Development and validation of a postmortem radiological alteration index: the RA-Index.

This study aimed to derive an index quantifying the state of alteration of cadavers by quantifying the presence of gas in the body using postmortem multidetector computed tomography (MDCT) imaging, and to validate the index by defining its sensitivity and specificity. The RA (radiological alteration)-index was derived from postmortem MDCT data from 118 nontraumatically deceased people. To validate the index, 100 additional scanned bodies (50 % traumatically deceased) were retrospectively examined by two independent observers. Presence of gas at 82 sites was assessed by a radiologist, whereas a forensic pathologist only investigated the seven sites used for the RA-index. The RA-index was highly correlated to the overall presence of gas in all 82 sites (R(2) = 0.98 in the derivation set and 0.85 in the validation set). Semiquantitative evaluation of gas presence in each site showed moderate reliability (Cohen's kappa range, 0.41-0.78); nevertheless, the overall RA-index was very reliable (ICC(2,1) = 0.95; 95 % CI 0.92-0.96). Examiner using the RA-index detected heart cavities full of gas with a sensitivity of 100 % (95 % CI 51.7-100) and a specificity of 98.8 % (92.6-99.9). We conclude that determining the presence of gas at seven sites is a valid means to measure the distribution of gas due to cadaveric alteration in the entire body. The RA-index is rapid, easy-to-use, and reliable for nonexperienced users, and it is a valid method to suspect the normal presence of gas from cadaveric alteration. MDCT can be used to screen for gas embolism and to give indications for gas composition analysis (gas chromatography).

Evaluation of Muscardinus avellanarius population density by nest box and by trap checking

Population densities of marked common dormice Muscardinus avellanarius are generally based on nest box checks. As dormice also use natural cavities and leaf nests, we tried to answer the question "what proportion of the population cannot be monitored by nest boy checks", using parallel trapping sessions. We selected a forest of 1.7ha where a 5-year nest box survey revealed an annual mean of 3.4 ± 1.4 dormice per check. The trap design (permanent grid of 77 hanging platforms) was developed in June. During July and August the traps were set every second week (4 sessions of two nights = 8 nights) resulting in a total of 75 captures with mean of 9.4 dormice per night and the presence of 16 different individuals. The grid of 60 nest boxes was checked weekly (8 times) which allowed the recapture of 19 dormice with a mean of 2.4 dormice, per control day and the presence of 6 different individuals. Population density estimated by calendar of capture and the minimal number of dormice alive methods gave for nest-box checks a value of 2.4 animals/ha and the trap checks 6.6 animals/ha with the conclusion that 63% of the population were not being monitored by nest box checks.

Organisational Values as "Attractors of Chaos": An Emerging Cultural Change to Manage Organisational Complexity

Business organisations are excellent representations of what in physics and mathematics are designated "chaotic" systems. Because a culture of innovation will be vital for organisational survival in the 21st century, the present paper proposes that viewing organisations in terms of "complexity theory" may assist leaders in fine-tuning managerial philosophies that provide orderly management emphasizing stability within a culture of organised chaos, for it is on the "boundary of chaos" that the greatest creativity occurs. It is argued that 21st century companies, as chaotic social systems, will no longer be effectively managed by rigid objectives (MBO) nor by instructions (MBI). Their capacity for self-organisation will be derived essentially from how their members accept a shared set of values or principles for action (MBV). Complexity theory deals with systems that show complex structures in time or space, often hiding simple deterministic rules. This theory holds that once these rules are found, it is possible to make effective predictions and even to control the apparent complexity. The state of chaos that self-organises, thanks to the appearance of the "strange attractor", is the ideal basis for creativity and innovation in the company. In this self-organised state of chaos, members are not confined to narrow roles, and gradually develop their capacity for differentiation and relationships, growing continuously toward their maximum potential contribution to the efficiency of the organisation. In this way, values act as organisers or "attractors" of disorder, which in the theory of chaos are equations represented by unusually regular geometric configurations that predict the long-term behaviour of complex systems. In business organisations (as in all kinds of social systems) the starting principles end up as the final principles in the long term. An attractor is a model representation of the behavioral results of a system. The attractor is not a force of attraction or a goal-oriented presence in the system; it simply depicts where the system is headed based on its rules of motion. Thus, in a culture that cultivates or shares values of autonomy, responsibility, independence, innovation, creativity, and proaction, the risk of short-term chaos is mitigated by an overall long-term sense of direction. A more suitable approach to manage the internal and external complexities that organisations are currently confronting is to alter their dominant culture under the principles of MBV.

Meliponini neotropicais: o gênero Partamona Schwarz, 1939 (Hymenoptera, Apidae, Apinae) - bionomia e biogeografia

This work, dedicated to the study of nesting habits of the species of the Neotropical genus Partamona Schwarz, is a sequence to the taxonomic revision recently published elsewhere. A total of 214 nests and nest aggregations of 18 species [Partamona epiphytophila Pedro & Camargo, 2003; P. testacea (Klug, 1807); P. mourei Camargo, 1980; P. vicina Camargo, 1980; P. auripennis Pedro & Camargo, 2003; P. combinata Pedro & Camargo, 2003; P. chapadicola Pedro & Camargo, 2003; P. nhambiquara Pedro & Camargo, 2003; P. ferreirai Pedro & Camargo, 2003; P. pearsoni (Schwarz, 1938); P. gregaria Pedro & Camargo, 2003; P. batesi Pedro & Camargo, 2003; P. ailyae Camargo, 1980; P. cupira (Smith, 1863); P. mulata Moure in Camargo, 1980; P. seridoensis Pedro & Camargo, 2003; P. criptica Pedro & Camargo, 2003; P. helleri (Friese, 1900)] were studied , including data about habitat, substrate, structural characteristics, construction materials and behavior. The descriptions of the nests are illustrated with 48 drawings. Partial data of the nests of P. bilineata (Say, 1837), P. xanthogastra Pedro & Camargo, 1997, P. orizabaensis (Strand, 1919), P. peckolti (Friese, 1901), P. aequatoriana Camargo, 1980, P. musarum (Cockerell, 1917) and P. rustica Pedro & Camargo, 2003 are also presented. Nests of P. grandipennis (Schwarz, 1951), P. yungarum Pedro & Camargo, 2003, P. subtilis Pedro & Camargo, 2003, P. vitae Pedro & Camargo, 2003, P. nigrior (Cockerell, 1925), P. sooretamae Pedro & Camargo, 2003 and P. littoralis Pedro & Camargo, 2003 are unknown. The species of Partamona build notable nest entrance structures, with special surfaces for incoming / exiting bees; some of them are extremely well-elaborated and ornamented, serving as flight orientation targets. All species endemic to western Ecuador to Mexico with known nesting habits (P. orizabaensis, P. peckolti, P. xanthogastra, P. bilineata, P. aequatoriana and P. musarum) build their nests in several substrates, non-associated with termitaria, such as cavities and crevices in walls, among roots of epiphytes and in bases of palm leaves, in abandoned bird nests, under bridges, and in other protected places, except P. peckolti that occasionally occupies termite nests. In South America, on the eastern side of the Andes, only P. epiphytophila and P. helleri nest among roots of epiphytes and other substrates, non-associated with termitaria. All other species studied (P. batesi, P. gregaria, P. pearsoni, P. ferreirai, P. chapadicola, P. nhambiquara, P. vicina, P. mourei, P. auripennis, P. combinata, P. cupira, P. mulata, P. ailyae, P. seridoensis, P. criptica and P. rustica) nest inside active termite nests, whether epigeous or arboreous. The only species that builds obligate subterranean nests, associated or not with termite or ant nests (Atta spp.) is P. testacea. Nests of Partamona have one vestibular chamber (autapomorphic for the genus) closely adjacent to the entrance, filled with a labyrinth of anastomosing pillars and connectives, made of earth and resins. One principal chamber exists for food and brood, but in some species one or more additional chambers are filled with food storage pots. In nests of P. vicina, there is one atrium or "false nest", between the vestibule and the brood chamber, which contains involucral sheaths, cells and empty pots. All structures of the nest are supported by permanent pillars made of earth and resins (another autapomorphy of the genus). The characters concerning nesting habits were coded and combined with morphological and biogeographic data, in order to hypothesize the evolutive scenario of the genus using cladistic methodology. The phylogenetic hypothesis presented is the following: (((((P. bilineata (P. grandipennis, P. xanthogastra)) (P. orizabaensis, P. peckolti)) (P. aequatoriana, P. musarum)) P. epiphytophila, P. yungarum, P. subtilis, P. vitae) (((((P. testacea (P. mourei, P. vicina)) (P. nigrior (P. auripennis, P. combinata))) (P. ferreirai (P. pearsoni (P. gregaria (P. batesi (P. chapadicola, P. nhambiquara)))))) ((((P. ailyae, P. sooretamae) P. cupira, P. mulata) P. seridoensis) P. criptica, P. rustica, P. littoralis)) P. helleri))). One area cladogram is presented. Dates of some vicariance / cladogenesis events are suggested. For bilineata / epiphytophila group, which inhabits the Southwestern Amazonia and the Chocó-Mexican biogeographical components, the origin of ancestral species is attributed to the Middle Miocene, when the transgressions of the Maracaibo and Paranense seas isolated the tropical northwestern South America from the eastern continental land mass. The next cladogenic event in the history of the bilineata / epiphytophila group is attributed to the Plio-Pleistocene, when the Ecuadorian Andes reached more than 3000 m, and the ancestral species was fragmented in two populations, one occupying the western Andes (ancestral species of the bilineata subgroup) and other the southwestern Amazon (ancestral species of the epiphytophila subgroup). Other aspects of the history of Partamona are also discussed.

Organisational values as "attractors of chaos": An emerging cultural change to manage organisational complexity

Business organisations are excellent representations of what in physics and mathematics are designated "chaotic" systems. Because a culture of innovation will be vital for organisational survival in the 21st century, the present paper proposes that viewing organisations in terms of "complexity theory" may assist leaders in fine-tuning managerial philosophies that provide orderly management emphasizing stability within a culture of organised chaos, for it is on the "boundary of chaos" that the greatest creativity occurs. It is argued that 21st century companies, as chaotic social systems, will no longer be effectively managed by rigid objectives (MBO) nor by instructions (MBI). Their capacity for self-organisation will be derived essentially from how their members accept a shared set of values or principles for action (MBV). Complexity theory deals with systems that show complex structures in time or space, often hiding simple deterministic rules. This theory holds that once these rules are found, it is possible to make effective predictions and even to control the apparent complexity. The state of chaos that self-organises, thanks to the appearance of the "strange attractor", is the ideal basis for creativity and innovation in the company. In this self-organised state of chaos, members are not confined to narrow roles, and gradually develop their capacity for differentiation and relationships, growing continuously toward their maximum potential contribution to the efficiency of the organisation. In this way, values act as organisers or "attractors" of disorder, which in the theory of chaos are equations represented by unusually regular geometric configurations that predict the long-term behaviour of complex systems. In business organisations (as in all kinds of social systems) the starting principles end up as the final principles in the long term. An attractor is a model representation of the behavioral results of a system. The attractor is not a force of attraction or a goal-oriented presence in the system; it simply depicts where the system is headed based on its rules of motion. Thus, in a culture that cultivates or shares values of autonomy, responsibility, independence, innovation, creativity, and proaction, the risk of short-term chaos is mitigated by an overall long-term sense of direction. A more suitable approach to manage the internal and external complexities that organisations are currently confronting is to alter their dominant culture under the principles of MBV.

The Smiling Project: development of a new program for gait and balance training

Introduction: The SMILING project, a multicentric project fundedby the European Union, aims to develop a new gait and balance trainingprogram to prevent falls in older persons. The program includes the"SMILING shoe", an innovative device that generates mechanical perturbationwhile walking by changing the soles' inclination. Induced perturbationschallenge subjects' balance and force them to react to avoidfalls. By training specifically the complex motor reactions used to maintainbalance when walking on irregular ground, the program will improvesubjects' ability to react in situation of unsteadiness and reduce theirrisk of falling. Methods: The program will be evaluated in a multicentric,cross-over randomized controlled trial. Overall, 112 subjects (aged≥65 years, ≥1 falls, POMA score 22-26/28) will be enrolled. Subjectswill be randomised in 2 groups: group A begin the training with active"SMILING shoes", group B with inactive dummy shoes. After 4 weeksof training, group A and B will exchange the shoes. Supervised trainingsessions (30 minutes twice a week for 8 weeks) include walkingtasks of progressive difficulties.To avoid a learning effect, "SMILINGshoes" perturbations will be generated in a non-linear and chaotic way.Gait performance, fear of falling, and acceptability of the program willbe assessed. Conclusion: The SMILING program is an innovative interventionfor falls prevention in older persons based on gait and balancetraining using chaotic perturbations. Because of the easy use of the"SMILING shoes", this program could be used in various settings, suchas geriatric clinics or at home.

Genesis of self-organized zebra textures in burial dolomites: Displacive veins, induced stress, and dolomitization

The dolomite veins making up rhythmites common in burial dolomites are not cement infillings of supposed cavities, as in the prevailing view, but are instead displacive veins, veins that pushed aside the host dolostone as they grew. Evidence that the veins are displacive includes a) small transform-fault-like displacements that could not have taken place if the veins were passive cements, and b) stylolites in host rock that formed as the veins grew in order to compensate for the volume added by the veins. Each zebra vein consists of crystals that grow inward from both sides, and displaces its walls via the local induced stress generated by the crystal growth itself. The petrographic criterion used in recent literature to interpret zebra veins in dolomites as cements - namely, that euhedral crystals can grow only in a prior void - disregards evidence to the contrary. The idea that flat voids did form in dolostones is incompatible with the observed optical continuity between the saddle dolomite euhedra of a vein and the replacive dolomite crystals of the host. The induced stress is also the key to the self-organization of zebra veins: In a set of many incipient, randomly-spaced, parallel veins just starting to grow in a host dolostone, each vein¿s induced stress prevents too-close neighbor veins from nucleating, or redissolves them by pressure-solution. The veins that survive this triage are those just outside their neighbors¿s induced stress haloes, now forming a set of equidistant veins, as observed.

Role of fluid mixing in deep dissolution of carbonates

The presence of cavities filled with new minerals in carbonate rocks is a common feature in oil reservoirs and lead-zinc deposits. Since groundwater equilibrates rapidly with carbonates, the presence of dissolution cavities in deep carbonate host rocks is a paradox. Two alternative geochemical processes have been proposed to dissolve carbonates at depth: hydrogen sulfide oxidation to sulfuric acid, and metal sulfide precipitation. With the aid of geochemical modeling we show that mixing two warm solutions saturated with carbonate results in a new solution that dissolves limestone. Variations in the proportion of the end-member fluids can also form a supersaturated mixture and fill the cavity with a new generation of carbonate. Mixing is in general more effective in dissolving carbonates than the aforementioned processes. Moreover, mixing is consistent with the wide set of textures and mineral proportions observed in cavity infillings.

Integration of ground-penetrating radar and microgravimetric methods to map shallow caves

Ground-penetrating radar (GPR) and microgravimetric surveys have been conducted in the southern Jura mountains of western Switzerland in order to map subsurface karstic features. The study site, La Grande Rolaz cave, is an extensive system in which many portions have been mapped. By using small station spacing and careful processing for the geophysical data, and by modeling these data with topographic information from within the cave, accurate interpretations have been achieved. The constraints on the interpreted geologic models are better when combining the geophysical methods than when using only one of the methods, despite the general limitations of two-dimensional (2D) profiling. For example, microgravimetry can complement GPR methods for accurately delineating a shallow cave section approximately 10 X 10 mt in size. Conversely, GPR methods can be complementary in determining cavity depths and in verifying the presence of off-line features and numerous areas of small cavities and fractures, which may be difficult to resolve in microgravimetric data.

Glucose is arrhythmogenic in the anoxic-reoxygenated embryonic chick heart.

Unlike in adult heart, embryonic myocardium works at low PO2 and depends preferentially on glucose. Therefore, activity of the embryonic heart during anoxia and reoxygenation should be particularly affected by changes in glucose availability. Hearts excised from 4-d-old chick embryos were submitted in vitro to strictly controlled anoxia-reoxygenation transitions at glucose concentrations varying from 0 to 20 mmol/L. Spontaneous and regular heart contractions were detected optically as movements of the ventricle wall and instantaneous heart rate, amplitude of contraction, and velocities of contraction and relaxation were determined. Anoxia induced transient tachycardia and rapidly depressed contractile activity, whereas reoxygenation provoked a temporary and complete cardioplegia (oxygen paradox). In the presence of glucose, atrial rhythm became irregular during anoxia and chaotic-periodic during reoxygenation. The incidence of these arrhythmias depended on duration of anoxia, and no ventricular ectopic beats were observed. Removal of glucose or blockade of glycolysis suppressed arrhythmias. These results show similarities but also differences with respect to the adult heart. Indeed, glucose 1) delayed and anoxic contractile failure, shortened the reoxygenation-induced cardiac arrest, and improved the recovery of contractile activity; 2) attenuated stunning at 20 mmol/L but worsened it at 8 mmol/L; and 3) paradoxically, was arrhythmogenic during anoxia and reoxygenation, especially when present at the physiologic concentration of 8 mmol/L. The last named phenomenon seems to be characteristic of the young embryonic heart, and our findings underscore that fluctuations of glycolytic activity may play a role in the reactivity of the embryonic myocardium to anoxiareoxygenation transitions.

Effects of different management systems on porosity of oxisols in Paraná, Brazil

Soils play a fundamental role in the production of human foods. The Oxisols in the state of Paraná are among the richest and most productive soils in Brazil, but degradation and low porosity are frequently documented, due to intensive farming involving various management strategies and the application of high-tech solutions. This study aims to investigate changes in the porosity of two Red Oxisols (Latossolos Vermelhos), denoted LVef (eutroferric) and LVdf (dystroferric) under conventional and no-tillage soil management, with a succession of annual crops of soybean, maize and wheat over a continuous period of more than 20 years. After describing the soil profiles under native forest, no-tillage management and conventional tillage using the crop profile method, deformed and non-deformed soil samples were collected from the volumes most compacted by human intervention and the physical, chemical and mineralogical properties analyzed. The various porosity classes (total pore volume, inter-aggregate porosity between channels and biological cavities) and intra-aggregate porosity (determined in 10 cm³ saturated clods subjected to a pressure of -10 kPa to obtain a pore volume with a radius (r eq), > 15 μm and < 15 μm). The results showed that the effects of no-tillage farming on porosity are more pronounced in both soil types. Porosity of the LVdf was higher than pf the LVef soil, whatever the management type. In the LVdf soil, only pores with a radius of > 15 μm were affected by farming whereas in the LVef soil, pores with a radius of < 15 μm were affected as well.

Dissipation in quasistatically driven disordered systems

This work presents an analysis of hysteresis and dissipation in quasistatically driven disordered systems. The study is based on the random field Ising model with fluctuationless dynamics. It enables us to sort out the fraction of the energy input by the driving field stored in the system and the fraction dissipated in every step of the transformation. The dissipation is directly related to the occurrence of avalanches, and does not scale with the size of Barkhausen magnetization jumps. In addition, the change in magnetic field between avalanches provides a measure of the energy barriers between consecutive metastable states

Density modes in spherical 4He shells

We compute the density-fluctuation spectrum of spherical 4HeN shells adsorbed on the outer surface of Cn fullerenes. The excitation spectrum is obtained within the random-phase approximation, with particle-hole elementary excitations and effective interaction extracted from a density-functional description of the shell structure. The presence of one or two solid helium layers adjacent to the adsorbing fullerene is phenomenologically accounted for. We illustrate our results for a selection of numbers of adsorbed atoms on C20, C60, and C120. The hydrodynamical model that has proven successful to describe helium excitations in the bulk and in restricted geometries permits to perform a rather exhaustive analysis of various fluid spherical systems, namely, spheres, cavities, free bubbles, and bound shells of variable size.

Dynamics of domain walls in pattern formation under traveling-wave forcing

We study dynamics of domain walls in pattern forming systems that are externally forced by a moving space-periodic modulation close to 2:1 spatial resonance. The motion of the forcing induces nongradient dynamics, while the wave number mismatch breaks explicitly the chiral symmetry of the domain walls. The combination of both effects yields an imperfect nonequilibrium Ising-Bloch bifurcation, where all kinks (including the Ising-like one) drift. Kink velocities and interactions are studied within the generic amplitude equation. For nonzero mismatch, a transition to traveling bound kink-antikink pairs and chaotic wave trains occurs.

Bifurcations and chaos in single-roll natural convection with low Prandtl number

Convective flows of a small Prandtl number fluid contained in a two-dimensional cavity subject to a lateral thermal gradient are numerically studied by using different techniques. The aspect ratio (length to height) is kept at around 2. This value is found optimal to make the flow most unstable while keeping the basic single-roll structure. Two cases of thermal boundary conditions on the horizontal plates are considered: perfectly conducting and adiabatic. For increasing Rayleigh numbers we find a transition from steady flow to periodic oscillations through a supercritical Hopf bifurcation that maintains the centrosymmetry of the basic circulation. For a Rayleigh number of about ten times that of the Hopf bifurcation the system initiates a complex scenario of bifurcations. In the conductive case these include a quasiperiodic route to chaos. In the adiabatic one the dynamics is dominated by the interaction of two Neimark-Sacker bifurcations of the basic periodic solutions, leading to the stable coexistence of three incommensurate frequencies, and finally to chaos. In all cases, the complex time-dependent behavior does not break the basic, single-roll structure.