Predominant Mode Research Articles

Experimental Investigation of Ultrasonic Vibration-Assisted Grinding of HVOF-Sprayed WC-10Co-4Cr Coating

WC-10Co-4Cr coating is highly valued for its corrosion resistance and wear resistance when applied using the high-velocity oxy-fuel (HVOF) spraying method. However, conventional grinding (CG) of this coating presents challenges, including substantial grinding forces and elevated surface temperatures. To address these concerns, our study proposed the utilization of ultrasonic vibration-assisted grinding (UVAG) as a means to enhance the machining properties of HVOF-sprayed WC-10Co-4Cr coatings. Comparative experiments were conducted to analyze the impacts of various factors on the grinding forces and surface roughness in UVAG and CG processes. Additionally, the topography of the ground surfaces was examined to gain insights into the material removal mechanism in UVAG. The experimental outcomes reveal significant reductions in tangential and normal grinding forces, amounting to 15.47% and 22.23%, respectively, in UVAG when compared with CG. Furthermore, UVAG led to a roughly 29.14% decrease in ground surface roughness compared with CG. Microscopic analysis of the ground surfaces using scanning electron microscopy (SEM) indicated that ductile removal was the predominant material removal mode in UVAG. Overall, UVAG was found to be effective in diminishing grinding forces, improving ground surface roughness, and enhancing surface integrity when contrasted with CG. These findings introduce a novel approach for processing WC-10Co-4Cr coatings.

Effects of moisture content and fibrous structure on the uniaxial compression behavior of natural bamboo

The compression properties of natural bamboo were tested, and the crush morphologies with different moisture contents and fibrous structure were observed. Real-time acoustic emission (AE) and optical microscope videos captured the compression behaviors. Dry bamboo internodes showcased 100% higher compression strength with shearing as the predominant failure mode, while the wet samples demonstrated delamination and splitting. AE and fracture morphology indicated five compression behavior categories. Bamboo node samples exhibited heightened compressive strength and modulus than internodes due to their coarser 3D fibrous structures. This investigation offers valuable insights for the development of engineering bamboo materials.

Transcriptome analysis of ovarian tissues highlights genes controlling energy homeostasis and oxidative stress as potential drivers of heterosis for egg number and clutch size in crossbred laying hens

Heterosis is the major benefit of crossbreeding and has been exploited in laying hens breeding for a long time. This genetic phenomenon has been linked to various modes of nonadditive gene action. However, the molecular mechanism of heterosis for egg production in laying hens has not been fully elucidated. To fill this research gap, we sequenced mRNAs and lncRNAs of the ovary stroma containing prehierarchical follicles in White Leghorn, Rhode Island Red chickens as well as their reciprocal crossbreds that demonstrated heterosis for egg number and clutch size. We further delineated the modes of mRNAs and lncRNAs expression to identify their potential functions in the observed heterosis. Results showed that dominance was the principal mode of nonadditive expression exhibited by mRNAs and lncRNAs in the prehierarchical follicles of crossbred hens. Specifically, low-parent dominance was the main mode of mRNA expression, while high-parent dominance was the predominant mode of lncRNA expression. Important pathways enriched by genes that showed higher expression in crossbreds compared to either one or both parental lines were cell adhesion molecules, tyrosine and purine metabolism. In contrast, ECM-receptor interaction, focal adhesion, PPAR signaling, and ferroptosis were enriched in genes with lower expression in the crossbred. Protein network interaction identified nonadditively expressed genes including apolipoprotein B (APOB), transferrin, acyl-CoA synthetase medium-chain family member (APOBEC) 3, APOBEC1 complementation factor, and cathepsin S as hub genes. Among these potential hub genes, APOB was the only gene with underdominance expression common to the 2 reciprocal crossbred lines, and has been linked to oxidative stress. LncRNAs with nonadditive expression in the crossbred hens targeted natriuretic peptide receptor 1, epidermal differentiation protein beta, spermatogenesis-associated gene 22, sperm-associated antigen 16, melanocortin 2 receptor, dolichol kinase, glycine amiinotransferase, and prolactin releasing hormone receptor. In conclusion, genes with nonadditive expression in the crossbred may play crucial roles in follicle growth and atresia by improving follicle competence and increasing oxidative stress, respectively. These 2 phenomena could underpin heterosis for egg production in crossbred laying hens.

Foreign Trade of the State of Acre, Brazil, Between 2019 and 2022: An Analysis of Commercial Interactions

Purpose: The objective of this study was to analyze import and export operations in the state of Acre between 2019 and 2022, aiming to understand the importance of local foreign trade and its recent advancements. Theoretical framework: The continuous evolution of trade interactions between nations is crucial for economic development, regardless of a country's economic stage, and foreign trade emerges as a fundamental pillar for this growth. However, despite Brazil being one of the largest global economies, its exports still do not reach their full potential, highlighting the importance of studying foreign trade, especially in the context of the state of Acre, due to its strategic location and potential in the Amazon Region. Methodology: This study adopts a descriptive approach and quantitative methodology to meticulously analyze import and export operations in the period from 2019 to 2022, using official data from the Ministry of Development, Industry, Trade, and Services (MDIC), available on the Comex Stat electronic platform. Findings: The analysis recorded a notable increase in exports, mainly to Peru, the United States, and Hong Kong, driven by the growth of exports of wood, nuts, corn, and soybeans, while imports also grew, with China being the main source of imported products. Maritime transport emerged as the predominant mode for both exports and imports, highlighting the importance of the Pacific Highway for the state's commercial transactions. Research, practical & social implications: Future research should investigate how the understanding of the presented data can influence the planning for sustainable economic growth in Acre, as well as its global integration in trade, considering relations with strategically neighboring countries. Originality/value: The results indicate that Acre is strategically expanding its trade based on diversification, integration with key partners, and logistical adaptation, positioning itself for a relevant role in the global scenario and contributing to the development of the Amazon Region.

Strengthening phase and mechanical property analysis of artificially aged Al7075 – Ni coated Al2024 composites

This technical paper demonstrates the possibilities of nickel (Ni) coated Al2024 powder reinforcement in an Al7075 matrix using the liquid stir casting technique. Additionally, the paper focuses on achieving stable properties by implementing artificial aging heat treatment. To apply the Ni coating, the electroless nickel plating technique was utilized, and a minimum coating thickness of 8 μm was determined to effectively prevent the dissolution of Al2024 powder reinforcements within the Al7075 matrix. Stir casting facilitated the uniform dispersion of the coated Al2024 powder up to a weight percentage of 7%. Subsequently, the Al7075 alloy and composites underwent artificial aging through solution heat treatment (SHT) at 450 °C for 4 h, followed by water quenching and aging at temperatures of 120, 150, and 180 °C. Aging at 120 °C was found to yield superior results compared to aging at 150 and 180 °C, thus identified as the optimum aging temperature. When the Ni coating thickness was increased beyond the optimal 8 μm, the resulting enhancements in hardness for both as-cast and peak-aged specimens, as well as the tensile strength, were not significant. The improvements observed were only marginal, ranging between 2 to 3%. Fracture surface analysis revealed that the predominant fracture mode in the Al7075 alloy was ductile, characterized by dimple rupture. In the as-cast Al7075-(7%, 8 μm) Al2024 composite, a mixed fracture mode comprising both brittle and ductile characteristics was observed. In the peak-aged (120 °C) Al7075-(7%, 8 μm)Al2024 composite, the overall fracture mode exhibited a dominant brittle nature. Analytical techniques including XRD, TEM, and EDS confirmed the presence of Mg2Si, MgZn2, CuAl2, and CuAl2Mg phases in the peak-aged (120 °C) Al7075-(7%, 8 μm) Al2024 composite. These phases contributed to the enhancement of the properties of both the Al7075 alloy and its composites. The developed composites can be used in automobile parts and aerospace applications.

Narrowband underwater vector sensor using michroelectromechanical systems

A narrowband underwater vector sensor using microelectromechanical (MEMS) systems is demonstrated. A combination of two pressure gradient MEMS sensors and an omnidirectional hydrophone allows for determination of the direction of arrival (DOA) of income sound over 360 degrees azimuth. The MEMS sensors, inspired on the hearing system of the Ormia-ochracea fly, consist of two wings connected by a bridge and anchored to the substrate by a tortional bean. They are operated with open back to allow a cosine dependence with the angle of incidence in the predominant bending vibrational mode. In the vector sensor, two MEMS sensors are orthogonally arranged to provide a cosine and sine directional pattern. When combined with an omnidirectional hydrophone that shares the same phase center, an arctangent estimator is used for DOA determination. The MEMS sensors are operated near resonance to filter out noise coming from undesired bands and improve the signal-to-noise ratio. A correction algorithm is applied to compensate frequency response differences. Two configurations have been demonstrated with the MEMS sensors enclosed in silicone oil and in air. The standard deviation of the measured DOA error has been computed for both configurations to be less than 5 degrees for various types of sound stimuli.

COMPARISON OF SHEAR BOND STRENGTH OF THREE COMPOSITE RESIN REPAIR MATERIAL WITH CERAMIC AND COBALT CHROMIUM SURFACES AFTER VARIOUS SURFACE TREATMENTS - AN INVITRO STUDY

Aim:The objective of this study was to evaluate the shear bond strength of composite resin repair material with ceramic and cobalt chromium surfaces after various surface treatments and the mode of bond failures by stereo microscope. Materials An Methods: Thirty Ceramic and thirty Cobalt chromium samples (10x10x2mm) were prepared .The samples were divided into three groups for ceramic -CI,CII,CIII and for metal -M1,MII and MIII .Three composite resin repair materials were used (1) Restorative composite (control)- [C Group ] ,(2)SHOFU P & R Ceramic repair kit-[S Group] (3) Ivoclar Ceramic Repair System intro pack after surface modification withintraoral sandblaster – [I Group].The composite material was added 6x4mm using a metal holder .All specimens were subjected to a standard shear load in the universal testing machine until fracture occurred. All debonded samples were examined under stereomicroscope to determine the type of failure .The data was analyzed using one-way ANOVA test of variance and Post hoc comparison was applied at 95 % confidence level. Results: Igroup showed the highest shear bond strength followed by S group in ceramic and metal samples. The C group showed least shear bond strength. The predominant mode of failure among the C group in ceramic and Co Cr metal samples was adhesive failure , S Group showed 50% adhesive and 50% mixed type of failure in ceramic samples (CII) in cobalt chromium samples(MII),it showed 70 % adhesive and 30% mixed failure . I group showed 100% mixed failure in ceramic samples(CIII) group ,and 80% mixed and 20% adhesive failure in cobalt chromium samples(MIII). Conclusion:The surface modified with intra oral sandblaster and repaired with Ivoclar ceramic repair kit showed the most favorable results in ceramic and cobalt chromium samples.

Epidemiology and clinical characteristics of trauma in older patients transferred from long-term care hospitals to emergency departments: A nationwide retrospective study in South Korea

BackgroundSouth Korea's aging population had leg to an increased number of long-term care hospitals (LTCHs), and increased transfer of older patients to emergency departments (EDs). This study investigated the epidemiological and injury profiles of LTCH patients aged ≥65 who were transferred from LTCHs to EDs due to trauma. Method: This retrospective study conducted between January 2014 and December 2019 in South Korea utilized data from the National Emergency Department Information System. The requirement for informed consent was waived by the IRB due to the retrospective nature of the study. Patient information was anonymized prior to analysis. ResultsOf the 1,472,006 trauma cases aged ≥65, 14,469 came from LTCHs. Outcomes varied: 44.1% were discharged, 40.6% were admitted to general wards (GW), 5.9% to intensive care units (ICU), 2.4% to other hospitals, and 6.5% returned to LTCHs. ED length of stay (LOS) was longest in the death (410.28 ± 559.73 min) and GW admission (390.12 ± 621.71 min) groups. Falls were the main cause of injury (50.1%), and the most common fracture was femoral (71.6%). Femoral and shoulder/upper extremity fractures increased hospitalization risk only, whereas self-harm increased both hospitalization and mortality risk. ConclusionVisits to the ED by older patients from LTCH for trauma were avoidable in 50.6% of cases. Additionally, these patients had longer ED LOS and higher hospitalization rates than non-LTCH patients. Falls were the predominant mode of presentation, femoral fracture was the most common fracture among patients from LTCH.

The mechanism for Li-addition induced homogeneous deformation in Mg-4.5wt.% Li alloy

The mechanism by which Li additions induce a more homogeneous deformation was systematically investigated in this study by comparing the deformation behavior of pure Mg and Mg-4.5 wt.% Li using experiments, crystal plasticity simulations, and theoretical calculations. The results of the digital image correlation measurements showed that under tension along the transverse direction (TD), strong localized deformation bands with an angle of approximately 20° with respect to the TD were observed in pure Mg, but were absent in Mg-4.5 wt.% Li. Slip trace analyses indicated that basal slip was the predominant deformation mode for pure Mg, whereas that for Mg-4.5 wt.% Li was prismatic slip. A high relative activity of pyramidal 〈c+a〉 slip, approximately 17 %, was observed in Mg-4.5 wt.% Li at a high strain of 10 %. Contraction or double twins were hardly detected during the entire tension process. Crystal plasticity simulations revealed that the 4.5 wt.% Li addition dramatically reduced the critical resolved shear stress (CRSS) ratio of pyramidal 〈c+a〉 slip: prismatic slip: basal slip, which was 31.5:21:1 for pure Mg and 4.3:1.3:1 for Mg-4.5 wt.% Li. Theoretical calculations using the CRSS ratios determined by simulations revealed that easy and uniform deformation propagation induced by a dramatically reduced CRSS ratio of prismatic slip to basal slip played a more important role in improving the deformation homogeneity, in addition to the enhanced activity of pyramidal 〈c+a〉 slip. The mechanisms for how Li additions improve the ductility of Mg are also revisited in this paper.

Exploring Gender Multiplicity through the Lens of Post- Lacanian Psychoanalysis

Sexual difference must be recognized in thought and human interactions to enable people to find their real source of jouissance. The Lacanian finding of ‘masculine phallic desire’ and ‘feminine libidinal desire’ in all human beings, irrespective of their biological sex-gender, paved the way for rethinking gender identities. It calls for reforming inter-human relations from the presently predominant utilitarian mode to the one based on love and recognition of the other. Gender is an arbitrary construct to serve the interests of males in finding phallic sexual pleasure, power and recognition in their social life. Assertion of sexual difference and gender multiplicity will enable human beings to find the other human being as their actual desired object, beyond the pleasures offered by wealth, comforts and commodities.

Monkeypox virus infection: A clinical review based on the 2022 global outbreak

Monkeypox (mpox) is a zoonotic infection caused by an orthopox DNA virus of the family which causes smallpox. The new outbreak of mpox was first reported in Europe in May 2022, which led to cases being reported in non-endemic countries across the globe. The main modes of human-to-human transmission are through bodily secretions or contact with skin sores. More than 83,000 cases of mpox have been reported globally in 110 affected countries, with 72 confirmed deaths. The predominant mode of transmission is through animal-to-human infected body fluids. The main clinical presentation of patients with mpox is with mucocutaneous manifestation with a range of recorded descriptions of the skin lesions. Most of the patients recover without any medical intervention as mostly the disease is self-limiting. The usual supportive care is needed. Although there is no specific treatment, yet antivirals are used for the treatment of mpox which were originally developed for use in patients with smallpox. At present, there are two available vaccines which can mitigate the risk of developing mpox. The timely global collaboration between the World Health Organization and different countries has helped to mitigate the public health impact of mpox.

Understanding the Mode and Factors Influencing Cut-Throat Injuries in a Tribal-Dominated Population in Eastern India.

Introduction Traditionally, injuries have often been perceived as random and inevitable 'accidents'.However, in the current context, both intentional and unintentional injuries are preventable. Among these, neck injuries can be particularly complex, encompassing homicidal, suicidal, or accidental causes. Despite extensive research on the different modes and patterns of cut-throat injuries in the general population, this study aims to look deeper into this phenomenon within a unique context. Our investigation is centered in the Eastern part of India, among a tribal-dominated populationwho live with their traditional culture. Method In this prospective observational study, 50 cut-throat patients were included, who reported to the emergency department and then were referred to the ENT department. Parameters such as age, sex, anatomical location, mode of cut-throat injury, prior substance abuse, psychiatric issues, socioeconomic level, and length of hospital stay were considered for analysis. Results The majority (n=40, 80%) of patients belonged to tribal communitiesand most were young adults. Cut-throat injuries were predominantly caused by suicide (n=36, 72%) and homicide (n=12, 24%). Among tribals, 85% (n=34) of the cases were suicidal. Among suicidal cases, 86.11% (n=31) had a history of substance abusewhile 22.22% (n=8) had a history of psychiatric illnesses. Conclusion In Eastern India, among the tribal-dominated population, suicide emerges as the predominant mode of cut-throat injuries, which is notably distinct from patterns observed in the general population of developing countries. These were often associated with substance abuse.Future interventions and public health efforts in these regions should consider these factors in the development of targeted strategies aimed at prevention and support for at-risk individuals.

Retention and transport of PFOA and its fluorinated substitute, GenX, through water-saturated soil columns

Perfluoro-2-propoxypropanoic acid (GenX) has emerged as a substitute for perfluorooctanoic acid (PFOA) especially since PFOA was listed among the persistent organic pollutants (POPs) by the Stockholm Convention in 2019. However, limited knowledge exists regarding the behavior and mobility of GenX in natural soils hindering the prediction of its environmental fate. This study investigated the mobility and retention of GenX and PFOA in soils under batch and water-saturated flow-through conditions. Batch experiments revealed that GenX has a lower binding affinity to soil than longer-chained PFOA, potentially threatening groundwater resources. Unlike metal-oxides/minerals (ferrihydrite, gibbsite and manganese dioxide), biochar (BC) and activated carbon (AC) amendments significantly enhanced the sorption of both GenX and PFOA in soil. Sorption data on minerals and carbonaceous materials implied that for shorter-chained GenX, the predominant mode of sorption was through electrostatic (ionic) interactions, while for longer-chained PFOA, hydrophobic interactions became progressively more important with increasing chain length. The dynamic flow experiments demonstrated that these soil amendments enhanced the retention of both compounds, thereby decreasing their mobility. Simultaneous injection of both compounds into columns pre-loaded with either PFOA or GenX increased their retardation. GenX sorption was more affected by pre-sorbed PFOA compared to the minimal impact of pre-loaded GenX on PFOA sorption. A newly developed reactive transport model, which incorporates a two-site sorption model and accounts for kinetic-limited processes, accurately predicted the sorption and transport of both compounds in single and binary contamination systems. These findings have important implications for predicting and assessing the fate and mobility of per- and polyfluoroalkyl substances (PFAS) in soils and groundwaters.

A Brief Analysis of the Legal Status of Electronic Agents in Commercial Transactions

With the continuous advancement of technology, online transactions have gradually become the predominant mode of commerce in society. Currently, a new type of transaction facilitator has emerged in online transactions, known as electronic agents. This specialized concept and its legal definition originated in Western countries, and China has also adopted this concept. Electronic agents cannot be construed as natural persons, nor can they be fashioned as legal entities. They are merely tools capable of executing the will of individuals, albeit with some distinctions from conventional transaction tools. Establishing the legal status of electronic agents can reduce conflicts and contradictions related to online transactions in our current lives, facilitate the development of automated electronic transactions, and promote the rapid progress of our society. Currently, legislation in China in this regard remains uncharted territory, yet our lives are already enveloped by these online transactions. This has resulted in the inability to reach a unanimous resolution for many disputes involving electronic agents in our daily lives, leaving judges to resolve issues based on fundamental legislative principles or relevant legal provisions. The party employing the machine is often an organization with superior cognitive abilities compared to individuals. Therefore, we should consider electronic agents as their employees, and the actions they take should be the responsibility of legal or non-legal entities. It is essential to prioritize the protection of the weaker party as much as possible.

Long-term Outcomes of Polytetrafluoroethylene Bicuspid Pulmonary Valve Replacement

BackgroundIn 2016 we reported promising midterm outcomes of bicuspid pulmonary valve replacement using 0.1-mm polytetrafluoroethylene (PTFE) membrane. This follow-up study analyzes long-term outcomes and risk factors for reintervention and structural valve deterioration (SVD). MethodsWe performed a retrospective review of the original 119 patients who underwent PTFE bicuspid pulmonary valve replacement. Median patient age was 16.9 years (range, 0.4-57.1). Reintervention was defined as any surgical or percutaneous catheter procedure on the PTFE valve. SVD was defined as development of a peak pressure gradient ≥ 50 mm Hg or at least a moderate amount of pulmonary regurgitation on follow-up echocardiography. ResultsThe median follow-up duration was 9.5 years. The survival rate was 96.5% at 5 and 10 years, with 2 early and 2 late mortalities. Freedom from reintervention was 90.0% at 5 years and 63.3% at 10 years. Freedom from SVD was 92.8% at 5 years and 51.1% at 10 years, with regurgitation the predominant mode (64.6%). Freedom from both reintervention and SVD at 5 and 10 years were 89.1% and 49.5%, respectively. Multivariable analysis identified smaller valve diameter (hazard ratio, 0.82; P < .001) and more than trivial pulmonary regurgitation at discharge (hazard ratio, 5.81; P < .001) as risk factors for reintervention or SVD. ConclusionsLong-term results of the PTFE bicuspid pulmonary valve replacement were acceptable. However, improvements may be needed to reduce technical error and improve durability. Smaller valve diameter and more than trivial pulmonary regurgitation at discharge were risk factors for reintervention or SVD, warranting careful follow-up for timely reintervention.

Structural performance of friction-grip bolted shear connectors in cold-formed steel composite beams

Nowadays, composite beams consisting of steel beams and concrete slabs are widely used in the construction industry. In this research, an experimental study was carried out to investigate the performance of friction-grip bolted shear connectors in composite beams with cold-formed steel sections. For this purpose, 17 full-scale push-out tests were examined according to EC4 in order to investigate the performance of this connection. Of particular interests were load-slip curves, the maximum shear capacity, ultimate slip (ductility) and failure modes. Experimental results show that the behavior of this connection is different from that of headed-stud shear connector. The diameter and strength of bolt and thickness of cold-formed steel section have the most critical effects on the shear capacity and ductility of these connections. Furthermore, 3D finite element modeling was performed and validated against experimental results. The results reveals that numerical models can estimate the capacity of friction-grip bolted shear connectors with acceptable accuracy. The results also highlight that the predominant failure mode in all specimens is bearing. Thus, the use of AISI equations to determine the bearing capacity of the screw holes as the shear capacity of friction-grip bolted shear connectors is recommended. It is also concluded that this connection possesses the necessary ductility according to the EC4 (= 6 mm) and is suitable for use in composite beams with cold-formed steel sections.

Biomechanical Comparison of 3 Adjustable-Loop Suspensory Devices for All-Inside ACL Reconstruction: A Time-Zero Full-Construct Model.

Little is known about the stability of adjustable-loop devices (ALDs) for anterior cruciate ligament (ACL) reconstruction (ACLR). To evaluate the stabilization behavior of 3 different types of ALDs for all-inside ACLR in a full-construct surgical technique-based manner. Controlled laboratory study. The femoral and tibial devices of Ultrabutton (Smith & Nephew), Infinity (Conmed), and TightRope II (Arthrex) were applied to quadrupled bovine tendon grafts (n = 8 each) with tibial-sided traction applied (350 N) for graft tensioning in a simulated fully extended knee. Knotless femoral graft fixation was based on either a suture-locking device (SLD; Ultrabutton), button-locking device (BLD; Infinity), or dual-locking device (DLD; TightRope II). All constructs were progressively loaded (50 N/500 cycles) from 50 to 300 N for 3000 cycles (0.75 Hz), including complete unloading situations and pull to failure (50 mm/min). Construct elongation, stiffness, and ultimate load were analyzed. BLD showed significantly greater initial elongation (-2.69 ± 0.15 mm) than DLD (-3.19 ± 0.21 mm; P < .001) but behaved similarly to SLD (-2.93 ± 0.23 mm). While DLD and SLD had the smallest initial elongation at the same significance level, they behaved opposite to each other with gradually increasing peak loading. At the end of testing, DLD had the lowest (-0.64 ± 0.32 mm) and SLD the highest (3.41 ± 1.01 mm) total elongation (P < .003 for both). SLD displayed significantly higher dynamic elongation (6.34 ± 0.23 mm) than BLD (3.21 ± 0.61 mm) and DLD (2.56 ± 0.31 mm) (P < .001 for both). The failure load of BLD (865.0 ± 183.8 N) was significantly lower (P < .026) compared with SLD and DLD (>1000 N). The predominant failure mode was suture rupture and tibial bone breakage with button subsidence (SLD, n = 4). No significant difference in stiffness between constructs was found. While DLD successfully restricted critical construct elongation, BLD partially and SLD completely exceeded the clinical failure threshold (>3 mm) of plastic elongation with loop lengthening during increasing cyclic peak loading with complete unloading. Higher failure loads of SLD and DLD implants (>1000 N) were achieved at similar construct stiffness to BLD. A detailed biomechanical understanding of the stabilization potential is pertinent to the continued evolution of ALDs to improve clinical outcomes.

Analysis and approach to renal trauma: A five-year experience at a level I trauma centre in north India

PurposeRenal trauma constitutes 0.5% – 5% of all trauma patients, and 10% – 20% of abdominal trauma. It is the most commonly injured organ in the genitourinary tract. Road traffic crash (RTC) is the most common cause. In recent years due to the advances in radiological imaging and endovascular techniques, there has been an increase in the nonoperative management of renal trauma. We investigated a large trauma cohort at a level I trauma centre to evaluate patients' demographics with renal trauma, their management, and the outcomes. MethodsThis was a retrospective analysis of the prospectively collected data of renal trauma patients managed from January 2016 to December 2020. Patients who visited the level I trauma centre in north India with renal trauma were included in this study. Patients who were dead on arrival in the emergency department were excluded. Demographics, mechanism of injury, presence of hemorrhagic shock, associated injuries, complications, length of hospital stay (LOS), discharge, and mortality were recorded. The data were entered in Microsoft Excel 365 and analysed using SPSS version 21. ResultsThis study collected data from 303 renal trauma patients. Males constituted 86.5% of the patients. Most patients were young, aged from 20 – 40 years. Blunt renal trauma was the predominant mode of injury (n = 270, 89.1%). RTCs (n = 190, 62.7%) and falls from height (n = 65, 21.4%) were the 2 most common mechanisms of injury. Focused assessment with sonography in trauma was positive in 68.4% of patients. Grade III (grading by the American Association for the Surgery of Trauma) renal trauma (30.4%) was the most common grade in our study. The liver (n = 104, 34.3%) and splenic trauma (n = 96, 31.7%) were the most commonly associated injuries. Of the 303 patients, 260 (85.8%) were managed nonoperatively. The mean (SD) of the patients’ LOS was 12.5 (6.5) days. There were 25 (8.3%) mortalities during the study period and all of them had associated other injuries. The comparison of LOS of isolated renal trauma group and renal trauma with associated injuries group was not statistically significant (p = 0.322). All the patients who died during the study period had renal trauma with associated other organ injuries. None of the patients with isolated renal trauma died during the study. The outcome comparison between both groups was not statistically significant (p = 0.110). ConclusionRenal trauma predominantly occurs in young males, especially due to RTCs followed by fall from height. Focused assessment with sonography in trauma is not reliable in detecting renal injuries, other diagnostic tools such as contrast enhanced computed tomography torso should be considered in diagnosing and grading these injuries. Renal trauma usually does not occur in isolation. Majority are associated with other abdominal and extra abdominal injuries. Most of the times these injuries can be managed nonoperatively, which can achieve a low mortality. The patients who required surgery had high mortality as compared to patients who managed nonoperatively. These patients who required surgery had either severe renal or extra renal trauma and were in hemorrhagic shock. Renal trauma from this large cohort may contribute to improving the quality of care for patients with renal trauma by obtaining knowledge about the patient's characteristics, management, and outcomes.

Stochastic analysis of flexible rotor supported on hydrodynamic bearings

Rotating shaft instability leading to high amplitude vibration is a key problem with a wide range of industrial applications. The purpose of this study is to identify the response statistics for a conceptual model of a flexible shaft supported on hydrodynamic bearings (HDBs) and propose design strategies to reduce the response. A conceptual model of a flexible shaft with three discs supported on the HDBs is developed. A linearised model of the system is developed using the short bearing assumption. A Campbell diagram is developed for the conceptual model to identify the critical speeds wherein a high response is produced. These high responses occur at the rotor speeds corresponding to the synchronous forward whirl and the oil whip. The identified rotor speeds are validated by carrying out a run-up analysis on the test rig. Since the manufacturing process and operating conditions induce uncertainty by varying the eccentricity and the relative phase of the unbalance mass, the influence of the whirling modes on the response is investigated. The nominal positions of the unbalance masses are such that the predominant mode excited is the first mode. Experimentally a scatter plot on the maximum response at the bearing location is identified using six different positions of the eccentric mass. Further, a stochastic analysis using reduced order nonlinear model of the system is carried out. The probability density obtained is compared with a Monte Carlo simulation and the bounds of the experimental results. A control strategy is designed by altering the relative position of the unbalance masses to reduce the excitation of the first mode. The robustness of the strategy is verified by using a stochastic analysis, which indicates a reduction in the response magnitude.

Examining the effect of moderating variables on autonomous public van acceptance model (APVAM).

Autonomous vehicles (AVs) will soon become the primary means of transportation for millions of people. However, the introduction of these vehicles may lead to increased traffic and changes in people's travel patterns. To address this issue, one solution is to promote the use of AVs in a shared and public manner. However, the success of this approach depends on public acceptance of public AVs. If the promoters of public AVs are unaware of how people perceive this technology, it is possible that these vehicles will face failure in the market. Therefore, this paper aims to identify the factors that influence the willingness to use public AVs. To achieve this, an autonomous public van acceptance model (APVAM) was developed by adapting the unified theory of acceptance and use of technology (UTAUT2) through structural equations modeling. In this study, 824 citizens of Tehran participated in a field study and completed an online questionnaire. The research results indicated that the variable of effort expectancy indirectly affects the use of autonomous public vans (APVs), while the variables of performance expectancy, facilitating condition, hedonic motivation, and perceived PUnTrust directly affect their use. The research also found that various factors such as gender, level of education, individualism/collectivism, travel purpose, the dominant travel mode, marital status, occupation, age, household wealth, number of vehicles owned, and the price of the current vehicle of the household have a moderating effect on the APVAM. Furthermore, it was revealed that individuals who primarily use personal or public transport for their daily trips are more influenced by the perceived enjoyment of APVs in increasing their willingness to use these vehicles, compared to those whose predominant mode of travel is walking or cycling.