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Earthquake catastrophes continue to cause substantial damage and casualties in many parts of the world. Despite design codes and standards having succeeded in reducing life losses during earthquakes, the level of damage in buildings after severe earthquakes still cannot be precisely predicted. Code provisions focus on the safety of buildings with no consideration of the amount of damage expected after an event. Current U.S. guidelines designate three performance levels related to the inelastic rotational demands of RC shear walls––immediate occupancy, life safety, and collapse prevention. The damage corresponding to these performance levels is minor, moderate, and severe, respectively. In the current study, these performance limits were implemented, along with other recognized standards, in order to design four RC ductile shear wall buildings with different heights located in a high seismic hazard zone. Each building was designed based on Canadian building codes to reach the three designated performance levels. For each case, the quantities of the constitutive materials of the RC shear walls were estimated and compared. The impact of the targeted performance level on the building's gravity-load-resisting system was also investigated. The cost effectiveness of using moderately ductile shear walls in high seismic hazard zones was also examined. [ABSTRACT FROM AUTHOR]

Despite the reduction in perioperative mortality observed over the past two decades, the risk of performing cardiac surgery in patients with coronary artery disease and severe left ventricular dysfunction remains high, these risks have led to the appearance of several ways to provide better outcomes. These ways are either mechanical like intraaortic balloon pump (IABP) or using medical inotropic drugs either adrenergic (epinephrine, norepinephrine &dobutamine) or non-adrenergic (levosimendan) drugs. It is indicated for the short-term treatment of acutely. Patients and Method:Patients had collected, evaluated thorough the preoperative, intra-operative, postoperative period withpoor left ventricular function ejection less than or equal to 40%. Cases had allocated into two gatherings of 50 cases.cases had admitted to the cardiovascular intensive care unit (ICU) 24h before surgery, a peri-operative dose of continuous levosimendan infusion over a total of 24h in the other gathering, cases will be submitted to conventional inotropes only (non levosimendan gathering) according to their medical requirements. Objective: the aim of this study had to detect the outcome of clinical use of preioperative Levosemindan for cases undergoing coronary artery bypass grafting with poor left ventricular function, also comparing it with the conventional medications as catecholamines. Results: Gathering A included 38 cases received levosimendan as perioperative cardiac support Gathering B included 40 cases received conventional cardiac support. A critical difference between both gatherings regarding total operative time, total bypass time, failure of weaning from cardiobypass (C.P.B), the use of intraoperative I.A.B.P. There had a statistically critical difference between both gatherings in which C.V. P had lower in levosimendan. There had statistically critical difference regarding base critical in the levosimendan gathering. with high statistical difference for medical support, no difference for support. Conclusion: the use of levosimendan perioperatively decrease the operative time, cross clamp time, facilitate the weaning from cardiomachine decrease the need of conventional inotropic support, decrease the duration of postoperative ventilation, improve the tissue perfusion, cardiac output parameters, length of I.C.U, hospital stay with decreasing early postoperative mortality, it had high degree of drug safety, tolerability. [ABSTRACT FROM AUTHOR]

Background: Cardiac tamponade after heart surgery is of great concern. It increases perioperative mortality and morbidity. Late tamponade might be easily missed and difficult to be diagnosed clinically. It is thought that posterior pericardial window decreases the incidence of postoperative tamponade. Aim of the work: The aim of the study to evaluate the prophylactic role of posterior pericardial window (PPW) in preventing pericardial tamponade after heart valve surgery. Methods: Our prospective randomized comparative study included 640 patients collected by simple random sampling. All patients were admitted in cardiothoracic surgery department-Zagazig University hospitals-Egypt, from January 2020 to May 2022. They were divided into PPW group and non-PPW group and each group contains 320 patients. Results: There is statistical significant difference as regrading occurrence of late tamponade between both groups and also less developed new onset atrial fibrillation in PPW group. Conclusions: Pericardial window is easily to be performed technically. We recommend that procedure to prevent late pericardial effusion and tamponade as it provides a good drainage pathway between pericardial and pleural cavities. We consider that technique is valuable for patients with coagulation disorders. [ABSTRACT FROM AUTHOR]

Background: Approximately 20 to 30 percent of patients experience Ischemic Mitral regurgitation after MI, with extreme IMR occurring in more than 10 percent of patients. Guidelines for appropriate surgical modality, whether for reconstruction or replacement, are still under review. Aim of the study: To compare the outcome of patients with Ischemic mitral regurgitation who underwent CABG with either mitral valve replacement or repair in 2 years follow up. Methods: The selected patients with ischemic mitral regurgitation underwent CABG and mitral valve replacement or repair at the cardiothoracic surgery department, zagazgig university during the period from July 2016 to June 2018 with postoperative follow up of 2 years. Results: we found no signifi cant difference between patients of group 1(Mitral v replacement) 22 patients and group 2 (Mitral v repair) 24 patients regarding preoperative, operative characteristic,operative data and early postoperative follow up with significant difference between the 2 groups regarding recurrence of (mitral regurgitation) MR in which 25% of the patients of repair group developed significant MR at the end of 2 years the follow up period Conclusions: The best surgical solution is problematic due to minimal scientific data. According to existing research, the role of MV replacement tends to be warranted in patients with extreme IMR. [ABSTRACT FROM AUTHOR]

Copyright of Zagazig Journal of Agricultural Research is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Management of traumatic hemothorax is an important problem in thoracic surgery. As an alternative to surgical treatment in patients who developed clotted hemothorax after trauma, intra-pleural fibrinolysis has been used with favorable results. This modality of treatment may reduce known morbidities secondary to surgical procedures and may result in significant medical cost savings. Aim of the study is to test the efficacy and safety of tissue plasminogen activator and Streptokinase for management of post traumatic clotted hemothorax. METHODS: our study included 40 patients presented with clotted hemothorax after chest trauma. Patients were divided into two groups each contains 20 patients. First group treated with intra-pleural Alteplase (tissue plasminogen activator) and the second group treated with streptokinase, both was instilled via an intercostal chest tube. Clinical and radiologic (chest radiographs (CXR) and chest computed tomography (CT) data used for evaluation of efficacy of both protocols. RESULTS: Alteplase give excellent results in clotted hemothorax, it showed dramatic improvement in both chest tube drain and pleural thickness without bleeding complications. Streptokinase protocol showed only improvement of chest tube drain. CONCLUSIONS: Intra pleural Alteplase is safe and more efficient than Streptokinase as a chemical modality in treating patients presented with post traumatic clotted hemothorax. [ABSTRACT FROM AUTHOR]

Background: Management of an early empyema is an important problem in thoracic surgery. As an alternative to surgical treatment empyema is in patients who developed early empyema, intra-pleural fibrinolysis has been used with favorable results. This modality of treatment may reduce known morbidities secondary to surgical procedures and may result in significant medical cost savings. Our study aim is to test the efficacy and safety of tissue plasminogen activator and Streptokinase for management of early empyema. Methods: Our study included 48 patients presented with complicated parapneumonic effusion and early empyema. Patients were divided into two groups each contains 24 patients. First group treated with intra-pleural Alteplase (tissue plasminogen activator) and the second group treated with streptokinase, both were instilled via an intercostal chest tube. Clinical and radiologic (chest radiographs (CXR) and chest computed tomography (CT) data used for evaluation of efficacy of both protocols. Results: Tissue plasminogen activator give excellent results in early empyema, it showed success rate 100%, dramatic improvement in both chest tube drain and pleural thickness with no need for further surgical intervention, Streptokinase showed success rate 83.4% in comparison to TPA. Conclusion: Intrapleural tissue plasminogen activator is safe and more efficient than Streptokinase as a chemical modality in treating patients presented with complicated pleural effusion and early empyema. [ABSTRACT FROM AUTHOR]

Seismic design codes predominantly assume that earthquakes involve a single ground shaking event; however, earthquakes can occur as a series of shocks. Consequently, the capacity of structures to resist earthquakes with multiple peaks without suffering severe damage is a crucial parameter. This research study evaluates the seismic performance of a high-rise building in Dubai using existing records of single and multiple peaks. Three-dimensional building model was developed considering the actual cross-sections of the horizontal and vertical elements fitting the seismic zone through dynamic response spectrum analysis. The building is analyzed using the nonlinear regime employing fast-nonlinear timehistory analysis with the scaled NS and EW records of the Niigata earthquake. The main finding of this work is that records with multiple peaks significantly increase structural response and magnify the structural damage compared with records of single-peak earthquakes; thus, earthquakes involving multiple shocks significantly increase the risk of structural failure in a building. [ABSTRACT FROM AUTHOR]

This paper investigates the impact of revised seismic hazard values in the National Building Code of Canada (NBCC 2015) on the design of reinforced-concrete (RC) shear wall buildings. Five buildings with different heights located in three cities in Canada are selected. Toronto, Montreal, and Vancouver are selected to represent low, medium, and high seismic hazard zones. The buildings are designed according to the NBCC 2010 and then checked against the updated design spectral accelerations of the NBCC 2015. The seismic demands are compared, and the need for retrofit of existing walls is evaluated. The analyses showed that the maximum interstory drift ratios increased specially for buildings in Vancouver. The shear force and bending moment demands increased for most buildings in Vancouver by up to 32% and 60%, respectively. A significant decline in the moment overstrength ratio was noticed for walls in Vancouver, which indicates that flexural strengthening might be mandatory for these walls. Moreover, the code changes had a great negative impact on the walls' ductility for buildings in Vancouver due to the higher deformations exhibited. Several retrofit techniques available in the literature were discussed to enhance the flexural strength and ductility of RC shear walls as remedies for the consequences of the updated seismic hazard in Canada. [ABSTRACT FROM AUTHOR]

This study aims at the investigation of GNSS-PP method to determine the dynamic characteristics of structures. Cantilever steel bars having lengths of 70, 100 and 120 cm were tested under dynamic excitation. The GNSS was used to measure the natural frequencies and damping values of all the tested cantilever structures. The GNSS data were processed using relative GNSS positioning and PPP methods. The results obtained using these two methods were also compared with the dynamic characteristics obtained by applying the theoretical and finite element (FE) methods. Furthermore, it is investigated the impact of the stable data length before oscillation events on kinematic PPP. The study showed that the maximum difference among the experimental results in terms of natural frequencies proceeded using PPP is 0.08 Hz when compared with the theoretical and FE results. Furthermore, there is no difference between the PPP and relative GNSS positioning in determining the dynamic behaviour of structures eventhough roving GNSS antenna remains motionless for short-time, such as a few-minutes, before an event occurred. [ABSTRACT FROM AUTHOR]

The number of bridges in South Korea has almost tripled in the past few decades. Monitoring the structural behavior of these bridges is essential to maintain their performance in the infrastructure network and keep them in the best possible condition. The study presented in this paper aims to evaluate the Tun Bridge, located in Seoul, Korea. The bridge was tested under static and dynamic loads following the American Association of State Highway and Transportation Officials (AASHTO) standards. Twenty load cases and a wide range of truck speeds were applied during the bridge test. The bridge responses were captured using a short-period structural health monitoring system. Statistical analysis and signal processing for all the measurements were used to assess the structural behavior and fatigue life of the bridge. Bridge deformation/deflection and fatigue responses were evaluated. Furthermore, comparison with the available data from previous tests on the same bridge (17 years earlier) showed that the changes in static deflection and dynamic frequency were 13.87% and 2.73%, respectively. In addition, deflection and fatigue responses were found to be negligible under static and dynamic loads. Therefore, it was concluded that the bridge's behavior during its operational state was shown to be safe. [ABSTRACT FROM AUTHOR]

This study was aimed at evaluating the effect of E-glass fibers (≈ 1.0 mm long, ø = 0. 0 1 7 mm with 1.0 wt.% and 5.0 wt.%) in two (MegacemTM and GlassFillTM) glass-ionomer cements (GIC) to enhance their mechanical properties. The six specimen groups were assigned to MCC, MC1, MC5, GFC, GF1 and GF5, and evaluated after 24 h dry storage and 30 days water storage. The results showed considerable increase in surface roughness and the flexural strength values of both cements in both time intervals, whereas a statistically higher elastic modulus was observed in MC1 24 h (15.3 GPa) and 30 days groups (7.1 GPa). On the contrary, no steady improvement in nano-hardness and yield strength were observed with the addition of chopped glass fibers. The SEM images suggest inadequate adhesion of the fibers to GIC matrix. Reinforcing GICs with short chopped E-glass fibers may not improve all the mechanical properties of GIC. [ABSTRACT FROM AUTHOR]

The clinical success of ceramic restorations is affected by the ceramic bonding procedure. The objective of the study was to evaluate the effect of different surface treatments, including the use of self-etching ceramic primer (SECP), on resin cement-glass ceramic bond strength. Thirty lithium disilicate ceramic (LDC) rectangles (3 mm × 3 mm × 8 mm) were fabricated Specimens were randomly assigned into three experimental groups (n = 10) according to the surface treatment: Group 1-hydrofluoric acid [HF acid]+ silane + universal adhesive; Group 2-HF + universal adhesive; Group 3-SECP + universal adhesive. All specimens were stored in distilled water for 24 h at 37 °C and shear bond strength (SBS) was tested at a crosshead speed of 0.5 mm (Universal Testing machine-Instron). Failure modes were evaluated using a digital microscope for all specimens. Analysis of variance and the Tukeypost hoctests using SPSS (Version 22.0, IBM, New York, USA) were used to analyze data. The SBS of groups 1 (19.74 ± 1.28 MPa) and 3 (21.11 ± 2.07 MPa) were significant higher than group 2 (14.80 ± 1.94 MPa). The SBS values for specimens in groups 1 (19.74 ± 1.28 MPa) and 3 (21.11 ± 2.07 MPa) were comparable. Adhesive, mixed and cohesive failure modes were observed and mixed failure was the most common in all groups. Therefore, the use of SECP and universal adhesive is recommended as an alternative to the use of HF acid in combination with ceramic primer while bonding to LDC. [ABSTRACT FROM AUTHOR]

BACKGROUND: Adhesive resin composite, which is used to bond orthodontic bracket to tooth surface is exposed to the influence of wear by tooth brushing and wear may influence loosening of the bracket. OBJECTIVE: The aim of this study was to evaluate in vitro the effect of tooth brushing on the adhesion strength of orthodontic brackets bonded to surface treated porcelain. METHOD: A total of 90 glazed porcelain fused to metal facets (PFM) were randomly assigned into 3 groups according to the surface treatment to be received. Group 1 was conditioned with hydrofluoric acid (HF), group 2 conditioned with grit-blasting (GB) and group 3 conditioned with tribochemical silica coating (RC). The groups were evaluated for surface roughness (Ra) before and after surface treatment. Next, 15 samples from each group were subjected to brushing and remaining 15 samples served as the baseline (n = 15). Adhesion strength (shear bond strength)was recorded using a universal testing machine. Data collected were analyzed by ANOVA and Tukey's multiple comparison post hoc analysis. RESULTS: Tooth brushing decreased the bond strength in all groups. The highest adhesion strength (baseline and after brushing) was observed in group 3 (26.8 ± 1.77 MPa and 23.57 ± 1.02 MPa) and the lowest was found in group 1 (9.6 ± 1.5 MPa and 5.87 ± 0.77 MPa). Group 3 specimens exhibited the highest Ra (1.24 ± 0.08). CONCLUSION: It was found that tooth brushing of the exposed adhesive resin composite at the bracket-bonding substrate interface lowers the bonding strength regardless of the surface treatment of the substrate. [ABSTRACT FROM AUTHOR]

Objective: Aneurysms in Behcet's disease are rare, serious, and recurrent. To achieve durable treatment, patients should receive immunosuppressive therapy before intervention to induce remission. We present early and long-term results of emergency cases of active Behcet's disease, which did not permit waiting for suppressive treatment.Patients and Methods: The study was undertaken on all cases admitted to the vascular unit, King Fahd Hospital of University for aneurysm treatment in patients with active Behcet's disease over about 10 years. All patients had exclusion of the aneurysm either by open surgery or endovascular intervention. Morbidities and mortality were recorded within the hospital admission and on the follow-up.Results: During the study period, three cases were included. All interventions were successful and lifesaving. However, two cases, treated with surgical interposition grafts, were blocked in the intermediate term follow-up (2-12 months) and one case, treated with endovascular treatment, complicated with pseudoaneurysm at femoral puncture site after six months.Conclusion: Although early results were good, intermediate ones were not satisfactory because of progressive graft thrombosis and formation of new aneurysms. Awareness of these rare cases help for early identification and proper immunosuppressive before emergency vascular intervention is warranted. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Most surgeons make their decision to amputate or perform limb salvage of a mangled extremity based on scoring systems and grading of acute ischemic limb. We report on a child in whom limb salvage was achieved in spite of a clinical picture of irreversible ischemia with high mangled severity scores. Attempts to revascularize the mangled extremity of children are recommended, regardless of their severity scores and condition of the foot. [ABSTRACT FROM AUTHOR]

Objective. Diminished wound healing is a common problem in diabetic patients due to diminished angiogenesis. SHMSP was found to promote angiogenesis. The present study was carried out to examine the effect of this peptide in healing of wounds in diabetic rabbits. Materials and Methods. Twenty male New Zealand rabbits were used in this study. Diabetes mellitus was induced and the rabbits were randomly divided into two equal groups: control group and peptide group. A-full thickness punch biopsy was made to create a wound of about 10mm on the right ears of all rabbits. Every day, the wound was cleaned with saline in control groups. In the peptide group, 15mg of SHMSP was applied after cleaning. On day 15th, all animals were sacrificed, and the wounds were excised with a rim of 5mm of normal surrounding tissue. Histo-pathological assessment of wound healing, inflammatory cell infiltration, blood vessel proliferation, and collagen deposition was performed. Results. There were no deaths among the groups. There was significant increase in wound healing, blood vessel proliferation and collagen deposition, and significant decrease in inflammatory cell infiltration in the peptide group compared to the control group. Conclusion. Topical application of SHMSP improves wound healing in diabetic rabbits. [ABSTRACT FROM AUTHOR]

Many hemodynamic factors have been shown to be associated with increased intimal hyperplasia at the distal anastomosis of arterial bypass graft. However, the relationship between the length of anastomosis and the development of such a complication has not been studied before. The aim of this study was to assess this relationship at the distal anastomosis with a Dacron graft. Iliofemoral bypass using 6 mm Dacron grafts was performed in 10 German shepherd dogs. In accordance with preoperative randomization to individual animal legs, distal anastomoses were reconstructed using four different groups (A, B, C, and D), depending on the length of the arteriotomy: 3.0, 3.5, 4.0, and 4.5 times the internal diameter of the artery, respectively. The vessels were harvested 6 months after the operation, and specimens were processed for histologic and transmission electron microscopic (TEM) studies. Quantitative analysis was performed to assess the extent of intimal hyperplasia at three zones (heel, toe, and midzone of the arterial bed) of the distal anastomosis. Sixteen arterial bypasses were included in this study. Both light and TEM studies revealed evidence of intimal hyperplasia in the four groups. Quantitative analysis showed a significant decrease in intimal hyperplasia with increasing the length of the anastomosis at the heel, toe, or midzone of the arterial bed. Mean (mum +/- SD) intimal hyperplasia of the three zones together was significantly higher in group A than group B (585 +/- 106 vs 423 +/- 8.6, p < .001) and in group B than group C (423 +/- 8.6 vs 202 +/- 15, p < .001). However, the difference between group C and group D (202 +/- 15 vs 162 +/- 8.6; p = .13) was statistically insignificant. The present study showed that the length of the anastomosis is one of the hemodynamic factors involved in the development of intimal hyperplasia. Anastomotic techniques that resulted in the least intimal hyperplasia were end to side, with length 4 or 4.5 times the internal diameter of the artery. [ABSTRACT FROM AUTHOR]

The Vascular Unit at Suez Canal University Hospital in Egypt covers a wide area with high rates of severe injuries. This is a prospective study of mangled extremities to identify risk factors associated with limb loss in these patients. Between December 2000 and August 2003, a prospective study on all patients with arterial injuries in mangled extremities was undertaken. All patients were scored using the Mangled Extremity Severity Score (MESS) and the Mangled Extremity Severity Index (MESI). During this period, arterial reconstruction was performed in 62 patients. Primary patency, secondary patency, and limb salvage rates were 81%, 85.5%, and 93.5%, respectively. The only factor affecting limb salvage (statistical trend) was the site of trauma (upper limb 100% vs lower limb 89%; p = .08%). There was no significant effect related to the mechanism of trauma (blunt 90% vs stab 100%; p = .125), MESS (< 7, 100% vs > 7, 91%; p = .22), and MESI (< 20, 100% vs > 20, 90.5%; p = .154). Upper limb injuries were the least likely to lead to amputation. We recommend that all injuries, whatever their score, should be surgically explored before treatment decisions are made. [ABSTRACT FROM AUTHOR]

Handlebar hernias are abdominal wall hernias resulting from direct trauma to the anterior abdominal wall. They usually result at weak anatomic locations of the abdominal wall. Such traumatic hernias are rare, requiring a high index of suspicion for a clinical diagnosis. We report the case of a handlebar hernia resulting from an injury sustained during a vehicular injury, and discuss the management of such injuries. [ABSTRACT FROM AUTHOR]

The aim of this study is to compare the creep/recovery behavior of bulk-fill dental composites after storage in various food simulating organic solvents. For this purpose, five different resin-composites (four bulk-fills and one conventional) were used. A total of 20 rectangular specimens (14 mm × 3 mm × 0.7 mm) were prepared by filling the resin-composites in Teflon mold. All of the specimens for each material (n = 5) were divided into four groups namely dry (control), distilled water (DW), artificial saliva, and absolute ethanol. The specimens were subjected to three-point bending creep test during immersion directly. A constant load of 2 N was used for each specimen with loading and unloading time 2 h each. Results: SF2 and XF showed a lower creep strain % after immersion, ranging from 0.44 (dry) to 0.75 (saliva) and 0.43 (dry) to 0.80 (ethanol), respectively. TNC BF depicts the maximum creep strain % ranging from 1.24% (dry) to 2.87% (ethanol) followed by FBF ranging from 1.17 (dry) to 2.59 (ethanol). However, the conventional material (GR) showed lower creep strain after immersion ranging from 0.28 to 0.54. Moreover, SF2 resulted in the highest creep recovery in all of the composites groups, as well as conventional material. The other composite groups showed lower creep recovery as compared to the conventional material (GR). The creep strain % for all the bulk-fill composites materials were increased during immersion in the liquids. However, for the conventional material, the creep deformation is decreased after immersion. SF2 showed the highest percentage of creep recovery among the bulk-fill composites, followed by XF. [ABSTRACT FROM AUTHOR]