The Hot Spot

Top PDF The Hot Spot:

Transcription activity hot spot, is it real or an artifact?

Transcription activity hot spot, is it real or an artifact?

Based on the results from bin size 25, we further examined the functions of the 18 genes in the hot spot on chromo- some 14. We noted that the 8 out of 18 genes in the hot spot from the subset of expression phenotypes with pair- wise correlation smaller than 0.6 expressed "molecular binding" more specifically (Table 2). Two explanations are possible here, and results should be interpreted with care. First, for the genes that are indeed commonly regu- lated and are also highly correlated, when a subset of genes is removed, the true hot spot signal might be weak- ened. On the contrary, if the genes are not truly com- monly regulated but are highly correlated, after removing a subset of genes, the hot spots that remain significant might truly represent master regulation.

6 Read more

Vehicle incident hot spots identification: an approach for big data

Vehicle incident hot spots identification: an approach for big data

From Figure 1, several factors to establish an effective hot spot detector should be considered. Once a distance range is defined for the hot spot clusters, the solution is required to be accurate and complete; this means that all existing hot spots should be determined. Furthermore, the hot spot cluster centres should indicate with a certain degree of precision those areas where incidents take place frequently. In addition, it is required that the solution is general and adaptable to different types of incidents. In our case studies, for instance, we consider three different types of incidents (speed, harsh braking and harsh corners). These incidents have different characteristics and are likely to occur in distinct parts of the road (e.g., harsh braking and harsh corners are likely to happen in roundabouts or when there is a bend in the road, while speeding incidents occur with higher frequency in motorways). As more incident data is gathered, the method should be robust enough to modify the hot spot topology to a more current scenario, based on new information. The approach should also be noise-tolerant. Preferably, due to the large volumes of data considered and the industrial application, it is desirable that the solution is relatively low in complexity and fast to run.

8 Read more

Study on thermal model for calculating transformer hot spot temperature

Study on thermal model for calculating transformer hot spot temperature

These models are in the form of simple mathematical equations and were developed by simplifying the fundamental heat transfer equations and combining them with simplified transformer loss calculations. According to the loading guides, the hot spot temperature is calculated as the sum of the ambient temperature, the top oil temperature rise in tank, and the hot spot to top oil (in tank) temperature gradient. One assumption has been made in developing these thermal models are the variation in the oil viscosity with temperature can be neglected.

41 Read more

The effect of a localized geothermal heat source on deep water formation

The effect of a localized geothermal heat source on deep water formation

On the other hand, a stable vertical salinity gradient above the hot spot could theoratically counteract the destabilizing effect of this abyssal heat source, and thus suppress down- welling. However, according to field data (van Aken, 2007), the typical oceanic salinity profiles are such, that marked gra- dients are present only at the uppermost ∼ 100 m thick mix- ing layer, while in the deep ocean the salinity is basically ho- mogeneous, therefore the buoyancy differences in the vicin- ity of the seafloor are determined dominantly by the temper- ature field.

7 Read more

Influence of Reinforcement WT  % on Time Temperature Curve and Hot Spot Location

Influence of Reinforcement WT % on Time Temperature Curve and Hot Spot Location

Abstract: In the present work effect of the reinforcement on the time-temperature curve and hot spot location has been studied. Aluminium and SiCas molten metal material and reinforcement material have been considered in the present work while green sand a mould cavity material is considered. Reinforcement wt. % is varied from 0 to 15%. Thermal properties of aluminium are considered to be temperature dependent and green sand properties are considered to be temperature independent. Effective properties of the composite made from pure aluminium and SiC are calculated from physical mixture rule. Convective type of boundary condition has been considered on the walls of the mould cavity as they represent the actual physical scenario of the problem. Time-temperature curve has been plotted inside the casting part as well as inside the mould cavity.Temperature distribution is also plotted for different time intervals inside the casting assembly. From the results it has been found that hot spot occurs in case of pure aluminium (Al = 100%, SiC =0%), while its size gets lower with addition of the reinforcement in the base materials (Al = 95%, SiC =5%). Result also reveal that increment in reinforcement wt. % from 5 to 10 vanish the hot spot region from the casting.

9 Read more

Analytical criterion for shock ignition of fusion reaction in hot spot

Analytical criterion for shock ignition of fusion reaction in hot spot

This difference can be attributed to the oversimplifying assumptions of the model. The conditions in the simulations at the moment when the shock enters in the hot spot correspond to a temperature of several keV and a pressure of 10 Gbar. The shock Mach number at this moment is M 2. The value 1 /M 50% gives the estimate of the accuracy of the model. Moreover, in our simplified model the energy transport processes are accounted for as perturbations and the fuel density profile at stagnation may affect the results. Nevertheless, in spite of these simplifying assumptions, the model provides rather reasonable agreement with the full hydrodynamical simulations. That proves that it accounts quite well for the basic physics relevant for shock ignition. It describes the pressure amplification corresponding to the non-isobaric fuel configuration and provides reasonable estimates for the ignition conditions.

6 Read more

Blob Statistics and SVD based plasma-wall interaction detection in Tokamak

Blob Statistics and SVD based plasma-wall interaction detection in Tokamak

Our algorithm is developed with the aim to detect abnormal events during Tokamak operation with focus on detecting plasma-wall interaction (hot spot) with the use of single vision camera. Fig.1 represents a typical case of hot spot detection. Fig.1 (a) shows frame number 1343 from video shot 28980. Fig.1 (b) shows the cropped- binary image for the same frame having blobs. The gas-puff reflection is observed as small blob at the bottom. The hot spot is differentiated from the gas-puff and its reflection by using area and centroid statistics of the blobs as per our proposed algorithm. The detected hot spot and gas-puff with its reflection are presented in the binary images in Fig.1(c) and (d), respectively. Finally, the SVD is applied on the hot spot and its location along x-axis and y-axis is found from the width of the pulse seen in Fig.1 (e) and (f). The height of the pulse represents the value of first principle component along specified direction. For this frame, the pulse exists between 33 and 33.5 along x-axis means it exists between 330th and 335th column of the original frame. Similarly, for y-axis the pulse exists between 101th to 110th rows of the original frame.

12 Read more

Calculation of the Factor of Stress Concentration in the Junction’s Welded Tube Subjected to Combined Loadings

Calculation of the Factor of Stress Concentration in the Junction’s Welded Tube Subjected to Combined Loadings

Figure 10: Concentration of bending stresses in the plane. The concentration in this case, changing gradually from the saddle point to a maximum value (kt = 5.06) at an angle Φ=90° and then begins to decrease until crown point. We note here that the hot spot is not located at the crown point as the other two cases, but in the saddle point figure 11.

7 Read more

A model for (quasi )periodic multi wavelength photometric variability in young stellar objects

A model for (quasi )periodic multi wavelength photometric variability in young stellar objects

In the magnetospheric accretion model, material from the accretion disk fl ows onto the surface of the star following magnetic fi eld lines. In a stable model, a slightly tilted large- scale magnetosphere truncates the disk, and the infalling material creates two ordered hot spots separated by 180 ° in azimuth where the fl ow hits the surface of the star ( Romanova et al. 2008 ) . We set the size of the hot spot to be the median size estimated by Gullbring et al. ( 1998 ) of 0.7% of the surface area of the star. For a spot temperature of 10 4 K this gives an accretion rate of 9.21 × 10 −8 M e yr −1 , where we use Equations ( 4 )–( 7 ) from Whitney et al. ( 2013 ) relating spot size, temperature, and accretion rate. While this accretion rate of our initial model is higher than typical cTTS ( Herczeg & Hillenbrand 2008; Ingleby et al. 2014; Manara et al. 2014 ) and would require a dipole fi eld larger than has currently been observed in cTTS, we fi nd that models with lower accretion rates reduce the amplitude but do not alter the shape of the variability in our simulations ( e.g., see Models 3 and 4 in Table 1 and Figure 2 ) . The star-spot temperature contrast may be larger than in some of our models because accretion hot spots are often found within large cool spots ( Donati et al. 2007 ) . We do not include cool spots in our models; however, future model developments should explore their inclusion. Venuti et al. ( 2015 ) estimate that  10% of observed light curves in the actively accreting ( de fi ned by observed UV excesses ) cTTS sample are dominated by cool spots. In systems with accretion, we expect the effect of cool spots to be less dominant since their amplitudes are only around 0.1 mag in the r band ( Cody et al. 2014 ) . The contrast in optical is much higher than in the infrared bands ( Cody et al. 2014 ) , so the variability pattern in the IRAC bands will be dominated by the circumstellar effects we have modeled.

15 Read more

Spatial chemical conservation of hot spot interactions in protein-protein complexes

Spatial chemical conservation of hot spot interactions in protein-protein complexes

Here, we have shown that spatially conserved physico- chemical interactions play a crucial functional role. We have presented a computational method, MAPPIS, for rec- ognition of such patterns of conserved interactions formed between groups of atoms independent of the identity of the amino acids as well as the overall protein sequences and folds. Considering multiple complexes of functionally similar PPIs, MAPPIS allows the identifica- tion of the smallest set of interactions that may be respon- sible for binding and function. We have shown that chemical groups that form spatially conserved interac- tions correlate with cooperative effects in double mutant cycles and are useful for predicting hot spots. Interestingly, we observed that increasing the number of the compared PPIs, as well as comparing PPIs of proteins with different overall sequences and folds, improves the specificity of the hot spot prediction. The main limitation of our approach is the requirement for the existence of a sufficient number of high resolution structures of com- plexes comprised by functionally similar proteins. The selection of such complexes is not straightforward, espe- cially as there is no direct correspondence between func- tional similarity and the similarity of the overall sequences and structures [32].

11 Read more

Application of Combustion Hot Spot Analysis to Process Furnace with Arbor Coils

Application of Combustion Hot Spot Analysis to Process Furnace with Arbor Coils

Hot spots are among the most serious operational issues in furnaces as they may result in the destruction of tubes. Hence, it is essential to locate such hot spots precisely on the tube surfaces inside the industrial furnaces in order to secure a safe design and operation. In the current study, we have extended the model proposed by Talmor in order to precisely locate the combustion hot spots on the surface of the tubes inside process furnaces with arbor coils. These furnaces are mostly used in catalytic reforming units. The Talmor model is one of the best models for analyzing combustion hot spots on the tube surfaces of industrial furnaces. This model is developed by considering the furnace geometry and arrangement (tube arrangements and burner positions). In the current paper, we have derived and extended the equations formulated by Talmor for furnaces with arbor coil. As the second step, a specific furnace already installed in a catalytic conversion unit of a refinery has been selected for the sake of modeling. The modeling of the preceding furnace was completed using the code prepared for this purpose. The results have been used not only for analyzing the hot spots but also to model the heat flux profile inside the furnace. Upon modeling the furnace, the location of the hot spot on the 20 th coil was predicted which was consistent with the experimental results.

11 Read more

Malaria risk in Corsica, former hot spot of malaria in France

Malaria risk in Corsica, former hot spot of malaria in France

temperature variations [35]. Pre-adult stages of this spe- cies have been found in these larval habitats from June to October although Toumanoff & Rageau [17] and Jau- jou [13] have reported that females can lay eggs as early as February. In Morocco, the species can lay several times a year with up to seven hatching cycles [36]. In Corsica, at least three generations in one year have been observed [37], the annual number of generations depending on local climatic conditions [38,39]. In Cor- sica, An. labranchiae hibernates in the adult form [13]. According to Sautet [39], diapause is not systematic and hibernation is induced by low temperature. Reproduc- tion could occur during winter: in the laboratory, egg-layinghas occurred during winter months at a tem- perature of 16°C [39]. In addition, females engorged with blood (including human blood) have been found in the middle of winter [13]. It seems impossible that eggs could survive the winter, but eggs laid at the end of the hot season have greater resistance to low temperatures and are more likely to hatch [40].

8 Read more

Why is the H3+ hot spot above Jupiter's Great Red Spot so hot?

Why is the H3+ hot spot above Jupiter's Great Red Spot so hot?

Recent observations of Jupiter’s Great Red Spot indicate that the thermosphere above the storm is hotter than its surroundings by more than 700 K. Possible suggested sources for this heating have thus far included atmospheric gravity waves and lightning-driven acoustic waves. Here, we propose that Joule heating, driven by Great Red Spot vorticity penetrating up into the lower stratosphere and coupling to the thermosphere, may contribute to the large observed temperatures. The strength of Joule heating will depend on the local inclination angle of the magnetic field and thus the observed emissions and inferred temperatures should vary with planetary longitude as the Great Red Spot tracks across the planet.

11 Read more

Yield Improvement of Cast Part Using Computer Aided Casting Simulation

Yield Improvement of Cast Part Using Computer Aided Casting Simulation

engineers in foundry to assure quality of cast parts and yield optimization without charging out shop floor trails, it also helps engineers to analyzing and optimizing of feedability of a casting during design phase. Casting simulation helps to visualize mould filling, solidification of casting and to predict the hot spot location where internal defects such as shrinking porosity. An internal defect occurs at the time of solidification, these internal defects can be eliminated by proper design of feed system. Yield is the ability of casting to manufacture acceptable casting in effective manner. Improved yield offers many benefits as material cost, better process control. By using computer casting simulation, an optimum gating and feeding system can be designed to improve yield, quality of casting and also eliminate internal defects. In this paper feed system is designed to eliminate hot spot location from the casting of pulp valve body part that is Guide face.

5 Read more

Silencing Homologous RNA Recombination Hot Spots with GC-Rich Sequences in Brome Mosaic Virus

Silencing Homologous RNA Recombination Hot Spots with GC-Rich Sequences in Brome Mosaic Virus

Importantly, however, not all homologous regions can sup- port recombination in BMV (7, 17, 21). Characterization of BMV-derived and artificial recombination hot spots revealed that most of the precise and imprecise recombination events occurred within or close to short AU-rich sequences (20, 21). AU-rich sequences alone, when present on both recombining RNAs, were, however, only moderately active in homologous recombination. High recombination frequency was observed when, in addition to common AU-rich sequences, the recom- bining RNAs contained similar sequences of average or higher GC content (21). The relative positions of the common AU- rich and the less common AU-rich (i.e., GC-rich or average AU1GC content) sequences were also important factors, with the AU-rich sequences being located at the downstream loca- tion and the less AU-rich sequences being located at the up- stream location in the most favored homologous recombina- tion hot spots (21) (see also Fig. 1). In the proposed model, the BMV replicase may occasionally pause (stall) within or in the vicinity of the AU-rich sequence while copying the negative strand of RNA3. During the pause, the replicase may march backward on the primary template (12, 18, 21), thus allowing the 39 end of the positive-stranded incomplete nascent RNA to dissociate from the primary template because of the weak A-U base pairing. Subsequently, the free 39 end of the nascent strand may hybridize to the complementary target region present in negative-stranded acceptor RNA2. This model pro- poses that the role for the less AU-rich (GC-rich or average AU1GC content) upstream common regions would be to fa- cilitate (stabilize) the hybridization of the nascent RNA with the complementary region in the acceptor RNA during the template switch (21). The final step in recombination is the resumption of strand elongation by the BMV replicase on the acceptor template (21).

9 Read more

Saturation Mapping of a Gene-Rich Recombination Hot Spot Region in Wheat

Saturation Mapping of a Gene-Rich Recombination Hot Spot Region in Wheat

Physical mapping of wheat chromosomes has revealed small chromosome segments of high gene density and frequent recombination interspersed with relatively large regions of low gene density and infrequent recombination. We constructed a detailed genetic and physical map of one highly recombinant region on the long arm of chromosome 5B. This distally located region accounts for 4% of the physical size of the long arm and at least 30% of the recombination along the entire chromosome. Multiple crossovers occurred within this region, and the degree of recombination is at least 11-fold greater than the genomic average. Characteristics of the region such as gene order and frequency of recombination appear to be conserved throughout the evolution of the Triticeae. The region is more prone to chromosome breakage by gametocidal gene action than gene-poor regions, and evidence for genomic instability was implied by loss of gene collinearity for six loci among the homeologous regions. These data suggest that a unique level of chromatin organization exists within gene-rich recombination hot spots. The many agronomically important genes in this region should be accessible by positional cloning.

13 Read more

Risk Factor and Cluster Analysis to Identify Malaria Hot Spot for Control Strategy in Samigaluh Sub-District, Kulon Progo,  Indonesia

Risk Factor and Cluster Analysis to Identify Malaria Hot Spot for Control Strategy in Samigaluh Sub-District, Kulon Progo, Indonesia

Cluster analysis was used in several malaria re- search (3, 18, 19), some of them prove that clus- ter analysis was potentially tool to guide deter- mining malaria intervention strategy by the poli- cymaker. Refer to Satscan analysis; there was a significant cluster in the southeast of Samigaluh II that fall in the malaria hot spot (Fig. 2). Sami- galuh is hilly sub-district (4); people live in the settlement which is majority presence of multiple agriculture on their field (20). This statement was confirmed by the screenshot from Google Earth that shown majority of the area is in green colour indicating the plantation. Additionally, close to the cluster, presence the river that possibly as breeding place of the mosquitos. Accordingly, several factors may cause the cluster significant: first was the existence of proper Anopheles habitat and second was the ownership of risky occupa- tion to malaria infection. In short, translating cluster finding on the implementation section was done by considering the number of the household included as in Satscan result. This number reflected the malaria prevalence on this cluster (13).

7 Read more

Online Full Text

Online Full Text

Abstract— The researchers proposed to develop a mechanism in mining an Online Graphical Information System (GIS) for crime rate and models using frequent pattern analysis. It is a web-based system that includes GIS for robbery, homicide and physical injury incidents within Iloilo City. This system can help police identify where and what time crime frequently happen. It generates who are the frequent victims in the community. The main focus of the proposed system is the analysis of frequent crime patterns and its association rules and crime hot spots. Results show the hot spots which displays clustered crimes in the Google Map. It uses the Google Heat Map layer in clustering plotted crimes. These hot spots are showing the density of crime. Furthermore, the system is able to generate frequent patterns of crimes. This uses Apriori algorithm in generating the results.

5 Read more

The Meiotic Recombination Hot Spot ura4A in Schizosaccharomyces pombe

The Meiotic Recombination Hot Spot ura4A in Schizosaccharomyces pombe

in which all four products of single meioses can be The frequency of homologous recombination varies individually recovered and analyzed (Paques and Haber widely from interval to interval along the genome. DNA 1999). The fate of the four chromatids in a diploid cell regions with lower or higher than average frequency of undergoing meiosis can be followed by tetrad analysis. aberrant segregation and crossing over are called cold Examination of the segregation of genetic markers in spots or hot spots, respectively. They have been identi- tetrads has demonstrated two classes of recombination fied and described in many different organisms (Lichten events: the classical reciprocal exchange of DNA se- and Goldman 1995; Paques and Haber 1999; Petes quences, called crossing over, and the unidirectional trans- 2001). Specific nucleotide sequences have been identi- fer of genetic information between chromatids, desig- fied in some cases, which are recognized by proteins nated non-Mendelian segregation (NMS). Two types of promoting, directly or indirectly, a rate-limiting step of NMS events are distinguished. One is the nonreciprocal the recombination process (Smith 2001).

12 Read more

Show all 10000 documents...