The Cloud Aerosol Interaction and Precipitation Enhancement Experiment (CAIPEEX): overview and preliminary results

While the demand for enhancing rainfall through cloud seeding is strong and persistent in the country, considerable uncertainty exists on the success of such an endeavour at a given location. To understand the pathways of aerosol-cloud interaction through which this might be achieved, a national experiment named Cloud Aerosol Interaction and Precipitation Enhancement EXperiment (CAIPEEX) in two phases, was carried out. The rationale of CAIPEEX, the strategy for conducting the experiment, data quality and potential for path-breaking science are described in this article. Pending completion of quality control and calibration of the CAIPEEX phase-II data, here we present some initial results of CAIPEEX phase-I aimed at documenting the prevailing microphysical characteristics of aerosols and clouds and associated environmental conditions over different regions of the country and under different monsoon conditions with the help of an instrumented research aircraft. First-time simultaneous observations of aerosol, cloud condensation nuclei (CCN) and cloud droplet number concentration (CDNC) over the Ganges Valley during monsoon season show very high concentrations (> 1000 cm-3) of CCN at elevated layers. Observations of elevated layers with high aerosol concentration over the Gangetic valley extending up to 6 km and relatively less aerosol concentration in the boundary layer are also documented. We also present evidence of strong cloud- aerosol interaction in the moist environments with an increase in the cloud droplet effective radius. Our observations also show that pollution increases CDNC and the warm rain depth, and delays its initiation. The critical effective radius for warm rain initiation is found to be between 10 and 12 µm in the polluted clouds and it is between 12 and 14 µm in cleaner monsoon clouds

Humanized Mouse Model of Ovarian Cancer Recapitulates Patient Solid Tumor Progression, Ascites Formation, and Metastasis

Ovarian cancer is the most common cause of death from gynecological cancer. Understanding the biology of this disease, particularly how tumor-associated lymphocytes and fibroblasts contribute to the progression and metastasis of the tumor, has been impeded by the lack of a suitable tumor xenograft model. We report a simple and reproducible system in which the tumor and tumor stroma are successfully engrafted into NOD-scid IL2Rγnull (NSG) mice. This is achieved by injecting tumor cell aggregates derived from fresh ovarian tumor biopsy tissues (including tumor cells, and tumor-associated lymphocytes and fibroblasts) i.p. into NSG mice. Tumor progression in these mice closely parallels many of the events that are observed in ovarian cancer patients. Tumors establish in the omentum, ovaries, liver, spleen, uterus, and pancreas. Tumor growth is initially very slow and progressive within the peritoneal cavity with an ultimate development of tumor ascites, spontaneous metastasis to the lung, increasing serum and ascites levels of CA125, and the retention of tumor-associated human fibroblasts and lymphocytes that remain functional and responsive to cytokines for prolonged periods. With this model one will be able to determine how fibroblasts and lymphocytes within the tumor microenvironment may contribute to tumor growth and metastasis, and will make it possible to evaluate the efficacy of therapies that are designed to target these cells in the tumor stroma

Oceansat-1 derived met-ocean parameters during various stages of monsoon depression of June 1999, along Orissa coastline, east coast of India

113-121After the launch of Oceansat-1 (IRS-P4) on May 26, 1999, weather scientists got the opportunity to study some of the meteorological and oceanographic (met-ocean) parameters associated with the weather systems formed over the oceanic regions around India, even under cloudy conditions. Oceansat-1 carries multifrequency scanning microwave radiometer (MSMR) which has a capability to provide information of certain parameters viz. sea surface wind speeds (SSW), sea surface temperature (SST), integrated water vapour (IWV) and cloud liquid water content (CLW). A monsoon depression was formed over the Bay of Bengal on 17 June 1999 causing widespread rainfall over Orissa coast and the adjoining regions. Oceansat-1 derived met-ocean parameters were studied during various stages of this depression. The maximum values of these parameters during the life cycle of the depression over the Bay of Bengal were SST : 30º - 31º C, SSW : 16-18 m/s, IWV : 7.0 g/cm², CLW : 90-100 mg/cm². It was observed that SSW, IWV and CLW show high values one to three days before the formation of the depression. High values, shape and steep gradients of the met-ocean parameters give prior indication of formation/intensification of the weather system and its probable location. SST reduced by about 1º-2º after the passage of the low pressure system over the region

Orissa super cyclone of October 1999 as revealed by IRS-P4 satellite data

35-42A super cyclone hit Orissa coast during 24-31 Oct. 1999 causing vast damage to property and life. Life cycle of this super cyclonic storm from its genesis to landfall is studied using IRS-P4 satellite derived parameters over the oceanic region. The parameters, viz. sea surface temperature, sea surface wind, integrated water vapour, cloud liquid water content are studied over the region 5-25° N and 70-100°E. Synoptic surface pressure charts were compared with INSAT imagery. The IRS-P4 satellite data supplemented the data from INSAT in studying various characteristics associated with the super cyclone

Biocompatible Magnetite/Gold Nanohybrid Contrast Agents via Green Chemistry for MRI and CT Bioimaging

Magnetite/gold (Fe₃O₄/Au) hybrid nanoparticles were synthesized from a single iron precursor (ferric chloride) through a green chemistry route using grape seed proanthocyanidin as the reducing agent. Structural and physicochemical characterization proved the nanohybrid to be crystalline, with spherical morphology and size ∼35 nm. Magnetic resonance imaging and magnetization studies revealed that the Fe₃O₄ component of the hybrid provided superparamagnetism, with dark T₂ contrast and high relaxivity (124.2 ± 3.02 mM^–1 s^–1). Phantom computed tomographic imaging demonstrated good X-ray contrast, which can be attributed to the presence of the nanogold component in the hybrid. Considering the potential application of this bimodal nanoconstruct for stem cell tracking and imaging, we have conducted compatibility studies on human Mesenchymal Stem Cells (hMSCs), wherein cell viability, apoptosis, and intracellular reactive oxygen species (ROS) generation due to the particle–cell interaction were asessed. It was noted that the material showed good biocompatibility even for high concentrations of 500 μg/mL and up to 48 h incubation, with no apoptotic signals or ROS generation. Cellular uptake of the nanomaterial was visualized using confocal microscopy and prussian blue staining. The presence of the nanohybrids were clearly visualized in the intracytoplasmic region of the cell, which is desirable for efficient imaging of stem cells in addition to the cytocompatible nature of the hybrids. Our work is a good demonstrative example of the use of green aqueous chemistry through the employment of phytochemicals for the room temperature synthesis of complex hybrid nanomaterials with multimodal functionalities

Biocompatible Magnetite/Gold Nanohybrid Contrast Agents via Green Chemistry for MRI and CT Bioimaging

Magnetite/gold (Fe₃O₄/Au) hybrid nanoparticles were synthesized from a single iron precursor (ferric chloride) through a green chemistry route using grape seed proanthocyanidin as the reducing agent. Structural and physicochemical characterization proved the nanohybrid to be crystalline, with spherical morphology and size ∼35 nm. Magnetic resonance imaging and magnetization studies revealed that the Fe₃O₄ component of the hybrid provided superparamagnetism, with dark T₂ contrast and high relaxivity (124.2 ± 3.02 mM^–1 s^–1). Phantom computed tomographic imaging demonstrated good X-ray contrast, which can be attributed to the presence of the nanogold component in the hybrid. Considering the potential application of this bimodal nanoconstruct for stem cell tracking and imaging, we have conducted compatibility studies on human Mesenchymal Stem Cells (hMSCs), wherein cell viability, apoptosis, and intracellular reactive oxygen species (ROS) generation due to the particle–cell interaction were asessed. It was noted that the material showed good biocompatibility even for high concentrations of 500 μg/mL and up to 48 h incubation, with no apoptotic signals or ROS generation. Cellular uptake of the nanomaterial was visualized using confocal microscopy and prussian blue staining. The presence of the nanohybrids were clearly visualized in the intracytoplasmic region of the cell, which is desirable for efficient imaging of stem cells in addition to the cytocompatible nature of the hybrids. Our work is a good demonstrative example of the use of green aqueous chemistry through the employment of phytochemicals for the room temperature synthesis of complex hybrid nanomaterials with multimodal functionalities

Biocompatible Magnetite/Gold Nanohybrid Contrast Agents via Green Chemistry for MRI and CT Bioimaging

Magnetite/gold (Fe₃O₄/Au) hybrid nanoparticles were synthesized from a single iron precursor (ferric chloride) through a green chemistry route using grape seed proanthocyanidin as the reducing agent. Structural and physicochemical characterization proved the nanohybrid to be crystalline, with spherical morphology and size ∼35 nm. Magnetic resonance imaging and magnetization studies revealed that the Fe₃O₄ component of the hybrid provided superparamagnetism, with dark T₂ contrast and high relaxivity (124.2 ± 3.02 mM^–1 s^–1). Phantom computed tomographic imaging demonstrated good X-ray contrast, which can be attributed to the presence of the nanogold component in the hybrid. Considering the potential application of this bimodal nanoconstruct for stem cell tracking and imaging, we have conducted compatibility studies on human Mesenchymal Stem Cells (hMSCs), wherein cell viability, apoptosis, and intracellular reactive oxygen species (ROS) generation due to the particle–cell interaction were asessed. It was noted that the material showed good biocompatibility even for high concentrations of 500 μg/mL and up to 48 h incubation, with no apoptotic signals or ROS generation. Cellular uptake of the nanomaterial was visualized using confocal microscopy and prussian blue staining. The presence of the nanohybrids were clearly visualized in the intracytoplasmic region of the cell, which is desirable for efficient imaging of stem cells in addition to the cytocompatible nature of the hybrids. Our work is a good demonstrative example of the use of green aqueous chemistry through the employment of phytochemicals for the room temperature synthesis of complex hybrid nanomaterials with multimodal functionalities

Biocompatible Magnetite/Gold Nanohybrid Contrast Agents via Green Chemistry for MRI and CT Bioimaging

Magnetite/gold (Fe₃O₄/Au) hybrid nanoparticles were synthesized from a single iron precursor (ferric chloride) through a green chemistry route using grape seed proanthocyanidin as the reducing agent. Structural and physicochemical characterization proved the nanohybrid to be crystalline, with spherical morphology and size ∼35 nm. Magnetic resonance imaging and magnetization studies revealed that the Fe₃O₄ component of the hybrid provided superparamagnetism, with dark T₂ contrast and high relaxivity (124.2 ± 3.02 mM^–1 s^–1). Phantom computed tomographic imaging demonstrated good X-ray contrast, which can be attributed to the presence of the nanogold component in the hybrid. Considering the potential application of this bimodal nanoconstruct for stem cell tracking and imaging, we have conducted compatibility studies on human Mesenchymal Stem Cells (hMSCs), wherein cell viability, apoptosis, and intracellular reactive oxygen species (ROS) generation due to the particle–cell interaction were asessed. It was noted that the material showed good biocompatibility even for high concentrations of 500 μg/mL and up to 48 h incubation, with no apoptotic signals or ROS generation. Cellular uptake of the nanomaterial was visualized using confocal microscopy and prussian blue staining. The presence of the nanohybrids were clearly visualized in the intracytoplasmic region of the cell, which is desirable for efficient imaging of stem cells in addition to the cytocompatible nature of the hybrids. Our work is a good demonstrative example of the use of green aqueous chemistry through the employment of phytochemicals for the room temperature synthesis of complex hybrid nanomaterials with multimodal functionalities