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Wolbachia-based biocontrol has recently emerged as a potential method for prevention and control of dengue and other vector-borne diseases. Major vector species, such as Aedes aegypti females, when deliberately infected with Wolbachia become less capable of getting viral infections and transmitting the virus to human hosts. In this paper, we propose an explicit sex-structured population model that describes an interaction of uninfected (wild) male and female mosquitoes and those deliberately infected with wMelPop strain of Wolbachia in the same locality. This particular strain of Wolbachia is regarded as the best blocker of dengue and other arboviral infections. However, wMelPop strain of Wolbachia also causes the loss of individual fitness in Aedes aegypti mosquitoes. Our model allows for natural introduction of the decision (or control) variable, and we apply the optimal control approach to simulate wMelPop Wolbachia infestation of wild Aedes aegypti populations. The control action consists in continuous periodic releases of mosquitoes previously infected with wMelPop strain of Wolbachia in laboratory conditions. The ultimate purpose of control is to find a tradeoff between reaching the population replacement in minimum time and with minimum cost of the control effort. This approach also allows us to estimate the number of Wolbachia-carrying mosquitoes to be released in day-by-day control action. The proposed method of biological control is safe to human health, does not contaminate the environment, does not make harm to non-target species, and preserves their interaction with mosquitoes in the ecosystem.

Introduction: Tropical Andean and Amazonian ecosystems shape the great biodiversity found in Peru. However, studies on mosquitoes (Diptera: Culicidae) in the country are scarce, resulting in an information gap regarding their diversity, ecology, distribution, and abundance. Objective: To search for documented evidence on the diversity and distribution of mosquitoes (Diptera: Culicidae) in Peru, and to establish —in relation to species of medical relevance— their potential link with the epidemiological cycle of some metaxenic diseases. Materials and methods: A literature review was conducted in Google Scholar, ScienceDirect, PubMed, and SciELO, as well as in 7 databases specialized in insect taxonomy, using specific terms and their combinations by means of Boolean operators (“AND” and “OR”). Search strategy: study types: original research articles, review articles, books, and book chapters; publication period: no initial date - June 2020; languages: English, Spanish, and Portuguese. Results: A total of 99 studies were retrieved after the initial search, 84 in the 4 electronic databases and 15 in the specialized databases, of which 41 met the inclusion criteria. One additional record was included due to its relevance to the objective of the review. The studies included were original articles (n=28), review articles (n=6), books (n=5), book chapters (n=2), and undergraduate theses (n=1). Regarding the language of publication, 25 (59.52%) were published in English and 17 (40.48%) in Spanish. Conclusions. In Peru, the greatest diversity of mosquito genera is found in the departments of Loreto, Huánuco, and Madre de Dios. Knowledge of the diversity of mosquitoes in Peru that have the potential to cause health issues is relatively scarce and is focused on Aedes aegypti and some species of the Anopheles and Culex genera, thus overlooking a rich diversity distributed in the Amazonian forests, high jungle, and inter-Andean valleys. Introducción. Los ecosistemas tropicales andinos y amazónicos determinan la gran biodiversidad presente en Perú. Sin embargo, los estudios sobre mosquitos (Diptera: Culicidae) en el país son escasos, lo que resulta en un vacío de información en cuanto a su diversidad, ecología, distribución y abundancia. Objetivos. Buscar evidencia documentada sobre la diversidad y la distribución de mosquitos en el Perú, y establecer —con relación a las especies de importancia médica— su potencial vínculo con el ciclo epidemiológico de algunas enfermedades metaxénicas. Materiales y métodos. Se realizó una revisión de la literatura en Google Académico, ScienceDirect, PubMed y Scielo, así como en siete bases de datos especializadas en taxonomía de insectos, usando términos específicos y diferentes combinaciones con operadores booleanos (“AND” y “OR”). Estrategia de búsqueda: tipos de estudios: artículos originales de investigación, artículos de revisión, libros y capítulos de libros; periodo de publicación: sin límite inicial a junio del 2020; idiomas: inglés, español y portugués. Resultados. La búsqueda inicial arrojó 99 estudios, 84 en las 4 bases de datos electrónicas y 15 en las bases de datos especializadas, de los cuales 41 cumplieron los criterios de inclusión. También se incluyó un registro adicional debido a su relevancia con el objetivo de la revisión. Los estudios incluidos fueron artículos originales (n=28), artículos de revisión (n=6), libros (n=5), capítulos de libro (n=2) y tesis de pregrado (n=1). Respecto al idioma de publicación, 25 (59.52%) estaban en inglés y 17 (40.48%), en español. Conclusiones. En Perú, la mayor diversidad de géneros de mosquitos se encuentra presente en los departamentos de Loreto, Huánuco y Madre de Dios. El conocimiento sobre la diversidad de mosquitos en Perú que tienen el potencial de generar problemas de salud es relativamente escaso y se centra en el Aedes aegypti y algunas especies de los géneros Anopheles y Culex, dejando de lado una rica diversidad distribuida en los bosques amazónicos, la selva alta y los valles interandinos.

En proyectos hidroeléctricos se han realizado pocas investigaciones para determinar la composición taxonómica de dípteros de la familia Psychodidae, subfamilia Phlebotominae. En este trabajo se realizó un inventario taxonómico de flebótomos en el área de influencia de la central hidroeléctrica de Ituango, departamento de Antioquia con el fin de actualizar su distribución y resaltar su importancia médica como vectores del protozoo del género Leishmania. Para esto, se realizaron monitoreos entomológicos con trampas CDC y trampas Shannon, en diez municipios de la subregión occidente (Santa Fe de Antioquia, Peque, Olaya, Liborina y Sabanalarga) y de la subregión norte (municipios de Ituango, Briceño, Valdivia, Toledo y San Andrés de Cuerquia). Para la identificación taxonómica se utilizaron las claves de Young y Duncan y Galati. En total se recolectaron 7993 flebótomos, distribuidos en 39 especies según Galati, destacándose seis especies consideradas vectores de especies de Leishmania, que causan la leishmaniasis cutánea. Estas especies fueron Lutzomyia (Trl.) gomezi, Lu. (Hel.) hartmanni, Psychodopygus panamensis, Pintomyia (Pif.) columbiana, Nyssomyia. trapidoi y Ny. yuilli yuilli. Los datos indican que la zona de muestreo es endémica para la leishmaniasis debido a la presencia de vectores transmisores de este parásito. El inventario sobre la distribución de flebótomos servirá de base para estudios posteriores que permitan la implementación de estrategias de vigilancia y control.

Smart cities work with large volumes of data from sensor networks and other sources. To prevent data from being compromised by attacks or errors, smart city IT administrators need to apply attack detection techniques to evaluate possible incidents as quickly as possible. Machine learning has proven to be effective in many fields and, in the context of wireless sensor networks (WSNs), it has proven adequate to detect attacks. However, a smart city poses a much more complex scenario than a WSN, and it has to be evaluated whether these techniques are equally valid and effective. In this work, we evaluate two machine learning algorithms (support vector machines (SVM) and isolation forests) to detect anomalies in a laboratory that reproduces a real smart city use case with heterogeneous devices, algorithms, protocols, and network configurations. The experience has allowed us to show that, although these techniques are of great value for smart cities, additional considerations must be taken into account to effectively detect attacks. Thus, through this empiric analysis, we point out broader challenges and difficulties of using machine learning in this context, both for the technical complexity of the systems, and for the technical difficulty of configuring and implementing them in such environments.

Production and exportation of berries in Mexico has increased over the last decade, expanding the land area dedicated to the cultivation of these fruits, and increasing their associated pests. Recently, the proliferation of a group of flies belonging to the Sciaridae (Diptera) has become a problem for berry farming. Adults can be mechanical vectors of several species of plant pathogenic fungi. Larvae can cause indirect damage by feeding at the base of leaves, stems and roots, increasing plant susceptibility to pathogens. The aim of the present research was to identify fungus gnat species associated with berry varieties from 18 production areas in the states of Baja California, Michoacán, Jalisco, Puebla, and Tlaxcala. Sampling was carried out under multi-span polytunnels from 2018 to 2020. A total of 31 samples with 317 specimens were processed and identified using morphological characters. Four species were identified: Pseudosciara forceps (Pettey), Pseudosciara neotropica (Lane), Lycoriella sativae (Johannsen), and Bradysia impatiens (Johannsen). All species except for B. impatiens are first reports for Mexico but B. impatiens was the most frequently encountered and widely distributed. La producción y exportación de berries en México se incrementó durante la última década, lo cual amplió la superficie dedicada al cultivo de las frutillas, y por consiguiente sus plagas asociadas. Recientemente la proliferación de un grupo de moscas pertenecientes a la familia Sciaridae (Diptera) se ha convertido en un problema para la producción de berries. Debido a sus hábitos, los adultos pueden ser vectores mecánicos de varias especies de hongos patógenos de plantas, dependiendo de la especie cultivada, parece ser que las larvas causan daño indirecto derivado de su actividad alimenticia en la base de las hojas, tallos y raíces, lo cual resulta en plantas susceptibles a patógenos por la presencia de conidios de hongos en el sustrato o los que puedan ser trasportados por las mismas larvas y adultos. Derivado de este problema, el objetivo del presente trabajo fue identificar las especies de moscas de los hongos asociadas con el cultivo de berries en 18 áreas de producción distribuidas en los estados de Baja California, Michoacán, Jalisco, Puebla y Tlaxcala. El muestreo se realizó bajo condiciones de macrotúnel en los años 2018 y 2020 debido a las épocas de producción en cada sitio. Un total de 31 muestras con 317 ejemplares se procesaron e identificaron usando características morfológicas. Se identificaron cuatro especies: Pseudosciara forceps (Pettey), Pseudosciara neotropica (Lane), Lycoriella sativae (Johannsen), y Bradysia impatiens (Johannsen). Todas las especies excepto B. impatiens representan nuevo reporte para México sin embargo la última especie fue la más ampliamente distribuida, siendo la más frecuente en los sitios de muestreo, también las cuatro especies se registran para este grupo de cultivos en este país.

Introductions of non-native predators often reduce biodiversity and affect natural predator–prey relationships and may increase the abundance of potential disease vectors (e.g., mosquitoes) indirectly through competition or predation cascades. The Santa Monica Mountains (California, U.S.A.), situated in a global biodiversity hotspot, is an area of conservation concern due to climate change, urbanization, and the introduction of non-native species. We examined the effect of non-native crayfish (Procambarus clarkii) on an existing native predator, dragonfly nymphs (Aeshna sp.), and their mosquito larvae (Anopheles sp.) prey. We used laboratory experiments to compare the predation efficiency of both predators, separately and together, and field data on counts of dragonfly nymphs and mosquito larvae sampled from 13 local streams. We predicted a lower predation efficiency of crayfish compared with native dragonfly nymphs and a reduced predation efficiency of dragonfly nymphs in the presence of crayfish. Dragonfly nymphs were an order of magnitude more efficient predators than crayfish, and dragonfly nymph predation efficiency was reduced in the presence of crayfish. Field count data showed that populations of dragonfly nymphs and mosquito larvae were strongly correlated with crayfish presence in streams, such that sites with crayfish tended to have fewer dragonfly nymphs and more mosquito larvae. Under natural conditions, it is likely that crayfish reduce the abundance of dragonfly nymphs and their predation efficiency and thereby, directly and indirectly, lead to higher mosquito populations and a loss of ecosystem services related to disease vector control. La introducción de depredadores no nativos con frecuencia reduce la biodiversidad y afecta a las relaciones naturales entre presa y depredador, e incluso puede incrementar indirectamente la abundancia de vectores potenciales de enfermedades (p.ej.: mosquitos) por medio de la competencia o las cascadas de depredación. Las montañas de Santa Mónica (California, E.U.A.), situadas en un punto caliente de biodiversidad global, son un área de importancia para la conservación debido al cambio climático, la urbanización y la introducción de especies no nativas. Examinamos el efecto que tiene un cangrejo de río no nativo (Procambarus clarkii) sobre un depredador en existencia, las ninfas de libélula (Aeshna sp.), y sobre su presa: las larvas de mosquito (Anopheles sp.). Usamos experimentos de laboratorio para comparar la eficiencia de depredación de ambos depredadores, de manera separada y conjunta, y datos de campo sobre los conteos de ninfas de libélula y larvas de mosquito muestreadas en 13 riachuelos locales. Predijimos una eficiencia de depredación más baja de los cangrejos de río en comparación con las ninfas de libélula y una eficiencia de depredación reducida delas ninfasdelibélula en presencia de los cangrejos de río. Lasninfasde libélula fueron depredadores un orden de magnitud más eficientes que los cangrejos de río, y la eficiencia de depredación de las ninfas de libélula estuvo reducida en la presencia de cangrejos de río. Los datos de conteo de campo mostraron que las poblaciones de ninfas de libélula y de larvas de mosquito tuvieron una fuerte correlación con la presencia de cangrejos de río en los riachuelos, de tal manera que los sitios con cangrejos de río tendieron a tener menos ninfas de libélula y más larvas de mosquito. Bajo condiciones naturales, es probable que los cangrejos de río reduzcan la abundancia de ninfas de libélula y su eficiencia de depredación, lo que resulta directa e indirectamente en poblaciones mayores de mosquitos y una pérdida de los servicios ambientales relacionados con el control de los vectores de enfermedades. 引入外来捕食者常常会导致生物多样性丧失，影响自然界捕食者-猎物关系，还可能通过竞争或营养级联 效应间接增加潜、在疾病传播媒介_ 蚊子) 的数量。圣莫尼卡山脉(美国加利福尼亚州) 位于全球生物多样性热 点地区，因气候变化、城市化和外来物种的引入受到了保护关注。我们在这里分析了外来的小龙虾（克氏原螯 奸Procambarus clarkii) 对原有本地捕食者蜻艇若虫 (Aeshna sp.) 及其猎物蚊子幼虫 (Anopheles sp.) 的影晌。 我们通过实验室实验比较了这两种捕食者分别捕食和一起捕食的效率，以及当地13 条溪流中蜻蜓若虫和蚊子 幼虫的数量。我们预测小龙虾的捕食效率低于本地的蜻蜓若虫，而在有小龙虾存在的情况下，蜻艇若虫的捕食效 率会下降。结果表明蜻蜓若虫的捕食效率比小龙虾高一个数量级，且小龙虾存在时蜻蜓若虫的捕食效率的确会 下降。野外统计的数据显示，蜻蜓若虫和蚊子幼虫的种群数量与溪流中小龙虾的存在有很强的相关性有小龙虾 的位点一般蜻蜓若虫较少、蚊子幼虫较多。在自然条件下，小龙虾可能会引起蜻蜓若虫丰度下降，捕食效率降 低，从而直接和间接地导致蚊子种群数量增加，还导致与控制疾病传播媒介相关的生态系统服务功能丧失

La malaria es un grave problema de salud pública en Colombia, con Plasmodium falciparum y P. vivax como los parásitos responsables del 97% de los casos. En el año 2019 el departamento de Antioquia presentó 7076 casos de malaria, siendo el municipio de Turbo uno de los más afectados. El objetivo de esta investigación fue determinar las especies de Anopheles spp. presentes en áreas endémicas de transmisión de malaria en Turbo, Antioquia, y evaluar su infección natural con Plasmodium spp. Se realizaron cuatro muestreos entre 2015 y 2016; los mosquitos fueron recolectados en el intradomicilio, peridomicilio y animales de corral; además, se realizó búsqueda activa de especímenes inmaduros en criaderos naturales. Se recolectaron 121 mosquitos adultos, pertenecientes a cuatro especies, An. albimanus (n=117), An. triannulatus s.l. (n=1), An, apicimacula s.l. (n=1) y An. pseudopunctipennis s.l. (n=2). Igualmente, se recolectaron 65 larvas pertenecientes a tres especies, An. albimanus (n=58), An. triannulatus (n=1) y An. apicimacula (n=6). Ninguno de los especímenes recolectados fue encontrado infectado con Plasmodium. Anopheles albimanus podría ser el principal vector de malaria en las localidades estudiadas. Posiblemente, An. pseudopunctipennis s.l. puede jugar un papel en la transmisión de malaria en presencia de personas infectadas y con altas densidades. Las bajas densidades de mosquitos encontradas en este estudio indican que las estrategias de control desarrolladas en los años 2014-2015, por las instituciones de salud locales, con Bacillus sphaericus e insecticidas están resultando eficaces.

With globalization, agriculture and aquaculture activities are increasingly affected by diseases that are spread through movement of crops and stock. Such movements are also associated with the introduction of non‐native species via hitchhiking individual organisms. The oyster industry, one of the most important forms of marine aquaculture, embodies these issues. In Europe disease outbreaks affecting cultivated populations of the naturalized oyster Crassostrea gigas caused a major disruption of production in the late 1960s and early 1970s. Mitigation procedures involved massive imports of stock from the species’ native range in the northwestern Pacific from 1971 to 1977. We assessed the role stock imports played in the introduction of non‐native marine species (including pathogens) from the northwestern Pacific to Europe through a methodological and critical appraisal of record data. The discovery rate of non‐native species (a proxy for the introduction rate) from 1966 to 2012 suggests a continuous vector activity over the entire period. Disease outbreaks that have been affecting oyster production since 2008 may be a result of imports from the northwestern Pacific, and such imports are again being considered as an answer to the crisis. Although successful as a remedy in the short and medium terms, such translocations may bring new diseases that may trigger yet more imports (self‐reinforcing or positive feedback loop) and lead to the introduction of more hitchhikers. Although there is a legal framework to prevent or reduce these introductions, existing procedures should be improved.

The tensorial nature of a quantity permits us to formulate transformation rules for its components under a change of basis. These rules are relatively simple and easily grasped by any engineering student familiar with matrix operators in linear algebra. More complex problems arise when one considers the tensor fields that describe continuum bodies. In this case general curvilinear coordinates become necessary. The principal basis of a curvilinear system is constructed as a set of vectors tangent to the coordinate lines. Another basis, called the dual basis, is also constructed in a special manner. The existence of these two bases is responsible for the mysterious covariant and contravariant terminology encountered in tensor discussions.

A detailed account is given of the history, aetiology, biology, epidemiology, detection, geographical distribution, and control of huanglongbing (HLB), a destructive disease of citrus that represents a major threat to the world citrus industry, and is slowly invading new citrusgrowing areas. HLB, whose name in Chinese means \"yellow dragon disease\", was first reported from southern China in 1919 and is now known to occur in next to 40 different Asian, African, Oceanian, South and North American countries. The agent is a phloem-restricted, non cultured, Gram-negative bacterium causing crippling diseases denoted \"greening\" in South Africa, \"mottle leaf\" in the Philippines, \"dieback\" in India, \"vein phloem degeneration\" in Indonesia. The HLB bacterium belongs to the genus Candidatus Liberibacter, three species of which are currently known, Candidatus Liberibacter asiaticus, occurring in Asian countries and, to a lesser extent, in Brazil and the USA (Florida), Candidatus Liberibacter africanus with its subspecies \"capensis\", recorded from African countries, and Candidatus Liberibacter americanus present in Brazil. The suggestion is that each liberibacter species has evolved in the continent after which it is named. HLB symptoms are virtually the same wherever the disease occurs. Infected trees show a blotchy mottle condition of the leaves that results in the development of yellow shoots, the early and very characteristic symptom of the disease. Trees are stunted, declining and bear a few, small-sized, and deformed (lop-sided) fruits, that are poorly coloured (greening) and with coloration starting at the peduncular end (colour inversion). HLB can be transmitted by grafting from citrus to citrus and by dodder to periwinkle. The psyllids Trioza erytreae and Diaphorina citri are natural vectors. Two different types of HLB are known: the heat-sensitive African form transmitted by T. erytreae, which develops at temperatures of 22-25°C, and the heat-tolerant Asian form, transmitted by D. citri, which stands temperatures well above 30°C. Although the HLB pathogen can be identified by electron microscopy, other laboratory methods are used for routine detection. ELISA with monoclonal antibodies is not recommended. Better systems are dot blot hybridization with a DNA probe, and various PCR formats (one-step, nested, multiplex) using species-specific primers based on 16S rRNA or rplKAJL-rpoBC operon sequences. Because no curative methods of HLB are available, control is preventive and largely based on inoculum elimination by removal of infected trees and chemical treatments against vectors. Strict quarantine measures must be implemented to impair further international spread of HLB agents and their vectors.