985 research outputs found
The discursive flexibility of âflex cropsâ
âFlex cropsâ such as corn, oil palm and soy are understood to have multiple,
interchangeable uses; they have material flexibility. We propose that discursive
flexibility â the ability to strategically switch between discourses to promote an
objective â equally shapes the political economy of flex crops, and thereby patterns
of agrarian and environmental change. Comparing oil palm and Jatropha curcas, we
find that actors who cast oil palm as a multi-scale solution to food and energy
insecurity, climate change and (rural) poverty successfully reinforce its high material
flexibility. Jatrophaâs proponents compensate for low material flexibility by
positioning the crop as a âsustainableâ energy source that achieves both global and
local goals. While this paper focuses on discourses that reinforce the oil palm and
jatropha projects, understanding the power of discursiv
Is There a Need for Preoperative Imaging of the Internal Mammary Recipient Site for Autologous Breast Reconstruction?
Preoperative imaging of recipient-site vasculatur in autologous breast reconstruction may potentiate improved outcomes through the identification of individual variations in vascular architecture. There are a range of both normal and pathologic states which can substantially affect the internal mammary vessels in particular, and the identification of these preoperatively may significantly affect operative approach. There are a range of imaging modalities available, with ultrasound particularly useful, and computed tomography angiography (CTA) evolving as a useful option, albeit with radiation exposure. The benefits of CTA must be balanced against its risks, which include contrast nephrotoxicity and allergic reactions, and radiation exposure. The radiation risk with thoracic imaging is substantially higher than that for donor sites, such as the abdominal wall, with reasons including exposure of the contralateral breast to radiation (with a risk of contralateral breast cancer in this population 2 to 6 times higher than that of primary breast cancer, reaching a 20-year incidence of 15%), as well as proximity to the thyroid gland. Current evidence suggests that although many cases may not warrant such imaging because of risk, the benefits of preoperative CTA in selected patients may outweigh the risks of exposure, prompting an individualized approach
Microtensile Bond Strength Test And Failure Analysis To Assess Bonding Characteristics Of Different Adhesion Approaches To Ground Versus Unground Enamel
This study evaluated the bonding characteristics to ground and unground enamel obtained with different strategies. For this purpose, 24 sound third-molars were bisected mesiodistally to obtain tooth halves. A flat enamel area was delimited in the tooth sections, which were randomly distributed into 8 groups (n=6), according to the enamel condition (ground and unground) and adhesive system (Adper Single Bond 2 - SB2; Adper Prompt L-Pop - PLP; Adper Prompt - AD; Clearfil SE Bond - SE). Each system was applied according manufacturers' instructions and a 6-mm-high resin composite "crown" was incrementally built up on bonded surfaces. Hourglass-shaped specimens with 0.8 mm2 cross-section were produced. Microtensile bond strength (ÎŒTBS) was recorded and the failure patterns were classified. Results were analyzed by two-way ANOVA and Tukey's test (α=0.05). There were no statistically significant differences among the ÎŒTBS values of SB2, PLP and AD (p>0.05). SE values were significantly lower (p0.05). There was prevalence of cohesive failure within enamel, adhesive system and resin composite for SB2. The self-etch systems produced higher incidence of cohesive failures in the adhesive system. Enamel condition did not determine significant differences on bonding characteristics for the same bonding system. In conclusion, the bonding systems evaluated in this study resulted in specific ÎŒTBS and failure patterns due to the particular interaction with enamel.222122128Goes, M.F., Sinhoreti, M.A., Consani, S., Silva, M.A., Morphological effect of the type, concentration and etching time of acid solutions on enamel and dentin surfaces (1998) Braz Dent J, 9, pp. 3-10Swift Jr., E.J., PerdigĂŁo, J., Heymann, H.O., Bonding to enamel and dentin: A brief history and state of the art, 1995 (1995) Quintessence Int, 26, pp. 95-110van Meerbeek, B., Yoshihara, K., Yoshida, Y., de Mine, A.J.M.K.L.V.L., State of the art of self-etch adhesives (2011) Dent Mater, 27, pp. 17-28Mine, A., de Munck, J., Vivan Cardoso, M., van Landuyt, K.L., Poitevin, A., Kuboki, T., Enamel-smear compromises bonding by mild self-etch adhesives (2010) J Dent Res, 89, pp. 1505-1509Kanemura, N., Sano, H., Tagami, J., Tensile bond strength to and SEM evaluation of ground and intact enamel surfaces (1999) J Dent, 27, pp. 523-530Pivetta, M.R., Moura, S.K., Barroso, L.P., Lascala, A.C., Reis, A., Loguercio, A.D., Bond strength and etching pattern of adhesive systems to enamel: Effects of conditioning time and enamel preparation (2008) J Esthet Restor Dent, 20, pp. 322-335Pashley, D.H., Tay, F.R., Aggressiveness of contemporary self-etching adhesives. Part II: Etching effects on unground enamel (2001) Dent Mater, 17, pp. 430-444Di HipĂłlito, V., de Goes, M.F., Carrilho, M.R., Chan, D.C., Daronch, M., Sinhoreti, M.A., SEM evaluation of contemporary self-etching primers applied to ground and unground enamel (2005) J Adhes Dent, 7, pp. 203-211Mjor, I.A., Moorhead, J.E., Dahl, J.E., Reasons for replacement of restorations in permanent teeth in general dental practice (2000) Int Dent J, 50, pp. 361-366Burrow, M.F., Tyas, M.J., 1-year clinical evaluation of one-step in non-carious cervical lesions (1999) Am J Dent, 12, pp. 283-285Opdam, N.J., Roeters, F.J., Feilzer, A.J., Verdonschot, E.H., Marginal integrity and postoperative sensitivity in Class 2 resin composite restorations in vivo (1998) J Dent, 26, pp. 555-562PerdigĂŁo, J., Lambrechtes, P., van Meerbee, K.B., Vanherle, G., Lopes, A.L., Filed emission SEM comparison of four postfixation drying techniques for human dentin (1995) J Biomed Mater Res, 290, pp. 1111-1120Sano, H., Shono, T., Sonoda, H., Takatsu, T., Ciucchi, B., Carvalho, R., Relationship between surface area for adhesion and tensile bond strength. Evaluation of a micro-tensile bond test (1994) Dent Mater, 10, pp. 236-240Shinchi, M.J., Soma, K., Nakabayashi, N., The effect of phosphoric acid concentration on resin tag length and bond strength of a photo-cured resin to acid-etched enamel (2000) Dent Mater, 16, pp. 324-329Yoshida, Y., Nagakane, K., Fukuda, R., Nakayama, Y., Okazaki, M., Shintani, H., Comparative study on adhesive performance of functional monomers (2004) J Dent Res, 83, pp. 454-458Takahashi, A., Sato, Y., Uno, S., Pereira, P.N.R., Sano, H., Effects of mechanical properties of adhesive resins on bond strength to dentin (2002) Dent Mater, 18, pp. 263-268Salz, U., Zimmermann, J., Zeuner, F., Moszner, N., Hydrolytic stability of self-etching adhesive systems (2005) J Adhes Dent, 7, pp. 107-116Cehreli, Z.C., Altay, N., Effects of a nonrinse conditioner and 17% ethylenediaminetetraacetic acid on the etch pattern of intact human permanent enamel (2000) Angle Orthod, 70, pp. 22-27Camps, J., Pashley, D.H., Buffering action of human dentin in vitro (2000) J Adhes Dent, 2, pp. 39-50Ripa, L.W., Gwinnett, A.J., Buonocore, M.G., The "prismless" outer layer of deciduous and permanent enamel (1966) Arch Oral Biol, 11, pp. 41-4
The PKC, HOG and Ca2+ signalling pathways co-ordinately regulate chitin synthesis in Candida albicans
Open Access via PMC2649417Peer reviewedPublisher PD
Imposed registries within the European postmarketing surveillance system: Extended analysis and lessons learned for regulators
Purpose: Building on previous research, we examined whether delayed study start and low patient accrual rates found in 31 postauthorization registry-based studies requested by European Medicines Agency (EMA) are maintained after 2 additional years of follow-up. Method: The registries identified in the previous EMA study and the same methodology were used. The follow-up was extended from June 2015 to November 2017. The information available for the following variables was updated: marketing authorization status, study and registry status, study end date, planned duration, number of patients planned to be enrolled, and actual patients enrolled. Data were collected from several nonpublic in-house sources such as the study protocols, interim and final study reports, risk management plans, and periodic safety update reports. Results: As of November 2017, 10 (32.2%) studies were finalized (vs. 9.7% as of June 2015), 14 (45.2%) were still ongoing (vs. 64.5%). Four of the ongoing studies had patients' accrual lower than 50%. Six of the finalized studies had a delayed completion, with a median delay of 3 years. As of November 2017, the median patients' accrual percentages were 24% for ongoing studies (vs. 8.5%) and 101% for finalized studies (vs. 24%). Conclusion: Overall, the rate of recruitment and timely finalization were improved after 2 years of additional follow-up but show that further work is needed to facilitate use of registry data for regulatory purposes, a work that has started via the EMA registry initiative
Mechanisms of linezolid resistance among enterococci of clinical origin in Spainâdetection of optrA-and cfr(D)-carrying E. faecalis
The mechanisms of linezolid resistance among 13 E. faecalis and 6 E. faecium isolates, recovered from six Spanish hospitals during 2017â2018, were investigated. The presence of acquired linezolid resistance genes and mutations in 23S rDNA and in genes encoding for ribosomal proteins was analyzed by PCR and amplicon sequencing. Moreover, the susceptibility to 18 antimicrobial agents was investigated, and the respective molecular background was elucidated by PCR-amplicon sequencing and whole genome sequencing. The transferability of the linezolid resistance genes was evaluated by filter-mating experiments. The optrA gene was detected in all 13 E. faecalis isolates; and one optrA-positive isolate also carried the recently described cfr(D) gene. Moreover, one E. faecalis isolate displayed the nucleotide mutation G2576T in the 23S rDNA. This mutation was also present in all six E. faecium isolates. All linezolid-resistant enterococci showed a multiresistance phenotype and harbored several antimicrobial resistance genes, as well as many virulence determinants. The fexA gene was located upstream of the optrA gene in 12 of the E. faecalis isolates. Moreover, an erm(A)-like gene was located downstream of optrA in two isolates recovered from the same hospital. The optrA gene was transferable in all but one E. faecalis isolates, in all cases along with the fexA gene. The cfr(D) gene was not transferable. The presence of optrA and mutations in the 23S rDNA are the main mechanisms of linezolid resistance among E. faecalis and E. faecium, respectively. We report the first description of the cfr(D) gene in E. faecalis. The presence of the optrA and cfr(D) genes in Spanish hospitals is a public health concern
Analysis of a spatial Lotka-Volterra model with a finite range predator-prey interaction
We perform an analysis of a recent spatial version of the classical
Lotka-Volterra model, where a finite scale controls individuals' interaction.
We study the behavior of the predator-prey dynamics in physical spaces higher
than one, showing how spatial patterns can emerge for some values of the
interaction range and of the diffusion parameter.Comment: 7 pages, 7 figure
Life path analysis: scaling indicates priming effects of social and habitat factors on dispersal distances
1. Movements of many animals along a life-path can be separated into repetitive ones within home ranges and transitions between home ranges. We sought relationships of social and environmental factors with initiation and distance of transition movements in 114 buzzards Buteo buteo that were marked as nestlings with long-life radio tags.
2. Ex-natal dispersal movements of 51 buzzards in autumn were longer than for 30 later in their first year and than 35 extra-natal movements between home ranges after leaving nest areas. In the second and third springs, distances moved from winter focal points by birds that paired were the same or less than for unpaired birds. No post-nuptial movement exceeded 2 km.
3. Initiation of early ex-natal dispersal was enhanced by presence of many sibs, but also by lack of worm-rich loam soils. Distances travelled were greatest for birds from small broods and with relatively little short grass-feeding habitat near the nest. Later movements were generally enhanced by the absence of loam soils and short grassland, especially with abundance of other buzzards and probable poor feeding habitats (heathland, long grass).
4. Buzzards tended to persist in their first autumn where arable land was abundant, but subsequently showed a strong tendency to move from this habitat.
5. Factors that acted most strongly in œ-km buffers round nests, or round subsequent focal points, usually promoted movement compared with factors acting at a larger scale. Strong relationships between movement distances and environmental characteristics in œ-km buffers, especially during early ex-natal dispersal, suggested that buzzards became primed by these factors to travel far.
6. Movements were also farthest for buzzards that had already moved far from their natal nests, perhaps reflecting genetic predisposition, long-term priming or poor habitat beyond the study area
Phase I clinical trial in healthy adults of a nasal vaccine candidate containing recombinant hepatitis B surface and core antigens
SummaryBackgroundThe nasal vaccine candidate (NASVAC), comprising hepatitis B virus (HBV) surface (HBsAg) and core antigens (HBcAg), has been shown to be highly immunogenic in animal models.MethodsA phase I double-blinded, placebo-controlled randomized clinical trial was carried out in 19 healthy male adults with no serologic markers of immunity/infection to HBV. This study was aimed at exploring the safety and immunogenic profile of nasal co-administration of both HBV recombinant antigens. The trial was performed according to Good Clinical Practice guidelines. Participants ranged in age from 18 to 45 years and were randomly allocated to receive a mixture of 50ÎŒg HBsAg and 50ÎŒg HBcAg or 0.9% physiologic saline solution, as a placebo, via nasal spray in a five-dose schedule at 0, 7, 15, 30, and 60 days. A total volume of 0.5ml was administered in two dosages of 125ÎŒl per nostril. Adverse events were actively recorded 1h, 6h, 12h, 24h, 48h, 72h, 7 days and 30 days after each dose. Anti-HBs and anti-HBc titers were evaluated using corresponding ELISA kits at days 30 and 90.ResultsThe vaccine candidate was safe and well tolerated. Adverse reactions included sneezing (34.1%), rhinorrhea (12.2%), nasal stuffiness (9.8%), palate itching (9.8%), headache (9.8%), and general malaise (7.3%). These reactions were all self-limiting and mild in intensity. No severe or unexpected events were recorded during the trial. The vaccine elicited anti-HBc seroconversion in 100% of subjects as early as day 30 of the immunization schedule, while a seroprotective anti-HBs titer (â„10IU/l) was at a maximum at day 90 (75%). All subjects in the placebo group remained seronegative during the trial.ConclusionThe HBsAgâHBcAg vaccine candidate was safe, well tolerated and immunogenic in this phase I study in healthy adults. To our knowledge, this is the first demonstration of safety and immunogenicity for a nasal vaccine candidate comprising HBV antigens
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