Overview of Childhood Cancers at a Regional Cancer Centre in North-East India

Hazarika, Munlima,Krishnatreya, Manigreeva,Bhuyan, Cidananda,Saikia, Bhargab Jyoti,Kataki, Amal Chandra,Nandy, Pintu,Hazarika, Monalisha,Roy, Partha Sarathi Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.18

Childhood cancers are relatively uncommon in comparison to adult cancers. There is no literature available to shed light on clinic-pathological types and patterns of care for childhood cancers in our population in North-East India. In this analysis we therefore tried to determine the common childhood cancers diagnosed in our institute, clinical profile of the patients, types of treatment and compliance, and median survival estimates. Leukemia was most common, followed by retinoblastoma, central nervous system tumours and lymphomas. Ascertaining the clinic-pathological profile of childhood cancers in our population is essential for allocation and management of resources for this small but important group of patients.

HYPERCYCLIC OPERATOR WEIGHTED SHIFTS

Hazarika, Munmun,Arora, S.C. Korean Mathematical Society 2004 대한수학회보 Vol.41 No.4

We consider bilateral operator weighted shift T on $L^2$(K) with weight sequence ${[A_{n}]_{n=-{\infty}}}^{\infty}$ of positive invertible diagonal operators on K. We give a characterization for T to be hypercyclic, and show that the conditions are far simplified in case T is invertible.

The modulatory effect of Hydrocotyle sibthorpioides in attenuating the aluminium chloride induced neurotoxicity in rat brain

Hazarika Iswar,Mukundan Geetha Kannoth,Sundari Sivakami P.,Das Anju 경희대학교 융합한의과학연구소 2022 Oriental Pharmacy and Experimental Medicine Vol.22 No.1

Hydrocotyle sibthorpioides Lam. (Family: Araliaceae) is used widely in the preparation of food in different cuisines of the world. The study was designed to explore the protective effect of different standardised extracts of H. sibthorpioides on the AlCl3 induced neurotoxicity in Alzheimeric rats. When AlCl3 at a dose of 100 mg/kg body weight was administered i.p. for 60 days showed a significant increase in aluminium (Al) level, acetylcholinesterase (AChE) level and protein expressions of amyloid precursor proteins, β and γ secretase, and β-amyloid (Aβ1–42) in the cortex and hippocampus comparing to the control. Moreover, there was a significant reduction in locomotor activity, muscle coordination and cognition and memory. On the other hand, animals treated with chloroform and methanolic extracts of H. sibthorpiodes given at 200 and 100 mg/ kg body weight orally with AlCl3 altered the behavioural impairment caused by Al and Al concentration, activity of AChE, synthesis molecules of Aβ generation. The report of histological studies in hippocampus and cortex supported the neuropro- tective role of chloroform and a methanolic extract of H. sibthorpioides, which conserved a normal histoarchitecture pattern of cortex and hippocampus. Finally, it can be concluded that chloroform and methanolic extract of H sibthorpioides can alter memory loss induced by aluminum toxicity by enhancing AChE activity and by its involvement in amyloidogenic pathway.

Woven Kevlar Fiber/Polydimethylsiloxane/Reduced Graphene Oxide Composite-Based Personal Thermal Management with Freestanding Cu-Ni Core-Shell Nanowires

Hazarika, Ankita,Deka, Biplab K.,Kim, DoYoung,Jeong, Hoon Eui,Park, Young-Bin,Park, Hyung Wook American Chemical Society 2018 Nano letters Vol.18 No.11

<P>Thermotherapy is a widespread technique that provides relief for muscle spasms and joint injuries. A great deal of energy is used to heat the surrounding environment, and heat emitted by the human body is wasted on our surroundings. Herein, a woven Kevlar fiber (WKF)-based personal thermal management device was fabricated by directly growing vertical copper-nickel (Cu-Ni) nanowires (NWs) on the WKF surface using a hydrothermal method. The treated WKF was combined with reduced graphene oxide (rGO) dispersed in polydimethylsiloxane (PDMS) to form composites using vacuum-assisted resin transfer molding (VARTM). This WKF-based personal thermal management system contained a conductive network of metallic NWs and rGO that promoted effective Joule heating and reflected back the infrared (IR) radiation emitted by the human body. It thus behaved as a type of thermal insulation. The Cu-Ni NWs were synthesized with a tunable Ni layer on Cu core NWs to enhance the oxidation resistance of the Cu NWs. The combined effect of the NW networks and rGO enabled a surface temperature of 70 °C to be attained on application of 1.5 V to the composites. The Cu<SUB>3</SUB>Ni<SUB>1</SUB>-WKF/PDMS provided 43% more thermal insulation and higher IR reflectance than bare WKF/PDMS. The absorbed impact energy and tensile strength was highest for the Cu<SUB>1</SUB>Ni<SUB>3</SUB>- and rGO-integrated WKF/PDMS samples. Those Cu-Ni NWs having higher Ni contents displayed better mechanical properties and those with higher Cu contents showed higher Joule heating performance and IR reflectivity at a given rGO loading. The composite shows sufficient breathability and very high durability. The high flexibility of the composites and their ability to generate sufficient heat during various human motions ensures their suitability for wearable applications.</P> [FIG OMISSION]</BR>

ON HYPONORMALITY OF TOEPLITZ OPERATORS WITH POLYNOMIAL AND SYMMETRIC TYPE SYMBOLS

Hazarika, Munmun,Phukon, Ambeswar Korean Mathematical Society 2011 대한수학회보 Vol.48 No.3

In [6], it was shown that hyponormality for Toeplitz operators with polynomial symbols can be reduced to classical Schur's algorithm in function theory. In [6], Zhu has also given the explicit values of the Schur's functions ${\Phi}_0$, ${\Phi}_1$ and ${\Phi}_2$. Here we explicitly evaluate the Schur's function ${\Phi}_3$. Using this value we find necessary and sufficient conditions under which the Toeplitz operator $T_{\varphi}$ is hyponormal, where ${\varphi}$ is a trigonometric polynomial given by ${\varphi}(z)$ = ${\sum}^N_{n=-N}a_nz_n(N{\geq}4)$ and satisfies the condition $\bar{a}_N\(\array{a_{-1}\\a_{-2}\\a_{-4}\\{\vdots}\\a_{-N}}\)=a_{-N}\;\(\array{\bar{a}_1\\\bar{a}_2\\\bar{a}_4\\{\vdots}\\\bar{a}_N}\)$. Finally we illustrate the easy applicability of the derived results with a few examples.

Adult Non Hodgkin's Lymphoma Patients: Experience from a Tertiary Care Cancer Centre in North East India

Hazarika, Munlima,Iqbal, Asif,Krishnatreya, Manigreeva,Sharma, Jagannath Dev,Bhuyan, Chidananda,Saikia, Bhargab Jyoti,Roy, Partha Sarathi,Das, Rashmi,Nandy, Pintu,Kataki, Amal Chandra Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.7

There is paucity of data on non Hodgkin's lymphoma (NHL) from our population in North-East India. In this retrospective study, patients were consecutively followed-up to see the clinic-pathological pattern of NHL, various responses, and pattern of relapses to first line treatment with chemotherapy. All patients in the present study received standard regimen of cyclophosphamde, doxorubicin, vincristine, prednisolone (CHOP) with or without rituximab (R-CHOP) as per our institutional protocol as first line therapy. Our study has shown that, in our adult population, the majority of NHL cases present with stage II and stage III disease and extra nodal involvement, B-cell lymphomas and diffuse large cell lymphomas being the most common subtypes. International prognostic index was a significant factor for varied responses to treatment. The majority of relapses after complete remission occurred in the first year.

Fabrication and Synthesis of Highly Ordered Nickel Cobalt Sulfide Nanowire-Grown Woven Kevlar Fiber/Reduced Graphene Oxide/Polyester Composites

Hazarika, Ankita,Deka, Biplab K.,Kim, DoYoung,Roh, Hyung Doh,Park, Young-Bin,Park, Hyung Wook American Chemical Society 2017 ACS APPLIED MATERIALS & INTERFACES Vol.9 No.41

<P>Well-aligned NiCo2S4 nanowires, synthesized hydro thermally on the surface of woven Kevlar fiber (WKF), were used to fabricate composites with reduced graphene oxide (rGO) dispersed in polyester resin (PES) by means of vacuum-assisted resin transfer molding. The NiCo2S4 nanowires were synthesized with three precursor concentrations. Nanowire growth was characterized using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Hierarchical and high growth density of the nanowires led to exceptional mechanical properties of the composites. Compared with bare WKF/PES, the tensile strength and absorbed impact energy were enhanced by 96.2% and 92.3%, respectively, for WKF/NiCo2S4/rGO (1.5%)/PES. The synergistic effect of NiCo2S4 nanowires and rGO in the fabricated composites improved the electrical conductivity of insulating WKF/PES composites, reducing the resistance to similar to 10(3) Omega. Joule heating performance depended strongly on the precursor concentration of the nanowires and the presence of rGO in the composite. A maximum surface temperature of 163 degrees C was obtained under low-voltage (5 V) application. The Joule heating performance of the composites was demonstrated in a surface deicing experiment; we observed that 17 g of ice melted from the surface of the composite in 14 min under an applied voltage of 5 V at -28 degrees C. The excellent performance of WKF/NiCo2S4/rGO/PES composites shows great potential for aerospace structural applications requiring outstanding mechanical properties and Joule heating capability for deicing of surfaces.</P>

Microwave absorption and mechanical performance of α-MnO₂ nanostructures grown on woven Kevlar fiber/reduced graphene oxide-polyaniline nanofiber array-reinforced polyester resin composites

Hazarika, Ankita,Deka, Biplab K.,Kong, Kyungil,Kim, DoYoung,Nam, Young-Woo,Choi, Jae-Hun,Kim, Chun-Gon,Park, Young-Bin,Park, Hyung Wook Elsevier 2018 Composites Part B, Engineering Vol.140 No.-

<P><B>Abstract</B></P> <P>Various morphologies of α-MnO<SUB>2</SUB> nanostructures were synthesized on the surface of woven Kevlar fiber (WKF) by hydrothermal method under different reaction conditions. Reduced graphene oxide-polyaniline nanofiber (RGO-PANI) arrays were synthesized by an <I>in situ</I> dilute polymerization technique and then dispersed within polyester (PES) resin. High-performance composites based on α-MnO<SUB>2</SUB>-grown WKF and RGO-PANI array-dispersed PES were fabricated with effective microwave-absorbing and mechanical properties by vacuum-assisted resin transfer molding (VARTM). WKF/MnO<SUB>2</SUB> nanofibers/PES/PANI-RGO (2%) composites showed superior electromagnetic parameters in the frequency range of 1–18 GHz. The reflection loss (RL) of WKF/MnO<SUB>2</SUB> nanofibers/PES/PANI-RGO (2.0%) was −36.5 dB at an absorbing frequency of 11.8 GHz, which has not been reported before. A higher tensile strength (160.12%), modulus (104.43%), and absorbed impact energy (207%) were observed for α-MnO<SUB>2</SUB> nanofibers, compared with other morphologies of α-MnO<SUB>2</SUB>-incorporated WKF composites and the properties were enhanced with an increased percentage of PANI-RGO.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We prepared various morphological MnO<SUB>2</SUB>nanostructures on WKF by hydrothermal method. </LI> <LI> Polyaniline nanofiber-RGO was synthesized and dispersed in polyester resin. </LI> <LI> Composites were prepared with MnO<SUB>2</SUB> nanostructures-WKF and PANI-RGO/PES by VARTM. </LI> <LI> The composites showed RL of −36.5 dB at an absorbing frequency of 11.8 GHz. </LI> <LI> Tensile strength increased by 160.12% and impact energy by 207% for the composites. </LI> </UL> </P>

Hypercyclic operator weighted shifts

Munmun Hazarika,S. C. Arora 대한수학회 2004 대한수학회보 Vol.41 No.4

We consider bilateral operator weighted shift T onmathbf{L}^2(mathcal{K}) with weight sequence{A_n}_{n=-infty}^infty of positive invertible diagonaloperators on mathcal{K}. We give a characterization for T tobe hypercyclic, and show that the conditions are far simplified incase T is invertible.

On hyponormality of Toeplitz operators with polynomial and symmetric type symbols

Munmun Hazarika,Ambeswar Phukon 대한수학회 2011 대한수학회보 Vol.48 No.3

In [6], it was shown that hyponormality for Toeplitz operators with polynomial symbols can be reduced to classical Schur's algorithm in function theory. In [6], Zhu has also given the explicit values of the Schur's functions [기호]_0, [기호]_1 and [기호]_2. Here we explicitly evaluate the Schur's function [기호]_3. Using this value we find necessary and sufficient conditions under which the Toeplitz operator T_φ is hyponormal, where φ is a trigonometric polynomial given by φ (z)=[수식] and satisfies the condition [수식]. Finally we illustrate the easy applicability of the derived results with a few examples.