Search results for: cancer stem cell (CSC)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5493

Search results for: cancer stem cell (CSC)

2283 Studies on Radio Frequency Sputtered Copper Zinc Tin Sulphide Absorber Layers for Thin Film Solar Cells

Authors: G. Balaji, R. Balasundaraprabhu, S. Prasanna, M. D. Kannan, K. Sivakumaran, David Mcilroy

Abstract:

Copper Zin tin sulphide (Cu2ZnSnS4 or CZTS) is found to be better alternative to Copper Indium gallium diselenide as absorber layers in thin film based solar cells due to the utilisation of earth-abundant materials in the midst of lower toxicity. In the present study, Cu2ZnSnS4 thin films were prepared on soda lime glass using (CuS, ZnS, SnS) targets and were deposited by three different stacking orders, using RF Magnetron sputtering. The substrate temperature was fixed at 300 °C during the depositions. CZTS thin films were characterized using X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy and UV-Vis-NIR spectroscopy. All the samples exhibited X-ray peaks pertaining to (112) kesterite phase of CZTS, along with the presence of a predominant wurtzite CZTS phase. X-ray photoelectron spectroscopy revealed the presence of all the elements in all the samples. The change in stacking order clearly shows that it affects the structural and phase properties of the films. Relative atomic concentrations of Zn, Cu, Sn and S, which are determined by high-resolution XPS core level spectra integrated peak areas revealed that the CZTS films exhibit inhomogeneity in both stoichiometry and elemental composition. Raman spectroscopy studies on the film showed the presence of CZTS phase. The energy band gap of the CZTS thin films was found to be in the range of 1.5 eV to 1.6 eV. The films were then annealed at 450 °C for 5 hrs and it was found that the predominant nature of the X-ray peaks has transformed from Wurtzite to Kesterite phase which is highly desirable for absorber layers in thin film solar cells. The optimized CZTS layer was used as an absorber layer in thin film solar cells. ZnS and CdS were used as buffer layers which in turn prepared by Hot wall epitaxy technique. Gallium doped Zinc oxide was used as a transparent conducting oxide. The solar cell structure Glass/Mo/CZTS/CdS or ZnS/GZO has been fabricated, and solar cell parameters were measured.

Keywords: earth-abundant, Kesterite, RF sputtering, thin film solar cells

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2282 A Distributed Smart Battery Management System – sBMS, for Stationary Energy Storage Applications

Authors: António J. Gano, Carmen Rangel

Abstract:

Currently, electric energy storage systems for stationary applications have known an increasing interest, namely with the integration of local renewable energy power sources into energy communities. Li-ion batteries are considered the leading electric storage devices to achieve this integration, and Battery Management Systems (BMS) are decisive for their control and optimum performance. In this work, the advancement of a smart BMS (sBMS) prototype with a modular distributed topology is described. The system, still under development, has a distributed architecture with modular characteristics to operate with different battery pack topologies and charge capacities, integrating adaptive algorithms for functional state real-time monitoring and management of multicellular Li-ion batteries, and is intended for application in the context of a local energy community fed by renewable energy sources. This sBMS system includes different developed hardware units: (1) Cell monitoring units (CMUs) for interfacing with each individual cell or module monitoring within the battery pack; (2) Battery monitoring and switching unit (BMU) for global battery pack monitoring, thermal control and functional operating state switching; (3) Main management and local control unit (MCU) for local sBMS’s management and control, also serving as a communications gateway to external systems and devices. This architecture is fully expandable to battery packs with a large number of cells, or modules, interconnected in series, as the several units have local data acquisition and processing capabilities, communicating over a standard CAN bus and will be able to operate almost autonomously. The CMU units are intended to be used with Li-ion cells but can be used with other cell chemistries, with output voltages within the 2.5 to 5 V range. The different unit’s characteristics and specifications are described, including the different implemented hardware solutions. The developed hardware supports both passive and active methods for charge equalization, considered fundamental functionalities for optimizing the performance and the useful lifetime of a Li-ion battery package. The functional characteristics of the different units of this sBMS system, including different process variables data acquisition using a flexible set of sensors, can support the development of custom algorithms for estimating the parameters defining the functional states of the battery pack (State-of-Charge, State-of-Health, etc.) as well as different charge equalizing strategies and algorithms. This sBMS system is intended to interface with other systems and devices using standard communication protocols, like those used by the Internet of Things. In the future, this sBMS architecture can evolve to a fully decentralized topology, with all the units using Wi-Fi protocols and integrating a mesh network, making unnecessary the MCU unit. The status of the work in progress is reported, leading to conclusions on the system already executed, considering the implemented hardware solution, not only as fully functional advanced and configurable battery management system but also as a platform for developing custom algorithms and optimizing strategies to achieve better performance of electric energy stationary storage devices.

Keywords: Li-ion battery, smart BMS, stationary electric storage, distributed BMS

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2281 Q Eqchi Mayan Piper and Cissampelos Species Alter Reporter Genes and Endogenous Genes Expression in Mc-7 Cells

Authors: Sheila M. Wicks, Gail Mahady, Udesh Patel, Joanna Michel, Armando Caceres

Abstract:

Introduction: The genus piperaceae contains approximately 1000 species of herbs scrubs small trees and hanging vines distributed in both hemispheres. During our ethno medical work in Guatemala of the 27 plant families documented for us e by the Qeqchi Maya for reproductive disorders the most prominent were the Piperaceae (15%) and Menispermiaceae. Our Previous work showed that extracts from form Piper and Cissampelos species bound to both and progesterone and the estrogen receptors. In this work active extracts from Piper aeruginosibaccum Trelease, P auritum, P tuerckheimii and Cissampels tropaeolifolia were tested in functionalized cell based assays including a SEAP reporter gene and by qPCR of ER-responsive gene expression in MCF-7cells. In the reporter gene assay P aeruginosibaccum was estrogenic and enhanced E2 EFFECTS IN MCF-7 CELLS. P. tuerckheimi was not estrogenic alone but significantly enhanced the effects of E2 on SEAP reporter gene expression. Both altered mRNA expression of E2 responsive genes in MCF-7. Methods: this is collaborative project between University of Illinois at Chicago and University of San Carlos Guatemala City. 144 spices of plants were collected in Guatemala of which 57 used to treat a variety of women's reproductive health. The Genus Piperaraceae contains approximately 1000 species of herbs scrubs and small trees. Active extracts of the plants were tested in functionalized in cell-based bioassays including SEAP reporter genes. Results demonstrated altered mRNA expression of E2 responsive genes in MC-7 cells plants were collected in Guatemala of which 57 used. Conclusion of the 5 plants tested all were shown to contain components of binding to estrogenic receptor to a greater or lesser degree. These effects support the use of QEqchi Maya women in Guatemala for reproductive.

Keywords: reporter genes, MC7, guatemala piperaceae, reproductive health

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2280 The Experiences of Rural Family Caregivers of Cancer Patients in Newfoundland and Labrador and Their Challenges and Needs in Relocating to Urban Settings for Treatment

Authors: Mei Li, Victor Meddalena

Abstract:

Background: Newfoundland and Labrador (NL) has rapidly aging population and is characterized by its vast geography with high proportion of dispersed rural communities when compared to other provinces in Canada. Structural, demographic and geographic factors have created big gaps for rural residents across NL with respect to accessing various health and social services. While the barriers are well documented for patients’ access to cancer care in rural and remote areas, challenges faced by family caregivers are not fully recognized. Caregiving burden coupled with challenges associated with relocation and frequent travels create situations where caregivers are vulnerable physically, emotionally, financially and socially. This study examines the experiences of family caregivers living in rural NL through a social justice lens. It is expected to identify the gaps existing in social policy and support for rural family caregivers. It will make a novel contribution to the literature in this regard. Methods: Design: This qualitative study adopted the hermeneutic phenomenology to best describe and interpret rural-based family caregivers’ living experiences and explore the meaning, impact, and the influence of both individual experience and contextual factors shaping these experiences. Data Collection: In-depth interviews with key informants were conducted with 12 participants from various rural communities in NL. A case study was also used to explore an individual’s experience in complex social units consisting of multiple variables of in-depth understanding of the reality. Data Analysis: Thematic analysis guided by the Voice-Centred Relational (VCR) method was employed to explore the relationships and contexts of participants. Emerging Themes: Six major emerging themes were identified, namely, overwhelming caregiving burden on rural family caregivers, long existing financial hardship, separation from family and community, low level of social support and self-reliance coping strategies, and social vulnerability and isolation. Conclusion: Understanding the lived experiences of rural-based family caregivers is critical to inform the policy makers the gap of health and social service in NL. The findings of this study also have implications for family caregivers who are vulnerable in other similar contexts. This study adds innovative insights for policy making and service provision in this regard.

Keywords: family caregivers, policy, relocation, rural

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2279 Automatic Segmentation of Lung Pleura Based On Curvature Analysis

Authors: Sasidhar B., Bhaskar Rao N., Ramesh Babu D. R., Ravi Shankar M.

Abstract:

Segmentation of lung pleura is a preprocessing step in Computer-Aided Diagnosis (CAD) which helps in reducing false positives in detection of lung cancer. The existing methods fail in extraction of lung regions with the nodules at the pleura of the lungs. In this paper, a new method is proposed which segments lung regions with nodules at the pleura of the lungs based on curvature analysis and morphological operators. The proposed algorithm is tested on 06 patient’s dataset which consists of 60 images of Lung Image Database Consortium (LIDC) and the results are found to be satisfactory with 98.3% average overlap measure (AΩ).

Keywords: curvature analysis, image segmentation, morphological operators, thresholding

Procedia PDF Downloads 584
2278 Neuroprotective Effect of Vildagliptin against Cerebral Ischemia in Rats

Authors: Salma A. El-Marasy, Rehab F. Abdel-Rahman, Reham M. Abd-Elsalam

Abstract:

The burden of stroke is intensely increasing worldwide. Brain injury following transient or permanent focal cerebral ischemia develops ischemic stroke as a consequence of a complex series of pathophysiological events. The aim of this study is to evaluate the possible neuroprotective effect of a dipeptidyl peptidase-4 inhibitor, vildagliptin, independent on its insulinotropic properties in non-diabetic rats subjected to cerebral ischemia. Anaesthetized Wistar rats were subjected to either left middle cerebral artery occlusion (MCAO) or sham operation followed by reperfusion after 30 min of MCAO. The other three groups were orally administered vildagliptin at 3 dose levels (2.5, 5, 10 mg/kg) for 3 successive weeks before subjected to left focal cerebral ischemia/reperfusion and till the end of the study. Neurological deficit scores and motor activity were assessed 24h following reperfusion. 48h following reperfusion, rats were euthanized and their left brain hemispheres were harvested and used in the biochemical, histopathological, and immunohistochemical investigations. Vildagliptin pretreatment improved neurological score deficit, locomotor activity and motor coordination in MCAO rats. Moreover, vildagliptin reduced malondialdehyde (MDA), elevated reduced glutathione (GSH), phosphotylinosital 3 kinase (PI3K), phosphorylated of protein kinase B (p-AKT), and mechanistic target of rapamycin (mTOR) brain contents in addition to reducing protein expression of caspase-3. Also, vildagliptin showed a dose-dependent attenuation in neuronal cell loss and histopathological alterations in MCAO rats. This study proves that vildagliptin exerted the neuroprotective effect in a dose-dependent manner as shown in amelioration of neuronal cell loss and histopathological damage in MCAO rats, which may be mediated by attenuating neuronal and motor deficits, it’s anti-oxidant property, activation of PI3K/AKT/mTOR pathway and its anti-apoptotic effect.

Keywords: caspase-3, cerebral ischemia, dipeptidyl peptidase-4 inhibitor, oxidative stress, PI3K/AKT/mTOR pathway, rats, vildagliptin

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2277 Response of Chickpea (Cicer arietinum L.) Genotypes to Drought Stress at Different Growth Stages

Authors: Ali. Marjani, M. Farsi, M. Rahimizadeh

Abstract:

Chickpea (Cicer arietinum L.) is one of the important grain legume crops in the world. However, drought stress is a serious threat to chickpea production, and development of drought-resistant varieties is a necessity. Field experiments were conducted to evaluate the response of 8 chickpea genotypes (MCC* 696, 537, 80, 283, 392, 361, 252, 397) and drought stress (S1: non-stress, S2: stress at vegetative growth stage, S3: stress at early bloom, S4: stress at early pod visible) at different growth stages. Experiment was arranged in split plot design with four replications. Difference among the drought stress time was found to be significant for investigated traits except biological yield. Differences were observed for genotypes in flowering time, pod information time, physiological maturation time and yield. Plant height reduced due to drought stress in vegetative growth stage. Stem dry weight reduced due to drought stress in pod visibly. Flowering time, maturation time, pod number, number of seed per plant and yield cause of drought stress in flowering was also reduced. The correlation between yield and number of seed per plant and biological yield was positive. The MCC283 and MCC696 were the high-tolerance genotypes. These results demonstrated that drought stress delayed phonological growth in chickpea and that flowering stage is sensitive.

Keywords: chickpea, drought stress, growth stage, tolerance

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2276 Sports: A Vital Tool for Promotion of Good Health and Prevention of Diseases

Authors: Agburuga Obi, Madumere Akuego Jane

Abstract:

This paper explores the important role sports can play in the promotion of good health and prevention of diseases. Technological advancements in today’s world has come along with some difficulties to man. This is because work formally done by man has been taken over by machines, thus, man has become sedentary. This has created a lot of health problems to man such as cardiovascular diseases, diabetes, cancer, obesity, and osteoporosis. To nip this ugly situation in the bud, the following recommendations are made: specific measures should be taken to raise the awareness within the government, key sectors and the population of the diverse benefits or physical activity and sports and the risk and costs of inactivity, provision of equipment, facilities for sports and recreational activities in every community, participation in physical activities in sports if not on daily basis at least thrice a week.

Keywords: physical activities, sport, good health, prevention, diseases

Procedia PDF Downloads 755
2275 In Vitro Studies on Antimicrobial Activities of Lactic Acid Bacteria Isolated from Fresh Fruits for Biocontrol of Pathogens

Authors: Okolie Pius Ifeanyi, Emerenini Emilymary Chima

Abstract:

Aims: The study investigated the diversity and identities of Lactic Acid Bacteria (LAB) isolated from different fresh fruits using Molecular Nested PCR analysis and the efficacy of cell free supernatants from Lactic Acid Bacteria (LAB) isolated from fresh fruits for in vitro control of some tomato pathogens. Study Design: Nested PCR approach was used in this study employing universal 16S rRNA gene primers in the first round PCR and LAB specific Primers in the second round PCR with the view of generating specific Nested PCR products for the LAB diversity present in the samples. The inhibitory potentials of supernatant obtained from LAB isolates of fruits origin that were molecularly characterized were investigated against some tomato phytopathogens using agar-well method with the view to develop biological agents for some tomato disease causing organisms. Methodology: Gram positive, catalase negative strains of LAB were isolated from fresh fruits on Man Rogosa and Sharpe agar (Lab M) using streaking method. Isolates obtained were molecularly characterized by means of genomic DNA extraction kit (Norgen Biotek, Canada) method. Standard methods were used for Nested Polymerase Chain Reaction (PCR) amplification targeting the 16S rRNA gene using universal 16S rRNA gene and LAB specific primers, agarose gel electrophoresis, purification and sequencing of generated Nested PCR products (Macrogen Inc., USA). The partial sequences obtained were identified by blasting in the non-redundant nucleotide database of National Center for Biotechnology Information (NCBI). The antimicrobial activities of characterized LAB against some tomato phytopathogenic bacteria which include (Xanthomonas campestries, Erwinia caratovora, and Pseudomonas syringae) were obtained by using the agar well diffusion method. Results: The partial sequences obtained were deposited in the database of National Centre for Biotechnology Information (NCBI). Isolates were identified based upon the sequences as Weissella cibaria (4, 18.18%), Weissella confusa (3, 13.64%), Leuconostoc paramensenteroides (1, 4.55%), Lactobacillus plantarum (8, 36.36%), Lactobacillus paraplantarum (1, 4.55%) and Lactobacillus pentosus (1, 4.55%). The cell free supernatants of LAB from fresh fruits origin (Weissella cibaria, Weissella confusa, Leuconostoc paramensenteroides, Lactobacillus plantarum, Lactobacillus paraplantarum and Lactobacillus pentosus) can inhibits these bacteria by creating clear zones of inhibition around the wells containing cell free supernatants of the above mentioned strains of lactic acid bacteria. Conclusion: This study shows that potentially LAB can be quickly characterized by molecular methods to specie level by nested PCR analysis of the bacteria isolate genomic DNA using universal 16S rRNA primers and LAB specific primer. Tomato disease causing organisms can be most likely biologically controlled by using extracts from LAB. This finding will reduce the potential hazard from the use of chemical herbicides on plant.

Keywords: nested pcr, molecular characterization, 16s rRNA gene, lactic acid bacteria

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2274 Immune Modulation and Cytomegalovirus Reactivation in Sepsis-Induced Immunosuppression

Authors: G. Lambe, D. Mansukhani, A. Shetty, S. Khodaiji, C. Rodrigues, F. Kapadia

Abstract:

Introduction: Sepsis is known to cause impairment of both innate and adaptive immunity and involves an early uncontrolled inflammatory response, followed by a protracting immunosuppression phase, which includes decreased expression of cell receptors, T cell anergy and exhaustion, impaired cytokine production, which may cause high risk for secondary infections due to reduced response to antigens. Although human cytomegalovirus (CMV) is widely recognized as a serious viral pathogen in sepsis and immunocompromised patients, the incidence of CMV reactivation in patients with sepsis lacking strong evidence of immunosuppression is not well defined. Therefore, it is important to determine an association between CMV reactivation and sepsis-induced immunosuppression. Aim: To determine the association between incidence of CMV reactivation and immune modulation in sepsis-induced immunosuppression with time. Material and Methods: Ten CMV-seropositive adult patients with severe sepsis were included in this study. Blood samples were collected on Day 0, and further weekly up to 21 days. CMV load was quantified by real-time PCR using plasma. The expression of immunosuppression markers, namely, HLA-DR, PD-1, and regulatory T cells, were determined by flow cytometry using whole blood. Results: At Day 0, no CMV reactivation was observed in 6/10 patients. In these patients, the median length for reactivation was 14 days (range, 7-14 days). The remaining four patients, at Day 0, had a mean viral load of 1802+2599 copies/ml, which increased with time. At Day 21, the mean viral load for all 10 patients was 60949+179700 copies/ml, indicating that viremia increased with the length of stay in the hospital. HLA-DR expression on monocytes significantly increased from Day 0 to Day 7 (p = 0.001), following which no significant change was observed until Day 21, for all patients except 3. In these three patients, HLA-DR expression on monocytes showed a decrease at elevated viral load (>5000 copies/ml), indicating immune suppression. However, the other markers, PD-1 and regulatory T cells, did not show any significant changes. Conclusion: These preliminary findings suggest that CMV reactivation can occur in patients with severe sepsis. In fact, the viral load continued to increase with the length of stay in the hospital. Immune suppression, indicated by decreased expression of HLA-DR alone, was observed in three patients with elevated viral load.

Keywords: CMV reactivation, immune suppression, sepsis immune modulation, CMV viral load

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2273 Regulation of Differentiating Intramuscular Stromal Vascular Cells Isolated from Hanwoo Beef Cattle by Retinoic Acid and Calcium

Authors: Seong Gu Hwang, Young Kyoon Oh, Joseph F. dela Cruz

Abstract:

Marbling, or intramuscular fat, has been consistently identified as one of the top beef quality problems. Intramuscular adipocytes distribute throughout the perimysial connective tissue of skeletal muscle and are the major site for the deposition of intramuscular fat, which is essential for the eating quality of meat. The stromal vascular fraction of the skeletal muscle contains progenitor cells that can be enhanced to differentiate to adipocytes and increase intramuscular fat. Primary cultures of bovine intramuscular stromal vascular cells were used in this study to elucidate the effects of extracellular calcium and retinoic acid concentration on adipocyte differentiation. Cell viability assay revealed that even at different concentrations of calcium and retinoic acid, there was no significant difference on cell viability. Monitoring of the adipocyte differentiation showed that bovine intramuscular stromal vascular cells cultured in a low concentration of extracellular calcium and retinoic acid had a better degree of fat accumulation. The mRNA and protein expressions of PPARγ, C/EBPα, SREBP-1c and aP2 were analyzed and showed a significant upregulation upon the reduction in the level of extracellular calcium and retinoic acid. The upregulation of these adipogenic related genes means that the decreasing concentration of calcium and retinoic acid is able to stimulate the adipogenic differentiation of bovine intramuscular stromal vascular cells. To further elucidate the effect of calcium, the expression level of calreticulin was measured. Calreticulin which is known to be an inhibitor of PPARγ was down regulated by the decreased level of calcium and retinoic acid in the culture media. The same tendency was observed on retinoic acid receptors RARα and CRABP-II. These receptors are recognized as adipogenic inhibitors, and the downregulation of their expression allowed a better level of differentiation in bovine intramuscular stromal vascular cells. In conclusion, data show that decreasing the level of extracellular calcium and retinoic acid can significantly promote adipogenesis in intramuscular stromal vascular cells of Hanwoo beef cattle. These findings may provide new insights in enhancing intramuscular adipogenesis and marbling in beef cattle.

Keywords: calcium, calreticulin, hanwoo beef, retinoic acid

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2272 Scientific and Regulatory Challenges of Advanced Therapy Medicinal Products

Authors: Alaa Abdellatif, Gabrièle Breda

Abstract:

Background. Advanced therapy medicinal products (ATMPs) are innovative therapies that mainly target orphan diseases and high unmet medical needs. ATMP includes gene therapy medicinal products (GTMP), somatic cell therapy medicinal products (CTMP), and tissue-engineered therapies (TEP). Since legislation opened the way in 2007, 25 ATMPs have been approved in the EU, which is about the same amount as the U.S. Food and Drug Administration. However, not all of the ATMPs that have been approved have successfully reached the market and retained their approval. Objectives. We aim to understand all the factors limiting the market access to very promising therapies in a systemic approach, to be able to overcome these problems, in the future, with scientific, regulatory and commercial innovations. Further to recent reviews that focus either on specific countries, products, or dimensions, we will address all the challenges faced by ATMP development today. Methodology. We used mixed methods and a multi-level approach for data collection. First, we performed an updated academic literature review on ATMP development and their scientific and market access challenges (papers published between 2018 and April 2023). Second, we analyzed industry feedback from cell and gene therapy webinars and white papers published by providers and pharmaceutical industries. Finally, we established a comparative analysis of the regulatory guidelines published by EMA and the FDA for ATMP approval. Results: The main challenges in bringing these therapies to market are the high development costs. Developing ATMPs is expensive due to the need for specialized manufacturing processes. Furthermore, the regulatory pathways for ATMPs are often complex and can vary between countries, making it challenging to obtain approval and ensure compliance with different regulations. As a result of the high costs associated with ATMPs, challenges in obtaining reimbursement from healthcare payers lead to limited patient access to these treatments. ATMPs are often developed for orphan diseases, which means that the patient population is limited for clinical trials which can make it challenging to demonstrate their safety and efficacy. In addition, the complex manufacturing processes required for ATMPs can make it challenging to scale up production to meet demand, which can limit their availability and increase costs. Finally, ATMPs face safety and efficacy challenges: dangerous adverse events of these therapies like toxicity related to the use of viral vectors or cell therapy, starting material and donor-related aspects. Conclusion. As a result of our mixed method analysis, we found that ATMPs face a number of challenges in their development, regulatory approval, and commercialization and that addressing these challenges requires collaboration between industry, regulators, healthcare providers, and patient groups. This first analysis will help us to address, for each challenge, proper and innovative solution(s) in order to increase the number of ATMPs approved and reach the patients

Keywords: advanced therapy medicinal products (ATMPs), product development, market access, innovation

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2271 Pt Decorated Functionalized Acetylene Black as Efficient Cathode Material for Li Air Battery and Fuel Cell Applications

Authors: Rajashekar Badam, Vedarajan Raman, Noriyoshi Matsumi

Abstract:

Efficiency of energy converting and storage systems like fuel cells and Li-Air battery principally depended on oxygen reduction reaction (ORR) which occurs at cathode. As the kinetics of the ORR is very slow, it becomes the rate determining step. Exploring carbon substrates for enhancing the dispersion and activity of the metal catalyst and commercially viable simple preparation method is a very crucial area of research in the field of energy materials. Hence, many researchers made large number of carbon-based ORR materials today. But, there are hardly few studies on the effect of interaction between Pt-carbon and carbon-electrolyte on activity. In this work, we have prepared functionalized carbon-based Pt catalyst (Pt-FAB) with enhanced interfacial properties that lead to efficient ORR catalysis. The present work deals with a single-pot method to exfoliate and functionalized acetylene black with enhanced interaction with Pt as well as electrolyte. Acetylene black was functionalized and exfoliated using a facile single pot acid treatment method. The resulted FAB was further decorated with Pt-nano particles (Pt-np). The TEM images of Pt-FAB with uniformly decorated Pt-np of ~3 nm. Further, XPS studies of Pt 4f peak revealed that Pt0 peak was shifted by 0.4 eV in Pt-FAB compared to binding energy of typical Pt⁰ found in Pt/C. The shift can be ascribed to the modulation of electronic state and strong electronic interaction of Pt with carbon. Modulated electronic structure of Pt and strong electronic interaction of Pt with FAB enhances the catalytic activity and durability respectively. To understand the electrode electrolyte interface, electrochemical impedance spectroscopy was carried out. These measurements revealed that the charge transfer resistance of electrode to electrolyte for Pt-FAB is 10 times smaller than that of conventional Pt/C. The interaction with electrolyte helps reduce the interface boundaries, which in turn affects the overall catalytic performance of the electrode. Cyclic voltammetric measurements in 0.1M HClO₄ aq. at a potential scan rate of 50 mVs-1 was employed to evaluate electrochemical surface area (ECSA) of Pt. ECSA of Pt-FAB was found to be as high as 67.2 m²g⁻¹. The three-electrode system showed very high ORR catalytic activity. Mass activity at 0.9 V vs. RHE showed 460 A/g which is much higher than the DOE target values for the year 2020. Further, it showed enhanced performance by showing 723 mW/cm² of highest power density and 1006 mA/cm² of current density at 0.6 V in fuel cell single cell type configuration and 1030 mAhg⁻¹ of rechargeable capacity in Li air battery application. The higher catalytic activity can be ascribed to the improved interaction of FAB with Pt and electrolyte. The aforementioned results evince that Pt-FAB will be a promising cathode material for efficient ORR with significant cyclability for its application in fuel cells and Li-Air batteries. In conclusion, a disordered material was prepared from AB and was systematically characterized. The extremely high ORR activity and ease of preparation make it competent for replacing commercially available ORR materials.

Keywords: functionalized acetylene black, oxygen reduction reaction, fuel cells, Functionalized battery

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2270 Antioxidant Activity of Aristolochia longa L. Extracts

Authors: Merouani Nawel, Belhattab Rachid

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Aristolochia longa L. (Aristolochiacea) is a native plant of Algeria used in traditional medicine. This study was devoted to the determination of polyphenols, flavonoids, and condensed tannins contents of Aristolochia longa L. after their extraction by using various solvents with different polarities (methanol, acetone and distilled water). These extracts were prepared from stem, leaves, fruits and rhizome. The antioxidant activity was determined using three in vitro assays methods: scavenging effect on DPPH, the reducing power assay and ẞ-carotene bleaching inhibition (CBI). The results obtained indicate that the acetone extracts from the aerial parts presented the highest contents of polyphenols. The results of The antioxidant activity showed that all extracts of Aristolochia longa L., prepared using different solvent, have diverse antioxidant capacities. However, the aerial parts methanol extract exhibited the highest antioxidant capacity of DPPH and reducing power (Respectively 55,04ug/ml±1,29 and 0,2 mg/ml±0,019 ). Nevertheless, the aerial parts acetone extract showed the highest antioxidant capacity in the test of ẞ-carotene bleaching inhibition with 57%. These preliminary results could be used to justify the traditional use of this plant and their bioactive substances could be exploited for therapeutic purposes such as antioxidant and antimicrobial.

Keywords: aristolochia longa l., polyphenols, flavonoids, condensed tannins, antioxidant activity

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2269 Synthesis and Characterization of Chitosan Microparticles for Scaffold Structure and Bioprinting

Authors: J. E. Mendes, T. T. de Barros, O. B. G. de Assis, J. D. C. Pessoa

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Chitosan, a natural polysaccharide of β-1,4-linked glucosamine residues, is a biopolymer obtained primarily from the exoskeletons of crustaceans. Interest in polymeric materials increases year by year. Chitosan is one of the most plentiful biomaterials, with a wide range of pharmaceutical, biomedical, industrial and agricultural applications. Chitosan nanoparticles were synthesized via the ionotropic gelation of chitosan with sodium tripolyphosphate (TPP). Two concentrations of chitosan microparticles (0.1 and 0.2%) were synthesized. In this study, it was possible to synthesize and characterize microparticles of chitosan biomaterial and this will be used for future applications in cell anchorage for 3D bioprinting.

Keywords: chitosan microparticles, biomaterial, scaffold, bioprinting

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2268 Diagnostic Accuracy in the Detection of Cervical Lymph Node Metastases in Head and Neck Squamous Cell Carcinoma Patients: A Comparison of Sonography, CT, PET/CT and MRI

Authors: Di Luo, Maria Buchberger, Anja Pickhard

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Objectives: The purpose of this study was to assess and compare the diagnostic accuracy of four common morphological approaches, including sonography, computed tomography (CT), positron emission tomography/computed tomography (PET/CT), and magnetic resonance imaging (MRI) for the evaluation of cervical lymph node metastases in head and neck squamous cell carcinoma (HNSCC) patients. Material and Methods: Included in this retrospective study were 26 patients diagnosed with HNSCC between 2010 and 2011 who all underwent sonography, CT, PET/CT, and MRI imaging before neck dissection. Morphological data were compared to the corresponding histopathological results. Statistical analysis was performed with SPSS statistic software (version 26.0), calculating sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for detection of cervical lymph node metastases. Results: The 5-year survival rate of the patient collective was 55.5%.Risk factors for survival included initial primary tumor stage, initial lymph node stage, initial metastasis status, and therapeutic approaches. Cox regression showed initial metastasis status(HR 8.671, 95%CI 1.316-57.123, p=0.025) and therapeutic approaches(HR 6.699, 95%CI 1.746-25.700, p=0.006)to be independent predictive risk factors for survival. Sensitivity was highest for MRI (96% compared to 85% for sonography and 89% for CT and PET/CT). Specificity was comparable with 95 % for CT and 98 % for sonography and PET/CT, but only 68% for MRI. While the MRI showed the least PPV (34%) compared to all other methods (85% for sonography,75% for CT, and 86% for PET/CT), the NPV was comparable in all methods(98-99%). The overall accuracy of cervical lymph node metastases detection was comparable for sonography, CT, and PET/CT with 96%,97%,94%, respectively, while MRI had only 72% accuracy. Conclusion: Since the initial status of metastasis is an independent predictive risk factor for patients’ survival, efficient detection is crucial to plan adequate therapeutic approaches. Sonography, CT, and PET/CT have better diagnostic accuracy than MRI for the evaluation of cervical lymph node metastases in HNSCC patients.

Keywords: cervical lymph node metastases, diagnostic accuracy, head and neck squamous carcinoma, risk factors, survival

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2267 Assessing the Adaptive Re-Use Potential of Buildings as Part of the Disaster Management Process

Authors: A. Esra İdemen, Sinan M. Şener, Emrah Acar

Abstract:

The technological paradigm of the disaster management field, especially in the case of governmental intervention strategies, is generally based on rapid and flexible accommodation solutions. From various technical solution patterns used to address the immediate housing needs of disaster victims, the adaptive re-use of existing buildings can be considered to be both low-cost and practical. However, there is a scarcity of analytical methods to screen, select and adapt buildings to help decision makers in cases of emergency. Following an extensive literature review, this paper aims to highlight key points and problem areas associated with the adaptive re-use of buildings within the disaster management context. In other disciplines such as real estate management, the adaptive re-use potential (ARP) of existing buildings is typically based on the prioritization of a set of technical and non-technical criteria which are then weighted to arrive at an economically viable investment decision. After a disaster, however, the assessment of the ARP of buildings requires consideration of different/additional layers of analysis which stem from general disaster management principles and the peculiarities of different types of disasters, as well as of their victims. In this paper, a discussion of the development of an adaptive re-use potential (ARP) assessment model is presented. It is thought that governmental and non-governmental decision makers who are required to take quick decisions to accommodate displaced masses following disasters are likely to benefit from the implementation of such a model.

Keywords: adaptive re-use of buildings, disaster management, temporary housing, assessment model

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2266 Finite Element Method as a Solution Procedure for Problems in Tissue Biomechanics

Authors: Momoh Omeiza Sheidu

Abstract:

Finite element method as a method of providing solutions to problems in computational bio mechanics provides a framework for modeling the function of tissues that integrates structurally from cell to organ system and functionally across the physiological processes that affect tissue mechanics or are regulated by mechanical forces. In this paper, we present an integrative finite element strategy for solution to problems in tissue bio mechanics as a case study.

Keywords: finite element, biomechanics, modeling, computational biomechanics

Procedia PDF Downloads 488
2265 Use of Smartphone in Practical Classes to Facilitate Teaching and Learning of Microscopic Analysis and Interpretation of Tissues Sections

Authors: Lise P. Labéjof, Krisnayne S. Ribeiro, Nicolle P. dos Santos

Abstract:

An unrecorded experiment of use of the smartphone as a tool for practical classes of histology is presented in this article. Behavior, learning of the students of three science courses at the University were analyzed and compared as well as the mode of teaching of this discipline and the appreciation of the students, using either digital photographs taken by phone or drawings for record microscopic observations, analyze and interpret histological sections of human or animal tissues.

Keywords: cell phone, digital micrographies, learning of sciences, teaching practices

Procedia PDF Downloads 581
2264 Reduction of Chlordecone Rates in Bioelectrochemicals Systems from Water and Sediment Swamp Mangrove in Absence of a Redox Mediator

Authors: Malory Beaujolais

Abstract:

Chlordecone is an organochlorine pesticide with a bishomocubane structure which led to high stability in organic matter. Microbial fuel cell is a type of electrochemical system that can convert organic matters into electricity thanks to electroactive bacteria. This technique has been used with mangrove swamp from Martinique to try to reduce chlordecone rates. Those experiments led to characterize the behavior of the electroactive biofilm formed at the cathode, without added redox mediator. The designed bioelectrochemical system seems to provide the necessary conditions for chlordecone degradation.

Keywords: bioelectrochemistry, bioremediation, chlordecone, mangrove swamp

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2263 Effect of Non-Regulated pH on the Dynamics of Dark Fermentative Biohydrogen Production with Suspended and Immobilized Cell Culture

Authors: Joelle Penniston, E. B. Gueguim-Kana

Abstract:

Biohydrogen has been identified as a promising alternative to the use of non-renewable fossil reserves, owing to its sustainability and non-polluting nature. pH is considered as a key parameter in fermentative biohydrogen production processes, due to its effect on the hydrogenase activity, metabolic activity as well as substrate hydrolysis. The present study assesses the influence of regulating pH on dark fermentative biohydrogen production. Four experimental hydrogen production schemes were evaluated. Two were implemented using suspended cells under regulated pH growth conditions (Sus_R) and suspended and non-regulated pH (Sus_N). The two others regimes consisted of alginate immobilized cells under pH regulated growth conditions (Imm_R) and immobilized and non-pH regulated conditions (Imm_N). All experiments were carried out at 37.5°C with glucose as sole source of carbon. Sus_R showed a lag time of 5 hours and a peak hydrogen fraction of 36% and a glucose degradation of 37%, compared to Sus_N which showed a peak hydrogen fraction of 44% and complete glucose degradation. Both suspended culture systems showed a higher peak biohydrogen fraction compared to the immobilized cell system. Imm_R experiments showed a lag phase of 8 hours, a peak biohydrogen fraction of 35%, while Imm_N showed a lag phase of 5 hours, a peak biohydrogen fraction of 22%. 100% glucose degradation was observed in both pH regulated and non-regulated processes. This study showed that biohydrogen production in batch mode with suspended cells in a non-regulated pH environment results in a partial degradation of substrate, with lower yield. This scheme has been the culture mode of choice for most reported studies in biohydrogen research. The relatively lower slope in pH trend of the non-regulated pH experiment with immobilized cells (Imm_N) compared to Sus_N revealed that that immobilized systems have a better buffering capacity compared to suspended systems, which allows for the extended production of biohydrogen even under non-regulated pH conditions. However, alginate immobilized cultures in flask systems showed some drawbacks associated to high rate of gas production that leads to increased buoyancy of the immobilization beads. This ultimately impedes the release of gas out of the flask.

Keywords: biohydrogen, sustainability, suspended, immobilized

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2262 A Facile One Step Modification of Poly(dimethylsiloxane) via Smart Polymers for Biomicrofluidics

Authors: A. Aslihan Gokaltun, Martin L. Yarmush, Ayse Asatekin, O. Berk Usta

Abstract:

Poly(dimethylsiloxane) (PDMS) is one of the most widely used materials in the fabrication of microfluidic devices. It is easily patterned and can replicate features down to nanometers. Its flexibility, gas permeability that allows oxygenation, and low cost also drive its wide adoption. However, a major drawback of PDMS is its hydrophobicity and fast hydrophobic recovery after surface hydrophilization. This results in significant non-specific adsorption of proteins as well as small hydrophobic molecules such as therapeutic drugs limiting the utility of PDMS in biomedical microfluidic circuitry. While silicon, glass, and thermoplastics have been used, they come with problems of their own such as rigidity, high cost, and special tooling needs, which limit their use to a smaller user base. Many strategies to alleviate these common problems with PDMS are lack of general practical applicability, or have limited shelf lives in terms of the modifications they achieve. This restricts large scale implementation and adoption by industrial and research communities. Accordingly, we aim to tailor biocompatible PDMS surfaces by developing a simple and one step bulk modification approach with novel smart materials to reduce non-specific molecular adsorption and to stabilize long-term cell analysis with PDMS substrates. Smart polymers that blended with PDMS during device manufacture, spontaneously segregate to surfaces when in contact with aqueous solutions and create a < 1 nm layer that reduces non-specific adsorption of organic and biomolecules. Our methods are fully compatible with existing PDMS device manufacture protocols without any additional processing steps. We have demonstrated that our modified PDMS microfluidic system is effective at blocking the adsorption of proteins while retaining the viability of primary rat hepatocytes and preserving the biocompatibility, oxygen permeability, and transparency of the material. We expect this work will enable the development of fouling-resistant biomedical materials from microfluidics to hospital surfaces and tubing.

Keywords: cell culture, microfluidics, non-specific protein adsorption, PDMS, smart polymers

Procedia PDF Downloads 287
2261 Process Improvement and Redesign of the Immuno Histology (IHC) Lab at MSKCC: A Lean and Ergonomic Study

Authors: Samantha Meyerholz

Abstract:

MSKCC offers patients cutting edge cancer care with the highest quality standards. However, many patients and industry members do not realize that the operations of the Immunology Histology Lab (IHC) are the backbone for carrying out this mission. The IHC lab manufactures blocks and slides containing critical tissue samples that will be read by a Pathologist to diagnose and dictate a patient’s treatment course. The lab processes 200 requests daily, leading to the generation of approximately 2,000 slides and 1,100 blocks each day. Lab material is transported through labeling, cutting, staining and sorting manufacturing stations, while being managed by multiple techs throughout the space. The quality of the stain as well as wait times associated with processing requests, is directly associated with patients receiving rapid treatments and having a wider range of care options. This project aims to improve slide request turnaround time for rush and non-rush cases, while increasing the quality of each request filled (no missing slides or poorly stained items). Rush cases are to be filled in less than 24 hours, while standard cases are allotted a 48 hour time period. Reducing turnaround times enable patients to communicate sooner with their clinical team regarding their diagnosis, ultimately leading faster treatments and potentially better outcomes. Additional project goals included streamlining tech and material workflow, while reducing waste and increasing efficiency. This project followed a DMAIC structure with emphasis on lean and ergonomic principles that could be integrated into an evolving lab culture. Load times and batching processes were analyzed using process mapping, FMEA analysis, waste analysis, engineering observation, 5S and spaghetti diagramming. Reduction of lab technician movement as well as their body position at each workstation was of top concern to pathology leadership. With new equipment being brought into the lab to carry out workflow improvements, screen and tool placement was discussed with the techs in focus groups, to reduce variation and increase comfort throughout the workspace. 5S analysis was completed in two phases in the IHC lab, helping to drive solutions that reduced rework and tech motion. The IHC lab plans to continue utilizing these techniques to further reduce the time gap between tissue analysis and cancer care.

Keywords: engineering, ergonomics, healthcare, lean

Procedia PDF Downloads 217
2260 Thyroid Cancer Treatment in Yemen Under Blockade Conditions and Absence of Radioactive Iodine

Authors: Anis Al-Yakhiri

Abstract:

Introduction: The World Health Organization (WHO) classifies malignant epithelial thyroid tumors into four major groups (papillary, follicular, medullar and undifferentiated) . Papillary thyroid carcinoma (PTC) is the most common type, for about eight out of ten thyroid cancers belong to this histological type. Radioactive iodine (RAI) is considered effective for patients with total or nearly total thyroidectomy, but the beneficial effects of RAI are still controversial. War conditions forced us to study alternative methods of using radioactive iodine in the treatment of patients with PTC. Material and methods: Between January 2014 and June 2021, in Al-Yakhiri hospital, 57 Total Thyroidectomy with Radical BilateralNeckDissection (RBND) were performed, 50 for malignant disease,7 for false positive cytology.RBND involves surgical clearance of Levels II-VI. Mean age was 40.7 years old and 92% of the patients were female. 7(14%) patients had hypothyroidism which required preoperative thyroid hormone treatment. The Thyroid Stimulating Hormone- Suppression Therapy (TSH-ST) immediately started after RBND for mostpatients on the first day. It consisted in reducing the level of TSH< 0.1 mIU/L. Results: The Apron flap was used on most operations (40)80% and with lateral extensions had 10(20%). RBND involves surgical clearance of Levels II-VI performed in all operated patients, besides that, 4(8%) of them had resection of sternocleidomastoid muscle (SCM) and accessory nerve (XIn) and internal jugular vein (IJV) withclearance of Levels IB. The PTC was the most common 80.9% (38 patients from 47)by histopathological report. and 4(8%) patients of 50 had resection of sternocleidomastoid muscle (SCM) and accessory nerve (XIn) and internal jugular vein (IJV). The postoperative mortality rate not observed (0%). The postoperative morbidity rate was 22.8% (n =13).Seroma(8.7%),Hypocalcimia(7%), Wound infection(5.3%), Bleeding(1.8%). To suppress TSH and growth of any residual thyroid theTSH-ST (levothyroxine150 – 600mcg)was performed in all patients 57(100%) on the first day afterRBND. We tracked the results of treatment for two years in 30 patients with PTC, only 3 of them received radioactive iodine abroad. Biennial Recurrence rate for PTC appeared in one woman (2%), who had RAI postoperatively in the form of neck lymph nodes metastasis. Conclusion: For patients with PTC, thyroidectomy plus prophylacticRBND is a safe and efficient procedure and it results in lower recurrence rate. Postoperative treatment with exogenous thyroid hormone in doses sufficient to suppress TSH (not less than 150mcg), decreases incidence of recurrence. Total Thyroidectomy with RBND followed by TSH-ST, in our opinion, applicable optimal treatment scheme care for this patient population.

Keywords: thyroid cancer, Yemen war, absence of radioactive iodine, neck dissection, surgery results

Procedia PDF Downloads 63
2259 Investigation of Changes of Physical Properties of the Poplar Wood in Radial and Longitudinal Axis at Chaaloos Zone

Authors: Afshin Veisi

Abstract:

In this study, the physical properties of wood in poplar wood (Populous sp.) were analyzed in longitudinal and radial directions of the stem. Three Populous Alba tree were cut in chaloos zone and from each tree, 3 discs were selected at 130cm, half of tree and under of crown. The test samples from pith to bark (heartwood to sapwood) were prepared from these discs for measuring the involved properties such as, wet, dry and critical specific gravity, porosity, volume shrinkage and swelling based on the ASTM standard, and data in two radial and longitudinal directions in the trank were statistically analyzed. Such as, variations of wet, dry and critical specific gravity had in radial direction respectively: irregular increase, increase and increase, and in longitudinal direction respectively: irregular decrease, irregular increase and increase. Results of variations to moisture content and porosity show that in radial direction respectively: irregular increasing and decreasing, and in longitudinal direction from down to up respectively: irregular decreasing and stability. Volume shrinkage and swelling variations show in radial direction irregular and in longitudinal axial regular decreasing.

Keywords: poplar wood, physical properties, shrinkage, swelling, critical specific gravity, wet specific gravity, dry specific gravity

Procedia PDF Downloads 270
2258 The Effects of a Mathematics Remedial Program on Mathematics Success and Achievement among Beginning Mathematics Major Students: A Regression Discontinuity Analysis

Authors: Kuixi Du, Thomas J. Lipscomb

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The proficiency in Mathematics skills is fundamental to success in the STEM disciplines. In the US, beginning college students who are placed in remedial/developmental Mathematics courses frequently struggle to achieve academic success. Therefore, Mathematics remediation in college has become an important concern, and providing Mathematics remediation is a prevalent way to help the students who may not be fully prepared for college-level courses. Programs vary, however, and the effectiveness of a particular remedial Mathematics program must be empirically demonstrated. The purpose of this study was to apply the sharp regression discontinuity (RD) technique to determine the effectiveness of the Jack Leaps Summer (JLS) Mathematic remediation program in supporting improved Mathematics learning outcomes among newly admitted Mathematics students in the South Dakota State University. The researchers studied the newly admitted Fall 2019 cohort of Mathematics majors (n=423). The results indicated that students whose pretest score was lower than the cut-off point and who were assigned to the JLS program experienced significantly higher scores on the post-test (Math 101 final score). Based on these results, there is evidence that the JLS program is effective in meeting its primary objective.

Keywords: causal inference, mathematisc remedial program evaluation, quasi-experimental research design, regression discontinuity design, cohort studies

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2257 Exergetic Optimization on Solid Oxide Fuel Cell Systems

Authors: George N. Prodromidis, Frank A. Coutelieris

Abstract:

Biogas can be currently considered as an alternative option for electricity production, mainly due to its high energy content (hydrocarbon-rich source), its renewable status and its relatively low utilization cost. Solid Oxide Fuel Cell (SOFC) stacks convert fuel’s chemical energy to electricity with high efficiencies and reveal significant advantages on fuel flexibility combined with lower emissions rate, especially when utilize biogas. Electricity production by biogas constitutes a composite problem which incorporates an extensive parametric analysis on numerous dynamic variables. The main scope of the presented study is to propose a detailed thermodynamic model on the optimization of SOFC-based power plants’ operation based on fundamental thermodynamics, energy and exergy balances. This model named THERMAS (THERmodynamic MAthematical Simulation model) incorporates each individual process, during electricity production, mathematically simulated for different case studies that represent real life operational conditions. Also, THERMAS offers the opportunity to choose a great variety of different values for each operational parameter individually, thus allowing for studies within unexplored and experimentally impossible operational ranges. Finally, THERMAS innovatively incorporates a specific criterion concluded by the extensive energy analysis to identify the most optimal scenario per simulated system in exergy terms. Therefore, several dynamical parameters as well as several biogas mixture compositions have been taken into account, to cover all the possible incidents. Towards the optimization process in terms of an innovative OPF (OPtimization Factor), presented here, this research study reveals that systems supplied by low methane fuels can be comparable to these supplied by pure methane. To conclude, such an innovative simulation model indicates a perspective on the optimal design of a SOFC stack based system, in the direction of the commercialization of systems utilizing biogas.

Keywords: biogas, exergy, efficiency, optimization

Procedia PDF Downloads 357
2256 Intensified Electrochemical H₂O₂ Synthesis and Highly Efficient Pollutant Removal Enabled by Nickel Oxides with Surface Engineered Facets and Vacancies

Authors: Wenjun Zhang, Thao Thi Le, Dongyup Shin, Jong Min Kim

Abstract:

Electrochemical hydrogen peroxide (H₂O₂) synthesis holds significant promise for decentralized environmental remediation through the electro-Fenton process. However, challenges persist, such as the absence of robust electrocatalysts for the selective two-electron oxygen reduction reaction (2e⁻ ORR) and the high cost and sluggish kinetics of conventional electro-Fenton systems in treating highly concentrated wastewater. This study introduces an efficient water treatment system for removing substantial quantities of organic pollutants using an advanced electro-Fenton system coupled with a high-valent NiO catalyst. By employing a precipitation method involving crystal facet and cation vacancy engineering, a trivalent Ni (Ni³⁺)-rich NiO catalyst with a (111)-domain-exposed crystal facet, named {111}-NivO, was synthesized. This catalyst exhibited a remarkable 96% selectivity and a high mass activity of 59 A g⁻¹ for H₂O₂ production, outperforming all previously reported Ni-based catalysts. Furthermore, an advanced electro-Fenton system, integrated with a flow cell for electrochemical H₂O₂ production, was utilized to achieve 100% removal of 50 ppm bisphenol A (BPA) in 200 mL of wastewater under heavy-duty conditions, reaching a superior rapid degradation rate (4 min, k = 1.125 min⁻¹), approximately 102 times faster than the conventional electro-Fenton system. The hyper-efficiency is attributed to the continuous and appropriate supply of H₂O₂, the provision of O₂, and the timely recycling of the electrolyte under high current density operation. This catalyst also demonstrated a 93% removal of total organic carbon after 2 hours of operation and can be applied for efficient removal of highly concentrated phenol pollutants from aqueous systems, which opens new avenues for wastewater treatment.

Keywords: hydrogen peroxide production, nickel oxides, crystal facet and cation vacancy engineering, wastewater treatment, flow cell, electro-Fenton

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2255 Effect Of Tephrosia purpurea (Family: Fabaceae) Formulations On Oviposition By The Pulse Beetle Callosobruchus chinensis Linn.

Authors: Priyanka Jain, Meera Srivastava

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Among important insect pests of stored grains, the pulse beetle Callosobruchus chinensis Linn. (Coleoptera: Bruchidae) is one such pest causing considerable damage to stored pulses. An effort was made to screen plant Tephrosia purpurea (Family: Fabaceae) for its efficacy against the said pest. The pulse beetle C. chinensis was raised on green gram Vigna radiata in incubators maintained at 28 ± 2°C and 70% RH. Different formulations using plant parts (root, stem, leaf and fruit) were employed in the form of aqueous suspension, aqueous extract and ether extract and the treatments were made using different dose concentrations, namely 1%, 2.5%, 5% and 10%, besides normal and control. Specific number of adult insects were released in muslin cloth covered beakers containing weighed green gram grains and treated with different dose concentrations (w/v). Observations for the number of eggs laid by the pest insect C. chinensis was recorded after three days of treatment and it was observed that in general all the treatments of the plant resulted in significant decrease in the eggs laid (no/pair) by the insect, suggesting that the selected plant has a potential to be used against C. chinensis.

Keywords: Callosobruchus chinensis, egg laying, Tephrosia purpurea, Fabaceae, plant formulations

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2254 Identification of Tissue-Specific Transcription Factors in C. roseus with Emphasis to the TIA Biosynthetic Pathway

Authors: F. M. El-Domyati, A. Atef, S. Edris, N. O. Gadalla, M. A. Al-Kordy, A. M. Ramadan, Y. M. Saad, H. S. Al-Zahrani, A. Bahieldin

Abstract:

Transcriptome retrieved from SRA database of different tissues and treatments of C. roseus was assembled in order to detect tissue-specific transcription factors (TFs) and TFs possibly related to terpenoid indole alkaloids (TIA) pathway. A number of 290 TF-like transcripts along with 12 transcripts related to TIA biosynthetic pathway were divided in terms of co-expression in the different tissues, treatments and genotypes. Three transcripts encoding peroxidases 1 and 12 were downregulated in hairy root, while upregulated in mature leaf. Eight different transcripts of the TIA pathway co-expressed with TFs either functioning downstream tryptophan biosynthesis, e.g., tdc, str1 and sgd, or upstream vindoline biosynthesis, e.g., t16h, omt, nmt, d4h and dat. The results showed no differential expression of TF transcripts in hairy roots knocked down for tdc gene (TDCi) as compared to their wild type controls. There were several evidences of tissue-specific expression of TF transcripts in flower, mature leaf, root/hairy root, stem, seedling, hairy root and immature/mature leaves. Regulation included transcription factor families, e.g., bHLH, MYB and WRKY mostly induced by ABA and/or JA (or MeJA) and regulated during abiotic or biotic stress. The information of tissue-specific regulation and co-expression of TFs and genes in the TIA pathway can be utilized in manipulating alkaloid biosynthesis in C. roseus.

Keywords: SRA database, bHLH, MYB, WRKY, co-expression

Procedia PDF Downloads 400