bluuebunny/crossref_metadata_2025_split huggingface dataset:
Field population biology of citrus whitefly, Dialeurodes citri (Ashmead) (Heteroptera: Aleyrodidae), on oranges in California
Authors: Bellows T. S. , Meisenbacher C. 
Published: January 2007

AbstractPopulations of Dialeurodes citri (Ashmead) on oranges were studied in two orange orchards in southern California, USA, to quantify developmental times and mortalities affecting this species. Four populations were followed in detail for three generations over 2 years, by monitoring the development and survival of 200 individuals in each population. Overall, preimaginal mortality among the generation studied varied from 56 to 94%. No evidence of disease or parasitism was present in the populations, and mortality was likely due to generalist predators. Weather records for the period were typical for the region, and periods of rainfall or elevated temperatures did not show any correlation with periods of mortality in the populations. Overall, the populations have high survival rates for whitefly populations, and this high survival is likely a major contributing factor to their pest status in California orchards. Addition of natural enemies to reduce the survival rates of these populations is proposed as the next course of action in suppressing populations below damaging levels.
Morphology of the forced oscillatory flow past a finite-span wing at low Reynolds number
Authors: PARKER K. , VON ELLENRIEDER K. D. , SORIA J. 
Published: January 2007

A study of the morphology of the vortical skeleton behind a flapping NACA0030 wing with a finite aspect ratio of 3, is undertaken. The motivation for this work originates with the proposal that thrust can be efficiently produced by flapping aerofoils. The test condition corresponds to a Strouhal number of 0.35, Reynolds number, based on aerofoil chord, of 600 and an amplitude of flapping, equal to the chord length of the wing. This test condition corresponds to the optimal thrust-producing case in infinite-span flapping wings. This study investigates the effect of wing three-dimensionality on the structure of the wake-flow. This is accomplished here, by quantitatively describing the spatio-temporal variations in the velocity, vorticity and Reynolds stresses for the finite-span-wing case.Preliminary flow visualizations suggest that the presence of wingtip vortices for the three-dimensional-wing case, create a different vortical structure to the two-dimensional-wing case. In the case of a two-dimensional-wing, the flow is characterized by the interaction of leading- and trailing-edge vorticity, resulting in the formation of a clear reverse Kármán vortex street at the selected test condition. In the case of a three-dimensional-wing, the flow exhibits a high degree of complexity and three-dimensionality, particularly in the midspan region. Using phase-averaged particle image velocimetry measurements of the forced oscillatory flow, a quantitative analysis in the plane of symmetry of the flapping aerofoil was undertaken. Using a triple decomposition of the measured velocities, the morphological characteristics of the spanwise vorticity is found to be phase correlated with the aerofoil kinematics. Reynolds stresses in the direction of oscillation are the dominant dissipative mechanism. The mean velocity profiles resemble ajet, indicative of thrust production. Pairs of strong counter-rotating vortices from the leading- and trailing-edge of the aerofoil are shed into the flow at each half-cycle. The large-scale structure of the flow is characterized by constructive merging of spanwise vorticity. The midspan region is populated by cross-sections of interconnected vortex rings.
Mathematics in Context: A Case in Early Nineteenth-Century Korea
Authors: Hoon Jun Yong 
Published: January 2007

ArgumentThis paper aims to show how a nineteenth-century Korean scholar's mathematical study reflects the Korean intellectual environment of his time by focusing on the rule of false double position and the method of root extraction. There were two major trends in Korean mathematics of the early nineteenth century: the first was “Tongsan,” literally “Eastern Mathematics,” which largely depended on Chinese mathematics of the Song and Yuan period adopting counting rod calculation; the second trend was Western mathematics, which was transmitted by the Jesuits and their Chinese collaborators from the late sixteenth century. There was also an intellectual transition in late eighteenth-century Korea when mathematics, which had been of only minor interest for Confucian scholars, became an important part of Confucian pursuits. We can gain an insight into the history of mathematics in Korea by examining and understanding Hong Kil-chu's (1786–1841) mathematical studies and the context of the academic world of his time.
Glutamine gluconeogenesis in the small intestine of 72 h-fasted adult rats is undetectable
Authors: Martin Guy , Ferrier Bernard , Conjard Agnès , Martin Mireille , Nazaret Rémi , Boghossian Michelle , Saadé Fadi , Mancuso Claire , Durozard Daniel , Baverel Gabriel 
Published: January 2007

Recent reports have indicated that 48–72 h of fasting, Type 1 diabetes and high-protein feeding induce gluconeogenesis in the small intestine of adult rats in vivo. Since this would (i) represent a dramatic revision of the prevailing view that only the liver and the kidneys are gluconeogenic and (ii) have major consequences in the metabolism, nutrition and diabetes fields, we have thoroughly re-examined this question in the situation reported to induce the highest rate of gluconeogenesis. For this, metabolically viable small intestinal segments from 72 h-fasted adult rats were incubated with [3-13C]glutamine as substrate. After incubation, substrate utilization and product accumulation were measured by enzymatic and NMR spectroscopic methods. Although the segments utilized [13C]glutamine at high rates and accumulated 13C-labelled products linearly for 30 min in vitro, no substantial glucose synthesis could be detected. This was not due to the re-utilization of [13C]glucose initially synthesized from [13C]glutamine. Arteriovenous metabolite concentration difference measurements across the portal vein-drained viscera of 72 h-fasted Wistar and Sprague–Dawley rats clearly indicated that glutamine, the main if not the only gluconeogenic precursor taken up, could not give rise to detectable glucose production in vivo. Therefore we challenge the view that the small intestine of the adult rat is a gluconeogenic organ.
Role of Safety-Engineered Devices in Preventing Needlestick Injuries in 32 French Hospitals
Authors: Lamontagne F. , Abiteboul D. , Lolom I. , Pellissier G. , Tarantola A. , Descamps J. M. , Bouvet E. 
Published: January 2007

Objectives.To evaluate safety-engineered devices (SEDs) with respect to their effectiveness in preventing needlestick injuries (NSIs) in healthcare settings and their importance among other preventive measures.Design.Multicenter prospective survey with a 1-year follow-up period during which all incident NSIs and their circumstances were reported. Data were prospectively collected during a 12-month period from April 1999 through March 2000. The procedures for which the risk of NSI was high were also reported 1 week per quarter to estimate procedure-specific NSI rates. Device types were documented. Because SEDs were not in use when a similar survey was conducted in 1990, their impact was also evaluated by comparing findings from the recent and previous surveys.Setting.A total of 102 medical units from 32 hospitals in France.Participants.A total of 1,506 nurses in medical or intensive care units.Results.A total of 110 NSIs occurring during at-risk procedures performed by nurses were documented. According to data from the 2000 survey, use of SEDs during phlebotomy procedures was associated with a 74% lower risk (P < .01 ). The mean NSI rate for all relevant nursing procedures was estimated to be 4.72 cases per 100,000 procedures, for a 75% decrease since 1990 (P < .01); however, the decrease in NSI rates varied considerably according to procedure type. Between 1990 and 2000, decreases in the NSI rates for each procedure were strongly correlated with increases in the frequency of SED use (r = 0.88; P < .02).Conclusion.In this French hospital network, the use of SEDs was associated with a significantly lower NSI rate and was probably the most important preventive factor.
Morphological transformation in three mammalian cell systems following treatment with 6-nitrochrysene and 6-nitro-benzo[a]pyrene
Authors: Sala M. , Lasne C. , Lu Y.P. , I. Chouroulinkov 
Published: January 2007

Abstract
Two nitroaromatics, 6-nitrobenzo[a]pyrene (6-N-BaP) and 6-nitrochrysene (6-N-CRY), and the corresponding parent hydrocarbons, benzo[a]pyrene (BaP) and chrysene (CRY), were studied in in vitro transformation assays with Syrian hamster embryo (SHE) cells, BALB/3T3 and C3H10T1/2 mouse cell lines. The three cell systems showed different sensitivities to the transforming effects of the chemicals studied, SHE cells being the most efficient, followed by 3T3 cells and the last being C3H1OT1/2 cells. In the SHE cell system all compounds were active. Considering the concentrations (in μM) and the transformation frequency BaP was the most active, followed by 6-N-BaP, 6-N-CRY and CRY. In the BALB/3T3 standard assay and in the C3H10T1/2 assay only BaP was clearly active. When used as initiators 6-N-BaP and 6-N-CRY were inactive in the C3H cell system. In conclusion 6-N-BaP appears less active in in vitro systems than the parent compound BaP; 6-N-CRY is probably negative since it is questionable in vitro and negative in mouse skin.
Phorbol ester-induced formation of clastogenic factor from human monocytes
Authors: Kozumbo Walter J. , Muehlematter D. , Jörg A. , Emerit I. 
Published: January 2007

Abstract
Phorbol-12-myristate-13-acetate (PMA) acts as a tumor promoter on mouse skin. It induces inflammation and leukocyte-mediated clastogenicity which appears to be related to rapid changes in lipid metabolism. To identify lipids possessing clastogenic and/or tumor-promoting properties, we have characterized the metabolism and release of arachidonic acid (AA) and related lipids during the formation of lipophilic clastogenic factors by PMA-treated human monocytes. In 1 h, [ 3 H]AA-labeled monocytes spontaneously released significant amounts of their total radioactivity (4#) which increased nearly 4-fold (15#) with PMA (30 ng/ml) treatment. Eighty-five per cent of extracellular 3 H-label from both control and PMA-treated monocytes was composed of free AA (plus AA-metabolites), while the remaining radioactivity was incorporated in pbospholipids and mono- and diacylglycerols. Treated and non-treated cells released essentially the same kind of metabolites but PMA induced a 3- to 4-fold increase in total amounts. The major products consisted of prostaglandins F 2α and E 2 , thromboxane B 2 , 12-hydroxy-5,8,10-hepta-decatrienoic acid and 5-, 11- and 15-hydroxyeicosatetraenoic acids. PMA also induced increases in the levels of three unidentified products. Neither leukotrienes nor 4-hydroxy-nonenal, a major alkenal degradation product of AA, were found in medium from PMA-treated monocytes. PMA, in contrast to the first-stage tumor promoter calcium ionophore A23187, failed to stimulate the release of platelet activating factor. The increased formation of phorbol ester-induced AA metabolites was proportional to the increase in free extracellular AA. The source of AA from treated and untreated monocytes consisted of cellular phospholipids with phosphatidylcholine and phosphatidylethanoloamine accounting for 85%.
The clonal nature of carcinogen-induced altered foci of γ-glutamyl transpeptidase expression in rat liver
Authors: Weinberg W.C. , Berkwits L. , Iannaccone P.M. 
Published: January 2007

Abstract
The clonality of tumors has been convincingly established. Because it is generally accepted that tumor formation involves a number of steps, it is important to determine which if any of the precursors of tumors are clonal. A series of chimeric rats produced between congenic strains by morulae aggregation were used to establish the cellular composition of foci of γ-glutamyl transpeptidase (-γ-GTP; E.C. 2.3.2.2) expression in liver following initiation with N -nitrosodiethylamine and promotion with phenobarbital. The chimeras were produced between congenic rat strains (PVG and PVG-RT1 a ) genetically distinguished by alleles of the major histocompatibility complex (MHQ. Monoclonal antibodies directed to distinctive class I MHC alloantigens were used to detect patterns of mosaicism in the animals. The parental genotypes present in most visceral tissues could be easily distinguished by our method. Analysis of 499 enzyme-altered foci revealed that 474 were comprised solely of either PVG-RT1 a or PVG cells. Some apparent mixture of cells from the two lineages was observed in 25 lesions, most of which were very small. The observed pattern of distortion of normal patch distribution clearly indicated the expanding and clonal nature of these lesions.
Suppression by methionine and choline of onco-fetal patterns of liver tRNA methyltransferase activities in carcinogen-treated rats
Authors: Wainfan Elsie , Dizik Mark 
Published: January 2007

Abstract
When male Fischer rats were fed Purina chow supplemented with 2% D,L-methionine and 1% choline chloride, the rapid increase in N2-guanine tRNA methyltransferase II (NMG2) activity otherwise seen in response to cancer-promoting doses (0.02% in the diet) of 2-acetylaminofluorene (AAF) was prevented, and the increase in NMG2 activity otherwise caused by carcinogenic doses of AAF (0.06% in the diet) was decreased by 50%. In addition, the return of NMG2 activity to a normal level after completion of a 3-week regimen of 0.06% AAF was accelerated in animals fed the methionine plus choline supplemented diet. As shown earlier in this laboratory, liver tRNA methylating enzyme activities are shifted rapidly to an onco-fetal pattern in rats receiving methyl-deficient diets. This pattern is characterized by selectively elevated NMG2 activity while the activities of other base-specific tRNA methylating enzymes are relatively unchanged. Our combined results indicate that the exogenous supply of methyl groups is a factor in regulating NMG2 activity and can modulate at least one response of animals to carcinogens.
Recombinant human interleukin 6 (B cell stimulatory factor 2) enhances immunoglobulin secretion by single murine hapten-specific B cells in the absence of cell division
Authors: Alderson Mark R. , Pike Beverley L. 
Published: January 2007

Abstract
We have assessed the role of recombinant human IL-6 (r-hu-IL-6) In promotion of early actlvation, proliferation, and immunoglobulin(lg) secretion amongst single hapten-specific murine splenic B cells in vitro it was found that r-hu-IL-6 acting alone was able to induce early B cell activation in a proportion of B cells, as measured by a significant increase in cell diameter within 24 h. An enhanced effect was seen in the concomitant presence of a ‘T-Independent’ antigen. None of the B cells activated by r-hu-IL-6 appeared to divide, as the frequencies of proliferating clones Induced by either medium alone or antigen alone were virtually identical whether r-hu-IL-6 was present or absent. However, assay of the culture supernatants for the presence of Ig by ELlSA revealed that r-hu-IL-6 effected a significant 2-fold increase in the frequency of B cells secreting Ig. Thus, the prlme effect of r-hu-IL-6 appears to be to recruit more precursor B cells into Ig secretion, rather than to promote proliferation or to enhance the amount of Ig secreted by pre-committed but non-cycling B cells. Delayed addition experiments showed that r-hu-IL-6 enhanced Ig secretion late in the activation pathway. Kinetics studies demonstrated detectable Ig secretion as early as day 2, and when taken with its apparent ability to Induce early activation, these flndings suggest that IL-6 is not exclusively a late-acting Interleukin. Studies with size fractionated hapten-spectflc B cells showed the larger B cells to be preferentially responsive to r-hu-IL-6. The data presented strongly suggest that IL-6 may play a role In B cell maturation as a polyclonal stimulator of low rate Ig secretion. The bioactivity of IL-6 In this slngle cell system thus differed from that of IL-4 and/or IL-5. These findings are discussed with relevance to B cell activation in vivo.
Submandibular Gland Transfer for Severe Xerophthalmia
Authors: Paniello Randal C. 
Published: January 2007

AbstractObjective: To report early clinical experience with a new microvascular reconstructive procedure for patients with severe xerophthalmia.Study Design: Retrospective clinical series.Methods: Patients with severe xerophthalmia were referred for treatment after having exhausted all conventional means of treatment. The ipsilateral submandibular gland was transferred to the temporal fossa, as described by Macleod et al., and revascularized using the superficial temporal artery and appropriate vein(s). The submandibular duct was directed to the superolateral fornix so that the saliva produced moistened the eye. Results and complications were reviewed.Results: Seven microvascular submandibular gland transfer procedures were performed in five patients, ages 6 to 54. The etiology of severe xerophthalmia was Stevens‐Johnson syndrome in four and chemical burn in one. Follow‐up time was 4 to 20 months. Successful transfer with revascularization was achieved in six of seven (86%) cases. Schirmer's test scores improved from 1.3 pretransfer to 8.1 posttransfer (P = .005). Patients experienced symptomatic relief within 1 month, and the microenvironment of the eye surface improved enough to make them candidates for visual restorative eye surgery. There were no major complications.Conclusions: Microvascular submandibular gland transfer is an effective approach for correcting severe xerophthalmia. The procedure should be within the skills of any reconstructive microsurgeon. This procedure offers a unique opportunity for otolaryngologist–head and neck reconstructive surgeons to help restore vision to this unfortunate group of patients.
Supracricoid Laryngectomy Outcomes: The Johns Hopkins Experience
Authors: Farrag Tarik Y. , Koch Wayne M. , Cummings Charles W. , Goldenberg David , Abou‐Jaoude Peter M. , Califano Joseph A. , Flint Paul W. , Webster Kimberly , Tufano Ralph P. 
Published: January 2007

AbstractObjective: To report the oncologic and functional results from our experience in performing supracricoid laryngectomy (SCL) for selected patients with laryngeal cancer.Study Design: Retrospective chart review.Methods: Twenty‐four consecutive patients who underwent SCL for laryngeal cancer in our institution from December 2000 to March 2006 have been reviewed. Reports of the site and extent of tumor, type of reconstruction, preoperative or postoperative radiotherapy, and the final histopathologic examination were reviewed. In addition, the reports of the preoperative examination, inpatient course, and postoperative follow‐up were reviewed.Results: A total of 24 patients were involved in the study; 19 had tumors involving the glottic region, and 5 patients had tumors involving both the glottic and supraglottic regions (transglottic). Ten patients had their SCL for postradiotherapy recurrence/persistence of disease. Eighteen patients underwent reconstruction through cricohyoidoepiglottopexy (CHEP), whereas six patients had cricohyoidopexy (CHP). Eleven patients had an arytenoid cartilage resected; 8 of 11 had CHEP, and 3 of 11 had CHP. All patients had a tracheostomy and percutaneous endoscopic gastrostomy (PEG) tube placement performed at the same time as the SCL. The median hospital stay period was 6 days. Twenty‐three of 24 had successful tracheostomy tube decannulation, with a median time to decannulation of 37 days. The median time to removal of the PEG tube was 70 days. The complications with SCL were postoperative wound infection in two patients (SCL/CHP) and the need for completion total laryngectomy secondary to intractable aspiration in one patient with SCL/CHP. One patient with SCL/CHEP had a ruptured pexy and subsequently underwent a second reconstruction with successful tracheostomy and PEG tube removal. One of 24 patients is still PEG tube dependant, and he had postoperative radiotherapy. Fifteen patients underwent concurrent neck dissection. None of the patients had any local or regional recurrence, with a median follow‐up period of 3 years. All final surgical margins were negative for tumor invasion. Three patients had postoperative radiotherapy, two patients because of nodal metastases in the excised lymph nodes and one because of perineural invasion on final histopathologic examination of the SCL specimen. There were no perioperative deaths.Conclusion: SCL with CHEP or CHP represents an effective technique that can be taught and effectively used to avoid a total laryngectomy while maintaining physiologic speech and swallowing in selected patients with advanced stage primary laryngeal cancer or recurrent/persistent laryngeal cancer after radiotherapy. There is a good functional recovery with acceptable morbidity and an excellent oncologic outcome when strict selection criteria are applied and a formal swallowing rehabilitation program is followed.
Anxiety and Pain Symptoms in Children With Inflammatory Bowel Disease and Functional Gastrointestinal Disorders Undergoing Colonoscopy
Authors: Crandall Wallace V , Halterman Timothy E , Mackner Laura M 
Published: January 2007

ABSTRACTObjective:To compare pain and anxiety scores between children with inflammatory bowel disease (IBD) and those with functional gastrointestinal disorders (FGID) undergoing colonoscopy and to examine the role of anxiety and procedure length in predicting reports of pain.Materials and Methods:Children ages 10 to 18 years undergoing colonoscopy (general anesthesia) for the first time completed pain and anxiety questionnaires immediately before the procedure and a pain questionnaire 48 hours after colonoscopy. The diagnosis was determined by chart review and physician interview.Results:Children with FGID had a longer duration of pain than those with IBD. Children with FGID endorsed a greater total number of the pain descriptors. The FGID group reported higher usual pain severity and greater postprocedural pain. No differences in anxiety were reported. However, higher levels of anxiety were associated with higher pain scores at the time of colonoscopy in children with IBD. It required significantly more time to perform colonoscopy in the IBD group than in the FGID group. Longer procedure duration was positively correlated with pain in children with FGID but not in children with IBD.Conclusions:Children with FGID report more usual pain symptoms and may describe more pain after a colonoscopy when compared with children with IBD. Anxiety appears to play a role in pain severity after colonoscopy in children presenting with IBD, but not in children with FGID.