Search Results (237)

Distinguishing peri-mortem trauma from heat-induced trauma is often a challenging aspect of forensic anthropology casework where fire has been used as a means of concealing evidence. This paper aims to explore the extent to which peri-mortem ballistic trauma characteristics are still present after burning and whether they can be distinguished from heat-induced fractures. This research used Sus domesticus femora and ribs that had been manually defleshed and shot with 7.92 × 57 mm Mauser ammunition at a shooting distance of 3 m, 10 m and 20 m. This type of firearm and ammunition were commonly used in a number of conflicts, such as the Spanish Civil War (1936–1939). The fracture patterns as a result of the ballistic trauma were analysed prior to placing the samples in an electric furnace, where they were heated at a peak temperature of 850 °C for 30 min. Post-burning, each fragment was analysed for ballistic and heat-induced trauma. Following reconstruction, entry and exit wound morphology and radiating fractures remained, with entry wounds being more clearly defined than exit wounds. Ballistic trauma characteristics such as bevelling were still apparent after burning. The results of this study reveal that pre-existing ballistic trauma is still identifiable after bones have been exposed to heat and it is possible to reconstruct the bones to gain a better interpretation. Full article

This study provides a detailed review of the thermal and thermo-hydraulic performance of solar air heaters (SAHs) enhanced through the application of artificial roughness on the absorber plate. Various roughness geometries, such as wire ribs, V-shaped ribs, arc-shaped ribs, and rib-groove patterns, have been analysed to assess their influence on heat transfer enhancement and frictional behaviour. Findings from previous experimental and numerical studies reveal that the incorporation of artificial roughness can increase the Nusselt number by approximately 1.25 to 6.3 times and improve thermal efficiency by 20–35% when compared to smooth absorber plates. The review further highlights that the most effective performance occurs at a relative roughness height (e/D) between 0.02 and 0.05 and within a Reynolds number range of 10,000 to 18,000. Overall, the analysis confirms that artificial roughness is a simple, economical, and highly effective technique to enhance heat transfer and overall efficiency in solar air heater systems. Full article

This study investigates the mechanical behavior and fatigue performance of orthotropic steel bridge decks, with a focus on rib-to-deck welded connections and the impact of geometric symmetry on stress distribution. Two full-scale models with full-penetration butt welds were tested under static compression loads, yielding failure forces of 27 kN (experimental) and 26 kN (analytical), with only a 3% difference. Finite element simulations using ANSYS 16.1 validated these results and enabled parametric studies. Rib plate thicknesses ranging from 5 mm to 9 mm were analyzed to assess their influence on stress distribution and deformation. The geometric ratio h′/tr, which reflects the symmetry of the trapezoidal rib web, was found to be a critical factor in stress behavior. At h′/tr = 38 (tr = 7 mm), compressive and tensile stresses are balanced, demonstrating a symmetric stress field; at h′/tr = 33 (tr = 8 mm), and fatigue performance at the RDW root drops by 47%. Increasing h′/tr improves fatigue life by increasing the number of load cycles to failure. Stress contours revealed that compressive stress concentrates in the rib plate above the weld toes, while tensile stress localizes at the RDW root. The study highlights how symmetric geometric configurations contribute to balanced stress fields and improved fatigue resistance. Multiple linear regression analysis (SPSS-25) produced predictive equations linking stress values to applied load and geometry, offering a reliable tool for estimating stress without full-scale simulations. These findings underscore the importance of optimizing h′/tr and leveraging structural symmetry to enhance resilience and fatigue resistance in welded joints. This research provides practical guidance for improving the design of orthotropic steel bridge decks and contributes to safer, longer-lasting infrastructure. Full article

Background: Fractured ribs remain a significant cause of morbidity and are associated with severe injuries requiring several healthcare resources and may be associated with prolonged hospital stays that may require an ICU facility. In our facility, we have a high burden of patients sustaining rib fractures, and we aim to compare management options, outcomes, and factors associated with mortality from a single center. Methods: A retrospective review was performed on patients who presented with rib fractures at a Level 1 Trauma facility in Johannesburg, undergoing medical or surgical management. The study included data from 1 July 2011 until 31 December 2020. All patients were identified using the Medibank database. STATA Version 18 software was used for all data analysis. A p-value of <0.05 was considered statistically significant. Injuries were subdivided according to the Abbreviated Injury Severity score as follows, Mild = AIS Grade I–II, Moderate = AIS Grade III, Severe AIS Grade IV–V. Results: There was a total of 940 patients. The median age was 45 (IQR: 34–55) years, with 22% female patients in a cohort of 940. The mechanism of injury was blunt in 96%. Most patients (93%) fractured 3/> ribs. Only 4.6% sustained a flail chest. The median SBP was 126 mmHg (IQR:109–144), and the pulse rate was 91 (IQR: 79–108) beats per minute. The mean Injury Severity Score (ISS) and New Injury Severity Score (NISS) were 17 (IQR: 10–29) and 22 (IQR: 14–34), respectively. The most common associated injuries were chest trauma in 42%, combined abdominal and pelvic trauma in 35%, and severe extremity trauma in 37%. The mortality rate was 17% (159/940). Most patients required medical and supportive management, with only 8% undergoing rib plating (76/940). The mean length of stay was 14 days (IQR: 6–25). Statistically significant factors associated with mortality were rib fractures 3≥, flail chest, higher ISS, severe head, neck, chest, abdomen and pelvis injuries (p-value 0.001) and severe extremity injury (p-value 0.006). Conclusions: Rib fractures remain a common pathology in the trauma population, and these patients can have significant associated injuries. With an appropriate multidisciplinary approach, our study found an 83% survival rate, and only 8% of patients requiring surgical intervention. Poor outcomes in patients are directly linked to the number of ribs involved, the injury severity score, associated injuries, and advanced age. Full article

Background: While prostate-specific membrane antigen (PSMA)-targeted imaging has revolutionized metastatic detection, unspecific bone uptake (UBU)—particularly in the ribs—is a common but diagnostically challenging finding in prostate cancer (PCa) patients. This review aims to synthesize current evidence on PSMA-avid rib lesions in PCa and to propose a structured approach for differentiating true metastases from benign mimics. Methods: A comprehensive literature search across PubMed, EMBASE, Scopus, and Web of Science identified relevant studies on PSMA imaging interpretation, tracer-specific patterns, rib lesion morphology, and clinical correlates. Data on uptake intensity, CT features, lesion number, location, tracer type, patient-specific risk factors, and follow-up behavior were extracted and analyzed. Results: Most solitary rib lesions are benign, particularly in low-risk patients or when located in the anterior/lateral arcs. Metastatic lesions are more likely to present as multiple foci, show cortical destruction on CT, exhibit high uptake intensity, and occur in patients with elevated PSA, high Gleason score, or ongoing androgen deprivation. ¹⁸F-PSMA-1007 is especially prone to UBU in the ribs compared to ⁶⁸Ga-PSMA-11. Based on these variables, we propose a clinical decision tree to guide interpretation of PSMA-avid rib lesions. Conclusions: Accurate interpretation of rib lesions on PSMA PET/CT requires a multimodal, context-sensitive approach. Our diagnostic decision tree guides precise differentiation of benign versus metastatic rib lesions, enhancing staging accuracy and clinical decision-making. Biomarker-guided therapies offer potential for personalized treatment, though rib-specific validation remains a critical need. Full article

This research presents an experimental study on a scaled prototype of a bladeless wind turbine that operates based on the principle of vortex-induced vibrations (VIV-BWT) with the implementation of bio-inspired design of a columnar-cactus type mast. The aerodynamic performance of columnar-cactus type masts with different numbers of ribs was investigated and compared with that of a conventional cylindrical mast. The objective of this novel proposal is to maximize wind energy conversion efficiency through vortex-induced vibrations, thereby enhancing energy generation. The present study focuses on the geometry of the columnar-cactus type mast as a vortex generator, which significantly influences the performance of this type of VIV wind energy harvester. The findings reveal that the geometric configuration of the cactus-inspired mast and the mast angle promote vortex formation, leading to higher lift coefficients and forces. Consequently, this results in greater vortex-induced vibration magnitudes. For instance, at a wind speed of 6.0 m/s and a mast angle of 0°, the 6-rib cactus-type mast exhibits 12 times greater VIV amplitude compared to the conventional cylindrical mast, while the 5-rib and 7-rib cactus-type masts show 2.4- and 2.2-times greater amplitudes, respectively. However, for wind speeds below 5 m/s, the cylindrical mast demonstrates superior VIV performance. Full article

The number of thoracolumbar vertebrae (NTLV) and the number of ribs (NR) are economically important traits in pigs due to their influence on carcass length and meat yield. Although VRTN is an established key gene, it fails to fully account for population-level variation in vertebral count, necessitating a further exploration of its genetic mechanisms. Given the efficacy of crossbred populations in mapping the genetic determinants of phenotypic variation, we analyzed 439 pigs from a Landrace × Yorkshire cross. Genotyping was performed via a 50 K SNP chip. Both NTLV and NR showed high heritability (0.700 and 0.752, respectively), while the number of lumbar vertebrae (NLV) showed limited variation (92.5% of pigs had NLV = 6). Using the BLINK model, four significant loci were identified. The most significant SNP, rs3469762345, located in the intergenic region between ABCD4 and VRTN, corresponds to a previously known QTL. Additionally, three novel variant sites (rs81211244, rs81347323, and rs81416674) were identified within or near the ALDH7A1, PTPRT, and PAK1 genes, which are known to play a role in bone development. This study uncovers novel swine candidate genes associated with vertebral and rib number variation, subsequently facilitating targeted research into their molecular mechanisms. Full article

Steel–ultra-high-performance concrete (UHPC) composite beams with small-rib-height perfobond strip connectors (SRHPBLs) exhibited advantages of light weight and high bearing capacity, demonstrating the potential for applications of UHPC in bridge engineering. During service stages, the composite beams were usually under combined tension–shear loads, rather than pure shear loads. Nevertheless, there were research gaps in the static behavior of SRHPBLs embedded in UHPC under combined tension–shear loads, which limited their applications in practice. To address this issue, systematic experimental and theoretical analyses were conducted in the present study, considering the test variables of tension–shear ratio, row number, and strip number. It was demonstrated that the tension–shear ratio had less effect on ultimate shear strength, initial shear stiffness, and ultimate slip of SRHPBLs. When the tension–shear ratio was increased from 0 to 0.42, the shear capacity, initial shear stiffness, and slip at peak load of SRHPBLs decreased by 24.31%,19.02%, and 22.00%, respectively. However, increasing the row number and strip number significantly improved the shear performance of SRHPBLs. Compared to the single-row specimens, the shear capacity and initial shear stiffness of the three-row specimens increased by an average of 92.82% and 48.77%, respectively. The shear capacity and initial shear stiffness of the twin-strip specimens increased by an average of 103.84% and 87.80%, respectively, compared to the single-strip specimens. Finally, more accurate models were proposed to predict the shear–tension relationship and ultimate shear capacity of SRHPBLs embedded in UHPC under combined tension–shear loads. Full article

An analytical method is developed to evaluate the modal density of a fluid-loaded stiffened plate with a damping layer. The effects of the damping layer, ribs, and fluid load on the structure’s equivalent bending rigidity and surface density are analyzed. The vibration equation is obtained by applying the Hamilton principle, and the modal density is calculated by counting modes in the specific band. The modal density calculation method for both ribbed-type plates and uniform-type plates is verified through numerical simulation. The increase in the number of ribs has made the rib-off frequency at which the effect of the ribs can be neglected become higher, since the wavelength needs to be shorter when the ribbed plate can be treated as a uniform-type plate. The introduction of the damping layer has slightly increased the modal density compared to the uniform plate. In contrast, the introduction of fluid load has dramatically increased the modal density of the corresponding base plate in the low-frequency domain, and the effect of the fluid load can be ignored in the high-frequency domain. Full article

The shear tests are conducted on six precast segmental concrete beams (PSCBs) in this paper. A new specimen design scheme is presented to compare the effects of segmental joints on the shear performance of PSCBs. The failure modes, shear strength, structural deflection, stirrup strain, and tendon stress are recorded. The factors of shear span ratio, the position of segmental joints, and hybrid tendon ratio are focused on, and their effects on the shear behaviors are compared. Based on the measured responses, the shear contribution proportions of concrete segments, prestressed tendons, and stirrups are decomposed and quantified. With the observed failure modes, the truss–arch model is employed to clarify the shear mechanism of PSCBs, and simplified equations are further developed for predicting the shear strength. Using the collected test results of 30 specimens, the validity of the proposed equations is verified with a mean ratio of calculated-to-test values of 0.96 and a standard deviation of 0.11. Furthermore, the influence mechanism of shear span ratio, segmental joints, prestressing force, and hybrid tendon ratio on the shear strength is clarified. The increasing shear span ratio decreases the inclined angle of the arch ribs, thereby reducing the shear resistance contribution of the arch action. The open joints reduce the number of stirrups passing through the diagonal cracks, lowering the shear contribution of the truss action. The prestressing force can reduce the inclination of diagonal cracks, improving the contribution of truss action. The external unbonded tendon will decrease the height of the arch rib due to the second-order effects, causing lower shear strength than PSCBs with internal tendons. Full article

Based on the engineering background of a new type of segmental-assembled steel temporary beam buttress, the fatigue strength evaluation method of the steel box girders with open longitudinal ribs was taken as the research objective. The fatigue stress calculation analysis and the full-scale fatigue loading test for the steel box girder local component were carried out. The accuracy of the finite-element model was verified by comparing it with the test results, and the rationality of the fatigue strength evaluation methods for welded joints was deeply explored. The results indicate that the maximum nominal stress occurs at the weld toe between the transverse diaphragm and the top plate at the edge of the loading area, which is the fatigue-vulnerable location for the steel box girder local components. The initial static-load stresses at each measuring point were in good agreement with the finite-element calculation results. However, the static-load stress at the measuring point in the fatigue-vulnerable position shows a certain decrease with the increase in the number of cyclic loads, while the stress at other measuring points remains basically unchanged. According to the finite-element model, the fatigue strengths obtained by the nominal stress method and the hot-spot stress method are 72.1 MPa and 93.8 MPa, respectively. It is reasonable to use the nominal stress S-N curve with a fatigue life of 2 million cycles at 70 MPa and the hot-spot stress S-N curve with a fatigue life of 2 million cycles at 90 MPa (FAT90) to evaluate the fatigue of the welded joints in steel box girders with open longitudinal ribs. According to the equivalent structural stress method, the fatigue strength corresponding to 2 million cycles is 94.1 MPa, which is slightly lower than the result corresponding to the main S-N curve but within the range of the standard deviation curve. The research results of this article can provide important guidance for the anti-fatigue design of welded joints in steel box girders with open longitudinal ribs. Full article

Carcass and meat quality traits are critical in pig breeding and production. Estimating genetic parameters for these traits is a vital aspect of breeding engineering, as accurate genetic parameters are essential for estimating breeding values, predicting genetic progress, and optimizing breeding programs. This study was conducted on a population of 461 Yorkshire pigs from the same breeding farm, which were slaughtered to assess nine carcass traits and seven meat quality traits, followed by descriptive statistical analysis. Additionally, we estimated the genetic parameters of these traits using genomic information based on 50K chip data. The results indicated that sex significantly affected most carcass and meat quality traits. Carcass traits including carcass length indicators (h² = mean 0.35), backfat thickness indicators (h² = mean 0.36), eye muscle area (h² = 0.28), and the number of rib pairs (h² = 0.28) exhibited medium to high heritability. Carcass length indicators showed high genetic correlations with backfat thickness indicators (r = mean −0.49) and the number of rib pairs (r = mean 0.63), while high negative genetic correlation (r = −0.72) was noted between eye muscle area and the number of rib pairs. Meat quality traits also displayed medium to high heritability, expect for pH value measured within one hour post-slaughter (h² = 0.12). Drip loss indicators had higher genetic correlations with pH (r = mean −0.73) than with meat color indicators (r = mean 0.22). These findings may provide a theoretical reference for genetic evaluation and breeding in the Yorkshire pig population. Full article

The present study investigates the influence of the configurations of anchor bolts and stiffeners on the monotonic response under moment conditions in the major axis and compression force of partial-strength exposed column base plate connections in order to ameliorate their response, limiting the number of welded details. Parametric finite element simulations were performed based on models calibrated against experimental results available from the recent literature. The results show the efficiency of the investigated configurations, namely, (i) the presence of rib stiffener results in high stiffness and strength with a reduction in ductility; (ii) the linear pattern of anchor bolts (e.g., rectangular distribution) is characterized by the limited contribution of the outer anchor bolts to the overall resistance of the connection; (iii) the trapezoidal pattern of the anchor bolts exhibit a better mechanical performance as well as their efficiency; and (iv) the increase in compression force influences the mechanical response of the base connection with an increase in both resistance and rigidity until the column is stable against the moment–axial force interaction. Full article

In order to explore the axial compression performance of external steel rib ring restraint waste-steel-fiber-reinforced concrete-filled steel tubes (ERWCFSTs), 18 short-column axial compression tests were conducted. The effects of the number of rib rings, rib ring spacing, rib ring setting position, and waste steel fiber (WSF) content on the axial compression performance of the columns were analyzed. The results show that the concrete-filled steel tube (CFST) short columns with rib rings were strengthened, the specimens were mainly characterized by drum-shaped failure, and the buckling was concentrated between the rib rings. Without rib ring specimens, the steel tube is unable to resist the rapid increase in lateral expansion, leading to buckling initiation near the bottom of the specimens. The columns with rib rings exhibited a minimum increase of 32.5% and a maximum increase of 53.17% in load-bearing capacity compared to those without rib rings, with an average improvement of 37.78%. The columns achieved the best ductility when the rib ring spacing was 50 mm. When the rib ring spacing remained constant, columns with a number of rib rings no less than the height-to-diameter ratio (H/D) demonstrated more uniform stress distribution and optimal confinement effects. For a fixed number of rib rings, specimens with rib ring spacing between H/8 and H/4 showed significant improvements in both load-bearing capacity and ductility. The confinement effect was better when the rib rings were positioned in the middle of the column height rather than near the ends. The incorporation of WSF resulted in a minimum increase of 2.86% and a maximum increase of 10.49% in column load-bearing capacity, indicating limited enhancement. However, WSF improved the ductility performance of the columns by at least 10%. Combined with theoretical analysis and experimental data, a formula for calculating the bearing capacity of ERWCFSTs was established. Full article

To improve the convective heat transfer in internal cooling channels of heavy-duty gas turbine blades, this study experimentally and numerically investigates the thermal performance of rectangular channels with hybrid pin-fins and micro V-ribs turbulators. The transient thermochromic liquid crystal (TLC) technique and ANSYS 2019 R3 (ICEM CFD 2019 R3, Fluent 2019 R3, CFD-Post 2019 R3) were employed under Reynolds numbers ranging from 10,000 to 50,000, with the numerical model rigorously validated against experimental data (the maximum RMSE is 2.5%). It is found that hybrid pin-fins and continuous V-ribs configuration exhibits the maximum heat transfer enhancement of 27.6%, with an average friction factor increase of 13.3% and 21.9% improvement in thermal performance factor (TPF) compared to the baseline pin-fin channel. In addition, compared to the baseline pin-fin channel, hybrid pin-fins and broken V-ribs configuration exhibits average heat transfer enhancement (Nu/Nu0) of 24.4%, an average friction factor increase of 7.2% and 22.5% improvement across the investigated Reynolds number range (10,000~50,000) based on computational results. The synergistic effects of hybrid pin-fin and micro V-rib structures demonstrate superior coolant flow control, offering a promising solution for next-generation turbine blade cooling designs. This work provides actionable insights for high-efficiency gas turbine thermal management. Full article