An efficient Algorithm to partition a Sequence of Integers into Subsets with equal Sums

To partition a sequence of n integers into subsets with prescribed sums is an NP-hard problem in general. In this paper we present an efficient solution for the homogeneous version of this problem; i.e. where the elements in each subset add up to the same sum.Comment: 12 page

Effiziente Lösungen von Spezialfällen des Cutting sticks-Problems

Das Cutting sticks-Problem ist in seiner allgemeinen Formulierung ein NP-vollständiges Problem mit Anwendungspotenzialen im Bereich der Logistik. Unter der Annahme, dass P ungleich NP (P != NP) ist, existieren keine effizienten, d.h. polynomiellen Algorithmen zur Lösung des allgemeinen Problems. In diesem Papier werden für eine Reihe von Instanzen effiziente Lösungen angegeben

Molecular Analysis of the Autosomal Dominant Spastic Paraplegia Type IV (SPG4)

Reine hereditäre spastische Paraplegie (pHSP) bezeichnet eine Gruppe von relativ gutartigen neurodegenerativen Erkrankungen des Rückenmarks. Das hervorstechende klinische Symptom ist eine langsam fortschreitende Gang-Anomalität, die durch eine Spastik der Beine begründet ist. Autosomal dominante hereditäre spastische Paraplegien (ADHSP) sind die Hauptformen von pHSP und sind genetisch heterogen. Als Genorte für die reine ADHSP wurden die Chromosomen 2 (SPG4 auf 2p 21-24, SPG13 auf 2q24-34), 8 (SPG8 auf 8q23-24), 12 (SPG10 auf 12p13), 14 (SPG3 auf 14q11.2-q24.3), 15 (SPG6 auf 15q11.1), und 19 (SPG12 auf 19q13) identifiziert. Bis zum heutigen Tag wurde allein das in SPG4-Patienten mutierte SPAST-Gen kloniert und analysiert. Die Ziele dieser Dissertation sind: (1) Bestimmung des Krankheitslocus einer großen Familie mit reiner ADHSP; (2) Erstellung einer physikalischen Karte der Kandidaten-Gen-Region, um Kandidaten-Gene untersuchen zu können; (3) Untersuchung, ob CAG-Repeat-Expansionen für die Krankheitsentwicklung verantwortlich sind und (4) Suche nach neuen Mutationen im SPAST-Gen.Pure hereditary spastic paraplegias (pHSP) are relatively mild neurodegenerative disorders of the spinal cord. The predominant clinical sign is a slowly progressive gait anomaly due to spasticity of the legs. Age of onset is usually during adulthood, but varies greatly both within and between families. Autosomal dominant hereditary spastic paraplegia (ADHSP) are the major forms of pHSP and are genetically heterogeneous. The disease loci of pure ADHSP have been assigned to chromosomes 2 (SPG4 in 2p 21-24, SPG13 in 2q24-34), 8 (SPG8 in 8q23-24), 12 (SPG10 in 12p13), 14 (SPG3 in 14q11.2-q24.3), 15 (SPG6 in 15q11.1), and 19 (SPG12 in 19q13). To date, the SPG4 gene SPAST has been identified. This dissertation included (1) the determination the disease locus of a large family with pure ADHSP, (2) the construction the physical map of the candidate region as the first step to identify the disease gene, (3) the investigation of whether CAG repeat expansions were involved in the mechanism of disease, and (4) the screenings the mutation of patients with the SPAST gene

Ein Bezugsrahmen für Rollen in Unternehmungen. Teil 1: Grundlagen, Abgrenzung und Methodik

In an operational environment every employee has to fulfill a role which he or she is obliged to execute depending on largely objective guidelines like the affiliation of an enterprise to a certain type, sector and life cycle. There is only little scope left for subjective preferences and resentments. The pragmatic research objective is to design a framework to identify the information requirements of different roles. Our goal is to back the decisions an employee has to make by providing a personalized set of information and recommending useful methods. To do so, at first this paper gives an overview on existing role concepts. On their basis an integrated model is subsequently developed and described.Im betrieblichen Kontext nimmt der einzelne Arbeitnehmer eine Rolle ein, die er abhängig von weit gehend objektiven Vorgaben (z. B. Arbeitsplatzbeschreibungen, Gesetzesvorschriften) ausführen muss und die nur teilweise Spielraum für (subjektive) Vorlieben und Abneigungen lässt. Die Rolle wiederum wird durch den Betriebstyp, die Branche und die Lebensphase des Unternehmens (z. B. Gründung, Restrukturierung, Internationalisierung, Sanierung) bestimmt. Es besteht die Gefahr, dass die verschiedenen Sichten völlig unabhängig voneinander und damit sehr unsystematisch entwickelt werden, weil ein Bezugsrahmen (Framework) fehlt. Dieser Bericht gibt als Erstes einen Überblick über bekannte Rollenkonzepte. Auf deren Basis wird anschließend ein integratives Modell entworfen und beschrieben

Определение технических характеристик размешивания и проектирование оборудования для вязких сред

Существенным недостатком подходов у многих исследователей является большое количество упрощений расчетных моделей и невозможность точной количественной оценки параметров технологического процесса перемешивания. В данной работе, эффективность перемешивания трех видов импеллеров была исследована. Все расчеты и анализы были проведены с помощью не только физических моделей но и Ansys v17.2, что обеспечил качество результата данного исследования.In this study computational fluid dynamics (CFD) approach was used to study mixing in an Industrial tank. We use Ansys v17.2 to do the evaluation of fluid mixing efficiency. In this study we use three different mixer models to do the comparison. The objective was to analyze the extent of mixing in the tank by producing visual images of the various mixing zones in the tank domain

Исследование оптических свойств реконденсатов CCl4, полученных методом криоматричной изоляции

Объектом исследования являются тетрахлорметаан (четырёххлористый углерод) CCl4, которые были получены методом газофазной конденсации с матричным газом в различных концентрационных соотношениях с азотом и аргоном. Целью работы является изучение процессов формирования и эволюции свойств тонких пленок реконденсатов молекул фреона CCl4, образующихся в результате структурно-фазовых превращений и релаксационных процессов в твердых растворах исследуемых веществ при низких и сверхнизких температурах. Для достижения, были поставлены такие задачи: определить взаимосвязь между условиями криоосаждения и свойствами образующейся криоконденсированной пленки, а также изучить особенности криоконденсации тетрахлорометана и определить температуру стеклования образованных при низких температурах криопленок.The object of the study is carbon tetrachloride, which were obtained by gas-phase condensation with matrix gas in various concentration ratios with nitrogen and argon. The aim of the work is to study the processes of formation and evolution of the properties of thin films of recondensates of CCl4 freon molecules formed as a result of structural-phase transformations and relaxation processes in solid solutions of the studied substances at low and ultra-low temperatures. To achieve this, the following tasks were set: to determine the relationship between the conditions of cryopreservation and the properties of the resulting cryocondensated film, as well as to study the features of cryocondensation of tetrachloromethane and to determine the glass transition temperature of cryofilms formed

Rekombinante Biosynthese amino-substituierter Phenylpropanoide in E. coli

Aromatic compounds and olefins are important precursors for chemical syntheses. The main source for these substances are the refining processes of crude oil. Driven by political, economical and ecological reasons the research in crude oil alternatives and therefore the utilisation of renewable resources gained particular importance. The objective is the biotechnological and chemical generation of adequate substitutes for important compounds but also of other substances that are currently only inefficiently synthesised. The recombinant biosynthesis of amino-substituted phenylpropanoids in E. coli aims at the production of p-aminocinnamyl alcohol. This aromatic alcohol is a novel compound with several functional groups and it has significant similarity to the naturally occurring monolignol p-coumaryl alcohol. Unlike this substance there is no existing pathway known for the biosynthesis of the derivate in natura. The approach to design an artificial pathway for p-aminocinnamyl alcohol is based on the combination of different reactions from the biosynthetic pathways for chloramphenicol, phenylpropanoids and lignin. It was shown that genetically modified E. coli cells can synthesise p-aminophenylalanine from endogenously available chorismate by using 4-amino-4-deoxychorismate synthase from Corynebacterium glutamicum and Streptomyces venezuelae 4-amino-4-deoxychorismate mutase and 4-amino-4-deoxyprephenate dehydrogenase. The uncommon, non-proteinogenic amino acid can undergo reactions of phenylpropanoid and lignin biosynthesis alike the natural substrate tyrosine. The deamination by Rhodobacter sphaeroides tyrosine ammonia-lyase or Zea mays phenylalanine ammonia-lyase to p-aminocinnamic acid is followed by the coenzyme A mediated activation by 4-coumarate:CoA ligase (Petroselinum crispum). p-Aminocinnamyl-CoA is a substrate for Zea mays cinnamyl-CoA reductase and the resulting aldehyde is converted by Zea mays cinnamyl alcohol dehydrogenase to the target product. Subsequently it is exported into the culture medium. Additionally, a short cut was identified that – simply by the activity of CoA ligase and reductase – efficiently converts the acid into the alcohol. All seven transgenes were functionally expressed in E. coli. It is the simultaneous abundance of all proteins that allows for the biosynthesis of p-aminocinnamyl alcohol without feeding any direct precursors. This demonstrates that complex artificial syntheses can be established by the way of biotechnological methods. The availability of this novel aromate permits new processing such as the polymerisation to novel thermoplasts with so far unknown functions

Rekombinante Biosynthese amino-substituierter Phenylpropanoide in E. coli

Aromatic compounds and olefins are important precursors for chemical syntheses. The main source for these substances are the refining processes of crude oil. Driven by political, economical and ecological reasons the research in crude oil alternatives and therefore the utilisation of renewable resources gained particular importance. The objective is the biotechnological and chemical generation of adequate substitutes for important compounds but also of other substances that are currently only inefficiently synthesised. The recombinant biosynthesis of amino-substituted phenylpropanoids in E. coli aims at the production of p-aminocinnamyl alcohol. This aromatic alcohol is a novel compound with several functional groups and it has significant similarity to the naturally occurring monolignol p-coumaryl alcohol. Unlike this substance there is no existing pathway known for the biosynthesis of the derivate in natura. The approach to design an artificial pathway for p-aminocinnamyl alcohol is based on the combination of different reactions from the biosynthetic pathways for chloramphenicol, phenylpropanoids and lignin. It was shown that genetically modified E. coli cells can synthesise p-aminophenylalanine from endogenously available chorismate by using 4-amino-4-deoxychorismate synthase from Corynebacterium glutamicum and Streptomyces venezuelae 4-amino-4-deoxychorismate mutase and 4-amino-4-deoxyprephenate dehydrogenase. The uncommon, non-proteinogenic amino acid can undergo reactions of phenylpropanoid and lignin biosynthesis alike the natural substrate tyrosine. The deamination by Rhodobacter sphaeroides tyrosine ammonia-lyase or Zea mays phenylalanine ammonia-lyase to p-aminocinnamic acid is followed by the coenzyme A mediated activation by 4-coumarate:CoA ligase (Petroselinum crispum). p-Aminocinnamyl-CoA is a substrate for Zea mays cinnamyl-CoA reductase and the resulting aldehyde is converted by Zea mays cinnamyl alcohol dehydrogenase to the target product. Subsequently it is exported into the culture medium. Additionally, a short cut was identified that – simply by the activity of CoA ligase and reductase – efficiently converts the acid into the alcohol. All seven transgenes were functionally expressed in E. coli. It is the simultaneous abundance of all proteins that allows for the biosynthesis of p-aminocinnamyl alcohol without feeding any direct precursors. This demonstrates that complex artificial syntheses can be established by the way of biotechnological methods. The availability of this novel aromate permits new processing such as the polymerisation to novel thermoplasts with so far unknown functions

Ansätze für effiziente Lösungen von Cutting sticks-Problemen und deren Charakterisierung

Das Cutting sticks-Problem ist in seiner allgemeinen Formulierung ein NP-vollständiges Problem mit Anwendungspotenzialen im Bereich der Logistik. Unter der Annahme, dass P ungleich NP (P != NP) ist, existieren keine effizienten, d.h. polynomiellen Algorithmen zur Lösung des allgemeinen Problems. In diesem Papier werden Ansätze aufgezeigt, mit denen bestimmte Instanzen des Problems effizient berechnet werden können. Für die Berechnung wichtige Parameter werden charakterisiert und deren Beziehung untereinander analysiert