581 research outputs found
Anthropogenic nitrogen autotrophy and heterotrophy of the world's watersheds: Past, present, and future trends
Anthropogenic nitrogen autotrophy of a territory is defined as the nitrogen flux associated with local production of harvested crops and grass consumed by livestock grazing (in kg N/km(2)/yr). Nitrogen heterotrophy is the nitrogen flux associated with local food and feed consumption by humans and domestic animals. These two summarizing characteristics (anthropogenic nitrogen autotrophy and heterotrophy (ANAH)) indicate the degree of anthropogenic perturbation of the nitrogen cycle by agriculture and human consumption: their balance value provides information on either the potential for commercial export or the need to import agricultural goods; in a watershed, their vector sum is related to the nitrogen flux delivered to the sea. These indicators were calculated for all the watersheds in the Global Nutrient Export from Watersheds (NEWS) database for 1970 and 2000, as well as for 2030 and 2050, according to Millennium Ecosystem Assessment scenarios. During this 30 year period, many watersheds shifted from relatively balanced situations toward either more autotrophic or more heterotrophic conditions. This trend is predicted to become more pronounced over the next 50 year
Emotional, cognitive and behavioral self-regulation in forensic psychiatric patients:Changes over time and associations with childhood trauma, identity and personality pathology
The construct of self-regulation is of particular interest to the forensic psychiatric practice due to its associations with both clinical and criminal outcomes, as well as recidivism. However, research on different components of self-regulation within forensic psychiatric practice is rare. The current study aimed to gain knowledge on the construct of self-regulation in a sample of forensic psychiatric patients (N = 94). Firstly, by investigating change of emotional, behavioral and cognitive self-regulation over the course of 12 months in state-mandated care in a treatment facility. Secondly, by looking at the associations between these three elements of self-regulation and childhood trauma, identity dysfunction and personality pathology. Repeated measures ANOVA showed little to no difference in average self-regulation over time (only for behavioral regulation), and rank-order stability was relatively high in most cases. Path analysis showed that: emotion regulation was associated with all outcomes; behavioral regulation with all except childhood trauma and detachment; and cognitive regulation only with antagonism and negative affectivity. Findings suggest short-term changes are unlikely and indicate relative importance of emotional, and to some extent behavioral regulation for clinical practice. However, due to sample size restrictions, interpretations should be made with caution
Differences in Climbing Ability of Cimex lectularius and Cimex hemipterus (Hemiptera: Cimicidae)
The climbing abilities of two bed bug species, Cimex lectularius L. and Cimex hemipterus (F.), were determined
by evaluating their escape rates from smooth surface pitfall traps using four commercial bed bug monitors
(Verifi Bed Bug Detector, ClimbUp Insect Interceptor, BlackOut Bed Bug Detector, and SenSci Volcano Bed Bug
Detector). All detectors were used in the absence of lures or attractants. Unlike C. lectularius, adult C. hemipterus
were able to escape from all traps. On the other hand, no or a low number nymphs of both species escaped,
depending on the evaluated traps. Examination of the vertical friction force of adults of both species revealed a
higher vertical friction force in C. hemipterus than in C. lectularius. Scanning electron microscope micrograph
observation on the tibial pad of adult bed bugs of C. hemipterus showed the presence of a greater number of
tenent hairs on the tibial pad than on that of adult C. lectularius. No tibial pad was found on the fourth and fifth
instars of both species. Near the base of the hollow tenent hairs is a glandular epithelium that is better
developed in adult C. hemipterus than in adult C. lectularius. This study highlights significant morphological differences
between C. lectularius and C. hemipterus, which may have implications in the monitoring and management
of bed bug infestations
Worker policing in the German wasp Vespula germanica
In some ants, bees, and wasps, workers kill or "police” male eggs laid by other workers in order to maintain the reproductive primacy of the queen. Kin selection theory predicts that multiple mating by the queen is one factor that can selectively favor worker policing. This is because when the queen is mated to multiple males, workers are more closely related to the queen's sons than to the sons of other workers. Earlier work has suggested that reproductive patterns in the German wasp Vespula germanica may contradict this theory, because in some colonies a large fraction of the adult males were inferred to be the workers' sons, despite the effective queen mating frequency being greater than 2 (2.4). In the present study, we reexamine the V. germanica case and show that it does support the theory. First, genetic analysis confirms that the effective queen mating frequency is high, 2.9, resulting in workers being more related to the queen's sons than to other workers' sons. Second, behavioral assays show that worker-laid eggs are effectively killed by other workers, despite worker-laid eggs having the same intrinsic viability as queen-laid ones. Finally, we estimate that approximately 58.4% of the male eggs but only 0.44% of the adult males are worker derived in queenright colonies, consistent with worker reproduction being effectively police
Bcl-XL Inhibits Membrane Permeabilization by Competing with Bax
Although Bcl-XL and Bax are structurally similar, activated Bax forms large oligomers that permeabilize the outer mitochondrial membrane, thereby committing cells to apoptosis, whereas Bcl-XL inhibits this process. Two different models of Bcl-XL function have been proposed. In one, Bcl-XL binds to an activator, thereby preventing Bax activation. In the other, Bcl-XL binds directly to activated Bax. It has been difficult to sort out which interaction is important in cells, as all three proteins are present simultaneously. We examined the mechanism of Bax activation by tBid and its inhibition by Bcl-XL using full-length recombinant proteins and measuring permeabilization of liposomes and mitochondria in vitro. Our results demonstrate that Bcl-XL and Bax are functionally similar. Neither protein bound to membranes alone. However, the addition of tBid recruited molar excesses of either protein to membranes, indicating that tBid activates both pro- and antiapoptotic members of the Bcl-2 family. Bcl-XL competes with Bax for the activation of soluble, monomeric Bax through interaction with membranes, tBid, or t-Bid-activated Bax, thereby inhibiting Bax binding to membranes, oligomerization, and membrane permeabilization. Experiments in which individual interactions were abolished by mutagenesis indicate that both Bcl-XL–tBid and Bcl-XL–Bax binding contribute to the antiapoptotic function of Bcl-XL. By out-competing Bax for the interactions leading to membrane permeabilization, Bcl-XL ties up both tBid and Bax in nonproductive interactions and inhibits Bax binding to membranes. We propose that because Bcl-XL does not oligomerize it functions like a dominant-negative Bax in the membrane permeabilization process
Behavioral mechanisms and morphological symptoms of zombie ants dying from fungal infection
<p>Abstract</p> <p>Background</p> <p>Parasites that manipulate host behavior can provide prominent examples of extended phenotypes: parasite genomes controlling host behavior. Here we focus on one of the most dramatic examples of behavioral manipulation, the death grip of ants infected by <it>Ophiocordyceps </it>fungi. We studied the interaction between <it>O. unilateralis s.l</it>. and its host ant <it>Camponotus leonardi </it>in a Thai rainforest, where infected ants descend from their canopy nests down to understory vegetation to bite into abaxial leaf veins before dying. Host mortality is concentrated in patches (graveyards) where ants die on sapling leaves <it>ca</it>. 25 cm above the soil surface where conditions for parasite development are optimal. Here we address whether the sequence of ant behaviors leading to the final death grip can also be interpreted as parasite adaptations and describe some of the morphological changes inside the heads of infected workers that mediate the expression of the death grip phenotype.</p> <p>Results</p> <p>We found that infected ants behave as zombies and display predictable stereotypical behaviors of random rather than directional walking, and of repeated convulsions that make them fall down and thus precludes returning to the canopy. Transitions from erratic wandering to death grips on a leaf vein were abrupt and synchronized around solar noon. We show that the mandibles of ants penetrate deeply into vein tissue and that this is accompanied by extensive atrophy of the mandibular muscles. This lock-jaw means the ant will remain attached to the leaf after death. We further present histological data to show that a high density of single celled stages of the parasite within the head capsule of dying ants are likely to be responsible for this muscular atrophy.</p> <p>Conclusions</p> <p>Extended phenotypes in ants induced by fungal infections are a complex example of behavioral manipulation requiring coordinated changes of host behavior and morphology. Future work should address the genetic basis of such extended phenotypes.</p
Eignung der Gammaspektrometrie zum Kartieren der Mächtigkeit und der C-Vorräte von Moorböden
Moore stellen einen der großen variablen Bodenspeicher für organisches C dar. Es wird geprüft werden, ob die Gammaspektrometrie zum Kartieren von Moorböden in Südwestdeutschland anwendbar ist. Im Ergebnis lassen sich grundsätzlich mit der Gammaspektrometrie Torfmächtigkeiten bis zu einem Meter in Abhängigkeit der Strahlungseigenschaften des unterliegenden Substrates differenzieren. Allerdings ist in Landschaftsräumen mit unterschiedlicher Geologie auch eine getrennte Kalibrierung dieses Verfahrens erforderlich sind
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Beam dynamics design of the 211 MeV APT normal conducting linac
This paper describes the normal conducting linac design that is part of the Accelerator for Production of Tritium (APT) project. The new version of PARMILA designed this linac. This linac accepts the beam from the 6.7 MeV radio frequency quadrupole without a separate matching section. At about 10 MeV, it has a smooth transition in the length of period from 8{beta}{lambda} to 9{beta}{lambda} in quadrupole focusing lattice. This adjustment of the period was needed to provide sufficient space for the quadrupole focusing magnets and beam diagnostic equipment. The linac consists of the coupled cavity drift tube linac up to 97 MeV and coupled cavity linac above 97 MeV
Reconstruire la ville sur la ville - Recyclage des espaces dégradés. Etat d'avancement
audience: researcher, professional, studentRapport intermédiaire de la subvention 2004-200
Detection of Aspergillus-specific antibodies by agar gel double immunodiffusion and IgG ELISA in feline upper respiratory tract aspergillosis.
Highlights: Feline antibodies against cryptic Aspergillus spp. cross react with an aspergillin containing A. fumigatus antigens. • Brachycephalic cats are prone to upper respiratory tract aspergillosis (URTA). • The agar gel immunodiffusion (AGID) assay has low sensitivity for diagnosis of URTA. • IgG ELISA has high sensitivity and specificity for diagnosis of URTA. • This study provides evidence that cats with URTA are systemically immunocompetent. Abstract Feline upper respiratory tract aspergillosis (URTA) is an emerging infectious disease. The aims of this study were: (1) to assess the diagnostic value of detection of Aspergillus-specific antibodies using an agar gel double immunodiffusion (AGID) assay and an indirect immunoglobulin G (IgG) ELISA; and (2) to determine if an aspergillin derived from mycelia of Aspergillus fumigatus, Aspergillus niger and Aspergillus flavus can be used to detect serum antibodies against cryptic Aspergillus spp. in Aspergillus section Fumigati. Sera from cats with URTA (group 1: n = 21) and two control groups (group 2: cats with other upper respiratory tract diseases, n = 25; group 3: healthy cats and cats with non-respiratory, non-fungal illness, n = 84) were tested. Isolates from cats with URTA comprised A. fumigatus (n = 5), A. flavus (n = 1) and four cryptic species: Aspergillus felis (n = 12), Aspergillus thermomutatus (Neosartorya pseudofischeri, n = 1), Aspergillus lentulus (n = 1) and Aspergillus udagawae (n = 1). Brachycephalic purebred cats were significantly more likely to develop URTA than other breeds (P = 0.013). The sensitivity (Se) of the AGID was 43% and the specificity (Sp) was 100%. At a cut-off value of 6 ELISA units/mL, the Se of the IgG ELISA was 95.2% and the Sp was 92% and 92.9% for groups 2 and 3 cats, respectively. Aspergillus-specific antibodies against all four cryptic species were detected in one or both assays. Assay Se was not associated with species identity. Detection of Aspergillus-specific antibodies by IgG ELISA has high Se and Sp for diagnosis of feline URTA. Keywords: Aspergillosis; Aspergillus spp; Sino-nasal; Sino-orbital; Felinefunded by an Australian Companion Animal Health Foundation grant (015/201
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