SHARDS: Constraints on the dust attenuation law of star-forming galaxies at z~2

We make use of SHARDS, an ultra-deep (<26.5AB) galaxy survey that provides optical photo-spectra at resolution R~50, via medium band filters (FWHM~150A). This dataset is combined with ancillary optical and NIR fluxes to constrain the dust attenuation law in the rest-frame NUV region of star-forming galaxies within the redshift window 1.5<z<3. We focus on the NUV bump strength (B) and the total-to-selective extinction ratio (Rv), targeting a sample of 1,753 galaxies. By comparing the data with a set of population synthesis models coupled to a parametric dust attenuation law, we constrain Rv and B, as well as the colour excess, E(B-V). We find a correlation between Rv and B, that can be interpreted either as a result of the grain size distribution, or a variation of the dust geometry among galaxies. According to the former, small dust grains are associated with a stronger NUV bump. The latter would lead to a range of clumpiness in the distribution of dust within the interstellar medium of star-forming galaxies. The observed wide range of NUV bump strengths can lead to a systematic in the interpretation of the UV slope ($\beta$) typically used to characterize the dust content. In this study we quantify these variations, concluding that the effects are $\Delta\beta$~0.4.Comment: 13 pages, 11+2 figures, 3 tables. MNRAS, in pres

Seroprevalencija Dirofilaria immitis u pasa iz skloništa za životinje u kolumbijskoj regiji kave (Eje Cafetero)

In Colombia, there are reports of approximately 6.4 million pets, making this the fourth country in Latin America and leading the pet sector with an annual growth of 13%. This study aimed to determine the seroprevalence of Dirofilaria immitis, a parasitic nematode, in 170 canines from the municipalities of Pereira, Santa Rosa de Cabal, and La Virginia, located in the department of Risaralda and the municipalities of Calarca and Armenia in the department of Quindio. A cross-sectional study was carried out on canines from animal shelters during the period 2021–2022. Blood samples were taken, and in vitro immunochromatography was performed to detect specific lesions for Dirofilaria immitis. A peripheral blood smear confirmed positive patients, and a chest x-ray was performed to show changes in the morphology of the heart and blood vessels. Seroprevalence was determined by calculating proportions with the 95% confidence interval determined by the exact or Clopper-Pearson method for a proportion based on sample size and the number of positive cases. The seroprevalence of the test for Dirofilaria immitis was 0.62% (95% CI = 0.016–3.42%). This parasite is a nematode of low distribution in areas of the coffee region. However, surveillance programmes that help control and reduce its transmission should be established.Postoje izvješća o gotovo 6.400.000 kućnih ljubimaca u Kolumbiji i to je četvrta zemlja u Latinskoj Americi u sektoru kućnih ljubimaca, s godišnjim rastom od 13 %. Cilj je ove studije jest utvrditi seroprevalenciju Dirofilaria immitis u 170 pasa iz općina Pereira, Santa Rosa de Cabal i La Virginia, koje se nalaze u departmanu Risaralda i u općinama Calarca i Armenia u departmanu Quindio. Provedena je presječna studija na psima iz skloništa za životinje tijekom godine 2021.-2022. Uzeti su uzorci krvi i obavljena je in vitro imunokromatografija za detekciju lezija specifičnih za Dirofilaria immitis. Razmaz periferne kriv potvrdio je pozitivne pacijente i obavljen je RTG prsnog koša da bi se vidjele promjene u morfologiji srca i krvnih žila. Seroprevalencija je utvrđena izračunom omjera uz interval pouzdanosti od 95% određen preciznom ili Clopper-Pearson metodom za omjer na temelju veličine uzorka i broja pozitivnih slučajeva. Seroprevalencija testa na Dirofilaria immitis bila je 0,62 % (95% CI = 0,016-3,42 %). Ovaj je parazit oblić u područjima regije kave niske rasprostranjenosti, ali predlaže se uspostaviti programe nadzora koji će pomoći kontrolirati i reducirati njegov prijenos

Detection of reactive canines to Leptospira in Campeche City, Mexico

ABSTRACT Leptospira reactivity in stray and household dogs in Campeche as well as associated risk factors to the seropositivity in household dogs have been herein determined. the survey included 323 dogs, 142 of which were stray dogs and 181 household dogs. nine Leptospira interrogans serovars were tested by the microagglutination test. reactivity was 21.3 % (69/323), 17.2 % corresponded to household dogs and 26.7 % to stray dogs. Leptospira Canicola (29 %), Leptospira hardjo (22.58 %), and Leptospira icterohaemorrhagiae (16.12 %) were the most common serovars reacting against the serum of household animals, while Leptospira Canicola (15.78 %), Leptospira icterohaemorrhagiae (13.15 %), and Leptospira Pomona (7.89 %) were those reacting in stray dogs. results showed that all dogs have been in contact with different Leptospira serovars and outdoor exposure is the main infection risk factor. Key words: seroreactivity, Leptospira, dogs, urban area RESUMEN Detección de caninos reaccionantes a Leptospira en la ciudad de Campeche, México. Se determinó la reactividad frente a distintos serovares de Leptospira de 142 perros callejeros y 181 perros domésticos de la ciudad de Campeche, así como los factores de riesgo asociados a la serorreactividad de los perros domésticos. Se utilizaron 9 serovares de Leptospira interrogans en la prueba de microaglutinación. la reactividad global a Leptospira fue del 21,3 % (69/323), alcanzó el 17,2 % en perros domiciliados y el 26,7 % en perros callejeros. las serovariedades que reaccionaron a los sueros de caninos domésticos fueron Leptospira Canicola (29 %), Leptospira hardjo (22,58 %) y Leptospira icterohaemorrhagiae (16,12 %); las que reaccionaron a los sueros de perros callejeros fueron Leptospira Canicola (15,78 %), Leptospira icterohaemorrhagiae (13,15 %) y Leptospira Pomona (7,89 %). los resultados indican que todos los perros evaluados han estado en contacto con diferentes serovares de Leptospira y que la calle es el principal factor de riesgo para la infección. Palabras clave: serorreactividad, Leptospira, perros, área urbana leptospirosis is a worldwide zoonosis that is frequently found in tropical areas where spread conditions are favorable; as a result it is considered a public health concern. leptospirosis is caused by Leptospira interrogans affecting man and some wild and domestic animals, which include cows, pigs, horses, sheep, dogs, cats as well as rodents such as mice and rats; the latter being considered the main Leptospira reservoirs transmission occurs by direct contact with contaminated urine or indirectly through soil and water which has been contaminated by the urine of the above mentioned animals. even though rodents are considered the main reservoir, dogs could have epidemiological relevance due to their close association with man in non occupational environments. recent studies carried out in countries like Colombia have shown a prevalence of 20 % in household dogs (8) and in aragua, Venezuela, a INFORME BREVE iSSn 0325-7541 revista argentina de microbiología (2013) 45: 34-38 35 prevalence of 100 % in stray dogs (4). on the other hand, in mexico, a prevalence of 23 % was reported in household dogs in Jalisco (9), of 38.51 % in stray dogs in the north of mexico City (6), whereas in the Southeast of mexico, that is, Chiapas, a seropositivity of 23 % in household dogs, 55 % in stray dogs (15) and 30.5 % in reservoirs of livestock in the State of Yucatan (1). the objective of this study was to determine Leptospira reactivity in stray and household dogs in the City of Campeche, as well as the serovars and risk factors associated with seroreactivity in household dogs. the State of Campeche is located at 20°51&apos;n, 17°49&apos;S, 89°9&apos;e and 92°28&apos;W on the Yucatan Peninsula, mexico. Campeche, its capital city, lies along the coast line. it has annual temperature and precipitation averages of 28 ºC and 300 mm, respectively. the studied population included stray dogs captured by the Vector-Borne and zoonotic disease department staff of the health ministry and evaluated by a veterinarian. the sample size was based on a proportion of 30 % close to the average prevalence in the States of Chiapas and Yucatan. these states are located in the tropical regions of southeast mexico, as Campeche is, favoring the growth and development of Leptospira. on the other hand, based on their epidemiological experience, experts from the department of health suggested the usage of 30 % prevalence to make an efficient use of resources for this study since there exists no difference between sampling at 30 % or 50 %. Based on information from the department of Vector-Borne and zoonotic diseases, the total canine population in the city is estimated at 57,000 canines. (ing. Carlos Chi tun, personal communication). the required sample size (n = 323) was determined by the proportion method, through the formula n = z 2 . p.q /d 2 , where z 2 = 1.96 for 95 % confidence, p = 30 % prevalence, q = 1-p = 0.7 is the expected variability of the phenomenon to be studied, and d = 5 % is the precision grade. Blood samples were taken from those household dogs whose owners had granted veterinarian permission, and had answered the relevant questionnaire. Canines vaccinated against Leptospira were excluded. a sample of 5 ml of venous blood was taken from all dogs. the samples were analyzed by the Biomed research Center at the university of Campeche. the blood samples were centrifuged at 800 x g for 10 minutes to obtain serum, which was stored at -20 °C until processing. a total of 9 Leptospira interrogans serovars: icterohaemorrhagiae and L. grippotyphosa, were used as antigens for the microscopic agglutination test as these are the serovars most commonly studied in canines in mexico. the cultures were donated by the Veterinary School at unam. Serum was positive when agglutination equal to or greater than 50 % of Leptospira was observed in a 1:100 diluted serum, using an antigen control for each serovar descriptive statistics were used to analyze data using frequency distributions. X 2 (chi square test) was used to determine the association between seropositivity and each of the qualitative variables compiled in the survey at a significant level of p &lt; 0.05 and confidence intervals. a total of 323 canine serums were studied, 181 of which (56 %) were from household dogs and 142 (44 %) were from stray dogs. the overall seroprevalence of leptospirosis was 21.3 % (69/323) positive at titres of 100, 200 and 400 for one or more serovars, 17.2 % (31/181) of which were household dogs and 26.7 % (38/142) were stray dogs. the highest titre was 400 which corresponded to an L. Canicola serovar, found in a stray dog serum. the most commonly detected antibodies in household dogs were against L. Canicola 29 % (9/31), followed by L. hardjo 22.58 % (7/31), L. icterohaemorrhagiae 16.12 % (5/31), L. Pomona 9.67 % (3/31), L. Bataviae 9.67 % (3/31) and L. grippothyphosa 3.22 % (1/31). Coagglutinations were observed in 9.67 % of positive serums, 66.66 % of which showed a titre of 100 and 33.33 % showed a titre of 200. regarding the stray dogs, the most frequent antibodies found were against L. Canicola 15.78 % (6/38), followed by L. icterohaemorrhagiae 13.15 % (5/38), L. Pomona 7.89 % (3/38), L. Bataviae 5.26 % (2/38), L. grippothyphosa 1.38 % (1/38) and L. hardjo 2.63 % (1/38). Coagglutination was shown in 52.63 % of positive serums. the most frequent titre was 100 with 87 %, followed by 10.52 % at 200 and 2.63 % at 400. Serum agglutination was not observed against L. tarassovi, L. Pyrogenes, and L. Sejroe serovars. after evaluating the survey data obtained, where 7 variables were included as risk factors, it was found, according to the bi-factorial analysis, that the factors significantly associated (p &lt; 0.05) with seropositivity were exposure of household dogs to the street, the location of ditches near the homes as well as coexistence with other dogs (the complete list of risk factors analyzed is shown in table 1). the study confirmed the presence of Leptospira reactivity in the canine population and determined a seroreactivity of 21.3 % (69/323) against diverse serovars. this reactivity was higher in stray dogs (26.7 %) than in household dogs (17.2 %). Similar studies in aragua, Venezuela found 100 % (30/30) seroprevalence, Canines reacting to Leptospira in Campeche City. 36 revista argentina de microbiología (2013) 45: 34-38 being L. Canicola, L. icterohaemorrhagiae and L. hardjo the most frequent serovars (4). in Cali, Colombia, 41.1 % seroprevalence was found and the most frequent serovars were L. icterohaemorrhagiae, L. hardjo, L. Gryppotyphosa and L. Canicola (7). in maringa, Brazil a prevalence of 12.2 % was found in 335 canines, being L. Pyrogenes, L. Canicola, L. hardjo, L. Pomona and L. grippotyphosa the serovars found (3). in itapema, Brazil a seroprevalence of 10.5 % was found in 590 canines and L. Pyrogenes, L. Canicola and L. icterohaemorrhagiae serovars were detected (2). in mexico City, the seroprevalence was 38.51 % (52/135) and the serovars detected were L. Canicola, L. icterohaemorrhagiae, L. hardjo and L. Pomona (6). the seroreactivity in stray dogs in this study differed from that in the study mentioned before; however, there is a concordance with the serovars in those studies with the exception of L. Pyrogenes. it was observed that seroreactivity varies from one region to another, where the climate can be an important factor that affects Leptospira prevalence (2). in manizales, Colombia, dogs observed by veterinaries, showed a seropositivity of 20.5 % (41/200), where the main serovars represented were L. icterohaemorrhagiae, L. grippotyphosa, L. Canicola and L. Pomona (10); in Valdivia, Chile there was a prevalence of 14.8 % (59/400) and the mos

Autoantibody screening in Guillain-Barré syndrome

Background: Guillain-Barré syndrome (GBS) is an acute inflammatory neuropathy with a heterogeneous presentation. Although some evidences support the role of autoantibodies in its pathogenesis, the target antigens remain unknown in a substantial proportion of GBS patients. The objective of this study is to screen for autoantibodies targeting peripheral nerve components in Guillain-Barré syndrome. Methods: Autoantibody screening was performed in serum samples from all GBS patients included in the International GBS Outcome study by 11 different Spanish centres. The screening included testing for anti-ganglioside antibodies, anti-nodo/paranodal antibodies, immunocytochemistry on neuroblastoma-derived human motor neurons and murine dorsal root ganglia (DRG) neurons, and immunohistochemistry on monkey peripheral nerve sections. We analysed the staining patterns of patients and controls. The prognostic value of anti-ganglioside antibodies was also analysed. Results: None of the GBS patients (n = 100) reacted against the nodo/paranodal proteins tested, and 61 (61%) were positive for, at least, one anti-ganglioside antibody. GBS sera reacted strongly against DRG neurons more frequently than controls both with IgG (6% vs 0%; p = 0.03) and IgM (11% vs 2.2%; p = 0.02) immunodetection. No differences were observed in the proportion of patients reacting against neuroblastoma-derived human motor neurons. Reactivity against monkey nerve tissue was frequently detected both in patients and controls, but specific patterns were only detected in GBS patients: IgG from 13 (13%) patients reacted strongly against Schwann cells. Finally, we confirmed that IgG anti-GM1 antibodies are associated with poorer outcomes independently of other known prognostic factors. Conclusion: Our study confirms that (1) GBS patients display a heterogeneous repertoire of autoantibodies targeting nerve cells and structures; (2) gangliosides are the most frequent antigens in GBS patients and have a prognostic value; (3) further antigen-discovery experiments may elucidate other potential antigens in GBS

Autoantibody screening in Guillain-Barré syndrome

Background: Guillain?Barré syndrome (GBS) is an acute inflammatory neuropathy with a heterogeneous presentation. Although some evidences support the role of autoantibodies in its pathogenesis, the target antigens remain unknown in a substantial proportion of GBS patients. The objective of this study is to screen for autoantibodies targeting peripheral nerve components in Guillain-Barré syndrome. Methods: Autoantibody screening was performed in serum samples from all GBS patients included in the International GBS Outcome study by 11 different Spanish centres. The screening included testing for anti-ganglioside antibodies, anti-nodo/paranodal antibodies, immunocytochemistry on neuroblastoma-derived human motor neurons and murine dorsal root ganglia (DRG) neurons, and immunohistochemistry on monkey peripheral nerve sections. We analysed the staining patterns of patients and controls. The prognostic value of anti-ganglioside antibodies was also analysed. Results: None of the GBS patients (n = 100) reacted against the nodo/paranodal proteins tested, and 61 (61%) were positive for, at least, one anti-ganglioside antibody. GBS sera reacted strongly against DRG neurons more frequently than controls both with IgG (6% vs 0%; p = 0.03) and IgM (11% vs 2.2%; p = 0.02) immunodetection. No differences were observed in the proportion of patients reacting against neuroblastoma-derived human motor neurons. Reactivity against monkey nerve tissue was frequently detected both in patients and controls, but specific patterns were only detected in GBS patients: IgG from 13 (13%) patients reacted strongly against Schwann cells. Finally, we confirmed that IgG anti-GM1 antibodies are associated with poorer outcomes independently of other known prognostic factor

Accelerated inbreeding depression suggests synergistic epistasis for deleterious mutations in Drosophila melanogaster

Epistasis may have important consequences for a number of issues in quantitative genetics and evolutionary biology. In particular, synergistic epistasis for deleterious alleles is relevant to the mutation load paradox and the evolution of sex and recombination. Some studies have shown evidence of synergistic epistasis for spontaneous or induced deleterious mutations appearing in mutation-accumulation experiments. However, many newly arising mutations may not actually be segregating in natural populations because of the erasing action of natural selection. A demonstration of synergistic epistasis for naturally segregating alleles can be achieved by means of inbreeding depression studies, as deleterious recessive allelic effects are exposed in inbred lines. Nevertheless, evidence of epistasis from these studies is scarce and controversial. In this paper, we report the results of two independent inbreeding experiments carried out with two different populations of Drosophila melanogaster. The results show a consistent accelerated inbreeding depression for fitness, suggesting synergistic epistasis among deleterious alleles. We also performed computer simulations assuming different possible models of epistasis and mutational parameters for fitness, finding some of them to be compatible with the results observed. Our results suggest that synergistic epistasis for deleterious mutations not only occurs among newly arisen spontaneous or induced mutations, but also among segregating alleles in natural populationsWe acknowledge the support by Uvigo Marine Research Centre funded by the “Excellence in Research (INUGA)” Programme from the Regional Council of Culture, Education and Universities, with co-funding from the European Union through the ERDF Operational Programme Galicia 2014-2020. This work was funded by Agencia Estatal de Investigación (AEI) (CGL2016-75904-C2-1-P), Xunta de Galicia (ED431C 2016-037) and Fondos Feder: “Unha maneira de facer Europa.” SD was founded by a predoctoral (FPI) grant from Ministerio de Economía y Competitividad, SpainS

A simultaneous search for High-z LAEs and LBGs in the SHARDS survey

We have undertaken a comprehensive search for both Lyman Alpha Emitters (LAEs) and Lyman Break Galaxies (LBGs) in the SHARDS Survey of the GOODS-N field. SHARDS is a deep imaging survey, made with the 10.4 m Gran Telescopio Canarias (GTC), employing 25 medium band filters in the range from 500 to 941 nm. This is the first time that both LAEs and LBGs are surveyed simultaneously in a systematic way in a large field. We draw a sample of 1558 sources; 528 of them are LAEs. Most of the sources (1434) show rest-frame UV continua. A minority of them (124) are pure LAEs with virtually no continuum detected in SHARDS. We study these sources from z ∼ 3.35 up to z ∼ 6.8, well into the epoch of reionization. Note that surveys done with just one or two narrow band filters lack the possibility to spot the rest-frame UV continuum present in most of our LAEs. We derive redshifts, Star Formation Rates (SFRs), Lyα Equivalent Widths (EWs) and Luminosity Functions (LFs). Grouping within our sample is also studied, finding 92 pairs or groups of galaxies at the same redshift separated by less than 60 comoving kpc. In addition, we relate 87 and 55 UV-selected objects with two known overdensities at z = 4.05 and z = 5.198, respectively. Finally, we show that surveys made with broad band filters are prone to introduce many unwanted sources (∼20% interlopers), which means that previous studies may be overestimating the calculated LFs, specially at the faint end

Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE

Charge separation relative to the reaction plane in Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm NN}}= 2.76 TeV

Measurements of charge dependent azimuthal correlations with the ALICE detector at the LHC are reported for Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 2.76$ TeV. Two- and three-particle charge-dependent azimuthal correlations in the pseudo-rapidity range $|\eta| < 0.8$ are presented as a function of the collision centrality, particle separation in pseudo-rapidity, and transverse momentum. A clear signal compatible with a charge-dependent separation relative to the reaction plane is observed, which shows little or no collision energy dependence when compared to measurements at RHIC energies. This provides a new insight for understanding the nature of the charge dependent azimuthal correlations observed at RHIC and LHC energies.Comment: 12 pages, 3 captioned figures, authors from page 2 to 6, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/286