25 research outputs found
Python Implementation of intelligent system for Quality Control of Argo Floats using Alpha Convex Hull
In each research field, quality control is the crucial part in order to ensure that the data collected is trustworthy. Quality control management helps in detecting abnormal behavior, monitor the health of detecting instruments. Argo Float is an ocean instrument which gives a lot of information regarding the conditions of the ocean. The information obtained has its value only if the quality of the parameter measuring procedure involves good quality tools. So, maintaining the quality of the procedure is as important as analyzing the obtained data. The salinity and the temperature data from Argo floats which collect data from in situ regions of ocean need to be scrutinized for anomalous values and examined to find out the reason behind the abnormal values recorded using a new method proposed by using Alpha convex hull. The data collected is used to construct an alpha shape polygon which is fine tuned to obtain best possible results. This method segregates by representing good data inside the polygon and the bad data outside the polygon. The proposed intelligent system is observed to detect the anomalous data occurring due to various problems such as sensor corrosion, bias ,spikes etc. This method aims to perform quality control for oceanographic data of argos at present but aims to work on different sources. The main advantages of the proposed system can be seen as the ability to identify anomalous data from in situ bulk data in minimal steps and to be applicable for cumulative data of various depths together
Distinct Functions for Mammalian CLASP1 and-2 During Neurite and Axon Elongation
Mammalian cytoplasmic linker associated protein 1 and -2 (CLASP1 and -2) are
microtubule (MT) plus-end tracking proteins that selectively stabilize MTs at the
edge of cells and that promote MT nucleation and growth at the Golgi, thereby
sustaining cell polarity. In vitro analysis has shown that CLASPs are MT growth
promoting factors. To date, a single CLASP1 isoform (called CLASP1α) has been
described, whereas three CLASP2 isoforms are known (CLASP2α, -β, and -γ).
Although CLASP2β/γ are enriched in neurons, suggesting isoform-specific functions,
it has been proposed that during neurite outgrowth CLASP1 and -2 act in a
redundant fashion by modulating MT dynamics downstream of glycogen synthase
kinase 3 (GSK3). Here, we show that in differentiating N1E-115 neuroblastoma cells
CLASP1 and CLASP2 differ in their accumulation at MT plus-ends and display
different sensitivity to GSK3-mediated phosphorylation, and hence regulation. More
specifically, western blot (WB) analysis suggests that pharmacological inhibition of
GSK3 affects CLASP2 but not CLASP1 phosphorylation and fluorescence-based
microscopy data show that GSK3 inhibition leads to an increase in the number of
CLASP2-decorated MT ends, as well as to increased CLASP2 staining of individual MT
ends, whereas a reduction in the number of CLASP1-decorated ends is observed. Thus,
in N1E-115 cells CLASP2 appears to be a prominent target of GSK3 while CLASP1 is
less sensitive. Surprisingly, knockdown of either CLASP causes phosphorylation of
GSK3, pointing to the existence of feedback loops between CLASPs and GSK3. In
addition, CLASP2 depletion also leads to the activation of protein kinase C (PKC).
We found that these differences correlate with opposite functions of CLASP1 and
CLASP2 during neuronal differentiation, i.e., CLASP1 stimulates neurite extension,
whereas CLASP2 inhibits it. Consistent with knockdown results in N1E-115 cells, primary
Clasp2 knockout (KO) neurons exhibit early accelerated neurite and axon outgrowth,
showing longer axons than control neurons. We propose a model in which neurite
outgrowth is fine-tuned by differentially posttranslationally modified isoforms of CLASPs
acting at distinct intracellular locations, thereby targeting MT stabilizing activities of the
CLASPs and controlling feedback signaling towards upstream kinases. In summary,
our findings provide new insight into the roles of neuronal CLASPs, which emerge as
regulators acting in different signaling pathways and locally modulating MT behavior
during neurite/axon outgrowth
A Genetic Screen for Anchorage-Independent Proliferation in Mammalian Cells Identifies a Membrane-Bound Neuregulin
Anchorage-independent proliferation is a hallmark of oncogenic transformation and is thought to be conducive to proliferation of cancer cells away from their site of origin. We have previously reported that primary Schwann cells expressing the SV40 Large T antigen (LT) are not fully transformed in that they maintain a strict requirement for attachment, requiring a further genetic change, such as oncogenic Ras, to gain anchorage-independence. Using the LT-expressing cells, we performed a genetic screen for anchorage-independent proliferation and identified Sensory and Motor Neuron Derived Factor (SMDF), a transmembrane class III isoform of Neuregulin 1. In contrast to oncogenic Ras, SMDF induced enhanced proliferation in normal primary Schwann cells but did not trigger cellular senescence. In cooperation with LT, SMDF drove anchorage-independent proliferation, loss of contact inhibition and tumourigenicity. This transforming ability was shared with membrane-bound class III but not secreted class I isoforms of Neuregulin, indicating a distinct mechanism of action. Importantly, we show that despite being membrane-bound signalling molecules, class III neuregulins transform via a cell intrinsic mechanism, as a result of constitutive, elevated levels of ErbB signalling at high cell density and in anchorage-free conditions. This novel transforming mechanism may provide new targets for cancer therapy
Acetylcholine Receptor (AChR) Clustering Is Regulated Both by Glycogen Synthase Kinase 3β (GSK3β)-dependent Phosphorylation and the Level of CLIP-associated Protein 2 (CLASP2) Mediating the Capture of Microtubule Plus-ends*
Synthetic lethal screening in Drosophila melanogaster reveals novel kinases that can suppress Pten loss-of-function in vivo
The Testing Database as Pandemic Technology: Reflections on the COVID-19 Response in India
This article examines the COVID-19 response in India, viewing it as deeply enmeshed in the dynamics of the ‘database’ as an emerging technology of governmentality. Databases aim to translate entire populations into units of information abstracted from social identities and local specificities. In the context of the coronavirus pandemic, bureaucratic state systems attempt to manage and respond to the health crisis via databases collating testing data across the country. Problematising COVID-19 testing databases, we delve into the logic of database governance. We find that as a tool of governance the database falters in its attempts to compress complex identities and locations into de-contextualised units of information. As the complexity of lived reality interrupts the logic of databasing, state discourse on ‘unintended consequences’, ‘leakages’, ‘duplication’, and ‘reconciliation’ processes in the management of databases abounds and the ambivalence of databases becomes manifest in the COVID-19 response. In this article, we use secondary data to understand how testing databases intervene and interact with complex realities to establish bureaucratic order around a pandemic. We posit that COVID-19 testing databases should be understood as being embedded in emerging database governmentalities that supplant care of the population with the maintenance of databases
Distinct functions for mammalian CLASP1 and -2 during neurite and axon elongation
Mammalian cytoplasmic linker associated protein 1 and -2 (CLASP1 and -2) are microtubule (MT) plus-end tracking proteins that selectively stabilize MTs at the edge of cells and that promote MT nucleation and growth at the Golgi, thereby sustaining cell polarity. In vitro analysis has shown that CLASPs are MT growth promoting factors. To date, a single CLASP1 isoform (called CLASP1α) has been described, whereas three CLASP2 isoforms are known (CLASP2α, -β, and -γ). Although CLASP2β/γ are enriched in neurons, suggesting isoform-specific functions, it has been proposed that during neurite outgrowth CLASP1 and -2 act in a redundant fashion by modulating MT dynamics downstream of glycogen synthase kinase 3 (GSK3). Here, we show that in differentiating N1E-115 neuroblastoma cells CLASP1 and CLASP2 differ in their accumulation at MT plus-ends and display different sensitivity to GSK3-mediated phosphorylation, and hence regulation. More specifically, western blot (WB) analysis suggests that pharmacological inhibition of GSK3 affects CLASP2 but not CLASP1 phosphorylation and fluorescence-based microscopy data show that GSK3 inhibition leads to an increase in the number of CLASP2-decorated MT ends, as well as to increased CLASP2 staining of individual MT ends, whereas a reduction in the number of CLASP1-decorated ends is observed. Thus, in N1E-115 cells CLASP2 appears to be a prominent target of GSK3 while CLASP1 is less sensitive. Surprisingly, knockdown of either CLASP causes phosphorylation of GSK3, pointing to the existence of feedback loops between CLASPs and GSK3. In addition, CLASP2 depletion also leads to the activation of protein kinase C (PKC). We found that these differences correlate with opposite functions of CLASP1 and CLASP2 during neuronal differentiation, i.e., CLASP1 stimulates neurite extension, whereas CLASP2 inhibits it. Consistent with knockdown results in N1E-115 cells, primary Clasp2 knockout (KO) neurons exhibit early accelerated neurite and axon outgrowth, showing longer axons than control neurons. We propose a model in which neurite outgrowth is fine-tuned by differentially posttranslationally modified isoforms of CLASPs acting at distinct intracellular locations, thereby targeting MT stabilizing activities of the CLASPs and controlling feedback signaling towards upstream kinases. In summary, our findings provide new insight into the roles of neuronal CLASPs, which emerge as regulators acting in different signaling pathways and locally modulating MT behavior during neurite/axon outgrowth.European Commission (FP6-2002-MOBILITY11, grant agreement: ID: 517582
Acetylcholine Receptor (AChR) Clustering Is Regulated Both by Glycogen Synthase Kinase 3? (GSK3?)-dependent Phosphorylation and the Level of CLIP-associated Protein 2 (CLASP2) Mediating the Capture of Microtubule Plus-ends.
CLASP2 safeguards hematopoietic stem cell properties during mouse and fish development
Hematopoietic stem cells (HSCs) express a large variety of cell surface receptors that are associated with acquisition of self-renewal and multipotent properties. Correct expression of these receptors depends on a delicate balance between cell surface trafficking, recycling, and degradation and is controlled by the microtubule network and Golgi apparatus, whose roles have hardly been explored during embryonic/fetal hematopoiesis. Here we show that, in the absence of CLASP2, a microtubule-associated protein, the overall production of HSCs is reduced, and the produced HSCs fail to self-renew and maintain their stemness throughout mouse and zebrafish development. This phenotype can be attributed to decreased cell surface expression of the hematopoietic receptor c-Kit, which originates from increased lysosomal degradation in combination with a reduction in trafficking to the plasma membrane. A dysfunctional Golgi apparatus in CLASP2-deficient HSCs seems to be the underlying cause of the c-Kit expression and signaling imbalance