bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Opposite of Sex? Adolescents’ Thoughts About Abstinence and Sex, and Their Sexual Behavior
Authors: Masters N. Tatiana , Beadnell Blair A. , Morrison Diane M. , Hoppe Marilyn J. , Gillmore Mary Rogers 
Published: June 2008

CONTEXT:  Little research has explored how teenagers think about abstinence and how it functions in their lives. These questions are particularly salient in light of widespread funding of abstinence‐only programs in the United States. METHODS:  Data on attitudes and intentions related to abstinence and sex were collected from 365 adolescents aged 12–15 who participated in an HIV risk reduction program in Seattle in 2001–2003. Logistic regression analyses assessed associations between these cognitions, as measured six months after the program, and teenagers’ likelihood of having vaginal or anal sex in the subsequent six months. RESULTS:  Adolescents who had positive attitudes and intentions about abstinence had a reduced likelihood of subsequently engaging in sex (odds ratio, 0.6 for each), whereas those with positive attitudes and intentions about having sex had an elevated likelihood of engaging in sex (2.2 and 3.5, respectively). A regression model including only sex cognitions accounted for substantially more variation in sexual activity than did one including only abstinence cognitions (15–26% vs. 6–8%). Significant interaction effects were also seen: Among teenagers with low levels of sex intention, greater abstinence intention had little relationship to the predicted probability of having sex, but among teenagers with high levels of sex intention, greater abstinence intention was associated with increases in the predicted probability of having sex. CONCLUSIONS:  Youth do not consider abstinence and sexual activity opposing constructs, and solely instilling positive abstinence attitudes and intentions in youth may not have robust effects in preventing sexual activity.
Simple inductive limit C*-algebras: Spectra and approximations by interval algebras
Authors: Li Liangqing 
Published: June 2008

Abstract
Suppose that a simple C*-algebra A can be written as an inductive limit of , where Xn,i are finite CW complexes with uniformly bounded dimensions. Such inductive limit C*-algebras are called AH algebras.
In this paper, we will prove that for any n and ε > 0, there exists a homomorphism ψn,m: An → Am, which factors through an interval algebra , such that the spectra of ψn,m and the spectra of φn,m can be paired within ε provided that m is large enough. This result is essential for the classification of such simple C*-algebras.
Cerebral Malaria in Children Is Associated With Long-term Cognitive Impairment
Authors: John Chandy C. , Bangirana Paul , Byarugaba Justus , Opoka Robert O. , Idro Richard , Jurek Anne M. , Wu Baolin , Boivin Michael J. 
Published: June 2008

OBJECTIVE. Cerebral malaria affects &gt;785000 African children every year. We previously documented an increased frequency of cognitive impairment in children with cerebral malaria 6 months after their initial malaria episode. This study was conducted to determine the long-term effects of cerebral malaria on the cognitive function of these children.
METHODS. Children who were 5 to 12 years of age and presented to Mulago Hospital, Kampala, Uganda, with cerebral malaria (n = 44) or uncomplicated malaria (n = 54), along with healthy, asymptomatic community children (n = 89), were enrolled in a prospective cohort study of cognition. Cognitive testing was performed at enrollment and 2 years later. The primary outcome was presence of a deficit in ≥1 of 3 cognitive areas tested.
RESULTS. At 2-year follow-up testing, 26.3% of children with cerebral malaria and 12.5% with uncomplicated malaria had cognitive deficits in ≥1 area, as compared with 7.6% of community children. Deficits in children with cerebral malaria were primarily in the area of attention (cerebral malaria, 18.4%, vs community children, 2.5%). After adjustment for age, gender, nutrition, home environment, and school level, children with cerebral malaria had a 3.67-fold increased risk for a cognitive deficit compared with community children. Cognitive impairment at 2-year follow-up was associated with hyporeflexia on admission and neurologic deficits 3 months after discharge.
CONCLUSIONS. Cerebral malaria is associated with long-term cognitive impairments in 1 of 4 child survivors. Future studies should investigate the mechanisms involved so as to develop interventions aimed at prevention and rehabilitation.
Peptides Adsorbed on Hydrophobic Surfaces—A Sum Frequency Generation Vibrational Spectroscopy and Modeling Study
Authors: York Roger L. , Browne William K. , Geissler Phillip L. , Somorjai Gabor A. 
Published: June 2008

AbstractSum frequency generation (SFG) vibrational spectroscopy has been used to characterize the interfacial structure of a series of model peptides at the hydrophobic polystyrene‐buffer interface. The peptides contain two types of amino acids, one hydrophobic (X) and one hydrophilic (Y). Their sequences are Ac‐XYYXXYXXYYXXYX‐NH2 (XY14) and Ac‐XYXYXYX‐NH2 (XY7), respectively, where the X and Y combinations are: leucine (L) and lysine (K); alanine (A) and lysine (K); alanine (A) and arginine (R); and phenylalanine (F) and arginine (R), respectively. One additional peptide was synthesized and characterized, Ac‐LKKLLKL‐NH2, referred to as LK7 α. The XY14 peptides showed SFG spectra that were characteristic of the hydrophobic (X) amino acid of the peptide. Comparison with the 7‐amino acid peptides shows that the molecular orientation of alanine is more sensitive to changes in sequence and chain length than leucine or phenylalanine. The hydrophilic amino acids are not observed in the SFG spectra of these peptides at the hydrophobic polystyrene interface (with the possible exception of the AR7 peptide), suggesting the hydrophilic amino acids studied here have a random orientation at this interface. The results of these studies are put into the context of recent SFG studies of proteins adsorbed onto hydrophobic surfaces. Furthermore, our approach to theoretical understanding of interfacial peptide structure is outlined. The results of a molecular dynamics simulation of the LK14 peptide on a hydrophobic interface are presented and discussed.
A Continuous Spawning Method for Nonadiabatic Dynamics and Validation for the Zero‐Temperature Spin‐Boson Problem
Authors: Ben‐Nun Michal , Martínez Todd J. 
Published: June 2008

AbstractA four‐dimensional spin‐boson model is used to study the convergence and accuracy of the full multiple spawning (FMS) method using two spawning algorithms. The original spawning algorithm, based on the idea of effective non‐adiabatic coupling, is expected to be optimal when the coupling between electronic states is either spatially or temporally localized. The new “continuous spawning” algorithm ensures that at all times there is a (user defined) minimal overlap between a basis function traveling on one electronic state and one (or more) basis functions traveling on the other electronic state. The algorithm is expected to be numerically efficient when the electronic states are coupled by a constant, position‐independent term, as is the case in spin‐boson models. The fast convergence of the algorithm is demonstrated by direct comparison to numerically converged results obtained using the multi‐configuration time‐dependent Hartree method. The results of the FMS dynamics are also compared to the more classical surface‐hopping and Ehrenfest methods. The surface‐hopping and Ehrenfest methods are shown to be sensitive to the particular method used to choose the trajectory initial conditions (quasi‐classical vs. Wigner), while the FMS method is not very sensitive to this choice.
Electron capturing by DNA
Authors: Ray Supratim G. , Daube Shirley S. , Cohen Hagai , Naaman Ron 
Published: June 2008

AbstractMany of the mutagenic or lethal effects of ionization radiation can be attributed to damage caused to the DNA by low‐energy electrons. In order to gain insight on the parameters affecting this process, we measured the low‐energy electron (<2 eV) transmission yield through self‐assembled monolayers of short DNA‐oligomers. The electrons that are not transmitted are captured by the layer. Hence, the transmission reflects the capturing efficiency of the electrons by the layer. The dependence of the capturing probability on the base sequence was studied as well as the state of the captured electrons. In addition, two‐photon photoelectron (TPPE) spectroscopy studies were performed that established the binding energy of electrons on the DNA.We found that the capturing probability scales with the number of G bases in the single‐stranded oligomers and depends on their clustering level. Using TPPE spectroscopy, we found that once captured, the electrons do not reside on the bases. Rather, the state of the captured electrons is insensitive to the oligomer's sequence. A model is proposed for the special role of guanine, based on its low oxidation potential.Double‐stranded DNA does not capture electrons as efficiently as single‐stranded oligomers; however, once captured, the electrons are more strongly bound than to the single strands.
Influences of electroosmotic flows in nanopillar chips on DNA separation: Experimental results and numerical simulations
Authors: Kaji Noritada , Oki Akio , Ogawa Ryo , Takamura Yuzuru , Nishimoto Takahiro , Nakanishi Hiroaki , Horiike Yasuhiro , Tokeshi Manabu , Baba Yoshinobu 
Published: June 2008

AbstractThe various potential factors affecting the performance of nanopillar chips on DNA separation were investigated from the viewpoints of both numerical calculations and actual experiments. To yield higher performance and replace the conventional DNA separation techniques such as microchip electrophoresis, the phenomenon specific to the nanopillar chips should be deeply understood. In this paper, although various factors affecting the performance of the nanopillar chips are considered, we focused on the effect of electroosmotic flow, which is particularly noticeable in quartz‐made nanopillar chips. High‐resolution separation of DNA was realized when an electroosmotic flow was suppressed by simply using a higher concentration of buffer, but DNA separation failed in the presence of an electroosmotic flow. It was confirmed from the numerical simulations and the direct observations that the deformation of DNA band during the injection process was induced by electroosmotic flow and consequently led to a poor resolution.
Fluorescence correlation spectroscopy at 100 nM concentrations using near‐field scanning optical microscopic (NSOM) geometries and highly diffracting force sensing fiber probes
Authors: Lewis Aaron , Kuttner Yosef Yehuda , Dekhter Rimma , Polhan Mila 
Published: June 2008

AbstractA tapered cantilevered optical fiber probe is introduced for fluorescence correlation spectroscopy (FCS). The probe has an aperture that is coated with metal and its dimension can be very well defined. Its design is based on cantilevered near‐field optical fiber probes that allow for on‐line atomic force feedback. This permits unprecedented stability in FCS measurements. Even such probes that have large diameters are below the cutoff wavelength of light propagation in optical fibers. Such large diameter probes produce bright spots of light that are highly diffracting. Therefore, only the fluence of light very close to the surface of the glass probe aperture is sufficient to exhibit a high probability of fluorescence excitation. From the results presented in this paper the z extent of such probes seems comparable to what can be obtained from prism‐based evanescent wave methods, but with much more flexibility and including force sensing capability. In agreement with theoretical results on prism evanescent field‐based excitation, it is shown that even with large xy dimensions for the fiber probes in this paper, fluorescence correlation spectra from 100 nM fluorophore concentrations can be recorded. This is 10 times larger than the concentrations generally required for conventional confocal FCS. The results suggest that such an approach has considerable potential for applications of FCS in membrane, near‐membrane, solution, and even within‐cell environments. The latter is achieved through atomic force feedback controlled penetration of tapered cantilevered metal‐coated glass fibers into cells, and this is also reported in this paper.
Activated sludge process monitoring through in situ near-infrared spectral analysis
Authors: Dias A. M. A. , Moita I. , Alves M. M. , Ferreira E. C. , Páscoa R. , Lopes J. A. 
Published: June 2008

The application of near infrared (NIR) spectroscopy for industrial process monitoring is achieving increasing importance over the last twenty years. In fact, the real time monitoring capacity of NIR spectroscopy is a very important feature for process monitoring, prediction and control as it allows a fast evaluation of the state of the process. However, the application of NIR spectroscopy in wastewater treatment processes is still to be explored. Although some applications of the technique for wastewater monitoring have been reported in the literature, there is still a need for more investigation related with applications, limitations and advantages of the technique when compared with other methods.
An activated sludge reactor for aerobic treatment of a complex medium was monitored in situ with a NIR transflectance probe and traditional chemical parameters analysed off-line. NIR spectrophotometric data measured at the feed, reactor and settler were coupled to principal component analysis (PCA) to infer about the ability of this monitoring system to detect changes in the feed influent. The analysis of the score plots resulting from PCA permitted to identify the moments at which the perturbations occurred and to follow the consequent instability induced in the reactor till the day where the system is recuperated. The promising results obtained, suggest the interest in more detailed studies on the feasibility of NIR spectroscopy as an alternative method for monitoring and control of wastewater treatment processes.
Visual identification of underwater objects using a ROV-type vehicle: "Graf Zeppelin" wreck investigation
Authors: Olejnik Commander 
Published: June 2008

Visual identification of underwater objects using a ROV-type vehicle: "Graf Zeppelin" wreck investigation
The article presents a method of visual identification of underwater objects using a remotely controlled underwater ROV-type vehicle. The method was developed in the Department of Diving Technology and Underwater Activities, Polish Naval Academy, and was positively verified when identifying wrecks of such vessels as "General von Steuben", "Fryderyk Engels" and "Graf Zeppelin". The article gives a description of the method, illustrated by samples of its use for investigating the wreck of "Graf Zeppelin"
Classification of the underwater diving equipment
Authors: Kłos Ryszard 
Published: June 2008

Classification of the underwater diving equipment
In this paper was presented, innovative in preparation of the diving apparatuses classification method, depend on three criteria: the kind of the breathing gas, the operational depth range of the diving apparatus, and the principle of operation. The breathing gas used is the most important criterion. The other basic classification criteria follow from the first one; therefore it should be treated as the one criterion. Such approach to the problem has never been presented before, however it seems to be correct method of the diving apparatuses division.
Neutron Bragg Diffraction on a Bent Silicon Single Crystal Excited by Ultrasound
Authors: Raitman E. , Gavrilov V. , Brezgunov M. , Mjasiscev D. 
Published: June 2008

Neutron Bragg Diffraction on a Bent Silicon Single Crystal Excited by UltrasoundThe neutron Bragg diffraction on a bent silicon monocrystal excited by ultrasound was investigated. It is shown that for perfect crystal the relative diffraction intensity is proportional to the acoustic wave amplitudew.The calibration parameters between the generator voltage and acoustic wave amplitude were derived assumingw= (2.3±0.3)·10-2Å/V. To explain the results, a modified Penning—Polder—Kato model was applied. In a bent crystal, owing to ultrasound, transitions between the sheets of a dispersion surface take place. This leads to various manifestations of the behaviour of the integral scattering intensity, which drastically differs from the case of a perfect crystal. The observed effects may be used for creating new types of neutron monochromators and choppers governed by the ultrasound wave amplitude as well as by the length and bending radius of the crystal.
Development between nuance and neo-liberalism
Authors: Büscher Bram 
Published: June 2008

David Mosse, Cultivating development: An ethnography of aid policy and practice. London: Pluto Press, 2005, 315 pp., 0-7453-1798-7.Tania M. Li, The will to improve: Governmentality, development, and the practice of politics. Dur- ham, NC: Duke University Press, 2007, 374 pp., 0-8223-4027-0 (paperback).Richard Sandbrook, Marc Edelman, Patrick Heller and Judith Teichman, Social democracy in the global periphery: Origins, challenges, prospects. Cambridge: Cambridge University Press, 2007, 289 pp., 0-521-68687-7 (paperback).
Erythropoiesis stimulating agents are associated with reduced survival in patients with multiple myeloma
Authors: Katodritou Eirini , Verrou Evgenia , Hadjiaggelidou Christina , Gastari Vassiliki , Laschos Konstantinos , Kontovinis Loukas , Kapetanos Dimitrios , Constantinou Nikos , Terpos Evangelos , Zervas Konstantinos 
Published: June 2008

AbstractThe impact of erythropoiesis‐stimulating agent (ESA) on cancer patients' survival has recently become a matter of extensive discussion. Studies in solid tumors demonstrated that ESA adversely affects survival. This issue has not been sufficiently studied in patients with multiple myeloma. In this study, which included 323 multiple myeloma patients followed in our Institution between 1988 and 2007, we demonstrated by using a proportional hazards model including multiple covariates (age, LDH, Hb, platelets, serum creatinine, ISS score, β2 microglobulin, and ESA administration) that ESA administration is associated with reduced survival (hazards ratio: 1.88, 95% CI: 1.28–2.77). Anemia, which is considered a predictor for survival, platelets, serum creatinine, ISS score, and LDH, were not significant, whereas, age and β2 microglobulin confirmed their predicting value in the multivariate analysis. With a median follow‐up of 31 months (range 1–238), the median survival of patients in the ESA group was 31 months (95% CI: 25–37), whereas in the group without ESA administration it was 67 months (95% CI: 55–79) (P < 0.001). The median progression‐free survival for patients in the ESA group was 14 months (95% CI: 12–16), and for the group without ESA it was 30 months (95% CI: 24–36) (P < 0.001). These results indicate that ESA may have a detrimental impact on MM patients' outcomes and, thus, in this context, they should be used with rigorous criteria. © 2008 Wiley‐Liss, Inc. Am. J. Hematol., 2008.
Population growth and mass mortality of an estuarine fish, Acanthopagrus butcheri, unlawfully introduced into an inland lake
Authors: Smith Kimberley , Norriss Jeff , Brown Joshua 
Published: June 2008

Abstract
In 2006, two periods of hypoxia resulted in the death of approximately 35 tonnes of black bream (Acanthopagrus butcheri) in Lake Indoon, a small inland lake in Western Australia.
Acanthopagrus butcheri was the first fish species to be recorded in this lake, along with the mosquitofish (Gambusia holbrooki) which was also observed during sampling in 2006. Acanthopagrus butcheri appears to have been introduced to Lake Indoon between 1998 and 2003 and formed a self‐sustaining population. It is believed to have been deliberately introduced for the purpose of creating a recreational fishery, despite the existence of substantial penalties for illegal translocation of fish in Western Australia.
Recent human‐induced environmental changes, including rising groundwater and salinization, have probably aided the establishment of both species in Lake Indoon. The importance of salinity to recruitment success by A. butcheri was indicated by the presence of only two age classes in 2006, with estimated recruitment dates coinciding with the years of highest recorded salinity in the lake.
The ‘fish kills’ provided an opportunity to examine aspects of A. butcheri biology in a relatively low salinity environment which is atypical for this estuarine species. In particular, the recruitment period in Lake Indoon was delayed until autumn/winter, rather than spring/summer as seen in other populations. Biological responses in Lake Indoon have implications for natural populations living in estuaries with modified salinity regimes.
The ecological, social and economic impacts potentially arising from the introduction of fish to Lake Indoon, which is an important migratory bird habitat and a recreational amenity for local residents and tourists, illustrate the complexities of fish translocation and the need for rigorous assessment before stocking to identify potential costs and benefits.
Copyright © 2008 John Wiley & Sons, Ltd.
Gradient climbing in formation via extremum seeking and passivity‐based coordination rules
Authors: Bıyık Emrah , Arcak Murat 
Published: June 2008

AbstractWe consider a gradient climbing problem where the objective is to steer a group of vehicles to the extrema of an unknown scalar field distribution while keeping a prescribed formation. We address this problem by developing a scheme in which the leader performs extremum seeking for the minima or maxima of the field, and other vehicles follow according to passivity‐based coordination rules. The extremum‐seeking approach generates approximate gradients of the field locally by “dithering” sensor positions. We show that if there is sufficient time‐scale separation between the fast dither and slow gradient motions of the leader vehicle, the followers only respond to the gradient motion, and filter out the dither component. Copyright © 2008 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Distributed dynamic control for leaderless multi‐agent consensus with star‐like topology
Authors: Hu Jiangping , Hong Yiguang , Feng Gang 
Published: June 2008

AbstractIn this paper, we consider a consensus problem of a group of mobile agents interconnected by a star‐like topology. Not all the state variables of the agent in the center of the group are available for its neighbors. A distributed controller together with a local state‐estimation rule is given for each agent who has to estimate the unmeasurable velocity. Then, with help of virtual equivalent agents, we prove that, with the proposed control scheme, the group of agents can reach its consensus. Copyright © 2008 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
The χ‐consensus problem of high‐order multi‐agent systems with fixed and switching topologies
Authors: Jiang Fangcui , Xie Guangming , Wang Long , Chen Xiaojie 
Published: June 2008

AbstractIn this paper, the χ‐consensus problems for multiple high‐order dynamical agents within fixed and switching topologies are investigated. A linear protocol is established to globally asymptotically solve χ‐consensus problem for such systems. Moreover, the decision value may be determined by the feedback gains and the initial states of agents. Based on spectral analysis of system's coefficient matrix some conditions are presented for solving the consensus problem with fixed topologies. In the switching topologies case solving the consensus problem is proved by the asymptotical stability analysis regarding to the origin of its disagreement dynamics through Lyapunov approach. Copyright © 2008 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society