Despite being considered beneficial by providing a clean and renewable source of energy, the construction of hydroelectric dams has extremely negative implications for Amazonian fisheries. This study ...investigated the impacts of the Santo Antônio and Jirau hydroelectric dams on the fishery stocks of the Madeira River. This investigation was based on fish catch data from the Z‐31 fishing colony, located in the municipality of Humaitá, in Amazonas State, Northern Brazil. Data were collected daily and provided information on the date of return from each trip, the fish species targeted, and the total catch (kg) between January 2002 and September 2017. The results indicated reductions of 39% in the mean annual catch and 34% in the mean monthly catches. These results highlight the high price paid by local fish communities for the development of hydroelectric power in the Amazon basin.
► We study fire activity over Mediterranean Europe based on data from Meteosat-8. ► We assess the role played by land cover and by weather conditions on fire events. ► The vast majority of persistent ...fire events occur in forest and shrub. ► We propose a conceptual model for weather conditions favouring severe fire events. ► Results pave the way to the generation of daily calibrated maps of fire risk.
Mediterranean regions are some of the most affected by wildfires and remote-sensed information about fire activity, as provided by the SEVIRI instrument on-board Meteosat-8, is especially valuable for forest and civil protection activities. An analysis is performed of the spatial distribution of fire events during the period of July and August 2007–2009. Around half of fire pixels were detected in croplands, the remaining half being evenly distributed between forest and shrub, as opposed to the distribution of persistent fire events (more than 10h of duration) where 90% occurred in forest and shrub, evenly distributed between these two classes. With slightly more than half of the fire events and the most severe episodes, the year of 2007 is the most serious, allowing an assessment of the role of meteorological conditions on large fire events based on the analysis of low, mid and upper atmospheric fields of geopotential, temperature, relative humidity and wind. The analysis of two extreme events of fire activity that struck Greece and Italy on 24–25 July and 22–27 August, 2007 suggested a conceptual model for meteorological conditions favouring the occurrence of severe wildfire episodes in Italy and the Balkan Peninsula. On the one hand there is, at the surface, strong northerly advection of very hot and very dry air over the region, as steered by the presence of a ridge over central Europe together with a thermal depression over southwest Asia. On the other hand, the air advected is further heated by adiabatic compression associated to strong subsidence from around 700 up to 250hPa, associated to the presence of a ridge over the Eastern Mediterranean and to the anomalous displacement of the jet streak towards the northwest. The importance of both short- and long-term atmospheric conditions on meteorological fire risk is also put into evidence by analyzing the fields of three weather-based indices, namely the Build-Up Index, the Initial Spread Index and the Fire Weather Index that are part of the Canadian Forest Fire Weather Index System. Identified links of fire onset and fire persistence with land cover types and with atmospheric circulation patterns suggest using data on fire activity as derived from Meteosat-8/SEVIRI to generate statistically calibrated maps of fire risk in Mediterranean Europe.
We investigated the effects of increase in sampling effort (30–1043 sampling points) on the accuracy of assessment of the spatial patterns of surface-water quality in a eutrophic tropical reservoir. ...The investigation was carried out during the dry season, when previous investigations showed that the spatial heterogeneity is more stable. A multi-parameter Yellow Springs Instruments probe coupled to a TechGeo D-GPS was used. This system is equipped to measure and store in a continuous recording mode, several physical and chemical parameters linked to geographical coordinates obtained with a precision of less than 1
m. We used different geostatistical approaches to determine the optimal number of sampling points required to reflect the real spatial patterns of water quality in the system. This approach was tested in a small tropical reservoir (Ibirité) that receives effluents from an oil refinery (the state-owned REGAP oil refinery, PETROBRAS) located near the city of Belo Horizonte. The study showed not only that the spatial patterns of water quality are significantly affected by sampling effort but also it was demonstrated that the establishment of an adequate sampling program is a critical point for the precise identification of source points of pollution. The results of this investigation enabled us to demonstrate the potential uses and limits of this method for rapid assessment of the water quality of lakes and reservoirs that receive external inputs of water contaminants or nutrients.
Abundance, biomass, production, and grazing loss rates of phytoplankton, free-living bacteria, and Protozoa were assessed during an intense spring phytoplankton bloom in prealpine Lake Constance ...(Bodensee). More than 50% of the primary production was channeled through the microbial loop. Bacteria and ciliates responded rapidly to increasing phytoplankton biomass and production. Maximal growth rates of bacteria and Protozoa were slightly lower than those of the dominating phytoplankton species. Averaged over the spring bloom, bacterial C amounted to 21% of phytoplankton C, bacterial production to 18% of particulate primary production. Increase of heterotrophic flagellate populations was prevented by grazing within the microbial loop, probably mainly by the feeding impact of ciliates. Although ciliates controlled flagellate production, they satisfied their food demand primarily by feeding on algae and consumed $\thicksim 14%$ of primary production. Metazoan microzooplankton (copepod nauplii and rotifers) removed $\thicksim 7%$ of the phytoplankton production. Herbivorous metazooplankton ingested slightly less. Therefore, the phytoplankton bloom was not terminated by excess grazing. $PO_4^3-$ depletion and subsequent sedimentation was most likely the prime cause for the termination of the spring bloom.
To be eligible for government-provided treatment in Brazil, all HCV-infected individuals are required to be genotyped shortly after diagnosis. We describe the HCV genotype (G) profiles by geographic ...region, gender, age and HIV co-infection.
We assessed 29,071 genotypes collected from HCV-infected individuals from March 2016 to March 2018 (Abbott Real-Time HCV Genotype). We randomly selected 12,336 samples for HIV co-infection testing using an EIA rapid test kit (TR DPP HIV 1/2 Bio-Manguinhos). Descriptive statistical analyses were performed using R.
Overall, HCV genotype distribution was 40.9% G1A, 30.2% G1B, 23.8% G3, 3.8% G2, 0.7% G4, 0.1% G5 and 0.6% with multiples genotypes. G1A prevalence was 44.4% among males and 35.8% among females. G1B and G2 were more prevalent in older individuals than G1A and G3. G3 was more prevalent in the South region. Of samples tested for HIV co-infection, 15% were HIV+. Median age among HCV/HIV co-infected individuals was 50 years old compared to 57 years old among mono-infected individuals. Distinct HCV genotype prevalence between HCV/HIV co-infected and HCV mono-infected individuals were respectively: G1A 60.6% versus 37.8%, G1B 15.2% versus 32.9%, and G3 18.9% versus 24.7%. G4 was detected among co-infected young men (3.5% versus 0.2% among mono-infected).
The increasing prevalence of G3, as inferred by the younger ages of the HCV-infected individuals, poses an extra challenge with regards to disease progression. Distinct genotypical profiles between HCV mono-infection and HCV/HIV co-infection warrant future research in order to better understand and help mitigate HCV chains of transmission.
To compare the analgesic efficacy of 2 types of anesthetic techniques-topical and topical associated with cryoanalgesia-during cataract surgery.
Department of Ophthalmology, University of São Paulo, ...Ribeirão Preto, Brazil.
Prospective randomized study.
Patients with symmetrical bilateral cataract had phacoemulsification with the use of an intraocular irrigation solution at room temperature in 1 eye and a cold (4°C) solution in the contralateral eye (Group 2). The pain related to the procedure was assessed using a visual analog scale ranging from 0 to 100, with 0 representing no pain and 100 the worst pain. In addition, endothelial cell loss, the change in corneal thickness, and visual acuity were evaluated 30 days ± 2 (SD) after each surgery. The surgery duration, total irrigation volume, phacoemulsification time, and ultrasound power used were analyzed.
The study enrolled 25 patients (50 eyes). There was no statistically significant difference in the mean pain score between Group 1 (26.0 ± 3.7) and Group 2 (21.3 ± 3.6) (P = .2016, paired t test). No significant difference was found in the mean corneal endothelial cell loss (Group 1: 10.0% ± 0.4%; Group 2: 9.9% ± 0.3%; P = .7576), corneal thickness increase (Group 1: 1.5 ± 1.0 μm; Group 2: 1.4 ± 0.9 μm; P = .9340), or visual acuity gain (Group 1: 0.54 ± 0.06 logMAR; Group 2: 0.55 ± 0.09 logMAR; P = .8208).
There is no difference in the intensity of pain during phacoemulsification with the use of topical anesthesia or topical anesthesia associated with cryoanalgesia.
No author has a financial or proprietary interest in any material or method mentioned.
Photothermal response of plasmonic nanomaterials can be utilized for a number of therapeutic applications such as the ablation of solid tumors.
Gold nanoparticles were prepared using different ...methods. After optimization, we applied an aqueous plant extract as the reducing and capping agent of gold and maximized the near-infrared absorption (650-900 nm). Resultant nanoparticles showed good biocompatibility when tested in vitro in human keratinocytes and yeast Saccharomyces cerevisiae. Gold nanoparticles were easily activated by controlled temperature with an ultrasonic water bath and application of a pulsed laser.
These gold nanoparticles can be synthesized with reproducibility, modified with seemingly limitless chemical functional groups, with adequate controlled optical properties for laser phototherapy of tumors and targeted drug delivery.
This study describes a new ecological association between two typical components of tropical freshwater zooplankton: the cladoceran (Bosmina longirostris) and the rotifer (Hexarthra intermedia), ...which, unlike those reported in the literature, led to mortal damage to the cladoceran.
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