38 research outputs found

    Stability of Bloch Oscillations in two coupled Bose-Einstein condensates

    Full text link
    We investigate analytically, the stability of Bloch waves at the boundary of the first Brillouin zone in two coupled Bose-Einstein condensates confined in an optical lattice. Contrary to the single component case, we find here two critical density regimes which determine the stability of the Bloch waves. Breakdown of Bloch oscillations appear when n1/n2Nc2, here Nc1 and Nc2 are some critical values of n1/n2. There is an intermediate regime between Nc1 and Nc2 where the Bloch oscillations are stable and the condensates behave like single particles

    Quantum Theory of a Bose-Einstein Condensate out of Equilibrium

    Full text link
    We consider the interaction between a single-mode quantized perturbing external field and a Bose-Einstein condensate (BEC) out of equilibrium. The usual Rabi type oscillations between the ground and the excited state of the coherent topological modes are observed with a Rabi frequency modified by the two-body atomic interactions. Taking into account the granular structure of the external perturbing field reveals the well know phenomena of collapse and revival of the Rabi oscillations. In particular we find that atomic interactions reduce the Rabi frequency and also affect the collapse and revival sequence.Comment: Accepted for publication in Optics communicatio

    Studies on the Analgesic Potential of leaf Extracts of Allium humile on Swiss albino mice

    Get PDF
    Allium humile is a medicinal plant found at the Alpine Himalayas of Uttarakhand at altitute of 2500-3000 meters height of sea level. In India, Allium humile, is used by local people as a spice and in ethano-medicine. In the present study, Allium humile leaves were explored for their analgesic potential on experimental model and compared to standard drugs. Allium humile at the doses of 100 mg/kg and aspirin 25 mg/kg exhibited significant (p>0.05) inhibition of the control writhes at the rate of 64.25%, 44.54%, 44.54% and 59.89% respectively when compared to that of control. Thus, methanolic extract of the plant can be fully explored for its analgesic potential which has not been reported so far. The plant extract showed a relative low toxicity hence justifies the folkloric use of plant by the local people in Western Himalayan region for curing inflammation and painful conditions

    Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

    Get PDF
    In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure fl ux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defi ned as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium ) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the fi eld understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation it is imperative to delete or knock down more than one autophagy-related gene. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways so not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field

    Global investments in pandemic preparedness and COVID-19: development assistance and domestic spending on health between 1990 and 2026

    Get PDF
    Background The COVID-19 pandemic highlighted gaps in health surveillance systems, disease prevention, and treatment globally. Among the many factors that might have led to these gaps is the issue of the financing of national health systems, especially in low-income and middle-income countries (LMICs), as well as a robust global system for pandemic preparedness. We aimed to provide a comparative assessment of global health spending at the onset of the pandemic; characterise the amount of development assistance for pandemic preparedness and response disbursed in the first 2 years of the COVID-19 pandemic; and examine expectations for future health spending and put into context the expected need for investment in pandemic preparedness. Methods In this analysis of global health spending between 1990 and 2021, and prediction from 2021 to 2026, we estimated four sources of health spending: development assistance for health (DAH), government spending, out-of-pocket spending, and prepaid private spending across 204 countries and territories. We used the Organisation for Economic Co-operation and Development (OECD)'s Creditor Reporting System (CRS) and the WHO Global Health Expenditure Database (GHED) to estimate spending. We estimated development assistance for general health, COVID-19 response, and pandemic preparedness and response using a keyword search. Health spending estimates were combined with estimates of resources needed for pandemic prevention and preparedness to analyse future health spending patterns, relative to need. Findings In 2019, at the onset of the COVID-19 pandemic, US92trillion(959·2 trillion (95% uncertainty interval [UI] 9·1–9·3) was spent on health worldwide. We found great disparities in the amount of resources devoted to health, with high-income countries spending 7·3 trillion (95% UI 7·2–7·4) in 2019; 293·7 times the 248billion(9524·8 billion (95% UI 24·3–25·3) spent by low-income countries in 2019. That same year, 43·1 billion in development assistance was provided to maintain or improve health. The pandemic led to an unprecedented increase in development assistance targeted towards health; in 2020 and 2021, 18billioninDAHcontributionswasprovidedtowardspandemicpreparednessinLMICs,and1·8 billion in DAH contributions was provided towards pandemic preparedness in LMICs, and 37·8 billion was provided for the health-related COVID-19 response. Although the support for pandemic preparedness is 12·2% of the recommended target by the High-Level Independent Panel (HLIP), the support provided for the health-related COVID-19 response is 252·2% of the recommended target. Additionally, projected spending estimates suggest that between 2022 and 2026, governments in 17 (95% UI 11–21) of the 137 LMICs will observe an increase in national government health spending equivalent to an addition of 1% of GDP, as recommended by the HLIP. Interpretation There was an unprecedented scale-up in DAH in 2020 and 2021. We have a unique opportunity at this time to sustain funding for crucial global health functions, including pandemic preparedness. However, historical patterns of underfunding of pandemic preparedness suggest that deliberate effort must be made to ensure funding is maintained

    Efficacy and evaluation of cone beam computed tomography in determining the prevalence and length of anterior loop of inferior alveolar nerve in North Indian population

    No full text
    Introduction: The section of the inferior alveolar nerve (IAN) in front of the mental foramen and just before its ramification to the incisive nerve is known as anterior loop (AL) of IAN. Surgeries in the area of the anterior mandible may violate the AL resulting in neurosensory disturbances. Cone beam computed tomography (CBCT) is a new imaging modality that provides a multidimensional view of the facial skeleton. Aim: To evaluate the efficacy of CBCT in measuring the anterior looping of IAN. Objectives: To determine the prevalence of AL of IAN using CBCT, and to determine AL length using CBCT. Materials and Methods: Out of the total 1075 reported patients, 193 study participants fulfilling the inclusion criteria constituted the sample size were assessed for estimating the prevalence and determining the length of AL of IAN. They were scanned with a suitable digital imaging system for a variety of clinical indications using appropriate Dental Imaging Software. Results: The prevalence of anterior looping was found to be 37.3% and was highest (43.5%) in the age group of 36–56 years and was found to be statistically significant. The mean length of anterior looping was found to be 3.661 mm (SD ± 1.9933) with a maximum loop length of 8.8 mm. Conclusion: CBCT provides an accurate means to determine the anterior looping of IAN, measures its length, and thereby, helps in preoperative surgical planning

    Study of lip prints: A forensic study

    No full text
    Background: Although several studies have been done on lip prints for human identification in forensic science, there is a doubt about their use in gender determination. Aims: The present study was designed to study the lip groove patterns in all the quadrants of both male and female subjects to identify the sex, based on the patterns of the grooves of the lip prints. Study Design: 300 lip prints were collected from volunteers of D. J. College of Dental Sciences and Research, Modinagar (UP). Materials and Methods: Lip prints were recorded with lip stick and transferred on to a glass slide. Statistical Analysis: Pearson chi-square test was adopted for statistical analysis and probability value (P value) was calculated. Conclusion: In our study, none of the lip prints were identical, thus confirming the role of lip prints in individual identification. According to Suzuki′s classification, Type I, II, III and IV patterns were significant in gender determination

    Classifying giant cell lesions: A review

    No full text
    Multinucleated giant cells are often encountered in oral lesions. Traditional classifications have placed a little importance on the type or histogenesis of multinucleated giant cells in grouping these lesions. The classification of giant cell lesions of the maxillofacial skeleton is the one that remains controversial. Classifying giant cell lesions of the jaw as granulomatous based solely on its location seems inappropriate. Giant cells lesions were classified based on the etiopathogenesis, origin, etiology, type, radiographic appearance and pathology of giant cells present. The rationale for this classification was based on the recent research findings regarding the histogenesis of giant cells. Multinucleated giant cells are morphologically characterized by the presence of multiple nuclei dispersed in cytoplasm. Multinucleated cells are commonly encountered in oral and maxillofacial lesions. An epidemiological study by Mohajerani et al. has reported that 6.36% of the oral biopsies received in their laboratory were multinucleated giant cells containing lesions. Classifying oral lesions with giant cells has always been problematic. However, accurate identification and categorization of these lesions based on nature, distribution and origin of giant cells is necessary. Correlation of histopathological features in relation to giant cells is required. The aim of this article is to review both the earlier and recent classification of giant cell lesions in order which would enable pathologists and oral physicians to ascertain the behavior and diagnosis of such lesions
    corecore