1,640 research outputs found
Hepatotoxicity of Microcystis aeruginosa Strains Growing as Blooms in Certain Eutrophic Ponds
Critical assessment of five eutrophicated ponds of Varanasi city (India) revealed the presence of heavy blooms of cyanobacteria consisting mainly of Microcystis aeruginosa. Crude aqueous extracts of blooms as well as laboratory grown M. aeruginosa isolated from three ponds, namely Lakshmikund, Durgakund and Adityanagar showed toxicity in mouse bioassay test. Crude aqueous extracts from these samples caused death of test mice within 1h of administration (i.p.) with a LD50 of 60 mg/kg body weight and the treated animals showed clinical signs of hepatotoxicity. However such an effect was not associated with the blooms from Laatbhairov and Surajkund ponds suggesting that not all strains of M. aeruginosa are toxic. Based on spectral properties (?max 230 nm), and comparison with standard microcystin-LR, the toxin is tentatively identified as microcystin-LR. The purified toxin caused death of test mice within 40 min of its administration with a LD50 of 100 µg/ kg body weight and induced gross morphological and functional changes in liver. A 1.55 fold increase in liver weight accompanied by deep red coloration most probably due to hemorrhage and blood pooling suggested the hepatotoxic properties of the toxin. Hepatotoxicity was also evident from the drastic increase (up to 2.5 fold) in activity of serum enzymes such as glutamate pyruvate transaminase/alanine aminotransferase (GPT/ALT), lactate dehydrogenase (LDH) and alkaline phosphatase (APase) following toxin treatment. ^14C-labelling experiments demonstrated maximum accumulation (~15%) of ^14C- toxin after 20 min. of toxin administration. Appreciable level of toxin was also detected in water of four ponds. In conclusion these results clearly demonstrate that microcystin-producing blooms of M. aeruginosa are common in eutrophicated ponds of Varanasi city but not all ponds harbour toxic blooms
Molecular Mechanisms of Ultraviolet Radiation-Induced DNA Damage and Repair
DNA is one of the prime molecules, and its stability is of utmost importance for proper functioning and existence of all living systems. Genotoxic chemicals and radiations exert adverse effects on genome stability. Ultraviolet radiation (UVR) (mainly UV-B: 280–315 nm) is one of the powerful agents that can alter the normal state of life by inducing a variety of mutagenic and cytotoxic DNA lesions such as cyclobutane-pyrimidine dimers (CPDs), 6-4 photoproducts (6-4PPs), and their Dewar valence isomers as well as DNA strand breaks by interfering the genome integrity. To counteract these lesions, organisms have developed a number of highly conserved repair mechanisms such as photoreactivation, base excision repair (BER), nucleotide excision repair (NER), and mismatch repair (MMR). Additionally, double-strand break repair (by homologous recombination and nonhomologous end joining), SOS response, cell-cycle checkpoints, and programmed cell death (apoptosis) are also operative in various organisms with the expense of specific gene products. This review deals with UV-induced alterations in DNA and its maintenance by various repair mechanisms
A Self Learning based Diagnosis of Faulty Configurable Logic Blocks (CLBs) in Field Programmable Gate Arrays (FPGA) Using Reconfiguration
In many areas of digital systems Field programmable gate arrays (FPGAs) are most important for designing. The main usesof FPGAs are, these are programmable, and faults can be easily diagnosed, once faulty locations are identified. The locationand identification of faults in FPGA has not yet been explored much. A methodology for the testing and diagnosis of faultsin FPGAs is presented based on automatic circuit reconfiguration. The proposed method imposes no hardware overhead.This method can also be used in fault-tolerant systems, in which a good functional circuit can be still mapped to a FPGAwith faulty elements, as long as the fault sites are known. The logic synthesis software assigns the Configurable Logic Block(CLB) resources without system designer intervention. It is very advantageous for the designer to understand certain CLBdetails, including the varying capabilities of the look-up tables (LUTs), the physical direction of the carry propagation, thenumber and distribution of the available flip-flops. FPGA consists of 25 Configurable Logic Blocks (CLB). Each CLB isassigned with an application. The inputs for CLB are applied from a file. There is also a fault file in which error CLBs arepresent. If there is error CLBs, those CLBs are replaced by the spare CLBs. Finally, the errors CLBs are corrected withproper inputs and modified bits are displayed. So efficiency is not reduced and configurability is done without replacing thefaulty components. This FPGA can tolerate not only single faults but also for multiple faults. The power analysis resultsprovided for fault free, stuck-at-1, stuck-at-0 faults in digital circuits validate the point that faulty circuits dissipates moreand hence draw more power.Key words: Configurable Logic Block (CLB), Power Dissipation, Fault Tolerance, Fault Diagnosis, Faults, Full adder (FA)
Photoelectrochemical Cell Including Ga(Sb\u3csub\u3ex\u3c/sub\u3e)N\u3csub\u3e1-x\u3c/sub\u3e Semiconductor Electrode
The composition of matter comprising Ga(Sbx)N1−x where x=0.01 to 0.06 is characterized by a band gap between 2.4 and 1.7 eV. A semiconductor device includes a semiconductor layer of that composition. A photoelectric cell includes that semiconductor device
Not Available
Not AvailableGillnets are commonly used in inland lakes due to
their simplicity in construction and operation,
efficiency, and low energy usage. The Vembanad
lake is one of the most prominent lakes in Kerala,
contributing significantly to the small-scale and
artisanal fisheries, in which gillnets are the predominant
gear. There have been studies on the effect of
gillnet panel colour on the selective capture of fish
species, primarily in the open ocean and rivers.
Although a considerable number of studies exist on
the species profile and fish catching methods in the
lake, the efficiency of coloured webbing for gillnets
is not available. The efficiency of coloured webbing
for gillnets is not documented, which, if available,
would be a crucial input for implementing gearbased
technical measures for conservation in gillnets
in the lake. In this regard, a study was conducted
along Vembanad lake and the lower reaches of the
Muvattupuzha river to compare the catch efficiency
and species profile of transparent gillnets typically
employed in the region with gillnets fabricated
using blue and green coloured webbing. The results
demonstrated a considerable increase in CPUE for
green-coloured gillnets (708.9±12.8 grams per operation)
compared to blue and transparent gillnets,
which had CPUE values of 397.9±80.2 and 293.7±70.6
grams per operation, respectively. Significantly
higher catches of Horabagrus brachysoma and Etroplus
suratensis were obtained with the green-coloured
gillnets than with the control (Transparent). Lengthwise
data showed that green-coloured nets captured
larger individuals of E. suratensis, but significant
difference was not observed in other species. The number of E. suratensis captured in each gillnet
contributed to the most dissimilarity in all comparisons,
followed by Gerres sp. and H. brachysoma,
according to similarities percentage analysis conducted
to comprehend the species assemblage
structure. This is the first report on the effect of
gillnet colour on the catch efficiency of gillnets in
Vembanad lake, and the results, which indicate
species-specific differences in capture, will be one
of the many inputs necessary for implementing
gear-based technical measures in the gillnet fishery
in the lake.Not Availabl
Spontaneous urinary bladder perforation as a cause of recurrent, progressive ascites with multiorgan dysfunction syndrome
Spontaneous rupture of the urinary bladder wall is a rare complication that may lead to intraperitoneal accumulation of urine and is mistaken for ascites from other causes. This often leads to repeated and inconclusive diagnostic tests. Here, we report the case of a 60-year-old female, with a past history of cervical cancer, who presented with recurrent episodes of pain abdomen and breathlessness over 1 year period. She was hospitalized multiple times and found to have ascites. Ultrasound and computed tomography scan of the abdomen along with an ascitic fluid analysis were done at each admission, which were inconclusive as to the cause of the ascites. A diagnostic laparoscopy to rule out peritoneal metastases showed perforation of the urinary bladder wall with intraperitoneal urine leakage. Bladder wall repair was done the following which the patient recovered uneventfully
Demarcation of Ground Water Potential Zones using Remote Sensing and GIS Applications
Now-a-days, due to the high demand of water for the human needs, groundwater sources are drastically extracted and causing to least the source. The entire Yearly furnish is contributing from the utmost resource called Groundwater. Globally, groundwater is extracting primarily for the purpose of agricultural fields, domestic and for industrial water supply. Majority of the surface water is in the form of saline water which is not useful for the needs of human beings for their daily needs. Very less amount of fresh surface water is existing on the ground surface. To compensate the needs, it is essential to identify, extract and manage the groundwater which is available at different levels at different areas of the globe. Proper planning is required for the extraction of groundwater using updated technologies for using and maintaining of natural resources like water resources. The prime strive of the selected project area is to map out potential groundwater regions in the Pendlimarri Mandal of Kadapa District by using Geospatial Technology. The main impartial target of the work is to select appropriate methods and assessment criteria of the technology to identify the potential underground demarcations in geographic information system environment with help of ArcGIS software. To demarcate zones of groundwater potential, various key parameters called geology, lineament density, LU / LC, geomorphology, groundwater depths, slope and drainage pattern were prepared by utilizing remote sensing data and secondary data which can collect from concern departments. The thematic layers are to be finally integrated by using weighted overlay analysis of spatial analyst tools of data management tools of ArcMap software to delineate underground water prospects regions output layout of the project. Disparate groundwater prospects levels were categorized, from the range excellent to poor including very good, good and moderate in between. At last, decided that that the applications of geoinformatics are essential and effectively applied for the demarcation of potential zones of groundwater
Analysis and Classification of Breast Cancer Disease Via Different Datasets and Classifier Models
Nowadays, Tumour is one of the important reasons of human death worldwide, producing about 9.6 million people in 2018. BC (breast cancer) is the common reason for cancer deaths in females. BC is a type of cancer that can be treated when detected early. The main motive of this analysis is to detect cancer early in life using ML (machine learning) techniques. The features of the people included in the WDBC (Wisconsin diagnostic breast cancer) and Coimbra BC datasets were classified by SVOF-KNN, KNN, and Naïve Bayes techniques. The pre-processing data phase was applied to the datasets before classification. After the data pre-processing steps, three classification methods were applied to the data. Specificity and Sensitivity rates were used to calculate the success of the techniques. As an outcome of the BC diagnosis classification, the SVOF-KNN technique was found with a 91 percent specificity rate and 90 percent sensitivity rate. When the outcomes attained from feature extraction and selection are calculated. It is seen that feature extraction, selection, and data pre-processing techniques improve the specificity and sensitivity rate of the detection system
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