Number Of Ribs Research Articles

Superhydrophilic surfaces with hierarchical groove structure for efficient fog collection

Many biological surfaces with hierarchical microstructures exhibit obvious fog collection abilities. However, it is difficult to effectively fabricate a microstructured metal surface with fog collection performance using a simple but flexible method. Inspired by the abilities of microstructures of Sarracenia trichomes to capture fog and transport water, a series of hierarchical groove surfaces with the fog collection property were fabricated by wire electrical discharge machining (WEDM) method, and the fabricated surfaces showed the obvious superhydrophilicity. Moreover, the results show that the fabricated surface with the hierarchical groove structure had better water transport performance and higher fog collection efficiency compared with the smooth surface, and the abilities of water transport and fog collection are related to the number of low ribs on the surface with the hierarchical microgroove. The microstructure metal materials obtained in this study not only open up the potential applications of WEDM in fog collection, but also have wide application prospects in the fields of microfluidic system, biomedicine, and biological excitation system.

Predicting Maximal Costal Cartilage Graft Size for Laryngotracheal Reconstruction.

Current methods of assessing rib cartilage dimensions for laryngotracheal reconstruction (LTR) are inexact, making surgical planning difficult. The purpose of this study was to determine the most appropriate rib for costal cartilage graft LTR to minimize the number of ribs harvested and improve surgical outcomes. Retrospective review. Computed tomography imaging of chest scans in 25 children aged 1 to 18 years was evaluated. The lengths and widths of medial and lateral cartilaginous segments of ribs 4 to 7 were measured bilaterally. Right and left cartilaginous rib dimensions were compared using a two-sample t-test. Linear mixed-effect regression was performed to develop models quantifying the relationship between rib size and patient height, rib side, and rib number. Regression analysis established strong models for medial rib length (R2 =0.89) and for medial and lateral rib width (R2 =0.71, 0.77, respectively). There was no difference in rib dimensions across chest sides. Rib length and width increased with child height. Total cartilaginous rib length increased from superiorly to inferiorly, primarily due to an increase in the dimensions of the medial portion of each rib. Cartilaginous rib lengths and widths were associated with patient height, with taller children having longer ribs. Inferior ribs were longer than superior ribs, suggesting that inferior ribs may be preferred for LTR. There was no difference in cartilaginous rib length across chest side. Results may help surgeons with preoperative planning. NA Laryngoscope, 132:1682-1686, 2022.

Numerical analysis of flow and heat characteristic around micro-ribbed tube in heat exchanger system

In order to improve the energy utilization rate, this paper analyzes the flow around the cylinder in the tube-row channel heat exchanger through numerical simulation. Effects of micro-rib structure types (vertical rib and ring rib), number of ribs (N = 0, 4, 6, 8), height of ribs (H = 2, 3, 4 mm), pitch diameter ratio (ST/D = 1.5, 2, 2.5), mass fractions (ω = 0–0.5%) and Reynolds numbers (Re = 514–1205) on the flow and heat transfer characteristics of tube-row channel heat exchangers are analyzed. Results showed that TiO2-H2O nanofluids can improve the comprehensive performance of heat exchanger, and when the mass fraction is 0.4%, the tube-row channel heat exchanger has the best performance. For heat exchangers with different types and structural parameters, the adjustment of the number of ribs, the height of ribs, the ratio of transverse pitch diameter and the use of nanofluids can increase Nusselt numbers by 53.63%, 57.25%, 52.38% and 12.93% at maximum, respectively.

A new species of Cetopsorhamdia (Siluriformes: Heptapteridae) from the Upper Amazon River basin

A new species of Cetopsorhamdia is described from material collected on rapid inventories and ichthyological expeditions in the Amazon region of Peru, Ecuador and Colombia. The new species can be differentiated from all other species of Cetopsorhamdia by the colouration pattern on fins, number of vertebrae, number of ribs, level insertion of dorsal fin, number of rays on dorsal and pectoral fin, osteological characters and several other morphometric characters. The new species is distributed along tributaries of the upper Amazon River basin in Peru, Colombia and Ecuador.

Epitypification of the Linnaean name Crepis bursifolia (Asteraceae)

AbstractThe epitypification of the Linnaean name Crepis bursifolia is discussed. An illustration from Boccone's Museo di piante rare della Sicilia, Malta, Corsica, Italia, Piemonte, e Germania was correctly designated as lectotype by Jiménez López & al. in 2013 according to Art. 7.11 of the ICN. However, this image lacks some of the important characters required for a critical identification of the species (i.e., hairiness of receptacle, length of achenes, number of ribs on the achene surface, and presence of a distinct apical beak on the achene). Following Art. 9.9 of the ICN, an epitype deposited at HFLA is selected to serve as an interpretative type of the lectotype of C. bursifolia.

Effects of fiber type and specimen thickness on flexural behavior of ultra-high-performance fiber-reinforced concrete subjected to uniaxial and biaxial stresses

In this study, we investigated the effects of steel fiber type and specimen thickness on the uniaxial and biaxial flexural behaviors of ultra-high-performance fiber-reinforced concrete (UHPFRC). For this purpose, three types of steel fibers (straight, three-times twisted, and six-times twisted) and three thicknesses of specimen (24, 48, and 72 mm) were used. The test results indicated that, owing to the larger perimeter of the triangular shape and mechanical anchorage effect, the twisted steel fibers exhibited better pullout resistance than the straight steel fiber with a circular shape, and its effectiveness increased with the number of ribs. In contrast, the best flexural behavior of UHPFRC was observed when the straight steel fiber was used under both uniaxial and biaxial stress states, and the six-times twisted steel fiber exhibited the worst flexural performance owing to the excessive bond strength of the composites. The uniaxial and biaxial flexural strengths of UHPFRC were insignificantly influenced by the sample thickness; however, the normalized toughness decreased with an increase in the thickness. A higher flexural strength, normalized toughness up to the peak, and deformability were observed under the biaxial flexural stress state than those under the uniaxial flexural stress state. The use of twisted steel fibers was more effective for slabs subjected to biaxial flexural stress than that for uniaxial beams.

A new phylogeny of the cladoxylopsid plexus: contribution of an early cladoxylopsid from the Lower Devonian (Emsian) of Quebec.

Cladoxylopsids formed Earth's earliest forests and gave rise to the ancestors of sphenopsids and ferns. Lower Devonian (Emsian) strata of the Battery Point Formation (Quebec, Canada) contain new anatomically preserved cladoxylopsids, one of which is described in this article. To assess the phylogenetic position of this fossil and address questions of cladoxylopsid phylogeny, we conducted a comprehensive phylogenetic study. Permineralized axes were studied in serial sections using the cellulose acetate peel technique. We evaluated phylogenetic relationships among cladoxylopsids using a data set of 36 new morphological characters and 31 species, in parsimony-constrained analyses. We describe Adelocladoxis praecox gen. et sp. nov., a cladoxylopsid with small actinostelic axes bearing dichotomously branched, helically arranged ultimate appendages and fusiform sporangia. Adelocladoxis provides the oldest evidence of cladoxylopsid anatomy, including ultimate appendages and sporangia. In agreement with non-phylogenetic classification schemes, our phylogenetic analysis resolves a basal grade of iridopterids and a clade of cladoxylopsids s.s., which includes a pseudosporochnalean cladoxylopsid clade, a cladoxylalean cladoxylopsid clade, and Adelocladoxis. Our phylogenetic analysis illuminates aspects of tempo and mode of evolution in the cladoxylopsid plexus. Originating prior to the Emsian, cladoxylopsids reached global distribution by the Frasnian. Iridopterids and cladoxylopsids s.s. radiated in the Emsian-Eifelian. The sequence of character change recovered by our phylogeny supports a transition from actinostelic protosteles to dissected steles, associated with an increase in xylem rib number and medullation generating a central parenchymatous area.

Self-Heating Mould for Composite Manufacturing.

The shipbuilding industry, engine manufacturing, aviation, rocket and space technology are promising fields of application for polymeric composite materials. Shape-generating moulding tools with internal heating are used for the creation of a more economically viable method of moulding of internally heated composite structures. The use of a fine-fibered resistive structure in the heated tools allows implementation of effective heating of the composite and elimination of the need for expensive and energy-intensive heating equipment. The aim of this paper was the reduction of energy consumption for internally heated moulding tools by choosing the optimal parameters for their resistive layer. A method for determination of the parameters of the moulding tool resistive layer was developed. This method allows calculation of the heating layer parameters and implementation of the specified time–temperature regime for moulding of the composite structure. It was shown that energy saving for the heated fiberglass shape-generating moulding tools was from 40 to 60%. It was found that the increase in the thickness of the moulded package of the polymeric composite material resulted not only in a higher supplied power for the heating system, but also in a complication of the method for system control, because of the growing exothermic effect of the binder curing reaction. For composite products based on Hysol EA 9396 binder, thicknesses more than 4 mm are critical, because it is not possible to cope with the self-heating effect only by cooling with ambient air already utilized at the twentieth minute of the moulding process. The influence of the physical and mechanical characteristics of the moulding tool material and stiffening ribs was analysed in terms of energy consumption and controllability of the heating system. Fiberglass shows the lowest energy consumption. Heating of the aluminium and steel moulding tools for the same purpose will require 20% and 45% more power, respectively. An increase in the number of stiffening ribs has a strong effect on the heat removal of the heating system. With a small number of aluminium ribs it is not possible to maintain the specified temperature–time regime for a fiberglass moulded package of 5 mm thick with the use of the equipment. However, when the number of stiffeners is increased to 10, the exothermic effect of the reaction becomes smoother and then the heating equipment can cope with the task. An experimental prototype of heating equipment of moulding tools for the manufacturing of structures of polymeric composite materials, as well as a flexible thermal blanket for repair of non-separable structures, were developed. The results can be the basis for a new method of optimal design of parameters of moulding tool structure at minimal heat removal to the environment.

Energy absorption of fully clamped multi-cell square tubes under transverse loading

This paper investigates energy absorption performance of multi-cell tubes considering the influence of axial constrain in bending process Firstly, three-point-bending tests and fully clamped bending tests were conducted. Experimental results showed that the energy absorption of tubes increased to 2.5–3 times if the end of the tube is constrained. Based on the FE model verified by experiments, the effect of rib direction and rib number is investigated under fully clamped condition. Results show that the multi-cell tubes with rib parallel to the load direction (MT-Y0Zn) have better energy absorption performance than that with rib perpendicular to the load direction (MT-YnZ0), especially in the frontal part of bending process. Meanwhile, following with the increase of rib number, specific energy absorption (SEA) of MT-Y0Zn increases gradually, while SEA of MT-YnZ0 remains almost unchanged. Considering the fact that MT-Y0Zn shows better energy absorption performance, theoretical model of MT-Y0Zn is established and highly consistent with FE model. Finally, the influence of thickness and cross-section size is discussed. SEA increases with increase of cross-section and remains unchanged with increase of thickness as predicted by theory. However, when cross-section exceeds 80 mm or thickness is smaller than 1 mm, local denting caused by shear force decreased SEA significantly.

Survival and racing performance after surgical treatment of rib fractures in foals.

To evaluate the short and long-term outcomes of foals treated surgically for fractured ribs and variables that may affect outcome. Retrospective. Seventy-three equine neonates with surgically repaired fractured ribs. Medical records were reviewed to include sex, breed, the side of thorax affected, number of ribs fractured, co-morbidities directly associated with rib fracture, and surgical technique used. Short-term outcome was defined as survival to discharge. Long-term outcome was whether or not they started a race. Race records of maternal siblings were obtained for comparison. Seventy-three neonates underwent surgery for fractured ribs. Fifty-seven neonates (78%) survived to discharge from the hospital. Rib fractures were more commonly observed in colts and in the left hemithorax (61% and 57%, respectively). Sex, side affected, number of ribs fractured, co-morbidities, number of ribs repaired, and surgical technique did not affect the short- or long-term outcomes. Thirty-five of 57 (61%) foals treated surgically for rib fractures that survived to discharge started a race compared to 173 of 257 (67%) of maternal siblings that raced. Short- and long-term outcome were not affected by co-morbidities, surgical technique, or number of fractured ribs. Neonates with surgically repaired fractured ribs had a good prognosis for survival and and those that survived had a similar chances of starting a race compared to maternal siblings.

Thermal performance enhancement and prediction of narrow liquid cooling channel for battery thermal management

A novel heat transfer device for narrow space was proposed to meet high power battery heat dissipation. Based on the battery heat generation data, the heat transfer enhancement mechanism of the secondary flow pattern is studied. Then establish the general heat transfer correlation for this liquid-cooled structure with a specific aspect ratio. The results show that the channel with rib angle of 90° has higher Nu as well as ƒ and can achieve the same heat transfer performance with smaller flow rate. This is due to its transition flow pattern of twist-tape vortex and stagnant vortex, which can enhance the contact heat transfer performance of mainstream cold fluid while inhibiting the growth of boundary layer. The increase in rib number gradually decreases the gain of Nu with a minimum increment of less than 1%; while ƒ almost gradually increases with a common difference of 0.05. From the perspective of heat transfer and energy saving, increasing rib number does not essentially improve the heat transfer performance. Because the flow field at different rib number is just a mapping of the complete flow field at the corresponding length. Based on the above data, for the flat channel with aspect ratio of 10:3 in narrow space, the second-order general heat transfer correlation for different hydraulic diameter is established considering the Re, dynamic viscosity, rib angle and rib number. Finally, the coefficient of determination (R2) of the correlation is 0.9973, which can provide guidance for battery thermal management engineering applications.

Vibration of rectangular plates stiffened by orthogonal beams

This paper presents a new analytical solution for the vibration response of plates stiffened by orthogonal beams using a double finite sine integral transform technique. The compatibility conditions at the coupling interfaces and the boundary conditions of the plate are automatically defined in the transform. It is shown that the analytical model can accommodate various combinations of clamped and simply supported boundary conditions. The analytical model is then used to study the reproduction of the vibration response of an orthotropic plate. It is shown that an orthogonally ribbed isotropic plate can produce a closely matching vibration response to that of an orthotropic plate by carefully choosing an appropriate number of ribs and the rib properties in each plate direction.

Mapping of common rib fracture patterns and the subscapular flail chest associated with operative scapula fractures.

Rib fractures occur in approximately 10% of trauma patients and are associated with more than 50% of patients with scapula fractures. This study investigates the location and patterns of rib fractures and flail chest occurring in patients with operatively treated scapula fractures. Novel frequency mapping techniques of rib fracture patterns in patients who also injure the closely associated scapula can yield insight into surgical approaches and fixation strategies for complex, multiple injuries patients. We hypothesize that rib fractures have locations of common occurrence when presenting with concomitant scapula fracture that requires operative treatment. Patients with one or more rib fractures and a chest computed tomography scan between 2004 and 2018 were identified from a registry of patients having operatively treated scapula fractures. Unfurled rib images were created using Syngo-CT Bone Reading software (Siemens Inc., Munich, Germany). Rib fracture and flail segment locations were marked and measured for standardized placement on a two-dimensional chest wall template. Location and frequency were then used to create a gradient heat map. A total of 1,062 fractures on 686 ribs were identified in 86 operatively treated scapula fracture patients. The mean ± SD number of ribs fractured per patient was 8.0 ± 4.1 and included a mean ± SD of 12.3 ± 7.2 total fractures. Rib fractures ipsilateral to the scapula fracture occurred in 96.5% of patients. The most common fracture and flail segment location was ipsilateral and subscapular; 51.4% of rib fractures and 95.7% of flail segments involved ribs 3 to 6. Patients indicated for operative treatment of scapula fractures have a substantial number of rib fractures that tend to most commonly occur posteriorly on the rib cage. There is a pattern of subscapular rib fractures and flail chest adjacent to the thick bony borders of the scapula. This study enables clinicians to better evaluate and diagnose scapular fracture patients with concomitant rib fractures. Diagnostic test, level IV.

Are rib fractures stable? An analysis of progressive rib fracture offset in the acute trauma setting.

Rib fractures serve as both a marker of injury severity and a guide for clinical decision making for trauma patients. Although recent studies have suggested that rib fractures are dynamic, the degree of progressive offset remains unknown. The purpose of this study was to further characterize the change that takes place in the acute trauma setting. A 4-year (2016-2019) retrospective assessment of adult trauma patients with rib fracture(s) admitted to a level I trauma center was performed. Initial and follow-up computed tomography scans were analyzed to determine the magnitude of offset. Relevant clinical course variables were examined, and location of chest wall instability was examined using the difference of interquartile range of median change. Statistical Product and Services Solutions (Version 25, IBM Corp. Armonk, NY) was then used to generate a neural network-multilayer perceptron that highlighted independent variable importance. Fifty-three patients met the inclusion criteria for severe injury. Clinical course variables that either trended or significantly predicted the occurrence of progressive offset were Abbreviated Injury Scale Thoracic Scores (3.1 ± 0.4 no progression vs. 3.4 ± 0.6 yes progression; p = 0.121), flail segment (14% no progression vs. 43% yes progression; p = 0.053), and number of ribs fractured (4 [2-8] no progression vs. 7 [5-9] yes progression; p = 0.023). The location of progressive offset largely corresponded to the posterolateral region as demonstrated by the differences of interquartile range of median change. The neural network demonstrated that ribs 4 to 6 (normalized importance [NI], 100%), the posterolateral region (NI, 87.9%), and multiple fractures per rib (NI, 66.6%) were valuable in predicting whether progressive offset occurred (receiver operating characteristic curve - area under the curve = 0.869). Rib fractures are not stable, particularly for those patients with multiple fractures in the mid-to-upper ribs localized to the posterolateral region. These findings may identify both trauma patients with worse outcomes and help develop better management strategies for rib fractures. Prognostic and epidemiological, level III.

146. A novel vertebral numbering system for identifying congenital anomalies of the spine using full spine radiographs with the EOS imaging system

<h3>BACKGROUND CONTEXT</h3> The numbering of vertebral transitional anatomy can be challenging and controversial. Disagreement exists on how to best report anomalous vertebra and which imaging modality (CT, MRI, X-ray, etc) is most consistent. For these reasons, there is often a discrepancy in the numbering of transitional levels between radiologists and surgeons. Moreover, correlating levels identified intraoperatively by fluoroscopy with inconsistently numbered vertebrae on preoperative MRI or CT is arduous. Errors in numbering can have devastating implications for patients. A simple and accurate vertebral numbering system that can be applied to routine imaging is needed. <h3>PURPOSE</h3> The purpose of this study was to describe a novel and more simplified vertebral numbering system that can be used amongst surgeons and radiologists. <h3>STUDY DESIGN/SETTING</h3> A retrospective imaging study analyzing full-length spine X-rays was performed with the approval of a Colorado Multiple Institutional Review Board (COMIRB protocol:17-1920). <h3>PATIENT SAMPLE</h3> A total of 5,422 images were obtained that included all adult patients who presented to the Spine Center at the University of Colorado and obtained full-spine X-rays using the EOS imaging system between January 31st of 2018 and March 31st of 2020. Images from the same patient at multiple time points were excluded and 3,250 unique patient images were included in our study. After the initial period of data collection, 103 images were excluded from the final analysis due to poor image quality or missing image files. <h3>OUTCOME MEASURES</h3> Total presacral mobile segments were identified and counted using 24 as the number found in conventional spinal anatomy. The total number of ribs were counted for each patient including hypoplastic ribs, and the level of the first-ribbed vertebrae and last-ribbed vertebrae were recorded. <h3>METHODS</h3> Image analysis was conducted by five experienced researchers. The results were reviewed and verified by the senior authors. Any disagreements were reviewed and resolved by two board-certified musculoskeletal radiologists. Final results were evaluated and a novel vertebral numbering system with the lowest probability of error was agreed upon. <h3>RESULTS</h3> In our study cohort, 91.1% (2,868/3,147) demonstrated the conventional 24 presacral mobile segments, whereas 3.3% (104) had 23 presacral mobile segments, 5.5% (174) had 25, and 0.03% (1) had 26. Transitional anatomy, as defined by a number of presacral segments other than 24, was noted in 8.8% (279) of the total number of patients. Within this same group, the majority (94.6%; 2,976) had 12 ribs (including hypoplastic ribs), 4.5% (143) had 11 ribs, and 0.88% (28) had 13 ribs. Just 3.5% (112) had incomplete or hypoplastic ribs. Furthermore, 1.8% (56) of patients had both transitional anatomy and an abnormal number of ribs, with the pattern of transitional anatomy and 11 ribs being the most common combination identified. Considering the first nonribbed vertebrae as the first lumbar vertebrae yielded the lowest probability of a numbering error. <h3>CONCLUSIONS</h3> We are proposing a novel vertebral numbering system that yields the lowest probability of error in reporting anomalous anatomy which can be applied to routine cervical, thoracic, and lumbar radiographs. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

Optimizing surgical stabilization of rib fractures using intraoperative ultrasound localization.

Surgical stabilization of rib fractures (SSRF) significantly improve the outcomes of patients with rib fractures. Ultrasound is a specific modality for localizing rib fractures. We hypothesized that use of perioperative ultrasound localization of fracture sites optimizes surgical approach and clinical outcomes. We performed a retrospective cohort study of adult patients undergoing SSRF and compared those with and without adjunctive perioperative ultrasound fracture localization. Our primary outcome was improved surgical efficiency as measured by incision length and total operative time. Secondary clinical outcomes included numeric pain score on follow-up visit and daily morphine milligram equivalent prescribed within 30 days from discharge. We performed 49 surgical rib fixations between 2015 and 2020; of which, 13 (26.5%) additionally underwent ultrasound localization (26.5%). There were no significant differences between groups in age, sex, number of ribs repaired, or days till surgery. More patients in the ultrasound group had nonflail chest wall injury (76.9% vs. 27.8%, p = 0.003). Use of perioperative ultrasound was associated with shorter incision length (median, 9 vs. 15.5 cm; p = 0.0001), shorter operative time (median, 120 vs. 174 minutes; p = 0.003), less daily morphine milligram equivalent (25 vs. 68 mg, p = 0.009), and reduced numeric pain score on follow up (median, 4 vs. 7, p = 0.05). Use of perioperative ultrasound localization of rib fractures to optimize surgical approach for SSRF was associated with reduced incision length, operative time, and opioid requirements on patient discharge. We recommend considering routine perioperative localization to improve surgical approach and efficiency during SSRF. Therapeutic, level IV.

Numerical Investigation of Hydraulic-Thermal Performance for a Double-Pipe Heat Exchanger Equipped with 45°-Helical Ribs

In this paper, the hydraulic-thermal performance of a double-pipe heat exchanger equipped with 45°-helical ribs is numerically studied. The ribbed double-pipe heat exchanger is modelled using three heights (H = 0, 2.5, 3.75, 5 mm) of 45°-helical ribs. Two numbers (4-ribs and 8-ribs) of 45°-helical ribs are attached on the outer surface of the inner pipe of the counter-flow double-pipe heat exchanger and compared with a smooth double-pipe heat exchanger. Three-Dimensional computational fluid dynamics (CFD) model for a laminar forced annular flow is performed in order to study the characteristics of pressure drop and convective heat transfer. In addition, the influence of rib geometries and hydraulic flow behaviour on the thermal performance is system-atically considered in the evaluations. The annular cold flow is investigated with the range of Reynolds numbers from 100 to 1000, with three heights of ribs at the same width (W = 2 mm) and inclined angles of (θ = 45°).The results illustrate that the average Nusselt number and pressure drop increase with an in-creasing number of ribs, the height of ribs and Reynold number, while the friction factor decreas-es with increasing Reynolds numbers. The percentage of averaged Nusselt number enhancement for three rib heights (H = 2.5, 3.75 and 5 mm) at 4-ribs is (34%, 65% and 71%), respectively, While for 8-ribs the enhancement percentage is (48%, 87% and 133%) as compared with the smooth double-pipe heat exchanger at Re = 100. The best performance evaluation criteria of (PEC) at (8-ribs, and H = 5 mm) is 2.8 at Re = 750. The attached 45-helical ribs in the annulus path can generate kind of secondary flows, which enhance the fluid mixing operation between the hot surface of the annular gap and the cold fluid in the mid of the annulus, which lead to a high-temperature distribution. Increasing the height of 45°-helical ribs lead to an increase in the sur-face area subjecting to convective heat transfer.

Analysis of thermo-hydraulic and entropy generation characteristics for flow through ribbed-wavy channel

PurposeThe purpose of this study is to analyze the thermal, hydraulic and entropy generation characteristics for laminar flow of water through a ribbed-wavy channel with the top wall as wavy and bottom wall as flat with ribs of three different geometries, namely, triangular, rectangular and semi-circular.Design/methodology/approachThe finite element method-based numerical solver has been adopted to solve the governing transport equations.FindingsA critical value of Reynolds number (Recri) is found beyond which, the average Nusselt number for the wavy or ribbed-wavy channel is more than that for a parallel plate channel and the value of Recri decreases with the increase in a number of ribs and for any given number of ribs, it is minimum for rectangular ribs. The performance factor (PF) sharply decreases with Reynolds number (Re) up to Re = 50 for all types of ribbed-wavy channels. For Re > 50, the change in PF with Re is gradual and decreases for all the ribbed cases and for the sinusoidal channel, it increases beyond Re = 100. The magnitude of PF strongly depends on the shape and number of ribs and Re. The relative magnitude of total entropy generation for different ribbed channels varies with Re and the number of ribs.Practical implicationsThe findings of the present study are useful to design the economic heat exchanging devices.Originality/valueThe effects of shape and the number of ribs on the heat transfer performance and entropy generation have been investigated for the first time for the laminar flow regime. Also, the effects of shape and number of ribs on the flow and temperature fields and entropy generation have been investigated in detail.

Evaluation of risk factors for prognosticating blunt trauma chest.

&lt;b&gt;Introduction:&lt;/b&gt; Blunt trauma chest contributes to significant number of trauma admissions globally and is a cause of major morbidity and mortality. Many scoring systems and risk factors have been defined in past for prognosticating blunt trauma chest but, none is considered to be gold standard. &lt;/br&gt; &lt;b&gt;Aim:&lt;/b&gt; This study was conducted to reassess the significance of available scoring systems and others indicators of severity in prognosticating blunt trauma chest patients. &lt;/br&gt; &lt;b&gt;Materials and Methods:&lt;/b&gt; In this prospective observational study from November 2016 till March 2018, 50 patients with age more than 12 years with blunt chest trauma who required hospitalization were included. Nine risk factors were assessed namely- age of the patient, duration of presentation after trauma, number of ribs fractured, bilateral thoracic injury, evidence of lung contusion, associated extra thoracic injury, need for mechanical ventilation, Revised trauma Score (RTS) and Modified Early Warning Sign Score (MEWS). Severity of blunt thoracic trauma was assessed on following outcomes-SIRS, ARDS and Death. The inferences were drawn with the use of statistical software package SPSS v22.0. &lt;/br&gt; &lt;b&gt;Results:&lt;/b&gt; The age of 50 patients included in our study with a range of 15 to 76 years, the median age was 35.5 years. Statistically significant association was observed between occurrence of SIRS and multiple ribs fractured (p-value- 0.049), associated extra-thoracic injury (p-value-0.016) and higher MEWS score (p-value-0.025). ARDS occurrence was statistically significantly associated with all the risk factors except age.Death occurred more in patients with delayed duration of presentation to hospital (p-value &lt;0.001), multiple ribs fractured (p-value-0.001), bilateral thoracic injury(p-value&lt;0.001), associated extra-thoracic injury (p-value-0.004), patients who required ventilatory support (p-value&lt;0.001), low RTS (p-value-0.006) and high MEWS (p-value-0.005) on admission. This association was found statistically significant. &lt;/br&gt; &lt;b&gt;Conclusion:&lt;/b&gt; High MEWS, associated extra-thoracic injuries and multiple rib fractured can very well predict poor outcome in terms of SIRS, ARDS and death. Aggressive treatment protocols should be established for better outcome in these patients with blunt trauma chest.

Correlation of rib fracture patterns with abdominal solid organ injury: A retrospective observational cohort study

PurposeRib fractures are one of the most common causes of morbidity and mortality and are associated with abdominal solid organ injury (ASOI). The purpose of this study was to investigate the correlation of ASOI with the number, location, and involved segments of rib fracture(s) in blunt chest trauma. MethodsThis retrospective cohort study was conducted on patients with blunt chest trauma over the age of 15 years, who were hospitalized with the diagnosis of rib fractures from July 2015 to September 2020. After ethic committee approval, a retrospective chart review was designed and patients with a diagnosis of rib fractures were selected. Patients who had chest and abdominopelvic CT scan were included in the study and additional data including age, gender, injury severity score, trauma mechanism, number and sides of the fractured ribs (left/right/bilateral), rib fracture segments (upper, middle, lower zone) and results of chest and abdominal spiral CT scan were recorded. The correlation between ASOI and the sides, segments and number of rib fracture(s) was assessed by Pearson's correlation coefficient. ResultsAltogether 1056 patients with rib fracture(s) were included. The mean age was (42.76 ± 13.35) years and 85.4% were male. The most common mechanism of trauma was car accident (34.6%). Most fractures occurred in the middle rib zone (60.44%) and the most commonly involved ribs were the 6th and 7th ones (15.7% and 16.4%, respectively). Concurrent abdominal injuries were observed in 103 patients (34.91%) and were significantly associated with middle zone rib fractures. ConclusionThere is a significant relationship between middle zone rib fractures and ASOI. Intra-abdominal injuries are not restricted to fractures of the lower ribs and thus should always be kept in mind during management of blunt trauma patients with rib fractures.