwent single-level TLIF procedures with a minimum of two years of follow-up utilizing either the mini-open (n = 60) or MIS (n = 60) technique. Records of the operation's time frame, intraoperative fluoroscopy, blood loss, postoperative drainage volume, duration of bed rest, and complications were recorded. The Oswestry Disability Index (ODI) and visual analog scale (VAS) scores for both groups were utilized to assess improvements in clinical scores, and t tests were employed to statistically compare the outcomes. For comparison, radiological parameters, including lumbar lordosis, pelvic incidence (PI), and localized lordosis at the index level, were measured preoperatively, postoperatively, and at the final follow-up. To assess postoperative interbody fusion, the Bridwell grading system was used. Results: In the Mini-open TLIF group, the average follow-up time was 24.91 ± 5.7 months, while in the MIS-TLIF group, the average follow-up time was 25.15 ± 4.2 months. In the MIS-TLIF group, the mean operation and radiological time were longer. However, compared to the Mini-open TLIF group, the MISTLIF group experienced less blood loss and a shorter hospital stay. The MIS-TLIF group outperformed the Open-TLIF group in terms of the VAS score for back pain and the ODI at less than 6 months following surgery, and the differences were statistically significant. However, at the final follow-up, there were no statistically significant differences in the VAS score for the back between the two groups, but the ODI score was significantly greater in the MIS-TLIF group. Both groups' lumbar lordosis and focal lordosis significantly improved at the index level, with the Mini-open-TLIF group showing more focal lordosis. The interbody fusion rate did not significantly differ between the two groups. Conclusion: MIS-TLIF and mini-open-TLIF can be surgically effective in treating single-level degenerative lumbar spine spondylolisthesis. [ABSTRACT FROM AUTHOR]

The interaction between the wind farm and the series‐compensated transmission line may lead to the sub‐synchronous oscillation (SSO) phenomenon which affects the system stability and equipment safety. Among the presented methods for damping the SSO phenomenon, the supplementary damping controller (SDC) is the most prevalent method because of its low cost, effectiveness, and simplicity. In all previous studies, one input control signal is fed to the SDC for mitigating the SSO. Here, two input control signals (active power and reactive power deviation) are applied to the SDC for enhancing the system stability and damping the SSO quickly. The ability of the proposed method for damping the SSO has not been investigated before. The proposed SDC is embedded into the q‐axis of the rotor‐side converter (RSC) inner current loop. The modified IEEE first benchmark model (FBM) is used to analyze the performance of the proposed method under different compensation levels, variable wind speeds, and sub‐synchronous control interaction (SSCI). Small‐signal stability using the eigenvalue approach is carried out, where the impact of the proposed method on sub‐synchronous mode, and super‐synchronous mode is investigated. The results successfully prove the superiority of the proposed method for damping the SSO under various operating conditions compared to some previous methods, where the least overshoot and faster convergence have been achieved by the proposed method in all studied cases. [ABSTRACT FROM AUTHOR]

The threshing unit is the main working unit of the combine harvester and plays an essential role in rice threshing efficiency, seed loss, and damage. Every thresher has its limitation for feeding, and when the feeding quantity exceeds the maximum rated amount, the thresher gets blocked, resulting in higher losses, low threshing efficiency, more power consumption, and combine overloading shutting down. This study constructed a longitudinal axial flow rice threshing platform, and a stress monitoring system for the threshing drum top cover was designed using force sensing resistors. The sensors were installed on the thresher top cover inner surface to detect the impact and extrusion forces caused by the threshing process and detect the feeding rate when it exceeds the suitable feeding. Three feeding rates (0.8, 1.1, and 1.4 kg/s) and three thresher speeds (1100, 1300, and 1500 rpm) were tested. The time of the testing process was calculated using high-speed photography. The obtained results revealed that the force signals collected by thin-film sensors significantly correlated with thresher rotating speed and feeding rate. The thresher top cover's average stress, average strain, and average total deformation were simulated using ANSYS finite element analysis. This study provides a new method for threshing drum real-time feeding quantity monitoring and early warning of thresher blockage. [ABSTRACT FROM AUTHOR]

Background: There have been few published reports on severe Plasmodium falciparum and Plasmodium vivax malaria among adults in Africa. Methods: Clinical pattern/manifestations of severe P. falciparum and P. vivax (according to World Health Organization 2000 criteria) were described in adult patients admitted to Kassala Hospital, eastern Sudan. Results: A total of 139 adult patients (80 males, 57.6%) with a mean (SD) age of 37.2 (1.5) years presented with severe P. falciparum (113, 81.3%) or P. vivax (26, 18.7%) malaria. Manifestations among the 139 patients included hypotension (38, 27.3%), cerebral malaria (23, 16.5%), repeated convulsions (18, 13.0%), hypoglycaemia (15, 10.8%), hyperparasitaemia (14, 10.1%), jaundice (14, 10.1%), severe anaemia (10, 7.2%), bleeding (six, 4.3%), renal impairment (one, 0.7%) and more than one criteria (27, 19.4%). While the geometric mean of the parasite count was significantly higher in patients with severe P. vivax than with severe P. falciparum malaria (5,934.2 vs 13,906.6 asexual stage parasitaemia per μL, p = 0.013), the different disease manifestations were not significantly different between patients with P. falciparum or P. vivax malaria. Three patients (2.2%) died due to severe P. falciparum malaria. One had cerebral malaria, the second had renal impairment, jaundice and hypoglycaemia, and the third had repeated convulsions and hypotension. Conclusions: Severe malaria due to P. falciparum and P. vivax malaria is an existing entity among adults in eastern Sudan. Patients with severe P. falciparum and P. vivax develop similar disease manifestations. [ABSTRACT FROM AUTHOR]

Optimal Reactive Power Dispatch (ORPD is thought of as a noncontinuous, nonlinear global optimization problem. Within the system's constraints, the ORPD manages to accomplish the reactive power flow. Due to its more intricate linkage of variables, the reactive power issue is more challenging to resolve than the optimum power flow issue. With the existence of renewable energy resources (RERs), solving the ORPD problem to attain the most stable and secure system condition has become a more challenging task. The goal of this article is to solve the objective function of ORPD combined with RERs using a metaheuristic novel optimizer named the African Vultures Optimization Algorithm abbreviated by (AVOA), where the formulation of the ORPD issue including minimization of three single objective functions as follows, voltage deviation, system operating cost, and real power loss, is introduced and also transmission power loss minimization is embraced with the simultaneous incorporation of the optimal renewable energy resources (RERs). Where the ORPD problem complexity grows exponentially with a mixture of continuous and discrete control variables, two distinct continuous and discrete types of optimization variables are considered, and the proposed single objective functions that meet different operating constraints are then transformed into a coefficient multi-objective ORPD problem and elucidated using the weighted sum approach. To validate the suggested algorithm's effectiveness in addressing the ORPD issue, it is evaluated on three standard IEEE networks: the IEEE-30 bus small-scale network, the IEEE-57 bus medium-scale network, and the IEEE-118 bus large-scale network using different scenarios and the outcomes are compared to these other popular optimization techniques. The findings show that the suggested AVOA algorithm provides an efficient and sturdy high-quality solution for tackling ORPD situations and vastly enhances the overall system performance of power at all scales. [ABSTRACT FROM AUTHOR]

• An improved method for detecting the subsynchronous oscillation (SSO) is proposed. • Both the first-order BPF and stability criterion are used for avoiding the erroneous judgment. • The simulation results prove the speed and accuracy of the improved SSO detection method. The use of series capacitors in long distance transmission lines leads to subsynchronous oscillation (SSO), which affects the stability and safety of power systems. The accurate detection of the SSO phenomenon within a short time is a necessary to avoid the harmful effects of SSO on power systems. This paper first presents an overview of previous SSO detection methods. An effective, secure, and improved SSO detection method based on the voltage signal is proposed and consists of two stages, namely, analysis and decision. In the analysis stage, the voltage magnitude signal passes through a first-order bandpass filter (fast filtration in the time domain) to only pass the subsynchronous frequency, and a new method for detecting the oscillation is added to avoid erroneous judgments and to make the method secure. In the decision stage, the best decision is taken (SSO detection, instant trip, or normal trip) based on the received data from the analysis stage. The robustness and speed of the improved SSO detection method are tested with the induction generator effect (IGE), subsynchronous control interaction (SSCI), and torsional interaction (TI). Simulation results indicate that the improved method can effectively and quickly detect the SSO phenomenon. The improved method is compared with the traditional method with different SSO types (IGE, TI, and SSCI) and is proven to be faster than the traditional method in all cases. In this study, the IEEE first benchmark model is adapted with a doubly fed induction generator (DFIG) wind farm to study the SSO phenomenon. MATLAB/SIMULINK software is used to validate the results. [ABSTRACT FROM AUTHOR]

Several studies highlighted that the surface shape modifications which are inspired by the soil-burrowing animals have positively impacted the soil-tool adhesion; however, it is still unclear what the optimum dimensions of the domed surface are for minimizing soil-tool adhesion. In this study, twenty-seven domed discs were created according to Taguchi orthogonal array L27(3³) to determine the optimum dimensions of the domed surface that minimize normal adhesion force and disc sinkage simultaneously, as well as comparing the effect of the optimized domed disc versus the flat disc on the normal adhesion force under different soil conditions. The results revealed that disc coverage ratio and dome height to diameter ratio are essential to design parameters that influence the normal adhesion force of discs. According to the signal-to-noise ratio analysis, it was observed that the combination of 60% disc coverage ratio, 25% dome height to diameter ratio, and 10 mm dome base diameter was found to be the most appropriate for the well-balanced improvement of both normal adhesion force and disc sinkage simultaneously. In all treatments, the optimized domed disc produced less normal adhesion force than the flat disc (about 7%-18%, according to soil condition). It can be concluded that properly designed domed surfaces can significantly reduce the normal adhesion force when compared to flat surfaces. [ABSTRACT FROM AUTHOR]

Since it is requested that the smashed straw should not be scattered onto the stubble in the first season harvest, a smashing and scattering device matched with the first season harvester of ratoon rice was designed in this paper to smash and scatter the straw into the rolling area. The main structural parameters affecting the straw scattering performance were determined by theoretical analysis of the deflecting performance of the straw deflector. EDEM software was used to simulate and analyze the straw scattering situation under the action of the deflector. Taking the qualified rate of straw scattering as the performance index, the optimal parameter combination of the straw deflector was determined by L27 (313) orthogonal test, and the operating performance of the device was verified by bench test and field comparison test. The test results show that: The optimal parameter combination was 45° between the straw deflector and the vertical direction, 200 mm height difference between straw deflector and outlet, 0° inclination angle of inner deflector and 35° inclination angle of outer deflector. The qualified rate of straw scattering was 72.2% in the corresponding simulation test, 93.6% in the bench test and 95.2% in the field test, which could meet the demand of first season harvest of ratoon rice. [ABSTRACT FROM AUTHOR]

Cinnamoyl isothiocyanate 1 was reacted with 2-cyanoethanoic acid hydrazide 2 to afford 1-cyanoacetyl-4-substituted thiosemicarbazide 3, which on treatment with a mixture of glacial acetic acid and acetic anhydride gave the desired 5-cinnamoylamino-2-cyanomethyl-1,3,4-thiadiazole 4. Compound 4 was subjected to react with aromatic aldehydes, phenylisothiocyanate, carbon disulphide, and arylidene malononitrile to give coumarin 5, thiazolidines 8, 9, and 1,3,4-thiadiazolo[3,2-a]pyridine 13 derivatives. The structures of all synthesized compounds were ascertained by spectral and analytical data. Antimicrobial activity of some of prepared compounds was investigated, and compounds 7, 8 were found to exhibit the highest strength. [ABSTRACT FROM AUTHOR]

We report on the successful use of dexmedetomidine to treat persistent intractable hiccup in a child who underwent cochlear implantation under sevoflurane-fentanyl anesthesia. [ABSTRACT FROM AUTHOR]

• The output impedance model of VSynC-based DFIG is derived and validated first time. • The low-frequency negative impedance characteristic is thoroughly investigated. • The interaction stability between VSynC-based DFIG and power gird is studied. Virtual synchronous control (VSynC) technology that mimics the behavior of a conventional synchronous generator can be applied in wind turbines (WTs), where it can effectively improve equivalent inertia, damping coefficient, and wind power permeability. Given the unique partial-scale converter structure of a doubly-fed induction generator (DFIG) and its complicated DFIG-grid coupling effect, the grid-connected VSynC-based DFIG WTs have gained little attention. Moreover, under a weak grid condition, some unstable modes of VSynC can interact with the wind power system, which impacts the DFIG's dynamic characteristics and system stability. To bridge the gap, this study proposes an output impedance model for a VSynC-based DFIG to analyze the grid-connected stability in weak grids. First, the output impedance mathematical model for a VSynC-based DFIG is derived and explained. On the basis of this novel model, the low-frequency characteristics and vital unstable factors of a VSynC-based DFIG are comprehensively investigated. The impact of different VSynC parameters and grid strengths are extensively studied. Finally, the proposed output impedance model is validated by direct current disturbing theory, frequency scanning method, generalized Nyquist criterion, and time-domain simulation (MATLAB/Simulink). All the obtained results are consistent with each other and prove the effectiveness and accuracy of the proposed impedance model. [ABSTRACT FROM AUTHOR]