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Abstract Glass durability is one of the properties that can be affected by surface treatments such as coatings or chemical attacks. These treatments can be used to reduce the quantities of potentially toxic elements contained in glass that may be released in solution. Five surface treatments were selected: three different coatings (SnO2, TiO2, SiO2) and two acidic attacks (SO2 dealkalization and acid polishing). These treatments were performed on five glass compositions (soda-lime, borosilicate, barium silicate, opal, and lead crystal). Their effects on alteration rates and mechanisms were investigated through a single protocol (acetic acid 4%, 70 °C) simulating accelerated aging conditions for containers of beverages or food. The data collected over 1.3 years showed significant reduction of lead leaching with all treatments except acid polishing. The best reduction factor was obtained with SO2 dealkalization, which also demonstrated beneficial effects towards the retention of Ba by reducing the diffusion of alkalis.

Inhibin is a glycoproteic hormone mostly produced by the gonads. Through a feedback at the pituitary level, it selectively inhibits the release of follicle-stimulating hormone. In mammals, inhibin has been found also in some extragonadal tissues such as placenta, pituitary, adrenal, spleen, kidney, brain and spinal cord. At present, no information is available about the existence of inhibin in reptiles. The aim of the present work is to localise, through immunocytochemical methods, the sites of inhibin production in male lizards during the main phases of the reproductive cycle: the culmination phase (April-June), the early regressive phase (early July), the maximal regressive phase (August) and the winter stasis (January). In the testis, immunostaining is mainly localised in the Leydig cells during the early regressive phase, while it is observed in the Sertoli cells during the maximal regressive phase. In the epididymis, the immunostaining is present only during the reproductive period at the level of secreting cells and inside its ducts. In the adrenal gland, after immunostaining, both chromaffin and steroidogenetic tissues are inhibin-positive during the whole spermatogenetic cycle, though with variable intensity throughout the year: cross-reaction appears more evident from January to April (winter stasis and culmination phase) and weaker in June. However, in captive animals, the reaction persists in chromaffin cells, but disappears in steroidogenetic cells. The functional meaning of the presence of inhibin as a factor in the local regulation of spermatogenesis is discussed.

Inhibin is a glycoproteic hormone mostly produced by the gonads. Through a feedback at the pituitary level, it selectively inhibits the release of follicle-stimulating hormone. In mammals, inhibin has been found also in some extragonadal tissues such as placenta, pituitary, adrenal, spleen, kidney, brain and spinal cord. At present, no information is available about the existence of inhibin in reptiles. The aim of the present work is to localise, through immunocytochemical methods, the sites of inhibin production in male lizards during the main phases of the reproductive cycle: the culmination phase (April-June), the early regressive phase (early July), the maximal regressive phase (August) and the winter stasis (January). In the testis, immunostaining is mainly localised in the Leydig cells during the early regressive phase, while it is observed in the Sertoli cells during the maximal regressive phase. In the epididymis, the immunostaining is present only during the reproductive period at the level of secreting cells and inside its ducts. In the adrenal gland, after immunostaining, both chromaffin and steroidogenetic tissues are inhibin-positive during the whole spermatogenetic cycle, though with variable intensity throughout the year: cross-reaction appears more evident from January to April (winter stasis and culmination phase) and weaker in June. However, in captive animals, the reaction persists in chromaffin cells, but disappears in steroidogenetic cells. The functional meaning of the presence of inhibin as a factor in the local regulation of spermatogenesis is discussed.

Abstract The initial dissolution rate of a series of multicomponent glasses is studied in order to discuss the influence of increasing magnesium content in the glass on this alteration regime and to highlight differences in behavior between calcium- and magnesium-bearing glasses. The application of MD-based topological constraint theory (TCT) is confronted to glass transition temperature (T g ) and initial dissolution rate (r 0) on a glass series containing the main oxides of a French nuclear glass (AVM). In addition, a comparison between a reference magnesium-containing nuclear waste glass, AVMV4 and a proposed derived simplified composition N19M8 is performed regarding r 0 values. Results indicate a similar behavior in this alteration regime for the two glasses, suggesting that this simple glass might be a good analogue to the complex one. Substituting calcium for magnesium decreases the initial dissolution rate by a factor two in the series, while an overall increase of magnesium leads to an increased dissolution rate. Analyses performed with TCT suggests that magnesium environment is better defined than calcium or sodium and may behave as an intermediate species. Finally, a correlation between the number of constraints per atom and T g is established, while the model failed to link structural features to r 0.

Abstract The alteration of a four-oxide alumino-borosilicate glass close to International Simple Glass (ISG) was studied in Si saturation conditions at pH 3, pH 7, and pH 9 using solution and post mortem solid analyses. In particular, the study examined the impact of structural disorder on the glass alteration generated by swift heavy ion irradiation. It is shown that the pre-irradiated glass altered three to four times more than the non-irradiated glass, depending on the pH. This increased alteration can be attributed to two factors: an increased hydrolysis speed of the Si–O–B bonds, which control the glass dissolution under these Si saturation conditions, and a less passivating alteration layer. The latter effect suggests that the glass structural disorder is retained by the first gel formed, which means very low Si atom mobility during alteration. However, gel maturation tends to mitigate the detrimental effect of radiation damages. These results will contribute to the development of a predictive residual rate model.

The analysis of fecal neutral sterols has been improved by use of a highly selective gas-liquid chromatography column packed with SP-2401. This chromatographic column allows separation of cholesterol and cholestanol and delta 5-5 alpha plant sterol homologs without employing silver nitrate thin-layer chromatography. Furthermore, there is no need to derivatize neutral sterols before injection. The main fecal neutral sterols are well resolved; retention times are reproducible; detector response is reproducible, linear, and sensitive to 0.2 micrograms. This method, successfully used for fecal samples, may be suggested as a routine method for the clinical study of cholesterol metabolism.

Abstract Leptospirosis is a global zoonotic disease caused by pathogenic bacteria of the genus Leptospira. We sought to determine if rodents in U.S. Virgin Islands (USVI) are carriers of Leptospira. In total, 140 rodents were sampled, including 112 Mus musculus and 28 Rattus rattus. A positive carrier status was identified for 64/140 (45.7%); 49 (35.0%) were positive by dark-field microscopy, 60 (42.9%) by culture, 63 (45.0%) by fluorescent antibody testing, and 61 (43.6%) by real-time polymerase chain reaction (rtPCR). Molecular typing indicated that 48 isolates were L. borgpetersenii and 3 were L. kirschneri; the remaining nine comprised mixed species. In the single culture-negative sample that was rtPCR positive, genotyping directly from the kidney identified L. interrogans. Serotyping of L. borgpetersenii isolates identified serogroup Ballum and L. kirschneri isolates as serogroup Icterohaemorrhagiae. These results demonstrate that rodents are significant Leptospira carriers and adds to understanding the ecoepidemiology of leptospirosis in USVI.

During 2019-2020, the Virgin Islands Department of Health investigated potential animal reservoirs of Leptospira spp., the bacteria that cause leptospirosis. In this cross-sectional study, we investigated Leptospira spp. exposure and carriage in the small Indian mongoose (Urva auropunctata, syn: Herpestes auropunctatus), an invasive animal species. This study was conducted across the three main islands of the U.S. Virgin Islands (USVI), which are St. Croix, St. Thomas, and St. John. We used the microscopic agglutination test (MAT), fluorescent antibody test (FAT), real-time polymerase chain reaction (lipl32 rt-PCR), and bacterial culture to evaluate serum and kidney specimens and compared the sensitivity, specificity, positive predictive value, and negative predictive value of these laboratory methods. Mongooses (n = 274) were live-trapped at 31 field sites in ten regions across USVI and humanely euthanized for Leptospira spp. testing. Bacterial isolates were sequenced and evaluated for species and phylogenetic analysis using the ppk gene. Anti-Leptospira spp. antibodies were detected in 34% (87/256) of mongooses. Reactions were observed with the following serogroups: Sejroe, Icterohaemorrhagiae, Pyrogenes, Mini, Cynopteri, Australis, Hebdomadis, Autumnalis, Mankarso, Pomona, and Ballum. Of the kidney specimens examined, 5.8% (16/270) were FAT-positive, 10% (27/274) were culture-positive, and 12.4% (34/274) were positive by rt-PCR. Of the Leptospira spp. isolated from mongooses, 25 were L. borgpetersenii, one was L. interrogans, and one was L. kirschneri. Positive predictive values of FAT and rt-PCR testing for predicting successful isolation of Leptospira by culture were 88% and 65%, respectively. The isolation and identification of Leptospira spp. in mongooses highlights the potential role of mongooses as a wildlife reservoir of leptospirosis; mongooses could be a source of Leptospira spp. infections for other wildlife, domestic animals, and humans.

Mongooses, a nonnative species, are a known reservoir of rabies virus in the Caribbean region. A cross-sectional study of mongooses at 41 field sites on the US Virgin Islands of St. Croix, St. John, and St. Thomas captured 312 mongooses (32% capture rate). We determined the absence of rabies virus by antigen testing and rabies virus exposure by antibody testing in mongoose populations on all three islands. USVI is the first Caribbean state to determine freedom-from-rabies for its mongoose populations with a scientifically-led robust cross-sectional study. Ongoing surveillance activities will determine if other domestic and wildlife populations in USVI are rabies-free.

Este trabajo tuvo por objetivo aislar, identificar y caracterizar morfológicamente hongos entomopatógenos presentes en suelos cultivados con yerba mate (Ilex paraguariensis St. Hil.). Se realizó una prospección de hongos entomopatógenos nativos a partir de 40 muestras de suelos cultivados con yerba mate ubicados en la provincia de Misiones, República Argentina, desde mayo de 2008 hasta junio de 2010. Las muestras de suelo se obtuvieron en cercanías de plantas de yerba mate, se aplicó la técnica de dilución seriada en medios de cultivos selectivos. Después de obtenidos los cultivos puros, los hongos fueron caracterizados macroscópica y microscópicamente, y se los identificó mediante el uso de claves taxonómicas específicas. Se aislaron 29 cepas fúngicas pertenecientes a las especies Beauveria bassiana (n = 17), Metarhizium anisopliae (n = 2) y Purpureocillium lilacinum (n = 10).