Search results for: Lens esculenta
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 524

Search results for: Lens esculenta

524 Evaluation of Antioxidant Activity and Total Phenolic Content of Lens Esculenta Moench, Seeds

Authors: Vivek Kumar Gupta, Kripi Vohra, Monika Gupta

Abstract:

Pulses have been a vital ingredient of the balanced human diet in India. Lentil (Lens culinaris Medikus or Lens esculenta Moench.) is a common legume known since biblical times. Lentil seeds, with or without hulls, are cooked as dhal and this has been the main dish for millennia in the South Asian region. Oxidative stress can damage lipids, proteins, enzymes, carbohydrates and DNA in cells and tissues, resulting in membrane damage, fragmentation or random cross linking of molecules like DNA, enzymes and structural proteins and even lead to cell death induced by DNA fragmentation and lipid peroxidation. These consequences of oxidative stress construct the molecular basis in the development of cancer, neurodegenerative disorders, cardiovascular diseases, diabetes and autoimmune. The aim of the present work is to assess the antioxidant potential of the peteroleum ether, acetone, methanol and water extract of the Lens esculenta seeds. In vitro antioxidant assessment of the extracts was carried out using 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activity, hydroxyl radical scavenging activity, reducing power assay. The quantitative estimation of total phenolic content, total flavonoid content in extracts and in plant material, total saponin content, total alkaloid content, crude fibre content, total volatile content, fat content and mucilage content in drug material was also carried out. Though all the extracts exhibited dose dependent reducing power activity the acetone extract was found to possess significant hydrogen donating ability in DPPH (45.83%-93.13%) and hydroxyl radical scavenging system (28.7%-46.41%) than the peteroleum ether, methanol and water extracts. Total phenolic content in the acetone and methanol extract was found to be 608 and 188 mg gallic acid equivalent of phenol/g of sample respectively. Total flavonoid content of acetone and methanol extract was found to be 128 and 30.6 mg quercetin equivalent/g of sample respectively. It is evident that acetone extract of Lentil seeds possess high levels of polyphenolics and flavonoids that could be utilized as antioxidants and neutraceuticals.

Keywords: antioxidant, flavanoids, Lens esculenta, polyphenols

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523 Using Divergent Nozzle with Aerodynamic Lens to Focus Nanoparticles

Authors: Hasan Jumaah Mrayeh, Fue-Sang Lien

Abstract:

ANSYS Fluent will be used to simulate Computational Fluid Dynamics (CFD) for an efficient lens and nozzle design which will be explained in this paper. We have designed and characterized an aerodynamic lens and a divergent nozzle for focusing flow that transmits sub 25 nm particles through the aerodynamic lens. The design of the lens and nozzle has been improved using CFD for particle trajectories. We obtained a case for calculating nanoparticles (25 nm) flowing through the aerodynamic lens and divergent nozzle. Nanoparticles are transported by air, which is pumped into the aerodynamic lens through the nozzle at 1 atmospheric pressure. We have also developed a computational methodology that can determine the exact focus characteristics of aerodynamic lens systems. Particle trajectories were traced using the Lagrange approach. The simulation shows the ability of the aerodynamic lens to focus on 25 nm particles after using a divergent nozzle.

Keywords: aerodynamic lens, divergent nozzle, ANSYS Fluent, Lagrange approach

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522 The Effect of Combined Doxorubicin and Dioscorea esculenta on Apoptosis Induction in Human Breast Cancer Cells

Authors: Dina Fatmawati, Sofia Mubarika, Mae Sri Wahyuningsih

Abstract:

Chemotherapy for breast cancer is largely ineffective, but innovative combinations of chemotherapeutic agents and natural compounds represent a promising strategy. In our previous study, the combination of Doxorubicin (Dox) and ethanolic extract of Dioscorea esculenta tuber ((EED) was found to have a synergistic effect on T47D human breast cancer cell line. In this study, we investigated the apoptotic effect of the combination on T47D human breast cancer cells and normal fibroblasts cell line and its effects on the expression of Caspase-3 and cleaved poly (ADP-Ribose) Polymerase-1 (cPARP-1) protein. T47D cell lines and fibroblasts cells were treated with the combination of Dox and EED. Apoptotic effect of the combination was determined using flow cytrometry assay. Protein expressions were determined by immunocytochemistry staining. The percentage of apoptotic cells were significantly higher in T47D cell lines (75%) than that of in fibroblast cells (23%). The expression of Caspase 3 (84.53%) and cPARP-1 (83.36%) were significantly higher in the cancer cell lines than those of normal cells. These results indicate that the combination of doxorubicin and Dioscorea esculenta is a promising candidate for the treatment of breast cancer cells.

Keywords: Dioscorea esculenta, Doxorubicin, apoptosis, immunocytochemistry, cancer cells

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521 Phytochemical Analysis and Antioxidant Activity of Colocasia esculenta (L.) Leaves

Authors: Amit Keshav, Alok Sharma, Bidyut Mazumdar

Abstract:

Colocasia esculenta leaves and roots are widely used in Asian countries, such as, India, Srilanka and Pakistan, as food and feed material. The root is high in carbohydrates and rich in zinc. The leaves and stalks are often traditionally preserved to be eaten in dry season. Leaf juice is stimulant, expectorant, astringent, appetizer, and otalgia. Looking at the medicinal uses of the plant leaves; phytochemicals were extracted from the plant leaves and were characterized using Fourier-transform infrared spectroscopy (FTIR) to find the functional groups. Phytochemical analysis of Colocasia esculenta (L.) leaf was studied using three solvents (methanol, chloroform, and ethanol) with soxhlet apparatus. Powder of the leaves was employed to obtain the extracts, which was qualitatively and quantitatively analyzed for phytochemical content using standard methods. Phytochemical constituents were abundant in the leave extract. Leaf was found to have various phytochemicals such as alkaloids, glycosides, flavonoids, terpenoids, saponins, oxalates and phenols etc., which could have lot of medicinal benefits such as reducing headache, treatment of congestive heart failure, prevent oxidative cell damage etc. These phytochemicals were identified using UV spectrophotometer and results were presented. In order to find the antioxidant activity of the extract, DPPH (2,2-diphenyl-1-picrylhydrazyl) method was employed using ascorbic acid as standard. DPPH scavenging activity of ascorbic acid was found to be 84%, whereas for ethanol it was observed to be 78.92%, for methanol: 76.46% and for chloroform: 72.46%. Looking at the high antioxidant activity, Colocasia esculenta may be recommended for medicinal applications. The characterizations of functional groups were analyzed using FTIR spectroscopy.

Keywords: antioxidant activity, Colocasia esculenta, leaves, characterization, FTIR

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520 Complications of Contact Lens-Associated Keratitis: A Refresher for Emergency Departments

Authors: S. Selman, T. Gout

Abstract:

Microbial keratitis is a serious complication of contact lens wear that can be vision and eye-threatening. Diverse presentations relating to contact lens wear include dry corneal surface, corneal infiltrate, ulceration, scarring, and complete corneal melt leading to perforation. Contact lens wear is a major risk factor and, as such, is an important consideration in any patient presenting with a red eye in the primary care setting. This paper aims to provide an overview of the risk factors, common organisms, and spectrum of contact lens-associated keratitis (CLAK) complications. It will highlight some of the salient points relevant to the assessment and workup of patients suspected of CLAK in the emergency department based on the recent literature and therapeutic guidelines. An overview of the management principles will also be provided.

Keywords: microbial keratitis, corneal pathology, contact lens-associated complications, painful vision loss

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519 Assessment of Heavy Metal Bioaccumulation by Tissues of Ipomoea Batatas and Manihot Esculenta Irrigated with Water from Muhammad Ayuba Dam, Kazaure, Jigawa State, Nigeria

Authors: Sa’idu A. Abdullah, Jafar Lawan, A. U. Adamu, Fowotade, S. A., Hamisu Abdu

Abstract:

Scarcity of quality water in many communities compels inhabitants to use any available water resources for domestic, recreational, industrial and agricultural purposes. Global concern on the potential health hazards of anthropogenic inputs into our ecosystems imposes the need for constant monitoring of levels of pollutants in order to ensure compliance with internationally acceptable criteria. In this research, assessment of bioaccumulation of Cd, Co, Cu, Pb and Zn was carried out using tissues of Ipomoea batatas (sweet potato) and Manihot esculenta (cassava) irrigated with water from Muhammad Ayuba Dam in Kazaure, Jigawa State. The metal concentrations were determined using Flame Atomic Absorption Spectrophotometer (FAAS). The result of the analysis revealed the presence of the metals in varying concentrations. Cd and Co showed higher concentrations in the tubers of Manihot esculenta but all the other investigated metals were more concentrated in the leaves of the plant. Cd and Cu on the other hand showed higher concentration in the root of Ipomoea batatas while the remaining investigated metals were concentrated more in the leaves of the plant. The result of analysis of water samples from five sampling stations in the Dam showed the presence of the metals as follows: Cd, (0.063±0.02 mg/L), Co (0.086±0.03 mg/L), Cu (0.167±0.08 mg/L), Pb (0.22±0.01 mg/L) and Zn (0.047±0.01 mg/L) respectively. The results of bioaccumulation studies using the Bioaccumulation Factors (BAF) index indicated Ipomoea batatas to have higher bioaccumulation potential for Cd, Co and Cu while Pb and Zn were more accumulated in Manihot esculenta. The levels of the metals in both the water samples and plant tissues were all below the WHO permissible limit. This is indicative that the inhabitants of the community under investigation are not at any health risk.

Keywords: agriculture, bioaccumulation, heavy metal, plant tissues

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518 Parameters Influencing the Output Precision of a Lens-Lens Beam Generator Solar Concentrator

Authors: M. Tawfik, X. Tonnellier, C. Sansom

Abstract:

The Lens-Lens Beam Generator (LLBG) is a Fresnel-based optical concentrating technique which provides flexibility in selecting the solar receiver location compared to conventional techniques through generating a powerful concentrated collimated solar beam. In order to achieve that, two successive lenses are used and followed by a flat mirror. Hence the generated beam emerging from the LLBG has a high power flux which impinges on the target receiver, it is important to determine the precision of the system output. In this present work, mathematical investigation of different parameters affecting the precision of the output beam is carried out. These parameters include: Deflection in sun-facing lens and its holding arm, delay in updating the solar tracking system, and the flat mirror surface flatness. Moreover, relationships that describe the power lost due to the effect of each parameter are derived in this study.

Keywords: Fresnel lens, LLBG, solar concentrator, solar tracking

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517 Human Lens Metabolome: A Combined LC-MS and NMR Study

Authors: Vadim V. Yanshole, Lyudmila V. Yanshole, Alexey S. Kiryutin, Timofey D. Verkhovod, Yuri P. Tsentalovich

Abstract:

Cataract, or clouding of the eye lens, is the leading cause of vision impairment in the world. The lens tissue have very specific structure: It does not have vascular system, the lens proteins – crystallins – do not turnover throughout lifespan. The protection of lens proteins is provided by the metabolites which diffuse inside the lens from the aqueous humor or synthesized in the lens epithelial layer. Therefore, the study of changes in the metabolite composition of a cataractous lens as compared to a normal lens may elucidate the possible mechanisms of the cataract formation. Quantitative metabolomic profiles of normal and cataractous human lenses were obtained with the combined use of high-frequency nuclear magnetic resonance (NMR) and ion-pairing high-performance liquid chromatography with high-resolution mass-spectrometric detection (LC-MS) methods. The quantitative content of more than fifty metabolites has been determined in this work for normal aged and cataractous human lenses. The most abundant metabolites in the normal lens are myo-inositol, lactate, creatine, glutathione, glutamate, and glucose. For the majority of metabolites, their levels in the lens cortex and nucleus are similar, with the few exceptions including antioxidants and UV filters: The concentrations of glutathione, ascorbate and NAD in the lens nucleus decrease as compared to the cortex, while the levels of the secondary UV filters formed from primary UV filters in redox processes increase. That confirms that the lens core is metabolically inert, and the metabolic activity in the lens nucleus is mostly restricted by protection from the oxidative stress caused by UV irradiation, UV filter spontaneous decomposition, or other factors. It was found that the metabolomic composition of normal and age-matched cataractous human lenses differ significantly. The content of the most important metabolites – antioxidants, UV filters, and osmolytes – in the cataractous nucleus is at least ten fold lower than in the normal nucleus. One may suppose that the majority of these metabolites are synthesized in the lens epithelial layer, and that age-related cataractogenesis might originate from the dysfunction of the lens epithelial cells. Comprehensive quantitative metabolic profiles of the human eye lens have been acquired for the first time. The obtained data can be used for the analysis of changes in the lens chemical composition occurring with age and with the cataract development.

Keywords: cataract, lens, NMR, LC-MS, metabolome

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516 Biochemical Efficacy, Molecular Docking and Inhibitory Effect of 2,3-Dimethylmaleic Anhydride on Acetylcholinesterases

Authors: Kabrambam D. Singh, Dinabandhu Sahoo, Yallappa Rajashekar

Abstract:

Evolution has caused many insects to develop resistance to several synthetic insecticides. This problem along with the persisting concern regarding the health and environmental safety issues of the existing synthetic insecticides has urged the scientific fraternity to look for a new plant-based natural insecticide with inherent eco-friendly nature. Colocasia esculenta var. esculenta (L.) Schott (Araceae family) is widely grown throughout the South- East Asian Countries for its edible corms and leaves. Various physico-chemical and spectroscopic techniques (IR, 1H NMR, 13C NMR and Mass) were used for the isolation and characterization of isolated bioactive molecule named 2, 3-dimethylmaleic anhydride (3, 4-dimethyl-2, 5-furandione). This compound was found to be highly toxic, even at low concentration, against several storage grain pests when used as biofumigant. Experimental studies on the mode of action of 2, 3-dimethylmaleic anhydride revealed that the biofumigant act as inhibitor of acetylcholinesterase enzyme in cockroach and stored grain insects. The knockdown activity of bioactive compound is concurrent with in vivo inhibition of AChE; at KD99 dosage of bioactive molecule showed more than 90% inhibition of AChE activity in test insects. The molecule proved to affect the antioxidant enzyme system; superoxide dismutase (SOD), and catalase (CAT) and also found to decrease reduced glutathione (GSH) level in the treated insects. The above results indicate involvement of inhibition of AChE activity and oxidative imbalance as the potential mode of action of 2, 3-dimethylmaleic anhydride. In addition, the study reveals computational docking programs elaborate the possible interaction of 2, 3-dimethylmaleic anhydride with enzyme acetylcholinesterase (AChE) of Periplaneta americana. Finally, the results represent that toxicity of 2, 3-dimethylmaleic anhydride might be associated with inhibition of AChE activity and oxidative imbalance.

Keywords: 2, 3-dimethylmaleic anhydride, Colocasia esculenta var. esculenta (L.) Schott, Biofumigant, acetylcholinesterase, antioxidant enzyme, molecular docking

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515 A Mathematical Model for 3-DOF Rotary Accuracy Measurement Method Based on a Ball Lens

Authors: Hau-Wei Lee, Yu-Chi Liu, Chien-Hung Liu

Abstract:

A mathematical model is presented for a system that measures rotational errors in a shaft using a ball lens. The geometric optical characteristics of the ball lens mounted on the shaft allows the measurement of rotation axis errors in both the radial and axial directions. The equipment used includes two quadrant detectors (QD), two laser diodes and a ball lens that is mounted on the rotating shaft to be evaluated. Rotational errors in the shaft cause changes in the optical geometry of the ball lens. The resulting deflection of the laser beams is detected by the QDs and their output signals are used to determine rotational errors. The radial and the axial rotational errors can be calculated as explained by the mathematical model. Results from system calibration show that the measurement error is within ±1 m and resolution is about 20 nm. Using a direct drive motor (DD motor) as an example, experimental results show a rotational error of less than 20 m. The most important features of this system are that it does not require the use of expensive optical components, it is small, very easy to set up, and measurements are highly accurate.

Keywords: ball lens, quadrant detector, axial error, radial error

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514 Graphene-Based Reconfigurable Lens Antenna for 5G/6G and Satellite Networks

Authors: André Lages, Victor Dmitriev, Juliano Bazzo, Gianni Portela

Abstract:

This work evaluates the feasibility of the graphene application to perform as a wideband reconfigurable material for lens antennas in 5G/6G and satellite applications. Based on transformation optics principles, the electromagnetic waves can be efficiently guided by modifying the effective refractive index. Graphene behavior can range between a lossy dielectric and a good conductor due to the variation of its chemical potential bias, thus arising as a promising solution for electromagnetic devices. The graphene properties and a lens antenna comprising multiples layers and periodic arrangements of graphene patches were analyzed using full-wave simulations. A dipole directivity was improved from 7 to 18.5 dBi at 29 GHz. In addition, the realized gain was enhanced 7 dB across a 14 GHz bandwidth within the Ka/5G band.

Keywords: 5G/6G, graphene, lens, reconfigurable, satellite

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513 Cavitas Sensors into Human Cavities: Soft-Contact Lens and Mouthguard Sensors

Authors: Kohji Mitsubayashi, Takahiro Arakawa, Kohji Mitsubayashi

Abstract:

‘Cavitas sensors’ attached to human body cavities such as a contact lens type and a mouthguard (‘no implantable', ‘no wearable’) attracted attention as self-detachable devices for daily medicine. In this contribution, the soft contact lens glucose sensor for tear sugar monitoring will be introduced. And the mouthguard sensor with dental materials integrated with Bluetooth low energy (BLE) wireless module for real-time monitoring of saliva glucose would also be demonstrated. In the near future, those self-detachable cavitas sensors are expected to improve quality of life in view of the aging of society.

Keywords: cavitas sensor, biosensor, contact lens, mouthguard

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512 Quantitative Phase Imaging System Based on a Three-Lens Common-Path Interferometer

Authors: Alexander Machikhin, Olga Polschikova, Vitold Pozhar, Alina Ramazanova

Abstract:

White-light quantitative phase imaging is an effective technique for achieving sub-nanometer phase sensitivity. Highly stable interferometers based on common-path geometry have been developed in recent years to solve this task. Some of these methods also apply multispectral approach. The purpose of this research is to suggest a simple and effective interferometer for such systems. We developed a three-lens common-path interferometer, which can be used for quantitative phase imaging with or without multispectral modality. The lens system consists of two components, the first one of which is a compound lens, consisting of two lenses. A pinhole is placed between the components. The lens-in-lens approach enables effective light transmission and high stability of the interferometer. The multispectrality is easily implemented by placing a tunable filter in front of the interferometer. In our work, we used an acousto-optical tunable filter. Some design considerations are discussed and multispectral quantitative phase retrieval is demonstrated.

Keywords: acousto-optical tunable filter, common-path interferometry, digital holography, multispectral quantitative phase imaging

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511 Freeform Lens System for Collimation SERS irradiation Radiation Produced by Biolayers which Deposit on High Quality Resonant System

Authors: Iuliia Riabenko, Konstantin Beloshenko, Sergey Shulga, Valeriy Shulga

Abstract:

An optical system has been developed consisting of a TIR lens and an aspherical surface designed to collect Stokes radiation from biomolecules. The freeform material is SYLGARD-184, which provides a low level of noise associated with the luminescence of the substrate. The refractive index of SYLGARD-184 is 1.4028 for a wavelength of 632 nm, the Abbe number is 72, these material parameters make it possible to design the desired shape for the wavelength range of 640-700 nm. The system consists of a TIR lens, inside which is placed a high-quality resonant system consisting of a biomolecule and a metal colloid. This system can be described using the coupled oscillator model. The laser excitation radiation was fed through the base of the TIR lens. The sample was mounted inside the TIR lens at a distance of 8 mm from the base. As a result of Raman scattering of laser radiation, a Stokes bend appeared from the biolayer. The task of this work was that it was necessary to collect this radiation emitted at a 4π steradian angle. For this, an internal aspherical surface was used, which made it possible to defocus the beam emanating from the biolayer and direct its radiation to the borders of the TIR lens at the Brewster angle. The collated beam of Stokes radiation contains 97% of the energy scattered by the biolayer. Thus, a simple scheme was proposed for collecting and collimating the Stokes radiation of biomolecules.

Keywords: TIR lens, freeform material, raman scattering, biolayer, brewster angle

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510 Laser Beam Bending via Lenses

Authors: Remzi Yildirim, Fatih. V. Çelebi, H. Haldun Göktaş, A. Behzat Şahin

Abstract:

This study is about a single component cylindrical structured lens with gradient curve which we used for bending laser beams. It operates under atmospheric conditions and bends the laser beam independent of temperature, pressure, polarity, polarization, magnetic field, electric field, radioactivity, and gravity. A single piece cylindrical lens that can bend laser beams is invented. Lenses are made of transparent, tinted or colored glasses and used for undermining or absorbing the energy of the laser beams.

Keywords: laser, bending, lens, light, nonlinear optics

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509 Laser Light Bending via Lenses

Authors: Remzi Yildirim, Fatih V. Çelebi, H. Haldun Göktaş, A. Behzat Şahin

Abstract:

This study is about a single component cylindrical structured lens with gradient curve which we used for bending laser beams. It operates under atmospheric conditions and bends the laser beam independent of temperature, pressure, polarity, polarization, magnetic field, electric field, radioactivity, and gravity. A single piece cylindrical lens that can bend laser beams is invented. Lenses are made of transparent, tinted or colored glasses and used for undermining or absorbing the energy of the laser beams.

Keywords: laser, bending, lens, light, nonlinear optics

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508 Freshwater Lens Observation: Case Study of Laura Island, Majuro Atoll, Republic of the Marshall Islands

Authors: Kazuhisa Koda, Tsutomu Kobayashi, Rebecca Lorennji, Alington Robert, Halston DeBrum, Julious Lucky, Paul Paul

Abstract:

Atolls are low-lying small islands with highly permeable ground that does not allow rivers and lakes to develop. As the water resources on these atolls basically rely on precipitation, groundwater becomes a very important water resource during droughts. Freshwater lenses develop as groundwater on relatively large atoll islands and play a key role in the stable water supply. Atoll islands in the Pacific Ocean sometimes suffer from drought due to El Nino. The global warming effects are noticeable, particularly on atoll islands. The Republic of the Marshall Islands in Oceania is burdened with the problems common to atoll islands. About half of its population lives in the capital, Majuro, and securing water resources for these people is a crucial issue. There is a freshwater lens on the largest, Laura Island, which serves as a water source for the downtown area. A serious drought that occurred in 1998 resulted in excessive water intake from the freshwater lens on Laura Island causing up-coning. Up-coning mixes saltwater into groundwater pumped from water-intake wells. Because up-coning makes the freshwater lens unusable, there was a need to investigate the freshwater lens on Laura Island. In this study, we observed the electrical conductivities of the groundwater at different depths in existing monitoring wells to determine the total storage volume of the freshwater lens on Laura Island from 2010 to 2013. Our results indicated that most of the groundwater that seeped into the freshwater lens had flowed out into the sea.

Keywords: Atoll islands, drought, El-Nino, freshwater lens, groundwater observation

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507 3D Simulation of the Twin-Aperture IRON Superconducting Quadrupole for Charm-Tau Factory

Authors: K. K. Riabchenko, T. V Rybitskaya, A. A. Starostenko

Abstract:

Sper Charm-Tau Factory is a double ring e+e- collider to be operated in the center-of-mass energy range from 2 to 6 GeV, with a peak luminosity of about 1035 cm-2s-1 (Crab Waist collision) and with longitudinally polarized electrons at the IP (interaction point). One of the important elements of the cτ-factory is the superconducting two-aperture quadrupole of the final focus. It was decided to make a full-scale prototype quadrupole. The main objectives of our study included: 1) 3D modeling of the quadrupole in the Opera program, 2) Optimization of the geometry of the quadrupole lens, 3) Study of the influence of magnetic properties and geometry of a quadrupole on integral harmonics. In addition to this, the ways of producing unwanted harmonics have been studied. In the course of this work, a 3D model of a two-aperture iron superconducting quadrupole lens was created. A three-dimensional simulation of the magnetic field was performed, and the geometrical parameters of the lens were selected. Calculations helped to find sources of possible errors and methods for correcting unwanted harmonics. In addition to this, calculations show that there are no obstacles to the production of a prototype lens.

Keywords: super cτ-factory, final focus, twin aperture quadrupole lens, integral harmonics

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506 Sustainable Use of Laura Lens during Drought

Authors: Kazuhisa Koda, Tsutomu Kobayashi

Abstract:

Laura Island, which is located about 50 km away from downtown, is a source of water supply in Majuro atoll, which is the capital of the Republic of the Marshall Islands. Low and flat Majuro atoll has neither river nor lake. It is very important for Majuro atoll to ensure the conservation of its water resources. However, up-coning, which is the process of partial rising of the freshwater-saltwater boundary near the water-supply well, was caused by the excess pumping from it during the severe drought in 1998. Up-coning will make the water usage of the freshwater lens difficult. Thus, appropriate water usage is required to prevent up-coning in the freshwater lens because there is no other water source during drought. Numerical simulation of water usage applying SEAWAT model was conducted at the central part of Laura Island, including the water-supply well, which was affected by up-coning. The freshwater lens was created as a result of infiltration of consistent average rainfall. The lens shape was almost the same as the one in 1985. 0 of monthly rainfall and variable daily pump discharge were used to calculate the sustainable pump discharge from the water-supply well. Consequently, the total amount of pump discharge was increased as the daily pump discharge was increased, indicating that it needs more time to recover from up-coning. Thus, a pump standard to reduce the pump intensity is being proposed, which is based on numerical simulation concerning the occurrence of the up-coning phenomenon in Laura Island during the drought.

Keywords: freshwater lens, islands, numerical simulation, sustainable water use

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505 Effect of Mannitol on in Vitro Conservation of Local and Exotic Taro-Genotypes (Colocasia Esculenta Var Esculenta)

Authors: Benjamin Bonsu Bruce, Marian Dorcas Quain David Appiah-Kubi, Gertrude Osei-Diko, Harrison Kwame Dapaah

Abstract:

Taro [Colocasia esculenta (L.) Schott] is a major staple food and remains a significant crop to many cultural and agricultural customs worldwide. In Ghana, taro is mostly propagated using vegetative material, which is conserved in field collection and recycled from their farms to establish new fields. However, this practice promotes the accumulation of systemic pathogens. Prior exposure to pests and subsequent expression of disease symptoms can also be a huge constraint to sustainable conservation and utilization of taro genetic resources. In vitro, slow growth is one of the most promising techniques to be utilized for conservation. The objective of this study was to find a medium-term in vitro conservation protocol for local and exotic taro genotypes. The medium-term conservation study was conducted using actively growing shoots obtained from in vitro cultures. Explants were cultured to full strength in complete Murashige and Skoog medium supplemented with Mannitol at different concentrations (0g/l, 20g/l, 25g/l, and 30g/l). Another medium that was tested as an additional treatment is the White’s medium. The highest number of shoots (6.33) and leaves (22.67) occurred on medium containing 20 and 25g/l mannitol in genotype SAO 006 as compared to other genotypes, whereas 30g/l mannitol was the best to restrict growth for the entire 6 months period in terms of shoot height (22.50cm). The study reveals that mannitol supplemented culture media could reduce the growth of Colocasia plantlets, especially in stem height. Culture growth following 6 months of conservation, showed that healthy shoot cultures of Taro were obtained after 6 months of storage in a medium containing 20gl⁻¹ and 25gl⁻¹ mannitol.

Keywords: complete murashige, skoog medium, culture conditions, mannitol, slow growth conservation

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504 Simulation and Fabrication of Plasmonic Lens for Bacteria Detection

Authors: Sangwoo Oh, Jaewoo Kim, Dongmin Seo, Jaewon Park, Yongha Hwang, Sungkyu Seo

Abstract:

Plasmonics has been regarded one of the most powerful bio-sensing modalities to evaluate bio-molecular interactions in real-time. However, most of the plasmonic sensing methods are based on labeling metallic nanoparticles, e.g. gold or silver, as optical modulation markers, which are non-recyclable and expensive. This plasmonic modulation can be usually achieved through various nano structures, e.g., nano-hole arrays. Among those structures, plasmonic lens has been regarded as a unique plasmonic structure due to its light focusing characteristics. In this study, we introduce a custom designed plasmonic lens array for bio-sensing, which was simulated by finite-difference-time-domain (FDTD) approach and fabricated by top-down approach. In our work, we performed the FDTD simulations of various plasmonic lens designs for bacteria sensor, i.e., Samonella and Hominis. We optimized the design parameters, i.e., radius, shape, and material, of the plasmonic lens. The simulation results showed the change in the peak intensity value with the introduction of each bacteria and antigen i.e., peak intensity 1.8711 a.u. with the introduction of antibody layer of thickness of 15nm. For Salmonella, the peak intensity changed from 1.8711 a.u. to 2.3654 a.u. and for Hominis, the peak intensity changed from 1.8711 a.u. to 3.2355 a.u. This significant shift in the intensity due to the interaction between bacteria and antigen showed a promising sensing capability of the plasmonic lens. With the batch processing and bulk production of this nano scale design, the cost of biological sensing can be significantly reduced, holding great promise in the fields of clinical diagnostics and bio-defense.

Keywords: plasmonic lens, FDTD, fabrication, bacteria sensor, salmonella, hominis

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503 Fracture Control of the Soda-Lime Glass in Laser Thermal Cleavage

Authors: Jehnming Lin

Abstract:

The effects of the contact ball-lens on the soda lime glass in laser thermal cleavage with a cw Nd-YAG laser were investigated in this study. A contact ball-lens was adopted to generate a bending force on the crack formation of the soda-lime glass in the laser cutting process. The Nd-YAG laser beam (wavelength of 1064 nm) was focused through the ball-lens and transmitted to the soda-lime glass, which was coated with a carbon film on the surface with a bending force from a ball-lens to generate a tensile stress state on the surface cracking. The fracture was controlled by the contact ball-lens and a straight cutting was tested to demonstrate the feasibility. Experimental observations on the crack propagation from the leading edge, main section and trailing edge of the glass sheet were compared with various mechanical and thermal loadings. Further analyses on the stress under various laser powers and contact ball loadings were made to characterize the innovative technology. The results show that the distributions of the side crack at the leading and trailing edges are mainly dependent on the boundary condition, contact force, cutting speed and laser power. With the increase of the mechanical and thermal loadings, the region of the side cracks might be dramatically reduced with proper selection of the geometrical constraints. Therefore, the application of the contact ball-lens is a possible way to control the fracture in laser cleavage with improved cutting qualities.

Keywords: laser cleavage, stress analysis, crack visualization, laser

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502 Experimental Study of Tunable Layout Printed Fresnel Lens Structure Based on Dye Doped Liquid Crystal

Authors: M. Javadzadeh, H. Khoshsima

Abstract:

In this article, we present a layout printing way for producing Fresnel zone on 1294-1b doped liquid crystal with Methyl-Red azo dye. We made a Fresnel zone mask with 25 zones and radius of 5 mm using lithography technique. With layout printing way, we recorded mask’s pattern on cell with λ=532 nm solid-state diode pump laser. By recording Fresnel zone pattern on cell and making Fresnel pattern on the surface of cell, odd and even zones, will form. The printed pattern, because of Azo dye’s photoisomerization, was permanent. Experimentally, we saw focal length tunability from 32 cm to 43 cm.

Keywords: liquid crystal, lens, Fresnel zone, diffraction, Fresnel lens

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501 Effects of Deficit Watering and Potassium Fertigation on Growth and Yield Response of Cassava

Authors: Daniel O. Wasonga, Jouko Kleemola, Laura Alakukku, Pirjo Makela

Abstract:

Cassava (Manihot esculenta Crantz) is a major food crop for millions of people in the tropics. Growth and yield of cassava in the arid-tropics are seriously constrained by intermittent water deficit and low soil K content. Therefore, experiments were conducted to investigate the effects of interaction between water deficit and K fertigation on growth and yield response of biofortified cassava at early growth phase. Yellow cassava cultivar was grown under controlled glasshouse conditions in 5-L pots containing 1.7 kg of pre-fertilized potting mix. Plants were watered daily for 30 days after planting. Treatments were three watering levels (30%, severe water deficit; 60%, mild water deficit; 100%, well-watered), on which K (0.01, 1, 4, 16 and 32 mM) was split. Plants were harvested at 90 days after planting. Leaf area was smallest in plants grown with 30% watering and 0.01 mM K, and largest in plants grown with 100% watering and 32 mM K. Leaf, root, and total dry mass decreased in water-stressed plants. However, dry mass was markedly higher when plants were grown with 16 mM K under all watering levels in comparison to other K concentrations. The highest leaf, root and total dry mass were in plants with 100% watering and 16 mM K. In conclusion, K improved the growth of plants under water deficit and thus, K application on soils with low moisture and low K may improve the productivity of cassava.

Keywords: dry mass, interaction, leaf area, Manihot esculenta

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500 Systemic Factors, Intraocular Lens, and Ocular Abnormalities in Patients with Intraocular Lens Glistening at a Tertiary Hospital in Semarang

Authors: Azmi Ilmi Aziz, Wisnu Sadasih, Rizal Fanany

Abstract:

Purpose: This study describes systemic factors, intraocular lens (IOL), and ocular abnormalities in patients with IOL glistening at a tertiary hospital in Semarang. Methods: A retrospective, with a descriptive approach on patients with IOL glistening who visited the eye clinic between August 2019 to June 2023. Results: Twenty-five patients were examined; 11 patients (44%) had IOL glistening in their right eye, 4 patients (16%) in their left eye, and 10 patients (40%) in both eyes. The gender of patients consisted of 12 male patients (48%) and 13 female patients (52%). The median age of the patients was 68 years. The mean onset was 4.44 years after the first cataract surgery. Hypertension was found in 13 patients (52%), and diabetes was found in 9 patients (36%). Nine patients (36%) were identified with a foldable IOL with a closed loop design, and 1 patient (4%) with a PMMA IOL with an iris-fixated IOL design, while 15 other patients’ IOL were unrecorded. Glaucoma was found in 3 patients (12%). Conclusions: The result of this study showed that more than half of the patients were hypertensive, and some were glaucomatous, which had been discussed relevant in previous studies. Most IOL that could be identified was foldable IOL with a closed loop design. To our knowledge, the design of an IOL to glistening had never been explored. A longer study involving larger subjects is needed to better describe the systemic factors, IOL, and ocular abnormalities in patients with IOL glistening.

Keywords: glistening, intraocular lens, foldable IOL, PMMA IOL

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499 Development and Characterization of Biscuits Incorporated with Jackfruit (Artocarpus heterophyllus) Seeds and Cassava (Manihot esculenta)

Authors: Elina Brahma Hazarika, Jeuti Basumatary, Deepanka Saikia, Jaydeep Das, Micky Moni D'mary, Fungkha Basumatary

Abstract:

This study includes development of two varieties of biscuits incorporated with: the seeds of Jack fruit (Artocarpus heterophyllus), which post-consumption of it’s pulp, is discarded as a waste, and Cassava (Manihot esculenta) tubers.The jack fruit seeds and cassava were first ground into flour and its proximate and physiochemical properties were studied. The biscuits that were developed incorporating them had 50% wheat flour and 50% jackfruit seed flour and 50% cassava flours as the major composition, apart from the other general ingredients use in making biscuits. Various trials of compositions were made for baking to get the overall desirable acceptability in biscuits through sensory evaluation. Finally, the best composition of ingredients was selected to make the biscuits, and hence studies were done accordingly to compare it with the properties of their respective raw flours. The results showed that the proximate composition of the biscuits fared better than that of their respective flours: There was a decrease in the Moisture content of both Jackfruit Seed Biscuits and Cassava Biscuits to 4.5% and 6.7% than that of their respective raw flours (8 and 12%). Post-baking, there is increase in the percentages of ash, protein, and fibre contents in both Jackfruit Seed Biscuits and Cassava Biscuits; the values being 3% and 3.8%, 13.2% and 3.3%, and 3.2 and 4.1% respectively. Also the total carbohydrate content in Jackfruit Seed Biscuits and Cassava Biscuits were 66.7% and 71.7% respectively. Their sensory evaluation and texture study also yielded a clear review that they have an overall good acceptability.

Keywords: baking, proximate, sensory, texture

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498 Sustainable Use of Fresh Groundwater Lens of Pleistocene Aquifer in Nam Dinh, Vietnam

Authors: Tran Thanh Le, Pham Trong Duc

Abstract:

The fresh groundwater lens of the Pleistocene aquifer in Nam Dinh was formed since 12,900 years ago. Currently, the Pleistocene aquifer has been continuously exploited on average of 154,163m3/day, distributed mainly in the districts of Nghia Hung, Hai Hau, a part of Truc Ninh, Y Yen, Nam Truc and Giao Thuy. The groundwater level is still on a declining trend, saltwater intrusion in this freshwater lens can occur if the growth rate in exploitation is maintained. This study focused on groundwater sustainable use by means of 4 groups of criteria including: Groundwater quality and pollution; Aquifers’ productivity and capacity; Environment impacts due to exploitation (groundwater level decline, land subsidence due to water exploitation); Social and economic impacts. Using a combination of methods including field surveys, geophysics, hydrogeochemistry, isotope and numerical models to determine safe groundwater exploitation thresholds for the whole study area has been determined to be 544,314m3/day and the actual exploitation amount is currently about 30% compared to the safe exploitation threshold. However, it should also be noted that the current groundwater exploitation threshold and level of its exploitation compared to the safe exploitation threshold of each locality are not the same. From this result, the groundwater exploitation threshold map of the study area was established to serve the management, licensing and orientation of groundwater exploitation.

Keywords: criteria, groundwater, fresh groundwater lens, pleistocene, Nam Dinh

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497 Noncritical Phase-Matched Fourth Harmonic Generation of Converging Beam by Deuterated Potassium Dihydrogen Phosphate Crystal

Authors: Xiangxu Chai, Bin Feng, Ping Li, Deyan Zhu, Liquan Wang, Guanzhong Wang, Yukun Jing

Abstract:

In high power large-aperture laser systems, such as the inertial confinement fusion project, the Nd: glass laser (1053nm) is usually needed to be converted to ultraviolet (UV) light and the fourth harmonic generation (FHG) is one of the most favorite candidates to achieve UV light. Deuterated potassium dihydrogen phosphate (DKDP) crystal is an optimal choice for converting the Nd: glass radiation to the fourth harmonic laser by noncritical phase matching (NCPM). To reduce the damage probability of focusing lens, the DKDP crystal is suggested to be set before the focusing lens. And a converging beam enters the FHG crystal consequently. In this paper, we simulate the process of FHG in the scheme and the dependence of FHG efficiency on the lens’ F is derived. Besides, DKDP crystal with gradient deuterium is proposed to realize the NCPM FHG of the converging beam. At every position, the phase matching is achieved by adjusting the deuterium level, and the FHG efficiency increases as a result. The relation of the lens’ F with the deuterium gradient is investigated as well.

Keywords: fourth harmonic generation, laser induced damage, converging beam, DKDP crystal

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496 Case Report: Ocular Helminth – In Unusual Site (Lens)

Authors: Chandra Shekhar Majumder, Shamsul Haque, Khondaker Anower Hossain, Rafiqul Islam

Abstract:

Introduction: Ocular helminths are parasites that infect the eye or its adnexa. They can be either motile worms or sessile worms that form cysts. These parasites require two hosts for their life cycle, a definite host (usually a human) and an intermediate host (usually an insect). While there have been reports of ocular helminths infecting various structures of the eye, including the anterior chamber and subconjunctival space, there is no previous record of such a case involving the lens. Research Aim: The aim of this case report is to present a rare case of ocular helminth infection in the lens and to contribute to the understanding of this unusual site of infection. Methodology: This study is a case report, presenting the details and findings of an 80-year-old retired policeman who presented with severe pain, redness, and vision loss in the left eye. The examination revealed the presence of a thread-like helminth in the lens. The data for this case report were collected through clinical examination and medical records of the patient. The findings were described and presented in a descriptive manner. No statistical analysis was conducted. Case report: An 80-year-old retired policeman attended the OPD, Faridpur Medical College Hospital with the complaints of severe pain, redness and gross dimness of vision of the left eye for 5 days. He had a history of diabetes mellitus and hypertension for 3 years. On examination, L/E visual acuity was PL only, moderate ciliary congestion, KP 2+, cells 2+ and posterior synechia from 5 to 7 O’clock position was found. Lens was opaque. A thread like helminth was found under the anterior of the lens. The worm was moving and changing its position during examination. On examination of R/E, visual acuity was 6/36 unaided, 6/18 with pinhole. There was lental opacity. Slit-lamp and fundus examination were within normal limit. Patient was admitted in Faridpur Medical College Hospital. Diabetes mellitus was controlled with insulin. ICCE with PI was done on the same day of admission under depomedrol coverage. The helminth was recovered from the lens. It was thread like, about 5 to 6 mm in length, 1 mm in width and pinkish in colour. The patient followed up after 7 days, VA was HM, mild ciliary congestion, few KPs and cells were present. Media was hazy due to vitreous opacity. The worm was sent to the department of Parasitology, NIPSOM, Dhaka for identification. Theoretical Importance: This case report contributes to the existing literature on ocular helminth infections by reporting a unique case involving the lens. It highlights the need for further research to understand the mechanism of entry of helminths in the lens. Conclusion: To the best of our knowledge, this is the first reported case of ocular helminth infection in the lens. The presence of the helminth in the lens raises interesting questions regarding its pathogenesis and entry mechanism. Further study and research are needed to explore these aspects. Ophthalmologists and parasitologists should be aware of the possibility of ocular helminth infections in unusual sites like the lens.

Keywords: helminth, lens, ocular, unusual

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495 Intensity-Enhanced Super-Resolution Amplitude Apodization Effect on the Non-Spherical Near-Field Particle-Lenses

Authors: Liyang Yue, Bing Yan, James N. Monks, Rakesh Dhama, Zengbo Wang, Oleg V. Minin, Igor V. Minin

Abstract:

A particle can function as a refractive lens to focus a plane wave, generating a narrow, high intensive, weak-diverging beam within a sub-wavelength volume, known as the ‘photonic jet’. Refractive index contrast (particle to background media) and scaling effect of the dielectric particle (relative-to-wavelength size) play key roles in photonic jet formation, rather than the shape of particle-lens. Waist (full width of half maximum, FWHM) of a photonic jet could be beyond the diffraction limit and smaller than the Airy disk, which defines the minimum distance between two objects to be imaged as two instead of one. Many important applications for imaging and sensing have been afforded based upon the super-resolution characteristic of the photonic jet. It is known that apodization method, in the form of an amplitude pupil-mask centrally situated on a particle-lens, can further reduce the waist of a photonic nanojet, however, usually lower its intensity at the focus due to blocking of the incident light. In this paper, the anomalously intensity-enhanced apodization effect was discovered in the near-field via numerical simulation. It was also experimentally verified by a scale model using a copper-masked Teflon cuboid solid immersion lens (SIL) with 22 mm side length under radiation of a plane wave with 8 mm wavelength. Peak intensity enhancement and the lateral resolution of the produced photonic jet increased by about 36.0 % and 36.4 % in this approach, respectively. This phenomenon may possess the scale effect and would be valid in multiple frequency bands.

Keywords: apodization, particle-lens, scattering, near-field optics

Procedia PDF Downloads 163