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Ankur Srivastava Gargi Mishra Kshitij RB Singh Jay Singh Rampal Pandey Mrituanjay D. Pandey 《Luminescence》2023,38(7):1347-1357
Rare earth metals play a conspicuous role in magnetic resonance imaging (MRI) for detecting cancerous cells. The alkali metal potassium is a neurotransmitter in the sodium–potassium pump in biomedical sciences. This unique property of rare earth metals and potassium drew our attention to carry forward this study. Therefore, in this work, previously synthesized potassium (K) complexes formed by the reflux of 4-N,N-dimethylaminobenzoic acid (DBA) and potassium hydroxide in methanol, and named [(μ2–4-N,N-dimethylaminobenzoate-κO)(μ2–4-N,N-dimethylaminobenzoic acid-κO)(4-N,N-dimethylaminobenzoic acid-κO) potassium(I) coordination polymer)] were treated hydrothermally with La2O3 nanomaterials to obtain a nanohybrid La2O3/K-complex. After that, the K-complex was analyzed using single-crystal X-ray diffraction and 1H and 13C NMR spectroscopy. In addition, the structural and morphological properties of the as-prepared nanostructured La2O3/K-complex were also characterized, which involved an investigation using X-ray diffraction (XRD)spectroscopy, Fourier transform infrared (FTIR) spectroscopy, atomic force spectroscopy (AFM), transmission electron microscopy (TEM), and energy dispersive X-ray (EDX) analysis. After this, the electrochemical redox behaviour of the synthesized nanohybrid material was studied using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Therefore, the results from these studies revealed that the as-prepared material was a La2O3/K-complex that has a promising future role in sensing various analytes, as it showed effective electrocatalytic behaviour. 相似文献
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Two silicone coatings have been evaluated for barnacle adhesion. One coating is an unfilled hydrosilation cured polydimethylsiloxane (PDMS) network, while the other is a room temperature vulcanized (RTV), filled, ethoxysiloxane cured PDMS elastomer, RTV11?. The adhesion strength of one species of barnacle, Balanus eburneus, to the hydrosilation coatings is in the range of 0.37–0.60 kg cm‐2 while the corresponding range for RTV11 is 0.64–0.90 kg cm‐2. The easier release of B. eburneus from the hydrosilation cured network compared to RTV11 is discussed in relationship to differences in bulk and surface properties. Preliminary results suggest bulk modulus may be the most important parameter in determining barnacle adhesion strength. In light or mechanical property analysis, a re‐evaluation of surface properties and chemical stability is presented. 相似文献
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PHILIP S WANG MATTHIAS ANGERMEYER GUILHERME BORGES RONNY BRUFFAERTS WAI TAT CHIU GIOVANNI DE GIROLAMO JOHN FAYYAD OYE GUREJE JOSEP MARIA HARO YUEQIN HUANG RONALD C KESSLER VIVIANE KOVESS DAPHNA LEVINSON YOSHIBUMI NAKANE MARK A OAKLEY BROWN JOHAN H ORMEL JOSé POSADA-VILLA SERGIO AGUILAR-GAXIOLA JORDI ALONSO SING LEE STEVEN HEERINGA BETH-ELLEN PENNELL SOMNATH CHATTERJI T. BEDIRHAN üSTüN 《World psychiatry》2007,6(3):177-185
Data are presented on patterns of failure and delay in making initial treatment
contact after first onset of a mental disorder in 15 countries in the World
Health Organization (WHO)''s World Mental Health (WMH) Surveys. Representative
face-to-face household surveys were conducted among 76,012 respondents aged
18 and older in Belgium, Colombia, France, Germany, Israel, Italy, Japan,
Lebanon, Mexico, the Netherlands, New Zealand, Nigeria, People''s Republic
of China (Beijing and Shanghai), Spain, and the United States. The WHO Composite
International Diagnostic Interview (CIDI) was used to assess lifetime DSM-IV
anxiety, mood, and substance use disorders. Ages of onset for individual disorders
and ages of first treatment contact for each disorder were used to calculate
the extent of failure and delay in initial help seeking. The proportion of
lifetime cases making treatment contact in the year of disorder onset ranged
from 0.8 to 36.4% for anxiety disorders, from 6.0 to 52.1% for mood disorders,
and from 0.9 to 18.6% for substance use disorders. By 50 years, the proportion
of lifetime cases making treatment contact ranged from 15.2 to 95.0% for anxiety
disorders, from 7.9 to 98.6% for mood disorders, and from 19.8 to 86.1% for
substance use disorders. Median delays among cases eventually making contact
ranged from 3.0 to 30.0 years for anxiety disorders, from 1.0 to 14.0 years
for mood disorders, and from 6.0 to 18.0 years for substance use disorders.
Failure and delays in treatment seeking were generally greater in developing
countries, older cohorts, men, and cases with earlier ages of onset. These
results show that failure and delays in initial help seeking are pervasive
problems worldwide. Interventions to ensure prompt initial treatment contacts
are needed to reduce the global burdens and hazards of untreated mental disorders. 相似文献
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Rajendra P Sujatha H Devendranath D Gunasekaran B Sashidhar R Subramanyam C Channakeshava 《Biomagnetic research and technology》2004,2(1):1
BACKGROUND: There are several reports that indicate a linkage between exposure to power frequency (50 - 60 Hz) magnetic fields with abnormalities in the early embryonic development of the chicken. The present study was designed to understand whether power frequency electromagnetic fields could act as an environmental insult and invoke any neurochemical or toxicological changes in developing chick embryo model. METHODS: Fertilized chicken eggs were subjected to continuous exposure to magnetic fields (50 Hz) of varying intensities (5, 50 or 100 microT) for a period of up to 15 days. The embryos were taken out of the eggs on day 5, day 10 and day 15. Neurochemical (norepinephrine and 5-hydroxytryptamine) and amino acid (tyrosine, glutamine and tryptophan) contents were measured, along with an assay of the enzyme glutamine synthetase in the brain. Preliminary toxicological investigations were carried out based on aminotransferases (AST and ALT) and lactate dehydrogenase activities in the whole embryo as well as in the liver. RESULTS: The study revealed that there was a significant increase (p < 0.01 and p < 0.001) in the level of norepinephrine accompanied by a significant decrease (p < 0.01 and p < 0.001) in the tyrosine content in the brain on day 15 following exposure to 5, 50 and 100 microT magnetic fields. There was a significant increase (p < 0.001) in glutamine synthetase activity resulting in the significantly enhanced (p < 0.001) level of glutamine in the brain on day 15 (for 100 microT only). The possible mechanisms for these alterations are discussed. Further, magnetic fields had no effect on the levels of tryptophan and 5-hydroxytryptamine in the brain. Similarly, there was no effect on the activity of either aminotransferases or lactate dehydrogenase in the whole embryo or liver due to magnetic field exposure. CONCLUSIONS: Based on these studies we conclude that magnetic field-induced changes in norepinephrine levels might help explain alterations in the circadian rhythm, observed during magnetic field stress. Also, the enhanced level of glutamine can act as a contributing factor for developmental abnormalities. 相似文献
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Background
Many musculoskeltal injuries in the workplace have been attributed to the repetitive loading of muscle and soft tissues. It is not disputed that muscular fatigue is a risk factor for musculoskeltal injury, however the disparity between gender with respect to muscular fatigability and rate of recovery is not well understood. Current health and safety guidelines do not account for sex differences in fatiguability and may be predisposing one gender to greater risk. The purpose of this study was to quantify the sex differences in fatigue development and recovery rate of lower and upper body musculature after repeated bouts of sustained isometric contractions.Methods
Twenty-seven healthy males (n = 12) and females (n = 15) underwent bilateral localized fatigue of either the knee extensors (male: n = 8; female: n = 8), elbow flexors (male: n = 8; female: n = 10), or both muscle groups. The fatigue protocol consisted of ten 30-second sub-maximal isometric contractions. The changes in maximum voluntary contraction (MVC), electrically evoked twitches, and motor unit activation (MUA) were assessed along with the ability to control the sustained contractions (SLP) during the fatigue protocol using a mixed four-factor repeated measures ANOVA (gender × side × muscle × time) design with significance set at p < 0.05.Results
There was a significant loss of MVC, MUA, and evoked twitch amplitude from pre- to post-fatigue in both the arms and legs. Males had greater relative loss of isometric force, a higher rate of fatigue development, and were less capable of maintaining the fatiguing contractions in the legs when compared to the females.Conclusion
The nature of the induced fatigue was a combination of central and peripheral fatigue that did not fully recover over a 45-minute period. The results appear to reflect sex differences that are peripheral, and partially support the muscle mass hypothesis for explaining differences in muscular fatigue.8.
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Megasporogenesis in Taxus led to a T-shaped tetrad, the mitochondriaand plastids being largely confined to the chalazal megaspore,the only spore to show further development. Germination of themegaspore followed very soon after its formation. The femalegametophyte was initially coenocytic but after about one monthit became cellular, new walls arising between the nuclei inpositions marked out by accumulations of cisternae of endoplasmicreticulum. No secondary spindles or other formsof microtubular participation in the siting of these walls couldbe detected. The development of the archegonia could not be resolved withcertainty, but it seemed likely that the cell analogous to thecentral cell of the pteridophyte archegonium eventually becamethe egg cell. The cytoplasm of the egg cell was clearly zoned.Prominent in the outer cytoplasm were granular bodies, 25µm in diameter, identifiable with the grandes inclusionsdescribed from the egg cells of conifers. The evidence pointedto their being derived from hypertrophied plastids which hadencapsulated part of the cytoplasm, a view strengthened by thecomplete absence of recognizable plastids from the mature cell.Bundles of microtubules radiating from the nuclear envelopewere a conspicuous feature, possibly stabilizing the zonationof the cytoplasm. Megasporogenesis, Taxus baccata, egg cell, grandes inclusions 相似文献
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