Maxwell's Equations in the Myers-Perry Geometry

We demonstrate separability of the Maxwell's equations in the Myers-Perry-(A)dS geometry and derive explicit solutions for various polarizations. Application of our construction to the four-dimensional Kerr black hole leads to a new ansatz for the Maxwell field which has significant advantages over the previously known parameterization.Comment: 94 pages. V2: Appendix F added, typos fixe

Cryptosporidium occurrence in ruminants from the North Pioneer mesoregion of Paraná, Brazil

<div><p>Abstract The aim of this study was to investigate the occurrence of Cryptosporidium in cattle and sheep from the North Pioneer mesoregion of the state of Paraná. For this, 317 stool samples were collected from cattle and sheep on 16 properties in six municipalities in the North Pioneer mesoregion of Paraná. For detection of Cryptosporidium species, molecular analysis was performed using nested-PCR techniques targeting the 18S rRNA gene. Of the 37 beef cows and 115 calves analyzed, four (10.8%) and 14 (12.2%), respectively, were positive for Cryptosporidium. Of the 12 cows and 52 calves, one (8.3%) and 14 (26.9%), respectively, were positive for Cryptosporidium; and of the 42 ewes and 59 lambs, six (14.3%) and 12 (20.3%), respectively were positive for Cryptosporidium. Cattle (15.3%) and sheep (17.8%) were both susceptible to infection. All the properties of the municipalities of Assaí, Ibaiti and, Leópolis presented infected animals. The study showed that Cryptosporidium occurs in most municipalities assessed, that dairy calves had a higher risk (Odds Ratio=2,66, p-value=0,018) for infection than beef calves, and that sheep are just as susceptible to infection as are cattle, and that further Cryptosporidium studies are developed.</p></div

Spatial and simultaneous representative seroprevalence of anti-<i>Toxoplasma gondii</i> antibodies in owners and their domiciled dogs in a major city of southern Brazil

<div><p>Toxoplasmosis, caused by <i>Toxoplasma gondii</i>, has traditionally been considered an important water and foodborne protozoonosis with important public health considerations. Although felids play a well-established role as definitive hosts, canine epidemiological involvement in the parasite’s life cycle remains questionable and controversial. The increasing closeness of the human-dog bond, particularly seen in urban settings, has been recognized as a historically unprecedented worldwide movement. Sharing daily lives in the same households, dogs may be exposed to similar associated risks of <i>T</i>. <i>gondii</i> infection as their owners. Thus, epidemiological assessment of the intra-domiciled environment, especially among socio-economically different human populations, may provide novel information regarding the actual role of dogs in animal and human toxoplasmosis. Despite spatial approaches being recently used for other water and foodborne diseases, no study has been conducted on the simultaneous spatial seroprevalence of both human and animal IgG anti-<i>T</i>. <i>gondii</i> antibodies in urban areas of major cities. Accordingly, the aim of the present study was to assess the seroprevalence and associated variables of <i>Toxoplasma</i> infection in owners and their domiciled dogs in Londrina, southern Brazil. Human and canine seroprevalence rates and variables associated with seroprevalence were investigated through representative random sampling among 564 households, which included 597 owners and 729 dogs. Overall, statistically significant differences between the seroprevalence of human and dog anti-<i>T</i>. <i>gondii</i> antibodies were found by Immunofluorescence Antibody Testing in 248/597 (41.54%) owners and 119/729 (16.32%) dogs. Through multiple analysis, significant concomitant variables for seropositivity of household individuals (people and dogs) were determined, including public sewer service, yard cleaning frequency, and having a dirty yard. Although no statistically significant multiple logistic model was observed among owners, univariate analysis detected associations with monthly income, soil contact, and occupation. Among dogs, the absence of other dogs and the absence of a dirty yard were concomitant significantly protective associated factors. Age differences between seropositive and seronegative individuals was significant only for human beings, with the median age of negative individuals significantly higher than positive individuals. Although no spatial clusters were identified for humans or residences, a significant cluster was identified for dogs. In conclusion, characteristics of urban toxoplasmosis may include significantly higher owner seroprevalence than their owned dogs, with canine seroprevalence directly associated with having more dogs and a dirty backyard, and spatial differences in both human and dog exposures. Although not a good indicator for human foodborne diseases, dogs may be a reliable sentinel for environmental infection. Moreover, such a holistic approach may provide crucial information for more focused prevention and monitoring programs, particularly in households with multiple pets and trash-filled backyards.</p></div

The first study of molecular prevalence and species characterization of Cryptosporidium in free-range chicken (Gallus gallus domesticus) from Brazil

<div><p>Abstract Rearing free-range chicken is based on grazing feeding patterns, and these animals could be potential environmental contaminants of Cryptosporidium oocysts for humans and other animals. Therefore, the present study aimed to evaluate the molecular prevalence of Cryptosporidium spp. in free-range chickens from Brazil. A total of 351 fecal samples from chickens were examined from 20 farms. For detection of Cryptosporidium spp., 18S rRNA gene fragments were amplified using a nested PCR reaction. Positive samples were sent for sequencing. The overall prevalence of Cryptosporidium was 25.6% (95% CI = 21.2% - 30.6%). Sequencing of the amplified fragments allowed for the identification of three species: C. meleagridis in 57 (62.6%), C. baileyi in 15 (16.4%), C. parvum in 3 (3.2%) samples, and a new Cryptosporidium genotype (C. genotype BrPR1) in 3 (3.2%) samples. Cryptosporidium genotype BrPR1 has not yet been classified as a species, and its host spectrum is not known. Cryptosporidium, including zoonotic species, exists at a high prevalence in free-range chickens within the region studied.</p></div

Histogram of age for positive and negative owners for <i>T</i>. <i>gondii</i> serology in the urban area of Londrina, from July 2015 to July 2016.

<p>Histogram of age for positive and negative owners for <i>T</i>. <i>gondii</i> serology in the urban area of Londrina, from July 2015 to July 2016.</p

Yesple distribution and relative spatial risk for positive and negative humans, dogs and households (human and/or dogs) for <i>T</i>. <i>gondii</i> infection in the urban area of Londrina, from July 2015 to July 2016.

<p>Yesple distribution and relative spatial risk for positive and negative humans, dogs and households (human and/or dogs) for <i>T</i>. <i>gondii</i> infection in the urban area of Londrina, from July 2015 to July 2016.</p

Histogram of age for positive and negative dogs for <i>T</i>. <i>gondii</i> serology in the urban area of Londrina, from July 2015 to July 2016.

<p>Histogram of age for positive and negative dogs for <i>T</i>. <i>gondii</i> serology in the urban area of Londrina, from July 2015 to July 2016.</p

Kernel density analyses of human, dog and household (human and/or dogs) positivity and negativity for <i>T</i>. <i>gondii</i> infection in the urban area of Londrina, from July 2015 to July 2016.

<p>Kernel density analyses of human, dog and household (human and/or dogs) positivity and negativity for <i>T</i>. <i>gondii</i> infection in the urban area of Londrina, from July 2015 to July 2016.</p

<i>Cryptosporidium</i> spp. and <i>Giardia</i> spp. in feces and water and the associated exposure factors on dairy farms

<div><p>The aims of this study were to verify the prevalence of <i>Cryptosporidium</i> spp. and <i>Giardia</i> spp. in animal feces and drinking water on dairy farms and to identify a possible relation between the exposure factors and the presence of these parasites. Fecal samples from cattle and humans and water samples were collected on dairy farms in Paraná, Brazil. Analysis of (oo)cysts in the feces was performed by the modified Ziehl-Neelsen staining and centrifugal flotation in zinc sulfate. Test-positive samples were subjected to nested PCR amplification of <i>the 18SSU</i> ribosomal RNA gene for identification of <i>Cryptosporidium</i> and <i>Giardia</i> and of the <i>gp60</i> gene for subtyping of <i>Cryptosporidium</i>. Microbiological analysis of water was carried out by the multiple-tube method and by means of a chromogenic substrate, and parasitological analysis was performed on 31 samples by direct immunofluorescence and nested PCR of the genes mentioned above. Identification of the species of <i>Cryptosporidium</i> was performed by sequencing and PCR with analysis of restriction fragment length polymorphisms. The prevalence of <i>Giardia</i> and <i>Cryptosporidium</i> was higher in calves than in adults. Among the samples of cattle feces, <i>Cryptosporidium parvum</i> was identified in 41 (64%), <i>C</i>. <i>ryanae</i> in eight (12.5%), <i>C</i>. <i>bovis</i> in four (6.3%), <i>C</i>. <i>andersoni</i> in five (7.8%), and a mixed infection in 20 samples (31.3%). These parasites were not identified in the samples of human feces. Thermotolerant coliform bacteria were identified in 25 samples of water (45.5%). <i>Giardia duodenalis</i> and <i>C</i>. <i>parvum</i> were identified in three water samples. The <i>gp60</i> gene analysis of <i>C</i>. <i>parvum</i> isolates revealed the presence of two strains (IIaA20G1R1 and IIaA17G2R2) in the fecal samples and one (IIaA17G2R1) in the water samples. The presence of coliforms was associated with the water source, structure and degradation of springs, rain, and turbidity. The prevalence of protozoa was higher in calves up to six months of age. <i>C</i>. <i>parvum</i> and <i>G</i>. <i>duodenalis</i> were identified in the water of dairy farms, as were thermotolerant coliforms; these findings point to the need for guidance on handling of animals, preservation of water sources, and water treatment.</p></div