29 research outputs found
280 one-opposition near-Earth asteroids recovered by the EURONEAR with the <i>Isaac Newton</i> Telescope
Context. One-opposition near-Earth asteroids (NEAs) are growing in number, and they must be recovered to prevent loss and mismatch risk, and to improve their orbits, as they are likely to be too faint for detection in shallow surveys at future apparitions.
Aims. We aimed to recover more than half of the one-opposition NEAs recommended for observations by the Minor Planet Center (MPC) using the Isaac Newton Telescope (INT) in soft-override mode and some fractions of available D-nights. During about 130 h in total between 2013 and 2016, we targeted 368 NEAs, among which 56 potentially hazardous asteroids (PHAs), observing 437 INT Wide Field Camera (WFC) fields and recovering 280 NEAs (76% of all targets).
Methods. Engaging a core team of about ten students and amateurs, we used the THELI, Astrometrica, and the Find_Orb software to identify all moving objects using the blink and track-and-stack method for the faintest targets and plotting the positional uncertainty ellipse from NEODyS.
Results. Most targets and recovered objects had apparent magnitudes centered around V ~ 22.8 mag, with some becoming as faint as V ~ 24 mag. One hundred and three objects (representing 28% of all targets) were recovered by EURONEAR alone by Aug. 2017. Orbital arcs were prolonged typically from a few weeks to a few years; our oldest recoveries reach 16 years. The O−C residuals for our 1854 NEA astrometric positions show that most measurements cluster closely around the origin. In addition to the recovered NEAs, 22 000 positions of about 3500 known minor planets and another 10 000 observations of about 1500 unknown objects (mostly main-belt objects) were promptly reported to the MPC by our team. Four new NEAs were discovered serendipitously in the analyzed fields and were promptly secured with the INT and other telescopes, while two more NEAs were lost due to extremely fast motion and lack of rapid follow-up time. They increase the counting to nine NEAs discovered by the EURONEAR in 2014 and 2015.
Conclusions. Targeted projects to recover one-opposition NEAs are efficient in override access, especially using at least two-meter class and preferably larger field telescopes located in good sites, which appear even more efficient than the existing surveys
RNAseq Analyses Identify Tumor Necrosis Factor-Mediated Inflammation as a Major Abnormality in ALS Spinal Cord
ALS is a rapidly progressive, devastating neurodegenerative illness of adults that produces disabling weakness and spasticity arising from death of lower and upper motor neurons. No meaningful therapies exist to slow ALS progression, and molecular insights into pathogenesis and progression are sorely needed. In that context, we used high-depth, next generation RNA sequencing (RNAseq, Illumina) to define gene network abnormalities in RNA samples depleted of rRNA and isolated from cervical spinal cord sections of 7 ALS and 8 CTL samples. We aligned \u3e50 million 2X150 bp paired-end sequences/sample to the hg19 human genome and applied three different algorithms (Cuffdiff2, DEseq2, EdgeR) for identification of differentially expressed genes (DEG’s). Ingenuity Pathways Analysis (IPA) and Weighted Gene Co-expression Network Analysis (WGCNA) identified inflammatory processes as significantly elevated in our ALS samples, with tumor necrosis factor (TNF) found to be a major pathway regulator (IPA) and TNFα-induced protein 2 (TNFAIP2) as a major network “hub” gene (WGCNA). Using the oPOSSUM algorithm, we analyzed transcription factors (TF) controlling expression of the nine DEG/hub genes in the ALS samples and identified TF’s involved in inflammation (NFkB, REL, NFkB1) and macrophage function (NR1H2::RXRA heterodimer). Transient expression in human iPSC-derived motor neurons of TNFAIP2 (also a DEG identified by all three algorithms) reduced cell viability and induced caspase 3/7 activation. Using high-density RNAseq, multiple algorithms for DEG identification, and an unsupervised gene co-expression network approach, we identified significant elevation of inflammatory processes in ALS spinal cord with TNF as a major regulatory molecule. Overexpression of the DEG TNFAIP2 in human motor neurons, the population most vulnerable to die in ALS, increased cell death and caspase 3/7 activation. We propose that therapies targeted to reduce inflammatory TNFα signaling may be helpful in ALS patients
Endothelin-1 as a neuropeptide: neurotransmitter or neurovascular effects?
Endothelin-1 (ET-1) is an endothelium-derived peptide that also possesses potent mitogenic activity. There is also a suggestion the ET-1 is a neuropeptide, based mainly on its histological identification in both the central and peripheral nervous system in a number of species, including man. A neuropeptide role for ET-1 is supported by studies showing a variety of effects caused following its administration into different regions of the brain and by application to peripheral nerves. In addition there are studies proposing that ET-1 is implicated in a number of neural circuits where its transmitter affects range from a role in pain and temperature control to its action on the hypothalamo-neurosecretory system. While the effect of ET-1 on nerve tissue is beyond doubt, its action on nerve blood flow is often ignored. Here, we review data generated in a number of species and using a variety of experimental models. Studies range from those showing the distribution of ET-1 and its receptors in nerve tissue to those describing numerous neurally-mediated effects of ET-1
Patterns of cervical lymph node metastases in oral tongue squamous cell carcinoma: implications for elective and therapeutic neck dissection
Objectives: To determine the patterns of lymph node metastases in oral tongue carcinomas, and examine the implications for elective and therapeutic neck dissection
Patterns of cervical lymph node metastases in oral tongue squamous cell carcinoma: implications for elective and therapeutic neck dissection
Objectives: To determine the patterns of lymph node metastases in oral tongue carcinomas, and examine the implications for elective and therapeutic neck dissection
OP-154 EVALUATION OF LEFT VENTRICULAR DIASTOLIC FUNCTIONS ACCORDING TO NEW CRITERIA AND DETERMINANTS OF THOSE IN ACROMEGALY
A calculation of the Aharonov-Bohm wave function is presented. The result isa series of confluent hypergeometric functions which is finite at the forwarddirection
Choroidal thickness measurements in children with isolated growth hormone deficiency.
PurposeThe aim of this study was to determine the choroidal thickness measurement values in cases with isolated growth hormone deficiency (IGHD), to compare them with the healthy control group by using enhanced depth imaging optical coherence tomography (EDI-OCT), and to evaluate the effect of growth hormone (GH) treatment on choroid.Patients and methodsIn this study, 23 cases who were diagnosed with IGHD as a study group and 46 healthy subjects as a control group were included. All patients and controls underwent a complete ophthalmologic examination, including an examination with EDI-OCT. Choroidal thickness (CT) was measured at the fovea and at 1000 μm intervals from the foveal center in both temporal and nasal directions.ResultsThe mean subfoveal choroidal thickness (SFCT) was 329.04±88.49 μm in the cases with IGHD and 365.35±50.48 μm in the control group (P=0.033). The mean CT at temporal 1 and 2 mm were thinner in the IGHD group than that of control group (P=0.033 and P=0.043, respectively). Nasal quadrant measurements were also found to be thinner in the IGHD cases than that of control group, but the difference was not statistically significant. We found a significant positive correlation between pubertal staging and SFCT (rs=0.607, P=0.006). There was no statistically significant difference in CT values of the study group between before and 12 months after GH treatment (P>0.05).ConclusionThis study shows patients with IGHD has a thinner CT when compared with healthy pediatric cases. GH treatment seems to be not associated with the choroidal development
Submandibular gland invasion and feasibility of gland-sparing neck dissection in oral cavity carcinoma
Objective: This study investigated the incidence and routes of submandibular gland involvement in oral cavity carcinoma to determine the feasibility of submandibular gland sparing neck dissection
Submandibular gland invasion and feasibility of gland-sparing neck dissection in oral cavity carcinoma
Objective: This study investigated the incidence and routes of submandibular gland involvement in oral cavity carcinoma to determine the feasibility of submandibular gland sparing neck dissection