A note on proof of Gordon's Conjecture

Kun Du 대한수학회 2018 대한수학회보 Vol.55 No.3

In this paper, we show a proof of Gordon's Conjecture by using Qiu's labels and two new labels.

Biomimetic Designing of Functional Silk Nanotopography Using Self-assembly

Kundu, Banani,Eltohamy, Mohamed,Yadavalli, Vamsi K.,Kundu, Subhas C.,Kim, Hae-Won American Chemical Society 2016 ACS APPLIED MATERIALS & INTERFACES Vol.8 No.42

<P>In nature inorganic organic building units create multifunctional hierarchical architectures. Organic silk protein is particularly attractive in this respect because of its micro-nanoscale structural blocks that are attributed to sophisticated hierarchical assembly imparting flexibility and compressibility to designed biohybrid materials. In the present study, aqueous silk fibroin is assembled to form nano/microtopography on inorganic silica surface via a facile diffusion-limited aggregation process. This process is driven by electrostatic interaction and only possible at a specified aminated surface chemistry. The self-assembled topography depends on the age and concentration of protein solution as well as on the surface charge distribution of the template. The self-assembled silk trails closely resemble natural cypress leaf architecture, which is considered a structural analogue of neuronal cortex. This assembled surface significantly enhances anchorage of neuronal cell and cytoskeletal extensions, providing an effective nano/microtopographical cue for cellular recognition and guidance.</P>

Fluorescent carbon nano-materials from coal-based precursors: unveiling structure–function relationship between coal and nano-materials

Kundu Niloy,Sadhukhan Dhrubajyoti,Sarkar Supriya 한국탄소학회 2022 Carbon Letters Vol.32 No.3

Fluorescent carbon nano-materials with quantum confinement and edge effects have recently piqued attention in a variety of applications, including biological imaging, drug delivery, optoelectronics and sensing. These nano-materials can be synthesized from a variety of carbon-based precursors using both top-down and bottom-up methods. Coal and its derivatives typically include a vast crystalline network and condensed aromatic ring cluster, which can be easily exfoliated by chemical, electrochemical, or physical processes to produce nano-materials. As a result, they are regarded as a low-cost, abundant and efficient carbon source for the fabrication of high-yield nano-materials. Nano-materials synthesized from coal-based precursors have outstanding fluorescence, photostability, biocompatibility and low toxicity, among other properties. Their properties in optical sensors, LED devices, bio-imaging, and photo and electro-catalyst applications have already been investigated. In this review, we have highlighted current developments in the synthesis, structural properties and fluorescence properties of nano-materials synthesized from coal-based precursors.

Multicolor emissive carbon dot with solvatochromic behavior across the entire visible spectrum

Kundu, Aniruddha,Park, Byeongho,Oh, Juyeong,Sankar, K. Vijaya,Ray, Chaiti,Kim, Wook Sung,Chan Jun, Seong Elsevier 2020 Carbon Vol.156 No.-

<P><B>Abstract</B></P> <P>Carbon dots (CDs) are a new class in carbonaceous family and have instigated remarkable research interests over the past decade both from fundamental and technological point of view due to its astonishing photoluminescence (PL) property, though the underlying PL mechanisms for CD are strongly disputed. Herein, we have synthesized nitrogen functionalized CDs (N-CDs) utilizing a facile and one-step hydrothermal approach. The synthesized CDs exhibit excellent solubility in a series of organic solvents and we have extensively investigated the CD-solvent interactions to understand the solvatochromic behavior of CDs which have hardly been studied. Our CDs show excitation wavelength and solvent dependent PL across nearly the entire visible spectrum without compromising the PL quantum yield (CD shows high quantum yield for both blue and red region in some selected solvents). The origin and spectral shift of PL property in different solvents are also thoroughly studied. These observations suggest that the hydrogen bonding between N-CDs and protic solvents is the primary driving force in controlling the PL in the system whereas both dipolar interaction and hydrogen bond acceptance basicity (β) of aprotic.</P> <P>solvents are to be counted for the irregular PL behavior of CDs. Interestingly, the CD-polymer solutions also provide better quantum yield compare to the bare CD which suggests that by monitoring the interaction between CD and polymer in different solvents we can tune the PL property of CD which can find potential applications in diverse fields.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

A Multi-Level Integrator with Programming Based Boosting for Person Authentication Using Different Biometrics

Kundu, Sumana,Sarker, Goutam Korea Information Processing Society 2018 Journal of information processing systems Vol.14 No.5

A multiple classification system based on a new boosting technique has been approached utilizing different biometric traits, that is, color face, iris and eye along with fingerprints of right and left hands, handwriting, palm-print, gait (silhouettes) and wrist-vein for person authentication. The images of different biometric traits were taken from different standard databases such as FEI, UTIRIS, CASIA, IAM and CIE. This system is comprised of three different super-classifiers to individually perform person identification. The individual classifiers corresponding to each super-classifier in their turn identify different biometric features and their conclusions are integrated together in their respective super-classifiers. The decisions from individual super-classifiers are integrated together through a mega-super-classifier to perform the final conclusion using programming based boosting. The mega-super-classifier system using different super-classifiers in a compact form is more reliable than single classifier or even single super-classifier system. The system has been evaluated with accuracy, precision, recall and F-score metrics through holdout method and confusion matrix for each of the single classifiers, super-classifiers and finally the mega-super-classifier. The different performance evaluations are appreciable. Also the learning and the recognition time is fairly reasonable. Thereby making the system is efficient and effective.

Silicon dioxide nanoparticles induce COX-2 expression through activation of STAT3 signaling pathway in HaCaT cells

Kundu, Juthika,Kim, Do-Hee,Chae, In Gyeong,Lee, Jong Kwon,Lee, Sooyeun,Jeong, Chul-Ho,Chun, Kyung-Soo Elsevier 2018 Toxicology in vitro Vol.52 No.-

<P><B>Abstract</B></P> <P>Silicon dioxide nanoparticles (SiO<SUB>2</SUB>-NPs) are widely used in biomedicines and consumer products, such as sunscreens and cosmetics. However, SiO<SUB>2</SUB>-NPs can cause adverse effects on human health, depending on the size and concentration of nanoparticles. The present study was aimed at investigating the molecular mechanism underlying SiO<SUB>2</SUB>-NPs-induced inflammation in human keratinocyte (HaCaT) cells. Incubation of HaCaT cells with SiO<SUB>2</SUB>-NPs induced the expression of cyclooxygenase-2 (COX-2) mRNA and protein. Treatment of cells with SiO<SUB>2</SUB>-NPs also induced the phosphorylation, DNA binding and the reporter gene activity of signal transducer and activator of transcription 3 (STAT3). Transfection of cells with STAT3 siRNA abrogated SiO<SUB>2</SUB>-NPs-induced COX-2 expression. Moreover, SiO<SUB>2</SUB>-NPs enhanced the phosphorylation of Janus kinase2 (JAK2), Src and Akt. Pharmacological inhibition of either JAK2, Src or Akt abrogated SiO<SUB>2</SUB>-NPs-induced STAT3 transcriptional activity and the expression of COX-2. Treatment with LY294002 also attenuated SiO<SUB>2</SUB>-NPs-induced Src phosphorylation, while, JAK2 phosphorylation was not changed. In addition, SiO<SUB>2</SUB>-NPs generated reactive oxygen species (ROS) and treatment of <I>N</I>-acetyl cysteine (NAC) attenuated the phosphorylation of JAK2, Src, Akt and STAT3, as well as the expression of COX-2 in SiO<SUB>2</SUB>-NPs-treated HaCaT cells. Taken together, our study provides the first report that SiO<SUB>2</SUB>-NPs induce COX-2 expression in HaCaT cells by activating the STAT3 signaling through ROS-mediated phosphorylation of upstream kinases, Akt/Src and JAK2.</P> <P><B>Highlights</B></P> <P> <UL> <LI> This study examined the molecular mechanism of SiO2-NPs-induced inflammation in human keratinocyte (HaCaT) cells. </LI> <LI> SiO2-NPs induce the phosphorylation of JAK2, Src and Akt through ROS generation. </LI> <LI> SiO2-NPs induce COX-2 expression in HaCaT cells by activating the STAT3 signaling. </LI> </UL> </P>

Heat transfer improvement of a wet fin under transient response with a unique design arrangement aspect

Kundu, Balaram,Das, Ranjan,Wankhade, Pramod A.,Lee, Kwan-Soo Elsevier Science B.V., Amsterdam. 2018 INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER - Vol.127 No.3

Bioethanol production from detoxified hydrolysate and the characterization of oxalic acid pretreated Eucalyptus (Eucalyptus globulus) biomass

Kundu, C.,Lee, J.W. Elsevier 2016 INDUSTRIAL CROPS AND PRODUCTS Vol.83 No.-

<P>In this study, different detoxification treatments (XAD-4 resin adsorption [XAD] and electrodialysis) on oxalic acid pretreated hydrolysate were evaluated. Two different detoxification processes were applied to remove fermentation inhibitors from the oxalic acid pretreated hydrolysate of eucalyptus. The hydrolysates contain sugars (glucose, xylose, and arabinose) and inhibitors. Acetic acid was the main inhibitor in the original hydrolysate, and more total phenolic compounds were generated than hydroxymethyl furfural and furfural. The acetic acid was removed 100% by the electrodialysis process, and total phenolic compounds and furfural were effectively removed from the hydrolysate by XAD. Based on the process order, the combined electrodialysis-XAD process was more effective for ethanol fermentation compared to the combined XAD-electrodialysis process. Ethanol fermentation was successfully performed using the electrodialysis-XAD-treated hydrolysate and achieved a production of 7.83 g/L of ethanol, corresponding to an ethanol yield of 0.40 gig within 48 h. Fourier transform infrared, X-ray diffractometer, and scanning electron microscopy were used to investigate the characteristics of the raw material and pretreated biomass. The results showed that most of the hemicellulose was degraded during oxalic acid pretreatment. Therefore, the crystallinity value increased from 49.79% to 56.93%. The surface of the raw material was smooth, plump, and compact, whereas the pretreated biomass was more fragmented. (c) 2016 Elsevier B.V. All rights reserved.</P>

Bioethanol production from deacetylated yellow poplar pretreated with oxalic acid recovered through electrodialysis

Kundu, Chandan,Jeong, So-Yeon,Lee, Jae-Won Elsevier 2016 Bioresource technology Vol.208 No.-

<P><B>Abstract</B></P> <P>Electrodialysis (ED) was used to develop a multistage oxalic acid recovery and pretreatment system to produce ethanol from deacetylated yellow poplar. Pretreatment of the biomass was performed at 150°C for 42min using 0.16M oxalic acid. The efficiency of oxalic acid recovery from the hydrolysate reached up to 92.32% in all the stages. Ethanol production and ethanol yield of ED-treated hydrolysate in each stage showed a uniform pattern ranging from 6.81g/L to 7.21g/L and 0.40g/g to 0.43g/g, respectively. The results showed that efficiency of ethanol production increased when deacetylated biomass and ED process was used. Ethanol yield from the pretreated biomass using simultaneous saccharification and fermentation (SSF) was in the range of 80.59–83.36% in all the stages. The structural characterization of the pretreated biomass at each stage was investigated and structural changes were not significantly different among the various pretreated biomass.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Oxalic acid was effectively recovered by electrodialysis (ED). </LI> <LI> Reuse of oxalic acid recovered through ED was effective during multistage process. </LI> <LI> The properties of pretreated biomass on multistage process were stable and constant. </LI> <LI> Ethanol production on multistage process was stable and constant. </LI> <LI> Ethanol production increased when deacetylated biomass and ED process were used. </LI> </UL> </P>

Template mediated protein self-assembly as a valuable tool in regenerative therapy

Kundu, B,Eltohamy, M,Yadavalli, VK,Reis, RL,Kim, HW Institute of Physics Publishing Ltd 2018 Biomedical Materials Vol.13 No.4