Genetic and behavioural factors affecting interpopulation colour pattern variation in two congeneric chameleon species.

We conducted a study on interpopulation variation of colour patterns in two congeneric chameleon species, which have an analogous life history. Both species are able to rapidly change colour pattern, and their context-dependent colour patterns often vary across a wide geographical range. Specifically, we tested four hypotheses that can explain the observed interpopulation variation of colour patterns by a series of behavioural field trials where the colour patterns of individuals were recorded and later analysed by a deep neural network algorithm. We used redundancy analysis to relate genetic, spectral and behavioural predictors to interpopulation colour pattern distance. Our results showed that both isolation by distance (IBD) and alternative mating tactics were significant predictors for interpopulation colour pattern variation in Chamaeleo chamaeleon males. By contrast, in Chamaeleo dilepis, the interpopulation colour pattern variation was largely explained by IBD, and evidence for alternative mating tactics was absent. In both chameleon species, the environmental colours showed no evidence of influencing chameleon interpopulation colour pattern variation, regardless of sex or behavioural context. This contrasting finding suggests that interpopulation context-dependent colour pattern variations in each species are maintained under a different set of selective pressures or circumstances.

Short- and mid-term changes in CORVIS ST parameters in successful, adult orthokeratology patients.

CLINICAL RELEVANCE: The changes in various biomechanical and tomographic characteristics of the cornea associated with orthokeratology may allow us to identify potential mid- and long-term structural alterations, resulting in a better understanding of the governing mechanisms of this procedure and in its optimisation. BACKGROUND: The study aimed at describing short and mid-term changes in CORVIS ST® parameters and indices in orthokeratology (ortho-k), and their diurnal variations. METHODS: A prospective observational study was designed in which several CORVIS ST® parameters of 75 new adult participants successfully fitted with overnight ortho-k Seefree® (Conóptica - Hecht Contactlinsen) contact lenses were explored. Measurements were conducted in baseline (BL) conditions and in the morning and evening at the one-night (1 NM/1NT), one-week (1WM/1 WT) and 3-month (3 MM/3MT) follow-up visits. RESULTS: Statistically significant differences were found in DARatio_2 mm, IntRad, ARTh, CBI and TBI following overnight ortho-k, when compared with BL values, with most values reaching stability at 1WM or reverting to BL values at 3 MM. The ARTh and CBI parameters showed some of the most significant temporal variations (both p < 0.001), probably reflecting the encountered differences in central corneal thickness between BL and 1WM (p = 0.010) and between BL and 3 MM (p = 0.016). In general, corneal rigidity was higher in the morning at all follow-up visits, and decreased during the day. No statistically significant changes in adjusted intraocular pressure values were found. CONCLUSION: Ortho-k in adults may be considered a safe procedure in terms of short and mid-term changes in CORVIS ST® parameters. The observed alterations in most of the parameters provided by the Corvis ST® probably responded to the well-described changes in corneal pachymetry and tomography, rather than to actual alterations in corneal rigidity.

New insights on patterns of genetic admixture and phylogeographic history in Iberian high mountain populations of midwife toads.

Multiple Quaternary glacial refugia in the Iberian Peninsula, commonly known as "refugia within refugia", allowed diverging populations to come into contact and admix, potentially boosting substantial mito-nuclear discordances. In this study, we employ a comprehensive set of mitochondrial and nuclear markers to shed light onto the drivers of geographical differentiation in Iberian high mountain populations of the midwife toads Alytes obstetricans and A. almogavarii from the Pyrenees, Picos de Europa and Guadarrama Mountains. In the three analysed mountain regions, we detected evidence of extensive mito-nuclear discordances and/or admixture between taxa. Clustering analyses identified three major divergent lineages in the Pyrenees (corresponding to the eastern, central and central-western Pyrenees), which possibly recurrently expanded and admixed during the succession of glacial-interglacial periods that characterised the Late Pleistocene, and that currently follow a ring-shaped diversification pattern. On the other hand, populations from the Picos de Europa mountains (NW Iberian Peninsula) showed a mitochondrial affinity to central-western Pyrenean populations and a nuclear affinity to populations from the central Iberian Peninsula, suggesting a likely admixed origin for Picos de Europa populations. Finally, populations from the Guadarrama Mountain Range (central Iberian Peninsula) were depleted of genetic diversity, possibly as a consequence of a recent epidemic of chytridiomycosis. This work highlights the complex evolutionary history that shaped the current genetic composition of high mountain populations, and underscores the importance of using a multilocus approach to better infer the dynamics of population divergence.

Does hotel management matter to overcoming the COVID-19 crisis? The Spanish case.

This paper analyses the influence that the initial actions and strategies pursued by hotel managers have on the recovery of occupancy after a crisis such as the COVID-19 pandemic. To do this, a specific survey is carried out on managers of Spanish hotels. The main findings show that labour actions, especially plans for temporary employment regulations, innovation and differentiation strategies, reorientation to closer markets and obtaining information from official sources as a guarantee of their certainty, are the measures that have a greater impact on the possibilities of recovering hotel activity. In addition, government measures that contribute to the improvement of the financial situation of firms can also play a relevant role in hotel recovery.

Phylogenomic inference of species and subspecies diversity in the Palearctic salamander genus Salamandra.

The salamander genus Salamandra is widespread across Europe, North Africa, and the Near East and is renowned for its conspicuous and polymorphic colouration and diversity of reproductive modes. The phylogenetic relationships within the genus, and especially in the highly polymorphic species S. salamandra, have been very challenging to elucidate, leaving its real evolutionary history and classification at species and subspecies levels a topic of debate and contention. However, the distribution of diversity and species delimitation within the genus are critically important for identifying evolutionarily significant units for conservation and management, especially in light of threats posed by the pathogenic chytrid fungus Batrachochytrium salamandrivorans that is causing massive declines of S. salamandra populations in central Europe. Here, we conducted a phylogenomic analysis from across the taxonomic and geographic breadth of the genus Salamandra in its entire range. Bayesian, maximum likelihood and network-based phylogenetic analyses of up to 4905 ddRADseq-loci (294,300 nucleotides of sequence) supported the distinctiveness of all currently recognised species (Salamandra algira, S. atra, S. corsica, S. infraimmaculata, S. lanzai, and S. salamandra), and all five species for which we have multiple exemplars were confirmed as monophyletic. Within S. salamandra, two main clades can be distinguished: one clade with the Apenninic subspecies S. s. gigliolii nested within the Iberian S. s. bernardezi/fastuosa; and a second clade comprising all other Iberian, Central and East European subspecies. Our analyses revealed that some of the currently recognized subspecies of S. salamandra are paraphyletic and may require taxonomic revision, with the Central- and Eastern-European subspecies all being poorly differentiated at the analysed genomic markers. Salamandra s. longirostris - sometimes considered a separate species - was nested within S. salamandra, consistent with its subspecies status. The relationships identified within and between Salamandra species provide valuable context for future systematic and biogeographic studies, and help elucidate critical evolutionary units for conservation and taxonomy.

First report of Myxobolus (Cnidaria: Myxozoa) spores in human feces in Brazil / Primeiro relato de esporos de Myxobolus (Cnidaria: Myxozoa) em fezes humanas no Brasil

Most species of Myxobolus (Cnidaria: Myxozoa) infect freshwater and marine fish, and cause sporozoosis. Passage of myxozoan parasites into human feces has been described occasionally. We examined fecal samples from 97 dwellers of a riverine community in Amazonas State (Brazil), which revealed Myxobolus sp. in 13 (13%) samples. The discovery probably does not represent true parasitism as the myxospores - most likely ingested through the consumption of infected fish - were eliminated unchanged after passing through the gastrointestinal tract. This discovery represents the first report of this myxosporean in human fecal samples in Brazil. (AU)

A maioria das espécies de Myxobolus (Cnidaria: Myxozoa) infecta principalmente peixes de água doce e marinhos, nos quais produz esporozoose. A passagem de parasitos mixozoários em fezes humanas tem sido ocasionalmente descrita. Nós examinamos amostras fecais de 97 moradores de uma comunidade ribeirinha no estado do Amazonas e identificamos Myxobolus sp. em 13 (13%) delas. O achado provavelmente não representa um parasitismo verdadeiro, uma vez que os mixosporos − mais provavelmente ingeridos ao consumir peixes infectados − foram eliminados inalterados após a passagem pelo trato gastrointestinal. O achado representa o primeiro relato deste mixosporídeo em amostras fecais humanas no Brasil.(AU)

Effect of Distance on Photoluminescence Quenching and Proximity-Induced Spin-Orbit Coupling in Graphene/WSe2 Heterostructures.

Spin-orbit coupling (SOC) in graphene can be greatly enhanced by proximity coupling it to transition metal dichalcogenides (TMDs) such as WSe2. We find that the strength of the acquired SOC in graphene depends on the stacking order of the heterostructures when using hexagonal boron nitride ( h-BN) as the capping layer, i.e., SiO2/graphene/WSe2/ h-BN exhibiting stronger SOC than SiO2/WSe2/graphene/ h-BN. We utilize photoluminescence (PL) as an indicator to characterize the interaction between graphene and monolayer WSe2 grown by chemical vapor deposition. We observe much stronger PL quenching in the SiO2/graphene/WSe2/ h-BN stack than in the SiO2/WSe2/graphene/ h-BN stack and, correspondingly, a much larger weak antilocalization (WAL) effect or stronger induced SOC in the former than in the latter. We attribute these two effects to the interlayer distance between graphene and WSe2, which depends on whether graphene is in immediate contact with h-BN. Our observations and hypothesis are further supported by first-principles calculations, which reveal a clear difference in the interlayer distance between graphene and WSe2 in these two stacks.

First report of Euryhelmis parasites (Trematoda, Heterophyidae) in Africa: conservation implications for endemic amphibians.

In this study, we report, through molecular identification, the first African records of a digenean trematode parasite of the genus Euryhelmis. We recovered metacercariae encysted in an anuran, the endemic Moroccan painted frog (Discoglossus scovazzi), and a vulnerable caudate, the North African fire salamander (Salamandra algira), from four localities in North Africa (Morocco). Our records go back to the past century and have been confirmed in successive fieldwork seasons thereafter. Metacercarial stages of these parasites require amphibians as the last intermediate host, but the exact identity of the primary hosts and predators of the infected animals in Africa remain unknown. Our searches with basic local alignment search tool (BLAST) from Genbank revealed that hosts were infected by parasites of Euryhelmis costaricensis, which showed almost the same genetic identity (with only one substitution) to previous reports from Costa Rica and Japan, suggesting a recent introduction in Morocco. We proceed to discuss the likely role of introduced mustelids as the potential definitive hosts of trematode adults. Under this assumption, we conclude that the infestation of Discoglossus scovazzi and Salamandra algira might pose a risk to these threatened species.

Neisseria meningitidis disease-associated clones in Amazonas State, Brazil.

BACKGROUND: The aim of this study is to describe the molecular epidemiology of Neisseria meningitidis invasive disease before the introduction of serogroup C conjugate vaccine in Amazonas State in 2010. METHODS: Meningococcal disease reported cases were investigated in Amazonas State during the period 2000-2010. N. meningitidis isolates (n = 196) recovered from patients were genotyped by multilocus sequence typing (MLST) and sequencing of porB, porA, fetA, fHbp and penA. Antimicrobial susceptibility was determined using E-test. RESULTS: In the study period, 948 cases were reported; the incidence was 2.8 for the entire state and 4.8 per 100,000 in the capital of Manaus. Most meningococcal disease was caused by N. meningitidis belonging to ST-32 (72%; 141/196) or ST-103 (21%; 41/196) clonal complexes. Capsular switching (B→C) was suggested within clonal complex (cc) 32. There were 6 (3%; 6/196) strains with intermediate susceptibility to penicillin and a single strain was resistant to rifampicin. Since 2007, serogroup C strains belonging to the cc103 have predominated and case-fatality has increased. CONCLUSION: We demonstrate a high rate of meningococcal disease in Amazonas State, where, like other parts of Brazil, serogroup C replaced serogroup B during 2000s. These data serve as a baseline to measure impact of serogroup C conjugate vaccine introduction in 2010. This study emphasizes the need for enhanced surveillance to monitor changes in meningococcal disease trends following the introduction of meningococcal vaccines.

Invasive Haemophilus influenzae disease in the vaccine era in Rio de Janeiro, Brazil

BACKGROUND Haemophilus influenzae (Hi) serotype b (Hib) conjugate vaccine was incorporated into the infant immunisation schedule in Brazil in 1999, where Hib was one of the major etiologic sources of community-acquired bacterial meningitis. OBJECTIVES The purpose of this study is to describe the molecular epidemiology of invasive Hi disease in Rio de Janeiro state, Brazil, before and after vaccine introduction. METHODS Surveillance data from 1986 to 2014 were analysed. Hi isolates recovered from cerebrospinal fluid (CSF) or blood from 1993 to 2014 were serotyped by slide agglutination, genotyped by multilocus sequence typing (MLST), and the capsule type evaluation, differentiation of serologically non-typeable isolates, and characterisation of the capsule (cap) locus was done by polymerase chain reaction. Antimicrobial susceptibility testing was performed using E-test. FINDINGS From 1986 to 1999 and from 2000 to 2014, 2580 and 197 (42% without serotype information) confirmed cases were reported, respectively. The case fatality rate was 17% and did not correlate with the strain. Hib and b- variant isolates belonged to ST-6, whereas serotype a isolates belonged to the ST-23 clonal complex. Serotype a appeared to emerge during the 2000s. Non-encapsulated isolates were non-clonal and distinct from the encapsulated isolates. Ampicillin-resistant isolates were either of serotype b or were non-encapsulated, and all of them were β-lactamase-positive but amoxicillin-clavulanic acid susceptible. MAIN CONCLUSIONS Although Hi meningitis became a relatively rare disease in Rio de Janeiro after the introduction of the Hib conjugate vaccine, the isolates recovered from patients have become more diverse. These results indicate the need to implement an enhanced surveillance system to continue monitoring the impact of the Hib conjugate vaccine.

Invasive Haemophilus influenzae disease in the vaccine era in Rio de Janeiro, Brazil.

BACKGROUND: Haemophilus influenzae (Hi) serotype b (Hib) conjugate vaccine was incorporated into the infant immunisation schedule in Brazil in 1999, where Hib was one of the major etiologic sources of community-acquired bacterial meningitis. OBJECTIVES: The purpose of this study is to describe the molecular epidemiology of invasive Hi disease in Rio de Janeiro state, Brazil, before and after vaccine introduction. METHODS: Surveillance data from 1986 to 2014 were analysed. Hi isolates recovered from cerebrospinal fluid (CSF) or blood from 1993 to 2014 were serotyped by slide agglutination, genotyped by multilocus sequence typing (MLST), and the capsule type evaluation, differentiation of serologically non-typeable isolates, and characterisation of the capsule (cap) locus was done by polymerase chain reaction. Antimicrobial susceptibility testing was performed using E-test. FINDINGS: From 1986 to 1999 and from 2000 to 2014, 2580 and 197 (42% without serotype information) confirmed cases were reported, respectively. The case fatality rate was 17% and did not correlate with the strain. Hib and b- variant isolates belonged to ST-6, whereas serotype a isolates belonged to the ST-23 clonal complex. Serotype a appeared to emerge during the 2000s. Non-encapsulated isolates were non-clonal and distinct from the encapsulated isolates. Ampicillin-resistant isolates were either of serotype b or were non-encapsulated, and all of them were ß-lactamase-positive but amoxicillin-clavulanic acid susceptible. MAIN CONCLUSIONS: Although Hi meningitis became a relatively rare disease in Rio de Janeiro after the introduction of the Hib conjugate vaccine, the isolates recovered from patients have become more diverse. These results indicate the need to implement an enhanced surveillance system to continue monitoring the impact of the Hib conjugate vaccine.

Scalable fabrication of a hybrid field-effect and acousto-electric device by direct growth of monolayer MoS2/LiNbO3.

Lithium niobate is the archetypical ferroelectric material and the substrate of choice for numerous applications including surface acoustic wave radio frequencies devices and integrated optics. It offers a unique combination of substantial piezoelectric and birefringent properties, yet its lack of optical activity and semiconducting transport hamper application in optoelectronics. Here we fabricate and characterize a hybrid MoS2/LiNbO3 acousto-electric device via a scalable route that uses millimetre-scale direct chemical vapour deposition of MoS2 followed by lithographic definition of a field-effect transistor structure on top. The prototypical device exhibits electrical characteristics competitive with MoS2 devices on silicon. Surface acoustic waves excited on the substrate can manipulate and probe the electrical transport in the monolayer device in a contact-free manner. We realize both a sound-driven battery and an acoustic photodetector. Our findings open directions to non-invasive investigation of electrical properties of monolayer films.

Toward Ferroelectric Control of Monolayer MoS2.

The chemical vapor deposition (CVD) of molybdenum disulfide (MoS2) single-layer films onto periodically poled lithium niobate is possible while maintaining the substrate polarization pattern. The MoS2 growth exhibits a preference for the ferroelectric domains polarized "up" with respect to the surface so that the MoS2 film may be templated by the substrate ferroelectric polarization pattern without the need for further lithography. MoS2 monolayers preserve the surface polarization of the "up" domains, while slightly quenching the surface polarization on the "down" domains as revealed by piezoresponse force microscopy. Electrical transport measurements suggest changes in the dominant carrier for CVD MoS2 under application of an external voltage, depending on the domain orientation of the ferroelectric substrate. Such sensitivity to ferroelectric substrate polarization opens the possibility for ferroelectric nonvolatile gating of transition metal dichalcogenides in scalable devices fabricated free of exfoliation and transfer.

Superlinear composition-dependent photocurrent in CVD-grown monolayer MoS2(1-x)Se2x alloy devices.

Transition metal dichalcogenides (TMDs) have emerged as a new class of two-dimensional materials that are promising for electronics and photonics. To date, optoelectronic measurements in these materials have shown the conventional behavior expected from photoconductors such as a linear or sublinear dependence of the photocurrent on light intensity. Here, we report the observation of a new regime of operation where the photocurrent depends superlinearly on light intensity. We use spatially resolved photocurrent measurements on devices consisting of CVD-grown monolayers of TMD alloys spanning MoS2 to MoSe2 to show the photoconductive nature of the photoresponse, with the photocurrent dominated by recombination and field-induced carrier separation in the channel. Time-dependent photoconductivity measurements show the presence of persistent photoconductivity for the S-rich alloys, while photocurrent measurements at fixed wavelength for devices of different alloy compositions show a systematic decrease of the responsivity with increasing Se content associated with increased linearity of the current-voltage characteristics. A model based on the presence of different types of recombination centers is presented to explain the origin of the superlinear dependence on light intensity, which emerges when the nonequilibrium occupancy of initially empty fast recombination centers becomes comparable to that of slow recombination centers.

Postgrowth tuning of the bandgap of single-layer molybdenum disulfide films by sulfur/selenium exchange.

We demonstrate bandgap tuning of a single-layer MoS2 film on SiO2/Si via substitution of its sulfur atoms by selenium through a process of gentle sputtering, exposure to a selenium precursor, and annealing. We characterize the substitution process both for S/S and S/Se replacement. Photoluminescence and, in the latter case, X-ray photoelectron spectroscopy provide direct evidence of optical band gap shift and selenium incorporation, respectively. We discuss our experimental observations, including the limit of the achievable bandgap shift, in terms of the role of stress in the film as elucidated by computational studies, based on density functional theory. The resultant films are stable in vacuum, but deteriorate under optical excitation in air.

2-dimensional transition metal dichalcogenides with tunable direct band gaps: MoS2(1-x) Se2x monolayers.

MoS2(1-x) Se2x single-layer films are prepared using a mixture of organic selenium and sulfur precursors as well as a solid molybdenum source. The direct bandgaps are found to scale nearly linearly with composition in the range of 1.87 eV (pure single-layer MoS2 ) to 1.55 eV (pure single-layer MoSe2 ) permitting straightforward bandgap engineering.

Three outbreak-causing Neisseria meningitidis serogroup C clones, Brazil(1.).

During 2003-2012, 8 clusters of meningococcal disease were identified in Rio de Janeiro State, Brazil, all caused by serogroup C Neisseria meningitidis. The isolates were assigned to 3 clonal complexes (cc): cc11, cc32, and cc103. These hyperinvasive disease lineages were associated with endemic disease, outbreaks, and high case-fatality rates.