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961.
Valera MJ Laich F González SS Torija MJ Mateo E Mas A 《International journal of food microbiology》2011,151(1):105-112
The identification of acetic acid bacteria (AAB) from sound grapes from the Canary Islands is reported in the present study. No direct recovery of bacteria was possible in the most commonly used medium, so microvinifications were performed on grapes from Tenerife, La Palma and Lanzarote islands. Up to 396 AAB were isolated from those microvinifications and identified by 16S rRNA gene sequencing and phylogenetic analysis. With this method, Acetobacter pasteurianus, Acetobacter tropicalis, Gluconobacter japonicus and Gluconacetobacter saccharivorans were identified.However, no discrimination between the closely related species Acetobacter malorum and Acetobacter cerevisiae was possible. As previously described, 16S-23S rRNA gene internal transcribed spacer (ITS) region phylogenetic analysis was required to classify isolates as one of those species. These two species were the most frequently occurring, accounting for more than 60% of the isolates. For typing the AAB isolates, both the Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR and (GTG)5-PCR techniques gave similar resolution. A total of 60 profiles were identified. Thirteen of these profiles were found in more than one vineyard, and only one profile was found on two different islands (Tenerife and La Palma). 相似文献
962.
The toxic plant protein ricin has gained notoriety due to wide availability and potential use as a bioterrorism agent, with particular concern for food supply contamination. We have developed a sensitive and selective mass spectrometry-based method to detect ricin in tap water, 2% milk, apple juice, and orange juice. Ricin added to beverage matrices was extracted using antibody-bound magnetic beads and digested with trypsin. Absolute quantification was performed using isotope dilution mass spectrometry with a linear ion trap operating in product-ion-monitoring mode. The method allows for identification of ricin A chain and B chain and for distinction of ricin from ricin agglutinin within a single analytical run. Ricin-bound beads were also tested for deadenylase activity by incubation with a synthetic ssDNA oligomer. Depurination of the substrate by ricin was confirmed by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOFMS). This method was used successfully to extract ricin from each beverage matrix. The activity of recovered ricin was assessed, and quantification was achieved, with a limit of detection of 10 fmol/mL (0.64 ng/mL). 相似文献
963.
Rather than measuring aberrations across the field to quantify the alignment of an optical system, we show how a single, on-axis measurement of the pupil mapping can be used to measure the off-axis performance of the system and determine the state of alignment. In this paper we show how the Abbe sine condition can be used to relate the mapping between the entrance and exit pupils to image aberrations that have linear field dependence. This mapping error then can be used to measure the linear astigmatism caused by the misalignment. Additionally, we present experimental results from the sine condition test on a simple system. 相似文献
964.
Objective: This study was designed to explore the acceptability, feasibility, and initial efficacy of a new shelter-based treatment for victims of intimate partner violence (IPV; i.e., Helping to Overcome PTSD through Empowerment [HOPE]). Method: A Phase I randomized clinical trial comparing HOPE (n = 35) with standard shelter services (SSS) (n = 35) was conducted. Primary outcome measures included the Clinician-Administered PTSD Scale (CAPS; D. D. Blake et al., 1995) and the Conflict Tactic Scales-Revised (M. A. Straus, S. L. Hamby, S. Boney-McCoy, & D. B. Sugarman, 1996). Participants were followed at 1-week, 3- and 6-months postshelter. Results: Participants reported HOPE to be credible and indicated a high degree of satisfaction with treatment. Only 2 women withdrew from treatment. Both intent to treat (ITT) and minimal attendance (MA) analyses found that HOPE treatment relative to SSS was significantly associated with a lower likelihood of reabuse over the 6-month follow-up period (OR = 5.1, RR = 1.75; OR = 12.6, RR = 3.12, respectively). Results of hierarchical linear model analyses found a significant treatment effect for emotional numbing symptom severity in the ITT sample, t(67) = ?2.046, p 相似文献
965.
Kimberly Belli Sara Wadia-Fascetti Carey Rappaport 《Canadian Metallurgical Quarterly》2011,25(1):10-20
Integrated sensor and media modeling environment has been developed to simulate subsurface sensing systems and environmental parameters relevant to the subsurface sensing modalities. The modeling environment is designed to represent complexity in subsurface features, sensor models, and the integration of the sensors with the subsurface environment. The ability to model complex subsurface environments and any potential random distribution of subsurface properties allows for realistic modeling of heterogeneous subsurface environments such as bridged deck/pavement systems. Many applications can benefit from the modeling, simulation, and interpretation capabilities in the new modeling environment that supports improved understanding of system behavior through simulations to evaluate the ability of a particular modality to detect defects. While numerous modeling packages exist to simulate different wave-based modalities, the integrated sensor and media modeling environment is developed to, in a straightforward manner, physically represent the complex subsurface civil infrastructure environment. Physical modeling capabilities enable the object-oriented programming environment facility portability to other application domains as a generic volume serves as the boundaries for internal elements modeled to represent realistic changes in material properties and buried objects. Model development is demonstrated on a realistic bridge deck example. 相似文献
966.
Callahan Kristin L.; Scaramella Laura V.; Laird Robert D.; Sohr-Preston Sara L. 《Canadian Metallurgical Quarterly》2011,25(1):68
Neighborhood dangerousness and belongingness were expected to moderate associations between harsh parenting and toddler-age children's problem behaviors. Fifty-five predominantly African American mothers participated with their 2-year old children. Neighborhood danger, neighborhood belongingness, and children's problem behaviors were measured with mothers' reports. Harsh parenting was measured with observer ratings. Analyses considered variance common to externalizing and internalizing problems, using a total problems score, and unique variance, by controlling for internalizing behavior when predicting externalizing behavior, and vice versa. Regarding the common variance, only the main effects of neighborhood danger and harsh parenting were significantly associated with total problem behavior. In contrast, after controlling for externalizing problems, the positive association between harsh parenting and unique variance in internalizing problems became stronger as neighborhood danger increased. No statistically significant associations emerged for the models predicting the unique variance in externalizing problems or models considering neighborhood belongingness. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
967.
Mei Li Sara Johnson Hongtao Guo Erik Dujardin Stephen Mann 《Advanced functional materials》2011,21(5):851-859
The mechanism of gold nanoparticle chain assembly associated with the induction of electric dipole–dipole interactions arising from the partial ligand exchange of surface‐adsorbed citrate ions by mercaptoethanol is investigated. UV‐vis spectrophotometry and electron microscopy are used, respectively, to determine the kinetics and time‐dependent structural changes associated with formation of the 1D nanoparticle superstructures between 5 and 50 °C. The results indicate that assembly of the plasmonic nanoparticle networks is extremely sensitive to changes in temperature. Formation of the nanoparticle chains is optimized at 25–30 °C and follows first order kinetics with increasing reaction rates attained for higher initial nanoparticle concentrations. Below 25 °C, plasmonic nanoparticle networks are produced but at a considerably reduced rate. In contrast, above 30 °C, short‐chain networks form rapidly but the process is superseded by a secondary mechanism that limits chain growth and produces small fragments and isolated Au nanoparticles. The changes in assembly behavior are attributed to the temperature‐dependent ordering and disordering of mercaptoethanol molecules associated with the gold nanoparticle surface. The results provide a general mechanistic model for the self‐assembly of metallic nanoparticles based on ligand‐induced electric dipolar interactions, which are globally under thermodynamic control but sensitive to kinetic aspects. It is also shown that the dipolar mechanism can be further exploited to introduce larger nanoparticles as topological dopants that reside specifically at branching points or termini in the self‐assembled 1D nanoparticle networks. 相似文献
968.
Movassaghian S Barzegar-Jalali M Alaeddini M Hamedyazdan S Afzalifar R Zakeri-Milani P Mohammadi G Adibkia K 《Drug development and industrial pharmacy》2011,37(7):849-854
Administration of lidocaine and nonsteroidal anti-inflammatory drugs (NSAIDs) as a routine procedure for relief of dental pains by and large is restricted due to some side effects. Amitriptyline (AM) has long been known to exert analgesic activity as a result of blocking the Na? channels. The objective of the present investigation was to prepare suitable buccoadhesive tablets using cellulose derivatives in order to obtain new formulations containing AM to provide local analgesic action. The tablets were evaluated in terms of physical characteristics, mucoadhesion performance, drug release, and in vivo assessment of analgesic efficiency. Tablets containing higher amounts of high-viscosity hydroxypropylmethyl cellulose (HPMC-K4M) significantly demonstrated enhanced adhesive performances. On the other hand, presence of sodium carboxymethyl cellulose (NaCMC) in formulations including HPMC of lower-viscosity grade (HPMC-E5LV) provided further adhesiveness by increase in viscosity. Rate of drug release from HPMC-E5LV tablets was significantly higher than the HPMC-K4M tablets. Kinetically, patterns of AM release from the tablets fitted best to Higuchi model. Moreover, in a randomized double-blind trial, analgesic efficiency of the prepared bioadhesive tablets was revealed to be satisfactory. It is suggested that applying the topical AM mucoadhesive tablet containing the low amount of drug is a safe and promising alternative to relief the pain in the buccal region. 相似文献
969.
Au/Pd octopods and concave core@shell Au@Pd nanocrystals have been prepared by coupling for the first time a seed-mediated synthetic method with co-reduction. The integration of these two methods is central to the formation of these binary Au/Pd nanocrystals wherein the kinetics of seeded growth are manipulated via the co-reduction technique to control the final morphology of the nanocrystals. Significantly, the synthesis of these structures under similar reaction conditions illustrates that they are structurally related kinetic products. Detailed characterization by STEM-EDX analysis highlights the unique structural features of these nanocrystals and indicates that Pd localizes on the higher-energy features of the nanocrystals. Optical and electrocatalytic characterization also demonstrates their promise as a new class of multifunctional nanostructures. 相似文献
970.
Li Y Tan H Yang XY Goris B Verbeeck J Bals S Colson P Cloots R Van Tendeloo G Su BL 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(4):475-483
Very uniform and well shaped Mn3O4 nano‐octahedra are synthesized using a simple hydrothermal method under the help of polyethylene glycol (PEG200) as a reductant and shape‐directing agent. The nano‐octahedra formation mechanism is monitored. The shape and crystal orientation of the nanoparticles is reconstructed by scanning electron microscopy and electron tomography, which reveals that the nano‐octahedra only selectively expose {101} facets at the external surfaces. The magnetic testing demonstrates that the Mn3O4 nano‐octahedra exhibit anomalous magnetic properties: the Mn3O4 nano‐octahedra around 150 nm show a similar Curie temperature and blocking temperature to Mn3O4 nanoparticles with 10 nm size because of the vertical axis of [001] plane and the exposed {101} facets. With these Mn3O4 nano‐octahedra as a catalyst, the photodecomposition of rhodamine B is evaluated and it is found that the photodecomposition activity of Mn3O4 nano‐octahedra is much superior to that of commercial Mn3O4 powders. The anomalous magnetic properties and high superior photodecomposition activity of well shaped Mn3O4 nano‐octahedra should be related to the special shape of the nanoparticles and the abundantly exposed {101} facets at the external surfaces. Therefore, the shape preference can largely broaden the application of the Mn3O4 nano‐octahedra. 相似文献