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Using cyclic voltammetry under illumination, we recently demonstrated that CdS quantum dots (QDs) form charge donor states that live for at least several minutes after illumination ends, â¼12 orders of magnitude longer than expected for free carriers. This time scale suggests that the conventionally accepted mechanism of charge transfer, wherein charges directly transfer to an acceptor following exciton dissociation, cannot be complete. Because of these long time scales, this unconventional pathway is not readily observed using time-resolved spectroscopy to probe charge transfer dynamics. Here, we investigated the chemical nature of these charge donor states using cyclic voltammetry under illumination coupled with NMR spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and optical spectroscopy. Our data reveal that charges are stored locally rather than as free carriers, and the number of charges stored is dependent on the QD surface ligation and stoichiometry. Altogether, our results confirm that electrons are stored at ligated surface Cd, these sites are competent charge donors, and this storage is charge balanced by X-type ligand desorption. We found that charge storage occurs in every QD system studied, including CdS, CdSe, and InP capped with carboxylate and phosphonate ligands.
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Glossogobius giuris was originally described as Gobius giuris from the Ganges River, India. However, based on the uncertainty of its type locality and its apparent widespread distribution, a comprehensive study is being carried out to define the correct taxonomic status of this taxon. The South African population of the Glossogobius from St. Lucia Lake, KwaZulu-Natal was described as Glossogobius tenuiformis by Fowler in 1934. It has usually been considered as Glossogobius giuris but Hoese and Hammer indicated that it was a distinct species (2021: 83). Here, based on morphological characters and a molecular data set, we redescribe Glossogobius tenuiformis and assign the Oman populations of Glossogobius to this species. Glossogobius tenuiformis is distinguished from G. giuris by the absence or very short (and often only a few papillae long) sensory papilla line 6; presence of single rows of the sensory papillae in each cheek line, 1216 pre-dorsal scale counts, and 1+1+911, usually 1+1+10, gill rakers on outer face of first arch. Glossogobius tenuiformis is also distinguished by molecular characters. Glossogobius tenuiformis shows 16% genetic distance with other members of this species complex, that includes G. laticeps from Vietnam, Bangladesh and China, G. giuris from South Africa and India and giuris C from India, Myanmar, Nepal, Bangladesh and Vietnam, and the highest genetic distance (24%) with G. circumspectus.
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Perciformes , Animales , Peces/anatomía & histología , Branquias , Omán , SudáfricaRESUMEN
The tropical Indo-west Pacific gobiid fish genus Aulopareia Bleeker is reviewed, with all recognised species redescribed herein, apart from one uncertain species. Additionally, a new species from Kuwait is described (A. vadosa n. sp.). Of the 10 nominal species names usually assigned to this genus, only three appear to be valid Aulopareia (A. koumansi, A. ocellata and A. unicolor). From descriptions and illustrations, Acentrogobius microps Chu and Wu appears to be an Aulopareia but no material was available for study. The species that has been variously named as Acentrogobius cyanomos, Aulopareia cyanomos or Aulopareia spilopterus is redescribed. The status of two other species that may be related is also discussed: Gobius cyanoclavis Cantor and Gobius phaiomelas Bleeker. Aulopareia has been noted as being related to Parachaeturichthys.
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Perciformes , Animales , Peces , KuwaitRESUMEN
This tutorial review presents our perspective on designing organic molecules for the functionalization of inorganic nanomaterial surfaces, through the model of an "anchor-functionality" paradigm. This "anchor-functionality" paradigm is a streamlined design strategy developed from a comprehensive range of materials (e.g., lead halide perovskites, II-VI semiconductors, III-V semiconductors, metal oxides, diamonds, carbon dots, silicon, etc.) and applications (e.g., light-emitting diodes, photovoltaics, lasers, photonic cavities, photocatalysis, fluorescence imaging, photo dynamic therapy, drug delivery, etc.). The structure of this organic interface modifier comprises two key components: anchor groups binding to inorganic surfaces and functional groups that optimize their performance in specific applications. To help readers better understand and utilize this approach, the roles of different anchor groups and different functional groups are discussed and explained through their interactions with inorganic materials and external environments.
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Nanoestructuras , Semiconductores , Rayos Láser , SilicioRESUMEN
The tridentigerine genus Pseudogobius is widespread, from temperate to tropical areas of the Indo-west Pacific. A morphological review of the genus was carried out, with the initial focus on South-east Asian and Australian species. There are about 21 nominal species in the genus; however, the type specimens for some nominal species are missing. Our work recognises 15 valid species so far, including seven new species, which are described herein: P. aquilonius n. sp., P. cinctus n. sp., P. eos n. sp., P. hoesei n. sp., P. jeffi n. sp., P. rhizophora n. sp. and P. verticalis n. sp. We also conclude that P. poicilosoma (Bleeker, 1849) is the senior synonym of P. javanicus (Bleeker, 1856). Pseudogobius poicilosoma, P. gastrospilos (Bleeker, 1853) and P. javanicus are accepted here as conspecific, although the types are in poor condition (note that all three names were given to specimens collected within close proximity to each other in coastal Java, Indonesia). A key to valid species is presented. The revision benefited from an adaptive feedback loop with companion genetic analyses, with the most comprehensive data available for the Australian region. Broader preliminary genetic data suggest the potential for recognition of additional cryptic species, with the current study providing a platform for future systematic work. Pseudogobius are a prominent part of estuarine biodiversity in the Indo-west Pacific, and this study helps to highlight the need to better understand the taxonomy and conservation requirements of cryptobenthic fishes.
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Perciformes , Animales , Asia Sudoriental , Australia , Perciformes/anatomía & histología , Perciformes/clasificación , Especificidad de la EspecieRESUMEN
This manuscript details the development of the nickel-catalyzed arylation of oxazoles and benzoxazoles with aryl halides. A series of aryl, heteroaryl, and druglike electrophiles relevant to pharmaceutical applications were surveyed. The desired arylated products were obtained in synthetically useful yields using electronically and structurally varied aryl halides. The use of microscale high-throughput experimentation was essential for both the rapid identification of optimal reaction parameters and the investigation of the aryl halide scope.
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In 2015, Pezold and Larson published a revision of the gobiid genus Oxyurichthys, and made an error in their use of the name O. uronema (Weber) for one of the species. The reasons for this would make a fine example of one of Evenhuis' taxonomic impediments to nirvana (2007). Pezold and Larson first considered collaborating on this work in 1983, but this did not happen until nearly a decade later. Intensive work began in 1996; by then Larson had examined syntypes of both species in 1988 and determined that Gobius uronema Weber, 1909, was the same species as Gobius longicauda Steindachner, 1893.
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Perciformes/clasificación , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Femenino , Masculino , Perciformes/anatomía & histología , Perciformes/crecimiento & desarrollo , Terminología como AsuntoRESUMEN
The widespread tropical gobionelline fish genus Oxyurichthys is monophyletic due to its species sharing two characters considered derived within the Stenogobius Group of the Gobionellinae (Gobioidei: Gobiidae), a transversely broadened (spatulate) third neural spine that is usually bifid, and no preopercular cephalic lateralis canal. It is most closely related to Oligolepis, also of the Indo-west Pacific, and Ctenogobius, an Atlantic-eastern Pacific genus. Sixteen valid species of Oxyurichthys are redescribed and illustrated and four new species are described, O. limophilus from the western Indian Ocean, O. rapa from French Polynesia, and O. chinensis and O. zeta from the western Pacific. Nineteen species share two additional synapomorphies, a rounded fleshy tongue and a palatine lacking an elongate posterior strut, and form the sister group to the plesiomorphous Oxyurichthys keiensis, known from South Africa and Madagascar. One species, O. stigmalophius, occurs in the western Atlantic. There are no records of this genus from the continental eastern Pacific or the eastern Atlantic. Previous accounts from the Gulf of Guinea region of West Africa are references to Gobionellus occidentalis. Many Oxyurichthys species are limited to shallow estuarine and coastal waters with bottom substrates of silt or other fine sediments, but several are known from depths exceeding 10 m and are often collected by trawling.
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Peces/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Ecosistema , Femenino , Peces/anatomía & histología , Peces/crecimiento & desarrollo , Masculino , Tamaño de los ÓrganosRESUMEN
There are 1474 fish species now known from the Northern Territory, in 195 families, with a number of these species still undescribed. The 1474 species include 120 new records for the NT and three for Australia, while nine non-native species exist as small feral populations.The most speciose family is the Gobiidae (gobies), with 150 recognised species, and is the main fish group inhabiting coral reef and mangrove areas. The fish fauna of the Northern Territory occupies several biogeographical regions, which include the internal river drainages of Australia and the Sahul Shelf adjoining New Guinea and Indonesia. The Northern Territory's fish fauna most closely resembles that of north-western Western Australia, and many species are shared with this region. Among the Northern Territory's fish fauna are 55 species considered to be threatened under various listings (ASFB, EPBC), with the poor state of knowledge of the NT's fish populations and their true distributions hindering assessment. Many sampling gaps remain and the basic biology of most species is unknown.
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Distribución Animal , Peces/fisiología , Animales , Biodiversidad , Peces/clasificación , Northern TerritoryRESUMEN
A new species of the eyeless eleotrid genus Milyeringa is described from wells sunk on Barrow Island, Western Australia. Milyeringa justitia n. sp. is the third species of the genus to be named. Morphological data and cytochrome c oxidase subunit I (COI) DNA sequence data from a wide sample of localities at which the genus occurs was used to evaluate relationships and species limits. Milyeringa veritas is redescribed, and M. brooksi is synonymised with M. veritas. The unique form and ecology of these fishes, plus the threats to their survival, warrants immediate and continuing attention in management.
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Peces/clasificación , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Cuevas , Proteínas de Peces/genética , Peces/anatomía & histología , Peces/genética , Peces/crecimiento & desarrollo , Datos de Secuencia Molecular , Filogenia , Australia OccidentalRESUMEN
BACKGROUND: Indo-Pacific high island streams experience extreme hydrological variation, and are characterised by freshwater fish species with an amphidromous life history. Amphidromy is a likely adaptation for colonisation of island streams following stochastic events that lead to local extirpation. In the Wet Tropics of north-eastern Australia, steep coastal mountain streams share similar physical characteristics to island systems. These streams are poorly surveyed, but may provide suitable habitat for amphidromous species. However, due to their ephemeral nature, common non-diadromous freshwater species of continental Australia are unlikely to persist. Consequently, we hypothesise that coastal Wet Tropics streams are faunally more similar, to distant Pacific island communities, than to nearby faunas of large continental rivers. METHODS/PRINCIPAL FINDINGS: Surveys of coastal Wet Tropics streams recorded 26 species, 10 of which are first records for Australia, with three species undescribed. This fish community is unique in an Australian context in that it contains mostly amphidromous species, including sicydiine gobies of the genera Sicyopterus, Sicyopus, Smilosicyopus and Stiphodon. Species presence/absence data of coastal Wet Tropics streams were compared to both Wet Tropics river networks and Pacific island faunas. ANOSIM indicated the fish fauna of north-eastern Australian coastal streams were more similar to distant Pacific islands (Râ=â0.76), than to nearby continental rivers (Râ=â0.98). MAIN CONCLUSIONS/SIGNIFICANCE: Coastal Wet Tropics streams are faunally more similar to distant Pacific islands (79% of species shared), than to nearby continental fauna due to two factors. First, coastal Wet Tropics streams lack many non-diadromous freshwater fish which are common in nearby large rivers. Second, many amphidromous species found in coastal Wet Tropics streams and Indo-Pacific islands remain absent from large rivers of the Wet Tropics. The evolutionary and conservation significance of this newly discovered Australian fauna requires clarification in the context of the wider amphidromous fish community of the Pacific.
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Peces/clasificación , Animales , Australia , Biodiversidad , Islas del PacíficoRESUMEN
A new species of mudskipper (Gobiidae: Oxudercinae) from northern Australia is described. This species was previously misidentified as P. takita [corrected] Eggert, 1935 . Periophthalmus takita sp. nov. can be distinguished from its congeners by the following suite of characters: modally VIII spines in the first dorsal fin; second dorsal and anal fins with I, 11-12 rays; shape and color pattern of the first and second dorsal fins; and the extent of fusion between the two innermost rays of the pelvic fin. A re-diagnosis of P. takita [corrected] is provided, as well as a revised key to the genus Periophthalmus .