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Detecting changes in whelk abundance using hermit crab shell utilization in Oregon's rocky marine intertidal
Utilization and preference of whelk shells by the hairy hermit crab are examined in the following to further define the ecology of Oregon’s mid to low intertidal ecosystems. The study was conducted at Tokatee Kloochman State Natural Area (TK) where I made observations before collecting data. My observations were of two whelk species, the channeled dogwinkle (Nucella canaliculata), and the northern striped dogwinkle (Nucella ostrina). Observing an apparent decreased abundance of the channeled dogwinkle and an unchanging abundance of the northern striped dogwinkle initiated the preliminary research of this study. Cause for such a shift in species abundance is a topic of interest, however we must first establish that this shift has indeed occurred and discover how it may be influencing the current ecosystem at TK. The goal of this study is to determine if channeled dogwinkle survival had changed in the early spring of 2016 at the TK site.
Searching for empty shells of the two species, as evidence that many individuals from one species have died in recent months, was largely unsuccessful. There were not enough empty shells at TK to determine if channeled shells are more abundant than striped. Investigating why there would be so few empty whelk shells I found a potential explanation. Hermit crabs use vacant snail shells and there are many hermit crabs at the TK site. I shifted my focus and proposed that if there was a decrease in channeled dogwinkle abundance it may be observed in the shell utilization by hermit crabs. The hairy hermit crab (Pagurus hirsutiusculus) uses empty snail and whelk shells, but has expressed a preference for shells of certain species in similar ecosystems. I have observed these hermit crabs at TK using shells from both species so I needed to determine whether a shell preference could account for differential utilization of shells by the hermit crabs. I also needed to assess whelk abundances for the same reason. If the hermit crab does not have a shell preference between the channeled and the striped species then a higher utilization of shells from one whelk species would be evidence for greater numbers of vacant shells from this species available to the hermit crabs. The shell preference experiments did not show a significant shell preference between the two species of whelk. Also, I found no statistical evidence that the channeled species and the striped species are at different abundances. Finally, I could confidently use the shell utilization of hairy hermit crab at TK to determine whether more channeled dogwinkle shells were recently available than northern striped dogwinkle. The shell utilization study did reveal a statistically higher number of channeled dogwinkle shells being used by the hairy hermit crab than the northern striped dogwinkle
Unlocking private investment in soil carbon in England
New recommendations for the design of high-integrity agricultural soil carbon markets highlight difficulties for farmers to enrol in both Sustainable Farming Incentive (SFI) and emerging agricultural soil carbon markets. To unlock private finance, new public schemes should focus on paying farmers for soil carbon testing, and keeping carbon stored in already well-managed, carbon-rich soils
Association between frontal sinus development and persistent metopic suture
Background: Frontal sinuses are 2 irregular cavities, placed between 2 lamina of frontal bone. Expansion continues during childhood and reaches full size after puberty. Persistent metopic suture is one of the factors that are related to abnormal frontal sinus development. In this study, we want to discuss about the coexistence of persistent metopic suture and abnormal frontal sinus development using radiological techniques.Materials and methods: In this retrospectively planned study, images of 631 patients were examined, 217 (34.4%) of them were men and 414 (65.6%) of them were women. Brain computed tomography and magnetic resonance images were retrieved from the electronic archive for analysis.Results: In this study, frontal sinus development is categorised as right side atrophy, left side atrophy, bilateral atrophy and bilaterally developed sinuses. The presence of metopic suture was accepted as persistent metopic suture. Frontal sinus atrophy was found in 22.7% and persistent metopic sutures were found in 9.7% of overall.Conclusions: In this study, no significant results were detected that were relatedto the frontal sinus agenesis or dismorphism associated with persistent metopicsuture. We conclude that, although publications propounding metopism thatleads to abnormal frontal sinus development are present in the literature, noreasonable explanation has been mentioned in these articles; and we believe thatthese findings are all incidental.
Community Structure Characterization
This entry discusses the problem of describing some communities identified in
a complex network of interest, in a way allowing to interpret them. We suppose
the community structure has already been detected through one of the many
methods proposed in the literature. The question is then to know how to extract
valuable information from this first result, in order to allow human
interpretation. This requires subsequent processing, which we describe in the
rest of this entry
Against Motivational Efficacy of Beliefs
Bromwich (2010) argues that a belief is motivationally efficacious in that, other things being equal, it disposes an agent to answer a question in accordance with that belief. I reply that what we are disposed to do is largely determined by our genes, whereas what we believe is largely determined by stimuli from the environment. We have a standing and default disposition to answer questions honestly, ceteris paribus, even before we are exposed to environmental stimuli. Since this standing and default disposition is innate, and our beliefs have their source in environmental stimuli, our beliefs cannot be the source of the disposition. Moreover, a recent finding in neuroscience suggests that motivation is extrinsic to belief
KCRS: A Blockchain-Based Key Compromise Resilient Signature System
Digital signatures are widely used to assure authenticity and integrity of messages (including blockchain transactions). This assurance is based on assumption that the private signing key is kept secret, which may be exposed or compromised without being detected in the real world. Many schemes have been proposed to mitigate this problem, but most schemes are not compatible with widely used digital signature standards and do not help detect private key exposures. In this paper, we propose a Key Compromise Resilient Signature (KCRS) system, which leverages blockchain to detect key compromises and mitigate the consequences. Our solution keeps a log of valid certificates and digital signatures that have been issued on the blockchain, which can deter the abuse of compromised private keys. Since the blockchain is an open system, KCRS also provides a privacy protection mechanism to prevent the public from learning the relationship between signatures. We present a theoretical framework for the security of the system and a provably-secure construction. We also implement a prototype of KCRS and conduct experiments to demonstrate its practicability
Qualitative Comparison of Community Detection Algorithms
Community detection is a very active field in complex networks analysis,
consisting in identifying groups of nodes more densely interconnected
relatively to the rest of the network. The existing algorithms are usually
tested and compared on real-world and artificial networks, their performance
being assessed through some partition similarity measure. However, artificial
networks realism can be questioned, and the appropriateness of those measures
is not obvious. In this study, we take advantage of recent advances concerning
the characterization of community structures to tackle these questions. We
first generate networks thanks to the most realistic model available to date.
Their analysis reveals they display only some of the properties observed in
real-world community structures. We then apply five community detection
algorithms on these networks and find out the performance assessed
quantitatively does not necessarily agree with a qualitative analysis of the
identified communities. It therefore seems both approaches should be applied to
perform a relevant comparison of the algorithms.Comment: DICTAP 2011, The International Conference on Digital Information and
Communication Technology and its Applications, Dijon : France (2011
Spontaneous fluctuations in liver biochemistries in patients with compensated NASH cirrhosis: Implications for drug hepatotoxicity monitoring
Introduction: Patients with cirrhosis may have spontaneous fluctuations in liver enzymes, which may confound detection of drug-induced liver injury (DILI), but these fluctuations have not been described.
Objective: We sought to quantify spontaneous liver enzyme abnormalities in patients with cirrhosis due to nonalcoholic steatohepatitis (NASH) enrolled in clinical trials.
Methods: We examined the laboratory values of patients with compensated cirrhosis randomized to placebo in two clinical trials for NASH. Patients in one study were followed every 13 weeks up to week 57; patients in the other study were followed every 4 weeks up to week 120.
Results: In total, 53 and 85 patients were randomized to placebo in the trials. Baseline alanine aminotransferase (ALT) was greater than the laboratory upper limit of normal (ULN) in 53% and 49% of participants, aspartate aminotransferase (AST) was > ULN in 49% and 59%, alkaline phosphatase was > ULN in 36% and 27%, and bilirubin was >ULN in 13% and 19%. During follow-up, ALT increased to 2× baseline in 8% and 15%, AST increased to 2× baseline in 6% and 21%, and bilirubin increased to 2× baseline in 9% and 18%. Alkaline phosphatase did not increase to 2× baseline for any patient. The maximum ALT was 3× ULN in 9% and 12%. ALT increased to 3× baseline in three patients and to 5× ULN in two patients. No patients had elevations consistent with Hy's law. The maximum ALT for patients with abnormal baseline values was higher [median 48 U/L (range 34-299) and 56 U/L (47-85)] than for those with normal baseline values [median 26.5 U/L (range 18-33) and 29 U/L (25.5-30.5)] in both studies, respectively, with p < 0.001.
Conclusion: Spontaneous liver enzyme abnormalities are common in patients with NASH cirrhosis in clinical trials, and these abnormalities rarely met criteria for DILI suspicion. Further work to better define these abnormalities and continued vigilance to detect DILI in this population is needed
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