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The olive fly, Bactrocera oleae (Rossi, 1790), is the major insect pest of olives attacking both cultivated and wild olive. Bactrocera oleae carries a primary and vertically transmitted symbiont, the bacterium Candidatus Erwinia dacicola. As any primary symbiont, it plays an important role in the reproduction and lifespan of the fly. The genetic 16S rRNA diversity of the primary symbiont and the mitochondrial haplotype variation of the insect host were simultaneously examined in 54 olive fly populations. The aim was to unravel the biogeographic patterns of this economically relevant host-bacteria interaction across a wide distribution area. Three symbiont haplotypes were identified. The primary symbiont showed a lower haplotype diversity than that of its host, a characteristic indicative of a long-term interaction. A significant genetic and geographic association between host and primary symbiont was observed, with an East-West genetic differentiation pattern in the Mediterranean basin, coinciding with the historical genetic distribution of the olive tree. The study shows promise, informing and aiding the development of future tools for the control of the olive fly. [ABSTRACT FROM AUTHOR]

Hypopi of Lardoglyphus zacheriOudemans, 1927 were found attached to larder beetles (Coleoptera: Dermestidae) colonising experimental pig carcasses in the Parque Natural Aiako Harria, Errenteria, Gipuzkoa, northern Spain. Five pig carcasses were used for a study of arthropod colonisation during the decomposition process, and the experiment lasted 88 days (from July to October 2010). Hypopi were found when the carcasses commenced reduction to dried remains, on day 29 (August 24), and were attached to Dermestes frischi Kugelann, 1792 and to D. undulatus Brahm, 1790, all collected on the same carcass (carcass 3, C3). No more lardoglyphid mites were detected from August 29 to the last day of sampling, October 22 2010. This is the first record of Lardoglyphus hypopi on D. undulatus and of L. zacheri from the Iberian Peninsula. [ABSTRACT FROM AUTHOR]

This study reports for the first time the use of soil micro-invertebrates, mites, as trace evidence to localise buried objects such as money. The case relates to a crime in Germany, where a large sum of banknotes had been hidden in an unknown location, likely abroad. In 2016, part of the money (approx. €500,000 in €500 value notes) was confiscated by the police. After analysis in the forensic lab, it was discovered that the notes were covered with small particles of a sort of debris, later identified as specimens of Rhizoglyphus howensis Manson, a non-European, nor Mediterranean species of root or bulb mites (Acaridae: Rhizoglyphinae). The restricted biogeographic distribution of R. howensis, originated in unspoiled forest soil in the Australasian region, limited the search for the money to the areas visited by the perpetrators during their trips to the region. Rhizoglyphus howensis biology provided further clues on the whereabouts of the banknotes, as they are specialist plant feeders, exclusively feeding on seeds of palm trees and on roots of Quercus patula in the Australasian region. This report aims to highlight the importance of the correct identification of the microscopic organisms associated with a crime scene and the immediate retrieval of micro-invertebrate trace evidence. This is the first record of R. howensis from Europe, and from banknotes. [ABSTRACT FROM AUTHOR]

The effect of scalding temperature of the curd, the inclusion of a washing step, and the pH at whey drainage on plasmin and coagulant activities were assessed in a minicurd model of young hard cooked cheese. The variables were tested as follows: draining pH was assayed at 3 levels (4.6, 5.6, and 6.4), curd scalding temperature was tested at 50 and 56°C, and washing of the curd was examined at 2 levels (no washing step, and the replacement of the whey by water). Increase in pH at whey drainage and washing of the curd had a positive effect on plasmin activity, which was also evidenced by compatible changes in soluble peptide profiles. No effect of increased cooking temperature was found on plasmin activity. Plasminogen activation was not verified in any treatment. As for coagulant, lower pH values at whey drainage and a decrease in curd cooking temperature increased its activity; washing of the curd showed no influence on coagulant residual activity. These results were consistent with proteolysis described by peptide profiles, electrophoresis, and soluble nitrogen fractions. [ABSTRACT FROM AUTHOR]

The aim of this study was to propose and validate a new minicurd model of young hard cheese. Curd particles and whey obtained from conventional cheese making of Reggianito Argentino were separated and frozen. Then, both fractions were thawed and the mixture of whey and curds was reconstituted, from which minicurds were made on the laboratory scale. Repeatability and the effect of freezing on minicurd composition were investigated by assessing pH, protein and moisture contents, sodium chloride content, and total thermophilic lactic flora counts. Good repeatability was achieved, and no significant differences were found between minicurds made from fresh compared with frozen materials. Composition of the minicurd was appropriate for modeling Reggianito Argentino cheese. [ABSTRACT FROM AUTHOR]

Body size ( BS) varies in response to several selective pressures. In ectotherms, thermal inertia may affect thermoregulation, since larger BSs increase heat conservation as Bergmann originally stipulated for endotherms. However, Bergmann's rule is controversial in ectotherms. The heat balance hypothesis states that ectotherms' thermoregulatory capability is relevant for trends in BS. In cold climates, larger BSs would be advantageous for small thermoregulating ectotherms, by increasing heat conservation. However, BS implies a delaying effect on heating too; therefore, ectotherms may need another trait to compensate the later effect. Thermal melanism hypothesis posits that melanism increases heat gain, and may be adaptive for animals inhabiting cold climates. We propose that the higher solar radiation absorption from increased melanism may be such a compensatory trait. We expect BS and melanism to increase with latitude in response to seasonal temperatures and solar radiation. To test this, we studied the monophyletic L iolaemus goetschi group of lizard species across its 2200 km (32-48° S latitude) range. We used phylogenetically informed analyses to study geographic variation of BS and melanism (dorsal, ventral and total) in relation to temperatures, thermal amplitude, cloudiness and net solar radiation. Our results show that lizards' BS increases latitudinally in relation to thermal amplitude and temperature. Only ventral melanism varied latitudinally, but all melanism variables varied in response to cloudiness and net radiation. The relationship between BS and melanism was significant and positive in all cases. We suggest thermal inertia may be a fair candidate mechanism explaining geographic variation in BS (heat balance hypothesis), while melanism may influence heat gain according to the thermal melanism hypothesis. However, it remains unclear why latitudinal variation is related to ventral instead of dorsal melanism, and further investigation is needed to clarify the relationship between BS and melanism in light of cold climates. [ABSTRACT FROM AUTHOR]

The adipose tissue has detrimental effects on growth hormone secretion, even in the absence of obesity. The majority of previous studies have shown an inverse relationship between fat mass and the growth hormone response to several stimulation tests in adults and in children. The contribution of body fat mass on growth hormone response to provocative tests during the transition age is not known . We analyzed the GHIGF1 axis by GHRH-arginine test in 30 healthy adolescents with normal stature during the transition period from 14 to 18 years. All subjects underwent body composition analysis by dualenergy X-ray absorptiometry (DXA). We found that total body fat mass was inversely correlated with peak GH to provocative test (r = - 0.6, p = 0.004). GH deficiency was shown in 2 of our healthy patients if diagnosis was based on GH peak below 19 μg/l. Both children who failed the GHRH-arginine were overweight (BMI for age above 85th percentile). However, their GH status was normal when assessed by insulin tolerance test. Multivariate analysis demonstrated strong correlation between peak stimulated GH and measures of body adiposity, including body mass index and fat mass index, with the latter showing the most important effect on GH secretion . Fat mass index alone explained 34.5 % of the variability in peak GH. This study has shown for the first time that during the transition period, GH response to GHRH-arginine test is strongly influenced by body composition, and cutoff values appropriate for overweight and obese adolescents are needed. Supporting information available online at http:// www.thieme-connect.de/ejournals/toc/hmr. [ABSTRACT FROM AUTHOR]

Abstract: ‘Candidatus Cardinium’ is an intracellular endosymbiont or parasite frequently occurring in invertebrates including mites and ticks. In this work we report Cardinium bacteria in Astigmata mites and explore their incidence in synanthropic species. Amplification of a 776bp bacterial 16S rRNA gene fragment, using specific primers, enabled identification of closely related Cardinium sequences in 13 laboratory-reared populations of mites. In addition, Cardinium sequences were identified in three wild mite populations. Large scale screening of these populations showed 100% prevalence of Cardinium, representing the highest incidence compared to other major Chelicerate groups. [Copyright &y& Elsevier]

Reggianito is the most important variety among the Argentinean hard cheeses. During its ripening period several biochemical reactions of proteins and fat are responsible for its final sensory characteristics. The fat transformations, in a first step, produce free fatty acids (FFA). In the present work, the FFA profile from C6:0 C18:2 during ripening was evaluated. Reggianito cheeses were produced with a "wild" whey starter and with selected strains of Lactobacillus helveticus isolated from natural whey. Information from FFA profiles was processed by Principal Component Analysis (PCA) and Discriminant Analysis (DA). Despite the fact that FFA levels grew continuously during ripening, no differences were found among cheeses produced with different starters. Sensory analyses did not show differences among the different cheeses produced. AII cheeses were of satisfactory sensory quality. Results from this study are important for an increased knowledge of the ripening process of Reggianito cheese, considering the scarce information currently existing on this subject. At the same time, the substitution of a natural whey starter for a selected strain starter appears to be a possible advantage in order to improve and to standardize the quality of the cheese. [ABSTRACT FROM AUTHOR]

The first mycetome was discovered more than 340 yr ago in the human louse. Despite the remarkable biology and medical and social importance of human lice, its primary endosymbiont has eluded identification and characterization. Here, we report the host-symbiont interaction of the mycetomic bacterium of the head louse Pediculus humanus capitis and the body louse P. h. humanus. The endosymbiont represents a new bacterial lineage in the γ-Proteobacteria. Its closest sequenced relative is Arsenophonus nasoniae, from which it differs by more than 10%. A. nasoniae is a male-killing endosymbiont of jewel wasps. Using microdissection and multiphoton confocal microscopy, we show the remarkable interaction of this bacterium with its host. This endosymbiont is unique because it occupies sequentially four different mycetomes during the development of its host, undergoes three cycles of proliferation, changes in length from 2-4 µm to more than 100 µm, and has two extracellular migrations, during one of which the endosymbionts have to outrun its host's immune cells. The host and its symbiont have evolved one of the most complex interactions: two provisional or transitory mycetomes, a main mycetome and a paired filial mycetome. Despite the close relatedness of body and head lice, differences are present in the mycetomic provisioning and the immunological response. [ABSTRACT FROM AUTHOR]

Reggianito Argentino cheeses were manufactured with mixed strains of Lactobacillus helveticus cultured in free viable bacteria whey. As controls, cheeses with natural whey starter were made. Gross composition of cheeses did not differ significantly. The number of total termophilic lactic acid bacteria at the end of ripening was near 107 CFU/g, but when the strain Lh 209 was present in the mixture, this number was 106 CFU/g. Soluble nitrogen at pH 4.6 did not differ between control and experimental cheeses, but soluble nitrogen in tricloroacetic acid 12% and phosphotungstic acid 2.5% showed significant differences at the end of ripening, being higher the values when the strain Lh 209 was present in the mixture. Electrophoretic profiles for control and experimental cheeses were very similar at 0, 90 and 180 days of ripening. An increase in the acid degree value of fat during ripening was noticeable indicating a lipolytic activity in the cheese matrix that was similar for the different strains mixtures. Results from sensory analysis did not show differences among the cheeses of these tests. Despite some differences in the production tricloroacetic and phosphotungstic acid soluble nitrogen were observed for mixtures in which Lh 209 was present, all cheeses were good quality Reggianito Argentino cheeses. These results open and interesting prospective for the use of selected strains culture in whey in substitution of natural whey. [ABSTRACT FROM AUTHOR]

Background: At the turn of the 19th century the first observations of a female-biased sex ratio in broods and populations of the head louse, Pediculus humanus capitis, had been reported. A study by Buxton in 1940 on the sex ratio of lice on prisoners in Ceylon is still today the subject of reanalyses. This sex ratio distortion had been detected in ten different countries. In the last sixty years no new data have been collected, especially on scalp infestations under economically and socially more developed conditions. Results: Here we report a female bias of head lice in a survey of 480 school children in Argentina. This bias is independent of the intensity of the pediculosis, which makes local mate competition highly unlikely as the source of the aberrant sex ratio; however, other possible adaptive mechanisms cannot be discounted. These lice as well as lice from pupils in Britain were carrying several strains of the endosymbiotic bacterium Wolbachia pipientis, one of the most wide spread intracellular sex ratio distorters. Similar Wolbachia strains are also present in the pig louse, Haematopinus suis, suggesting that this endosymbiont might have a marked influence on the biology of the whole order. The presence of a related obligate nutritional bacterium in lice prevents the investigation of a causal link between sex ratio and endosymbionts. Conclusions: Regardless of its origin, this sex ratio distortion in head lice that has been reported world wide, is stable over time and is a remarkable deviation from the stability of frequencydependent selection of Fisher's sex ratio. A female bias first reported in 1898 is still present over a hundred years and a thousand generations later. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tyrophagus putrescentiae (mould mite) is ubiquitous; its DNA contaminates sequences of other organisms in public databases. • Symbiotic bacteria are diverse, and aid the mite's success as a trophic generalist. • Tyrophagus putrescentiae is host to a Gram-negative bacterium, Wolbachia (supergroup Q) • Wolbachia supergroup Q is a basal, mite-specific lineage. • No horizontal gene transfer events from bacteria or fungi were found. Tyrophagus putrescentiae (mould mite) is a global, microscopic trophic generalist that commonly occurs in various human-created habitats, causing allergies and damaging stored food. Its ubiquity and extraordinary ability to penetrate research samples or cultures through air currents or by active walking through tights spaces (such as treads of screw caps) may lead to sample contamination and introduction of its DNA to research materials in the laboratory. This prompts a thorough investigation into potential sequence contamination in public genomic databases. The trophic success of T. putrescentiae is primarily attributed to the symbiotic bacteria housed in specialized internal mite structures, facilitating adaptation to varied nutritional niches. However, recent work suggests that horizontal transfer of bacterial/fungal genes related to nutritional functionality may also contribute to the mite's trophic versatility. This aspect requires independent confirmation. Additionally, T. putrescentiae harbors an uncharacterized and genetically divergent bacterium, Wolbachia , displaying blocking and microbiome-modifying effects. The phylogenomic position and supergroup assignment of this bacterium are unknown. Here, we sequenced and assembled the T. putrescentiae genome, analyzed its microbiome, and performed detailed phylogenomic analyses of the mite-specific Wolbachia. We show that T. putrescentiae DNA is a substantial source of contamination of research samples. Its DNA may inadvertently be co-extracted with the DNA of the target organism, eventually leading to sequence contamination in public databases. We identified a diversity of bacterial species associated with T. putrescentiae , including those capable of rapidly developing antibiotic resistance, such as Escherichia coli. Despite the presence of diverse bacterial communities in T. putrescentiae , we did not detect any recent horizontal gene transfers in this mite species and/or in astigmatid (domestic) mites in general. Our phylogenomic analysis of Wolbachia recovered a basal, mite-specific lineage (supergroup Q) represented by two Wolbachia spp. from the mould mite and a gall-inducing plant mite. Fluorescence in situ hybridization confirmed the presence of Wolbachia inside the mould mite. The discovery of an early derivative Wolbachia lineage (supergroup Q) in two phylogenetically unrelated and ecologically dissimilar mites suggests that this endosymbiotic bacterial lineage formed a long-term association with mites. This finding provides a unique insight into the early evolution and host associations of Wolbachia. Further discoveries of Wolbachia diversity in acariform mites are anticipated. [ABSTRACT FROM AUTHOR]

The brown marmorated stink bug Halyomorpha halys (Stål) is a globally invasive species that harbours the primary bacterial symbiont 'Candidatus Pantoea carbekii'. In this work, P. carbekii was used as another genetic marker to investigate the biodiversity and biogeographical patterns of this important pest, in native and newly invaded areas, especially in Italy. The correlation between the genetic structure of the symbiont and that of its host was studied through the analyses of one bacterial and one host marker, the putative pseudogene ΔybgF and the mitochondrial gene COI, respectively. As a result, five new P. carbekii haplotypes were identified, and an association pattern between host-symbiont haplotypes was observed. Host species showed higher haplotype diversity than symbiont, which can be expected in a long term host-symbiont association. Populations from the north-eastern Italy showed the highest values of genetic diversity for both markers, highlighting that this particular Italian area could be the result of multiple ongoing introductions. Moreover, some of the symbiont-host haplotypes observed were shared only by populations from north-eastern Italy and native areas, especially Japan, suggesting further introductions from this native country to Italy. Overall, our findings improve the understanding of the potential origin of multiple accidental introductions of H. halys in Italy. [ABSTRACT FROM AUTHOR]

This article discusses a study on the effect of Rickettsia as obligate and mycetomic bacteria. The researchers investigated the diversity of endosymionts and their relationship to host development in parthenogenetic book lice. They then examined the complexity of the evolution of symbiotic and pathogenic interactions. Moreover, the researchers questioned whether they could observe transitional stages of adaptation in the ontogeny of a single individual host between extracellular bacteria and organ-forming bacteria.

In the present work we report on Raman study of Ba0.77Ca0.23TiO3 crystals in the temperature region between 12 K-300 K. We believed to gain insight on the role of Ca admixture, and search manifestations of the possible low temperature tetragonal-orthorhombic phase transition. A special attention was paid to the temperature evolution of Al and E components of the Γ15 modes. Signatures of the presence of CaTiO3 modes are evidenced at around 100 cm-1. The Raman data give no clear indications of the soft mode driven low temperature phase transitions presence, at least down to 12 K, revealing, however, increasing of disordering at cooling. [ABSTRACT FROM AUTHOR]

Evolutionary transitions in life‐history strategies, such as the shift from egg‐laying to live birth (viviparity) are of great interest to evolutionary biologists. In squamate reptiles, several hypotheses have been proposed to explain viviparity including the cold climate hypothesis, maternal manipulation hypothesis, hypoxia hypothesis, and several others. We used two approaches: first we studied 45 species of Liolaemus, a genus where nearly 50% of species are viviparous, using a diverse ecophysiological dataset to examine the cold climate and maternal manipulation hypotheses. We collected environmental thermal data (accounting for elevational differences among species), physiological traits including preferred body temperature and its coefficient of variation as an indicator of precision in thermoregulation. Additionally, we collected standard metabolic rates for 23 of the 45 species. In one clade (the darwinii group of species) with both reproductive modes, we ran our second approach. We tested for differences in thermal physiology and metabolic rates between viviparous and oviparous species during pregnancy and non‐pregnancy periods. The cold climate hypothesis received strong support because viviparous species occur in sites with colder air temperatures (including areas at both higher elevations and latitudes) compared with oviparous species. Our detailed analysis showed that the maternal manipulation hypothesis also is supported; pregnant viviparous females show lower variation in their selected temperature. Our evidence suggests that the Andean orogeny is likely to have played a key role in the diversification of Liolaemus lizards and the evolution of viviparity in this clade may have been driven by a variety of physiological advantages accrued at different stages of embryogenesis and over evolutionary time. Thus, historical climate changes may have led to egg retention and may have been accompanied by other adaptations such as thermoregulation precision. [ABSTRACT FROM AUTHOR]

Burial of a cadaver results in a slower decomposition rate, due to more stable below‐ground temperatures and restricted access to necrophagous insects. In such circumstances, analysis of the soil mesofauna, with emphasis on mites (Acari) may be more valuable in time‐of‐death estimations. The production of volatile organic compounds of cadaveric decay results in changes, especially in the soil pH, which in turn would affect the abundance and diversity of the associated mites. In general, the effects of decomposition and the consequently altered pH levels on the abundance of mites in shallow graves, as well as the effects of fluctuating above‐ground environmental parameters (temperature, relative humidity, and precipitation) remain unknown. Here, we found that the decay of three pig cadavers buried in shallow graves (<30 cm below) caused a significant increase in the soil pH throughout decomposition, from neutral to alkaline. Cadaver decay attracted an abundance of mites: with 300 mites collected from the three pig cadavers compared to 129 from the control soil samples at the same depth. Mites rapidly became more abundant in cadaver‐associated soils than in control soils after the fresh stage. Increasing soil pH had a positive impact on the abundance of mites in graves and there was a significant interaction between cadaver body temperature and soil pH. Above‐ground fluctuations in temperature, relative humidity, and precipitation were found to have no significant direct effect on mite abundance in grave or control soils. [ABSTRACT FROM AUTHOR]

The genus Xenanoetus Mahunka, 1969, only described by the hypopial stage, is characterised by an enlarged gnathosoma, the presence of double claws in legs I, II and III in addition to remarkably broadened femur and genu of legs I and II, particularly visible in lateral view. Only five species from this genus have been described and they are all from the northern hemisphere. Hypopi are generally found as phoretic on Sphaeroceridae flies and Hydrophilidae beetles. Until present, hypopi of the species Xenanoetus grandiceps have only been reported in Mongolia, described by Mahunka in 1973. Xenanoetus grandiceps is characterised by the presence of a pair of arches pointing anteriorly in the posterior part of the gnathosoma. Here we report for the first time X. grandiceps in Spain, and for the second time X. vestigialis. Both species were found in association with carcass remains, as phoretic on lesser dung flies (Sphaeroceridae), which were collected in a mixed deciduous forest near the Atlantic coast. Additional new information on morphological characteristics of these Xenanoetus species, as well as habitat requirements and biology are presented in this report. [ABSTRACT FROM AUTHOR]

Microorganisms present in mosquitoes and their interactions are key factors affecting insect development. Among them, Wolbachia is closely associated with the host and affects several fitness parameters. In this study, the bacterial and fungal microbiota from two laboratory Culex quinquefasciatus isolines (wild type and tetracycline-cured) were characterized by metagenome amplicon sequencing of the ITS2 and 16S rRNA genes at different developmental stages and feeding conditions. We identified 572 bacterial and 61 fungal OTUs. Both isolines presented variable bacterial communities and different trends in the distribution of diversity among the groups. The lowest bacterial richness was detected in sugar-fed adults of the cured isoline, whereas fungal richness was highly reduced in blood-fed mosquitoes. Beta diversity analysis indicated that isolines are an important factor in the differentiation of mosquito bacterial communities. Considering composition, Penicillium was the dominant fungal genus, whereas Wolbachia dominance was inversely related to that of Enterobacteria (mainly Thorsellia and Serratia). This study provides a more complete overview of the mosquito microbiome, emphasizing specific highly abundant components that should be considered in microorganism manipulation approaches to control vector-borne diseases. [ABSTRACT FROM AUTHOR]

Feeding state of animals modulates the antipredator response and could affect the acquisition of new information related to predation risk. Tadpoles commonly decrease locomotor activity as an antipredator response. We performed laboratory assays to study whether an associative learning process to recognize predation risk can be modulated by the feeding state of Pleurodema thaul tadpoles. A group of tadpoles were fed ad libitum and a second group was deprived of food for 36 h prior to the learning acquisition phase. In the acquisition phase a half of tadpoles from each feeding treatment was conditioned by exposition to amphipod injury cues paired with conspecific injury ones (Paired group). The remaining tadpoles received the same cues as those presented to the Paired group but separated 4 h in time (Control group). At the end of the acquisition phase all tadpoles were fed ad libitum and two days later we evaluated changes in tadpoles' activity when they were exposed to amphipod cues. Our results showed that tadpoles in the Paired group that were fed ad libitum prior to acquisition phase decreased their activity when exposed to cues from injured amphipods, but starved tadpoles did not decrease their activity. Starved tadpoles apparently do not generate any association between conspecific and amphipod cues as fed tadpoles do. Our results provide important information regarding how the feeding state of tadpoles may interfere with the acquisition of learning and affect, for example, early detection of predation risk. [ABSTRACT FROM AUTHOR]

Many studies about the influence of Lactococcus lactis on cheese flavour have been reported, while the impact of mesophilic lactobacilli and Streptococcus thermophilus, either as single or mixed cultures, have been less studied. The ability of Lactobacillus paracasei 90, Lb. casei 72 (INLAIN collection) and S. thermophilus 2 (commercial strain) to produce flavour-related biochemical changes, as single or mixed (lactobacilli + streptococci) cultures, was assessed in a cheese model. These three strains, with different activities of glutamate dehydrogenase (GDH) and aminotransferases (AT), were incubated (14d/37 °C) alone or in mixed cultures in a cheese model consisting of a sterile extract of a fresh cheese. Mesophilic lactobacilli showed fermentation of carbohydrates, an increase of peptidolysis and production of volatile compounds that were correlated with their AT activities. In addition, these strains also produced completely different profiles of the amino acceptor compounds: pyruvate and α-ketoglutarate. S. thermophilus 2 increased the level of α-ketoglutarate due to its high GDH activity, but its contribution to flavour compound production was negligible; small additional changes existed when S. thermophilus 2 was mixed with the lactobacilli. Biochemical changes leading to flavour formation were mainly due to the activity of lactobacilli. Our results suggest that the AT profile and the peptidolytic activity of each strain influenced the volatilome of the extracts during incubation. So, both lactobacilli strains could be used as adjunct cultures in cheeses to increase/diversify the flavour, but more studies are needed to deepen the knowledge about the potential of S. thermophilus 2 for the production of flavour compounds. [ABSTRACT FROM AUTHOR]

Culex pipiens is the most cosmopolitan mosquito of the Pipiens Assemblage. By studying the nature of interactions between this species and microorganisms common to its breeding environment we can unravel important pitfalls encountered during development. We tested the survival rate of larval stages, pupae and adults of a Cx. pipiens colony exposed to a variety of microorganisms in laboratory conditions and assessed the transmission to offspring (F1) by those organisms that secured development up to adulthood. Three complementary experiments were designed to: 1) explore the nutritional value of yeasts and other microorganisms during Cx. pipiens development; 2) elucidate the transstadial transmission of yeast to the host offspring; and 3) to examine the relevance of all these microorganisms in female choice for oviposition-substratum. The yeast Saccharomyces cerevisiae proved to be the most nutritional diet, but despite showing the highest survival rates, vertical transmission to F1 was never confirmed. In addition, during the oviposition trials, none of the gravid females was attracted to the yeast substratum. Notably, the two native bacterial strains, Klebsiella sp. and Aeromonas sp., were the preferred oviposition media, the same two bacteria that managed to feed neonates until molting into 2nd instar larvae. Our results not only suggest that Klebsiella sp. or Aeromonas sp. serve as attractants for oviposition habitat selection, but also nurture the most fragile instar, L1, to assure molting into a more resilient stage, L2, while yeast proves to be the most supportive diet for completing development. These experiments unearthed survival traits that might be considered in the future development of strategies of Cx. pipiens control. These studies can be extended to other members of the Pipiens Assemblage. [ABSTRACT FROM AUTHOR]

Movement makes prey more vulnerable to predators. Antipredator responses usually have associated costs such as reduced feeding activity, and decisions made under predation risk may be affected by the feeding state of the prey. In this study, we evaluated whether food regime influences antipredator behavioural responses of Pleurodema thaul tadpoles (diet treatment) before adding food or water (incentive treatment) while the tadpoles were exposed to alarm cues. Under predation risk, normally fed tadpoles showed decreased overall activity, whereas poorly fed tadpoles spent more time feeding after food was provided. Tadpoles in all treatments decreased their swimming activity but not their feeding activity. Our study showed that swimming behaviour was more sensitive to predation risk than feeding behaviour. We suggest that the motivational state of tadpoles under different environmental conditions should be considered when behavioural patterns are analysed to understand short-term trade-offs between foraging requirements and predator avoidance. [ABSTRACT FROM AUTHOR]

In this work, two levels of addition of microparticulated whey protein (MWP) and whey protein concentrate 35% (WPC35) were used for designing semi-skim (∼1.1 g 100 g−1), high-protein yoghurts (≥7 g 100 g−1). Acidification rate, gel formation, carbohydrates, organic acids, volatile compounds, structural and textural aspects, physicochemical and microbial composition, were assessed. Differences were detected in gel formation by Optigraph® (onset of gelation occurred at lower pH for yoghurts with MWP), but similar fermentation times were observed in every case. Higher firmness, consistency and apparent viscosity were found for yoghurts with WPC35, but some lumps were seen when using the highest level of addition. CLSM images revealed different patterns that may support structural differences; also, ingredient's particle size observed by SEM were correlated with the ordering of the protein network. Relevant flavour compounds, like acetaldehyde, acetoin, and diacetyl, were higher in yoghurts with MWP, while ketones predominated in yoghurts with WPC35. • Whey protein ingredients were satisfactory used to formulate high-protein yoghurts. • Different whey protein powders conducted to different results in yoghurts features. • Microparticulated whey protein improved structural and flavour compounds in yoghurt. • Whey protein concentrate at a certain level resulted in a lumpy yoghurt. [ABSTRACT FROM AUTHOR]

This article provides information on the distribution of Aedes aegypti, a mosquito species that transmits dengue and yellow fever viruses. It explains that A. aegypti originated in West Africa and migrated to the Americas in the 15th century. The article discusses the adaptation of A. aegypti to human environments and its ability to breed in various water storage containers. It also mentions the recent increase in dengue cases in Argentina and the potential role of human transportation in the spread of A. aegypti. The study conducted in this article focuses on sampling mosquito larvae and pupae in towns along major highways in Argentina to understand the current distribution of A. aegypti in the region. The study found Aedes aegypti larvae in flowerpots and tire-repair stations, indicating the establishment of a natural population in these areas. The study suggests that the mosquitoes are likely moving through passive dispersal along major highways. The expansion of Aedes aegypti into new areas, combined with the presence of different dengue serotypes, highlights the need for urgent and responsible actions to control the vector and prevent further spread. [Extracted from the article]

The article reports on the colonization of Aedes aegypti in Argentina. Aedes aegypti is a human-biting mosquito and the primary vector of human dengue and yellow fever viruses. It is also considered the principal vector of Chikungunya virus in Asia. It is believed that this mosquito originally migrated from West Africa to the North and South America in the 15th century aboard slave ships, after which yellow fever appeared in the New World. Details on the characteristics of this insect are also highlighted.

Parasitic mites associated with spiders are spreading world-wide through the trade in tarantulas and other pet species. Ljunghia pulleinei Womersley, a mesostigmatic laelapid mite originally found in association with the mygalomorph spider Selenocosmia stirlingi Hogg (Theraphosidae) in Australia, is redescribed and illustrated on the basis of specimens from the African theraphosid spider Pterinochilus chordatus (Gerstä cker) kept in captivity in the British Isles (Wales). The mite is known from older original descriptions of Womersley in 1956; the subsequent redescription of Domrow in 1975 seems to be questionable in conspecificity of treated specimens with the type material. Some inconsistencies in both descriptions are recognised here as intraspecific variability of the studied specimens. The genus Arachnyssus Ma, with species A. guangxiensis (type) and A. huwenae, is not considered to be a valid genus, and is included in synonymy with Ljunghia Oudemans. A new key to world species of the genus Ljunghia is provided. [ABSTRACT FROM AUTHOR]

Internal bacterial communities of synanthropic mites Acarus siro, Dermatophagoides farinae, Lepidoglyphus destructor, and Tyrophagus putrescentiae (Acari: Astigmata) were analyzed by culturing and culture-independent approaches from specimens obtained from laboratory colonies. Homogenates of surface-sterilized mites were used for cultivation on non-selective agar and DNA extraction. Isolated bacteria were identified by sequencing of the 16S rRNA gene. PCR amplified 16S rRNA genes were analyzed by terminal restriction fragment length polymorphism analysis (T-RFLP) and cloning sequencing. Fluorescence in situ hybridization using universal bacterial probes was used for direct bacterial localization. T-RFLP analysis of 16S rRNA gene revealed distinct species-specific bacterial communities. The results were further confirmed by cloning and sequencing (284 clones). L. destructor and D. farinae showed more diverse communities then A. siro and T. putrescentiae. In the cultivated part of the community, the mean CFUs from four mite species ranged from 5.2 × 10 to 1.4 × 10 per mite. D. farinae had significantly higher CFUs than the other species. Bacteria were located in the digestive and reproductive tract, parenchymatical tissue, and in bacteriocytes. Among the clones, Bartonella-like bacteria occurring in A. siro and T. putresecentiae represented a distinct group related to Bartonellaceae and to Bartonella-like symbionts of ants. The clones of high similarity to Xenorhabdus cabanillasii were found in L. destructor and D. farinae, and one clone related to Photorhabdus temperata in A. siro. Members of Sphingobacteriales cloned from D. farinae and A. siro clustered with the sequences of ' Candidatus Cardinium hertigii' and as a separate novel cluster. [ABSTRACT FROM AUTHOR]

Background: Primary bacterial endosymbionts of insects (p-endosymbionts) are thought to be undergoing the process of Muller's ratchet where they accrue slightly deleterious mutations due to genetic drift in small populations with negligible recombination rates. If this process were to go unchecked over time, theory predicts mutational meltdown and eventual extinction. Although genome degradation is common among p-endosymbionts, we do not observe widespread pendosymbiont extinction, suggesting that Muller's ratchet may be slowed or even stopped over time. For example, selection may act to slow the effects of Muller's ratchet by removing slightly deleterious mutations before they go to fixation thereby causing a decrease in nucleotide substitutions rates in older p-endosymbiont lineages. Methodology/Principal Findings: To determine whether selection is slowing the effects of Muller's ratchet, we determined the age of the Candidatus Riesia/sucking louse assemblage and analyzed the nucleotide substitution rates of several pendosymbiont lineages that differ in the length of time that they have been associated with their insect hosts. We find that Riesia is the youngest p-endosymbiont known to date, and has been associated with its louse hosts for only 13-25 My. Further, it is the fastest evolving p-endosymbiont with substitution rates of 19-34% per 50 My. When comparing Riesia to other insect p-endosymbionts, we find that nucleotide substitution rates decrease dramatically as the age of endosymbiosis increases. Conclusions/Significance: A decrease in nucleotide substitution rates over time suggests that selection may be limiting the effects of Muller's ratchet by removing individuals with the highest mutational loads and decreasing the rate at which new mutations become fixed. This countering effect of selection could slow the overall rate of endosymbiont extinction. [ABSTRACT FROM AUTHOR]

The primary endosymbiotic bacteria from three species of parasitic primate lice were characterized molecularly. We have confirmed the characterization of the primary endosymbiont (P-endosymbiont) of the human head/body louse Pediculus humanus and provide new characterizations of the P-endosymbionts from Pediculus schaeffi from chimpanzees and Pthirus pubis, the pubic louse of humans. The endosymbionts show an average percent sequence divergence of 11 to 15% from the most closely related known bacterium ‘Candidatus Arsenophonus insecticola.’ We propose that two additional species be added to the genus ‘Candidatus Riesia.’ The new species proposed within ‘Candidatus Riesia’ have sequence divergences of 3.4% and 10 to 12% based on uncorrected pairwise differences. Our Bayesian analysis shows that the branching pattern for the primary endosymbionts was the same as that for their louse hosts, suggesting a long coevolutionary history between primate lice and their primary endosymbionts. We used a calibration of 5.6 million years to date the divergence between endosymbionts from human and chimpanzee lice and estimated an evolutionary rate of nucleotide substitution of 0.67% per million years, which is 15 to 30 times faster than previous estimates calculated for Buchnera, the primary endosymbiont in aphids. Given the evidence for cospeciation with primate lice and the evidence for fast evolutionary rates, this lineage of endosymbiotic bacteria can be evaluated as a fast-evolving marker of both louse and primate evolutionary histories. [ABSTRACT FROM AUTHOR]

In an attempt to evaluate the susceptibility of the mosquito Culex quinquefasciatus to bacterial agents, a population naturally infected with a Wolbachia pipientis wPipSJ native strain was tested against the action of three bacterial mosquitocides, Bacillus thuringiensis subsp. israelensis, Bacillus wiedmannii biovar thuringiensis and Lysinibacillus sphaericus. Tests were carried out on mosquito larvae with and without Wolbachia (controls). Cx. quinquefasciatus naturally infected with the native wPipSJ strain proved to be more resistant to the pathogenic action of the three mosquitocidal bacterial strains. Additionally, wPipSJ was fully characterised using metagenome-assembled genomics, PCR–RFLP (PCR-Restriction Fragment Length Polymorphism) and MLST (MultiLocus Sequence Typing) analyses. This Wolbachia strain wPipSJ belongs to haplotype I, group wPip-III and supergroup B, clustering with other mosquito wPip strains, such as wPip PEL, wPip JHB, wPip Mol, and wAlbB; showing the southernmost distribution in America. The cytoplasmic incompatibility phenotype of this strain was revealed via crosses between wildtype (Wolbachia+) and antibiotic treated mosquito populations. The results of the tests with the bacterial agents suggest that Cx. quinquefasciatus naturally infected with wPipSJ is less susceptible to the pathogenic action of mosquitocidal bacterial strains when compared with the antibiotic-treated mosquito isoline, and is more susceptible to B. thuringiensis subsp. israelensis than to the other two mosquitocidal agents. [ABSTRACT FROM AUTHOR]

This report interprets the presence of mite species in three clandestine graves in Europe, evaluating their potential use as trace evidence or markers. Grave 1 (Sweden): Two mite species Rhizoglyphus robini Claparède, 1869 and Parasitus loricatus (Wankel, 1861) were recovered from the surface of a body buried in a shallow grave in an area surrounded by trees, in close vicinity to house gardens. Grave 2 (Germany): Phoretic deutonymphs of Gamasodes spiniger (Trägårdh, 1910) were attached to an adult fly (Diptera: Sphaeroceridae) found within a shallow grave containing two human bodies covered in soil and dung. Grave 3 (France): P. loricatus were recovered from the soil around a body buried in a deep grave (80 cm under). In graves 1 and 3 both corpses were undergoing advanced decay and skeletization, the locations match with the subterranean habit of P. loricatus, highlighting the value of this species as a marker of graves or burials in soil and during late decomposition. R. robini is a soil mite that feeds on decayed roots and bulbs; this mite species confirms the location of the corpse within top soil, agreeing with a more specific type of superficial burial, a shallow grave. In case 2, the presence of both coprophiles, the mite G. spiniger and the carrier fly confirm association of remains with dung or animal feces. The three mite species are reported for the first time in human graves. There are no previous records of R. robini from Sweden. [ABSTRACT FROM AUTHOR]

Spray-drying of lactic cultures provides direct-to-vat starters, which facilitate their commercialization and use. However, this process may alter the metabolic activity and deteriorate technological features. In this work, we assessed the influence of spray-drying on the survival and aroma production of two strains of mesophilic lactobacilli: Lactobacillus paracasei 90 and Lactobacillus plantarum 91, which have already been characterized as good adjunct cultures. The spray-drying was carried out using a laboratory scale spray and the dried cultures were monitored during the storage for the survival rate. The dried cultures were applied to two cheese models: sterile cheese extract and miniature soft cheese. The influence on the carbohydrate metabolism and the production of organic acids and volatile compounds was determined. Both strains retained high levels of viable counts in the powder after drying and during the storage at 5 °C for twelve months. In addition, they also remained at high level in both cheese models during incubation or ripening. Similar profiles of carbohydrate fermentation and bioformation of volatile compounds were observed in the cheese extracts for each of the strains when tested as both fresh and dried cultures. In addition, the ability of Lb. paracasei 90 to increase the production of acetoin and diacetyl remarkably in cheese models was also confirmed for the spray-dried culture. [ABSTRACT FROM AUTHOR]

The influence of the use of cheese milk enriched with skim milk powder (SMP) and the addition of two adjunct cultures (Lacticaseibacillus paracasei 90 or Lacticaseibacillus rhamnosus 73) on the levels of organic acids, carbohydrates and volatile compounds and on the sensory characteristics of Cremoso cheeses was studied. The addition of SMP increased the levels of compounds present in the milk or derived from them: citric acid, lactose, and galactose, and most of the volatile compounds. The addition of adjunct cultures increased some compounds with preservative and aromatic properties. Acceptability scores decreased slightly due to the addition of SMP, while it increased due to the incorporation of the strain 73. However, all cheeses had high acceptability, which was associated to the terms tasty, for the entire family, and healthy. Both strategies allowed good-quality cheeses to be obtained, showing some chemical changes compared with traditional cheese. [ABSTRACT FROM AUTHOR]

The importance of the thermal environment for ectotherms and its relationship with thermal physiology and ecology is widely recognized. Several models have been proposed to explain the evolution of the thermal biology of ectotherms, but experimental studies have provided mixed support. Lizards from the Liolaemus goetschi group can be found along a wide latitudinal range across Argentina. The group is monophyletic and widely distributed, and therefore provides excellent opportunities to study the evolution of thermal biology. We studied thermal variables of 13 species of the L. goetschi group, in order to answer three questions. First, are aspects of the thermal biology of the L. goetschi group modelled by the environment or are they evolutionarily conservative? Second, have thermal characteristics of these animals co-evolved? And third, how do the patterns of co-evolution observed within the L. goetschi group compare to those in a taxonomically wider selection of species of Liolaemus? We collected data on 13 focal species and used species information of Liolaemus lizards available in the literature and additional data obtained by the authors. We tackled these questions using both conventional and phylogenetically based analyses. Our results show that lizards from the L. goetschi group and the genus Liolaemus in general vary in critical thermal minimum in relation to mean air temperature, and particularly the L. goetschi group shows that air temperature is associated with critical thermal range, as well as with body temperature. Although the effect of phylogeny cannot be ignored, our results indicate that these thermal biology aspects are modelled by cold environments of Patagonia, while other aspects (preferred body temperature and critical thermal maximum) are more conservative. We found evidence of co-evolutionary patterns between critical thermal minimum and preferred body temperature at both phylogenetic scales (the L. goetschi group and the extended sample of 68 Liolaemus species). [ABSTRACT FROM AUTHOR]

We designed fluorescence in situ hybridization probes for two distinct microsporidian clades and demonstrated their application in detecting, respectively, Nosemal Vairimorpha and Dictyoceola species. We used them to study the vertical transmission of two microsporidia infecting the amphipod Gammarus duebeni. [ABSTRACT FROM AUTHOR]

As an obligatory parasite of humans, the body louse (Pediculus humanus humanus) is an important vector for human diseases, including epidemic typhus, relapsing fever, and trench fever. Here, we present genome sequences of the body louse and its primary bacterial endosymbiont Candidatus Riesia pediculicola. The body louse has the smallest known insect genome, spanning 108 Mb. Despite its status as an obligate parasite, it retains a remarkably complete basal insect repertoire of 10,773 protein-coding genes and 57 microRNAs. Representing hemimetabolous insects, the genome of the body louse thus provides a reference for studies of holometabolous insects. Compared with other insect genomes, the body louse genome contains significantly fewer genes associated with environmental sensing and response, including odorant and gustatory receptors and detoxifying enzymes. The unique architecture of the 18 minicircular mitochondrial chromosomes of the body louse may be linked to the loss of the gene encoding the mitochondrial single-stranded DNA binding protein. The genome of the obligatory louse endosymbiont Candidatus Riesia pediculicola encodes less than 600 genes on a short, linear chromosome and a circular plasmid. The plasmid harbors a unique arrangement of genes required for the synthesis of pantothenate, an essential vitamin deficient in the louse diet. The human body louse, its primary endosymbiont, and the bacterial pathogens that it vectors all possess genomes reduced in size compared with their free-living close relatives. Thus, the body louse genome project offers unique information and tools to use in advancing understanding of coevolution among vectors, symbionts, and pathogens. [ABSTRACT FROM AUTHOR]

Previous studies from our laboratory have demonstrated the presence of two integral proteins with glycosidase activity in the plasma membrane of Drosophila melanogaster spermatozoa and we have suggested that these enzymes might have a role in sperm–egg binding. In this study the glycosidases have been purified and characterized. We have evidenced the presence of three distinct enzymes, two β-N-acetylhexosaminidase isoforms, named HEX 1 and HEX 2, and an α-mannosidase. The molecular size of the native enzymes estimated by gel filtration was 158 kDa for β-hexosaminidases and 317 kDa for α-mannosidase. SDS-PAGE showed that HEX 1 and HEX 2 are dimers formed by subunits with different molecular sizes, whereas α-mannosidase consists of three subunits with different molecular weights. All the enzymes are terminally glycosylated. Characterization of the purified enzymes included their 4-methylumbelliferyl-substrate preferences, kinetic properties, inhibitor constants and thermal stability. On the basis of substrate specificity, kinetics and the results of inhibition studies, β-hexosaminidases appear to differ from each other. HEX 1and HEX 2 are similar to mammalian isoenzyme A and isoenzyme B, respectively.These findings represent the first report on the characterization of sperm proteins that are potentially involved in interactions with the egg in Insects. [Copyright &y& Elsevier]

In this work, we simulated cold chain interruptions in soft cheeses of high-moisture to assess their impact on ripening, putting attention on the behaviour of an adjunct culture of Lactobacillus paracasei 90 (L90) when it was added. Temperature variation did not change starter culture levels but it significantly increased L90 population at 60 days in cheeses with cold chain interruption. Cold chain interruptions and adjunct culture led to an increase of the proteolysis levels and produced changes in the carbohydrate fermentation, volatile compounds profiles and sensory scores. In cheeses with cold chain interruptions, L90 did not cause any defects and maintained its capacity of improving flavour and odour intensities by increasing the levels of diacetyl and acetoin, and decreasing pungent taste and compounds associated with rancidity. In addition, samples with adjunct culture presented increased levels of lactic acid without being perceived as a defect by the sensory panel. [ABSTRACT FROM AUTHOR]

Although Mar del Plata is the most important city on the Atlantic coast of Argentina, mosquitoes inhabiting such area are almost uncharacterized. To increase our knowledge in their distribution, we sampled specimens of natural populations. After the morphological identification based on taxonomic keys, sequences of DNA from small ribosomal subunit (18S rDNA) and cytochrome c oxidase I (COI) genes were obtained from native species and the phylogenetic analysis of these sequences were done. Fourteen species from the genera Uranotaenia, Culex, Ochlerotatus and Psorophora were found and identified. Our 18S rDNA and COI-based analysis indicates the relationships among groups at the supra-species level in concordance with mosquito taxonomy. The introduction and spread of vectors and diseases carried by them are not known in Mar del Plata, but some of the species found in this study were reported as pathogen vectors. [ABSTRACT FROM AUTHOR]