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Impact of Biogenic Amines on the Growth of Green Microalgae
Get PDFBackground: The goal of this research project was to test various neuroactive amines in the capacity of growth stimulators/accelerators of the green microalgae Scenedesmus quadricauda and Chlorella vulgaris that have much biotechnological potential because they can be used for producing drugs, food ingredients, cosmetics, and biofuel. The issue of the ecological role of the biogenic amines in terms of interspecies communication in aqueous ecosystems was also addressed in this work.
Methods: S. quadricauda strain GEHD and C. vulgaris strain ALP were cultivated in the light with constant aeration at 24oC in a minerals-containing medium. Experimental systems contained 1, 10 or 100 mM of dopamine hydrochloride, histamine hydrochloride, norepinephrine hydrochloride, or serotonin hydrochloride that were added at inoculation as freshly prepared aqueous solutions. Algal cells were counted using a light microscope , and their number in 1 mL of culture was calculated. The culture liquid and sonicated biomass of S. quadricauda and C. vulgaris were tested for the presence of endogenous amines using high-performance liquid chromatography (HPLC) with an amperometric detector.
Results: The biogenic amines serotonin, norepinephrine, dopamine, and histamine significantly stimulated the growth of S. quadricauda, at concentrations of 1 and/or 10 mM but not 100 mM. Histamine was the most efficient stimulator, causing an average 65% increase in biomass accumulation at the end of the cultivation period. The effects of serotonin, dopamine and histamine on C. vulgaris were reported in our previous publication [1], but this work contains the results of our experiments with the previously untested norepinephrine that slightly stimulated the growth of C. vulgaris. HPLC analysis failed to reveal any endogenous amines in the culture liquid and biomass of both microalgae.
Conclusions: Since biogenic amines stimulate the growth of the microalgae S. quadricauda and C. vulgaris but are not synthesized by them, we suggest that the algae normally respond to amines produced by other components of aqueous ecosystems, including zooplankton and fish that are known to release significant amounts of biogenic amines into the environment. The data obtained hold some promise with regard to developing a relatively economical technique of boosting algal biomass production
Use of Over-the-Counter Products in Lebanese Adults with Cardiovascular Disease
Get PDFBackground: While selling over-the-counter (OTC) products in pharmacies is convenient to individuals and can be beneficial, it might potentially cause harm. We hereby describe the patterns of OTC product consumption amongst adults with cardiovascular disease (CVD) in Lebanon and the potential interactions with prescription medications and patient diseases.
Methods: This was a cross-sectional study in the setting of nine community pharmacies across different governorates of Lebanon. Data of interest were collected from adult patients with CVD history through face-to-face interviews using a short questionnaire.
Results: Out of 201 adult patients included in the study, 190 (94.5%) were using at least one OTC product, with a mean of 3.2 ± 2.4 per patient (range of 1 to 12 products). The proportion of patients taking analgesics was the greatest (81.1%), followed by those taking vitamins (48.8%), minerals (29.9%), and herbal products (13.9%). Several potentially harmful OTC product- drug or -disease interactions were identified. Only 65.3% of OTC users reported obtaining information about the used products from healthcare professionals (HCPs), and 35.3% did not disclose the use of the products to their HCPs.
Conclusion: The use of OTC products was highly prevalent among patients with CVD with potential interactions with prescription medications and patient diseases. In order to ensure optimal patient outcomes, clinicians are strongly encouraged to inquire about OTC product use and counsel patients about the risks and benefits associated with such products
Arbuscular Mycorrhizal Colonization in Five Tropical Forest Tree Legumes of Chittagong University Campus in Bangladesh
Get PDFArbuscular mycorrhizal (AM) colonization in five tropical forest tree legumes (Gliricidia sepium, Dalbergia sissoo, Indigofera tysmanii, Delonix regia and Samanea saman) was investigated in Chittagong University (CU) campus. The results of the present study clearly suggests that, Vesicular AM fungi (VAM) are common in all the studied forest tree species, and that the studied forest tree species differ in their rates of AM formation. The intensity of colonization is maximum (98%) in I. tysmonii followed by D. sissoo (95%), D. regia (63%), S. saman (59%) and G. sepium (52%). Coiled structures of hyphae were recorded in D. regia. Arbuscule formation was recorded in D. sissooand in I. tysmonii. Mycorrhizal spores were found in rhizosphere soils of all the sites. Glomus, Acaulospora, Entrophospora and Gigaspora spores were identified in all the hosts. Forest plants differ in their rates of AM formation. Edhapic conditions like moisture content, soil pH also influence the extent of root colonization.Keyword: Mycorrhizae, Legume, Colonization, Edhapic condition, Rhizosphere, Underground networking
Some New Exact Solutions for Prescribed Vorticity Distribution of Couple Stress Fluids in the Presence of Unknown Body Force
Get PDFIn the present paper, we indicate some new exact solutions of equations of motion for plane steady incompressible couple stress fluids flows in the presence of unknown body force for which vorticity distribution is defined by Eq. (12). All solutions involve arbitrary real constants and arbitrary real constants depending on the parameter èindicating that a large number of streamfunctions and expressions for body force can be constructed. Some streamfunctions ø are constructed for some values of parameters. The streamlines patterns of these streamfunctions are presented and discussed
Impact of Nano-FeS2 Layer on the Stability Performance of CdS-Cu2O PV Cells: A Study
Get PDFThe presence of nano-structured FeS2 film at the junction of CdS-Cu2O thin film PV cells demonstrated long term stability in its performances. The CdS layer was fabricated by vacuum evaporation technique and its top surface was converted to FeS2 by dipping in hot FeCl2 solution. The Cu2O was deposited over it by plasma deposition process. A thin Ni-Au layer was deposited over the Cu2O surface by an electroless deposition process to act as the top electrical contact. The cell properties and its stability were studied under external stresses including heat and light. The cells efficiency attained 2.35% at AM1 illumination. The fabricated cells were tested under thermal cycling and light soaking and their performances were compared with other cells like Si, CdTe and CIS. Results showed that the CdS-Cu2O device with FeS2 is more stable than the other cells. From these results it was concluded that the nano FeS2 layer made perfect matching with n-CdS and p-Cu2O due to its strong inversion and yields both bulk electrons and surface holes. Moreover, the hardness of the FeS2 layer puts barriers that slow the inter-diffusion / migration of Cu ions into the bulk CdS thus preventing the formation of Cu-Cd killer centres
Potential of Chromolaena odorata and Indigenous Bacterial Consortium for Oily Wastewater Treatment
Get PDFThis study was carried out to investigate the possibility of using Chromolaena odorata as absorbent and to ascertain as to whether indigenous bacteria has the potential to degrade hydrocarbon from oily wastewater and thereby reducing its toxicity and other negative impacts to the environment particularly on aquatic life. The potential of Chromolaena odorata and indigenous bacteria to remove oil from wastewater was evaluated by measuring total suspended solid (TSS) concentration. The result shows that, about 55% of oil substances were absorbed or removed after 4 hours of Chromolaena odorata application with the optimum dosage of 4mg/L. Growth percentage of bacterial consortium and single pure strain on medium containing oily wastewater was studied. It was found that bacterial consortium, the mixture of Bacillus cereus (KA) and Acinetobacter (TB) shows higher growth among other bacterial consortium and single pure cultures and this consortium was used for further analysis. In addition, the results have shown that, bacterial consortium (KA+TB) exhibited high efficiency to remove TSS at the optimum dosage of 1 mg/L. Absorption and biodegradation rate was increased after being treated with Chromolaena odorata and bacterial consortium mixture. The mixture of Chromolaena odorata powder and bacterial consortium in 4:1 ratio was obtained to significantly removed TSS by 75% in 24 hours
Perception of the Extension Agents Regarding Information Sources of Sustainable Agriculture in Sindh Province of Pakistan
Get PDFThe study was undertaken in Sindh province to examine the extension agents perceptions of various sources of information. This study used a descriptive research design and the target population was Extension Agents. A representative sample of 162 Extension agents was proposed from six districts of Sindh, namely, 1. Larkana 2. Naushehro Feroze 3. Shaheed Benazirabad 4. Sanghar 5. Mirpurkhas 6. Badin representing the agro-ecological zones of Sindh province. The majority of the respondents 49.38% having their age in the range of 31-45 years. The data revealed that majority of the extension personnel 43.21% of the respondents were graduate level of education. The diploma holder\u27s respondents were 24.69%. The majority of the extension personnel (43.21%) had job experience 21-30 years. Only 6.17% of the extension personnel had job experience of more than 31 years. The most frequent sources of information was perceived by extension agents about sustainable agriculture were television broadcasts,. However, Internet / Computers, Books and Manuals, Middle Man, and Electronic Devices (Mobile, Fax and other sources). The majority of the respondents perceived that Lack of effective monitoring (reporting and supervision) (M=1.26, SD=.058), Lack of Linkage between Research and Extension (M=1.06, SD=.025), Shortage of time to teach farmer properly (M=1.21, SD=.042), Illiteracy among farmers (M=1.141, SD=.061) and Lack of transportation facilities (M=1.21, SD=.042)as higher barrier that hampering the promotion and adoption of sustainable agriculture practices in the areas where they worked, this implies that proper guidelines and teaching aids had not been given to the extension worker to effectively work and communicate with the local farmer. However in sufficient funding for agriculture extension (M=1.71, SD=.061 Lack of means for upgrading qualification M=1.93, SD=.048), Large farm area (M=1.85, SD=.065), Lack of In-service Courses M=2.00, SD=.040), More time and management M=2.00, SD=.000) and Lack of Information about Sustainable Agriculture Technologies M=2.00, SD=.000) were perceived as a low barrier in adoption of sustainable agriculture practices.. This study will enable policy makers to effectively transfer the technology for sustained growth and will enhance farmers understanding about the concept of sustainable agriculture
Fragmentation Analysis For Scalable Wireless Local Area Networks
Get PDFWireless networks are being deployed widely to provide network connectivity without requiring the web of physical wires. A collection of a small number of workstations connected using a wireless network forms a wireless local area network (WLAN) that follows the IEEE 802.11 standard. In a WLAN, the communication takes place using packets whose sizes may vary and have a significant impact on the delay incurred during transmission. In this regard, fragmentation may play a vital role in reducing the delay for efficient transmission across the network. This paper analyzes the performance of WLANs with respect to the packet fragmentation. We simulate three network scenarios having 4, 8 and 12 wireless workstations respectively. The scenarios are simulated using OPNET IT Guru Academic Edition v 9.1 while incorporating a peer-to-peer (P2P) based communication model for each scenario. We compare the performance of non-fragmented and fragmented communication in terms of network delay and throughput. Our results show that the fragmentation minimizes the delay and increases the throughput, however its impact is highly dependent on the size of the underlying network
Calculation of the Relaxation Time and the Activation Energy Close to the Lower Phase Transition in Imidazolium Perchlorate
Get PDFThe temperature dependence of the relaxation time of imidazolium perchlorate (Im-ClO4) was calculated from the pseudospin-phonon coupled (PS) and the energy fluctuation (EF) models close to the first-order phase transition temperature of 247 K. This calculation was performed in terms of the proton second moment M2 that was associated with the order parameter which was predicted from the mean-field theory. Our results were in good agreement with the observed data. In addition, values of the activation energy were deduced in terms of the Arrhenius plot using our calculated values of the relaxation time from both PS and EF models
A Survey of the Relationship Between Serum Cholesterol and Triglyceride to Glaucoma: A Case Control Study
Get PDFPurpose/Aim: primary Open-angle glaucoma (POAG) is an asymptomatic, progressive optic neuropathy characterized by enlarging optic disc cupping and visual field loss. POAG is a major cause of blindness and is characterized by progressive degeneration of the optic nerve and is usually associated with elevated intraocular pressure. Regarding the fact that dyslipidemia has a relationship with some ophthalmic diseases such as cataract,it sounds that the same relationship also exists with POAG. Therefore, it was decided to study the relationship between serum cholesterol and triglyceride to POAG.
Methods: The present study was done on 40 primary Open-angle glaucoma (POAG) patients (cases) and 40 healthy individuals (controls). In order to diagnose POAG, Intra ocular pressure (IOP) was measured by means of Applanation tonometry, and then was confirmed through perimetry and ophthalmoscopes. The controls were patients’ attendants who had referred to Birjand Valli-e-asr clinics but did not have POAG. After a fasting of 12 hours, blood samples were derived to determine serum level of triglyceride and cholesterol levels. Then, the results of the tests together with the participants’ demographic information were individually registered in a questionnaire. The obtained data was analyzed by means of SPSS software (version 15) and statistical tests including T-test and Chi- square.
Results: Mean levels of cholesterol (211.18± 51.91mg/dl in cases, 162.38±39.56 mg/dl in controls) and triglyceride (165.92±88.58 mg/dl in cases, 99.46± 43.08 mg/dl in control) were significantly higher in cases than in controls. Hypercholesterolemia and hypertriglyceridemia were significantly higher in the cases compared with the controls. There was a positive association between POAG and dyslipidemia (OR=7.14 [95% CI: 2.3-22.2] for Hypercholesterolemia and OR=16.9 [95% CI: 2.1-14.8] for hypertriglyceridemia.
Conclusion: Hyperlipidemia can be a risk factor of getting POAG