Unexpected gene activation following CRISPR-Cas9-mediated genome editing

The discovery of the Clustered Regularly-Interspaced Short Palindromic Repeats (CRISPR) and its development as a genome editing tool has revolutionized the field of molecular biology. In the DNA damage field, CRISPR has brought an alternative to induce endogenous double-strand breaks (DSB) at desired genomic locations and study the DNA damage response and its consequences. Many systems for sgRNA delivery have been reported in order to efficiency generate this DSB, including lentiviral vectors. However, some of the consequences of these systems are yet not well understood. Here we report that lentiviral-based sgRNA vectors can integrate into the endogenous genomic target location, leading to undesired activation of the target gene. By generating a DSB in the regulatory region of the ABCB1 gene using a lentiviral sgRNA vector, we can induce the formation of taxol-resistant colonies. We show that these colonies upregulated ABCB1 via integration of the EEF1A1 and the U6 promoters from the sgRNA vector. We believe that this is an unreported CRISPR/Cas9 artefact that researchers need to be aware of when using lentiviral vectors for genome editing.

Gradient Damage Analysis of a Cylinder Under Torsion: Bifurcation and Size Effects

In this work, an elastic-damage evolution analysis is carried out for a cylinder under torsion made of a material obeying a gradient damage model with softening. Both semi-analytical and asymptotic approaches are developed to analyze the elastic, axisymmetric and bifurcation stages. We show the existence of a fundamental branch where the damage field is asymmetric and localized within a finite thickness from the boundary. By minimizing a generalized Rayleigh quotient, the bifurcation time and modes are obtained as a function of the length scale $\epsilon =\ell /R$ ϵ = ℓ / R involving a material internal length and the cylinder radius. We will then focus on these size effects by assuming that $\epsilon $ ϵ is a small parameter in an asymptotic setting. After justification, specific spatial and temporal rescaled variables are introduced for the boundary layer problem. It is shown that the axisymmetric damage evolution and the bifurcation are governed by two universal functions independent of the length scale. The simulation results obtained by the semi-analytical approach are formally justified by the asymptotic methods.

APPLICATION OF RAINFLOW TECHNIQUES TO THE DESIGN AND OPERATION OF PORT INFRASTRUCTURE

The concept of rainflow comes from the fatigue damage field where it has demonstrated its appropriateness (see Johannesson, 1999). In port engineering, rainflow counting has shown some serious advantages over traditional methods such as the zero-downcrossing method but it is not widely used. This work aims at showing some applications of this technique to problems detected in port operation and reliability after briefly introducing the concept.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/_gwjsDd3yiE

Performance Evaluation of Power Weeder in Sugarcane Crop

Weeding is an important and labour intensive agricultural operation and about 1/3rd of the cost of cultivation is accounted towards weed control operation alone. Any delay and negligence in weeding operation effects the crop yields up to 30-40%. Today the agricultural sector requires non-chemical weed control that safeguards consumers demand for high quality food products and pay special attention to food safety. The objectives of the study was to evaluate the performance of power weeder by evaluating the energy consumption and cost economics of power weeder in sugarcane crop. The evaluation was conducted at soil different moisture contents at 30,45 and 60 days after sowing (DAS) at different speeds of weeder. The bulk density decreased from 0.84 to 0.65 g cm-3 with increased soil moisture content from 7±1 to 12±1 per cent. The field capacity of power weeder varied from 0.0347 to 0.137 ha h-1 when operated with 3 forward speeds at 30, 45 and 60 DAS. The weeding efficiency of power weeder is in the range of 98.74 to 91.22% at 0.584 km h-1, 96.80 to 84.93% at 1.35 km h-1 and 94.67 to 73.72% at 4.153 km h-1. The minimum and maximum plant damage is observed at a forward speeds of 0.584 km h-1 and 4.153 km h-1. When operated at lower speeds the plant damage will be minimum whereas operating at high speeds will result in maximum plant damage. Field machine index of the weeder is observed as 0.83, 0.82 and 0.864 for 30, 45 and 60 DAS. The cost of weeding per hectare is calculated as Rs.3,878 ha-1 and Rs.8000 ha-1 for mechanical and traditional weeding, respectively. It can be started and operated by farmer or any unskilled labour with ease. Also working with power weeder in between the rows is easy with a very less maintenance cost.

Effect of Sepatronium Bromide (YM-155) on DNA Double-Strand Breaks Repair in Cancer Cells

Survivin, as an antiapoptotic protein often overexpressed in cancer cells, is a logical target for potential cancer treatment. By overexpressing survivin, cancer cells can avoid apoptotic cell death and often become resistant to treatments, representing a significant obstacle in modern oncology. A survivin suppressor, an imidazolium-based compound known as YM-155, is nowadays studied as an attractive anticancer agent. Although survivin suppression by YM-155 is evident, researchers started to report that YM-155 is also an inducer of DNA damage introducing yet another anticancer mechanism of this drug. Moreover, the concentrations of YM-155 for DNA damage induction seems to be far lower than those needed for survivin inhibition. Understanding the molecular mechanism of action of YM-155 is of vital importance for modern personalized medicine involving the selection of responsive patients and possible treatment combinations. This review focuses mainly on the documented effects of YM-155 on DNA damage signaling pathways. It summarizes up to date literature, and it outlines the molecular mechanism of YM-155 action in the context of the DNA damage field.

Improved Empirical Formulation for Seabed Trench Profile at Touchdown Zone and its Effects on Fatigue of Steel Catenary Risers

Steel catenary risers (SCRs) offer a cost-effective solution to deep water deployments. Hanging from a floater, an SCR is commonly subjected to large tension at hangoff location and large bending moments at touchdown zone (TDZ) which lead to fatigue damage. Field observations showed that the depth of a seabed trench might reach to a depth of four to five times of the diameter of a riser, however, a flat seabed was often assumed for the modeling of SCRs which surely affects simulations of fatigue behavior of the SCR at the touchdown zone. Studies on the effects of seabed trench on TDZ fatigue conducted by different researchers led to contradictory conclusions, i.e., some studies suggested that considering seabed trench reduced fatigue damage at TDZ of SCRs, while, others drew opposing conclusions. The contradiction may be explained by factors including inappropriate trench profiles and different sea states assumed in the analysis model. An iterative procedure initially developed by Wang and Low and further improved in the present work was used to estimate the position and the length of a seabed trench beneath an SCR and, then, an improved empirical formulation was generated to approximate the profile of the seabed trench. Additionally, dynamic simulations were conducted to study the effects of seabed trench on fatigue behaviors of SCRs encountering variant directional waves.

An FFT-based spectral solver for interface decohesion modelling using a gradient damage approach

This work presents a fast Fourier transform (FFT) based method that can be used to model interface decohesion. The inability of an FFT solver to deal with sharp interfaces discards the use of conventional cohesive zones to model the interfacial mechanical behaviour within this framework. This limitation is overcome by approximating sharp interfaces (e.g. grain/phase boundaries) with an interphase. Within the interphase, the background plastic constitutive behaviour is inherited from the respective adjacent grains. The anisotropic kinematics of the decohesion process is modelled using a damage deformation gradient that is constructed by mapping the opening strains (in normal and tangential modes) to the associated projection tensors. The degradation (damage) of the interfacial opening resistances is modelled via a dimensionless nonlocal damage variable that prevents localisation of damage within the interphase. This nonlocal variable results from the solution of a gradient damage based regularisation equation within the interphase subdomain. The damage field is constrained to the interphase region by applying a relatively large penalisation on the damage gradients inside the interphase. The extent of nonlocality ensures that the damage is largely uniform in the direction perpendicular to the interphase, thus making its thickness the theoretical lengthscale for dissipation. To achieve model predictions that are objective with respect to the interphase thickness, scaling relations of the model parameters are proposed. The numerical performance is shown for a uniform opening case and then for a propagating crack. Finally, an application to an artificial polycrystal is shown.

A methodology to conduct wind damage field surveys for high impact weather events from convective origin

Post-event damage assessments are essential to document the effects of high-impact weather events such as floods or strong wind events. Moreover, evaluating the damage and characterizing its extension and intensity can be helpful for further analysis such as completing a diagnostic meteorological case study. This paper presents a methodology to perform field surveys of damage caused by strong winds of convective origin, i.e. tornado, downburst and other types of convective winds. It is based on previous studies and also on 136 fieldworks performed by the authors in Spain from 2004 to 2018. The methodology includes the systematic collection of pictures and records of damages on man-made structures and on vegetation, as well as collection of any available Automatic Weather Station data, witness reports and images of the phenomenon and their location and orientation. Three final deliverables are proposed to synthesize the data recorded: (i) A summary of the fieldwork; (ii) A table consisting of detailed geolocated information about each damage, and (iii) A map or a .kml file containing the previous information ready for graphical display and further analysis. This methodology has been applied by the authors in the past, sometimes only a few hours after the event occurrence and, in many occasions, when the type of convective phenomenon (e.g. tornado, downburst) was uncertain. In the latter case the information resulting from this methodology has proofed very useful to discern the phenomenon type, based on the damage patterns particularly if no witness reports were available. The application of systematic methodologies as the one presented here is necessary in order to build homogeneous databases of severe weather cases and high impact weather events.

Valuasi Ekonomi Kerusakan Lingkungan Akibat Kebakaran Gambut Di Desa Mak Teduh Provinsi Riau

Peat fires caused negative impact which link to the death of flora, soil damage and smoke disasters.The research proposed to know how big the danger at environment due to forest fire. Unfortunately has so way research found how much money last during burning which link to end damage. Field observation and soil samples were taken through purposive sampling. The result of research show that fire cause a total death of flora and fauna and subsidence of 10-20 cm. This study showed that land fires significantly affected organic C, bulk density, and total microorganisms, and significanlyt effecedt on pH and respiration parameters. Our results clearly demonstrate the severe enviromental destruction due to on peat fire as it fulfill. The order to know the significance of the vegetation impact of fire that we use PP 4/2004. The order to know the significant of the negative impact of fire the we use PP 4/2004 for soil pH, organic C, bulk density, porosity, water content, total microorganisms, and respiration with the economic valuation ofer, damage due to fire was reached Rp1.765.190.064,-.Keywords : enviromental damage, economic valution. peat fires, soil properties