Ultrastructure of developing tooth plates in the Australian lungfish, Neoceratodus forsteri (Osteichthyes : Dipnoi)

While the lungfish dentition is partially understood as far as morphology and light microscopic structure is concerned, the ultrastructure is not. Each tooth plate is associated with a dental lamina that develops from the inner layer of endodermal cells that form the oral epithelium. Dentines, bone and cartilage of the jaws differentiate from mesenchyme cells aggregating beneath the oral endothelium. Enamel, in the developing and in the mature form, has similarities to that of other early vertebrates, but unusual characters appear as development proceeds. Ameloblasts are capable of secreting enamel, and, with mononuclear osteoclasts, of remodelling the bone below the tooth plate. The forms of dentine, all based largely on an extracellular matrix of collagen and mineralised with biological apatite, differ from each other and from the underlying bone in the ultrastructure of associated cells and in the mineralised extracellular matrices produced. Cell processes emerging from the odontoblasts and from the osteoblasts vary in length, degree of branching and of anastomoses between the processes, although all of the cell types have large amounts of rough endoplasmic reticulum. Mineralisation of the extracellular matrices varies among the enamel, dentines and bone in the tooth plate. In addition, the development of the hard tissues of the tooth plates indicates that many of the similarities in fine structure of the dentition in lungfish, to tissues in other fish and amphibia, apparent early in development, disappear as the dentition matures. (C) 2003 Elsevier Ltd. All rights reserved.

Developmental anomalies in the tooth plates and jaw bones of lungfish

Lungfish of the tooth-plated lineage, both fossil and living, may be affected by alterations in the permanent tooth plates and associated jaw bones as they grow. In a few taxa, the unusual structures may be so common that they must be considered as normal for those species, or as a variation of the normal condition. In others the condition is rare, affecting only a few individuals. Variations, or anomalies, may appear in the growing tissues of the lungfish tooth plate at any time in the life cycle, although they usually appear early in development. Once the changes appear, they persist in the dentition. The altered structures include divided or intercalated ridges, short ridge anomaly, changes in the shape, number and position of cusps, pattern loss, and fused ridges or cusps. Criteria used to distinguish alteration from normal conditions are the incidence of the character in the population, the associated changes in the jaw bone, and the position of the altered structure in the tooth plate. The occurrence of similar changes across a wide range of different species suggests that they may have a genetic cause, especially when they are a rare occurrence in most taxa, but common enough to be a part of the normal variation in others. Prevalence of related anomalies throughout the history of the group suggests that dipnoans of the tooth-plated lineage are closely related, despite significant differences in morphology, microstructure, and function of the denfitions.

Growth hormone receptor and insulin-like growth factor-I immunoreactivity in osteoclast-like cells during tooth eruption in the toothless (Osteopetrotic) rat following treatment with colony-stimulating factor-1

In the toothless (tl/tl) osteopetrotic rat, teeth form but fail to erupt. Treatment of tl/tl rats with colony-stimulating factor-1 (CSF-1) activates bone resorption by osteoclasts, permits tooth eruption, and up-regulates the immunoreactivity of bone marrow mononuclear cells to growth hormone receptor (GHr) and insulin-like growth factor (IGF)-I. This study examined the distribution of tartrate-resistant acid phosphatase (TRAP) and immunoreactivity for GHr and IGF-I in osteoclast-like cells located on the alveolar bone margin, adjacent to the lower first molar crown, in 14-day-old normal and tl/tl rats, following treatment with CSF-1. Osteoclast-like cells demonstrated a positive reaction for TRAP, GHr, and IGF-I in all groups. However, in tl/tl tissue, osteoclast-like cells were generally negative for GHr. There was no significant difference in the total number of TRAP, GHr, and IGF-I-positive osteoclast-like cells on the adjacent bone margin in normal, normal treated with CSF-1, and tl/tl rats. CSF-1 treatment of the tl/tl rat significantly increased the total number of osteoclast-like cells, which were positive for TRAP (p < 0.001), GHr (p < 0.05) and IGF-I (P < 0.01).

Piezoresistive sensors for force mapping of hip-prostheses

The success of artificial prosthetic replacements depends on the fixation of the artificial prosthetic component after being implanted in the thighbone. The materials for fixation are subject to mechanical stresses, which originate permanent deformations, incipient cracks and even fatigue fractures. This work shows the possibility of monitoring the mechanical stress over time in prosthesis. In this way, highly sensitive silicon thin-film piezoresistive sensors were developed attached to prosthesis and their results compared with commercial strain gauge sensors. Mechanical stress-strain experiments were performed in compressive mode, during 10,000 cycles. Experimental data was acquired at mechanical vibration frequencies of 0.5 Hz, 1 Hz and 5 Hz, and sent to a computer by means of a wireless link. The results show that there is a decrease in sensitivity of the thin-film silicon piezoresistive sensors when they are attached to the prosthesis, but this decrease does not compromise its monitoring performance. The sensitivity, compared to that of commercial strain gauges, is much larger due to their higher gauge factors (-23.5), when compared to the GFs of commercial sensors (2).

Demand response programs definition supported by clustering and classification techniques

The growing importance and influence of new resources connected to the power systems has caused many changes in their operation. Environmental policies and several well know advantages have been made renewable based energy resources largely disseminated. These resources, including Distributed Generation (DG), are being connected to lower voltage levels where Demand Response (DR) must be considered too. These changes increase the complexity of the system operation due to both new operational constraints and amounts of data to be processed. Virtual Power Players (VPP) are entities able to manage these resources. Addressing these issues, this paper proposes a methodology to support VPP actions when these act as a Curtailment Service Provider (CSP) that provides DR capacity to a DR program declared by the Independent System Operator (ISO) or by the VPP itself. The amount of DR capacity that the CSP can assure is determined using data mining techniques applied to a database which is obtained for a large set of operation scenarios. The paper includes a case study based on 27,000 scenarios considering a diversity of distributed resources in a 33 bus distribution network.

Zonal prices analysis supported by a data mining based methodology

A methodology based on data mining techniques to support the analysis of zonal prices in real transmission networks is proposed in this paper. The mentioned methodology uses clustering algorithms to group the buses in typical classes that include a set of buses with similar LMP values. Two different clustering algorithms have been used to determine the LMP clusters: the two-step and K-means algorithms. In order to evaluate the quality of the partition as well as the best performance algorithm adequacy measurements indices are used. The paper includes a case study using a Locational Marginal Prices (LMP) data base from the California ISO (CAISO) in order to identify zonal prices.

VirtualECare: group decision supported by idea generation and argumentation

In the last years there has been a considerable increase in the number of people in need of intensive care, especially among the elderly, a phenomenon that is related to population ageing (Brown 2003). However, this is not exclusive of the elderly, as diseases as obesity, diabetes, and blood pressure have been increasing among young adults (Ford and Capewell 2007). As a new fact, it has to be dealt with by the healthcare sector, and particularly by the public one. Thus, the importance of finding new and cost effective ways for healthcare delivery are of particular importance, especially when the patients are not to be detached from their environments (WHO 2004). Following this line of thinking, a VirtualECare Multiagent System is presented in section 2, being our efforts centered on its Group Decision modules (Costa, Neves et al. 2007) (Camarinha-Matos and Afsarmanesh 2001).On the other hand, there has been a growing interest in combining the technological advances in the information society - computing, telecommunications and knowledge – in order to create new methodologies for problem solving, namely those that convey on Group Decision Support Systems (GDSS), based on agent perception. Indeed, the new economy, along with increased competition in today’s complex business environments, takes the companies to seek complementarities, in order to increase competitiveness and reduce risks. Under these scenarios, planning takes a major role in a company life cycle. However, effective planning depends on the generation and analysis of ideas (innovative or not) and, as a result, the idea generation and management processes are crucial. Our objective is to apply the GDSS referred to above to a new area. We believe that the use of GDSS in the healthcare arena will allow professionals to achieve better results in the analysis of one’s Electronically Clinical Profile (ECP). This attainment is vital, regarding the incoming to the market of new drugs and medical practices, which compete in the use of limited resources.

Pyrazole or tris(pyrazolyl)ethanol oxo-vanadium(IV) complexes as homogeneous or supported catalysts for oxidation of cyclohexane under mild conditions

The oxovanadium(IV) complexes [VO(acac)(2)(Hpz)].HC(pz)(3) 1.HC(pz)(3) (acac= acetylacetonate, Hpz = pyrazole, pz = pyrazoly1) and [VOCl2{HOCH2C(pz)(3)}] 2 were obtained from reaction of [VO(acac)(2)] with hydrotris(1-pyrazolyl)methane or of VCl(3)with 2,2,2-tris(1-pyrazolyl)ethanol. The compounds were characterized by elemental analysis, IR, Far-IR and EPR spectroscopies, FAB or ESI mass-spectrometry and, for 1, by single crystal X-ray diffraction analysis. 1 and 2 exhibit catalytic activity for the oxidation of cyclohexane to the cyclohexanol and cyclohexanone mixture in homogeneous system (TONS up to 1100) under mild conditions (NCMe, 24h, room temperature) using benzoyl peroxide (BPO), tert-butyl hydroperoxide (TBHP), m-chloroperoxybenzoic acid (mCPBA), hydrogen peroxide or the urea-hydrogen peroxide adduct (UHP) as oxidants. 1 and 2 were also immobilized on a polydimethylsiloxane membrane (1-PDMS or 2-PDMS) and the systems acted as supported catalysts for the cyclohexane oxidation using the above oxidants (TONs up to 620). The best results were obtained with mCPBA or BP0 as oxidant. The effects of various parameters, such as the amount of catalyst, nitric acid, reaction time, type of oxidant and oxidant-to-catalyst molar ratio, were investigated, for both homogeneous and supported systems. (C) 2012 Elsevier B.V. All rights reserved.

Distribution system operation supported by contextual energy resource management based on intelligent SCADA

Future distribution systems will have to deal with an intensive penetration of distributed energy resources ensuring reliable and secure operation according to the smart grid paradigm. SCADA (Supervisory Control and Data Acquisition) is an essential infrastructure for this evolution. This paper proposes a new conceptual design of an intelligent SCADA with a decentralized, flexible, and intelligent approach, adaptive to the context (context awareness). This SCADA model is used to support the energy resource management undertaken by a distribution network operator (DNO). Resource management considers all the involved costs, power flows, and electricity prices, allowing the use of network reconfiguration and load curtailment. Locational Marginal Prices (LMP) are evaluated and used in specific situations to apply Demand Response (DR) programs on a global or a local basis. The paper includes a case study using a 114 bus distribution network and load demand based on real data.

Association between tooth loss and obesity in Brazilian adults: a population-based study

OBJECTIVE: To examine the association between tooth loss and general and central obesity among adults. METHODS: Population-based cross-sectional study with 1,720 adults aged 20 to 59 years from Florianópolis, Southern Brazil. Home interviews were performed and anthropometric measures were taken. Information on sociodemographic data, self-reported diabetes, self-reported number of teeth, central obesity (waist circumference [WC] > 88 cm in women and > 102 cm in men) and general obesity (body mass index [BMI] ≥ 30 kg/m²) was collected. We used multivariable Poisson regression models to assess the association between general and central obesity and tooth loss after controlling for confounders. We also performed simple and multiple linear regressions by using BMI and WC as continuous variables. Interaction between age and tooth loss was also assessed. RESULTS: The mean BMI was 25.9 kg/m² (95%CI 25.6;26.2) in men and 25.4 kg/m2 (95%CI 25.0;25.7) in women. The mean WC was 79.3 cm (95%CI 78.4;80.1) in men and 88.4 cm (95%CI 87.6;89.2) in women. A positive association was found between the presence of less than 10 teeth in at least one arch and increased mean BMI and WC after adjusting for education level, self-reported diabetes, gender and monthly per capita income. However, this association was lost when the variable age was included in the model. The prevalence of general obesity was 50% higher in those with less than 10 teeth in at least one arch when compared with those with 10 or more teeth in both arches after adjusting for education level, self-reported diabetes and monthly per capita family income. However, the statistical significance was lost after controlling for age. CONCLUSIONS: Obesity was associated with number of teeth, though it depended on the participants' age groups.

Hybrid wired/wireless PROFIBUS networks supported by bridges/routers

Fieldbus networks are becoming increasingly popular in industrial computer-controlled systems. More recently, there has been the desire to extend the capabilities of fieldbuses to cover functionalities not previously considered in such networks, with particular emphasis on industrial wireless communications. Thinking about wireless means considering hybrid wired/wireless solutions capable of interoperating with legacy (wired) systems. One possible solution is to use intermediate systems (IS) acting as repeaters to interconnect the wired and wireless parts. In contrast, we analyze a solution where intermediate systems are implemented as bridges/routers. We detail the main advantages in terms of dependability and timeliness, and propose mechanisms to manage message transactions and intercell mobility.