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Biogeography, phylogeography and ecology of the diverse assemblage that inhabits the south-east Pacific along the Humboldt Current system (HCS) has received increasing attention. Regions separated by biogeographic break evidence changes in the functional structure of consumer assemblages, likely related to a replacement from tropical to temperate species. The deep temporal signature of coastal oceanography on coastal biogeography and phylogeography is underpinned by the spatial structure of bottom-up effects of ecological processes, which also influence the strong top-down regulation of consumers on the structure of rocky shore communities. Uncertainties still remain about how coastal oceanographic processes regulate species range expansion/contraction and how biotic interactions and environmental filtering define dynamic biogeographic patterns along marine environments. Explicit predictions should be made regarding the persistence and dynamics of species ranges, and changing ecological interactions among species in the face of intensified human harvesting (e.g., kelps) and global change. Clear cooling trends are observed across the HCS, human harvesting is intensifying and presence of coastal artificial infrastructure could trigger species range shift. Aquaculture expansion and the introduction of exotic non-native species have the potential to alter community structure and functioning. Hence, ecosystem services should be managed, and necessary interventions carefully planned to ensure sustainability of use of natural marine resources and coastal ecosystem integrity.
The solvent-casting method was used to synthesize a silver–zeolite–chitosan (AgZ-Ch) composite from Philippine natural zeolites. X-ray diffraction, ultraviolet–visible (UV-Vis) spectroscopy, optical emission spectroscopy (OES), thermogravimetric analysis (TGA) and differential thermogravimetry (DTG) were used to investigate the different properties of the composite before and after plasma treatment. The major phase of the zeolite is Na-clinoptilolite with trace amounts of mordenite, feldspar and quartz. UV-Vis and OES analyses confirmed the presence of Ag and zeolite on the chitosan matrix. The decrease in the transmittance signal at 290 nm and the emission spectra of the discharge showed the presence of Ag I, Al I and Si I signals at 705–852 nm. The TGA and DTG curves revealed the thermal stability of the natural zeolites after ion exchange and after incorporation in the chitosan matrix, where the onset of degradation was observed to occur above ~37°C, the human body temperature. Bacterial count showed minimal growth of colonies on all samples, both pristine and plasma-treated, suggesting that the surface of the composites does not influence bacterial habitation. The fabricated composites meet the minimum requirements for biomedical application such as thermal stability with respect to the average human body temperature and absence of bacteria.
Rosin resin is constituted by rosin acids, in particular, abietic acid, which is an inexpensive substance. This paper concerns the study of the molecular interactions between a bifunctional monomer of abietic acid with isocyanate to form polyurethane. Polyurethane is a varnish that can be applied to any timber surface protecting it from chemical and environmental factors. Furthermore, the polar groups (OH´s) of the diol have a direction along the molecular axis thus, increasing their intermolecular interactions with the isocyanate groups. The varnish named as (PAR), was synthesized in the laboratory and applied to a timber surface whereby its functionality was evaluated. Morphological and spectroscopic studies were carried out on the diol obtained and the polyurethane. Likewise, we behaved several of physical and chemical analyses of vanish. The comparative SEM showed a homogeneous phase on the PAR surface and FTIR between the diphenylmethane, 4-4, diisocyanate (MDI) and the varnish from hydroxylated rosin resin (HAA) showed that the reaction was carried out in its entirety, exhausting the limiting reagent (MDI). The obtained varnish which was labelled as PAR has very suitable characteristics for indoor use. It has a transparent and bright appearance, a solids percentage of 44-45%, a drying time for application between layers and layers of 15-20 minutes.
OBJECTIVES/SPECIFIC AIMS: To build a multisite de-identified database of female adolescents, aged 12–21 years (January 2011–December 2012), and their subsequent offspring through 24 months of age from electronic health records (EHRs) provided by participating Community Health. METHODS/STUDY POPULATION: We created a community-academic partnership that included New York City Community Health Centers (n=4) and Hospitals (n=4), The Rockefeller University, The Sackler Institute for Nutrition Science and Clinical Directors Network (CDN). We used the Community-Engaged Research Navigation model to establish a multisite de-identified database extracted from EHRs of female adolescents aged 12–21 years (January 2011–December 2012) and their offspring through 24 months of age. These patients received their primary care between 2011 and 2015. Clinical data were used to explore possible associations among specific measures. We focused on the preconception, prenatal, postnatal periods, including pediatric visits up to 24 months of age. RESULTS/ANTICIPATED RESULTS: The analysis included all female adolescents (n=122,556) and a subset of pregnant adolescents with offspring data available (n=2917). Patients were mostly from the Bronx; 43% of all adolescent females were overweight (22%) or obese (21%) and showed higher systolic and diastolic blood pressure, blood glucose levels, hemoglobin A1c, total cholesterol, and triglycerides levels compared with normal-weight adolescent females (p<0.05). This analysis was also performed looking at the nonpregnant females and the pregnant females separately. Overall, the pregnant females were older (mean age=18.3) compared with the nonpregnant females (mean age=16.5), there was a higher percentage of Hispanics among the pregnant females (58%) compared with the nonpregnant females (43.9%). There was a statistically significant association between the BMI status of mothers and infants’ birth weight, with underweight/normal-weight mothers having more low birth weight (LBW) babies and overweight/obese mothers having more large babies. The odds of having a LBW baby was 0.61 (95% CI: 0.41, 0.89) lower in obese compared with normal-weight adolescent mothers. The risk of having a preterm birth before 37 weeks was found to be neutral in obese compared with normal-weight adolescent mothers (OR=0.81, 95% CI: 0.53, 1.25). Preliminary associations are similar to those reported in the published literature. DISCUSSION/SIGNIFICANCE OF IMPACT: This EHR database uses available measures from routine clinical care as a “rapid assay” to explore potential associations, and may be more useful to detect the presence and direction of associations than the magnitude of effects. This partnership has engaged community clinicians, laboratory, and clinical investigators, and funders in study design and analysis, as demonstrated by the collaborative development and testing of hypotheses relevant to service delivery. Furthermore, this research and learning collaborative is examining strategies to enhance clinical workflow and data quality as well as underlying biological mechanisms. The feasibility of scaling-up these methods facilitates studying similar populations in different Health Systems, advancing point-of-care studies of natural history and comparative effectiveness research to identify service gaps, evaluate effective interventions, and enhance clinical and data quality improvement.
OBJECTIVES/SPECIFIC AIMS: To build a multisite deidentified database of female adolescents, aged 12–21 years (January 2011–December 2012), and their subsequent offspring through 24 months of age from electronic health records (EHRs) provided by participating Community Health. METHODS/STUDY POPULATION: We created a community-academic partnership that included New York City Community Health Centers (n=4) and Hospitals (n=4), The Rockefeller University, The Sackler Institute for Nutrition Science and Clinical Directors Network (CDN). We used the Community-Engaged Research Navigation model to establish a multisite deidentified database extracted from EHRs of female adolescents aged 12–21 years (January 2011–December 2012) and their offspring through 24 months of age. These patients received their primary care between 2011 and 2015. Clinical data were used to explore possible associations among specific measures. We focused on the preconception, prenatal, postnatal periods, including pediatric visits up to 24 months of age. RESULTS/ANTICIPATED RESULTS: The preliminary analysis included all female adolescents (n=49,292) and a subset of pregnant adolescents with offspring data available (n=2917). Patients were mostly from the Bronx; 43% of all adolescent females were overweight (22%) or obese (21%) and showed higher systolic and diastolic blood pressure, blood glucose levels, hemoglobin A1c, total cholesterol, and triglycerides levels compared with normal-weight adolescent females (p<0.05). There was a statistically significant association between the BMI status of mothers and infants’ birth weight, with underweight/normal-weight mothers having more low birth weight (LBW) babies and overweight/obese mothers having more large babies. The odds of having a LBW baby was 0.61 (95% CI: 0.41, 0.89) lower in obese compared with normal-weight adolescent mothers. The risk of having a preterm birth before 37 weeks was found to be neutral in obese compared to normal-weight adolescent mothers (OR=0.81, 95% CI: 0.53, 1.25). Preliminary associations are similar to those reported in the published literature. DISCUSSION/SIGNIFICANCE OF IMPACT: This EHR database uses available measures from routine clinical care as a “rapid assay” to explore potential associations, and may be more useful to detect the presence and direction of associations than the magnitude of effects. This partnership has engaged community clinicians, laboratory and clinical investigators, and funders in study design and analysis, as demonstrated by the collaborative development and testing of hypotheses relevant to service delivery.
Chitosan is biocompatible polymer has a great commercial interest because it can be processed in a sort of devices varying in shape and size, such as membranes, gels and nanoparticles. Mostly, the cell’s attachment and proliferation are very positive on nanostructurated materials with a three-dimensional formation. An irreversible network can be produced by covalently binding the polymer to the cross-linker molecules. Chitosan nanoparticles were prepared using glutaraldehyde as cross-linker. This crosss-liker mostly reacts with chitosan amino groups. In order to control and understand the physical characteristics of chitosan nanoparticle, in this work is showed the molecular behavior of chitosan/glutaraldehyde from the viewpoint of molecular interactions base in a series of molecular dynamics (MD) computer simulation. The results indicated the conformations of both molecules, which had a significant influence on the molecular association. The chitosan chains were uniformly distributed presenting a high flexibility and preference for the relaxed two-fold helix. This was due to the various associations such as intramolecular chitosan interactions –O-H···O-C-. While the chitosan-glutaraldehyde associations were due to the positive net charge density of hydrogens in the chitosan plus - H2N···C=O associations. In solid state chitosan nano and microparticles were analyzed by scanning electron microscopy (SEM). According to the micrographs results, the nanoparticles presented a monomorphism with piles of particles arranged in linear order which was consistent with the conformations determined by simulation.
Aluminum titanium oxynitride (TiAlNO) coatings were deposited on 316 steel substrates by the sputtering technique, varying the nitrogen flow from 2.5, 5, 7.5 to 10 sccm, and maintaining constant at 12 sccm the flow argon gas. We used targets of titanium and alumina with 99.995% purity. The hardness and tribological analyses were determined by Vickers microhardness and tribology (tribometer pin-disc), respectively. The results show that the coating with a nitrogen flow of 10 sccm had the lowest volumetric wear (2.047738693 mm3) and the maximum value of hardness (11.2 GPa). Analysis of X-ray diffraction evidenced the presence of three crystalline phases: Ti2N, Al2O3 and TiO2. It can be observed that by increasing the nitrogen flow, the portion of semi-Ti2N phase increases, Al2O3 decreases and TiO2 remains almost constant, and also producing a change in crystallographic orientation with reference to the Ti2N phase. Crystal grain sizes were estimated by X-ray diffraction Fourier line profile analysis using Warren–Averbach method. This analysis showed a grain size between 5 and 15 nm. Raman spectroscopy results show the presence of the TiO2 phase which corroborated the X-ray diffraction results.
Chitin nanowhiskers were obtained with the purpose to be used as astaxanthin protectors against the photo and thermal degradation. These nanostructures were generated by a freezing/thawing procedure using two stirring methods: mechanical and sonication, which were named as FTM and FTS respectively. Morphological and spectroscopic studies were carried out on chitin nanowhiskers by scanning electronic microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Through a SEM analysis, chitin fibers were found uniformly spaced and oriented with the width ranged from of 20-40 nm. Furthermore, the nanowhiskers obtained by FTM showed long and flattened structures and bundles of homogeneous sizes, which have the capacity of being sites of stress concentration. In contrast, by FTS, the nanowhiskers showed coarse fibers exhibiting numerous peaks. By comparing the two methods is appreciated that FTS method provides more surface area, giving more sites for functionalization. Fourier transform infrared spectroscopy (FTIR) allowed the determination of free movement of functional groups on the surface of samples obtained by FTM and FTS methods. Significant differences of signals in the spectra indicate that there were more unassociated amides in the nanowhiskers obtained by FTS than by FTM.
Poly(acrylamide-co-2-hydroxyethyl methacrylate), hydrogel microparticles were prepared by free radical copolymerization of acrylamide (AAm) and 2-hydroxyethyl methacrylate (2-HEMA) using an inverse emulsion polymerization technique, employing ethylene glycol dimethylacrylate (EGDMA) as crosslinker in the presence of w/o emulsifiers span-80 and span-85 (sorbitol mono-oleate) above the lower critical solution temperature. Water absorption capacity and characteristics of the hydrogel microparticles were analyzed by Optical Microscopy (OM), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetric Analysis (TGA). Thus, microparticles were submitted to a gravimetric study on their ability to absorb and to retain distilled water at 25°C. One gram of microparticles absorbed at least 15 g of water. By varying the relative ratio between the continuous phase (hexane and emulsifiers) and the dispersed phase (monomers, initiator and crosslinker), non-agglomerated dispersed particles with nearly spherical shape were obtained having a narrow size distribution in the range from 10 to 20 µm. At a constant value of the emulsifier, and as a result of increasing the stirring rate, a particle size reduction was observed from 13 to 7 µm. The PAAm and PHEMA structures of synthesized hydrogel were confirmed using FTIR analysis. Additionally, through thermal analysis the P(AAm-HEMA) hydrogel showed an increase of water retention and thermal stability due to PAAm addition.
Genealogical and live body weight monthly records from 790 sheep of the Chiapas breed born between 1991 and 2004 were used to characterize the growth curve and estimate (co)variance components for the parameters (A, k and b) of the Gompertz function. The pedigree structure consisted of 790 sheep, including 45 rams and 379 ewes. Estimation of (co)variance components for each growth parameter was achieved using a univariate animal model with the restricted maximum likelihood (REML) method. Estimated values of heritability were: A (adult weight) 0.21 ± 0.06; b (integration constant) 0.25 ± 0.07; k (maturity rate) 0.16 ± 0.06; age at the inflexion estimated as (ln(b)/k) 0.24 ± 0.07; and absolute growth rate as [k*(0.368*A)* ln(A/0.368*A)] 0.22 ± 0.07. The growth of males was 24% (P < 0.05) faster than that of females; adult weight was 25 ± 0.7 kg for males and 23 ± 0.7 kg for females; absolute growth was 59 ± 2 g and 44 ± 2 g per day for males and females respectively. The Chiapas breed of sheep is a small animal with a slow growth curve, probably due to its adaptation to the environmental conditions where it lives. Growth curve can be modified through selection.
Outcome of moderate to severe traumatic brain injury (TBI) includes impaired emotion regulation. Emotion regulation has been associated with amygdala and rostral anterior cingulate (rACC). However, functional connectivity between the two structures after injury has not been reported. A preliminary examination of functional connectivity of rACC and right amygdala was conducted in adolescents 2 to 3 years after moderate to severe TBI and in typically developing (TD) control adolescents, with the hypothesis that the TBI adolescents would demonstrate altered functional connectivity in the two regions. Functional connectivity was determined by correlating fluctuations in the blood oxygen level dependent (BOLD) signal of the rACC and right amygdala with that of other brain regions. In the TBI adolescents, the rACC was found to be significantly less functionally connected to medial prefrontal cortices and to right temporal regions near the amygdala (height threshold T = 2.5, cluster level p < .05, FDR corrected), while the right amygdala showed a trend in reduced functional connectivity with the rACC (height threshold T = 2.5, cluster level p = .06, FDR corrected). Data suggest disrupted functional connectivity in emotion regulation regions. Limitations include small sample sizes. Studies with larger sample sizes are necessary to characterize the persistent neural damage resulting from moderate to severe TBI during development. (JINS, 2013, 19, 1–14)
Variations in the rate of embryonic malformations of the anchoveta Engraulis ringens in a spawning area off central–southern Chile were assessed. Eggs in stages of development subsequent to blastodisc formation were collected and preserved. Several severe malformations were identified and grouped by: (1) proliferation of disorganized tissue in early and late developmental stages; (2) irregular blastopore closure; and (3) notochordal deformation, of which the second had the highest incidence among the embryos. The average rate of malformation was 5.64%, a value close to that reported for other Clupeiformes and below the rate of 10%, indicating the influence of purely endogenous factors. The expected relationship between temperature variations and malformation rates was not observed, probably because the natural temperature range experienced by the embryos was above that at which severe malformation had previously been observed in the laboratory. The relationship between egg size and malformation rates over the spawning season was not determined; however, a relationship between egg size and malformation rates was detected among the samples from each sampling date, which suggests that malformations may be attributable to endogenous factors rather than to environmental factors acting directly on the eggs in the plankton.
The infrared fluorescence decay and the dispersed emission spectrum are presented for
gaseous benzene following 193 nm laser excitation. They were measured with FIREFLY
(Fluorescence in the InfraRed from Excited FLYing molecules), a new home-made
spectrometer. Redshift and redtail in the CH stretch emission spectra (3.3
μm region) demonstrate that anharmonicity plays a key role when dealing
with high internal energies, as it is the case in the interstellar medium.
The nature of light-emitting porous Si layers produced by non-anodic stain etching of p-type (100) Si substrates is studied. The layers were characterized by transmission electron microscopy as being amorphous in nature. X-ray photoelectron spectroscopy and electron spin resonance measurements show these layers to be composed mainly of a-Si. The formation mechanism of the a-Si is explored using by stain etching SiGe ‘marker’ layers within epitaxially grown Si films and by high temperature annealing. These experiments provide strong evidence for a spontaneous crystalline-amorphous phase transformation during the etching process.
Functionalization of C60 has been achieved by [2+2] photocycloaddition reactions of enones and [2+4] cycloaddition reactions of dienes, the course of these reactions can be followed using electrospray mass spectrometry using a special tagging reagent. Using tagged C60 it was shown that cis and trans cycloadducts are formed from ketones such as 3-methylcyclohexenone. We have also employed the new technique of 3He NMR spectrometry. 3He is an NMR-active nucleus. Fullerenes containing an endohedral 3He atom can be examined by NMR to obtain structural information and potentially determine isomer distributions. Examples, of helium spectra of fullerene hydrides are presented.
The relevance of lattice distortion, polaron conduction, and double-exchange interaction to the occurrence of colossal magnetoresistance (CMR) is investigated by comparing the physical properties of magnetoresistive manganites and cobaltites. The samples studied in this work include epitaxial films and ceramics of manganites with both A- and B-site substitution, (La0.7Ca0.3MnO3, LaMn0.7 Ni0.3O3, LaMnO.5Ni0.5O3), as well as epitaxial films and ceramics of cobaltites (La0.5Ca0.5CoO3). The structural, chemical, electrical transport, magnetic, optical properties and tunneling spectroscopy are studied. Based on our experimental results, we conclude that both double-exchange interaction and strong electron-phonon coupling due to the Jahn-Teller effect are essential to the occurrence of CMR.
We report the studies of the Hall effect and magnetic properties in La0.5Ca0.5CoO3 thin films and ceramics. We use the local Hall probe and SQUID magnetometers to measure the magnetization M of the samples. Both below and above the Curie temperature, the Hall resistivity pxy(H) is shown to be proportional to M(H) (H is the applied magnetic field). Thus, our results provide convincing evidence for the anomalous Hall effect in these cobaltites. The value of the anomalous Hall coefficient Rs in La0.5Ca0.5CoO3 significantly exceeds those of other known single-phase ferromagnetic metals. We suggest that the coexistence of high- and low-spin configurations in the perovskite cobaltites, which gives rise to magnetic percolation behavior in La1-xCax.CoO3,may be responsible for the giant Ra.
Stain films on Si wafers produced in solutions of HF:HNO3:H2O have been studied for over 30 years , and have been suggested  to be similar in nature to the anodically-etched porous Si films first demonstrated by Uhlir . More recently, it was shown that stain films produced by etching Si in solutions of NaNO2 in HF and CrO3 in HF were similar in structure to porous Si films produced by anodic etching . In fact, in the etching of Si by HF:HNO3:H3O solutions, the oxidation reaction chemistry is recognized to be the same as that of anodic oxidation, with points on the Si surface behaving randomly as localized anodes and cathodes