Search results for: concrete grade

Authors: Amin Kamal Akhnoukh, Lois Zaki Kamel, Magued Mourad Barsoum

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The objective of this research is to mitigate and prevent the alkali silica reactivity (ASR) in highway construction projects. ASR is a deleterious reaction initiated when the silica content of the aggregate reacts with alkali hydroxides in cement in the presence of relatively high moisture content. The ASR results in the formation of an expansive white colored gel-like material which forms the destructive tensile stresses inside hardened concrete. In this research, different types of local aggregates available in the State of Arkansas were mixed and mortar bars were poured according to the ASTM specifications. Mortar bars expansion was measured versus time and aggregates with potential ASR problems were detected. Different types of supplementary cementitious materials (SCMs) were used in remixing mortar bars with highly reactive aggregates. Length changes for remixed bars proved that different types of SCMs can be successfully used in reducing the expansive effect of ASR. SCMs percentage by weight is highly dependent on the SCM type. The result of this study will help avoiding future losses due to ASR cracking in construction project and reduce the maintenance, repair, and replacement budgets required for highways network.

Keywords: alkali silica reaction, aggregates, misture, cracks, Mortar Bar Test, supplementary cementitious materials

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Authors: Italo Luigi de Paoli

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The use of synthetic soil for the vegetables cultivation in conditions of limited water consumption The separate collection of urban organic waste and green waste for the countries of the European Union averages 100 kg / inhabitant x year with an annual growth of about 10%. The production of quality compost averages 38% - 40% of the production of organic waste material. Most of the compost produced is used as an organic soil improver in those nutrient-poor soils in order to improve its quality. This study seeks to enhance the production of quality compost by creating a synthetic soil, where the percentages of compost on average oscillate between 50% and 60% in which, with appropriate precautions, different species of horticultural can be grown in conditions of high environmental safety without the use of pesticides and with a consumption of water used for irrigation limited to the actual evaporation of the plants. The project started in 2018 and is still ongoing, confirms its validity through a series of different horticultural productions, especially if this technology is applied where the availability of land suitable for the cultivation of vegetables is limited and where the use of water for irrigation represents a cultural criticality. Furthermore, the creation of "open field" crops, together with their automation, represents a further possibility in the concrete development of such technologies, giving the final product organoleptic characteristics equal if not superior to what the market offers today for human nutrition.

Keywords: water scarcity, compost, vegetable foods, syntetic soil

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Authors: Vishavjeet Singh Goraya, Bashir Ahmed Dar

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Sikhism is one of the youngest religions which came into existence only 550 years ago with Guru Nanak Dev. Guru Nanak and his successors not only gave religious sermons but also made bold commentaries on the politico-social situations of their times. Sikhism has consistently stood against autocratic regimes and societal polarization. The Sikh Gurus envisioned a political system based on equality, brotherhood, freedom of conscience, justice, and secularism where there was no discrimination and human rights of all were protected. The Sikh Gurus visualized a society based on an amalgamation of politics and religion without compromising morality and resisting any form of oppression and tyranny. The fifth guru of the Sikhs, Guru Arjan Dev, compiled the verses of his predecessors and many other saints belonging to different religions and castes in the form of Adi Granth, highlighting the egalitarian and secular foundations of Sikhism. Later tenth guru, Guru Gobind Singh, gave a concrete shape to the concepts of the earlier gurus written in Adi Granth and created an openly political and sovereign community known as Khalsa Panth with a distinct identity. This paper will use the qualitative historical approach to highlight Sikhism’s enduring commitment to fight oppression and tyranny, and it also examines how Sikhism offers solutions to contemporary issues of authoritarianism and polarization.

Keywords: sikhism, Gurus, political thought, equality, scriptures

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Authors: Tarek Litim, Ouahiba Taamallah

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Burnishing is a mechanical surface treatment that combines several beneficial effects on the two steel grades studied. The application of burnishing to the ball or to the tip favors a better roughness compared to turning. In addition, it allows the consolidation of the surface layers through work hardening phenomena. The optimal effects are closely related to the treatment parameters and the active part of the device. With an improvement of 78% on the roughness, burnishing can be defined as a finishing operation in the machining range. With a 44% gain in consolidation rate, this treatment is an effective process for material consolidation. These effects are affected by several factors. The factors V, f, P, r, and i have the most significant effects on both roughness and hardness. Ball or tip burnishing leads to the consolidation of the surface layers of both grades 100C6 and 16NC6 steels by work hardening. For each steel grade and its mechanical treatment, the rational tensile curve has been drawn. Lüdwick's law is used to better plot the work hardening curve. For both grades, a material hardening law is established. For 100C6 steel, these results show a work hardening coefficient and a consolidation rate of 0.513 and 44, respectively, compared to the surface layers processed by turning. When 16NC6 steel is processed, the work hardening coefficient is about 0.29. Hardness tests characterize well the burnished depth. The layer affected by work hardening can reach up to 0.4 mm. Simulation of the tests is of great importance to provide the details at the local scale of the material. Conventional tensile curves provide a satisfactory indication of the toughness of 100C6 and 16NC6 materials. A simulation of the tensile curves revealed good agreement between the experimental and simulation results for both steels.

Keywords: 100C6 steel, 16NC6 steel, burnishing, work hardening, roughness, hardness

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Authors: Qiong Tian, Lifeng Zhang, Demei Yu, Ajit D. Kelkar

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Low specific weight and high strength is the basic requirement for aerospace materials. Fiber-reinforced epoxy resin composites are attractive materials for this purpose. Boron nitride nanoparticles (BNNPs) have good radiation shielding capacity, which is very important to aerospace materials. Herein a processing route for an advanced hybrid composite material is demonstrated by introducing dispersed BNNPs in standard prepreg manufacturing. The hybrid materials contain three parts: E-fiberglass, an aerospace-grade epoxy resin system, and BNNPs. A vacuum assisted resin transfer molding (VARTM) was utilized in this processing. Two BNNP functionalization approaches are presented in this study: (a) covalent functionalization with 3-aminopropyltriethoxysilane (KH-550); (b) non-covalent functionalization with cetyltrimethylammonium bromide (CTAB). The functionalized BNNPs were characterized by Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction(XRD) and scanning electron microscope (SEM). The results showed that BN powder was successfully functionalized via the covalent and non-covalent approaches without any crystal structure change and big agglomerate particles were broken into platelet-like nanoparticles (BNNPs) after functionalization. Compared to pristine BN powder, surface modified BNNPs could result in significant improvement in mechanical properties such as tensile, flexural and compressive strength and modulus. CTAB functionalized BNNPs (CTAB-BNNPs) showed higher tensile and flexural strength but lower compressive strength than KH-550 functionalized BNNPs (KH550-BNNPs). These reinforcements are mainly attributed to good BNNPs dispersion and interfacial adhesion between epoxy matrix and BNNPs. This study reveals the potential in improving mechanical properties of BNNPs-containing composites laminates through surface functionalization of BNNPs.

Keywords: boron nitride, epoxy, functionalization, prepreg, composite

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Authors: Isaac Benning

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Using technology to expand the learning space is critical for a productive mathematical discourse. This is a case study of two teachers who developed and enacted GeoGebra-based mathematics lessons following their engagement in a two-year professional development. The didactical and semiotic affordance of GeoGebra in widening the learning space for a productive mathematical discourse was explored. The approach of thematic analysis was used for lesson artefact, lesson observation, and interview data. The results indicated that constructing tools in GeoGebra provided a didactical milieu where students used them to explore mathematical concepts with little or no support from their teacher. The prompt feedback from the GeoGebra motivated students to practice mathematical concepts repeatedly in which they privately rethink their solutions before comparing their answers with that of their colleagues. The constructing tools enhanced self-discovery, team spirit, and dialogue among students. With regards to the semiotic construct, the tools widened the physical and psychological atmosphere of the classroom by providing animations that served as virtual concrete to enhance the recording, manipulation, testing of a mathematical idea, construction, and interpretation of geometric objects. These findings advance the discussion of widening the classroom for a productive mathematical discourse within the context of the mathematics curriculum of Ghana and similar Sub-Saharan African countries.

Keywords: GeoGebra, theory of didactical situation, semiotic mediation, mathematics laboratory, mathematical discussion

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Authors: W. H. Lee, T. W. Cheng, K. Y. Lin, S. W. Huang, Y. C. Ding

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Basic Oxygen Furnace (BOF) Slag and electric arc furnace (EAF) slag is the by-product of iron making and steel making. Each of slag with produced over 100 million tons annually in Taiwan. The type of slag has great engineering properties, such as, high hardness and density, high compressive strength, low abrasion ratio, and can replace natural aggregate for building materials. However, no matter BOF or EAF slag, both have the expansion problem, due to it contains free lime. The purpose of this study was to stabilize the BOF and EAF slag by using geopolymer technology, hoping can prevent and solve the expansion problem. The experimental results showed that using geopolymer technology can successfully solve and prevent the expansion problem. Their main properties are analyzed with regard to their use as building materials. Autoclave is used to study the volume stability of these specimens. Finally, the compressive strength of geopolymer mortar with BOF/FAF slag can be reached over 21MPa after curing for 28 days. After autoclave testing, the volume expansion does not exceed 0.2%. Even after the autoclave test, the compressive strength can be grown to over 35MPa. In this study have success using these results on ready-mixed concrete plant, and have the same experimental results as laboratory scale. These results gave encouragement that the stabilized and reutilized BOF/EAF slag could be replaced as a feasible natural fine aggregate by using geopolymer technology.

Keywords: BOF slag, EAF slag, autoclave test, geopolymer

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Authors: Lakshmikanth Reddy, Bhavin Desai, Chandrakala Kari, Sanjay Sarkar, Pradeep Binu

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The sulphur dioxide gases generated as a by-product of smelting and converting operations of copper concentrate contain selenium apart from zinc, lead, copper, cadmium, bismuth, antimony, and arsenic. The gaseous stream is treated in waste heat boiler, electrostatic precipitator and scrubbers to remove coarse particulate matter in order to produce commercial grade sulfuric acid. The gas cleaning section of the acid plant uses water to scrub the smelting gases. After scrubbing, the sludge settled at the bottom of the scrubber, was analyzed in present investigation. It was found to contain 30 to 40 wt% copper and selenium up to 40 wt% selenium. The sludge collected during blow-down is directly recycled to the smelter for copper recovery. However, the selenium is expected to again vaporize due to high oxidation potential during smelting and converting, causing accumulation of selenium in sludge. In present investigation, a roasting process has been developed to recover the selenium before the copper recovery from the sludge at smelter. Selenium is associated with copper in sludge as copper selenide, as determined by X-ray diffraction and electron microscopy. The thermodynamic and thermos-gravimetry study revealed that the copper selenide phase present in the sludge was amenable to oxidation at 600°C forming oxides of copper and selenium (Cu-Se-O). However, the dissociation of selenium from the copper oxide was made possible by sulfatation using sulfur dioxide between 450 to 600°C, resulting into the formation of CuSO₄ (s) and SeO₂ (g). Lab scale trials were carried out in vertical tubular furnace to determine the optimum roasting conditions with respect to roasting time, temperature and molar ratio of O₂:SO₂. Using these optimum conditions, selenium up to 90 wt% in the form of SeO₂ vapors could be recovered from the sludge in a large-scale commercial roaster. Roasted sludge free from the selenium and containing oxides and sulfates of copper could now be recycled in the smelter for copper recovery.

Keywords: copper, selenium, copper selenide, sludge, roasting, SeO₂

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Authors: A. L. I. Prasanna, E. Liyanage, S. A. Rajaratne, K. P. A. P. Kariyawasam, A. A. J. Rajaratne

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Maintaining or improving the muscle strength of the injured body part is essential to optimize performance among disabled athletes. General conditioning and strengthening exercises might be ineffective if not sufficiently intense enough or targeted for each participant’s specific impairment. Specific strengthening programme, targeted to the affected body part, are essential to improve the strength of impaired muscles and increase in strength will help reducing the impact of disability. Methods: The muscle strength of hip, knee and ankle joints was assessed in a group of randomly selected disabled athletes, using the Medical Research Council (MRC) grading. Those having muscle strength of grade 4 or less were selected for this study (24 in number) and were given and a custom made exercise program designed to strengthen their hip, knee or ankle joint musculature, according to the muscle or group of muscles affected. Effectiveness of the strengthening program was assessed after a period of 3 months. Results: Statistical analysis was done using the Minitab 16 statistical software. A Mann-Whitney U test was used to compare the strength of muscle group before and after exercise programme. A significant difference was observed after the three month strengthening program for knee flexors (Left and Right) (P =0.0889, 0.0312) hip flexors (left and right) (P=0.0312, 0.0466), hip extensors (Left and Right) (P=0.0478, 0.0513), ankle plantar flexors (Left and Right) (P=0.0466, 0.0423) and right ankle dorsiflexors (P= 0.0337). No significant difference of strength was observed after the strengthening program in the knee extensors (left and right), hip abductors (left and right) and left ankle dorsiflexors. Conclusion: Impairment specific exercise programme appear to be beneficial for disabled athletes to significantly improve the muscle strength of the affected joints.

Keywords: muscle strengthening programme, disabled athletes, physiotherapy, rehabilitation sciences

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Authors: Mariem Meddeb Sidhom, Souhayel Hedfi, Rjaibia Houda, Mehdi Dridi, Mohamed Ali Yousfi, Sâadia Gargouri

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Considering the important increase in costs of caspofungin treatments and ahead the evolution of its indication, pharmacy department was prompted to realize a review of the adequacy of prescriptions in the medical intensive care units (ICU). A retrospective observational study was conducted in Tunis military hospital concerning ICU prescriptions of caspofungin from 2008 until 2013. A pharmacist had returned to the patient’s medical records to collect data and to the microbiology department for parasitological results. The adequacy of prescriptions was evaluated by a pharmacist and an infectiologist parasitologist, referring to predefined scale of criteria resuming the indications of the marketing authorization (MA) and grade AI-AII of the guidelines of the Infectious Diseases Society of America (IDSA). Sixty two ICU patients have been treated with caspofungin during the period of study; however, 8 files were lost. Thus, 54 patients were included in the study having received 55 prescriptions of caspofungin. Males were a majority with 64.8% of the population. Mean age was 51 years. Caspofungin was indicated in accordance with the IDSA recommendations in 43.6% of the cases. The most case of non respect to the guidelines was the indication of caspofungin as empirical treatment in non neutropenic patients. Caspofungin was utilized as a first line treatment in 9 cases where it was possible to give fluconazole first, as germs were fluconazole- sensitive. Caspofungin was indicated in 2 patients with good renal function and in which nor amphotericin B, liposomal ampho B neither itraconazole had been previously used, as indicates the MA. The posology of caspofungin was respected in all prescriptions with a loading dose of 70 mg in the first day and a maintenance dose of 50 mg daily. Seven patients had received a daily dose of 70 mg, the recommended dose for people weighing more than 80 Kg. Caspofungin prescriptions are far to be adequately done. There is a clear need of optimization in indicating this molecule and that must be done in collaboration between the pharmacy department, the ICUs and parasitology department.

Keywords: caspofungin, prescription, intensive care units, marketing authorization, Tunisian hospital cohort

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Authors: Muhammad Tariq A. Chaudhary

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Soil-structure interaction (SSI) in bridges under seismic excitation is a complex phenomenon which involves coupling between the non-linear behavior of bridge pier columns and SSI in the soil-foundation part. It is a common practice in the study of SSI to model the bridge piers as linear elastic while treating the soil and foundation with a non-linear or an equivalent linear modeling approach. Consequently, the contribution of soil and foundation to the SSI phenomenon is disproportionately highlighted. The present study considered non-linear behavior of bridge piers in FEM model of a 4-span, pile-supported bridge that was designed for five different soil conditions in a moderate seismic zone. The FEM model of the bridge system was subjected to a suite of 21 actual ground motions representative of three levels of earthquake hazard (i.e. Design Basis Earthquake, Functional Evaluation Earthquake and Maximum Considered Earthquake). Results of the FEM analysis were used to delineate the influence of pier column non-linearity and SSI on critical design parameters of the bridge system. It was found that pier column non-linearity influenced the bridge lateral displacement and base shear more than SSI for majority of the analysis cases for the class of bridge investigated in the study.

Keywords: bridge, FEM model, reinforced concrete pier, pile foundation, seismic loading, soil-structure interaction

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Authors: I. R. Keke, C. S. Nwigwe, O. S. Nwanjo, A. S. Egeruoh

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An experiment was carried out at Urban Farm and Fisheries Nigeria Ltd, Owerri Imo State South East Nigeria between February and June 2014 to induce Brood stock of Heterobranchus longifilis (mean wt 1.3kg) in concrete tanks (1.0 x 2.0 x 1.5m) in dimension using a synthetic hormone (Ovaprim) and pituitary extract from Heterobranchus longifilis. Brood stock males were selected as pituitary donors and their weights matched those of females to be injected at 1ml/kg body weight of Fish. Ovaprim, was injected at 0.5ml/kg body weight of female fish. A latency period of 12 hours was allowed after injection of the Brood stock females before stripping the egg and incubation at 23 °C. While incubating the eggs, samples were drawn and the rate of fertilization was determined. Hatching occurred within 33 hours and hatchability rate (%) was determined by counting the active hatchings. The result showed that Ovaprim injected Brood stock eggs fertilized up to 80% while the pituitary from the Heterobranchus longifilis had low fertilization and hatching success 20%. Ovaprim is imported and costly, so more effort is required to enhance the procedures for homoplastic hypophysation.

Keywords: heterobranchus longifilis, ovaprim, hypophysation, latency period, pituitary

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Authors: Nor-Edine Abriak, Ilyas Ennahal, Abdeljalil Zri, Mahfoud Benzerzour

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Nord Pas de Calais is one of the French regions that records a large volume of dredged sediment in harbors and waterways. To ensure navigation within ports and waterways, harbor and river managers are forced to find solutions to remove sediment that contamination levels exceed levels established by regulations. Therefore, this non- submersible sediment must be managed on land and will be subject to the waste regulation. In this paper, some examples of concrete achievements and experiments of reusing dredged sediment in civil engineering and sector will be illustrated. These achievements are alternative solutions to sediment landfilling and guarantee the reuse of this material in a logic of circular economy and ecological transition. It permits to preserve the natural resources increasingly scarce and resolve issues related to the accumulation of sediments in the harbor basins, rivers, dams, and lakes, etc. Examples of beneficial use of dredged material illustrated in this paper are the result of different projects reusing harbor and waterways sediments in several applications. These projects were funded under the national SEDIMATERIAUX approach. Thus the technical and environmental feasibility of the reuse of dredged sediment is demonstrated and verified; the dredged sediment reusing would meet multiple challenges of sustainable development in relation to environmental, economic, social and societal.

Keywords: circular economy, sediment, SEDIMATERIAUX, waterways

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Authors: Zahrasadat Hosseini, Jie Yuan

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Point-of-care (POC) diagnostic devices based on lab-on-a-chip (LOC) technology have the potential to revolutionize medical diagnostics. However, the development of an ideal microfluidic system based on LOC technology for diagnostics purposes requires overcoming several obstacles, such as improving sensitivity, selectivity, portability, cost-effectiveness, and prototyping methods. While numerous studies have introduced technologies and systems that advance these criteria, existing systems still have limitations. Electrochemical enzyme-linked immunosorbent assay (e-ELISA) in a LOC device offers numerous advantages, including enhanced sensitivity, decreased turnaround time, minimized sample and analyte consumption, reduced cost, disposability, and suitability for miniaturization, integration, and multiplexing. In this study, we present a novel design and fabrication method for a microfluidic diagnostic platform that integrates screen-printed electrochemical carbon/silver chloride electrodes on flexible printed circuit boards with flexible, multilayer, polydimethylsiloxane (PDMS) microfluidic networks to accurately manipulate and pre-immobilize analytes for performing electrochemical enzyme-linked immunosorbent assay (e-ELISA) for multiplexed quantification of blood serum biomarkers. We further demonstrate fast, cost-effective prototyping, as well as accurate and reliable detection performance of this device for quantification of interleukin-6-spiked samples through electrochemical analytics methods. We anticipate that our invention represents a significant step towards the development of user-friendly, portable, medical-grade, POC diagnostic devices.

Keywords: lab-on-a-chip, point-of-care diagnostics, electrochemical ELISA, biomarker quantification, fast prototyping

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Authors: Zahrasadat Hosseini, Jie Yuan

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Point-of-care (POC) diagnostic devices based on lab-on-a-chip (LOC) technology have the potential to revolutionize medical diagnostics. However, the development of an ideal microfluidic system based on LOC technology for diagnostics purposes requires overcoming several obstacles, such as improving sensitivity, selectivity, portability, cost-effectiveness, and prototyping methods. While numerous studies have introduced technologies and systems that advance these criteria, existing systems still have limitations. Electrochemical enzyme-linked immunosorbent assay (e-ELISA) in a LOC device offers numerous advantages, including enhanced sensitivity, decreased turnaround time, minimized sample and analyte consumption, reduced cost, disposability, and suitability for miniaturization, integration, and multiplexing. In this study, we present a novel design and fabrication method for a microfluidic diagnostic platform that integrates screen-printed electrochemical carbon/silver chloride electrodes on flexible printed circuit boards with flexible, multilayer, polydimethylsiloxane (PDMS) microfluidic networks to accurately manipulate and pre-immobilize analytes for performing electrochemical enzyme-linked immunosorbent assay (e-ELISA) for multiplexed quantification of blood serum biomarkers. We further demonstrate fast, cost-effective prototyping, as well as accurate and reliable detection performance of this device for quantification of interleukin-6-spiked samples through electrochemical analytics methods. We anticipate that our invention represents a significant step towards the development of user-friendly, portable, medical-grade POC diagnostic devices.

Keywords: lab-on-a-chip, point-of-care diagnostics, electrochemical ELISA, biomarker quantification, fast prototyping

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Authors: Vidhi Chandra, Arshpreet Singh Grewal

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A five-year-old male child born from non-consanguineous marriage, who presented with complaints of growth retardation and no appreciable increase in the penile size since birth and he was posted for de-gloving of penis with dissection of corpora under anaesthesia. After thorough preoperative evaluation it was revealed that patient had peculiar facial dysmorphism that of Robinow Syndrome, high arched palate, Mallampati grade III, mesomelic limbs, scoliotic spine and short stature. All routine investigation were within normal limit, electrocardiography (ECG) and 2D-Echocardiography (ECHO) were normal. In antero-posterior roentgenogram chest showed butterfly and hemivertebrae at multiple levels. The patient was considered to be ASA II. On the day of surgery after ensuring fasting of 6 hours, patient was taken in operation theatre, all standard ASA monitoring was done with ECG, non-invasive blood pressure, peripheral oxygen saturation (SpO2) and body temperature. The patient was pre-oxygenated with 100% oxygen with anatomical face mask. General anaesthesia was induced with Sevoflurane 1-8%, and airway was secured with an appropriate size supraglottic airway and anaesthesia was maintained with nitrous oxide and oxygen in 1:1 ratio along with sevoflurane 2%. An ultrasound guided caudal block was given owing to the skeletal deformities making it difficult even under USG guidance. Post operatively patient was given supportive care with proper hydration, antibiotics, anti-inflammatory and analgesics. He was discharged the next day and followed up weekly for a month. DISCUSSION Robinow syndrome is genetically inherited as autosomal dominant, autosomal recessive or heterogenous disorder involving tyrosine kinase ROR2 gene located on chromosome 9. It has low incidence with no preponderance for any gender. Though intelligence is normal but developmental delay and mental retardation occurs in 20%cases

Keywords: Robinow Syndrome, dwarfism, paediatric, anaesthesia

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Authors: Xin Li, Yan-Rong Guo, Jin-Fang Lin, Yi Feng, Håkan Billig, Ruijin Shao

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Background: Young women with polycystic ovary syndrome (PCOS) have a high risk of developing endometrial carcinoma. There is a need for the development of new medical therapies that can reduce the need for surgical intervention so as to preserve the fertility of these patients. The aim of the study was to describe and discuss cases of PCOS and insulin resistance (IR) women with early endometrial carcinoma while being co-treated with Diane-35 and metformin. Methods: Five PCOS-IR women who were scheduled for diagnosis and therapy for early endometrial carcinoma were recruited. The hospital records and endometrial pathology reports were reviewed. All patients were co-treated with Diane-35 and metformin for 6 months to reverse the endometrial carcinoma and preserve their fertility. Before, during, and after treatment, endometrial biopsies and blood samples were obtained and oral glucose tolerance tests were performed. Endometrial pathology was evaluated. Body weight (BW), body mass index (BMI), follicle-stimulating hormone (FSH), luteinizing hormone (LH), total testosterone (TT), sex hormone-binding globulin (SHBG), free androgen index (FAI), insulin area under curve (IAUC), and homeostasis model assessment of insulin resistance (HOMA-IR) were determined. Results: Clinical stage 1a, low grade endometrial carcinoma was confirmed before treatment. After 6 months of co-treatment, all patients showed normal epithelia. No evidence of atypical hyperplasia or endometrial carcinoma was found. Co-treatment resulted in significant decreases in BW, BMI, TT, FAI, IAUC, and HOMA-IR in parallel with a significant increase in SHBG. There were no differences in the FSH and LH levels after co-treatment. Conclusions: Combined treatment with Diane-35 and metformin has the potential to revert the endometrial carcinoma into normal endometrial cells in PCOS-IR women. The cellular and molecular mechanisms behind this effect merit further investigation.

Keywords: PCOS, progesterone resistance, insulin resistance, steroid hormone receptors, endometrial carcinoma

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Authors: Yina F. Muñoz, Alexander Paz, Hanns De La Fuente-Mella, Joaquin V. Fariña, Guilherme M. Sales

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The primary approach for estimating bridge deterioration uses Markov-chain models and regression analysis. Traditional Markov models have problems in estimating the required transition probabilities when a small sample size is used. Often, reliable bridge data have not been taken over large periods, thus large data sets may not be available. This study presents an important change to the traditional approach by using the Small Data Method to estimate transition probabilities. The results illustrate that the Small Data Method and traditional approach both provide similar estimates; however, the former method provides results that are more conservative. That is, Small Data Method provided slightly lower than expected bridge condition ratings compared with the traditional approach. Considering that bridges are critical infrastructures, the Small Data Method, which uses more information and provides more conservative estimates, may be more appropriate when the available sample size is small. In addition, regression analysis was used to calculate bridge deterioration. Condition ratings were determined for bridge groups, and the best regression model was selected for each group. The results obtained were very similar to those obtained when using Markov chains; however, it is desirable to use more data for better results.

Keywords: concrete bridges, deterioration, Markov chains, probability matrix

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Authors: Abebe Tibebu

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This study investigates the quality of training factors in Ethiopian Technical and Vocational Education and Training (TVET) colleges and their impact on declining enrollment rates. Employing a descriptive survey design, both quantitative and qualitative data were collected from diverse stakeholders, including Grade 12 graduates, current TVET trainees, trainers, college deans, community members, high school directors, teachers, and officials from TVET government agencies. The sample included 20 TVET centers from various Ethiopian regions. Secondary data were obtained from college and government documents, while primary data were gathered through questionnaires, interviews, focus group discussions, and observations. Analysis was conducted using descriptive statistics with SPSS, capturing response frequencies and percentages. The study's findings highlight several key factors affecting TVET enrollment: limited infrastructure capacity, insufficient trainer competency, misaligned curriculum, low-quality training delivery particularly in cooperative training implementation and industry partnership and low success rates on Certification of Competency (CoC) exams. Many TVET institutions lack qualified trainers, adequate machinery, and timely provision of materials for practical skills training. Based on these findings, the study recommends enhanced infrastructure investment, professional development for trainers, curriculum adjustments to better align with industry needs, and standardized assessment practices. Addressing these areas through collaborative efforts with government bodies and industry stakeholders is essential to improving the quality and appeal of Ethiopian TVET programs, ultimately strengthening enrollment and outcomes.

Keywords: TVET, quality factors, enrollment, potentially enrolled

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Authors: Koyar Rane

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Nano- to submicron size particles of narrow particle size distribution of semi-conducting TiO₂, ZnO, NiO, CuO, Fe₂O₃ have been synthesized by novel hydrazine method and tested for their gas sensing, photocatalytic and bactericidal activities and the behavior found to be enhanced when the oxides in the thin film forms, that obtained in a specially built spray pyrolysis reactor. Hydrazine method is novel in the sense, say, the UV absorption edge of the white pigment grade wide band gap (~3.2eV) TiO₂ and ZnO shifted to the visible region turning into yellowish particles, indicating modification occurring the band structure. The absorption in the visible region makes these oxides visible light sensitive photocatalysis in degrading pollutants, especially the organic dyes which otherwise increase the chemical oxygen demand of the drinking water, enabling the process feasible not under the harsh energetic UV radiation regime. The electromagnetic radiations on irradiation produce electron-hole pairs Semiconductor + hν → e⁻ + h⁺ The electron-hole pairs thus produced form Reactive Oxygen Species, ROS, on the surface of the semiconductors, O₂(adsorbed)+e⁻ → O₂• - superoxide ion OH-(surface)+h⁺ →•OH - Hydroxyl radical The ROS attack the organic material and micro-organisms. Our antibacterial studies indicate the metal oxides control the Biological Oxygen Demand (BOD) of drinking water which had beyond the safe level normally found in the municipal supply. Metal oxides in the thin film form show overall enhanced properties and the films are reusable. The results of the photodegradation and antibactericidal studies are discussed. Gas sensing studies too have been done to find the versatility of the multifunctional metal oxides.

Keywords: hydrazine method, visible light sensitive, photo-degradation of dyes, water/airborne pollutant

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Authors: Temesgen Oljira, Olugbenga Akindeji Okunlola, Akinade Shadrach Olatunji, Dereje Ayalew, Bekele Ayele Bedada

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The Western Ethiopian Shield (WES) is underlain by volcano-sedimentary terranes, gneissic terranes, and ophiolitic rocks intruded by different granitoid bodies. For the past few years, Neoproterozoic rocks of the Megele area in the western part of the WES have been explored. Understanding the geology of the area and assessing the mineralized area's economic potential requires petrological, geochemical, and geological characterization of the Neoproterozoic granitoids and associated metavolcanic rocks. Thus, the geological, geochemical, and petrogenetic features of Neoproterozoic granitoids and associated metavolcanic rocks were elucidated using a combination of field mapping, petrological, and geochemical study. The Megele area is part of a low-grade volcano-sedimentary zone that has been intruded by mafic (dolerite dyke) and granitoid intrusions (granodiorite, diorite, granite gneiss). The granodiorite, associated diorite, and granite gneiss are calc-alkaline, peraluminous to slightly metaluminous, S-type granitoids formed in volcanic arc subduction (VAG) to syn-collisional (syn-COLD) tectonic setting by fractionation of LREE-enriched, HREE-depleted basaltic magma with considerable crustal input. While the metabasalt is sub-alkaline (tholeiitic), metaluminous bodies are generated at the mid-oceanic ridge tectonic setting by partially melting HREE-depleted and LREE-enriched basaltic magma. The reworking of sediment-loaded crustal blocks at depth in a subduction zone resulted in the production of S-type granitoids. This basaltic magma was supplied from an LREE-enriched, HREE-depleted mantle.

Keywords: fractional crystallization, geochemistry, Megele, petrogenesis, s-type granite

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Authors: Xiao Zhang, Wensheng Xiao, Junguo Cui, Hongmin Wang

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Submersible permanent magnet linear synchronous motors (SPMLSMs) are electromagnetic devices, which can directly drive plunger pump to obtain the crude oil. Those motors have been gradually applied in oil fields due to high thrust force density and high efficiency. Since the force performance closely depends on the concrete structural parameters, the seven different structural parameters are investigated in detail. This paper presents an optimum design of an SPMLSM to minimize the detent force and maximize the thrust by using design of experiment (DOE) and genetic algorithm (GA). The three significant structural parameters (air-gap length, slot width, pole-arc coefficient) are separately screened using 27 1/16 fractional factorial design (FFD) to investigate the significant effect of seven parameters used in this research on the force performance. Response surface methodology (RSM) is well adapted to make analytical model of thrust and detent force with constraints of corresponding significant parameters and enable objective function to be easily created, respectively. GA is performed as a searching tool to search for the Pareto-optimal solutions. By finite element analysis, the proposed PMLSM shows merits in improving thrust and reducing the detent force dramatically.

Keywords: optimization, force performance, design of experiment (DOE), genetic algorithm (GA)

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Authors: Mohammad Hossein Karimi Darvanjooghi, Sara Magdouli, Satinder Kaur Brar

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It has been reported that the microorganism’s attachment to the surfaces of ore samples is a key factor that influences the biooxidation in pretreatment for recovery of gold in sulfide-bearing ores. In this research, the implementation of D-(+)-Sucrose on the biooxidation of ore samples were studied in a semi-pilot experiment. The experiments were carried out in five separate jacketed columns (1 m height and 6 cm diameter) at a constant temperature of 37.5 ̊C and saturated humidity. The airflow rate and recycling solution flow rate were studied in the research and the optimum operating condition were reported. The ore sample (0.49 ppm gold grade) was obtained from the Hammond Reef mine site containing 15 wt.% of pyrite which included 98% of gold according to the results of micrograph images. The experiments were continued up to 100 days while air flow rates were chosen to be 0.5, 1, 1.5, 2, and 3 lit/min and the recycling solution (Containing 9K media and 0.4 wt.% D-(+)-Sucrose) flow rates were kept 5, 8, 15 ml/hr. The results indicated that the addition of D-(+)-Sucrose increased the bacterial activity due to the overproduction of extracellular polymeric substance (EPS) up to 95% and for the condition that the recycling solution and air flow rate were chosen to be 8 ml/hr and 2 lit/min, respectively, the maximum pyrite dissolution of 76% was obtained after 60 days. The results indicated that for the air flow rates of 0.5, 1, 1.5, 2, and 3 lit/min the ratio of daily pyrite dissolution per daily solution lost were found to be 0.025, 0.033, 0.031, 0.043, and 0.009 %-pyrite dissolution/ml-lost. The implementation of this microorganisms and the addition of D-(+)-Sucrose will enhance the efficiency of gold recovery through faster biooxidation process and leads to decrease in the time and energy of operation toward desired target; however, still other parameters including particle size distribution, agglomeration, aeration design, chemistry of recycling solution need to be controlled and monitored for reaching the optimum condition.

Keywords: column tests, biooxidation, gold recovery, Ferroplasma acidophilum, optimization

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Authors: Jawid Ahmad Baktash, Tadashi Shiroma, Tomokazu Nagata, Yuji Taniguchi, Morikazu Nakamura

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The goal of this paper is to explore the use of formal methods for Dynamic Routing, The purpose of network communication with dynamic routing is sending a massage from one node to others by using pacific protocols. In dynamic routing connections are possible based on protocols of Distance vector (Routing Information Protocol, Border Gateway protocol), Link State (Open Shortest Path First, Intermediate system Intermediate System), Hybrid (Enhanced Interior Gateway Routing Protocol). The responsibility for proper verification becomes crucial with Dynamic Routing. Formal methods can play an essential role in the Routing, development of Networks and testing of distributed systems. Event-B is a formal technique consists of describing rigorously the problem; introduce solutions or details in the refinement steps to obtain more concrete specification, and verifying that proposed solutions are correct. The system is modeled in terms of an abstract state space using variables with set theoretic types and the events that modify state variables. Event-B is a variant of B, was designed for developing distributed systems. In Event-B, the events consist of guarded actions occurring spontaneously rather than being invoked. The invariant state properties must be satisfied by the variables and maintained by the activation of the events.

Keywords: dynamic rout RIP, formal method, event-B, pro-B

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Authors: Shanti Faridah Salleh, Azzahrah Anuar, Hamimah Ujir, Rohana Sapawi, Wan Hashim Wan Ibrahim, Noraziah Abdul Wahab, Majina Sulaiman, Raudhah Ahmadi, Al-Khalid Othman, Johari Abdullah

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Integrated Cumulative Grade Point Average or iCGPA is an evaluation and reporting system that represents a comprehensive development of students’ achievement in their academic programs. Universiti Malaysia Sarawak, UNIMAS has started its implementation of iCGPA in 2016. iCGPA is driven by the Outcome-Based Education (OBE) system that has been long integrated into the higher education in Malaysia. iCGPA is not only a tool to enhance the OBE concept through constructive alignment but it is also an integrated mechanism to assist various stakeholders in making decisions or planning for program improvement. The outcome of this integrated system is the reporting of students’ academic performance in terms of cognitive (knowledge), psychomotor (skills), and affective (attitude) of which the students acquire throughout the duration of their study. The iCGPA reporting illustrates the attainment of student’s attribute in the eight domains of learning outcomes listed in the Malaysian Qualifications Framework (MQF). This paper discusses on the implementation of iCGPA in UNIMAS on the policy and strategy to direct the whole university to implement the iCGPA. The steps and challenges in integrating the exsting Outcome-Based Education and utilising iCGPA as a tool to quantify the students’ achievement are also highlighted in this paper. Finally, the ACADEMIA system, which is a dedicated centralised program ensure the implementation of iCGPA is a success has been developed. This paper discusses the structure and the analysis of ACADEMIA program and concludes the analysis made on the improvement made on the implementation of constructive alignment in all 40 programs involves in iCGPA implementation.

Keywords: constructive alignment, holistic graduates, mapping of assessment, programme outcome

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Authors: Ariungerel Jargal

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: Cave mining is a bulk underground mining method, which allows large low-grade deposits to be mined underground. This method involves undermining the orebody to make it collapse under its own weight into a series of chambers from which the ore extracted. It is a useful technique to extend the life of large deposits previously mined by open pits, and it is a method increasingly proposed for new mines around the world. We plan to conduct a feasibility study using Electrical impedance tomography (EIT) technology to show how much subsidence there is at the intersection with the cave mining surface. EIT is an imaging technique which uses electrical measurements at electrodes attached on the body surface to yield a cross-sectional image of conductivity changes within the object. EIT has been developed in several different applications areas as a simpler, cheaper alternative to many other imaging methods. A low frequency current is injected between pairs of electrodes while voltage measurements are collected at all other electrode pairs. In the difference EIT, images are reconstructed of the change in conductivity distribution (σ) between the acquisition of the two sets of measurements. Image reconstruction in EIT requires the solution of an ill-conditioned nonlinear inverse problem on noisy data, typically requiring make simpler assumptions or regularization. It is noted that the ratio of current to voltage represents a complex value according to Ohm’s law, and that it is theoretically possible to re-express EIT. The results of the experiment were presented on the simulation, and it was concluded that it is possible to conduct further real experiments. Drill a certain number of holes in the top wall of the cave to attach the electrodes, flow a current through them, and measure and acquire the potential through these electrodes. Appropriate values should be selected depending on the distance between the holes, the frequency and duration of the measurements, the surface characteristics and the size of the study area using an EIT device.

Keywords: impedance tomography, cave mining, soil, EIT device

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Authors: Abhishek Pandey

Abstract:

Ibuprofen and Acetaminophen is widely used as prescription & non-prescription medicine. Ibuprofen mainly used in the treatment of mild to moderate pain related to headache, migraine, postoperative condition and in the management of spondylitis, osteoarthritis and rheumatoid arthritis. Acetaminophen is used as an analgesic and antipyretic drug. Ibuprofen having high tendency of sticking to punches of tablet punching machine while Acetaminophen is not ordinarily compressible to tablet formulation because Acetaminophen crystals are very hard and brittle in nature and fracture very easily when compressed producing capping and laminating tablet defects therefore wet granulation method is used to make them compressible. The aim of study was to prepare Ibuprofen and Acetaminophen tablets by direct compression and top spray granulation technique. In this Investigation tablets were prepared by using directly compressible grade excipients. Dibasic calcium phosphate, lactose anhydrous (DCL21), microcrystalline cellulose (Avicel PH 101). In order to obtain best or optimized formulation, nine different formulations were generated among them batch F7, F8, F9 shows good results and within the acceptable limit. Formulation (F7) selected as optimize product on the basis of dissolution study. Furtherly, directly compressible granules of both drugs were prepared by using top spray granulation technique in fluidized bed processor equipment and compressed .In order to obtain best product process optimization was carried out by performing four trials in which various parameters like inlet air temperature, spray rate, peristaltic pump rpm, % LOD, properties of granules, blending time and hardness were optimized. Batch T3 coined as optimized batch on the basis physical & chemical evaluation. Finally formulations prepared by both techniques were compared.

Keywords: direct compression, top spray granulation, process optimization, blending time

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Authors: Erika Mae L. Valencia

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Third Culture Kids (TCKs) are children who experienced a cross-cultural upbringing – being raised and lived outside their parents’ culture. As a result, TCKs experience the difficulty of building and attaining a concrete cultural identity. However, in the context of globalization and the emergence of ICTs, the internet, and mobile technology creates better ways of constructing cultural identities. This study investigates the social and cultural impacts of the internet and mobile technology on the multi-cultural identity development among selected Filipino TCKs. Moreover, this research seeks to understand how the Filipino TCKs form their identity and address their complex issue of belonging with the use of different internet platforms and mobile technology. To explore the lived experiences of Filipino TCKs, this research employs a transcendental phenomenological design. Also, this study uses purposive and snowball sampling and conduct in-depth interviews through Skype, phone call, or face-to-face. This study utilizes Pierre Bourdieu’s social capital as a theoretical lens to gain understanding of the TCKs’ identity formation process in relation to the said ICTs. This research argues that the internet and mobile technology play a significant role in facilitating multi-cultural identity formation of Filipino TCKs, as well as potentially broadening their social network through its various technological platforms.

Keywords: identity, internet, third culture kids, mobile technology

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Authors: Galih Permana, Yuskar Lase

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In recent years, damping device has been experimentally studied to replace diagonally reinforced coupling beams, to mitigate rebar congestion problem. This study focuses on evaluating the effectiveness of various damping devices in a high-rise building. The type of damping devices evaluated is Viscoelastic Damper (VCD) and Rotational Friction Damper (RFD), with study case of a 15-story reinforced concrete apartment building with a dual system (column-beam and shear walls). The analysis used is a nonlinear time history analysis with 11 pairs of ground motions matched to the Indonesian response spectrum based on ASCE 41-17 and ASCE 7-16. In this analysis, each damper will be varied with a different position, namely the first model, the damper will be installed on the entire floor and in the second model, the damper will be installed on the 5th floor to the 9th floor, which is the floor with the largest drift. The results show that the model using both dampers increases the level of structural performance both globally and locally in the building, which will reduce the level of damage to the structural elements. But between the two dampers, the coupling beam that uses RFD is more effective than using VCD in improving building performance. The damper on the coupling beam has a good role in dissipating earthquakes and also in terms of ease of installation.

Keywords: building, coupling beam, damper, nonlinear time history analysis

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Authors: Mannal Tariq

Abstract:

Construction industry is making progress at a high pace. The trend of the world is getting more biased towards the high rise buildings. Deep beams are one of the most common elements in modern construction having small span to depth ratio. Deep beams are mostly used as transfer girders. This experimental study consists of 16 reinforced concrete (RC) deep beams. These beams were divided into two groups; A and B. Groups A and B consist of eight beams each, having 381 mm (15 in) and 457 mm (18 in) depth respectively. Each group was further subdivided into four sub groups each consisting of two identical beams. Each subgroup was comprised of solid/control beam (without opening), opening above neutral axis (NA), at NA and below NA. Except for control beams, all beams with openings were strengthened with carbon fibre reinforced polymer (CFRP) vertical strips. These eight groups differ from each other based on depth and location of openings. For testing sake, all beams have been loaded with two symmetrical point loads. All beams have been designed based on strut and tie model concept. The outcome of experimental investigation elaborates the difference in the shear behaviour of deep beams based on depth and location of circular openings variation. 457 mm (18 in) deep beam with openings above NA show the highest strength and 381 mm (15 in) deep beam with openings below NA show the least strength. CFRP sheets played a vital role in increasing the shear capacity of beams.

Keywords: CFRP, deep beams, openings in deep beams, strut and tie modal, shear behaviour

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