An Empirical Study of Program Modification Histories

Large programs undergo many changes before they run in a satisfactory manner. For many large programs, modification histories are kept which record every change that is made to the program. By studying these records, patterns of program evolution can be identified. This paper describes a taxonomy of types of changes which was developed by studying several such histories. In addition, it discusses a possible application of this classification in an interactive tool for the updating of user documentation.MIT Artificial Intelligence Laborator

Modification methylase M.Sau3239I from Streptomyces aureofaciens 3239

AbstractBy chromatography on phosphocellulose and Heparin-Sepharose the modification methylase M.Sau3239I was detected and partly purified from cells of Streptomyces aureofaciens 3239. Methylation by this enzyme protects DNA from cleavage by the restriction endonuclease R.Sau3239I. The enzyme catalyzes methylation of adenine to N-6-methyladenine in the 5'-CTCGmAG-3' recognition sequence

Automated Program Recognition: A Proposal

The key to understanding a program is recognizing familiar algorithmic fragments and data structures in it. Automating this recognition process will make it easier to perform many tasks which require program understanding, e.g., maintenance, modification, and debugging. This paper proposes a recognition system, called the Recognizer, which automatically identifies occurrences of stereotyped computational fragments and data structures in programs. The Recognizer is able to identify these familiar fragments and structures even though they may be expressed in a wide range of syntactic forms. It does so systematically and efficiently by using a parsing technique. Two important advances have made this possible. The first is a language-independent graphical representation for programs and programming structures which canonicalizes many syntactic features of programs. The second is an efficient graph parsing algorithm.MIT Artificial Intelligence Laborator

Earlier emergence of a temperature response to mitigation by filtering annual variability

The rate of global surface warming is crucial for tracking progress towards global climate targets, but is strongly influenced by interannual-to-decadal variability, which precludes rapid detection of the temperature response to emission mitigation. Here we use a physics based Green's function approach to filter out modulations to global mean surface temperature from sea-surface temperature (SST) patterns, and show that it results in an earlier emergence of a response to strong emissions mitigation. For observed temperatures, we find a filtered 2011-2020 surface warming rate of 0.24 °C per decade, consistent with long-term trends. Unfiltered observations show 0.35 °C per decade, partly due to the El Nino of 2015-2016. Pattern filtered warming rates can become a strong tool for the climate community to inform policy makers and stakeholder communities about the ongoing and expected climate responses to emission reductions, provided an effort is made to improve and validate standardized Green's functions. © 2022. The Author(s)

The Ozone Hole Indirect Effect: Cloud-Radiative Anomalies Accompanying the Poleward Shift of the Eddy-Driven Jet in the Southern Hemisphere

This study quantifies the response of the clouds and the radiative budget of the Southern Hemisphere (SH) to the poleward shift in the tropospheric circulation induced by the development of the Antarctic ozone hole. Single forcing climate model integrations, in which only stratospheric ozone depletion is specified, indicate that (1) high-level and midlevel clouds closely follow the poleward shift in the SH midlatitude jet and that (2) low-level clouds decrease across most of the Southern Ocean. Similar cloud anomalies are found in satellite observations during periods when the jet is anomalously poleward. The hemispheric annual mean radiation response to the cloud anomalies is calculated to be approximately +0.25 W m−2, arising largely from the reduction of the total cloud fraction at SH midlatitudes during austral summer. While these dynamically induced cloud and radiation anomalies are considerable and are supported by observational evidence, quantitative uncertainties remain from model biases in mean-state cloud-radiative processes

A Survey on Approximation Mechanism Design without Money for Facility Games

In a facility game one or more facilities are placed in a metric space to serve a set of selfish agents whose addresses are their private information. In a classical facility game, each agent wants to be as close to a facility as possible, and the cost of an agent can be defined as the distance between her location and the closest facility. In an obnoxious facility game, each agent wants to be far away from all facilities, and her utility is the distance from her location to the facility set. The objective of each agent is to minimize her cost or maximize her utility. An agent may lie if, by doing so, more benefit can be obtained. We are interested in social choice mechanisms that do not utilize payments. The game designer aims at a mechanism that is strategy-proof, in the sense that any agent cannot benefit by misreporting her address, or, even better, group strategy-proof, in the sense that any coalition of agents cannot all benefit by lying. Meanwhile, it is desirable to have the mechanism to be approximately optimal with respect to a chosen objective function. Several models for such approximation mechanism design without money for facility games have been proposed. In this paper we briefly review these models and related results for both deterministic and randomized mechanisms, and meanwhile we present a general framework for approximation mechanism design without money for facility games

Гуморальна та клітинна ланки природного захисту організму корів різної селекції породи лімузин

The problem of animal resistance has recently become increasingly important as the genetic potential of newly developed dairy cattle breeds has increased, and the animals are highly susceptible to various diseases, metabolic disorders, and disruptions in general homeostasis. This contributes to a significant culling of cows, prevents their planned selection, and, in turn, slows down the pace of breeding work. The state of natural resistance in animals is determined by nonspecific protective factors of their organism, which depend on several factors: species, breed, physiological state, conditions of care, housing, feeding, individual and constitutional characteristics, etc. The research aimed to study the natural resistance of Limousin cows of different selections. The studies were conducted at Lvivske LLC, Lviv region, on Limousin cows of Hungarian, Polish, and Ukrainian breeding. The natural resistance of the controlled animals was studied by analyzing the complex cellular and humoral blood factors in the third month after calving, according to the methods described in the reference book Laboratory Research Methods in Biology, Animal Husbandry, and Veterinary Medicine. It was found that Limousin cows of domestic and imported breeding differed in terms of natural resistance. In particular, the phagocytic activity of blood neutrophils, the phagocytic index, the phagocytic number, and the lysozyme and bactericidal activity of blood serum were highest in cows of Ukrainian breeding. However, their superiority in these traits over Polish and Hungarian breeding animals was statistically insignificant in almost all cases. A slightly higher level of protective functions in animals of the Ukrainian Limousin breed is also indicated by a higher number of T-lymphocytes, including T-helper cells. On the other hand, the number of T-suppressors was lower in Ukrainian cows by 3.1 % and 1.4 %, respectively, compared to Hungarian and Polish breeding animals. The immunoregulatory index in the controlled cows, depending on their country of breeding, ranged from 1,85 to 2,74, with the highest value observed in domestically bred individuals and the lowest in animals imported from Poland.Проблема резистентності великої рогатої худоби останнім часом набуває все більшої актуальності, позаяк із підвищенням генетичного потенціалу в корів спостерігається висока схильність до різних захворювань, порушення обміну речовин і загального гомеостазу, що спричиняє вибракування тварин, не дає можливості проводити їх плановий добір, а це своєю чергою зменшує темпи селекційної роботи. Стан природної резистентності тварин визначають неспецифічні захисні фактори їхнього організму, які залежать від низки чинників: виду, породи, фізіологічного стану, умов догляду, утримання і годівлі, індивідуальних і конституціональних особливостей тощо. Метою досліджень було вивчити природну резистентність корів породи лімузин різної селекції. Дослідження проведені в умовах ТзОВ “Львівське” Львівської області на коровах породи лімузин угорської, польської та української селекції. Природну резистентність підконтрольних тварин вивчали за комплексом клітинних і гуморальних факторів крові на третьому місяці після отелення за методиками, описаними в довіднику “Лабораторні методи досліджень у біології, тваринництві та ветеринарній медицині”. Встановлено, що корови породи лімузин вітчизняної та імпортної селекції відрізнялися за показниками природної резистентності. Зокрема, фагоцитарна активність нейтрофілів крові, фагоцитарний індекс та фагоцитарне число, лізоцимна та бактерицидна активність сироватки крові найвищими були у корів української селекції, втім їх перевага за цими ознаками над тваринами польської і угорської селекції майже у всіх випадках була невірогідною. Про дещо вищий рівень захисних функцій організму у тварин породи лімузин української селекції свідчить також вища кількість Т-лімфоцитів, у тому числі Т-хелперів. Натомість кількість Т-супресарів, навпаки, нижчою була у корів української селекції відповідно на 3,1 та 1,4 % порівняно із тваринами угорської і польської селекції. Імунорегуляторний індекс у підконтрольних корів, залежно від країни їх селекції, перебував у межах 1,85–2,74, причому найвище його значення спостерігалося в особин вітчизняної селекції, а найнижче  – у тварин, завезених з Польщі

Do evolutionary algorithms indeed require random numbers? Extended study

An inherent part of evolutionary algorithms, that are based on Darwin theory of evolution and Mendel theory of genetic heritage, are random processes. In this participation, we discuss whether are random processes really needed in evolutionary algorithms. We use n periodic deterministic processes instead of random number generators and compare performance of evolutionary algorithms powered by those processes and by pseudo-random number generators. Deterministic processes used in this participation are based on deterministic chaos and are used to generate periodical series with different length. Results presented here are numerical demonstration rather than mathematical proofs. We propose that a certain class of deterministic processes can be used instead of random number generators without lowering of evolutionary algorithms performance. © Springer International Publishing Switzerland 2013

Multi-channel Transformers for Multi-articulatory Sign Language Translation

Sign languages use multiple asynchronous information channels (articulators), not just the hands but also the face and body, which computational approaches often ignore. In this paper we tackle the multi-articulatory sign language translation task and propose a novel multi-channel transformer architecture. The proposed architecture allows both the inter and intra contextual relationships between different sign articulators to be modelled within the transformer network itself, while also maintaining channel specific information. We evaluate our approach on the RWTH-PHOENIX-Weather-2014T dataset and report competitive translation performance. Importantly, we overcome the reliance on gloss annotations which underpin other state-of-the-art approaches, thereby removing future need for expensive curated datasets