Aryl hydrocarbon receptor-mediated down-regulation of Sox9b causes jaw malformation in zebrafish embryos

ABSTRACT Exposure to environmental contaminants can disrupt normal development of the early vertebrate skeleton. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) impairs craniofacial skeletal development across many vertebrate species, and its effects are especially prominent in early life stages of fish. TCDD activates the aryl hydrocarbon receptor, a transcription factor that mediates most if not all TCDD responses. We investigated the transcriptional response in the developing zebrafish jaw after TCDD exposure using DNA microarrays. Zebrafish larvae were exposed to TCDD at 96 h after fertilization, and jaw cartilage tissue was harvested for microarray analysis at 1, 2, 4, and 12 h after exposure. Numerous chondrogenic transcripts were misregulated by TCDD in the jaw. Comparison of transcripts altered by TCDD in jaw with transcripts altered in embryonic heart showed that the transcriptional responses in the jaw and the heart were strikingly different. Sox9b, a critical chondrogenic transcription factor, was the most significantly reduced transcript in the jaw. We hypothesized that the TCDD reduction of sox9b expression plays an integral role in affecting the formation of the embryonic jaw. Morpholino knockdown of sox9b expression demonstrated that partial reduction of sox9b expression alone was sufficient to produce a TCDD-like jaw phenotype. Loss of a single copy of the sox9b gene in sox9b(ϩ/Ϫ) heterozygotes increased sensitivity to jaw malformation by TCDD. Finally, embryos injected with sox9b mRNA and then exposed to TCDD blocked TCDD-induced jaw toxicity in approximately 14% of sox9b-injected embryos. These results suggest that reduced sox9b expression in TCDD-exposed zebrafish embryos contributes to jaw malformation. Zebrafish (Danio rerio) are a vertebrate model species commonly used to study development. This model has since proven useful in other areas, including pharmacology, drug discovery, and toxicology The receptor for TCDD is the aryl hydrocarbon receptor (AHR). Although the molecular mechanisms that cause TCDD toxicity remain poorly understood, the toxic effects are generally considered to be mediated by AH

Interpretasi Lingkungan Pengendapan Formasi Talang Akar Berdasarkan Data Cutting dan Wireline Log pada Lapangan X Cekungan Sumatera Selatan

A sedimentary environment is a part of earth\u27s surface which is physically, chemically and biologically distinct from adjacent terrains (Selley, 1988). The study of the depositional environment is one goal of many studiesconducted for academic purpose and economically purpose in oil and gas exploration. The study of the depositionalenvironment requires a fairly comprehensive analysis as to sequencestratigraphy facies analysis to obtain detailedinterpretations or conclusions. The purpose of this study is to analyze cutting and wireline logs to determinelithology, facies and sedimentation history of theTalang Akar formation field X in South Sumatra basin. The method used to analyze the formation of depositional environment of Talang Akar field X in SouthSumatra basin is the cutting description in order to know the composition of the constituent formations. While theanalysis conducted is cutting analysis to get lithofacies interpretation, second is well log analysis method to getsubsurface data such as physical rock properties then electrofacies analysis based on gamma ray log pattern andthird is stratigraphy sequence analysis method so sea level changed can be known. Stratigraphy sequenceinterpretation did base on facies and gamma ray log pattern changed. Pratama-1 well lithology consists of shale, siltstone, very fine sandstone until medium sandstone andlimestones. While the well lithology Pratama-2 is composed of shale, very fine until medium sandstone and siltstone.Facies found in wells Pratama-1 consists of distributary channel fill, prodelta, distal bar, distributary mouth bar,and marsh. Facies in wells Pratama-2 is a mud flat and mixed flat. In Pratama-1 wells are 2 sets sequence that bounded by 2 sequence boundary, with a stratigraphic unit LST, TST and HST with progradation andretrogradation stacking patterns. While the Pratama-2 wells contained one stratigraphic unit sequence that is onlyTST in progradation and agradation stacking patterns. Based on this analysis the Talang Akar formation field X inSouth Sumatra basin has a transitional depositional environment

Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

Measurement of the top quark mass using charged particles in pp collisions at root s=8 TeV

Peer reviewe

Measurement of t(t)over-bar normalised multi-differential cross sections in pp collisions at root s=13 TeV, and simultaneous determination of the strong coupling strength, top quark pole mass, and parton distribution functions

Peer reviewe

Search for supersymmetry in events with one lepton and multiple jets in proton-proton collisions at root s=13 TeV

Peer reviewe

An embedding technique to determine ττ backgrounds in proton-proton collision data

An embedding technique is presented to estimate standard model tau tau backgrounds from data with minimal simulation input. In the data, the muons are removed from reconstructed mu mu events and replaced with simulated tau leptons with the same kinematic properties. In this way, a set of hybrid events is obtained that does not rely on simulation except for the decay of the tau leptons. The challenges in describing the underlying event or the production of associated jets in the simulation are avoided. The technique described in this paper was developed for CMS. Its validation and the inherent uncertainties are also discussed. The demonstration of the performance of the technique is based on a sample of proton-proton collisions collected by CMS in 2017 at root s = 13 TeV corresponding to an integrated luminosity of 41.5 fb(-1).Peer reviewe

Measurement of the Splitting Function in &ITpp &ITand Pb-Pb Collisions at root&ITsNN&IT=5.02 TeV

Data from heavy ion collisions suggest that the evolution of a parton shower is modified by interactions with the color charges in the dense partonic medium created in these collisions, but it is not known where in the shower evolution the modifications occur. The momentum ratio of the two leading partons, resolved as subjets, provides information about the parton shower evolution. This substructure observable, known as the splitting function, reflects the process of a parton splitting into two other partons and has been measured for jets with transverse momentum between 140 and 500 GeV, in pp and PbPb collisions at a center-of-mass energy of 5.02 TeV per nucleon pair. In central PbPb collisions, the splitting function indicates a more unbalanced momentum ratio, compared to peripheral PbPb and pp collisions.. The measurements are compared to various predictions from event generators and analytical calculations.Peer reviewe