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1.
Phys Rev Lett ; 131(9): 091801, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37721818

RESUMO

We measured the nuclear-recoil ionization yield in silicon with a cryogenic phonon-sensitive gram-scale detector. Neutrons from a monoenergetic beam scatter off of the silicon nuclei at angles corresponding to energy depositions from 4 keV down to 100 eV, the lowest energy probed so far. The results show no sign of an ionization production threshold above 100 eV. These results call for further investigation of the ionization yield theory and a comprehensive determination of the detector response function at energies below the keV scale.

2.
Phys Rev Lett ; 127(6): 061801, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34420312

RESUMO

We present limits on spin-independent dark matter-nucleon interactions using a 10.6 g Si athermal phonon detector with a baseline energy resolution of σ_{E}=3.86±0.04(stat)_{-0.00}^{+0.19}(syst) eV. This exclusion analysis sets the most stringent dark matter-nucleon scattering cross-section limits achieved by a cryogenic detector for dark matter particle masses from 93 to 140 MeV/c^{2}, with a raw exposure of 9.9 g d acquired at an above-ground facility. This work illustrates the scientific potential of detectors with athermal phonon sensors with eV-scale energy resolution for future dark matter searches.

3.
Phys Rev Lett ; 127(8): 081802, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34477436

RESUMO

The Cryogenic Dark Matter Search low ionization threshold experiment (CDMSlite) achieved efficient detection of very small recoil energies in its germanium target, resulting in sensitivity to lightly ionizing particles (LIPs) in a previously unexplored region of charge, mass, and velocity parameter space. We report first direct-detection limits calculated using the optimum interval method on the vertical intensity of cosmogenically produced LIPs with an electric charge smaller than e/(3×10^{5}), as well as the strongest limits for charge ≤e/160, with a minimum vertical intensity of 1.36×10^{-7} cm^{-2} s^{-1} sr^{-1} at charge e/160. These results apply over a wide range of LIP masses (5 MeV/c^{2} to 100 TeV/c^{2}) and cover a wide range of ßγ values (0.1-10^{6}), thus excluding nonrelativistic LIPs with ßγ as small as 0.1 for the first time.

4.
Psychol Med ; 50(16): 2702-2710, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31637990

RESUMO

BACKGROUND: Social cognition has been associated with functional outcome in patients with first episode psychosis (FEP). Social cognition has also been associated with neurocognition and cognitive reserve. Although cognitive reserve, neurocognitive functioning, social cognition, and functional outcome are related, the direction of their associations is not clear. Therefore, the main aim of this study was to analyze the influence of social cognition as a mediator between cognitive reserve and cognitive domains on functioning in FEP both at baseline and at 2 years. METHODS: The sample of the study was composed of 282 FEP patients followed up for 2 years. To analyze whether social cognition mediates the influence of cognitive reserve and cognitive domains on functioning, a path analysis was performed. The statistical significance of any mediation effects was evaluated by bootstrap analysis. RESULTS: At baseline, as neither cognitive reserve nor the cognitive domains studied were related to functioning, the conditions for mediation were not satisfied. Nevertheless, at 2 years of follow-up, social cognition acted as a mediator between cognitive reserve and functioning. Likewise, social cognition was a mediator between verbal memory and functional outcome. The results of the bootstrap analysis confirmed these significant mediations (95% bootstrapped CI (-10.215 to -0.337) and (-4.731 to -0.605) respectively). CONCLUSIONS: Cognitive reserve and neurocognition are related to functioning, and social cognition mediates in this relationship.


Assuntos
Reserva Cognitiva , Funcionamento Psicossocial , Transtornos Psicóticos/psicologia , Cognição Social , Adolescente , Adulto , Feminino , Humanos , Modelos Lineares , Masculino , Análise de Mediação , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/diagnóstico , Adulto Jovem
5.
Acta Psychiatr Scand ; 141(6): 541-552, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31746462

RESUMO

AIMS: Here, we present a clustering strategy to identify phenotypes of antipsychotic (AP) response by using longitudinal data from patients presenting first-episode psychosis (FEP). METHOD: One hundred and ninety FEP with complete data were selected from the PEPs project. The efficacy was assessed using total PANSS, and adverse effects using total UKU, during one-year follow-up. We used the Klm3D method to cluster longitudinal data. RESULTS: We identified four clusters: cluster A, drug not toxic and beneficial; cluster B, drug beneficial but toxic; cluster C, drug neither toxic nor beneficial; and cluster D, drug toxic and not beneficial. These groups significantly differ in baseline demographics, clinical, and neuropsychological characteristics (PAS, total PANSS, DUP, insight, pIQ, age of onset, cocaine use and family history of mental illness). CONCLUSIONS: The results presented here allow the identification of phenotypes of AP response that differ in well-known simple and classic clinical variables opening the door to clinical prediction and application of personalized medicine.


Assuntos
Antipsicóticos/uso terapêutico , Fenótipo , Medicina de Precisão , Transtornos Psicóticos/tratamento farmacológico , Transtornos Psicóticos/psicologia , Estudos de Coortes , Feminino , Humanos , Masculino
6.
Rev Chil Pediatr ; 91(6): 874-880, 2020 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-33861823

RESUMO

INTRODUCTION: The hypernatremic neonatal dehydration is a severe condition whose incidence has increased in recent years resulting in complications leading to the hospitalization of the newborn. OBJECTIVE: Describe the clinical and laboratory characteristics of term-newborns with Hypernatremic Dehy dration diagnosis. PATIENTS AND METHOD: Descriptive observational study of hospitalized term- newborns due to hypernatremic dehydration between a period from 2014 to 2016. Term newborns over 37 weeks with clinical signs of dehydration (dry mucous membranes, depressed fontanel, tear less crying, signs of the cutaneous pleat), and/or excessive weight loss greater than 7% and serum sodium greater than 145 mEq/L were included. Sociodemographic and biochemical variables were recorded for analysis. RESULTS: 43 neonates were included. 60.5 percent of their mothers were pri- miparous, 90 percent of neonates received exclusive breastfeeding, mothers reported breastfeeding problems in 76.7 percent. Incoming neonates reported weight loss compared to birth weight at 15.3% on average. 83.3% had public health insurance. 65.1% had dehydration clinical signs at entry and 83.5% transient neurological signs. The average sodium was 155 mEq/L at revenue. The sodium decrease in the first 24 hours of handling was 7.74 mEq/L (0.32mEq/L per hour). The correction of the hypernatremia was 55.8% by oral intake and 4 days hospital stay on average. CONCLUSIONS: The feeding's problems came up in a (76%), primiparous mothers in an (88.4%). 90.6 percent of this population administered exclusive breastfeeding, results that can help to alert the health professional to timely identification, warning signs, and early post-discharge control and preventive measures.


Assuntos
Desidratação/diagnóstico , Hospitalização , Hipernatremia/diagnóstico , Adolescente , Adulto , Peso ao Nascer , Aleitamento Materno/estatística & dados numéricos , Desidratação/epidemiologia , Desidratação/terapia , Feminino , Humanos , Hipernatremia/epidemiologia , Hipernatremia/terapia , Recém-Nascido , Tempo de Internação , Masculino , Mães , Estudos Retrospectivos , Redução de Peso , Adulto Jovem
8.
Lupus ; 28(4): 565-568, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30862250

RESUMO

Organizing pneumonia is an inflammatory lung entity that presents with a huge variety of clinical, radiological and pathological patterns. Organizing pneumonia can be idiopathic or secondary to other diseases. Corticosteroid therapy is usually the first-line treatment showing clinical improvement in most cases. This report presents the case of a 56-year-old woman with systemic lupus erythematosus who was diagnosed with an organizing pneumonia and showed a poor response to steroid and azathioprine treatment. We considered the use of belimumab, which resulted in excellent clinical and radiological outcomes.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Bronquiolite Obliterante/tratamento farmacológico , Bronquiolite Obliterante/etiologia , Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/complicações , Anticorpos Antinucleares/sangue , Anticorpos Monoclonais Humanizados/administração & dosagem , Azatioprina/administração & dosagem , Azatioprina/efeitos adversos , Azatioprina/uso terapêutico , Bronquiolite Obliterante/sangue , Progressão da Doença , Tolerância a Medicamentos , Feminino , Seguimentos , Humanos , Imunossupressores/administração & dosagem , Leucocitose/sangue , Pulmão/diagnóstico por imagem , Pulmão/patologia , Lúpus Eritematoso Sistêmico/sangue , Pessoa de Meia-Idade , Prednisolona/administração & dosagem , Prednisolona/uso terapêutico , Testes de Função Respiratória , Tomógrafos Computadorizados , Resultado do Tratamento
9.
Eur Child Adolesc Psychiatry ; 28(10): 1395-1405, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30843122

RESUMO

A precise description of the inflammatory response in first-episode psychosis (FEP) by age of onset does not exist. We explored baseline and 6-month follow-up differences in the pro/anti-inflammatory balance in plasma and peripheral blood mononuclear cells in adolescent-onset FEP (≤ 18 y.o., N = 27) and adult-onset FEP (≥ 25 y.o., N = 43) using non-parametric 1-category ANCOVA, with age group as an independent variable and values of pro- and anti-inflammatory markers at baseline and at follow-up as dependent variables. We used a non-parametric repeated-measures mixed-effects model to explore the baseline/6-month change in pro- and anti-inflammatory markers within adolescent- and adult-onset groups, exploring differential trajectories of change by means of the interaction of time by age-of-onset group. Levels of the nuclear transcription factor (NFκB), a master regulator of the inflammatory and oxido/nitrosative status of cells, were higher in adolescent-onset FEP both at baseline and after 6 months. During follow-up, we found further increases in levels of soluble inflammatory markers (PGE2 and NO2-) only in adolescent-onset FEP. In contrast, in adult-onset FEP, the expression of inducible NO synthase (iNOS), which is also pro-inflammatory, tended to decrease, with no further increase in other pro-inflammatory markers. Significant differences in the direction of change by age-of-onset cohort exist only for NFκB (F = 4.165, df = 2, 70.95, p = 0.019). Our results support the existence of changes in the pro/anti-inflammatory balance in FEP depending on the neurodevelopmental stage at illness onset. These results also suggest that inflammation may be a potential therapeutic target in adolescent-onset FEP.


Assuntos
Biomarcadores/sangue , Inflamação/metabolismo , Transtornos Psicóticos/etiologia , Adolescente , Adulto , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Adulto Jovem
10.
Phys Rev Lett ; 120(6): 061802, 2018 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-29481237

RESUMO

We report the result of a blinded search for weakly interacting massive particles (WIMPs) using the majority of the SuperCDMS Soudan data set. With an exposure of 1690 kg d, a single candidate event is observed, consistent with expected backgrounds. This analysis (combined with previous Ge results) sets an upper limit on the spin-independent WIMP-nucleon cross section of 1.4×10^{-44} (1.0×10^{-44}) cm^{2} at 46 GeV/c^{2}. These results set the strongest limits for WIMP-germanium-nucleus interactions for masses >12 GeV/c^{2}.

11.
Phys Rev Lett ; 121(5): 051301, 2018 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-30118251

RESUMO

We present the first limits on inelastic electron-scattering dark matter and dark photon absorption using a prototype SuperCDMS detector having a charge resolution of 0.1 electron-hole pairs (CDMS HVeV, a 0.93 g CDMS high-voltage device). These electron-recoil limits significantly improve experimental constraints on dark matter particles with masses as low as 1 MeV/c^{2}. We demonstrate a sensitivity to dark photons competitive with other leading approaches but using substantially less exposure (0.49 g d). These results demonstrate the scientific potential of phonon-mediated semiconductor detectors that are sensitive to single electronic excitations.

12.
Acta Psychiatr Scand ; 138(5): 441-455, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30105820

RESUMO

OBJECTIVE: Cognitive reserve (CR) refers to the brain's capacity to cope with pathology in order to minimize the symptoms. CR is associated with different outcomes in severe mental illness. This study aimed to analyze the impact of CR according to the diagnosis of first-episode affective or non-affective psychosis (FEP). METHOD: A total of 247 FEP patients (211 non-affective and 36 affective) and 205 healthy controls were enrolled. To assess CR, common proxies have been integrated (premorbid IQ; education-occupation; leisure activities). The groups were divided into high and low CR. RESULTS: In non-affective patients, those with high CR were older, had higher socioeconomic status (SES), shorter duration of untreated psychosis, and a later age of onset. They also showed greater performance in most cognitive domains. In affective patients, those with a greater CR showed a higher SES, better functioning, and greater verbal memory performance. CONCLUSION: CR plays a differential role in the outcome of psychoses according to the diagnosis. Specifically, in order to address the needs of non-affective patients with low CR, cognitive rehabilitation treatments will need to be 'enriched' by adding pro-cognitive pharmacological agents or using more sophisticated approaches. However, a functional remediation therapy may be of choice for those with an affective psychosis and low CR.


Assuntos
Transtornos Psicóticos Afetivos/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Reserva Cognitiva/fisiologia , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/fisiopatologia , Adulto , Transtornos Psicóticos Afetivos/complicações , Fatores Etários , Idade de Início , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/terapia , Remediação Cognitiva , Feminino , Seguimentos , Humanos , Masculino , Transtornos Psicóticos/complicações , Esquizofrenia/complicações , Classe Social , Adulto Jovem
13.
Eur Arch Psychiatry Clin Neurosci ; 268(7): 699-711, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29164332

RESUMO

Individual changes over time in cognition in patients with psychotic disorders have been studied very little, especially in the case of first episode psychosis (FEP). We aimed to establish whether change in individual trajectories in cognition over 2 years of a sample of 159 FEP patients was reliable and clinically significant, using the reliable change index (RCI) and clinically significant change (CSC) methods. We also studied a sample of 151 matched healthy controls. Patients and controls were assessed with a set of neuropsychological tests, as well as premorbid, clinical and functionality measures. We analysed the course of cognitive measures over time, using analysis of variance, and the individual trajectories in the cognitive measures with the regression-based RCI (RCISRB) and the CSC. The RCISRB showed that between 5.4 and 31.2% of the patients showed deterioration patterns, and between 0.6 and 8.8% showed improvement patterns in these tests over time. Patients showing better cognitive profiles according to RCISRB (worsening in zero to two cognitive measures) showed better premorbid, clinical and functional profiles than patients showing deterioration patterns in more than three tests. When combining RCISRB and CSC values, we found that less than 10% of patients showed improvement or deterioration patterns in executive function and attention measures. These results support the view that cognitive impairments are stable over the first 2 years of illness, but also that the analysis of individual trajectories could help to identify a subgroup of patients with particular phenotypes, who may require specific interventions.


Assuntos
Atenção/fisiologia , Disfunção Cognitiva/fisiopatologia , Progressão da Doença , Função Executiva/fisiologia , Transtornos Psicóticos/fisiopatologia , Adolescente , Adulto , Disfunção Cognitiva/etiologia , Feminino , Seguimentos , Humanos , Masculino , Testes Neuropsicológicos , Transtornos Psicóticos/complicações , Adulto Jovem
14.
Pharmacogenomics J ; 16(5): 439-45, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27272046

RESUMO

This study investigated whether the risk of presenting antipsychotic (AP)-induced extrapyramidal symptoms (EPS) could be related to single-nucleotide polymorphisms (SNPs) in a naturalistic cohort of first episode psychosis (FEP) patients. Two hundred and two SNPs in 31 candidate genes (involved in dopamine, serotonin and glutamate pathways) were analyzed in the present study. One hundred and thirteen FEP patients (43 presenting EPS and 70 non-presenting EPS) treated with high-potency AP (amisulpride, paliperidone, risperidone and ziprasidone) were included in the analysis. The statistical analysis was adjusted by age, gender, AP dosage, AP combinations and concomitant treatments as covariates. Four SNPs in different genes (DRD2, SLC18A2, HTR2A and GRIK3) contributed significantly to the risk of EPS after correction for multiple testing (P<1 × 10(-4)). These findings support the involvement of dopamine, serotonin and glutamate pathways in AP-induced EPS.


Assuntos
Antipsicóticos/efeitos adversos , Doenças dos Gânglios da Base/induzido quimicamente , Dopamina/metabolismo , Ácido Glutâmico/metabolismo , Variantes Farmacogenômicos , Polimorfismo de Nucleotídeo Único , Transtornos Psicóticos/tratamento farmacológico , Serotonina/metabolismo , Adolescente , Adulto , Doenças dos Gânglios da Base/genética , Doenças dos Gânglios da Base/metabolismo , Doenças dos Gânglios da Base/fisiopatologia , Estudos de Casos e Controles , Criança , Feminino , Seguimentos , Estudos de Associação Genética , Predisposição Genética para Doença , Haplótipos , Humanos , Estudos Longitudinais , Masculino , Farmacogenética , Fenótipo , Estudos Prospectivos , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/fisiopatologia , Receptor 5-HT2A de Serotonina/genética , Receptores de Dopamina D2/genética , Receptores de Ácido Caínico/genética , Medição de Risco , Fatores de Risco , Espanha , Resultado do Tratamento , Proteínas Vesiculares de Transporte de Monoamina/genética , Adulto Jovem , Receptor de GluK3 Cainato
15.
Phys Rev Lett ; 116(7): 071301, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26943526

RESUMO

The CDMS low ionization threshold experiment (CDMSlite) uses cryogenic germanium detectors operated at a relatively high bias voltage to amplify the phonon signal in the search for weakly interacting massive particles (WIMPs). Results are presented from the second CDMSlite run with an exposure of 70 kg day, which reached an energy threshold for electron recoils as low as 56 eV. A fiducialization cut reduces backgrounds below those previously reported by CDMSlite. New parameter space for the WIMP-nucleon spin-independent cross section is excluded for WIMP masses between 1.6 and 5.5 GeV/c^{2}.

16.
Psychol Med ; 46(10): 2133-44, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27055381

RESUMO

BACKGROUND: Cognitive deficits are present from the onset of psychosis and are considered a core feature of the disorder. Increasing evidence suggests that cognitive function is associated with inflammatory processes. This study evaluated the association between cognition and inflammatory biomarkers in first-episode psychosis (FEP), in order to identify cognitive phenotypes from inflammatory expression profiles. METHOD: A case-control study of 92 FEP patients and 80 matched controls was used. Neurocognitive assessment, including verbal ability, sustained attention, verbal memory, working memory and executive function, was performed. The expression of pro- and anti-inflammatory mediators of the main intracellular inflammatory pathway was measured in peripheral blood mononuclear cells and plasma. RESULTS: FEP patients performed worse in all cognitive domains compared to controls and had higher expression of pro-inflammatory mediators and lower expression of anti-inflammatory mediators. In the FEP group, cognition and psychopathology were associated with inflammation. Hierarchical regression analysis showed that association between the anti-inflammatory prostaglandin 15d-PGJ2 and sustained attention on one hand, and COX-2 expression and executive function on the other, were statistically significant. CONCLUSIONS: Our study provides evidence for an association between anti-inflammatory biomarkers and cognition in FEP. The identification of a subgroup of patients based on these measures could be useful to guide treatment programmes by providing tools to select a personalized treatment approach, but longitudinal studies are needed before. In the future, establishment of biomarkers linked to cognition would be useful to monitor the course of cognitive impairment, but substantially more data will be required. Determination of IκBα, the inhibitory protein of the pro-inflammatory transcription factor NFκB, could be useful in early phases to assess clinical severity.


Assuntos
Disfunção Cognitiva , Ciclo-Oxigenase 2/metabolismo , Função Executiva/fisiologia , Inflamação , Prostaglandina D2/análogos & derivados , Transtornos Psicóticos , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Disfunção Cognitiva/imunologia , Disfunção Cognitiva/fisiopatologia , Feminino , Humanos , Inflamação/imunologia , Inflamação/fisiopatologia , Masculino , Prostaglandina D2/metabolismo , Transtornos Psicóticos/imunologia , Transtornos Psicóticos/fisiopatologia , Adulto Jovem
17.
Rev Biol Trop ; 64(1): 235-46, 2016 03.
Artigo em Espanhol | MEDLINE | ID: mdl-28862759

RESUMO

Wild specimens of Vanilla planifolia represent a vital part of this resource primary gene pool, and some plants have only been reported in Oaxaca, Mexico. For this reason, we studied its geographical distribution within the state, to locate and describe the ecological characteristics of the areas where they have been found, in order to identify potential areas of establishment. The method comprised four stages: 1) the creation of a database with herbarium records, 2) the construction of the potential distribution based on historical herbarium records for the species, using the model of maximum entropy (MaxEnt) and 22 bioclimatic variables as predictors; 3) an in situ systematic search of individuals, based on herbarium records and areas of potential distribution in 24 municipalities, to determine the habitat current situation and distribution; 4) the description of the environmental factors of potential ecological niches generated by MaxEnt. A review of herbarium collections revealed a total of 18 records of V. planifolia between 1939 and 1998. The systematic search located 28 plants distributed in 12 sites in 95 364 Km(2). The most important variables that determined the model of vanilla potential distribution were: precipitation in the rainy season (61.9 %), soil moisture regime (23.4 %) and precipitation during the four months of highest rainfall (8.1 %). The species potential habitat was found to be distributed in four zones: wet tropics of the Gulf of Mexico, humid temperate, humid tropical, and humid temperate in the Pacific. Precipitation oscillated within the annual ranges of 2 500 to 4 000 mm, with summer rains, and winter precipitation as 5 to 10 % of the total. The moisture regime and predominating climate were udic type I (330 to 365 days of moisture) and hot humid (Am/A(C) m). The plants were located at altitudes of 200 to 1 190 masl, on rough hillsides that generally make up the foothills of mountain systems, with altitudes of 1 300 to 2 500 masl. In natural conditions, distribution of the species is not limited to high evergreen forests, since it was also found in mountain mesophyll and tropical evergreen forests. The location of new specimens of V. planifolia in its wild condition reduces the potential distribution area by 66 %. This area is fragmented into three geographically separated areas. Habitat reduction was due to the increased number of located plants that define the environmental conditions into a more accurate level. Conservation actions can thus be designed and implemented, focusing on more specific areas within the state of Oaxaca, Mexico.


Assuntos
Vanilla/classificação , Biodiversidade , Geografia , México , Estações do Ano
18.
Phys Rev Lett ; 114(11): 111302, 2015 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-25839256

RESUMO

While the standard model of particle physics does not include free particles with fractional charge, experimental searches have not ruled out their existence. We report results from the Cryogenic Dark Matter Search (CDMS II) experiment that give the first direct-detection limits for cosmogenically produced relativistic particles with electric charge lower than e/6. A search for tracks in the six stacked detectors of each of two of the CDMS II towers finds no candidates, thereby excluding new parameter space for particles with electric charges between e/6 and e/200.

19.
Anim Genet ; 46(4): 452-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26153924

RESUMO

In the course of human migrations, domestic animals often have been translocated to islands with the aim of assuring food availability. These founder events are expected to leave a genetic footprint that may be recognised nowadays. Herewith, we have examined the mitochondrial diversity of goat populations living in the Canarian and Balearic archipelagos. Median-joining network analysis produced very distinct network topologies for these two populations. Indeed, a majority of Canarian goats shared a single ancestral haplotype that segregated in all sampled islands, suggesting a single founder effect followed by a stepping-stone pattern of diffusion. This haplotype also was present in samples collected from archaeological assemblies at Gran Canaria and Lanzarote, making evident its widespread distribution in ancient times. In stark contrast, goats from Majorca and Ibiza did not share any mitochondrial haplotypes, indicating the occurrence of two independent founder events. Furthermore, in Majorcan goats, we detected the segregation of the mitochondrial G haplogroup that has only been identified in goats from Egypt, Iran and Turkey. This finding suggests the translocation of Asian and/or African goats to Majorca, possibly as a consequence of the Phoenician and Carthaginian colonisations of this island.


Assuntos
DNA Mitocondrial/genética , Efeito Fundador , Genética Populacional , Cabras/genética , Animais , Animais Domésticos/genética , Pool Gênico , Deriva Genética , Haplótipos , Ilhas , Dados de Sequência Molecular , Análise de Sequência de DNA , Espanha
20.
Phys Rev Lett ; 112(4): 041302, 2014 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-24580434

RESUMO

SuperCDMS is an experiment designed to directly detect weakly interacting massive particles (WIMPs), a favored candidate for dark matter ubiquitous in the Universe. In this Letter, we present WIMP-search results using a calorimetric technique we call CDMSlite, which relies on voltage-assisted Luke-Neganov amplification of the ionization energy deposited by particle interactions. The data were collected with a single 0.6 kg germanium detector running for ten live days at the Soudan Underground Laboratory. A low energy threshold of 170 eVee (electron equivalent) was obtained, which allows us to constrain new WIMP-nucleon spin-independent parameter space for WIMP masses below 6 GeV/c2.

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