421 research outputs found
Unimodular integer circulants associated with trinomials
The n � n circulant matrix associated with the polynomial [image removed] (with d < n) is the one with first row (a0 ? ad 0 ? 0). The problem as to when such circulants are unimodular arises in the theory of cyclically presented groups and leads to the following question, previously studied by Odoni and Cremona: when is Res(f(t), tn-1) = �1? We give a complete answer to this question for trinomials f(t) = tm � tk � 1. Our main result was conjectured by the author in an earlier paper and (with two exceptions) implies the classification of the finite Cavicchioli?Hegenbarth?Repov? generalized Fibonacci groups, thus giving an almost complete answer to a question of Bardakov and Vesnin
On the molecules of numerical semigroups, Puiseux monoids, and Puiseux algebras
A molecule is a nonzero non-unit element of an integral domain (resp.,
commutative cancellative monoid) having a unique factorization into
irreducibles (resp., atoms). Here we study the molecules of Puiseux monoids as
well as the molecules of their corresponding semigroup algebras, which we call
Puiseux algebras. We begin by presenting, in the context of numerical
semigroups, some results on the possible cardinalities of the sets of molecules
and the sets of reducible molecules (i.e., molecules that are not
irreducibles/atoms). Then we study the molecules in the more general context of
Puiseux monoids. We construct infinitely many non-isomorphic atomic Puiseux
monoids all whose molecules are atoms. In addition, we characterize the
molecules of Puiseux monoids generated by rationals with prime denominators.
Finally, we turn to investigate the molecules of Puiseux algebras. We provide a
characterization of the molecules of the Puiseux algebras corresponding to
root-closed Puiseux monoids. Then we use such a characterization to find an
infinite class of Puiseux algebras with infinitely many non-associated
reducible molecules.Comment: 21 pages, 2 figure
The Increase of the Micoporosity and CO2 Adsorption Capacity of the Commercial Activated Carbon CWZ-22 by KOH Treatment
The chemical modification of CWZ-22—commercial activated carbon (AC) with KOH‐ to enhance CO2 adsorption was examined. The effect of different impregnation ratios KOH:CWZ-22 from 1 to 4 was studied. The ACs were characterized by CO2 and N2 sorption, Fourier transform infrared (FTIR), SEM, and XRD methods
On certain infinite extensions of the rationals with Northcott property
A set of algebraic numbers has the Northcott property if each of its subsets
of bounded Weil height is finite. Northcott's Theorem, which has many
Diophantine applications, states that sets of bounded degree have the Northcott
property. Bombieri, Dvornicich and Zannier raised the problem of finding fields
of infinite degree with this property. Bombieri and Zannier have shown that
\IQ_{ab}^{(d)}, the maximal abelian subfield of the field generated by all
algebraic numbers of degree at most , is such a field. In this note we give
a simple criterion for the Northcott property and, as an application, we deduce
several new examples, e.g.
\IQ(2^{1/d_1},3^{1/d_2},5^{1/d_3},7^{1/d_4},11^{1/d_5},...) has the Northcott
property if and only if
tends to infinity
Ground states for a class of deterministic spin models with glassy behaviour
We consider the deterministic model with glassy behaviour, recently
introduced by Marinari, Parisi and Ritort, with \ha\ , where is the discrete sine Fourier transform. The
ground state found by these authors for odd and prime is shown to
become asymptotically dege\-ne\-ra\-te when is a product of odd primes,
and to disappear for even. This last result is based on the explicit
construction of a set of eigenvectors for , obtained through its formal
identity with the imaginary part of the propagator of the quantized unit
symplectic matrix over the -torus.Comment: 15 pages, plain LaTe
Recommended from our members
The structure of blocks with a Klein four defect group
We prove Erdmann’s conjecture [16] stating that every block with a Klein four defect group has a simple module with trivial source, and deduce from this that Puig’s finiteness conjecture holds for source algebras of blocks with a Klein four defect group. The proof uses the classification of finite simple groups
How to treat hypertension more effectively? Patients’ education program in Polish Project of 400 Cities
Wstęp Nadciśnienie tętnicze stanowi najczęstszą patologię
układu krążenia. Skuteczność leczenia, pomimo
dostępności sprawdzonych metod, jest nadal
wysoko niezadowalająca. Chorzy na nadciśnienie tętnicze
obarczeni są szczególnie wysokim ryzykiem
powikłań sercowo-naczyniowych. Jedną z głównych
przyczyn nieskuteczności leczenia jest brak współpracy
pacjenta z lekarzem. PP400M to wieloośrodkowy
projekt interwencyjny i badawczy, mający na
celu poprawę wykrywania i skuteczności terapii najczęstszych
czynników ryzyka chorób układu sercowo-
naczyniowego oraz poszerzenie wiedzy na temat
zdrowego żywienia. Celem badania była ocena skuteczności
programu edukacji realizowanego wśród
pacjentów dotychczas nieleczonych, z niedawno wykrytym
nadciśnieniem tętniczym oraz zaburzeniami
gospodarki lipidowej i węglowodanowej.
Materiał i metody W 268 miejscowościach, liczących
poniżej 8000 mieszkańców, w latach 2003-2005 przeprowadzono
zajęcia edukacyjne dla 10 720 pacjentów
z nowo wykrytym nadciśnieniem lub zaburzeniami
metabolicznymi. W każdym z tych ośrodków
utworzono i przeszkolono zespół edukacyjny, składający
się z lekarza i pielęgniarki. Edukacja nowo
wykrytych chorych prowadzona była przez zespoły
edukatorskie w ośmioosobowych grupach. Wyszkolone
w programie zespoły edukacyjne po zakończeniu
realizacji programu mogą dalej uczyć pacjentów,
używając przekazanych nieodpłatnie pomocy
edukacyjnych. Analizą skuteczności programu objęto 10 720 pacjentów (kobiety 66,39%, mężczyźni 33,61%,
śr. wiek 59,39 ± 13,2 roku, BMI 27,95 ± 5,13 kg/m2,
śr. RR 147,75 ± 27,393/90,82 ± 13,602 mm Hg).
Wyniki Większość chorych z niedawno wykrytym
nadciśnieniem oczekuje informacji na temat chorób
układu krążenia (91%), a jedynie 9% ocenia swoją
wiedzę jako wystarczającą. Po zajęciach edukacyjnych
większość pacjentów chciałaby mieć wpływ na
swoje leczenie (90,77%) oraz deklaruje chęć wykonywania
pomiarów tętniczych w domu (92,52%). Ponad
90% zdaje sobie sprawę iż pomiary wykonywane
w domu mają znaczenie w leczeniu nadciśnienia tętniczego.
Po przeprowadzeniu szkolenia wzrósł poziom
wiedzy na temat czynników ryzyka chorób
układu krążenia, jak również wpływu ich modyfikacji
na skuteczność leczenia nadciśnienia tętniczego.
W wyniku przeprowadzonych zajęć edukacyjnych
zaobserwowano wzrost poziomu wiedzy pacjentów
na temat zasad postępowania farmakologicznego;
58,51% pacjentów przed edukacją zanegowało
stwierdzenie, że prawidłowe ciśnienie tętnicze
w trakcie leczenia usprawiedliwia odstawienie przepisanego
leku, po edukacji - 76,20%. Zaobserwowano
wzrost świadomości pacjentów na temat występowania
potencjalnych działań niepożądanych.
Wnioski Istnieje duże zapotrzebowanie na informacje
dotyczące chorób układu krążenia wśród osób
z noworozpoznanymi zaburzeniami - nadciśnieniem
tętniczym i zaburzeniami gospodarki lipidowej
i węglowodanowej. Pacjenci z dopiero co rozpoznanym
nadciśnieniem tętniczym dobrze identyfikują
czynniki ryzyka chorób układu krążenia, jednak
poziom ich wiedzy o zasadach farmakoterapii jest
niewystarczający. Edukacja pacjentów jest skutecznym
narzędziem, pomagającym przekazać i rozszerzyć
wiadomości na temat choroby, czynników ryzyka
i sposobów terapii.Background Hypertension is the most common cardiovascular
pathology. Treatment efficacy, despite effective methods,
is still highly unsatisfactory. Hypertensive patients are
at high risk of cardiovascular complications. One of the
reasons for treatment poor effects is lack of patient-doctor
cooperation.
PP400M is multicenter, intervention and research project
which aim was to improve efficacy of screening and reduction
of major cardiovascular risk factors and improvement
of healthy diet knowledge. The aim of the study was to
evaluate effectiveness of educational program designed for
newly diagnosed patients with hypertension, dyslipidaemia
and glucose intolerance.
Material and methods In 268 small cities and villages of
up to 8000 habitants in years 2003-2005 the educational
program was implemented. 10 720 patients with newly
diagnosed metabolic disturbances were invited to participate
in education program. The meetings were held by
teams of nurse and a physician.
The eight people groups met during two meetings, held
weekly. The first meeting was devoted to risk factors, diet and self blood pressure measurement, during second meeting
the rules of hypertension pharmacotherapy were discussed.
Teams instructed to implement the program were
given free educational materials to continue with the program
later.
Participants in education meetings 66.39% were women and
33.61% men. The efficacy analysis was performed on 10 720
patients (mean age 59.39 ± 13.2 ys., BMI 27.95 ± 5.13 kg/m2,
mean RR 147.75 ± 27.393/90.82 ± 13.602 mm Hg).
Results Most patients (91%) with newly diagnosed hypertension
expect to be offered more information on cardiovascular
diseases, only 9% asses their knowledge as good.
After education meetings most of the patients (90.77%)
want to be involved in treatment process, and declare the
will to perform blood pressure measurement at home
(92.52%). More than 90% of patients realize that home
blood pressure measurement is important in hypertension
management. After education knowledge level on risk factors
increases as well as awareness on importance of lifestyle
modification in treatment of hypertension. After education
there is a marked improvement in knowledge on
hypertension pharmacotherapy rules. We also observed increase
of side effects awareness among patients after education
meetings.
Conclusions There is a strong need for information concerning
cardiovascular diseases among newly diagnosed patients
with hypertension, dyslipidaemia and glucose intolerance.
Newly diagnosed patients identify well cardiovascular risk
factors, but knowledge about pharmacotherapy rules is very poor. Patient education is an effective tool in improving
patients knowledge on disease, risk factors and methods of
therapy
V*-algebras, independence algebras and logic
Independence algebras were introduced in the early 1990s by specialists in semigroup theory, as a tool to explain similarities between the transformation monoid on a set and the endomorphism monoid of a vector space. It turned out that these algebras had already been defined and studied in the 1960s, under the name of v*-algebras, by specialists in universal algebra (and statistics). Our goal is to complete this picture by discussing how, during the middle period, independence algebras began to play a very important role in logic
Abnormalities in autonomic function in obese boys at-risk for insulin resistance and obstructive sleep apnea.
Study objectivesCurrent evidence in adults suggests that, independent of obesity, obstructive sleep apnea (OSA) can lead to autonomic dysfunction and impaired glucose metabolism, but these relationships are less clear in children. The purpose of this study was to investigate the associations among OSA, glucose metabolism, and daytime autonomic function in obese pediatric subjects.MethodsTwenty-three obese boys participated in: overnight polysomnography; a frequently sampled intravenous glucose tolerance test; and recordings of spontaneous cardiorespiratory data in both the supine (baseline) and standing (sympathetic stimulus) postures.ResultsBaseline systolic blood pressure and reactivity of low-frequency heart rate variability to postural stress correlated with insulin resistance, increased fasting glucose, and reduced beta-cell function, but not OSA severity. Baroreflex sensitivity reactivity was reduced with sleep fragmentation, but only for subjects with low insulin sensitivity and/or low first-phase insulin response to glucose.ConclusionsThese findings suggest that vascular sympathetic activity impairment is more strongly affected by metabolic dysfunction than by OSA severity, while blunted vagal autonomic function associated with sleep fragmentation in OSA is enhanced when metabolic dysfunction is also present
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