Disruption of an ant-plant mutualism shapes interactions between lions and their primary prey.

Mutualisms often define ecosystems, but they are susceptible to human activities. Combining experiments, animal tracking, and mortality investigations, we show that the invasive big-headed ant (Pheidole megacephala) makes lions (Panthera leo) less effective at killing their primary prey, plains zebra (Equus quagga). Big-headed ants disrupted the mutualism between native ants (Crematogaster spp.) and the dominant whistling-thorn tree (Vachellia drepanolobium), rendering trees vulnerable to elephant (Loxodonta africana) browsing and resulting in landscapes with higher visibility. Although zebra kills were significantly less likely to occur in higher-visibility, invaded areas, lion numbers did not decline since the onset of the invasion, likely because of prey-switching to African buffalo (Syncerus caffer). We show that by controlling biophysical structure across landscapes, a tiny invader reconfigured predator-prey dynamics among iconic species.

Demographic consequences of mutualism disruption: Browsing and big-headed ant invasion drive acacia population declines.

Across the globe, biological invasions have disrupted mutualisms, producing reverberating consequences for ecosystems. Although invasive species frequently trigger mutualism disruptions, few studies have quantified the demographic mechanisms by which mutualism breakdown may generate population effects. In a Kenyan savanna, the invasive big-headed ant (Pheidole megacephala) has disrupted a foundational mutualism between the monodominant whistling-thorn tree (Acacia drepanolobium) and native ants (Crematogaster spp.) that deter browsing by large mammalian herbivores. We conducted experiments to quantify the demographic consequences of this mutualism disruption in the presence and absence of large mammalian herbivores. Invasion by P. megacephala exacerbated population declines of A. drepanolobium, primarily through decreased survival and reproduction of adult trees. However, these fitness reductions were small compared to those resulting from the presence of large mammalian herbivores, which negatively impacted growth and survival. Contrary to expectation, the expulsion of metabolically costly Crematogaster mutualists by P. megacephala did not result in higher population growth rates for trees protected from large mammalian herbivores. Our results suggest that invasive P. megacephala may impose a direct metabolic cost to trees exceeding that of native mutualists while providing no protection from browsing by large mammalian herbivores. Across landscapes, we expect that invasion by P. megacephala will reduce A. drepanolobium populations, but that the magnitude and demographic pathways of this effect will hinge on the presence and abundance of browsers.

Density dependence and the spread of invasive big-headed ants (Pheidole megacephala) in an East African savanna.

Supercolonial ants are among the largest cooperative units in nature, attaining extremely high densities. How these densities feed back into their population growth rates and how abundance and extrinsic factors interact to affect their population dynamics remain open questions. We studied how local worker abundance and extrinsic factors (rain, tree density) affect population growth rate and spread in the invasive big-headed ant, which is disrupting a keystone mutualism between acacia trees and native ants in parts of East Africa. We measured temporal changes in big-headed ant (BHA) abundance and rates of spread over 20 months along eight transects, extending from areas behind the front with high BHA abundances to areas at the invasion front with low BHA abundances. We used models that account for negative density dependence and incorporated extrinsic factors to determine what variables best explain variation in local population growth rates. Population growth rates declined with abundance, however, the strength of density dependence decreased with abundance. We suggest that weaker density dependence at higher ant abundances may be due to the beneficial effect of cooperative behavior that partially counteracts resource limitation. Rainfall and tree density had minor effects on ant population dynamics. BHA spread near 50 m/year, more than previous studies reported and comparable to rates of spread of other supercolonial ants. Although we did not detect declines in abundance in areas invaded a long time ago (> 10 years), continued monitoring of abundance at invaded sites may help to better understand the widespread collapse of many invasive ants.

Moral Risk in the Behavior of Doctors of the Comprehensive Health Insurance in the Province of San Román, Puno-Peru, 2021.

Objective: The objective of the research was to determine which socioeconomic factors are the ones that most influence the moral hazard in the behavior of the doctors of the Comprehensive Health Insurance in the province of San Román and to identify the attitude of the doctor to a gift and its influence in moral hazard. Methods: The methodology used has a mixed, non-experimental and correlational approach, the Binomial Probit econometric model was used, applying a survey to 32 active doctors who work in the different SIS centers. Results: It is concluded that the factors that influenced the moral hazard and the behavior of the doctors were the bad reputation with a positive relation (27%), the social pressure with a negative relation (98%) and the behavioral attitude with a positive relation (94 %). Conclusion: Of the survey carried out, 40.6% of doctors reject the offer of a gift or bribe, reducing the influence of moral hazard by 94%.

Frenemy at the gate: Invasion by Pheidole megacephala facilitates a competitively subordinate plant ant in Kenya.

Biological invasions can lead to the reassembly of communities and understanding and predicting the impacts of exotic species on community structure and functioning are a key challenge in ecology. We investigated the impact of a predatory species of invasive ant, Pheidole megacephala, on the structure and function of a foundational mutualism between Acacia drepanolobium and its associated acacia-ant community in an East African savanna. Invasion by P. megacephala was associated with the extirpation of three extrafloral nectar-dependent Crematogaster acacia ant species and strong increases in the abundance of a competitively subordinate and locally rare acacia ant species, Tetraponera penzigi, which does not depend on host plant nectar. Using a combination of long-term monitoring of invasion dynamics, observations and experiments, we demonstrate that P. megacephala directly and indirectly facilitates T. penzigi by reducing the abundance of T. penzigi's competitors (Crematogaster spp.), imposing recruitment limitation on these competitors, and generating a landscape of low-reward host plants that favor colonization and establishment by the strongly dispersing T. penzigi. Seasonal variation in use of host plants by P. megacephala may further increase the persistence of T. penzigi colonies in invaded habitat. The persistence of the T. penzigi-A. drepanolobium symbiosis in invaded areas afforded host plants some protection against herbivory by elephants (Loxodonta africana), a key browser that reduces tree cover. However, elephant damage on T. penzigi-occupied trees was higher in invaded than in uninvaded areas, likely owing to reduced T. penzigi colony size in invaded habitats. Our results reveal the mechanisms underlying the disruption of this mutualism and suggest that P. megacephala invasion may drive long-term declines in tree cover, despite the partial persistence of the ant-acacia symbiosis in invaded areas.

El educador de la salud en la salud pública / The educator for health in public health

RESUMEN Este ensayo expone cómo el educador de la salud, en su quehacer en el campo de la salud pública tradicional, solventa formas de relación con los educandos, enmarcadas en la preponderancia del modelo biomédico, a través de la imposición de significados y valores situados en una concepción biologista de la enfermedad que ha invisibilizado a la salud. En contraste, se presenta la perspectiva crítica de la salud pública alternativa como una posibilidad de resignificar la práctica del educador de la salud. A partir de actuaciones en las que la salud se entiende como un constructo social, el presente artículo busca potenciar abordajes más coherentes con la realidad de los problemas complejos relacionados con la salud desde su conexión con la vida.(AU)

ABSTRACT This essay argues how the health educator in his work in the field of traditional public health solves forms of relationship with the students, framed in the preponderance of the biomedical model, through the imposition of meanings and values located in a conception biologist of the disease that has made health invisible. In contrast, the critical perspective of alternative public health is presented as a possibility to give another meaning to the practice of the health educator. On the roll of the health like a social construct, this paper aims to boost approaches more consistent with the reality of the complex problems related to the health from its connection with the life.(AU)

[The educator for health in public health]. / El educador para la salud en la salud pública.

This essay argues how the health educator in his work in the field of traditional public health solves forms of relationship with the students, framed in the preponderance of the biomedical model, through the imposition of meanings and values located in a conception biologist of the disease that has made health invisible. In contrast, the critical perspective of alternative public health is presented as a possibility to give another meaning to the practice of the health educator. On the roll of the health like a social construct, this paper aims to boost approaches more consistent with the reality of the complex problems related to the health from its connection with the life.

Este ensayo expone cómo el educador de la salud, en su quehacer en el campo de la salud pública tradicional, solventa formas de relación con los educandos, enmarcadas en la preponderancia del modelo biomédico, a través de la imposición de significados y valores situados en una concepción biologista de la enfermedad que ha invisibilizado a la salud. En contraste, se presenta la perspectiva crítica de la salud pública alternativa como una posibilidad de resignificar la práctica del educador de la salud. A partir de actuaciones en las que la salud se entiende como un constructo social, el presente artículo busca potenciar abordajes más coherentes con la realidad de los problemas complejos relacionados con la salud desde su conexión con la vida.

Indicador compuesto en salud: riesgo de transmisión del virus de la rabia / Health composite indicator: risk of transmission of rabies virus

RESUMEN Objetivo Diseñar un indicador compuesto en salud sobre el riesgo de transmisión del virus de la rabia, en el departamento del Meta. Materiales y Métodos Estudio ecológico, exploratorio. Se tomaron los datos de fuentes secundarias procedentes de las bases de datos de la secretaría de salud departamental del Meta e Instituto Colombiano Agropecuario de los años 2009 a 2014. El indicador compuesto en salud, se creó a partir de la normalización (logX) de los datos y selección de las medidas para la elaboración de tres índices temáticos en los 29 municipios del departamento, los cuales fueron integrados mediante la metodología de agregación y cuya distribución se reflejó en un mapeo geográfico con la zonificación del riesgo de transmisión del virus de la rabia a nivel departamental. Resultados En la clasificación del indicador compuesto en salud sobre el riesgo de transmisión de la rabia, el nivel alto corresponde al 34% de los municipios del departamento; en el nivel medio se ubica el 17% y en el nivel bajo el 28%. Los municipios sin riesgo son La Macarena, Mapiripán, Vistahermosa, Villavicencio, Puerto Concordia, Granada y Puerto Rico, representando el 21%. Conclusión El nivel alto del indicador compuesto en salud sobre el riesgo de transmisión del virus de la rabia, se ubica en municipios de la subregión del Río Meta, subregión cordillera y subregión del alto Ariari; caracterizados por altas concentraciones de animales, disminución de la cobertura de vacunación antirrábica y la confirmación circulante del virus.(AU)

ABSTRACT Objective To design a composite health indicator on the risk of rabies virus transmission in the department of Meta, Colombia. Materials and Methods Ecological, exploratory study. Data from secondary sources were collected from the databases of the Meta Department of Health and the Colombian Agricultural Institute (ICA) for the period 2009 - 2014. The composite health indicator was created based on the normalization (logX) of the data and the selection of measures for the elaboration of three thematic indexes in the 29 municipalities of the department. They were integrated by means of the aggregation method, and their distribution was reflected in a geographical mapping with the zoning of the risk for rabies virus transmission in the department. Results In the classification of the composite health indicator on the risk of rabies transmission, the high level corresponds to 34% of the municipalities of the department, the middle level involves 17%, the low level, 28%. The municipalities without risk are La Macarena, Mapiripán, Vistahermosa, Villavicencio, Puerto Concordia, Granada and Puerto Rico, representing 21%. Conclusion The high level of the composite health indicator on the risk of rabies virus transmission is found in municipalities of the Meta River sub-region, the Cordillera sub-region and the upper Ariari sub-region. These areas are characterized by high concentrations of animals, decreased coverage of rabies vaccination and circulating confirmation of the virus.(AU)

[Health composite indicator: risk of transmission of rabies virus]. / Indicador compuesto en salud: riesgo de transmisión del virus de la rabia.

OBJECTIVE: To design a composite health indicator on the risk of rabies virus transmission in the department of Meta, Colombia. MATERIALS AND METHODS: Ecological, exploratory study. Data from secondary sources were collected from the databases of the Meta Department of Health and the Colombian Agricultural Institute (ICA) for the period 2009 - 2014. The composite health indicator was created based on the normalization (logX) of the data and the selection of measures for the elaboration of three thematic indexes in the 29 municipalities of the department. They were integrated by means of the aggregation method, and their distribution was reflected in a geographical mapping with the zoning of the risk for rabies virus transmission in the department. RESULTS: In the classification of the composite health indicator on the risk of rabies transmission, the high level corresponds to 34% of the municipalities of the department, the middle level involves 17%, the low level, 28%. The municipalities without risk are La Macarena, Mapiripán, Vistahermosa, Villavicencio, Puerto Concordia, Granada and Puerto Rico, representing 21%. CONCLUSION: The high level of the composite health indicator on the risk of rabies virus transmission is found in municipalities of the Meta River sub-region, the Cordillera sub-region and the upper Ariari sub-region. These areas are characterized by high concentrations of animals, decreased coverage of rabies vaccination and circulating confirmation of the virus.

OBJETIVO: Diseñar un indicador compuesto en salud sobre el riesgo de transmisión del virus de la rabia, en el departamento del Meta. MATERIALES Y MÉTODOS: Estudio ecológico, exploratorio. Se tomaron los datos de fuentes secundarias procedentes de las bases de datos de la secretaría de salud departamental del Meta e Instituto Colombiano Agropecuario de los años 2009 a 2014. El indicador compuesto en salud, se creó a partir de la normalización (logX) de los datos y selección de las medidas para la elaboración de tres índices temáticos en los 29 municipios del departamento, los cuales fueron integrados mediante la metodología de agregación y cuya distribución se reflejó en un mapeo geográfico con la zonificación del riesgo de transmisión del virus de la rabia a nivel departamental. RESULTADOS: En la clasificación del indicador compuesto en salud sobre el riesgo de transmisión de la rabia, el nivel alto corresponde al 34% de los municipios del departamento; en el nivel medio se ubica el 17% y en el nivel bajo el 28%. Los municipios sin riesgo son La Macarena, Mapiripán, Vistahermosa, Villavicencio, Puerto Concordia, Granada y Puerto Rico, representando el 21%. CONCLUSIÓN: El nivel alto del indicador compuesto en salud sobre el riesgo de transmisión del virus de la rabia, se ubica en municipios de la subregión del Río Meta, subregión cordillera y subregión del alto Ariari; caracterizados por altas concentraciones de animales, disminución de la cobertura de vacunación antirrábica y la confirmación circulante del virus.

Incomplete follow-up of hemoglobinopathy carriers identified by newborn screening despite reporting in electronic medical records.

OBJECTIVE: Has the recent availability of newborn hemoglobinopathy screening results within patient electronic medical records (EMR) of birth hospitals facilitated follow-up by primary care pediatric providers? METHODS: An online survey of all 137 primary care pediatric providers at a New York City academic medical center was conducted in 2008-2009 to assess practices for hemoglobin-apathy trait follow-up. Physicians were resurveyed 1 year later, following educational outreach and a letter of instruction underscoring the availability of screening results in the EMR. All 62 primary care pediatricians were surveyed at a nearby city hospital for comparison. RESULTS: Overall response rate for the initial survey at the teaching hospital was 58% for pediatricians (N = 57) and family physicians (N = 23), and 50% for pediatricians at the city hospital (N = 31). Despite high prevalence of hemoglobinopathies in the population served and screening results in EMRs, only 46.2% of providers surveyed at the academic center reported routinely checking results of their infant patients: 38.6% of pediatricians and 66.7% of family practitioners. Some respondents were unaware that results are available in the EMR. The proportion of providers checking screening results was not significantly affected by educational intervention (N = 40). Provision of recommended follow-up for a positive trait result was modestly improved, especially in referring families for genetic counseling (25% to 50%, p<.01). In contrast, most pediatricians (83%) at the city hospital routinely check and perform follow-up. CONCLUSION: Despite access to results in the EMR and targeted educational outreach, follow-up of hemoglobinopathy screening by primary care varies widely across clinical sites.

Effect of a whey-predominant starter formula containing LCPUFAs and oligosaccharides (FOS/GOS) on gastrointestinal comfort in infants.

Development of new infant formulas aims to replicate the benefits of breast milk. One benefit of breast milk over infant formulas is greater gastrointestinal comfort. We compared indicators of gastrointestinal comfort in infants fed a whey-predominant formula containing long-chain polyunsaturated fatty acids, galacto-oligo-saccharides and fructo-oligosaccharides, and infants fed a control casein-predominant formula without additional ingredients. The single-centre, prospective, double-blind, controlled trial randomly assigned healthy, full-term infants (n=144) to receive exclusively either experimental or control formula from 30 days to 4 months of age. A group of exclusively breast-fed infants served as reference (n=80). At 1, 2, 3, and 4 months, infants' growth parameters were measured and their health assessed. Parents recorded frequency and physical characteristics of infants' stool, frequency of regurgitation, vomiting, crying and colic. At 2-months, gastric emptying (ultrasound) and intestinal transit time (H2 breath test) were measured, and stool samples collected for bacterial analysis. Compared to the control (n=69), fewer of the experimental group (n=67) had hard stools (0.7 vs 7.5%, p<0.001) and more had soft stools (90.8 vs 82.3%, p<0.05). Also compared to the control, the experimental group's stool microbiota composition (mean % bifidobacteria: 78.1 (experimental, n=17), 63.7 (control, n=16), 74.3 (breast-fed, n=20), gastric transit times (59.6 (experimental, n=53), 61.4 (control, n=62), 55.9 (breast-fed, n=67) minutes) and intestinal transit times (data not shown) were closer to that of the breast-fed group. Growth parameter values were similar for all groups. The data suggest that, in infants, the prebiotic-containing whey-based formula provides superior gastrointestinal comfort than a control formula.

Association between anemia and aflatoxin B1 biomarker levels among pregnant women in Kumasi, Ghana.

Aflatoxins are fungal metabolites that contaminate staple food crops in many developing countries. Up to 40% of women attending a prenatal clinic in Africa may be anemic. In a cross-sectional study of 755 pregnant women, Aflatoxin B(1)-lysine adducts (AF-ALB) levels were determined by high-performance liquid chromatography. Participants were divided into quartiles "low," "moderate," "high," and "very high." Anemia was defined as hemoglobin levels < 11 g/dL. Logistic regression was used to examine the association of anemia with AF-ALB. The mean AF-ALB level was 10.9 pg/mg (range = 0.44-268.73 pg/mg); 30.3% of participants were anemic. The odds of being anemic increased 21% (odds ratio [OR], 1.21, P = 0.01) with each quartile of AF-ALB reaching an 85% increased odds in the "very high" compared with the "low" category (OR, 1.85; confidence interval [CI], 1.16-2.95). This association was stronger among women with malaria and findings were robust when women with evidence of iron deficiency anemia were excluded. This study found a strong, consistent association between anemia in pregnancy and aflatoxins.

Malaria, intestinal helminths and other risk factors for stillbirth in Ghana.

OBJECTIVE: The objective of the study was to assess Plasmodium/intestinal helminth infection in pregnancy and other risk factors for stillbirth in Ghana. METHODS: A cross-sectional study of women presenting for delivery in two hospitals was conducted during November-December 2006. Data collected included sociodemographic information, medical and obstetric histories, and anthropometric measures. Laboratory investigations for the presence of Plasmodium falciparum and intestinal helminths, and tests for hemoglobin levels were also performed. RESULTS: The stillbirth rate was relatively high in this population (5%). Most of the stillbirths were fresh and 24% were macerated. When compared to women with no malaria, women with malaria had increased risk of stillbirth (OR = 1.9, 95% CI = 1.2-9.3). Other factors associated with stillbirth were severe anemia, low serum folate concentration, past induced abortion, and history of stillbirth. CONCLUSION: The fact that most of the stillbirths were fresh suggests that higher quality intrapartum care could reduce stillbirth rates.

The effect of malaria and intestinal helminth coinfection on birth outcomes in Kumasi, Ghana.

This study was conducted to investigate the effect of Plasmodium falciparum and intestinal helminth coinfection on maternal anemia and birth outcomes. A cross-sectional study of 746 women who delivered in two hospitals in Kumasi was conducted. Data were collected using an investigator-administered questionnaire and from patients' medical records. Blood was collected for determination of P. falciparum and hemoglobin levels. Adverse pregnancy outcomes were high (44.6%). Coinfection (versus no infection) was associated with 3-fold increase in low birth weight. For women with anemia, coinfection was 2.6 times and 3.5 times as likely to result in preterm deliveries and small for gestational age infants. The odds of having anemia was increased almost 3-fold by coinfection. Coinfection (versus helminth only) resulted in increased risks of anemia, low birth weight, and small for gestational age infants. This study demonstrates that women with malaria and intestinal helminth coinfection are at particular risk of adverse birth outcomes.

Malaria and intestinal helminth co-infection among pregnant women in Ghana: prevalence and risk factors.

Both malaria and intestinal helminths are endemic in sub-Saharan Africa, and their co-infection occurs commonly. This cross-sectional study assessed the prevalence of malaria and intestinal helminth co-infection in a sample of > 700 pregnant women in Ghana and identified risk factors for co-infection. The prevalence of malaria infection, intestinal helminth infection(s), and co-infection was 36.3%, 25.7%, and 16.6%, respectively. Women with intestinal helminth infection(s) were 4.8 times more likely to have malaria infection. Young age, low income, being single, and being primigravid were each associated with increased odds of co-infection. These associations were present when assessed separately for primi- and multigravid women, but the strength of associations varied considerably for the two groups of women. Young age had the strongest association among both primigravid (odds ratio = 5.2) and multigravid (odds ratio = 3.2) women. This study shows relatively high prevalence rates of malaria, intestinal helminths, and co-infection in pregnant women in Ghana.

A specific role for AKT3 in the genesis of ovarian cancer through modulation of G(2)-M phase transition.

Ovarian cancer is the major cause of death from gynecological malignancy, and there is an urgent need for new therapeutic targets. The phosphatidylinositol 3-kinase (PI3K)/AKT pathway has been strongly implicated in the genesis of ovarian cancer. However, to identify and evaluate potential targets for therapeutic intervention, it is critical to understand the mechanism by which the PI3K/AKT pathway facilitates ovarian carcinogenesis. Here, we show that AKT3 is highly expressed in 19 of 92 primary ovarian tumors. Strikingly, purified AKT3 exhibited up to 10-fold higher specific activity than AKT1, potentially amplifying the effects of AKT3 overexpression. Consistent with this finding, AKT3 levels in a range of ovarian cancer cell lines correlated with total AKT activity and proliferation rates, implicating AKT3 as a key mediator of ovarian oncogenesis. Specific silencing of AKT3 using short hairpin RNA markedly inhibited proliferation of the two cell lines with highest AKT3 expression and total AKT activity, OVCA429 and DOV13, by slowing G(2)-M phase transition. These findings are consistent with AKT3 playing a key role in the genesis of at least one subset of ovarian cancers.

Fungi in bottled water: a case study of a production plant

A one-year fungal survey of a water bottling plant was conducted in order to evaluate the incidence and fluctuations of the mycobiota. The dominant fungal genera in order of highest numbers isolated were Penicillium, Cladosporium and Trichoderma followed by Aspergillus, Paecilomyces, and others. As expected, the highest number of isolates were collected during the warmer months, particularly May and June. Indeed during these two months there were more fungi present in the water, indicating that during those times of the year when fungal contamination is high, 0.4 mm filters should be changed on a more regular basis. In order to assess whether contamination was single or multi-loci, molecular methods based on the PCR were used for Penicillium brevicompactum. Overall, fungal contamination arose from multiple sources. Some P. brevicompactum strains were very "alike" and were detected during different sampling times, indicating that they were endemic to the plant. There was no evidence to suggest that fungi detected in the source water passed through to other parts of the plant. However, there was evidence that fungal strains isolated from the water filter were detected elsewhere in the factory, confirming the need to change filters more regularly during periods of high fungal contamination. In order to improve quality control a HACCP programme was implemented and Best Practice Guidelines introduced(AU)