bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental and computational investigations of a cadmium(II) mononuclear complex with 2,6-Bis(3,5-dimethyl-N-pyrazolyl)pyridine (bdmpp) and selenocyanate as ligands
Authors: Odabaşıoğlu Sinem , Kurtaran Raif , Azizoglu Akin , Kara Hülya , Öz Sevi , Atakol Orhan 
Published: May 2009

Abstract
A new cadmium (II) complex, [Cd(bdmpp)(SeCN)2(H2O)] (1) (where bdmpp = 2,6-bis(3,5-dimethyl-N-pyrazolyl)pyridine), has been synthesized and characterized by elemental and spectral (IR, 1H-NMR and 13C-NMR, UV-Vis) analyses, differential scanning calorimetry, and single crystal X-ray diffraction studies. X-ray analysis showed that the structure was crystallized in the monoclinic space group Cc with a = 9.031(2), b = 13.884(3), c = 16.910(3) Å, and Z = 4. The geometry around the cadmium atom is distorted octahedral with a CdN3Se2O setup. The N atoms of the SeCN are engaged in two strong intermolecular H-bonding interactions forming a 3D supramolecular polymeric network. The geometry and vibrational frequencies of complex 1 computed with the DFT methods (BLYP, B3LYP, B3PW91, MPW1PW91) are in better agreement with experiment than those obtained with the ab-initio method except for the bond angles. The molecular orbital diagram has been also calculated and visualized at the B3LYP/LanL2DZ level of theory.
Comparison of perchloroethylene extraction techniques in soil gas survey quantification
Authors: Zdravkov B. , Kubal M. , Janků J. 
Published: May 2009

Abstract
Subsurface pollution by volatile organic compounds has emerged as a widespread problem in industrialized countries. This study compares static headspace technique and methanol extraction/purge-and-trap analysis followed by thermal desorption/gas chromatography in attempts for quantification of gas survey results in the determination of these chemicals in soil. Several soils were contaminated with aqueous solution of perchloroethylene (PCE) (140 mg L−1) using a vapor treatment method. Soil spiking took place up to 24 h in desiccator by exposing individual soil samples contained in open 40 mL glass vials to PCE evaporated from the solution. After exposure the samples were stored and analyzed within 2 days. The achieved results strongly suggest that gas extraction can provide quantitative results, regarding PCE concentration in soils, which are not significantly different from liquid based extraction analysis.
The effects of copper ions on the catalytical degradation of azo dye acid chrome blue K
Authors: Liu Xiang-Hu , Lin Jing , Gao Hong-Wen , Zhang Ya-Lei 
Published: May 2009

Abstract
The effects of Cu2+ on the catalytical degradation of acid chrome blue K (ACBK) in UV-TiO2 and H2O2 processes were studied. In these two processes, Cu2+ markedly depressed the catalytical degradation of ACBK by its interaction with ACBK. Through this interaction, the new complex Cu(ACBK)2 formed. The formation of this new complex was favorable to protect some groups in ACBK from the oxidation of reactive oxygen generated in UV-TiO2 and H2O2 processes, and consequently had suppressing effects on degradation of ACBK. In addition, Cu2+ also inhibited the degradation of ACBK in UV-TiO2 process by influencing the adsorption of ACBK on the surface of TiO2 particles.
QSPR study for the prediction of half-wave potentials of benzoxazines by heuristic method and radial basis function neural network
Authors: Liu Huitao , Wen Yingying , Luan Feng , Gao Yuan , Li Xiuyong 
Published: May 2009

Abstract
The half-wave potential (E1/2) is an important electrochemical property of organic compounds. In this work, a quantitative structure-property relationship (QSPR) analysis has been conducted on the half-wave reduction potential (E1/2) of 40 substituted benzoxazines by means of both a heuristic method (HM) and a non-linear radial basis function neural network (RBFNN) modeling method. The statistical parameters provided by the HM model (R2 =0.946; F=152.576; RMSCV=0.0141) and the RBFNN model (R2=0.982; F=1034.171 and RMS =0.0209) indicated satisfactory stability and predictive ability. The obtained models showed that benzoxazines with larger Min valency of a S atom (MVSA), lower Relative number of H atom (RNHA) and Min n-n repulsion for a C-H bond (MnnRCHB) and Minimal Electrophilic Reactivity Index for a C atom (MERICA) can be more easily reduced. This QSPR approach can contribute to a better understanding of structural factors of the organic compounds that contribute to the E1/2, and can be useful in predicting the E1/2 of other compounds.
On the modification of methods of nuclear chronometry in astrophysics and geophysics
Authors: Olkhovsky Vladislav , Dolinska Marina 
Published: May 2009

Abstract
In practically all known methods of nuclear chronometry until now, research has usually taken into account the life-times of only the fundamental states of α-radioactive nuclei. But in the processes of nuclear synthesis in stars and under the influence of constant cosmic radiation on the surfaces of planets the excitations of the α-radioactive nuclei are still ongoing. Between these processes there are states with excited α-particles inside the parent nuclei leading to much smaller life-times. And inside the large masses of stellar, terrestrial and meteoric substances there are transitions between different internal conditions of radioactive nuclei that are accompanied by infinite chains of γ-radiations with subsequent γ-absorptions, further γ-radiations, etc. For a description of the α-decay evolution that accounts for such excited states and multiple γ-radiations and γ-absorptions inside stars, and under the influence of cosmic radiation on the Earth’s surface we present a quantum-mechanical approach, which is based on the generalized Krylov-Fock theorem. A few simple estimations are also presented. These approaches lead to the conclusion that the usual (non-corrected) “nuclear clocks” do really point not to realistic values but to the upper limits of the durations of α-decay in stellar and planet processes.
A hierarchy of Hamilton operators and entanglement
Authors: Steeb Willi-Hans , Hardy Yorick 
Published: May 2009

Abstract
We consider a hierarchy of Hamilton operators Ĥ
N in finite dimensional Hilbert spaces $$
\mathbb{C}^{2^N }
$$. We show that the eigenstates of Ĥ
N are fully entangled for N even. We also calculate the unitary operator U
N(t) = exp(—Ĥ
N
t/ħ) for the time evolution and show that unentangled states can be transformed into entangled states using this operator. We also investigate energy level crossing for this hierarchy of Hamilton operators.
Interfacial wave propagation due to an interfacial line source
Authors: Qazi Zahid , Rizvi Azhar 
Published: May 2009

Abstract
Interfacial wave propagation parallel to a dielectric interface has been studied by considering an electric current line source present at the interface. The first order asymptotic evaluation of field components shows a null of the electric field at the interface. An amplitude null represents an unstable structure in the phase map and a phase front discontinuity across the interface. Higher order asymptotic evaluation has been employed to gain further insight into this propagation problem. The results show that the wavefronts need not be discontinuous. The continuity of the phase fronts is preserved with the help of interesting and stable structures such as saddle points and center points in the phase map of the electric field in both half spaces.
A case of ichthyosiform sarcoidosis with unusual localization
Authors: Tekin Salim , Cayir Kerim , Bilici Mehmet , Şipal Sare , Atasoy Mustafa , Türkeli Mehmet 
Published: May 2009

AbstractSarcoidosis is a systemic granulomatous disease of unknown cause that commonly involves the lungs, lymph nodes, bones, liver, spleen, or skin. Cutaneous findings of sarcoidosis occur in 20% to 35% of patients with systemic disease. The recognition of cutaneous lesions is important, because it gives important clues to diagnosis and also allows for easy biopsy. We report a 71-year-old Turkish woman with erythematous lesions, which included widespread, erythematous macules of various sizes on the chest, abdomen, and back on both sides of her body. Fine white scales covered some of the lesions. Hepatomegaly and bilateral hilar lymphadenopathy were also observed. Biopsy specimens of the skin showed dermal, noncaseating, epitheloid granulomas. The diagnosis, based on correlation of the clinical presentation and histopathological findings, was ichthyosiform sarcoidosis with systemic involvement. The difference between our case and other cases of ichthyosiform sarcoidosis described in the literature is that ours involved only the trunk and not the extremities. We are presenting this case because it is an interesting and rare variant of ichthyosiform sarcoidosis.
Divisibity, iterated digit sums, primality tests
Authors: Ericksen Larry 
Published: May 2009

Abstract
The divisibility of numbers is obtained by iteration of the weighted sum of their integer digits. Then evaluation of the related congruences yields information about the primality of numbers in certain recursive sequences. From the row elements in generalized Delannoy triangles, we can verify the primality of any constellation of numbers. When a number set is not a prime constellation, we can identify factors of their composite numbers. The constellation primality test is proven in all generality, and examples are given for twin primes, prime triplets, and Sophie Germain primes.
Σn+1-invariant forms of higher degree
Authors: Sładek Andrzej 
Published: May 2009

Abstract
In [EGAWA, Y.—SUZUKI, H.: Automorphism groups of Σn+1-invariant trilinear forms, Hokkaido Math. J. 11, (1985), 39–47] are explored Σn+1-invariant symmetric trilinear forms and their automorphisms. In the paper we generalize their results to d-linear symmetric forms for any d ≥ 3.
Right triangles with algebraic sides and elliptic curves over number fields
Authors: Girondo E. , González-Diez G. , González-Jiménez E. , Steuding R. , Steuding J. 
Published: May 2009

Abstract
Given any positive integer n, we prove the existence of infinitely many right triangles with area n and side lengths in certain number fields. This generalizes the famous congruent number problem. The proof allows the explicit construction of these triangles; for this purpose we find for any positive integer n an explicit cubic number field ℚ(λ) (depending on n) and an explicit point P
λ of infinite order in the Mordell-Weil group of the elliptic curve Y
2 = X
3 − n
2
X over ℚ(λ).
A hypergeometric approach, via linear forms involving logarithms, to criteria for irrationality of Euler’s constant
Authors: Sondow Jonathan , Zlobin Sergey 
Published: May 2009

Abstract
Using an integral of a hypergeometric function, we give necessary and sufficient conditions for irrationality of Euler’s constant γ. The proof is by reduction to known irrationality criteria for γ involving a Beukers-type double integral. We show that the hypergeometric and double integrals are equal by evaluating them. To do this, we introduce a construction of linear forms in 1, γ, and logarithms from Nesterenko-type series of rational functions. In the Appendix, S. Zlobin gives a change-of-variables proof that the series and the double integral are equal.
Pseudo-randomness of van der Corput’s sequences
Authors: Blažeková O. 
Published: May 2009

Abstract
The aim of this paper is to find main terms of the star D
N* and extremal D
N discrepancies of the two dimensional sequence (x
n, x
n+1), n = 0, 1, 2, ..., N − 1, where x
n, n = 0, 1, 2, ..., is the van der Corput sequence. This give a quantitative form of a well-known result that van der Corput sequence is not pseudorandom.
On the distribution of reducible polynomials
Authors: Kuba Gerald 
Published: May 2009

Abstract
Let ℛn(t) denote the set of all reducible polynomials p(X) over ℤ with degree n ≥ 2 and height ≤ t. We determine the true order of magnitude of the cardinality |ℛn(t)| of the set ℛn(t) by showing that, as t → ∞, t
2 log t ≪ |ℛ2(t)| ≪ t
2 log t and t
n ≪ |ℛn(t)| ≪ t
n for every fixed n ≥ 3. Further, for 1 < n/2 < k < n fixed let ℛk,n(t) ⊂ ℛn(t) such that p(X) ∈ ℛk,n(t) if and only if p(X) has an irreducible factor in ℤ[X] of degree k. Then, as t → ∞, we always have t
k+1 ≪ |ℛk,n(t)| ≪ t
k+1 and hence |ℛn−1,n
(t)| ≫ |ℛn(t)| so that ℛn−1,n
(t) is the dominating subclass of ℛn(t) since we can show that |ℛn(t)∖ℛn−1,n
(t)| ≪ t
n−1(log t)2.On the contrary, if R
ns(t) is the total number of all polynomials in ℛn(t) which split completely into linear factors over ℤ, then t
2(log t)n−1 ≪ R
ns(t) ≪ t
2 (log t)n−1 (t → ∞) for every fixed n ≥ 2.
On the parity of the class number of the 7nth cyclotomic field
Authors: Ichimura Humio 
Published: May 2009

Abstract
For an odd prime number p and an integer n ≥ 0, let h
n be the class number of the p
n+1st cyclotomic field Q($$
\zeta _{p^{n + 1} }
$$). It is known that when p = 3 or 5, h
n is odd for all n ≥ 0. We prove that the same holds also when p = 7.
Evaluation of infinite series involving special products and their algebraic characterization
Authors: Genčev Marian 
Published: May 2009

Abstract
The aim of the paper is the investigation of special infinite series of the form $$
\sum\limits_{n = 0}^\infty {\left( {\frac{{\prod\limits_{s = 0}^{m_1 n} {(s + a)} \prod\limits_{s = 0}^{m_2 n} {(s + b)} }}
{{\prod\limits_{s = 0}^{(m_1 + m_2 )n + 1} {(s + a + b)} }}} \right)} ^c \cdot \frac{{P(n)}}
{{\theta ^n }} \cdot f_n (n)
$$ where (a, b, m
1, m
2, θ, c, P(n)) ∈ ℝ4 × ℂ × {±1} × [n] and $$
\{ f_n (n)\} _{n \in \mathbb{N}_0 }
$$ is a sequence of rational functions. A general summation method for the sum above in the case of the special choice of parameters a, b and f
n(n) is included. We find the 2m-tuple of rational numbers α
i, β
j (1 ≤ i ≤ m, 1 ≤ j ≤ m) for which iff and vice versa.
Scrambling non-uniform nets
Authors: Tezuka Shu 
Published: May 2009

Abstract
In this paper, we consider Owen’s scrambling of an (m−1, m, d)-net in base b which consists of d copies of a (0, m, 1)-net in base b, and derive an exact formula for the gain coefficients of these nets. This formula leads us to a necessary and sufficient condition for scrambled (m − 1, m, d)-nets to have smaller variance than simple Monte Carlo methods for the class of L
2 functions on [0, 1]d. Secondly, from the viewpoint of the Latin hypercube scrambling, we compare scrambled non-uniform nets with scrambled uniform nets. An important consequence is that in the case of base two, many more gain coefficients are equal to zero in scrambled (m − 1, m, d)-nets than in scrambled Sobol’ points for practical size of samples and dimensions.
Consensus among Physiotherapists in the United Kingdom on the Use of Normal Saline Instillation Prior to Endotracheal Suction: A Delphi Study
Authors: Roberts Fiona E. 
Published: May 2009

Purpose: To investigate whether physiotherapists consider normal saline instillation (NSI) useful before endotracheal suctioning and, if so, when.Methods: Sixty-eight respiratory physiotherapists recruited from the United Kingdom's Association of Chartered Physiotherapists in Respiratory Care agreed to participate in a Delphi study. Clinicians’ opinion of when NSI should be used was established and developed into statements. Level of agreement with each statement was collated through three rounds of a questionnaire. Clinicians’ experiences were also reported.Results: From the 52 responses to the third questionnaire, there was consensus that respiratory physiotherapists in the United Kingdom would use NSI when sputum retention is a problem, particularly when treatment options are limited (96%) and when sputum is obstructing the airway (92%). They agreed that non-bronchoscopic bronchoalveolar lavage can be used to resolve persistent atelectasis (70%). They would not use NSI for a test treatment during initial assessment without evidence of retained secretions (94%), when secretions are copious but can be cleared by alternative physiotherapy techniques (96%), to enhance a cough unless very strong evidence indicates retained secretions (81%), or to compensate for inadequate suction technique (90%).Conclusion: This study provides clinicians’ views about when NSI could be used.
Healthy Eating Champions Award For Elementary Schools
Authors: He Meizi , Callaghan Christine , Evans Anita , Mandich Gillian 
Published: May 2009

Purpose: The Healthy Eating Champions Award for Elementary Schools (HEC) is a public health initiative that recognizes and rewards schools for their outstanding commitment to the promotion of nutrition, for nutrition education, and for making healthy foods and beverages available. This process evaluation assessed HEC implementation, identified benefits and barriers, and solicited suggestions for program improvement. Methods: In-person interviews with principals or their designates from 28 HEC participating schools were conducted in fall 2006. Results: Participants had positive feelings about the HEC program and shared many success stories. Perceived program benefits included increased student awareness about healthy eating, more student involvement in healthy eating initiatives, the creation of opportunities for goal setting and spirit boosting, and improved hygiene practices. The challenge of getting parents and teachers involved and the significant financial needs of schools in low-income areas were identified as challenges. Conclusions: Participants view the HEC program as having a positive impact on the healthy eating environment in schools.
Determinants of Diet QualityAmong Canadian Adolescents
Authors: Storey Kate E. , Hanning Rhona M. , Lambraki Irene A. , Driezen Pete , Fraser Shawn N. , McCargar Linda J. 
Published: May 2009

Purpose: Dietary intakes and nutrition behaviours were examined among different diet quality groups of Canadian adolescents.Methods: This cross-sectional study included 2850 Alberta and Ontario adolescents aged 14 to 17, who completed a self-administered web-based survey that examined nutrient intakes andmeal behaviours (meal frequency andmeal consumption away from home).Results:Meanmacronutrient intakes were within Acceptable Macronutrient Distribution Ranges; however,micronutrient intakes andmedian food group intakes were below recommendations based on Canada's Food Guide to Healthy Eating (CFGHE). Overall diet quality indicated that 43%, 47%, and 10%of students had poor, average, and superior diet quality, respectively. Adolescents with lower diet quality had significantly different intakes of macronutrients and CFGHE-defined “other foods.” In terms of diet quality determinants, those with poor diet quality had higher frequencies of suboptimalmeal behaviours. Students with poor diet quality consumed breakfast and lunch less frequently than did those with average and superior diet quality.Conclusions: Canadian adolescents have low intakes of CFGHE-recommended foods and high intakes of “other foods.” Those with poor diet quality had suboptimal macronutrient intakes and increased meal skipping and meal consumption away from home. Adherence to CFGHE may promote optimal dietary intakes and improve nutritional behaviours.
Paint Your Plate: Effectiveness of a Point-of-purchase Display
Authors: Colapinto Cynthia K. , Malaviarachchi Darshaka 
Published: May 2009

Purpose: This study was conducted to determine consumer understanding and retention of nutrition information presented at grocery stores during the Paint Your Plate campaign via two approaches: interactive display events and brochure distribution. Methods: Data were collected at 17 grocery stores in northern Ontario. Eleven stores held interactive display events with public health staff, a display, resources, and food samples. Six stores only distributed brochures. A total of 688 participants completed a baseline questionnaire, and 432 consented to a three-month follow- up telephone call. Of these, 201 were randomly selected to participate. Results: Participants at interactive display events were six times more likely than participants receiving brochures to identify a serving size of fruit and vegetables (odds ratio [OR]=5.88; 95%confidence interval [CI]: 4.05, 8.54) and 23 timesmore likely to identify the recommended number of servings of fruit and vegetables (OR=22.67; 95%CI: 14.29, 35.98).However, at follow-up, there was no significant difference between type of event and the ability to answer correctly. Conclusions: Interactive displays increased immediate knowledge but failed to increase retention, a finding that suggests consistent presence of the message is needed to reinforce initial understanding and retention. More emphasis should be placed on directing funding toward increasing the frequency and duration of promotional efforts.
Dietary habits and health beliefsOf Chinese Canadians
Authors: Kwok Stephanie , Mann Linda , Wong Kwan , Blum Ilya 
Published: May 2009

Purpose: The relationships among dietary behaviours, traditional health beliefs (THB), and demographic characteristics of Chinese Canadians living in Toronto were examined, as were their primary sources of nutrition information.Methods: Through the use of probability sampling, 106 adult subjects who originated fromChina, Hong Kong, or Taiwan were recruited fromfive Chinese community organizations. A telephone interview, employing a tested questionnaire, was conducted in Cantonese orMandarin. All data were analyzed with MS Excel and SPSS statistical software.Results: Dietary acculturation is gradual and individual. Participants reported regular intakes of fruits and vegetables and fat-reducing behaviours. Most used both Chinese and Western cooking methods. Practices based on traditional Chinese health beliefs (THB), such as balancing yin and yang foods to promote health, were prevalent. Participants were grouped as THB-strong, THB-moderate, or THB-weak, on the basis of their health belief scores. Various significant relationships among the variables were identified. Chinese media, friends, and family were the primary sources of nutrition information; dietitians were identified by only 12%.Conclusions: This is the first study to apply a THB grouping for Chinese Canadians. Results will provide an important basis for nutrition interventions to encourage immigrants to make healthy food choices, using both traditional and Western foods.
Reasons for Non-Return toA Pediatric Weight Management Program
Authors: Kitscha Catherine E. , Brunet Kim , Farmer Anna , Mager Diana R. 
Published: May 2009

Purpose: Obesity in childhood has become a major public health concern because of increasing rates of overweight and obesity. To address this epidemic, effective dietetic interventions must be developed. We examined parent/caregiver and/or patient reasons for not returning for follow-up clinical care in the Alberta Health Services, Edmonton Area's Nutrition Services Pediatric Weight Management Program (NS PWMP) in Edmonton, Alberta.Methods: A qualitative telephone survey was developed to identify reasons for non-return to the NS PWMP. Face validity was evaluated by five pediatric registered dietitians (RDs).Results: The survey was administered to parents/caregivers of children or adolescents aged 2.5 to 14.2 years (n=21) who attended fewer than two appointments in the NS PWMP. The major reasons for non-return included physical barriers (scheduling, parking, location), organizational barriers (clinic environment), and program educational content (type of educational tools, the focus of lifestyle education on the individual rather than the family, physical activity interventions, and appropriateness of information for the parent or child).Conclusions: Development and delivery of effective dietetic interventions for children and adolescents at risk of overweight and obesity may be achieved by emphasizing skill building within the child and the family. Analysis of child and family feedback on clinical RD services is critical to optimization of care in a pediatric weight management program.