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Reported here is a heterometallic 0D hybrid with constituent isolated metal halide units (Sb, Mn) that show strong synergistic interaction/coupling between the metal halide units (through Sb → Mn energy transfer) that results in enhanced emission.

We developed organelle-specific AIE luminogens with exceptional photophysical properties and mitochondrial targeting ability. These luminogens are ideal for diverse bioimaging applications, particularly for mitochondrial imaging.

We propose a dynamic (leveled) multi-key Fully Homomorphic Encryption (FHE) scheme under the learning with errors (LWE) assumption. Multi-key FHE in a dynamic setting is the most versatile variant of FHE which requires no information about the participating parties prior to key generation. In addition, it also introduces inputs from new parties into the computation. Designing dynamic multi-key FHE without blowing up the storage and ciphertext size of homomorphic computation is a challenging task. Unlike the existing LWE based multi-key FHE, our design does not use any common reference matrix in common parameter which seems to strengthen the power of using MFHE to allow users to generate their own keys independently. The ciphertext length and public key size of our construction are comparable to the existing similar works. We use only one component in the public extension key, resulting efficient extension of the ciphertexts under additional secret keys. The ciphertext in our design is generated using the FHE scheme of Gentry, Sahai, and Waters with no additional components, allowing efficient homomorphic evaluation. Our scheme is proven to be secure under standard LWE assumption without using circular security. More interestingly, our multi-key FHE is dynamic while maintaining ciphertext compactness.

Antimony(III) halide based zero dimensional hybrids have gained attention as broadband emitters. Until now, quadrangular pyramidal SbX5 based and octahedral SbX6 based 0D hybrids have been reported utilizing different organic ligands demonstrating some structural tunability affecting their emissive properties. Utilizing a common organic ligand, here we demonstrate the structural tunability (quadrangular pyramidal, octahedral, or a combination thereof) of the metal halide unit in Sb(III)Cl 0D hybrids with contrasting photo-physical properties (broadband, Stokes shift, strong/weak colored emission). The structure–property–mechanism correlation of the synthesized compounds [1 (C12H52Cl18N8O4Sb3; tris Sb green); 2 (C12H50Cl14N8O3Sb2; tris Sb red); 3 (C24H88Cl25N16O4Sb3; tris Sb yellow)] identifies crucial factors that control their emissive properties. The X-ray analysis reveals the structure (1-octahedral; 2-quadrangular pyramidal; 3-combination thereof) and the order of the extent of structural distortion as 1–3 ≪ 2. The metal halide coordination environment asymmetry and its structure are observed to dictate PL emission energy (1-green; 2-red; 3-yellow) as supported by a qualitative Molecular Orbital scheme. The extent of structural distortion guides the observed Stokes shifts (1–165 nm; 2–290 nm; 3–200 nm; 1–3 < 2). Interestingly, the extent of distortion is found to be well correlated with the observed PLQY (1–45%; 2–6%; 3–43%; 1–3 ≫ 2). This report clearly demonstrates the structural tunability and the effect of the metal halide unit structure/distortion in shaping the emissive properties of 0D organic Sb(III) halide hybrids.

Despite the current progress in ‘Pb-free’ low dimensional main group metal halide based luminescent materials, it is challenging to synthesize Te(IV) halide hybrids with strong ambient emission with excitation features in the visible range as efficient and stable phosphors for potential lighting applications. Reported here is a (benzyltriethylammonium)2TeCl6 zero dimensional hybrid material with excitation features in the visible range and strong room temperature, broadband, intrinsic luminescence (PLQY ∼15%) arising due to self-trapped excitons (STEs). Furthermore, a proof-of-concept LED architecture demonstrates successful optical down-conversion with a visible light excitation source. Here, exclusive adoption of a ‘regular’ octahedral Te(IV)-halide unit structure with minimal static distortion provides a unique opportunity to unmask the role played by 5s2 lone pair electrons in shaping the emissive properties. This effort may open up new avenues towards unravelling the role of lone pair stereoactivity in controlling the PLQY in low dimensional hybrids that has proven to be challenging for the reported (Sb, Sn) based low dimensional 5s2 metal halide hybrid materials.

Establishing secure transmissions of messages among the resource limited sensor nodes in wireless sensor network (WSN) is a critical issue and requires secret keys to be established among the communicating nodes. Key predistribution is the most commonly used technique and whereby secret keys are preloaded to the sensor nodes before their deployment into a hostile region. A WSN can be structured or unstructured, and sensor nodes may be deployed in an ad-hoc manner or pre-planned manner into the target field. As sensor nodes are low-cost electronic devices equipped with data processing, limited storage, communication and computation power, connectivity, and resiliency are the major focus in designing key predistribution scheme (KPS) for WSNs. Furthermore, we also expect the KPS to be scalable, enabling insertion of a set of new nodes in WSN at any point of time without altering the key setup of the already existing nodes. Combinatorial design is a widely used mathematical tool for the KPS. However, most of the KPS developed by using combinatorial design are not scalable. In this article, rather than using combinatorial techniques, we employ a code-based approach and design a new method for key predistribution by building a communication model and a connectivity model. We exploit the Reed Solomon code to establish our communication model, integrate the binary Goppa code to derive our connectivity model, and skillfully blend these two models to construct our code-based KPS. A C implementation of our KPS confirms the significant performance gain over the existing similar works. Additionally, nodes in our KPS are all self-dependent for communication and do not rely on cluster heads. Furthermore, we have control over the choice of the parameters in the underlying codes which makes our KPS flexible. To be specific, prior knowledge of additional node deployment increases the scalability of our connectivity model. By suitably choosing the parameters of the Goppa code at prior, we can accommodate extra nodes. More interestingly, our communication model is scalable without any previous knowledge of deployment.

A series of hybrid organic bipolar fluorescent aggregation-induced emission (AIE) luminogens have been synthesized with D–π–A architecture using phenanthroimidazole as a conjugate by incorporating a fluorenone moiety at the C2 position of a rigid skeleton of 1,2-diphenyl-1H-phenanthro[9,10-d]imidazole. The synthesis was achieved by the Suzuki coupling reaction between 2-(4-bromophenyl)-1-phenyl-1H-phenanthro[9,10-d]imidazole and 2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9H-fluoren-9-one. All derivatives of the product were found to be thermally stable, with high melting and high decomposition temperatures. The phenanthroimidazoles P1–P5 displayed the natural properties of AIE. Wide colour contrast between the green and yellow regions was demonstrated by these luminogens. Among them, P1 displayed higher quantum yield and long lifetime properties. Thus, the obtained results clearly demonstrate that all the luminogens are promising materials for research and use in optoelectronic devices, sensing applications, biological probes and intercellular imaging.

Low dimensional (2D, 1D) lead halide perovskites are currently attracting huge research interest due to their enabling properties. Demonstrating synthetic control on the dimensionality/structure of...

An all-inclusive investigation of the ultrafast excited state relaxation dynamics of a triphenylmethane derivative molecule, New Fuchsine (NF), using a combined approach of density functional theory (DFT), femtosecond transient absorption spectroscopy (fs-TAS), and photoluminescence spectroscopy is presented in this work. The DFT calculations confirmed the formation of twisted molecular structure in the excited state of NF in ethanol solution with bond rotation of ≈ 860 . TAS measurements of NF solution exhibited ultrafast ground state-recovery pathway via a conical intersection confirming an ultrafast structural reorientation. On the contrary, TAS measurements of NF thin-film exhibited a longer excited-state lifetime suggesting a hindered molecular twisted state formed as an intermediate step. Photophysical kinetic models are proposed to globally fit the fs-TAS data establishing the twisted intramolecular charge transfer (TICT) state mediated ground state recovery for NF in solution and thin film, respectively. Temperature-dependent photoluminescence study of NF film provided a clear insight into the effect of rotational motion of phenyl rings in NF molecules over the TICT mediated emission.

We report our results from the investigations of linear and ultrafast nonlinear optical properties of a set of pyrrolo[1,2-a]quinoxalines. Using the steady state optical techniques and density functional theory calculations the linear optical properties were investigated while the non-resonant ultrafast nonlinear optical properties were studied using the degenerate four-wave mixing technique at a wavelength of 800 nm with 70 fs pulses. The investigated molecules demonstrated large off-resonant second hyperpolarizability ( γ ) and nonlinear refractive index ( n 2 ) values compared to similar molecular moieties with potential application in optical devices.

In this paper, we present results from the detailed investigations on the synthesis, optical, emission, electrochemical, and ultrafast nonlinear optical (NLO) properties along with the excited stat...

A novel zinc phthalocyanine derivative [2(3), 9(10), 16(17), 23(24) tetrakis-4-((4-(1,4,5-triphenyl-1H-imidazol-2-yl)phenyl)ethynyl)phthalocyanine zinc(II) (PBIPC)] was synthesized by incorporating a triphenyl imidazole moiety at its peripheral positions. The detailed mechanisms of absorption, emission, electrochemical, nonlinear optical (NLO) and photophysical (excited state dynamics) properties of PBIPC were explored. The absorption and emission properties of the compound were studied in different solvents. The incorporation of a triphenyl imidazole moiety at the peripheral position of the zinc phthalocyanine slightly broadened the Soret band. The emission studies revealed fluorescence quantum yields to be in the range of 0.11–0.22. The time-resolved fluorescence data established the radiative lifetimes to be in the nanosecond range. The oxidation and reduction processes were found to be ring centered, which were studied using the cyclic voltammetry (CV) technique. The energy optimized structures and HOMO–LUMO levels were calculated using DFT, TD-DFT analysis and were employed by means of hybrid functional theory (B3LYP) at 6-31G (d,p) basis set in the Gaussian 09 package. Two-photon absorption was observed in the NLO studies performed in the visible wavelength range of 600–800 nm while the nonlinear absorption was dominated by three- and four-photon absorption processes in the NIR wavelength range (1.0–1.5 μm). The molecule exhibited self-focusing behavior for all the wavelengths. Finally, the excited state dynamics of the title molecule PBIPC were investigated using femtosecond transient absorption spectroscopy and the results obtained were understood on the basis of a simple three kinetic model, for excitation wavelengths of 400 nm (Soret band) and 650 nm (Q-band). Both the spectra demonstrated a broad positive transient absorption (TA) data which overlapped with the ground state bleach (GSB), which in turn displayed a red shift over a delay of ∼2 ns. The lifetimes revealed a possibility of intersystem crossing (τ > 1 ns) owing to the triplet state transition.

A survey was carried out to investigate culture strategies, disease patterns and mitigations in mono-sex Nile tilapia in Jessore sadar region. Data obtained by questionnaire interview, individual interview, telephonic interview, PRA method, mono-sex Nile tilapia farm survey from four villages. It was observed that 30.769% farmers and farm owner had no training about culture of mono-sex Nile tilapia while 69.230% farmers and farm owner received short term training from different Department of Fisheries, different NGOs. Mono-sex Nile tilapia culture in ponds was basically a three-tier culture system. Pre-stocking management of ponds in the study area comprised dike repairing, aquatic weed control, waste soil removal and undesirable species (predator and trash fish) control. Majority (85%) of the farm owners and farmers depends on ground water and only (15%) depends on surface water. About 95% of farm of farm owners controlled aquatic weeds manually. Removal of predatory and undesired fish from pond used different types of chemicals but most used rotenone (80%). Fertilizer of pond preparation (Organic and inorganic) in the study area but mostly used cases inorganic fertilizers had applied at the rate of urea 114 kg/ha and triple superphosphate 60 kg/ha in 4–5 installments. Stocking density of mono-sex Nile tilapia was 200-380 fry per decimal. It was recorded that 85% of mono-sex Nile tilapia farmers and farm owner applied supplementary such as commercially manufactured feed and 12% are applied of farm made feed. It was observed,they provided heavy fertilizer, high stocking density, over feed provided, provided over dose drugs so ultimated result of disease occured. Parasitic related disease, bacterial diseases, fungal diseases, viral diseases were attacked in mono-sex Nile tilapia. Argulosis and Streptococcus were mostly common disease in this mono-sex Nile tilapia farm. Asian Australas. J. Biosci. Biotechnol. 2018, 3 (3), 190-200

Thiosemicarbazone metal complexes [Cu(L)(2-benzpy)]ClO4 (1) and [Zn(L)2] (2) [L = 2-benzoylpyridine-N(4)-methyl-3-thiosemicarbazone), 2-benzpy = 2-benzolylpyridine] were synthesized and X-ray crystallographically characterized. The metal centre in compound 1 has a distorted square planar geometry while in compound 2, the metal centre has a distorted octahedral geometry. Both the molecules induce cytotoxic effects on A431 skin carcinoma cell line in 24 h incubation and significantly enhances hypoploid cell population in cell cycle phase distribution below IC50 dose. Application of both the two molecules exhibit apoptotic induction and genotoxic activity in 24 h exposure.

The analytical experiment was executed to present detailed reports on the concentration of heavy metals (nickel, iron, zinc, manganese, chromium, lead, and cadmium) in farmed shrimp, Penaeus monodon and its concomitant human health risks upon consumption. A total of 147 farms from six sub-districts of Khulna were selected for sample collection and concentration of heavy metals were determined by Atomic Absorption Spectrometry (AAS) method, following electro-thermal heater digestion. Ni and Cr were found considerably below the detectable limit (BDL) in four sub-districts, while Cr found in shrimps from Rupsa and Paikgacha were far higher than the maximum recommended limit defined by FAO and WHO. The average concentrations of Fe and Mn in all sub-districts crossed the recommendations, whereas average concentrations of Zn, Ni, Cd, and Pb were within the recommendations. Regardless of sampling site, target hazard quotients (THQ) of more than 1 contributed by Fe confirmed higher level of hazard index (HI), indicating potential human health risk. Fortunately, no heavy metal or their additive effect found to offer lifetime potency of carcinogenesis upon consumption of these shrimps. Therefore, probabilistic non-carcinogenic human health risk from Fe contamination necessitates stringent monitoring and controlling of this metal from different sources to farms.

Enhancement NIR emission from co-doped (Er-Nd)TiO2 samples is investigated. Analysis revealed interesting bi-direction energy transfer from both Rare-Earth (RE) sites, the interplay of which results in enhanced NIR emission.

The ultrafast NLO properties of diketopyrrolopyrrole substituted zinc (II) porphyrin molecules are presented here. Intensity-dependent z-scan measurements presenting RSA followed by SA, were analysed using a phenomenological model based on two-photon absorptions.

The analytical experiment was executed to present detailed reports on the concentration of heavy metals (nickel, iron, zinc, manganese, chromium, lead, and cadmium) in farmed shrimp, Penaeus monodon and its concomitant human health risks upon consumption. A total of 147 farms from six sub-districts of Khulna were selected for sample collection and concentration of heavy metals were determined by Atomic Absorption Spectrometry (AAS) method, following electro-thermal heater digestion. Ni and Cr were found considerably below the detectable limit (BDL) in four sub-districts, while Cr found in shrimps from Rupsa and Paikgacha were far higher than the maximum recommended limit defined by FAO and WHO. The average concentrations of Fe and Mn in all sub-districts crossed the recommendations, whereas average concentrations of Zn, Ni, Cd, and Pb were within the recommendations. Regardless of sampling site, target hazard quotients (THQ) of more than 1 contributed by Fe confirmed higher level of hazard index (HI), indicating potential human health risk. Fortunately, no heavy metal or their additive effect found to offer lifetime potency of carcinogenesis upon consumption of these shrimps. Therefore, probabilistic non-carcinogenic human health risk from Fe contamination necessitates stringent monitoring and controlling of this metal from different sources to farms., Heavy metals; Food safety; Human health risk assessment; Shrimp (Penaeus monodon)

Herein, results from the investigation of ultrafast photophysical and third-order nonlinear optical properties of newly synthesized Zn phthalocyanine, namely [Zinc (II) 2,10,16,24tetrakis(2,6-dichloropyridin-3-yl) phthalocyanine, PyCl2PC] molecule are presented. The photophysical properties were studied using femtosecond transient absorption spectroscopy while the NLO properties were measured using the single beam Z-scan and degenerate four-wave mixing (DFWM) techniques. The transient absorption spectra were obtained at 400 nm photoexcitation and a white light continuum probed the corresponding dynamics from (440-780 nm) in the solution phase. The obtained transient absorption spectra were globally fitted using a kinetic model which yielded the different photophysical constants after photoexcitation such as (i) internal conversion from higher electronic excited state (Sn) to lower electronic state (S1) happening in 1 ps (ii) Vibrational relaxation (6.25 ps) occurring within the S1 states (III) Intersystem crossing (1.78 ns) (IV) relaxation from the triplet states to ground state (0.11 μs). Nonlinear absorption properties were measured at 800 nm wavelength utilizing ~70 fs, 1 kHz laser pulses in the solution phase. A large two-photon absorption coefficient (β) of ~8×10-13 cm/W was obtained and the corresponding cross-section was estimated to be 659 GM. Time-resolved degenerate four-wave-mixing measurements revealed a large magnitude and an ultrafast response of χ(3).

Ultrafast excited-state molecular relaxation process in a triphenylmethane derivative dye New Fuchsin (NF) for dye-sensitized solar cell application in solution and thin film is studied using femtosecond pump-probe spectroscopy at pump excitation wavelength 550 nm.

The excited state intramolecular proton transfer has been observed in two Novel Phenanthroimidazole derivative molecules in aqueous solution of the molecules. Formation of new excited state species and large stokes shift of emission ~0.38eV for F3 and 0.49 eV for F5 has been recorded, suggesting their potential application in chemical and biological probing and imaging.

Ultrafast excited state molecular relaxation process in a ethynylthiophene functionalized D--A porphyrin (LG5) molecule sensitizer in solution and thin film form has been studied using femtosecond transient absorption techniques upon pumping with 400 nm.

Silver (Ag) nanoparticle induced enhanced electron-injection and reduced charge-recombination dynamics in two thioalkyl substituted tetrathiafulvalene dye (G1 and G3)- sensitized mesoporous TiO2 layers have been investigated using femtosecond transient-absorption spectroscopy with 400 nm excitation.

BACKGROUND Acute Myocardial Infarction (AMI) is a leading cause of morbidity and mortality globally. Efforts are always there to identify predisposing risk factors associated with development of AMI so that preventive approaches can be adopted for therapeutic interventions or life style changes. This study was conceptualized to identify the responsible risk factors with AMI & to evaluate their power of association. An approach was also adopted to identify whether co-existence of deficiency of vitamin D (25(OH) D) along with the classic risk factors further endangers the population. The objectives of the study were- 1) To identify risk factors of AMI & to evaluate their power of association. 2) To estimate vitamin D level in all cases and controls and to study statistical correlation of vitamin D with classic risk factors. MATERIALS AND METHODS It is a case control study, where 130 cases of AMI & 130 healthy controls from patient’s attendants were included. Patients were evaluated clinically, and investigations were done to identify the classic risk factors. Simultaneously vitamin D (25(OH) D) level was estimated in all cases and controls. Results obtained were analysed statistically to evaluate the power of association of the risk factors. The statistical package for social science version 16 IBM Corporation was used for statistical analysis and P Value of

BACKGROUND Acute myocardial infarction (AMI) is a major concern globally and recent studies explored the role of vitamin D deficiency as one of the predisposing factors and documented its deleterious effect both in mortality and morbidity associated with the incident. Apart from its usual role of maintaining calcium homeostasis in humans new found role of vitamin D as a risk factor in cardiovascular incidents have gathered interest and it was proven by various studies available in literature that Vitamin D deficiency adversely affects post MI cardiac remodelling. So, hypovitaminosis D is also a major concern and needs therapeutic interventions. The present study was done with an aim to reveal any association existing between AMI cases & Vitamin D deficiency. Aims and objectives- To study Vitamin D (25(OH)D) level in AMI cases and to study any significant statistical association existing between AMI cases & Vitamin D level. MATERIALS AND METHODS It is a case control study conducted at Agartala Government Medical College, Agartala, Tripura, at Department of Medicine, where 130 patients of AMI are included and they underwent necessary biochemical investigations including 25(OH) D. These values were compared with the values of 25(OH) D done on 130 healthy controls matched with same age and gender. The Statistical Package for Social Science version 16 IBM Corporation was used for analysis. P value of P < 0.05 was considered significant. RESULTS The mean value of 25(OH) D among the cases was 20.39±6.96 and among the healthy controls was 24.08±7.68. Experts opine that the normal value of Vitamin D in humans is ≥30 ng/ml. With P Value

Introduction:- Infection prevention and control is an integral component of health care delivery in any setting to reduce risks for morbidity and mortality in patients and care givers at all levels. The practice of hand hygiene by health care workers, through the use of either soap and water or an alcohol-based hand sanitizer, is widely considered to be the most important and effective means of preventing health care – associated infections. Objective: To assess knowledge, attitude and practices of health care providers regarding hand washing. Materials and methods:- An institutional based cross sectional study was carried out in outdoor patient, indoor ward among 193 health care providers (doctors, nursing staffs, OT assistants, laboratory technicians, ward boys and ward girls) in a Tertiary Care Hospital of Tripura from September – October 2017. A pre-tested questionnaire was used as study tool to collect information on knowledge, attitude and practices about hand washing. Result:- Majority (73.6%) of the populations was among 18-25 years age group with a female predominance (70.5% females) and most of them were Hindu (94.5%). Most of them (97.5%) know about the importance of hand washing. Around (48.3%) wash hand with soap followed by liquid hand wash (44%) that showed (91%) washed hands with soap and water. Conclusion:-The current study revealed the knowledge, attitude and absence of sufficient practice of hand washing among health care providers. Future studies in this context are recommended to further determine the factors responsible for these lacunae. Also there is a need to educate the health care workers about hand washing practices and to periodically train them about the six steps of hand washing.

Excited-state dynamics of two novel energetic nitrogen-rich aryl-tetrazole molecules were investigated using femtosecond transient absorption spectroscopy. The internal conversion from Sn to S1 occurred in the 0.3–0.5 ps; vibrational relaxation within S1 states transpired in a 1.8–5 ps time scale and, subsequently, the intersystem crossing was observed with lifetimes of 7.8 ps and 129 ps. The nitro-substituted tetrazole demonstrated a faster decay with a weaker fluorescence compared to the amino-substituted derivative. We believe that the high nitrogen content in the former resulted in a possible more rapid nonradiative decay.

Charge photogeneration by exciton dissociation at the donor/acceptor interface is the heart of organic molecule–based devices for solar energy conversion. Femtosecond pump–probe spectroscopy offers a noninvasive technique to follow the charge photogeneration. In this article, we elucidate the contribution of femtosecond pump–probe spectroscopy in providing in‐depth insights into various photophysical aspects that aid in the development of efficient organic molecule–based solar cells, namely, dye‐sensitized solar cells, organic–inorganic hybrid solar cells, polymer‐based bulk heterojunction solar cells, and perovskite solar cells.

We have investigated the photo-physical properties and broadband third-order nonlinear optical properties of a novel Zinc phthalocyanine, PBI-Pc, employing femtosecond transient absorption and the Z-scan technique, respectively, using 1 kHz femtosecond pulses.

Herein, we report results from our studies on the ultrafast nonlinear optical (NLO) properties and excited-state dynamics in three different porphyrin molecules designed in D-π-D fashion (phenothiazine-porphyrin-phenothiazine) and with two different central metal ions [Zn(II) and Cu(II)]. We have performed extensive target analysis of the femtosecond transient absorption data obtained conveying the true exited state/species spectra of each process with respective lifetimes along with microscopic rate constants of each excited state. The obtained life time values were in the range of 250–500 fs, 20–142 ps, 1.5–6.2 ns and 0.1–1.23 μs and have been associated from relaxation with the Sn, Hot S1 (to S1), S1, and T1 states. Furthermore, the third-order nonlinear (NLO) coefficients [two-photon absorption (TPA) and nonlinear refractive index (n2)] of CPPHT and ZPPHT exhibited superior values compared to HPPHT recorded with ~50 fs, 1 kHz repetition rate pulses at a wavelength of 800 nm. The magnitude of the TPA coefficients of these molecules was compared with some of the recently reported porphyrin moieties and were found to be superior. The time-resolved degenerate four-wave mixing (DFWM) measurements confirmed a large magnitude and an ultrafast response of the χ(3) in these molecules suggesting potential photonic and all-optical switching applications.

The progression in synthetic procedures over the last two decades gave admittance to a wide variety of corroles for suitable potential applications such as photovoltaics, photonics, and bio-imaging. In this communication, we present results from our investigations of ultrafast photophysical processes and third-order nonlinear optical properties of newly synthesized donor-acceptor based free-base [(C6F5)3] and phosphorus [P-(OH)2(C6F5)3] corroles. The global analysis of the femtosecond transient absorption data based on the compartmental model revealed the corresponding time constants of several photophysical processes such as (a) internal conversion (τIC) in the 260–280 fs range (b) vibrational relaxation (τVR) in the 2.5-5 ps range and (c) nonradiative relaxation times (τnr) in the 4.15–7.6 ns range and finally (d) triplet lifetimes in the range of 25–50 μs. The two-photon absorption (TPA) cross-section measurements were performed using the femtosecond, kHz pulse Z-Scan technique at 600 nm and 800 nm and the retrieved TPA cross-section values were in the range of ~102 GM. Degenerate four-wave mixing measurements illustrated a large third-order nonlinear optical susceptibility χ(3) with a magnitude of 6.9 × 10−14 esu and instantaneous (sub-picosecond) response, suggesting a pure electronic contribution to the nonlinearity of these corroles. The discoveries from this study may help further to extend the capability of corroles as NLO materials for photonic applications.

Logos sometimes also known as trademark have high importance in today’s marketing world. Logo or trademark is of high importance because it carries the goodwill of the company and the product. Logo matching and recognition is important to discover either improper or unauthorized use of logos. Query images may come with different types of scale, rotation, affine distortion, illumination noise, highly occluded noise. Sift descriptor, surf descriptor and hog descriptor are very good features to use among the existing techniques to recognize the logo images from such difficulties more accurately. General Terms Logo Recognition, invariant to scale, rotation, invariant to illumination noise, occluded objects .

Polarization properties of white-light continuum due to a single femtosecond filament inside a YVO4 crystal are investigated at different input laser powers. The results show the depolarization of the white-light continuum at high powers.