Search results for: effective radiation dose

Authors: Misa Nakao, Yuta Kurashina, Chikahiro Imashiro, Kenjiro Takemura

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The Research Goal: With the growing demand for regenerative medicine, an effective mass cell culture process is required. In a repetitive subculture process for proliferating cells, preparing single cell suspension which does not contain any cell aggregates is highly required because cell aggregates often raise various undesirable phenomena, e.g., apoptosis and decrease of cell proliferation. Since cell aggregates often occur in cell suspension during conventional subculture processes, this study proposes a single cell sorter driven by a resonance vibration of a cell culture substrate. The Method and the Result: The single cell sorter is simply composed of a cell culture substrate and a glass pipe vertically placed against the cell culture substrate with a certain gap corresponding to a cell diameter. The cell culture substrate is made of biocompatible stainless steel with a piezoelectric ceramic disk glued to the bottom side. Applying AC voltage to the piezoelectric ceramic disk, an out-of-plane resonance vibration with a single nodal circle of the cell culture substrate can be excited at 5.5 kHz. By doing so, acoustic radiation force is emitted, and then cell suspension containing only single cells is pumped into the pipe and collected. This single cell sorter is effective to collect single cells selectively in spite of its quite simple structure. We collected C2C12 myoblast cell suspension by the single cell sorter with the vibration amplitude of 12 µmp-p and evaluated the ratio of single cells in number against the entire cells in the suspension. Additionally, we cultured the collected cells for 72 hrs and measured the number of cells after the cultivation in order to evaluate their proliferation. As a control sample, we also collected cell suspension by conventional pipetting, and evaluated the ratio of single cells and the number of cells after the 72-hour cultivation. The ratio of single cells in the cell suspension collected by the single cell sorter was 98.2%. This ratio was 9.6% higher than that collected by conventional pipetting (statistically significant). Moreover, the number of cells cultured for 72 hrs after the collection by the single cell sorter yielded statistically more cells than that collected by pipetting, resulting in a 13.6% increase in proliferated cells. These results suggest that the cell suspension collected by the single cell sorter driven by the resonance vibration hardly contains cell aggregates whose diameter is larger than the gap between the cell culture substrate and the pipe. Consequently, the cell suspension collected by the single cell sorter maintains high cell proliferation. Conclusions: In this study, we developed a single cell sorter capable of sorting and pumping single cells by a resonance vibration of a cell culture substrate. The experimental results show the single cell sorter collects single cell suspension which hardly contains cell aggregates. Furthermore, the collected cells show higher proliferation than that of cells collected by conventional pipetting. This means the resonance vibration of the cell culture substrate can benefit us with the increase in efficiency of mass cell culture process for clinical applications.

Keywords: acoustic radiation force, cell proliferation, regenerative medicine, resonance vibration, single cell sorter

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Authors: S. M. M. Nelwamondo, W. C. M. H. Meyer, H. Krieg

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The presence of volatile radionuclides in high level waste (HLW) in the nuclear industry limits the use of high temperature encapsulation technologies (glass and ceramic). Chemically bonded phosphate cement (CBPC) matrixes can be used for encapsulation of low level waste. This waste form is however not suitable for high level waste due to the radiolysis of water in these matrixes. In this research, the sintering behavior of the magnesium potassium phosphate cement waste forms was investigated. The addition of sintering aids resulted in the sintering of these phosphate cement matrixes into dense monoliths containing no water. Experimental evidence will be presented that this waste form can now be considered as a waste form for volatile radionuclides and high level waste as radiation studies indicated no chemical phase transition or physical degradation of this waste form.

Keywords: chemically bonded phosphate cements, HLW encapsulation, thermal stability, radiation stability

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Authors: Agnieszka Stempniewicz, Piotr Ceranowicz, Wojciech Macyk, Jakub Cieszkowski, Beata Kuśnierz-Cabała, Katarzyna Gałązka, Zygmunt Warzecha

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Objectives: There are numerous strategies for the prevention or treatment of oral mucositis. However, their effectiveness is limited and does not correspond to expectations. Recent studies have shown that obestatin exhibits a protective effect and accelerates the healing of gastrointestinal mucosa. The aim of the present study was to examine the influence of obestatin administration on oral ulcers in rats. Methods: lingual ulcers were induced by the use of acetic acid. Rats were treated twice a day intraperitoneally with saline or obestatin(4, 8, or 16 nmol/kg/dose) for five days. The study determined: lingual mucosa morphology, cell proliferation, mucosal blood flow, and mucosal pro-inflammatory interleukin-1β level(IL-1β). Results: In animals without induction of oral ulcers, treatment with obestatin was without any effect. Obestatin administration in rats with lingual ulcers increased the healing rate of these ulcers. Obestatin given at the dose of 8 or 16 nmol/kg/dose caused the strongest and similar therapeutic effect. This result was associated with a significant increase in blood flow and cell proliferation in gingival mucosa, as well as a significant decrease in IL-1β level. Conclusions: Obestatin accelerates the healing of lingual ulcers in rats. This therapeutic effect is well-correlated with an increase in blood flow and cell proliferation in oral mucosa, as well as a decrease in pro-inflammatory IL-1β levels. Obestatin is a potentially useful candidate for the prevention and treatment of oral mucositis. Acknowledgment: Agnieszka Stempniewicz acknowledges the support of InterDokMed project no. POWR.03.02.00- 00-I013/16.

Keywords: oral mucositis, ulcers, obestatin, lingual mucosa

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Authors: Natasa Todorovic, Jovana Nikolov

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Guard detector efficiency, cosmic background, and its variation were determinate using ultra low-level liquid scintillation spectrometer Quantulus 1220, equipped with an anti-Compton guard detector, in the surface laboratory at the University of Novi Sad, Serbia, Atmospheric pressure variation has an observable effect on the anti-Compton guard detector count rate. and the cosmic muon flux is lower during a high-pressure period. Also, the guard detector Compton continuum provides a good view of the level of gamma radiation in the laboratory environment. The efficiency of the guard detector in the channel interval from 750 to 1024 was assessed to 93.45%; efficiency in the entire window (channels 1 to 1024) was 75.23%, which is in good agreement with literature data.

Keywords: cosmic radiation, background reduction, liquid scintillation counting, guard detector efficiency

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Authors: Sangeeta Pilkhwal Sah, C. S. Mathela, Kanwaljit Chopra

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Valeriana wallichii DC, an ayurvedic traditional medicine, popularly named as Indian valerian exist as three chemotypes. GC-MS analysis of V. wallichii essential oil in present study showed maaliol as the major constituent followed by the presence of β-gurjunene, acoradiene, guaiol and α-santalene. The results thus confirmed it to be a maaliol chemotype. Further, the antidepressant-like effect of root essential oil (10, 20 and 40 mg/kg p.o.) was investigated in both acute and chronic treatment study using forced swim test in mice. Single administration of different doses produced an inverted U shaped curve and significantly inhibited the immobility period (39.7% and 58%) at doses 10 and 40 mg/kg respectively. Standard drug imipramine significantly decreased immobility period (59.8%). None of the doses altered locomotor activity except a significant decrease of 44.9% was observed with 40 mg/kg (p < 0.05). Similarly, daily administration of essential oil for 14 days produced a dose dependent effect with significantly reduced immobility period (70.9%) at 40 mg/kg dose only whereas imipramine produced 86% decrease (p < 0.05). The neurotransmitter levels in mouse brain were estimated on day 14 after the behavioral study. Significant increase in the level of norepinephrine (10%) and dopamine (23%) (p < 0.05) was found at 40 mg/kg dose, while no change was observed at 10 and 20 mg/kg doses. The antidepressant-like effect of essential oil (40 mg/kg) was prevented by pretreatment of mice with L-arginine (750 mg/kg i.p.) and sildenafil (5 mg/kg i.p). On the contrary, pretreatment of mice with L-NAME (10 mg/kg i.p.) or methylene blue (10 mg/kg i.p.) potentiated the antidepressant action of essential oil (20 mg/kg). The findings thus demonstrated that nitric oxide pathway is involved in mediating antidepressant like effect of essential oil from this chemotype.

Keywords: Valeriana wallichii DC chemotype, essential oil, forced swim test, nitric oxide modulators, neurotransmitters

Procedia PDF Downloads 293

Authors: Asher John Mohan, Krishna K. L.

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Objectives: (1) To assess the extent of memory impairment induced by Phenytoin (PHT) at normal and reduced dose on temporal lobe epileptic mice. (2) To evaluate the protective effect of Levetiracetam (LEV) on aggravation of memory impairment in temporal lobe epileptic mice by PHT. Materials and Methods: Albino mice of either sex (n=36) were used for the study for a period of 64 days. Convulsions were induced by intraperitoneal administration of pilocarpine 280 mg/kg on every 6th day. Radial arm maze (RAM) was employed to evaluate the memory impairment activity on every 7th day. The anticonvulsant and memory impairment activity were assessed in PHT normal and reduced doses both alone and in combination with LEV. RAM error scores and convulsive scores were the parameters considered for this study. Brain acetylcholine esterase and glutamate were determined along with histopathological studies of frontal cortex. Results: Administration of PHT for 64 days on mice has shown aggravation of memory impairment activity on temporal lobe epileptic mice. Although the reduction in PHT dose was found to decrease the degree of memory impairment the same decreased the anticonvulsant potency. The combination with LEV not only brought about the correction of impaired memory but also replaced the loss of potency due to the reduction of the dose of the antiepileptic drug employed. These findings were confirmed with enzyme and neurotransmitter levels in addition to histopathological studies. Conclusion: This study thus builds a foundation in combining a nootropic anticonvulsant with an antiepileptic drug to curb the adverse effect of memory impairment associated with temporal lobe epilepsy. However further extensive research is a must for the practical incorporation of this approach into disease therapy.

Keywords: anti-epileptic drug, Phenytoin, memory impairment, Pilocarpine

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Authors: Rajan Jakhu, Rohit Mehra

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Radon (²²²Rn) and its decay products are the major sources of natural radiation exposure to general population. The activity concentrations of radon, thoron gasses, and their unattached and attached short-lived progeny in indoor environment of the Jaipur and Ajmer districts of Rajasthan had been calculated via passive measurements using the Pinhole cup dosimeter, deposition based progeny sensors (DRPS/DTPS) and wire mesh capped (DRPS/DTPS) progeny sensors. The results of this study revealed that radon and thoron concentrations (CRn, CTn) are highest in the winter season. The variation of the radon and its decay products are observed to vary seasonally, but these environmental parameters seem not to be affecting the thoron and its decay product concentrations in a regular manner. The average values of the radon and its decay products are maximum in winter and minimum in summer. The equilibrium factor for radon is observed to be 0.50, 0.47 and 0.49 in winter, rainy and summer seasons. The annual average value of the unattached fraction of the radon progeny comes out to be 0.34. On the other hand, the average value of thoron (²²⁰Rn) concentration and its equilibrium factor in the studied area comes to be 74, 39, 45 Bq m⁻³ and 0.07, 0.11, 0.07 respectively for the winter, rainy and summer seasons with the annual average value of the unattached fraction of about 0.18. The annual average radiological dose from exposure to indoor radon and thoron progeny comes out to be 0.88 and 0.78 mSv.

Keywords: equilibrium factor, radon, seasonal variation, thoron, unattached fraction

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Authors: Jafar Khodagholizadeh

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In this talk, we study the tensor mode equation of perturbation in the presence of nonzero $-\Lambda$ as dark energy, whose dynamic nature depends on the Hubble parameter $ H$ and/or its time derivative. Dark energy, according to the total vacuum contribution, has little effect during the radiation-dominated era, but it reduces the squared amplitude of gravitational waves (GWs) up to $60\%$ for the wavelengths that enter the horizon during the matter-dominated era. Moreover, the observations bound on dark energy models, such as running vacuum model (RVM), generalized running vacuum model (GRVM), and generalized running vacuum subcase (GRVS), are effective in reducing the GWs’ amplitude. Although this effect is less for the wavelengths that enter the horizon at later times, this reduction is stable and permanent.

Keywords: gravitational waves, dark energy, GW's amplitude, all stage universe

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Authors: Igna Brajevic-Gizdic, Magda Pletikosa Pavić

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Introduction: Research in opiate addiction is increasingly indicating the importance of substitution therapy in opiate addicts. Opiate addiction is a chronic relapsing disease that includes craving as a criterion. Craving has been considered a predictor of a relapse, which is defined as a strong desire with an excessive need to take a substance. The study aimed to measure the intensity of craving using the VAS (visual analog scale) in opioid addicts taking Opioid Substitution Therapy (OST). Method: The total sample compromised of 30 participants in outpatient treatment. Two groups of opiate addicts were considered: Methadone-maintenance and buprenorphine-maintenance addicts. The participants completed the survey questionnaire during the outpatient treatment. Results: The results indicated high levels of cravings in patients during the treatment of OST, which is considered an important destabilization factor in abstinence. Thus, the use of methadone/buprenorphine dose should be considered. Conclusion: These findings provided an objective measurement of methadone /buprenorphine dosage and therapy options. The underdoes of OST can put patients at high risk of relapse, resulting in high levels of craving. Thus, when determining the therapeutic dose of OST, it is crucial to consider patients' cravings. This would achieve stabilization more quickly and avoid relapse in abstinence. Subjective physician assessment and patients' statement are the main criteria to determine OST dosage. Future studies should use larger sample sizes and focus on the importance of intensity craving measurement on OST to objectify methadone /buprenorphine dosage.

Keywords: buprenorphine, craving, heroin addicts, methadone, OST

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Authors: Shoroog Alraddadi

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In this study, the effect of gamma irradiation on the structural and transport properties of Bismuth Telluride (Bi₂Te₃) thin films was investigated. Bi₂Te₃ thin films with thicknesses varying from 100 nm to 500 nm were grown using thermal evaporation in vacuum 10⁻⁵ Torr. The films were irradiated by Gamma radiation with different doses (50, 200, and 500 kGy). The crystal structure of Bi₂Te₃ thin films was studied by XRD diffraction. It was showed that the degree of crystallinity of films increases as the doses increase. Furthermore, it was found that the electrical conductivity of Bi₂Te₃ increase as the doses increase. From these results, it can be concluding that the effect of radiation on the structural and transport properties was positive at the levels of irradiation used.

Keywords: bismuth telluride, gamma irradiation, thin film, transport properties

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Authors: C. Elavarasi, T. Shanmuganantham

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A coplanar waveguide (CPW) feed is presented, and comprising a split ring resonator (SRR) loaded fractal with water lily shape is used for multi band applications. The impedance matching of the antenna is determined by the number of Koch curve fractal unit cells. The antenna is designed on a FR4 substrate with a permittivity of ε_{r =} 4.4 and size of 14 x 16 x 1.6 mm³ to generate multi resonant mode at 3.8 GHz covering S band, 8.68 GHz at X band, 13.96 GHz at Ku band, and 19.74 GHz at K band with reflection coefficient better than -10 dB. Simulation results show that the antenna exhibits the desired voltage standing wave ratio (VSWR) level and radiation patterns across the wide frequency range. The fundamental parameters of the antenna such as return loss, VSWR, good radiation pattern with reasonable gain across the operating bands are obtained.

Keywords: fractal, metamaterial, split ring resonator, waterlily shape

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Authors: Zunnu Raen Akhtar, Farhan Ali, Muhammad Saeed-Ur-Rehman

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Jassids are considered as serious sucking pests in eggplants. Jassids can be controlled using imidacloprid, but it can also result in non-target ecological impacts on eco-system. It can also result in reduced population of predators of jassids in the field. An experiment was conducted on jassids, Amrasca sp. reared on eggplant leaves were treated with insecticide imidacloprid at lower, recommended and higher doses including 1L, 2L, 3L respectively. 3rd instar larvae and adults of jassids were exposed to lower, recommended, higher doses. Mortality tests were repeated three times for each dose and insect growth stage. Imidacloprid was sprayed on the leaves followed by drying. Data was recorded for 4, 8, 12, 16, 20, 24 hours after spraying insecticide on the leaves. Results showed that higher mortality was observed in higher and recommended doses, while slow mortality was observed in the case of lower dose. It can be asserted that higher and recommended doses causing immediate mortality of insects are better to control Amrasca sp. in the field, it will not cause immediate resistance development in insects against imidacloprid.

Keywords: Amrasca sp., imidacloprid, egg plant, efficacy

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Authors: Simon Oga Egboja, Agi Sunday

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The government of Nigeria have invested so much in our tertiary education but the desire qualitative goals and objectives are yet to be achieved because management at all level are not efficient and effective in implementing the desired educational policies and programmes due to some management challenges. This paper investigates some of the major challenges to effective management of tertiary institution in Nigeria some variable that are important to effective management includes political stability, adequate funding, establishment of information system, recruitment and appointment of qualified teachers and condition of service.

Keywords: effective management includes political stability, adequate funding, establishment of information system, recruitment and appointment of qualified teachers

Procedia PDF Downloads 296

Authors: Elmo Thiago Lins Cöuras Ford, Valentina Alessandra Carvalho do Vale

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A swimming pool heating system is presented, composed of two alternative collectors with serial PVC absorber tubes that work in regimen of forced stream that is gotten through a bomb. A 500 liters reservoir was used, simulating the swimming pool, being raised some data that show the viability of the considered system. The chosen outflow was corresponding to 100 l/h. In function of the low outflow it was necessary the use of a not popular bomb, choosing the use of a low outflow alternative pumping system, using an air conditioner engine with three different rotations for the desired end. The thermal data related to each collector and their developed system will be presented. The UV and thermal degradations of the PVC exposed to solar radiation will be also boarded, demonstrating the viability of using tubes of this material as absorber elements of radiation in water heating solar collectors.

Keywords: solar energy, solar swimming pool, water heating, PVC tubes, alternative system

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Authors: Omid Ghollipoor Bashiri, Farzam Hatefi

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Dichlorvos a synthetic organophosphate poisons are used as insecticide. These toxins can be used insecticides in agriculture and medicine for destruction and/or eradication of ectoparasites of animals. Studies have shown that Dichlorvos creation seizure effects in different animals. Amlodipine, dihydropyridine calcium channel blockers, widely used for treatment of cardiovascular diseases. Studies have shown that the calcium channel blockers are anticonvulsant effects in different animal models. The aim of this study was to determine the effect of Amlodipine on Dichlorvos-induced seizures in mice. In this experiment, the animals were received different doses of Amlodipine (2.5, 5, 10, 20 and 40 mg/ kg b.wt.) intraperitoneally 30 min before intraperitoneal injection of Dichlorvos (50 mg/kg b.wt). After Dichlorvos injection, clonic and tonic seizures, and finally was the fate was investigated. Results showed that Amlodipine dose-dependently reduced the severity of Dichlorvos-induced seizures, so that Amlodipine at a dose of 5mg (The lowest, p<0.05) and 40 mg/kg b.wt. (The highest, p<0.001) which had anticonvulsant effects. The anticonvulsant activity of Amlodipine suggests that possibly due to the antagonistic effect on voltage-dependent calcium channel.

Keywords: dichlorvos, amlodipine, seizures, mice

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Authors: A. Goma Amira, U. E. Mahrous

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Measuring the effect of perinatal lead exposure on learning ability of offspring is considered as a sensitive and selective index for providing an early marker for central nervous system damage produced by this toxic metal. A total of 35 Sprague-Dawley adult rats were used to investigate the effect of lead acetate toxicity on behavioral patterns of adult female rats and learning ability of offspring. Rats were allotted into 4 groups, group one received 1g/l lead acetate (n=10), group two received 1.5g/l lead acetate (n=10), group three received 2g/l lead acetate in drinking water (n=10), and control group did not receive lead acetate (n=5) from 8th day of pregnancy till weaning of pups. The obtained results revealed a dose-dependent increase in the feeding time, drinking frequency, licking frequency, scratching frequency, licking litters, nest building, and retrieving frequencies, while standing time increased significantly in rats treated with 1.5g/l lead acetate than other treated groups and control. On the contrary, lying time decreased gradually in a dose-dependent manner. Moreover, movement activities were higher in rats treated with 1g/l lead acetate than other treated groups and control. Furthermore, time spent in closed arms was significantly lower in rats given 2g/l lead acetate than other treated groups, while they spent significantly much time spent in open arms than other treated groups which could be attributed to occurrence of adaptation. Furthermore, number of entries in open arms was-dose dependent. However, the ratio between open/closed arms revealed a significant decrease in rats treated with 2g/l lead acetate than the control group.

Keywords: lead toxicity, rats, learning ability, behavior

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Authors: Petar Sarajcev, Josip Vasilj, Damir Jakus

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This paper presents a novel statistical description of the counterpoise effective length due to lightning surges, where the (impulse) effective length had been obtained by means of regressive formulas applied to the transient simulation results. The effective length is described in terms of a statistical distribution function, from which median, mean, variance, and other parameters of interest could be readily obtained. The influence of lightning current amplitude, lightning front duration, and soil resistivity on the effective length has been accounted for, assuming statistical nature of these parameters. A method for determining the optimal counterpoise length, in terms of the statistical impulse effective length, is also presented. It is based on estimating the number of dangerous events associated with lightning strikes. Proposed statistical description and the associated method provide valuable information which could aid the design engineer in optimising physical lengths of counterpoises in different grounding arrangements and soil resistivity situations.

Keywords: counterpoise, grounding conductor, effective length, lightning, Monte Carlo method, statistical distribution

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Authors: Pui Hong Chung, Wing Chi Ho, Jun Li, Cyrus Leung, Ek Yeoh

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Background: Cigarette smoking is associated with poor tuberculosis (TB) outcomes in terms of progression of active TB, relapse of TB and TB-related mortality, but the association with latent tuberculosis infection (LTBI) is unclear. The systematic review conducted aimed at studying the association between active smoking and LTBI, and likelihood of dose-response relationship. Methods: Two independent reviewers searched three electronic databases comprising PudMed, Medline by EBSCOHOST, ExcerptaMedica Database (EMBASE), from inception up to 31st Dec 2015 for studies reporting data on current smoking and the LTBI with tuberculin skin test (TST) or interferon-γ release assays (IGRAs) results, comparing the odds ratios (ORs) of outcome measure of TST or IGRAs among current smokers with 95% confidence intervals (CI). Results: Seven studies were identified, including six cross-sectional studies and one longitudinal cohort study. The outcome measures from three studies were in TST, three studies in IGRAs and one for both tests. For TST, OR ranging from 1.39 to 3.40 (95% CI) with all studies shown positive association between cigarette smoking and LTBI. For IGRAs, OR ranging from 0.47 to 1.89 (95% CI) with one study shown the negative association that might be related to impaired interferon-gamma production in immunosuppressive persons. One identified study demonstrated positive dose-response relationship in TST result. Conclusions: Cigarette smoking is likely to be a risk factor of LTBI. There is the important implication for TB and tobacco control program to halt TB by empowering public health policy. Further study is also needed to provide more evidence of the dose-response model/relationship.

Keywords: latent tuberculosis infection, systematic review, active smoking, model

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Authors: Ouardi Okkacha, Kaarour Abedlkrim, Meskine Mohamed

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The effective Hamiltonians are widely used in molecular spectroscopy for the interpretation of the vibration-rotation spectra. Their construction is an ambiguous procedure due to the existence of unitary transformations that change the effective Hamiltonian but do not change its eigenvalues. As a consequence of this ambiguity, it may happen that some parameters of effective Hamiltonians cannot be recovered from experimental data in a unique way. The type of admissible transformations which keeps the operator form of the effective Hamiltonian unaltered and the number of empirically determinable parameters strongly depend on the symmetry type of a molecule (asymmetric top, spherical top, and so on) and on the degeneracy of the vibrational state. In this work, we report the study of the ambiguity of effective Hamiltonian for the fundamental degenerate states v3 of the Molecule 12CD4.

Keywords: 12CD4, high-resolution infrared spectra, tetrahedral tensorial formalism, vibrational states, rovibrational line position analysis, XTDS, SPVIEW

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Authors: Ranojoy Dutta

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HVAC equipment capacity has a direct impact on occupant comfort and energy consumption of a building. Glazing gains, especially in buildings with high window area, can be a significant contributor to the total peak load on the HVAC system, leading to over-sized systems that mostly operate at poor part load efficiency. In addition, radiant temperature, which largely drives occupant comfort in glazed perimeter zones, is often not effectively controlled despite the HVAC being designed to meet the air temperature set-point. This is due to short wave solar radiation transmitted through windows, that is not sensed by the thermostat until much later when the thermal mass in the room releases the absorbed solar heat to the indoor air. The implication of this phenomenon is increased cooling energy despite poor occupant comfort. EC glazing can significantly eliminate direct solar transmission through windows, reducing both the space cooling loads for the building and improving comfort for occupants near glazing. This paper will review the exact mechanism of how EC glazing would reduce the peak load under design day conditions, leading to reduced cooling capacity vs regular high-performance glazing. Since glazing heat transfer only affects the sensible load, system sizing will be evaluated both with and without the availability of a DOAS to isolate the downsizing potential of the primary cooling equipment when outdoor air is conditioned separately. Given the dynamic nature of glazing gains due to the sun’s movement, effective peak load mitigation with EC requires an automated control system that can predict solar movement and radiation levels so that the right tint state with the appropriate SHGC is utilized at any given time for a given façade orientation. Such an automated EC product will be evaluated for a prototype commercial office model situated in four distinct climate zones.

Keywords: electrochromic glazing, peak sizing, thermal comfort, glazing load

Procedia PDF Downloads 126

Authors: B. Petrović, L. Rutonjski, M. Baucal, M. Teodorović, O. Čudić, B. Basarić

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Purpose/Objective: Radiotherapy treatment planning requires use of CT simulator, in order to acquire CT images. The overall performance of CT simulator determines the quality of radiotherapy treatment plan, and at the end, the outcome of treatment for every single patient. Therefore, it is strongly advised by international recommendations, to set up a quality control procedures for every machine involved in radiotherapy treatment planning process, including the CT scanner/ simulator. The overall process requires number of tests, which are used on daily, weekly, monthly or yearly basis, depending on the feature tested. Materials/Methods: Two phantoms were used: a dedicated phantom CIRS 062QA, and a QA phantom obtained with the CT simulator. The examined CT simulator was Siemens Somatom Definition as Open, dedicated for radiation therapy treatment planning. The CT simulator has a built in software, which enables fast and simple evaluation of CT QA parameters, using the phantom provided with the CT simulator. On the other hand, recommendations contain additional test, which were done with the CIRS phantom. Also, legislation on ionizing radiation protection requires CT testing in defined periods of time. Taking into account the requirements of law, built in tests of a CT simulator, and international recommendations, the intitutional QC programme for CT imulator is defined, and implemented. Results: The CT simulator parameters evaluated through the study were following: CT number accuracy, field uniformity, complete CT to ED conversion curve, spatial and contrast resolution, image noise, slice thickness, and patient table stability.The following limits are established and implemented: CT number accuracy limits are +/- 5 HU of the value at the comissioning. Field uniformity: +/- 10 HU in selected ROIs. Complete CT to ED curve for each tube voltage must comply with the curve obtained at comissioning, with deviations of not more than 5%. Spatial and contrast resultion tests must comply with the tests obtained at comissioning, otherwise machine requires service. Result of image noise test must fall within the limit of 20% difference of the base value. Slice thickness must meet manufacturer specifications, and patient stability with longitudinal transfer of loaded table must not differ of more than 2mm vertical deviation. Conclusion: The implemented QA tests gave overall basic understanding of CT simulator functionality and its clinical effectiveness in radiation treatment planning. The legal requirement to the clinic is to set up it’s own QA programme, with minimum testing, but it remains user’s decision whether additional testing, as recommended by international organizations, will be implemented, so to improve the overall quality of radiation treatment planning procedure, as the CT image quality used for radiation treatment planning, influences the delineation of a tumor and calculation accuracy of treatment planning system, and finally delivery of radiation treatment to a patient.

Keywords: CT simulator, radiotherapy, quality control, QA programme

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Authors: Jia-Jia He, Lin Jiang, Jin-Hua Sun

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Rigid polyurethane foam (RPU) has been extensively applied in building insulation system, yet with high flammability for being easily ignited by high temperature spark or radiative heat flux from other flaming materials or surrounding building facade. Using a cone calorimeter by Fire Testing Technology and thermal couple tree, this study systematically investigated the effect of radiative heat flux on the ignition time and characteristic temperature distribution during RPU combustion under different heat fluxes gradient (12, 15, 20, 25, 30, 35, 40, 45, and 50 kW/m²) with spark ignition/ignition by radiation. The ignition time decreases proportionally with increase of external heat flux, meanwhile increasing the external heat flux raises the peak heat release rate and impresses on the vertical temperature distribution greatly. The critical ignition heat flux is found to be 15 and 25 kW/m² for spark ignition and radiative ignition, respectively. Based on previous experienced ignition formula, a methodology to predict ignition times in both modes has been developed theoretically. By analyzing the heat transfer mechanism around the sample surroundings, both radiation from cone calorimeter and convection flow are considered and calculated theoretically. The experimental ignition times agree well with the theoretical ones in both radiative and convective conditions; however, the observed critical ignition heat flux is higher than the calculated one under piloted-ignition mode because the heat loss process, especially in lower heat flux radiation, is not considered in this developed methodology.

Keywords: rigid polyurethane foam, cone calorimeter, ignition time, external heat flux

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Authors: Khanom Simarani

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Rice husk has been widely reported as a good sorbent for heavy metals. Pre treatment of rice husk minimizes cellulose crystallinity and increases the surface area thus ensuring better adsorption capacity. Commercial base and natural base-treated rice husk were used to investigate the potential of Ni(II) adsorption from synthetic solutions and waste water in batch systems. Effects of process variables such as pH, contact time, adsorbent dose, initial Ni (II) concentration were studied. Optimum Ni (II) adsorption was observed at pH 6 within 60 min of contact time. Experimental data showed increased amount of adsorbed Ni(II) with increasing adsorbent dose and decreased percent of adsorption with increasing initial Ni(II) concentration. Kinetic isotherms (Langmuir, Freundlich) were also applied. Biosorption mechanism of rice husk was analyzed using SEM/EDS, FT-IR, and XRD. The results revealed that natural base produced from agroindustrial waste could be used as efficient as commercial bases during pre treatment rice husk in removing Ni(II) from waste waters within 15 min.

Keywords: Nickel removal, adsorbent, heavy metal, biomass

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Authors: R. Hasan

Abstract:

Male factor infertility due to endocrine disturbances such as abnormalities in prolactin levels are encountered in a significant proportion. This case control study was carried out to determine the effects of prolactin on the male reproductive tract, using 200 male white rats. The rats were maintained as the control group (G1), hypoprolactinaemic group (G2), 3 hyperprolactinaemic groups induced using oral largactil (G3), low dose fluphenazine (G4) and high dose fluphenazine (G5). After 100 days, rats were subjected to serum prolactin (PRL) level measurements and for basic seminal fluid analysis (BSA). The difference between serum PRL concentrations of rats in G2, G3, G4 and G5 as compared to the control group were highly significant by Student’s t-test (p<0.001). There were statistically significant differences in seminal fluid characteristics of rats with induced prolactin abnormalities when compared with those of control group (p value <0.05), effects were more marked as the PRL levels rise.

Keywords: male factor infertility, prolactin, seminal fluid analysis, animal studies

Procedia PDF Downloads 287

Authors: Manpreet Kaur

Abstract:

The effect of external and internal exposure in outdoor and indoor environment can be significantly gauged by natural radionuclides. Therefore, it is a consequential to approximate the level of radionuclide contents in soil samples of any area and the risks associated with it. Rate of radon emerging from soil is also one of the prominent parameters for the assessment of radon levels in environmental. In present study, natural radionuclide contents viz. ²³²Th, ²³⁸U and ⁴⁰K and radon/thoron exhalation rates were evaluated operating thallium doped sodium iodide gamma radiation detector and advanced Smart Rn Duo technique in the soil samples from 30 villages of Jammu district, Jammu and Kashmir, India. Radon flux rate was also measured by using surface chamber technique. Results obtained with two different methods were compared to investigate the cause of emanation factor in the soil profile. The radon mass exhalation rate in the soil samples has been found varying from 15 ± 0.4 to 38 ± 0.8 mBq kg⁻¹ h⁻¹ while thoron surface exhalation rate has been found varying from 90 ± 22 to 4880 ± 280 Bq m⁻² h⁻¹. The mean value of radium equivalent activity (99 ± 27 Bq kg⁻¹) was appeared to be well within the admissible limit of 370 Bq kg⁻¹ suggested by Organization for Economic Cooperation and Development (2009) report. The values of various parameters related to radiological hazards were also calculated and all parameters have been found to be well below the safe limits given by various organizations. The outcomes pointed out that region was protected from danger as per health risks effects associated with these radionuclide contents is concerned.

Keywords: absorbed dose rate, exhalation rate, human health, radionuclide

Procedia PDF Downloads 133

Authors: Rajasekar Elangopandian, Anand Shanmugam

Abstract:

Now-a-days for surveillances unmanned aerial vehicle plays a vital role. Not only for surveillances, aerial photography disaster management and the notice of earth behavior UAV1s envisages meticulously. To reduce the maintenance and fuel nuclear powered Vehicles are greater support. The design consideration is much important for the UAV manufacturing industry and Research and development agency. Eventually design is looking like a pentagon shaped fuselage and black rubber coated paint in order to escape from the enemy radar and other targets. The pentagon shape fuselage has large space to keep the mini nuclear reactor inside and the material is carbon – carbon fiber specially designed by the software called cosmol and hyper mesh 14.2. So the weight consideration will produce the positive result for productivity. The walls of the fuselage are coated with lead and protective shield. A double layer of W/Bi sheet is proposed for radiation protection at the energy range of 70 Kev to 90 Kev. The designed W/bi sheet, only 0.14 mm thick and is 36% light. The properties of the fillers were determined from zeta potential and particle size measurements. The Exposes of the radiation can be attenuated by 3 ways such as minimizing exposure time, Maximizing distance from the radiation source and shielding the whole vehicle. The inside reactor will be switched ON when the UAV starts its cruise. The moderators and the control rods can be inserted by automation technique by newly developed software. The heat generated by the reactor will be used to run the turbine which is fixed inside the UAV called mini turbine with natural rubber composite Shaft radiation shield. Cooling system will be in two mode such as liquid and air cooled. Liquid coolant for the heat regeneration is ordinary water, liquid sodium, helium and the walls are made up of regenerative and radiation protective material. The other components like camera and arms bay will be located at the bottom of the UAV high are specially made products in order to escape from the radiation. They are coated with lead Pb and natural rubber composite material. This technique provides the long rang and endurance for eternal flight mission until we need any changeability of parts or product. This UAV has the special advantage of ` land on String` means it`ll land at electric line to charge the automated electronics. Then the fuel is enriched uranium (< 5% U - 235) contains hundreds of fuel pins. This technique provides eternal duty for surveillances and aerial photography. The landing of the vehicle is ease of operation likewise the takeoff is also easier than any other mechanism which present in nowadays. This UAV gives great immense and immaculate technology for surveillance and target detecting and smashing the target.

Keywords: mini turbine, liquid coolant for the heat regeneration, in order to escape from the radiation, eternal flight mission, it`ll land at electric line

Procedia PDF Downloads 408

Authors: Ajuna B. Henry

Abstract:

In recent decades, climate change has demanded biological pesticides; more Bt strains are being discovered worldwide, some containing novel insecticidal genes while others have been modified through molecular approaches for increased yield, toxicity, and wider host target. In this study, B. thuringiensis strain AH-2 (Bt-2) was isolated from the soil and tested for insecticidal activity against Aphis gossypii (Hemiptera: Aphididae) and Lepidoptera insect pests: fall webworm (Hyphantria cunea) and diamondback moth (Plutella xylostella). A commercial strain B. thuringiensis subsp. kurstaki (Btk), and a chemical pesticide, imidacloprid (for Hemiptera) and chlorantraniliprole (for Lepidoptera), were used as positive control and the same media (without bacterial inoculum) as a negative control. For aphidicidal activity, Bt-2 caused a mortality rate of 70.2%, 78.1% or 88.4% in third instar nymphs of A. gossypii (3N) at 10%, 25% or 50% culture concentrations, respectively. Moreover, Bt-2 was effectively produced in cost-effective (PB) supplemented with either glucose (PBG) or sucrose (PBS) and maintained high aphicidal efficacy with 3N mortality rates of 85.9%, 82.9% or 82.2% in TSB, PBG or PBS media, respectively at 50% culture concentration. Bt-2 also suppressed adult fecundity by 98.3% compared to only 65.8% suppression by Btk at similar concentrations but was slightly lower than chemical treatment, which caused 100% suppression. Partial purification of 60 – 80% (NH4)2SO4 fraction of Bt-2 aphicidal proteins purified on anion exchange (DEAE-FF) column revealed a 105 kDa aphicidal protein with LC50 = 55.0 ng/µℓ. For Lepidoptera pests, chemical pesticide, Bt-2, and Btk cultures, mortality of 86.7%, 60%, and 60% in 3rd instar larvae of P. xylostella, and 96.7%, 80.0%, and 93.3% in 6th instar larvae of H. cunea, after 72h of exposure. When the entomopathogenic strains were cultured in a cost-effective PBG or PBS, the insecticidal activity in all strains was not significantly different compared to the use of a commercial medium (TSB). Bt-2 caused a mortality rate of 60.0%, 63.3%, and 50.0% against P. xylostella larvae and 76.7%, 83.3%, and 73.3% against H. cunea when grown in TSB, PBG, and PBS media, respectively. Bt-2 (grown in cost-effective PBG medium) caused a dose-dependent toxicity of 26.7%, 40.0%, and 63.3% against P. xylostella and 46.7%, 53.3%, and 76.7% against H. cunea at 10%, 25% and 50% culture concentration, respectively. The partially purified Bt-2 insecticidal proteins fractions F1, F2, F3, and F4 (extracted at different ratios of organic solvent) caused low toxicity (50.0%, 40.0%, 36.7%, and 30.0%) against P. xylostella and relatively high toxicity (56.7%, 76.7%, 66.7%, and 63.3%) against H. cunea at 100 µg/g of artificial diets. SDS-PAGE analysis revealed that a128kDa protein is associated with toxicity of Bt-2. Our result demonstrates a medium and strong larvicidal activity of Bt-2 against P. xylostella and H. cunea, respectively. Moreover, Bt-2 could be potentially produced using a cost-effective PBG medium which makes it an effective alternative biocontrol strategy to reduce chemical pesticide application.

Keywords: biocontrol, insect pests, larvae/nymph mortality, cost-effective media, aphis gossypii, plutella xylostella, hyphantria cunea, bacillus thuringiensi

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Authors: Emre Ünal, Hasan Başaran

Abstract:

In this study, starting with a predetermined Lunar free-return trajectory, an analysis of major near-Earth perturbations is carried out. Referencing to historical Apollo-13 flight, changes in the mission’s resultant perimoon and perigee altitudes with each perturbative effect are evaluated. The perturbations that were considered are Earth oblateness effects, up to the 6^th order, atmospheric drag, third body perturbations consisting of solar and planetary effects and solar radiation pressure effects. It is found that for a Moon mission, most of the main perturbative effects spoil the trajectory significantly while some came out to be negligible. It is seen that for apparent future request of constructing low cost, reliable and safe trajectories to the Moon, most of the orbital perturbations are crucial.

Keywords: Apollo-13 trajectory, atmospheric drag, lunar trajectories, oblateness effect, perturbative effects, solar radiation pressure, third body perturbations

Procedia PDF Downloads 142

Authors: Farah Ali, Tehreem Fayyaz, Musadiq Idris

Abstract:

The present work was undertaken to investigate effects of various extracts of W. somniferafor anti-diabetic activity in alloxan induced diabetic rabbits. Rabbits were acclimatized for a week to standard laboratory temperature. Animals were fed according to a strict schedule (8 am, 3 pm and 10 pm) with green fodder (Medicago sativa) and tap water ad libitum. Animals were divided into nine groups of six rabbits each in a random manner. Body weights and physical activities of all rabbits were recorded before start of experiments. The animals of group 1 and 2 were given lactose (250 mg/kg,p.o) and Withaniasomniferaroot powder (100 mg/kg, p.o) respectively daily from day 1-20. Animals of group 3 were given alloxan (100 mg/kg,i.v) as a single dose on day 1. Powdered root of Withaniasomnifera in the doses of 100, 150, 200 mg/kg and its aqueous and ethanol extracts (equivalent to 200 mg/kg of crude drug) were given to the treated animals (groups 4-8), respectively by oral route for three weeks (day 1-20o.d), along with alloxan (100 mg/kg, i.v) as a single dose on day 1. Group 9 was treated with metformin (200 mg/kg, p.o) daily from day 1-20, along with a single dose of alloxan (100 mg/ kg, i.v) on day 1. Fasting serum glucose concentration in groups 3-9 was increased significantly (p<0.05) on day 3, with a maximum increase (215.3 mg/dl) in animals of toxic control (TC) group (3) on day 21 of the experiment as compared to normal control (NC) group (1). Effects of different doses (100, 150, 200 mg/kg, p.o) of W. somnifera root powder (WS) decreased the fasting serum glucose concentration as compared to toxic control group, with a maximum decrease (88.3 mg/dl) in group 2 (treated control) on day 21 of the experiment. Metformin (200 mg/kg, p.o) (reference control), aqueous extract (AWS) and ethanol extract (EWS) of W. somnifera (equivalent to 100 mg/kg W.somnifera root, p.o) antagonized the effects of alloxan as compared to toxic control group. These results indicate that the W. somnifera possess significant anti –diabetic activity.

Keywords: diabetes, serum, glucose, blood, sugar, rabbits

Procedia PDF Downloads 560

Authors: Liangliang Tang, Chang Xu, Xingying Chen

Abstract:

GaInAsSb cells probably show better performance than GaSb cells in low-temperature thermophotovoltaic systems due to lower bandgap; however, few experiments proved this phenomenon so far. In this paper, numerical simulation is used to evaluate GaInAsSb and GaSb cells with similar structures under different radiation temperatures. We found that GaInAsSb cells with n-type emitters show slightly higher output power densities compared with that of GaSb cells with n-type emitters below 1,550 K-blackbody radiation, and the power density of the later cells will suppress the formers above this temperature point. During the temperature range of 1,000~2,000 K, the efficiencies of GaSb cells are about twice of GaInAsSb cells if perfect filters are used to prevent the emission of the non-absorbed long wavelength photons. Several parameters that affect the GaInAsSb cell were analyzed, such as doping profiles, thicknesses of GaInAsSb epitaxial layer and surface recombination velocity. The non-p junctions, i.e., n-type emitters are better for GaInAsSb cell fabrication, which is similar to that of GaSb cells.

Keywords: thermophotovoltaic cell, GaSb, GaInAsSb, diffused emitters

Procedia PDF Downloads 276