Abstract:
The identification of mechanisms that mediate stress-induced hippocampal damage may shed new light into the pathophysiology of depressive disorders and provide new targets for therapeutic intervention. We focused on the secreted glycoprotein Dickkopf-1 (Dkk-1), an inhibitor of the canonical Wnt pathway, involved in neurodegeneration. Mice exposed to mild restraint stress showed increased hippocampal levels of Dkk-1 and reduced expression of β-catenin, an intracellular protein positively regulated by the canonical Wnt signalling pathway. In adrenalectomized mice, Dkk-1 was induced by corticosterone injection, but not by exposure to stress. Corticosterone also induced Dkk-1 in mouse organotypic hippocampal cultures and primary cultures of hippocampal neurons and, at least in the latter model, the action of corticosterone was reversed by the type-2 glucocorticoid receptor antagonist mifepristone. To examine whether induction of Dkk-1 was causally related to stress-induced hippocampal damage, we used doubleridge mice, which are characterized by a defective induction of Dkk-1. As compared to control mice, doubleridge mice showed a paradoxical increase in basal hippocampal Dkk-1 levels, but no Dkk-1 induction in response to stress. In contrast, stress reduced Dkk-1 levels in doubleridge mice. In control mice, chronic stress induced a reduction in hippocampal volume associated with neuronal loss and dendritic atrophy in the CA1 region, and a reduced neurogenesis in the dentate gyrus. Doubleridge mice were resistant to the detrimental effect of chronic stress and, instead, responded to stress with increases in dendritic arborisation and neurogenesis. Thus, the outcome of chronic stress was tightly related to changes in Dkk-1 expression in the hippocampus. These data indicate that induction of Dkk-1 is causally related to stress-induced hippocampal damage and provide the first evidence that Dkk-1 expression is regulated by corticosteroids in the central nervous system. Drugs that rescue the canonical Wnt pathway may attenuate hippocampal damage in major depression and other stress-related disorders.

Abstract:
These procedures yielded a total of 136 tester-specific SFs of which 85 were APEC-derived and 51 were UPEC-derived. Most of the APEC-derived SFs were associated with plasmids; whereas, the majority of UPEC-derived sequences matched to the bacterial chromosome. We further determined the distribution of these tester-derived sequences in a collection of UPEC and APEC isolates using polymerase chain reaction techniques. Plasmid-borne, APEC-derived sequences (tsh, cvaB, traR, traC and sopB) were predominantly present in APEC, as compared to UPEC. Of the UPEC-derived SFs, those encoding hemolysin D and F1C major and minor fimbrial subunits were present only in UPEC. However, two UPEC-derived SFs that showed strong similarity to the uropathgenic-specific protein gene (usp) occurred in APEC, demonstrating that usp is not specific to UPEC.This study provides evidence of the genetic variability of ExPEC as well as genomic similarities between UPEC and APEC; it did not identify any single marker that would dictate host and/or niche specificity in APEC or UPEC. However, further studies on the genes that encode putative or hypothetical proteins might offer important insight into the pathogenesis of disease, as caused by these two ExPEC.Extraintestinal pathogenic Escherichia coli (ExPEC) are a specific group of E. coli that cause a diverse spectrum of invasive infections in animals and humans often leading to septicemia [1,2]. Among the typical extraintestinal infections caused by ExPEC in humans are urinary tract infections (UTIs), which are a major public health concern in developed countries costing healthcare systems billions of dollars annually [3-5]. Similarly, colibacillosis, caused by avian ExPEC isolates (avian pathogenic E. coli or APEC), is an economically devastating disease to poultry industries worldwide [1,6].Both APEC and human ExPEC, implicated in UTIs (uropathogenic E. coli or UPEC), are similar in that they both possess a common set of virulence markers such as

Abstract:
The level of air quality in urban centres is affected by emission of several pollutants, mainly coming from the vehicles flowing in their road networks. This is a well known phenomenon that influences the quality of life of people. Despite the deep concern of researchers and technicians, we are far from a total understanding of this phenomenon. On the contrary, the availability of reliable forecasting models would constitute an important tool for administrators in order of assessing suitable actions concerning the transportation policies, public as well private. Referring to the situation of the running fleet and the measured pollutant concentrations concerning the Italian town of Palermo, a data-deduced traffic model is here derived, its truthfulness being justified by a fuzzyfication of the phenomenon. A first validation of the model is supplied by utilising the emissions characteristics and the pollutant concentrations referring to a two years period of time. This work could represent a first attempt in defining a new approach to the problem of the pollution of the urban contexts, in order of providing administrators with a reliable and easier tool.

The worldwide
increase of the publications concerning the assessment of marine renewable
living resources is highlighting long-standing problems with symbols and
annotations. Starting from the symbols presented within the classic
fisheries masterpieces produced, mainly in the fifty of the last century, a
first “Milestone” list was organised. Thereafter, the pertinent literature
was (not exhaustively) browsed in order to integrate this Milestone list on the
base of a set of decisional criteria. The present contribution consists in
using the Latin letters as well established symbols for the corresponding parameters,
leaving free to specific use (with few historical exceptions) the Greek letters
in view to open a discussion among all the fisheries scientists and bodies in
order to move towards a common language and better communication standards.

Abstract:
In this paper, we study the k–Lucas numbers of arithmetic indexes of the form an+r , where n is a natural number and r is less than r. We prove a formula for the sum of these numbers and particularly the sums of the first k-Lucas numbers, and then for the even and the odd k-Lucas numbers. Later, we find the generating function of these numbers. Below we prove these same formulas for the alternated k-Lucas numbers. Then, we prove a relation between the k–Fibonacci numbers of indexes of the form 2rn and the k–Lucas numbers of indexes multiple of 4. Finally, we find a formula for the sum of the square of the k-Fibonacci even numbers by mean of the k–Lucas numbers.

The
atmospheric behaviour of air is largely governed by low and high pressure
systems. However, the relationship between these systems is not linear, as
winds, sea temperatures and solar intensity modulate their dynamics and reduce
predictability. Several other factors are known to affect these atmospheric
dynamics, such as solar cycles. Recent evidence shows however that the earth’s
gravitational field can be quantized in terms of quantum numbers, as recently
published in Nature. The implications of this relationship between gravity and
quantum numbers give rise to the possible key role of a quantum behaviour of
gravity in affecting the formation of high- and low-pressure systems. In this
letter, the author suggests a relation between the recently observed quantized
nature of gravity, the weight of air and the formation of Low and High pressure
areas in the atmosphere. The theory is novel and can aid in the understanding
of interplay between the earths core forces, the gravitational behaviour and
the atmospheric dynamics. There are however several parts of this theory that
need further development, and an initial expression of this putative
relationship is introduced.

Abstract:
In this paper, we will see that
some k -Fibonacci sequences
are related to the classical Fibonacci sequence of such way that we can express the terms of a k -Fibonacci sequence in function of some terms of the
classical Fibonacci sequence. And the formulas will
apply to any sequence of a certain set of k' -Fibonacci sequences. Thus we find k -Fibonacci sequences relating to other k -Fibonacci sequences when σ'_{k} is linearly dependent of .

Proposed here is a new framework for the analysis of
complex systems as a non-explicitly programmed mathematical hierarchy of
subsystems using only the fundamental principle of causality, the mathematics
of groupoid symmetries, and a basic causal metric needed to support measurement
in Physics. The complex system is described as a discrete set S of state variables. Causality is
described by an acyclic partial order w on S, and is considered as a
constraint on the set of allowed state transitions. Causal set (S, w)
is the mathematical model of the system. The dynamics it describes is
uncertain. Consequently, we focus on invariants, particularly group-theoretical
block systems. The symmetry of S by
itself is characterized by its symmetric group, which generates a trivial block
system over S. The constraint of
causality breaks this symmetry and degrades it to that of a groupoid, which may
yield a non-trivial block system on S.
In addition, partial order w determines a partial order for the blocks, and the set of blocks becomes a
causal set with its own, smaller block system. Recursion yields a multilevel
hierarchy of invariant blocks over S with the properties of a scale-free mathematical fractal. This is the invariant
being sought. The finding hints at a deep connection between the principle of
causality and a class of poorly understood phenomena characterized by the
formation of hierarchies of patterns, such as emergence, selforganization, adaptation, intelligence, and semantics.
The theory and a thought experiment are discussed and previous evidence is
referenced. Several predictions in the human brain are confirmed with wide
experimental bases. Applications are anticipated in many disciplines, including
Biology, Neuroscience, Computation, Artificial Intelligence, and areas of
Engineering such as system autonomy, robotics, systems integration, and image
and voice recognition.

Abstract:
This study presents an axisymmetric solution of the Einstein equations for empty space. The geometry is studied by determining its Petrov classification and killing vectors. Light propagation, orbital motion and asymptotic and Newtonian limits are also studied. Additionally, cosmological applications of the geometry are also outlined as an alternative model for the inflationary universe and as a substitute for dark matter and quintessence.