bluuebunny/crossref_metadata_2025 huggingface dataset:
Heart Rate Turbulence after Ventricular Pacing Trains During Programmed Ventricular Stimulation
Authors: HAVRANEK STEPAN , STOVICEK PETR , PSENICKA MIROSLAV , WICHTERLE DAN , LINHART ALES
Published: January 2007

Background: This study tested the hypothesis that heart rate turbulence (HRT) following ventricular pacing trains depends on train cycle length, presence of retrograde ventriculoatrial (VA) conduction, and left ventricular (LV) function.

Methods: We analyzed digital recordings of programmed ventricular stimulation (PVS) performed in 82 patients (57 men) referred for electrophysiologic studies of ventricular arrhythmias, whose mean age was 64 ± 12 years and LV ejection fraction (EF) was 47 ± 15%. Profiles of sinus RR intervals after all available 8‐beat ventricular pacing trains (600‐and 400‐ms) were averaged. Heart rate turbulence slope (HRTS) was analyzed as the maximum positive slope of a regression line through a sequence of 2–5 (HRTS2 ‐ HRTS5) consecutive RR intervals within the first 5 RR intervals after the pacing train.

Results: Dynamics of RR intervals had biphasic and monophasic patterns, in patients with and without VA conduction, respectively. Sinus nodal response was less prominent after 600‐ms than 400‐ms pacing trains. After 400‐ms pacing trains, HRTS was significantly shallower in patients with LVEF ≤40% than in those with LVEF >40%. HRTS4 was the best discriminator between the two groups (6.8 ± 8.6 ms/RR vs 19.6 ± 26.0 ms/RR, P = 0.017).

Conclusion: In patients with VA conduction, HRT after ventricular pacing trains reflects a combination of vagal withdrawal due to transient hypotension and suppression of sinus node automaticity. Attenuation of vagal modulation was detected in patients with LV dysfunction during standard PVS.
Heart Rate Turbulence after Atrial Premature Complexes Depends on Coupling Interval and Atrioventricular Nodal Conduction
Authors: WICHTERLE DAN , BULKOVA VERONIKA , FIKAR MIROSLAV , HAVRANEK STEPAN , STOVICEK PETR
Published: January 2007

Background: Positive Turbulence onset (TO) after atrial premature complexes (APCs) was found temporally related to spontaneous episodes of atrial fibrillation. This study tested the hypothesis that heart rate turbulence (HRT) after APCs is influenced by APC prematurity independently of the prematurity of conducted ventricular complexes.

Methods: We studied 33 patients (mean age = 58 ± 16 years, 19 men), 11 of whom had structural heart disease, who were referred for electrophysiological studies of supraventricular or ventricular arrhythmias. Sequences of single right atrial extrastimuli were delivered with coupling intervals adjusted to reach 60% prematurity of conducted ventricular complexes. Descriptors of HRT were compared between patients with slow versus fast atrioventricular (AV) conduction of APCs.

Results: The early RR interval dynamics after APCs was prominently modulated by the suppression of sinus node automaticity by the direct effect of APCs. This effect was significantly greater after earlier APCs with longer AV conduction times than after later coupled APCs with shorter AV conduction times.

Conclusions: The early phase of HRT is strongly influenced by the coupling interval of APCs, independently of the prematurity of conducted ventricular complexes. Consequently, the more positive TO preceding spontaneous atrial fibrillation episodes might be an epiphenomenon of incidental short‐coupled APCs with delayed AV conduction, likely to trigger atrial fibrillation.
Ventricular Repolarization Dynamics During Different Sleep Stages in the Subacute Phase of Myocardial Infarction
Authors: BONNEMEIER HENDRIK , NÖTGES JANA K. , MAJUNKE BENINA , STRASSBURG ALAN , ORTAK JASMIN , KOTHE HENNING , WEITZ GUNTHER , SCHUNKERT HERIBERT
Published: January 2007

Background: Ventricular arrhythmias after myocardial infarction (MI) are often nocturnal. However, the arrhythmogenic effects of sleep after MI are unknown. We examined the effects of sleep stages on QT dynamicity and tested the hypothesis of a differential effect of sleep stage on the QT/RR relationship after recent MI, versus in healthy controls (HC).

Methods: Polysomnography and electrocardiograms were simultaneously recorded in 21 men in the subacute phase of a first uncomplicated MI, and in 10 age‐matched, male HC. QT dynamicity (QT/RR slope) and parameters of QT interval were measured during wakefulness, stages 1–4 of nonrapid eye movement (non‐REM) sleep, and REM sleep.

Results: Mean QT and RR intervals increased through all sleep stages in both MI survivors and HC. The Bazett‐corrected QT interval remained stable from wakefulness throughout all sleep stages. QT/RR slopes remained stable from wakefulness to stage 3 in both groups. However, unlike in MI survivors, the QT/RR slopes decreased and remained significantly lower during deep sleep and REM sleep in HC.

Conclusion: An abnormal QT/RR relationship in deep sleep and REM sleep was observed after a recent MI, reflecting an insufficient shortening of ventricular repolarization with increasing heart rates, which might have important implications in the nocturnal distribution of ventricular arrhythmias after MI.
Effects of Aging on Reflex Autonomic Nervous Response Induced by Orthostatic Maneuvers
Authors: BARANTKE MELANIE , ORTAK JASMIN , LIEB WOLFGANG , WILKE IRIS K. , SCHUNKERT HERIBERT , BONNEMEIER HENDRIK
Published: January 2007

Background: Baroreflex sensitivity (BRS), exercise pressor reflex (EPR), and aging influence the autonomic nervous response associated with orthostatic maneuvers. Standing significantly increases heart rate (HR), with an initial increase (1.ΔHR) due to EPR and a secondary, more gradual increase (2.ΔHR) due to BRS. HR then decreases (3.ΔHR), which is also attributable to BRS. Thus far, however, few data are available regarding the interdependence of these variables.

Methods and Results: Ninety‐five healthy volunteers (mean age 37 ± 11 years, range 10–70 years; 50 women) underwent continuous noninvasive measurements of beat‐to‐beat blood pressure, HR, and spontaneous BRS in the supine (10 minutes) and upright (10 minutes) positions. After tilt, 1.ΔHR, 2.ΔHR, and 3.ΔHR were calculated from the HR recording. From the 1st to the 6th decade BRS, 2.ΔHR and 3.ΔHR decreased with normal aging ([BRS 11.88 ± 7.97 ms/mmHg to 1.81 ms/mmHg, P = 0.006], 2.ΔHR [16.75 ± 3.40 beats to 5.33 ± 2.52 beats, P = 0.002], 3.ΔHR [52.25 ± 5.91 beats to 11.33 ± 4.04 beats, P < 0.001]). However, no such association was noted between 1.ΔHR and age (21.25 ± 9.35 beats to 12.00 ± 7.21 beats, ns). BRS while standing was correlated with 1.ΔHR (r = 0.432, P < 0.001).

Conclusions: EPR, in contrast to BRS, was not significantly influenced by normal aging. Furthermore, not only was BRS influenced by EPR, as is generally acknowledged, but EPR and BRS were interrelated. These observations offer new insights into the complex interactions of orthostasis‐induced physiological autonomic reflexes associated with normal aging.
Modulation of Cardiac Autonomic Nervous Activity Early after Cardioversion of Atrial Fibrillation by Biphasic Waveform
Authors: ORTAK JASMIN , KURTZ FRANZISKA , KRENZIEN ANN‐SOPHIE , JANCA NINA , WILKE IRIS , BARANTKE MELANIE , EBERHARDT FRANK , WIEGAND UWE K.H. , SCHUNKERT HERIBERT , BONNEMEIER HENDRIK
Published: January 2007

Background: Imbalance of cardiac autonomic nervous modulation might prominently contribute to early relapses of atrial fibrillation (AF) after cardioversion (CV). The biphasic (Bi) waveform is more effective than the monophasic (Mo) waveform in CV of AF. Whether these waveforms have different effects on autonomic modulation early after CV is unknown.

Methods: We investigated 171 consecutive patients after successful electrical CV (mean age 65.4 years, 82% male, 80% structural heart disease). Bi waveform was used in 89, Mo waveform in 82. Heart rate variability (HRV) was analyzed from 24‐hour Holter recordings, started directly after CV.

Results: Mean delivered total energy was significantly lower in the Bi group (Bi 223 ± 163 W, Mo 355 ± 211 W, P < 0.001). Mean RR interval decreased within 5 hours after CV and increased again within the remaining hours, without significant differences between Bi and Mo groups. Time courses of time domain parameters of HRV revealed Bi profiles with the lowest levels 6 hours after CV in both groups. However, the hourly values of HRV were significantly higher in the Bi subgroup.

Conclusion: Our study indicates that waveform and total delivered energy significantly influence autonomic modulation of the sinus node in the early phase after CV of AF. In contrast to Bi CV, Mo CV is characterized by a significant decrease of cardiac vagal modulation, which may have an arrhythmic effect by increasing the degree of early electrical stunning after CV of AF.
Lead Design and Initial Applications of a New Lead for Long‐Term Endovascular Vagal Stimulation
Authors: NABUTOVSKY YELENA , FLORIO JOSEPH , MORGAN KEVIN , GRILL WARREN M. , FARAZI TARANEH G.
Published: January 2007

Background: Vagal nerve stimulation (VNS) has negative chronotropic and dromotropic effects. We developed and tested an endovascular spiral vagal stimulation lead (ESVL) designed to follow the projection of the cardiac branches of the vagus nerve around the superior vena cava (SVC) to optimize VNS.

Methods: ESVL contained six 5‐mm coil electrodes, spaced 5‐mm apart with a spiral guidewire to provide shape. The tightness and diameter of the guidewire were changed before each placement to simulate different lead designs. Various 2‐, 3‐, and 4‐electrode combinations were used and several lead positions were tested each time. Each VNS protocol included 2–12 V, 15‐second pulse trains at 20 Hz, with 2 ms pulse duration. A basket catheter (BC) was used as control and to approximate the initial VNS location. The VNS protocol was performed at the optimal location, using first the BC and then several ESVL configurations.

Results: VNS caused a voltage‐dependent decrease in heart rate (HR). Using the optimal ESVL configuration at 7 V, HR decreased by 30.4% (37.2 bpm) in dog no. 1 and 12.4% (16.6 bpm) in dog no. 2, versus 15.5% (16.6 bpm) and 16.7% (19.5 bpm) with the BC.

Conclusions: A new endovascular spiral lead that takes advantage of the anatomy of the cardiac branches of the vagus nerve in the SVC was developed. VNS using ESVL produced significant HR slowing at voltages slightly below the highest pulse generator output of 7.5 V, which may be suitable for long‐term implantation.
Markets and pro‐poor agricultural growth: insights from livelihood and informal rural economy models in Malawi
Authors: Dorward Andrew
Published: January 2007

This article presents the development of a set of programming models describing the major features of different rural livelihoods and of the informal rural economy they together make up in Malawi. The models allow for differentiated responses by different household types to change and for the partial equilibrium effects of consequent supply, demand, and price adjustments in labor and grain markets. The models provide insights into the relations between own‐farm and nonown‐farm activities in different households' livelihoods and in the informal rural economy as a whole, and are used to investigate possible impacts of increasing cash crop prices and of a more open rural economy. Impacts of these changes on the poor are found to be critically dependent upon supply and demand elasticities in labor and grain markets, but the poor could potentially suffer significant losses from increased openness of the local economy leading to increased expenditure by less poor households on imported goods and services.
Economic versus environmental improvement potentials of Danish pig farms
Authors: Asmild Mette , Hougaard Jens Leth
Published: January 2007

This article demonstrates how economic and environmental improvement potentials of Danish pig farms can be estimated using Data envelopment analysis (DEA). To avoid some of the problems associated with the definition of undesirable outputs, environmental variables are included as nutrients applied with manure and nutrients removed with the crops. These environmental variables are combined with a series of economic variables, including the costs of fertilizer. Furthermore, subvector efficiency and a two‐step analysis are used in order to consider economic and environmental (technical) efficiency separately. The empirical results show considerable improvement potentials, especially on the environmental variables. Sensitivity studies validate that these results are robust to possible uncertainties in the measurement of the environmental variables.
Farmer‐to‐farmer technology diffusion and yield variation among adopters: the case of improved cowpea in northern Nigeria
Authors: Alene Arega D. , Manyong V. M.
Published: January 2007

This article examines the magnitude and sources of yield variation among adopters of improved cowpea varieties in northern Nigeria promoted through farmer‐to‐farmer diffusion. The results reveal important efficiency differences between the lead farmers who have contacts with breeders and the follower farmers who get technology and information from the lead farmers. Differential adoption of the package of seed, insecticide, fertilizer, and recommended cereal‐cowpea cropping pattern provides much of the explanation for yield variation among adopters. The component often missing, and hence accounting for much of the yield variation, is the crop management technology relating to the cereal‐cowpea cropping pattern. No efficiency variation is attributed to the source of technology and information, such as whether improved cowpea was obtained from breeders or lead farmers. Technology source has a rather indirect influence on efficiency through its effect on package adoption where breeders promote greater package adoption among the lead farmers than the lead farmers do among the follower farmers. Possible ways of disseminating crop management technological information through the farmer‐to‐farmer technology diffusion are recommended to better exploit the yield and profitability potentials of improved cowpea varieties in northern Nigeria.
Outsourcing and efficiency: the case of Spanish citrus farming
Authors: Picazo‐Tadeo Andrés J. , Reig‐Martínez Ernest
Published: January 2007

Outsourcing in agriculture has traditionally been seen as a managerial strategy of smaller farms to achieve higher levels of efficiency. In this article, we provide empirical evidence supporting the existence of a positive relationship between outsourcing and efficiency in Spanish citrus farming. Outsourcing is measured by the proportion of outsourced labor and capital in farms' total use of these production factors, i.e., the higher the proportion of outsourced inputs, the higher the degree of outsourcing. Making use of data envelopment analysis techniques, we compute input‐specific reductions required to achieve technical efficiency at the farm level. Our results show that attainment of technical efficiency leads to a reduction in the use of both farms' own and outsourced production factors. Furthermore, the degree of outsourcing increases as farms move to their technically efficient productive plans. In addition, outsourcing labor and capital allows farms to achieve efficiency regardless of their size. In our view, this result has a clear implication for policy makers. Instead of trying to improve Spanish citrus farms' competitiveness by pursuing an increase of their average size, policy measures should be adopted to enhance farmers' managerial skills and the efficiency of those external service firms and co‐operatives that are effectively performing basic cultivation tasks.
Ranking efficiency units in DEA using bootstrapping an applied analysis for Slovenian farm data
Authors: Gocht Alexander , Balcombe Kelvin
Published: January 2007

This article explores how data envelopment analysis (DEA), along with a smoothed bootstrap method, can be used in applied analysis to obtain more reliable efficiency rankings for farms. The main focus is the smoothed homogeneous bootstrap procedure introduced by Simar and Wilson (1998) to implement statistical inference for the original efficiency point estimates. Two main model specifications, constant and variable returns to scale, are investigated along with various choices regarding data aggregation. The coefficient of separation (CoS), a statistic that indicates the degree of statistical differentiation within the sample, is used to demonstrate the findings. The CoS suggests a substantive dependency of the results on the methodology and assumptions employed. Accordingly, some observations are made on how to conduct DEA in order to get more reliable efficiency rankings, depending on the purpose for which they are to be used. In addition, attention is drawn to the ability of the SLICE MODEL, implemented in GAMS, to enable researchers to overcome the computational burdens of conducting DEA (with bootstrapping).
Cash crop liberalization and poverty alleviation in Africa: evidence from Malawi
Authors: Masanjala Winford H.
Published: January 2007

This article uses the case of burley tobacco liberalization in Malawi to investigate the efficacy of cash crop liberalization as an instrument for poverty alleviation in sub‐Saharan Africa. The principal justification for cash crop liberalization is that markets allow farm households to increase their incomes by producing that which provides the highest return to their productive resources and use the cash to buy consumption goods. Using a latent welfare model, we find that households that selected to grow cash crops had higher incomes than those that did not grow cash crops. However, we also find that due to the lumpiness and seasonality of cash crop incomes, higher household incomes, while increasing food purchases did not significantly affect per capita food intake. Irrespective of participation in cash crops, for much of the cropping season rural households seem to rely more on nonfarm income for expenditure and consumption smoothing.
Polymorphisms of TLR4 but not CD14 are associated with a decreased risk of aggressive periodontitis
Authors: James Jacqueline A. , Poulton Kay V. , Haworth Simone E. , Payne Debbie , McKay Ian J. , Clarke Fiona M. , Hughes Francis J. , Linden Gerard J.
Published: January 2007

Objective: To study whether there is an association between the frequency of functional polymorphisms in the toll‐like receptor 4 (TLR4) and cluster differentiation 14 (CD14) genes and periodontitis.

Methodology: Genotyping for the TLR4 single‐nucleotide polymorphisms (SNPs) Asp299Gly, Thr399Ile and the CD14 SNPs −159 and −1359 was completed for subjects with periodontal disease compared with control subjects. Two disease populations were investigated: 73 subjects with aggressive periodontitis (AgP; 28 males, 45 females) and 95 males with chronic periodontitis (CP). The TLR4 and CD14 polymorphisms were determined using SNaPshot primer extension with capillary electrophoresis. Comparison of allele and genotype frequencies for each polymorphism was by Fisher's exact test or χ2 analysis.

Results: The TLR4 Asp299Gly genotype was present in a significantly (p=0.026) lower proportion of AgP subjects (5.5%) compared with control subjects (16.3%). The unadjusted odds ratio for the Asp299Gly genotype to be associated with AgP was 0.30, 95% confidence interval 0.10–0.91. No differences were found in the prevalence of the TLR4 Asp299Gly genotype in men with CP (18.9%) compared with an age‐matched control group with no evidence of periodontitis (17%). In addition, there was no difference in the distribution of the CD14 polymorphisms in either the AgP or CP populations studied compared with controls.

Conclusion: It is concluded that in West European Caucasians, the Asp299Gly TLR4 gene polymorphism is associated with a decreased risk of AgP but not CP. Promoter polymorphisms of the CD14 gene, however, did not influence susceptibility to inflammatory periodontitis in the population cohorts studied.
Effect of local antimicrobial agents on excisional palatal wound healing: a clinical and histomorphometric study in rats
Authors: Kozlovsky Avital , Artzi Zvi , Hirshberg Avraham , Israeli‐Tobias Chen , Reich Liat
Published: January 2007

Aim: To assess the effect of topically applied antimicrobial agents on palatal excisional wound in rats.

Materials and Methods: Excisional wounds, 5 mm in diameter, were made in the centre of the palate of 125 Wistar male rats. In four experimental groups, chlorhexidine digluconate (CHX) 0.12% solution, 1% CHX gel, phenolic compounds solution (Listerine®), amine/stannous fluoride solution (Meridol®) and saline solution as a control group were applied daily for 1 min. The wound area was measured photographically and the epithelialization rate was determined histologically at 3, 7, 14 and 21 days post‐surgery.

Results: The mean wound area and mean distance between the epithelial margins decreased significantly with time (p<0.001) in experimental and control groups, with the greatest wound area reduction and rate of epithelialization on day 14. A significantly superior rate of wound epithelialization (p=0.03) was presented following use of 1% CHX gel and Listerine® and a comparatively inferior one when the Meridol® solution was applied.

Conclusions: Each tested antimicrobial agent when applied on an excisional wound with epithelial and connective tissue deficiency did not have a negative effect on the rate of wound closure. The best results were achieved with 1%CHX gel and Listerine®.
Contact sensitization in patients with chronic venous leg ulcers in Singapore
Authors: Lim Kar‐Seng , Tang Mark Boon Yang , Goon Anthony Teik Jin , Leow Yung Hian
Published: January 2007

Contact sensitization rates are high in patients with chronic venous leg ulcers. Allergic contact dermatitis poses a significant hindrance to the healing of the wounds. There are no published studies examining the rate of contact sensitization in Asian patients. Our objective was to determine the rate of contact sensitization in patients with chronic venous leg ulcer in Singapore and the variation in the common allergens based on local practices in comparison with Western countries. 44 patients were patch tested to the National Skin Centre standard series, steroid series, medicaments, topical Chinese medicaments, and to modern wound dressings used. The overall rate of contact sensitization was 61.4%. The common allergen groups were topical antibiotics (18.2%) and topical traditional Chinese medicaments (TTCM) (15.9%). Individually, colophony (11.3%), Saw Hong Choon skin ointment (Kam Bo Med, Hong Kong, Hong Kong) (11.3%), Balsam of Peru (9.1%), and povidone iodine (9.1%) were among the most frequent allergens. The sensitization rate among users of TTCM was notably high (41%). A high rate of contact sensitization was found in our study, similar to previous reports from the West. TTCM play a major role as possible allergens in our patients. In Asian patients, a history of its usage should be elicited, and patch testing should include the commonly used TTCM where possible.
Occupational contact dermatitis to a limonene‐based solvent in a histopathology technician
Authors: Foti Caterina , Zambonin Carlo G. , Conserva Anna , Casulli Claudia , D’Accolti Lucia , Angelini Gianni
Published: January 2007

Recently, D‐limonene‐based solvents are used as a safe alternative to xylene for histological and cytological application to dissolve paraffin. We report the case of a histopathology technician with a recalcitrant hand contact dermatitis strictly related to the use of a limonene‐based solvent agent. Patch tests with SIDAPA (Italian Society of Allergological, Professional and Environmental Dermatology) standard series, limonene‐based solvent used by the patient and D‐ and L‐limonene (both oxidized and nonoxidized form) and with Giemsa and methylene blue stains were performed. Patch testing gave positive results to oxidized D‐ and L‐limonene. The patient retired from work and promptly improved and healed the hand eczema. Subsequently, the potential occurrence of limonene oxidation products in the incriminated preparation was investigated using gas chromatography–mass spectrometry. While patch test showed positive reaction to oxidized limonene, chemical analysis failed to detect oxidized limonene in the preparations used by the patient. Considering the strict relation between the use of the preparations and the appearance of symptoms, we can assume that oxidized limonene may be produced during the handling of limonene‐based products, especially in the presence of oxidants stains, frequently used in histological laboratories.
Occupational allergic contact dermatitis from azithromycin in pharmaceutical workers: a case series
Authors: Milković‐Kraus Sanja , Macan Jelena , Kanceljak‐Macan Božica
Published: January 2007

Background:  Reports on hypersensitivity reactions to azithromycin associated with therapy or occupational exposure have been rare.

Objectives:  A case series describing clinical characteristics, diagnostic pathways and risk factors in occupational allergic contact dermatitis (ACD) caused by azithromycin in pharmaceutical workers is presented.

Patients/Methods:  7 out of 21 pharmaceutical workers exposed to powdered intermediate and final substances in azithromycin synthesis were referred with workplace‐related skin and respiratory symptoms. They all underwent diagnostic procedure involving medical history and examination, patch testing with standard allergens and azithromycin, prick testing with inhalatory allergens and total immunoglobulin E measurement.

Results:  Airborne ACD caused by azithromycin was established in 4 examined workers with positive patch test to azithromycin. 2 workers additionally had positive patch test to intermediate substances. Occupation‐related symptoms of urticaria, rhinoconjunctivitis, laryngitis and/or dyspnoea were described in additional 2 workers without clearly positive patch test to azithromycin. 2 atopic workers had a shorter asymptomatic period between the beginning of the exposure to azithromycin and occurrence of skin symptoms than non‐atopics (2–3 months versus 1–3 years, respectively).

Conclusions:  Our results suggest that daily manipulation with powdered azithromycin and intermediates is a main route of sensitization. Besides contact sensitization, other possible workplace‐related azithromycin hypersensitivity reactions are indicated.
Late reactions in patch tests: a 4‐year review from a clinic of occupational dermatology
Authors: Aalto‐Korte Kristiina , Alanko Kristiina , Kuuliala Outi , Jolanki Riitta
Published: January 2007

Late patch test reactions on day (D) 10–14, which on subsequent retesting appear in the normal time schedule on D2–D4, indicate active sensitization due to the patch test. The objective of this study was to report our series of late patch test reactions.We analysed the clinical records of all the patients who had reported late reactions for the date of the late reaction, the results of the first patch tests and retesting. Between January 2002 and February 2006, we had a total of 16 patients with late reactions (≥D10). 12 of them were retested. Retesting confirmed active sensitization to 1 or more allergens in 11 patients (1.3% of 884 patients patch tested). In these 11 cases, none of the late reactions had clear relevance to the symptoms before its appearance. The commonest allergens were paraphenylenediamine (PPD) in 6 patients (0.72% of 826 PPD tests), elecampane (Inula helenium) and black‐eyed Susan (Rudbeckia sp. hybr.) extracts in 3 patients, and 4‐aminoazobenzene and Disperse Orange 3 in 2 patients. The late reaction did not generally affect the clinical course. Only 1 patient developed new dermatitis possibly due to active sensitization. Late reactions meeting the classic criteria of active sensitization were relatively common in our series from a special clinic of occupational dermatology.
The use of ethanol:diethylphthalate as a vehicle for the local lymph node assay
Authors: Betts Catherine J. , Beresford L. , Dearman R. J. , Lalko J. , Api A. P. , Kimber I.
Published: January 2007

The murine local lymph node assay (LLNA) is used for the prospective identification of contact allergens. This method is not only accepted as a stand‐alone test for the identification of contact allergenic hazard but also used increasingly for the measurement of the relative potency of skin‐sensitizing chemicals as an integral component of the risk assessment process. During the development and validation phases of the method, a list of standard vehicles for use in the LLNA was identified, among them being the vehicle most commonly used acetone/olive oil (4:1, AOO). We have now explored the performance in the LLNA of a non‐standard vehicle, ethanol:diethyl phthalate (1:3, EtOH:DEP), that is used frequently to evaluate dermal effects of fragrance materials in both human and experimental studies. Current investigations have demonstrated that EtOH:DEP induces similar levels of background proliferative responses in lymph nodes comparable with the standard vehicle AOO. Moreover, expected levels of activity are observed when EtOH:DEP is used to deliver a known contact allergen in the LLNA. The conclusion drawn is that EtOH:DEP provides a suitable vehicle for use in the LLNA and that the approach described provides a basis for future evaluation of novel vehicles.
Allergic contact dermatitis to nickel: modified in vitro test protocols for better detection of allergen‐specific response
Authors: Spiewak Radoslaw , Moed Heleen , Von Blomberg Brigitta Mary E. , Bruynzeel Derk P. , Scheper Rik J. , Gibbs Susan , Rustemeyer Thomas
Published: January 2007

To date, no in vitro test is suitable for routine diagnosis of contact allergy. The aim of our study was to establish improved in vitro test protocol for the detection of antigen‐specific responses of lymphocytes from patients with allergic contact dermatitis to nickel (Ni‐ACD). Blood leucocytes from 14 Ni‐ACD patients and 14 controls were cultured in the presence of ‘cytokine cocktails’ skewing lymphocytes towards ‘type 1’ [interferon‐γ (IFN‐γ)‐secreting] or ‘type 2’ [interleukin (IL)‐5 and IL‐13‐secreting] phenotypes. The cocktails consisted of IL‐7 and, respectively, either IL‐12 or IL‐4. Cell responses to nickel were measured with enzyme‐linked immunospot assay (ELISpot), enzyme‐linked immunosorbent assay (ELISA), and lymphocyte proliferation test (LPT). Significant differences between patients with Ni‐ACD and controls were found for the ‘type 2’ cytokines IL‐13 and IL‐5, with further increase of allergen‐specific responses occurring when cultures were supplemented with IL‐7 and IL‐4. No significant differences were found for IFN‐γ. The best correlate to clinical diagnosis was LPT with ‘type 2’ skewing (r= 0.739, P < 0.001), followed by IL‐13 ELISpot with ‘type 2’ skewing (r= 0.654, P < 0.001). The non‐radioactive method that correlated best with LPT was IL‐2 ELISpot (r= 0.809, P < 0.001). Overall, we conclude that combining ELISpot assay with proposed modifications of culture conditions improves detection of specific lymphocyte responses in contact allergy to nickel.
Role of novel targeted agents in the treatment of metastatic colorectal cancer
Authors: DAMIANOVICH Dragan , TEBBUTT Niall C
Published: January 2007

Modern chemotherapy regimens, combining bolus or infused schedules of 5‐fluorouracil (5‐FU) with irinotecan or oxaliplatin, have significantly improved the treatment outcomes of patients with metastatic colorectal cancer (CRC). The addition of novel targeted agents to chemotherapy has the potential to increase the median survival of patients with metastatic CRC beyond 2 years. Bevacizumab, a monoclonal antibody (mAb) to vascular endothelial growth factor, has an established role in first‐line treatment in combination with either 5‐FU/leucovorin or irinotecan/5‐FU/leucovorin regimens, while cetuximab, a mAb to epidermal growth factor receptor, in combination with irinotecan is more suitable for the treatment of refractory metastatic CRC. The use of bevacizumab in later stages of the disease and cetuximab in chemotherapy‐naive patients as well as concurrent treatment with both agents is still under investigation. The landmark studies leading to the approval of these agents in the treatment of metastatic CRC as well as associated toxicity profiles and detailed treatment recommendations are discussed in this review.
Phenology of Plumeria alba and its Herbivores in a Tropical Dry Forest
Authors: Sloan Steven A. , Zimmerman Jess K. , Sabat Alberto M.
Published: January 2007

Understanding phenology in plant populations requires distinction between proximate mechanisms and ultimate (evolutionary) causation. Leaf production and abscission, flower production, and herbivory were monitored for 2 yr in a population of the stem succulent tree, Plumeria alba L. in the Guánica State Forest in southwest Puerto Rico. Dependence of phenological events on abiotic (rainfall and day length) and biotic factors (herbivore abundance/damage) was quantified to discern potential relationships. Leaf flush and flowering were not associated with periods of highest rainfall as might be expected in a dry tropical forest. Rather, these events were highly correlated with day length. We observed that most leaf flush began in March and April, which was several months before the wettest period of the year (August to November). This result is consistent with other studies that show that leaf flush in Plumeria is under photoperiodic control and that the plants initiate growth and reproduction when cloudiness is low and seasonal light availability is greatest. Herbivore damage by caterpillars of the sphinx moth Pseudosphinx tetrio is restricted primarily to the wettest season, consistent with the hypothesis that early leaf flush and reproduction has been selected to avoid herbivory. It is not clear whether photoperiodic control of leaf flush and reproduction serves to maximize seasonal light availability, minimize the impact of herbivores, or both. However, it is clear that peak rainfall is not likely to have been the sole selective factor determining leaf flush and flowering in P. alba.
ISOLATION AND PARTIAL CHARACTERIZATION OF A NOVEL BACTERIOCIN PRODUCED BY LACTOCOCCUS LACTIS SSP. LACTIS MC38
Authors: TÜKEL ÇAĞLA , AVŞAROĞLU M. DILEK , ŞİMŞEK ÖMER , AKÇELİK MUSTAFA
Published: January 2007

This work presents the isolation and partial characterization of a new lactococcal bacteriocin produced by Lactococcus lactis ssp. lactis MC38. The bacteriocin demonstrated broad spectrum of inhibition activity against both pathogenic and food spoilage organisms, and various lactic acid bacteria. This antimicrobial substance appeared to be proteinaceous because its activity was completely inactivated by proteinase K and α‐chymotrypsin. It was heat and pH stable. The apparent molecular mass of the purified bacteriocin, determined by sodium dodecyl sulfate–polyacrylamide gel electrophoresis, was 8.0 kDa. The amino acid composition of the studied bacteriocin was found to be quite different from known lactococcal bacteriocins. The calculation of the number of amino acid residues in the bacteriocin molecule revealed that it contained 62 amino acids.
VIRULENCE LEVELS OF BIOFILM‐GROWN LISTERIA MONOCYTOGENES LO28 ARE LOWER THAN THOSE OF PLANKTONIC CELLS IN AN ORAL INOCULATION TEST ON MICE
Authors: ZUNDEL ETIENNE , GALLOIS YVES , CONSTANTY EMMANUEL , ROCHE SYLVIE M. , MOMPART FLORENCE , MEYLHEUC THIERRY , PARDON PIERRE
Published: January 2007

The aim of this study was to produce Listeria monocytogenes biofilms suitable for virulence assays and to determine whether the released bacteria had the same virulence potential as their planktonic counterparts. Biofilms of Listeria monocytogenes LO28 strain, with or without Sphingomonas paucimobilis CCL10 strain, containing up to 7 log10 cfu/cm2 were produced in polypropylene syringes. The virulence of strain LO28 was analyzed in mice after intravenous, subcutaneous and oral inoculation. Its virulence level in binary cultures was not significantly different from that of monocultures. L. monocytogenes LO28 virulence in biofilms was lower than that of their planktonic counterparts after oral inoculation. Our results suggest that biofilms pose no greater health risk to the consumer than planktonic bacteria.
Calibration of Base Flow Separation Methods with Streamflow Conductivity
Authors: Stewart Mark , Cimino Joseph , Ross Mark
Published: January 2007

The conductivity mass‐balance (CMB) method can be used to calibrate analytical base flow separation methods. The principal CMB assumptions are base flow conductivity is equal to streamflow conductivity at lowest flows, runoff conductivity is equal to streamflow conductivity at highest flows, and base flow and runoff conductivities are assumed to be constants over the period of record. To test the CMB assumptions, fluid conductivities of ground water, surface runoff, and streamflow were measured during wet and dry conditions in a 12‐km2 stream basin. Ground water conductivities at wells varied an average of 6% from dry to wet conditions, while stream conductivities varied 58%. Shallow ground water conductivity varied significantly with distance from the stream, with lowest conductivities of 87 μS/cm near the divide, a maximum of 520 μS/cm 59 m from the stream, and 215 μS/cm 22 m from the stream. Runoff conductivities measured in three rain events remained nearly constant, with lower conductivities of 35 μS/cm near the divide and 50 μS/cm near the stream. The CMB method was applied to the records from 10 USGS stream‐gauging stations in Texas, Kentucky, Georgia, and Florida to calibrate the USGS base flow separation technique, HYSEP, by varying the time parameter 2N*. There is a statistically significant relationship between basin areas and calibrated values of 2N*, expressed as N = 0.46A0.44, with N in days and A in km2. The widely accepted relationship N = 0.83A0.2 is not valid for these basins. Other analytic methods can also be calibrated with the CMB method.
The employment contract and unfair contracts legislation
Authors: Brodie Douglas
Published: January 2007

In 2005, the Law Commissions published a report reviewing unfair contracts legislation in the UK. Where the contract of employment was concerned, the Commissions were of the view that, in short, the status quo should remain. This paper seeks to appraise that position and considers whether an opportunity to bring forward beneficial reforms has been missed. The paper takes cognisance of the legislative scheme in New South Wales, which contains extensive powers where unfair contracts are concerned. It is suggested that, in the UK, the two key issues which need to be addressed are contracting-out and terms which may be substantively unfair.
Breach of contract and the expectation deficit: inconvenience and disappointment
Authors: Chandler Adrian , Devenney James
Published: January 2007

One of the most controversial aspects of the assessment of damages for breach of contract is the extent to which there can be recovery for ‘intangible’ losses such as disappointment and inconvenience. In Watts v Morrow, Bingham LJ assumed that public policy generally proscribed contractual liability for such losses, unless the object of the contract was to provide pleasure and/or peace of mind, or the breach caused foreseeable physical inconvenience to the victim. Unfortunately, Watts, and its associated case-law, offered scant guidance on the underlying rationale for either the general rule or its two exceptions. Consequently, more recent judicial pronouncements on this issue, particularly from the House of Lords, are to be welcomed insofar as they demonstrate a greater preparedness to eschew the use of arbitrary policy constraints in favour of focusing upon a claimant’s expected benefits as contained within the contract. In so doing, disappointment and inconvenience appear to be subject to the same rules of recovery. This paper will seek to justify and encourage this trend, arguing that a logical application of the principles contained within Hadley v Baxendale and Robinson v Harman dispenses with any need to use ‘policy’ as a means of limiting the recovery of damages for disappointment and inconvenience, more properly takes account of a claimant’s known preferences, and ensures that all forms of inconvenience and disappointment are subject to the same rules; in short, that damages properly reflect the full range of the claimant’s expectation deficit.
Ignoring the moral and intellectual shape of the law after Bland: the unintended side-effect of a sorry compromise
Authors: Coggon John
Published: January 2007

In this paper, I explore the sanctity of life doctrine and consider the scope of s 4(5) of the Mental Capacity Act 2005, a provision designed to give statutory effect to the sanctity principle. Rather than question the intellectual validity of the doctrine, I examine the legal and practical problems created by this limited section. I argue that it necessarily creates dilemmas for medical practitioners, which could only be avoided by a wholesale adoption of the principle. I conclude, therefore, that the provision fails to ensure a coherent moral and intellectual shape to the law.
The Gendered Classroom: Girls' and Boys' Experiences in Postwar Germany
Authors: Blessing Benita
Published: January 2007

At the end of World War II, German educational administrators in the Soviet occupied zone of their nation decided to implement coeducation; that is, the schooling of girls and boys in the same classroom. This policy represented a radical break with German educational traditions, as well as with the western German zones' continued practice of gender-segregated schools. The reason for this move was as simple as it was ambitious: educational reformers of the Soviet zone were committed to a new kind of school, one that would offer all children the same education in order to permit active and equal participation of all citizens, male and female, in the “new Germany.” Educators estimated that over 90 percent of school-aged children attended school in the postwar years, approximately 15 percent of the entire population. Major change in young people's education could thus potentially bring about major social reform. Yet coeducation did not resolve the so-called “woman's question” of structural inequality, a theory elaborated by the nineteenth-century socialist August Bebel and of grave concern to the “antifascist democratic, educators of the postwar years. The implementation of the coeducational classroom, although an important move towards erasing gross disparities in educational opportunities for girls, still allowed for and even perpetuated gender-specific educational lessons and experiences.
Mutual Subversion: A Short History of the Liberal and the Professional in American Higher Education
Authors: Labaree David F.
Published: January 2007

I want to tell a story about American higher education. Like many historical accounts, this story has a contrapuntal quality. As we know, historians frequently find themselves trying to weave discordant themes into complex patterns in the hope of making harmony. The reason for this is that simple themes are hard to find in the account of any complex social institution, especially one like education, which is composed of a motley accumulation of historical residues and social functions. We often come across one point about education that makes sense and then find a counterpoint that also makes sense. If we cannot eliminate one in favor of the other, then we try to put them together in a way that does not violate the rules of harmony and historical logic. In the effort to do so we, therefore, find ourselves in the business of writing fugues.
The Connection of Samuel Chapman Armstrong as Both Borrower and Architect of Education in Hawai'i
Authors: Beyer C. Kalani
Published: January 2007

Samuel Chapman Armstrong is well known for establishing Hampton Institute, the institution most involved with training black teachers in the South after the Civil War. It is less known that he was born in Hawai'i to the missionary couple Reverend Richard and Clarissa Chapman Armstrong. His parents were members of the Fifth Company of missionaries that arrived in Hawai'i in 1831. Reverend Armstrong withdrew from the mission in 1848 to become the Minister of Public Instruction. Until Reverend Armstrong's death in 1860, he was the major force behind education for Hawaiians in both missionary and public schools
Damage Detection in Simply Supported Concrete Bridge Structure Under Moving Vehicular Loads
Authors: Zhu X. Q. , Law S. S.
Published: January 2007

A method for damage detection of a simply supported concrete bridge structure in time domain is presented using the interaction forces from the moving vehicles as excitation. The vehicular loads are modeled as a group of vehicle-bridge interaction forces moving at a prescribed velocity, and the bridge is modeled as an Euler-Bernoulli beam simply supported at both ends. A damage function is used to simulate the crack damage in the reinforced concrete beam. The vehicle-bridge interaction forces and the structural damage in the bridge deck are identified from the measured responses in sequence of iteration without prior knowledge of the moving loads. The effects of parameters of the vehicle-bridge system and measurement noise on the damage detection result are studied. Simulation results show that the method is effective and noise insensitive to damage detection in the concrete bridge structure under moving vehicular loads.
Re-sequencing of Design Processes With Activity Stochastic Time and Cost: An Optimization-Simulation Approach
Authors: Abdelsalam Hisham M. E. , Bao Han P.
Published: January 2007

Background. By the mid-1990s, the importance of the early introduction of new products to both market share and profitability became fully understood. Thus, reducing product time-to-market became an essential requirement for continuous competition. Coupled with the fact that about 70% of the life cycle cost of a product is committed at early design phases, the motivation for developing and implementing more effective methodologies for managing the design process of new product development projects became very strong. Method of Approach. One tool that helps in understanding and analyzing such a project is the design structure matrix (DSM). This paper presents a framework that obtains an optimum sequence of project activities—presented by the DSM—that minimizes total time and cost given stochastic activity estimated time and cost. The framework interfaces a meta-heuristic optimization algorithm called simulated annealing with a commercial risk analysis software. Results. The proposed framework was applied to a design project and the results have shown a robust solution minimum was reached. Conclusions. Since much of the time and cost involved in the design process is attributable to its expensive iterative nature. The framework presented in this paper improves a design project via obtaining an optimum sequence of its activities that minimizes total time and cost.
Vibration and Stability of a Shallow Arch Under a Moving Mass-Dashpot-Spring System
Authors: Chen Jen-San , Yang Min-Ray
Published: January 2007

In this paper we study the dynamic behavior of a shallow arch under a moving load system containing two masses, a dashpot, and a suspension spring. It is assumed that the masses in the load system are under the action of gravity. This paper is an extension of a previous publication in which the arch is loaded by a moving point force. The emphasis of the paper is placed on finding out how the inertia effect of the load system affects the dynamic response of the arch. It is found that the point-force model is a good approximation only when the arch is slender and the moving speed of the load system is low. The boundary of a dangerous speed zone is defined based on the comparison of the total energy gained by the arch and an energy barrier. It is observed that the suspension model predicts a considerably different dangerous speed zone from the one predicted by the point-force model, especially in the high-speed range.