Discrete analogue computing with rotor-routers

Rotor-routing is a procedure for routing tokens through a network that can implement certain kinds of computation. These computations are inherently asynchronous (the order in which tokens are routed makes no difference) and distributed (information is spread throughout the system). It is also possible to efficiently check that a computation has been carried out correctly in less time than the computation itself required, provided one has a certificate that can itself be computed by the rotor-router network. Rotor-router networks can be viewed as both discrete analogues of continuous linear systems and deterministic analogues of stochastic processes.Comment: To appear in Chaos Special Focus Issue on Intrinsic and Designed Computatio

Сравнительный анализ результатов различных способов резекции головки поджелудочной железы при хроническом панкреатите

Background In more than half of cases of chronic pancreatitis (CP), enlargement of the pancreatic head is diagnosed with the presence of complications that serve as an indication for organ resection. The development of an optimal method for the surgical treatment of CP with damage to the pancreatic head (PH) is one of the tasks of surgical pancreatology.Aim of study To perform comparative evaluation of immediate and late results of different types of PH resection in CP.Material and methods A prospective controlled study was conducted with a comparative analysis of the results of surgical treatment of 131 patients with CP with pancreatic head enlargement. In 29% (n=38) cases inflammatory complications were revealed, in 86.3% (n=113), they have been associated with compression of adjacent organs, jaundice also developed (n=60), as well as duodenal obstruction at the level of duodenum (n=43), regional portal hypertension (n=10). A total of 47 pancreatoduodenal, 58 subtotal, and 26 partial resections of the pancreas were performed.Results Duodenum preserving pancreatic head resections had significantly better short-term results compared to pancreatoduodenal resections. Subtotal PH resection in the Bern’s version was superior to all other resections in terms of average duration of surgery, postoperative inpatient treatment, and intraoperative blood loss. The frequency of relaparotomy for intraperitoneal complications of hemorrhagic etiology was 8.2% (n=4). The frequency of the adverse effect according to pain preservation 5 years after duodenum preserving resection tract was 0.125; after pancreatoduodenal resection - 0.357 with a statistically significant relative risk (RR) of 0.350 (CI95% = 0.13–0.98). According to other indicators of clinical long-term surgical treatment depending on the various methods of PH resection, there were no statistically significant differences (p>0.05). The quality of life of patients 5 years after the operation according to the EORTC QLQ-C30 questionnaire was statistically significant (p=0.0228) by only two indicators: dyspnea (DY:8.3) and insomnia (SL:16.67; 27.4) with higher values after operations of Beger and the Bern’s version of the subtotal PH resection, respectively.Актуальность Более чем в половине наблюдений хронического панкреатита (ХП) диагностируется увеличение головки поджелудочной железы (ПЖ) с наличием осложнений, которые служат показанием к резекции органа. Разработка оптимального способа хирургического лечения ХП с поражением головки поджелудочной железы (ГПЖ) является одной из задач хирургической панкреатологии.Цель Провести сравнительную оценку непосредственных и отдаленных результатов различных способов резекции ГПЖ при ХП.Материал и методы Выполнено проспективное контролируемое исследование со сравнительным анализом результатов хирургического лечения 131 пациента с ХП с увеличением размеров ГПЖ. В 29% (n=38) наблюдений у больных присутствовали осложнения воспалительного характера, в 86,3% (n=113) они были связаны с компрессией соседних органов, в том числе диагностированы механическая желтуха (n=60), непроходимость на уровне двенадцатиперстной кишки (ДПК) (n=43), и региональная портальная гипертензия (n=10). Проведено 47 панкреатодуоденальных, 58 субтотальных и 26 частичных резекций ГПЖ.Результаты При дуоденосохраняющих резекциях ГПЖ получены статистически значимо лучшие непосредственные результаты по сравнению с панкреатодуоденальными резекциями. Субтотальная резекция ГПЖ в бернском варианте превосходила все остальные дуоденосохраняющие резекции по показателям средней продолжительности операции, послеоперационного стационарного лечения, интраоперационной кровопотери. Частота релапаротомий по поводу внутрибрюшных осложнений геморрагического характера при этом составила 8,2% (n=4). Частота неблагоприятного эффекта по параметру сохранения боли через 5 лет после дуоденосохраняющих резекций ГПЖ составила 0,125, а после панкреатодуоденальной резекции — 0,357 при статистически значимой величине относительного риска (RR), равной 0,350 (ДИ 95%=0,13–0,98). По остальным показателям клинических отдаленных результатов хирургического лечения в зависимости от различных способов резекции ГПЖ статистически значимых различий получено не было (p>0,05). Качество жизни больных через 5 лет после операции, согласно анкете EORTC QLQ-C30, статистически значимым  (р=0,0228) получено только по двум показателям: одышка (DY:8,3) и бессонница (SL:16,67;27,4) с более высокими значениями после операций Beger и бернского варианта субтотальной резекции ГПЖ соответственно

On the Red-Green-Blue Model

We experimentally study the red-green-blue model, which is a sytem of loops obtained by superimposing three dimer coverings on offset hexagonal lattices. We find that when the boundary conditions are ``flat'', the red-green-blue loops are closely related to SLE_4 and double-dimer loops, which are the loops formed by superimposing two dimer coverings of the cartesian lattice. But we also find that the red-green-blue loops are more tightly nested than the double-dimer loops. We also investigate the 2D minimum spanning tree, and find that it is not conformally invariant.Comment: 4 pages, 7 figure

Reference performance test Methodology for degradation assessment of lithium-sulfur batteries

Lithium-Sulfur (Li-S) is an emerging battery technology receiving a growing amount of attention due to its potentially high gravimetric energy density, safety, and low production cost. However, there are still some obstacles preventing its swift commercialization. Li-S batteries are driven by different electrochemical processes than commonly used Lithium-ion batteries, which often results in very different behavior. Therefore, the testing and modeling of these systems have to be adjusted to reflect their unique behavior and to prevent possible bias. A methodology for a Reference Performance Test (RPT) for the Li-S batteries is proposed in this study to point out Li-S battery features and provide guidance to users how to deal with them and possible results into standardization. The proposed test methodology is demonstrated for 3.4 Ah Li-S cells aged under different conditions

Using domain-independent problems for introducing formal methods

The key to the integration of formal methods into engineering practice is education. In teaching, domain-independent problems i.e., not requiring prior engineering background-offer many advantages. Such problems are widely available, but this paper adds two dimensions that are lacking in typical solutions yet are crucial to formal methods: (i) the translation of informal statements into formal expressions; (ii) the role of formal calculation (including proofs) in exposing risks or misunderstandings and in discovering pathways to solutions. A few example problems illustrate this: (a) a small logical one showing the importance of fully capturing informal statements; (b) a combinatorial one showing how, in going from "real-world" formulations to mathematical ones, formal methods can cover more aspects than classical mathematics, and a half-page formal program semantics suitable for beginners is presented as a support; (c) a larger one showing how a single problem can contain enough elements to serve as a Leitmotiv for all notational and reasoning issues in a complete introductory course. An important final observation is that, in teaching formal methods, no approach can be a substitute for an open mind, as extreme mathphobia appears resistant to any motivation

Непосредственные и отдаленные результаты оригинальных способов продольной панкреатоеюностомии с расширением площади анастомозирования панкреатоеюнального соустья

RELEVANCE. The dependency results of draining operations on the efficcacy of drainig of ductal system of the pancreas and adequate outflow of the pancreatic juce through anastomosis are undoubtful, therefore the development of new techniques of longitudinal pancreatojejunostomy (LPJ) extending area of anastomosis is an actual challenge.AIM OF STUDY. To compare the immediate and long-term results of longitudinal pancreatojejunostomy with the expansion of the area of anastomosis in patients with chronic pancreatitis.MATERIAL AND METHODS. We analysed immediate and long-term results of LPJ in 58 patients with chronic pancreatitis with impaired patency of the major pancreatic duct (MPD) without the head enlargement.RESULTS. All patients were divided into two groups: comparison group ( n=26, operated up to 2008 ) and main group (n=32, operated stumps during the MPD diastasis and posterior pancreatic surface (n=3) into anastomosis, with resection of the anterior pancreatic surface in the form of triangular fragments (n=11), with circulation of the small intestine loop during the recovery phase (n=19). The original LPJ in the study group of patients did not lengthened the surgery (160 [135, 185]) and intraoperative blood loss (265 [175, 340]). In the main group of patients there was no postoperative complications and fatal outcomes, but the average duration postoperative hospital treatment (18 [16; 20.5]) exceeded some data of foreign and domestic authors. Pain within 5 years after surgery in patients of the main group exceeded 26.6% and the appearance of diarrheal syndrome with dependance from reception of enzyme preparations was twice lower than in patients og the comparison group. According to questionnaire EORTC QLQ-C30, 5 years after surgery statistically significant differences between groups in terms of scales CF, NV, DY (p=0.03, 0.02, 0.006 respectively), indicating the advantage of intervention performed in the mail group.CONCLUSIONS. 1. An indication for longitudinal pancreatojejunostomy in chronic pancreatitis is impaired patency of the main pancreatic duct in the absence of an increase and inflammatory mass in the pancreatic head.2. The width of the main pancreatic duct is less than 5 mm and the presence of diastasis between its proximal and distal stumps with the posterior surface of the pancreas preserved, is not a reason for refusing longitudinal pancreatic jujunostomy in favor of the resection method.3. The expansion of pancreatojejunal anastomosis when performing longitudinal pancreatojejunostomy can improve the immediate and longterm results of surgical treatment for chronic pancreatitis.АКТУАЛЬНОСТЬ. Зависимость результатов дренирующих операций от эффективности дренирования протоковой системы поджелудочной железы (ПЖ) и адекватности оттока панкреатического сока через анастомоз не вызывает сомнений, в связи с чем разработка новых способов продольной панкреатоеюностомии (ППЕС), расширяющих площадь панкреатоеюнального соустья, является актуальной задачей.ЦЕЛЬ ИССЛЕДОВАНИЯ. Сравнить непосредственные и отдаленные результаты ППЕС с расширением площади панкреатоеюнального соустья у больных хроническим панкреатитом (ХП).МАТЕРИАЛ И МЕТОДЫ. Проведен анализ непосредственных и отдаленных результатов лечения 58 больных ХП с нарушением проходимости главного панкреатического протока (ГПП) на всем протяжении без увеличения головки поджелудочной железы (ГПЖ), оперированных в объеме ППЕС. Все больные были распределены на две группы: сравнения (n=26, оперированные до 2008 г.) и основную (n=32, оперированные после 2008 г. с использованием новых способов ППЕС: с включением в единое панкреатоеюнальное соустье дистальной и проксимальной культей при диастазе ГПП и задней поверхности ПЖ (n=3), с иссечением передней поверхности ПЖ в виде фрагментов треугольной формы (n=11), с циркуляцией петли тонкой кишки на восстановитель- ном этапе операции (n=19).РЕЗУЛЬТАТЫ. Применение оригинальных способов ППЕС в основной группе больных не удлинило среднюю продолжительность операции (160 [135; 185]) и интраоперационную кровопотерю (265 [175; 340]). В основной группе больных не было послеоперационных осложнений и летальности, но средняя продолжительность послеоперационного стационарного лечения (18 суток [16; 20,5]) превысила данные некоторых зарубежных и отечественных авторов. Купирование боли через 5 лет после операции у больных основной группы превысило на 26,6%, а развитие диарейного синдрома с зависимостью от приема ферментных препаратов оказалось вдвое ниже, чем у больных группы сравнения. По данным анкетирования EORTC QLQ-C30, через 5 лет после операции установлены статистически значимые межгрупповые различия по показателям шкал CF, NV, DY (р=0,03; р=0,02; р=0,006 соответственно), что указывает на преимущество вмешательства, примененного в основной группе.ВЫВОДЫ. 1. Показанием к продольной панкреатоеюностомии при хроническом панкреатите является нарушение проходимости главного панкреатического протока при отсутствии увеличения и воспалительной массы в головке поджелудочной железы.2. Ширина главного панкреатического протока менее 5 мм и наличие диастаза между его прок- симальной и дистальной культями при сохраненной задней поверхности поджелудочной железы не являются поводом для отказа от продольной панкреатоеюностомии в пользу резекционного метода.3. Расширение площади панкреатоеюнального соустья при выполнении продольной панкреатоеюностомии позволяет улучшить непосредственные и отдаленные результаты хирургического лечения хронического панкреатита

Criminal narrative experience: relating emotions to offence narrative roles during crime commission

A neglected area of research within criminality has been that of the experience of the offence for the offender. The present study investigates the emotions and narrative roles that are experienced by an offender while committing a broad range of crimes and proposes a model of Criminal Narrative Experience (CNE). Hypotheses were derived from the Circumplex of Emotions (Russell, 1997), Frye (1957), Narrative Theory (McAdams, 1988) and its link with Investigative Psychology (Canter, 1994). The analysis was based on 120 cases. Convicted for a variety of crimes, incarcerated criminals were interviewed and the data were subjected to Smallest Space Analysis (SSA). Four themes of Criminal Narrative Experience (CNE) were identified: Elated Hero, Calm Professional, Distressed Revenger and Depressed Victim in line with the recent theoretical framework posited for Narrative Offence Roles (Youngs & Canter, 2012). The theoretical implications for understanding crime on the basis of the Criminal Narrative Experience (CNE) as well as practical implications are discussed

Noisy Monte Carlo: Convergence of Markov chains with approximate transition kernels

Monte Carlo algorithms often aim to draw from a distribution $\pi$ by simulating a Markov chain with transition kernel $P$ such that $\pi$ is invariant under $P$. However, there are many situations for which it is impractical or impossible to draw from the transition kernel $P$. For instance, this is the case with massive datasets, where is it prohibitively expensive to calculate the likelihood and is also the case for intractable likelihood models arising from, for example, Gibbs random fields, such as those found in spatial statistics and network analysis. A natural approach in these cases is to replace $P$ by an approximation $\hat{P}$. Using theory from the stability of Markov chains we explore a variety of situations where it is possible to quantify how 'close' the chain given by the transition kernel $\hat{P}$ is to the chain given by $P$. We apply these results to several examples from spatial statistics and network analysis.Comment: This version: results extended to non-uniformly ergodic Markov chain