Maximum Head Research Articles

Mechanism analysis of the abnormal head-cover vibration of an ultra-high-head pump-turbine operating in pump mode by CFD and FEM

ABSTRACT Hydraulic excitation causes abnormal head-cover vibration in some pump-turbines, particularly as design heads continue to rise. Pump-turbines with heads exceeding 600 m have reported such vibrations in pump mode, and it is urgent to reveal the reasons. A study was conducted on a head-cover of a pump-turbine with a maximum head of 660 m by 3D computational fluid dynamics (CFD) and finite element method (FEM) numerical simulations to investigate the hydraulic excitation source and vibration mechanism. Results show that the intensive vibration is related to the coincidence of frequency and mode between abnormal pressure pulsations with frequency 6–8f n and the low-order wet mode of the head-cover. A new flow pattern termed the rolling vortex was discovered in the vaneless space under high-head pumping conditions. The 6–8f n pressure pulsations result from the interaction between rolling vortices and guide-vanes, similar to the rotor-stator interaction. The flow mechanism of the rolling vortices is that the outflow velocity near the hub at the runner outlet is higher than that near the shroud, due to the positive blade lean angle and the X-shape distorted blades. Suppressing rolling vortices may help eliminate the abnormal head-cover vibration, which will be attempted in further study.

A study on the application of diffuse axonal multi-axis general evaluation for brain injury assessment in small overlap barrier crash test

PurposeHead injury criterion (HIC) companied by a rotation-based metric was widely believed to be helpful for head injury prediction in road traffic accidents. Recently, the Euro-New Car Assessment Program utilized a newly developed metric called diffuse axonal multi-axis general evaluation (DAMAGE) to explain test device for human occupant restraint (THOR) head injury, which demonstrated excellent ability in capturing concussions and diffuse axonal injuries. However, there is still a lack of comprehensive understanding regarding the effectiveness of using DAMAGE for Hybrid Ⅲ 50th percentile male dummy (H50th) head injury assessment. The objective of this study is to determine whether the DAMAGE could capture the risk of H50th brain injury during small overlap barrier tests. MethodsTo achieve this objective, a total of 24 vehicle crash loading curves were collected as input data for the multi-body simulation. Two commercially available mathematical dynamic models, namely H50th and THOR, were utilized to investigate the differences in head injury response. Subsequently, a decision method known as simple additive weighting was employed to establish a comprehensive brain injury metric by incorporating the weighted HIC and either DAMAGE or brain injury criterion. Furthermore, 35 sets of vehicle crash test data were used to analyze these brain injury metrics. ResultsThe rotational displacement of the THOR head is significantly greater than that of the H50th head. The maximum linear and rotational head accelerations experienced by H50th and THOR models were (544.6 ± 341.7) m/s2, (2468.2 ± 1309.4) rad/s2 and (715.2 ± 332.8) m/s2, (3778.7 ± 1660.6) rad/s2, respectively. Under the same loading condition during small overlap barrier (SOB) tests, THOR exhibits a higher risk of head injury compared to the H50th model. It was observed that the overall head injury response during the small overlap left test condition is greater than that during the small overlap right test. Additionally, an equation was formulated to establish the necessary relationship between the DAMAGE values of THOR and H50th. ConclusionIf H50th rather than THOR is employed as an evaluation tool in SOB crash tests, newly designed vehicles are more likely to achieve superior performance scores. According to the current injury curve for DAMAGE and brain injury criterion, it is highly recommended that HIC along with DAMAGE was prioritized for brain injury assessment in SOB tests.

Optimizing Potassium and Iron Levels for Enhanced Sunflower Yield in Peshawar Valley

Sunflower cultivation is integral to meeting the demand for edible oil seeds, necessitating the optimization of plant nutrient application for optimal crop production. A field trial conducted at the Agronomy Research Farm, The University of Agriculture, Peshawar, during the summer of 2022 aimed to assess the impact of varying potassium and iron levels on sunflower yield and yield components. Four levels of potassium (0, 30, 45, and 60 kg ha-1) and four levels of iron (0, 5, 10, 15 kg ha-1) were investigated using a randomized complete block (RCB) design with three replications, maintaining one control plot in each replication. Iron sulfate and Muriate of potash were utilized as sources of iron and potassium, respectively. Results revealed that applying potassium at a rate of 60 kg ha-1 led to maximum head diameter (18.38 cm), thousand-achene weight (47.56 g), biological yield (7476 kg ha-1), and grain yield (2039 kg ha-1) accompanied by taller plants (169.3 cm). Similarly, iron application at a rate of 15 kg ha-1 resulted in increased plant height (159.2 cm), maximum head diameter (18.01 cm), 1000 achene weight (47.8 g), biological yield (7416 kg ha-1), and grain yield (2062 kg ha-1). Notably, the effect of iron on plant height was non-significant. Based on the findings, the application of potassium at 60 kg ha-1 and iron at 15 kg ha-1 is recommended for achieving higher sunflower yields in agro-climatic conditions of Peshawar valley. This study revealed the significance of tailored nutrient management strategies for maximizing sunflower productivity in specific region

Measurement proprieties of the CROM instrument for assessing head posture, neck retraction and protraction

BackgroundThe CROM instrument is widely used clinically and in research to measure neck range of motion. However, its measurement proprieties during the assessment of protraction and retraction movements were not examined so far. ObjectiveTo analyse the intra- and inter-rater reliability, the concurrent validity of the CROM for measuring head posture, retraction and protraction in healthy subjects. MethodsThirty-three asymptomatic subjects were recruited and assigned in a random order to one of two raters. After a 10-min break, they were examined by a second rater (Assessment 1). After a 30-min break, both raters repeated the examination (Assessment 2). The examination consisted of measuring the head posture, maximum head protraction and maximum retraction. Each movement was repeated 3 times and measured simultaneously with the CROM and with a 3D capture system laboratory. ResultsThe intra-rater reliability of the CROM was excellent for both raters for head posture and all head movements (ICC>0.9, 95% CI: 0.82–0.99, p < 0.01). The inter-rater reliability was excellent for head posture (ICC>0.95, 95% CI: 0.92–0.98, p < 0.01) and good-to-excellent for all movements at both time-points (ICC = 0.73–0.98, 95%CI: 0.45–0.99, p < 0.01). The validity analysis showed moderate-to-strong correlation between instruments for the head posture and head movements [(r) = -0.47 to −0.78), 95% CI: 0.99 to −0.24, p < 0.01]. ConclusionThe CROM instrument has good-to-excellent reliability and adequate validity for measuring cervical position and displacement in the sagittal plane.

Analisis variasi pipa penstock terhadap kecepatan inlet turbin pada PLTMH Boonpring menggunakan CFD

The development of renewable energy is a necessity in order to reduce the consumption of fossil energy. One of the alternative technologies to obtain sustainable energy resources is to use a Micro Hydro Power Plant (PLTMH). In order to obtain high-efficiency power, it is necessary to analyze the maximum head and discharge values. In this study, an analysis of variations in the design of the penstock pipe from the forebay was carried out to obtain the highest velocity value for rotating the water turbine. The method used in this research is a simulation using ANSYS Fluent software. Based on the results obtained, the highest velocity values were obtained for penstock numbers 2 and 4. Pipe elevation causes the flow velocity to increase smoothly. The branching at the inlet does not affect the velocity value but increases the possibility of a vortex which is detrimental to the flow leading to the turbine.

A novel CFD-ANN approach for plunger valve optimization: Cost-effective performance enhancement

This paper introduces a novel computational fluid dynamics-artificial neural network (CFD-ANN) approach that has been devised to enhance the efficiency of plunger valves. The primary emphasis of this research is to achieve an optimal equilibrium between hydraulic flow and geometric configuration. This study is a novel contribution to the field as it explores the flow dynamics of plunger valves using Computational Fluid Dynamics (CFD) and proposes a unique methodology by incorporating Machine Learning (ML) for performance forecasting. An artificial neural network (ANN) architecture was developed using a thorough comprehension of flow physics and the impact of geometric parameters acquired through computational fluid dynamics (CFD). Using optimization, the primary aspects of the Artificial Neural Network (ANN), including the learning algorithm and the number of hidden layers, have been modified. This refinement has resulted in the development of an architecture exhibiting a remarkably high R2 value of 0.987. This architectural design was employed to optimize the plunger valve. By utilizing Artificial Neural Networks (ANN), a comprehensive analysis comprising 1000 distinct configurations was effectively performed, resulting in a significant reduction in time expenditure compared to relying on Computational Fluid Dynamics (CFD). The result was a refined arrangement that achieved maximum head loss, subsequently verified using computational fluid dynamics (CFD) simulations, resulting in a minimal discrepancy of 2.66%. The efficacy of artificial neural networks (ANN) becomes apparent due to their notable cost-efficiency, along with their capacity to produce outcomes that are arduous and expensive to get through conventional optimization research utilizing computational fluid dynamics (CFD).

The effect of seed sowing rates on spring durum wheat productivity

The purpose of the current study was to establish the effect of sowing rates of spring durum wheat on its productivity. There has been established that reducing seed sowing rates from 7 to 3 million germinated seeds per 1 ha allows reducing spring durum wheat vegetation period by 6–7 days. There has been identified maximum density of productive stems of the two varieties at a seeding rate of 6 and 7 million germinated seeds per 1 ha. The highest productive tillering capacity for two spring durum wheat varieties was obtained at the variant with a norm of 5 million germinated seeds per 1 ha. Thus, according to the experimental variants, the average plant height of the variety ‘Bezenchukskaya Niva’ was 70.6 cm in the control variant and 81.8 cm at a sowing rate of 5 million germinated seeds per 1 ha. The variety ‘Bezenchukskaya Zolotistaya’ has produced the tallest plants of 79.5 cm, with a seeding rate of 4 million germinated seeds per 1 ha. There has been established that the length of a head also increases with a seeding rate decrease; for example, in the variety ‘Bezenchukskaya Niva’, the maximum indicators of the main head were formed at a seeding rate of 5 million germinated seeds per 1 ha, where the maximum length of the main head was 6.7 cm, the number of grains was 27.5 pieces with a weight of 1.47 g. For the variety ‘Bezenchukskaya Zolotistaya’, the maximum head length was 5.6 cm, and the number of grains was 24 pieces at a rate of 4 million germinated seeds per 1 ha. The fullest grain of the variety ‘Bezenchukskaya Niva’ with 53.4 g of ‘1000-grain weight’ was formed at a seeding rate of 5 million germinated seeds per 1 ha; the variety ‘Bezenchukskaya Zolotistaya’ was 50.4g with a norm of 6 million germinated seeds per 1 ha. The maximum productivity of the variety ‘Bezenchukskaya Niva’ was 3.54 t/ha with a seeding rate of 5 million germinated seeds per 1 ha. The variety ‘Bezenchukskaya Zolotistaya’ formed a yield of 3.23 t/ha with a seeding rate of 6 million germinated seeds per 1 ha.

Comparing the Outcomes of Suture Anchor Repair and Rein-Type Capsular Suture for Triangular Fibrocartilage Complex Foveal Tears With a Minimum 2-Year Follow-Up

Recent biomechanical studies have highlighted the importance of foveal reinsertion when repairing triangular fibrocartilage complex (TFCC) injury with foveal tears. However, clinical studies comparing different repair techniques are scarce. We compared the clinical outcomes of suture anchor repair and rein-type capsular suture in patients with TFCC palmer 1B foveal tears with a minimum of 2-year follow-up. This was a single-surgeon, single-center, retrospective, comparative study. We included patients who underwent TFCC repair surgery due to a foveal tear from December 2013 to October 2018 with a minimum follow-up of 24 months. Postoperative Quick Disabilities of Arm, Shoulder, and Hand (QuickDASH) score, Modified Mayo Wrist Score, visual analogue scale for pain, wrist range of motion, and grip strength were compared. We also measured the maximal ulnar head displacement with dynamic ultrasound to quantify distal radioulnar joint stability. In total, 103 patients were in the suture anchor group (group A) and 84 patients in the rein-type capsular suture group (group B). The mean follow-up time exceeded three years for both groups. There was a minimal difference regarding QuickDASH score, visual analogue scale for pain, and grip strength ratio between the two groups. The rein-type group had significantly better Modified Mayo Wrist Score. The suture anchor group showed better distal radioulnar joint stability with dynamic ultrasound, but was more limited in ulnar deviation. However, these differences are most likely clinically insignificant. Both suture anchor repair and rein-type capsular suture yielded satisfactory results for TFCC 1B foveal tear in a minimum of 2-year follow-up. The functional scores were similar, and no major complications or recurrent instability were noted in either group. Retrospective therapeutic comparative investigation IV.

Visualized-experimental assessment on a two-phase thermosyphon loop downcomer state with wide range of filling ratios

The two-phase thermosyphon loop (TPTL), which has an excellent heat transfer performance with simple, compact structure and pump-free advantages, can effectively solve the heat transfer problem under high heat flux. It is necessary to optimize the TPTL to operate in good conditions, especially the state of the downcomer in which the liquid head is one of the critical parameters to determine the driving force of the circulation. However, in the existing studies, the flow features under high filling ratio and high heat flux were ignored in the downcomer. Since a high filling ratio has been proved to have good performance at high heat flux. Herein, the flow characteristics of the TPTL downcomer were seen and quantified using an experimental visual setup under different filling ratios in this study. Two flow features under high heat flux, for the first time, are reported: 1. two-phase flow in the downcomer at high filling ratios. 2. liquid column height oscillation under a partially liquid-filled state. According to the results, the filling ratio significantly impacts the flow characteristics of the downcomer. The TPTL downcomer state, contrary to the traditional understanding, can be partially filled with liquid but not totally filled with fluid all the time, implying that the driving force may be less than the typical assumption. TPTL with a high filling ratio can also provide a maximum gravity pressure head driving force due to the full downcomer. In addition, the bubble pump, which influences by the heat flux, also accelerates the mass flow in the TPTL. Consequently, TPTLs with a high filling ratio showed a significant thermal performance. A partially filled with the liquid phenomenon is demonstrated in moderate filling ratios, and the height of the liquid column will change as the heat flux increases, which indicates the self-regulation of TPTL. When the filling ratio is low, the liquid column height is greatly influenced by the filling ratio. The high liquid column will also give the TPTL excellent thermal performance. The ideal state of a TPTL downcomer is the downcomer filled with two-phase liquid under a high void fraction, which is realized by a high filling ratio TPTL. This paper sheds some light on the downcomer state of TPTLs to optimize the TPTL thermal performance.

Designing and Manufacturing an Affordable and Easy to Use Visual Bio Feedback Device to Fix Forward Head Posture: A Pilot Study Involving Female Students

Forward Head Posture (FHP) is when the head leans forward due to factors such as heavy backpacks or poor computer ergonomics. FHP can lead to neck strain and discomfort as well as potential long-term issues such as arthritis. Treatment options include specialized exercises, orthopedic devices, manual therapy, physical exercises, and visual feedback techniques, along with guidance from specialists in physical medicine and rehabilitation. In this study, a visual feedback-based approach was used to address FHP in female students. The study spanned ten days and included a visual feedback group and a control group. The results showed significant improvements in maximum head angle deviation in the visual feedback group compared to the control group; however, there was no significant change in the DFA number, indicating stability in policy control by the central nervous system. The study demonstrated that visual feedback sessions led to immediate benefits, with participants progressively acquiring skills involving the maintenance of proper head positioning. The test results indicated that the neck angle decreased to less than 15 degrees, indicating a return to a normal state. The versatility of the developed affordable and easy-to-use device and the potential for using smartphone motion sensors for similar visual feedback systems are discussed in this paper as well. The study suggests the promising potential of visual feedback in healthcare, including remote monitoring and smartphone-based solutions.

Transient coupling modeling and dynamic response analysis of hydraulic turbine governing system and shafting system

To address the challenges posed by the connection of new energy sources to the grid, pumped storage power stations (PSPSs) are required to frequently engage in transient processes to maintain load balancing and regulate grid frequency. It remains difficult, however, to evaluate the transient characteristics of the hydraulic turbine governing system (HTGS) and shafting system because of the lack of suitable models. This study seeks to address this challenge by establishing a transient turbine model based on the surface-cluster method and the shafting system transient coupling model, accounting for hydraulic-mechanical-electrical factors. HTGS and shafting systems' dynamic response characteristics are investigated under two small oscillation processes and eleven closure laws of guide vanes (CLGVs). The findings reveal that the shafting system vibration increases with the load drop during small oscillation processes. Conversely, sudden load increases reduce shafting vibration and the change of vibration is related to the force of the blade. Moreover, the study identifies that under the fast-slow two-phase CLGV, the maximum relative head and rotor radial amplitude increase with decreasing guide vanes (GV) opening of the turning point, while the change in maximum relative speed is opposite. Under the slow-fast two-phase CLGV, the maximum head and speed increase with decreasing GV opening of the turning point, while the maximum radial amplitude of the rotor is the opposite. Finally, under all the three-phase CLGVs, the transient characteristics of the head, speed, and shafting vibration under close-close-close (CCC) CLGV are the best. The innovation of this paper is to provide a method to establish the transient coupling model of HTGS and shafting, and to study the stability and transient response characteristics of HTGU.

Biomechanical comparison of different internal fixation devices for transversely unstable Mason type II radial head fractures.

Background: The integrity of the radial head is critical to maintaining elbow joint stability. For radial head fractures requiring surgical treatment, headless compression cannulated screw fixation is a less invasive scheme that has fewer complications. The aim of this study was to compare the mechanical stability of different fixation devices, including headless compression cannulated screws and mini-T-plates, for the fixation of transversely unstable radial head fractures. Methods: Forty identical synthetic radius bones were used to construct transverse unstable radial head fracture models. Parallel, cross, and tripod headless compression cannulated screw fixation and mini-T plate fixation were applied. The structural stiffness of each group was compared by static shear loading. Afterward, cyclic loading was performed in each of the three directions of the radial head, and the shear stability of each group was compared by calculating the maximum radial head displacement at the end of the cycle. Findings: The mini-T plate group had the lowest structural stiffness (51.8 ± 7.7N/mm) and the highest relative displacement of the radial head after cyclic loading (p < 0.05). The tripod headless compression cannulated screw group had the highest structural stiffness among all screw groups (p < 0.05). However, there was no significant difference in the relative displacement of the radial head between the screw groups after cyclic loading in different directions (p > 0.05). Interpretation: In conclusion, the biomechanical stability of the mini-T plate for fixation of transverse unstable radial head fractures is lower than that of headless compression cannulated screws. Tripod fixation provides more stable fixation than parallel and cross fixation with headless compression cannulated screws for the treatment of transversely unstable radial head fractures.

Effect of Integrated Nutrient Management on Yield Attributes, Yield and Economics of Cabbage var Golden Acre under Medziphema Condition

A field experiment was conducted to investigate the effect of integrated nutrient management on growth, yield and quality of cabbage (Brassica oleracea var. capitata) under foothill of Nagaland during rabi season of 2021-2022 at the Experimental Farm of Horticulture, School of Agricultural Sciences, Nagaland University. During the study, 14 treatments and three replications were assessed in RBD. Results revealed that integration of organic manures in combination with inorganic fertilizers or either alone significantly increased the yield, yield attributes and economics of cabbage over control. Among the various treatments, application of 25% NPK + 75% FYM + Biofertilizers (T8) showed maximum head diameter (13.18 cm), head size (147.11 cm2), gross head weight (1410.00 g), net head weight (694.67 g), head compactness (43.27 cm), yield per plot (11.10 kg) and yield per hectare (256.85 q). The highest net return of Rs 6,53,495/- and the highest cost benefit ratio of 5.58 was obtained from treatment T8 (25% NPK + 75% FYM + Biofertilizers). Thus, T8 can be suggested as an effective INM for getting higher yield and net return of cabbage var Golden Acre under foothill of Nagaland.

Feasibility analysis and nail planning ofS2 iliac crest screw placement in children

To evaluate the feasibility of S2 alar iliac screw insertion in Chinese children using computerized three-dimension reconstruction and simulated screw placement technique, and to optimize the measurement of screw parameters. A total of 83 pelvic CT data of children who underwent pelvic CT scan December 2018 to December 2020 were retrospectively analyzed, excluding fractures, deformities, and tumors. There were 44 boys and 39 girls, with an average age of (10.66±3.52) years, and were divided into 4 groups based on age (group A:5 to 7 years old;group B:8 to 10 years old;group C:11-13 years old;group D:14 to 16 years old). The original CT data obtained were imported into Mimics software, and the bony structure of the pelvis was reconstructed, and the maximum and minimum cranial angles of the screws were simulated in the three-dimensional view with the placement of 6.5 mm diameter S2 alar iliac screws. Subsequently, the coronal angle, sagittal angle, transverse angle, total length of the screw, length of the screw in the sacrum, width of the iliac, and distance of the entry point from the skin were measured in 3-Matic software at the maximum and minimum head tilt angles, respectively. The differences among the screw parameters of S2 alar iliac screws in children of different ages and the differences between gender and side were compared and analyzed. In all 83 children, 6.5 mm diameter S2 iliac screws could be placed. There was no significant difference between the side of each screw placement parameter. The 5 to 7 years old children had a significantly smaller screw coronal angle than other age groups, but in the screw sagittal angle, the difference was more mixed. The 5 to 7 years old children could obtain a larger angle at the maximum head tilt angle of the screw, but at the minimum cranial angle, the larger angle was obtained in the age group of 11 to 13 years old. There were no significant differences among the age groups. The coronal angle and sagittal angle under maximum cephalic angle and minimum cranial angle of 5 to 7 years old male were (40.91±2.91)° and (51.85±3.75)° respectively, which were significantly greater than in female. The coronal angle under minimum cranial angle was significantly greater in girls aged 8-10 years old than in boys. For the remaining screw placement angle parameters, there were no significant differences between gender. The differences in the minimum iliac width, the screw length, and the length of the sacral screws showed an increasing trend with age in all age groups. The distance from the screw entry point to the skin in boys were significantly smaller than that of girls. The minimum width of the iliac in boys at 14 to 16 years of age were significantly wider than that in girls at the same stage. In contrast, in girls aged 5 to 7 years and 11 to 13 years, the screw length was significantly longer than that of boys at the same stage. The pelvis of children aged 5 to 16 years can safely accommodate the placement of 6.5 mm diameter S2 alar iliac screws, but the bony structures of the pelvis are developing and growing in children, precise assessment is needed to plan a reasonable screw trajectory and select the appropriate screw length.

Numerical Simulation and Analysis of Hydraulic Turbines Based on BIM for Sustainable Development

Hydropower is considered to be an important way to achieve the sustainable development goal of human progress. The performance of turbines is very important to the safety and stability of hydropower stations. Most of the hydraulic turbine performance studies only use Computational Fluid Dynamics (CFD) for performance simulation, lacking the integration of Building Information Modeling (BIM) technology and CFD. Therefore, a performance analysis model of a Francis turbine based on BIM was put forward in this paper. The BIM software OpenBuildings Designer CONNECT Edition Update 10 was used to build the hydraulic turbine model, and then the BIM model was transferred to the CFD numerical simulation platform ANSYS through the intermediate format conversion. In the ANSYS environment, the numerical simulation of different working conditions was carried out with the help of Fluent 2021 R1 software. The numerical simulation results show that the fluid velocity gradient in the volute was 2~3 m/s under the three working conditions, which was relatively stable. The water flow could progress the guide vane mechanism at a higher speed, and the drainage effect of the volute was better. There were some negative pressure areas at the back of the runner blades and the inlet of draft tube, and the negative pressure value was as high as −420,000 Pa and −436,842 Pa under maximum head conditions, which were prone to cavitation erosion. It is proven that BIM supported the hydraulic turbine performance analysis and provided a geometric information model for hydraulic turbine CFD numerical simulation, meaning that the performance analysis model based on BIM is feasible. This study can expand the application value of BIM and provide guidance for the study of hydraulic turbine numerical simulation using BIM technology in combination with CFD methods.

Larval instar estimation and ultra‐structural analysis of Aphaenogaster cristata (Forel, 1902) and Aphaenogaster pachei (Forel, 1906) (Hymenoptera: Formicidae) from the Himalayas

AbstractThe ontogeny of an organism provides fundamental insights into its life history and evolutionary background. Among insects, especially ants, relatively few observations have been formalized about the morphology of immature stages. Using light and scanning electron microscopy, this study presents the first description of the different larval instars of Aphaenogaster cristata (Forel, 1902) and Aphaenogaster pachei (Forel, 1906), species endemic to the Himalayas that predominate in areas where cold temperature stress and disturbances limit the presence of other ants. The existence of four larval instars was estimated based on the frequency distribution of their measured maximum head widths. We observed discrete alterations in the body constitution and parts among the different instars, suggesting they must follow similar habits until pupation. The two species, however, present noticeable particularities in their mandibles and hair types, suggesting intrinsic life adaptations. Observed traits complementary with previous descriptions with larvae of the genus and related taxa are suggestive of considerable evolutionary distance from Messor, considered the sister clade, which merits further taxonomic investigation in future studies.

Anthropometric Study of the Cephalic Index of Anambra State Students in Madonna University Nigeria

Background: Cephalometry is a subfield of anthropometry that involves the estimation of the cephalic index. The cephalic index is a significant metric used to ascertain the race and sex of an unidentified individual. Materials and Methods: This study was descriptive and cross-sectional and was conducted on Anambra State students at Madonna University. Elele campus, Rivers State, aged 16–24 years. The cephalic index was determined by applying the following formula: the maximum breadth of the head divided by the maximum length of the head, multiplied by 100. Hundred subjects, comprising 150 males and 150 females from Anambra State at Madonna University, were measured. Anthropometrical parameters measured were maximum head breadth and maximum head length. Results and Discussion: The analysis shows that there is no significant difference in the age groups with the cephalic indices of males and females. The prevalence of hyperbrachycephaly is significantly higher in males and females, while dolicocephaly is observed infrequently. Conclusion: This study shows that the males and females showed no differences on the basis of the cephalic index. It also reveals that the students in this study share similarities with Urhobo males and females based on their head types. The findings of this study will hold significant implications for the fields of forensics, medicine, and biometrics.

Rancang Bangun Pompa Air Aliran Aksial Pipa Pvc 5 Inci Berpenggerak Motor Listrik

&lt;p&gt;&lt;em&gt;Axial pumps are one type of pump that is widely used for industrial purposes to move fluids from low places to higher places with large capacities. The axial pump has very complicated components so it has a very expensive price. This study aims to design and build an axial flow pump with a 5-inch PVC pipe casing driven by an electric motor. The design process begins with the determination of pump specifications including the capacity of the fluid you want to flow and the height of the fluid you want to move, then proceed with calculations including the capacity of the electric motor, shaft, and bearings, then proceed with the process of making components according to the calculations that have been done and the final stage is the process assembly and testing. The result of the calculation is that for an axial pump specification with a maximum head of 0.5 m, a pipe diameter of 0.14 m, and a maximum capacity of fluid that can flow 0.02 m3/s, a ½ Hp motor is required with a drive shaft diameter of 10 mm. The test results show that the pump can operate properly, the water capacity that can be moved is 0.0138 m3/s for the variation in the number of blades 2 and 0.0161 m3/s for the variation in the number of blades 3. So the efficiency for the variation in the number of blades 2 is 46.54% and for blade 3 is 54.53%&lt;/em&gt;&lt;/p&gt;

Operating room black box: Scrutinizer of theatre practices

ObjectiveAdverse surgical events are a major cause of morbidity, mortality, and disability worldwide. The cause of many such events can be attributed to interruptions in the operating room (OR), multitasking by surgeons, etc. The objective of this study was to observe the types and frequency of intraoperative workflow interruptions in our ORs. MethodThis cross-sectional study was conducted from March to April of 2023. An observational approach using an audio-video recording device was employed to record OR flow disruptions. One elective OR and one emergency OR under the Department of General Surgery were selected for the study. All open and laparoscopic surgeries conducted in the selected ORs were included. An Internet Protocol camera was installed in the selected ORs with a view of the entire room, including the anesthesia station. Audio-video recording was started after the first incision and stopped after closure of the surgical site. ResultOf the 51 cases that were studied, 45 (88.2%) were elective, and 18 (35.3%) were laparoscopic cases. They could be classified into 8 types of open procedures and 4 types of laparoscopic procedures. The mean maximum headcount inside the OR was 15.5 ± 3.6 and doors opened on average of 15.8 ± 6.0 times during a procedure. Other interruptions were surgeons attending phone calls (24, 47.1%), leaving the sterile area (21, 41.2%), technical disturbances (32, 62.7%), anesthetic interruptions (18, 35.3%), and faulty instruments (29, 56.9%). Elective procedures had a significantly higher average number of interruptions per operating hour than emergency procedures (17.5 ± 8.6 vs. 7.1 ± 2.9, p < 0.01). ConclusionPreventable factors such as faulty instruments, anesthetic interruption, and attending phone calls by the surgeon are commonly observed in ORs. They need to be addressed by timely surgical audits or the adoption of continued surveillance methods that can help take measures to minimize their occurrence.

Experimental comparison of the upstream head using the non-rotating model of the vertical ultra-low head hydro turbine with its prototype

A vertical ultra-low head (VULH) turbine is a pico-scale hydro turbine applicable to open canal flow with or without head drop. This conceptualized turbine rotates at a lower speed. In the case of water flow on a canal without head drop condition, the prediction of the upstream head is challenging due to the change in the direction of the water flow path on this conceptualized system. Assuming the head at the primary level of design, an experimental study has been conducted to judge the upstream head of water flow using the two-dimensional non-rotating model (NRM) before the use of a prototype of the turbine. The runner was designed with a conventional method whereas the design of NRM was based on the diameters of the runner designed and the orifice openings on it. The experiments were conducted on a newly developed VULH Turbine test rig of size 10 m x 1.5 m x 2 m with a maximum flow rate capacity of 120 LPS and a maximum upstream head of 0.75 m. The tests were completed for upstream head variation using three different sets of NRM having an orifice cut angle of 15°, 18°, and 22.5° and a prototype of the runner at a constant speed for different flow rates. From the comparisons made, the closest NRM was selected that showed a similar upstream head at the maximum efficiency point of the runner. The research concluded with the finding that the NRM can be used to predict the upstream head of the VULH turbine instead of the rotating model.