Forms Of Decay Research Articles

Empirical analysis of collective human behavior for extraordinary events in the blogosphere

To uncover an underlying mechanism of collective human dynamics, we survey more than 1.8 billion blog entries and observe the statistical properties of word appearances. We focus on words that show dynamic growth and decay with a tendency to diverge on a certain day. After careful pretreatment and the use of a fitting method, we found power laws generally approximate the functional forms of growth and decay with various exponents values between -0.1 and -2.5. We also observe news words whose frequencies increase suddenly and decay following power laws. In order to explain these dynamics, we propose a simple model of posting blogs involving a keyword, and its validity is checked directly from the data. The model suggests that bloggers are not only responding to the latest number of blogs but also suffering deadline pressure from the divergence day. Our empirical results can be used for predicting the number of blogs in advance and for estimating the period to return to the normal fluctuation level.

Mitigation of Pollution-induced Deterioration of Digital Prints through Low-Temperature Storage

An IPI survey found that approximately 87% of museums, libraries and archives already have digital prints in their collections and that they are concerned about increasing influxes of these materials. The survey also showed that objectionable deterioration has already occurred to some of their prints including fading, yellowing, color bleed, surface cracking and delamination. In total, 71% of institutions have already experienced deterioration in their digital print collections. Previous experimental research, both by IPI and others, has been able to establish a clear connection between ozone and nitrogen dioxide exposure and each of those forms of decay. Development of effective methods to mitigate such damage will, therefore, be critical to the survival of these objects for future generations. This study was aimed specifically at determining the efficacy of one particular approach, mitigating pollutant damage to digital prints through lowered-temperature storage. Since the deterioration due to pollutants occurs through chemical reactions, it may be possible to slow decay through cool or cold storage.The Arrhenius method was used to predict the times to significant fade or yellowing of prints exposed to 1 ppm ozone or 5 ppm nitrogen dioxide. Test targets were incubated at 25°C, 30°C, 35°C, 40°C, and 45°C at 50% RH for multiple intervals up to 56 days. Cyan, magenta, yellow, and black color patches were monitored using ANSI Status A density for density loss. Unprinted, white areas were monitored using ANSI Status A blue density for paper yellowing. It was found that lower temperature does in fact reduce the rates of decay but not equally for both pollutants. Low temperature was more effective at reducing yellowing caused by nitrogen dioxide than it was at reducing the fade caused by ozone; however, cool or cold storage can clearly mitigate damage and extend the usable life of digital prints in collections.

Untreated severe dental decay: a neglected determinant of low Body Mass Index in 12-year-old Filipino children

BackgroundDental decay is the most common childhood disease worldwide and most of the decay remains untreated. In the Philippines caries levels are among the highest in the South East Asian region. Elementary school children suffer from high prevalence of stunting and underweight.The present study aimed to investigate the association between untreated dental decay and Body Mass Index (BMI) among 12-year-old Filipino children.MethodsData collection was part of the National Oral Health Survey, a representative cross-sectional study of 1951 11-13-year-old school children using a modified, stratified cluster sampling design based on population classifications of the Philippine National Statistics Office. Caries was scored according to WHO criteria (1997) and odontogenic infections using the PUFA index. Anthropometric measures were performed by trained nurses. Some socio-economic determinants were included as potential confounding factors.ResultsThe overall prevalence of caries (DMFT + dmft > 0) was 82.3% (95%CI; 80.6%-84.0%). The overall prevalence of odontogenic infections due to caries (PUFA + pufa > 0) was 55.7% (95% CI; 53.5%-57.9%) The BMI of 27.1% (95%CI; 25.1%-29.1%) of children was below normal, 1% (95%CI; 0.5%-1.4%) had a BMI above normal. The regression coefficient between BMI and caries was highly significant (p < 0.001). Children with odontogenic infections (PUFA + pufa > 0) as compared to those without odontogenic infections had an increased risk of a below normal BMI (OR: 1.47; 95% CI: 1.19-1.80).ConclusionsThis is the first-ever representative survey showing a significant association between caries and BMI and particularly between odontogenic infections and below normal BMI. An expanded model of hypothesised associations is presented that includes progressed forms of dental decay as a significant, yet largely neglected determinant of poor child development.

Gypsum-induced decay in granite monuments in Northwestern Spain

One of the most common forms of decay in granite monuments is the detachment of the superficial layer of the stone (plaques, plaquettes and scales). Previous studies of granite monuments in the northwest Iberian Peninsula revealed a direct relation between this type of weathering and the presence of calcium sulphate, and a mechanism whereby the salt causes this type of decay was suggested. In the present study, various hypotheses as regards the origin of the gypsum found in granite monuments are proposed. The study involved analysis of the contents of ions soluble in water, the results of X-ray diffraction analyses and the ratios of CaO/SO 3 in samples of stone, mortar and deposits collected from different monuments. It was concluded that in most cases the gypsum originated from old paintworks or/and from the joint mortars, although inputs from other sources cannot be discounted, as discussed

Decay of the Campanile limestone used as building material in Tudela Cathedral (Navarra, Spain)

Abstract A characterization is presented of the building materials used in the Cathedral of Tudela, as well as of the different forms of decay, with the aim of establishing the cause and mechanisms of this decay. The Cathedral of Tudela was built mainly with Campanile limestone from the upper Miocene. The campanile limestone is a wackestone, with a terrigenous content of 2.6% and 1.5–2.5% of organic matter. After a detailed investigation of all the different forms of stone decay, our conclusion is that the main type of damage affecting Campanile limestone has morphologies similar to a mechanical fracture with breakages of convex surfaces and resulting very sharp edges. The process of decay is caused by the expansion of the rock during the drying process, which has a very rapid and aggressive effect on the rock. Laboratory tests showed that through extreme drying in the presence of a magnesium sulphate solution, the salt crystallization inside the stone generates a strength greater than the tensile strength of the stone, thus causing a fracture and the loosening of rock fragments. The materials introduced in recent restorations (sandstone and Portland cement) provide the necessary magnesium for the development of this weathering in Campanile limestone.

Exponential vs. slower decay of time dependent structure factors

This article deals with the possible forms of decay of time dependent structure factors in rather generic systems. It concentrates on the distinction between exponential and slower forms of decay. The common form of decay is assumed traditionally to be exponential or approximately so. Slow decay on the other hand, is characteristic of systems such as glasses that may be viewed as being very special. The purpose of the present article is to show, that slow decay is not related necessarily to the system under consideration but rather to the structure factor we prefer to measure. We may think of the decay of structure factors in certain systems as being exponential or slow but this may just reflect experimental practical preference to measure certain correlations and not others.

On Granular Stress Statistics: Compactivity, Angoricity, and Some Open Issues

We discuss the microstates of compressed granular matter in terms of two independent ensembles: one of volumes and another of boundary force moments. The former has been described in the literature and gives rise to the concept of compactivity: a scalar quantity that is the analogue of temperature in thermal systems. The latter ensemble gives rise to another analogue of the temperature: an angoricity tensor. We discuss averages under either of the ensembles and their relevance to experimental measurements. We also chart the transition from the microcanoncial to a canonical description for granular materials and show that one consequence of the traditional treatment is that the well-known exponential distribution of forces in granular systems subject to external forces is an immediate consequence of the canonical distribution, just as in the microcanonical description E = H leads to exp (-H/kT). We also put this conclusion in the context of observations of nonexponential forms of decay. We then present a Boltzmann-equation and Fokker-Planck approaches to the problem of diffusion in dense granular systems. Our approach allows us to derive, under simplifying assumptions, an explicit relation between the diffusion constant and the value of the hitherto elusive compactivity. We follow with a discussion of several unresolved issues. One of these issues is that the lack of ergodicity prevents convenient translation between time and ensemble averages, and the problem is illustrated in the context of diffusion. Another issue is that it is unclear how to make use in the statistical formalism the emerging ability to exactly predict stress fields for given structures of granular systems.

Investigating the Material World

Corrosion is a big problem. From metal and concrete to polymers and electronics, different forms of decay lead to structural and functional failures that can sometimes be of fundamental importance. The Swedish Corrosion and Metals Institute – Swerea KIMAB, is focused on developing and improving solutions for materials research. As such, they are studying corrosion in its many forms as well as the various methods used to prevent it.

New and existing forms of protective shelter at Herculaneum: towards improving the continuous care of the site

The Herculaneum Conservation Project has approached the conservation of a large-scale archaeological site (Herculaneum, Italy) suffering widespread forms of decay in two different ways: 1) with a site-wide campaign addressing conservation problems in areas most at risk and 2) with a case-study project for one urban block (Insula Orientalis I ) exploring some of the complex conservation challenges in more detail. One of these challenges is how to approach the repair of existing roofing and how to design new forms of protective shelter for those spaces that have never been covered. Short-, mid- and long-term solutions for the repair and substitution of existing roofing are being tested as part of the site-wide campaign, while in the case-study area more enduring solutions (new mid- and long-term) for new shelters are being trialled.

In situ molecular detection of some white-rot and brown-rot basidiomycetes infecting temperate and tropical woods

Wood-decay white-rot and brown-rot fungi have a major economic impact on commercial and manufactured tropical and temperate woods. The aim of this study was to design a molecular method, coupled with polymerase chain reaction (PCR) and DNA sequencing, to enable early identification of various forms of fungal decay in various types of wood. The resulting tool could be used to certify the healthiness of commercial woods and also to make more efficient use of chemicals and thus reduce their negative environmental impact. Sapwood plates of Distemonanthus benthamianus,Fagus sylvatica, Lophira alata, Pinus sylvestris, and Pycnanthus angolensis were incubated in vitro in the presence of Fibroporia vaillantii, Coniophora puteana, Gloeophyllum trabeum, Pycnoporus sanguineus, and Trametes versicolor according to the EN 113 standard method. Average mass losses ranging from 2.6% to 25.0% indicated that all wood samples had been actually infected and enabled us to test the reliability of our method. PCR products were obtained in 24 of 25 combinations, and DNA sequences were obtained in 21 of the 24 fungal PCR products. DNA sequences obtained from infected wood were compared with sequences from pure strains, thus confirming the identity of the infecting strains with 100% similarity for an average of 412 bp.

Provenance of the ornamental stones used in the baroque church of S. Pietro in Valle (Fano, Central Italy) and commentary on their state of conservation

An archaeometric study of the ornamental stones in the interior of the baroque church of San Pietro in Valle (Fano) has been carried out. On the basis of mineralogical, petrographic and geochemical studies, the areas of quarrying of 44 lithotypes are firstly established and a complete database of the location of the decorative marbles in the church was also provided. Both marbles from the Mediterranean region, used in the Roman and Byzantine period, and stones more typically found in baroque buildings were widely employed. Among the ornamental stones of local (Italian) provenance, a large number of lithotypes from the neighbourhood of Verona (Veneto Region, northern Italy) has been found. It is worthnoting that a fundamental role in choosing several marbles from Verona was played by Abbot Domenico Federici who arrived in Fano after he had been appointed secretary to the imperial embassy in Venice. Petrographic descriptions have been provided for Breccia di Brentonico, Lumachella di S.Vitale, Astracane di Verona and Nero Nube Conchigliato, which are four ornamental stones (never described in detail elsewhere) extensively quarried in the Venetian region. An isotope geochemistry study of the white marbles ( Marmor Proconnesium and Marmor Lunense) has also been carried out. Most of the ornamental stones show severe and different forms of decay, and therefore, conservation work is strongly urged. Crystallisation of salts in the pores of the rocks is the main cause of the decay shown by most of the lithotypes. The soluble salts largely originate from (i) the rising damp which affects the outer walls of the church and subordinately from (ii) inappropriate works undertaken at the beginning of the 20th century when numerous marble slabs were re-attached with gypsum grouts. The high levels of relative humidity inside the church are not consistent with the most suitable conditions for the conservation of wall paintings and decorative stones.

Complement receptor 2-mediated targeting of complement inhibitors to sites of complement activation.

In a strategy to specifically target complement inhibitors to sites of complement activation and disease, recombinant fusion proteins consisting of a complement inhibitor linked to a C3 binding region of complement receptor (CR) 2 were prepared and characterized. Natural ligands for CR2 are C3 breakdown products deposited at sites of complement activation. Fusion proteins were prepared consisting of a human CR2 fragment linked to either the N terminus or C terminus of soluble forms of the membrane complement inhibitors decay accelerating factor (DAF) or CD59. The targeted complement inhibitors bound to C3-opsonized cells, and all were significantly more effective (up to 20-fold) than corresponding untargeted inhibitors at protecting target cells from complement. CR2 fusion proteins also inhibited CR3-dependent adhesion of U937 cells to C3 opsonized erythrocytes, indicating a second potential anti-inflammatory mechanism of CR2 fusion proteins, since CR3 is involved in endothelial adhesion and diapedesis of leukocytes at inflammatory sites. Finally, the in vivo validity of the targeting strategy was confirmed by the demonstration that CR2-DAF, but not soluble DAF, targets to the kidney in mouse models of lupus nephritis that are associated with renal complement deposition.

Complement receptor 2–mediated targeting of complement inhibitors to sites of complement activation

In a strategy to specifically target complement inhibitors to sites of complement activation and disease, recombinant fusion proteins consisting of a complement inhibitor linked to a C3 binding region of complement receptor (CR) 2 were prepared and characterized. Natural ligands for CR2 are C3 breakdown products deposited at sites of complement activation. Fusion proteins were prepared consisting of a human CR2 fragment linked to either the N terminus or C terminus of soluble forms of the membrane complement inhibitors decay accelerating factor (DAF) or CD59. The targeted complement inhibitors bound to C3-opsonized cells, and all were significantly more effective (up to 20-fold) than corresponding untargeted inhibitors at protecting target cells from complement. CR2 fusion proteins also inhibited CR3-dependent adhesion of U937 cells to C3 opsonized erythrocytes, indicating a second potential anti-inflammatory mechanism of CR2 fusion proteins, since CR3 is involved in endothelial adhesion and diapedesis of leukocytes at inflammatory sites. Finally, the in vivo validity of the targeting strategy was confirmed by the demonstration that CR2-DAF, but not soluble DAF, targets to the kidney in mouse models of lupus nephritis that are associated with renal complement deposition.

A uniform approximation for the fidelity in chaotic systems

In quantum/wave systems with chaotic classical analogues, wavefunctions evolve in highly complex, yet deterministic ways. A slight perturbation of the system, though, will cause the evolution to diverge from its original behaviour increasingly with time. This divergence can be measured by the fidelity, which is defined as the squared overlap of the two time evolved states. For chaotic systems, two main decay regimes of either Gaussian or exponential behaviour have been identified depending on the strength of the perturbation. For perturbation strengths intermediate between the two regimes, the fidelity displays both forms of decay. By applying a complementary combination of random matrix and semiclassical theory, a uniform approximation can be derived that covers the full range of perturbation strengths. The time dependence is entirely fixed by the density of states and the so-called transition parameter, which can be related to the phase space volume of the system and the classical action diffusion constant, respectively. The accuracy of the approximations is illustrated with the standard map.

Principal decay patterns on Venetian monuments

Abstract In most Venetian monuments studied, the stone decay was ascribed to the transformation of calcium carbonate into calcium sulphate. This phenomenon is commonly observed elsewhere and has been pointed out by many authors. In order to explain why different forms of decay are present on a building facade, samples were taken from different areas of many monuments. Analytical results were related to different forms of decay, defined respectively as white washing, dirt accumulation and dirt wetting. A simplified model of stone decay is presented and its validity tested on several Venetian monuments. Results showed that the features visible on stone surfaces corresponded to different degrees of deterioration. Sulphate formation is greatest in the black dendrite-shaped crusts, which are generally formed at the interface between the white washing areas and the sheltered ones, which were defined as dirt wetting area. The decay forms of the most common lithotypes used in Venetian monuments were also studied. Results obtained showed that in compact limestone, gypsum formation affects the stone only on the surface. In contrast, on marble a different mechanism of decay takes place: the decohesion of calcite crystals, due to thermal changes, favours the penetration of sulphuric acid solution into intergranular spaces, thus causing the transformation of calcium carbonate into calcium sulphate, not only on the surface, but also inside the marble.

Analysis of Character Correlations Among Wood Decay Mechanisms, Mating Systems, and Substrate Ranges in Homobasidiomycetes

Homobasidiomycetes include the majority of wood-decaying fungi. Two basic forms of wood decay are known in homobasidiomycetes: white rot, in which lignin and cellulose are degraded, and brown rot, in which lignin is not appreciably degraded. An apparent correlation has been noted between production of a brown rot, decay of conifer substrates, and possession of a bipolar mating system (which has a single mating-type locus, in contrast to tetrapolar systems, which have two mating-type loci). The goals of this study were to infer the historical pattern of transformations in decay mode, mating type, and substrate range characters, and to determine if a causal relationship exists among them. Using nuclear and mitochondrial rDNA sequences, we performed a phylogenetic analysis of 130 species of homobasidiomycetes and performed ancestral state reconstructions by using parsimony on a range of trees, with various loss:gain cost ratios. We evaluated pairwise character correlations by using the concentrated changes test (CCT) of Maddison and the maximum likelihood (ML) method of Pagel. White rot, tetrapolar mating systems, and the ability to decay conifers and hardwoods appear to be plesiomorphic in homobasidiomycetes, whereas brown rot, bipolar mating systems, and exclusive decay of conifers appear to have evolved repeatedly. The only significant correlation among characters was that between brown rot (as the independent character) and exclusive decay of conifer substrates (P < 0.03). This correlation was supported by the CCT on a range of plausible trees, although not with every reconstruction of ancestral states, and by the ML test. Our findings suggest that the evolution of brown rot has promoted repeated shifts to specialization for confier substrates.

Autozygosity mapping: A tool to establish the functional role of specific human gene products

Completion of the human genome project it providing us with a complete catalogue of human genes. However, the function of many of these genes remains obscure. One approach to establishing gene function is to study the consequences of transgenic knockouts. Unfortunately, the phenotype generated in mouse knockouts does not always match that arising in man. We have been studying a highly inbred population in which consanguineous marriage leads to the occurrence of rare, autosomal recessive diseases. The technique of [autozygosity mapping] allows the gene mutated in each of these diseases to be located in the genome, and subsequently cloned. Functional pointers are provided by the disease phenotype. Examples of genes mutated in hereditary forms of deafness, tooth decay and cleft palate will be presented.

Political Development, Revisited

This article reviews four decades of scholarship on political development. It contends that the theoretical ambitions of the early political development literature to frame the comparative inquiry of politics and political change in less developed countries were undermined by intellectual challenges to the paradigms of modernization and structural functionalism and that the literature’s teleological dimension was contradicted by real-world events. Nonetheless, in subsequent decades, the field made great advances in the study of political institutions, democratic stability and breakdown, state structures, civil society, and the uneven character of political development itself. The article argues that amid manifold evidence of plural forms of political development and decay at the century’s end, the field should avoid relapses into neomodernization theory and instead focus on such issues as state reform, democratic governance, political representation and accountability, and the organization of civil societies. Such an expansive and fluid research agenda will enable the field of political development to generate important theoretical advances in comparative politics.

Pigs express multiple forms of decay accelerating factor (CD55), all of which contain only three Short Consensus Repeats (SCR)

Pigs express multiple forms of decay accelerating factor (CD55), all of which contain only three Short Consensus Repeats (SCR)

Mineralogical decay processes in stones: the case of Lleida Cathedral

This paper describes the composition, decay patterns and degradation mechanisms of the building stones and mortars of the Cathedral of Lleida (Catalonia, Spain). Various areas present considerable damage. Four forms of decay are apparent: grain disintegration, joint mortar loss, flaking and efflorescence. The type of stone, its composition and the orientation of the building determine the appearance of the decay forms. The paper analyses these altered mineral forms in the monument, and discusses their possible origin at the level of mineral reactions and stability.