Analysis of body condition indices reveals different ecotypes of the Antillean manatee.

Assessing the body condition of wild animals is necessary to monitor the health of the population and is critical to defining a framework for conservation actions. Body condition indices (BCIs) are a non-invasive and relatively simple means to assess the health of individual animals, useful for addressing a wide variety of ecological, behavioral, and management questions. The Antillean manatee (Trichechus manatus manatus) is an endangered subspecies of the West Indian manatee, facing a wide variety of threats from mostly human-related origins. Our objective was to define specific BCIs for the subspecies that, coupled with additional health, genetic and demographic information, can be valuable to guide management decisions. Biometric measurements of 380 wild Antillean manatees captured in seven different locations within their range of distribution were obtained. From this information, we developed three BCIs (BCI1 = UG/SL, BCI2 = W/SL3, BCI3 = W/(SL*UG2)). Linear models and two-way ANCOVA tests showed significant differences of the BCIs among sexes and locations. Although our three BCIs are suitable for Antillean manatees, BCI1 is more practical as it does not require information about weight, which can be a metric logistically difficult to collect under particular circumstances. BCI1 was significantly different among environments, revealing that the phenotypic plasticity of the subspecies have originated at least two ecotypes-coastal marine and riverine-of Antillean manatees.

Global restoration opportunities in tropical rainforest landscapes.

Over 140 Mha of restoration commitments have been pledged across the global tropics, yet guidance is needed to identify those landscapes where implementation is likely to provide the greatest potential benefits and cost-effective outcomes. By overlaying seven recent, peer-reviewed spatial datasets as proxies for socioenvironmental benefits and feasibility of restoration, we identified restoration opportunities (areas with higher potential return of benefits and feasibility) in lowland tropical rainforest landscapes. We found restoration opportunities throughout the tropics. Areas scoring in the top 10% (i.e., restoration hotspots) are located largely within conservation hotspots (88%) and in countries committed to the Bonn Challenge (73%), a global effort to restore 350 Mha by 2030. However, restoration hotspots represented only a small portion (19.1%) of the Key Biodiversity Area network. Concentrating restoration investments in landscapes with high benefits and feasibility would maximize the potential to mitigate anthropogenic impacts and improve human well-being.

Percutaneous Sacroiliac Screw Technique.

Remembering that preoperative planning, surgical indications, and fracture reduction are paramount for this procedure, presented here is our technique for performing percutaneous sacroiliac screws, both transiliac-transsacral and sacral style. A combination of video, still pictures, and fluoroscopy images will guide the viewer through the process we routinely use highlighting specific details. Patient positioning and intraoperative fluoroscopy imaging are critical to a successful procedure. Although inlet and outlet films remain important, we find the procedure best started on the lateral sacral view to reduce the need for start site, trajectory, and imaging position changes during the case. A cannulated pig sticker (drill guide) used with long drill tip guide wires provide improved manual control to both finding a good start site and directing the trajectory. For patient safety, sacral anatomy and safe zones are discussed as well. Using these technical points will help make this a successful procedure.

Seed dispersal limitations shift over time in tropical forest restoration.

Past studies have shown that tropical forest regeneration on degraded farmlands is initially limited by lack of seed dispersal, but few studies have tracked changes in abundance and composition of seed rain past the first few years after land abandonment. We measured seed rain for 12 months in 10 6-9-year-old restoration sites and five mature, reference forests in southern Costa Rica in order to learn (1) if seed rain limitation persists past the first few years of regeneration; (2) how restoration treatments influence seed community structure and composition; and (3) whether seed rain limitation is contingent on landscape context. Each restoration site contained three 0.25-ha treatment plots: (1) a naturally regenerating control, (2) tree islands, and (3) a mixed-species tree plantation. Sites spanned a deforestation gradient with 9-89% forest area within 500 m around the treatment plots. Contrary to previous studies, we found that tree seeds were abundant and ubiquitous across all treatment plots (585.1 ± 142.0 seeds · m(-2) · yr(-1) [mean ± SE]), indicating that lack of seed rain ceased to limit forest regeneration within the first decade of recovery. Pioneer trees and shrubs comprised the vast majority of seeds, but compositional differences between restoration sites and reference forests were driven by rarer, large-seeded species. Large, animal-dispersed tree seeds were more abundant in tree islands (4.6 ± 2.9 seeds · m(-2) · yr(-1)) and plantations (5.8 ± 3.0 seeds · m(-2) · yr(-1)) than control plots (0.2 ± 0.1 seeds · m(-2) · yr(-1)), contributing to greater tree species richness in actively restored plots. Planted tree species accounted for < 1% of seeds. We found little evidence for landscape forest cover effects on seed rain, consistent with previous studies. We conclude that seed rain limitation shifted from an initial, complete lack of tree seeds to a specific limitation on large-seeded, mature forest species over the first decade. Although total seed abundance was equal among restoration treatments, tree plantations and tree islands continued to diversify seed rain communities compared to naturally regenerating controls. Compositional differences between regenerating plots and mature forests suggest that large-seeded tree species are appropriate candidates for enrichment planting.

Landscape context mediates avian habitat choice in tropical forest restoration.

Birds both promote and prosper from forest restoration. The ecosystem functions birds perform can increase the pace of forest regeneration and, correspondingly, increase the available habitat for birds and other forest-dependent species. The aim of this study was to learn how tropical forest restoration treatments interact with landscape tree cover to affect the structure and composition of a diverse bird assemblage. We sampled bird communities over two years in 13 restoration sites and two old-growth forests in southern Costa Rica. Restoration sites were established on degraded farmlands in a variety of landscape contexts, and each included a 0.25-ha plantation, island treatment (trees planted in patches), and unplanted control. We analyzed four attributes of bird communities including frugivore abundance, nectarivore abundance, migrant insectivore richness, and compositional similarity of bird communities in restoration plots to bird communities in old-growth forests. All four bird community variables were greater in plantations and/or islands than in control treatments. Frugivore and nectarivore abundance decreased with increasing tree cover in the landscape surrounding restoration plots, whereas compositional similarity to old-growth forests was greatest in plantations embedded in landscapes with high tree cover. Migrant insectivore richness was unaffected by landscape tree cover. Our results agree with previous studies showing that increasing levels of investment in active restoration are positively related to bird richness and abundance, but differences in the effects of landscape tree cover on foraging guilds and community composition suggest that trade-offs between biodiversity conservation and bird-mediated ecosystem functioning may be important for prioritizing restoration sites.

Testing heterogeneity-diversity relationships in tropical forest restoration.

Restoring small-scale habitat heterogeneity in highly diverse systems, like tropical forests, is a conservation challenge and offers an excellent opportunity to test factors affecting community assembly. We investigated whether (1) the applied nucleation restoration strategy (planting tree islands) resulted in higher habitat heterogeneity than more homogeneous forest restoration approaches, (2) increased heterogeneity resulted in more diverse tree recruitment, and (3) the mean or coefficient of variation of habitat variables best explained tree recruitment. We measured soil nutrients, overstory and understory vegetation structure, and tree recruitment at six sites with three 5- to 7-year-old restoration treatments: control (no planting), planted tree islands, and conventional, mixed-species tree plantations. Canopy openness and soil base saturation were more variable in island treatments than in controls and plantations, whereas most soil nutrients had similar coefficients of variation across treatments, and bare ground was more variable in control plots. Seedling and sapling species density were equivalent in plantations and islands, and were substantially higher than in controls. Species spatial turnover, diversity, and richness were similar in island and plantation treatments. Mean canopy openness, rather than heterogeneity, explained the largest proportion of variance in species density. Our results show that, whereas canopy openness and soil base saturation are more heterogeneous with the applied nucleation restoration strategy, this pattern does not translate into greater tree diversity. The lack of a heterogeneity-diversity relationship is likely due to the fact that recruits respond more strongly to mean resource gradients than variability at this early stage in succession, and that seed dispersal limitation likely reduces the available species pool. Results show that planting tree islands facilitates tree recruitment to a similar degree as intensive plantation-style restoration strategies.

Antimicrobial prescription and usage in the neonatal intensive care units of a Caribbean country: a prospective observational study.

OBJECTIVE: To study the prescribing patterns and usage of antimicrobials in the Neonatal Intensive Care Units (NICU) of Trinidad & Tobago. METHODS: A 3-month prospective observational study was conducted at the three NICUs at the major public hospitals. Data included antimicrobials prescribed, route of administration, culture and sensitivity reports, leukocyte count, length of stay and outcome of patients. RESULTS: 353 patients were studied, 57.5% of the patients were males. Mean birth weight was 2.96 ± 0.94 (Standard Deviation) kg. Admission diagnoses included meconium stained liquor, preterm, respiratory distress, sepsis, etc. Length of stay ranged between 1 to 76 days, (median 4, Interquartile Range 1-8). The mean leukocyte count was 15.7 ± 8.5 × 103 per µL. Overall, 645 culture specimens were sent; umbilical swab (27.6%), throat swab (27.0%) and blood (16.4%) being the most common specimens. 310 (48.1%) showed no bacterial growth. Overall, 16 different antimicrobials were used. First line antibiotic of choice was a combination of ampicillin and gentamicin (85.8 %). Second line antibiotic of choice was cefotaxime. The overall mortality was 7.6%. CONCLUSION: The choice of antimicrobials in the NICUs of major public hospitals is mostly empirical and not primarily dictated by the culture and sensitivity reports, emphasizing the need for antibiotic stewardship programme in Trinidad & Tobago.

The role of exo-(1-->4)-beta-galactanase in the mobilization of polysaccharides from the cotyledon cell walls of Lupinus angustifolius following germination.

BACKGROUND AND AIMS: The cotyledons of Lupinus angustifolius contain large amounts of cell wall storage polysaccharide (CWSP) composed mainly of (1-->4)-beta-linked D-galactose residues in the form of branches attached to a rhamnogalacturonan core molecule. An exo-(1-->4)-beta-galactanase with a very high specificity towards (1-->4)-beta-linked D-galactan has been isolated from L. angustifolius cotyledons, and shown to vary (activity and specific protein) in step with CWSP mobilization. This work aimed to confirm the hypothesis that galactan is the main polymer retrieved from the wall during mobilization at the ultrastructural level, using the purified exo-galactanase as a probe. METHODS: Storage mesophyll cell walls ('ghosts') were isolated from the cotyledons of imbibed but ungerminated lupin seeds, and also from cotyledons of seedlings after the mobilization of the CWSP. The pure exo-(1-->4)-beta-galactanase was coupled to colloidal gold particles and shown to be a specific probe for (1-->4)-beta-D-galactan. They were used to localize galactan in ultrathin sections of L. angustifolius cotyledonary mesophyll tissue during CWSP mobilization. KEY RESULTS: On comparing the morphologies of isolated cell walls, the post-mobilization 'ghosts' did not have the massive wall-thickenings of pre-mobilization walls. Compositional analysis showed that the post-mobilization walls were depleted in galactose and, to a lesser extent, in arabinose. When pre-mobilization ghosts were treated with the pure exo-galactanase, they became morphologically similar to the post-mobilization ghosts. They were depleted of approximately 70% of the galactose residues that would have been mobilized in vivo, and retained all the other sugar residues originally present. Sharply defined electron-transparent wall zones or pockets are associated with CWSP mobilization, being totally free of galactan, whereas wall areas immediately adjacent to them were apparently undepleted. CONCLUSIONS: The exo-(1-->4)-beta-galactanase is the principal enzyme involved in CWSP mobilization in lupin cotyledons in vivo. The storage walls dramatically change their texture during mobilization as most of the galactan is hydrolysed during seedling development.

Pesticide exposure in a farming village in Venezuela--a developing country.

This study was designed and performed by the Universidad de Carabobo, Centro de Investigaciones Toxicológicas, Venezuela, and the University of Cincinnati Department of Environmental Health. The authors tested methodology and analyzed preliminary data on demographics, pesticide use, health, environment, and lifestyles in a farming community in Venezuela (population = 386; sample size = 81) to determine if pesticide misuse might have been contributing to public health problems. Questionnaire and geographic information were collected. There were statistically significant incidences of pesticide-related symptoms (p < .01) in farmers versus nonfarmers (odds ratio = 5.7; 95% confidence interval = 2.9, 18.8). In addition, in one area there was a cluster of farmers who experienced symptoms that appeared to be the result of foul air and proximity to farms where there was pesticide use. The results of the study indicated that this public health problem may have been associated with pesticide misuse; however, additional studies are needed to corroborate the findings.

A new family of oligosaccharides from the xyloglucan of Hymenaea courbaril L. (Leguminosae) cotyledons.

The xyloglucan from cotyledons of Hymenaea courbaril was hydrolysed with endo-(1,4)-beta-D-glucanase (cellulase) and analysed by TLC and HPAEC. The limit digest was different from those obtained from xyloglucans of Tamarindus indica and Copaifera langsdorffii. On treatment with nasturtium beta-galactosidase, two main oligosaccharides were detected by TLC and HPAEC. Using a process of enzymatic sequencing involving alternate treatments with a pure xyloglucan oligosaccharide-specific alpha-xylosidase, and a pure beta-glucosidase, both from nasturtium, their structures were deduced to be XXXG and a new oligosaccharide XXXXG. These structures were confirmed by 1H NMR. The relative proportions of XXXG and XXXXG indicate that approximately half of the subunits in Hymenaea xyloglucan are based on the new oligosaccharides. In the native polymer the XXXXG subunits are likely to carry galactosyl substituents in varying proportions, since cellulase hydrolysates contained many bands which were converted to XXXXG on hydrolysis with nasturtium beta-galactosidase. Although no comparative studies on the physico-chemical properties of Hymenaea courbaril xyloglucan have yet been performed, our results indicate that this polymer is less interactive with iodine when compared with T. indica and C. langsdorffii xyloglucans, suggesting that changes in conformation may occur due to the presence of XXXXG.

Studies on ultrasonic scattering from quasi-periodic structures.

This study extends the work done on nonuniform phase statistics by including additional results based on quasi-periodic scattering. Three parameters are used to predict the presence of regular structure within the region of interest. The signal-to-noise ratio of phase and the chi (2) statistic resulting from conducting a goodness of fit test are two parameters used to verify whether the phase signal followed a uniform distribution. A third parameter, the power spectral density (PSD), was studied and its ability to provide information on the level of periodicity present was analyzed. Computer simulations and experiments on tissue mimicking phantoms were carried out, the results of which indicate that the parameters introduced in this paper have good potential in providing a better understanding of scattering from a collection of quasi-periodic scatterers.

On modeling the tissue response from ultrasonic B-scan images.

The authors model tissue as a collection of point scatterers embedded in a uniform media, and show that the higher-order statistics (HOS) of the scatterer spacing distribution can be estimated from digitized radio frequency (RF) scan line segments and be used in obtaining tissue signatures. The authors assume that RF echoes are non-Gaussian, on the grounds of empirical/theoretical justifications presented in the literature. Based on their model for tissue microstructure, the authors develop schemes for the estimation of reasonable periodicity as well as correlations among nonperiodic scatterers, Using HOS of the scattered signal, the authors define as tissue "color" a quantity that describes the scatterer spatial correlations, show how to evaluate it from the higher-order correlations of the digitized RF scan line segments, and investigate its potential as a tissue signature. The tools employed, i.e., HOS, were chosen as the most appropriate ones because they suppress Gaussian processes, such as the one arising from the diffused scatterers. HOS, unlike second-order statistics, also preserve the Fourier-phase of the signature, the color of the tissue response. Working on simulated and clinical data, the authors show that the proposed periodicity estimation technique is superior to the widely used power spectrum and cepstrum techniques in terms of the accuracy of estimations. The authors also show that even when there is no significant periodicity in data, they are still able to characterize tissues using signatures based on the higher-order cumulant structure of the scatterer spacing distribution.

Control of larval Aedes aegypti (Diptera: Culicidae) by cyclopoid copepods in peridomestic breeding containers.

Mesocyclops longisetus (Thiébaud), Mesocyclops thermocyclopoides Harada, Mesocyclops venezolanus Dussart, and Macrocyclops albidus (Jurine) were tested for their effectiveness in controlling Aedes aegypti (L.) larvae in a variety of containers around homes in El Progreso, Honduras. All four cyclopoid species killed > 20 larvae per cyclopoid per d under container conditions. M. longisetus was most effective, not only because it was the most voracious predator, but also because it survived best in the containers. M. longisetus maintained long-term populations in 200-liter drums, tires, vases, and cement tanks (without drains), providing the cyclopoids were not dried or poured out. M. longisetus reduced third- and fourth-instar Ae. aegypti larvae by > 98% compared with control containers without cyclopoids. M. longisetus should be of practical value for community-based Ae. aegypti control if appropriate attention is directed to maintaining it in containers after introduction.

Non-Rayleigh statistics of ultrasonic backscattered signals.

The statistics of the envelope of the backscattered signal from tissues have been known to vary from the well-known Rayleigh model. The K-distribution is used to model this non-Rayleigh behavior, since the generalized K-distribution encompasses a wide range of distributions like Rayleigh, Lognormal, and Rician. Computer simulations were conducted using a simple one-dimensional discrete scattering model to investigate the properties of the echo envelope. Significant departures from Rayleigh statistics were seen as the scattering cross sections of the scatterers became random. The validity of this model was also tested using data from tissue mimicking phantoms. Results indicate that the density function of the envelope can be modeled by the K-distribution and the parameters of the K-distribution can provide information on the nature of the scattering region in terms of the number as well as the scattering cross sections of the scatterers.

Use of non-Rayleigh statistics for the identification of tumors in ultrasonic B-scans of the breast.

A model for the scattering of ultrasound from breast tissue is proposed. The model is based on the use of non-Rayleigh statistics, specifically the K distribution to describe the backscattered echo from the tissue. A multiparameter test based on this model has been designed to characterize the tissue. The data from the B-scan images of the breasts of 6 different patients were analyzed using this model. The results indicate that the non-Rayleigh statistics seem to be useful in characterizing and identifying malignant, benign, and normal tissue regions.

Nonuniform phase distribution in ultrasound speckle analysis. I. Background and experimental demonstration.

In some cases, the statistical properties of the phase of ultrasound speckle in B-scan images differ from the uniform distribution characteristic exhibited by the fully developed speckle. This phenomenon has been noted when examining scattering structures with a somewhat regular spacing using wideband pulse excitation. It is shown by computer simulation and experiments on phantoms that when the mean scatterer spacing is equal to multiples of a half wavelength at the reference frequency of the receiver quadrature demodulator, the center of the echo phase distribution, plotted on the complex plane, will shift away from the origin. When the spacing is equal to an odd multiple of a quarter wavelength, the phase distribution will have a figure ;8' shape. By noticing those noncircular phase distributions while changing the demodulation frequency, the mean scatterer spacing can be estimated.

Nonuniform phase distribution in ultrasound speckle analysis. II. Parametric expression and a frequency sweeping technique to measure mean scatterer spacing.

For pt.I see ibid., vol.39, no.3, p.352-9 (1992). The existence of regularly spaced scatterers in the range cell of an ultrasonic imaging system results in speckle with a nonuniform phase distribution. Characteristic phase distributions occur at those particular demodulator frequencies at which the spacing is a multiple of one-quarter wavelength. A demodulator frequency sweeping technique for scatterer spacing estimation has been developed that uses parametric expressions of the phase statistics to detect and to identify scatterers with regular spacings. Changes in these parameters separately identify the mean scatterer spacing when it is an even and an odd multiple of the quarter wavelength of the demodulator frequency. This technique has good tolerance for variations in mean scatterer spacing, and has real-time implementation capability.

Diminuiçäo das respostas vascular e adrenal à angiotensina II após a administaçäo de nifedipina / Decrease of vascular response to angiotensin II after nifedipine administration

O efeito da nifedipina sobre a resposta pressórica e sobre a aldosterona em relaçäo à angiotensina II e sobre a inibiçäo da liberaçäo de renina pela angiotensiva II foi examinado em dois estudos. No primeiro, seis indivíduos normais com equilíbrio salino normal receberam duas infusöes graduadas de angiotensina II a 5, 10 e 20 ng/kg/min em cada um dos dois dias de estudo . Num dia, a nifedipina (20 mg) foi administrada entre as infusöes e no dia controle näo foi administrado tratamento. No segundo estudo, sete indivíduos receberam nifedipina (10 mg) três vezes ao dia durante três dias. No quarto dia, após a dose matinal de nifedipina, a angiotensina II foi infundida a 2,5 e 20 ng/kg/min, seguida após uma hora por uma infusäo de noradrenalina a 50-500 ng/kg/min. Numa outra ocasiäo a experiência foi repetida sem a administraçäo da nifedipina. A nifedipina causou uma atenuaçäo significativa nas respostas pressóricas em ambos estudos, manifestada como uma alteraçäo para a direita nas curvas logarítmicas dose-resposta. O efeito pressórico da noradrenalina foi atenuado da mesma forma. As respostas de aldosterona à angiotensiva II foram significativamente diminuídas após uma única dose de nifedipina, mas näo após três dias de tratamento. A renina foi suprimida de modo dose-dependente durante a infusäo de angiotensina II e estimulada quadruplamente pela nifedipina. Níveis estimulados também foram suprimidos pela angiotensina II. Estes achados sugerem que a nifedipina pode diminuir a pressäo sangüínea diminuindo o grau de resposta vascular a hormônios pressóricos e respostas adrenais à angiotensina II e que a liberaçäo de aldosterona, mas näo a inibiçäo da liberaçäo da renina pela angiotensina II, é dependente da entrada de cálcio nas células