Host-parasite checklists are essential resources in ecological parasitology, and are regularly used as sources of data in comparative studies of parasite species richness across host species, or of ...host specificity among parasite species. However, checklists are only useful datasets if they are relatively complete, that is, close to capturing all host–parasite associations occurring in a particular region. Here, we use three approaches to assess the completeness of 25 checklists of metazoan parasites in vertebrate hosts from various geographic regions. First, treating checklists as interaction networks between a set of parasite species and a set of host species, we identify networks with a greater connectance (proportion of realized host–parasite associations) than expected for their size. Second, assuming that the cumulative rise over time in the number of known host–parasite associations in a region tends toward an asymptote as their discovery progresses, we attempt to extrapolate the estimated total number of existing associations. Third, we test for a positive correlation between the number of published reports mentioning an association and the time since its first record, which is expected because observing and reporting host–parasite associations are frequency-dependent processes. Overall, no checklist fared well in all three tests, and only three of 25 passed two of the tests. These results suggest that most checklists, despite being useful syntheses of regional host–parasite associations, cannot be used as reliable sources of data for comparative analyses.
Translocations for conservation often involve species limited to relict distributions. However, uncertainty can exist regarding the ability of source individuals to acclimatise following a shift to a ...distant location. We investigated the ability of captive-reared juvenile tuatara (Sphenodon punctatus) of Cook Strait stock (41°S) to adjust to outdoor, predator-protected pens within Orokonui Ecosanctuary (45 °S). We examined potential basking and within burrow temperatures, the influence of temperature on emergence, and growth rates in comparison with other locations. Tuatara at Orokonui reached their preferred temperature when basking over summer, and burrows provided protection from freezing over winter. Emergence was temperature-dependent and essentially ceased during winter. Growth rates of Orokonui-held juveniles were within the range for four other captive-rearing facilities and faster than for wild juveniles from a Cook Strait population. As all Orokonui-held juveniles have survived and grown we conclude that the climate at this southern location is suitable to consider a free-release.
ABSTRACT
Maternal nutrition can have long‐term effects on offspring morphology, physiology and behaviours. However, it is unclear whether mothers ‘program’ offspring behavioural coping strategy ...(proactive/reactive) according to the predicted nutritional quality of their future environment. We conducted a systematic review on this topic and meta‐analytically synthesized relevant experimental data on mice and rats (46 studies). We included data from experiments where dams were subjected to caloric restriction, protein restriction or overfeeding around gestation and subsequently measured offspring activity, exploration, or anxiety. Overall, little evidence existed for effects of maternal nutrition on the three investigated behavioural traits. The high heterogeneity observed in the data set suggests that maternal programming may sometimes occur. However, because offspring had access to a balanced diet before testing, behaviours may have been reprogrammed. Our results may indicate that reprogrammed behaviours could ameliorate negative effects associated with sub‐optimal nutrition in early life. Further, our systematic review revealed clear knowledge gaps and fruitful future research avenues.
The level of phosphorylation within cells is tightly regulated by the concerted action of protein kinases and protein phosphatases Hunter, T. (1995) Cell80, 225–236. Disregulation in the activity of ...either of these players can lead to cellular transformation. Many protein tyrosine kinases are proto‐oncogenes and it has been postulated that some protein phosphatases may act as tumor suppressors. Herein we will review the recent findings addressing the roles the candidate tumor suppressor PTEN/MMAC1/TEP1 (PTEN, phosphatase and tensin homologue deleted from chromosome 10; MMAC 1, mutated in multiple advanced cancers 1; TEP1, TGF β regulated and epithelial cell enriched phosphatase 1) plays in signal transduction and tumorigenesis. PTEN is a dual specificity protein phosphatase (towards phospho‐Ser/Thr and phospho‐Tyr) and, unexpectedly, also has a phosphoinositide 3‐phosphatase activity. PTEN plays an important role in the modulation of the 1‐phosphatidylinositol 3‐kinase (PtdIns 3‐kinase) pathway, by catalyzing the degradation of the PtdIns(3,4,5)P3 generated by PtdIns 3‐kinase; this inhibits the downstream functions mediated by the PtdIns 3‐kinase pathway, such as activation of protein kinase B (PKB, also known as Akt), cell survival and cell proliferation. Furthermore, PTEN modulates cell migration and invasion by negatively regulating the signals generated at the focal adhesions, through the direct dephosphorylation and inhibition of focal adhesion kinase (FAK). Growth factor receptor signaling is also negatively regulated by PTEN, through the inhibition of the adaptor protein Shc. While some of the functions of PTEN have been elucidated, it is clear that there is much more to discover about the roles of this unique protein.
We report on the performance of the MIMOSA8 (HiMAPS1) chip. The chip is a 128times32 pixels array where 24 columns have discriminated binary outputs and eight columns analog test outputs. Offset ...correction techniques are used extensively in this chip to overcome process related mismatches. The array is divided in four blocks of pixels with different conversion factors and is controlled by a serially programmable sequencer. MIMOSA8 is a representative of the CMOS sensors development option considered as a promising candidate for the Vertex Detector of the future International Linear Collider (ILC). The readout technique, implemented on the chip, combines high spatial resolution capabilities with high processing readout speed. Data acquisition, providing control of the chip and signal buffering and linked to a VME system, was made on the eight analog outputs. Analog data, without and with a 55 Fe X-ray source, were acquired and processed using off-line analysis software. From the reconstruction of pixel clusters, built around a central pixel, we deduce that the charge spread is limited to the closest 25 pixels and almost all the available charge is collected. The position of the total charge collection peak (and subsequently the charge-to-voltage conversion factor) stays unaffected when the clock frequency is increased even up to 150 MHz (13.6 mus readout time per frame). The discriminators, placed in the readout chain, have proved to be fully functional. Beam tests have been made with high energy electrons at DESY (Germany) to study detection efficiency. The results prove that MIMOSA8 is the first and fastest successful monolithic active pixel sensor with on-chip signal discrimination for detection of MIPs
CMOS monolithic active pixel sensors (MAPS) are proposed as a technology for various vertex detectors in nuclear and particle physics. We discuss the mechanisms of ionizing radiation damage on MAPS ...hosting the dead time free, so-called self bias pixel. Moreover, we introduce radiation hardened sensor designs which allow operating detectors after exposing them to irradiation doses above 1
Mrad.
Recently, CMOS Monolithic Active Pixels Sensors (MAPS) have become strong candidates for pixel detectors used in high energy physics experiments. A very good spatial resolution lower than 5 mum can ...be obtained with these detectors. A recent fast MAPS chip, designed in AMS CMOS 0.35 mum Opto process and called MIMOSA16 (HiMAPS2), was submitted to foundry in June 2006. The chip is a 128times32 pixels array where 8 columns have analog test outputs and 24 columns have their outputs connected to offset compensated discriminator stages. The pixel array is addressed row-wise. The array is divided in four blocks of pixels with different charge-to-voltage conversion factors and is controlled by a serially programmable sequencer. The sequencer operates as a pattern generator which delivers control signals both to the pixels and to the column-level discriminators. Discriminators have a common adjustable threshold. This chip is the basis of the final sensor of the EUDET-JRA1 beam telescope which will be installed at DESY in 2009. In this paper, laboratory tests results using a 55 Fe source together with beam tests results obtained at CERN using Minimum Ionizing Particles (MIPs) are presented.
The Run II of the D$\emptyset$ experiment was started in March 2001. The first preliminary results on searches for new physics are presented, with a luminosity of $\sim$10 pb$^{-1}$ __ from the data ...collected in 2001–2002. We report results in mSUGRA (jets + missing $E_{\rm T}$ _ channel), GMSB (diphotons), RPV (trileptons and like sign dileptons) and large extra dimensions (dielectrons and diphotons).
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