750 research outputs found
Insect Diversity of the Lower Montane Evergreen Forest of the Western Andes Mountain Range: Cascada Chilicay and Suncamal
Biological research in the low montane evergreen forests of Ecuador focuses on ecological and botanical aspects, while knowledge of the entomofauna of these areas is almost nil. In February 2022, sampling was carried out during the dry season for 15 days, using direct and indirect capture methods (tapping, sieving, and light traps) in two waterfalls of the low montane evergreen forest of the western Andean Cordillera: Chilicay and Suncamal waterfalls, with the objective of identifying the composition of the terrestrial insect fauna at the family level. Two orders and 21 families were recorded, among which the families Carabidae and Noctuidae represented the highest percentage of the total abundance. Although preliminary, this work constitutes the first contribution to the knowledge of the entomofauna of this ecosystem.
Keywords: biodiversity, conservation, entomofauna, insects.
Resumen
Las investigaciones biológicas en los bosques siempreverdes montanos bajos de Ecuador, se centran en aspectos ecológicos y botánicos, mientras que el conocimiento de la entomofauna de estas zonas es escaso. En febrero de 2022, en la época seca y durante 15 días, utilizando métodos de captura directa e indirecta (golpeteo, tamizado y trampas de luz), se realizaron muestreos en dos cascadas del Bosque siempreverde montano bajo de la cordillera occidental de los Andes: Cascada Chilicay y Suncamal, con el objetivo de identificar la composición de la fauna de insectos terrestres a nivel de familia. Se registraron dos órdenes y 21 familias, entre las cuales, las familias Carabidae y Noctuidae representaron el mayor porcentaje de la abundancia total. Aunque en forma preliminar, este trabajo constituye el primer aporte al conocimiento de la entomofauna de este ecosistema.
Palabras Clave: Biodiversidad, conservación, entomofauna, insectos
HH 223: a parsec-scale H2 outflow in the star-forming region L723
The dark cloud Lynds 723 (L723) is a low-mass star-forming region where one
of the few known cases of a quadrupolar CO outflow has been reported. Two
recent works have found that the radio continuum source VLA 2, towards the
centre of the CO outflow, is actually a multiple system of young stellar
objects (YSOs). Several line-emission nebulae that lie projected on the
east-west CO outflow were detected in narrow-band Halpha and [SII] images. The
spectra of the knots are characteristic of shock-excited gas (Herbig-Haro
spectra), with supersonic blueshifted velocities, which suggests an optical
outflow also powered by the VLA 2 YSO system of L723. We imaged a field of ~5'
X 5' centred on HH 223, which includes the whole region of the quadrupolar CO
outflow with nir narrow-band filters . The H2 line-emission structures appear
distributed over a region of 5.5' (0.5 pc for a distance of 300 pc) at both
sides of the VLA 2 YSO system, with an S-shape morphology, and are projected
onto the east-west CO outflow. Most of them were resolved in smaller knotty
substructures. The [FeII] emission only appears associated with HH 223. An
additional nebular emission from the continuum in Hc and Kc appears associated
with HH 223-K1, the structure closest to the VLA 2 YSO system, and could be
tracing the cavity walls. We propose that the H2 structures form part of a
large-scale near-infrared outflow, which is also associated with the VLA 2 YSO
system. The current data do not allow us to discern which of the YSOs of VLA 2
is powering this large scale optical/near-infrared outflow.Comment: Accepted for A&A http://dx.doi.org/10.1051/0004-6361/201015125 12
pages, 9 figure
Integral Field Spectroscopy Of The Brightest Knots Of Hh 223 In L723
HH 223 is the optical counterpart of a larger scale H2 outflow, driven by the
protostellar source VLA 2A, in L723. Its poorly collimated and rather chaotic
morphology suggested the Integral Field Spectroscopy (IFS) as an appropriate
option to map the emission for deriving the physical conditions and the
kinematics. Here we present new results based on the IFS observations made with
the INTEGRAL system at the WHT. The brightest knots of HH 223 (\sim16 arcsec,
0.02 pc at a distance of 300 pc) were mapped with a single pointing in the
spectral range 6200-7700 A. We obtained the emission-line intensity maps for
Halpha, [NII] 6584 A and [SII] 6716, 6731 A, and explored the distribution of
the excitation and electron density from [NII]/Halpha, [SII]/Halpha, and [SII]
6716/6731 line-ratio maps. Maps of the radial velocity field were obtained. We
analysed the 3D-kinematics by combining the knot radial velocities, derived
from IFS data, with the knot proper motions derived from multi-epoch,
narrow-band images. The intensity maps built from IFS data reproduced well the
morphology found in the narrow-band images. We checked the results obtained
from previous long-slit observations with those derived from IFS spectra
extracted with a similar spatial sampling. At the positions intersected by the
slit, the physical conditions and kinematics derived from IFS are compatible
with those derived from long-slit data. In contrast, significant discrepancies
were found when the results from long-slit data were compared with the ones
derived from IFS spectra extracted at positions shifted a few arcsec from those
intersected by the slit. This clearly revealed IFS observations as the best
choice to get a reliable picture of the HH emission properties.Comment: 9 pages, 8 figures; Accepted for MNRA
Reproductive cycle of Solen marginatus (Pulteney, 1799) (Mollusca: Bivalvia) in the Eo and Villaviciosa rias (Asturias, northwestern Spain): Relationship with environmental parameters
Using histological analysis and condition indexes, the gametogenic cycle of Solen marginatus (Pulteney, 1799) in the Villaviciosa and Eo rias (Asturias, northwestern Spain) was determined. Environmental parameters (temperature, salinity, pH, O2 and chlorophyll a) were taken in both sampled areas. The reproductive cycle occurred later in the Eo than in the Villaciosa. In the Eo ria, spawning took place in July-August, whereas in the Villaviciosa ria it was observed in May-June. Analyses of the environmental parameters were carried out to examine the reasons for this behaviour, and significant differences in the concentration of chlorophyll a were found. The Villaviciosa ria is more productive, confirming that the availability of food has a direct relationship to the speed of gonadal development in S. marginatus.Se estudió el ciclo gametogénico de Solen marginatus (Pulteney, 1799) en las rías del Eo y Villaviciosa (Asturias, noroeste de España) usando análisis histológicos y el cálculo de índices de condición. El ciclo reproductivo en la ría del Eo presenta un retraso en comparación con el de la ría de Villaviciosa: el desove tuvo lugar en julio-agosto, mientras que en Villaviciosa tuvo lugar en mayo-junio. Se analizaron las variables ambientales, recogiendo datos sobre temperatura, salinidad, pH, O2 y clorofila a en ambas zonas del estudio, con el fin de explicar este desfase. Existen diferencias en la concentración de clorofila a. La ría de Villaviciosa es más productiva, confirmando que la disponibilidad de alimento guarda relación directa con la velocidad de desarrollo gonadal en S. marginatus.Instituto Español de Oceanografí
The nature of HH 223 from long-slit spectroscopy
HH 223 is a knotty, wiggling nebular emission of ~30" length found in the
L723 star-forming region. It lies projected onto the largest blueshifted lobe
of the cuadrupolar CO outflow powered by a low-mass YSO system embedded in the
core of L723. We analysed the physical conditions and kinematics along HH 223
with the aim of disentangling whether the emission arises from shock-excited,
supersonic gas characteristic of a stellar jet, or is only tracing the wall
cavity excavated by the CO outflow. We performed long-slit optical spectroscopy
along HH 223, crossing all the bright knots (A to E) and part of the
low-brightness emission nebula (F filament). One spectrum of each knot,
suitable to characterize the nature of its emission, was obtained. The physical
conditions and the radial velocity of the HH 223 emission along the slits were
also sampled at smaller scale (0.6") than the knot sizes. {The spectra of all
the HH 223 knots appear as those of the intermediate/high excitation
Herbig-Haro objects. The emission is supersonic, with blueshifted peak
velocities ranging from -60 to -130 km/s. Reliable variations in the kinematics
and physical conditions at smaller scale that the knot sizes are also found.
The properties of the HH 223 emission derived from the spectroscopy confirm the
HH nature of the object, the supersonic optical outflow most probably also
being powered by the YSOs embedded in the L723 core.Comment: A&A accepte
Direct visualization of the native structure of viroid RNAs at single-molecule resolution by atomic force microscopy
[EN] Viroids are small infectious, non-protein-coding circular RNAs that replicate independently and, in some cases, incite diseases in plants. They are classified into two families: Pospiviroidae, composed of species that have a central conserved region (CCR) and replicate in the cell nucleus, and Avsunviroidae, containing species that lack a CCR and whose multimeric replicative intermediates of either polarity generated in plastids self-cleave through hammerhead ribozymes. The compact, rod-like or branched, secondary structures of viroid RNAs have been predicted by RNA folding algorithms and further examined using different in vitro and in vivo experimental techniques. However, direct data about their native tertiary structure remain scarce. Here we have applied atomic force microscopy (AFM) to image at single-molecule resolution different variant RNAs of three representative viroids: potato spindle tuber viroid (PSTVd, family Pospiviroidae), peach latent mosaic viroid and eggplant latent viroid (PLMVd and ELVd, family Avsunviroidae). Our results provide a direct visualization of their native, three-dimensional conformations at 0 and 4 mM Mg2+ and highlight the role that some elements of tertiary structure play in their stabilization. The AFM images show that addition of 4 mM Mg2+ to the folding buffer results in a size contraction in PSTVd and ELVd, as well as in PLMVd when the kissing-loop interaction that stabilizes its 3D structure is preserved.This work was supported by the Spanish Ministerio de Economia y Competitividad (MINECO) grants BIO2016-79618-R (funded by EU under the FEDER programme) to C.B. and BFU2104-56812-P to R.F., as well as by the Comunidad de Madrid grant S2018/NMT-4349 to L.V. CIBERehd is funded by the Instituto de Salud Carlos III (ISCIII).Moreno, M.; Vázquez, L.; López Carrasco, A.; Martín-Gago, JA.; Flores Pedauye, R.; Briones, C. (2019). Direct visualization of the native structure of viroid RNAs at single-molecule resolution by atomic force microscopy. RNA Biology. 16(3):295-308. https://doi.org/10.1080/15476286.2019.1572436S295308163Diener, T. O. (2003). Discovering viroids — a personal perspective. Nature Reviews Microbiology, 1(1), 75-80. doi:10.1038/nrmicro736Flores, R., Hernández, C., Alba, A. E. M. de, Daròs, J.-A., & Serio, F. D. (2005). Viroids and Viroid-Host Interactions. Annual Review of Phytopathology, 43(1), 117-139. doi:10.1146/annurev.phyto.43.040204.140243Ding, B. (2009). The Biology of Viroid-Host Interactions. Annual Review of Phytopathology, 47(1), 105-131. doi:10.1146/annurev-phyto-080508-081927Zhang, Z., Qi, S., Tang, N., Zhang, X., Chen, S., Zhu, P., … Wu, Q. (2014). 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Annual Review of Microbiology, 68(1), 395-414. doi:10.1146/annurev-micro-091313-103416Diener, T. O. (1989). Circular RNAs: relics of precellular evolution? Proceedings of the National Academy of Sciences, 86(23), 9370-9374. doi:10.1073/pnas.86.23.9370Ruiz-Mirazo, K., Briones, C., & de la Escosura, A. (2013). Prebiotic Systems Chemistry: New Perspectives for the Origins of Life. Chemical Reviews, 114(1), 285-366. doi:10.1021/cr2004844Flores, R., Serra, P., Minoia, S., Di Serio, F., & Navarro, B. (2012). Viroids: From Genotype to Phenotype Just Relying on RNA Sequence and Structural Motifs. Frontiers in Microbiology, 3. doi:10.3389/fmicb.2012.00217Steger, G., & Perreault, J.-P. (2016). Structure and Associated Biological Functions of Viroids. Advances in Virus Research, 141-172. doi:10.1016/bs.aivir.2015.11.002Diener, T. O. (1972). Potato spindle tuber viroid. Virology, 50(2), 606-609. doi:10.1016/0042-6822(72)90412-6Gross, H. J., Domdey, H., Lossow, C., Jank, P., Raba, M., Alberty, H., & Sänger, H. L. (1978). Nucleotide sequence and secondary structure of potato spindle tuber viroid. Nature, 273(5659), 203-208. doi:10.1038/273203a0Gast, F.-U., Kempe, D., Spieker, R. L., & Sänger, H. L. (1996). Secondary Structure Probing of Potato Spindle Tuber Viroid (PSTVd) and Sequence Comparison with Other Small Pathogenic RNA Replicons Provides Evidence for Central Non-canonical Base-pairs, Large A-rich Loops, and a Terminal Branch. Journal of Molecular Biology, 262(5), 652-670. doi:10.1006/jmbi.1996.0543Giguère, T., Raj Adkar-Purushothama, C., & Perreault, J.-P. (2014). Comprehensive Secondary Structure Elucidation of Four Genera of the Family Pospiviroidae. PLoS ONE, 9(6), e98655. doi:10.1371/journal.pone.0098655López-Carrasco, A., & Flores, R. (2016). Dissecting the secondary structure of the circular RNA of a nuclear viroid in vivo: A «naked» rod-like conformation similar but not identical to that observed in vitro. RNA Biology, 14(8), 1046-1054. doi:10.1080/15476286.2016.1223005Wang, Y., Zirbel, C. L., Leontis, N. B., & Ding, B. (2018). RNA 3-dimensional structural motifs as a critical constraint of viroid RNA evolution. PLOS Pathogens, 14(2), e1006801. doi:10.1371/journal.ppat.1006801Zhong, X., Leontis, N., Qian, S., Itaya, A., Qi, Y., Boris-Lawrie, K., & Ding, B. (2006). Tertiary Structural and Functional Analyses of a Viroid RNA Motif by Isostericity Matrix and Mutagenesis Reveal Its Essential Role in Replication. Journal of Virology, 80(17), 8566-8581. doi:10.1128/jvi.00837-06Zhong, X., Tao, X., Stombaugh, J., Leontis, N., & Ding, B. (2007). Tertiary structure and function of an RNA motif required for plant vascular entry to initiate systemic trafficking. The EMBO Journal, 26(16), 3836-3846. doi:10.1038/sj.emboj.7601812Zhong, X., Archual, A. J., Amin, A. A., & Ding, B. (2008). A Genomic Map of Viroid RNA Motifs Critical for Replication and Systemic Trafficking. The Plant Cell, 20(1), 35-47. doi:10.1105/tpc.107.056606Hernandez, C., & Flores, R. (1992). Plus and minus RNAs of peach latent mosaic viroid self-cleave in vitro via hammerhead structures. Proceedings of the National Academy of Sciences, 89(9), 3711-3715. doi:10.1073/pnas.89.9.3711Fadda, Z., Daròs, J. A., Fagoaga, C., Flores, R., & Duran-Vila, N. (2003). Eggplant Latent Viroid
, the Candidate Type Species for a New Genus within the Family
Avsunviroidae
(Hammerhead Viroids). Journal of Virology, 77(11), 6528-6532. doi:10.1128/jvi.77.11.6528-6532.2003Navarro, B., & Flores, R. (1997). Chrysanthemum chlorotic mottle viroid: Unusual structural properties of a subgroup of self-cleaving viroids with hammerhead ribozymes. Proceedings of the National Academy of Sciences, 94(21), 11262-11267. doi:10.1073/pnas.94.21.11262Bussière, F., Ouellet, J., Côté, F., Lévesque, D., & Perreault, J. P. (2000). Mapping in Solution Shows the Peach Latent Mosaic Viroid To Possess a New Pseudoknot in a Complex, Branched Secondary Structure. Journal of Virology, 74(6), 2647-2654. doi:10.1128/jvi.74.6.2647-2654.2000GAGO, S. (2005). A kissing-loop interaction in a hammerhead viroid RNA critical for its in vitro folding and in vivo viability. RNA, 11(7), 1073-1083. doi:10.1261/rna.2230605Dube, A., Baumstark, T., Bisaillon, M., & Perreault, J.-P. (2010). The RNA strands of the plus and minus polarities of peach latent mosaic viroid fold into different structures. RNA, 16(3), 463-473. doi:10.1261/rna.1826710Sogo, J. M., Koller, T., & Diener, T. O. (1973). Potato spindle tuber viroid. Virology, 55(1), 70-80. doi:10.1016/s0042-6822(73)81009-8Goodman, T. C., Nagel, L., Rappold, W., Klotz, G., & Riesner, D. (1984). Viroid replication: equilibrium association constant and comparative activity measurements for the viroid-polymerase interaction. Nucleic Acids Research, 12(15), 6231-6246. doi:10.1093/nar/12.15.6231Sanger, H. L., Klotz, G., Riesner, D., Gross, H. J., & Kleinschmidt, A. K. (1976). Viroids are single-stranded covalently closed circular RNA molecules existing as highly base-paired rod-like structures. Proceedings of the National Academy of Sciences, 73(11), 3852-3856. doi:10.1073/pnas.73.11.3852McClements, W. L., & Kaesberg, P. (1977). Size and secondary structure of potato spindle tuber viroid. Virology, 76(2), 477-484. doi:10.1016/0042-6822(77)90230-6Bustamante, C., & Keller, D. (1995). Scanning Force Microscopy in Biology. Physics Today, 48(12), 32-38. doi:10.1063/1.881478Hansma, H. G., Kasuya, K., & Oroudjev, E. (2004). Atomic force microscopy imaging and pulling of nucleic acids. Current Opinion in Structural Biology, 14(3), 380-385. doi:10.1016/j.sbi.2004.05.005Kuznetsov, Y. G., Daijogo, S., Zhou, J., Semler, B. L., & McPherson, A. (2005). Atomic Force Microscopy Analysis of Icosahedral Virus RNA. Journal of Molecular Biology, 347(1), 41-52. doi:10.1016/j.jmb.2005.01.006Alvarez, D. E., Lodeiro, M. F., Ludueña, S. J., Pietrasanta, L. I., & Gamarnik, A. V. (2005). Long-Range RNA-RNA Interactions Circularize the Dengue Virus Genome. Journal of Virology, 79(11), 6631-6643. doi:10.1128/jvi.79.11.6631-6643.200
Sensitive quantification of the HIV-1 reservoir in gut-associated lymphoid tissue
Biòpsia; VIH-1; Teixit limfoideBiopsia; VIH-1; Tejido linfoideBiopsy; HIV-1; Lymphoid tissueBackground
The implementation of successful strategies to achieve an HIV cure has become a priority in HIV research. However, the current location and size of HIV reservoirs is still unknown since there are limited tools to evaluate HIV latency in viral sanctuaries such as gut-associated lymphoid tissue (GALT). As reported in the so called “Boston Patients”, despite undetectable levels of proviral HIV-1 DNA in blood and GALT, viral rebound happens in just few months after ART interruption. This fact might imply that current methods are not sensitive enough to detect residual reservoirs. Showing that, it is imperative to improve the detection and quantification of HIV-1 reservoir in tissue samples. Herein, we propose a novel non-enzymatic protocol for purification of Lamina Propria Leukocytes (LPL) from gut biopsies combined to viral HIV DNA (vDNA) quantification by droplet digital PCR (ddPCR) to improve the sensitivity and accuracy of viral reservoir measurements (LPL-vDNA assay).
Methods
Endoscopic ileum biopsies were sampled from 12 HIV-1-infected cART-suppressed subjects. We performed a DTT/EDTA-based treatment for epithelial layer removal followed by non-enzymatic disruption of the tissue to obtain lamina propria cell suspension (LP). CD45+ cells were subsequently purified by flow sorting and vDNA was determined by ddPCR.
Results
vDNA quantification levels were significantly higher in purified LPLs (CD45+) than in bulk LPs (p<0.01). The levels of vDNA were higher in ileum samples than in concurrent PBMC from the same individuals (p = 0.002). As a result of the increased sensitivity of this purification method, the Poisson 95% confidence intervals of the vDNA quantification data from LPLs were narrower than that from bulk LPs. Of note, vDNA was unambiguously quantified above the detection limit in 100% of LPL samples, while only in 58% of bulk LPs.
Conclusion
We propose an innovative combined protocol for a more sensitive detection of the HIV reservoir in gut-associated viral sanctuaries, which might be used to evaluate any proposed eradication strategy.This substudy was supported by ViiV and the American Foundation for AIDS Research (amfAR) (ARCHE). IrsiCaixa was supported by the CERCA programme from Generalitat de Catalunya. MS was supported by the post-doctoral training scholarship (Juan de la Cierva) of the Spanish Economy and Competitiveness Ministry (FPDI-2013-17134). SM-L received a fellowship from the Agència de Gestió d’Ajuts Universitaris i de Recerca (2013FI_B 00275). CG was partially supported by the pre-doctoral fellowship of the Spanish Education, Culture and Sport Ministry (FPU15/03698). The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication
Evaluation of bone mineral with dexa in youth soccer players
El objetivo de este estudio fue evaluar la densidad mineral ósea (DMO) y el contenido mineral óseo (CMO) de los segmentos corporales durante un periodo de entrenamiento de seis meses. Se evaluaron a 41 futbolistas juveniles profesionales en dos momentos, una al comienzo (TI) y otra al final (TF) de la intervención con el equipo de absorciometría dual de rayos X (DEXA). Se lograron aumentos significativos en la DMO en los segmentos corporales de la cadera, columna lumbar, triangulo de Ward, tronco y del cuerpo total (p<0.05). También se obtuvo un incremento significativo del CMO en la cadera, columna lumbar, pierna, tronco y costillas (p<0.05). El entrenamiento de futbol fortaleció el CMO y la DMO del hueso de la extremidad inferior y de la caja torácica, con lo cual el fútbol podría ser una actividad útil para la mejorar la mineralización y fortalecimiento del hueso, para prevenir lesiones y fracturasThe objective of this study was to assess bone mineral density (BMD) and bone mineral content (BMC) of body segments for a six months training period. 41 professional youth players were evaluated in two moments, one at the beginning (TI) and another at the end (TF) of the intervention with the dual energy x-ray absorptiometry equipment (DEXA). Significant increases in BMD were achieved in the body segments of the hip, lumbar spine, ward triangle, trunk and total body (p <0.05). There was also a significant increase in BMC in the hip, lumbar spine, leg, trunk and ribs (p <0.05). Soccer training strengthened the BMC and BMD of the lower limb bone and the rib cage, which could be a useful activity to improve bone mineralization and strengthening, to prevent injuries and fracture
Relevant Design Aspects to Improve the Stability of Titanium Dental Implants
Post-extractional implants and immediate loading protocols are becoming much more
frequent in everyday clinical practice. Given the existing literature about tapered implants, the
objective of this paper was to understand whether implant shape had a direct influence on the
results of the insertion torque (IT) and implant stability quotient (ISQ). Seven tapered implant
prototypes were developed and distributed into three groups and compared with a control cylindrical
implant—VEGA by Klockner Implant System. The implants were inserted into bovine bone type III
according to Lekholm and Zarb Classification. The sample size was n = 30 for the three groups. Final
IT was measured with a torquemeter, and the ISQ was measured with Penguin Resonance Frequency
Analysis (RFA). Modifications done to the Prototype I did not reveal higher values of the ISQ and IT
when compared to VEGA. In the second group, when comparing the five prototypes (II–VI) with
VEGA, it was seen that the values of the ISQ and IT were not always higher, but there were two
values of the ISQ that were statistically significantly higher with the 4.0 mm diameter Prototypes II
(76.3 ± 6.1) and IV (78 ± 3.7). Prototype VII was the one with higher and significant values of the ISQ
and IT. In both diameters and in both variables, all differences were statistically significant enough
to achieve the higher values of primary stability values (IT and ISQ). Given the limitations of this
study, it can be concluded that when there is an increase of the diameter of the implant and body
taper, there is an increase of the ISQ and IT, showing that the diameter of the implant is an important
criteria to obtain higher values of primary stability
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