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1.
Sci Total Environ ; 785: 147319, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33957597

RESUMO

In the 21st century, groundwater depletion is posing a serious threat to humanity throughout the world, particularly in developing nations. India being the largest consumer of groundwater in the world, dwindling groundwater storage has emerged as a serious concern in recent years. Consequently, the judicious and efficient management of vital groundwater resources is one of the grand challenges in India. Groundwater modeling is a promising tool to develop sustainable management strategies for the efficient utilization of this treasured resource. This study demonstrates a pragmatic framework for predicting seasonal groundwater levels at a large scale using real-world data. Three relatively powerful Machine Learning (ML) techniques viz., ANFIS (Adaptive Neuro-Fuzzy Inference System), Deep Neural Network (DNN) and Support Vector Machine (SVM) were employed for predicting seasonal groundwater levels at the country scale using in situ groundwater-level and pertinent meteorological data of 1996-2016. ANFIS, DNN and SVM models were developed for 18 Agro-Ecological Zones (AEZs) of India and their efficacy was evaluated using suitable statistical and graphical indicators. The findings of this study revealed that the DNN model is the most proficient in predicting seasonal groundwater levels in most AEZs, followed by the ANFIS model. However, the prediction ability of the three models is 'moderate' to 'very poor' in 3 AEZs ['Western Plain and Kutch Peninsula' in Western India, and 'Deccan Plateau (Arid)' and 'Eastern Ghats and Deccan Plateau' in Southern India]. It is recommended that groundwater-monitoring network and data acquisition systems be strengthened in India in order to ensure efficient use of modeling techniques for the sustainable management of groundwater resources.

2.
Food Microbiol ; 91: 103538, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32539949

RESUMO

Surface contamination with droplets containing bacteria is of concern in the food industry and other environments where hygiene control is essential. Deposition patterns after the drying of contaminated droplets is affected by numerous parameters. The present study evaluated the rate of evaporation and the shape of deposition patterns after the drying of water droplets on a panel of materials with different surface properties (topography, hydrophobicity). The influence of the particle properties (in this study 1 µm-microspheres and two bacterial spores) was also investigated. Polystyrene microspheres were hydrophobic, while Bacillus spores were hydrophilic or hydrophobic, and surrounded by different surface features. In contrast to material topography, hydrophobicity was shown to deeply affect droplet evaporation, with the formation of small, thick deposits with microspheres or hydrophilic spores. Among the particle properties, the spore morphology (size and round/ovoid shape) did not clearly affect the deposition pattern. Conversely, hydrophobic spores aggregated to form clusters, which quickly settled on the materials and either failed to migrate, or only migrated to a slight extent on the surface, resulting in a steady distribution of spores or spore clusters over the whole contaminated area. Adherent bacteria or spores are known to be highly resistant to many stressful environmental conditions. In view of all the quite different patterns obtained following drying of spore-containing droplets, it seems likely that some of these would entail enhanced resistance to hygienic processes.


Assuntos
Dessecação , Manufaturas/análise , Água , Bacillus/química , Bacillus/classificação , Bacillus/fisiologia , Aderência Bacteriana , Interações Hidrofóbicas e Hidrofílicas , Microesferas , Esporos Bacterianos/química , Esporos Bacterianos/classificação , Esporos Bacterianos/fisiologia , Propriedades de Superfície , Água/análise , Microbiologia da Água
3.
Food Chem ; 309: 125594, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31683150

RESUMO

This study considered the effect of low energy microwave assisted freezing (MAF) on freezing time and quality attributes (microstructure, texture, drip loss and colour) of apple and potato. MAF of apples and potatoes was performed by applying constant microwave (MW) power (167 W/kg) and pulsed MW power (500 and 667 W/kg with 10 s pulse width and 20 s pulse interval resulting in an average power of 167 and 222 W/kg) during the freezing process. The temperature profile was monitored during the freezing process, and the microstructure was examined using X-ray micro-tomography and cryo-SEM. Other quality parameters such as texture, drip loss and colour were evaluated with thawed samples. It appeared that the freezing time was not affected by the MAF process. It is the first time that a MAF process is used for freezing plant-based products and showed that the application of microwaves during freezing process caused less freeze damage than the control condition.


Assuntos
Manipulação de Alimentos/métodos , Malus , Micro-Ondas , Solanum tuberosum , Microscopia Crioeletrônica , Qualidade dos Alimentos , Congelamento , Solanum tuberosum/química , Temperatura , Microtomografia por Raio-X
4.
Food Res Int ; 121: 479-496, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31108772

RESUMO

Freezing is an efficient and widely used method of food preservation. However, it can also cause irreversible damages at cellular level which in turn degrade the overall quality of the frozen food products. Therefore, qualitative and quantitative methods and technologies that will be able to evaluate with accuracy the freeze damage are of great importance. This review paper provides a comprehensive study of the methods that have been used to evaluate the freeze damage in fruits and vegetables. Further than the principles and the applications of those methods, the advantages and the limitations are also being discussed.


Assuntos
Manipulação de Alimentos , Congelamento , Frutas , Verduras , Parede Celular/química , Qualidade dos Alimentos , Tecnologia de Alimentos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Microscopia Confocal , Microscopia Eletrônica , Tomografia por Raios X
5.
PLoS One ; 13(12): e0209685, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30592745

RESUMO

Candidatus Neoehrlichia mikurensis (Ca. N. mikurensis; family Anaplasmataceae) is an emerging tick-borne pathogen that causes a systemic inflammatory syndrome with thrombotic complications. We report here the first identification of Ca. N. mikurensis in organ samples from small mammals captured in southwest South Korea. Nested PCR of groEL and 16S rRNA genes was used to confirm the identity of the bacteria present, and successfully amplified fragments were sequenced. All captured animals were identified as striped field mice (Apodemus agrarius), approximately 28.6% (4/14) and 21.4% (3/14) of which were found to be PCR-positive for Ca. N. mikurensis and Anaplasma phagocytophilum, respectively. The detection of Ca. N. mikurensis in these animals represents the first evidence of this pathogen in South Korea. Carriage of this bacterium by rodents highlights the need for more detailed investigation of their role in its transmission to humans.


Assuntos
Infecções por Anaplasmataceae/epidemiologia , Infecções por Anaplasmataceae/microbiologia , Anaplasmataceae/classificação , Anaplasmataceae/genética , Animais , Genes Bacterianos , Humanos , Camundongos , Filogenia , RNA Ribossômico 16S/genética , República da Coreia
6.
Am J Trop Med Hyg ; 97(2): 403-406, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28829732

RESUMO

Human granulocytic anaplasmosis (HGA) is a tick-borne infectious disease caused by Anaplasma phagocytophilum, an obligate intracellular bacterium. Until now, the utility of tick-bite site samples for HGA diagnosis has not been reported. Using a patient's buffy coat and tick-bite site crust samples, we performed polymerase chain reaction (PCR) testing using Ehrlichia- or Anaplasma-specific primers. PCR with buffy coat and crust samples obtained before doxycycline administration was positive. Six days after doxycycline administration, PCR with the buffy coat sample was negative but PCR with a crust tissue sample from the tick-bite site remained positive. This is the first case to suggest that crust tissue at the tick-bite site may be useful for early HGA diagnosis in patients who have already been treated with antibiotics such as doxycycline.


Assuntos
Anaplasmose/sangue , Anaplasmose/microbiologia , Picadas de Carrapatos/sangue , Picadas de Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/sangue , Doenças Transmitidas por Carrapatos/microbiologia , Idoso , Anaplasma phagocytophilum , Anaplasmose/diagnóstico , Diagnóstico Precoce , Humanos , Masculino , Reação em Cadeia da Polimerase , República da Coreia , Doenças Transmitidas por Carrapatos/diagnóstico , Resultado do Tratamento
7.
Luminescence ; 32(7): 1349-1353, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28503901

RESUMO

We report the thermoluminescence properties of Sr1.96 Al2 SiO7 :Eu0.04 and Sr1.92 Al2 SiO7 :Eu0.04 Dy0.04 phosphors. These phosphors were prepared by a high-temperature solid-state reaction method. The prepared phosphors were characterized by X-ray diffraction. A 254 nm source was used for ultraviolet (UV) irradiation and a 60 Co source was used for γ-irradiation. The effect of heating rate and UV-exposure were examined. The thermoluminescence temperature shifts to higher values with increasing heating rate and thermoluminescence intensity increases with increasing UV exposure time. The trapping parameters such as activation energy (E), order of kinetics and frequency factor (s) were calculated by peak shape method. The effect of γ- and UV-irradiation on thermoluminescence studies was also examined.


Assuntos
Disprósio/química , Európio/química , Substâncias Luminescentes/química , Raios gama , Cinética , Medições Luminescentes , Temperatura , Raios Ultravioleta , Difração de Raios X
8.
Luminescence ; 32(3): 375-381, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28394484

RESUMO

The present paper reports the thermoluminescence (TL) of (ZnS)1-x (MnTe)x nanophosphors that were prepared by a wet chemical synthesis method. The structure investigated by X-ray diffraction patterns confirms the formation of a sphalerite phase whose space group was found to be F 4¯3m. From XRD, TEM and SEM analyses the average sizes of the particles were found to be 12 nm, 11 nm and 15 nm, respectively. Initially the TL intensity increased with increasing values of x because the number of luminescence centres increased; however, for higher values of x the TL intensity decreased because of the concentration quenching. Thus the TL, mechanoluminescence and photoluminescence intensities are optimum for a particular value of x, that is for x = 0.05. Thermoluminescence of the (ZnS)1-x (MnTe)x nanophosphor has not been reported previously. There were two peaks seen in the thermoluminescence glow curves in which the first peak lay at 105-100 °C and the second peak lay at 183.5-178.5 °C. The activation energies for the first and second peaks were found to be 0.45 eV and 0.75 eV, respectively.


Assuntos
Luminescência , Nanopartículas/química , Sulfetos/química , Telúrio/química , Temperatura , Compostos de Zinco/química , Medições Luminescentes , Tamanho da Partícula , Propriedades de Superfície
9.
BMC Infect Dis ; 17(1): 72, 2017 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-28088169

RESUMO

BACKGROUND: Scedosporium apiospermum, which can usually be isolated from soil, polluted stream water and decaying vegetation, is increasingly recognized as an opportunistic dematiaceous fungus. The mortality rate of infection in immunocompromised hosts is over 50%. S. apiospermum is commonly responsible for dermal and epidermal infections (i.e., mycetoma) after traumatic penetration. CASE PRESENTATION: A 73-year-old woman was admitted to our hospital complaining of painful swelling and tenderness on the dorsum of the proximal left wrist and hand. The symptoms had persisted for approximately 2 months. A physical examination revealed a 4 x 3 cm, poorly defined, erythematous papule, which was fluctuant, with pustules and crusts on the dorsum of the left hand. CONCLUSIONS: We report a very rare case of tenosynovitis caused by S. apiospermum infection. We identified the infectious agent via molecular DNA sequencing. The infectious agent was initially misidentified as an Alternaria species by microscopic examination with lactophenol cotton blue (LPCB) staining. The infection was successfully treated with debridement and adjuvant fluconazole therapy.


Assuntos
DNA Fúngico/genética , Erros de Diagnóstico , Articulação da Mão , Micoses/diagnóstico , Scedosporium/genética , Tenossinovite/diagnóstico , Idoso , Alternaria , Alternariose/diagnóstico , Antifúngicos/uso terapêutico , Desbridamento , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/imunologia , Feminino , Fluconazol/uso terapêutico , Humanos , Hospedeiro Imunocomprometido , Imageamento por Ressonância Magnética , Micoses/complicações , Micoses/imunologia , Micoses/terapia , Análise de Sequência de DNA , Tenossinovite/complicações , Tenossinovite/imunologia , Tenossinovite/terapia
10.
Luminescence ; 32(1): 100-103, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27162108

RESUMO

Indirect focusing of the output from a pulsed infrared Nd3+ :YAG laser through a shock-generating layer onto organic crystals results in the emission of an intense microsecond duration pulse of mechanoluminescence (ML). The ML appears after a threshold laser fluence has been reached and increases sharply above this threshold. This specifies that there is a corresponding amplitude of a laser-induced shock wave that is necessary to induce crystal fracturing. Thus, the intensity of ML can be controlled by varying the laser fluence. Piezoelectric charges produced on the surfaces of a fractured crystal create the foundation for luminescence. Initially, the ML intensity increases with the shock wave pressure and time due to the creation of more surfaces in the crystal; the ML intensity reaches a peak value and then decreases over time. Thus, laser shock wave-induced ML provides a new optical technique for the study of materials under high pressure. Expressions explored for the characteristics of laser shock wave-induced ML satisfactorily explain the experimental results. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Lasers , Luminescência , Compostos Orgânicos/química , Cristalização
11.
Luminescence ; 32(2): 171-176, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27220804

RESUMO

The present paper reports the impulsive excitation of mechanoluminescence (ML) in Sr0.97 Al2 O4 :Eu0.01 ,Dy0.02 nanophosphors prepared using a combustion technique. The phosphors are characterized using X-ray powder diffraction (XRD), high-resolution transmission electron microscopy (HRTEM) and photoluminescence (PL). The XRD results show that the samples exhibit a monoclinic α-phase in the crystal structure. The space group of SrAl2 O4 :Eu,Dy nanophosphors is monoclinic P21 . The PL and ML spectra of SrAl2 O4 :Eu,Dy nanophosphors are excited using light with a wavelength of 365 nm and emission is found at 516 nm. The prepared nanophosphors exhibits an intense ML that can be seen in daylight with the naked eye. When a sample powder is deformed impulsively by the impact of a moving piston, the ML intensity initially increases linearly with time, attains a peak value, Im , at time tm , and then decreases with time. The peak ML intensity, Im , and total ML intensity, IT , increase linearly with applied pressure and impact velocity. The ML intensity decreases with successive impacts of load onto the phosphors, and the diminished ML intensity can be approximately recovered by UV irradiation. The activation energy using thermoluminescence is found to be 0.57 eV for SrAl2 O4 :Eu,Dy nanophosphors. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Alumínio/química , Disprósio/química , Európio/química , Luminescência , Oxigênio/química , Estrôncio/química , Microscopia Eletrônica de Transmissão , Nanoestruturas/química , Difração de Pó
12.
Springerplus ; 5(1): 1397, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27610316

RESUMO

Enterobacter aerogenes is recognized as an important bacterial pathogen in hospital-acquired infections. This report describes two unusual cases of septicemia caused by E. aerogenes in immunocompetent healthcare workers. E. aerogenes was isolated from blood cultures of the two patients experiencing septicemia. The clinical isolates were initially identified as E. aerogenes using a VITEK II automated system and 16S rRNA sequence analysis, and; both isolates involved in the outbreak shared a common pulse-field gel electrophoresis pattern. The similarities between the two cases included the simultaneous development of gastroenteritis symptoms, severe sepsis and thrombocytopenia after taking intravenous injections of ketorolac tromethamine. A common source of normal saline, a 100 mL bottle, was used for diluting the analgesic in both cases. In addition to the general population, healthcare workers, especially those who are also intravenous drug abusers, should be considered subjects that could cause a transmission of Enterobacter infection.

13.
Luminescence ; 31(8): 1422-1426, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27020788

RESUMO

Mechanoluminescence (ML) glow is produced on the back side when the front of a metal sample is irradiated with infrared Nd:YAG laser pulses. An incident laser beam with a power density below the plasma-flare onset threshold causes a rise in temperature in the studied metal. As the incident laser power density increases, the intensity of the ML glow signal also increases. On the basis of the laser power density-induced temperature, an expression is derived for the temperature-induced thermal stress. An expression is derived for the correlation between thermal stress and laser power density, which indicates that the temperature-induced thermal stress is directly related to the incident laser power density. In the region of plastic deformation, temperature-induced thermal stress is related to the strain and, consequently, to the emitted ML intensity. Finally, an expression is derived for the laser power dependence of the ML intensity, and good agreement is found between the theoretical and experimental results. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Lasers , Luminescência , Fenômenos Mecânicos , Metais/química
14.
Luminescence ; 31(7): 1302-1305, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26919481

RESUMO

This paper reports the luminescence behavior of Sr0.097 Al2 O4 :Eu0.01 ,Dy0.02 phosphors under UV-irradiation. The effect of UV-irradiation on afterglow (AG), thermoluminescence (TL) and mechanoluminescence (ML) of Sr0.097 Al2 O4 :Eu0.01 ,Dy0.02 phosphors is investigated. The space group of Sr0.097 Al2 O4 :Eu0.01 ,Dy0.02 phosphors is monoclinic P21 . The prepared phosphors exhibit a long AG, intense TL and ML. It is found that the AG, ML intensity and TL increase with increasing duration of irradiation time. The ML intensity decreases with successive impact of the load onto the phosphors, whereby the diminished ML intensity can be recovered by UV-irradiation. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Alumínio/química , Disprósio/química , Európio/química , Luminescência , Estrôncio/química , Raios Ultravioleta , Corantes Fluorescentes/química , Medições Luminescentes
15.
J Infect Chemother ; 22(2): 117-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26482919

RESUMO

The non-typhoidal bacterium Salmonella enterica subspecies enterica serovar Othmarschen (Salmonella Othmarschen) is a rare human pathogen. Abscess formation due to non-typhoidal Salmonella infections is a very rare complication in this antibiotic era. We report the first case of iliacus abscess after a short period of gastroenteritis which was caused by non-typhoidal Salmonella enterica belonging to group C1, serovar Othmarschen in a patient without any underlying conditions. A young female presented in our hospital complaining of pain in right hip joint area. She gave a history of watery diarrhea 3 days before the onset of pain. On examination the patient was ill-looking and there was tenderness in the right hip joint area. S. enterica was identified using 16S rRNA gene amplification by PCR and serotyped to be serovar Othmarschen from the pus sample of iliacus abscess. This is the first reported case of iliacus abscess due to Salmonella serover Othmarschen infection. Our case suggests that S. enterica serovar Othmarschen can cause severe focal infections associated with gastroenteritis. The literature on the rare association of Salmonella enterica and abscess formation is reviewed.


Assuntos
Abscesso/microbiologia , Infecções por Salmonella/diagnóstico , Infecções por Salmonella/microbiologia , Salmonella enterica/isolamento & purificação , Adulto , Feminino , Humanos , Adulto Jovem
16.
Luminescence ; 31(1): 67-75, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25991045

RESUMO

Mathematical approaches made for both the charged dislocation model and piezoelectrically induced electron bombardment model of fracto-mechanoluminescence (FML), the luminescence induced by fracture of solids, in ZnS:Mn phosphor indicate that the piezoelectrically induced electron bombardment model provides a dominating process for the FML of ZnS phosphors. The concentration of 3000 ppm Mn(2+) is optimal for ML intensity of ZnS:Mn phosphor. The decay time of ML gives the relaxation time of the piston used to deform the sample and the time tm of maximum of ML is controlled by both the relaxation time of the piston and decay time of charges on the newly created surfaces of crystals. As the product of the velocity of dislocations and pinning time of dislocations gives the mean free path of a moving dislocation. Both factors play an important role in the ML excitation of impurity doped II-VI semiconductors. The linear increase of total ML intensity IT with the impact velocity indicates that the damage increases linearly with impact velocity of the load. Thus, the ML measurement can be used remotely to monitor the real-time damage in the structures, and therefore, the ML of ZnS:Mn phosphor has also the potential for a structural health monitoring system.


Assuntos
Luminescência , Manganês/química , Sulfetos/química , Compostos de Zinco/química
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