Strain localization and failure load predictions of geosynthetic reinforced soil structures

Alsaleh, Mustafa,Kitsabunnarat, Akadet,Helwany, Sam Techno-Press 2009 Interaction and multiscale mechanics Vol.2 No.3

This study illustrates the differences between the elasto-plastic cap model and Lade's model with Cosserat rotation through the analyses of two large-scale geosynthetic-reinforced soil (GRS) retaining wall tests that were brought to failure using a monotonically increasing surcharge pressure. The finite element analyses with Lade's model were able to reasonably simulate the large-scale plane strain laboratory tests. On average, the finite element analyses gave reasonably good agreement with the experimental results in terms of global performances and shear band occurrences. In contrast, the cap model was not able to simulate the development of shear banding in the tests. In both test simulations the cap model predicted failure loads that were substantially less than the measured ones.

Combining GPS and accelerometers’ records to capture torsional response of cylindrical tower

Raed J. AlSaleh,Clemente Fuggini 국제구조공학회 2020 Smart Structures and Systems, An International Jou Vol.25 No.1

Researchers up to date have introduced several Structural Health Monitoring (SHM) techniques with varying advantages and drawbacks for each. Satellite positioning systems (GPS, GLONASS and GALILEO) based techniques proved to be promising, especially for high natural period structures. Particularly, the GPS has proved sufficient performance and reasonable accuracy in tracking real time dynamic displacements of flexible structures independent of atmospheric conditions, temperature variations and visibility of the monitored object. Tall structures are particularly sensitive to oscillations produced by different sources of dynamic actions; such as typhoons. Wind forces induce in the structure both longitudinal and perpendicular displacements with respect to the wind direction, resulting in torsional effects, which are usually more complex to be detected. To efficiently track the horizontal rotations of the in-plane sections of such flexible structures, two main issues have to be considered: a suitable sensor topology (i.e., location, installation, and combination of sensors), and the methodology used to process the data recorded by sensors. This paper reports the contributions of the measurements recorded from dual frequency GPS receivers and uni-axial accelerometers in a full-scale experimental campaign. The Canton tower in Guangzhou-China is the case study of this research, which is instrumented with a long-term structural health monitoring system deploying both accelerometers and GPS receivers. The elaboration of combining the obtained rather long records provided by these two types of sensors in detecting the torsional behavior of the tower under ambient vibration condition and during strong wind events is discussed in this paper. Results confirmed the reliability of GPS receivers in obtaining the dynamic characteristics of the system, and its ability to capture the torsional response of the tower when used alone or when they are combined with accelerometers integrated data.

Frequency, Clinical Pattern and Outcome of Thrombosis in Cancer Patients in Saudi Arabia

Aleem, Aamer,Diab, Abdul Rahman Al,Alsaleh, Khalid,Algahtani, Farjah,Alsaeed, Eyad,Iqbal, Zafar,El-Sherkawy, Mohamed Sherif Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.4

Objectives: Thrombotic risk is increased in patients with cancer and there are important implications for those who suffer a venous thromboembolism (VTE). We undertook this study to determine the frequency, clinical patterns, and outcome of VTE in Saudi patients with cancer. Methods: Cancer (solid tumors and lymphoma) patients who developed VTE from January 2004 to January 2009 were studied retrospectively. Demographics and clinical characteristics related to thrombosis and cancer were evaluated. Results: A total of 701 patients with cancer were seen during the study period. VTE was diagnosed in 47 (6.7%) patients (median age 52, range 18-80 years). Lower limb DVT was the most common type, seen in 47% patients, followed by PE in 19%, and 19% patients had both DVT & PE. Thrombosis was symptomatic in 72% patients while it was an incidental finding on routine workup in 28%. Cancer and VTE were diagnosed at the same time in 38% of patients, and 47% patients developed VTE during the course of disease after the cancer diagnosis. The majority of VTE post cancer diagnoses occurred during the first year (median 4 months, range 1-14). Additional risk factors for VTE were present in 22 (47%) patients and 14 (30%) of these patients were receiving chemotherapy at the time of thrombosis. Only 5 (10.6%) patients were receiving thrombo-prophylaxis at the time of VTE diagnosis. Most common types of tumors associated with thrombosis were breast cancer, non-Hodgkin's lymphoma and lung cancer. The majority of the affected patients (79%) had advanced stage of cancer. After a median follow-up of 13 (range 0.5-60) months, 38 (81%) patients had died. There was no difference in the mortality of patients with symptomatic or asymptomatic thrombosis (82% vs 78.6%). Conclusions: Thrombotic complications can develop in a significant number of patients with cancer, and almost half of the patients have additional risk factors for VTE. Thrombosis is usually associated with advanced disease and can be asymptomatic in more than a quarter of cases. Thromboprophylaxis in cancer patients is under-utilized. Community based studies are needed to accurately define the extent of this problem and to develop effective prophylactic strategies.

Clofarabine in the Treatment of Elderly Patients with Acute Myeloid Leukemia

Aleem, Aamer,Anjum, Farhan,Algahtani, Farjah,Iqbal, Zafar,Alsaleh, Khalid,AlMomen, Abdulkareem Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.2

Background: Elderly patients with acute myeloid leukemia (AML) have a poor outcome because of co-morbidities, poor tolerance to intensive chemotherapy and inherently more resistant disease. Clofarabine is a second generation nucleoside analogue which has shown promising activity in elderly patients with AML. This study was conducted to review the outcome of treatment with clofarabine in a group of such patients. Methods: The records of 5 elderly patients who were diagnosed to have AML and treated with clofarabine over a 12 month period were reviewed retrospectively. Results: There were 2 female and 3 male patients with a median age of 68 years (range 65-82). At the time of treatment, 2 patients had newly diagnosed AML not considered suitable for intensive therapy, while 3 patients had partial or no response to conventional chemotherapy. The overall response rate was 100%, all patients achieving a complete remission. Induction and consolidation were well tolerated. All patients developed neutropenia with a median duration of 20 days (range 17-42). One patient developed hand and foot syndrome and a generalized rash but recovered. There was no mortality and all patients remained in remission after a median follow-up of 5.2 months (Range 3-10). Conclusion: Clofarabine (alone or in combination) is active in elderly AML patients with an acceptable safety profile and should be considered a potential option in this group.

Correlation of Preoperative Ki67 and Serum CA15.3 Levels with Outcome in Early Breast Cancers - a Multi Institutional Study

Rasmy, A,Abozeed, W,Elsamany, S,El Baiomy, M,Nashwa, A,Amrallah, A,Hasaan, E,Alzahrani, A,Faris, M,Alsaleh, K,AlFaraj, A Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.7

Background: To investigate the association between preoperative pathological Ki-67 labeling index and serum tumor marker cancer antigen 15-3 (CA 15-3) with clinic-pathological parameters and treatment outcomes in early breast cancer. Materials and Methods: A retrospective study at 4 cancer centers in Saudi Arabia and Egypt was performed. Data were collected for female patients diagnosed with unilateral early breast cancer between March 2010 and October 2013. Cases treated with neoadjuvant chemotherapy (NACT) followed by surgery and radiotherapy were included. NACT included 6-8 cycles of anthracycline and taxane based regimens. Trastuzumab and hormonal treatments were added according to HER2 and hormone receptor status. Baseline serum CA15.3 and pathological Ki67 levels were evaluated and correlated with disease free survival (DFS) and overall survival (OS). Results: A total of 280 pts was included. The median age was 49 years (38-66 y) and median overall survival was 35 (20-38) months (mo). Estrogen receptors (ER), progesterone receptors (PR) and HER 2 receptors were positive in 233 (83.2%), 198 (70%) and 65 cases (23.2%), respectively. High preoperative Ki67 and CA15.3 were noted in 177 (63.2%) and 131 (46.8%). A total of 45 (16%) patients had distal or local recurrence and 24 (8.6%) died of their disease. Most of the relapsed cases had high preoperative Ki-67 (n=41, 91%) and CA15.3 (n=28, 62%) values. All of the patients who died had a high Ki-67 but CA15.3 was high in 9 (37%) only. Mean DFS/OS in patients with high preoperative Ki-67 was 32 months /32 months as compared to 37 months/35 months in those with normal Ki-67 (p<0.001). Correlation of preoperative CA15.3 and survival was statistically not significant. Conclusions:Preoperative Ki-67 can be a predictive and prognostic marker. Higher levels are associated with poor DFS and OS in patients with early BC.