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1.
Int J Med Inform ; 165: 104831, 2022 09.
Article in English | MEDLINE | ID: mdl-35870303

ABSTRACT

The chest X-ray is a widely used medical imaging technique for the diagnosis of several lung diseases. Some nodules or other pathologies present in the lungs are difficult to visualize on chest X-rays because they are obscured byoverlying boneshadows. Segmentation of bone structures and suppressing them assist medical professionals in reliable diagnosis and organ morphometry. But segmentation of bone structures is challenging due to fuzzy boundaries of organs and inconsistent shape and size of organs due to health issues, age, and gender. The existing bone segmentation methods do not report their performance on abnormal chest X-rays, where it is even more critical to segment the bones. This work presents a robust encoder-decoder network for semantic segmentation of bone structures on normal as well as abnormal chest X-rays. The novelty here lies in combining techniques from two existing networks (Deeplabv3+ and U-net) to achieve robust and superior performance. The fully connected layers of the pre-trained ResNet50 network have been replaced by an Atrous spatial pyramid pooling block for improving the quality of the embedding in the encoder module. The decoder module includes four times upsampling blocks to connect both low-level and high-level features information enabling us to retain both the edges and detail information of the objects. At each level, the up-sampled decoder features are concatenated with the encoder features at a similar level and further fine-tuned to refine the segmentation output. We construct a diverse chest X-ray dataset with ground truth binary masks of anterior ribs, posterior ribs, and clavicle bone for experimentation. The dataset includes 100 samples of chest X-rays belonging to healthy and confirmed patients of lung diseases to maintain the diversity and test the robustness of our method. We test our method using multiple standard metrics and experimental results indicate an excellent performance on both normal and abnormal chest X-rays.


Subject(s)
Image Processing, Computer-Assisted , Lung Diseases , Humans , Image Processing, Computer-Assisted/methods , Radiography , Semantics , X-Rays
2.
Dalton Trans ; 50(42): 15071-15083, 2021 Nov 02.
Article in English | MEDLINE | ID: mdl-34610074

ABSTRACT

Controlling the valence mixing of Eu3+/Eu2+ and energy transfer between activator ions in solid solution is an important process to improve the efficiency and specificity of phosphors. In this work, the structural and optical properties of stillwellite type SrBPO5 doped with uranium/europium/samarium, as prepared by conventional solid-state reaction synthesis, were investigated. PXRD studies and Rietveld analysis were carried out to determine the structure, phase purity, and coordination environment of the dopants in the host matrix. Samarium existed only as a trivalent cation in SrBPO5 synthesised in an air atmosphere, whereas europium exhibited abnormal reduction and Eu2+ co-existed with Eu3+. Unlike Eu and Sm, which replaced Sr at its sites, uranium gets stabilised as UO22+ in the interstitial vacant space in the SrBPO5 lattice. Uranium co-doping strongly influenced the Eu valence distribution by favouring the re-oxidation of Eu2+ to Eu3+. Possible mechanisms of Eu abnormal reduction in SrBPO5 and Eu valence control based on the electron transfer from substitutional Eu2+ to interstitial UO22+ are discussed. The photoluminescence and time-resolved photoluminescence properties of Eu/Sm/U doped SrBPO5 were investigated systematically. Uranium co-doping significantly enhanced the emission intensities of trivalent Eu and Sm through the exchange-type energy transfer. Besides, the Eu3+ luminescence intensity was further amplified in the presence of uranium due to the partial oxidation of Eu2+ to Eu3+. By controlling the uranium to Eu concentration ratio, the Eu-SrBPO5 phosphor could be tuned to different CIE coordinates.

3.
J Med Biol Eng ; 41(5): 678-689, 2021.
Article in English | MEDLINE | ID: mdl-34483791

ABSTRACT

Purpose: In early 2020, the world is amid a significant pandemic due to the novel coronavirus disease outbreak, commonly called the COVID-19. Coronavirus is a lung infection disease caused by the Severe Acute Respiratory Syndrome Coronavirus 2 virus (SARS-CoV-2). Because of its high transmission rate, it is crucial to detect cases as soon as possible to effectively control the spread of this pandemic and treat patients in the early stages. RT-PCR-based kits are the current standard kits used for COVID-19 diagnosis, but these tests take much time despite their high precision. A faster automated diagnostic tool is required for the effective screening of COVID-19. Methods: In this study, a new semi-supervised feature learning technique is proposed to screen COVID-19 patients using chest CT scans. The model proposed in this study uses a three-step architecture, consisting of a convolutional autoencoder based unsupervised feature extractor, a multi-objective genetic algorithm (MOGA) based feature selector, and a Bagging Ensemble of support vector machines based binary classifier. The proposed architecture has been designed to provide precise and robust diagnostics for binary classification (COVID vs.nonCOVID). A dataset of 1252 COVID-19 CT scan images, collected from 60 patients, has been used to train and evaluate the model. Results: The best performing classifier within 127 ms per image achieved an accuracy of 98.79%, the precision of 98.47%, area under curve of 0.998, and an F1 score of 98.85% on 497 test images. The proposed model outperforms the current state of the art COVID-19 diagnostic techniques in terms of speed and accuracy. Conclusion: The experimental results prove the superiority of the proposed methodology in comparison to existing methods.The study also comprehensively compares various feature selection techniques and highlights the importance of feature selection in medical image data problems.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 253: 119560, 2021 May 15.
Article in English | MEDLINE | ID: mdl-33621932

ABSTRACT

A single-component white-light emitting phosphor SrBPO5: Ce3+, Dy3+ with high color purity, good quantum efficiency and high thermal stability was prepared through the conventional high temperature solid state reaction. PXRD studies confirmed its phase purity. The suitability of Strontium borophosphate as a host for phosphor was confirmed through DFT calculations. The presence of Ce3+ along with Dy3+ in this host resulted in efficient energy transfer from Ce3+ to Dy3+ through a non-radiative multipole-multipole mechanism leading to the enhancement of Dy3+ luminescence towards white light emission. Lifetime decay and time-resolved emission studies confirmed the energy transfer along with multisite occupancy of Ce3+. In addition to energy transfer, the thermal stability of the phosphor was confirmed through temperature-dependent photoluminescence studies and the particle shape, size, uniformity of dopants of the phosphor was studied using the SEM and EDX spectroscopy.

5.
J Med Syst ; 44(2): 34, 2019 Dec 18.
Article in English | MEDLINE | ID: mdl-31853735

ABSTRACT

Computer assisted automatic smart pattern analysis of cancer affected pixel structure takes critical role in pre-interventional decision making for oral cancer treatment. Internet of Things (IoT) in healthcare systems is now emerging solution for modern e-healthcare system to provide high quality medical care. In this research work, we proposed a novel method which utilizes a modified vesselness measurement and a Deep Convolutional Neural Network (DCNN) to identify the oral cancer region structure in IoT based smart healthcare system. The robust vesselness filtering scheme handles noise while reserving small structures, while the CNN framework considerably improves classification accuracy by deblurring focused region of interest (ROI) through integrating with multi-dimensional information from feature vector selection step. The marked feature vector points are extracted from each connected component in the region and used as input for training the CNN. During classification, each connected part is individually analysed using the trained DCNN by considering the feature vector values that belong to its region. For a training of 1500 image dataset, an accuracy of 96.8% and sensitivity of 92% is obtained. Hence, the results of this work validate that the proposed algorithm is effective and accurate in terms of classification of oral cancer region in accurate decision making. The developed system can be used in IoT based diagnosis in health care systems, where accuracy and real time diagnosis are essential.


Subject(s)
Decision Support Systems, Clinical/standards , Internet of Things , Mouth Neoplasms/classification , Mouth Neoplasms/diagnostic imaging , Neural Networks, Computer , Algorithms , Deep Learning , Diagnosis, Computer-Assisted/methods , Humans
6.
Luminescence ; 34(8): 887-894, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31328361

ABSTRACT

Ce-doped (1 × 10-5 to 3.0 mol%) SrBPO5 phosphors were synthesized using a conventional solid-state reaction route at 1273 K in an air atmosphere. Phase and morphology of the samples were studied from powder X-ray diffraction (XRD) patterns and scanning electron microscope (SEM) micrographs, respectively. The band gap energies of the pure and Ce-doped SrBPO5 phosphors were calculated from the recorded diffuse reflectance spectra. Photoluminescence (PL) and Ce3+ lifetime were recorded at 300 and 77 K. Photoluminescence lifetime measurements revealed two-lifetime values for Ce3+ at both 300 K (17 and 36 nsec) and 77 K (12 and 30 nsec), suggesting the presence of two different environments around Ce3+ . Time-resolved emission spectroscopy (TRES) studies confirmed the presence of Ce3+ in two different environments. In addition, SrBPO5 :Ce exhibited intense UV emission, signifying its possible use as an efficient sensitizer for solid-state lighting applications. The effect of γ-irradiation on PL was also determined. Thermally stimulated luminescence (TSL) glow curves of the γ-irradiated phosphor, along with trap parameters, dose-response, and the possible TSL mechanism were also investigated. Positron annihilation lifetime spectroscopy was carried out to probe defects present in undoped and Ce-doped SrBPO5 .


Subject(s)
Boron/chemistry , Cerium/chemistry , Luminescence , Phosphates/chemistry , Strontium/chemistry , Ultraviolet Rays , Luminescent Measurements , Models, Molecular , Optical Phenomena , Particle Size , Temperature
7.
Nanotechnology ; 29(34): 345204, 2018 Aug 24.
Article in English | MEDLINE | ID: mdl-29856728

ABSTRACT

Ion beam irradiation technique has been proposed, for efficient, fast and eco-friendly reduction of graphene oxide (GO), as an alternative to the conventional methods. 5 MeV, Au+ ion beam has been used to reduce the free standing GO flake. Both electronic and nuclear energy loss mechanisms of the irradiation process play a major role in removal of oxygen moieties and recovery of graphene network. Atomic resolution scanning tunnelling microscopy analysis of the irradiated GO flake shows the characteristic honeycomb structure of graphene. X-ray absorption near edge structure analysis at C K-edge reveals that the features of the irradiated GO flake resemble the few layer graphene. Resonant Rutherford backscattering spectrometry analysis evidenced an enhanced C/O ratio of ∼23 in the irradiated GO. In situ sheet resistance measurements exhibit a sharp decrease of resistance (few 100 s of Ω) at a fluence of 6.5 × 1014 ions cm-2. Photoluminescence spectroscopic analysis of irradiated GO shows a sharp blue emission, while pristine GO exhibits a broad emission in the visible-near IR region. Region selective reduction, tunable electrical and optical properties by controlling C/O ratio makes ion irradiation as a versatile tool for the green reduction of GO for diverse applications.

8.
J Healthc Eng ; 2018: 9213707, 2018.
Article in English | MEDLINE | ID: mdl-29808111

ABSTRACT

This paper presents a classification system to classify the cognitive load corresponding to targets and distractors present in opposite visual hemifields. The approach includes the study of EEG (electroencephalogram) signal features acquired in a spatial attention task. The process comprises of EEG feature selection based on the feature distribution, followed by the stepwise discriminant analysis- (SDA-) based channel selection. Repeated measure analysis of variance (rANOVA) is applied to test the statistical significance of the selected features. Classifiers are developed and compared using the selected features to classify the target and distractor present in visual hemifields. The results provide a maximum classification accuracy of 87.2% and 86.1% and an average classification accuracy of 76.5 ± 4% and 76.2 ± 5.3% over the thirteen subjects corresponding to the two task conditions. These correlates present a step towards building a feature-based neurofeedback system for visual attention.


Subject(s)
Attention , Electroencephalography , Neurofeedback , Rehabilitation/methods , Visual Fields , Adult , Algorithms , Analysis of Variance , Brain-Computer Interfaces , Discriminant Analysis , Electrodes , Female , Humans , Male , Neural Networks, Computer , Neuroimaging , ROC Curve , Reproducibility of Results , Signal Processing, Computer-Assisted , Support Vector Machine , Young Adult
9.
Nanotechnology ; 29(18): 185701, 2018 May 04.
Article in English | MEDLINE | ID: mdl-29451500

ABSTRACT

The tunable electronic, electrical and optical properties of graphene oxide (GO) sheets were investigated using a controlled reduction by 500 keV Ar+-ion irradiation. The carbon to oxygen ratio of the GO sheets upon the ion beam reduction has been estimated using resonant Rutherford backscattering spectrometry analyses and its effect on the electrical and optical properties of GO sheets has been studied using sheet resistance measurements and photoluminescence (PL) measurements. The restoration of sp 2-hybridized carbon atoms within the sp 3 matrix is found to be increases with increasing the Ar+-ion fluences as evident from Fourier transform infrared, and x-ray absorption near-edge structure measurements. The decrease in the number of disorder-induced local density of states (LDOSs) within the π-π* gap upon the reduction causes the shifting of PL emission from near infra-red to blue region and decreases the sheet resistance. The improved electrical and optical properties of GO sheets were correlated to the decrease in the number of LDOSs within the π-π* gap. Our experimental investigations suggest ion beam irradiation is one of an effective approaches to reduce GO to RGO and to tailor its electronic, electrical and optical properties.

10.
J Med Eng Technol ; 42(2): 113-120, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29448856

ABSTRACT

Selective visual attention is the ability to selectively pay attention to the targets while inhibiting the distractors. This paper aims to study the targets and non-targets interplay in spatial attention task while subject attends to the target object present in one visual hemifield and ignores the distractor present in another visual hemifield. This paper performs the averaged evoked response potential (ERP) analysis and time-frequency analysis. ERP analysis agrees to the left hemisphere superiority over late potentials for the targets present in right visual hemifield. Time-frequency analysis performed suggests two parameters i.e. event-related spectral perturbation (ERSP) and inter-trial coherence (ITC). These parameters show the same properties for the target present in either of the visual hemifields but show the difference while comparing the activity corresponding to the targets and non-targets. In this way, this study helps to visualise the difference between targets present in the left and right visual hemifields and, also the targets and non-targets present in the left and right visual hemifields. These results could be utilised to monitor subjects' performance in brain-computer interface (BCI) and neurorehabilitation.


Subject(s)
Evoked Potentials/physiology , Female , Humans , Male , Neurological Rehabilitation , Reaction Time/physiology , Visual Perception/physiology
11.
Phys Chem Chem Phys ; 19(20): 13316-13323, 2017 May 24.
Article in English | MEDLINE | ID: mdl-28492651

ABSTRACT

The influence of carbon concentration on the electronic and magnetic properties of C-implanted ZnO thin films has been studied using synchrotron radiation based X-ray absorption spectroscopic techniques and vibrating sample magnetometer measurements. 20 keV carbon ions were implanted in ZnO films with different fluences (2 × 1016, 4 × 1016 and 6 × 1016 ions per cm2). The pristine ZnO film shows diamagnetic behaviour while the C-implanted films exhibit room temperature ferromagnetism. Our first-principles calculations based on density functional theory show an appreciable magnetic moment only when the implanted C atom sits either in the O-site (2 µB) or in the interstitial position (1.88 µB), whereas the C atom in the Zn substitutional position does not possess any magnetic moment. X-ray absorption near edge structure analysis at the O K-edge reveals that the charge transfer from O-2p to the C-defect site causes the ferromagnetism in the C-implanted ZnO film at low fluence. However at high fluence, the implanted C replaces the lattice and produces more Zn vacancies, as evidenced by extended X-ray absorption fine structure studies at the Zn K-edge, which favors the ferromagnetism. The persistence of the implanted carbon and ferromagnetism of the C-implanted ZnO film has also been studied by isothermal annealing at 500 °C and discussed in detail.

12.
Phys Chem Chem Phys ; 19(16): 10518-10526, 2017 Apr 19.
Article in English | MEDLINE | ID: mdl-28387418

ABSTRACT

We delineated the role of thermally excited ripples on the thermal expansion properties of 2D honeycomb materials (free-standing graphene, 2D h-BN, and ML-MoS2), by explicitly carrying out three-dimensional (3D) and two-dimensional (2D) molecular dynamics simulations. In 3D simulations, the in-plane lattice parameter (a-lattice) of graphene and 2D h-BN shows thermal contraction over a wide range of temperatures and exhibits a strong system size dependence. The 2D simulations of the very same system show a reverse trend, where the a-lattice expands in the whole computed temperature range. In contrast to graphene and 2D h-BN, the a-lattice of ML-MoS2 shows thermal expansion in both 2D and 3D simulations and their system size dependence is marginal. By analyzing the phonon dispersion at 300 K, we found that the discrepancy between 2D and 3D simulations of graphene and 2D h-BN is due to the absence of out-of-plane bending modes (ZA) in 2D simulations, which is responsible for the thermal contraction of the a-lattice at low temperature. Meanwhile, all the phonon modes are present in the 2D phonon dispersion of ML-MoS2, which indicates that the origin of the ZA mode is not purely due to the out-of-plane movement of atoms and also its effect on thermal expansion is not significant as found in graphene and 2D h-BN.

13.
Vet World ; 9(8): 832-6, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27651670

ABSTRACT

AIM: The present study was conducted to evaluate the performance of gray, brown, and white varieties of Japanese quail (Coturnix coturnix japonica) with respect to body weight, egg production, and egg quality traits in the coastal climatic condition of Odisha. MATERIALS AND METHODS: A total of 500-day-old straight run Japanese quail chicks of three varieties, viz., gray, brown, and white were randomly selected and reared in deep litter system at Central Poultry Development Organization, Eastern Region, Bhubaneswar. The weekly body weight of the birds was recorded till their egg production stage (up to 6 weeks of age). The average egg production was recorded every biweekly from 6(th) to 20(th) week. Exterior and interior quality of eggs from each variety was determined at 6 weeks of age. RESULTS: The initial average weekly body weight of three varieties did not differ (p>0.05) among the varieties. However, from 1(st) to 6(th) week significantly higher body weight was observed in gray than white and brown. Brown varieties had reached 50% egg production 1 week earlier than gray and white. Brown had higher peak hen day (HD) production or hen-housed egg production followed by white and gray. External quality such as: Egg weight, egg length, egg width, volume, shape index, shell weight, shell thickness depicted no significant difference among the varieties except circumference length and circumference width, which were significantly higher (p≤0.05) in gray varieties than brown varieties. Internal egg characteristics such as: Albumen length, albumen width, albumen height, albumen index, yolk length, yolk width, yolk height, yolk index, albumen weight, yolk weight, Haugh unit revealed no significance difference among the varieties. CONCLUSION: It may be summarized from the findings that gray excelled in body weight followed by white and brown. Egg production potential in terms of hen house egg production or HD egg production was higher for brown followed by white and gray in the coastal climatic condition of Odisha.

14.
Phys Chem Chem Phys ; 18(4): 2672-81, 2016 Jan 28.
Article in English | MEDLINE | ID: mdl-26705543

ABSTRACT

The temperature dependent structural stability, frequency shift and linewidth of 2D hexagonal boron nitride (h-BN) are studied using a combination of lattice dynamics (LD) and molecular dynamics (MD) simulations. The in-plane lattice parameter shows a negative thermal expansion in the whole computed temperature range (0-2000 K). When the in-plane lattice parameter falls below the equilibrium value, the quasi-harmonic bending (ZA) mode frequency becomes imaginary along the Γ-M direction in the Brillouin zone, leading to a structural instability of the 2D sheet. The ZA mode is seen to be stabilized in the dispersion obtained from MD simulations, due to the automatic incorporation of higher order phonon scattering processes in MD, which are absent in a quasi-harmonic dispersion. The mode resolved phonon spectra computed with a quasi-harmonic method predict a blueshift of the longitudinal and transverse (LO/TO) optic mode frequencies with an increase in temperature. On the other hand, both canonical (NVT) and isobaric-isothermal (NPT) ensembles predict a redshift with an increase in temperature, which is more prominent in the NVT ensemble. The strong phonon-phonon coupling dominates over the thermal contraction effect and leads to a redshift in LO/TO mode frequency in the NPT ensemble simulations. The out-of-plane (ZO) optic mode quasi-harmonic frequencies are redshifted due to a membrane effect. The phonon-phonon coupling effects in the NVT and NPT ensemble simulations lead to a further reduction in the ZO mode frequencies. The linewidth of the LO/TO and ZO mode frequencies increases in a monotonic fashion. The temperature dependence of acoustic modes is also analyzed. The quasi-harmonic calculations predict a redshift of ZA mode, and at the same time the TA (transverse acoustic) and LA (longitudinal acoustic) mode frequencies are blueshifted. The strong phonon-phonon coupling in MD simulations causes a redshift of the LA and TA mode frequencies, while the ZA mode frequencies are blueshifted with an increase in temperature.

15.
Ultramicroscopy ; 159 Pt 2: 360-7, 2015 Dec.
Article in English | MEDLINE | ID: mdl-25754233

ABSTRACT

Oxide dispersion strengthened ferritic steels (ODS) are being considered for structural components of future designs of fission and fusion reactors because of their impressive high-temperature mechanical properties and resistance to radiation damage, both of which arise from the nanoscale oxide particles they contain. Because of the critical importance of these nanoscale phases, significant research activity has been dedicated to analysing their precise size, shape and composition (Odette et al., Annu. Rev. Mater. Res. 38 (2008) 471-503 [1]; Miller et al., Mater. Sci. Technol. 29(10) (2013) 1174-1178 [2]). As part of a project to develop new fuel cladding alloys in India, model ODS alloys have been produced with the compositions, Fe-0.3Y2O3, Fe-0.2Ti-0.3Y2O3 and Fe-14Cr-0.2Ti-0.3Y2O3. The oxide particles in these three model alloys have been studied by APT in their as-received state and following ion irradiation (as a proxy for neutron irradiation) at various temperatures. In order to adequately quantify the composition of the oxide clusters, several difficulties must be managed, including issues relating to the chemical identification (ranging and variable peak-overlaps); trajectory aberrations and chemical structure; and particle sizing. This paper presents how these issues can be addressed by the application of bespoke data analysis tools and correlative microscopy. A discussion follows concerning the achievable precision in these measurements, with reference to the fundamental limiting factors.

16.
Radiat Prot Dosimetry ; 163(4): 430-8, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25013033

ABSTRACT

Tb(3+)-doped SrSiO(3) phosphor synthesised by co-precipitation technique exhibits intense green emission due to cross-relaxation phenomena between Tb(3+) ions. Dosimetric properties of this phosphor have been investigated using thermoluminescence (TL) technique. A dosimetrically useful glow peak observed was at 581 K along with a linear dose response over the wide dose range (100 mGy-4 Gy). TL parameters such as trap depth (E), frequency factor (s) and the order of kinetics (b) are determined by different methods such as Chen's peak shape, initial rise, isothermal decay and variable heating rate methods. Results of these methods are compared and reported in this study.


Subject(s)
Luminescent Measurements , Silicates/radiation effects , Strontium/radiation effects , Terbium/chemistry , Thermoluminescent Dosimetry/methods , Kinetics , Radiation Dosage , Silicates/chemistry , Strontium/chemistry
17.
J Vector Borne Dis ; 50(4): 248-57, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24499846

ABSTRACT

BACKGROUND & OBJECTIVES: A new irrigation canal system is under construction in Dhenkanal district of Odisha, to increase the production of rice crop and thereby improve the living standard of farmers in the project area. Construction of canal may increase the transmission of malaria by creating vector breeding habitats. Knowledge about bionomics of vectors will support authorities for appropriate management of the disease in a changing ecological set up. The aim of this study was to assess the malaria transmission in the bank of the canal area under construction. METHODS: The entomological survey was carried out in three seasons, winter, summer and rainy during the period November 2008-October 2010 in the study area. Adult mosquitoes were collected by using suction tubes and flash lights. Mosquito species identification was done by using standard keys, separated according to abdominal conditions and were kept in an isopropanol for further molecular analysis of sibling species, presence of sporozoites and human blood meal. Larvae were collected by dippers and reared in the laboratory, and the emerged adults were identified to species. The epidemiology of malaria was evaluated from the data collected by the State Health Department. Insecticide succeptibility test was done by WHO method. RESULTS: The adult mosquito collection from the study area showed the prevalence of 14 species belonging to three genera, i.e. Anopheles, Culex and Aedes. The per man hour densities (PMHD) of An. culicifacies were 3.8, 1.4, 4.8; that of An. annularis were 2.1, 1, 2.1; and that of An. fluviatilis were 1.4, 0.3, 0.6 during winter, summer and rainy seasons respectively. Sibling species identified were: An. culicifacies A, B, C and D, An. annularis A and An. fluviatilis S. Sporozoite rates of An. culicifacies A and C were 1.1 and 0.5% respectively and that of An. annularis A was 2% (reported for the first time in the state). Both the vectors (An. culicifacies and An. annularis) showed resistance to DDT and malathion and were susceptible to deltamethrin, whereas An. fluviatilis was susceptible to all the three insecticides tested. INTERPRETATION & CONCLUSION: Anopheles culicifacies, An. fluviatilis and An. annularis were prevalent in all the three seasons. The artificial ponds and seepage pools of canal are the major breeding sites for An. culicifacies and An. annularis. Thus, in the canal command area, control of malaria transmission requires use of insecticide-treated bednets and use of biolarvicides (seepage pools) and larvivorous fish (artificial ponds) wherever feasible.


Subject(s)
Culicidae/parasitology , Endemic Diseases , Insect Vectors/parasitology , Insecticides/pharmacology , Malaria/transmission , Plasmodium/isolation & purification , Agricultural Irrigation , Animals , Climate , Culicidae/classification , Culicidae/physiology , DDT/pharmacology , Ecology , Female , Humans , Incidence , India/epidemiology , Insect Vectors/classification , Insect Vectors/physiology , Insecticide-Treated Bednets , Larva , Malaria/epidemiology , Malaria/parasitology , Malathion/pharmacology , Nitriles/pharmacology , Pyrethrins/pharmacology , Seasons , Sporozoites
18.
Trop Biomed ; 29(2): 277-85, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22735850

ABSTRACT

A focal outbreak of malaria at Sialimal sub-centre of Balasore district of Orissa was reported during the month of March, 2010. Three villages of the above block were affected. Regional Medical Research Centre, Bhubaneswar has conducted an entomological survey and a central clinic simultaneously, with door to door household survey to identify the fever cases. Within a span of 18 days around 172 fever cases were reported with Slide Positivity Rate (SPR) of 24.4% and Pf % of 81%. The malaria epidemiological data of the sub-centre area for last three years indicates that the area is non endemic for malaria (API was 0.81). Entomological survey revealed the presence of three known vectors of malaria i.e. Anopheles culicifacies, Anopheles annularis and Anopheles subpictus (local vector). Per Man Hour Density (PMHD) of these three species were 4.2, 2.8 and 10.8 respectively. Plasmodium falciparum sporozoites were detected in two An. culicifacies, in one An. annularis and in one An. subpictus. Larval density of Anopheline mosquitoes per dip ranged between 12 to 20. The vectors were found to be resistant to DDT but susceptible to synthetic pyrethroid. With this finding necessary remedial measures were taken by the government to curtail the transmission.


Subject(s)
Disease Outbreaks , Insect Vectors/parasitology , Malaria/epidemiology , Plasmodium falciparum/isolation & purification , Adolescent , Adult , Animals , Anopheles/classification , Anopheles/drug effects , Anopheles/parasitology , Child , Child, Preschool , DDT/pharmacology , Female , Health Knowledge, Attitudes, Practice , Humans , India/epidemiology , Insect Vectors/drug effects , Insecticide Resistance , Malaria/parasitology , Male , Plasmodium falciparum/pathogenicity , Seasons , Social Class , Young Adult
19.
Int J Obstet Anesth ; 21(2): 140-5, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22398360

ABSTRACT

BACKGROUND: Spinal anesthesia is a standard technique for cesarean section but can cause hypotension which may be related to venous pooling secondary to progesterone-induced decreases in vascular tone. This study investigated the use of a sequential compression mechanical pump with thigh-high sleeves with compression cycles timed to venous refilling. We hypothesized that this would recruit pooled venous blood from the lower limbs, maintain the central blood volume and thus decrease the incidence of hypotension. METHODS: One hundred parturients scheduled for elective cesarean section under spinal anesthesia were recruited and randomly assigned to use of either a mechanical pump (Group M) or control (Group C). A standardized protocol for co-hydration and anesthesia was followed. Hypotension, defined as a decrease in systolic blood pressure by >20% from baseline, was treated with 6-mg boluses of intravenous ephedrine. The incidence of hypotension was defined as the primary outcome. Median ephedrine requirement was taken as a measure of the severity of hypotension. RESULTS: Hypotension occurred in 12 of 47 (25.5%) patients in Group M compared to 27 of 45 (60%) in Group C (P=0.001). The median [range] ephedrine dose was greater in Group C (12 [0-24]mg) compared to Group M (0 [0-12]mg) (P<0.001). There was no difference between groups in the time to onset of hypotension. CONCLUSION: The use of a sequential compression mechanical pump that detects venous refilling and cycles accordingly, reduced the incidence and severity of hypotension after spinal anesthesia for cesarean section.


Subject(s)
Anesthesia, Obstetrical/adverse effects , Anesthesia, Spinal/adverse effects , Cesarean Section , Hypotension/prevention & control , Intermittent Pneumatic Compression Devices , Intraoperative Complications/prevention & control , Analysis of Variance , Elective Surgical Procedures , Equipment Design , Female , Humans , Hypotension/etiology , Intraoperative Complications/etiology , Pregnancy , Treatment Outcome
20.
Trop Biomed ; 28(1): 76-84, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21602772

ABSTRACT

To assess the impact of irrigation canals on malaria transmission, a study was conducted in Dhenkanal district of Orissa, India. The district is situated in the central part of Orissa and hyperendemic area for malaria. A canal system is being constructed for irrigation in the district, which passes through Parjang and Analabereni Primary Health Centres (PHC), endemic for malaria. The water has been released only up to Parjang (Canal with water -CWW) area during the end of 2004 and construction work is still going on in Analabereni PHC (Canal under construction-CUC). Retrospective clinical data (2001-2008) collected from health services from two study sites showed average Slide Positivity Rate (SPR) before release of water (2001-2004) was 9.25% and 18.04% in CWW and CUC areas, respectively. After release of water (2005-2008) the SPR was 5.77% and 10.19%, in CWW and CUC areas, respectively. The average Annual Parasite Incidence (API) was 7.66 and 22.67 in CWW and CUC areas before the release of water and 5.32 and 12.28 after release of water, respectively. A point fever survey was conducted in 2009 which revealed the presence of Plasmodium falciparum (Pf) and P. vivax (Pv) in both study areas. The survey found SPR of 18.82% and 24.54%, and Pf percentages of 75% and 85%, in CWW and CUC areas, respectively. The present study revealed the presence of two malaria vectors, Anopheles culicifacies and Anopheles annularis in the area. Vector Per Man Hour Density was 2.38 in CWW and 2.69 in CUC for An. culicifacies and 1.46 and 1.54 for An. annularis respectively. The sporozoites rates were found to be 3.6 and 3.8 for CWW and CUC, respectively. The present study reveals that, the construction of canal system did not increase the malaria prevalence during post water release period - implying that the malaria control programme was effective although still more intensive situation specific vectors control programme need to be continued simultaneously so that malaria transmission can be curtailed.


Subject(s)
Agriculture/methods , Anopheles/parasitology , Endemic Diseases , Human Activities , Malaria, Falciparum/epidemiology , Malaria, Vivax/epidemiology , Animals , Humans , Incidence , India/epidemiology , Malaria, Falciparum/parasitology , Malaria, Falciparum/transmission , Malaria, Vivax/parasitology , Malaria, Vivax/transmission , Plasmodium falciparum/isolation & purification , Plasmodium vivax/isolation & purification
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