Synthetic growth by self-lubricated photopolymerization and extrusion inspired by plants and fungi.

Many natural organisms, such as fungal hyphae and plant roots, grow at their tips, enabling the generation of complex bodies composed of natural materials as well as dexterous movement and exploration. Tip growth presents an exemplary process by which materials synthesis and actuation are coupled, providing a blueprint for how growth could be realized in a synthetic system. Herein, we identify three underlying principles essential to tip-based growth of biological organisms: a fluid pressure driving force, localized polymerization for generating structure, and fluid-mediated transport of constituent materials. In this work, these evolved features inspire a synthetic materials growth process called extrusion by self-lubricated interface photopolymerization (E-SLIP), which can continuously fabricate solid profiled polymer parts with tunable mechanical properties from liquid precursors. To demonstrate the utility of E-SLIP, we create a tip-growing soft robot, outline its fundamental governing principles, and highlight its capabilities for growth at speeds up to 12 cm/min and lengths up to 1.5 m. This growing soft robot is capable of executing a range of tasks, including exploration, burrowing, and traversing tortuous paths, which highlight the potential for synthetic growth as a platform for on-demand manufacturing of infrastructure, exploration, and sensing in a variety of environments.

Integrated Surveillance System for Controlling COVID-19 on a University Campus, 2020‒2021.

To minimize the impacts of COVID-19 and to keep campus open, Cornell University's Ithaca, NY, campus implemented a comprehensive process to monitor COVID-19 spread, support prevention practices, and assess early warning indicators linked to knowledge, behaviors, and attitudes of campus community members. The integrated surveillance approach informed leadership and allowed for prompt adjustments to university policies and practices through evidence-based decisions. This approach enhanced healthy behaviors and promoted the well-being and safety of all community members. (Am J Public Health. 2022;112(7):980-984. https://doi.org/10.2105/AJPH.2022.306838).

The colloidal nature of complex fluids enhances bacterial motility.

The natural habitats of microorganisms in the human microbiome, ocean and soil ecosystems are full of colloids and macromolecules. Such environments exhibit non-Newtonian flow properties, drastically affecting the locomotion of microorganisms1-5. Although the low-Reynolds-number hydrodynamics of swimming flagellated bacteria in simple Newtonian fluids has been well developed6-9, our understanding of bacterial motility in complex non-Newtonian fluids is less mature10,11. Even after six decades of research, fundamental questions about the nature and origin of bacterial motility enhancement in polymer solutions are still under debate12-23. Here we show that flagellated bacteria in dilute colloidal suspensions display quantitatively similar motile behaviours to those in dilute polymer solutions, in particular a universal particle-size-dependent motility enhancement up to 80% accompanied by a strong suppression of bacterial wobbling18,24. By virtue of the hard-sphere nature of colloids, whose size and volume fraction we vary across experiments, our results shed light on the long-standing controversy over bacterial motility enhancement in complex fluids and suggest that polymer dynamics may not be essential for capturing the phenomenon12-23. A physical model that incorporates the colloidal nature of complex fluids quantitatively explains bacterial wobbling dynamics and mobility enhancement in both colloidal and polymeric fluids. Our findings contribute to the understanding of motile behaviours of bacteria in complex fluids, which are relevant for a wide range of microbiological processes25 and for engineering bacterial swimming in complex environments26,27.

Band Gap Tuning of Films of Undoped ZnO Nanocrystals by Removal of Surface Groups.

Transparent conductive oxides (TCOs) are widely used in optoelectronic devices such as flat-panel displays and solar cells. A significant optical property of TCOs is their band gap, which determines the spectral range of the transparency of the material. In this study, a tunable band gap range from 3.35 eV to 3.53 eV is achieved for zinc oxide (ZnO) nanocrystals (NCs) films synthesized by nonthermal plasmas through the removal of surface groups using atomic layer deposition (ALD) coating of Al2O3 and intense pulsed light (IPL) photo-doping. The Al2O3 coating is found to be necessary for band gap tuning, as it protects ZnO NCs from interactions with the ambient and prevents the formation of electron traps. With respect to the solar spectrum, the 0.18 eV band gap shift would allow ~4.1% more photons to pass through the transparent layer, for instance, into a CH3NH3PbX3 solar cell beneath. The mechanism of band gap tuning via photo-doping appears to be related to a combination of the Burstein-Moss (BM) and band gap renormalization (BGN) effects due to the significant number of electrons released from trap states after the removal of hydroxyl groups. The BM effect shifts the conduction band edge and enlarges the band gap, while the BGN effect narrows the band gap.

Confounding influences of malnutrition and Plasmodium falciparum and Schistosoma haematobium infections on haematological parameters in school children in Muyuka, Cameroon.

BACKGROUND: School-aged children (SAC) are a high-risk demographic group for infectious diseases and malnutrition. The objective of this study was to assess the burden and the effect of Plasmodium falciparum and Schistosoma haematobium infections on the haematological indices in SAC and the confounding influence of malnutrition on the outcomes. METHODS: This cross-sectional study was conducted in SAC 4-14 years old living in Ikata, Bafia and Mile 14-Likoko in Muyuka, Cameroon. Anthropometric measures of malnutrition were obtained and blood samples collected were used for detection of malaria parasites by Giemsa-stained blood films using light microscopy and complete blood count analysis using an automated haematology analyser. Urine samples collected were used to detect micro haematuria with the aid of reagent strips and the eggs of S. haematobium by urine filtration technique. Multiple linear regression model was used to examine influence of independent variables on haematological parameters. RESULTS: Out of the 606 SAC examined, the prevalence of single infections with Plasmodium or S. haematobium and co-infection with both parasites was 16.2, 16.3 and 8.3%, respectively. Overall, malaria parasite (MP), urogenital schistosomiasis, malnutrition, anaemia, haematuria, microcytosis and thrombocytopenia was prevalent in 24.4, 24.6, 25.9, 74.4, 12.2, 45.4 and 11.1% of SAC, respectively. A significant linear decline (P = 0.023) in prevalence of P. falciparum infection with the severity of stunting was observed. Factors that significantly influenced haematological parameters included haemoglobin: age, stunting and MP; haematocrit: age and MP; white blood cell count: age; red blood cell count; age and MP; lymphocyte counts: stunting; mean cell volume: age; mean cell haemoglobin: age and stunting; mean cell haemoglobin concentration: sex, stunting and red cell distribution width-coefficient of variation: sex, age and stunting. CONCLUSIONS: Malnutrition, Plasmodium and S. haematobium infections are common while anaemia is a severe public health problem in Muyuka, Cameroon. The interaction between haematological parameters with malaria parasites as well as linear growth index was negative and other interactions indicate systemic inflammation. While findings provide contextual intervention targets to ensure the judicious use of the limited resources, there is need for regular monitoring and proper treatment to improve the health of the underserved population.

Epidemiology of human leptospirosis in Saint Lucia, 2010–2017

[ABSTRACT]. Objective. To describe the epidemiology of human leptospirosis cases in Saint Lucia from 2010 to 2017 and determine whether there was a relationship between cases and rainfall and temperature. Methods. A retrospective analytical study was undertaken to describe the seasonal patterns of human leptospirosis cases reported to the Ministry of Health of Saint Lucia between 2010 and 2017. Confirmed cases of leptospirosis were analyzed according to age, sex, seasonality, and geographical distribution. Disease incidence was calculated and the association of cases with geographical distribution, rainfall, and temperature was investigated. Results. A total of 353 leptospirosis cases were reported between 2010 and 2017 and of these, 145 (40.6%) were laboratory confirmed. Cases were aged 7 to 73 years (mean 34 years; median 30 years) with a male to female ratio of 4.2:1. Six deaths were reported during the period, with an overall case fatality rate of 4.1%. There was no relationship between location (district) and incidence of leptospirosis in Saint Lucia. There was a weak correlation between rainfall and leptospirosis cases during the 8-year period (rs = 0.25, p = 0.015) but the correlation between cases and seasons was not statistically significant (dry season rs = 0.13, p = 0.42; wet season rs = 0.23, p = 0.08). There was no correlation between leptospirosis cases and temperature (rs = 0.07, p = 0.49). Conclusions. Leptospirosis has a seasonal distribution in Saint Lucia, with outbreaks during periods following increased rainfall and flooding, such as in the aftermath of tropical storms and hurricanes. Saint Lucia and other Caribbean countries should enhance surveillance for leptospirosis given the likelihood of increased flooding following frequent and intense rainfall due to climate change.

[RESUMEN]. Objetivo. Describir las características epidemiológicas de los casos de leptospirosis humana en Santa Lucía entre el año 2010 y el año 2017, y determinar si hubo un vínculo entre el número de casos, las precipitaciones y la temperatura. Métodos. Se llevó a cabo un estudio analítico retrospectivo para describir el patrón estacional de los casos de leptospirosis humana notificados al Ministerio de Salud de Santa Lucía entre el año 2010 y el año 2017. Los casos confirmados de leptospirosis se analizaron según la edad, el sexo, el carácter estacional y la distribución geográfica. Se calculó la incidencia de la enfermedad y se evaluó la relación entre el número de casos y la distribución geográfica, las precipitaciones y la temperatura. Resultados. Se notificaron 353 casos de leptospirosis entre el 2010 y el 2017, entre ellos, 145 (40,6%) casos confirmados mediante pruebas de laboratorio. Los casos se presentaron en personas de 7 a 73 años (media de 34 años; mediana de 30 años) con una razón hombre:mujer de 4,2:1. Se notificaron 6 muertes durante el mismo período y una tasa de letalidad general de 4,1%. No se encontró un vínculo entre la ubicación (distrito) y la incidencia de la leptospirosis en Santa Lucía. Se estableció una correlación débil entre las precipitaciones y el número de casos de leptospirosis durante el período de 8 años (rs = 0,25, p = 0,015); la correlación entre el número de casos y las estaciones no fue estadísticamente significativa (estación seca, rs = 0,13, p = 0,42; estación húmeda, rs = 0,23, p = 0,08). No se estableció una correlación entre el número de casos de leptospirosis y la temperatura (rs = 0,07, p = 0,49). Conclusiones. La leptospirosis presenta una distribución estacional en Santa Lucía, con brotes que surgen tras períodos de aumento de las precipitaciones e inundaciones; por ejemplo, después de tormentas y huracanes tropicales. Santa Lucía y otros países del Caribe deben mejorar la vigilancia de la leptospirosis dado que el cambio climático aumenta la probabilidad de inundaciones tras períodos de precipitaciones frecuentes e intensas.

[RESUMO]. Objetivo. Descrever a epidemiologia dos casos de leptospirose humana em Santa Lúcia de 2010 a 2017 e determinar se houve uma relação entre a ocorrência de casos e precipitação e temperatura. Métodos. Um estudo retrospectivo analítico foi realizado para descrever o padrão sazonal dos casos de leptospirose humana notificados ao Ministério da Saúde de Santa Lúcia entre 2010 e 2017. Os casos confirmados de leptospirose foram analisados por idade, sexo, sazonalidade e distribuição geográfica. A incidência da doença foi calculada e a associação entre a ocorrência de leptospirose e distribuição geográfica dos casos, precipitação e temperatura foi pesquisada. Resultados. Ao todo, 353 casos de leptospirose foram registrados entre 2010 e 2017. Destes, 145 (40,6%) tiveram confirmação laboratorial. Os casos ocorreram em indivíduos entre 7 e 73 anos de idade (média 34 anos; mediana 30 anos) com uma proporção de 4,2:1 entre os sexos masculino e feminino. Houve seis mortes durante o período estudado, com uma taxa de letalidade global de 4,1%. Não foi verificada uma relação entre localização geográfica (distrito) e incidência de leptospirose em Santa Lúcia. Foi observada uma fraca correlação entre a ocorrência de casos e precipitação no período considerado de 8 anos (rs = 0,25, p = 0,015), mas a correlação entre casos da doença e estações do ano não foi estatisticamente significativa (estação seca rs = 0,13, p = 0,42; estação chuvosa rs = 0,23, p = 0,08). Não foi verificada correlação entre leptospirose e temperatura (rs = 0,07, p = 0,49). Conclusões. A leptospirose tem distribuição sazonal em Santa Lúcia, com a ocorrência de surtos nos períodos que se seguem ao aumento da precipitação e às enchentes, como após tempestades tropicais e furacões. Santa Lúcia e os outros países do Caribe devem intensificar a vigilância da leptospirose diante da possibilidade de maior ocorrência de enchentes com as chuvas intensas e mais frequentes decorrentes da mudança climática.

Poly(methyl methacrylate) Films with High Concentrations of Silicon Quantum Dots for Visibly Transparent Luminescent Solar Concentrators.

Silicon quantum dots (Si QDs) are attractive, nontoxic luminophores for luminescent solar concentrators (LSCs). Here, we produced Si QD/poly(methyl methacrylate) (PMMA) films on glass by doctor-blading polymer solutions and achieved films with low light scattering at an order of magnitude higher Si QD weight fraction than has been achieved previously in the bulk. We suggest that the fast solidification rate of films as compared to slow bulk polymerization is an enabling factor in avoiding large agglomerates within the nanocomposites. Scanning electron microscopy confirmed that ∼100 nm or larger QD agglomerates exist in light-scattering films, and photoluminescence intensity measurements show that light scattering, if present, significantly reduces waveguiding efficiencies for LSCs. Nonscattering films fabricated in this work exhibit high ultraviolet absorption (>80%) paired with high visible transmission (>87%) and minimal visible haze (∼1%), making them well suited for semitransparent coatings for LSCs realized as solar harvesting windows.

Capillary Flow with Evaporation in Open Rectangular Microchannels.

Numerous applications rely upon capillary flow in microchannels for successful operation including lab-on-a-chip devices, porous media flows, and printed electronics manufacturing. Open microchannels often appear in these applications, and evaporation of the liquid can significantly affect its flow. In this work, we develop a Lucas-Washburn-type one-dimensional model that incorporates the effects of concentration-dependent viscosity and uniform evaporation on capillary flow in channels of a rectangular cross section. The model yields predictions of the time evolution of the liquid front down the length of the microchannel. For the case where evaporation is absent, prior studies have demonstrated better agreement between model predictions and experimental observations in low-viscosity liquids when using a no-slip rather than a no-stress boundary condition at the upper liquid-air interface. However, flow visualization experiments conducted in this work suggest the absence of a rigidified liquid-air interface. The use of the no-stress condition results in overestimation of the time evolution of the liquid front, which appears to be due to underestimation of the viscous forces from (i) the upper and front meniscus morphology, (ii) dynamic contact angle effects, and (iii) surface roughness, none of which are accounted for in the model. When high-viscosity liquids are considered, the large bulk viscosity is found to suppress these factors, resulting in better agreement between model predictions using the no-stress condition and experiments. Model predictions are also compared to prior experiments involving poly(vinyl alcohol) in the presence of evaporation by using the evaporation rate as a fitting parameter. Scaling relationships obtained from the model for the dependence of the final liquid-front position and total flow time on the channel dimensions and rate of uniform evaporation are found to be in good agreement with experimental observations.

Arbovirosis emergentes y reemergentes transmitidas por Aedes en la Región de las Américas: implicaciones en materia de políticas de salud / Emerging and reemerging Aedes-transmitted arbovirus infections in the Region of the Americas: implications for health policy

[RESUMEN]. El aumento en la incidencia y distribución geográfica de las arbovirosis constituye uno de los principales problemas de salud pública en la Región de las Américas. La incidencia del dengue ha experimentado una tendencia creciente en los últimos decenios en la Región, donde se ha pasado de una endemicidad baja a hiperendemicidad. También, la incidencia de la fiebre amarilla se ha intensificado en este período, y ha pasado de una actividad restringida a zonas selváticas a presentar brotes urbanos. El chikunguña comenzó a propagarse de forma pandémica en el 2005 a un ritmo sin precedentes y llegó al continente americano en el 2013. Al año siguiente, la infección por el virus del Zika irrumpió también en la Región con un brote explosivo acompañado de gravísimas anomalías congénitas y trastornos neurológicos, hasta convertirse en una de las mayores crisis de salud en los últimos años. La inadecuada vigilancia de las arbovirosis en la Región y la carencia de pruebas serológicas para diferenciar entre los distintos virus plantean retos considerables. Sigue habiendo pocas evidencias científicas en respaldo de las intervenciones de control de vectores. El manejo clínico sigue siendo la piedra angular del control de estas enfermedades. En la actualidad, solo están autorizadas en la Región de las Américas las vacunas contra la fiebre amarilla y contra el dengue, si bien hay varias vacunas experimentales en fase de investigación en ensayos clínicos. El Grupo Mundial de Expertos en Arbovirus ofrece en este artículo un panorama de los progresos, los retos y las recomendaciones sobre prevención y control de las arbovirosis en los países de la Región de las Américas.

[ABSTRACT]. The increasing geographical spread and disease incidence of arboviral infections are among the greatest public health concerns in the Americas. The region has observed an increasing trend in dengue incidence in the last decades, evolving from low to hyperendemicity. Yellow fever incidence has also intensified in this period, expanding from sylvatic-restricted activity to urban outbreaks. Chikungunya started spreading pandemically in 2005 at an unprecedented pace, reaching the Americas in 2013. The following year, Zika also emerged in the region with an explosive outbreak, carrying devastating congenital abnormalities and neurologic disorders and becoming one of the greatest global health crises in years. The inadequate arbovirus surveillance in the region and the lack of serologic tests to differentiate among viruses poses substantial challenges. The evidence for vector control interventions remains weak. Clinical management remains the mainstay of arboviral disease control. Currently, only yellow fever and dengue vaccines are licensed in the Americas, with several candidate vaccines in clinical trials. The Global Arbovirus Group of Experts provides in this article an overview of progress, challenges, and recommendations on arboviral prevention and control for countries of the Americas.

Emerging and Reemerging Aedes-Transmitted Arbovirus Infections in the Region of the Americas: Implications for Health Policy.

The increasing geographical spread and disease incidence of arboviral infections are among the greatest public health concerns in the Americas. The region has observed an increasing trend in dengue incidence in the last decades, evolving from low to hyperendemicity. Yellow fever incidence has also intensified in this period, expanding from sylvatic-restricted activity to urban outbreaks. Chikungunya started spreading pandemically in 2005 at an unprecedented pace, reaching the Americas in 2013. The following year, Zika also emerged in the region with an explosive outbreak, carrying devastating congenital abnormalities and neurologic disorders and becoming one of the greatest global health crises in years. The inadequate arbovirus surveillance in the region and the lack of serologic tests to differentiate among viruses poses substantial challenges. The evidence for vector control interventions remains weak. Clinical management remains the mainstay of arboviral disease control. Currently, only yellow fever and dengue vaccines are licensed in the Americas, with several candidate vaccines in clinical trials. The Global Arbovirus Group of Experts provides in this article an overview of progress, challenges, and recommendations on arboviral prevention and control for countries of the Americas.

Zika virus outbreak in 19 English- and Dutch-speaking Caribbean countries and territories, 2015–2016

[ABSTRACT]. Surveillance for Zika virus was enhanced in the English- and Dutch-speaking Caribbean following emergence of the virus in Brazil in May 2015. The first autochthonous case of Zika in the Caribbean was reported by Suriname in November 2015, and the virus subsequently spread rapidly throughout the region. Caribbean Public Health Agency (CARPHA) member states (CMS) reported clinically suspected cases of Zika and submitted serum specimens to the agency for laboratory investigation. A patient was considered a confirmed case if Zika virus was detected by real-time reverse transcription–polymerase chain reaction (RT-PCR) assay or serological test. Due to the documented link between 1) Zika virus and congenital syndrome, and 2) Zika virus and Guillain–Barré syndrome (GBS), data on both of these disease outcomes were extracted from country and regional reports. This special report describes the epidemiology of laboratory-confirmed Zika cases reported to CARPHA, including links with both congenital syndrome and GBS, for 19 English- and Dutch-speaking Caribbean countries during the epidemic period (1 October 2015–29 December 2016).

[RESUMEN]. Tras la aparición del virus del Zika en Brasil en mayo del 2015, los países de habla inglesa y holandesa reforzaron la vigilancia de este virus. El primer caso autóctono de infección por el virus del Zika en el Caribe fue notificado por Suriname en noviembre del 2015 y desde entonces el virus se ha propagado rápidamente en toda el área. Los Estados Miembros del Organismo de Salud Pública del Caribe (CARPHA, por su sigla en inglés) notificaron casos presuntos de infección por el virus detectados clínicamente y entregaron al Organismo muestras de suero para que se llevaran a cabo las pruebas de laboratorio. Se consideró que un paciente era un caso confirmado si se detectaba el virus del Zika mediante la prueba serológica de la reacción en cadena de la polimerasa con retrotranscriptasa en tiempo real. Habida cuenta de la relación documentada entre 1) el virus del Zika y el síndrome congénito y 2) el virus del Zika y el síndrome de Guillain Barré, se buscaron datos sobre los resultados relativos a ambas enfermedades en los informes nacionales y regionales. En este informe especial se describen las características epidemiológicas de los casos de infección por el virus del Zika notificados al CARPHA, confirmados mediante pruebas de laboratorio, incluidos los vínculos con el síndrome congénito y el síndrome de Guillain Barré, en 19 países del Caribe de habla inglesa y holandesa en el período de la epidemia (del 1 de octubre del 2015 al 29 de diciembre del 2016).

[RESUMO]. A vigilância do zika foi melhorada nos países e territórios do Caribe de língua inglesa e holandesa com a emergência da doença no Brasil em maio de 2015. O primeiro caso autóctone de zika no Caribe foi registrado no Suriname em novembro de 2015 e, desde então, o vírus tem se propagado rapidamente em toda a região. Os Estados Membros da Agência de Saúde Pública do Caribe (CARPHA) notificaram casos com suspeita clínica de zika e enviaram amostras séricas para análise laboratorial. Considerou-se caso confirmado quando houve a detecção do vírus zika com a técnica de reação em cadeia da polimerase da transcrição reversa em tempo real (PCR-RT) ou com teste sorológico. Devido à associação comprovada entre o vírus zika e a síndrome congênita e o vírus zika e a síndrome de Guillain–Barré (SGB), foram obtidos dados relativos a estes desfechos dos registros regionais e dos países. Este informe especial faz uma descrição da epidemiologia dos casos de zika com confirmação laboratorial notificados à CARPHA, incluindo casos associados à síndrome congênita e SGB, nos 19 países do Caribe de língua inglesa e holandesa no período epidêmico (de 1o de outubro de 2015 a 29 de dezembro de 2016).

Capillary Coatings: Flow and Drying Dynamics in Open Microchannels.

Capillary flow and drying of polymer solutions in open microchannels are explored over time scales spanning seven orders of magnitude: from capillary filling (10-3-10 s) to the formation of a dry thin film (a "capillary coating"; 102-103 s). During capillary filling, drying-induced changes (increased solids content and viscosity) generate microscale pinning events that impede contact line motion. Three unique types of pinning are identified and characterized, each defined by the specific location(s) along the contact line at which pinning is induced. Drying is shown to ultimately pin the contact line permanently, and the associated total flow distances and times are revealed to be strong functions of channel width and drying rate. In general, lower drying rates coupled with intermediate channel widths are found to be most conducive to longer flow distances and times. After the advancing contact line permanently pins, internal flows driven by uneven evaporation rates continue to drive polymer to the contact line. This phenomenon promotes a local accumulation of solids and persists until all motion is arrested by drying. The effects of channel width and drying rate are investigated at each stage of this capillary coating process. These results are then applied to case studies of two functional inks commonly used in printed electronics fabrication: a PEDOT:PSS (poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)) ink and a graphene ink. Although drying is shown to permanently arrest flow in both inks, both systems exhibit an increased resistance to pinning unexplained by mechanisms identified in aqueous polymer systems. Instead, arguments based on chemistry, particle size, and rheology are used to explain their novel behavior. These case studies provide insight into how functional inks can be better designed to optimize flow distances and maximize overall dry film uniformity in capillary coatings.

Zika virus outbreak in 19 English- and Dutch-speaking Caribbean countries and territories, 2015-2016.

Surveillance for Zika virus was enhanced in the English- and Dutch-speaking Caribbean following emergence of the virus in Brazil in May 2015. The first autochthonous case of Zika in the Caribbean was reported by Suriname in November 2015, and the virus subsequently spread rapidly throughout the region. Caribbean Public Health Agency (CARPHA) member states (CMS) reported clinically suspected cases of Zika and submitted serum specimens to the agency for laboratory investigation. A patient was considered a confirmed case if Zika virus was detected by real-time reverse transcription-polymerase chain reaction (RT-PCR) assay or serological test. Due to the documented link between 1) Zika virus and congenital syndrome, and 2) Zika virus and Guillain-Barré syndrome (GBS), data on both of these disease outcomes were extracted from country and regional reports. This special report describes the epidemiology of laboratory-confirmed Zika cases reported to CARPHA, including links with both congenital syndrome and GBS, for 19 English- and Dutch-speaking Caribbean countries during the epidemic period (1 October 2015-29 December 2016).

Tras la aparición del virus del Zika en Brasil en mayo del 2015, los países de habla inglesa y holandesa reforzaron la vigilancia de este virus. El primer caso autóctono de infección por el virus del Zika en el Caribe fue notificado por Suriname en noviembre del 2015 y desde entonces el virus se ha propagado rápidamente en toda el área. Los Estados Miembros del Organismo de Salud Pública del Caribe (CARPHA, por su sigla en inglés) notificaron casos presuntos de infección por el virus detectados clínicamente y entregaron al Organismo muestras de suero para que se llevaran a cabo las pruebas de laboratorio. Se consideró que un paciente era un caso confirmado si se detectaba el virus del Zika mediante la prueba serológica de la reacción en cadena de la polimerasa con retrotranscriptasa en tiempo real. Habida cuenta de la relación documentada entre 1) el virus del Zika y el síndrome congénito y 2) el virus del Zika y el síndrome de Guillain Barré, se buscaron datos sobre los resultados relativos a ambas enfermedades en los informes nacionales y regionales. En este informe especial se describen las características epidemiológicas de los casos de infección por el virus del Zika notificados al CARPHA, confirmados mediante pruebas de laboratorio, incluidos los vínculos con el síndrome congénito y el síndrome de Guillain Barré, en 19 países del Caribe de habla inglesa y holandesa en el período de la epidemia (del 1 de octubre del 2015 al 29 de diciembre del 2016).

A vigilância do zika foi melhorada nos países e territórios do Caribe de língua inglesa e holandesa com a emergência da doença no Brasil em maio de 2015. O primeiro caso autóctone de zika no Caribe foi registrado no Suriname em novembro de 2015 e, desde então, o vírus tem se propagado rapidamente em toda a região. Os Estados Membros da Agência de Saúde Pública do Caribe (CARPHA) notificaram casos com suspeita clínica de zika e enviaram amostras séricas para análise laboratorial. Considerou-se caso confirmado quando houve a detecção do vírus zika com a técnica de reação em cadeia da polimerase da transcrição reversa em tempo real (PCR-RT) ou com teste sorológico. Devido à associação comprovada entre o vírus zika e a síndrome congênita e o vírus zika e a síndrome de Guillain­Barré (SGB), foram obtidos dados relativos a estes desfechos dos registros regionais e dos países. Este informe especial faz uma descrição da epidemiologia dos casos de zika com confirmação laboratorial notificados à CARPHA, incluindo casos associados à síndrome congênita e SGB, nos 19 países do Caribe de língua inglesa e holandesa no período epidêmico (de 1o de outubro de 2015 a 29 de dezembro de 2016).

Zika virus outbreak in 19 English- and Dutch-speaking Caribbean countries and territories, 2015-2016 / Brote epidémico del virus del Zika en 19 países y territorios del Caribe de habla inglesa y holandesa en el período 2015-2016 / Surto causado pelo vírus zika em 19 países e territórios do Caribe de língua inglesa e holandesa, 2015-2016

ABSTRACT Surveillance for Zika virus was enhanced in the English- and Dutch-speaking Caribbean following emergence of the virus in Brazil in May 2015. The first autochthonous case of Zika in the Caribbean was reported by Suriname in November 2015, and the virus subsequently spread rapidly throughout the region. Caribbean Public Health Agency (CARPHA) member states (CMS) reported clinically suspected cases of Zika and submitted serum specimens to the agency for laboratory investigation. A patient was considered a confirmed case if Zika virus was detected by real-time reverse transcription-polymerase chain reaction (RT-PCR) assay or serological test. Due to the documented link between 1) Zika virus and congenital syndrome, and 2) Zika virus and Guillain-Barré syndrome (GBS), data on both of these disease outcomes were extracted from country and regional reports. This special report describes the epidemiology of laboratory-confirmed Zika cases reported to CARPHA, including links with both congenital syndrome and GBS, for 19 English- and Dutch-speaking Caribbean countries during the epidemic period (1 October 2015-29 December 2016).

RESUMEN Tras la aparición del virus del Zika en Brasil en mayo del 2015, los países de habla inglesa y holandesa reforzaron la vigilancia de este virus. El primer caso autóctono de infección por el virus del Zika en el Caribe fue notificado por Suriname en noviembre del 2015 y desde entonces el virus se ha propagado rápidamente en toda el área. Los Estados Miembros del Organismo de Salud Pública del Caribe (CARPHA, por su sigla en inglés) notificaron casos presuntos de infección por el virus detectados clínicamente y entregaron al Organismo muestras de suero para que se llevaran a cabo las pruebas de laboratorio. Se consideró que un paciente era un caso confirmado si se detectaba el virus del Zika mediante la prueba serológica de la reacción en cadena de la polimerasa con retrotranscriptasa en tiempo real. Habida cuenta de la relación documentada entre 1) el virus del Zika y el síndrome congénito y 2) el virus del Zika y el síndrome de Guillain Barré, se buscaron datos sobre los resultados relativos a ambas enfermedades en los informes nacionales y regionales. En este informe especial se describen las características epidemiológicas de los casos de infección por el virus del Zika notificados al CARPHA, confirmados mediante pruebas de laboratorio, incluidos los vínculos con el síndrome congénito y el síndrome de Guillain Barré, en 19 países del Caribe de habla inglesa y holandesa en el período de la epidemia (del 1 de octubre del 2015 al 29 de diciembre del 2016).

RESUMO A vigilância do zika foi melhorada nos países e territórios do Caribe de língua inglesa e holandesa com a emergência da doença no Brasil em maio de 2015. O primeiro caso autóctone de zika no Caribe foi registrado no Suriname em novembro de 2015 e, desde então, o vírus tem se propagado rapidamente em toda a região. Os Estados Membros da Agência de Saúde Pública do Caribe (CARPHA) notificaram casos com suspeita clínica de zika e enviaram amostras séricas para análise laboratorial. Considerou-se caso confirmado quando houve a detecção do vírus zika com a técnica de reação em cadeia da polimerase da transcrição reversa em tempo real (PCR-RT) ou com teste sorológico. Devido à associação comprovada entre o vírus zika e a síndrome congênita e o vírus zika e a síndrome de Guillain-Barré (SGB), foram obtidos dados relativos a estes desfechos dos registros regionais e dos países. Este informe especial faz uma descrição da epidemiologia dos casos de zika com confirmação laboratorial notificados à CARPHA, incluindo casos associados à síndrome congênita e SGB, nos 19 países do Caribe de língua inglesa e holandesa no período epidêmico (de 1o de outubro de 2015 a 29 de dezembro de 2016).

Chikungunya virus outbreak in Sint Maarten, 2013-2014.

This report describes the outbreak of chikungunya virus (CHIKV) in Sint Maarten, a constituent country of Kingdom of the Netherlands comprising the southern part of the Caribbean island of Saint Martin, from 22 December 2013 (first reported case) through 5 December 2014. The outbreak was first reported by the French overseas collectivity of Saint-Martin in the northern part of the island-the first site in the Americas to report autochthonous transmission of CHIKV. By 5 December 2014, Sint Maarten had reported a total of 658 cases-an overall attack rate of 1.76%. Actual prevalence may have been higher, as some cases may have been misdiagnosed as dengue. Fever and arthralgia affected 71% and 69% of reported cases respectively. Of the 390 laboratory-confirmed cases, 61% were female and the majority were 20-59 years old (mean: 42; range: 4-92). The spread of CHIKV to Sint Maarten was inevitable given the ease of movement of people, and the vector, island-wide. Continuing their history of collaboration, the French and Dutch parts of the island coordinated efforts for prevention and control of the disease. These included a formal agreement to exchange epidemiological information on a regular basis and provide alerts in a timely manner; collaboration among personnel through joint island-wide planning of mosquito control activities, especially along borders; notification of all island visitors, upon their arrival at airports and seaports, of preventative measures to avoid being bitten by mosquitoes; dissemination of educational materials to the public; and island-wide public awareness campaigns, particularly in densely populated areas, for both residents and visitors. The information provided in this report could help increase understanding of the epidemiological characteristics of CHIKV and guide other countries dealing with vector-borne epidemics.

Chikungunya virus outbreak in Sint Maarten, 2013–2014 / Brote de virus del chikungunya en Sint Maarten, 2013–2014

This report describes the outbreak of chikungunya virus (CHIKV) in Sint Maarten, a constituent country of Kingdom of the Netherlands comprising the southern part of the Caribbean island of Saint Martin, from 22 December 2013 (first reported case) through 5 December 2014. The outbreak was first reported by the French overseas collectivity of Saint-Martin in the northern part of the island—the first site in the Americas to report autochthonous transmission of CHIKV. By 5 December 2014, Sint Maarten had reported a total of 658 cases—an overall attack rate of 1.76%. Actual prevalence may have been higher, as some cases may have been misdiagnosed as dengue. Fever and arthralgia affected 71% and 69% of reported cases respectively. Of the 390 laboratory-confirmed cases, 61% were female and the majority were 20–59 years old (mean: 42; range: 4–92). The spread of CHIKV to Sint Maarten was inevitable given the ease of movement of people, and the vector, island-wide. Continuing their history of collaboration, the French and Dutch parts of the island coordinated efforts for prevention and control of the disease. These included a formal agreement to exchange epidemiological information on a regular basis and provide alerts in a timely manner; collaboration among personnel through joint island-wide planning of mosquito control activities, especially along borders; notification of all island visitors, upon their arrival at airports and seaports, of preventative measures to avoid being bitten by mosquitoes; dissemination of educational materials to the public; and island-wide public awareness campaigns, particularly in densely populated areas, for both residents and visitors. The information provided in this report could help increase understanding of the epidemiological characteristics of CHIKV and guide other countries dealing with vector- borne epidemics.

En el presente artículo se describe el brote del virus del chikungunya (CHIKV) que tuvo lugar entre el 22 de diciembre del 2013 (primer caso notificado) y el 5 de diciembre del 2014 en Sint Maarten, uno de los países integrantes del Reino de los Países Bajos, que comprende la parte sur de la isla caribeña de San Martín. El brote fue notificado primero por la colectividad de ultramar francesa de Saint-Martin, que ocupa la parte norte de la isla, convirtiéndose en la primera zona de las Américas en describir la transmisión autóctona del CHIKV. El 5 de diciembre del 2014, Sint Maarten había notificado 658 casos, equivalentes a una tasa de ataque del 1,76%, si bien la prevalencia real quizá haya sido mayor, puesto que algunos casos pueden haberse confundido por dengue. El 71% y el 69% de los casos notificados cursaron con fiebre y artralgias, respectivamente. De los 390 casos confirmados por laboratorio, el 61% eran mujeres y la mayoría tenían entre 20 y 59 años de edad (media: 42; intervalo: 4-92). Era inevitable que el CHIKV pasara a Sint Maarten, dadas la facilidad de movimiento de las personas y la extensión del vector por toda la isla. Siguiendo la tradición de cooperación mutua, las partes francesa y holandesa de la isla coordinaron las actuaciones de prevención y control, que consistieron en: la formalización de un convenio para intercambiar datos epidemiológicos de forma regular y emitir alertas puntualmente; la colaboración del personal de uno y otro lado para planificar, en todo el territorio insular, las actividades de control de mosquitos, sobre todo a lo largo de las fronteras; la notificación a todos los viajeros en arribo, a su llegada a los puertos y aeropuertos, de las medidas preventivas para evitar la picadura de los mosquitos; la difusión de materiales didácticos; y la realización de campañas públicas de concientización por toda la isla, en particular en las áreas de mayor densidad demográfica, dirigidas tanto a residentes como a turistas. La información expuesta en este informe puede ayudar a conocer mejor las características epidemiológicas del CHIKV y servir de orientación para otros países que hagan frente a epidemias transmitidas por vectores.

ZnO Nanocrystal Networks Near the Insulator-Metal Transition: Tuning Contact Radius and Electron Density with Intense Pulsed Light.

Networks of ligand-free semiconductor nanocrystals (NCs) offer a valuable combination of high carrier mobility and optoelectronic properties tunable via quantum confinement. In principle, maximizing carrier mobility entails crossing the insulator-metal transition (IMT), where carriers become delocalized. A recent theoretical study predicted that this transition occurs at nρ3 ≈ 0.3, where n is the carrier density and ρ is the interparticle contact radius. In this work, we satisfy this criterion in networks of plasma-synthesized ZnO NCs by using intense pulsed light (IPL) annealing to tune n and ρ independently. IPL applied to as-deposited NCs increases ρ by inducing sintering, and IPL applied after the NCs are coated with Al2O3 by atomic layer deposition increases n by removing electron-trapping surface hydroxyls. This procedure does not substantially alter NC size or composition and is potentially applicable to a wide variety of nanomaterials. As we increase nρ3 to at least twice the predicted critical value, we observe conductivity scaling consistent with arrival at the critical region of a continuous quantum phase transition. This allows us to determine the critical behavior of the dielectric constant and electron localization length at the IMT. However, our samples remain on the insulating side of the critical region, which suggests that the critical value of nρ3 may in fact be significantly higher than 0.3.

High-Resolution Transfer Printing of Graphene Lines for Fully Printed, Flexible Electronics.

Pristine graphene inks show great promise for flexible printed electronics due to their high electrical conductivity and robust mechanical, chemical, and environmental stability. While traditional liquid-phase printing methods can produce graphene patterns with a resolution of ∼30 µm, more precise techniques are required for improved device performance and integration density. A high-resolution transfer printing method is developed here capable of printing conductive graphene patterns on plastic with line width and spacing as small as 3.2 and 1 µm, respectively. The core of this method lies in the design of a graphene ink and its integration with a thermally robust mold that enables annealing at up to ∼250 °C for precise, high-performance graphene patterns. These patterns exhibit excellent electrical and mechanical properties, enabling favorable operation as electrodes in fully printed electrolyte-gated transistors and inverters with stable performance even following cyclic bending to a strain of 1%. The high resolution coupled with excellent control over the line edge roughness to below 25 nm enables aggressive scaling of transistor dimensions, offering a compelling route for the scalable manufacturing of flexible nanoelectronic devices.

Modulus- and Surface-Energy-Tunable Thiol-ene for UV Micromolding of Coatings.

Micromolding of UV-curable materials is a patterning method to fabricate microstructured surfaces that is an additive manufacturing process fully compatible with roll-to-roll systems. The development of micromolding for mass production remains a challenge because of the multifaceted demands of UV curable materials and the risk of demolding-related defects, particularly when patterning high-aspect-ratio features. In this research, a robust micromolding approach is demonstrated that integrates thiol-ene polymerization and UV LED curing. The moduli of cured thiol-ene coatings were tuned over 2 orders of magnitude by simply adjusting the acrylate concentration of a coating formulation, the curing completed in all cases within 10 s of LED exposure. Densely packed 50-µm-wide gratings were faithfully replicated in coatings ranging from soft materials to stiff highly cross-linked networks. Further, surface energy was modified with a fluorinated polymer, achieving a surface energy reduction of more than a half at a loading of 1 wt %, and enabling tall (100 µm) defect-free patterns to be attained. The demolding strengths of microstructured coatings were compared using quantitative peel testing, showing its decrease with decreasing surface energy, coating modulus, and grating height. This micromolding process, combining tunability in thermomechanical and surface properties, makes thiol-ene microstructured coatings attractive candidates for roll-to-roll manufacture. As a demonstration of the utility of the process, superhydrophobic surfaces are prepared using the system modified by the fluorinated polymer.