bluuebunny/crossref_metadata_2025 huggingface dataset:
Atomic arrangements of (Ga1−xMnx)N nanorods grown on Al2O3 substrates
Authors: Lee K. H. , Lee J. Y. , Jung J. H. , Kim T. W. , Jeon H. C. , Kang T. W.
Published: April 2008

X-ray diffraction (XRD) and selected area electron diffraction pattern (SADP) results showed that the (Ga1−xMnx)N nanorods had preferential c-axial growth direction. Transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) images showed that one-dimensional (Ga1−xMnx)N nanorods without defects had c-axis-oriented crystalline wurzite structures. Atomic arrangements for the (Ga1−xMnx)N nanorods grown on the Al2O3 (0001) substrates are described on the basis of the XRD, the TEM, the SADP, and the HRTEM results.
High field tunneling as a limiting factor of maximum energy density in dielectric energy storage capacitors
Authors: Chen Qin , Wang Yong , Zhou Xin , Zhang Q. M. , Zhang Shihai
Published: April 2008

In several low loss dielectric materials, it was observed that the energy loss remains very small under low and medium electric fields but dramatically increases at high field which is believed to be due to tunneling current. The increase of tunneling current at high field is due to the decrease of barrier width and height and is a universal phenomenon in all dielectric materials. Due to the requirement of high energy efficiency, high field conduction places a limit for the maximum operation field, which could be lower than the breakdown field and act as the limiting factor of energy density.
Weak ferromagnetism and ferroelectricity in K3Fe5F15
Authors: Blinc Robert , Tavčar Gašper , Žemva Boris , Hanžel Darko , Cevc Pavle , Filipič Cene , Levstik Adrijan , Jagličić Zvonko , Trontelj Zvonko , Dalal Naresh , Ramachandran Vasanth , Nellutla Saritha , Scott James F.
Published: April 2008

Here, we report on the observation of a weak ferromagnetic transition at TN=122K in a K3Fe5F15 system which is ferroelectric and ferroelastic below Tc=490K. The magnetization and the susceptibility continuously increase with decreasing T down to 2K. The Mössbauer spectra show a spontaneous magnetic ordering and at least three sites corresponding to Fe2+ and Fe3+. The ratio between Fe2+ and Fe3+ is 60:40. At 6K, there are two magnetically ordered sextets with internal fields of 585 and 263kOe. The “slim” hysteresis loops observed are as well characteristic of weak ferromagnetism. At 122K and at low frequencies, the system shows dielectric anomaly characteristic of magnetoelectric behavior.
Properties of ceramic honeycomb cathodes
Authors: Friedman M. , Myers M. C. , Chan Y. , Sethian J. D.
Published: April 2008

A high current electron beam was emitted from slabs of ceramic honeycomb that were placed 2mm in front of the primary electron emitters. Inside the ceramic honeycomb pores, the primary electrons are multiplied many folds by a secondary emission process creating plasma from which the electron beam was emitted. Measurements show that there was no anode-cathode gap closure during the pulse duration and a uniform current density distribution was observed on the anode. Contrary to the measurements of “conventional” large area field emission cathodes, no transit time instability was observed.
Low-power dihexylquaterthiophene-based thin film transistors for analog applications
Authors: Serban Dana A. , Kilchytska Valeria , Vlad A. , Martin-Hoyas Ana , Nysten B. , Jonas A. M. , Geerts Y. H. , Lazzaroni R. , Bayot V. , Flandre D. , Melinte S.
Published: April 2008

We have optimized dihexylquaterthiophene-based thin film transistors for low-power consumption and have studied their characteristics for potential introduction in analog circuits. Bottom-gate devices with Pd source and drain electrodes have been fabricated by employing different gate dielectrics. Transistors with very thin (<10nm) silicon oxynitride dielectrics display subthreshold swing values below 100mV/decade, cutoff frequencies approaching the kilohertz range and intrinsic gain around 45dB, suggesting that they are promising candidates for low-power analog integration.
High frequency pressure oscillator for microcryocoolers
Authors: Vanapalli S. , ter Brake H. J. M. , Jansen H. V. , Zhao Y. , Holland H. J. , Burger J. F. , Elwenspoek M. C.
Published: April 2008

Microminiature pulse tube cryocoolers should operate at a frequency of an order higher than the conventional macro ones because the pulse tube cryocooler operating frequency scales inversely with the square of the pulse tube diameter. In this paper, the design and experiments of a high frequency pressure oscillator is presented with the aim to power a micropulse tube cryocooler operating between 300 and 80K, delivering a cooling power of 10mW. Piezoelectric actuators operate efficiently at high frequencies and have high power density making them good candidates as drivers for high frequency pressure oscillator. The pressure oscillator described in this work consists of a membrane driven by a piezoelectric actuator. A pressure ratio of about 1.11 was achieved with a filling pressure of 2.5MPa and compression volume of about 22.6mm3 when operating the actuator with a peak-to-peak sinusoidal voltage of 100V at a frequency of 1kHz. The electrical power input was 2.73W. The high pressure ratio and low electrical input power at high frequencies would herald development of microminiature cryocoolers.
A microfabricated sensor for thin dielectric layers
Authors: Fierlinger P. , DeVoe R. , Flatt B. , Gratta G. , Green M. , Kolkowitz S. , Leport F. , Montero Diez M. , Neilson R. , O’Sullivan K. , Pocar A. , Wodin J.
Published: April 2008

We describe a sensor for the measurement of thin dielectric layers capable of operation in a variety of environments. The sensor is obtained by microfabricating a capacitor with interleaved aluminum fingers, exposed to the dielectric to be measured. In particular, the device can measure thin layers of solid frozen from a liquid or gaseous medium. Sensitivity to single atomic layers is achievable in many configurations and, by utilizing fast, high sensitivity capacitance readout in a feedback system onto environmental parameters; coatings of few layers can be dynamically maintained. We discuss the design, readout, and calibration of several versions of the device optimized in different ways. We specifically dwell on the case in which atomically thin solid xenon layers are grown and stabilized, in cryogenic conditions, from a liquid xenon bath.
Oblique Hanle effect in semiconductor spin transport devices
Authors: Li Jing , Huang Biqin , Appelbaum Ian
Published: April 2008

Spin precession and dephasing (“Hanle effect”) provide an unambiguous means to establish the presence of spin transport in semiconductors. We compare theoretical modeling with experimental data from drift-dominated silicon spin-transport devices, illustrating the nontrivial consequences of employing oblique magnetic fields (due to misalignment or intentional, fixed in-plane field components) to measure the effects of spin precession. Model results are also calculated for Hanle measurements under conditions of diffusion-dominated transport, revealing an expected Hanle peak-widening effect induced by the presence of fixed in-plane magnetic bias fields.
Tuning of Ag work functions by self-assembled monolayers of aromatic thiols for an efficient hole injection for solution processed triisopropylsilylethynyl pentacene organic thin film transistors
Authors: Hong Jung-Pyo , Park Aee-Young , Lee Seonghoon , Kang Jihoon , Shin Nayool , Yoon Do Y.
Published: April 2008

We demonstrate tuning of hole injection barriers in bottom contact triisopropylsilylethynyl pentacene (TIPS-pentacene) organic thin film transistors (OTFTs) by forming the self-assembled monolayers (SAMs) of thiophenol, 4-fluorothiophenol, or pentafluorothiophenol on the pristine Ag electrode. The work functions of SAM-treated Ag electrodes are measured by Kelvin probe method. The TIPS-pentacene OTFT devices were fabricated by a drop-cast method with a micropipette like an inkjet printing. The OTFTs with pentafluorothiophenol-Ag electrodes as source and drain exhibit carrier mobility of 0.17cm2∕Vs and on/off current ratio of 105 because of almost no hole injection barrier to TIPS pentacenes. The SAM-treated Ag electrodes are robust over repeated electrical scans of 100cycles.
Pattern evolution due to energetic solid-state diffusion front in nanoscale thin film
Authors: Aurongzeb Deeder
Published: April 2008

We report the study on oscillatory pattern/domain formation due to energetic solid-state reaction in a metallic multilayer thin film using a scanning probe microscope. The observed oscillatory patterns become more ordered as the total thickness changed from 50nmto1.2μm. At higher thickness, a nonlinear cross oscillation pattern is also observed, which we attribute to spinning wave. The observed oscillation is modeled in terms of perturbation in the thermal wave. Magnetization measurement shows increased coercivity for the reacted film.
Hysteresis-free organic field-effect transistors and inverters using photocrosslinkable poly(vinyl cinnamate) as a gate dielectric
Authors: Jang Jaeyoung , Kim Se Hyun , Nam Sooji , Chung Dae Sung , Yang Chanwoo , Yun Won Min , Park Chan Eon , Koo Jae Bon
Published: April 2008

We have fabricated organic field-effect transistors (OFETs) and inverters using photocrosslinkable poly(vinyl cinnamate) (PVCN) as a gate dielectric. The photocrosslinked PVCN dielectric film has superior insulating properties and does not require thermal curing. The high water resistance of the dielectric, which arises because PVCN is hydroxyl group-free, means that the devices were found to be hysteresis-free in all operations. The OFETs with the PVCN dielectric were found to exhibit a carrier mobility of 0.51cm2∕Vs, an on/off ratio of 106, and a subthreshold swing of 0.913V/decade. An organic inverter consisting of two OFETs exhibited a high inverter gain of 17.9.
Single electron tunneling and Coulomb blockade effect in HfAlO∕Au nanocrystals/HfAlO trilayer nonvolatile memory structure
Authors: Chan K. C. , Lee P. F. , Dai J. Y.
Published: April 2008

Single electron tunneling and Coulomb blockade effect have been observed in the HfAlO∕Au nanocrystals/HfAlO trilayer floating gate nonvolatile memory structure. This trilayer floating gate memory structure exhibits a significant memory window, and resonant tunneling current peaks and Coulomb staircase are obtained at 20K low temperature. Compared to the ordinary single electron devices, this is the first time that a clear single electron tunneling oscillation has been observed in the floating gate memory structure. This resonant tunneling phenomenon in floating gate memory may open a door toward application as single electron device.
Configurational, electronic entropies and the thermoelectric properties of nanocarbon ensembles
Authors: Gruen Dieter M. , Bruno Paola , Xie Ming
Published: April 2008

Reaction of disperse ultrananocrystalline diamond (UNCD) and mixtures of UNCD containing 10%–20% nanoboron carbide (B4C) with methane gas at temperatures near 1200K results in mechanically rigid compacts called nanocarbon ensembles (NCE) and boron-doped NCE, respectively. Seebeck coefficient and electrical conductivity results lead to strongly temperature dependent power factors that increase 30–40 fold for boron containing ensembles compared to undoped material. It is likely that boron substitutional doping of nanographite crystallites results in a multiplicity of electronic states within a narrow energy band around the Fermi level leading to an increase in configurational electronic entropy.
Influence of nitric oxide during maturation on bovine oocyte meiosis and embryo development in vitro
Authors: Schwarz Kátia R. L. , Pires Pedro R. L. , Adona Paulo R. , Câmara de Bem Tiago H. , Leal Cláudia L. V.
Published: April 2008

The effect of s-nitroso-n-acetyl-l,l-penicillamine (SNAP, a nitric oxide donor) during in vitro maturation (IVM) on nuclear maturation and embryo development was investigated. The effect of increasing nitric oxide (NO) during prematuration or maturation, or both, on embryo development was also assessed. 10–3 m SNAP nearly blocked oocytes reaching metaphase II (MII) (7%, P < 0.05) while 10–5 m SNAP showed intermediate proportions (55%). For 10–7 m SNAP and controls (without SNAP), MII percentages were similar (72% for both, P > 0.05), but superior to the other treatment groups (P < 0.05). Blastocyst development, however, was not affected (38% for all treatments, P < 0.05). TUNEL-positive cells in hatched blastocysts (Day 9) increased when IVM included 10–5 m SNAP (8 v. 3 to 4 cells in the other treatments, P > 0.05), without affecting total cell numbers (240 to 291 cells, P > 0.05). When oocytes were prematured followed by IVM with or without 10–7 m SNAP, during either culture period or both, blastocyst development was similar (26 to 40%, P > 0.05). When SNAP was included during both prematuration and IVM, the proportion of Day 9 hatched embryos increased (28% v. 14 to 19% in the other treatments, P < 0.05). Apoptotic cells, however, increased when SNAP was included (6 to 10 cells) in comparison to prematuration and maturation without SNAP (3 cells, P < 0.05). NO may be involved in meiotic progression and apoptosis during embryo development.
Ethnic Diversity in Bulgaria: Institutional Arrangements and Domestic Discourse*
Authors: Rechel Bernd
Published: April 2008

This article examines the application of the concepts of minority rights, racism and multiculturalism to the case of Bulgaria. It explores how—if at all—these concepts have been accommodated within the domestic discourse on ethnic relations. Overall, it will be seen that Bulgaria has been slow to face up to its multi-ethnic reality: apart from the cessation of communist assimilation campaigns, hardly any positive minority rights were adopted after 1989. There were, however, clear changes in the discourse on ethnic relations, in particular regarding the notion of the “Bulgarian ethnic model,” which now figures prominently in the discourse of most political parties.
Evaluation of the Developmental Toxicity of Linalool in Rats
Authors: Politano Valerie T , Lewis Elise M , Hoberman Alan M , Christian Mildred S , Diener Robert M , Api Anne Marie
Published: April 2008

The developmental toxicity of linalool, a widely used fragrance ingredient, was evaluated in presumed pregnant Sprague-Dawley rats (25/group). Oral dosages of 0, 250, 500, or 1000 mg/kg/day linalool were administered by gavage on gestational days 7 to 17. The presence of spermatozoa and/or a copulatory plug in situ was designated as gestational day 0. Rats were observed for viability, clinical signs, body weights, and feed consumption. Caesarean sectioning and necropsy occurred on gestational day 21. Uteri were examined for number and distribution of implantations, live and dead fetuses, and early and late resorptions. Numbers of corpora lutea were also recorded. Fetuses were weighed and examined for gender, gross external changes, and soft tissue or skeletal alterations. There were no maternal deaths, clinical signs, or gross lesions that were considered related to linalool. During the dosage period, mean relative feed consumption was significantly reduced by 7% and mean body weight gains were reduced by 11% at 1000 mg/kg/day. During the postdosage period, feed consumption values at 1000 mg/kg/day were significantly higher than vehicle control values, which corresponded to the increase in body weight gains during this period. Caesarean section and litter parameters, as well as fetal alterations, were not affected by linalool at any of the three dosages tested. On the basis of these data, the maternal no observed adverse effect level (NOAEL) of linalool is 500 mg/kg/day, whereas the developmental NOAEL is ≥ 1000 mg/kg/day. It is concluded that linalool is not a developmental toxicant in rats at maternal doses of up to 1000 mg/kg/day.
Use of the HemoCue® near patient testing device to measure the concentration of haemoglobin in suction fluid at elective Caesarean section*
Authors: Gupta A. , Wrench I. J. , Feast M. J. , Alderson J. D.
Published: April 2008

We have investigated the suitability of the HemoCue® photometer to measure the concentration of haemoglobin in suction fluid obtained at elective caesarean section in 30 women. Laboratory analysis was used as a gold standard against which values generated by the HemoCue were compared. We used the method of Bland and Altman to analyse the data. The bias and the limits of agreement were −0.013 and −0.39 to 0.36 mg.dl−1 respectively, indicating a good level of agreement. Mean (SD) total blood loss calculated using these data, combined with the weight of the swabs, was consistently greater than clinical estimation: 768 (496) ml versus 506 (249) ml respectively (p < 0.001). We have found that the HemoCue near patient testing device may be used to estimate blood loss accurately in the suction fluid obtained at elective Caesarean section.
Postoperative muscle weakness in a patient recently treated with infliximab
Authors: Drummond A. D. , Williamson R. M. , Silverdale M. A. , Rothwell M. P.
Published: April 2008

We present a case of profound postoperative muscle weakness in a patient who had been treated with infliximab, and whose weakness had not manifested pre‐operatively. We believe this to be the first case report of infliximab‐related muscle weakness manifesting immediately after anaesthesia.
Pharmacokinetics of intravenous and oral midazolam in plasma and saliva in humans: usefulness of saliva as matrix for CYP3A phenotyping
Authors: Link Bettina , Haschke Manuel , Grignaschi Nathalie , Bodmer Michael , Aschmann Yvonne Zysset , Wenk Markus , Krähenbühl Stephan
Published: April 2008

WHAT IS ALREADY KNOWN ABOUT THE SUBJECT

• Midazolam is a frequently used probe drug for CYP3A phenotyping in plasma. Midazolam and its hydroxy‐metabolites can be detected in saliva.

WHAT THIS STUDY ADDS

• The concentrations of midazolam and its hydroxy‐metabolites are much lower in saliva than in plasma, but the midazolam concentrations in both matrices show a significant linear correlation.

• Saliva appears to be a suitable matrix for CYP3A phenotyping with midazolam, but very sensitive methods are required due to the low concentrations of midazolam and its hydroxy‐metabolites.

AIMS

To compare midazolam kinetics between plasma and saliva and to find out whether saliva is suitable for CYP3A phenotyping.

METHODS

This was a two way cross‐over study in eight subjects treated with 2 mg midazolam IV or 7.5 mg orally under basal conditions and after CYP3A induction with rifampicin.

RESULTS

Under basal conditions and IV administration, midazolam and 1′‐hydroxymidazolam (plasma, saliva), 4‐hydroxymidazolam and 1′‐hydroxymidazolam‐glucuronide (plasma) were detectable. After rifampicin, the AUC of midazolam [mean differences plasma 53.7 (95% CI 4.6, 102.9) and saliva 0.83 (95% CI 0.52, 1.14) ng ml−1 h] and 1′‐hydroxymidazolam [mean difference plasma 11.8 (95% CI 7.9 , 15.7) ng ml−1 h] had decreased significantly. There was a significant correlation between the midazolam concentrations in plasma and saliva (basal conditions: r = 0.864, P < 0.0001; after rifampicin: r = 0.842, P < 0.0001). After oral administration and basal conditions, midazolam, 1′‐hydroxymidazolam and 4‐hydroxymidazolam were detectable in plasma and saliva. After treatment with rifampicin, the AUC of midazolam [mean difference plasma 104.5 (95% CI 74.1, 134.9) ng ml−1 h] and 1′‐hydroxymidazolam [mean differences plasma 51.9 (95% CI 34.8, 69.1) and saliva 2.3 (95% CI 1.9, 2.7) ng ml−1 h] had decreased significantly. The parameters separating best between basal conditions and post‐rifampicin were: (1′‐hydroxymidazolam +  1′‐hydroxymidazolam‐glucuronide)/midazolam at 20–30 min (plasma) and the AUC of midazolam (saliva) after IV, and the AUC of midazolam (plasma) and of 1′‐hydroxymidazolam (plasma and saliva) after oral administration.

CONCLUSIONS

Saliva appears to be a suitable matrix for non‐invasive CYP3A phenotyping using midazolam as a probe drug, but sensitive analytical methods are required.
The Leader Observation Tool: a process skills treatment fidelity measure for the Incredible Years parenting programme
Authors: Eames C. , Daley D. , Hutchings J. , Hughes J. C. , Jones K. , Martin P. , Bywater T.
Published: April 2008

Background  Despite recognition of the need to deliver evidence‐based programmes in the field of mental health, there is little emphasis on implementing such programmes with fidelity. Attempts by programme developers to ensure adherence to their programmes include the development of training, manuals and content scales, but these alone may be insufficient to ensure fidelity in replication. Observational measures lend themselves as a potentially useful assessment of intervention outcomes, providing accurate and objective accounts of the intervention process.

Aim  To develop a reliable and valid observational treatment fidelity tool of process skills required to deliver the Incredible Years (IY) BASIC parenting programme effectively.

Methods  An objective observational fidelity measure was developed to assess adherence to the IY BASIC parenting programme protocol. Observations were conducted on 12 IY BASIC parenting programme groups, attended by parents of pre‐school children displaying signs of early onset conduct disorder.

Results  The Leader Observation Tool (LOT) achieved high internal reliability and good code–recode and inter‐rater reliability. Evidence of concurrent validity was also obtained.

Conclusions  Having demonstrated that the LOT is a reliable and valid measure of implementation fidelity, further research is necessary to examine the relationship between LOT scores and intervention outcome.
Risk factors for smoking among school adolescents in Greece
Authors: Damianaki A. , Kaklamani S. , Tsirakis S. , Clarke R. , Tzanakis N. , Makris D.
Published: April 2008

Objective  We conducted this study among school adolescents to identify factors, which influence schoolchildren to smoke.

Methods  We carried out a cross‐sectional study in a sample of 924 students of all classes (ages 12–18 years old) in 15 public high schools in a semi‐urban area in Crete, Greece, using a questionnaire. The questionnaire comprised of 46 questions covering children's lifestyle habits regarding daily activities and leisure time, frequency of risk‐taking behaviour, knowledge about the hazards and long‐term consequences of smoking.

Results  23.9% of participants were experimental smokers and 18.6% were current smokers. 11.4% of the total population was daily smokers. There was a significant increase in the prevalence of experimental and current smokers with school grades, while peaks in last grades were observed. Boys started smoking earlier than girls, mean (standard error) age 13.4 (2.3) years vs. 14.1 (2.3) years, P = 0.01. Stepwise logistic regression analysis showed a positive relationship between current smoking and having brother or sister smoking [odds ratio (95% confidence interval) 2.7 (1.7–4.4) and 1.8 (1.1–3.3) respectively], having more than three friends who were smokers [2.6 (2–3.4)] and last school grade [1.4 (1.2–1.7)]. Students appeared to be informed about long‐term smoking hazards and had negative views on children who smoke especially in the lower grades.

Conclusions  Prevention programmes should be imposed early in elementary schools while cessation policies should target at all grades, in particular at critical grades depending on population‐specific characteristics.
Oestrogen metabolites in relation to isoprostanes as a measure of oxidative stress
Authors: Sowers MaryFran , McConnell Daniel , Jannausch Mary L. , Randolph John F. , Brook Robert , Gold Ellen B. , Crawford Sybil , Lasley Bill
Published: April 2008

Objective  Oestradiol (E2) and its metabolites 2‐hydroxyoestrone (2‐OHE1) and 16α‐hydroxyoestrone (16α‐OHE1) are thought to curtail the greater oxidative stress found in the development and progression of disease conditions including atherosclerosis. We related oestrogen levels to F2a‐isoprostane levels, a biomarker of oxidative stress.

Design and participants  Data were obtained from 1647 women, aged 47–57 years, participating in the fifth annual follow‐up of the Study of Women's Health Across the Nation (SWAN), a study of the menopausal transition.

Measurements  Serum E2 and urinary 2‐OHE1 and 16α‐OHE1 concentrations were determined by enzyme‐linked immunosorbent assay (ELISA) and urinary F2a‐isoprostanes were measured by enzyme immunoassay (EIA).

Results  F2a‐isoprostane concentrations were elevated in women who smoked, a behaviour associated with increased oxidative stress, but not in stages of the natural menopause. Mean F2a‐isoprostane concentrations among pre‐ and postmenopausal women who smoked were 1082 and 1064 pg/ml, respectively, values double those in pre‐ (343 pg/ml) and postmenopausal (379 pg/ml) nonsmoking women. 2‐OHE1 and F2a‐isoprostane concentrations were positively and highly correlated (partial correlations ρY|X = 0·44 and ρY|X = 0·43 in pre‐ and postmenopausal women, respectively). Similarly, 16α‐OHE1 concentrations were positively and highly correlated with F2a‐isoprostane concentrations (ρY|X = 0·52 and ρY|X = 0·59 in pre‐ and postmenopausal women, respectively). E2 was significantly correlated with F2a‐isoprostanes only in postmenopausal women (ρY|X = 0·20). Associations were adjusted for age, body mass index (BMI), race/ethnicity, lipids, physical activity level and alcohol consumption.

Conclusions  This study does not support the commonly held hypothesis that levels of endogenous E2 or its oestrone metabolites favourably modify oxidative stress by decreasing F2a‐isoprostane levels.
Depot‐specific steroidogenic gene transcription in human adipose tissue
Authors: MacKenzie Scott M. , Huda Shahzya S. , Sattar Naveed , Fraser Robert , Connell John M. C. , Davies Eleanor
Published: April 2008

Context  Sex steroids (androgens and oestrogens) and corticosteroids (glucocorticoids and mineralocorticoids) have a major impact on fat distribution. Several genes involved in steroid synthesis and metabolism, such as 11β‐hydroxysteroid dehydrogenase type 1 and aromatase, are known to be expressed within adipose tissue, thus modulating local steroid levels; however, our knowledge of which genes are expressed and at what level is incomplete.

Objective  To detect by real‐time quantitative reverse transcriptase polymerase chain reaction (qRT‐PCR) which of 13 key steroidogenic genes are transcribed within human adipose tissue and to assess whether mRNA levels differ significantly between the subcutaneous abdominal and omental adipose depots.

Patients  Eight women undergoing caesarean section [age 29·1 ± 6·5 years, body mass index (BMI) 28·9 ± 8·4 kg/m2].

Results  Genes transcribed in both depots were StAR (steroidogenic acute regulatory protein), CYP11A1 (side‐chain cleavage enzyme), HSD3B2 (3β‐hydroxysteroid dehydrogenase type 2), CYP21B (21‐hydroxylase), CYP19 (aromatase), HSD11B1 (11β‐hydroxysteroid dehydrogenase type 1), HSD17B3, HSD17B5, HSD17B7 (17β‐hydroxysteroid dehydrogenase types 3, 5 and 7) and SRD5A2 (5α‐reductase type 2). All but SRD5A2 varied significantly in abundance between depots. CYP17 (17α‐hydroxylase), CYP11B1 (11β‐hydroxylase) and CYP11B2 (aldosterone synthase) transcription were not detected.

Conclusions  This study confirms and significantly extends our knowledge of steroidogenic gene expression within adipose tissue, showing that transcript levels are depot specific. We have demonstrated that de novo synthesis from cholesterol of sex steroids, cortisol and aldosterone is not possible because of the absence of key steroidogenic mRNAs. Instead, the pattern of transcription suggests that 11‐deoxycorticosterone, a mineralocorticoid, would be the ultimate product of any de novo adipose synthesis.
Correlation of circulating full‐length visfatin (PBEF/NAMPT) with metabolic parameters in subjects with and without diabetes: a cross‐sectional study
Authors: Retnakaran Ravi , Youn Byung‐Soo , Liu Ying , Hanley Anthony J. G. , Lee Nam Seok , Park Ji Woo , Song Eun Sun , Vu Vivian , Kim Wi , Tungtrongchitr Rungsunn , Havel Peter J. , Swarbrick Michael M. , Shaw Collin , Sweeney Gary
Published: April 2008

Objective  Here we use a novel ELISA that is specific for full‐length visfatin (PBEF/NAMPT), compare it with the existing C‐terminal based assay and use it to investigate associations of visfatin with metabolic parameters.

Design, patients and measurements  We established the specificity and effectiveness of the new ELISA and evaluated the associations of full‐length visfatin with clinical, anthropometric and metabolic parameters in a cross‐sectional study of 129 Thai subjects, consisting of 50 outpatients with type 2 diabetes and 79 healthy volunteers.

Results  The new ELISA accurately recovered full‐length recombinant visfatin and detected visfatin secreted by primary human and rat adipocytes. We found serum full‐length visfatin was significantly higher in subjects with diabetes compared to their nondiabetic peers (median 2·75 vs. 2·22 ng/ml, P = 0·0142). After adjustment for age, gender and traditional metabolic risk factors, adjusted mean visfatin remained significantly higher in the diabetes group (3·80 vs. 2·10 ng/ml, P = 0·0021). On Spearman univariate correlation analysis, visfatin was significantly associated with resistin (r = 0·30, P = 0·0011), but not with any other anthropometric or metabolic variables, including adiponectin multimers. On multiple linear regression analysis, the only covariates independently associated with visfatin were diabetes (t = 3·11, P = 0·0024) and log resistin (t = 2·68, P = 0·0086).

Conclusions  Circulating visfatin is independently associated with diabetes and resistin concentration, but is not related to adiponectin multimers or other metabolic covariates. These data are suggestive of a potential role of visfatin in subclinical inflammatory states.
Diagnosis and management of amiodarone‐induced thyrotoxicosis: similarities and differences between North American and European thyroidologists*
Authors: Tanda Maria Laura , Piantanida Eliana , Lai Adriana , Liparulo Luigi , Sassi Lorenza , Bogazzi Fausto , Wiersinga Wilmar M. , Braverman Lewis E. , Martino Enio , Bartalena Luigi
Published: April 2008

Objective  To investigate how North American thyroidologists assess and treat amiodarone‐induced thyrotoxicosis (AIT) and to compare the results with those of the same questionnaire‐based survey previously carried out among European thyroidologists.

Design  Members of the American Thyroid Association (ATA) with clinical interests were sent by e‐mail a questionnaire on the diagnosis and management of AIT, 115 responses were received from the United States and Canada, representing about one‐third of ATA members with clinical interests.

Results  The majority of respondents (91%vs. 68% in Europe, P < 0·05) see < 10 new cases of AIT per year, and AIT seems less frequent than amiodarone‐induced hypothyroidism (AIH) in North America (34% and 66% of amiodarone‐induced thyroid dysfunction, respectively, vs. 75% and 25%, respectively, in Europe, P < 0·001). When AIT is suspected, in North America hormonal assessment is mostly based on serum free T4 (FT4) and TSH measurements, while serum free T3 (FT3) determination is requested less frequently than in Europe; thyroid autoimmunity is included in the initial assessment less than in Europe. Most commonly used additional diagnostic procedures include, as in Europe, thyroid colour‐flow Doppler sonography, and to a lesser extent, thyroid radioactive iodine uptake and scan, but Europeans tend to request multiple tests more than North Americans. Withdrawal of amiodarone is more often considered unnecessary by North American thyroidologists (21%vs. 10% in Europe in type 1 AIT, P < 0·05, 34%vs. 20% in type 2 AIT, P < 0·05). In type 1 AIT thionamides represent the treatment of choice for North Americans as well as for Europeans, but the former use them as monotherapy in 65%vs. 51% of Europeans (P < 0·05) who more often consider potassium perchlorate as an useful addition (31%vs. 15% of North Americans, P < 0·01). Glucocorticoids are the selected treatment for type 2 AIT, alone (62%vs. 46% in Europe, P < 0·05) or in association with thionamides (16%vs. 25% in Europe, P = NS). After restoration of euthyroidism, thyroid ablation in the absence of recurrent thyrotoxicosis is recommended in type 1 AIT less frequently by North Americans. If amiodarone therapy needs to be reinstituted, prophylactic thyroid ablation is advised by 76% in type 1 AIT, while a ‘wait‐and‐see’ strategy is adopted by 61% in type 2 AIT, similar to behaviour of European thyroidologists.

Conclusion  Similarities and differences exist between expert North American and European thyroidologists concerning the diagnosis and management of AIT. While differences reflect the frequent uncertainty of the underlying mechanism leading to AIT, similarities may represent the basis to refine the diagnostic criteria and to improve the therapeutic outcomes of this challenging clinical situation.
Can host‐range allow niche differentiation of invasive polyphagous fruit flies (Diptera: Tephritidae) in La Réunion?
Authors: DUYCK PIERRE‐FRANCOIS , DAVID PATRICE , PAVOINE SANDRINE , QUILICI SERGE
Published: April 2008

Abstract 1. Biological invasions bring together formerly isolated insect taxa and allow the study of ecological interactions between species with no coevolutionary history. Among polyphagous insects, such species may competitively exclude each other unless some form of niche partitioning allows them to coexist.

2. In the present study, we investigate whether the ability to exploit different fruits can increase the likelihood of coexistence of four species of polyphagous Tephritidae, one endemic and three successive invaders, in the island of La Réunion. In the laboratory, we studied the performances of all four species on the four most abundant fruit resources in the island, as well as the relative abundances of fly species on these four fruit species in the field. We observe no indication of niche partitioning for any of the four abundant fruits.

3. Analyses of an extensive field data series suggest that: (i) the four fly species largely overlap in fruit exploitation, once climatic effects are accounted for; (ii) however, one species (Ceratitis capitata) can exploit rare fruit species that are not exploited by others present in the same climatic niche; and (iii) the endemic species C. catoirii, now nearly extinct in La Réunion, has no private niche with respect to either climatic range or fruit use.

4. On the whole, with the possible exception of C. capitata, the results point to a limited role of fruit diversity in encouraging coexistence among polyphagous tephritids recently brought into contact by accidental introductions.
Oxidation‐specific epitopes are important targets of innate immunity
Authors: Chou M.‐Y. , Hartvigsen K. , Hansen L. F. , Fogelstrand L. , Shaw P. X. , Boullier A. , Binder C. J. , Witztum J. L.
Published: April 2008

During the oxidation of LDL, a central pathophysiological component of atherogenesis, a wide variety of chemical and physical changes occur leading to the generation of oxidation‐specific neoepitopes. These epitopes are not only immunogenic, leading to adaptive humoral responses, but are also a prominent target of multiple arcs of innate immunity. The pattern recognition receptors (PRRs) of innate immunity are germ line encoded, conserved by natural selection, and bind to pathogen‐associated molecular patterns (PAMPs) common on multiple structures. However, it is not intuitive as to why they should recognize oxidation‐specific neoepitopes. Yet it is clear that multiple macrophage scavenger receptors, which are classic PRRs, recognize oxidation‐specific epitopes, such as those found on oxidized LDL (OxLDL). Other innate proteins, such as C‐reactive protein, also bind to OxLDL. Natural antibodies (NAbs), the humoral arc of innate immunity, provide a nonredundant role in the first line of defence against pathogens, but are also believed to provide important homeostatic house‐keeping functions against self‐antigens. Our work demonstrates that oxidation‐specific epitopes, as found on OxLDL, are a major target of NAbs. In this review, we will discuss the specific example of the prototypic NAb T15/E06, which is increased in atherosclerotic mice and mediates atheroprotection, and discuss the potential role of NAbs in atherogenesis, and in inflammation in general. We also review data that oxidation‐specific epitopes are generated whenever cells undergo programmed cell death, forming a common set of PAMPs recognized by oxidation‐specific PRRs on macrophages, NAbs and innate proteins. We present the hypothesis that oxidation‐specific epitopes on apoptotic cells exerted evolutionary pressure for the conservation of these PRRs and also serve to maintain the expansion of a substantial proportion of NAbs directed to these stress‐induced self‐antigens.
Palate morphology of bruxist children with mixed dentition. A pilot study
Authors: RESTREPO C. C. , SFORZA C. , COLOMBO A. , PELÁEZ‐VARGAS A. , FERRARIO V. F.
Published: April 2008

Summary  The objective of the study was to analyse quantitatively palatal morphology in bruxist and non‐bruxist children with mixed dentition. Twenty‐three children with mixed dentition were classified as bruxist according to their anxiety level, audible occlusal sounds related by the parents and signs of temporomandibular disorders; 23 children were control subjects matched for gender, age, and dental formula. The maxillary dental arches of all subjects were reproduced from alginate impressions cast in dental stone with a standardized technique. The casts were digitalized and mathematical equations were used to obtain the form of the palate in the sagittal, frontal and horizontal planes. Bruxist children had a statistically significant longer palate in the sagittal plane than control children; palatal shape differed especially in correspondence of the third, fourth and fifth teeth, bruxist children showing a relatively higher palate than control children. In this pilot study, sagittal plane differences in the palate between bruxist and non‐bruxist children matched for age and gender were found. Further investigations are needed to understand better the clinical implications of the findings. Results should be taken into account in the diagnosis of the occlusal development in children with parafunctions to prevent future abnormalities: a bruxist child may have bigger dental arches than a normal child.
Levamisole synergizes proliferation of intestinal IgA+ cells in weaned pigs immunized with vaccine candidate F4ac+ nonenterotoxigenic Escherichia coli strain
Authors: JANJATOVIĆ A. K. , LACKOVIĆ G. , BOŽIĆ F. , POPOVIĆ M. , VALPOTIĆ I.
Published: April 2008

Levamisole (2, 3, 5, 6‐tetrahydro‐6‐phenylimidazole 2,1‐b thiazole) is a well‐known nonspecific stimulator of host defence mechanisms. In previous investigations, we have found that levamisole acts on cell‐mediated immunity in challenge‐induced porcine postweaning colibacillosis (PWC). We assume that levamisole could also act synergistically on humoural immune response when applied as an adjuvant with vaccine candidate strains for oral immunization of weaned pigs against PWC. The influence of levamisole in combination with experimental F4ac+ nonenterotoxigenic Escherichia coli (non‐ETEC) vacinal strain on proliferation of IgA+ cells was examined in 4‐week‐old weaned pigs experimentally infected with ETEC. We have performed identification and morphometric quantification of the plasma cell phenotype within jejunal/ileal mucosa. Plasma cells were identified by immunohistochemistry with monoclonal anti‐IgA antibodies and quantifying by use of digital image analysis. Quantification of IgA+ cells from levamisole‐primed vaccinated and challenge‐infected weaned pigs showed significantly increased number (P < 0.05 for both jejunum and ileum) compared with those observed in unprimed vaccinated/challenge‐infected controls. It is suggested from these results that levamisole may contribute in initiation of local humoural immune response to enteric pathogens, such as enterotoxigenic E. coli.
Patterns of daily activity in mammals
Authors: ASHBY K. R.
Published: April 2008

The adaptation of the various mammals to all gradations between a totally diurnal to a totally nocturnal pattern of activity is noted and the nature of the determinants of the high proportion of species which are crepuscular or nocturnal is discussed. It is seen that detailed study of the activity patterns has been confined to a small proportion of species, principally some of the smaller rodents. Ruminants are unusual in remaining vigilant during normal sleep, loss of awareness of external events being confined to periods of paradoxical sleep which occupy a very small proportion of the 24 hours.

The 24 hour rhythm of activity has an endogenous basis. Under normal conditions it is entrained by the changes in light intensity at dusk and dawn, but circadian activity rhythms can be entrained to periodicities longer or shorter than 24 hours. Relatively small variations in the intensity of the lighting between day and night are effective in maintaining entrainment, but under arctic conditions in summer the 24 hour rhythm becomes much less pronounced and activity may even develop a free–running pattern.

A short–term rhythm with a regular periodicity of a small number of hours has been reported to occur by many authors in species of small eutherian mammals feeding on a bulky diet, that is insectivores and the more herbivorous of the small rodents. A summary account is given of information, much of it derived from unpublished research, indicating that in fact the patterns of diel activity of such rodents vary greatly with the environmental conditions. The duration of daylight is apparently only one of many factors affecting the distribution of their activity over the 24 hours. It is noted that versatility of this nature also occurs in some large mammals.

It is concluded that an advance in knowledge of the mechanisms determining the activity patterns of mammals will require a greater emphasis on field observations of mammal behaviour and on laboratory experiments in which the variety of conditions found in nature is closely simulated.
Circadian physiological rhythms
Authors: MILLS J. N.
Published: April 2008

Mammals show numerous circadian rhythms, some exogenous but nonetheless useful, some endogenous. Even in the absence of exogenous synchronizers, different physiological functions usually preserve their normal temporal relations, suggesting that a single clock controls most or all of the rhythmic manifestations. The role of adrenal corticosteroids and of temperature as means whereby the clock influences other functions is considered.
Survival in wild‐living mice*
Authors: BERRY R. J. , JAKOBSON M. E. , TRIGGS G. S.
Published: April 2008

The survival of a mouse in the wild depends on its reaction to the environment (food, climate, social conditions, cover, disease and predation), and this depends on the condition or ‘vigour’ of the animal itself. In general an animal increases in vigour until adulthood, and then begins to decrease, in House mice, at an age of approximately 100 days. These changes can be described as ageing; they lead to the characteristic U‐shaped mortality curves deduced from life‐tables in a wide variety of mammalian species. Another factor that has to be taken into consideration is genotype, since animals of different genotype may respond differently to environmental stresses. A large number of deaths in wild‐living House mouse populations in Britain are temperature‐dependent. Animals may respond to cold either physiologically or behaviourally, but it is possible to distinguish between winter survivors and non‐survivors with a fair degree of accuracy on the basis of physiological measurements made in the autumn (i.e. before the time of environmental stress). Nevertheless, any general survival model must incorporate environmental, ontogenetic, and genetic factors and their interactions. A simple model is proposed.

Animals are not always struggling for existence. They spend most of their time doing nothing in particular. But when they do begin, they spend the greater part of their lives eating (Charles Elton).
The origin and distribution of feral mink in Scotland
Authors: CUTHBERT J. H.
Published: April 2008

A result of the post‐war boom in mink farming was the escape of mink which are now well established in the wild. Feral mink are known to be present in all Scottish mainland counties, except Sutherland and Caithness, and are also found on the islands of Arran and Lewis. Populations are thriving on most of the main river systems. The existence of suitable habitat and adequate food supplies suggests that mink will continue to increase and spread in Scotland.
Ecology and behaviour of domestic sheep (Ovis aries): a review
Authors: SQUIRES VICTOR R.
Published: April 2008

Behaviour of sheep is complex and poorly understood. It is only within the past 20 years that a concerted effort has been made to elucidate those aspects of behaviour which have most relevance to sheep raising under open‐range conditions.

The present report attempts to summarize and review published work on the behaviour and ecology of sheep.

The whole question of the significance of behaviour and the extent to which it is possible to shape it is a field which is open for study. This paper is an attempt to summarize the work on sheep behaviour and on those aspects of physiology which impinge.

Consideration is given to the evolution of Bovids, scope of domestication and world distribution of sheep since these aspects have a major influence on the sheep with which we deal today. Animal requirements for food, water, shelter, protection from predators, and control of disease and parasites have been largely met by man and the forces for selection which operated among the progenitors of domestic sheep have been largely negated. Despite this, genetic selection still goes on.

Behavioural adaptation to a wide variety of environmental and nutritional regimes is a common feature among free‐ranging sheep. Reproductive success, a matter of considerable commercial concern is often poor. Lamb survival is of critical importance. Factors involved in neonatal mortality are reviewed in detail.

Finally, the now extensive literature on sheep behaviour, physiology and management is collated in a bibliography with over 150 literature citations.
Conservation versus commercial exploitation of seals with special reference to the Harp seal
Authors: PLATT COLIN
Published: April 2008

For the past 15 years at least, government officials, scientists, observers and representatives of the news media have massed each year in the Gulf of St Lawrence, Canada, to witness the killing of Harp seals, Pagophilus groenlandicus, by the commercial sealing industry. This species has become possibly the most studied, the most reported and the most photographed species of wildlife in living memory.

Much of this attention has been directed towards arousing public opinion against the annual seal hunts in the Gulf and in the ‘Front’ areas of the Northwest Atlantic off the coasts of Labrador and Newfoundland. However, considerable scientific research has been done into the behavioural habits and population dynamics of the Harp seal.

Our present knowledge of this species and the co‐operation afforded by the governments of Canada and Norway, enable the Labrador herd of the Harp seal to be used as testing ground for rational herd management based on sound conservation principles. But have we achieved our objective?