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For parameter estimation of continuous and discrete distributions, we propose a generalization of the method of moments (MM), where Stein identities are utilized for improved estimation performance. The construction of these Stein-type MM-estimators makes use of a weight function as implied by an appropriate form of the Stein identity. Our general approach as well as potential benefits thereof are first illustrated by the simple example of the exponential distribution. Afterward, we investigate the more sophisticated two-parameter inverse Gaussian distribution and the two-parameter negative-binomial distribution in great detail, together with illustrative real-world data examples. Given an appropriate choice of the respective weight functions, their Stein-MM estimators, which are defined by simple closed-form formulas and allow for closed-form asymptotic computations, exhibit a better performance regarding bias and mean squared error than competing estimators.

Laser Powder Bed Fusion (LPBF) offers possibilities towards a sustainable manufacturing due to high powder material recycling rates or manufacturing of lightweight and topology optimized (TO) components. In order to evaluate sustainability respectively resource consumption, Life Cycle Assessment (LCA) is employed, and a virtual model of the physical LPBF process is developed. For conclusive modeling, however, primary data of resource flows and energy consumption must be known. Especially the influence of topology optimization on the resource consumption in LPBF and on the resulting footprint of manufactured geometries is barely investigated. In the present work, TO approaches on an aerospace component are used to reduce the components volume. Two iterations of the component are built on a commercial LPBF system and primary energy data is measured. A LCA model has been developed to compare the ecological impacts of these iterations. Results indicate that by applying TO, the footprint can be reduced.

A Stein-type characterization of the Lindley distribution is derived. It is shown that if using the generalized derivative in the sense of distributions, one can choose all indicator functions as the characterization functions class. This extends some known recent results about characterizations of the Lindley distribution. In addition, a new characterization based on another independent exponential random variable is also provided. As an application of the novel results, some moment formulas related to the Lindley distribution are obtained. Furthermore, generalized method-of-moments estimators for both the discrete and continuous Lindley distribution are proposed, which lead to a notably lower bias at the cost of an only modest increase in mean squared error compared to existing estimators. It is also demonstrated how the Stein characterization might be used to construct a goodness-of-fit test with respect to the null hypothesis of the Lindley distribution. The paper concludes with an illustrative real-data example. [ABSTRACT FROM AUTHOR]

AbstractQualitative, more specifically, ordinal data generating processes are common in real-world process control implementations. In this study, a survey of control charts for the sample-based monitoring of independent and identically distributed ordinal data is provided together with critical comparisons of the control statistics, for memory-less Shewhart-type and for memory-utilizing exponentially weighted moving average (EWMA) and cumulative-sum types of control charts. New results and proposals are also provided for process monitoring. Using some real-world quality scenarios from the literature, a simulation study for performance comparisons is conducted, covering sixteen different types of control chart. It is shown that demerit-type charts used in combination with EWMA smoothing generally perform better than the other charts, which may rely on quite sophisticated derivations. A real-world data example for monitoring flashes in electric toothbrush manufacturing is discussed to illustrate the application and interpretation of the control charts in the study.

For a probability measure μon [0, 1] without discrete component, the best possible order of approximation by a finite point set in terms of the star-discrepancy is &inline as has been proven relatively recently. However, if μcontains a discrete component no non-trivial lower bound holds in general because it is straightforward to construct examples without any approximation error in this case. This might explain, why the approximation of discrete measures on [0, 1] by finite point sets has so far not been completely covered in the existing literature. In this note, we close the gap by giving a complete description for discrete measures. Most importantly, we prove that for any discrete measures (not supported on one point only) the best possible order of approximation is for infinitely many Nbounded from below by &inline for some constant 6 ≥ c>2 which depends on the measure. This implies, that for a finitely supported discrete measure on [0, 1]dthe known possible order of approximation &inline is indeed the optimal one.

In this short note, we reformulate the task of calculating the pair correlation statistics of a Kronecker sequence as a lattice point counting problem. This can be done analogously to the lattice based approach which was used to (re-)prove the famous three gap property for Kronecker sequences. We show that recently developed lattice point counting techniques can then be applied to derive that a certain class of Kronecker sequences have β-pair correlations for all 0<β<1.

For important count distributions, such as (zero-inflated) Poisson and (negative-)binomial, the k th factorial moment is proportional to the k th power of the mean. This property is utilized to derive a general approach for computing higher-order moments of integer-valued generalized autoregressive conditional heteroscedasticity (INGARCH) processes. The proposed approach covers a wide range of existing model specifications, and its potential benefits are illustrated by an analysis of skewness and excess kurtosis in INGARCH processes. [ABSTRACT FROM AUTHOR]

Hintergrund: Die Standardbehandlung des muskelinvasiven Harnblasenkarzinoms ist die Zystektomie mit pelviner Lymphadenektomie. Die primär organerhaltende, trimodale Therapie gilt als Alternative zur radikalen Operation. Fragestellung: Konzept und Ergebnisse der trimodalen Therapie, bestehend aus initialer transurethraler Resektion des Blasentumors (TUR-BT), gefolgt von der simultanen Radiochemotherapie (RCT), werden vorgestellt. Material und Methoden: Es erfolgte eine Auswertung retrospektiver Fallserien und prospektiver Therapieoptimierungsstudien zu primär organerhaltenden Behandlungskonzepten. Komparative Metaanalysen zum Vergleich der Zystektomie mit der trimodalen Behandlung werden vorgestellt. Ergebnisse: Eine komplette TUR-BT samt Blasenmapping und Tumorgrundbiopsie sollte vor RCT angestrebt werden. Die Radiosensibilisierung sollte mit einer cisplatinbasierten Chemotherapie oder mit einer Kombination aus 5‑Fluorouracil und Mitomycin C erfolgen. Komplette Remissionsraten nach TUR-BT plus RCT werden stadienabhängig von 60–90 % der Patienten sowie 5‑Jahres-Überlebensraten von 40–75 % der Patienten mit einem Erhalt der Blase bei etwa 80 % der überlebenden Patienten erreicht. Schlussfolgerungen: Die trimodale Therapie stellt eine gesicherte Alternative zur radikalen Zystektomie mit kurativer Zielsetzung für Patienten mit muskelinvasivem Harnblasenkarzinom dar. Besonders eignen sich Patienten mit frühen Tumoren (cT2/3N0), bei denen die initial TUR-BT zur möglichst kompletten Tumorentfernung (R0) führt. Auch ältere Patienten profitieren von diesem Ansatz.

Powder bed fusion (PBF) is the most commonly adopted additive manufacturing process for fabricating complex metal parts via the layer-wise melting of a powder bed using a laser beam. However, the qualification of PBF-manufactured parts remains challenging and expensive, thereby limiting the broader industrialization of the technology. Powder characteristics significantly influence part properties, and understanding the influencing factors contributes to effective quality standards for PBF. In this study, the influence of the particle size distribution (PSD) median and width on powder flowability and part properties is investigated. Seven gas-atomized SS316L powders with monomodal PSDs, a median particle size ranging from 10 μm to 60 μm, and a distribution width of 15 μm and 30 μm were analyzed and subsequently processed. The PBF-manufactured parts were analyzed in terms of density and melt pool dimensions. Although powder flowability was inversely related to the median particle size, it was unrelated to the distribution width. An inverse relationship between the median particle size and the part density was observed; however, no link was found to the distribution width. Likely, the melt pool depth and width fluctuation significantly influence the part density. The melt pool depth decreases and the width fluctuation increases with an increasing median particle size.

In the Laser Powder Bed Fusion (LPBF) process, parts are built out of metal powder material by exposure of a laser beam. During handling operations of the powder material, several influencing factors can affect the properties of the powder material and therefore directly influence the processability during manufacturing. Contamination by moisture due to handling operations is one of the most critical aspects of powder quality. In order to investigate the influences of powder humidity on LPBF processing, four materials (AlSi10Mg, Ti6Al4V, 316L and IN718) are chosen for this study. The powder material is artificially humidified, subsequently characterized, manufactured into cubic samples in a miniaturized process chamber and analyzed for their relative density. The results indicate that the processability and reproducibility of parts made of AlSi10Mg and Ti6Al4V are susceptible to humidity, while IN718 and 316L are barely influenced.

We provide an algorithm to approximate a finitely supported discrete measure μby a measure νNcorresponding to a set of Npoints so that the total variation between μand νNhas an upper bound. As a consequence if μis a (finite or infinitely supported) discrete probability measure on [0, 1]d with a sufficient decay rate on the weights of each point, then μcan be approximated by νNwith total variation, and hence star-discrepancy, bounded above by (log N)N−1. Our result improves, in the discrete case, recent work by Aistleitner, Bilyk, and Nikolov who show that for any normalized Borel measure μ, there exist finite sets whose star-discrepancy with respect to μis at most (logN)d−12N−1{\left( {\log \,N} \right)^{d - {1 \over 2}}}{N^{ - 1}}. Moreover, we close a gap in the literature for discrepancy in the case d=1 showing both that Lebesgue is indeed the hardest measure to approximate by finite sets and also that all measures without discrete components have the same order of discrepancy as the Lebesgue measure.

Multiplicative error models (MEMs) are commonly used for real-valued time series, but they cannot be applied to discrete-valued count time series as the involved multiplication would not preserve the integer nature of the data. Thus, the concept of a multiplicative operator for counts is proposed (as well as several specific instances thereof), which are then used to develop a kind of MEMs for count time series (CMEMs). If equipped with a linear conditional mean, the resulting CMEMs are closely related to the class of so-called integer-valued generalized autoregressive conditional heteroscedasticity (INGARCH) models and might be used as a semi-parametric extension thereof. Important stochastic properties of different types of INGARCH-CMEM as well as relevant estimation approaches are derived, namely types of quasi-maximum likelihood and weighted least squares estimation. The performance and application are demonstrated with simulations as well as with two real-world data examples. [ABSTRACT FROM AUTHOR]

We propose an effectively nonparametric approach to fitting hidden Markov models to time series of counts, where the state-dependent distributions are estimated in a completely data-driven way without the need to specify a parametric family of distributions. To avoid overfitting, a roughness penalty based on higher-order differences between adjacent count probabilities is added to the likelihood, which is demonstrated to produce smooth state-dependent probability mass functions. The feasibility of the suggested approach is assessed in simulation experiments, and further illustrated in two real-data applications, where we model the distributions of (i) major earthquake counts and (ii) acceleration counts of an oceanic whitetip shark (Carcharhinus longimanus) over time. The proposed methodology is implemented in the accompanying R package countHMM, which is available on CRAN.

Also in a time series context, the simple Poisson distribution is very popular for modeling the marginal distribution of the generated counts. If, in contrast, a more complex count distribution is appropriate, then it is important to have tests available to detect this deviation from Poissonity. A possible approach is to use Fisher’s index of dispersion as a test statistic. For several types of Poisson INARMA process, the generated counts $$X_t$$ Xt do not only exhibit a marginal Poisson distribution, the lagged pairs $$(X_t,X_{t-k})$$ (Xt,Xt-k) are even bivariately Poisson distributed. So to uncover violations of the Poisson null hypothesis within these INARMA processes, the application of a bivariate dispersion index appears to be a reasonable alternative to the simple univariate Fisher index. We survey several proposals for bivariate dispersion indexes and adapt them to a time series context. For the resulting modified indexes, we derive the asymptotic distribution under the null such that they can be used as test statistics. With simulations, we investigate the finite-sample performance of the asymptotic tests, and we analyze the question if the novel tests are advantageous compared to the simple univariate dispersion index test.

Abstract The Average Run Length (ARL) performance of a control chart conditional on parameter estimates from a Phase I study may deviate significantly from its designed performance. To circumvent this problem, the guaranteed conditional performance measure is proposed in the literature. Hence, one does not intend to reach a specified in-control ARL exactly, but to reach an ARL value greater than or equal to a specified in-control ARL with a certain probability. In the literature, the control chart design for a guaranteed conditional performance has only been discussed for the case of independent and identically distributed data. Therefore, a novel guaranteed conditional performance approach for an autocorrelated data generating process is proposed, assuming that the process parameters are unknown. The approach is exemplified by considering an AutoRegressive dependence structure of order 1, i.e., AR(1), and by designing individuals control chart. Appropriate bootstrap schemes are provided for implementation. These bootstrap schemes extend easily from order one to general order p for an AR(p) process. Through simulations, performance analyses of the proposed approach and a study about the robustness with respect to distributional assumptions are provided. [ABSTRACT FROM AUTHOR]

Abstract In this note, we introduce a discrete counterpart of the conventional max-autoregressive moving-average process of Davis and Resnick (1989), based on the binomial thinning operator and driven by a sequence of i. i. d. nonnegative integer-valued random variables with a finite range of counts. Basic probabilistic and statistical properties of this new class of models are discussed in detail, namely the existence of a stationary distribution, and how observations’ and innovations’ distributions are related to each other. Furthermore, parameter estimation is also addressed. [ABSTRACT FROM AUTHOR]

This paper addresses the question whether the LS-sequences constructed in [Car12] yield indeed a new family of low-discrepancy sequences. While it is well known that the case S= 0 corresponds to van der Corput sequences, we prove here that the case S= 1 can be traced back to symmetrized Kronecker sequences and moreover that for S ≥2 none of these two types occurs anymore. In addition, our approach allows for an improved discrepancy bound for S= 1 and Larbitrary.

An interactive computer model was developed to determine the long-term health outcomes and economic consequences of different diabetes management, complication screening and treatment strategies in different subgroups of Type 1 [...]

The cost-effectiveness of intensive versus conventional therapy for type I diabetes was assessed in sub-groups of patients, based on age, race, gender, duration of diabetes, existing diabetic complications, and known [...]

Angiotensin converting enzyme inhibitors (ACE) reduce progression of diabetic renal disease, but have been associated with a 2 - 4 fold increase in risk of severe hypoglycemic events (hypos). A [...]

Intensive insulin therapy decreases the incidence of diabetic microvascular complications, with the disadvantage of a three-fold increase in risk of severe hypoglycemic events. A simulation model was developed to quantify [...]

We propose a compressed sampling and dictionary learning framework for fiber-optic sensing using wavelength-tunable lasers. A redundant dictionary is generated from a model for the reflected sensor signal. Imperfect prior knowledge is considered in terms of uncertain local and global parameters. To estimate a sparse representation and the dictionary parameters, we present an alternating minimization algorithm that is equipped with a preprocessing routine to handle dictionary coherence. The support of the obtained sparse signal indicates the reflection delays, which can be used to measure impairments along the sensing fiber. The performance is evaluated by simulations and experimental data for a fiber sensor system with common core architecture.

For Poisson INAR(1) or INARCH(1) count data time series, explicit asymptotic approximations for bias and standard deviation of common moment estimators are derived. Their finite-sample performance is shown by simulations. Bias corrected estimators are applied within examples. [ABSTRACT FROM AUTHOR]

To monitor count-type observations that are correlated over time, the Poisson INAR(1) CUSUM chart has been proposed for cases where an integer-valued autoregressive process of order 1 with a Poisson marginal is appropriate. In a recent study, it is shown that the Poisson INAR(1) CUSUM control chart is especially well suited to detection problems that involve mean shifts in a process. Although special causes of variation that result in mean shifts are the most common out-of-control situations in practice, some special causes of variation may also result in shifts of the autocorrelation coefficient or the process variance. In this research, we define three types of residuals from the time-series model and develop corresponding approaches for CUSUM monitoring. In particular, three CUSUM control charts, one for each of these residuals, as well as a multivariate CUSUM monitoring of the residuals are investigated. A Phase II comparison of these residuals' monitoring approaches together with a benchmark CUSUM of the count type observations indicate that, for different types of process shifts, different residual monitoring approaches may perform better.

Abstract: The compound Poisson INAR(1) model for time series of overdispersed counts is considered. For such CPINAR(1) processes, explicit results are derived for joint moments, for the -step-ahead distribution as well as for the stationary distribution. It is shown that a CPINAR(1) process is strongly mixing with exponentially decreasing weights. This result is utilized to design a test for overdispersion in INAR(1) processes and to derive its asymptotic power function. An application of our results to a real-data example and a study of the finite-sample performance of the test are presented. [Copyright &y& Elsevier]

Abstract: The NDARMA model is a discrete counterpart to the usual ARMA model, which can be applied to purely categorical processes. NDARMA processes are shown to be -mixing, so it is possible to find asymptotic expressions for the distribution of several types of statistics. Such asymptotic properties are useful for hypothesis testing or other inferential procedures. This is exemplified by considering the Gini index and the entropy as measures of marginal dispersion, the Pearson statistic for checking the goodness-of-fit with regard to a hypothetical marginal distribution, and several measures of signed or unsigned serial dependence. For each of these cases, the obtained asymptotic approximations are also compared to the empirically observed behavior in time series of finite length. Practical applications are illustrated by a real-data example. [Copyright &y& Elsevier]

The INARCH(1) model has been proposed in the literature as a simple, but practically relevant, two-parameter model for processes of overdispersed counts with an autoregressive serial dependence structure. In this research, we develop approaches for monitoring INARCH(1) processes for detecting shifts in the process parameters. Several cumulative sum control charts are derived directly from the log-likelihood ratios for various types of shifts in the INARCH(1) model parameters. We define zero-state (worst-state) and steady-state average run length metrics and discuss their computation for the proposed charts. An extensive study indicates that these charts perform well in detecting changes in the process. A real-data example of strike counts is used to illustrate process monitoring.

Abstract: The INARCH(1) model is a simple but practically relevant, two-parameter model for processes of overdispersed counts with an autoregressive serial dependence structure. We derive closed-form expressions for the joint (central) moments and cumulants of the INARCH(1) model up to order 4. These expressions are applied to derive the moments of jumps in INARCH(1) processes. We illustrate this kind of application with a real-data example, and outline further potential applications. [ABSTRACT FROM AUTHOR]

This work presents a new record of a paleolake in the Yemeni Highlands. The sedimentary record shows a fast development of a permanent water body with diatoms and freshwater gastropods revealing environmental conditions of a shallow, eutrophic water body. During younger (earlier) stages of sedimentation, the sediments show a slow decrease of humidity (rain) with dry interruptions (arid conditions). Stable isotope data of gastropods evidence this development, in lower parts of the profile, they have negative values for d18O, in the upper parts the values show a large variation with positive values corresponding with changing conditions in the sedimentary environment. Prehistoric settlements around the lake deposits suggest that men profited from this special environment.

Calcareous tufas can be found frequently in small streams in the Frankonian Alb and are linked to the Karst. Sample bodies of different material were placed in one of the tufa cascades for one year and were constantly changed. The accumulated carbonate on these sample bodies was analysed. The intention was to identify the carbonate sedimentation rate without the influence of porosity and the thickness of lamination. During the year the carbonate formation shows immense differences. In the winter time the amounts ranges from 0,005 to 0,02 g/25 cm2 and in the summer they reach up to 0,18g/25 cm2.

Abstract: We consider the binomial AR(1) model for serially dependent processes of binomial counts. After a review of its definition and known properties, we investigate marginal and serial properties of jumps in such processes. Based on these results, we propose the jumps control chart for monitoring a binomial AR(1) process. We show how to evaluate the performance of this control chart and give design recommendations. [Copyright &y& Elsevier]

Attributes control charts for counts generally assume that the process being monitored is independent and identically distributed in its in-control state. However, violation of this assumption in practice may significantly degrade a chart's performance and usefulness if the autocorrelation structure is not taken into account. To describe the autocorrelation structure of counts in an in-control process, integer-valued autoregressive moving average process models can be employed. This paper investigates the cumulative sum (CUSUM) control chart for monitoring autocorrelated processes of counts modeled by a Poisson integer-valued autoregressive model of order 1, namely Poisson INAR(1). The CUSUM chart is designed to detect assignable causes affecting the process mean, but also changes in the autocorrelation structure are considered. Exact numerical results obtained through a bivariate Markov chain approach are provided for sustained shifts in any or both of these process parameters. Some numerical results from a simulation study of the residuals' monitoring are also presented. It is shown that the considered CUSUM chart of observations has good overall performance in detecting assignable causes in autocorrelated count processes.

Abstract: Qadhat is the name for a lime mortar in Southern Arabia. Its usage has a long tradition. This work describes physical and mineralogical properties of ancient, historical and new samples, which seem to have been produced the same way. XRD, thin sections and SEM analyses show the similarity of the material. It consists of aggregates of volcanic material that are rich in volcanic glass and lime as binder. The production process includes several hours of crushing the material, which produces fine-grained splinters of aggregates in the binder matrix and gives the mortar a high stability. A weathering test with sodium sulphate on different samples confirms that the stability of this mortar is the result of the production process.

Abstract: A new AR() model for time series of counts is investigated, the possible marginal distributions of which are those of the DSD family. We determine the autocorrelation structure of the whole model family and analyze two important special cases. A real-data example demonstrates the practical relevance of the new model family. [Copyright &y& Elsevier]

Abstract: The detection of patterns in categorical time series data is an important task in many fields of science. Several efficient algorithms for finding frequent sequential patterns have been proposed. An online-approach for sequential pattern analysis based on transforming the categorical alphabet to real vectors and generating fractals by an iterated function systems (IFS) is suggested. Sequential patterns can be analyzed with standard methods of cluster analysis using this approach. A version of the procedure allows detecting patterns visually. [Copyright &y& Elsevier]

Miocene limnic and pedogene carbonates are known from different places in the Franconian Alb. Some of them are fresh water carbonates deposited in small lakes or rivers. Some are terrestrial caliche carbonates moulded in soils. The work describes carbonates near to Langenaltheim/Southern Frankonian Alb. This carbonates occur only on a small site, on a field without outcrop. The stones are deposited in a freshwater environment. The facies is a polymictic conglomerate, which contains onkolites, gastropods, peloids and pisoids. The facies of the nucleus of the oncolites is a pedogene and lacustrine facies and shows that during the Miocene different lakes and terrestrial environments existed for the building of carbonate rocks. The components within the oncoid nucleus suggest various environments for carbonate building depending on the water level below and above the soil-surface.

GermanDer Almaqah-Tempel in der antiken Stadtanlage von Sirwah (Jemen) war ein zentrales Heiligtum der sabäischen Kultur. Er wurde über mehrere Jahrhunderte als Kultstätte genutzt (ca. 9. Jh. v. Chr. bis 6. Jh. n. Chr.) und im 19. Jahrhundert als Wohnanlage überbaut. Schwerpunkte der Anlage sind der Eingang mit sechs monolithischen Pfeilern, drei überdimensionale Inschriftensteine des 1. Jt. v. Chr. mit 49 m durchgehendem Text sowie Altäre, Schatzkammer, Bankettbereich und mehrere Brunnen. Als Baumaterial wurden fast ausschließlich Kalke des Oberen Jura (Amran-Gruppe) verwendet, die in unmittelbarer Umgebung (400 m hohe Steilstufe) anstehen. Zahlreiche meist kleinere Steinbrüche wurden in bestimmten Schichten gefunden. Die Kalke weisen am Bauwerk zum Teil intensive Schäden auf.In den Jura-Kalken (Oxford–Tithon ?) konnten bisher sieben regressive Sequenzen von basalen Knollenkalken über Kalk-Mergel-Wechselfolgen zu mächtigen (bis 9 m) massigen Dachbank-Schichten festgestellt werden. Die biostratigraphische Gliederung erfolgt mittels Foraminiferen, Dasycladaceen und Nerineen. Überwiegend kleine (Dezimeter bis Meter), in Mergel eingebettete ,,Patch"-Riffe (Stromatoporen, Austern, Korallen) können aber auch eine laterale Ausdehnung bis zu 50 m haben. Die Folge entwickelt sich zyklisch von Mudstones über MolluskenWackestones, Dasycladaceen-Wackestones, Stromatoporen- und Korallen-Boundstones, Peloid-Packstones zu Ooid-Onkoid-Grainstones und wird von quarzreichen, teilweise dolomitisierten Mergelsteinen überlagert.Die am Tempel verbauten Kalksteine können in fünf Mikrofaziestypen untergliedert werden: Mudstones (MFT-1), Wacke- und Packstones mit Foraminiferen, Algen, Peloiden und Onkoiden (MFT-2), Pack-, Grainstones und Rudstones (MFT-3) mit Gastropoden, Bivalven, Echinodermaten und Korallen, Ooid-Pack- und Grainstones (MFT-4) und ein diagenetisch besonders überprägter Fossilschuttkalk (Echinodermen-Molluskenschill, Grainstone, MFT-5). Die Kalksteine wurden überwiegend gemäß ihrer Qualität (Faziestyp) für unterschiedliche Gebäudeelemente genutzt (Bodenplatten = Mudstones und Wackestones, Mauern = Wackestones und Packstones, Bankett = Wackestones und Packstones, Pfeiler und Inschriftensteine = Packstones und Grainstones.Es können fünf Schadensklassen festgestellt werden, die von (1) leichtem Ausbrechen an Kanten und Aufrauen der Oberfläche über flächige Rückverwitterung (3) bis hin zur (5) völligen Zerstörung der Oberfläche und Gesteinszerfall reichen. Dabei sind Porosität und Porengeometrie sowie die Matrixgehalte von besonderer Bedeutung für die Verwitterungsstabilität; sie steuern den Feuchtehaushalt (Trocknungsverhalten, hygrische Dehnung) der Kalksteine. Wacke- und Packstones zeigen Materialverlust durch kleinflächiges Abschalen sowie Aufwittern entlang von Rissen und Stylolithen als typische Verwitterungsformen. Das Auswittern von Komponenten ist charakteristisch für Pack-, Grain- oder Rudstones. Intensiver Materialverlust durch oberflächiges Abschalen tritt vor allem in Bereichen mit hoher Salzkontamination (Nitrate und Chloride) und starker anthropogener Belastung auf (ehemalige Wohnräume und Stallungen in islamischer Zeit). Exponierte Steine, wie an der Außenwand des Tempels, zeigen nur eine leichte Patina mit geringer Rückverwitterung.Zur Feststellung eventueller Zusammenhängen zwischen Faziestyp und Schadensklasse wurden Kenndaten (Porosität, Porenradienverteilung, Wasseraufnahme, Trocknungsverhalten) und Salzverteilung in der Fläche und in Tiefenprofilen analysiert. Es zeigt sich, dass in Bereichen mit lokal hohem anthropogenem Eintrag (Stallung) die durch Salz bedingten Schäden die auf die Faziestypen und deren unterschiedliche Verwitterungsstabilität zurückzuführenden Schäden bei weitem überlagern.Die Verwitterungsbilder der am Tempel verwendeten Kalksteine entstehen durch das Zusammenspiel mehrerer Faktoren. Die hohe Salzkontamination und anthropogene Schäden (Stallung, Brand, Umbau) intensivieren die natürliche Verwitterung und sorgen an Gebäudeteilen, die einer langen anthropogenen Nutzung unterlagen, für schwere Schäden. Durch das Abtragen der Sedimentbedeckung wurde zwar die direkte Ursache der Salzkontamination beseitigt, aber es wurden auch neue Transportsysteme eröffnet, die nun bei einer mögliche Salzreduzierung und bei den restauratorischen Maßnahmen berücksichtigt werden müssen. AbstractThe Almaqah Temple of the antique township of Sirwah (Yemen) was one of the main sacral buildings in Sabaean times (9th century B.C. – 6th century A.D.) and overbuilt in the 19th century by a settling place. Topics of the monument are an entrance with six columns, three inscription stones with 49 m text as well as altars, treasury, banquet, and wells. Limestones of the Amran Group (Upper Jurassic) which crop out nearby in a 400 m thick section were used as building stones. Many small quarries occur in different stratigraphic levels.Seven regressive cycles can be analyzed in the Upper Jurassic sequence (Oxford–Tithon?). A cyclic development from nodular limestones to limestone-marl-alternations to thick massive top beds (up to 9 m) is obvious. In general a microfacies development from bottom to top can be recognized (mudstone, mollusc-wackestones, dasycladacean-wackestone, stromatoporoid- and coral boundstone, ooid-oncoid-grainstone; topped by quartz-rich dolomitic marls). The biostratigraphic subdivision is based on foraminifera, dasycladaceans, and nerinean-gastropods. Small patch-reefs (up to meter) occur in the marls and can also reach up to 50 m lateral extension.The limestones used can be subdivided in five microfacies-types (MFT-1 = mudstone, MFT-2 = wacke- and packstones with foraminifera, algae, peloids, and oncoids, MFT-3 = pack-, grainstone and rudstone with gastropods, bivalves, echinoids and corals, MFT-4 = ooid-pack- and grainstones, and MFT-5 = grainstone, a diagenetic overprinted highly porous debris limestone with echinoids and molluscs). The limestones were used according to their quality (weathering resistance, facies type) for varying parts of the building (flagstones = mudstones and wackestones, walls = wackestones and packstones, banquet = wackestones and packstones, columns and inscription stones = packstones and grainstones).Damages can be subdivided in five classes. Porosity and pore geometry as well as the matrix content are of main importance for the weathering stability because they trigger the moisture content, the hygric expansion, and the drying of the stones. Wackestones and packstones reveal loss of material by small flakes and weathering along stylolites and fractures. The sanding of particles is characteristic for pack- and grainstones. Most intensive decay by loss of larger plates on surfaces is recognized in areas of high contamination by salt (nitrates and chlorides) and intensive anthropogenic use (living rooms, stables) in Islam times. Outside exposed stones on the walls only reveal thin crusts and minor weathering.For a possible correlation between facies types and damage characteristics data were analyzed (porosity, pore throat diameter, water uptake, drying) and the distribution of salts on the surface and in profiles. It can be shown that in areas of high contamination intensive damages caused by salt are overprinting damages which are related to weathering stability of facies-types. The weathering of the limestones is caused by the interaction of varying factors. The local high contamination with salt and anthropogenic damages (stables, fire, dismantling) intensify the natural weathering which predominantly is depending on facies types. Due to the excavation the sediment cover was taken away. Thus the source for many salts disappeared but new mechanisms of redistribution were opened. This has to be taken into account for the restoration of intensively damaged zones with high salt contamination.

Apoptosis can be induced by distinct but overlapping pathways. Ionizing radiation induces apoptosis by an “intrinsic”, mitochondria-dependent pathway. Ligation of tumor necrosis factor-(TNF-)α, FAS (CD95) or TRAIL receptors are typical representatives of an extrinsic, death-receptor-mediated pathway. In this study the effect of irradiation, treatment with the cytokine TNF-α, or a combination of both on the induction of apoptosis and clonogenic survival of bladder carcinoma cells was investigated. 5637 bladder carcinoma cells were treated with different concentrations of recombinant TNF-α (0–10 ng/ml), irradiated with single doses ranging from 0.5 to 10 Gy, or a combination of both modalities. Apoptotic cells were quantified by the TUNEL assay up to 96 h following treatment, clonogenic cell survival by a clonogenic assay. Synergistic effects of both modalities were evaluated using isobolographic analysis. Irradiation of 5637 carcinoma cells resulted in a discontinuous dose dependence of the apoptotic fraction with a pronounced increase in the range of 0–2 Gy and a slighter increase at 2–10 Gy. The percentage of apoptotic carcinoma cells also increased continuously after treatment with lower concentrations of TNF-α reaching a plateau at concentrations of 5.0–10.0 ng/ml. Isobolographic analysis revealed a supraadditive interrelationship between irradiation and TNF-α in the range between 0.005 and 0.5 ng/ml, and an additive effect for TNF-α concentrations > 0.5 ng/ml. The additive effects were confirmed in clonogenic survival assays with reduced survival fractions following combined TNF-α administration and irradiation. The combination of two apoptosis-inducing modalities resulted in a synergistic effect on the induction of apoptosis in 5637 bladder carcinoma cells. Although a radiosensitizing effect still has to be proven in animal models, combined-modality treatment may increase the therapeutic effectiveness of irradiation in bladder cancer. Apoptose kann durch unterschiedliche, teilweise überlappende Reaktionswege induziert werden. Während ionisierende Strahlung Apoptose über eine intrinsische, mitochondrienabhängige Reaktionskaskade vermittelt, stellen die Aktivierung von Tumor-Nekrose-Faktor-(TNF-)α, FAS-(CD95-) oder TRAIL-Rezeptoren typische Beispiele der extrinsischen, „Todesrezeptor“-vermittelten Induktionskaskade dar. In dieser Studie wurde der Effekt einer Bestrahlung, der Gabe des Zytokins TNF-α oder einer kombinierten Therapie auf die Apoptoserate bzw. das klonogene Überleben einer Blasenkarzinomzelllinie untersucht. 5637-Blasenkarzinomzellen wurden mit unterschiedlichen Konzentrationen von rekombinantem TNF-α (0–10 ng/ml), Bestrahlung mit Dosen von 0,5–10 Gy oder der Kombination aus beiden Modalitäten behandelt. Die Apoptoserate wurde mit dem TUNEL-Assay bis 96 h nach Behandlung bestimmt, das klonogene Überleben in einem Koloniebildungstest. Synergistische Effekte beider Behandlungsmodalitäten wurden in einer isobolographischen Analyse ermittelt. Die alleinige Bestrahlung der 5637-Karzinomzellen wies eine diskontinuierliche Dosisabhängigkeit der Apoptoseinduktion mit einem steileren Anstieg im Dosisbereich von 0–2 Gy und einer geringeren Steigerung im Bereich von 2–10 Gy auf. Der Anteil apoptotischer Karzinomzellen stieg nach Behandlung mit geringeren Dosen von TNF-α kontinuierlich an und erreichte ein Plateau bei Konzentrationen von 5,0–10,0 ng/ml. Die isobolographische Analyse zeigte für die Kombination von Bestrahlung und TNF-α im Konzentrationsbereich von 0,005–0,5 ng/ml einen supraadditiven Effekt und einen additiven für TNF-α-Konzentrationen > 0,5 ng/ml. Diese additiven Effekte wurden im Koloniebildungstest durch verminderte Überlebensfraktionen nach TNF-α- Gabe und Bestrahlung bestätigt. Die Kombination zweier apoptoseinduzierender Modalitäten zeigte einen synergistischen Effekt auf die Induktion der Apoptose und Minderung des Zellüberlebens in 5637-Karzinomzellen. Obwohl eine strahlensensibilisierende Wirkung noch in Tiermodellen überprüft werden muss, könnte die Kombinationstherapie die therapeutische Effektivität einer Bestrahlung des Blasenkarzinoms steigern.