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Growing demand for pesticides has created an environment prone to deceptive activities, where counterfeit or adulterated pesticide products infiltrate the market, often escaping rapid detection. This situation presents a significant challenge for sensor technology, crucial in identifying authentic pesticides and ensuring agricultural safety practices. Raman spectroscopy emerges as a powerful technique for detecting adulterants. Coupling the electrochemical techniques allows a more specific and selective detection and compound identification. In this study, we evaluate the efficacy of spectroelectrochemical measurements by coupling a potentiostat and Raman spectrograph to identify paraquat, a nonselective herbicide banned in several countries. Our findings demonstrate that applying -0.70 V during measurements yields highly selective Raman spectra, highlighting the primary vibrational bands of paraquat. Moreover, the selective Raman signal of paraquat was discernible in complex samples, including tap water, apple, and green cabbage, even in the presence of other pesticides such as diquat, acephate, and glyphosate. These results underscore the potential of this technique for reliable pesticide detection in diverse and complex matrices.

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The indiscriminate use of pesticides makes us susceptible to the toxicity of these chemical compounds, which may be present in high quantities in our food. It is crucial to develop inexpensive and rapid methods for determining these pesticides for government control or even for the general population. In this study, we investigated the fabrication of self-assembled LbL films using multi-walled carbon nanotubes (MWCNT) and nickel tetrasulphonated phthalocyanine (NiTsPc) as an electrochemical sensor for the herbicide Diquat (DQ). The Layer-by-Layer (LbL) assembly of the (MWCNT/NiTsPc) film was examined, along with its structural and morphological characteristics. The effect of the number of layers in DQ detection was evaluated by cyclic voltammetry, followed by the detection through differential pulse voltammetry. The achieved limit of detection was 9.62 × 10-7 mol L-1. A ~ 30% decrease in sensitivity was observed in the presence of Paraquat, a banned herbicide and electrochemical interferent due to the structural similarities, which is regularly neglected in the most published studies. The sensor was tested in real samples, demonstrating a recovery of 98.5% in organic apples.

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The potentially toxic effects of emerging pollutant mixtures often deviate from the individual compound effects, presenting additive, synergistic, or agonistic interactions. This study delves into the complex world of emerging pollutants' mixtures, with a particular focus on their potential impact on unsaturated lipid DOPC (1,2-dioleoyl-sn-glycerol-3-phosphocholine) structured as both monolayers and bilayers, which are valuable tools for mimicking cell membranes. Specifically, we examine the effects of two common types of pollutants: antibiotics (amoxicillin) and dyes (methylene blue). Utilizing Langmuir monolayers, our research reveals a synergistic effect within the pollutant mixture, as evidenced by pressure-area isotherms and polarization-modulated infrared reflection absorption spectroscopy. We identify the specific chemical interactions contributing to this synergistic effect. Furthermore, through contrast phase microscopy experiments on giant unilamellar vesicles (bilayer system), we find that the individual pollutants and the mixture exhibit similar molecular effects on the bilayer, revealing that the molecular size is a key factor in the bilayer-mixture of pollutant interaction. This highlights the importance of considering molecular size in the interactions with bilayer systems. In summary, our research dissects the critical factors of chemical interactions and molecular size concerning the effects of pollutants on DOPC, serving as simplified models of cell membranes. This study underscores the significance of comprehending the molecular effects of emerging pollutants on human health and the development of models for exploring their intricate interactions with cell membranes.

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Improving the performance of thin film-based devices is a crucial factor for their successful application, mainly for organic electronic semiconductors. The adjustment of supramolecular structuring of thin films plays a role in the optical and electrical properties. In this sense, we investigated how various pH values, such as 2.5, 6.0, and 9.0, of the solutions influenced the growth of iron tetrasulfonated phthalocyanine (FeTsPc) Layer-by-Layer (LbL) films and their respective supramolecular structures as well as their electrochemical properties. The supramolecular structures were evaluated via UV-vis absorption spectroscopy, quartz crystal microbalance (QCM), micro-Raman spectroscopy, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and cyclic voltammetry. The different pH values of the solution induce different degrees of molecular aggregation for FeTsPc (monomer, dimer, and aggregate formation). For instance, the higher the pH, the higher the aggregation. Films produced at pH 2.5 were organized preferentially with the molecules perpendicular to the substrate, while films at pH 6.0 and 9.0 were organized preferentially with the molecules parallel to the substrate. Besides, the film produced at pH 2.5 results in higher film thickness, higher stability, and better electrocatalytic behavior for the electrochemical detection of catechol. The results presented here enhance the understanding of nanostructured films, helping to harness supramolecular organization to improve the performance of thin-film devices.

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Bioeroding sponges can cause extensive damage to aquaculture and wild shellfish fisheries. It has been suggested that heavy sponge infestations that reach the inner cavity of oysters may trigger shell repair and lead to adductor detachment. Consequently, energy provision into shell repair could reduce the energy available for other physiological processes and reduce the meat quality of commercially fished oysters. Nevertheless, the impacts of boring sponges on oysters and other shellfish hosts are inconclusive. We studied the interaction between boring sponges and their hosts and examined potential detrimental effects on an economically important oyster species Ostrea chilensis from Foveaux Strait (FS), New Zealand. We investigated the effect of different infestation levels with the bioeroding sponge Cliona sp. on commercial meat quality, condition, reproduction, and disease susceptibility. Meat quality was assessed with an index based on visual assessments used in the FS O. chilensis fishery. Meat condition was assessed with a common oyster condition index, while histological methods were used to assess sex, gonad stage, reproductive capacity, and pathogen presence. Commercial meat quality and condition of O. chilensis were unaffected by sponge infestation. There was no relationship between sex ratio, gonad developmental stage, or gonad index and sponge infestation. Lastly, we found no evidence that sponge infestation affects disease susceptibility in O. chilensis. Our results suggest that O. chilensis in FS is largely unaffected by infestation with Cliona sp. and therefore reinforces the growing body of evidence that the effects of sponge infestation can be highly variable among different host species, environments, and habitats.

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Long-term studies on the population dynamics of tropical resident birds are few, and it remains poorly understood how their populations have fared in recent decades. Here, we analyzed a 44-y population study of a Neotropical understory bird assemblage from a protected forest reserve in central Panama to determine if and how populations have changed from 1977 to 2020. Using the number of birds captured in mist nets as an index of local abundance, we estimated trends over time for a diverse suite of 57 resident species that comprised a broad range of ecological and behavioral traits. Estimated abundances of 40 (∼70%) species declined over the sampling period, whereas only 2 increased. Furthermore, declines were severe: 35 of the 40 declining species exhibited large proportional losses in estimated abundance, amounting to ≥50% of their initial estimated abundances. Declines were largely independent of ecology (i.e., body mass, foraging guild, or initial abundance) or phylogenetic affiliation. These widespread, severe declines are particularly alarming, given that they occurred in a relatively large (∼22,000-ha) forested area in the absence of local fragmentation or recent land-use change. Our findings provide robust evidence of tropical bird declines in intact forests and bolster a large body of literature from temperate regions suggesting that bird populations may be declining at a global scale. Identifying the ecological mechanisms underlying these declines should be an urgent conservation priority.

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Size, growth, and density have been studied for North American Pacific coast sea urchins Strongylocentrotus purpuratus, S. droebachiensis, S. polyacanthus, Mesocentrotus (Strongylocentrotus) franciscanus, Lytechinus pictus, Centrostephanus coronatus, and Arbacia stellata by various workers at diverse sites and for varying lengths of time from 1956 to present. Numerous peer-reviewed publications have used some of these data but some data have appeared only in graduate theses or the gray literature. There also are data that have never appeared outside original data sheets. Motivation for studies has included fisheries management and environmental monitoring of sewer and power plant outfalls as well as changes associated with disease epidemics. Studies also have focused on kelp restoration, community effects of sea otters, basic sea urchin biology, and monitoring. The data sets presented here are a historical record of size, density, and growth for a common group of marine invertebrates in intertidal and nearshore environments that can be used to test hypotheses concerning future changes associated with fisheries practices, shifts of predator distributions, climate and ecosystem changes, and ocean acidification along the Pacific Coast of North America and islands of the north Pacific. No copyright restrictions apply. Please credit this paper when using the data.

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ABSTRACT Objective: To determine physical activity levels of community dwelling persons with spinal cord injury (SCI) who received inpatient rehabilitation at the Sir John Golding Rehabilitation Centre (SJGRC). This study also explored the perceived barriers to exercise and the development of secondary health complications. Methods: A non-experimental cross-sectional analysis of relationships was done. Participants were recruited from the SJGRC discharge files. Three questionnaires (The Physical Activity and Disability Scale, Spinal Cord Injury Secondary Conditions Scale and the Barriers to Exercise and Disability Scale) were administered via a telephone interview. Results: Only 58.3% of patients were engaged in some form of exercise and of that amount only 6% engaged in vigorous exercise. The main secondary conditions affecting both persons with paraplegia and quadriplegia were spasticity, chronic, muscle and joint pain. There were no significant differences between persons having paraplegia and quadriplegia in relation to physical activity levels, development of secondary conditions or barriers to exercise. Most persons were interested in an exercise programme but the most common barriers to exercise were cost and not knowing where they could go to exercise. Conclusion: Regardless of injury level, persons with spinal cord injury living in their communities in Jamaica are not engaged in adequate levels of exercise to confer health benefits and aid with healthy ageing. Barriers like cost, availability and accessibility of facilities must be addressed if this situation is to improve.

RESUMEN Objetivo: Determinar los niveles de actividad física de las personas con lesión de la médula espinal (LME) que viven en sus comunidades -es decir, en sus casas en vez de asilos o instituciones asistenciales-y que recibieron rehabilitación hospitalaria en el Centro de Rehabilitación Sir John Golding (SJGRC, en inglés). Este estudio también exploró las barreras percibidas para hacer ejercicios, y el desarrollo de complicaciones secundarias de salud. Métodos: Se realizó un análisis transversal no experimental de las relaciones. Los participantes fueron reclutados a partir de los archivos de altas del Centro SJGRC. Se aplicaron tres cuestionarios mediante entrevista telefónica (Escala de Actividad Física y Discapacidad, Escala de Condiciones Secundarias de la Lesión Medular, y Escala de Discapacidad y Barreras al Ejercicio). Resultados: Sólo el 58.3% de los pacientes se hallaban participando en alguna forma de ejercicio, y de este número sólo el 6% practicaba ejercicios fuertes. Las condiciones secundarias principales que afectaban a ambas personas con paraplejia y cuadriplejia eran la espasticidad, y el dolor muscular y articular crónico. No había diferencias significativas entre las personas que tenían paraplejia y cuadriplejia en lo referente a los niveles de actividad física, el desarrollo de condiciones secundarias o las barreras al ejercicio. La mayoría de las personas estaban interesadas en un programa de ejercicios, pero las barreras más comunes eran el costo y el no saber dónde ir a hacerlos. Conclusión: Independientemente del nivel de la lesión, las personas con lesión medular que viven en sus comunidades en Jamaica no participan en niveles adecuados de ejercicio que brinden beneficios de salud y ayuden a un envejecimiento saludable. Las barreras como el costo, la disponibilidad y la accesibilidad de las instalaciones deben ser abordadas, si se quiere mejorar esta situación.

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Prostate cancer is the third leading cause of cancer death among men worldwide and is the leading cause of cancer mortality in males greater than 60 years in Trinidad and Tobago. Although there are some treatment options for the metastatic disease, the impact on overall survival rate has not improved in the last two decades. In particular, the mortality rate from prostate cancer is high among men of African descent in Trinidad and Tobago and the Americas. These groups manifest aggressive cancers that are often less responsive to available therapies. We hypothesize that phytochemical screening of tropical plants, coupled to cell culture studies would identify other potential treatments for prostate cancer. In separate experiments, the roots or leaves of five plants indigenous to the Caribbean and the skin of the muscadine grape, indigenous to North America were dried, crushed and suspended in 100% methanol. The respective methanol extracts were fractionated and the fractions dried. Next the ability of the extracts to halt the growth of or kill PC-3 prostate cancer cells was assessed by MTT assays. Colony formation, cell migration studies, cell cycle studies and western blots were performed to determine probable mechanism of action. The categories of chemical compounds present in the extracts were determined by Thin Layer chromatography (TLC). Results from MTT assays showed that compared to the control cells (ie those treated with DMSO only), treatment with at least four plant extracts significantly (p<0.05) inhibited the growth of the cancer cells; decreases as large as 95 % were observed. On the other hand these extracts had a limited or delayed effect on the "normal" PNT1A cells. Results from the cell cycle assay demonstrated that one extract, now identified as plant-A extract, caused the arrest of the G1/S phase of PC-3 cells i.e. leading to an increase in the number of cells that remained in the growth phase. On the other hand the total ethanol extract of muscadine grape skin decreased the expression of heat shock protein-40, possibly causing deactivation of the androgen receptor. This suggests that extracts prepared from Plant A and the muscadine grape have the potential for use as anticancer drugs.

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Prostate cancer is the third leading cause of cancer death among men worldwide and is the leading cause of cancer mortality in males greater than 60 years in Trinidad and Tobago. Although there are some treatment options for the metastatic disease, the impact on overall survival rate has not improved in the last two decades. In particular, the mortality rate from prostate cancer is high among men of African descent in Trinidad and Tobago and the Americas. These groups manifest aggressive cancers that are often less responsive to available therapies. We hypothesize that phytochemical screening of tropical plants, coupled to cell culture studies would identify other potential treatments for prostate cancer. In separate experiments, the roots or leaves of five plants indigenous to the Caribbean and the skin of the muscadine grape, indigenous to North America were dried, crushed and suspended in 100% methanol. The respective methanol extracts were fractionated and the fractions dried. Next the ability of the extracts to halt the growth of or kill PC-3 prostate cancer cells was assessed by MTT assays. Colony formation, cell migration studies, cell cycle studies and western blots were performed to determine probable mechanism of action. The categories of chemical compounds present in the extracts were determined by Thin Layer chromatography (TLC). Results from MTT assays showed that compared to the control cells (ie those treated with DMSO only), treatment with at least four plant extracts significantly (p<0.05) inhibited the growth of the cancer cells; decreases as large as 95 % were observed. On the other hand these extracts had a limited or delayed effect on the "normal" PNT1A cells. Results from the cell cycle assay demonstrated that one extract, now identified as plant-A extract, caused the arrest of the G1/S phase of PC-3 cells i.e. leading to an increase in the number of cells that remained in the growth phase. On the other hand the total ethanol extract of muscadine grape skin decreased the expression of heat shock protein-40, possibly causing deactivation of the androgen receptor. This suggests that extracts prepared from Plant A and the muscadine grape have the potential for use as anticancer drugs.

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Animals eavesdrop on other species to obtain information about their environments. Heterospecific eavesdropping can yield tangible fitness benefits by providing valuable information about food resources and predator presence. The ability to eavesdrop may therefore be under strong selection, although extensive research on alarm-calling in avian mixed-species flocks has found only limited evidence that close association with another species could select for innate signal recognition. Nevertheless, very little is known about the evolution of eavesdropping behaviour and the mechanism of heterospecific signal recognition, particularly in other ecological contexts, such as foraging. To understand whether heterospecific eavesdropping was an innate or learned behaviour in a foraging context, we studied heterospecific signal recognition in ant-following birds of the Neotropics, which eavesdrop on vocalizations of obligate ant-following species to locate and recruit to swarms of the army ant Eciton burchellii, a profitable food resource. We used a playback experiment to compare recruitment of ant-following birds to vocalizations of two obligate species at a mainland site (where both species are present) and a nearby island site (where one species remains whereas the other went extinct approx. 40 years ago). We found that ant-following birds recruited strongly to playbacks of the obligate species present at both island and mainland sites, but the island birds did not recruit to playbacks of the absent obligate species. Our results strongly suggest that (i) ant-following birds learn to recognize heterospecific vocalizations from ecological experience and (ii) island birds no longer recognize the locally extinct obligate species after eight generations of absence from the island. Although learning appears to be the mechanism of heterospecific signal recognition in ant-following birds, more experimental tests are needed to fully understand the evolution of eavesdropping behaviour.

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Previous reports of the haplosporidian parasite Bonamia ostreae have been restricted to the Northern Hemisphere, including Europe, and both eastern and western North America. This species is reported for the first time in New Zealand infecting the flat oyster Ostrea chilensis. Histological examination of 149 adult oysters identified 119 (79.9%) infected with Bonamia microcells. Bonamia generic PCR of several oysters followed by DNA sequencing of a 300 bp portion of the 18S rDNA gene produced a 100% match with that of B. ostreae. All DNA-sequenced products also produced a B. ostreae PCR-restriction fragment length polymorphism (PCR-RFLP) profile. Bonamia species-specific PCRs further detected single infections of B. exitiosa (2.7%), B. ostreae (40.3%), and concurrent infections (53.7%) with these 2 Bonamia species identifying overall a Bonamia prevalence of 96.6%. Detailed histological inspection revealed 2 microcell types. An infection identified by PCR as B. ostreae histologically presented small microcells (mean ± SE diameter = 1.28 ± 0.16 µm, range = 0.9-2 µm, n = 60) commonly with eccentric nuclei. A B. exitiosa infection exhibited larger microcells (mean ± SE diameter = 2.12 ± 0.27 µm, range = 1.5-4 µm, n = 60) with more concentric nuclei. Concurrent infections of both Bonamia species, as identified by PCR, exhibited both types of microcells. DNA barcoding of the B. ostreae-infected oyster host confirmed the identification as O. chilensis. A suite of other parasites that accompany O. chilensis are reported here for the first time in mixed infection with B. ostreae including apicomplexan X (76.5%), Microsporidium rapuae (0.7%) and Bucephalus longicornutus (30.2%).

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Nonindigenous apple snails, Pomacea maculata (formerly Pomacea insularum), are currently spreading rapidly through the southeastern United States. This mollusk serves as an intermediate host of the rat lungworm parasite (Angiostrongylus cantonensis), which can cause eosinophilic meningitis in humans who consume infected mollusks. A PCR-based detection assay was used to test nonindigenous apple snails for the rat lungworm parasite in Louisiana, Texas, Mississippi, and Florida. Only apple snails obtained from the New Orleans, Louisiana, area tested positive for the parasite. These results provide the first evidence that Angiostrongylus cantonensis does occur in nonindigenous apple snails in the southeastern United States. Additionally, Angiostrongylus cantonensis was identified in the terrestrial species Achatina fulica in Miami, Florida, indicating that rat lungworm is now established in Florida as well as Louisiana. Although the study suggests that the rat lungworm is not widespread in the Gulf States region, the infected snail population could still pose a risk to human health and facilitate the spread of the parasite to new areas.

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The purpose of this paper is to characterize the tiles placed on the walls of the Franciscan convent of "Santo Antônio" (Recife-PE) and to obtain information about the several expansions and structural reforms performed on the convent by dating the bricks. For this purpose, a portable energy dispersive x-ray fluorescence (EDXRF) was used to characterize the tiles. The dating of the bricks was performed using the Thermoluminescence (TL) technique. The results of the EDXRF analysis show that the dominant component of the white pigment is lead [2PbCO(3)·Pb(OH)(2)], used since the ancient times until the 20th century, while the dominant element of the blue pigment is cobalt (CoO·Al(2)O(3)), that has been used from 1807 until nowadays. The TL dating of bricks indicate that there were walls with different periods of construction, being one built around 1765, with a deviation of 28 years, whereas other was built later, around 1874, with a deviation of 15 years. These results provide new data towards understanding how and when the Recife Franciscan convent of "Santo Antônio" was designed and built, contributing to other research works presently underway on site.

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Plague disease caused by the gram-negative bacterium Yersinia pestis routinely affects animals and occasionally humans, in the western United States. The strains native to the North American continent are thought to be derived from a single introduction in the late 19(th) century. The degree to which these isolates have diverged genetically since their introduction is not clear, and new genomic markers to assay the diversity of North American plague are highly desired. To assay genetic diversity of plague isolates within confined geographic areas, draft genome sequences were generated by 454 pyrosequencing from nine environmental and clinical plague isolates. In silico assemblies of Variable Number Tandem Repeat (VNTR) loci were compared to laboratory-generated profiles for seven markers. High-confidence SNPs and small Insertion/Deletions (Indels) were compared to previously sequenced Y. pestis isolates. The resulting panel of mutations allowed clustering of the strains and tracing of the most likely evolutionary trajectory of the plague strains. The sequences also allowed the identification of new putative SNPs that differentiate the 2009 isolates from previously sequenced plague strains and from each other. In addition, new insertion points for the abundant insertion sequences (IS) of Y. pestis are present that allow additional discrimination of strains; several of these new insertions potentially inactivate genes implicated in virulence. These sequences enable whole-genome phylogenetic analysis and allow the unbiased comparison of closely related isolates of a genetically monomorphic pathogen.

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BACKGROUND AND AIMS: Little is known about the poststroke outcome in Caribbean populations. We investigated differences in the activities of daily living, level of social activities, living circumstances and survival for stroke patients in Barbados and London. METHODS: Data were collected from the South London Stroke Register and the Barbados Register of Strokes for patients with a first-ever stroke registered between January 2001 and December 2004. The ability to perform activities of daily living was measured by the Barthel Index and level of social activities by the Frenchay Activities Index. Living circumstances were categorised into private household vs. institutional care. Death and dependency, activities of daily living and social activities were assessed at three-months, one- and two-years using logistic regression, adjusted for differences in demographic, socioeconomic and stroke severity characteristics. RESULTS: At three-months, a high level of social activities was more likely for the Barbados Register of Strokes (odds ratio 1.84; 95% confidence interval 1.03-3.29); there were no differences in activities of daily living; and Barbados Register of Strokes patients were less likely to be in institutional care (relative risk ratio 0.38; 95% confidence interval 0.18-0.79). Following adjustment, Barbados Register of Strokes patients had a higher risk of mortality at three-months (relative risk ratio 1.85; 95% confidence interval 1.03-3.30), one-year (relative risk ratio 1.83; 95% confidence interval 1.08-3.09) and two-years (relative risk ratio 1.82; 95% confidence interval 1.08-3.07). This difference was due to early poststroke deaths; for patients alive at four-weeks poststroke, survival thereafter was similar in both settings. CONCLUSIONS: In Barbados, there was evidence for a healthy survivor effect, and short-term social activity was greater than that in the South London Stroke Register.

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Most [Caribbean] countries have grossly understaffed health promotion units, and while there are many initiatives, whether individual, non-governmental or governmental, they are often uncoordinated and unsustained. This chapter will review some of the broader Caribbean health promotion efforts in the literature and some of the local efforts in Barbados, and address the approaches most likely to have an impact on the major Caribbean health priorities.

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BACKGROUND: To compare health care utilisation between stroke patients living in a middle-income country with similar patients in a high-income country in terms of the type and amount of health care received following a stroke. METHODS: Data were collected from the population-based South London Stroke Register (SLSR) and the Barbados Register of Strokes (BROS) from January 2001 to December 2004. Differences in management and diagnostic procedures used in the acute phase were adjusted for age, sex, ethnic group, living conditions pre-stroke and socio-economic status by multivariable logistic regression. Comparison of subsequent management was made for 3 months and 1 year post-stroke. RESULTS: Patients in BROS were less likely to be admitted to a hospital ward (OR 0.22; 95% CI 0.13-0.37), but the difference for the lower use of brain scans in BROS was smaller (OR 0.62; 95% CI 0.25-1.52). Additional adjustment for stroke severity (Glasgow Coma Score) showed that BROS patients were more likely to have a swallow test on admission (OR 2.95; 95% CI 1.17-7.45). BROS patients were less likely to be in nursing care at 3 months (OR 0.37; 95% CI 0.17-0.81), and less likely to be receiving speech and language therapy at 3 months (OR 0.10; 95% CI 0.03-0.33) and 1 year (OR 0.05; 95% CI 0.00-0.55). CONCLUSIONS: The lower use of hospital admission and nursing care at 3 months suggests that in Barbados, family and friends take greater responsibility for patient care around the time of the stroke and in the medium term thereafter.

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