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"Soares, A."
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Scalar field and deflection of light under the effects of topologically charged Ellis–Bronnikov-type wormhole spacetime
We have analyzed the effects of a simple wormhole, known as the Ellis–Bronnikov-type wormhole, on a scalar field, where, analytically, we determine solutions of bound states and show that the relativistic energy profile of this scalar field is drastically influenced by the topology of space-time characterized by the presence of a global monopole. Before this analysis, we investigated the effects of this background on the deflection of light, which is influenced by the parameters associated with the wormhole throat and the topological defect.
Journal Article
Last Interglacial Iberian Neandertals as fisher-hunter-gatherers
The origins of marine resource consumption by humans have been much debated. Zilhão et al. present evidence that, in Atlantic Iberia's coastal settings, Middle Paleolithic Neanderthals exploited marine resources at a scale on par with the modern human–associated Middle Stone Age of southern Africa (see the Perspective by Will). Excavations at the Figueira Brava site on Portugal's Atlantic coast reveal shell middens rich in the remains of mollusks, crabs, and fish, as well as terrestrial food items. Familiarity with the sea and its resources may thus have been widespread for residents there in the Middle Paleolithic. The Figueira Brava Neanderthals also exploited stone pine nuts in a way akin to that previously identified in the Holocene of Iberia. These findings add broader dimensions to our understanding of the role of aquatic resources in the subsistence of Paleolithic humans. Science , this issue p. eaaz7943 ; see also p. 1422 The subsistence base of coastal Portugal’s Last Interglacial Neandertals was as broad as that of present-day humans. Marine food–reliant subsistence systems such as those in the African Middle Stone Age (MSA) were not thought to exist in Europe until the much later Mesolithic. Whether this apparent lag reflects taphonomic biases or behavioral distinctions between archaic and modern humans remains much debated. Figueira Brava cave, in the Arrábida range (Portugal), provides an exceptionally well preserved record of Neandertal coastal resource exploitation on a comparable scale to the MSA and dated to ~86 to 106 thousand years ago. The breadth of the subsistence base—pine nuts, marine invertebrates, fish, marine birds and mammals, tortoises, waterfowl, and hoofed game—exceeds that of regional early Holocene sites. Fisher-hunter-gatherer economies are not the preserve of anatomically modern people; by the Last Interglacial, they were in place across the Old World in the appropriate settings.
Journal Article
MC3R links nutritional state to childhood growth and the timing of puberty
The state of somatic energy stores in metazoans is communicated to the brain, which regulates key aspects of behaviour, growth, nutrient partitioning and development
1
. The central melanocortin system acts through melanocortin 4 receptor (MC4R) to control appetite, food intake and energy expenditure
2
. Here we present evidence that MC3R regulates the timing of sexual maturation, the rate of linear growth and the accrual of lean mass, which are all energy-sensitive processes. We found that humans who carry loss-of-function mutations in
MC3R
, including a rare homozygote individual, have a later onset of puberty. Consistent with previous findings in mice, they also had reduced linear growth, lean mass and circulating levels of IGF1. Mice lacking
Mc3r
had delayed sexual maturation and an insensitivity of reproductive cycle length to nutritional perturbation. The expression of
Mc3r
is enriched in hypothalamic neurons that control reproduction and growth, and expression increases during postnatal development in a manner that is consistent with a role in the regulation of sexual maturation. These findings suggest a bifurcating model of nutrient sensing by the central melanocortin pathway with signalling through MC4R controlling the acquisition and retention of calories, whereas signalling through MC3R primarily regulates the disposition of calories into growth, lean mass and the timing of sexual maturation.
MC3R deficiency is associated with a delay in the onset of puberty, and a reduction in growth and lean mass.
Journal Article
Gravitational lensing in a topologically charged Eddington-inspired Born–Infeld spacetime
In the present paper, we study several aspects of gravitational lensing caused by a topologically charged Monopole/Wormhole, both in the weak field limit and in the strong field limit. We calculate the light deflection and then use it to determine the observables, with which one can investigate the existence of these objects through observational tools. We emphasize that the presence of the topological charge produces changes in the observables in relation to the case of General Relativity Ellis–Bronnikov wormhole.
Journal Article
Composite Analysis of the Virome and Bacteriome of HIV/HPV Co-Infected Women Reveals Proxies for Immunodeficiency
The human cervical microbiome is complex, and its role in health and disease has just begun to be elucidated. In this study, 57 cervical swab samples from 19 HIV/HPV co-infected women were analyzed for both virome and bacteriome composition. Virome analysis focused on circular DNA viruses through rolling circle amplification followed by next-generation sequencing (NGS). Data were assigned to virus families and genera, and HPV types were identified. NGS data of bacterial 16S from a subset of 24 samples were assigned to operational taxonomic units and classified according to vaginal microbiome community state types (CSTs). Four viral families were found: Papillomaviridae, Anelloviridae, Genomoviridae, and Herpesviridae. Papillomavirus reads were more abundant in women with premalignant cervical lesions, which were also strongly associated with multiple (≥3) high-risk HPV infection. Anellovirus read abundance was negatively correlated with host CD4+ T-cell counts. The bacteriome revealed the presence of CST III and CST IV, and women with ≥1% frequency of genomovirus or herpesvirus reads displayed an increased risk of carrying CST IV. By characterizing the composition of the cervical circular DNA viruses and the bacteriome of HIV/HPV co-infected women, we identified putative interactions between these two microorganism communities and their associations with patients’ clinical characteristics, notably immunodeficiency status.
Journal Article
Sensitivity of freshwater species under single and multigenerational exposure to seawater intrusion
This study was funded by National Funds (OE) through FCT/MEC and co-funded by FEDER, through COMPETE (POFC), by FSE and POPH (Programme Cieˆncia 2007-8) and the research project SALTFREE (PTDC/AAC-CLI/111706/2009). C.V. is a grant holder from FCT (ref. SFRH/BD/81717/2011).
Journal Article
Analysis of the cervical microbiome and potential biomarkers from postpartum HIV-positive women displaying cervical intraepithelial lesions
The cervical microbiota composition and diversity of HIV-positive women in the postpartum period is unknown. Using a high-throughput bacterial 16S rRNA gene sequencing, we identified four community state types (CSTs). CST III (
Lactobacillusdominant
) and CST IV (IV-A, IV-B.1, IV-B.2; high-diversity) were found in 41% and 59% of samples, respectively. We did not find association of any CST to postpartum period (six or twelve months), HPV infection or cytology (normal or lesion). However, five bacterial genera were associated with cervical lesions (
Gardnerella, Aerococcus, Schlegelella, Moryella
and
Bifidobacterium
), with significant odds ratio (OR) of 40 (2.28–706) for the presence of
Moryella
and 3.5 (1.36–8.9) for
Schlegelella
. Longitudinal analysis of samples at postpartum that regressed (lesion to normal), progressed (normal to lesion) and maintained the cytology (lesion or normal) evidenced
Gardnerella
with a significantly higher abundance in regressing lesions. In the current study, we report the first data on the cervical microbiota of HIV-positive women in the postpartum period. Consistent with previous studies of HIV-negative cohorts, HIV-positive women present a stable cervical microbiota of high-diversity in the postpartum period. Our results highlight that specific microbiota species may serve as sensors for changes in the cervical microenvironment associated with cervical lesions.
Journal Article
Untangling the systematic dilemma behind the roughskin spurdog Cirrhigaleus asper (Merrett, 1973) (Chondrichthyes: Squaliformes), with phylogeny of Squalidae and a key to Cirrhigaleus species
Cirrhigaleus comprises a small genus of rare barbel-bearing dogfish sharks with distributions in limited regions of all oceans. Generic validity and taxonomic status of some species are upon controversies by morphological and molecular evidence that often suggest reallocation of Cirrhigaleus species into the genus Squalus . Particularly, the roughskin spurdog C . asper exhibits intermediary morphological characteristics within Squalidae that requires clarification. In the present study, a phylogenetic approach was undertaken to test the correct generic placement of C . asper using novel and revised morphological characters. We performed maximum parsimony analysis of 51 morphological characters of the internal (e.g., neurocranium, clasper cartilages, pectoral and pelvic girdles) and external anatomy applied to 13 terminal taxa. Cirrhigaleus represents a valid genus and it is supported by eight synapomorphies: high number of monospondylous vertebrae; medial nasal lobe supported by fleshy core and innervated by the buccopharyngeal branch of the facial nerve; neurocranium with greatest width across nasal capsules; one facet and one condyle in the puboischiadic bar for articulating with the basipterygium; two intermediate segments between the basipterygium of the pelvic fin and the axial cartilage of the claspers; five terminal clasper cartilages; and posterior medial process of the puboischiadic bar absent. Cirrhigaleus asper is sister-species to a small clade comprising C . barbifer and C . australis which is supported by one synapomorphy, presence of conspicuous cusplets in the dermal denticles. Cirrhigaleus barbifer , C . asper and C . australis are redescribed herein and the neotype of C . barbifer is designated. A key to Cirrhigaleus species is also given and the inner relationships within Squalus is tentatively discussed.
Journal Article