Coral recovery in the central Maldives archipelago since the last major mass-bleaching, in 1998

Increasing frequency and severity of disturbances is causing global degradation of coral reef ecosystems. This study examined temporal changes in live coral cover and coral composition in the central Maldives from 1997 to 2016, encompassing two bleaching events, a tsunami, and an outbreak of Acanthaster planci. We also examined the contemporary size structure for five dominant coral taxa (tabular Acropora, Acropora muricata, Acropora humilis, Pocillopora spp, and massive Porites). Total coral cover increased throughout the study period, with marked increases following the 1998 mass-bleaching. The relative abundance of key genera has changed through time, where Acropora and Pocillopora (which are highly susceptible to bleaching) were under-represented following 1998 mass-bleaching but increased until outbreaks of A. planci in 2015. The contemporary size-structure for all coral taxa was dominated by larger colonies with peaked distributions suggesting that recent disturbances had a disproportionate impact on smaller colonies, or that recruitment is currently limited. This may suggest that coral resilience has been compromised by recent disturbances, and further bleaching (expected in 2016) could lead to highly protracted recovery times. We showed that Maldivian reefs recovered following the 1998 mass-bleaching event, but it took up to a decade, and ongoing disturbances may be eroding reef resilience

Prostate cancer treated with brachytherapy; an exploratory study of dose-dependent biomarkers and quality of life

BACKGROUND: Low-dose-rate permanent prostate brachytherapy (PPB) is an attractive treatment option for patients with localised prostate cancer with excellent outcomes. As standard CT-based post-implant dosimetry often correlates poorly with late treatment-related toxicity, this exploratory (proof of concept) study was conducted to investigate correlations between radiation − induced DNA damage biomarker levels, and acute and late bowel, urinary, and sexual toxicity. METHODS: Twelve patients treated with (125)I PPB monotherapy (145Gy) for prostate cancer were included in this prospective study. Post-implant CT based dosimetry assessed the minimum dose encompassing 90% (D(90%)) of the whole prostate volume (global), sub-regions of the prostate (12 sectors) and the near maximum doses (D(0.1cc), D(2cc)) for the rectum and bladder. Six blood samples were collected from each patient; pre-treatment, 1 h (h), 4 h, 24 h post-implant, at 4 weeks (w) and at 3 months (m). DNA double strand breaks were investigated by staining the blood samples with immunofluorescence antibodies to γH2AX and 53BP1 proteins (γH2AX/53BP1). Patient self-scored quality of life from the Expanded Prostate Cancer Index Composite (EPIC) were obtained at baseline, 1 m, 3 m, 6 m, 9 m, 1 year (y), 2y and 3y post-treatment. Spearman’s correlation coefficients were used to evaluate correlations between temporal changes in γH2AX/53BP1, dose and toxicity. RESULTS: The minimum follow up was 2 years. Population mean prostate D(90%) was 144.6 ± 12.1 Gy and rectal near maximum dose D(0.1cc) = 153.0 ± 30.8 Gy and D(2cc) = 62.7 ± 12.1 Gy and for the bladder D(0.1cc) = 123.1 ± 27.0 Gy and D(2cc) = 70.9 ± 11.9 Gy. Changes in EPIC scores from baseline showed high positive correlation between acute toxicity and late toxicity for both urinary and bowel symptoms. Increased production of γH2AX/53BP1 at 24 h relative to baseline positively correlated with late bowel symptoms. Overall, no correlations were observed between dose metrics (prostate global or sector doses) and γH2AX/53BP1 foci counts. CONCLUSIONS: Our results show that a prompt increase in γH2AX/53BP1foci at 24 h post-implant relative to baseline may be a useful measure to assess elevated risk of late RT − related toxicities for PPB patients. A subsequent investigation recruiting a larger cohort of patients is warranted to verify our findings. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13014-017-0792-1) contains supplementary material, which is available to authorized users

Anodic Aluminum Oxide Membrane-Assisted Fabrication of β-In2S3Nanowires

In this study, β-In2S3nanowires were first synthesized by sulfurizing the pure Indium (In) nanowires in an AAO membrane. As FE-SEM results, β-In2S3nanowires are highly ordered, arranged tightly corresponding to the high porosity of the AAO membrane used. The diameter of the β-In2S3nanowires is about 60 nm with the length of about 6–8 μm. Moreover, the aspect ratio of β-In2S3nanowires is up to 117. An EDS analysis revealed the β-In2S3nanowires with an atomic ratio of nearly S/In = 1.5. X-ray diffraction and corresponding selected area electron diffraction patterns demonstrated that the β-In2S3nanowire is tetragonal polycrystalline. The direct band gap energy (Eg) is 2.40 eV from the optical measurement, and it is reasonable with literature

High rate of subclinical chikungunya virus infection and association of neutralizing antibody with protection in a prospective cohort in the Philippines.

BACKGROUND: Chikungunya virus (CHIKV) is a globally re-emerging arbovirus for which previous studies have indicated the majority of infections result in symptomatic febrile illness. We sought to characterize the proportion of subclinical and symptomatic CHIKV infections in a prospective cohort study in a country with known CHIKV circulation. METHODS/FINDINGS: A prospective longitudinal cohort of subjects ≥6 months old underwent community-based active surveillance for acute febrile illness in Cebu City, Philippines from 2012-13. Subjects with fever history were clinically evaluated at acute, 2, 5, and 8 day visits, and at a 3-week convalescent visit. Blood was collected at the acute and 3-week convalescent visits. Symptomatic CHIKV infections were identified by positive CHIKV PCR in acute blood samples and/or CHIKV IgM/IgG ELISA seroconversion in paired acute/convalescent samples. Enrollment and 12-month blood samples underwent plaque reduction neutralization test (PRNT) using CHIKV attenuated strain 181/clone25. Subclinical CHIKV infections were identified by ≥8-fold rise from a baseline enrollment PRNT titer 50 years old. Baseline CHIKV PRNT titer ≥10 was associated with 100% (95%CI: 46.1, 100.0) protection from symptomatic CHIKV infection. Phylogenetic analysis demonstrated Asian genotype closely related to strains from Asia and the Caribbean. CONCLUSIONS: Subclinical infections accounted for a majority of total CHIKV infections. A positive baseline CHIKV PRNT titer was associated with protection from symptomatic CHIKV infection. These findings have implications for assessing disease burden, understanding virus transmission, and supporting vaccine development

Effect of recombination and binding properties on the performance of dye sensitized solar cells based on propeller shaped triphenylamine dyes with multiple binding groups

Herein we report three novel donor-π-acceptor type dyes TPAA1, TPAA2 and TPAA3, which were investigated for photophysical and electrochemical properties as well as dye-sensitized solar cell performance. These dyes have triphenylamine group at the core of the structure acting as the donor moiety which is radially connected to one, two or three cyanoacrylic acid acceptor groups through phenylethynyl bridges. These dyes can harvest light up to 600 nm as revealed by absorption studies, which is complemented by the IPCE spectra. The propeller shapes of the dyes prevent their aggregation on TiO₂ surface and give better solar cell performance without the need for any co-adsorbent. DSSCs fabricated using TPAA1 gave the best solar cell performance with a short circuit current (J_sc) of 9.96 mA cm⁻², an open circuit voltage (V_oc) of 0.69 V and a fill factor (FF) of 0.73, which correspond to an overall power conversion efficiency of 5.05%. Infrared spectroscopy and computational studies were carried out which gave interesting insights into the mode of dye binding to TiO₂. Lifetime and recombination measurements were carried out using charge extraction and detailed impedance analysis. The Nyquist and Bode plots along with the fitted EIS data reveal that resistance to recombination is higher for TPAA1 in comparison to TPAA2 and TPAA3 leading to better cell performance, which in turn may be attributed to the orientation of the dye molecule on the TiO2 surface

Probing Recombination Mechanism and Realization of Marcus Normal Region Behavior in DSSCs Employing Cobalt Electrolytes and Triphenylamine Dyes

Cobalt based, outer-sphere, one-electron redox shuttles represents an exciting class of alternative electrolyte to be used in dye-sensitized solar cells. The flexibility of redox potential tuning by varying the substituents on peripheral organic ligands renders them the advantage of achieving higher photovoltage. However, higher recombination experienced in these systems by employing diffusion-limited cobalt species serves as a bottleneck which significantly limits attaining higher performance. The focus of the present contribution is to systematically investigate in detail the effect of structural variations and steric hindrance of organic triphenylamine dyes (TPAA4 and TPAA5) which differs in the number and nature of binding groups and peripheral hole accepting units on the recombination reactions and mass transport variations employing two different cobalt electrolytes, [Co₃]^3+/2+ and [Co­(phen)₃]^3+/2+, having variable driving force for recombination. The detailed photovoltaic analysis provides us the information that modification of the architecture of organic dyes plays a decisive role in determining the performance, in particular, employing alternate one-electron outer-sphere redox systems. From our analysis, for both the dyes the charge recombination with the oxidized cobalt species was found to happen in the Marcus normal region which is attributed to the shift in conduction band (CB) that influenced the driving force for recombination. The current observation was quite exciting since the redox systems employed in the present study were previously documented to exhibit Marcus inverted recombination behavior. The impact of structural variations of dyes, change in conduction band, effect of nature of electrolyte species, and its interaction with the semiconductor on the recombination reactions was explored in detail using a range of small and large perturbation techniques