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1.
An Acad Bras Cienc ; 91(2): e20180291, 2019.
Article in English | MEDLINE | ID: mdl-31038535

ABSTRACT

We report for the first time Aphanistes ruthae Alvarado, 2018 in Venezuela and Castrosion renei Gauld & Bradshaw, 1997 in South America (Venezuela and Brazil). Castrosion renei is associated with the amazon rainforest in the Amazonas and Maranhão, States of Brazil.


Subject(s)
Hymenoptera/anatomy & histology , Animal Distribution , Animals , Brazil , Costa Rica , Female , Hymenoptera/physiology , Male , Rainforest , Species Specificity , Venezuela
2.
Sensors (Basel) ; 18(9)2018 Sep 17.
Article in English | MEDLINE | ID: mdl-30227618

ABSTRACT

Three-dimensional digital image correlation (3D-DIC) has become the most popular full-field optical technique for measuring 3D shapes and displacements in experimental mechanics. The integration of fringe projection (FP) and two-dimensional digital image correlation (FP + DIC) has been recently established as an intelligent low-cost alternative to 3D-DIC, overcoming the drawbacks of a stereoscopic system. Its experimentation is based on the colour encoding of the characterized fringe and speckle patterns required for FP and DIC implementation, respectively. In the present work, innovations in experimentation using FP + DIC for more accurate results are presented. Specifically, they are based on the improvement of the colour pattern encoding. To achieve this, in this work, a multisensor camera and/or laser structural illumination were employed. Both alternatives are analysed and evaluated. Results show that improvements both in three-dimensional and in-plane displacement are obtained with the proposed alternatives. Nonetheless, multisensor high-speed cameras are uncommon, and laser structural illumination is established as an important improvement when low uncertainty is required for 2D-displacement measurement. Hence, the uncertainty has been demonstrated to be reduced by up to 50% compared with results obtained in previous experimental approaches of FP + DIC.

3.
Insects ; 9(2)2018 Apr 20.
Article in English | MEDLINE | ID: mdl-29677153

ABSTRACT

Agroforestry systems are environment-friendly production systems which help to preserve biodiversity while providing people with a way of earning a living. Cacao is a historically important crop in Venezuela that traditionally has been produced in agroforestry systems. However, few studies have evaluated how different trees used in those systems affect the dynamics and abundance of insects. The present study evaluated the entomofauna assemblages associated with different combinations of four timber-yielding trees and four Criollo cacao cultivars established in a lowland tropical ecosystem in Venezuela. A randomized block design with two replicates was used, each block having 16 plots which included all 16 possible combinations of four native timber trees (Cordia thaisiana, Cedrela odorata, Swietenia macrophylla, and Tabebuia rosea) and four Criollo cacao cultivars (Porcelana, Guasare, Lobatera and Criollo Merideño). Insects were collected with yellow pan traps and sorted to order. Coleoptera and parasitoid Hymenoptera were determined to the family level. In total, 49,538 individuals of seven orders were collected, with Hymenoptera, Diptera, and Hemiptera being the most abundant, although only Lepidoptera and Coleoptera abundances were significantly influenced by the timber tree species. Twenty-three families of parasitoid Hymenoptera and 26 of Coleoptera were found. Significant differences in insects’ assemblages were found both in parasitoid Hymenoptera and Coleoptera families associated to every shade tree, with the families Eulophidae and Lycidae being indicators for Cordia, and Chalcididae for Swietenia. The entomofauna relationship with the cacao cultivar was barely significant, although Scydmaenidae and Scarabaeidae were indicators for Lobatera and Merideño, respectively. No significant effects were found for interaction with cacao cultivars and native trees. We concluded that the particular insect assemblages found in Cedrela odorata and Cordia thaisiana, together with their high growing rates, make these two species an optimal choice for cacao agroforestry systems.

4.
Materials (Basel) ; 11(2)2018 Feb 02.
Article in English | MEDLINE | ID: mdl-29393897

ABSTRACT

In real aircraft structures the comfort and the occupational performance of crewmembers and passengers are affected by the presence of noise. In this sense, special attention is focused on mechanical and material design for isolation and vibration control. Experimental characterization and, in particular, experimental modal analysis, provides information for adequate cabin noise control. Traditional sensors employed in the aircraft industry for this purpose are invasive and provide a low spatial resolution. This paper presents a methodology for experimental modal characterization of a front fuselage full-scale demonstrator using high-speed 3D digital image correlation, which is non-invasive, ensuring that the structural response is unperturbed by the instrumentation mass. Specifically, full-field measurements on the passenger window area were conducted when the structure was excited using an electrodynamic shaker. The spectral analysis of the measured time-domain displacements made it possible to identify natural frequencies and full-field operational deflection shapes. Changes in the modal parameters due to cabin pressurization and the behavior of different local structural modifications were assessed using this methodology. The proposed full-field methodology allowed the characterization of relevant dynamic response patterns, complementing the capabilities provided by accelerometers.

5.
Materials (Basel) ; 11(2)2018 Feb 05.
Article in English | MEDLINE | ID: mdl-29401725

ABSTRACT

The modal characterization of automotive lighting systems becomes difficult using sensors due to the light weight of the elements which compose the component as well as the intricate access to allocate them. In experimental modal analysis, high speed 3D digital image correlation (HS 3D-DIC) is attracting the attention since it provides full-field contactless measurements of 3D displacements as main advantage over other techniques. Different methodologies have been published that perform modal identification, i.e., natural frequencies, damping ratios, and mode shapes using the full-field information. In this work, experimental modal analysis has been performed in a multi-component automotive lighting system using HS 3D-DIC. Base motion excitation was applied to simulate operating conditions. A recently validated methodology has been employed for modal identification using transmissibility functions, i.e., the transfer functions from base motion tests. Results make it possible to identify local and global behavior of the different elements of injected polymeric and metallic materials.

6.
Materials (Basel) ; 10(7)2017 Jun 28.
Article in English | MEDLINE | ID: mdl-28773081

ABSTRACT

A quasistatic indentation numerical analysis in a round section specimen made of soft material has been performed and validated with a full field experimental technique, i.e., Digital Image Correlation 3D. The contact experiment specifically consisted of loading a 25 mm diameter rubber cylinder of up to a 5 mm indentation and then unloading. Experimental strains fields measured at the surface of the specimen during the experiment were compared with those obtained by performing two numerical analyses employing two different hyperplastic material models. The comparison was performed using an Image Decomposition new methodology that makes a direct comparison of full-field data independently of their scale or orientation possible. Numerical results show a good level of agreement with those measured during the experiments. However, since image decomposition allows for the differences to be quantified, it was observed that one of the adopted material models reproduces lower differences compared to experimental results.

7.
Zootaxa ; 3795: 193-7, 2014 May 12.
Article in English | MEDLINE | ID: mdl-24870473

ABSTRACT

The subfamily Poemeniinae (Hymenoptera, Ichneumonidae) is reported for the first time from Peru. We describe and illustrate a new species, Ganodes atayupanquii sp. n. Castillo & Sääksjärvi, which was collected from the Peruvian Andes at 1500 m. A key to the species of Ganodes Townes and new distribution records of G. wahli Díaz and G. matai Gauld are provided.


Subject(s)
Biodiversity , Wasps/classification , Animals , Female , Peru , Wasps/anatomy & histology
8.
Neotrop. entomol ; 37(6): 668-673, Nov.-Dec. 2008. ilus
Article in English | LILACS | ID: lil-507023

ABSTRACT

Five new species of the Neotropical genus Ganodes Townes, from Mexico, Venezuela, Brazil and Argentina, are described and illustrated: G. bocaina, G. garciai, G. mexicanus, G. townesi and. G. wahli. A key to seven species is provided, including two species described previously, G. balteatus Townes and G. matai Gauld.


Cinco espécies do gênero Neotropical Ganodes Townes, coletadas no México, Venezuela, Brasil e Argentina, são descritas e ilustradas: G. bocaina, G. garciai, G. mexicanus, G. townesi y G. wahli. É apresentada uma chave para sete espécies, incluindo duas descritas anteriormente, G. balteatus Townes e G. matai Gauld.


Subject(s)
Animals , Hymenoptera/classification , Argentina , Brazil , Hymenoptera/anatomy & histology , Mexico , Venezuela
9.
Neotrop Entomol ; 37(6): 668-73, 2008.
Article in English | MEDLINE | ID: mdl-19169554

ABSTRACT

Five new species of the Neotropical genus Ganodes Townes, from Mexico, Venezuela, Brazil and Argentina, are described and illustrated: G. bocaina, G. garciai, G. mexicanus, G. townesi and. G. wahli. A key to seven species is provided, including two species described previously, G. balteatus Townes and G. matai Gauld.


Subject(s)
Hymenoptera/classification , Animals , Argentina , Brazil , Hymenoptera/anatomy & histology , Mexico , Venezuela
10.
J Public Health Manag Pract ; 13(3): 252-62, 2007.
Article in English | MEDLINE | ID: mdl-17435492

ABSTRACT

BACKGROUND: We aimed to increase human immunodeficiency virus (HIV) counseling, testing, referral (CTR), and knowledge of HIV serostatus of close contacts of tuberculosis patients and improve tuberculosis screening and treatment of HIV-infected contacts. METHODS: Of close contacts to infectious tuberculosis patients reported from December 2002 to November 2003, investigators (1) offered HIV CTR, (2) identified factors associated with HIV testing, and (3) assessed study costs. RESULTS: Of 614 contacts, 569 (93%) were provided HIV information and offered HIV CTR. Of the 569, 58 (10%) were previously HIV tested; 165 (29%) were newly HIV tested; and 346 (61%) were not tested. None of the 165 newly HIV tested contacts were HIV infected. Contacts more likely to be newly HIV tested (vs not tested) included those aged 18-24, Hispanic, or non-Hispanic Black. Of 24 HIV-infected contacts, 71 percent received chest-radiograph screening for tuberculosis disease; 56 percent of 18 eligible for latent-tuberculosis-infection treatment started and half completed. It cost $1 per patient to provide HIV information and $5-$8 to offer HIV CTR. CONCLUSION: The project increased HIV CTR of close contacts of infectious tuberculosis patients. The important factor for success in knowing contacts' HIV serostatus was simply for TB program staff to ask about it and offer the test to those who did not know their status.


Subject(s)
AIDS Serodiagnosis/statistics & numerical data , AIDS-Related Opportunistic Infections/prevention & control , Contact Tracing/methods , Counseling/statistics & numerical data , HIV Infections/diagnosis , Public Health Administration/methods , Tuberculosis, Pulmonary/prevention & control , AIDS Serodiagnosis/economics , AIDS-Related Opportunistic Infections/epidemiology , Adolescent , Adult , Contact Tracing/economics , Cost-Benefit Analysis , Counseling/economics , Disease Notification/economics , Feasibility Studies , Female , HIV Infections/complications , Health Knowledge, Attitudes, Practice , Humans , Male , Middle Aged , New York City/epidemiology , Outcome and Process Assessment, Health Care , Public Health Administration/economics , Radiography, Thoracic/statistics & numerical data , Referral and Consultation/economics , Referral and Consultation/statistics & numerical data , Socioeconomic Factors , Tuberculosis, Pulmonary/complications , Tuberculosis, Pulmonary/epidemiology
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