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Acanthus ilicifolius is a spiny semi-woody evergreen shrub which is one of the most dominant mangrove associate species. Although its floral biology is well documented, there is not enough systematic study of floral visitors of this species. Successful plant reproduction is highly dependent on plant-pollinator interaction. The present study aims to understand the range of floral visitors of A. ilicifolius and their spatio-temporal variation in visitation pattern from the Indian Sundarbans. This study was conducted in five islands of Sundarbans Biosphere Reserve (SBR), namely, Bali, Gosaba, Satjelia, Gangasagar and Bakkhali during 2015 and 2016. Fifteen flower visitors under five taxonomic orders, i.e., Hymenoptera, Coleoptera, Diptera, Lepidoptera and Passeriformes were identified. Seven out of these fifteen species were reported for the first time as floral visitor of A. ilicifolius. Order Hymenoptera was the most frequent insect group, whereas Apis mellifera of this order was the predominant flower visitor. Although Gangasagar and Bakkhali being tourist spots, face greater anthropogenic interference, they had the highest abundance of floral visitors. A significant variation in floral visitor abundance was observed across different time of the day throughout the study period. Floral visitors were most abundant in the morning between 8 a.m. to 12 p.m. This study provides the first comprehensive report of diversity and abundance of the floral visitors and their visitation pattern on A. ilicifolius. Implications for insect conservation: Proper documentation of the ecology of insect pollinators would automatically help to conserve the plants along with the insects, and thus preserve the entire mangrove ecosystem of the Sundarbans as well as mangroves around the world.

In a nanocomposite of reduced graphene oxide (RGO) and BiFeO$_3$ (BFO), the remanent ferroelectric polarization is found to follow nonmonotonic magnetic field dependence at room temperature as the applied magnetic field is swept across 0-20 kOe on a pristine sample. The remanent ferroelectric polarization is determined both from direct electrical measurements on an assembly of nanoparticles and powder neutron diffraction patterns recorded under 0-20 kOe field. The nanosized ($\sim$20 nm) particles of BFO are anchored onto the graphene sheets of RGO via Fe-C bonds with concomitant rise in covalency in the Fe-O bonds. The field-dependent competition between the positive and negative magnetoelectric coupling arising from magnetostriction due to, respectively, interface and bulk magnetization appears to be giving rise to the observed nonmonotonic field dependence of polarization. The emergence of Fe-C bonds and consequent change in the magnetic and electronic structure of the interface region has influenced the coupling between ferroelectric and magnetic properties remarkably and thus creates a new way of tuning the magnetoelectric properties via reconstruction of interfaces in nanocomposites or heterostructures of graphene/single-phase-multiferroic systems., Comment: 10 pages, 12 figures, comments are welcome

Background: Myopia is a refractive error in which parallel rays of light coming from infinity are focused in front of the retina when accommodation remains at rest. Myopia has emerged as one of the crucial public health problems in the urban population of India. The prevalence of myopia varies with different factors. It is one of the major cause of the visual impairment in the developed and in the developing world. Aim: To evaluate the efficacy of homoeopathic medicines for reducing and arresting the present refractive error of myopia. Design: This is a prospective, experimental, longitudinal, non – randomized, single blinded, clinical study. Methods: This study on myopia was performed on a sample size of 40, age group of 7-30 years with a duration of almost 6 months. After the screening process, the selected patients went through optometric evaluation followed by a proper case taking with the best suitable homoeopathic medicines. Based on the individualisation and called for subsequent visits for five more times. In every visit each of them were assessed by Likert scale. Result: After 6 months of the study, although significant changes were seen in each case as per Likert scale scoring for subjective symptoms, no significant changes in degree of myopia were observed clinically. Conclusion: Although the result was statistically significant in showing that there was a control in myopia progression, but for getting a firm conclusion of the same, this study needs to be carried out for longer duration.

The solubility of solid phenanthrene (PHE) powder in aqueous solutions of surfactant and chitosan (CS) was evaluated by varying the composition of aqueous mixtures. Cetyltrimethyl ammoniumbromide (CTAB) and sodium dodecyl sulfate (SDS) were used as model cationic and anionic surfactants, respectively. CS at a particular concentration in the mixture especially above the CMC value of the anionic surfactant exhibited somewhat higher PHE solubility values than surfactant itself. CS (20 mg/l)-SDS (20 g/l) solution showed higher PHE solubility (422.05 mg/l) than that of 20 g/l SDS (377.92 mg/g). However, CS-CTAB did not show any additional enhancing effect on PHE solubilization, and CS (5 mg/l)-CTAB (10 g/l) solution showed almost similar PHE solubility (867.23 mg/l) of 10 g/l CTAB (865.25 mg/g). The maximum increase in absorbance value of a 20 ml CS solution (5, 20 and 100 mg/l) at 540 nm with stepwise addition of SDS (10 g/l) was found at a SDS concentration much less than its CMC value (2.33 g/l) in...

Tissue inhibitor of matrix metalloproteinase–2 (TIMP-2) belongs to a small family of endogenous proteins that inhibits a group of enzymes, the matrix metalloproteinases (MMPs). TIMP-2 inhibits endothelial cell proliferation and migration in vitro and angiogenesis in vivo, through MMP-dependent and -independent mechanisms. However, little is known regarding the contribution of these mechanisms to the antitumor effects of TIMP-2. Using a retroviral delivery system, we stably overexpressed TIMP-2 and its mutant Ala+TIMP-2 (devoid of MMP inhibitory activity) in human adenocarcinoma A549 cells. Using real time PCR, and enzyme-linked immunosorbent assay (ELISA), we confirmed enhanced TIMP-2 expression and its MMP inhibitory activity by reverse zymography. In vitro, growth assays suggested that TIMP-2 and Ala+TIMP-2 did not alter basal cell proliferation rates, however, tumor cell migration and invasion were inhibited. In vivo, both TIMP-2 and Ala+TIMP-2 A549 xenografts exhibited reduced growth rate, CD31 immunostaining indicated decreased intratumoral microvascular density, and TUNEL demonstrated enhanced tumor cell apoptosis. Immunoblotting and immunohistochemical analyses of A549 xenograft tissues with either phospho-FAK (Tyr397) or phospho-AKT (Ser473) showed decreased activation in both TIMP-2 and Ala+TIMP-2 tumor cells. We conclude that TIMP-2-mediated inhibition of tumor growth occurs, at least in part, independently of MMP inhibition, and is a consequence of both direct effects of TIMP-2 on tumor cells and modulation of the tumor microenvironment.

The performances of aqueous mixtures of the model nonionic surfactant Triton X-100 (TX100) and chitosan (CS) for the solubilization of the hydrophobic organic compound phenanthrene (PHE) were evaluated by varying mixture compositions. The addition of minute amounts of CS into TX100 solutions above the critical micelle concentration significantly increased PHE solubility. The PHE solubility was maximized at certain optimal concentrations of CS increasing in proportion to the TX100 concentrations, which were 2, 10, and 20 mg/L CS for 5, 10, and 20 g/L TX100, respectively. At each optimal concentration of CS, PHE solubility was increased by 46%, 39%, and 43% for the 5, 10, and 20 g/L TX100 solutions, respectively. The enhanced solubilization of PHE by the addition of CS to TX100 solutions may be attributable to multiple factors, such as an increase of micellar size and hydrophobicity as well as to the formation of variously configured micelle-polymer aggregates.

Effective coagulation and separation of particles in a soil-washed solution is required for a successful soil washing process. The effectiveness of chitosan (CS), a polycationic biodegradable polymer, as a coagulant was compared to polyacrylamide (PAA) and polyaluminium chloride (PAC) for the coagulation of a soil suspension (5 g L −1 ). The effect of surfactants in the coagulation process was investigated using Triton X-100 (TX-100), a nonionic surfactant, and sodium dodecyl sulfate (SDS), an anionic surfactant. CS (5 mg L −1 ) removed 86% and 63% of the suspended soil in the presence of TX-100 (5 g L −1 ) and SDS (5 g L −1 ), respectively, after 30 min at a pH of 6. The results prove that coagulation in the presence of TX-100 is more effective than with SDS. CS was found to be more efficient compared to PAA and PAC under all coagulation conditions. The optimum concentration of CS required for maximum coagulation of soil suspension was 5 mg L −1 . PAA and PAC could not achieve the same degree soil removal as CS even after increasing their concentrations up to 50 mg L −1 . Maximum levels of 50% and 60% soil removal were achieved using PAA (50 mg L −1 ) and PAC (50 mg L −1 ), respectively, after 30 min from a 5 g L −1 suspension containing TX-100 (5 g L −1 ). The soil coagulation process was found to decrease with an increase in the pH of the suspension, and maximum coagulation was achieved with an acidic pH.

Chitosan, a biodegradable compound, is used as an eco-friendly coagulant in water and wastewater treatment to avoid production of the large amounts of sludge using conventional chemical coagulants. Conditioning of chitosan using four different salts (Na2SO4, NaHSO4, (NH4)2SO4, and KHSO4) along with H2SO4 and treatment condition optimization were investigated to enhance coagulating efficiency for bentonite suspension. Chitosan dissolved in acetic acid was used for coagulation of 5 g/l bentonite suspension. The optimum concentration of chitosan required for maximum coagulation of bentonite suspension was 5 mg/l. Among the five additives used for conditioning, NaHSO4, at all concentrations, was found to be the most effective for enhancing the coagulating efficiency of chitosan and it was at its maximum when conditioned by 0.05 mM NaHSO4. NaHSO4 conditioned chitosan showed better coagulating efficiency than unconditioned chitosan at all pHs (3–8) tested in this study. The coagulation of bentonite by chitosan was found to decrease with increase in pH of the suspension. Using 5 mg/l of NaHSO4 conditioned chitosan at pH 6, the removal percentage of bentonite was increased from 76% to 88 % compared to unconditioned chitosan.

Wdpcp, a protein required for both planar cell polarity and ciliogenesis, regulates cell polarity and alignment via direct modulation of the actin cytoskeleton., Planar cell polarity (PCP) regulates cell alignment required for collective cell movement during embryonic development. This requires PCP/PCP effector proteins, some of which also play essential roles in ciliogenesis, highlighting the long-standing question of the role of the cilium in PCP. Wdpcp, a PCP effector, was recently shown to regulate both ciliogenesis and collective cell movement, but the underlying mechanism is unknown. Here we show Wdpcp can regulate PCP by direct modulation of the actin cytoskeleton. These studies were made possible by recovery of a Wdpcp mutant mouse model. Wdpcp-deficient mice exhibit phenotypes reminiscent of Bardet–Biedl/Meckel–Gruber ciliopathy syndromes, including cardiac outflow tract and cochlea defects associated with PCP perturbation. We observed Wdpcp is localized to the transition zone, and in Wdpcp-deficient cells, Sept2, Nphp1, and Mks1 were lost from the transition zone, indicating Wdpcp is required for recruitment of proteins essential for ciliogenesis. Wdpcp is also found in the cytoplasm, where it is localized in the actin cytoskeleton and in focal adhesions. Wdpcp interacts with Sept2 and is colocalized with Sept2 in actin filaments, but in Wdpcp-deficient cells, Sept2 was lost from the actin cytoskeleton, suggesting Wdpcp is required for Sept2 recruitment to actin filaments. Significantly, organization of the actin filaments and focal contacts were markedly changed in Wdpcp-deficient cells. This was associated with decreased membrane ruffling, failure to establish cell polarity, and loss of directional cell migration. These results suggest the PCP defects in Wdpcp mutants are not caused by loss of cilia, but by direct disruption of the actin cytoskeleton. Consistent with this, Wdpcp mutant cochlea has normal kinocilia and yet exhibits PCP defects. Together, these findings provide the first evidence, to our knowledge, that a PCP component required for ciliogenesis can directly modulate the actin cytoskeleton to regulate cell polarity and directional cell migration., Author Summary Cilia are microscopic cell surface hair-like protrusions that can act as antennae to mediate cell signaling. Mutations disrupting ciliogenesis can cause many developmental anomalies associated with syndromes known as “ciliopathies.” Some developmental defects, such as limb polydactyly, arise from disruption of cilia-transduced sonic hedgehog signaling, while other defects, such as aberrant patterning of hair cells in the inner ear, arise from disrupted Wnt signaling resulting in modulation of planar cell polarity (PCP)—a process whereby cells are polarized and aligned. While ciliopathy phenotypes would suggest that cilia are involved in modulating PCP, the mechanistic link between cilia and PCP has been elusive. Our study using a mouse model carrying a mutation in Wdpcp, a gene required for both ciliogenesis and PCP, suggest that Wdpcp modulation of PCP involves interactions with the actin cytoskeleton separate from its function in ciliogenesis. We observe Wdpcp localization in cilia, where it is required for recruitment of proteins essential for ciliogenesis. Wdpcp interacts with Sept2, and is also found in actin filaments, where it regulates actin dynamics essential for PCP. Together, these findings show that PCP regulation by Wdpcp is distinct from its function in ciliogenesis and involves direct modulation of the actin cytoskeleton.