• Advances in nano research
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• v.10 no.4
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• pp.385-395
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• 2021

This research concentrates on the effects of distributions and volume fractions of carbon nanotubes (CNT) on the nonlinear bending behavior of deep cylindrical panels reinforced by functionally graded carbon nanotubes under thermo-mechanical loading, hitherto not reported in the literature. Assuming the effects of shear deformation and moderately high value of the radius-to-side ratio (R/a), based on the first-order shear deformation theory (FSDT) and von Karman type of geometric nonlinearity, the governing system of equations is obtained. The analytical solution of field equations is carried out using the Ritz method together with the Newton-Raphson iterative scheme. The effects of radius-to-side ratio, temperature change, and boundary conditions on the nonlinear response of the functionally graded carbon nanotubes reinforced composite deep cylindrical panel (FG-CNTRC) are investigated. It is concluded that, among the five possible distribution patterns of CNT, FG-V CNTRC deep cylindrical panel is strongest with the highest bending moment and followed by UD, X, O, and Ʌ-ones. Also, considering the present deep cylindrical panel formulation increases the accuracy of the results. Hence, according to the noticeable amount of R/a in FG-CNTRC cylindrical panels, it is mandatory to apply strain-displacement relations of deep cylindrical panels for bending analysis of FG-CNTRC which certainly is desirable for industrial application.

• Journal of Trauma and Injury
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• v.35 no.2
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• pp.118-122
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• 2022

The usual cause of penetrating thoracoabdominal injuries with evisceration are stab wounds with knives and other sharp weapons used during fights and conflicts. Evisceration of the abdominal viscera as a result of trauma, with its attendant morbidity and mortality, requires early intervention. Gunshot wounds can also cause penetrating thoracoabdominal injuries. We report the case of a 52-year-old male patient, a worker at a timber-processing factory, who was assaulted with a chainsaw by his colleague following a disagreement. He was seen at the accident and emergency department of Olabisi Onabanjo University Teaching Hospital, Sagamu, Nigeria with a thoracoabdominal injury about 1.5 hours after the attack. He had a left thoracoabdominal laceration with abdominal evisceration and an open left pneumothorax. He was managed operatively, made a full recovery, and was discharged 16 days after admission. He was readmitted 4 months after the initial surgery with acute intestinal obstruction secondary to adhesions. He underwent exploratory laparotomy and adhesiolysis. He made an uneventful recovery and was discharged on the 9th postoperative day for subsequent follow-up.

• Structural Engineering and Mechanics
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• v.85 no.4
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• pp.445-459
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• 2023

The current investigation is the first endeavor to apply the full layerwise finite element method (FEM) in free vibration analysis of functionally graded (FG) composite plates reinforced with graphene nanoplatelets (GPLs) in thermal environment. Unlike the equivalent single-layer (ESL) theories, the layerwise FEM focuses on all three-dimensional (3D) effects. The GPLs weight fraction is presumed invariable in each layer but varies through the plate thickness in a layerwise model. The modified Halpin-Tsai model is employed to acquire the effective Young's modulus. The rule of mixtures is applied to specify the effective Poisson's ratio and mass density. First, the current method is validated by comparing the numerical results with those stated in the available works. Next, a thorough numerical study is performed to examine the influence of various factors involving the pattern of distribution, weight fraction, geometry, and size of GPLs, together with the thickness-to-span ratio, thermal environment, and boundary conditions of the plate, on its free vibration behaviors. Numerical results demonstrate that employing a small percentage of GPL as reinforcement considerably grows the natural frequencies of the pure epoxy. Also, distributing more square-shaped GPLs, involving a smaller amount of graphene layers, and vicinity to the upper and lower surfaces make it the most efficient method to enhance the free vibration behaviors of the plate.

• Journal of Microbiology and Biotechnology
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• v.34 no.2
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• pp.349-357
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• 2024

Foodborne pathogens, like Listeria monocytogenes, continue to inflict substantial financial losses on the food industry. Various methods for detecting Listeria in food have been developed and numerous studies have been conducted to compare the different methods. But, in recent years, new Listeria species have been identified, and currently the genus comprises 26 species. Therefore, it would be a more accurate approach to re-evaluate existing detection methods by considering new species. The present investigation involved the analysis of 42 ready-to-eat (RTE) foods, encompassing a variety of food categories, such as mezes, salads, dairy products, and meat products, with the aim of ascertaining the presence of Listeria. Among the traditional culture-dependent reference methods, the ISO 11290 method was preferred. The process of strain identification was conducted with the API Identification System. Furthermore, to ascertain the existence of L. monocytogenes and Listeria spp., the samples underwent additional analysis employing the VIDAS Immunoassay System, ELISA, and RT-PCR methodologies. Thus, four alternative approaches were employed in this study to compare not only the different methods used to determine Listeria while taking into account the newly identified Listeria species, but also to assess the compliance of retail RTE food items with microbiological criteria pertaining to the genus Listeria. Based on the conducted analyses, L. monocytogenes was conclusively determined to be present in one sample. The presence of Listeria spp. was detected in 30.9% of the samples, specifically in Turkish cig kofte, sliced salami, and salads.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.21 no.3
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• pp.176-183
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• 2018

Purpose: Acute gastroenteritis (AGE) is a major cause of morbidity and remains a major cause of hospitalization. Following the Syrian refugee crisis and insufficient clean water in the region, this study reviews the etiological and epidemiological data in Lebanon. Methods: We prospectively analyzed demographic, clinical and routine laboratory data of 198 children from the age of 1 month to 10 years old who were admitted with the diagnosis of AGE to a private tertiary care hospital located in the district of Nabatieh in south Lebanon. Results: Males had a higher incidence of AGE (57.1%). Pathogens were detected in 57.6% (n=114) of admitted patients, among them single pathogens were found in 51.0% (n=101) of cases that consisted of: Entamoeba histolytica 26.3% (n=52), rotavirus 18.7% (n=37), adenovirus 6.1% (n=12) and mixed co-pathogens found in 6.6% (n=13). Breast-fed children were significantly less prone to rotavirus (p=0.041). Moreover, children who had received the rotavirus vaccine were significantly less prone to rotavirus (p=0.032). Conclusion: Our findings highlight the high prevalence of E. histolytica infection as the major cause of pediatric gastroenteritis in hospitalized children, during the summer period likely reflecting the insanitary water supplies and lack of hygiene. Moreover the 42.4% of unidentified causative pathogens should prompt us to widen our diagnostic laboratory arsenal by adopting new diagnostic technologies.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.24 no.4
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• pp.346-356
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• 2021

Purpose: Campylobacter species are currently the most common cause of bacterial gastroenteritis. In Lebanon, Campylobacter infection occurrence is underdiagnosed owing to the lack of specific culture and rapid test kits, particularly among children. This study aimed to evaluate the prevalence, laboratory findings, and clinical characteristics of Campylobacter infection in hospitalized children with acute gastroenteritis in South Lebanon. Methods: We conducted a 6-month retrospective cohort study between January and June 2018, including 291 children aged between 1 month and 12 years, who were admitted to a tertiary healthcare center in South Lebanon. The medical files of the patients were reviewed to retrieve the required clinical information, including clinical and laboratory data. Results: The prevalence of campylobacteriosis agents in pediatric patients with acute gastroenteritis is 12.02%. Patients infected with Campylobacter had more severe acute gastroenteritis than Campylobacter-negative patients and often presented with high-grade fever, diarrhea episodes more than six times per day, diarrhea lasting for more than five days, and dehydration. Indeed, children with high-grade fever (≥38.5℃) were five times more likely to test positive for Campylobacter than those with low-grade fever. In addition, the results showed a higher Vesikari score for the majority of Campylobacter-positive patients with severe acute gastroenteritis compared to a moderate profile for Campylobacter-negative patients. Conclusion: The present study findings highlight that Campylobacter infection is frequent among children with acute gastroenteritis. Therefore, the detection of Campylobacter should be carried out for the diagnosis of human gastroenteritis in Lebanon, along with the detection of routine enteropathogens.

• Journal of Pharmacopuncture
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• v.25 no.3
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• pp.209-215
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• 2022

Objectives: Aqueous leaf extract of Tridax procumbens (ALETP) has potent relaxant activity. However, this relaxant activity in respiratory smooth muscle remains uninvestigated. This study investigates the effect of ALETP on the contractile activity of tracheal smooth muscle (TSM) in adult male Wistar rats. Methods: Twelve male Wistar rats divided into 2 groups and were treated with either 100 mg/kg of ALETP (ALETP treatment group) or vehicle (distilled water; control group) through oral gavage for 4 weeks. Dose responses of TSM from the 2 groups to acetylcholine (10^-9 to 10^-5 M), phenylephrine (10^-9 to 10^-5 M), and potassium chloride (KCl; 10^-9 to 10^-4 M) were determined cumulatively. Furthermore, cumulative dose responses to acetylcholine (10^-9 to 10^-5 M) after pre-incubation of TSM with atropine (10^-5 M), L-NAME (10^-4 M), indomethacin (10^-4 M), and nifedipine (10^-4 M), were determined. Results: Treatment with ALETP substantially inhibited TSM contraction stimulated by cumulative doses of acetylcholine, phenylephrine, and KCl. Furthermore, preincubation of TSM from the 2 groups in atropine significantly inhibited contractility in TSM. Incubation in L-NAME and indomethacin also significantly inhibited contractility in TSM of ALETP-treated rats compared to that of controls. Contractile activity of the TSM was also inhibited significantly with incubation in nifedipine in ALETP-treated rats. Conclusion: ALETP enhanced relaxant activity in rat TSM primarily by blocking the L-type calcium channel and promoting endothelial nitric oxide release. ALETP contains agents that may be useful in disorders of the respiratory tract.

• Steel and Composite Structures
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• v.44 no.4
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• pp.451-471
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• 2022

In the present paper, the static bending and buckling responses of functionally graded carbon nanotubes-reinforced composite (FG-CNTRC) beam under various boundary conditions are investigated within the framework of higher shear deformation theory. The significant feature of the proposed theory is that it provides an accurate parabolic distribution of transverse shear stress through the thickness satisfying the traction-free boundary conditions needless of any shear correction factor. Uniform (UD) and four graded distributions of CNTs which are FG-O, FG-X, FG- and FG-V are selected here for the analysis. The effective material properties of FG-CNTRC beams are estimated according to the rule of mixture. To model the FG-CNTRC beam realistically, an efficient Hermite-Lagrangian finite element formulation is successfully developed. The accuracy and efficiency of the present model are demonstrated by comparison with published benchmark results. Moreover, comprehensive numerical results are presented and discussed in detail to investigate the effects of CNTs volume fraction, distribution patterns of CNTs, boundary conditions, and length-to-thickness ratio on the bending and buckling responses of FG-CNTRC beam. Several new referential results are also reported for the first time which will serve as a benchmark for future studies in a similar direction. It is concluded that the FG-X-CNTRC beam is the strongest beam that carries the lowest central deflection and is followed by the UD, V, Λ, and FG-O-CNTRC beam. Besides, the critical buckling load belonging to the FG-X-CNTRC beam is the highest, followed by UD and FG-O.

• Maritime Security
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• v.8 no.1
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• pp.1-39
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• 2024

This study started with the awareness that domestic studies on China's maritime gray zone strategy have been following the analysis results of previous studies, and that only principled positions and directions for countermeasures remain at the 'declarative and conceptual' level. In order to overcome the above problems, the author analyzed the maritime gray zone strategy being developed in the South China Sea, East China Sea, and the West Sea and Ieodo areas, recognizing that China is developing a maritime gray area strategy based on the 'three warfare' that constitutes its own strategic culture. As a result of the analysis, it is predicted that China's maritime gray zone strategy will be more aggressive in order to occupy the West Sea and Ieodo in the future. As a concept of our naval response strategy, The author proposed to 'neutralize' the development effect of 'three warfare', the basis of China's maritime gray zone strategy, to stop the gradual change in the phenomenon induced by China, and to continuously pursue 'return' to a maritime order based on norms and rules. In this study, a 'concrete and systemized' countermeasure to implement this was presented.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.2
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• pp.451-457
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• 2012

One decade early onset of the breast cancer in Iranian females was reported but the basis of the observed difference has remained unclear and difference in gene silencing by epigenetic processes is suggested. Hence, this study was sought to map the methylation status of estrogen receptor (ER) gene CpG islands and its impact on clinicopathological factors of triple negative and non-triple negative ductal cell carcinoma of the breast in Iranian females. Surgically resected formalin-fixed paraffin-embedded breast tissues from sixty Iranian women with confirmed invasive ductal carcinoma were assessed by methylation-specific PCR using primer sets encompassing some of the 29 CpGs across the ER gene CpG island. The estrogen and progesterone receptors, Her-$2^+$ overexpression, and nuclear accumulation of P53 were examined using immunohistochemistry (IHC). Methylated ER3, ER4, and ER5 were found in 41.7, 11.3, and 43.3% of the samples, respectively. Significantly higher methylation of ER4 was found in the tumors with nuclear accumulation of P53, and significantly higher methylation of ER5 was found in patients with lymph node involvement and tumor with bigger size or higher grades. Furthermore, significantly higher rate of ER5 methylation was found in patients with Her-$2^+$ tumors and in postmenopausal patients with $ER^-$, $PgR^-$, or $ER^-/PgR^-$ tumors. However, no significant difference in ERs methylation status was found between triple negative and non-triple negative tumors in pre- and postmenopausal patients. Findings revealed that aberrant hypermethylation of the ER-alpha gene frequently occurs in Iranian women with invasive ductal cell carcinoma of the breast. However, methylation of different CpG islands produced a diverse impact on the prognosis of breast cancer, and ER5 was found to be the most frequently methylated region in the Iranian women, and could serve as a marker of poor prognosis.