bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaporation estimation on Lake Titicaca: a synthesis review and modelling
Authors: Delclaux François , Coudrain Anne , Condom Thomas 
Published: January 2007

AbstractThe aim of this study was to validate evaporation models that can be used for palaeo‐reconstructions of large lake water levels. Lake Titicaca, located in a high‐altitude semi‐arid tropical area in the northern Andean Altiplano, was the object of this case study. As annual evaporation is about 90% of lake output, the lake water balance depends heavily on the yearly and monthly evaporation flux. At the interannual scale, evaporation estimation presents great variability, ranging from 1350 to 1900 mm year−1. It has been found that evaporation is closely related to lake rainfall by a decreasing relationship integrating the implicit effect of nebulosity and humidity. At the seasonal scale, two monthly evaporation data sets were used: pan observations and estimations derived from the lake energy budget. Comparison between these data sets shows that (i) there is one maximum per year for pan evaporation and two maxima per year for lake evaporation, and (ii) pan evaporation is greater than lake evaporation by about 100 mm year−1. These differences, mainly due to a water depth scale factor, have been simulated with a simple thermal model θw(h, t) of a free‐surface water column. This shows that pan evaporation (h = 0·20 m) is strongly correlated with direct solar radiation, whereas the additional maximum of lake evaporation (h = 40 m) is related to the heat restitution towards the atmosphere from the water body at the end of summer. Finally, five monthly evaporation models were tested in order to obtain the optimal efficiency/complexity ratio. When the forcing variables are limited to those that are most readily available in the past, i.e. air temperature and solar radiation, the best results are obtained with the radiative Abtew model (r = 0·70) and with the Makkink radiative/air temperature model (r = 0·67). Copyright © 2007 John Wiley & Sons, Ltd.
Three‐dimensional laser micrometry characterization of surface wear in total hip arthroplasty
Authors: Kohm Andrew , Gaumer Jeremy , Ravula Vishnu , Urban Robert , Gilbertson Les , Bos Gary , Dey Tamal , Nelson Laura , Dyce Jonathan , Lannutti John 
Published: January 2007

AbstractEven after decades of clinical use, our ability to quantify wear across total hip replacement implant surfaces is largely limited to single value measurements. The influence of patient factors on wear remains enigmatic. This pilot study for the development of three‐dimensional laser micrometry (3DLM) introduces an easy, accurate means of ‘mapping’ and quantifying material removal. A three‐dimensional laser micrometer was constructed using a laser micrometer having an accuracy of 0.5 μm. A 3D surface map is triangulated from a point cloud consisting of ∼140,000 individual points. Comparison to a reference sphere determines radial wear over the entire surface. 3DLM was able to map and quantify fine scale surface features. Even for zirconia on relatively soft ultra‐high molecular weight polyethylene, this technique maps the contributions of localized wear at the macroscopic level. The 0.5 μm (or greater) accuracy of these lasers allows us to image surfaces with a high degree of confidence. This analysis lends itself well to automation, and we anticipate that this advance will prove valuable in establishing that each head and cup combination emerging from a given clinical environment has unique wear patterns as observed in this trial data set. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007
Molecular epidemiological study of hepatitis B virus infection in two different ethnic populations from the Solomon Islands
Authors: Utsumi Takako , Yano Yoshihiko , Truong Bui Xuan , Tanaka Yasuhito , Mizokami Masashi , Seo Yasushi , Kasuga Masato , Kawabata Masato , Hayashi Yoshitake 
Published: January 2007

AbstractThe Solomon Islands is a multi‐ethnic nation with a high rate of hepatitis B virus (HBV) infection. The prevalence relative to ethnicity was examined in relation to HBV infection, genotypes, and mutations. Asymptomatic populations (n = 564, 308 Melanesian and 118 Micronesian) from the Western Province were enrolled. Positive samples for Hepatitis B surface antigen (HBsAg) were examined for serological status, genotyping, viral load, and mutations of the basic core promoter (BCP) and pre‐core (Pre‐C) regions. The positive rate for HBsAg was 21.5%. The major Melanesian genotype was C (HBV/C), whereas the major Micronesian genotype was D (HBV/D). The prevalence of Hepatitis B e antigen (HBeAg) in serum was lower in carriers of HBV/D than of HBV/C. While the prevalence of the BCP mutation (T1762A1764) tended to be higher in HBV/C, that of the Pre‐C mutation (T1846) was significantly higher in HBV/D (P < 0.0001). Genetic distance and phylogenetic analyses based on complete genome sequences were also carried out for two strains of HBV/C and two strains of HBV/D, and the findings were compared with those in the DDBJ/EMBL/GenBank database. The full‐length sequence revealed that strains from the Solomon Islands were classified into subgenotype C3 (HBV/C3) and D4 (HBV/D4), and that the HBV/D strains were related closely to those from Papua New Guinea. HBV infection in the Solomon Islands is hyperendemic, and the genotype is ethnicity‐specific. HBeAg appears to clear from the serum in young adulthood in HBV/D infection, which may be influenced by genotype‐dependent features in relation to viral mutations. J. Med. Virol. 79:229–235, 2007. © 2007 Wiley‐Liss, Inc.
Long‐lasting effects of elevated neonatal leptin on rat hippocampal function, synaptic proteins and NMDA receptor subunits
Authors: Walker Claire‐Dominique , Long Hong , Williams Sylvain , Richard Denis 
Published: January 2007

AbstractThe high circulating levels of leptin in neonatal rodents do not seem to be regulating energy balance at this age, but rather may play an important role for brain development. We tested the hypothesis that high neonatal leptin levels modify hippocampal function and production of synaptic proteins with possible long‐term consequences on long‐term potentiation (LTP) in adulthood. We first showed that in postnatal day (PND) 10 neonates, acute leptin treatment functionally activated leptin receptors (ObR) in the CA1 and DG regions of the hippocampus through the induction of phosphoERK1/2, but not phosphoSTAT3 protein although both phospho‐proteins were induced in the arcuate nucleus. We next examined whether chronic leptin administration (3 mg/kg BW, intraperitoneally) during the first 2 weeks of life (postnatal day, PND 2–14) produces a functional signal in the hippocampus that alters the expression of NMDA receptor subunits (NR1, NR2A, NR2B), synaptic proteins and LTP in the short and long‐term. In PND 10 as in adults (PND 70) rats, chronic leptin treatment increased NR1 expression in the hippocampus while reducing NR2B protein levels. Elevated hippocampal concentrations of synapsin2A and synaptophysin were detected during leptin treatment on PND 10 suggesting increased neurotransmitter release. In adults, only SNAP‐25 expression was increased after neonatal leptin treatment. LTP was reduced dramatically by leptin treatment in preweaning rats although the changes did not persist until adulthood. Elevated exposure to leptin during a critical period of neonatal hippocampal development might serve to enhance NMDA‐dependent functions other than LTP and have important effects on synaptogenesis and neurotransmitter release. © 2007 Wiley‐Liss, Inc.
Functional Polymer‐Bioconjugates as Molecular LEGO® Bricks
Authors: Börner Hans G. 
Published: January 2007

AbstractThe controlled integration of sequence‐defined oligopeptides into synthetic polymers leads to peptide‐polymer conjugates with precisely defined, multifunctional peptide segments. These bioconjugates allow for the direct realization of bio‐inspired polymer science. Peptides combine self‐assembly properties with the potential to actively interact with biological systems. Hence conjugates can be exploited to program microstructure formation processes in polymeric materials by controlling secondary interactions between the peptide segments. Moreover, the programmable functionalities of the peptides can be used to tune specific interactions, e.g., between drugs and polymeric drug carriers or between inorganic crystal surfaces and polymeric crystal‐growth modifiers.magnified image
Exact expected values of variance estimators for simulation
Authors: Aktaran‐Kalaycı Tûba , Alexopoulos Christos , Argon Nilay Tanık , Goldsman David , Wilson James R. 
Published: January 2007

AbstractWe formulate exact expressions for the expected values of selected estimators of the variance parameter (that is, the sum of covariances at all lags) of a steady‐state simulation output process. Given in terms of the autocovariance function of the process, these expressions are derived for variance estimators based on the simulation analysis methods of nonoverlapping batch means, overlapping batch means, and standardized time series. Comparing estimator performance in a first‐order autoregressive process and the M/M/1 queue‐waiting‐time process, we find that certain standardized time series estimators outperform their competitors as the sample size becomes large. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007
Working with Arab American families: Culturally competent practice for school psychologists
Authors: Haboush Karen L. 
Published: January 2007

AbstractIndividuals of Arab descent residing within the United States currently number between 1.2 million and 3.9 million. These families are characterized by considerable diversity depending upon their nationality, religion, and extent of acculturation to both Western and Arab cultures. More recently, Arab families have immigrated to the United States in response to traumatic events, such as war, a situation that has complicated their subsequent adjustment and acculturation to life in the United States. The growth in the Arab American population suggests that school psychologists are increasingly likely to work with their children and families. However, despite the National Association of School Psychologists (NASP; 2000) and American Psychological Association (APA; 2002) ethical guidelines requiring culturally competent practice, little has been written to guide the school psychologist's work with this population. This article draws on the available literature on Arab cultural values and acculturation to enhance culturally sensitive school psychology practice at the individual and systems levels. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 183–198, 2007.
Learning from examples in unstructured, outdoor environments
Authors: Sun J. , Mehta T. , Wooden D. , Powers M. , Rehg J. , Balch T. , Egerstedt M. 
Published: January 2007

AbstractIn this paper, we present a multi‐pronged approach to the “Learning from Example” problem. In particular, we present a framework for integrating learning into a standard, hybrid navigation strategy, composed of both plan‐based and reactive controllers. Based on the classification of colors and textures as either good or bad, a global map is populated with estimates of preferability in conjunction with the standard obstacle information. Moreover, individual feedback mappings from learned features to learned control actions are introduced as additional behaviors in the behavioral suite. A number of real‐world experiments are discussed that illustrate the viability of the proposed method. © 2007 Wiley Periodicals, Inc.
Towards learned traversability for robot navigation: From underfoot to the far field
Authors: Howard Andrew , Turmon Michael , Matthies Larry , Tang Benyang , Angelova Anelia , Mjolsness Eric 
Published: January 2007

AbstractAutonomous off‐road navigation of robotic ground vehicles has important applications on Earth and in space exploration. Progress in this domain has been retarded by the limited lookahead range of three‐dimensional (3D) sensors and by the difficulty of heuristically programming systems to understand the traversability of the wide variety of terrain they can encounter. Enabling robots to learn from experience may alleviate both of these problems. We define two paradigms for this, learning from 3D geometry and learning from proprioception, and describe initial instantiations of them as developed under DARPA and NASA programs. Field test results show promise for learning traversability of vegetated terrain and learning to extend the lookahead range of the vision system. © 2007 Wiley Periodicals, Inc.
Photon‐induced field desorption of NO from Rh
Authors: Drachsel W. , Teutsch Th. 
Published: January 2007

AbstractThe effect of an electric field on the NO photo‐desorption from Rh was investigated using a pulsed laser atom probe. Experiments were carried out at 78 K by irradiating a [111] oriented Rh field‐emitter tip and a Rh single crystal of 1.4 mm diameter at 6.4 eV and at 3.2 eV photon energy. The energies and masses of the emitted ions were evaluated from time‐of‐flight (ToF) measurements. For 6.4 eV irradiation of the Rh tip, a quadratic yield dependence on the laser fluence has been observed for NO. This is interpreted as a two‐photon ionization of field‐adsorbed NO; this is supported by the same behavior of O2 and Xe but at a comparatively lower yield. In cases where the ionization energy of the probed species (Ar, N2, CO) is higher than 12.8 eV no such effect is observed. Laser irradiation with 2.3 eV photons initiates thermally assisted field desorption of the species at a comparatively higher fluence. Ion energy analysis suggests re‐neutralization of NO+ in the forbidden zone, but the translational energy gained appears to be sufficient to overcome the desorption barrier and field ionizion at the critical distance becomes probable. At low laser fluence a weak linear photo‐desorption process has been detected, presumably caused by substrate‐mediated electronic excitation as a first step. In this model, the photo‐desorbed NO will subsequently be field‐ionized, and accelerated away by the field. For the Rh single crystal, NO photo‐desorption, with two‐photon ionization in a second step, is deduced as the most probable mechanism. Copyright © 2007 John Wiley & Sons, Ltd.
Field ion microscopy and beyond in some aspects of surface and nanoscience applications
Authors: Tsong Tien T. 
Published: January 2007

AbstractTwo of the most important aspects of atomic resolution microscopy are the atomic resolution imaging of the sample and the nondestructive chemical analysis of preselected sample atoms. Field ion microscopy (FIM) is the first microscopy to achieve atomic image resolution, whereas the atom‐probe FIM is the first one to achieve single‐atom chemical analysis of preselected sample atoms, though, unfortunately, it is destructive. As microscopy progresses, now both electron microscope and scanning probe microscope have achieved atomic image resolution. STM may one day be able to do nondestructive chemical analysis of single sample atoms using thermally stable and chemically inert single‐atom sharp tip for the measurement of the electronic density of states of these atoms. Here, I will discuss a principle of STM chemical analysis as well as how field ion microscopy studies have instigated some of the later studies of scanning tunneling microscopy in surface and nanoscience applications. Copyright © 2007 John Wiley & Sons, Ltd.
Diamond and boron carbide field emission in medium vacuum
Authors: Melmed Allan J. 
Published: January 2007

AbstractField electron emission current–time and current–voltage measurements were made on single field emitters of synthetic diamond and boron carbide in medium vacuum (10−5–10−8 Torr), and two diamond specimens were characterized by scanning electron microscopy (SEM) and field ion microscopy (FIM). Generally, we found that the boron carbide emitters were less noisy than the diamond emitters, and that emission current stability improved with increasing current, at least up to 6 × 10−6 A. Use of the conventional field electron microscope (FEM) configuration enabled direct visualization of the surface condition during emission current and voltage measurements, and the combination of FIM and FEM permitted an estimation of current density for one diamond specimen, 1 × 106 A/cm2. Copyright © 2007 John Wiley & Sons, Ltd.
Characterization of precipitates in aluminium‐based alloy AW 6016
Authors: Wanderka N. , Schiffmann R. , Banhart J. 
Published: January 2007

AbstractThe aluminium‐based engineering alloy AW 6016 of nominal composition 98.44 Al–0.45 Mg–0.96 Si–0.11 Fe–0.034 Mn–0.0054 Zn–0.0038 Cr was investigated (all values are given in at.%). Heat treatment of solutionized and quenched alloys leads to an increase in hardness, which is due to the formation of small precipitates of nanometer scale size. Two complementary high‐resolution methods, namely transmission electron microscopy (TEM) and three‐dimensional atom probe (3‐DAP), are used for investigations of the precipitate evolution after annealing at 185 °C and 235 °C. At very early stages, i.e. after 5 min at 185 °C, Mg‐rich, Si‐rich and MgSi co‐clusters are observed. They are spherical and their diameter is between 1 and 3 nm. The number density of clusters as measured by 3‐DAP is 9 × 1023/m3. After ageing for 25 min and 90 min at 185 °C, GP zones and a needle‐like β″ phase are formed. Both are rich in Mg and Si. The concentration ratio of Mg to Si of the precipitates is ∼1. The number density of all precipitates after 90 min annealing time at 185 °C is 6 × 1023/m3. The needle‐like β″ precipitates at this ageing stage are about 4 nm in diameter and longer than 10 nm.The precipitates formed at 235 °C after 10 min are much larger when compared to those formed at 185 °C. They are rod‐shaped and have an average size as measured by TEM, about 50 nm in length and 3–4 nm in cross section. The concentration ratio between Mg and Si as measured by 3‐DAP is about 1. Copyright © 2007 John Wiley & Sons, Ltd.
Grain‐boundary segregation in nanocrystalline CuBi layers studied with the tomographic atom probe
Authors: Wolde‐Giorgis Daniel , Al‐Kassab Tala'at , Kirchheim Reiner 
Published: January 2007

AbstractIn an effort to prepare nanocrystalline Bi‐doped Cu layers, the Ar sputter deposition technique was applied. In previous works, polycrystalline grain growth on planar substrates was reported. On the apex of W tips with a radius of curvature of about 20–35 nm, we find columnar nanocrystalline grain growth. The Cu bilayers so prepared were characterized by means of the atom probe tomography (APT) and field ion microscopy (FIM). Lamellar structures of grain boundaries and isolated grain boundaries are observed. Without any post‐annealing after deposition, we find elevated concentrations of Bi at discrete grain boundaries and in the grains. Copyright © 2007 John Wiley & Sons, Ltd.
Genetic correlations between temperament and breeding traits in Limousin heifers
Authors: Phocas F. , Boivin X. , Sapa J. , Trillat G. , Boissy A. , Le Neindre P. 
Published: January 2007

AbstractThe aim of this study was to assess the potential consequences of selection for less aggressive or active animals during handling by estimating genetic correlations between different criteria of temperament and Limousin heifer breeding traits. Data consisted of the records collected from 1992 to 2004 at the progeny test station of Limousin AI sires. Six traits recorded during the same behavioural test – the so-called docility test – were considered to describe the heifer's temperament: aggressiveness against the handler, running time and number of escapes per minute of test period in presence or absence of the handler and a synthetic docility score accounting for the five previous components. Eight breeding traits were also considered simultaneously in the joint analysis with the five elementary temperament components: weights at 12 months and after calving (for measuring heifer growth), age at first observed oestrus (for measuring puberty) and fertility (for measuring heifer reproductive performance), calving ease score and pelvic opening (for measuring calving performance), maternal behaviour at calf's birth and milk yield (for measuring the suckling ability of the primiparous cow). REML (co)variance estimates were derived using linear multitrait sire models. Estimates of heritability were in the range of values given in the literature. Estimates of genetic correlation between temperament traits indicated that, genetically, aggressive animals also attempt to escape a lot. Consequently, their elimination will reduce both working risk and handling time for the breeder. Genetic correlations between temperament traits and breeding traits ranged from zero to favourable estimates and confirmed the very few results of the literature indicating a slight trend of less fearful heifers also being more productive, mainly because of a higher reproduction and calving performance, and, to a lesser extent, because of higher maternal abilities such as behaviour at calf's birth and milk yield.
Nanoparticles: pharmacological and toxicological significance
Authors: Medina C , Santos‐Martinez M J , Radomski A , Corrigan O I , Radomski M W 
Published: January 2007

Nanoparticles are tiny materials (<1000 nm in size) that have specific physicochemical properties different to bulk materials of the same composition and such properties make them very attractive for commercial and medical development. However, nanoparticles can act on living cells at the nanolevel resulting not only in biologically desirable, but also in undesirable effects. In contrast to many efforts aimed at exploiting desirable properties of nanoparticles for medicine, there are limited attempts to evaluate potentially undesirable effects of these particles when administered intentionally for medical purposes. Therefore, there is a pressing need for careful consideration of benefits and side effects of the use of nanoparticles in medicine. This review article aims at providing a balanced update of these exciting pharmacological and potentially toxicological developments. The classes of nanoparticles, the current status of nanoparticle use in pharmacology and therapeutics, the demonstrated and potential toxicity of nanoparticles will be discussed.British Journal of Pharmacology (2007) 150, 552–558. doi:10.1038/sj.bjp.0707130
Neurological Findings Associated with Spatial Disorders in Children
Authors: Salzarulo P , Bergès J , Pêcheux Marie-Germaine , Bounes Marika 
Published: January 2007

Spatial disabilities are usually considered either from a cognitivist point of view or as a sign of ‘minimal brain damage’. We have studied disabilities associated with spatial orientation in 60 children, aged 8 to 10, referred to us for learning disabilities. Performances on the Bender Gestalt test and on the Bergès–Lézine test for the imitation of gestures have been related to the presence or absence of neurological soft signs, psychomotor disturbances, a pathological or mixed laterality, and a pathological anamnesis: the relationships among all these factors appear to be quite complex. Difficulties in orienting arms in reference to the body may be related to neurological signs corresponding to a hypothetical brain damage. More complex imitations, involving subtle spatial relationships and reversibility, are impaired when psychomotor disturbances are present. Impairment of orientation in graphic space may result from an affective–emotional disorganisation, reflected by psychomotor troubles. All these results show how difficulties in imitating somebody else's movements and in reproducing a graphic model can be related to different kinds of neurological disorganisation, functional as well as organic.