Differentiable Spline Approximations

The paradigm of differentiable programming has significantly enhanced the scope of machine learning via the judicious use of gradient-based optimization. However, standard differentiable programming methods (such as autodiff) typically require that the machine learning models be differentiable, limiting their applicability. Our goal in this paper is to use a new, principled approach to extend gradient-based optimization to functions well modeled by splines, which encompass a large family of piecewise polynomial models. We derive the form of the (weak) Jacobian of such functions and show that it exhibits a block-sparse structure that can be computed implicitly and efficiently. Overall, we show that leveraging this redesigned Jacobian in the form of a differentiable "layer" in predictive models leads to improved performance in diverse applications such as image segmentation, 3D point cloud reconstruction, and finite element analysis.This is a proceeding preprint from Cho, Minsu, Aditya Balu, Ameya Joshi, Anjana Deva Prasad, Biswajit Khara, Soumik Sarkar, Baskar Ganapathysubramanian, Adarsh Krishnamurthy, and Chinmay Hegde. "DIFFERENTIABLE SPLINE APPROXIMATIONS." arXiv preprint arXiv:2110.01532 (2021). doi: https://doi.org/10.48550/arXiv.2110.01532. Copyright 2021 The Authors

Isomerization behavior of aromatic azo chromophores bound to semicrystalline polymer films

The cis-trans isomerization of azo chromophores covalently bound to semicrystalline polymer films was investigated. Various azo chromophores were introduced onto the functionalized semicrystalline polymer films by a chemical transformation reaction and their isomerization behavior was investigated by UV-visible spectroscopy and a contact-angle goniometer. The thermal Z → E isomerization rate of the azo moiety covalently bound to low-density polyethylene (LDPE) and polypropylene (PP) films was determined. The rate of thermal isomerization was also compared between amorphous and semicrystalline polymer films bearing azo chromophores. The effect of the intramolecular steric factor and the nature of chromophores was studied on the thermal isomerization rate of the polymer films

Isomerization Behavior of Aromatic Azo Chromophores Bound to Semicrystalline Polymer Films

The cis-trans isomerization of azo chromophores covalently bound to semicrystalline polymer films was investigated. Various azo chromophores were introduced onto the functionalized semicrystalline polymer films by a chemical transformation reaction and their isomerization behavior was investigated by UV-visible spectroscopy and a contact-angle goniometer. The thermal Z --\u3e E isomerization rate of the azo moiety covalently bound to low-density polyethylene (LDPE) and polypropylene (PP) films was determined. The rate of thermal isomerization was also compared between amorphous and semicrystalline polymer films bearing azo chromophores. The effect of the intramolecular steric factor and the nature of chromophores was studied on the thermal isomerization rate of the polymer films. (C) 2001 John Wiley & Sons, Inc

Synthesis, spectral characterization, thermal investigation and electrochemical evaluation of benzilbis(carbohydrazone) as Cd(II) ion selective electrode

Benzil bis(carbohydrazone) (BBC) has been synthesized and structurally characterized on the basis of IR, 1H NMR, mass, UV spectra and thermogravimetric analyses. BBC has been analysed electrochemically and explored as new N, N Schiff base. It plays the role of an excellent ion carrier in the construction of cadmium(II) ion selective membrane sensor. This sensor shows very good selectivity and sensitivity towards cadmium ion over a wide variety of cations, including alkali, alkaline earth, transition and heavy metal ions. The response mechanism was discussed in the view of UV-spectroscopy and Electrochemical impedance spectroscopy (EIS). The proposed sensor was successfully used for the determination of cadmium in different chocolate samples

Lanthanum Monitoring by N,N'-1,3- phenylenedimaleimide based on Polymeric Membrane Electrode Analytical & Bioanalytical Electrochemistry

Abstract-A polymeric membrane based lanthanum selective electrode was developed using N,N'-1,3-phenylenedimaleimide. The best performance was recorded with a membrane composition of PVC: DBP: Ionophore: NaTPB as 33: 64: 2: 1 (w/w %). The Nernstian slope calculated from the calibration curve for La 3+ sensor was 18.1 mV decade -1 . The detection limit of the sensor was 3.16×10 -9 M, in the linear concentration range of 1.0×10 -2 -1.0×10 -8 M. Selectivity coefficients were calculated using Matched Potential Method. The interaction mechanism of the ionophore with different cations was estimated quantitatively by complex formation constant K f values and qualitatively by FTIR spectroscopy and UV-Vis. spectrophotometry. The electrode was successfully applied to determine the fluoride content in the mouthwash and toothpaste sample

Regulation of tubulin by triiodothyronine in hypothyroid rat brain

The effect of T<SUB>3</SUB> (triiodothyronine) on the induction of tubulin in hypothyroid developing rat brain has been examined using organ cultures of brains from late fetal, neonatal and postnatalrats. The neonatal brain displayed maximum sensitivity to T<SUB>3</SUB>. Hypothyroidism resulted in a 26% decline in the level of tubulin in the neonatal brain as opposed to a 5-15% decline in the fetal or postnatal brain. Exposure of the hypothyroi d neonatal brain to T<SUB>3</SUB> for 2 h in culture led to a 61% rise in the level of tubulin in contrast to a 41% increase seen in the case of normal brain. Total protein synthesis was not significantly affected . The preferential decline of tubulin in the neonatal hypothyroid brain, its enhanced sensitivity to T<SUB>3</SUB> compared to normal brain, and the coincidence of the period of sensitivity to that of brain maturation indicate that the regulation of the level of tubulin by T<SUB>3</SUB> in the developing brain is a natural ontogenic phenomenon

Molecular docking and physicochemical studies of 1,3-benzodioxole tagged Dacarbazine derivatives as an anticancer agent

AbstractCancer, the biggest cause of death globally, remains a tough illness despite enormous advances in therapy. In the present study, 1,3-benzodioxole-tagged dacarbazine derivates were investigated as microtubule inhibitors in order to control cancer as microtubules are involved in cell proliferation. The tubulin protein was analyzed and its structure was validated by various protein validation tools. The binding potential of 1,3-benzodioxole-based dacarbazine-tagged derivatives with tubulin was checked using molecular docking software HEX 8.0 CUDA and AutoDock Vina. Swiss ADME online Web server and pkCSM are used for studying pharmacokinetic and pharmacological studies of compounds. The docking analysis ADME studies displayed that Compounds 1 and 2 bind effectively with the tubulin protein and showed potential properties to use as a potent anticancer drug

COVID-19–Associated Misinformation Across the South Asian Diaspora: Qualitative Study of WhatsApp Messages

BackgroundSouth Asians, inclusive of individuals originating in India, Pakistan, Maldives, Bangladesh, Sri Lanka, Bhutan, and Nepal, comprise the largest diaspora in the world, with large South Asian communities residing in the Caribbean, Africa, Europe, and elsewhere. There is evidence that South Asian communities have disproportionately experienced COVID-19 infections and mortality. WhatsApp, a free messaging app, is widely used in transnational communication within the South Asian diaspora. Limited studies exist on COVID-19–related misinformation specific to the South Asian community on WhatsApp. Understanding communication on WhatsApp may improve public health messaging to address COVID-19 disparities among South Asian communities worldwide. ObjectiveWe developed the COVID-19–Associated misinfoRmation On Messaging apps (CAROM) study to identify messages containing misinformation about COVID-19 shared via WhatsApp. MethodsWe collected messages forwarded globally through WhatsApp from self-identified South Asian community members between March 23 and June 3, 2021. We excluded messages that were in languages other than English, did not contain misinformation, or were not relevant to COVID-19. We deidentified each message and coded them for one or more content categories, media types (eg, video, image, text, web link, or a combination of these elements), and tone (eg, fearful, well intentioned, or pleading). We then performed a qualitative content analysis to arrive at key themes of COVID-19 misinformation. ResultsWe received 108 messages; 55 messages met the inclusion criteria for the final analytic sample; 32 (58%) contained text, 15 (27%) contained images, and 13 (24%) contained video. Content analysis revealed the following themes: “community transmission” relating to misinformation on how COVID-19 spreads in the community; “prevention” and “treatment,” including Ayurvedic and traditional remedies for how to prevent or treat COVID-19 infection; and messaging attempting to sell “products or services” to prevent or cure COVID-19. Messages varied in audience from the general public to South Asians specifically; the latter included messages alluding to South Asian pride and solidarity. Scientific jargon and references to major organizations and leaders in health care were included to provide credibility. Messages with a pleading tone encouraged users to forward them to friends or family. ConclusionsMisinformation in the South Asian community on WhatsApp spreads erroneous ideas regarding disease transmission, prevention, and treatment. Content evoking solidarity, “trustworthy” sources, and encouragement to forward messages may increase the spread of misinformation. Public health outlets and social media companies must actively combat misinformation to address health disparities among the South Asian diaspora during the COVID-19 pandemic and in future public health emergencies

COVID-19–Associated Misinformation Across the South Asian Diaspora: Qualitative Study of WhatsApp Messages

BackgroundSouth Asians, inclusive of individuals originating in India, Pakistan, Maldives, Bangladesh, Sri Lanka, Bhutan, and Nepal, comprise the largest diaspora in the world, with large South Asian communities residing in the Caribbean, Africa, Europe, and elsewhere. There is evidence that South Asian communities have disproportionately experienced COVID-19 infections and mortality. WhatsApp, a free messaging app, is widely used in transnational communication within the South Asian diaspora. Limited studies exist on COVID-19-related misinformation specific to the South Asian community on WhatsApp. Understanding communication on WhatsApp may improve public health messaging to address COVID-19 disparities among South Asian communities worldwide.ObjectiveWe developed the COVID-19-Associated misinfoRmation On Messaging apps (CAROM) study to identify messages containing misinformation about COVID-19 shared via WhatsApp.MethodsWe collected messages forwarded globally through WhatsApp from self-identified South Asian community members between March 23 and June 3, 2021. We excluded messages that were in languages other than English, did not contain misinformation, or were not relevant to COVID-19. We deidentified each message and coded them for one or more content categories, media types (eg, video, image, text, web link, or a combination of these elements), and tone (eg, fearful, well intentioned, or pleading). We then performed a qualitative content analysis to arrive at key themes of COVID-19 misinformation.ResultsWe received 108 messages; 55 messages met the inclusion criteria for the final analytic sample; 32 (58%) contained text, 15 (27%) contained images, and 13 (24%) contained video. Content analysis revealed the following themes: "community transmission" relating to misinformation on how COVID-19 spreads in the community; "prevention" and "treatment," including Ayurvedic and traditional remedies for how to prevent or treat COVID-19 infection; and messaging attempting to sell "products or services" to prevent or cure COVID-19. Messages varied in audience from the general public to South Asians specifically; the latter included messages alluding to South Asian pride and solidarity. Scientific jargon and references to major organizations and leaders in health care were included to provide credibility. Messages with a pleading tone encouraged users to forward them to friends or family.ConclusionsMisinformation in the South Asian community on WhatsApp spreads erroneous ideas regarding disease transmission, prevention, and treatment. Content evoking solidarity, "trustworthy" sources, and encouragement to forward messages may increase the spread of misinformation. Public health outlets and social media companies must actively combat misinformation to address health disparities among the South Asian diaspora during the COVID-19 pandemic and in future public health emergencies