bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Blockade of TNF-α and Interleukin-1 Action on Bone Resorption in Early Postmenopausal Women
Authors: Charatcharoenwitthaya Natthinee , Khosla Sundeep , Atkinson Elizabeth J , McCready Louise K , Riggs B Lawrence
Published: February 2007

After acute estrogen withdrawal in postmenopausal women, administration of anakinra or etanercept, specific blockers of IL-1 and TNF-α, respectively, reduced the rise in bone resorption markers to about one half of that in controls. This is consistent with an important role for these immune cytokines in mediating the effect of estrogen deficiency on bone.

Introduction: Studies in rodents have implicated increased production of interleukin (IL)-1β and TNF-α as mediators of bone loss after ovariectomy, but their roles are unclear in humans whose immune system differs markedly from that of rodents.

Materials and Methods: We administered transdermal estradiol, 0.1 mg/d, for 60 days to 42 early postmenopausal women. Estrogen treatment was discontinued, and subjects were randomly assigned to intervention groups receiving 3 wk of injections with 0.9% saline, anakinra 100 mg/d, or etanercept 25 mg/twice weekly. Bone turnover was assessed by measuring serum carboxyl-terminal telopeptide of type 1 collagen (CTX) and amino-terminal telopeptide of type 1 collagen (NTX), markers for bone resorption, and serum amino-terminal propeptide of type 1 collagen (P1NP), a marker for bone formation. Results were expressed as percent change in markers from baseline (last 2 days of estrogen treatment and days 20 and 21 of intervention).

Results: The percent changes from baseline during intervention for serum CTX, urine NTX, and serum PINP, respectively, were 43.3 ± 8.0%, 12.0 ± 7.1%, and −41.0 ± 2.5% for the control group; 25.9 ± 6.3%, 9.5 ± 4.0%, and −37.8 ± 3.0% for the anakinra group; and 21.7 ± 5.0%, 0.32 ± 3.82%, and −34.5 ± 3.9% for the etanercept group. Compared with the control group, the blunting of the increase in serum CTX fell just below the level of significance (p = 0.10) after anakinra treatment, whereas the blunting of the increase in serum CTX (p = 0.034) and in urine NTX (p = 0.048) were significant after etanercept treatment. Other changes were not significant.

Conclusions: The data are consistent with a role for TNF-α, and possibly for IL-1β, in mediating increased bone resorption during estrogen deficiency in women. Although either cytokine blocker reduced serum CTX by about one half, the effect of combined blockade could not be tested because of concerns about toxicity. The data do not exclude direct or indirect contributory roles for RANKL or for other cytokines.
Variation of Ultrasonic Parameters With Microstructure and Material Properties of Trabecular Bone: A 3D Model Simulation
Authors: Haïat Guillaume , Padilla Frédéric , Peyrin Françoise , Laugier Pascal
Published: February 2007

This study determined the influence of trabecular bone microstructure and material properties on QUS parameters using numerical simulations coupled with high-resolution synchrotron radiation μCT.

Introduction: Finite-difference time domain (FDTD) simulations coupled to 3D microstructural models of trabecular bone reconstructed from synchrotron radiation microtomography (SR-μCT) were used herein to compare and quantify the effects of bone volume fraction, microstructure, and material properties on QUS parameters.

Materials and Methods: 3D SR-μCT datasets of 30 trabecular human femoral bone specimens were used to create binary digital 3D models. We studied the sensitivity of quantitative ultrasound (QUS) to bone volume fraction by examining QUS parameters at different stages of trabecular thinning or thickening using an iterative dedicated algorithm. The sensitivity to bone material properties was also assessed by analyzing different scenarios in which density and stiffness could be varied independently. The effect of microstructure was qualitatively assessed by producing virtual bone specimens of identical bone volume fraction. Simulations of ultrasonic wave propagation through the trabecular bone volumes were performed using the FDTD simulation software SimSonic developed by our group. For each structure, both broadband ultrasonic attenuation (BUA) and speed of sound (SOS) were computed.

Results: BUA and SOS showed a strong correlation with BV/TV (r2 = 0.94, p < 10−4) and varied quasi-linearly with BV/TV at an approximate rate of 2 dB/cm.MHz and 11 m/s per percent increase of BV/TV, respectively. Bone alterations caused by variation in BV/TV between 5% and 25% had a greater impact on QUS variables (variation of BUA: 40 dB/cm.MHz; variation of SOS: 200 m/s) than variations caused by alterations of material properties realized either by a 30% change of density or 40% change of stiffness (BUA: 1.7 dB/cm.MHz; SOS: 43 m/s) or than diversity in microarchitecture (BUA:7.8 dB/cm.MHz; SOS: 36 m/s). Moreover, the sensitivity of BUA and SOS to changes in BMD by a given amount realized by a pure change in bone mass (or BV/TV) was found to be predominant over a pure change of mineralization, except for low BV/TV values, where both effects are comparable.

Conclusions: Trabecular bone microstructure (i.e., trabecular thickness) and material properties were changed to quantify the impact of specific determinants on QUS variables. In this sample of unselected autopsies, specimen variability in bone volume seemed to have a somewhat larger impact on QUS variables than the variability of the other determinants assessed. Whether this is also the case for osteoporotic patients remains to be studied.
Infectious Disease Morbidity Among Young HIV-1–Exposed But Uninfected Infants in Latin American and Caribbean Countries: The National Institute of Child Health and Human Development International Site Development Initiative Perinatal Study
Authors: Mussi-Pinhata Marisa M. , Freimanis Laura , Yamamoto Aparecida Y. , Korelitz James , Pinto Jorge A. , Cruz Maria L. S. , Losso Marcelo H. , Read Jennifer S. ,   for the National Institute of Child Health and Human Development International Site Development Initiative Perinatal Study Group
Published: February 2007

OBJECTIVE. The goal was to describe the frequency, characteristics, and correlates of infectious disease morbidity during the first 6 months of life among HIV-1–exposed but uninfected infants.

METHODS. The study population consisted of infants enrolled in the National Institute of Child Health and Human Development International Site Development Initiative Perinatal Study who were HIV-1 uninfected and had follow-up data through the 6-month study visit. Definitive and presumed infections were recorded at study visits (birth, 6–12 weeks, and 6 months).

RESULTS. Of 462 HIV-1–uninfected infants with 11644 child-weeks of observation, 283 experienced ≥1 infection. These 283 infants experienced 522 infections (1.8 infections per infant). The overall incidence rate of infections was 4.5 cases per 100 child-weeks of observation. Overall, the most common infections were skin or mucous membrane infections (1.9 cases per 100 child-weeks) and respiratory tract infections (1.7 cases per 100 child-weeks). Thirty-six percent of infants had >1 respiratory tract infection (1.8 cases per 100 child-weeks). Incidence rates of upper and lower respiratory tract infections were similar (0.89 cases per 100 child-weeks and 0.9 cases per 100 child-weeks, respectively). Cutaneous and/or oral candidiasis occurred in 48 neonates (10.3%) and 92 older infants (19.3%). Early neonatal sepsis was diagnosed in 12 infants (26.0 cases per 1000 infants). Overall, 81 of 462 (17.5%) infants were hospitalized with an infection. Infants with lower respiratory tract infections were hospitalized frequently (40.7%). The occurrence of ≥1 neonatal infection was associated with more-advanced maternal HIV-1 disease, tobacco use during pregnancy, infant anemia, and crowding. Lower maternal CD4+ cell counts, receipt of intrapartum antibiotic treatment, and country of residence were associated with postneonatal infections.

CONCLUSIONS. Close monitoring of HIV-1–exposed infants, especially those who are anemic at birth or whose mothers have more-advanced HIV-1 disease or who smoked during pregnancy, remains important.
BRCA1, a Potential Predictive Biomarker in the Treatment of Breast Cancer
Authors: James Colin R. , Quinn Jennifer E. , Mullan Paul B. , Johnston Patrick G. , Harkin D. Paul
Published: February 2007

Learning Objectives

After completing this course, the reader will be able to: List the biomarkers that are currently used and those that may be of potential use in the management of breast cancer.Explain how BRCA1 is involved in the development of both inherited and sporadic breast cancer.Discuss the potential role of BRCA1 as a determinant of response to different types of chemotherapy agents.Describe the relationship between BRCA1 and basal-like breast cancer.

CME Access and take the CME test online and receive 1 AMA PRA Category 1 Credit™ at CME.TheOncologist.com
Adrenal Masses in the Cancer Patient: Surveillance or Excision
Authors: Mitchell Ian C. , Nwariaku Fiemu E.
Published: February 2007

An increasing number of patients with a history of solid organ malignancy now undergo surveillance imaging as part of their follow-up or for evaluation of other conditions. This imaging has led to both greater identification of asymptomatic adrenal masses and subsequent confusion among clinicians regarding the evaluation and treatment. Although established algorithms exist for treating such “incidentalomas” in otherwise healthy patients, the most effective way to do so in patients with known prior or concurrent malignancies is unclear. In this review, we explore methods of biochemical testing in such patients and discuss the role of imaging techniques in their ability to differentiate benign versus malignant lesions. In this population, we examine the increasing use of biopsy and discuss current data on both surveillance and resection of lesions based on their identity. Finally, we propose an algorithm to aid the clinician in evaluating and treating these complex patients efficiently.
Intravenous Ferric Gluconate Significantly Improves Response to Epoetin Alfa Versus Oral Iron or No Iron in Anemic Patients with Cancer Receiving Chemotherapy
Authors: Henry David H. , Dahl Naomi V. , Auerbach Michael , Tchekmedyian Simon , Laufman Leslie R.
Published: February 2007

Purpose. To evaluate the safety and efficacy of intravenous (IV) sodium ferric gluconate complex (FG), oral ferrous sulfate, or no iron to increase hemoglobin (Hb) in anemic cancer patients receiving chemotherapy and epoetin alfa.

Patients and Methods. In this open-label, multicenter trial, 187 patients with chemotherapy-related anemia (Hb <11 g/dl; serum ferritin ≥100 ng/ml or transferrin saturation ≥15%) scheduled to receive chemotherapy and epoetin alfa (40,000 U subcutaneously weekly) were randomized to 8 weeks of 125 mg of IV FG weekly, 325 mg of oral ferrous sulfate three times daily, or no iron. The primary outcome was a change in Hb from baseline to endpoint, first whole-blood or red blood cell transfusion, or study withdrawal.

Results. One hundred twenty-nine patients were evaluable for efficacy (FG, n = 41; oral iron, n = 44; no iron, n = 44). Mean increase in Hb was 2.4 g/dl (95% confidence interval [CI], 2.1–2.7) for FG (p = .0092 vs. oral iron; p = .0044 vs. no iron), 1.6 g/dl (95% CI, 1.1–2.1) for oral iron (p =.7695 vs. no iron), and 1.5 g/dl (95% CI, 1.1–1.9) for no iron. Hb response (increase ≥2 g/dl) was 73% for FG (p = .0099 vs. oral iron; p = .0029 vs. no iron), 46% for oral iron (p = .6687 vs. no iron), and 41% for no iron. FG was well tolerated.

Conclusion. For cancer patients with chemotherapy-related anemia receiving epoetin alfa, FG produces a significantly greater increase in Hb and Hb response compared with oral iron or no iron, supporting more aggressive treatment with IV iron supplementation for these patients.
The Rhetoric of ICT and the New Language of Learning: A Critical Analysis of the Use of ICT in the Curricular Field
Authors: Haugsbakk Geir , Nordkvelle Yngve
Published: February 2007

This article focuses on how we perceive new technology and technological development within educational settings, and seeks to establish a critical link between the rhetoric of information and communications technology (ICT) and what Biesta called ‘the new language of learning’. Within this ‘new language’ the learner is a consumer, with needs that must be fulfilled by the teacher. This rhetoric implies that ‘teaching’ has been replaced by ‘learning’ and challenges the conventional curricula in many respects. The article applies Biesta's perspective to a concrete scrutiny of current trends in education and the introduction of ICT in education in particular. The analysis gives support to Biesta's main hypothesis, but it also indicates that the radical shift from teaching to learning is accompanied, and we might possibly say influenced, by the rhetoric connected to the use of ICT. In recent Norwegian curricular texts ICT takes a position as the rationalising tools by which teaching can be made efficient, individually designed and flexible. The intention is to critically examine the way in which teaching is more or less automatically replaced by learning, the influence the rhetoric of ICT has had, and how ICT and learning seem to be connected through merely rhetorical couplings.
Gauging the Deliverable? Educational Research in Northern Ireland
Authors: Gardner John , Gallagher Tony
Published: February 2007

This article considers the landscape for educational research in the smallest country of the United Kingdom, Northern Ireland. As elsewhere, educational research exists in political and economic circumstances that have considerable influence on its direction, nature and purpose and this article seeks to contextualise these influences. Northern Ireland differs considerably from the other three jurisdictions by virtue of it being very small (a population of circa 1.5 million), a fact that creates systemic difficulties such as capacity weaknesses in both numbers of researchers and the range of research skills available. Perhaps most importantly, however, Northern Ireland is uniquely distinguished from England, Scotland and Wales by having a proportionately large selective education system (grammar and non-selective secondary schools) and a politically and religiously divided population. This article argues that in combination with such national pressures as the Research Assessment Exercise, these contextual features result in a largely instrumental role for educational research — a tool to gauge what policy changes are deliverable. A strategic direction based on a dialogue between the government and the researcher community is therefore needed to prevent the continuation of a perceived ad hoc and fragmented system of educational research. The challenges of building a thriving research community in such circumstances also include the need to promote innovative ideas and related research, and to encourage greater inter-institutional collaboration. This in turn, it is argued, will help to create a community of practice capable of both sustaining itself in the future and making available a broader range of research competence.
The Knowledge Society and Global Dynamics in Education Politics
Authors: Jakobi Anja P.
Published: February 2007

This article explores the linkage between the idea of a knowledge society and effects of internationalisation in education policy-making. The fact that the idea of a knowledge society is widely shared is brought together with an explanation of increasing dynamics in education politics. The central argument is that the idea of a knowledge society has helped countries to increasingly perceive themselves as similar with respect to necessary educational changes. In consequence, they exchange policies which, some decades ago, would have been assumed to be bound to and determined by specific national traditions. Theoretically, the article is conceptualised in an institutionalist framework and illustrates the theoretical thoughts by the example of lifelong learning. Methods applied are content analysis, descriptive statistics and interviews.
The Infrastructure of Educational Research in Scotland
Authors: Humes Walter
Published: February 2007

This article offers a descriptive and analytical account of the current state of educational research in Scotland, viewed against the background of constitutional change within the United Kingdom and debates about the nature, function and quality of research activity and output. It starts by considering how to undertake the task in hand and argues that it is necessary to draw on a combination of institutional, developmental and interactive approaches. Thereafter the relatively disappointing Scottish results in the 2001 UK Research Assessment Exercise are reported to set the scene for subsequent efforts to improve research capacity. The role of the Scottish Executive in determining research priorities, commissioning projects and using the findings of research in helping to inform policy is outlined, taking account of important structural changes following devolution. A key development has been the Applied Educational Research Scheme (AERS), a collaborative university-led initiative, funded jointly by the Scottish Executive and the Scottish Funding Council (previously the Scottish Higher Education Funding Council). This consists both of substantive research networks and a capacity-building programme of research training for beginning and developing researchers. Established research centres, with different histories and emphases, are described in order to raise issues about the balance between applied research, linked to policy priorities, and fundamental research which seeks to develop new theories and models. The role of the Scottish Educational Research Association, which has links with the British and European Educational Research Associations, is considered. Various attempts by different bodies to promote teacher engagement in research are also described. In the final section an attempt is made to assess what progress has been made. It is concluded that while the overall climate for the conduct of educational research has improved, providing real opportunities to demonstrate the value of research, there remain a number of challenging problems. These include: issues of research quality; inadequate opportunity to undertake fundamental (as distinct from applied) research; tensions between the demands of teacher education programmes and universities' research aspirations; the risk of ‘collaboration’ becoming ‘consensus’; and the absence of a developed international perspective.
Forgetting in spatial memories acquired in a virtual environment
Authors: Tlauka Michael , Donaldson Phill K. , Wilson Duncan
Published: February 2007

This study examined forgetting in spatial memories acquired in a virtual environment. In the two experiments, participants learned the locations of eight objects. In Experiment 1, the objects were presented as photographs in either a laboratory or in an equivalent virtual environment. Irrespective of learning condition, accuracy of recall of the locations was found to deteriorate after a retention interval of approximately 1 week. In Experiment 2, following virtual learning, three groups of participants performed a series of non‐spatial tasks of low, intermediate or high difficulty. The tasks were presented in a retention interval of 2 hours. A comparison of recall accuracy before and after presentation of the interference tasks indicated that that the groups were not differentially affected by the difficulty of the retroactive interference tasks. However, the groups differed in their subjective assessment of the mental workload involved in the tasks. The results are discussed with reference to a prominent theory of forgetting. Copyright © 2007 John Wiley & Sons, Ltd.
Analytical Procedure for the Simultaneous Voltammetric Determination of Trace Metals in Food and Environmental Matrices. Critical Comparison with Atomic Absorption Spectroscopic Measurements
Authors: Melucci Dora , Torsi Giancarlo , Locatelli Clinio
Published: February 2007

An analytical procedure fit for the simultaneous determination of copper (II), chromium(VI), thallium(I), lead(II), tin(II), antimony(III), and zinc(II) by square wave anodic stripping voltammetry (SWASV) in three interdependent environmental matrices involved in foods and food chain as meals, cereal plants and soils is described. The digestion of each matrix was carried out using a concentrated HCl‐HNO3‐H2SO4 (meals and cereal plants) and HCl‐HNO3 (soils) acidic attack mixtures. 0.1 mol/L dibasic ammonium citrate pH 8.5 was employed as the supporting electrolyte. The voltammetric measurements were carried out using, as working electrode, a stationary hanging mercury drop electrode (HMDE) and a platinum electrode and an Ag|AgCl|KClsat electrode as auxiliary and reference electrodes, respectively. The analytical procedure was verified by the analyses of the standard reference materials: Wholemeal BCR‐CRM 189, Tomato Leaves NIST‐SRM 1573a and Montana Soil Moderately Elevated Traces NIST‐SRM 2711. For all the elements in the certified matrix, the precision as repeatability, expressed as relative standard deviation (sr %) was lower than 5 %. The accuracy, expressed as percentage relative error (e %) was of the order of 3‐7 %, while the detection limits were in the range 0.015‐0.103 μg/g. Once set up on the standard reference materials, the analytical procedure was transferred and applied to commercial meal samples, cereal plants and soils samples drawn in sites devoted to agricultural practice. A critical comparison with spectroscopic measurements is also discussed.
Morphological and Physiological Responses of Barley Plants Grown on Soils Characterised by Metal Toxicity and Metal Deficiency
Authors: Deriu Daniela , Calace Nicoletta , Petronio Bianca Maria , Pietroletti Marco
Published: February 2007

Aim of this work was to investigate which are the effects on barley crops grown on two different soils: a soil lacking in Cu, an essential micronutrient (A) and a naturally polluted soil rich in lead, zinc, copper (B). In particular we investigated the relationship between some ecophysiological parameters such as biomass, chlorophyll concentration and guaiacolo peroxidase activity and the chemical‐physical properties of the soils like pH, organic matter and heavy metal content. Because metals uptake by plants is strongly correlated with the bioavailable fraction rather then their total amount in a soil, we have measured also metal exchangeable forms, using a single extraction method (MgCl2 as extractant). Plants grown on soil B showed a metal content higher than background limits, whereas plants grown on soil A were characterised by a background Fe and Zn concentrations and by a tolerant Pb concentration. Conversely, Cu content in tissues of plants grown in soil A is found to be under the background limits. Copper‐deficiency plants present chlorotic leaves followed by a reduced clorophyll content, while plants grown on metals contaminated soil showed an increase of peroxidase activity.
Dioxouranium(VI)‐Carboxylate Complexes. Speciation of UO22+‐1,2,3‐Propanetricarboxylate System in NaClaq at Different Ionic Strengths and at T = 25 °C
Authors: Crea Francesco , de Stefano Concetta , Milea Demetrio , Sammartano Silvio
Published: February 2007

The formation constants of dioxouranium(VI) ‐ 1,2,3‐propanetricarboxylate [tricarballylate (3‐), TCA] complexes were determined in NaCl aqueous solutions at 0 ≤ I / mol L‐1 ≤ 1.0 and t = 25 °C, by potentiometry, ISE‐[H+] glass electrode. The speciation model obtained at each ionic strength includes the following species: ML‐, MLH0, ML24‐ and ML2H3‐ (M = UO22+ and L = TCA). The dependence on ionic strength of protonation constants of 1,2,3‐propanetricarboxylate and of the metal‐ligand complexes was modeled by the SIT (Specific ion Interaction Theory) approach and by the Pitzer equations. The formation constants at infinite dilution are [for the generic equilibrium p UO22+ + q (L3‐) + r H+ = (UO22+)p(L)qHr(2p−3q+r); βpqr]: log β110 = 6.222±0.030, log β111 = 11.251±0.009, log β121 = 7.75±0.02, log β121 = 14.33±0.06. The sequestering ability of 1,2,3‐propanetricarboxylate towards UOUO22+ was quantified by using a sigmoid Boltzman type equation.
Comparison of Time‐Resolved Fluoroimmunoassay for Determining Hexoestrol Residues in Chicken Muscle Tissues Based on Polyclonal Antibodies with Liquid Chromatography and Tandem Mass Spectrometry
Authors: Xiangqian Li , Yongming Hu , Tieming Huo , Xiaogang Chu , Chuanlai Xu
Published: February 2007

A time‐resolved fluoroimmunoassay (TR‐FIA) was developed for the determination of hexoestrol (HES) residues in animal tissues. The limit of detection (LOD) was determined to be 0.02 ng g‐1 and the limit of quantification (LOQ) was less than 0.12 ng g‐1. The results obtained by the TR‐FIA and ELISA showed a good correlation. The established TR‐FIA was validated for the determination of market chicken muscle tissues and confirmed by high‐performance liquid chromatography and tandem mass spectrometry (LC‐MS‐MS). This proposed technique could be applied to routine residue analysis.
On the Complexation of Copper (II) Ion with 2‐Hydroxybenzamide
Authors: Porto Raffaella , Furia Emilia
Published: February 2007

The complexation of the Cu2+ ion with 2‐Hydroxybenzamide (salicylamide, HL) has been studied, at 25 °C, by potentiometric measurements with a glass electrode in NaClO4 media for ionic strength ranging from 0.5 to 3 mol/dm3. The data are consistent with the formation of the complexes CuH‐1(HL)+, CuH‐2(HL)2, Cu2H‐2(HL)22+ and CuH‐2(HL). The minor species, Cu2H‐2(HL)22+ and CuH‐2(HL), amount to at least 20% of the total copper.

Elaboration of the data according to the Specific Interaction Theory yields the constants valid in the infinite dilution reference state:

 

HL ⇌ L‐ + H+
log °β011 = ‐ 8.27 ± 0.03

Cu2+ + HL ⇌ CuH‐1(HL)+ + H+
log °β111 = ‐ 3.06 ± 0.05

Cu2+ + 2 HL ⇌ CuH‐2(HL)2 + 2 H+
log °β122 = ‐ 7.72 ± 0.05

2Cu2+ + 2HL ⇌ Cu2H‐2(HL)22+ + 2 H+
log °β222 = ‐ 5.5 ± 0.1

Cu2+ + HL ⇌ CuH‐2(HL) + 2 H+
log °β121 = ‐ 10.9 ± 0.1

and the interaction coefficients (kg/mol) of complex species with medium ions: b(L‐,Na+) = 0.11 ± 0.03; b(CuH‐1(HL)+,NaClO4) = 0.17 ± 0.05; b(CuH‐2(HL)2,NaClO4) = 0.11 ± 0.05; b(Cu2H‐2(HL)22+,NaClO4) = 0.27 ± 0.1; b(CuH‐2(HL),NaClO4) = ‐ 0.03 ± 0.1.
Spectrophotometric Study of Acidity Constants of Alizarine Red S in Various Water‐Organic Solvent
Authors: Niazi Ali , Rezaei Amir Ahmad , Shahhosseini Fatemeh
Published: February 2007

The acidity constants of Alizarine Red S were determined spectrophotometrically at 25 °C and at constant ionic strength 0.1 M (KNO3) in pure water as well as in aqueous media containing variable mole percentages (5‐70 %) of organic solvents. The organic solvents used were methanol, ethanol, N,N‐dimethyl formamide (DMF), dimethyl sulfoxide (DMSO), acetonitrile and dioxan. The acidity constants of all related equilibria are estimated using the whole spectral fitting of the collected data to an established factor analysis model. DATAN program was applied for determining of acidity constants and pure spectra of different form of Alizarine Red S. The obtained results indicated that acidity constants decrease as the content of an organic solvent in the medium increases. There are linear relationship between acidity constants and the mole fraction of various organic solvents in the solvent mixtures. Effect of various solvents on acidity constants and pure spectrum of each component are also discussed.
Potentiometric Batch and Flow Injection Analysis of Betaine Hydrochloride
Authors: Badawy Sayed S. , Youssef Ahmed F. A. , Mutair Ali A.
Published: February 2007

Novel PVC membrane electrodes for the determination of betaine ion based on the formation of betaine‐tetraphenylborate (Be‐TPB) and betaine‐phosphotungstate (Be‐PT) ion‐exchangers as electroactive materials are described. The sensors show a fast, stable, near Nernstian response for 6.92 × 10‐6 to 7.94 × 10‐3 M and 1.0 × 10‐4 to 1.0 × 10‐2 M betaine hydrochloride (Be.Cl) in case of Be‐TPB electrode applying batch and flow injection analysis (FIA), respectively, and 2.95 × 10‐5 to 2.26 × 10‐3 M and 3.16 × 10‐5 to 1.0 × 10‐2 M in case of Be‐PT electrode for batch and FIA electrodes, respectively, at 25 °C over the pH range of 3.5‐10 with a cationic slope of 60.2 and 59.1 mV decade‐1 and a fast potential response of ≤ 15 s. The lower detection limits are 7.94 × 10‐6 and 3.18 × 10‐5 M Be.Cl for Be‐TPB and Be‐PT electrodes, respectively. Selectivity coefficient data for some common inorganic cations, sugars, amino acids and the components other than betaine, of the mixed drug investigated show negligible interference. The electrodes have been applied to the direct potentiometric determination of betaine hydrochloride in water and in a pharmaceutical preparation under batch and FIA conditions. Potentiometric titrations of Be.Cl with NaTPB and PTA as titrants were monitored with the developed betaine electrodes as an end point indicator electrode. The determination of Be.Cl shows an average recovery of 100.8 % with mean relative standard deviation of 0.61 %. The effect of temperature on the electrodes was also studied.
Simultaneous Spectrophotometric Determination of Cobalt and Nickel by Partial Least Square Regression in Micellar Media
Authors: Kaur Varinder , Malik Ashok Kumar , Verma Neelam
Published: February 2007

Diphenycarbazone has been used for the simultaneous determination of cobalt and nickel by partial least square regression method. DPC complexes of cobalt and nickel at pH 7‐10 are of pink color, which are soluble in TX‐100 micellar media. A partial least square multivariate calibration method for the analysis of binary mixtures of cobalt and nickel was developed. The total relative standard error for applying the PLS method was calculated. The accuracy and reproducibility of the determination method for various known amounts of Co(II) and Ni(II) in their binary mixtures were tested. The effects of diverse ions on the determination of cobalt and nickel to investigate the selectivity of the method were also studied. The proposed method was applied to the synthetic binary mixtures, alloys and pharmaceutical samples.
Determination of Cobalt at ng ml‐1 Level in Water Using the Electrophilic Substiution Complexation between Co(II) and Chlorophosphonazo‐ p‐Cl‐Cu(II) Complex
Authors: Zhao Xue‐Tao , Zhao He‐Ping , Le Yi‐Quan , Zeng Teng , Gao Hong‐Wen
Published: February 2007

The chromophore chlorophosphonazo‐p‐Cl (PCCPA) was used to complex Co(II) and Cu(II) at pH 9.18. The formation of Co(PCCPA)2 and Cu(PCCPA)2 complexes were characterized by the spectral correction technique. Co(II) could competitively substitute Cu(II) from the Cu(II)‐PCCPA complex via electrophilic effect. With the assistance of the light‐absorption ratio variation approach, the electrophilic substitution complexation showed a high selectivity and good sensitivity with 1.9 ng mL‐1 of LOD. The proposed method has been applied to the direct detection of Co(II) in surface water and wastewater with good percent of recovery.
Sexual dimorphism of the dental tissues in human permanent mandibular canines and third premolars
Authors: Saunders Shelley R. , Chan Andrea H.W. , Kahlon Bonnie , Kluge Hagen F. , FitzGerald Charles M.
Published: February 2007

Methods of measuring tissue area from images of longitudinal thin tooth sections have been used to assess sexual dimorphism in the permanent dentition. The aim of this study was to demonstrate the extent of sexual dimorphism within the coronal tissue proportions of permanent mandibular canines and premolars, using area measurements of the enamel and dentine‐pulp core. The sample consisted of embedded “half‐tooth” sections from 45 individuals, all of known age‐at‐death and sex, collected from the St. Thomas' Anglican Church historic (1821–1874) cemetery site in Belleville, ON, Canada. The relative dentine‐pulp area of the third premolars and canines displayed high levels of sexual dimorphism, as well as statistically significant mean differences between the sexes. The male canines and premolars have significantly more dentine than their female counterparts, as well as relatively more dentine with respect to overall crown size. The female canines and premolars have significantly more enamel relative to overall crown area than those of the males. These results suggest that relative area measures of crown tissues are more predictable measures of sexual dimorphism than absolute measures, and tissue proportions may remain constant despite intrasex variation in overall tooth crown size. Am J Phys Anthropol, 2007. © 2007 Wiley‐Liss, Inc.
Stable isotope evidence for 1500 years of human diet at the city of York, UK
Authors: Müldner Gundula , Richards Michael P.
Published: February 2007

We present here the results of a large‐scale diachronic palaeodietary (carbon and nitrogen isotopic measurements of bone collagen) study of humans and animals from a single site, the city of York (U.K.), dating from the Roman period to the early 19th century. The human sample comprises 313 burials from the cemeteries of Trentholme Drive and Blossom Street (Roman), Belle Vue House (Anglo‐Saxon), Fishergate (High and Later Medieval), and All Saints, Pavement (Later and Post‐Medieval). In addition, 145 samples of mammal, fish and bird bone from the sites of Tanner Row and Fishergate were analyzed. The isotope data suggest dietary variation between all archaeological periods, although the most significant change was the introduction of significant quantities of marine foods in the Medieval periods. These are first evident in the diet of a small group of individuals from the High Medieval cemetery at Fishergate, although they were consumed almost universally in the following periods. The human isotope values are also remarkable due to unusually elevated δ15N ratios that are not sufficiently explained by the comparably small enrichment in 13C that accompanies them. We discuss the possible reasons behind this and the archaeological significance of the data set. Am J Phys Anthropol, 2007. © 2007 Wiley‐Liss, Inc.
Potential applications of urinary C‐peptide of insulin for comparative energetics research
Authors: Sherry Diana S. , Ellison Peter T.
Published: February 2007

The study of comparative energetics offers a valuable way to identify broad ecological principles and assess the functional significance of energetic adaptations during the course of evolution. Yet, the quantification of energetic status for nonhuman primates under natural conditions remains one of the most challenging aspects of comparative energetics research. Here, we report on the development of a noninvasive field method for measuring energetic status in great apes, humans, and possibly other nonhuman primates. Specifically, we have explored measurement of a urinary metabolite of insulin (C‐peptide) as a physiological marker of energetic condition in chimpanzees and orangutans. We performed three validation studies and successfully measured C‐peptide in urine samples from captive chimpanzees, wild chimpanzees, and wild orangutans. Urinary C‐peptide measures gave indications of being a reliable signal of energetic status in both species. For chimpanzees and orangutans in the wild, baseline urinary C‐peptide levels were higher during periods of fruit abundance than periods of low fruit availability. Urinary C‐peptide levels were also higher for well‐fed captive chimpanzees compared with wild chimpanzees. Although sample size was small, top‐ranking male chimpanzees showed higher C‐peptide levels in the wild than low‐ranking males only during the period of fruit abundance. These preliminary results indicate that further development of the urinary C‐peptide method could expand opportunities to quantify energetic condition for great apes in the wild and generate new data for comparative research. We highlight specific applications for studying great ape reproduction as well as the nutritional ecology of human foragers. Am J Phys Anthropol, 2007. © 2007 Wiley‐Liss, Inc.
Correlations between deciduous and permanent tooth morphology in a European American sample
Authors: Edgar H.J.H. , Lease L.R.
Published: February 2007

The expression of dental morphological characteristics is partially genetically controlled, and is assumed to be similar in deciduous and permanent dentitions. However, there are few published data comparing normal morphological variation between the two dentitions in the same individual. For the current study, data were collected from European Americans (N = 54) whose teeth were cast both as children and adults. We observed 19 trait expressions in deciduous and permanent dentitions. Deciduous traits were scored based on Hanihara's and Sciulli's descriptions, while permanent teeth were scored using the ASU dental anthropology system. The two dentitions' scores were compared using Goodman–Kruskal's Gamma (γ) in the original, commonly used systems as well as in a new, shared scale to which the scores were converted. Observations were also dichotomized in both formats and compared using tetrachoric correlation. We expected high correlations between the two dentitions and for both statistics to yield similar results. For the original scores, γ correlations vary from −1.0 to 0.68; tetrachoric correlations vary from 0.04 to 0.67. For the shared scale scores, γ correlations range from −1.0 to 1.0 and tetrachoric correlations range between −0.47 and 0.8. Several traits showed no correlation in either test. Overall, categorical data analysis returned more positive moderate to high correlations than tetrachoric correlation analysis, and shared scale tests resulted in more correlations than did tests of data in the original scoring systems. These results reflect differences in commonly used scoring systems, variation in rarely occurring traits, different strengths of trait expression, and complex genetic/environmental interactions. Am J Phys Anthropol, 2007. © 2007 Wiley‐Liss, Inc.
Experience‐dependent recapture rates and reproductive success in male grey mouse lemurs (Microcebus murinus)
Authors: Schmelting Barthel , Zimmermann Elke , Berke Olaf , Bruford Michael W. , Radespiel Ute
Published: February 2007

Male mating tactics can vary according to the potential for scramble or contest competition but also as a consequence of individual characteristics, such as body condition and previous experience. The influence of experience, i.e., residency, on male recapture rates and reproductive success was studied in a population of free‐living grey mouse lemurs. Long‐term capture data from 320 individuals revealed that both sexes had very low recapture probabilities within their first year in the study population, but recapture rates declined less sharply during the following years. Capture results and telemetric analyses on 12 focal males revealed that resident males had larger body mass and larger home ranges than new males. Home range size correlated with the number of accessible females, indicating that resident males had higher probabilities to meet mates than new males. The reproductive success of 132 candidate fathers, representing both resident and new males, was determined by means of molecular genotyping. Paternity determination was successful in 38 cases (success rate: 19%). Sixteen resident males and seventeen new males sired offspring. However, in relation to the number of candidate fathers being present in the mating season, resident males were twice as likely to reproduce successfully as new males. These findings suggest experience‐dependent reproductive tactics that most likely correspond to a differential spatial knowledge of resources, mates and potential threats. The results generally agree with the predictions made for a scramble competition regime and demonstrate substantial behavioral plasticity in a nocturnal primate species with a dispersed multi‐male/multi‐female mating system. Am J Phys Anthropol, 2007. © 2007 Wiley‐Liss, Inc.
Regional variation in the postcranial robusticity of late upper paleolithic humans
Authors: Shackelford Laura L.
Published: February 2007

Early modern humans from the European Upper Paleolithic (UP) demonstrate trends in postcranial biomechanical features that coincide with the last glacial maximum (LGM). These features have been interpreted as evidence that ecological changes of the LGM played a critical role in cultural and biological adaptation in European UP populations. In areas outside of Europe, similar environmental changes occurred with the LGM. This analysis introduces postcranial material from the Late Upper Paleolithic (LUP) of North Africa and Southeast Asia and tests two related hypotheses: 1) LUP samples across the Old World had similar patterns of postcranial robusticity and 2) relative to an available Early Upper Paleolithic (EUP) sample, regional LUP samples demonstrate similar trends in robusticity that may be attributable to climatic effects of the LGM. Cross‐sectional geometric data of the humeri and femora were obtained for 26 EUP and 100 LUP humans from Europe, Africa, and Asia. Despite regional differences, LUP samples are similar relative to the EUP sample. In the humerus, bilateral asymmetry decreases in all LUP samples relative to the EUP sample. In the femur, LUP samples demonstrate increasingly circular femoral midshaft sections, reflecting reduced anteroposterior bending strength relative to the EUP sample. These patterns suggest changes in subsistence behavior and mobility after the LGM across the Old World that are most consistent with reduced mobility and broad‐spectrum resource exploitation. Am J Phys Anthropol, 2007. © 2007 Wiley‐Liss, Inc.
Body size prediction from juvenile skeletal remains
Authors: Ruff Christopher
Published: February 2007

There are currently no methods for predicting body mass from juvenile skeletal remains and only a very limited number for predicting stature. In this study, stature and body mass prediction equations are generated for each year from 1 to 17 years of age using a subset of the Denver Growth Study sample, followed longitudinally (n = 20 individuals, 340 observations). Radiographic measurements of femoral distal metaphyseal and head breadth are used to predict body mass and long bone lengths are used to predict stature. In addition, pelvic bi‐iliac breadth and long bone lengths are used to predict body mass in older adolescents. Relative prediction errors are equal to or smaller than those associated with similar adult estimation formulae. Body proportions change continuously throughout growth, necessitating age‐specific formulae. Adult formulae overestimate stature and body mass in younger juveniles, but work well in 17‐year‐olds from the sample, indicating that in terms of body proportions they are representative of the general population. To illustrate use of the techniques, they are applied to the juvenile Homo erectus (ergaster) KNM‐WT 15000 skeleton. New body mass and stature estimates for this specimen are similar to previous estimates derived using other methods. Body mass estimates range from 50 to 53 kg, and stature was probably slightly under 157 cm, although a precise stature estimate is difficult to determine due to differences in linear body proportions between KNM‐WT 15000 and the Denver reference sample. Am J Phys Anthropol, 2007. © 2007 Wiley‐Liss, Inc.
Population continuity or population change: Formation of the ancient Egyptian state
Authors: Zakrzewski Sonia R.
Published: February 2007

The origins of the ancient Egyptian state and its formation have received much attention through analysis of mortuary contexts, skeletal material, and trade. Genetic diversity was analyzed by studying craniometric variation within a series of six time‐successive Egyptian populations in order to investigate the evidence for migration over the period of the development of social hierarchy and the Egyptian state. Craniometric variation, based upon 16 measurements, was assessed through principal components analysis, discriminant function analysis, and Mahalanobis D2 matrix computation. Spatial and temporal relationships were assessed by Mantel and Partial Mantel tests. The results indicate overall population continuity over the Predynastic and early Dynastic, and high levels of genetic heterogeneity, thereby suggesting that state formation occurred as a mainly indigenous process. Nevertheless, significant differences were found in morphology between both geographically‐pooled and cemetery‐specific temporal groups, indicating that some migration occurred along the Egyptian Nile Valley over the periods studied. Am J Phys Anthropol, 2007. © 2007 Wiley‐Liss, Inc.
When specialized sites are important for synapsis and the distribution of crossovers
Authors: Joyce Eric F. , McKim Kim S.
Published: February 2007

In C. elegans and D. melanogaster, specialized sites have an important role in meiotic recombination. Recent evidence has shown that these sites in C. elegans have a role in synapsis. Here we compare the initiation of synapsis in organisms with specialized sites and those without. We propose that, early in prophase, synapsis requires an initiator to overcome inhibitory factors that function to prevent synaptonemal complex (SC) formation between nonhomologous sequences. These initiators of SC formation can be stimulated by crossover sites, possibly other types of recombination sites and also specialized sites where recombination does not occur. BioEssays 29: 217–226, 2007. © 2007 Wiley Periodicals, Inc.
Regulation of chemotactic networks by ‘atypical’ receptors
Authors: Comerford Iain , Litchfield Wendel , Harata‐Lee Yuka , Nibbs Robert J.B. , McColl Shaun R.
Published: February 2007

Directed cell migration is a fundamental component of numerous biological systems and is critical to the pathology of many diseases. Although the importance of secreted chemoattractant factors in providing navigational cues to migrating cells bearing specific chemoattractant receptors is now well‐established, how the function of these factors is regulated is not so well understood and may be of key importance to the design of new therapeutics for numerous human diseases. While regulation of migration clearly takes place on a number of different levels, it is becoming clear that so‐called ‘atypical’ receptors play a role in scavenging, or altering the localisation of, chemoattractant molecules such as chemokines and complement components. These receptors do this through binding and/or internalising their chemoattractant ligands without activating signal transduction cascades leading to cell migration. The atypical chemokine receptor family currently comprises the receptors D6, DARC and CCX‐CKR. In this review, we discuss the evidence from in vitro and in vivo studies that these receptors play a role in regulating cell migration, and speculate that other orphan receptors may also belong to this family. Furthermore, with the advent of gene therapy on the horizon, the therapeutic potential of these receptors in human disease is also considered. BioEssays 29: 237–247, 2007. © 2007 Wiley Periodicals, Inc.
The importance of stress and genetic variation in human aggression
Authors: Craig Ian W.
Published: February 2007

Both genetic and environmental factors have key roles in determining aggressive tendencies. In particular, reaction to stress appears to be an important factor in precipitating aggressive episodes and individuals may vary in their ability to cope with stressful environments depending on their genetic make up. Evidence from humans and primates indicates that adverse rearing conditions may interact with variants in stress and neurotransmitter pathway genes leading to antisocial and/or violent behaviour. Common alleles of some serotonin pathway genes, including those involved in its degradation (monoamine oxidase A, MAOA), or its re‐uptake into pre‐synaptic neurones (serotonin transporter, SERT) have been shown to confer functional variation. Examination of the interaction between the alleles of such polymorphisms (in particular those affecting MAOA) and environmental stressors suggest that they may provide protection against, or increase sensitivity to, abusive upbringing; an observation that may explain part of the variability in developmental outcomes associated with maltreatment. BioEssays 29: 227–236, 2007. © 2007 Wiley Periodicals, Inc.