842 research outputs found
Construction of a 3-Dimensional MDS code
In this paper, we describe a procedure for constructing --ary
--MDS codes, of length (for odd) or (for
even), using a set of non--degenerate Hermitian forms in .Comment: 8 Pages Minor typesetting changes; dedicatio
A characterization of Hermitian varieties as codewords
It is known that the Hermitian varieties are codewords in the code defined by
the points and hyperplanes of the projective spaces . In finite
geometry, also quasi-Hermitian varieties are defined. These are sets of points
of of the same size as a non-singular Hermitian variety of
, having the same intersection sizes with the hyperplanes of
. In the planar case, this reduces to the definition of a unital. A
famous result of Blokhuis, Brouwer, and Wilbrink states that every unital in
the code of the points and lines of is a Hermitian curve. We prove
a similar result for the quasi-Hermitian varieties in , ,
as well as in , prime, or , prime, and
An algorithm for constructing some maximal arcs in \PG(2,q^2)
In 1974, J. Thas constructed a new class of maximal arcs for the Desarguesian
plane of order . The construction relied upon the existence of a regular
spread of tangent lines to an ovoid in \PG(3,q) and, in particular, it does
apply to the Suzuki--Tits ovoid. In this paper, we describe an algorithm for
obtaining a possible representation of such arcs in \PG(2,q^2).Comment: 17 page
Lipid and glycemic profiles in patients with bipolar disorder: Cholesterol levels are reduced in mania
none10Background and Objectives: Bipolar disorder (BD) is a severe mental condition with a lifetime prevalence estimated around 2% among the general population. Due to risk factors, etiological mechanisms, and the chronic use of psychotropic medications, people with BD are frequently affected by medical comorbidities, such as metabolic syndrome (MetS), associated with altered blood levels of glucose, cholesterol, and triglycerides. Moreover, the lipid concentration may be associated with the severity of psychiatric symptoms. Materials and Methods: Five hundred and forty-two in-and outpatients (418 affected by BD and 124 affected by schizophrenia) were recruited in two Italian university hospitals. A blood examination assessing the fasting glucose, total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides was performed. Results: No significant differences were found in the lipid and glycemic profiles between patients with BD and schizophrenia. When considering only the BD sample, we found that patients experiencing a manic episode had significantly lower total cholesterol, HDL, and LDL than euthymic patients. Moreover, the total and LDL cholesterol levels were significantly lower in (hypo)manic than depressed patients. Mood episodes did not influence the triglyceride and glucose levels in our sample. Conclusions: Clinicians should pay attention to blood cholesterol levels in patients with BD, as differences in concentrations may predispose them to severe medical conditions and can be associated with the onset of mood episodes.openFusar-Poli L.; Amerio A.; Cimpoesu P.; Natale A.; Salvi V.; Zappa G.; Serafini G.; Amore M.; Aguglia E.; Aguglia A.Fusar-Poli, L.; Amerio, A.; Cimpoesu, P.; Natale, A.; Salvi, V.; Zappa, G.; Serafini, G.; Amore, M.; Aguglia, E.; Aguglia, A
An alternative construction of B-M and B-T unitals in Desarguesian planes
We present a new construction of non-classical unitals from a classical
unital in . The resulting non-classical unitals are B-M unitals.
The idea is to find a non-standard model of with the
following three properties: 1. points of are those of ; 2.
lines of are certain lines and conics of ; 3. the points in
form a non-classical B-M unital in .
Our construction also works for the B-T unital, provided that conics are
replaced by certain algebraic curves of higher degree.Comment: Keywords: unital, desarguesian plane 11 pages; ISSN: 0012-365
A geometric proof of the upper bound on the size of partial spreads in H(4n+1, q²)
We give a geometric proof of the upper bound of q(2n+1) + 1 on the size of partial spreads in the polar space H(4n + 1, q(2)). This bound is tight and has already been proved in an algebraic way. Our alternative proof also yields a characterization of the partial spreads of maximum size in H(4n + 1, q(2))
Hyper/neuroinflammation in COVID-19 and suicide etiopathogenesis: Hypothesis for a nefarious collision?
open13Accumulating scientific and clinical evidence highlighted pathological hyperinflammation as a cardinal feature of SARS-CoV-2 infection and acute COVID-19 disease. With the emergence of long COVID-19 syndrome, several chronic health consequences, including neuropsychiatric sequelae, have gained attention from the public and medical communities. Since inflammatory mediators have also been accredited as putative biomarkers of suicidal ideations and behaviors, hyper- and neuroinflammation might share some colliding points, overlapping and being interconnected in the context of COVID-19. This review aims to provide a summary of current knowledge on the molecular and cellular mechanisms of COVID-19-associated hyper/neuroinflammation with focus on their relevance to the inflammatory hypothesis of suicide development. Subsequently, strategies to alleviate COVID-19 hyper/neuroinflammation by immunomodulatory agents (many of which at experimental stages) as well as psychopharmacologic/psychotherapeutic approaches are also mentioned. While suicide risk in COVID-19 survivors - until now little known - needs further analysis through longitudinal studies, current observations and mechanistic postulates warrant additional attention to this possibly emerging mental health concern.openCostanza, A.; Amerio, A.; Aguglia, A.; Serafini, G.; Amore, M.; Hasler, R.; Ambrosetti, J.; Bondolfi, G.; Sampogna, G.; Berardelli, I.; Fiorillo, A.; Pompili, M.; Nguyen, K.D.Costanza, A.; Amerio, A.; Aguglia, A.; Serafini, G.; Amore, M.; Hasler, R.; Ambrosetti, J.; Bondolfi, G.; Sampogna, G.; Berardelli, I.; Fiorillo, A.; Pompili, M.; Nguyen, K. D
ORBIT CODES FROM FORMS ON VECTOR SPACES OVER A FINITE FIELD
In this paper we construct different families of orbit codes in the vector spaces of the symmetric bilinear forms, quadratic forms and Hermitian forms on an n-dimensional vector space over the finite field Fq. All these codes admit the general linear group GL(n, q) as a transitive automorphism group
Effect of Housing Quality on the Mental Health of University Students during the COVID-19 Lockdown
COVID-19 outbreak imposed rapid and severe public policies that consistently impacted the lifestyle habits and mental health of the general population. Despite vaccination, lockdown restrictions are still considered as potential measures to contrast COVID-19 variants spread in several countries. Recent studies have highlighted the impacts of lockdowns on the population\u2019s mental health; however, the role of the indoor housing environment where people spent most of their time has rarely been considered. Data from 8177 undergraduate and graduate students were collected in a large, cross-sectional, web-based survey, submitted to a university in Northern Italy during the first lockdown period from 1 April to 1 May 2020. Logistic regression analysis showed significant associations between moderate and severe depression symptomatology (PHQ-9 scores 65 15), and houses with both poor indoor quality and small dimensions (OR = 4.132), either medium dimensions (OR = 3.249) or big dimensions (OR = 3.522). It was also found that, regardless of housing size, poor indoor quality is significantly associated with moderate\u2013severe depressive symptomatology. Further studies are encouraged to explore the long-term impact of built environment parameter modifications on mental health, and therefore support housing and public health policies
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