Analytical theory of coherent synchrotron radiation wakefield of short bunches shielded by conducting parallel plates

We develop a general model of coherent synchrotron radiation (CSR) impedance with shielding provided by two parallel conducting plates. This model allows us to easily reproduce all previously known analytical CSR wakes and to expand the analysis to the situations not explored before. It reduces calculations of the impedance to taking integrals along the trajectory of the beam. New analytical results are derived for the radiation impedance with shielding for the following orbits: a kink, a bending magnet, a wiggler of finite length, and an infinitely long wiggler. All our formulas are benchmarked agains numerical simulations with the CSRZ computer code

Is there a relationship between mental distress and cognitive impairment in temporal lobe epilepsy?

Hintergrund: Depression und kognitive Beeinträchtigung liegen oft gleichzeitig bei Patienten mit Temporallappenepilepsie (TLE) vor. Ob eine komorbide Depression bei Patienten mit TLE mit kognitiver Beeinträchtigung zusammenhängt, ist bislang nicht eindeutig geklärt. Falls es einen solchen Zusammenhang gibt, bleibt zudem die Frage offen, ob dieser Zusammenhang von depressiver Symptomatik im Speziellen oder dem Ausmaß an psychischer Belastung im Allgemeinen abhängig ist. Im Rahmen der vorliegenden Dissertation wurde untersucht, inwieweit selbstberichtete depressive Symptomatik und psychische Belastung mit verschiedenen kognitiven Funktionen bei Patienten mit TLE zusammenhängen. Methodik: Es wurden 162 Patienten mit unilateraler TLE in die retrospektive Untersuchung eingeschlossen, davon 95 Patienten mit linksseitiger TLE und 67 Patienten mit rechtsseitiger TLE. Zur Bestimmung der Schwere der depressiven Symptomatik wurde das Beck Depressionsinventar verwendet. Das Ausmaß an psychischer Belastung wurde mit der Symptom-Checkliste-90-R erfasst. Bivariate Spearman-Rangkorrelationen wurden zwischen depressiver Symptomatik sowie psychischer Belastung und den kognitiven Maßen für verbalen Abruf, figurales Lernen, psychomotorische Geschwindigkeit und phonematische Wortflüssigkeit berechnet. Das Signifikanzniveau wurde für multiples Testen adjustiert (p < 0.0063). Ergebnisse: Neunzehn Prozent der Patienten gaben klinisch relevante depressive Symptome an, 17 Prozent der Patienten berichteten klinisch relevante psychische Belastung. Das Ausmaß an psychischer Belastung korrelierte hoch mit der Schwere der depressiven Symptomatik (rs = 0.80, p < 0.001). Es fanden sich keine signifikanten Zusammenhänge zwischen depressiver Symptomatik oder psychischer Belastung und den Maßen für kognitive Leistungsfähigkeit. Ergänzende post-hoc Analysen ergaben eine starke negative Korrelation zwischen depressiver Symptomatik und figuralem Lernen, jedoch nur innerhalb der Gruppe von Patienten ohne strukturelle Auffälligkeiten in der Magnetresonanztomographie (MRT-negative TLE) rs = - 0.55, p = 0.003). Schlussfolgerungen: Im Gegensatz zu einigen früheren Studien mit kleineren Stichproben fand die vorliegende Arbeit keinen Zusammenhang zwischen depressiver Symptomatik und kognitiver Beeinträchtigung bei Patienten mit unilateraler TLE. Ebenso ergab sich kein Zusammenhang zwischen psychischer Belastung und kognitiver Beeinträchtigung. Diese Ergebnisse sprechen gegen theoretische Annahmen über einen kausalen Zusammenhang zwischen Depression und kognitiver Beeinträchtigung sowie gegen einen gemeinsamen Pathomechanismus für beide Konditionen bei Patienten mit TLE. Ob eine MRT-negative TLE den Zusammenhang zwischen depressiver Symptomatik und kognitiver Beeinträchtigung moderiert, sollte in zukünftigen Studien weiter untersucht werden.Objective: Depression and cognitive impairment often co-exist among patients with temporal lobe epilepsy (TLE). However, there is still debate whether comorbid depression is related to cognitive impairment in patients with TLE. Even if there is a relationship, it is still unclear whether this relationship depends on symptoms of depression specifically, or rather symptoms of mental distress in general. In the present study, we examined whether self-rated symptoms of depression and of mental distress are related to different cognitive functions in patients with TLE. Methods: We retrospectively studied 162 patients with unilateral TLE (95 patients with left TLE and 67 patients with right TLE). Severity of symptoms of depression and of mental distress were measured with the Beck Depression Inventory and the Symptom Checklist-90-Revised, respectively. Bivariate Spearman’s rank correlations were calculated between these two measures and cognitive measures of verbal recall, figural learning, psychomotor speed, and phonemic word fluency. Due to multiple testing, a corrected level of p < 0.0063 was regarded as significant, only. Results: Nineteen and 17 percent of patients reported meaningful symptoms of depression and of mental distress, respectively. Mental distress highly correlated with symptoms of depression (rs = 0.80, p < 0.001). We found no significant correlations of either symptoms of depression or mental distress with measures of cognitive function. Complementary post-hoc analyses revealed a strong negative correlation between depressive symptoms and figural learning, yet only in those patients without evidence of structural abnormalities in magnetic resonance imaging (MRI-negative TLE) (rs = - 0.55, p = 0.003). Conclusions: In contrast to some former studies with smaller sample sizes, the present study could not detect a relationship between depression and cognitive impairment in patients with unilateral TLE. Likewise, mental distress and cognition were unrelated in this sample of patients. These results may argue against theoretical models claiming a causal link between depression and cognitive impairment or a common pathogenic mechanism for these conditions in patients with TLE. Whether MRI-negative TLE actually moderates the relationship between depressive symptoms and cognitive impairment should be further examined in future studies

Analysis of game engines

This paper presents an analysis of the most popular game engines for indie game developmentВ данной работе представлен анализ наиболее популярных игровых движков для инди-разработки иг

Improving technology for manufacturing casting case of truck clutch release cylinder

The object of research: Manufacturing technology of body castings for trucks using the example of a clutch release cylinder body made of gray cast iron with flake graphite EN-GJL-200. Investigated problem: Finding ways to reduce the weight and size characteristics of cast parts. The main scientific results: A mathematical model has been developed that has made it possible to determine the optimal compositions of alloying Cr/Ni – Cu/Ti complexes that ensure an increase in the grade of cast iron by increasing the tensile strength at elevated carbon contents. This makes it possible in the future to reduce the thickness of the walls of the castings, achieving a reduction in their weight and size characteristics The area of practical use of the results of the study: Automotive industry in terms of technology for manufacturing cast parts for trucks Innovative technological product: Improved technology for manufacturing the clutch release cylinder body due to optimization of melt technology and out-of-furnace processing allows for targeted selection of melt processing modes, ensuring an increase in the strength characteristics of cast iron for cast body parts, thereby moving from the EN-GJL-200 cast iron grade to the EN grade -GJL-250 and EN-GJL-300. The scope of the innovative technological product: Foundries of engineering enterprises, in particular those producing trucks, in which iron castings are produce

Cortical Bone Tissue Engineering;Scaffold Design and Cell Selection

Cortical bone tissue engineering provides a promising approach to generate graft materials needed to treat the large sized bone defects. The underling premise of tissue engineering is to mimic the in vivo microenvironment as best as possible in vitro culture system. To select an appropriate scaffold material used in this model system, mechanical and hydraulic permeability properties of 316L porous stainless steel and polymethylmethacrylate (PMMA) were studied, as well as their biocompatibility in short and long term cell culture. Results showed that scaffolds made of both stainless steel and PMMA: (1) could be manufactured to have similar permeability as that cortical bone, (2) exhibited biocompatibility in short term cell culture and that as the ultimate tensile strength was concerned, the scaffold made of stainless steel was similar to cortical bone while not PMMA and that as the elastic modulus was concerned, neither scaffolds made of stainless steel or PMMA was similar to cortical bone. To establish an optimal culture condition and select an appropriate cell source, the influence of an artificial osteoid layer made from type I collagen and fibronectin on the osteogenesis of bone marrow and periosteum cells were studied. Results showed that more extracellular matrix and calcium minerals were deposited in cultures on the artifical osteoid layer than on conventional 2D plastic and that polarity of cell density distribution occurred in cultures on the artifical osteoid layer while not on 2D plastic and that there was no significant difference of the osteogenesis between the cultures of bone marrow cells and periosteum cell

CONSTRUCTING THE PARAMETRIC FAILURE FUNCTION OF THE TEMPERATURE CONTROL SYSTEM OF INDUCTION CRUCIBLE FURNACES

The objects of the study were diagnostic features that allow determining the quality of controlling temperature modes of induction crucible melting. For this, in the normalized space of feature factors, which are the content of SiO2&nbsp;and FeO+Fe2O3&nbsp;in slag, a discriminant function is constructed and a decision rule is obtained in the form of a linear classifier, which allows determining in which mode the process was carried out. It is shown that this rule is the basis for identifying an event qualified as a parametric failure, and it can be included in the general structure of the parametric failure function. The parametric failure function constructed for the temperature control system of induction crucible melting makes it possible to ascertain that the control system does not meet the specified requirements for a specific temperature mode of melting. The mechanism of inferencing regarding the occurrence of a parametric failure based on this function is as follows. If the decision rule showed that the object belongs to the “low-temperature mode” class, although the process under these conditions should have been carried out in the high-temperature mode, a parametric failure is recorded. In this case, the numerical value of this function takes the value of “1”, otherwise – “0”. The inferencing mechanism works similarly if, on the basis of the decision rule, it is revealed that the process was carried out in the high-temperature mode, although under these conditions it should have been carried out in the low-temperature mode. Based on the constructed parametric failure function, practical problems related to planning maintenance of the temperature control system integrated into the melting complex or organizational and technical measures aimed at minimizing violations of the melting regulations can be solve

On Authoritarian Political Representation in Contemporary China

Both in the Party Charter and in the State Constitution, the Chinese Communist Party claims to represent the Chinese people. Instead of treating this claim as mere rhetoric made by the party for propaganda purposes, this article demonstrates that it indicates a rather significant transition in the party’s understanding of its relationship with the people. Particularly, roughly about two decades into the Open and Reform policy initiated under the leadership of Deng Xiaoping, the party made a strategic choice in imagining itself as the representative of the people instead of the revolutionary vanguard. This change in the language was very remarkable in the post-1949 Chinese history, in the sense that the party no longer considers itself as the facilitator of proletariat revolution, but as the authoritarian representative in the political community. If representation means "re-presentation", as in bringing something absent present, this appears to be what the party tries to do. By embodying the nation, the party tries to represent both the rich and the poor, acting as the arbiter of forever present discords and conflicts within the society. Clearly, this representation has nothing to do with what people usually call "democratic" representation. But considering that representation and democracy are conceptually rooted in very different sources, exploring "authoritarian representation" in contemporary China would enable us to better understand both China and democratic representation

Experimental and industrial method of synthesis of optimal control of the temperature region of cupola melting

The object of research is the temperature regime of melting in a cupola. The synthesis of optimal control of such an object is associated with the presence of a problem consisting in the complexity of its mathematical description and the absence of procedures that allow one to obtain optimal control laws. These problems are due to the presence of links with a pure delay, non-additive random drift, and difficulties in controlling the process parameters, in particular, accurately determining the temperature profile along the horizons and the periphery of the working space of the cupola. The proposed conceptual solution for the synthesis of optimal temperature control allows the use of two levels of control: the level controller solves the problem of maintaining the constant height of the idle charge, and the problem of increasing the temperature of cast iron is solved by controlling the air supply to the tuyere box. It is shown that the problem of regulating the upper level of an idle charge can be solved by reducing the model of the regulation process to a typical form, followed by the use of the Pontryagin maximum principle. A procedure for the synthesis of optimal air flow control is proposed, which makes it possible to obtain the temperature regime control law on the basis of experimental industrial studies preceding the synthesis process. This takes into account the time delay between the impact on the object and its reaction, which makes it possible to predict the temperature value one step acharge, equal to the time interval during which the lower surface of the fuel charge reaches the upper surface of the level of the idle charge. A procedure for temperature profile control based on the use of D-optimal plans for selecting sensor installation points is proposed. Due to this, it becomes possible to determine the temperature profile of the cupola according to its horizons and the periphery of the working space of the cupola with maximum accuracy. The proposed synthesis method can be used in iron foundries equipped with cupolas, as it is a tool for studying a real production process, taking into account its specific conditions. This will allow developing or improving control systems for cupola melting, implementing different control modes: manual, automated or automati