590 research outputs found
Non-Gaussianity and direction dependent systematics in HST key project data
Two new statistics, namely and , based on
extreme value theory, were derived in \cite{gupta08,gupta10}. We use these
statistics to study direction dependence in the HST key project data which
provides the most precise measurement of the Hubble constant. We also study the
non-Gaussianity in this data set using these statistics. Our results for
show that the significance of direction dependent systematics
is restricted to well below one confidence limit, however, presence of
non-Gaussian features is subtle. On the other hand statistic,
which is more sensitive to direction dependence, shows direction dependence
systematics to be at slightly higher confidence level, and the presence of
non-Gaussian features at a level similar to the statistic.Comment: 6 pages, 4 figures; accepted for publication in MNRA
METHYL-CPG BINDING PROTEINS MEDIATE OCTOPAMINERGIC REGULATION OF COMPLEX BEHAVIORAL TRAITS
An organism’s survivability in the natural world is contingent to its ability to respond rapidly and appropriately to various cues and challenges in its physical and social environment. The dynamicity of various environmental and social factors necessitates plasticity in morphological, physiological and behavioral systems – both at the level of an individual organism and that of a species. For more than century, natural selection of existing genetic variation in populations has helped us understand such plasticity across generations. However, recent years have seen a re-emergence of somewhat contentious quasi-Lamarckian framework with which organisms can reliably transmit acquired traits to subsequent generations in response to changes in external conditions. Whether or not it can be categorized as such, a stable transgenerational transmission of acquired alterations in epigenetic code, including methylation patterns and small RNA molecules, associated with behavioral and physiological, and I use the term here loosely, ‘adaptations’ for up to three generations has indeed been demonstrated in a number of species. The focus on methyl-binding proteins in this dissertation is guided by a motivation to advance our understanding of such epigenetic systems in one of the most extensively used model systems in biological and biomedical research – Drosophila.
In contrast to the vast body of literature on the genetics, physiology, ecology, and neurobiology of Drosophila, methylation and methylation-associated processes represent one of the few relatively unexplored territories in this system. This certainly hasn’t been for the lack of trying (see section 1.8). Consistent with their role in other species, Drosophila MBD proteins have been implicated in dynamic regulation of chromatin architecture and spatiotemporal regulation of gene expression. However, methylationdependence of their functions and their contribution to the overall organismal behavior remains equivocal.
In this dissertation, I explore the role of the conserved methyl-CpG binding (MBD) proteins in the regulation of octopaminergic (OA) systems that are associated with a number of critical behaviors such as aggression, courtship, feeding, locomotion, sleep, and learning and memory. In chapter II, I, along with my colleagues, demonstrate functional conservation of human and Drosophila MBD-containing proteins. We show – (a) that a well-characterized human protein – MeCP2 – can regulate amine neuron output in Drosophila through MBD domain, (b) that endogenous MBD proteins in Drosophila regulate OA sleep circuitry in a manner similar to human MeCP2, and (c) that human and Drosophila MBD proteins may share a select few genomic binding sites on larval polytene chromosomes. In chapter III, we describe a novel function of these chromatin modifiers in the regulation of social behaviors, including aggression and courtship. Returning to the issue of methylation, we demonstrate an interaction effect between induced-DNA hypermethylation and MBD-function in context of aggression and intermale courtship.
Species – and sex–specific behaviors such as courtship and aggression rely on an organism’s ability to reliably discriminate between species, sexes and social hierarchy of interacting partners, and adjust to the dynamic shifts in sensory and behavioral feedback cues. At the level of an individual organism, such behavioral flexibility is often achieved by modulating the strength and directionality of neural network outputs which endows a limited biological circuit the capacity to generate variable outputs and adds richness to the repertoire of behaviors it can display (Marder, 2012). The role of MBD proteins discussed in this dissertation highlights a mechanism that couples chromatin remodeling and OA neuromodulation in context-dependent decision-making processes
Investigating checkpoint inhibitor-induced gastrointestinal disease: comparisons with idiopathic ulcerative colitis and health
In the last decade, immunotherapy with anti-PD1 and anti-CTLA4 drugs has revolutionized the treatment of metastatic cancer. A significant proportion of patients given these checkpoint inhibitors develop off-target inflammation in the colon (checkpoint inhibitor-induced colitis, CC). Ulcerative colitis (UC) is a well-characterized multisystem disorder, propagated by a combination of barrier defects, immune dysfunction and a disordered microbiome, all on a background of genetic susceptibility. The underlying mechanisms of both checkpoint inhibitor-induced colitis and ulcerative colitis remain poorly understood, with a significant proportion of patients failing therapy. Using clinical data, next-generation single-cell RNA sequencing, unbiased spatial transcriptomics and organoid model systems, we elucidate clinically relevant patterns of cellular behaviour across blood, epithelium, stroma and immune populations. We describe and characterize novel disease-specific cell populations and cellular interactions in tissue ‘microdomains’ with functional relevance. Our work has implications for therapeusis as well as puts forward a new approach for identifying drug-bound cells in vivo
Impact of Competing Force of Motivational Factors on Employees at Work Place
The present research was conducted to ascertain the competing force of push and pull factors on employee motivation. This study is an assessment of this purpose used deductive approach in which a qualitative survey was carried out among engineers of North India. The survey was intended to get their responses on what they feel is (are) the best factors that could motivate them in a list of 10 push and 13 pull factors. In this light the study sets to identify the most ranked factors for motivation. The analysis from the empirical findings show that need of position and power and need of security were the most push ranked factors and interest and position or power were the most pull ranked factors for male engineers. While, the need of security and achievement were the most push ranked factors and working conditions and appreciation by management were the most pull ranked factors by female engineers. Keywords: Pull, Push, Motivation, Competing Force, Employee
A VLSI DSP DESIGN AND IMPLEMENTATION OF COMB FILTER USING UN-FOLDING METHODOLOGY
In signal processing, a comb filter adds a delayed version of a signal to itself, causing constructive and destructive interference. Comb filters are used in a variety of signal processing applications that is Cascaded Integrator-Comb filters, Audio effects, including echo, flanging, and digital waveguide synthesis and various other applications. Comb filter when implemented has lower through-put as the sample period can not be achieved equal to the iteration bound because node computation time of comb filter is larger than the iteration bound. Hence throughput remains less. This paper present the comb filter using one of the methodology needed to design custom or semi custom VLSI circuits named as Un-Folding which increases the throughput of the comb filter. Un-Folding is a transformation technique that can be applied to a DSP program to create a new program describing more than one iteration of the original program. It can unravel hidden con-currency in digital signal processing systems described by DFGs. Therefore, unfolding has been used for the sample period reduction of the comb filter for its higher throughput
A VLSI DSP DESIGN AND IMPLEMENTATION OF ALL POLE LATTICE FILTER USING RETIMING METHODOLOGY
All pole lattice fil ters are used in a variety of signal processing applications that is speech processing, adaptive filters and various other applications. The implementation of lattice f i l t e r requires more clock period hence low speed. There are various transformation technique pr es ent for design of high-speed or low-area or lowpower implementations. This paper presents design of high-speed (smaller clock period) implementation of 8th order all pole lattice filter using the methodology named as Retiming. Retiming reduces the clock period of the circuit, reducing the number of registers in the circuit, reducing the power consumption of the circuit. Therefore, retiming has been used to reduce the clock period of all pole lattice filters and it increases the speed of the system
Asymmetric severity of diabetic retinopathy in Waardenburg syndrome: response to authors
Aditi Gupta, Rajiv Raman, Tarun SharmaShri Bhagwan Mahavir Department of Vitreoretinal Services, Sankara Nethralaya, Chennai, Tamil Nadu, IndiaWe read with great interest the recent article by Kashima et al,1 in which the authors report a case of asymmetric severity of diabetic retinopathy in Waardenburg syndrome. We want to highlight some concerns regarding this report. Previous reports have described many systemic and local factors associated with the development of asymmetric diabetic retinopathy.2,3 These include myopia ≥5 D, anisometropia >1 D, amblyopia, unilateral elevated intraocular pressure, complete posterior vitreous detachment, unilateral carotid artery stenosis, ocular ischemic syndrome, and chorioretinal scarring.2,3 In any suspected case of asymmetric diabetic retinopathy, it is prudent to rule out the abovementioned factors first. In the present case, although the authors clearly mention the absence of internal carotid and ophthalmic artery obstruction on magnetic resonance angiography, it would have been more informative if the authors had also provided the refractive error, intraocular pressure, and posterior vitreous detachment status of both the eyes.Likewise, it would have been useful to note the arm-retina time and retinal arteriovenous filling time in both the eyes on fundus fluorescein angiography, which is usually used to diagnose ocular ischemic syndrome by monitoring extension of the retinal circulation time, including time of blood circulation from the arm to the retina and the retinal arteriovenous filling time.4,5 The mere absence of internal carotid obstruction on magnetic resonance angiography cannot rule out the presence of ocular ischemic syndrome because, rarely, ocular ischemic syndrome can also occur secondary to other causes, such as arteritis.6,7 Comparing the arm-retina time and retinal arteriovenous filling time on fundus fluorescein angiography in both the eyes would be more helpful to rule out ocular ischemic syndrome
- …