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Multi-path and multi-hop routing are multi-objective optimization problems involving multiple constraints that need to be addressed in the current scenario in wireless sensor networks. The routing process is challenging due to the constrained energy resources and transmission bandwidth. The conventional strategies possess shortcomings, like, as high computing complexity, extensive problem-solving time, complexity in achieving optimal values, and ease of falling into local solutions. Hence, the aim is to propose a hybrid metaheuristic algorithm, known as a multi-objective optimized multi-path and multi-hop routing algorithm (MMMRA). It incorporates the chimp optimization algorithm (COA) for determining the optimal multi-path route based on multi-objective function and ant colony optimization for determining the optimal multi-hop routing. The proposed MMMRA is implemented using NS-2 and to evaluate the performance, nine various scenarios are considered. The MMMRA is validated using different performance measures and compared with other benchmark algorithms. The simulation results indicate that the MMMRA exhibits percentage improvement in terms of residual energy by 1.63%, 4.96%, 6.89%, 7.51%, and 9.67% over IPSMT, BIM2RT, SCP, PSOBS, and RDICMR algorithms respectively. Moreover, the HND and FND of the MMMRA algorithm perform better in all three scenarios (center, corner, and outside positions of sink node), especially when the sink node is placed at the center position, the HND of MMRA shows a percentage improvement by 24% and 12.73% over IPSO–GWO, and COA–HGS algorithms respectively. Similarly, the FND of MMRA shows percentage improvement by 21.05% and 9.5% over IPSO–GWO, and COA–HGS algorithms respectively. [ABSTRACT FROM AUTHOR]

We theoretically explore optical bistability/multistability and transmission spectrum in a hybrid optomechanical system consisting of quantum dot molecules in a semiconductor cavity which is in turn coupled to an auxiliary cavity. This auxiliary cavity exhibits both linear and quadratic couplings to a mechanical oscillator. Here, the hybrid optomechanical system is continuously driven by a strong laser from both ends and a weak probe field applied to an auxiliary cavity. The nonlinear nature of the system in the Heisenberg-Langevin equation is taken into consideration and the perturbation method is utilized to deal with problems in the continuous wave regime. The outcome reveals that optical multistability and transmission (absorption and dispersion) spectrum can be deftly manipulated by properly adjusting the parameters. Such an investigation may be useful in designing all-optical switching devices. [ABSTRACT FROM AUTHOR]

We investigate theoretically, the optical response for a cavity optomechanical system containing a Kerr non-linear substrate. The optomechanical cavity's moving membrane interacts linearly and quadratically with the radiation pressure of the photons. We found that the quadratic non-linear coupling and Kerr non-linearity strongly influence the system's optical multistability. Further, the transmission spectrum is observed under the influence of both non-linearities. Our theoretical results show that the width of the spectrum alters significantly by tuning the non-linearities present in the system. In addition, our results show that a peculiar positive value of quadratic optomechanical coupling is instrumental in generating Normal Mode splitting while the absence and negative value of quadratic optomechanical coupling inhibit the Normal-Mode splitting. [ABSTRACT FROM AUTHOR]

In this article, we study the spin and tunneling dynamics as a function of magnetic field in a one-dimensional GaAs double quantum dot with both the Dresselhaus and Rashba spin-orbit coupling. In particular, we consider different spatial widths for the spin-up and spin-down electronic states. We find that the spin dynamics is a superposition of slow as well as fast Rabi oscillations. It is found that the Rashba interaction strength as well as the external magnetic field strongly modifies the slow Rabi oscillations which is particularly useful for implementing solid state selective spin transport device. [ABSTRACT FROM AUTHOR]

Background: Patients with low ejection fraction undergoing lower abdominal surgeries often require careful management of anesthesia to minimize cardiovascular risks. Epidural anesthesia with local anesthetics such as levobupivacaine or ropivacaine combined with dexmedetomidine has been shown to provide effective analgesia and hemodynamic stability. However, the comparative effects of these two agents in this patient population remain unclear. Materials and methods: A prospective, randomized study was conducted on 100 patients with low ejection fraction undergoing lower abdominal surgeries. Patients were randomly allocated into two groups: one receiving epidural levobupivacaine plus dexmedetomidine (Group L) and the other receiving epidural ropivacaine plus dexmedetomidine (Group R). Hemodynamic parameters, intraoperative and postoperative analgesic requirements, postoperative pain scores, time to first analgesic request, onset of drug action, and adverse events were recorded and compared between the two groups. Results: In Group L, intraoperative mean arterial pressure (MAP) was maintained within 20% of baseline values more effectively compared to Group R (p < 0.05). Additionally, patients in Group L required significantly lower intraoperative and postoperative opioid consumption (p < 0.05). Postoperative pain scores were also lower in Group L compared to Group R at various time points (p < 0.05). Time to first analgesic request was significantly longer in Group L compared to Group R (p < 0.05). Levobupivacaine demonstrated a faster onset of action compared to ropivacaine (p < 0.05). Both groups exhibited comparable rates of adverse events. Conclusion: Epidural levobupivacaine plus dexmedetomidine provides superior hemodynamic stability, reduced intraoperative and postoperative opioid consumption, better pain control, faster onset of action, and prolonged time to first analgesic request compared to epidural ropivacaine plus dexmedetomidine in patients with low ejection fraction undergoing lower abdominal surgeries. Thus, levobupivacaine may be a preferable choice for epidural anesthesia in this patient population. [ABSTRACT FROM AUTHOR]

We theoretically investigate optical bistability/multistability for all optical switching signature in a hybrid semiconductor microcavity system comprising a quantum well and a Kerr nonlinear substrate. The system is essentially two optically coupled microcavities with one of the microcavity being driven by an external amplitude-modulated pump laser. We show that the switching between bistable and multistable behaviour is influenced by the modulated pump laser, Kerr nonlinearity and the optical coupling between the two microcavities. We further investigate the intracavity spectrum of quantum fluctuations which exhibit the well-known normal mode splitting (NMS). The NMS behaviour is also found to be influenced by the system parameters. These results demonstrate that the present hybrid nonlinear system can be used in designing sensitive optical devices. [ABSTRACT FROM AUTHOR]

We propose a scheme to implement a strong photon blockade with two interacting quantum dots, optically coupled to a semiconductor microcavity. The photon blockade effect is enhanced by simultaneously driving the microcavity and one of the two quantum dots with two classical laser fields. Quantum interference effect with different transition paths is the mechanism responsible with photon blockade. This system has been found to be a tunable source of single or two-photon with applications in solid state quantum computation and quantum information processing. [ABSTRACT FROM AUTHOR]

Abstract The fast charge and discharge capability of lithium-ion batteries is improved by applying a lamination step during cell assembly. Electrode sheets and separator are laminated into one stack which improves the electrochemical performance as well as the stack assembly process. The effect of non-laminated and laminated interfaces on the reversible capacity during cycling are studied thoroughly in half-cell and full-cell configurations. The fully-laminated cells show a reduction in the capacity losses of 3%, 5% and 12% upon cycling at 2C, 3C and 5C-rate, respectively, while capacity losses of 6%, 11% and 23% are observed in non-laminated cells at the same C-rates. A significant reduction in the capacity fading at high C-rates is observed upon lamination. Additional compression is applied on the cells to compare the effect of lamination and compression on the cell performance. The laminated cells show an improvement in the fast charging capability in comparison to the non-laminated cells. [ABSTRACT FROM AUTHOR]

Abstract The mechanical, structural and ionic conductivity properties of the polymeric composite membranes are elucidated here according to the weight% amount of inorganic additives. 3 M PFSA (perfluorosulfonic acid) polymer, borosilicate glass particles coated with nanoparticles and sulfuric acid (H 2 SO 4) as functionalized solid inorganic additives (FSIA) are used to improve the overall properties. Wide–angle X-ray diffraction (WAXS) results elucidated the presence of both non-crystalline and crystalline ordered-disordered hydrophobic regions. In the presence of water, the size of the crystalline domains increased which help to increase the crystallinity. The dynamic mechanical analysis (DMA) results indicate the improved mechanical stability of the polymeric composite membranes and the results are consistent with the suggestions that dynamic cross-links [R-SO 3 H.... (SiO 2)] density is higher in the composite membranes and supports to enhance the properties without compromising ionic conductivity unless the amount of FSIA exceeds 3 weights (wt.) %. The coating of nanoparticles made an excellent interface between FSIA and polymer matrix as observed in SEM analysis and block the movement of other ions such as SiO 2 , Na+, K+ which could also participate in overall ionic conductivity. Moreover, as a result, the mobility of polymer side chains increased in conjunction with water-FSIA-H 2 SO 4 because of strong hydrogen bonding, which help to improve the ionic conductivity of final polymer composite. Graphical abstract fx1 Highlights • 3 wt% FSIA additives helped to improve mechanical strength and crystallinity. • Nano-particles coating helped to make an excellent interphase between FSIA and polymer matrix. • Surface functionality improves the overall mechanical and ionic properties of PFSA composites. • FSIA helps in prevention of ion-exchange from glass particles to the proton conductive polymer. • FSIA helps to improve overall ionic conductivity at high temperature and low humidity. [ABSTRACT FROM AUTHOR]

The mechanism of a low temperature wet chemical route for synthesis of LiFePO 4 cathode material for Li-ion batteries is presented. Using inorganic salts as precursors and diethylene glycol (DEG) as reaction media, nanosize LiFePO 4 powder is obtained. The controversially discussed role of the polyol on this reaction has been clarified by in-situ FT-IR analysis of the gaseous reaction products and a full analysis of solid products. It is observed that DEG does not act as reducing agent for iron(II) salts, nor is it oxidized during the synthesis of LiFePO 4 . Generally, polyols are used to reduce the oxides and hydroxides into their corresponding metals. The nucleation of Li + , PO 4 3 − and Fe 2 + -ions in the DEG solvent starts at temperatures 110 °C, 130 °C and 170 °C, respectively. LiFePO 4 precipitation from Li-carbonate, Fe(II)-oxalate dihydrate and ammonium dihydrogenphosphate as precursors is driven by thermal decomposition of the salts, intermediate formation and dehydration of amino-ethoxy-ethane, yielding 1,4-dioxane as volatile by-product. With the help of in-situ investigations reaction time and temperature could be minimized. Furthermore, the effect of the concentrations of Li + , Fe 2 + and PO 4 3 − ionic moieties on the morphology of LiFePO 4 materials obtained by chemical solution deposition and solid state reaction are studied with the help of FT-IR analysis. LiFePO 4 platelets morphology exhibited better discharge capacity than LiFePO 4 agglomerate morphology. The solid product is characterized by X-ray diffraction, scanning electron microscopy and differential thermogravimetry combined with mass spectrometry and FT-IR. [ABSTRACT FROM AUTHOR]

Li-ion batteries are commonly used in portable electronic devices due to their outstanding energy and power density. A remaining issue which hinders the breakthrough e.g. in the automotive sector is the high production cost. For low power applications, such as stationary storage, batteries with electrodes thicker than 300 μ m were suggested. High energy densities can be attained with only a few electrode layers which reduces production time and cost. However, mass and charge transport limitations can be severe at already small C-rates due to long transport pathways. In this article we use a detailed 3D micro-structure resolved model to investigate limiting factors for battery performance. The model is parametrized with data from the literature and dedicated experiments and shows good qualitative agreement with experimental discharge curves of thick NMC-graphite Li-ion batteries. The model is used to assess the effect of inhomogeneities in carbon black distribution and gives answers to the possible occurrence of lithium plating during battery charge. Based on our simulations we can predict optimal operation strategies and improved design concepts for future Li-ion batteries employing thick electrodes. [ABSTRACT FROM AUTHOR]

A series of optimized graphite anodes and NMC cathodes with thicknesses from 70 μm to 305 μm were prepared to study the influence of the ratio of active material to inactive substrate foil on the cycle stability and energy density of lithium ion full cells. Cells with electrodes of up to 155 μm thickness showed no capacity losses for C-rates up to C/2 and excellent cycling stability. For thicker electrodes the kinetic losses increased with C-rate and cycle stability deteriorated. However, for a given C-rate and in a realistic cell design, the energy density could be increased by up to 29% compared to the standard thickness. [ABSTRACT FROM AUTHOR]

We theoretically investigate optical bistability/multistability and transmission spectrum in a quadratically coupled optomechanical system consisting of an optical cavity with quantum dot molecules inside it. The optomechanical cavity is driven by a strong pump laser and a weak probe field. We observed that the optical tristability in the presence of quadratic optomechanical coupling transforms into optical bistability in the absence of quadratic optomechanical coupling. We further investigate this hybrid system's absorption and dispersion spectrum by changing the various control parameters like quadratic optomechanical coupling and intensity of strong pump laser field. In addition, we observed the superluminal effect of the transmitted probe field by calculating the group velocity index of light, which is influenced by system parameters. Such results may be useful for designing all-optical switching and novel quantum photonic devices. [ABSTRACT FROM AUTHOR]

Abstract: As a new approach, LiFePO4 nanoparticles were directly synthesized from precursors iron(III) nitrate and lithium dihydrogen phosphate by a polyol process without post heat treatment in one step. The obtained powders were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and combined thermogravimetry and differential scanning calorimetry and mass spectroscopy TG/DSC/MS. The X-ray diffraction showed the orthorhombic crystal structure of LiFePO4 without any impurity phases. The synthesized LiFePO4 has rhombohedral morphology with high aspect ratio with a thickness of less than 100nm. TG/DSC/MS revealed a weight loss of only 10.9 wt.% when heating up to 1000°C. Electrodes prepared from the LiFePO4 particles were electrochemically characterized by cycling at 0.1C current rate and temperatures in half cell measurements against lithium foil between 2 and 4.2V in an EC/DMC electrolyte with 1M LiPF6 as conductive salt. A reversible specific capacity of 146mAh/g was achieved by applying carbon coating on the rhombohedral particles. [Copyright &y& Elsevier]

Abstract: CuAlO2 due to its delafossite structure is known to exhibit p-type conductivity. p-CuAlO2 thin films have been prepared using spray pyrolysis technique. The films prepared using precursor solutions with different pH values have been characterized for optical, structural and morphological properties. The X-ray diffractograms of the films deposited using precursor solution with pH 3.7 do not show any peaks, these suggest the amorphous nature of the films. On the other hand, the films deposited with pH 1.5 show the peaks of CuAlO2 with delafossite crystal structure. Thus the pH of the solution is playing a crucial role in giving the crystalline product of the material of interest. Tauc''s plot of the film deposited using precursor solution of pH 3.7 shows the absorption edge at 3.71 eV and the film deposited with solution pH 1.5 shows the absorption edge at 3.64 eV, corresponding to the direct band gap of CuAlO2. This confirms the formation of CuAlO2. The surface morphology of the films shows the novel networking structure. Compositional analysis done using Energy dispersive X-ray spectrum shows an excess of oxygen that should be favorable for giving the p-characteristics. [Copyright &y& Elsevier]

Activities of the cell‐wall degrading enzymes cellulase (EC 3. 2. 1. 4). poly‐galacturonase (EC 3. 2. 1. 15) and xylanase (EC 3. 2. 1. 8), and also that of protease (EC 3. 4. 21. 14) have been determined in the parasite Orobanche aegyiptiaca Pers. and in the roots of infected and control host plants of Brassica campestris L. var. rapa Hartm. Shoots, roots and root‐freed tubers of Orobanche showed pronounced activities of these enzymes. When expressed in terms of specific activity, protease, cellulase and polygalacturonase activities were higher and xylanase lower in all parts of Orobanche than in the roots of infected or control host plants. Orobanche roots had higher activities of cellulase, polygalacturonase and protease than tuber or shoot. While xylanase activity was higher in the shoot than in roots or tuber. Infection by Orobanche significantly enhanced the cellulase activity of host roots. Cellulase and polygalacturonase in the Orobanche roots appear as the main enzymes involved in establishing haustorial connection with the host root. Protease might be involved in degrading proteins and lipoproteins of the cell walls and membranes of the host tissues. [ABSTRACT FROM AUTHOR]

In a study of host‐parasite interrelationship and the mechanism of parasitization, ribonuclease activity was determined in Cuscuta reflexa Roxb, and in infected and control host plants of Lantana camara L. In the haustoria‐bearing region of Cuscuta, the concave half of the vine bearing the haustorial site, always showed significantly higher RNase activity than the convex half, irrespective of the differing enzyme activity of the parasite tissue growing on different hosts —Brassica campestris L., Helianthus animus L., Lantana camara L., Medicago saliva L. and Solatium nigrum L. The uninfected host branch of L. camara showed the maximum specific RNase activity in the apical region which decreased toward the base, while the infected host branch showed minimum specific RNase activity in the apical region, gradually increasing towards the infected region. [ABSTRACT FROM AUTHOR]

Changes in the contents of starch, protein, DNA, RNA, total phosphorus., acid soluble phosphorus and inorganic phosphorus, and in the activities of some enzymes. of carbohydrate, amino acid, nucleic acid and phosphate metabolism were studied during the germination of Cuscuta campestris seeds. The results are expressed on per seed basis. Starch content in Cuscuta seeds showed: .a steady decline with most of it depleted by the end of the eighth day of germination. Protein content increased with germination up to 48 h and then decreased. RNA and DNA contents increased to a maximal level on the fourth day of germination aid then decreased, Total phosphorus in the seeds remained almost unchanged during the period of study, Both trichioroacetic add soluble and inorganic phosphorus increased until the third day and then decreased. Phytin was rapidly hydrolyzed with little being detectable by the seventh day of germination. Glucose-6-phosphate dehydrogenase increased with germination, while fructose bisphosphate aldolase which is indispensable for glycolysis, decreased with germination. Ribonuclease and ,deoxyribonuclease increased till the third and fourth day, respectively, and then decreased. Aspartate and alanine aminotransferases showed .a maximum on the second day and then decreased. Activities of alkaline fructose-1,6-bisphosphatase and phytase were absent in the dry seeds. and appeared only on the second day of germination. Both α- and β-amylase activities were present in the dry seed. [ABSTRACT FROM AUTHOR]

Metabolic changes in developing Cuscuta campestris Yunck seeds were studied with respect to TCA-soluble phosphate fractions, nucleic acids and the enzymes, viz. acid and alkaline phosphatase, neutral and alkaline FDPase, starch phosphorylase, α-amylase ribonuclease, deoxyribonuclease and phytase. RNA and DNA contents increased steadily, and then remained stationary during the last two stages. The activities of all the enzymes studied increased with development with a sharp fall in the final stage. Interestingly, α-amylase was present throughout the seed development. Phytic acid (16% of the total F) dues not seem to function as phosphate reservoir, instead orthophosphate (13% of the total P) and nucleic acids (30% of the total F) may serve this function. [ABSTRACT FROM AUTHOR]

Cytokinins in the different regions of Cuscuta reflexa Roxb. vine have been extracted and assayed using the Xanthium cotyledon bioassay with N6-benzylaminopurine as the reference cytokinin. Maximum cytokinin level was found in the haustorial-bearing region with the gradient decreasing, towards the apex. The cytokinin content of the apex was less than 1% of that in the whole haustorial region. Interestingly, the concave half of the vine contained about forty times more cytokinin in the haustorial region than the corresponding convex half. The high concentration of cytokinin or cytokinin-like substances in the haustoria-bearing site in Cuscuta might be due either to a high RNase activity in the region or translocation from the host to parasite or both. [ABSTRACT FROM AUTHOR]