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1.
Adv Mater ; : e2312856, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38775656

RESUMEN

Antiferroelectric ceramics, via the electric-field-induced antiferroelectric (AFE)-ferroelectric (FE) phase transitions, show great promise for high-energy-density capacitors. Yet, currently, only 70-80% energy release is found during a charge-discharge cycle. Here, for PbZrO3-based oxides, geometric nonlinear theory of martensitic phase transitions is applied (first used to guide supercompatible shape-memory alloys) to predict the reversibility of the AFE-FE transition by using density-functional theory to assess AFE/FE interfacial lattice-mismatch strain that assures ultralow electric hysteresis and extended fatigue lifetime. A good correlation of mismatch strain with electric hysteresis, hence, with energy efficiency of AFE capacitors is observed. Guided by theory, high-throughput material search is conducted and AFE compositions with a near-perfect charge-discharge energy efficiency (98.2%), i.e., near-zero hysteresis are discovered. And the fatigue life of the capacitor reaches 79.5 million charge-discharge cycles, a factor of 80 enhancement over AFE ceramics with large electric hysteresis.

2.
J Invertebr Pathol ; 203: 108058, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38182102

RESUMEN

White spot disease, caused by white spot syndrome virus (WSSV), has historically been the most devastating disease in shrimp aquaculture industry across the world. The mode of virus transmission is the most crucial stage in the dynamics and management of virus infection. This study explored the mechanism of vertical transmission of WSSV in Indian white shrimp, Penaeus indicus, potential native species for domestication and genetic improvement, using quantitative real time PCR (q RT PCR), light and electron microscopy, and in situ hybridization. Wild brooders of P. indicus (n = 2576) were sampled along the South east coast of India, during 2016 to 2021. Of these âˆ¼ 58 % of the brooders were positive for WSSV, and almost 50 % of infected wild brooders were at the various stages of reproductive maturation. WSSV-PCR positive brooders (n = 200) were analysed for vertical WSSV transmission. The q RT PCR studies of reproductive tissues revealed that 61 % (n = 13) of spermatophore, 54 % (n = 28) of immature ovaries and 48 % (n = 27) of ripe ovaries were infected with WSSV. The lowest level of infection was recorded in females with ripe ovaries (6.84 × 101 ± 9.79 × 100 ng genomic DNA) followed by fertilized eggs (1.59 × 102 ± 3.69 × 101 ng genomic DNA), and larvae (nauplius and zoea). The histology of gravid females with high WSSV copies showed pyknotic and karyorrhectic germinal vesicle with degenerated cortical rods. Conversely, the gravid females with low WSSV copies showed fully developed ovary without characteristic signs of WSSV infection. Transmission electron microscopic studies clearly established the presence of WSSV particles in both ovaries and spermatophores. When subjected to in situ hybridization, WSSV-specific signals were observed in connective tissues of spermatophore, although gravid ovary and fertilized eggs were failed to produce WSSV specific signals. The present study provides the first molecular and histological evidence for trans-ovarian vertical transmission of WSSV. Development of disease-free base population being the cornerstone and first step in establishing the breeding program, the present findings could be a basis for development of such programs.


Asunto(s)
Penaeidae , Virus del Síndrome de la Mancha Blanca 1 , Femenino , Animales , Virus del Síndrome de la Mancha Blanca 1/genética , Prevalencia , Reacción en Cadena en Tiempo Real de la Polimerasa , ADN Viral/análisis , Acuicultura
3.
Mol Genet Genomics ; 297(2): 495-505, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35129686

RESUMEN

Gut microbiota is known to influence the physiology, health, nutrient absorption, reproduction, and other metabolic activities of aquatic organisms. Microbial composition can influence intestinal immunity and are considered as health indicators. Information on gut microbial composition provides potential application possibilities to improve shrimp health and production. In the absence of such information for Penaeus indicus, the present study reports the microbial community structure associated with its early developmental stages. Bacterial community associated with the early developmental stages (egg, nauplii, zoea, mysis, PL1, PL6 and PL12) from two hatchery cycles were analysed employing 16S rRNA high throughput sequencing. Proteobacteria and Bacteroidetes, were the two dominant phyla in P. indicus development stages. Sequential sampling revealed the constant change in the bacterial composition at genus level. Alteromonas was dominant in egg and nauplii stage, whilst Ascidiaceihabitans (formerly Roseobacter) was the dominant genera in both PL6 and PL12. The bacterial composition was highly dynamic in early stages and our study suggests that the mysis stage is the critical phase in transforming the microbial composition and it gets stabilised by early post larval stages. This is the first report on the composition of microbiota in early developmental stages of P. indicus. Based on these results the formation of microbial composition seems to be influenced by feeding at early stages. The study provides valuable information to device intervention strategies for healthy seed production.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Penaeidae , Animales , Bacterias/genética , Microbioma Gastrointestinal/genética , Microbiota/genética , Penaeidae/genética , ARN Ribosómico 16S/análisis , ARN Ribosómico 16S/genética
4.
Fish Shellfish Immunol ; 119: 31-41, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34487828

RESUMEN

The present study focuses on the immunity and growth of Penaeus indicus fed with varying protein levels (25%, 30%, and 35%) in a biofloc based rearing system. A 120 days growth trial was carried out using juvenile Penaeus indicus (0.71 ± 0.01) with dietary protein level, 25% (LP), 30% (MP), and 35% (HP), and a control diet-fed with 35% acted as control group resulting in 4 treatments each with four replicates and were randomly assigned 16 tank units (7500 L each). A combination of different carbon sources (molasses, wheat flour, and rice bran in 2:1:1 ratio), yeast and a probiotic (Bacillus sp.) consortium were used for the development of biofloc. At the end of the trial, the growth parameters of shrimps viz., initial weight, feed conversion ratio (FCR), and daily growth coefficient (DGC) were computed. The results indicated that shrimp fed with medium (30%) protein (MP) diet recorded significantly (P < 0.05) improved growth performance compared to high protein fed group (35%) and low protein (25%) fed group (LP) in a biofloc system and control group (35%). The immunological parameters such as hemagglutination activity (HA) assay, serum protein, lysozyme, phenol oxidase (PO), and inhibition of superoxide dismutase (SOD) activity were observed in serum, plasma, and hemocyte lysate supernatant (HLS). The HA activity, PO activity in plasma was found to be higher in high protein fed animals, whereas medium protein resulted in enhanced PO activity in serum. Similarly, lysozyme and SOD were inhibited well in high protein fed animals compared to the low protein fed group. The vital immune genes's mRNA profiling showed a potential rise in the expressional pattern in MP and HP treatments compared to LP and control. BGBP (beta-1,3-glucan binding protein) and hemocyanin mRNA transcript levels were highly upregulated in the HP (5 fold) and moderately expressed in MP (2 fold) and LP (1-2 fold). The transcripts of peroxinectin, antimicrobial peptides like crustin showed significant upregulation in HP followed by in MP and LP and control. Likewise, other immune genes, such as SOD, prophenoloxidase (proPO), showed a similar trend in a marginal way, indicating immunomodulation in the biofloc groups. This study suggested that biofloc with high protein (35%) supplementation can substantially enhance the immune response of shrimps, although medium protein level (30%) is optimum for improving the survival, growth, and in turn economic return in Indian white shrimp.


Asunto(s)
Penaeidae , Alimentación Animal/análisis , Animales , Péptidos Antimicrobianos , Acuicultura , Dieta/veterinaria , Suplementos Dietéticos , Harina , Inmunidad , Inmunidad Innata , Muramidasa , Penaeidae/genética , ARN Mensajero , Superóxido Dismutasa , Triticum
5.
Sci Rep ; 11(1): 15831, 2021 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-34349168

RESUMEN

Luminescent vibriosis is a major bacterial disease in shrimp hatcheries and causes up to 100% mortality in larval stages of penaeid shrimps. We investigated the virulence factors and genetic identity of 29 luminescent Vibrio isolates from Indian shrimp hatcheries and farms, which were earlier presumed as Vibrio harveyi. Haemolysin gene-based species-specific multiplex PCR and phylogenetic analysis of rpoD and toxR identified all the isolates as V. campbellii. The gene-specific PCR revealed the presence of virulence markers involved in quorum sensing (luxM, luxS, cqsA), motility (flaA, lafA), toxin (hly, chiA, serine protease, metalloprotease), and virulence regulators (toxR, luxR) in all the isolates. The deduced amino acid sequence analysis of virulence regulator ToxR suggested four variants, namely A123Q150 (AQ; 18.9%), P123Q150 (PQ; 54.1%), A123P150 (AP; 21.6%), and P123P150 (PP; 5.4% isolates) based on amino acid at 123rd (proline or alanine) and 150th (glutamine or proline) positions. A significantly higher level of the quorum-sensing signal, autoinducer-2 (AI-2, p = 2.2e-12), and significantly reduced protease activity (p = 1.6e-07) were recorded in AP variant, whereas an inverse trend was noticed in the Q150 variants AQ and PQ. The pathogenicity study in Penaeus (Litopenaeus) vannamei juveniles revealed that all the isolates of AQ were highly pathogenic with Cox proportional hazard ratio 15.1 to 32.4 compared to P150 variants; PP (5.4 to 6.3) or AP (7.3 to 14). The correlation matrix suggested that protease, a metalloprotease, was positively correlated with pathogenicity (p > 0.05) and negatively correlated (p < 0.05) with AI-2 and AI-1. The syntenic organization of toxS-toxR-htpG operon in V. campbellii was found to be similar to pathogenic V. cholerae suggesting a similar regulatory role. The present study emphasizes that V. campbellii is a predominant pathogen in Indian shrimp hatcheries, and ToxR plays a significant role as a virulence regulator in the quorum sensing-protease pathway. Further, the study suggests that the presence of glutamine at 150th position (Q150) in ToxR is crucial for the pathogenicity of V. campbellii.


Asunto(s)
Proteínas Bacterianas/metabolismo , Infecciones por Bacterias Gramnegativas/complicaciones , Luminiscencia , Penaeidae/microbiología , Percepción de Quorum , Vibrio/patogenicidad , Factores de Virulencia/metabolismo , Secuencia de Aminoácidos , Animales , Proteínas Bacterianas/genética , Infecciones por Bacterias Gramnegativas/microbiología , Homología de Secuencia , Vibrio/genética , Vibrio/aislamiento & purificación , Virulencia , Factores de Virulencia/genética
6.
Nutr Cancer ; 73(11-12): 2363-2375, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32972250

RESUMEN

OBJECTIVE: The present study aimed to evaluate the efficacy of methanolic extract of Muntingia calabura L. leaves (MEMC) in ameliorating oxidative stress and inflammation associated with 1,2-dimethyl hydrazine (DMH) induced colon cancer. METHODS: The antioxidant enzymes, oxidative stress markers, liver and renal toxicity markers were evaluated. Histopathological examination of colon tissues was carried out with the aid of alcian blue stain and Hematoxylin and Eosin stain. RESULTS: MEMC supplementation at doses of 100 and 200 mg/kg body weight of rats causes the antioxidant enzymic levels to retain near to its normal range. Meanwhile the oxidative stress markers, which showed an elevation from its normal level upon DMH administration, gets significantly reduced on MEMC treatment. Histopathological observation also revealed that the severity of colorectal cancer was reduced by the supplementation of MEMC. CONCLUSION: The findings from the present study showed that MEMC can exert a potential role to ameliorate the oxidative stress and inflammation associated with colorectal cancer.


Asunto(s)
Neoplasias del Colon , Metanol , 1,2-Dimetilhidrazina/toxicidad , Animales , Antioxidantes/farmacología , Carcinogénesis , Colon , Neoplasias del Colon/inducido químicamente , Neoplasias del Colon/tratamiento farmacológico , Metanol/uso terapéutico , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Ratas , Ratas Wistar
7.
Eur Arch Paediatr Dent ; 21(1): 61-66, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31111439

RESUMEN

PURPOSE: To evaluate the effect of two herbal mouthwashes containing aloe vera and tea tree oil, on the oral health of school children. METHODS: A double-blinded, placebo-controlled prospective interventional study was conducted in school children aged 8-14 years. The study participants were divided into four groups depending upon the mouthwash used: Group 1 (aloe vera), Group 2 (chlorhexidine), Group 3 (tea tree oil) and Group 4 (placebo). The variables studied included plaque index, gingival index and salivary Streptococcus mutans counts, which were recorded at baseline, 4 weeks after supervised mouth rinse and after 2 weeks of stopping the mouth rinse. RESULTS: A total of 89 boys and 63 girls were included. A statistically significant decrease in all variables was noted after the use of both the herbal preparations at the end of 4 weeks which was maintained after the 2-week washout period (p < 0.001). The difference in variables between groups using aloe vera, Tea tree oil and chlorhexidine, was not statistically significant. CONCLUSION: The use of aloe vera and tea tree oil mouthwashes can decrease plaque, gingivitis and S. mutans in the oral cavity in children. The activity of these two agents is comparable to that of chlorhexidine.


Asunto(s)
Aloe , Gingivitis , Antisépticos Bucales , Salud Bucal , Aceite de Árbol de Té , Adolescente , Niño , Clorhexidina , Placa Dental/prevención & control , Femenino , Gingivitis/prevención & control , Humanos , Masculino , Estudios Prospectivos , Aceite de Árbol de Té/uso terapéutico
8.
Sci Rep ; 9(1): 19306, 2019 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-31848425

RESUMEN

Nutritional composition of hilsa, Tenualosa ilisha, of different size groups was analyzed to study variations in their composition with the progression of growth, and to correlate it with the flavor of adult hilsa (>800 g size) collected from different riverine systems (Hooghly and Padma). The amino acid analysis revealed significantly higher arginine (P < 0.01), methionine (P < 0.01) and glycine (P < 0.05) contents in samples below 5 g, whereas samples above 800 g had higher (P < 0.01) leucine and isoleucine contents. Total saturated and monounsaturated fatty acids were lower (P < 0.01) in fish below 5 g as compared to larger size groups (>5 g), whereas docosahexaenoic acid was higher (P < 0.01) in fish below 5 g size. Nutritional composition of adult hilsa (>800 g) from Hooghly and Padma river revealed higher (P < 0.01) aspartic acid, glutamic acid, alanine, palmitoleic and oleic acid in samples from the Padma, whereas leucine and isoleucine contents were higher (P < 0.01) in hilsa from Hooghly. Sensory evaluation test revealed superior (P < 0.05) taste, aroma, and muscle texture of hilsa from the Padma as compared to those from Hooghly. Higher alanine, aspartic acid, glutamic acid, oleic acid, and palmitoleic acid along with higher n3:n6 fatty acid are attributed to the superior taste of hilsa from the Padma.


Asunto(s)
Peces , Músculos , Valor Nutritivo , Gusto , Aminoácidos/química , Animales , Humanos , Ríos
9.
ACS Appl Mater Interfaces ; 10(10): 8739-8748, 2018 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-29446613

RESUMEN

Efficiency of hydrogen evolution via water electrolysis is mainly impeded by the kinetically sluggish oxygen evolution reaction (OER). Thus, it is of great significance to develop highly active and stable OER catalyst for alkaline water electrolysis or to substitute the more kinetically demanding acidic OER with a facile electron-donating reaction such that OER is no longer the bottleneck half-reaction for either acidic or alkaline water electrolysis. Herein, the hierarchical Fe-Ni phosphide shelled with ultrathin carbon networks on Ni foam (FeNiP@C) is reported and shows exceptional OER activity and enhanced chemical stability in 1 M KOH. This unique electrode provides large active sites, facile electron transport pathways, and rapid gas release, resulting in a remarkable OER activity that delivers a current density of 100 mA/cm2 at an overpotential of 182 mV with a Tafel slope of 56 mV/dec. Combining the hydrogen evolution reaction with organic pollutant (methylene blue) oxidation, a multifunctional electrolyzer for simultaneous cost-effective hydrogen generation and organic pollutant decomposition in acid wastewater is proposed. Our strategies in this work provide attractive opportunities in energy- and environment-related fields.

10.
ACS Nano ; 11(6): 6389-6395, 2017 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-28557439

RESUMEN

The two-dimensional (2D) semiconductor molybdenum disulfide (MoS2) has attracted widespread attention for its extraordinary electrical-, optical-, spin-, and valley-related properties. Here, we report on spin-polarized tunneling through chemical vapor deposited multilayer MoS2 (∼7 nm) at room temperature in a vertically fabricated spin-valve device. A tunnel magnetoresistance (TMR) of 0.5-2% has been observed, corresponding to spin polarization of 5-10% in the measured temperature range of 300-75 K. First-principles calculations for ideal junctions result in a TMR up to 8% and a spin polarization of 26%. The detailed measurements at different temperature, bias voltages, and density functional theory calculations provide information about spin transport mechanisms in vertical multilayer MoS2 spin-valve devices. These findings form a platform for exploring spin functionalities in 2D semiconductors and understanding the basic phenomena that control their performance.

11.
Nano Lett ; 14(8): 4314-21, 2014 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-25073904

RESUMEN

MoS2 is an important member of the transition metal dichalcogenides that is emerging as a potential 2D atomically thin layered material for low power electronic and optoelectronic applications. However, for MoS2 a critical fundamental question of significant importance is how the surface energy and hence the wettability is altered at the nanoscale in particular, the role of crystallinity and orientation. This work reports on the synthesis of large area MoS2 thin films on insulating substrates (SiO2/Si and Al2O3) with different surface morphology via vapor phase deposition by varying the growth temperatures. The samples were examined using transmission electron microscopy and Raman spectroscopy. From contact angle measurements, it is possible to correlate the wettability with crystallinity at the nanoscale. The specific surface energy for few layers MoS2 is estimated to be about 46.5 mJ/m(2). Moreover a layer thickness-dependent wettability study suggests that the lower the thickness is, the higher the contact angle will be. Our results shed light on the MoS2-water interaction that is important for the development of devices based on MoS2 coated surfaces for microfluidic applications.

12.
J Periodontal Res ; 49(6): 719-28, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24329044

RESUMEN

BACKGROUND AND OBJECTIVE: Studies have shown that erythrocyte counts and hemoglobin levels are reduced in patients with chronic periodontitis, suggesting that this condition may be associated with anemia of chronic disease. Although increased leukocyte counts have been reported in aggressive periodontitis, very little is known about the effects of aggressive periodontitis on erythrocyte counts. The present study was undertaken to determine whether generalized aggressive periodontitis is associated with reduced erythrocyte counts and reduced hemoglobin levels. MATERIAL AND METHODS: The present study was conducted as a case-control study in which 64 patients with generalized aggressive periodontitis were categorized as cases and 58 periodontally healthy individuals were categorized as controls. Erythrocyte parameters (such as erythrocyte count, hemoglobin concentration, and hematocrit and erythrocyte indices) and clinical parameters (such as gingival index, plaque index, probing depth, clinical attachment level and percentage of severe sites) were recorded. RESULTS: Significant differences were observed between cases and controls in mean erythrocyte count (4.45 ± 0.6 × 10(6) erythrocytes/µL and 4.78 ± 0.56 × 10(6) erythrocytes/µL respectively, p = 0.002) and hemoglobin level (12.43 ± 1.83 g/dL and 13.53 ± 1.64 g/dL, respectively, p = 0.001). Other erythrocyte parameters, such as hematocrit, mean corpuscular volume and mean corpuscular hemoglobin, were also significantly lower among cases compared with controls. Logistic regression analyses showed that generalized aggressive periodontitis was significantly associated with lower erythrocyte counts ( p = 0.032) and a lower hemoglobin concentration ( p = 0.017). CONCLUSION: The findings of the present study suggest that patients with generalized aggressive periodontitis tend to have lower erythrocyte counts and lower hemoglobin levels compared with periodontally healthy controls. This suggests that generalized aggressive periodontitis, like chronic periodontitis, may be associated with a risk for anemia of chronic disease.


Asunto(s)
Periodontitis Agresiva/sangre , Recuento de Eritrocitos , Hemoglobinas/análisis , Adulto , Periodontitis Agresiva/clasificación , Consumo de Bebidas Alcohólicas , Estatura , Índice de Masa Corporal , Peso Corporal , Estudios de Casos y Controles , Índice de Placa Dental , Índices de Eritrocitos/fisiología , Eritrocitos/patología , Conducta Alimentaria , Femenino , Hematócrito , Humanos , Renta , Masculino , Higiene Bucal , Pérdida de la Inserción Periodontal/sangre , Pérdida de la Inserción Periodontal/clasificación , Índice Periodontal , Bolsa Periodontal/sangre , Bolsa Periodontal/clasificación , Clase Social , Uso de Tabaco , Cepillado Dental/instrumentación , Pastas de Dientes/uso terapéutico
13.
J Periodontal Res ; 48(5): 623-31, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23425304

RESUMEN

BACKGROUND AND OBJECTIVE: The effects of tobacco smoking on the prevalence and severity of periodontal disease have been well documented. However, very few studies have assessed the effects of oral smokeless tobacco (ST) on the periodontium. Considering the widespread use of ST products globally, the effects of such products on the periodontal tissues may be important. The present study was performed to compare retrospectively the patterns of periodontal destruction among oral ST users and never-users with periodontitis. MATERIAL AND METHODS: Data from 149 patients with periodontitis (60 ST users and 89 never-users) were compared for mean scores of probing depth, recession (REC) and clinical attachment loss (CAL) and the mean percentage of sites with different ranges of probing depth, REC and CAL. RESULTS: For full-mouth scores, mean REC and CAL were significantly higher in ST users than in never-users (p < 0.001 and p = 0.008, respectively). For different regions of the dentition, mean scores of REC were significantly higher among ST users than among never-users (p < 0.001 for all regions), and mean scores of CAL were significantly higher for ST users in mandibular (p < 0.001), buccal (p = 0.008), lingual (p = 0.022), anterior (p = 0.012) and molar (p = 0.009) sites. Generally, there were higher percentages of sites with shallow pockets (0-3 mm), REC of ≥ 1 mm and CAL of ≥ 3 mm in ST users than in never-users. However, only differences for REC categories were significant for all regions (p < 0.001). ST users had a significantly higher proportion of sites with CAL of ≥8 mm for full-mouth sites (p = 0.003), mandibular teeth (p < 0.001), buccal sites (p = 0.002), anterior teeth (p = 0.040) and molars (p = 0.007). CONCLUSION: ST users tend to have more severe REC and CAL and a greater proportion of sites with higher values of REC and CAL compared with never-users. The greatest increase in severity of CAL was found to be localized to sites on mandibular teeth, buccal surfaces, anteriors and molars, which may be a result of the retention of the ST product in the oral cavity.


Asunto(s)
Periodontitis/clasificación , Tabaco sin Humo , Adulto , Diente Canino/patología , Recesión Gingival/clasificación , Recesión Gingival/patología , Humanos , Incisivo/patología , Mandíbula/patología , Maxilar/patología , Diente Molar/patología , Pérdida de la Inserción Periodontal/clasificación , Pérdida de la Inserción Periodontal/patología , Bolsa Periodontal/clasificación , Bolsa Periodontal/patología , Periodontitis/patología , Estudios Retrospectivos
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