Monitoring a critical population of the Bolivian river dolphin, Inia boliviensis, before and after closing the floodgates of a hydroelectric dam in the Amazon Basin, Brazil: A quantitative Analysis

Abstract The Belo Monte hydroelectric dam on the Xingu River has the third largest generating capacity of any hydroelectric dam in the world. We conducted surveys of crocodilians (Caiman crocodilus, Paleosuchus trigonatus) by boat in the Xingu River at the site of the dam prior to (2013-2015), and after filling (2016-2017). While the number of C. crocodilus sighted decreased with increasing water level, there was no difference in numbers prior to, and after reservoir filling. The number of P. trigonatus was unaffected by both water level prior to and after reservoir filling. Reservoir filling had little effect on the number of crocodilians using the forest around the Xingu River reservoir. Most crocodilians seen in forest surveys were P. trigonatus, both before and after reservoir filling, but C. crocodilus was recorded occasionally in the forest. It seems that most Amazonian crocodilians are sufficiently generalist to adapt to the new conditions created by the construction of dams, at least in the short-term. However, there may be long-term collateral effects on crocodilian populations from dams, due to as deforestation and improved access for hunters.

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Diet of Bryconops alburnoides and B. caudomaculatus (Osteichthyes: Characiformes) in the region affected by Balbina Hydroelectric Dam (Amazon drainage, Brazil)

Neotropical Ichthyology ◽

10.1590/s1679-62252008000200011 ◽

2008 ◽

Vol 6 (2) ◽

pp. 237-242 ◽

Cited By ~ 7

Author(s):

Cylene C. da Silva ◽

Efrem J. G. Ferreira ◽

Cláudia P. de Deus

Keyword(s):

Heavy Rainfall ◽

Amazon Basin ◽

Relative Volume ◽

Fish Diet ◽

Frequency Of Occurrence ◽

Important Data ◽

Hydroelectric Dam ◽

Morisita Index ◽

Terrestrial Insects ◽

And Behavior

The study of fish diet and its interaction with the environment provides important data on ecology and behavior, as fish face varying environmental and food availability conditions. The aim of the present study was to determine the diet of Bryconops caudomaculatus and Bryconops alburnoides, as well as to assess its seasonal variation, within the area influenced by Balbina Hydroelectric Dam (BHD), in the Uatumã River (Amazon Basin, Brazil). Collections were carried out every two months from April 2005 to February 2007, using gill nets with mesh sizes ranging from 12 to 60 mm between opposite knots. Two methods were used for determining diet: frequency of occurrence and relative volume, which were used to calculate the alimentary index (IAi). Diet similarity between species was analyzed by applying the Morisita index. Bryconops alburnoides ingested 12 items and B. caudomaculatus 10, with a 59% similarity between ingested items. Terrestrial insects for B. alburnoides and immature insects for B. caudomaculatus were the main items in their diets, and therefore, they were considered insectivorous. The seasonal composition of the diet of B. alburnoides was influenced by environmental factors, and in spite of the dominance of immature insects, it had a significant number of terrestrial insects during the heavy rainfall periods.

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Effectiveness of unmanned aerial vehicles to detect Amazon dolphins

Oryx ◽

10.1017/s0030605319000279 ◽

2019 ◽

Vol 54 (5) ◽

pp. 696-698 ◽

Cited By ~ 1

Author(s):

Marcelo Oliveira-da-Costa ◽

Miriam Marmontel ◽

Daiane S. X. da-Rosa ◽

André Coelho ◽

Serge Wich ◽

...

Keyword(s):

Unmanned Aerial Vehicles ◽

Amazon Basin ◽

Accurate Estimate ◽

Amazon River ◽

Tropical Rivers ◽

River Dolphin ◽

Aerial Vehicles ◽

Aerial Surveys ◽

Inia Geoffrensis ◽

Management And Conservation

AbstractQuantifying the abundance of species is essential for their management and conservation. Much effort has been invested in surveys of freshwater dolphins in the Amazon basin but river dimensions and complex logistics limit replication of such studies across the region. We evaluated the effectiveness of using unmanned aerial vehicles (UAVs) for surveying two Amazon dolphin species, the tucuxi Sotalia fluviatilis and pink river dolphin Inia geoffrensis, in tropical rivers. In 2016 we conducted drone and visual surveys over 80 km of the Juruá River in Brazil. The aerial surveys provided higher accuracy than human observers in counting individuals detected in groups. Compared to estimates derived from visual surveys, the use of UAVs could provide a more feasible, economical and accurate estimate of Amazon river dolphin populations. The method could potentially be replicated in other important areas for the conservation of these species, to generate an improved index of river dolphin populations in the Amazon.

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Advanced Telematics for Travel Decisions: A Quantitative Analysis of the Stopwatch Project in Southampton

Environment and Planning A Economy and Space ◽

10.1068/a291003 ◽

1997 ◽

Vol 29 (6) ◽

pp. 1003-1016 ◽

Cited By ~ 3

Author(s):

H Ouwersloot ◽

P Nijkamp ◽

G Pepping

Keyword(s):

Quantitative Analysis ◽

Theoretical Model ◽

Cost Minimization ◽

Information Service ◽

Uncertainty Reduction ◽

Two Samples ◽

Before And After ◽

Travel Decisions ◽

Reduction Of Uncertainty ◽

New System

The effect of telematics technology on public transport use is analyzed on the basis of a theoretical model. Two possible mechanisms (reduction of uncertainty and a better choice of bus options, based on a general cost-minimization assumption) that may stimulate bus use are distinguished. The model is empirically tested by using microdata from the Southampton Stopwatch telematics project, which were collected both before and after the introduction of this telematics information service. The estimation of the model leads to interesting findings in explaining (anticipated) increases in bus use, for both the before and the after survey. It is shown that uncertainty reduction is the more important effect of the new system. Differences in the before and after data are found concerning the increase in bus use, but the explanatory model proves consistent over the two samples.

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Quantitative Analysis of the Seminal Plasma Proteome in Secondary Hypogonadism

Journal of Clinical Medicine ◽

10.3390/jcm8122128 ◽

2019 ◽

Vol 8 (12) ◽

pp. 2128 ◽

Cited By ~ 1

Author(s):

Giuseppe Grande ◽

Federica Vincenzoni ◽

Francesca Mancini ◽

Ferran Barrachina ◽

Antonella Giampietro ◽

...

Keyword(s):

Quantitative Analysis ◽

Seminal Plasma ◽

Control Group ◽

Testosterone Replacement Therapy ◽

Male Hypogonadism ◽

Grey Zone ◽

Label Free ◽

Clinical Markers ◽

Before And After ◽

Secondary Hypogonadism

In the grey zone of testosterone levels between 8 and 12 nmol/L, the usefulness of therapy is controversial; as such, markers of tissue action of androgens may be helpful in adjusting clinical decisions. To better understand the effect of the hypothalamic-pituitary-testicular axis on male accessory secretion, we performed a proteomic quantitative analysis of seminal plasma in patients with secondary hypogonadism, before and after testosterone replacement therapy (TRT). Ten male patients with postsurgical hypogonadotrophic hypogonadism were enrolled in this study, and five of these patients were evaluated after testosterone treatment. Ten men with proven fertility were selected as a control group. An aliquot of seminal plasma from each individual was subjected to an in-solution digestion protocol and analyzed using an Ultimate 3000 RSLC-nano HPLC apparatus coupled to a LTQ Orbitrap Elite mass spectrometer. The label-free quantitative analysis was performed via Precursor Ions Area Detector Node. Eleven proteins were identified as decreased in hypogonadic patients versus controls, which are primarily included in hydrolase activity and protein binding activity. The comparison of the proteome before and after TRT comes about within the discovery of six increased proteins. This is the primary application of quantitative proteomics pointed to uncover a cluster of proteins reflecting an impairment not only of spermatogenesis but of the epididymal and prostate epithelial cell secretory function in male hypogonadism. The identified proteins might represent putative clinical markers valuable within the follow-up of patients with distinctive grades of male hypogonadism.

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A new methodical approach based on Compton scattering and XRF: quantitative analysis of CO2 and loss on ignition in quicklime

Powder Diffraction ◽

10.1017/s0885715615000275 ◽

2015 ◽

Vol 30 (2) ◽

pp. 113-116 ◽

Cited By ~ 1

Author(s):

Minoru Inoue ◽

Yasujiro Yamada ◽

Mao Kitamura ◽

Norifumi Gotoh ◽

Naoki Kawahara ◽

...

Keyword(s):

Quantitative Analysis ◽

High Reliability ◽

Background Characteristics ◽

Matrix Correction ◽

Loss On Ignition ◽

Calibration Equation ◽

Industrial Environment ◽

Sample Throughput ◽

Methodical Approach ◽

Before And After

The authors present and discuss a method for simultaneous quantitative analysis of total loss on ignition (LOI) (CO2 + H2O) and CO2 content separate from the LOI, in an industrial environment of quicklime production. Total LOI is determined by the Compton scattered RhKα tube radiation which is used directly in the calibration equation. The resulting calibration curve for LOI, including matrix correction shows an accuracy of 0.15 mass%. The carbon content (CO2) is distinguished from total LOI by measuring CKα radiation, which is possible with the required accuracy by employing a new multilayer analyzer with greatly improved background characteristics. The method aims at high reliability and sample throughput and at becoming a less time-consuming alternative to the conventional method of LOI determination by weighing sequences before and after “ignition” at 1050 °C.

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