Broadband enhancement of thermal radiation

CAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOBroadband thermal radiation sources are critical for various applications including spectroscopy and electricity generation. However, due to the difficulty in simultaneously achieving high absorptivity and low thermal mass these sources are inefficient. We show a platform that enables one to obtain enhanced emission by coupling a thermal emitter to an optical cavity. We experimentally demonstrate broadband enhancement of thermal emission between lambda similar to 2 - 4.2 mu m using an inherently poor thermal emitter consisting of tens of nanometers thick SiC film with 10% emissivity (epsilon(S)(iC) similar to 0.1). We measure over twofold enhancement of total emission power over the entire spectral band and threefold enhancement of thermal emission over 3 to 3.4 mu m. Our platform has the potential to enable development of ideal blackbody sources operating at substantially lower heating powers.2712A818A828CAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOSem informaçãoSem informaçãoARPA-E IDEAS program (# DE-AR0000731), support from Brazilian agencies CAPES and FAPESP. Device fabrication & thin-film characterization at Cornell Nano-Scale Facility (NSF, # NNCI-1542081) and Cornell Center for Materials Research (NSF MRSEC, # DMR-1719875)

The taxonomic and functional biogeographies of phytoplankton and zooplankton communities across boreal lakes

Dataset for the study: The taxonomic and functional biogeographies of phytoplankton and zooplankton communities across boreal lakes published in Peer Community in Ecolog

Horizon scan of conservation issues for inland waters in Canada

Horizon scanning is a systematic approach increasingly used to explore emerging trends, issues, opportunities, and threats in conservation. We present the results from one such exercise aimed at identifying emerging issues that could have important scientific, social, technological, and managerial implications for the conservation of inland waters in Canada in the proximate future. We recognized six opportunities and nine challenges, for which we provide research implications and policy options, such that scientists, policy makers, and the Canadian society as a whole can prepare for a potential growth in each of the topic areas we identified. The issues spanned a broad range of topics, from recognizing the opportunities and challenges of community-enabled science and the need to consider the legal rights of nature, to the likely increase of pharmaceuticals in wastewater due to an aging population. These issues represent a first baseline that could help decision makers identify and prioritize efforts while simultaneously stimulate new research avenues. We hope our horizon scan will pave the way for similar exercises related to the conservation of biodiversity in Canada.This project was organized with the support of the Groupe de recherche Interuniversitaire en Limnologie, and the Liber Ero Chair at McGill University. IGE, RB, MC, SJC, AH acknowledge support from the Canada Research Chairs program, and KG, CB and NSG acknowledge funding from the NSERC-funded LakePulse Network. WJS is funded by Arcadia. The authors also thank Sara Pancheri for developing Figure 1a. Finally, we would like to thank Amanda K. Winegardner, who was an active participant in the workshop and provided substantial edits and comments of the manuscript

Co-Evolution of Primate SAMHD1 and Lentivirus Vpx Leads to the Loss of the vpx Gene in HIV-1 Ancestor

Cross-species transmission and adaptation of simian immunodeficiency viruses (SIVs) to humans have given rise to human immunodeficiency viruses (HIVs). HIV type 1 (HIV-1) and type 2 (HIV-2) were derived from SIVs that infected chimpanzee (SIVcpz) and sooty mangabey (SIVsm), respectively. The HIV-1 restriction factor SAMHD1 inhibits HIV-1 infection in human myeloid cells and can be counteracted by the Vpx protein of HIV-2 and the SIVsm lineage. However, HIV-1 and its ancestor SIVcpz do not encode a Vpx protein and HIV-1 has not evolved a mechanism to overcome SAMHD1-mediated restriction. Here we show that the co-evolution of primate SAMHD1 and lentivirus Vpx leads to the loss of the vpx gene in SIVcpz and HIV-1. We found evidence for positive selection of SAMHD1 in orangutan, gibbon, rhesus macaque, and marmoset, but not in human, chimpanzee and gorilla that are natural hosts of Vpx-negative HIV-1, SIVcpz and SIVgor, respectively, indicating that vpx drives the evolution of primate SAMHD1. Ancestral host state reconstruction and temporal dynamic analyses suggest that the most recent common ancestor of SIVrcm, SIVmnd, SIVcpz, SIVgor and HIV-1 was a SIV that had a vpx gene; however, the vpx gene of SIVcpz was lost approximately 3643 to 2969 years ago during the infection of chimpanzees. Thus, HIV-1 could not inherit the lost vpx gene from its ancestor SIVcpz. The lack of Vpx in HIV-1 results in restricted infection in myeloid cells that are important for antiviral immunity, which could contribute to the AIDS pandemic by escaping the immune responses

Differential Effects of Vpr on Single-cycle and Spreading HIV-1 Infections in CD4+ T-cells and Dendritic Cells

The Vpr protein of human immunodeficiency virus type 1 (HIV-1) contributes to viral replication in non-dividing cells, specifically those of the myeloid lineage. However, the effects of Vpr in enhancing HIV-1 infection in dendritic cells have not been extensively investigated. Here, we evaluated the role of Vpr during infection of highly permissive peripheral blood mononuclear cells (PBMCs) and CD4+ T-cells and compared it to that of monocyte-derived dendritic cells (MDDCs), which are less susceptible to HIV-1 infection. Infections of dividing PBMCs and non-dividing MDDCs were carried out with single-cycle and replication-competent HIV-1 encoding intact Vpr or Vpr-defective mutants. In contrast to previous findings, we observed that single-cycle HIV-1 infection of both PBMCs and MDDCs was significantly enhanced in the presence of Vpr when the viral stocks were carefully characterized and titrated. HIV-1 DNA quantification revealed that Vpr only enhanced the reverse transcription and nuclear import processes in single-cycle HIV-1 infected MDDCs, but not in CD4+ T-cells. However, a significant enhancement in HIV-1 gag mRNA expression was observed in both CD4+ T-cells and MDDCs in the presence of Vpr. Furthermore, Vpr complementation into HIV-1 virions did not affect single-cycle viral infection of MDDCs, suggesting that newly synthesized Vpr plays a significant role to facilitate single-cycle HIV-1 infection. Over the course of a spreading infection, Vpr significantly enhanced replication-competent HIV-1 infection in MDDCs, while it modestly promoted viral infection in activated PBMCs. Quantification of viral DNA in replication-competent HIV-1 infected PBMCs and MDDCs revealed similar levels of reverse transcription products, but increased nuclear import in the presence of Vpr independent of the cell types. Taken together, our results suggest that Vpr has differential effects on single-cycle and spreading HIV-1 infections, which are dependent on the permissiveness of the target cell

Contributions of Dopamine-Related Genes and Environmental Factors to Highly Sensitive Personality: A Multi-Step Neuronal System-Level Approach

Traditional behavioral genetic studies (e.g., twin, adoption studies) have shown that human personality has moderate to high heritability, but recent molecular behavioral genetic studies have failed to identify quantitative trait loci (QTL) with consistent effects. The current study adopted a multi-step approach (ANOVA followed by multiple regression and permutation) to assess the cumulative effects of multiple QTLs. Using a system-level (dopamine system) genetic approach, we investigated a personality trait deeply rooted in the nervous system (the Highly Sensitive Personality, HSP). 480 healthy Chinese college students were given the HSP scale and genotyped for 98 representative polymorphisms in all major dopamine neurotransmitter genes. In addition, two environment factors (stressful life events and parental warmth) that have been implicated for their contributions to personality development were included to investigate their relative contributions as compared to genetic factors. In Step 1, using ANOVA, we identified 10 polymorphisms that made statistically significant contributions to HSP. In Step 2, these polymorphism's main effects and interactions were assessed using multiple regression. This model accounted for 15% of the variance of HSP (p<0.001). Recent stressful life events accounted for an additional 2% of the variance. Finally, permutation analyses ascertained the probability of obtaining these findings by chance to be very low, p ranging from 0.001 to 0.006. Dividing these loci by the subsystems of dopamine synthesis, degradation/transport, receptor and modulation, we found that the modulation and receptor subsystems made the most significant contribution to HSP. The results of this study demonstrate the utility of a multi-step neuronal system-level approach in assessing genetic contributions to individual differences in human behavior. It can potentially bridge the gap between the high heritability estimates based on traditional behavioral genetics and the lack of reproducible genetic effects observed currently from molecular genetic studies