3,146 research outputs found
The Global Crisis with States Incapable of Minimax
Global attention is now very much directed onto questions of war and military armaments. In a long run perspective on humankind in the 21st century, global warming raises an even more fundamental problem of human survival. By heating the planet through greenhouse gases, especially CO2 and methane, rich countries risk their affluence and poor countries will be even worse
The structure of decomposition of a triconnected graph
We describe the structure of triconnected graph with the help of its
decomposition by 3-cutsets. We divide all 3-cutsets of a triconnected graph
into rather small groups with a simple structure, named complexes. The detailed
description of all complexes is presented. Moreover, we prove that the
structure of a hypertree could be introduced on the set of all complexes. This
structure gives us a complete description of the relative disposition of the
complexes.
Keywords: connectivity, triconneted graphs.Comment: 49 pages, 8 figures. Russian version published in Zap. Nauchn. Sem.
POMI v.391 (2011), http://www.pdmi.ras.ru/znsl/2011/v391/abs090.htm
A novel isolator-based system promotes viability of human embryos during laboratory processing
In vitro fertilisation (IVF) and related technologies are arguably the most challenging of all cell culture applications. The starting material is a single cell from which one aims to produce an embryo capable of establishing a pregnancy eventually leading to a live birth. Laboratory processing during IVF treatment requires open manipulations of gametes and embryos, which typically involves exposure to ambient conditions. To reduce the risk of cellular stress, we have developed a totally enclosed system of interlinked isolator-based workstations designed to maintain oocytes and embryos in a physiological environment throughout the IVF process. Comparison of clinical and laboratory data before and after the introduction of the new system revealed that significantly more embryos developed to the blastocyst stage in the enclosed isolator-based system compared with conventional open-fronted laminar flow hoods. Moreover, blastocysts produced in the isolator-based system contained significantly more cells and their development was accelerated. Consistent with this, the introduction of the enclosed system was accompanied by a significant increase in the clinical pregnancy rate and in the proportion of embryos implanting following transfer to the uterus. The data indicate that protection from ambient conditions promotes improved development of human embryos. Importantly, we found that it was entirely feasible to conduct all IVF-related procedures in the isolator-based workstations
The diagnosis of mental disorders: the problem of reification
A pressing need for interrater reliability in the diagnosis of mental disorders
emerged during the mid-twentieth century, prompted in part by
the development of diverse new treatments. The Diagnostic and Statistical
Manual of Mental Disorders (DSM), third edition answered this need
by introducing operationalized diagnostic criteria that were field-tested
for interrater reliability. Unfortunately, the focus on reliability came at a
time when the scientific understanding of mental disorders was embryonic
and could not yield valid disease definitions. Based on accreting
problems with the current DSM-fourth edition (DSM-IV) classification,
it is apparent that validity will not be achieved simply by refining
criteria for existing disorders or by the addition of new disorders. Yet
DSM-IV diagnostic criteria dominate thinking about mental disorders
in clinical practice, research, treatment development, and law. As a result,
the modernDSMsystem, intended to create a shared language, also
creates epistemic blinders that impede progress toward valid diagnoses.
Insights that are beginning to emerge from psychology, neuroscience,
and genetics suggest possible strategies for moving forward
On coalgebras with internal moves
In the first part of the paper we recall the coalgebraic approach to handling
the so-called invisible transitions that appear in different state-based
systems semantics. We claim that these transitions are always part of the unit
of a certain monad. Hence, coalgebras with internal moves are exactly
coalgebras over a monadic type. The rest of the paper is devoted to supporting
our claim by studying two important behavioural equivalences for state-based
systems with internal moves, namely: weak bisimulation and trace semantics.
We continue our research on weak bisimulations for coalgebras over order
enriched monads. The key notions used in this paper and proposed by us in our
previous work are the notions of an order saturation monad and a saturator. A
saturator operator can be intuitively understood as a reflexive, transitive
closure operator. There are two approaches towards defining saturators for
coalgebras with internal moves. Here, we give necessary conditions for them to
yield the same notion of weak bisimulation.
Finally, we propose a definition of trace semantics for coalgebras with
silent moves via a uniform fixed point operator. We compare strong and weak
bisimilation together with trace semantics for coalgebras with internal steps.Comment: Article: 23 pages, Appendix: 3 page
From Nonspecific DNA–Protein Encounter Complexes to the Prediction of DNA–Protein Interactions
©2009 Gao, Skolnick. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.doi:10.1371/journal.pcbi.1000341DNA–protein interactions are involved in many essential biological activities. Because there is no simple mapping code between DNA base pairs and protein amino acids, the prediction of DNA–protein interactions is a challenging problem. Here, we present a novel computational approach for predicting DNA-binding protein residues and DNA–protein interaction modes without knowing its specific DNA target sequence. Given the structure of a DNA-binding protein, the method first generates an ensemble of complex structures obtained by rigid-body docking with a nonspecific canonical B-DNA. Representative models are subsequently selected through clustering and ranking by their DNA–protein interfacial energy. Analysis of these encounter complex models suggests that the recognition sites for specific DNA binding are usually favorable interaction sites for the nonspecific DNA probe and that nonspecific DNA–protein interaction modes exhibit some similarity to specific DNA–protein binding modes. Although the method requires as input the knowledge that the protein binds DNA, in benchmark tests, it achieves better performance in identifying DNA-binding sites than three previously established methods, which are based on sophisticated machine-learning techniques. We further apply our method to protein structures predicted through modeling and demonstrate that our method performs satisfactorily on protein models whose root-mean-square Ca deviation from native is up to 5 Å from their native structures. This study provides valuable structural insights into how a specific DNA-binding protein interacts with a nonspecific DNA sequence. The similarity between the specific DNA–protein interaction mode and nonspecific interaction modes may reflect an important sampling step in search of its specific DNA targets by a DNA-binding protein
Bayesian Based Comment Spam Defending Tool
Spam messes up user's inbox, consumes network resources and spread worms and
viruses. Spam is flooding of unsolicited, unwanted e mail. Spam in blogs is
called blog spam or comment spam.It is done by posting comments or flooding
spams to the services such as blogs, forums,news,email archives and guestbooks.
Blog spams generally appears on guestbooks or comment pages where spammers fill
a comment box with spam words. In addition to wasting user's time with unwanted
comments, spam also consumes a lot of bandwidth. In this paper, we propose a
software tool to prevent such blog spams by using Bayesian Algorithm based
technique. It is derived from Bayes' Theorem. It gives an output which has a
probability that any comment is spam, given that it has certain words in it.
With using our past entries and a comment entry, this value is obtained and
compared with a threshold value to find if it exceeds the threshold value or
not. By using this concept, we developed a software tool to block comment spam.
The experimental results show that the Bayesian based tool is working well.
This paper has the major findings and their significance of blog spam filter.Comment: 14 Pages,4 Figures, International Journal of Network Security & Its
Applications (IJNSA), Vol.2, No.4, October 201
Endovascular Management of Iliofemoral Deep Venous Thrombosis due to Iliac Vein Compression Syndrome in Patients with Protein C and/or S Deficiency
The purpose of this study was to evaluate the early outcome of endovascular management in patients with iliofemoral deep venous thrombosis (DVT) due to iliac vein compression syndrome (IVCS) and protein C and/or S deficiency. Between September 2000 and January 2003, catheter-directed thrombolysis was performed in 11 patients with a diagnosis of acute iliofemoral DVT: 7 with protein C and/or S deficiency and 4 without protein C and/or S deficiency. After thrombolysis, the diagnosis of IVCS was confirmed in 6 patients: 4 with protein C and/or S deficiency and 2 without protein C and/or S deficiency. Further intervention consisted of angioplasty and stent placement was performed. Four patients with IVCS and protein C and/or S deficiency were included in this study. The immediate technical and clinical success rates were 100% in all 4 patients. There were no complications or clinically detectable pulmonary emboli. This initial experience suggests that endovascular management of iliofemoral DVT due to IVCS in patients with protein C and/or S deficiency is safe and effective
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