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Two World Poultry Congresses have been held in the United States, in 1939 and 1974. The USA Branch of the World's Poultry Science Association was not formed until after the first of those. In order to recognise the contributions o...
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Two World Poultry Congresses have been held in the United States, in 1939 and 1974. The USA Branch of the World's Poultry Science Association was not formed until after the first of those. In order to recognise the contributions of the many who have been active, this review of the history of the USA Branch was prepared. It gives the objectives of the organisation, the officers during the 35 years and a list of some of the more important activities.
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Many authors have claimed that short branches in the Tree of Life will be very difficult to resolve with strong support, even with the large multilocus data sets now made possible by genomic resources. Short branches may be especi...
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Many authors have claimed that short branches in the Tree of Life will be very difficult to resolve with strong support, even with the large multilocus data sets now made possible by genomic resources. Short branches may be especially problematic because the underlying gene trees are expected to have discordant phylogenetic histories when the time between branching events is very short. Although there are many examples of short branches that are difficult to resolve, surprisingly, no empirical studies have systematically examined the relationships between branch lengths, branch support, and congruence among genes. Here, we examine these fundamental relationships quantitatively using a data set of 20 nuclear loci for 50 species of snakes (representing most traditionally recognized families). A combined maximum likelihood analysis of the 20 loci gives strong support for 69% of the nodes, but many remain weakly supported, with bootstrap values for 20% ranging from 21% to 66%. For the combined-data tree, we find significant correlations between the length of a branch, levels of bootstrap support, and the proportion of genes that are congruent with that branch in the separate analyses of each gene. We also find that strongly supported conflicts between gene trees over the resolution of individual branches are common (roughly 35% of clades), especially for shorter branches. Overall, our results support the hypothesis that short branches may be very difficult to confidently resolve, even with large, multilocus data sets. Nevertheless, our study provides strong support for many clades, including several that were controversial or poorly resolved in previous studies of snake phylogeny.
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In theory, branch predictors with more complicated algorithms and larger data structures provide more accurate predictions. Unfortunately, overly large structures and excessively complicated algorithms cannot be implemented becaus...
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In theory, branch predictors with more complicated algorithms and larger data structures provide more accurate predictions. Unfortunately, overly large structures and excessively complicated algorithms cannot be implemented because of their long access delay. To date, many strategies have been proposed to balance delay with accuracy, but none has completely solved the issue. The architecture for ahead branch prediction (A~2BP) separates traditional predictors into two parts. First is a small table located at the front-end of the pipeline, which makes the prediction brief enough even for some aggressive processors. Second, operations on complicated algorithms and large data structures for accurate predictions are all moved to the back-end of the pipeline. An effective mechanism is introduced for ahead branch prediction in the back-end and small table update in the front. To substantially improve prediction accuracy, an indirect branch prediction algorithm based on branch history and target path (BHTP) is implemented in A~2BP. Experiments with the standard performance evaluation corporation (SPEC) benchmarks on gem5/SimpleScalar simulators demonstrate that A~2BP improves average performance by 2.92% compared with a commonly used branch target buffer-based predictor. In addition, indirect branch misses with the BHTP algorithm are reduced by an average of 28.98% compared with the traditional algorithm.
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In the modern microprocessors that designed with pipeline stages, the performance of these types of processors will be affected when executing branch instructions, because in this case there will be stalls in the pipeline. In turn...
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In the modern microprocessors that designed with pipeline stages, the performance of these types of processors will be affected when executing branch instructions, because in this case there will be stalls in the pipeline. In turn this causes in reducing the Cycle Per Instruction (CPI) of the processor. In the case of executing a branch instruction, the processor needs an extra clocks to know if that branch will happen (Taken) or not (Not Taken) and also it requires calculating the new address in the case of the branch is Taken. The prediction that the branch is T / NT is an important stage in enhancing the processor performance. In this research more than one method of branch prediction (hybrid) is used and the designed circuit will choose different types of prediction algoritms depending on the type of the branch. Some of these methods were used are static while the other are dynamic. All circuits were built practically and examined by applying different programs on the designed predictor algorithm to compute the performance of the processor.
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This paper considers a modification of the branch-and-cut algorithm for Mixed Integer Linear Programming where branching is performed on general disjunctions rather than on variables. We select promising branching disjunctions bas...
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This paper considers a modification of the branch-and-cut algorithm for Mixed Integer Linear Programming where branching is performed on general disjunctions rather than on variables. We select promising branching disjunctions based on a heuristic measure of disjunction quality. This measure exploits the relation between branching disjunctions and intersection cuts. In this work, we focus on disjunctions defining the mixed integer Gomory cuts at an optimal basis of the linear programming relaxation. The procedure is tested on instances from the literature. Experiments show that, for a majority of the instances, the enumeration tree obtained by branching on these general disjunctions has a smaller size than the tree obtained by branching on variables, even when variable branching is performed using full strong branching.
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? 2023 Elsevier B.V.Glucansucrase AP-37 was extracted from the culture supernatant of Lactobacillus kunkeei AP-37 and characteristics of the glucan produced by the active glucansucrase in terms of structural and functional roles w...
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? 2023 Elsevier B.V.Glucansucrase AP-37 was extracted from the culture supernatant of Lactobacillus kunkeei AP-37 and characteristics of the glucan produced by the active glucansucrase in terms of structural and functional roles were determined in this study. A molecular weight around 300 kDa was observed for glucansucrase AP-37 and its acceptor reactions with maltose, melibiose and mannose were also conducted to unveil the prebiotic potential of the poly-oligosaccharides formed via these reactions. The core structure of glucan AP-37 was determined by 1H and 13C NMR and GC/MS analysis which revealed that glucan AP-37 was a highly branched dextran composing of high levels of (1 → 3)-linked α-D-glucose units with low levels of (1 → 2)-linked α-D-glucose units. The structural features of the glucan formed, demonstrated that glucansucrase AP-37 was an α-(1 → 3) branching sucrase. Dextran AP-37 was further characterised by FTIR analysis and XRD analysis demonstrated its amorphous nature. A fibrous compact morphology was observed for dextran AP-37 with SEM analysis whereas TGA and DSC analysis revealed its high stability as no degradation was observed up to 312 °C. Finally, the prebiotic potential of the dextran AP-37 and the gluco-oligosaccharides produced with the acceptor reaction of α-(1 → 3) branching sucrase AP-37 were determined and promising results were found for the gluco-oligosaccharides to act as prebiotics.
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The demands for high-performance microprocessors have recently increased. Accurate branch prediction is one of the most important factors for high-performance processors. In order to predict branch outcomes, instruction program co...
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The demands for high-performance microprocessors have recently increased. Accurate branch prediction is one of the most important factors for high-performance processors. In order to predict branch outcomes, instruction program counter bits and the history of recently executed branch outcomes are used. Among the executed branch outcomes, some histories are useful while others are useless. In addition, these useful/useless histories vary among branch instructions. Numerous studies have shown a method that identifies optimal history. However, little research has been done regarding the treatment of useless history. In this paper, a new method called Instruction Address alloyed History Length Modification branch predictor is proposed to handle the useless history bits. When PHT entries are 4,096, IAaHLM has a prediction accuracy of 93.22% and Gshare has a prediction accuracy of 91.84%.
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The conditional branch has long been considered an expensive operation. The relative cost of conditional branches has increased as recently designed machines are now relying on deeper pipelines and higher multiple issue. Reducing ...
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The conditional branch has long been considered an expensive operation. The relative cost of conditional branches has increased as recently designed machines are now relying on deeper pipelines and higher multiple issue. Reducing the number of conditional branches executed often results in a substantial performance benefit. This paper describes a code-improving transformation to reorder sequences of conditional branches that compare a common variable to constants. The goal is to obtain an ordering where the fewest average number of branches in the sequence will be executed. First, sequences of branches that can be reordered are detected in the control flow. Second, profiling information is collected to predict the probability that each branch will transfer control out of the sequence. Third, the cost of performing each conditional branch is estimated. Fourth, the most beneficial ordering of the branches based on the estimated probability and cost is selected. The most beneficial ordering often includes the insertion of additional conditional branches that did not previously exist in the sequence. Finally, the control flow is restructured to reflect the new ordering. The results of applying the transformation are on average reductions of about 8% fewer instructions executed and 13% branches performed, as well as about a 4% decrease in execution time.
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After the Bank Charter Act in 1833, English banks could branch nationally without legal or geographical restriction. It has been previously thought that despite this freedom, early English joint-stock banks predominantly began as ...
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After the Bank Charter Act in 1833, English banks could branch nationally without legal or geographical restriction. It has been previously thought that despite this freedom, early English joint-stock banks predominantly began as single units. Drawing upon a new data set, this article maps the growth of branch banking, the size of bank networks and their geographical location and spread. It demonstrates that banks pursued branching strategies energetically against the intentions of regulators and were successful in forming large and complex networks. However, ultimately, before 1880 the majority settled for local, district and multi-regional structures, as opposed to national structures.
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This paper considers a modification of the branch-and-cut algorithm for Mixed Integer Linear Programming where branching is performed on general disjunctions rather than on variables. We select promising branching disjunctions bas...
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This paper considers a modification of the branch-and-cut algorithm for Mixed Integer Linear Programming where branching is performed on general disjunctions rather than on variables. We select promising branching disjunctions based on a heuristic measure of disjunction quality. This measure exploits the relation between branching disjunctions and intersection cuts. In this work, we focus on disjunctions defining the mixed integer Gomory cuts at an optimal basis of the linear programming relaxation. The procedure is tested on instances from the literature. Experiments show that, for a majority of the instances, the enumeration tree obtained by branching on these general disjunctions has a smaller size than the tree obtained by branching on variables, even when variable branching is performed using full strong branching.
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