Transition metal titanium (Ti) doped LaFeO3 nanoparticles for enhanced optical structural and magnetic properties

A series of LaFe1−xTixO3 (x = 0.0, 0.2, 0.4, 0.6 and 0.8) nanoparticles have been successfully synthesized by simple co-precipitation technique. The synthesized samples (calcined at 800° C/3hr) were characterised for structural, optical and magnetic properties. Structural phase formation of the crystal shows orthorhombic planes of these samples phases. The average crystallite size (Dc) is decreasing with a dopant and found to be varying between ∼ 9 and 25 nm. Tailored surface morphology was analyzed using scanning electron microscope (FESEM) and transmission electron microscopes (TEM) with selected area electron diffraction pattern (SAED) also confirms the evolution of orthorhombic phases. Diffuse reflectance spectra (DRS) are recorded to evaluate the variation of optical band gap (Eg) upon titanium doping into the LaFeO3 system. The obtained results attributed that Eg values are increasing with dopant altering between 2.05 and 2.61 eV. The metal oxide (M - O) stretching vibrations and few functional groups are detected from infrared spectra (IR). The weak ferromagnetic behaviour is observed from hysteresis loop behaviour. Additionally, the large hysteresis loop behaviour induces no saturation up to 15 kOe in nanoparticles coercivity (Hc) and anisotropy constants (K1) are eventually decreasing with ‘x’ values

Colossal Magnetoresistance by Avoiding a Ferromagnetic State in the Mott System Ca3Ru2O7

Transport and magnetic studies of Ca3Ru2O7 for temperatures ranging from 0.4 K to 56 K and magnetic fields, B, up to 45 T leads to strikingly different behavior when the field is applied along the different crystal axes. A ferromagnetic (FM) state with full spin polarization is achieved for B||a-axis, but colossal magnetoresistance is realized only for B||b-axis. For B||c-axis, Shubnikov-de Haas oscillations are observed and followed by a less resistive state than for B||a. Hence, in contrast to standard colossal magnetoresistive materials, the FM phase is the least favorable for electron hopping. These properties together with highly unusual spin-charge-lattice coupling near the Mott transition (48 K) are driven by the orbital degrees of freedom.Comment: 15 pages including 3 figure

High-temperature weak ferromagnetism on the verge of a metallic state: Impact of dilute Sr-doping on BaIrO3

The 5d-electron based BaIrO3 is a nonmetallic weak ferromagnet with a Curie temperature at Tc=175 K. Its largely extended orbitals generate strong electron-lattice coupling, and magnetism and electronic structure are thus critically linked to the lattice degree of freedom. Here we report results of our transport and magnetic study on slightly Sr doped BaIrO3. It is found that dilute Sr-doping drastically suppresses Tc, and instantaneously leads to a nonmetal-metal transition at high temperatures. All results highlight the instability of the ground state and the subtle relation between magnetic ordering and electron mobility. It is clear that BaIrO3 along with very few other systems represents a class of materials where the magnetic and transport properties can effectively be tuned by slight alterations in lattice parameters

Parasitoid complex of legume pod borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae) on different pulses

The spotted pod borer, Maruca vitrata Fabricius is an important herbivore of major pulses and vegetable legumes in India and the chemical pesticides are major contributors for its management. In order to have an idea on other alternative management tools, the present studies were carried out on the availability of parasitoids and its genetic variation. Totally, four larval parasitoids viz., Bassus sp., Trathala flavoorbitalis Cameron, Phanerotoma hendecasisella Cameron and an undetermined Braconid wasp were recorded on M. vitrata larva. The occurrence of P. hendecasisella was reported for the first time from Tamil Nadu, India. The Bassus sp. was found to be dominant with the parasitism of 3.0 to 12.7% in different pulses and total parasitism of four parasitoids was maximum in pigeonpea (16.1 %). Total parasitism had a positive relationship with number of webbings on cowpea. The larval parasitoids Bassus sp. and braconid wasp (undetermined) yielded specific fragments (~800 bp) with mitochondrial COI primer. Presence of Wolbachia was confirmed in all four larval parasitoids with the amplicons size between 600 and 650 bp. Present study clearly indicated the close proximity of Bassus sp. on M. vitrata than other parasitoids studied. Hence, it gives way for further insights on suitability, mass culturing and development for sustainable management of this insect pest

EERP: Intelligent Cluster based Energy Enhanced Routing Protocol Design over Wireless Sensor Network Environment

Wireless Sensor Network (WSN)) and the associated technologies are growing day-by-day in a drastic level. The Wireless Sensor Network medium has a distributed communication logic, in which it is interconnected with set of wireless sensor nodes and a unique basestation. A basestation stays in a constant place to provide a support to the transceivers for achieving a successful communication between source and destination entities. This kind of wireless communication mediums highly depends on the basestation to acquire the transaction needs as well as the basestation acts as a gateway between transmitter and receiver units. The cluster based wireless communication models are introduced to provide a flaw free communication between entities on WSN region with handling of wireless sensor nodes in the form of cluster. In literature several cluster enabled wireless communication models are designed, but all are strucked up with improper node placements and associated energy level mismatching. These issues raise cost efficient problems in Wireless Sensor Network environment. SO, that a new energy efficient routing protocol with an effective communication strategy is required to solve such issues in past. This paper introduced a new routing protocol with high efficient data transmission norms, in which it is called as Energy Enhanced Routing Protocol (eeRP). The proposed approach of eeRP associates the powerful clustering logic in this scheme to provide a fault free communication model to the WSN environment. By using this approach the standardized routing model is constructed with respect to the sensor nodes and basestation. The most important part of cluster based wireless communication model is the handling of Cluster-Head (CH), in which it needs to be elected based on certain communication principles such as the estimation of distance, position of other nodes in the cluster region, basestation positioning and the node capability. These constraints are essential to analyze the Cluster-Head to improve the pathway estimation process. The proposed approach of eeRP utilizes the powerful CH election algorithm called Firefly to provide an intellectual cluster head election process. The performance level of the proposed approach eeRP is estimated based on the efficiency of throughput, path selection efficiency, reduced energy consumption ratio and the network lifetime improvement. The experimental results assure these metrics in resulting section with graphical proofs

Borderline magnetism in Sr4Ru3O10: Impact of dilute La and Ca doping on itinerant ferromagnetism and metamagnetism

An investigation of La and Ca doped Sr4Ru3O10, featuring a coexistence of interlayer ferromagnetism and intralayer metamagnetism, is presented. La doping readily changes magnetism between ferromagnetism and metamagnetism by tuning the density of states. It also results in different Curie temperatures for the c-axis and the basal plane, highlighting a rare spin-orbit coupling with the crystal field states. In contrast, Ca doping enhances the c-axis ferromagnetism and the magnetic anisotropy. La doping also induces a dimensional crossover in the interlayer transport whereas Ca doping exhibits a tunneling magnetoresistance and an extraordinary T3/2-dependence of the resisitivity. The drastic changes caused by the dilute doping demonstrate a rare borderline magnetism that is delicately linked to the interplay of the density of states and spin-orbit coupling.Comment: 5 figure

LEFTY2 inhibits endometrial receptivity by downregulating Orai1 expression and store-operated Ca²+ entry

Early embryo development and endometrial differentiation are initially independent processes, and synchronization, imposed by a limited window of implantation, is critical for reproductive success. A putative negative regulator of endometrial receptivity is LEFTY2, a member of the transforming growth factor (TGF)-β family. LEFTY2 is highly expressed in decidualizing human endometrial stromal cells (HESCs) during the late luteal phase of the menstrual cycle, coinciding with the closure of the window of implantation. Here, we show that flushing of the uterine lumen in mice with recombinant LEFTY2 inhibits the expression of key receptivity genes, including Cox2, Bmp2, and Wnt4, and blocks embryo implantation. In Ishikawa cells, a human endometrial epithelial cell line, LEFTY2 downregulated the expression of calcium release-activated calcium channel protein 1, encoded by ORAI1, and inhibited store-operated Ca2+ entry (SOCE). Furthermore, LEFTY2 and the Orai1 blockers 2-APB, MRS-1845, as well as YM-58483, inhibited, whereas the Ca2+ ionophore, ionomycin, strongly upregulated COX2, BMP2 and WNT4 expression in decidualizing HESCs. These findings suggest that LEFTY2 closes the implantation window, at least in part, by downregulating Orai1, which in turn limits SOCE and antagonizes expression of Ca2+-sensitive receptivity genes

Prediction of length of stay for stroke patients using artificial neural networks

Strokes are neurological events that affect a certain area of the brain. Since brain controls fundamental body activities, brain cell deterioration and dead can lead to serious disabilities and poor life quality. This makes strokes the leading cause of disabilities and mortality worldwide. Patients that suffer strokes are hospitalized in order to be submitted to surgery and receive recovery therapies. Thus, it’s important to predict the length of stay for these patients, since it can be costly to them and their family, as well as to the medical institutions. The aim of this study is to make a prediction on the number of days of patients’ hospital stays based on information available about the neurological event that happened, the patient’s health status and surgery details. A neural network was put to test with three attribute subsets with different sizes. The best result was obtained with the subset with fewer features obtaining a RMSE and a MAE of 5.9451 and 4.6354, respectively.FCT - Fundação para a Ciência e a Tecnologia (UID/CEC/00319/2019