To compare the optical and electrical device characteristics of nano-patterned solar cells, a control group with a planar photoactive layer/back electrode interface is used. We observe that patterned solar cells yield a higher photocurrent output for a length L.
The observation of the effect above 284 nanometers is absent for thinner active layer configurations. A finite-difference time-domain approach to simulating the optical properties of planar and patterned devices reveals enhanced light absorption at patterned electrode interfaces, due to the excitation of propagating surface plasmon and dielectric waveguide modes. Detailed analysis of the external quantum efficiency and voltage-dependent charge extraction in planar and patterned solar cells reveals, however, that the increased photocurrents in the patterned devices are not a product of optical enhancement, but are instead a consequence of enhanced charge carrier extraction efficiency within the space charge limited extraction regime. The findings unequivocally show a correlation between the enhanced charge extraction in patterned solar cells and the periodic surface undulations of the (back) electrode interface.
The online version includes supplementary material, which can be found at the link 101007/s00339-023-06492-6.
A supplementary resource, associated with the online version, is available at 101007/s00339-023-06492-6.
Circular dichroism (CD) in a material results from the differing absorption of left- and right-circularly polarized light. The design of circularly polarized thermal light sources, alongside molecular sensing, relies significantly on this factor for numerous applications. The inherent weakness of CDs in natural materials necessitates the recourse to artificial chiral materials for improved properties. Chiral woodpile structures, arranged in layers, are frequently exploited to augment chiro-optical effects when realized within the contexts of photonic crystals or optical metamaterials. A thorough examination of light scattering from a chiral plasmonic woodpile, structured at the scale of the light's wavelength, reveals that the fundamental evanescent Floquet states are crucial for accurate understanding of the phenomena. Our findings reveal a wide circular polarization bandgap within the complex band structure of various plasmonic woodpile architectures. This bandgap encompasses the optical transparency range of the atmosphere between 3 and 4 micrometers, leading to an average circular dichroism value as high as 90% throughout this spectral span. Our findings could potentially lead to a thermal source capable of producing ultra-broadband circular polarization.
Valvular heart disease, a significant health problem globally, is most often caused by rheumatic heart disease (RHD), disproportionately affecting individuals in low- and middle-income countries. Diagnosing, screening, and managing rheumatic heart disease (RHD) often relies on multiple imaging procedures, including cardiac CT scans, cardiac MRI scans, and three-dimensional echocardiography. In the field of rheumatic heart disease assessment, two-dimensional transthoracic echocardiography continues to be the standard and reliable imaging approach. The 2012 diagnostic criteria for rheumatic heart disease (RHD), put forth by the World Heart Foundation, aimed to standardize the interpretation of imaging studies, though doubts persist about their complexity and reproducibility in practice. Over the intervening period, additional methods have been crafted to strike a balance between simplicity and accuracy. Undeniably, unresolved imaging problems in RHD exist, namely the design of a user-friendly and sensitive screening protocol for identifying individuals affected by RHD. Portable echocardiography offers the possibility of fundamentally altering the way rheumatic heart disease is managed in settings lacking adequate resources, but its function as a screening or diagnostic tool is still under scrutiny. Imaging modalities' dramatic evolution over recent decades has yielded little progress in addressing right-heart disease (RHD) when compared to other structural heart conditions. Cardiac imaging and RHD's current and most up-to-date advancements are the subject of this review.
Interspecies hybridization that leads to polyploidy can trigger immediate post-zygotic isolation, thus giving rise to the saltatory formation of new species. Though polyploidization is a common occurrence in plants, the survival of a new polyploid lineage relies on its capacity to establish a distinct ecological niche, separate and different from those occupied by its ancestral lineages. Our research investigated whether the survival of Rhodiola integrifolia, a North American plant potentially allopolyploid, originating from the hybridization of R. rhodantha and R. rosea, could be attributed to niche divergence. In order to achieve this, we sequenced two low-copy nuclear genes (ncpGS and rpb2) across 42 Rhodiola species, undertaking a phylogenetic analysis to evaluate niche equivalency and similarity. Schoener's D served as the metric for niche overlap. Our phylogenetic investigation revealed that *R. integrifolia* contains alleles inherited from *R. rhodantha* and *R. rosea*. Through the dating analysis of the hybridization event, researchers determined a close approximate time for the origin of R. integrifolia. check details Beringia, 167 million years ago, potentially hosted both R. rosea and R. rhodantha, according to niche modeling, which provides insight into the feasibility of a hybridization event. The ecological niche of R. integrifolia exhibits a divergence from its progenitors, characterized by both a change in the spectrum of resources used and a shift in the ideal environmental conditions. check details These results, when viewed in tandem, solidify the hybrid origins of R. integrifolia, supporting the niche divergence hypothesis for the tetraploid character of this species. Hybrid progeny from lineages with currently disjoint distributions are potentially explained by past periods of climate variability that led to overlapping ranges, as evidenced by our research.
Geographical disparities in biodiversity have long served as a central focus of study in ecology and evolutionary biology. The understanding of how phylogenetic diversity (PD) and phylogenetic beta diversity (PBD) vary among congeneric species with disjunct distributions across eastern Asia and eastern North America (EA-ENA disjuncts), and the influencing factors, remains incomplete. In 11 mixed-species natural forest sites (five in Eastern Asia, and six in Eastern North America), where numerous examples of Eastern Asian-Eastern North American disjunctions are present, we examined the standardized effect size of PD (SES-PD), PBD, and related elements. At the continental level, ENA disjuncts exhibited a significantly higher SES-PD (196) compared to EA disjuncts (-112), despite ENA possessing a smaller number of disjunct species (128) than EA (263). The 11 study sites revealed a pattern of decreasing SES-PD for EA-ENA disjuncts in conjunction with increasing latitude. Regarding the latitudinal diversity gradient of SES-PD, EA sites demonstrated a more pronounced gradient compared to those found in ENA sites. PBD's assessment of unweighted UniFrac distance and phylogenetic community dissimilarity revealed a closer relationship between the two northern EA sites and the six-site ENA group, as opposed to the remaining southern EA sites. Nine of eleven examined sites displayed a neutral community structure, as indicated by their standardized effect size of mean pairwise distances (SES-MPD), which ranged from -196 to 196. A strong correlation, as evidenced by both Pearson's r and structural equation modeling, exists between the SES-PD of the EA-ENA disjuncts and mean divergence time. The SES-PD of EA-ENA disjuncts demonstrated a positive association with temperature-related climatic factors, inversely correlated with mean diversification rate and community structure. check details Our research, informed by phylogenetic and community ecological principles, illuminates the historical divergence of the EA-ENA disjunction and facilitates further research.
Previously, the genus Amana (Liliaceae), nicknamed 'East Asian tulips', encompassed only seven species. This study employed a phylogenomic and integrative taxonomic methodology to determine the existence of two new species, Amana nanyueensis from Central China and A. tianmuensis from East China. Although a densely villous-woolly bulb tunic and two opposite bracts are common to both nanyueensis and Amana edulis, their leaves and anthers are noticeably different. Amana tianmuensis, similar to Amana erythronioides in its possession of three verticillate bracts and yellow anthers, is nonetheless distinguished by its leaf and bulb characteristics. Based on morphology, principal components analysis shows a clear separation among these four species. Studies of plastid CDS phylogenomics underscore the species-level separation of A. nanyueensis and A. tianmuensis and suggest their close evolutionary relationship with A. edulis. A. nanyueensis and A. tianmuensis display a consistent diploid chromosome structure, specifically 24 chromosomes (2n = 2x = 24), according to the cytological results. This is unlike A. edulis, which shows diploid chromosomes (2n = 2x = 24) in northern areas, and tetraploid chromosomes (2n = 4x = 48) in southern regions. Like other Amana species, A. nanyueensis pollen exhibits a single germination groove. In contrast, A. tianmuensis' pollen possesses a sulcus membrane, creating a deceptive impression of multiple grooves. Ecological niche modeling illustrated a separation in niche preferences among A. edulis, A. nanyueensis, and A. tianmuensis.
The scientific names of organisms act as definitive identifiers, characterizing both plants and animals. Employing scientific names correctly is a necessary step for detailed biodiversity research and preservation of records. In this work, we detail the R package 'U.Taxonstand' which offers rapid, high-quality standardization and harmonization of scientific names found within plant and animal species listings.