4,039 research outputs found
Treehoppers (Hemiptera: Aetalionidae and Membracidae) from Madre de Dios region, Peru
A list of treehoppers (Aetalionidae and Membracidae) is presented from Madre de Dios region at the southeastern Amazon basin in Peru. The treehopper specimens were collected as by-catch in a survey of the beetles in the Villa Carmen Biological Station and Los Amigos Biological Station. The list comprises 44 species, 31 genera, 16 tribes and 9 subfamilies. Ten genera are new records to Peru. The images of representative specimens of each identified species and genera are provided to facilitate the identification of the local treehopper fauna.
Resumen: Se presenta una lista de los membrácidos (Aetalionidae y Membracidae) de la regiĂłn Madre de Dios, en el sureste de la cuenca AmazĂłnica, en PerĂş. La lista está basada en especĂmenes recolectados como captura fortuita en un inventario de escarabajos en las estaciones biolĂłgicas Villa Carmen y Los Amigos. La lista incluye 44 especies, 31 gĂ©neros, 16 tribus y 9 subfamilias. Diez gĂ©neros son nuevos registros para PerĂş. Se presentan las imágenes de especĂmenes representativos de cada especie y gĂ©nero para facilitar la identificiĂłn de la fauna local de los membrácidos
Membrácidos (Hemiptera: Aetalionidae y Membracidae) de la región de Madre de Dios, Perú
A list of treehoppers (Aetalionidae and Membracidae) is presented from Madre de Dios region at the southeastern Amazon basin in Peru. The treehopper specimens were collected as by-catch in a survey of the beetles in the Villa Carmen Biological Station and Los Amigos Biological Station. The list comprises 44 species, 31 genera, 16 tribes and 9 subfamilies. Ten genera are new records to Peru. The images of representative specimens of each identified species and genera are provided to facilitate the identification of the local treehopper fauna.Se presenta una lista de los membrácidos (Aetalionidae y Membracidae) de la regiĂłn Madre de Dios, en el sureste de la cuenca AmazĂłnica, en PerĂş. La lista está basada en especĂmenes recolectados como captura fortuita en un inventario de escarabajos en las estaciones biolĂłgicas Villa Carmen y Los Amigos. La lista incluye 44 especies, 31 gĂ©neros, 16 tribus y 9 subfamilias. Diez gĂ©neros son nuevos registros para PerĂş. Se presentan las imágenes de especĂmenes representativos de cada especie y gĂ©nero para facilitar la identificiĂłn de la fauna local de los membrácidos
Ludwigia octovalvis extract improves glycemic control and memory performance in diabetic mice
Ethnopharmacological relevance
Ludwigia octovalvis (Jacq.) P.H. Raven (Onagraceae) extracts have historically been consumed as a healthful drink for treating various conditions, including edema, nephritis, hypotension and diabetes.
Aim of the study
We have previously shown that Ludwigia octovalvis extract (LOE) can significantly extend lifespan and improve age-related memory deficits in Drosophila melanogaster through activating AMP-activated protein kinase (AMPK). Since AMPK has become a critical target for treating diabetes, we herein investigate the anti-hyperglycemic potential of LOE.
Materials and methods
Differentiated C2C12 muscle cells, HepG2 hepatocellular cells, streptozotocin (STZ)-induced diabetic mice and high fat diet (HFD)-induced diabetic mice were used to investigate the anti-hyperglycemic potential of LOE. The open field test and novel object recognition test were used to evaluate spontaneous motor activity and memory performance of HFD-induced diabetic mice.
Results
In differentiated C2C12 muscle cells and HepG2 hepatocellular cells, treatments with LOE and its active component (β-sitosterol) induced significant AMPK phosphorylation. LOE also enhanced uptake of a fluorescent glucose derivative (2-NBDG) and inhibited glucose production in these cells. The beneficial effects of LOE were completely abolished when an AMPK inhibitor, dorsomorphin, was added to the culture system, suggesting that LOE requires AMPK activation for its action in vitro. In streptozotocin (STZ)-induced diabetic mice, we found that both LOE and β-sitosterol induced an anti-hyperglycemic effect comparable to that of metformin, a drug that is commonly prescribed to treat diabetes. Moreover, LOE also improved glycemic control and memory performance of mice fed a HFD.
Conclusions
These results indicate that LOE is a potent anti-diabetic intervention that may have potential for future clinical applications
The site conditions of the Guo Shou Jing Telescope
The weather at Xinglong Observing Station, where the Guo Shou Jing Telescope
(GSJT) is located, is strongly affected by the monsoon climate in north-east
China. The LAMOST survey strategy is constrained by these weather patterns. In
this paper, we present a statistics on observing hours from 2004 to 2007, and
the sky brightness, seeing, and sky transparency from 1995 to 2011 at the site.
We investigate effects of the site conditions on the survey plan. Operable
hours each month shows strong correlation with season: on average there are 8
operable hours per night available in December, but only 1-2 hours in July and
August. The seeing and the sky transparency also vary with seasons. Although
the seeing is worse in windy winters, and the atmospheric extinction is worse
in the spring and summer, the site is adequate for the proposed scientific
program of LAMOST survey. With a Monte Carlo simulation using historical data
on the site condition, we find that the available observation hours constrain
the survey footprint from 22h to 16h in right ascension; the sky brightness
allows LAMOST to obtain the limit magnitude of V = 19.5mag with S/N = 10.Comment: 10 pages, 8 figures, accepted for publication in RA
Current and state of the art on the electrophysiologic characteristics and catheter ablation of arrhythmogenic right ventricular dysplasia/cardiomyopathy
AbstractArrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is an inherited genetic disease caused by defective desmosomal proteins, and it has typical histopathological features characterized by predominantly progressive fibro-fatty infiltration of the right ventricle. Clinical presentations of ARVD/C vary from syncope, progressive heart failure (HF), ventricular tachyarrhythmias, and sudden cardiac death (SCD). The 2010 modified Task Force criteria were established to facilitate the recognition and diagnosis of ARVD/C. An implantable cardiac defibrillator (ICD) remains to be the cornerstone in prevention of SCD in patients fulfilling the diagnosis of definite ARVD/C, especially among ARVD/C patients with syncope, hemodynamically unstable ventricular tachycardia (VT), ventricular fibrillation, and aborted SCD. Further risk stratification is clinically valuable in the management of patients with borderline or possible ARVD/C and mutation carriers of family members. However, given the entity of heterogeneous penetrance and non-uniform phenotypes, the standardization of clinical practice guidelines for at-risk individuals will be the next frontier to breakthrough.Antiarrhythmic drugs are prescribed frequently to patients experiencing frequent ventricular tachyarrhythmias and/or appropriate ICD shocks. Amiodarone is the recommended drug of choice. Radiofrequency catheter ablation (RFCA) has been demonstrated to effectively eliminate the drug-refractory VT in patients with ARVD/C. However, the efficacy and clinical prognosis of RFCA via endocardial approach alone was disappointing prior to the era of epicardial approach. In recent years, it has been proven that the integration of endocardial and epicardial ablation by targeting the critical isthmus or eliminating abnormal electrograms within the diseased substrates could yield higher acute success and lower recurrence of ventricular tachyarrhythmias during long-term follow-up. Heart transplantation is the final option for patients with extensive disease, biventricular HF with uncontrollable hemodynamic compromise, and refractory ventricular tachyarrhythmias despite aggressive medical and ablation therapies
The LEGUE Input Catalogue for Dark Night Observing in the LAMOST Pilot Survey
We outline the design of the dark nights portion of the LAMOST Pilot Survey,
which began observations in October 2011. In particular, we focus on Milky Way
stellar candidates that are targeted for the LEGUE (LAMOST Experiment for
Galactic Understanding and Exploration) survey. We discuss the regions of sky
in which spectroscopic candidates were selected, and the motivations for
selecting each of these sky areas. Some limitations due to the unique design of
the telescope are discussed, including the requirement that a bright (V < 8)
star be placed at the center of each plate for wavefront sensing and active
optics corrections. The target selection categories and scientific goals
motivating them are briefly discussed, followed by a detailed overview of how
these selection functions were realized. We illustrate the difference between
the overall input catalog - Sloan Digital Sky Survey (SDSS) photometry - and
the final targets selected for LAMOST observation.Comment: 11 pages, 7 figures, accepted for publication in RA
Electrochemical behavior of near-beta titanium biomedical alloys in phosphate buffer saline solution
The electrochemical behavior of three different near-β titanium alloys (composed by Ti, Nb and Sn) obtained by powder metallurgy for biomedical applications has been investigated. Different electrochemical and microscopy techniques were used to study the influence of the chemical composition (Sn content) and the applied potential on themicrostructure and the corrosion mechanisms of those titaniumalloys. The addition of Sn below4wt.% to the titanium powder improves the microstructural homogeneity and generates an alloy with high corrosion resistancewith
lowelasticmodulus, beingmore suitable as a biomaterial.When the Sn content is above 4%, the corrosion resistance considerably decreases by increasing the passive dissolution rate; this effect is enhanced with the applied potential.The authors would like to thank the Ministerio de Ciencia e Innovacion of the Spanish Government for the financial support under the project MAT2011-22481.Dalmau Borrás, A.; Guiñón Pina, V.; Devesa Albeza, F.; Amigó Borrás, V.; Igual Muñoz, AN. (2015). Electrochemical behavior of near-beta titanium biomedical alloys in phosphate buffer saline solution. Materials Science and Engineering: C. 48:55-62. https://doi.org/10.1016/j.msec.2014.11.036S55624
(electronic) Mitochondrial DNA, Early Online: 1-2 !
Abstract This study reported the 15,435 bp-long complete mitochondrial genome of the relict Epiophlebia superstes (Odonata, Epiophlebiidae), an enigmatic dragonfly of the paraphyletic 'Anisozygoptera' possessing characteristics similar to members of both extant odonate suborders, the Zygoptera and the Anisoptera. This mitogenome comprises the common set of 37 genes and an A Ăľ T-rich control region, and has a gene arrangement identical to those of all available odonates. The genome contains three non-coding inter-genic spacers (s1-s3), which occurs in all of other known odonates, but it lacks the inter-genic spacer s5 typically found in the Anisoptera. This result suggests that E. superstes possesses a mitogenmic organization more closely related to that of the Zygoptera than that of the Anizoptera
Cell arrest and cell death in mammalian preimplantation development
The causes, modes, biological role and prospective significance of cell death in preimplantation development in humans and other mammals are still poorly understood. Early bovine embryos represent a very attractive experimental model for the investigation of this fundamental and important issue.
To obtain reference data on the temporal and spatial occurrence of cell death in early bovine embryogenesis, three-dimensionally preserved embryos of different ages and stages of development up to hatched blastocysts were examined in toto by confocal laser scanning microscopy. In parallel, transcript abundance profiles for selected apoptosis-related genes were analyzed by real-time reverse transcriptase-polymerase chain reaction. Our study documents that in vitro as well as in vivo, the first four cleavage cycles are prone to a high failure rate including different types of permanent cell cycle arrest and subsequent non-apoptotic blastomere death. In vitro produced and in vivo derived blastocysts showed a significant incidence of cell death in the inner cell mass (ICM), but only in part with morphological features of apoptosis. Importantly, transcripts for CASP3, CASP9, CASP8 and FAS/FASLG were not detectable or found at very low abundances.
In vitro and in vivo, errors and failures of the first and the next three cleavage divisions frequently cause immediate embryo death or lead to aberrant subsequent development, and are the main source of developmental heterogeneity. A substantial occurrence of cell death in the ICM even in fast developing blastocysts strongly suggests a regular developmentally controlled elimination of cells, while the nature and mechanisms of ICM cell death are unclear. Morphological findings as well as transcript levels measured for important apoptosis-related genes are in conflict with the view that classical caspase-mediated apoptosis is the major cause of cell death in early bovine development
An Algorithm for Preferential Selection of Spectroscopic Targets in LEGUE
We describe a general target selection algorithm that is applicable to any
survey in which the number of available candidates is much larger than the
number of objects to be observed. This routine aims to achieve a balance
between a smoothly-varying, well-understood selection function and the desire
to preferentially select certain types of targets. Some target-selection
examples are shown that illustrate different possibilities of emphasis
functions. Although it is generally applicable, the algorithm was developed
specifically for the LAMOST Experiment for Galactic Understanding and
Exploration (LEGUE) survey that will be carried out using the Chinese Guo Shou
Jing Telescope. In particular, this algorithm was designed for the portion of
LEGUE targeting the Galactic halo, in which we attempt to balance a variety of
science goals that require stars at fainter magnitudes than can be completely
sampled by LAMOST. This algorithm has been implemented for the halo portion of
the LAMOST pilot survey, which began in October 2011.Comment: 17 pages, 7 figures, accepted for publication in RA
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