The “Malaria Evolution in South Asia” (MESA) program project is an International Center of Excellence for Malaria Research (ICEMR) sponsored by the US National Institutes of Health. This US–India collaborative program will study the origin of genetic diversity of malaria parasites and their selection on the Indian subcontinent. This knowledge should contribute to a better understanding of unexpected disease outbreaks and unpredictable disease presentations from Plasmodium falciparum and Plasmodium vivax infections. In this first of two reviews, we highlight malaria prevalence in India. In particular, we draw attention to variations in distribution of different human-parasites and different vectors, variation in drug resistance traits, and multiple forms of clinical presentations. Uneven malaria severity in India is often attributed to large discrepancies in health care accessibility as well as human migrations within the country and across neighboring borders. Poor access to health care goes hand in hand with poor reporting from some of the same areas, combining to possibly distort disease prevalence and death from malaria in some parts of India. Corrections are underway in the form of increased resources for disease control, greater engagement of village-level health workers for early diagnosis and treatment, and possibly new public–private partnerships activities accompanying traditional national malaria control programs in the most severely affected areas. A second accompanying review raises the possibility that, beyond uneven health care, evolutionary pressures may alter malaria parasites in ways that contribute to severe disease in India, particularly in the NE corridor of India bordering Myanmar Narayanasamy et al., 2012.

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 state dynamics of zinc­(II) 2,10,16,24-tetrakis­(9-phenyl-9H-carbazol-2-yl)­phthalocyanine (CBZPC1) and zinc­(II) 2,10,16,24-tetrakis­(4-(9H-carbazol-9-yl)­phenyl)­phthalocyanine (CBZPC2). Due to the presence of carbazole moieties, the Soret band was found to be broadened. The emission studies performed using different solvents revealed the fluorescence yields in the range of 0.10–0.27 and the time-resolved fluorescence data revealed radiative lifetimes of, typically, a few nanoseconds. Femtosecond transient absorption measurements indicated the formation of triplet states within the first nanosecond of photoexcitation. From the cyclic voltametric studies, the oxidation and reduction processes were found to be ring centered. Spectral changes in the UV–visible absorption were recorded by means of spectro-electrochemical analysis at an applied potential. The DFT and TD-DFT analysis was employed using B3LYP hybrid functional theory and 6-31G­(d,p) basis set in the Gaussian 09 package. The NLO properties of CBZPC1 and CBZPC2 were investigated using the Z-scan technique and femtosecond (fs) pulses with kHz and MHz repetition rates. Closed and open aperture Z-scan data were recorded at three different wavelengths of 600, 700, and 800 nm, and the NLO coefficients were extracted from both types of data. Two-photon absorption (TPA) was the dominant mechanism observed in the open aperture Z-scan data. The real and imaginary parts of the χ(3) along with the two-photon absorption cross sections were evaluated. Our NLO data and large 2PA coefficients and cross sections obtained indicate the potential of these compounds for applications in optical limiting and optical switching applications.

Antimony(III) halide based zero dimensional hybrids have gained interest as broadband emitters. Until now, quadrangular pyramidal SbX5 based and octahedral SbX6 based 0D hybrids have been reported utilizing different organic...

A comprehensive investigation is presented on the photophysical and third-order nonlinear optical (NLO) properties of two thioalkyl-substituted tetrathiafulvalene molecules (referred here as G1 and G3) to understand their utility as photosensitizers for dyesensitized solar cell (DSSC) and optoelectronic applications. Both steady-state and time-resolved (in the fs−ns time regime) absorption and photoluminescence (PL) spectroscopy techniques were employed to comprehend the excited-state properties of the molecules in solution as well as in thin films deposited on both quartz and mesoporous TiO 2 layers. The spectroscopy measurements in solution and thin films deposited on quartz provided the excited-state properties of dye molecules. Time-resolved PL measurements at the dye−TiO 2 interface provided initial evidence of electron injection by fast PL quenching decay dynamics for both the molecules. Detailed target analysis of the femtosecond transient absorption spectroscopy (TAS) data of the dye−TiO 2 sample revealed a multistep ultrafast electron injection for both molecules with the fastest injection component being 374 and 314 fs for G1 and G3 molecules, respectively. The ultrafast NLO properties of G1 and G3 were studied using the Z-scan technique with 800 nm, ∼70 fs laser pulses. The open aperture measurements showed three-photon absorption with magnitudes of coefficients 4.7 × 10 −5 cm 3 /GW 2 and 5.2 × 10 −5 cm 3 /GW 2 , and the closed aperture measurements provided second hyperpolarizability (γ) values of 3.5 × 10 −31 esu and 4.2 × 10 −31 esu for G1 and G3, respectively. Additionally, the onset of optical limiting was estimated to be 5.8 × 10 −3 J/cm 2 and 5.7 × 10 −3 J/cm 2 for G1 and G3 molecules, respectively.

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