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We report detailed magnetic and magnetotransport properties of single-crystalline GdAgSb2antiferromagnet. The electronic transport properties show metallic behavior along with large, anisotropic, and non-saturating magnetoresistance (MR) in transverse experimental configuration. At 2 K and 9 T, the value of MR reaches as high as ∼1.8×103%. The anisotropic MR along with additional features for applied magnetic field along some specific crystallographic directions reveal the quasi-two-dimensional nature of the Fermi surface of GdAgSb2. Hall resistivity confirms the presence of two types of charge carriers. The high carrier mobilities (∼1.2×104 cm2 V-1 s-1) and nearly-compensated electron and hole-density (∼1019 cm-3) could be responsible for the large transverse MR in GdAgSb2. We have also observed the de Haas-van Alphen oscillations in the magnetization measurements below 7 K. Furthermore, the robust planar Hall effect, which persists up to high temperatures, could indicate the nontrivial nature of the electronic band structure for GdAgSb2.

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LaTe3 is a non-centrosymmetric material with time reversal symmetry, where the charge density wave is hosted by the Te bilayers. Here, we show that LaTe3 hosts a Kramers nodal line-a twofold degenerate nodal line connecting time reversal-invariant momenta. We use angle-resolved photoemission spectroscopy, density functional theory with an experimentally reported modulated structure, effective band structures calculated by band unfolding, and symmetry arguments to reveal the Kramers nodal line. Furthermore, calculations confirm that the nodal line imposes gapless crossings between the bilayer-split charge density wave-induced shadow bands and the main bands. In excellent agreement with the calculations, spectroscopic data confirm the presence of the Kramers nodal line and show that the crossings traverse the Fermi level. Furthermore, spinless nodal lines-completely gapped out by spin-orbit coupling-are formed by the linear crossings of the shadow and main bands with a high Fermi velocity.

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Ferroelectric and magnetic properties are investigated for Bi2Fe4O9nanoparticles with different shapes (cuboid and sphere-like) synthesized by hydrothermal and sol-gel method. The magnetic study reveals that coercivity, Neel temperature and remanent magnetization strongly depend on shape of the particle. The nanoparticle with sphere-like shape exhibits magnetization curve of antiferromagnetic (AFM) ordering with ferromagnetic (FM) component. As the particle shape changes from sphere-like to cuboid, the AFM component is dominating over the ferromagnetic component. A small exchange bias is also observed at low temperature in both the sphere-like and cuboid nanoparticle. The coercivity, remanent magnetization and Neel temperature of sphere-like nanoparticle is greater than cuboid nanoparticle. Ferroelectric measurement shows the remanent polarization of cuboid is greater than sphere-like nanoparticle but the coercivity is almost same. This Bi2Fe4O9nanoparticle shows a small change in polarization under magnetic field. The polarization value decreases with magnetic field increases. The magnetoelectric coupling-measured by change of remanent polarization under magnetic field are found to be greater in Bi2Fe4O9sphere-like nanoparticles. These shape dependent magnetic and ferroelectric properties are coming because of shape anisotropy.

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We have studied the effect of doping of both magnetic (Co) and nonmagnetic (Mg) ions at the Cu site on phase transition in polycrystalline α-Cu2V2O7through structural, magnetic, and electrical measurements. X-ray diffraction reveals that Mg doping triggers an onset ofα- toß-phase structural transition in Cu2-xMgxV2O7above a critical Mg concentrationxc= 0.15, and both the phases coexist up tox= 0.25. Cu2V2O7possesses a non-centrosymmetric crystal structure and antiferromagnetic ordering along with a non-collinear spin structure in theαphase, originated from the microscopic Dzyaloshinskii-Moriya interaction between the neighboring Cu spins. Accordingly, a weak ferromagnetic (FM) behavior has been observed up tox= 0.25. However, beyond this concentration, Cu2-xMgxV2O7exhibits complex magnetic properties. A clear dielectric anomaly is observed in α-Cu2-xMgxV2O7around the magnetic transition temperature, which loses its prominence with the increase in Mg doping. The analysis of experimental data shows that the magnetoelectric coupling is nonlinear, which is in agreement with the Landau theory of continuous phase transitions. Co doping, on the other hand, initiates a sharpαtoßphase transition around the same critical concentrationxc= 0.15 in Cu2-xCoxV2O7but the FM behavior is very weak and can be detected only up tox= 0.10. We have drawn the magnetic phase diagram which indicates that the rate of suppression in transition temperature is the same for both types of doping, magnetic (Co) and nonmagnetic (Zn/Mg).

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BACKGROUND: Oral Squamous Cell Carcinoma (OSCC) results from a series of genetic alteration in squamous cells. This particular type of cancer considers one of the most aggressive malignancies to control because of its frequent local invasions to the regional lymph node. Although several biomarkers have been reported, the key marker used to predict the behavior of the disease is largely unknown. Here we report Long INterpersed Element-1 (LINE1 or L1) retrotransposon activity in post-operative oral cancer samples. L1 is the only active retrotransposon occupying around 17% of the human genome with an estimated 500,000 copies. An active L1 encodes two proteins (L1ORF1p and L1ORF2p); both of which are critical in the process of retrotransposition. Several studies report that the L1 retrotransposon is highly active in many cancers. L1 activity is generally determined by assaying L1ORF1p because of its high expression and availability of the antibody. However, due to its lower expression and unavailability of a robust antibody, detection of L1ORF2p has been limited. L1ORF2p is the crucial protein in the process of retrotransposition as it provides endonuclease and reverse transcriptase (RT) activity. METHODS: Immunohistochemistry and Western blotting were performed on the post-operative oral cancer samples and murine tissues. RESULTS: Using in house novel antibodies against both the L1 proteins (L1ORF1p and L1ORF2p), we found L1 retrotransposon is extremely active in post-operative oral cancer tissues. Here, we report a novel human L1ORF2p antibody generated using an 80-amino-acid stretch from the RT domain, which is highly conserved among different species. The antibody detects significant L1ORF2p expression in human oral squamous cell carcinoma (OSCC) samples and murine germ tissues. CONCLUSIONS: We report exceptionally high L1ORF1p and L1ORF2p expression in post-operative oral cancer samples. The novel L1ORF2p antibody reported in this study will serve as a useful tool to understand why L1 activity is deregulated in OSCC and how it contributes to the progression of this particular cancer. Cross-species reactivity of L1ORF2p antibody due to the conserved epitope will be useful to study the retrotransposon biology in mice and rat germ tissues.

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LINEs are retrotransposable elements found in diverse organisms. Their activity is kept in check by several mechanisms, including transcriptional silencing. Here we have analyzed the transcription status of LINE1 copies in the early-branching parasitic protist Entamoeba histolytica. Full-length EhLINE1 encodes ORF1, and ORF2 with reverse transcriptase (RT) and endonuclease (EN) domains. RNA-Seq analysis of EhLINE1 copies (both truncated and full-length) showed unique features. Firstly, although 20/41 transcribed copies were full-length, we failed to detect any full-length transcripts. Rather, sense-strand transcripts mapped to the functional domains- ORF1, RT and EN. Secondly, there was strong antisense transcription specifically from RT domain. No antisense transcripts were seen from ORF1. Antisense RT transcripts did not encode known functional peptides. They could possibly be involved in attenuating translation of RT domain, as we failed to detect ORF2p, whereas ORF1p was detectable. Lack of full-length transcripts and strong antisense RT expression may serve to limit EhLINE1 retrotransposition.

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Oral squamous cell carcinoma (OSCC) is highly predominant in India due to excessive use of tobacco. Here we investigated Long INterpersed Element 1 (LINE or L1) retrotransposon activity in OSCC samples in the same population. There are almost 500,000 copies of L1 occupied around 30%  of the human genome. Although most of them are inactive, around 150-200 copies are actively jumping in a human genome. L1 encodes two proteins designated as ORF1p and ORF2p and expression of both proteins are critical for the process of retrotransposition. Here we have analyzed L1 ORF1p expression in a small cohort (n = 15) of paired cancer-normal tissues obtained from operated oral cancer patients. Immunohistochemistry (IHC) with the human ORF1 antibody showed the presence of ORF1p in almost 60%  cancer samples, and few of them also showed aberrant p53 expression.  Investigating L1 promoter methylation status, showed certain trends towards hypomethylation of the L1 promoter in cancer tissues compared to its normal counterpart. Our data raise the possibility that L1ORF1p expression might have some role in the onset and progression of this particular type of cancer.

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We have investigated the nature of magnetic ground state of RCrTiO5 (R = Dy and Ho) through dc magnetization and heat capacity measurements. Due to the strong competition between the Cr3+ and R 3+ sublattice moments, several intriguing phenomena have been observed when the magnetic state is probed at low field. In both the systems, the Cr3+ sublattice undergoes a long-range antiferromagnetic ordering below ∼139 K with a weak ferromagnetic (FM) moment perpendicular to c axis as evident from the hysteresis in M(H) curve. At low fields ([Formula: see text]150 Oe), the zero-field-cooled magnetization shows that the FM component of Cr3+ spin and R 3+ moments align in the opposite direction with respect to each other and the net moment aligns in the opposite direction to the applied field in the temperature range 136-16 K for DyCrTiO5 and below 128 K for HoCrTiO5. For both the samples, the strong coupling between the two magnetic sublattices is manifested in the temperature dependence of coercive field. Another interesting phenomenon, the spin reorientation transition, has been observed below [Formula: see text] K, where the easy axis of FM moment of Cr3+ starts to rotate from one crystallographic axis toward another in DyCrTiO5 but no such transition has been observed in HoCrTiO5. The other members of RCrTiO5 series do not show such kinds of interesting magnetic properties.

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ZrSiS was recently shown to be a new material with topologically non-trivial band structure that exhibits multiple Dirac nodes and a robust linear band dispersion up to an unusually high energy of 2 eV. Such a robust linear dispersion makes the topological properties of ZrSiS insensitive to perturbations like carrier doping or lattice distortion. Here, we show that a novel superconducting phase with a remarkably high [Formula: see text] of 7.5 K can be induced in single crystals of ZrSiS by a non-superconducting metallic tip of Ag. From first-principles calculations, we show that the observed superconducting phase might originate from a dramatic enhancement of density of states due to the presence of a metallic tip on ZrSiS. Our calculations also show that the emerging tip-induced superconducting phase co-exists with the well preserved topological properties of ZrSiS.

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The physical systems with ferromagnetism and 'bad' metallicity hosting unusual transport properties are playgrounds of novel quantum phenomena. Recently EuTi1-x Nb x O3 emerged as a ferromagnetic system where non-trivial temperature dependent transport properties are observed due to coexistence and competition of various magnetic and non-magnetic scattering processes. In the ferromagnetic state, the resistivity shows a T 2 temperature dependence possibly due to electron-magnon scattering and above the Curie temperature [Formula: see text], the dependence changes to T 3/2 behaviour indicating a correlation between transport and magnetic properties. In this paper, we show that the transport spin-polarization ([Formula: see text]) in EuTi1-x Nb x O3, a low Curie temperature ferromagnet, is as high (∼40%) as that in some of the metallic ferromagnets with high Curie temperatures. In addition, owing to the low Curie temperature of EuTi1-x Nb x O3, the temperature (T) dependence of [Formula: see text] could be measured systematically up to [Formula: see text] which revealed a proportionate relationship with magnetization [Formula: see text] versus T. This indicates that such proportionality is far more universally valid than the ferromagnets with ideal parabolic bands. Furthermore, our band structure calculations not only helped to understand the origin of such high spin polarization in EuTi1-x Nb x O3 but also provided a route to estimate the Hubbard U parameter in complex metallic ferromagnets in general using experimental inputs.

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Magnetization, magnetostriction and dielectric constant measurements are performed on single crystals of quasi-one-dimensional Ising spin chain CoNb2O6 at temperatures below and above the antiferromagnetic phase transition. Field-induced magnetic transitions are clearly reflected in magnetodielectric and magnetostriction data. Sharp anomalies are observed around the critical fields of antiferromagnetic to ferrimagnetic and ferrimagnetic to saturated-paramagnetic transition in both magnetodielectric and magnetostriction experiments. Detailed analysis of temperature and field dependence of dielectric constant and magnetostriction suggests that spins are coupled with lattice as well as charges in CoNb2O6. Below the antiferromagnetic transition temperature, the overall resemblance in anomalies, observed in various physical parameters such as magnetization, dielectric constant, magnetostriction and magnetic entropy change gives a deeper insight about the influence of spin configuration on these parameters in CoNb2O6.

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Municipal wastewater treatment plants (WWTP) have been cited as the reservoirs of antibiotic resistance, as they provide suitable conditions for the selection of antibiotic resistant bacteria over the antibiotic-sensitive ones. This study is an attempt to investigate the occurrence of fluoroquinolone (FQ) antibiotics, FQ-resistant bacteria in a WWTP located in India. The results indicated that the concentrations of FQ resistant bacteria ranged from 5.10 × 103 to 5.76 × 103 CFU/mL in the influent stream and 2.66 × 102 to 4 × 102 CFU/mL in the effluent stream. An increase in the fraction of FQ resistant bacteria over the total bacteria is observed at the bio-outlet indicating there is a selection pressure within the biological treatment unit of the treatment plant. The mean concentrations of the FQ antibiotics, namely ciprofloxacin, norfloxacin and ofloxacin in the influent ranged from 6 to 16.4 µg/L with 60-90% of removal in the biological treatment unit. Chlorine-based disinfection process was able to eliminate 96% of the FQ-resistant bacteria from the treated water being discharged into the river Ganges. However, the risk of horizontal gene transformation of resistance was found to be negligible as the resistant mutations occurred at Quinolone resistant determining region (QRDR) of Gyrase A gene. It is observed that 75% of the isolated bacteria showed two point mutations at S83L and D87N positions of the QRDR region of gyrA gene.

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TaSb2 has been predicted theoretically to be a weak topological insulator. Whereas, the earlier magnetotransport experiment has established it as a topological semimetal. In the previous works, the Shubnikov-de Haas oscillation has been analyzed to probe the Fermi surface, with magnetic field along a particular crystallographic axis only. By employing a sample rotator, we reveal highly anisotropic transverse magnetoresistance by rotating the magnetic field along different crystallographic directions. To probe the anisotropy in the Fermi surface, we have performed magnetization measurements and detected strong de Haas-van Alphen (dHvA) oscillations for the magnetic field applied along a and b axes as well as perpendicular to ab plane of the crystals. Three Fermi pockets have been identified by analyzing the dHvA oscillations. With the application of magnetic field along different crystal directions, the cross-sectional areas of the Fermi pockets have been found significantly different, i.e., the Fermi pockets are highly anisotropic in nature. Three-band fitting of electrical and Hall conductivity reveals two high mobility electron pockets and one low mobility hole pocket. The angular variation of transverse magnetoresistance has been qualitatively explained using the results of dHvA oscillations and three-band analysis.

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BACKGROUND: Recent reports indicate that retrotransposons - a type of mobile DNA - can contribute to neuronal genetic diversity in mammals. Retrotransposons are genetic elements that mobilize via an RNA intermediate by a "copy-and-paste" mechanism termed retrotransposition. Long Interspersed Element-1 (LINE-1 or L1) is the only active autonomous retrotransposon in humans and its activity is responsible for ~ 30% of genomic mass. Historically, L1 retrotransposition was thought to be restricted to the germline; however, new data indicate L1 s are active in somatic tissue with certain regions of the brain being highly permissive. The functional implications of L1 insertional activity in the brain and how host cells regulate it are incomplete. While deep sequencing and qPCR analysis have shown that L1 copy number is much higher in certain parts of the human brain, direct in vivo studies regarding detection of L1-encoded proteins is lacking due to ineffective reagents. RESULTS: Using a polyclonal antibody we generated against the RNA-binding (RRM) domain of L1 ORF1p, we observe widespread ORF1p expression in post-mortem human brain samples including the hippocampus which has known elevated rates of retrotransposition. In addition, we find that two brains from different individuals of different ages display very different expression of ORF1p, especially in the frontal cortex. CONCLUSIONS: We hypothesize that discordance of ORF1p expression in parts of the brain reported to display elevated levels of retrotransposition may suggest the existence of factors mediating post-translational regulation of L1 activity in the human brain. Furthermore, this antibody reagent will be useful as a complementary means to confirm findings related to retrotransposon biology and activity in the brain and other tissues in vivo.

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We report semiconductor to metal-like crossover in the temperature dependence of resistivity (ρ) due to the switching of charge transport from bulk to surface channel in three-dimensional topological insulator Bi1.5Sb0.5Te1.7Se1.3. Unlike earlier studies, a much sharper drop in ρ(T) is observed below the crossover temperature due to the dominant surface conduction. Remarkably, the resistivity of the conducting surface channel follows a rarely observable T 2 dependence at low temperature, as predicted theoretically for a two-dimensional Fermi liquid system. The field dependence of magnetization shows a cusp-like paramagnetic peak in the susceptibility (χ) at zero field over the diamagnetic background. The peak is found to be robust against temperature and χ decays linearly with the field from its zero-field value. This unique behavior of the χ is associated with the spin-momentum locked topological surface state in Bi1.5Sb0.5Te1.7Se1.3. The reconstruction of the surface state with time is clearly reflected through the reduction of the peak height with the age of the sample.

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Novel topological state of matter is one of the rapidly growing fields in condensed matter physics research in recent times. While these materials are fascinating from the aspect of fundamental physics of relativistic particles, their exotic transport properties are equally compelling due to the potential technological applications. Extreme magnetoresistance and ultrahigh carrier mobility are two such major hallmarks of topological materials and often used as primary criteria for identifying new compounds belonging to this class. Recently, LaBi has emerged as a new system, which exhibits the above mentioned properties. However, the topological nature of its band structure remains unresolved. Here, using the magnetotransport and magnetization measurements, we have probed the bulk and surface states of LaBi. Similar to earlier reports, extremely large magnetoresistance and high carrier mobility have been observed with compensated electron and hole density. The Fermi surface properties have been analyzed from both Shubnikov-de Haas and de Haas-van Alphen oscillation techniques. In the magnetization measurement, a prominent paramagnetic singularity has been observed, which demonstrates the non-trivial nature of the surface states in LaBi. Our study unambiguously confirms that LaBi is a three-dimensional topological insulator with possible linear dispersion in the gapped bulk band structure.

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Whereas the discovery of Dirac- and Weyl-type excitations in electronic systems is a major breakthrough in recent condensed matter physics, finding appropriate materials for fundamental physics and technological applications is an experimental challenge. In all of the reported materials, linear dispersion survives only up to a few hundred millielectronvolts from the Dirac or Weyl nodes. On the other hand, real materials are subject to uncontrolled doping during preparation and thermal effect near room temperature can hinder the rich physics. In ZrSiS, angle-resolved photoemission spectroscopy measurements have shown an unusually robust linear dispersion (up to [Formula: see text]2 eV) with multiple nondegenerate Dirac nodes. In this context, we present the magnetotransport study on ZrSiS crystal, which represents a large family of materials (WHM with W = Zr, Hf; H = Si, Ge, Sn; M = O, S, Se, Te) with identical band topology. Along with extremely large and nonsaturating magnetoresistance (MR), [Formula: see text]1.4 [Formula: see text] 105% at 2 K and 9 T, it shows strong anisotropy, depending on the direction of the magnetic field. Quantum oscillation and Hall effect measurements have revealed large hole and small electron Fermi pockets. A nontrivial [Formula: see text] Berry phase confirms the Dirac fermionic nature for both types of charge carriers. The long-sought relativistic phenomenon of massless Dirac fermions, known as the Adler-Bell-Jackiw chiral anomaly, has also been observed.

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Although, the long-standing debate on the resistivity anomaly in ZrTe5 somewhat comes to an end, the exact topological nature of the electronic band structure remains elusive till today. Theoretical calculations predicted that bulk ZrTe5 to be either a weak or a strong three-dimensional (3D) topological insulator. However, the angle resolved photoemission spectroscopy and transport measurements clearly demonstrate 3D Dirac cone state with a small mass gap between the valence band and conduction band in the bulk. From the magnetization and magneto-transport measurements on ZrTe5 single crystal, we have detected both the signature of helical spin texture from topological surface state and chiral anomaly associated with the 3D Dirac cone state in the bulk. This implies that ZrTe5 hosts a novel electronic phase of material, having massless Dirac fermionic excitation in its bulk gap state, unlike earlier reported 3D topological insulators. Apart from the band topology, it is also apparent from the resistivity and Hall measurements that the anomalous peak in the resistivity can be shifted to a much lower temperature (T < 2 K) by controlling impurity and defects.

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Almost two-thirds of the human genome is repetitive DNA, mostly derived from different kinds of transposon and retrotransposon sequences. Although most of these sequences are stable in the genome, one class called long interspersed element (LINE1 or L1) is actively jumping in the human genome, particularly in brain, germ cells, and certain types of cancer. Recent estimates predict that L1 activity combined with L1-mediated activity is responsible for a new insertion in 1 out of 25 newborns. In humans, more than 100 single-gene disease cases have been reported due to L1 activity. An active L1 encodes two proteins designated as ORF1p and ORF2p. L1 jumps by a target primed reverse transcription (TPRT) mechanism where L1 RNA forms L1-RNPs after binding with L1 proteins. L1-RNPs then enter into the nucleus where L1 RNA is converted to cDNA at the site of integration which subsequently integrates into the genome with the help of the L1 proteins (ORF1p and ORF2p) and other cellular factors. Although L1 is continuously jumping in the human genome the basic mechanism and requirement of other cellular factors in L1 retrotransposition are relatively unknown due to the difficulty in purifying intact L1-RNPs. Here we describe a detailed protocol for purification of L1-RNPs by an immunoaffinity method.

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This study was designed to investigate the effects of turmeric powder and processed sulphur on the weight gain, body fat deposition and lipid profile of serum and liver in Wistar rats. Twenty-five rats of 6 weeks old were divided into five groups with 5 rats in each group. Each group was fed different diets as follows I. common diet (CON); II. high fat diet (HFD); III. 10% turmeric powder with HFD (T); IV. 10% turmeric powder and 0.19% processed sulphur with HFD (TS); and V. 0.38% processed sulphur with HFD (S). The experimental feeding was continued for 6 weeks. The body weight gain and feed efficiency ratio (FER) in the T and TS group rats were significantly (p < 0.05) lower than that of the HFD group rats. The retroperitoneal fat weights in the rats belong to T, TS and S groups were lower than that of the HFD group rats and the TS group had significant (p < 0.05) reduction in retroperitoneal fat compared to the HFD group rats. The epididymal fat weights in rats of the T, TS and S groups also showed a lowering tendency compared to that of the HFD group rats. The hepatic total lipid levels in the T and TS group rats were significantly (p < 0.05) lower than that of the HFD group rats. The hepatic triglyceride level in the rats of TS group was significantly (p < 0.05) lower than that of the HFD group rats. The serum total cholesterol, high-density lipoprotein (HDL) and low density lipoprotein (LDL) associated cholesterol contents in rats of the T and TS group were significantly (p < 0.05) higher than that of the HFD group rats, however, there was no significant difference in serum triglyceride. The results suggest that turmeric powder along with sulphur can reduce the weight gain, body fat deposition and improve serum and liver lipid profile in rats fed with a high fat diet.