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1.
World J Microbiol Biotechnol ; 37(4): 59, 2021 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-33660141

RESUMEN

Exploration of community structures, habitations, and potential plant growth promoting (PGP) attributes of endophytic bacteria through next generation sequencing (NGS) is a prerequisite to culturing PGP endophytic bacteria for their application in sustainable agriculture. The present study unravels the taxonomic abundance and diversity of endophytic bacteria inhabiting in vitro grown root, shoot and callus tissues of two aromatic rice cultivars through 16S rRNA gene-based Illumina NGS. Wide variability in the number of bacterial operational taxonomic units (OTUs) and genera was observed between the two samples of the root (55, 14 vs. 310, 76) and shoot (26, 12 vs. 276, 73) but not between the two callus samples (251, 61 vs. 259, 51), indicating tissue-specific and genotype-dependent bacterial community distribution in rice plant, even under similar gnotobiotic growth conditions. Sizes of core bacteriomes of the selected two rice genotypes varied from 1 to 15 genera, with Sphingomonas being the only genus detected in all six samples. Functional annotation, based upon the abundance of bacterial OTUs, revealed the presence of several PGP trait-related genes having variable relative abundance in tissue-specific and genotype-dependent manners. In silico study also documented a higher abundance of certain genes in the same biochemical pathway, such as nitrogen fixation, phosphate solubilization and indole acetic acid production; implying their crucial roles in the biosynthesis of metabolites leading to PGP. New insights on utilizing callus cultures for isolation of PGP endophytes aiming to improve rice crop productivity are presented, owing to constancy in bacterial OTUs and genera in callus tissues of both the rice genotypes.

2.
IEEE Trans Cybern ; PP2021 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-33705329

RESUMEN

Evolutionary multitasking, which solves multiple optimization tasks simultaneously, has gained increasing research attention in recent years. By utilizing the useful information from related tasks while solving the tasks concurrently, improved performance has been shown in various problems. Despite the success enjoyed by the existing evolutionary multitasking algorithms, still there is a lack of theoretical studies guaranteeing faster convergence compared to the conventional single task case. To analyze the effects of transferred information from related tasks, in this article, we first put forward a novel multitask gradient descent (MTGD) algorithm, which enhances the standard gradient descent updates with a multitask interaction term. The convergence of the resulting MTGD is derived. Furthermore, we present the first proof of faster convergence of MTGD relative to its single task counterpart. Utilizing MTGD, we formulate a gradient-free evolutionary multitasking algorithm called multitask evolution strategies (MTESs). Importantly, the single task evolution strategies (ESs) we utilize are shown to asymptotically approximate gradient descent and, hence, the faster convergence results derived for MTGD extend to the case of MTES as well. Numerical experiments comparing MTES with single task ES on synthetic benchmarks and practical optimization examples serve to substantiate our theoretical claim.

3.
Photochem Photobiol ; 2021 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-33694163

RESUMEN

A global challenge faced by light harvesting photocatalyst is how to promote the selective organic transformation, such as C-S bond formation via radical-radical coupling under solar light. Here, we report a two-dimensional covalent organic frameworks (2D-COFs), poly (perylene-imide-benzoquinone) nanorod through in situ condensation on flexible activated carbon cloth (PPIBNR-FACC) to function as a light harvester material for highly selective radical-radical coupling to vinyl sulfides (i.e. C-S bond activation). Such a structure supports charge transfer from PPIBNR to FACC, which is essential for the selective radical-radical coupling. Hence, organic transformation is attaining high yields and selectivity (~99%) under solar light using in situ prepared PPIBNR-FACC photocatalyst. The structural virtues of PPIBNR-FACC will trigger the utmost investigations into designable and versatile 2D-COFs for fine chemical synthesis.

4.
Artículo en Inglés | MEDLINE | ID: mdl-33783201

RESUMEN

We report an organic emitter containing a ß-triketone electron acceptor core and phenoxazine as the electron donors (TPXZBM) for solution-processed organic light-emitting diodes (OLEDs). The resulting molecule is very unusual because it shows both thermally activated delayed fluorescence and intramolecular proton transfer. We compare its performance with the previously reported diketone analogue PXZPDO. Solution-processed OLEDs of PXZPDO and TPXZBM show maximum external quantum efficiencies of 20.1 and 12.7%, respectively. The results obtained for the solution-processed PXZPDO-based device are as good as the previously reported evaporated device. At a very high luminance of 10,000 cd m-2, the efficiencies of the OLEDs were 10.6% for PXZPDO and 4.7% for TPXZBM, demonstrating a relatively low efficiency roll-off for TADF materials. The low efficiency roll-off was rationalized on the basis of the short delayed lifetimes of 1.35 µs for PXZPDO and 1.44 µs for TPXZBM. Our results suggest that intramolecular proton transfer may be useful for the design of OLED materials with a low efficiency roll-off.

5.
Artículo en Inglés | MEDLINE | ID: mdl-33666324

RESUMEN

We report the characterization of rotaxanes based on a carbazole-benzophenone thermally activated delayed fluorescence luminophore. We find that the mechanical bond leads to an improvement in key photophysical properties of the emitter, notably an increase in photoluminescence quantum yield and a decrease in the energy difference between singlet and triplet states, as well as fine tuning of the emission wavelength, a feat that is difficult to achieve when using covalently bound substituents. Computational simulations, supported by X-ray crystallography, suggest that this tuning of properties occurs due to weak interactions between the axle and the macrocycle that are enforced by the mechanical bond . This work highlights the benefits of using the mechanical bond to refine existing luminophores, providing a new avenue for emitter optimization that can ultimately increase the performance of these molecules.

6.
Environ Pollut ; 278: 116796, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33740601

RESUMEN

Grape pomace (GP) is a low-value by-product that contains a significant amount of high value-added products. The huge amount of non-edible residues of GP wastes (seeds, skins, leaves and, stems) produced by wine industries causes' environmental pollution, management issues as well as economic loss. Studies over the past 15-20 years revealed that GP could serve as a potential source for valuable bioactive compounds like antioxidants, bioactive, nutraceuticals, single-cell protein, and volatile organic compounds with an increasing scientific interest in their beneficial effects on human and animal health. However, the selection of appropriate techniques for the extraction of these compounds without compromising the stability of the extracted products is still a challenging task for the researcher. Based on the current scenario, the review mainly summarizes the novel applications of winery wastes in many sectors such as agriculture, pharmaceuticals, cosmetics, livestock fields, and also the bio-energy recovery system. We also summarize the existing information/knowledge on several green technologies for the recovery of value-added by-products. For the promotion of many emerging technologies, the entrepreneur should be aware of the opportunities/techniques for the development of high-quality value-added products. Thus, this review presents systematic information on value-added by-products that are used for societal benefits concerning the potential for human health and a sustainable environment.

7.
Br J Gen Pract ; 71(704): 109, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33632682
8.
BMJ Case Rep ; 14(2)2021 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-33541991

RESUMEN

Diabetes mellitus, type 1 in particular, is a well-recognised risk factor for melioidosis, a disease caused by Burkholderia pseudomallei Melioidosis is endemic in Southeast Asia and in northern Australia and has a variety of clinical presentation, isolated splenic abscess being one of them. B. pseudomallei, however, is an uncommon aetiology of splenic abscess. The diagnosis of melioidosis is often overlooked unless the clinician and the microbiologist are suspicious of the condition. Multiple splenic abscesses and perisplenic collection were noted in CT scan of the abdomen in a patient of type 1 diabetes, presenting with fever for preceding 4 weeks. B. pseudomallei was isolated from the splenic aspirate and the diagnosis was made based on gram stain and routine biochemical tests. He was successfully treated with antibiotics. We postulate that the likely route of infection was inoculation through skin, the integrity of which was compromised by multiple subcutaneous insulin injections.


Asunto(s)
Absceso Abdominal/complicaciones , Burkholderia pseudomallei/aislamiento & purificación , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Melioidosis , Enfermedades del Bazo/complicaciones , Dolor Abdominal/etiología , Adolescente , Diabetes Mellitus Tipo 1/complicaciones , Fiebre/etiología , Humanos , Masculino , Melioidosis/complicaciones , Melioidosis/diagnóstico , Tomografía Computarizada por Rayos X
9.
Curr Drug Saf ; 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33459244

RESUMEN

Xylometazoline, a sympathomimetic agent, is considered safe in hypertensive patients as a relief measure for nasal congestion with intranasal application. In the present case, a 58-year old male patient, having ischemic heart disease, controlled hypertension on telmisartan and bisoprolol, experienced hypertensive urgency in a span of two hours of intranasal administration of the paediatric formulation of xylometazoline. The interaction with bisoprolol should be kept in mind while using xylometazoline.

10.
IEEE Trans Cybern ; PP2021 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-33417576

RESUMEN

Adversarial attack can be deemed as a necessary prerequisite evaluation procedure before the deployment of any reinforcement learning (RL) policy. Most existing approaches for generating adversarial attacks are gradient based and are extensive, viz., perturbing every pixel of every frame. In contrast, recent advances show that gradient-free selective perturbations (i.e., attacking only selected pixels and frames) could be a more realistic adversary. However, these attacks treat every frame in isolation, ignoring the relationship between neighboring states of a Markov decision process; thus resulting in high computational complexity that tends to limit their real-world plausibility due to the tight time constraint in RL. Given the above, this article showcases the first study of how transferability across frames could be exploited for boosting the creation of minimal yet powerful attacks in image-based RL. To this end, we introduce three types of frame-correlation transfers (FCTs) (i.e., anterior case transfer, random projection-based transfer, and principal components-based transfer) with varying degrees of computational complexity in generating adversaries via a genetic algorithm. We empirically demonstrate the tradeoff between the complexity and potency of the transfer mechanism by exploring four fully trained state-of-the-art policies on six Atari games. Our FCTs dramatically speed up the attack generation compared to existing methods, often reducing the computation time required to nearly zero; thus, shedding light on the real threat of real-time attacks in RL.

11.
Arch Microbiol ; 2021 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-33388792

RESUMEN

Acid mine drainage (AMD) harbors all three life forms in spite of its toxic and hazardous nature. In comparison to bacterial diversity, an in-depth understanding of the archaeal diversity in AMD and their ecological significance remain less explored. Archaeal populations are known to play significant roles in various biogeochemical cycles within the AMD ecosystem, and it is imperative to have a deeper understanding of archaeal diversity and their functional potential in AMD system. The present study is aimed to understand the archaeal diversity of an AMD sediment of Malanjkhand Copper Project, India through archaea specific V6 region of 16S rRNA gene amplicon sequencing. Geochemical data confirmed the acidic, toxic, heavy metal-rich nature of the sample. Archaea specific V6-16S rRNA gene amplicon data showed a predominance of Thermoplasmata (BSLdp215, uncultured Thermoplasmata, and Thermoplasmataceae) and Nitrososphaeria (Nitrosotaleaceae) members constituting ~ 95% of the archaeal community. Uncultured members of Bathyarchaeia, Group 1.1c, Hydrothermarchaeota, and Methanomassiliicoccales along with Methanobacteriaceae, Methanocellaceae, Haloferaceae, Methanosaetaceae, and Methanoregulaceae constituted the part of rare taxa. Analysis of sequence reads indicated that apart from their close ecological relevance, members of the Thermoplasmata present in Malanjkhand AMD were mostly involved in chemoheterotrophy, Fe/S redox cycling, and with heavy metal resistance, while the Nitrososphaeria members were responsible for ammonia oxidation and fixation of HCO3- through 3-hydroxypropionate/4-hydroxybutyrate cycle at low pH and oligotrophic environment which subsequently played an important role in nitrification process in AMD sediment. Overall, the present study elucidated the biogeochemical significance of archaeal populations inhabiting the toxic AMD environment.

12.
Artículo en Inglés | MEDLINE | ID: mdl-33390015

RESUMEN

The removal of emerging environmental pollutants in water and wastewater is essential for high drinking water quality or for discharge to the environment. Electrochemical treatment is a promising technology shown to degrade undesirable organic compounds or metals via oxidation and reduction, and carbon-based electrodes have been reported. Here, we fabricated a robust, porous laser-induced graphene (LIG) electrode on a commercial water treatment membrane using the multilasing technique and demonstrated the electrochemical removal of iohexol, an iodine contrast compound, and chromium(VI), a highly toxic heavy metal ion. Multiple lasing resulted in a more ordered graphitic lattice, a more physically robust carbon layer, and a 3-4-fold higher electrical conductivity. These properties ultimately led to a more efficient electrochemical process, and the optimized LIG electrodes showed a higher hydrogen peroxide (H2O2) generation. At 3 V, 90% of Cr(VI) was removed after 6 h and reached >95% removal after 8 h at pH 2. Cr(VI) was mainly reduced to Cr(III), with small amounts of Cr(I) and Cr(0), which were partially deposited on the electrode membrane surface, confirmed with X-ray photoelectron spectroscopy and energy-dispersive X-ray spectroscopy analysis. Under the same conditions, 50% of iohexol was degraded after 6 h and the transformation products (TPs) were identified using ultra-performance liquid chromatography coupled with mass spectroscopy. A total of seven main intermediates were identified including deiodinated TPs (m/z = 695, 570, and 443), probably occurring via three transformation pathways including oxidative deiodination, amide hydrolysis, and deacetylation. The electrical energy costs calculated for the removal of 2 mg L-1 Cr(VI) was ∼$0.08/m3 in this system. Taken together, the porous LIG electrodes might be utilized for electrochemical removal of emerging contaminants in multiple applications because they can be rapidly formed on flexible polymer substrates at low cost.

13.
Indian Heart J ; 72(6): 614-618, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33357656

RESUMEN

Seventy-five patients with isolated severe MS (mitral valve area: 1.10 ± 0.15 cm2) and pulmonary hypertension underwent regional and global longitudinal strain (GLS) measurements of left (LV) and right ventricle (RV) at baseline and within 48 h after percutaneous balloon mitral valvuloplasty (PBMV). PBMV resulted in significant improvement in LV GLS (-16.35 ± 1.67% vs -19.98 ± 2.17%) and RV GLS (-10.34 ± 2.38% vs -13.83 ± 2.04%), p < 0.001 for both. Absolute increase in strain of basal segments of LV was more compared to mid and apical segments. We also found significant positive correlation between decrease in mean LA pressure (pre PBMV 28.91 ± 4.21 mm Hg vs post PBMV 10.55 ± 3.04 mm Hg, difference of 16.36 mm Hg; p < 0.001) obtained invasively during PBMV for 62 patients with improvement in LV GLS (r = 0.257, p = 0.048), RV GLS (r = 0.267, p = 0.043), and fall in right ventricular systolic pressure (r = 0.308, p = 0.022) that occurred post PBMV. The LV dysfunction is predominantly because of altered hemodynamics due to restricted LV filling with additional contribution from rheumatic involvement of basal LV myocardial segments. The improvement in LV deformation after PBMV is likely due to increase in preload. RV afterload reduction because of LA pressure decrease improved RV deformation.

14.
Elife ; 92020 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-33349332

RESUMEN

Given its glycemic efficacy and ability to reduce the body weight, glucagon-like peptide 1 receptor (GLP-1R) agonism has emerged as a preferred treatment for diabetes associated with obesity. We here report that a small-molecule Class 1 histone deacetylase (HDAC) inhibitor Entinostat (MS-275) enhances GLP-1R agonism to potentiate glucose-stimulated insulin secretion and decrease body weight in diet-induced obese (DIO) mice. MS-275 is not an agonist or allosteric activator of GLP-1R but enhances the sustained receptor-mediated signaling through the modulation of the expression of proteins involved in the signaling pathway. MS-275 and liraglutide combined therapy improved fasting glycemia upon short-term treatment and a chronic administration causes a reduction of obesity in DIO mice. Overall, our results emphasize the therapeutic potential of MS-275 as an adjunct to GLP-1R therapy in the treatment of diabetes and obesity.


Asunto(s)
Benzamidas/farmacología , Glucemia/efectos de los fármacos , Receptor del Péptido 1 Similar al Glucagón/agonistas , Inhibidores de Histona Desacetilasas/farmacología , Obesidad , Piridinas/farmacología , Animales , Masculino , Ratones , Ratones Endogámicos C57BL , Ratas , Ratas Sprague-Dawley
16.
Adv Mater ; 32(45): e2003911, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33029892

RESUMEN

Organic long-persistent luminescence (OLPL) is one of the most promising methods for long-lived-emission applications. However, present room-temperature OLPL emitters are mainly based on a bimolecular exciplex system which usually needs an expensive small molecule such as 2,8-bis(diphenyl-phosphoryl)dibenzo[b,d]thiophene (PPT) as the acceptor. In this study, a new thermally activated delayed fluorescence (TADF) compound, 3-(4-(9H-carbazol-9-yl)phenyl)acenaphtho[1,2-b]pyrazine-8,9-dicarbonitrile (CzPhAP), is designed, which also shows OLPL in many well-known hosts such as PPT, 2,2',2″-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H-benzimidazole) (TPBi), and poly(methyl methacrylate) (PMMA), without any exciplex formation, and its OLPL duration reaches more than 1 h at room temperature. Combining the low cost of PMMA manufacture and flexible designs of TADF molecules, pure organic, large-scale, color tunable, and low-cost room-temperature OLPL applications become possible. Moreover, it is found that the onset of the 77 K afterglow spectra from a TADF-emitter-doped film is not necessarily reliable for determining the lowest triplet state energy level. This is because in some TADF-emitter-doped films, optical excitation can generate charges (electron and holes) that can later recombine to form singlet excitons during the phosphorescence spectrum measurement. The spectrum taken in the phosphorescence time window at low temperature may consequently consist of both singlet and triplet emission.

17.
J Family Med Prim Care ; 9(8): 4074-4078, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33110812

RESUMEN

Background: Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disease characterized by the presence of persistent respiratory symptoms and airflow limitation due to airway and/or alveolar abnormalities owing to significant exposure to noxious particles or gases. Restricted activities of daily living as a result of reduced pulmonary function or dyspnea, impair quality of life in such patients. Methods: A cross-sectional study was conducted in a tertiary care hospital of Lucknow with 250 COPD patients to assess their health-related quality of life (HRQOL) using the St. Georges Respiratory Questionnaire (SGRQ). Study participants were selected using a systematic random sampling method. Results: HRQOL of participants was significantly impaired. Employment status and airflow limitation severity of study participants had a statistically significant negative correlation whereas, duration since diagnosis of disease was seen to have a statistically significant positive correlation with SGRQ scores. Conclusion: COPD deteriorated the quality of life of patients. The activity score was the most affected. Urban residents had a comparatively poor HRQOL.

18.
Indian J Tuberc ; 67(4): 495-501, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33077050

RESUMEN

BACKGROUND: The spectrum of morphological pattern in tubercular lymphandenopathies was observed to study the various cytomorphological patterns and their correlation with acid fast bacilli. METHODS: FNAC smears of 210 cases of granulomatous lymphadenitis stained with Giemsa, Pap and haematoxylin and eosin were used to analyze cytomorphological pattern and Zeihl Neelsen stained smears for acid fast bacilli (AFB) detection. RESULTS: 193 cases with necrotising granulomatous inflammation or positive acid fast bacilli were included. Age group 21-30 years was most common (38.3%) followed by age group 11-20 years (30.05%). Females constituted 66.3% of patients and 33.7% were male. Overall the most common pattern in present study was pattern A (Epitheloid granuloma with caseous necrosis 33.7% followed by pattern B (caseous necrosis with few scattered epitheloid histiocytes and lymphocytes) 31.1% and pattern C (caseous necrosis with suppurative inflammation) 30.6%, followed by pattern D (Caseous necrosis only) (3.6%) and pattern E (non necrotising epitheloid granuloma with positive acid fast bacilli) (1.03%). Acid fast bacilli were demonstrable in 175 cases (90.7%). Amongst the acid fast bacilli positive cases highest bacillary load 3+ grade was seen in pattern C in 6/59 (10.16%) cases. CONCLUSION: FNAC is a simple useful tool and should be attempted in all cases of lymphandenopathies. It helps in establishing a diagnosis of tubercular etiology based on its morphological patterns however demonstration of acid fast bacilli on aspirated material confirms the diagnosis.

19.
Sensors (Basel) ; 20(21)2020 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-33105863

RESUMEN

In this paper, we propose an environment perception framework for autonomous driving using state representation learning (SRL). Unlike existing Q-learning based methods for efficient environment perception and object detection, our proposed method takes the learning loss into account under deterministic as well as stochastic policy gradient. Through a combination of variational autoencoder (VAE), deep deterministic policy gradient (DDPG), and soft actor-critic (SAC), we focus on uninterrupted and reasonably safe autonomous driving without steering off the track for a considerable driving distance. Our proposed technique exhibits learning in autonomous vehicles under complex interactions with the environment, without being explicitly trained on driving datasets. To ensure the effectiveness of the scheme over a sustained period of time, we employ a reward-penalty based system where a negative reward is associated with an unfavourable action and a positive reward is awarded for favourable actions. The results obtained through simulations on DonKey simulator show the effectiveness of our proposed method by examining the variations in policy loss, value loss, reward function, and cumulative reward for 'VAE+DDPG' and 'VAE+SAC' over the learning process.

20.
Cancers (Basel) ; 12(9)2020 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-32911681

RESUMEN

Cancer cells employ various defense mechanisms against drug-induced cell death. Investigating multi-omics landscapes of cancer cells before and after treatment can reveal resistance mechanisms and inform new therapeutic strategies. We assessed the effects of navitoclax, a BCL2 family inhibitor, on the transcriptome, methylome, chromatin structure, and copy number variations of MDA-MB-231 triple-negative breast cancer (TNBC) cells. Cells were sampled before treatment, at 72 h of exposure, and after 10-day drug-free recovery from treatment. We observed transient alterations in the expression of stress response genes that were accompanied by corresponding changes in chromatin accessibility. Most of these changes returned to baseline after the recovery period. We also detected lasting alterations in methylation states and genome structure that suggest permanent changes in cell population composition. Using single-cell analyses, we identified 2350 genes significantly upregulated in navitoclax-resistant cells and derived an 18-gene navitoclax resistance signature. We assessed the navitoclax-response-predictive function of this signature in four additional TNBC cell lines in vitro and in silico in 619 cell lines treated with 251 different drugs. We observed a drug-specific predictive value in both experiments, suggesting that this signature could help guiding clinical biomarker studies involving navitoclax.

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