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Sample records for stepping stone model

  1. Genetic demixing and evolution in linear stepping stone models

    Science.gov (United States)

    Korolev, K. S.; Avlund, Mikkel; Hallatschek, Oskar; Nelson, David R.

    2010-04-01

    Results for mutation, selection, genetic drift, and migration in a one-dimensional continuous population are reviewed and extended. The population is described by a continuous limit of the stepping stone model, which leads to the stochastic Fisher-Kolmogorov-Petrovsky-Piscounov equation with additional terms describing mutations. Although the stepping stone model was first proposed for population genetics, it is closely related to “voter models” of interest in nonequilibrium statistical mechanics. The stepping stone model can also be regarded as an approximation to the dynamics of a thin layer of actively growing pioneers at the frontier of a colony of micro-organisms undergoing a range expansion on a Petri dish. The population tends to segregate into monoallelic domains. This segregation slows down genetic drift and selection because these two evolutionary forces can only act at the boundaries between the domains; the effects of mutation, however, are not significantly affected by the segregation. Although fixation in the neutral well-mixed (or “zero-dimensional”) model occurs exponentially in time, it occurs only algebraically fast in the one-dimensional model. An unusual sublinear increase is also found in the variance of the spatially averaged allele frequency with time. If selection is weak, selective sweeps occur exponentially fast in both well-mixed and one-dimensional populations, but the time constants are different. The relatively unexplored problem of evolutionary dynamics at the edge of an expanding circular colony is studied as well. Also reviewed are how the observed patterns of genetic diversity can be used for statistical inference and the differences are highlighted between the well-mixed and one-dimensional models. Although the focus is on two alleles or variants, q -allele Potts-like models of gene segregation are considered as well. Most of the analytical results are checked with simulations and could be tested against recent spatial

  2. Secondary Special Education. Part I: The "Stepping Stone Model" Designed for Secondary Learning Disabled Students. Part II: Adapting Materials and Curriculum.

    Science.gov (United States)

    Fox, Barbara

    The paper describes the Stepping Stone Model, a model for the remediation and mainstreaming of secondary learning disabled students and the adaptation of curriculum and materials for the model. The Stepping Stone Model is designed to establish the independence of students in the mainstream through content reading. Five areas of concern common to…

  3. Comparing the efficacy of metronome beeps and stepping stones to adjust gait: steps to follow!

    Science.gov (United States)

    Bank, Paulina J M; Roerdink, Melvyn; Peper, C E

    2011-03-01

    Acoustic metronomes and visual targets have been used in rehabilitation practice to improve pathological gait. In addition, they may be instrumental in evaluating and training instantaneous gait adjustments. The aim of this study was to compare the efficacy of two cue types in inducing gait adjustments, viz. acoustic temporal cues in the form of metronome beeps and visual spatial cues in the form of projected stepping stones. Twenty healthy elderly (aged 63.2 ± 3.6 years) were recruited to walk on an instrumented treadmill at preferred speed and cadence, paced by either metronome beeps or projected stepping stones. Gait adaptations were induced using two manipulations: by perturbing the sequence of cues and by imposing switches from one cueing type to the other. Responses to these manipulations were quantified in terms of step-length and step-time adjustments, the percentage correction achieved over subsequent steps, and the number of steps required to restore the relation between gait and the beeps or stepping stones. The results showed that perturbations in a sequence of stepping stones were overcome faster than those in a sequence of metronome beeps. In switching trials, switching from metronome beeps to stepping stones was achieved faster than vice versa, indicating that gait was influenced more strongly by the stepping stones than the metronome beeps. Together these results revealed that, in healthy elderly, the stepping stones induced gait adjustments more effectively than did the metronome beeps. Potential implications for the use of metronome beeps and stepping stones in gait rehabilitation practice are discussed.

  4. Stepping Stones to Evaluating Your Own School Literacy Program

    Science.gov (United States)

    Levesque, Jeri; Carnahan, Danielle

    2005-01-01

    Stepping Stones to Literacy is a tool for elementary school improvement teams to evaluate and strengthen their reading programs. Each Stepping Stone is a guided activity to stimulate reflection and guide systematic inquiry. It is a collaborative, active research approach to evaluation (Levesque & Hinton 2001). The goal is to eliminate the gap…

  5. Robust Detection of Stepping-Stone Attacks

    National Research Council Canada - National Science Library

    He, Ting; Tong, Lang

    2006-01-01

    The detection of encrypted stepping-stone attack is considered. Besides encryption and padding, the attacker is capable of inserting chaff packets and perturbing packet timing and transmission order...

  6. Stepping Stones to Research: Providing Pipelines from Middle School through PhD

    Science.gov (United States)

    Noel-Storr, Jacob; Baum, S. A.; RIT Insight Lab SSR Team; Carlson CenterImaging Science Faculty, Chester F.

    2014-01-01

    We present a decade's worth of strategies designed to promote and provide "Stepping Stones to Research" to provide a realistic pipeline of educational opportunities, with multiple gateways and exit points, for students moving towards STEM careers along the "STEM pipeline". We also illustrate how the Stepping Stones are designed to incidentally co-inside with related external opportunities through which we can also guide and support our mentees on their paths. We present programs such as middle school family science programs, high school research opportunities, high school internships, undergraduate research pathways, research experiences for undergraduates, and other opportunities. We will highlight the presentations being made at this very meeting -- from the first presentation of a high school student, to a dissertation presentation of a PhD graduate -- that have benefited from this stepping stone principle. We also reflect on the essential nature of building a "researcher-trust", even as a young student, of advocates and mentors who can support the continuation of a scientific career.

  7. Informality as a stepping stone: A search-theoretical assessment of informal sector and government policy

    Directory of Open Access Journals (Sweden)

    Semih Tümen

    2016-09-01

    Full Text Available This paper develops a model of sequential job search to understand the factors determining the effect of tax and enforcement policies on the size (i.e., employment share of informal sector. The focus is on the role of informal sector as a stepping stone to formal jobs. I argue that the stepping-stone role of informal jobs is an important concept determining how strongly government policies affect the size of informal sector. I measure the extent of the stepping-stone role with the intensity of skill accumulation in the informal sector. If informal jobs help workers acquire skills, gain expertise, and build professional networks for boosting the chances to switch to a formal job, then the size of informal sector is less sensitive to government policy. In this case, the option value of a job in informal sector will be high and a worker with an informal job will not rush to switch to a formal job when a policy encouraging formal employment is in effect. If, on the other hand, informal sector does not provide satisfactory training opportunities, then the size of informal sector becomes more sensitive to government policy. Calibrating the model to the Brazilian data, I perform numerical exercises confirming that the effect of government policy on the size of informal sector is a decreasing function of the intensity of skill acquisition in the informal sector.

  8. Habitat continuity and stepping-stone oceanographic distances explain population genetic connectivity of the brown alga Cystoseira amentacea.

    Science.gov (United States)

    Buonomo, Roberto; Assis, Jorge; Fernandes, Francisco; Engelen, Aschwin H; Airoldi, Laura; Serrão, Ester A

    2017-02-01

    Effective predictive and management approaches for species occurring in a metapopulation structure require good understanding of interpopulation connectivity. In this study, we ask whether population genetic structure of marine species with fragmented distributions can be predicted by stepping-stone oceanographic transport and habitat continuity, using as model an ecosystem-structuring brown alga, Cystoseira amentacea var. stricta. To answer this question, we analysed the genetic structure and estimated the connectivity of populations along discontinuous rocky habitat patches in southern Italy, using microsatellite markers at multiple scales. In addition, we modelled the effect of rocky habitat continuity and ocean circulation on gene flow by simulating Lagrangian particle dispersal based on ocean surface currents allowing multigenerational stepping-stone dynamics. Populations were highly differentiated, at scales from few metres up to thousands of kilometres. The best possible model fit to explain the genetic results combined current direction, rocky habitat extension and distance along the coast among rocky sites. We conclude that a combination of variable suitable habitat and oceanographic transport is a useful predictor of genetic structure. This relationship provides insight into the mechanisms of dispersal and the role of life-history traits. Our results highlight the importance of spatially explicit modelling of stepping-stone dynamics and oceanographic directional transport coupled with habitat suitability, to better describe and predict marine population structure and differentiation. This study also suggests the appropriate spatial scales for the conservation, restoration and management of species that are increasingly affected by habitat modifications. © 2016 John Wiley & Sons Ltd.

  9. Stepping Stones: Evolving the Earth and Its Life

    Science.gov (United States)

    McKay, Christopher P.

    In recent years, science has begun to consider more system-level studies that cross disciplines. These studies challenge our traditional disciplinary training. It is no longer enough to be just a geologist when the problems of interest deal with an entire planet. Indeed, a knowledge of biology, geology astronomy, and myriad subfields is needed. In Stepping Stones, Stephen Drury steps up to the daunting task of writing a general treatment of the science of the entire Earth. He not only ranges through all of the relevant physical sciences but also reaches to economics and political theory. The material is presented at a general level with reading lists but no specific references. Equations have been minimized.

  10. Modeling Stone Columns.

    Science.gov (United States)

    Castro, Jorge

    2017-07-11

    This paper reviews the main modeling techniques for stone columns, both ordinary stone columns and geosynthetic-encased stone columns. The paper tries to encompass the more recent advances and recommendations in the topic. Regarding the geometrical model, the main options are the "unit cell", longitudinal gravel trenches in plane strain conditions, cylindrical rings of gravel in axial symmetry conditions, equivalent homogeneous soil with improved properties and three-dimensional models, either a full three-dimensional model or just a three-dimensional row or slice of columns. Some guidelines for obtaining these simplified geometrical models are provided and the particular case of groups of columns under footings is also analyzed. For the latter case, there is a column critical length that is around twice the footing width for non-encased columns in a homogeneous soft soil. In the literature, the column critical length is sometimes given as a function of the column length, which leads to some disparities in its value. Here it is shown that the column critical length mainly depends on the footing dimensions. Some other features related with column modeling are also briefly presented, such as the influence of column installation. Finally, some guidance and recommendations are provided on parameter selection for the study of stone columns.

  11. Stepping Stones: Principal Career Paths and School Outcomes. Working Paper 58

    Science.gov (United States)

    Beteille, Tara; Kalogrides, Demetra; Loeb, Susanna

    2011-01-01

    Principals tend to prefer working in schools with higher-achieving students from more advantaged socioeconomic backgrounds. Principals often use schools with many poor or low-achieving students as stepping stones to what they view as more desirable assignments. District leadership can also exacerbate principal turnover by implementing policies…

  12. Ship Sensor Observations for North Atlantic Stepping Stones 2005 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hourly measurements made by selected ship sensors on the NOAA ship Ronald H. Brown during the "North Atlantic Stepping Stones 2005" expedition sponsored by the...

  13. Impact of Stepping Stones Triple P on Parents with a Child Diagnosed with Autism Spectrum Disorder: Implications for School Psychologists

    Science.gov (United States)

    VanVoorhis, Richard W.; Miller, Kenneth L.; Miller, Susan M.; Stull, Judith C.

    2015-01-01

    The Stepping Stones Positive Parenting Program (Stepping Stones Triple P; SSTP) was designed for caregivers of children with disabilities to improve select parental variables such as parenting styles, parental satisfaction, and parental competency, and to reduce parental stress and child problem behaviors. This study focused on SSTP training for…

  14. Bullying: a stepping stone to dating aggression?

    Science.gov (United States)

    Josephson, Wendy L; Pepler, Debra

    2012-01-01

    Bullying is the use of power and aggression to control and distress another. In this paper, we review research to explore whether the lessons learned in bullying provide a stepping stone to aggressive behavior in dating relationships. We start by considering definitions and a relationship framework with which to understand both bullying and dating aggression. We consider bullying from a developmental-contextual perspective and consider risk factors associated with the typical developmental patterns for bullying and dating aggression, including developmental and sociodemographic, individual attributes, and family, peer group, community, and societal relationship contexts that might lead some children and youths to follow developmental pathways that lead to bullying and dating aggression. We conclude by discussing implications for intervention with a review of evidence-based interventions.

  15. A randomized controlled trial of group Stepping Stones Triple P: a mixed-disability trial.

    Science.gov (United States)

    Roux, Gemma; Sofronoff, Kate; Sanders, Matthew

    2013-09-01

    Stepping Stones Triple P (SSTP) is a parenting program designed for families of a child with a disability. The current study involved a randomized controlled trial of Group Stepping Stones Triple P (GSSTP) for a mixed-disability group. Participants were 52 families of children diagnosed with an Autism Spectrum Disorder, Down syndrome, Cerebral Palsy, or an intellectual disability. The results demonstrated significant improvements in parent-reported child behavior, parenting styles, parental satisfaction, and conflict about parenting. Results among participants were similar despite children's differing impairments. The intervention effect was maintained at 6-month follow-up. The results indicate that GSSTP is a promising intervention for a mixed-disability group. Limitations of the study, along with areas for future research, are also discussed. © FPI, Inc.

  16. Toward a global space exploration program: A stepping stone approach

    Science.gov (United States)

    Ehrenfreund, Pascale; McKay, Chris; Rummel, John D.; Foing, Bernard H.; Neal, Clive R.; Masson-Zwaan, Tanja; Ansdell, Megan; Peter, Nicolas; Zarnecki, John; Mackwell, Steve; Perino, Maria Antionetta; Billings, Linda; Mankins, John; Race, Margaret

    2012-01-01

    In response to the growing importance of space exploration in future planning, the Committee on Space Research (COSPAR) Panel on Exploration (PEX) was chartered to provide independent scientific advice to support the development of exploration programs and to safeguard the potential scientific assets of solar system objects. In this report, PEX elaborates a stepwise approach to achieve a new level of space cooperation that can help develop world-wide capabilities in space science and exploration and support a transition that will lead to a global space exploration program. The proposed stepping stones are intended to transcend cross-cultural barriers, leading to the development of technical interfaces and shared legal frameworks and fostering coordination and cooperation on a broad front. Input for this report was drawn from expertise provided by COSPAR Associates within the international community and via the contacts they maintain in various scientific entities. The report provides a summary and synthesis of science roadmaps and recommendations for planetary exploration produced by many national and international working groups, aiming to encourage and exploit synergies among similar programs. While science and technology represent the core and, often, the drivers for space exploration, several other disciplines and their stakeholders (Earth science, space law, and others) should be more robustly interlinked and involved than they have been to date. The report argues that a shared vision is crucial to this linkage, and to providing a direction that enables new countries and stakeholders to join and engage in the overall space exploration effort. Building a basic space technology capacity within a wider range of countries, ensuring new actors in space act responsibly, and increasing public awareness and engagement are concrete steps that can provide a broader interest in space exploration, worldwide, and build a solid basis for program sustainability. By engaging

  17. Constructing Teaching Model for Training English Guides of Stone In-scription Relics

    Institute of Scientific and Technical Information of China (English)

    李慧

    2016-01-01

    A teaching model based on constructivism is proposed in this paper. The model contains five teaching steps, e.g. inter-pretation teaching, questioning-dialogue, knowledge and skills teaching, discussion-collaboration and field training. Practice proves that it can effectively improve the training efficiency of the training of English guides of stone inscription relics and en-hance their interpretation quality and English skills.

  18. Stepping Stones to Resiliency following a community-based two-generation Canadian preschool programme.

    Science.gov (United States)

    Ginn, Carla S; Benzies, Karen M; Keown, Leslie Anne; Raffin Bouchal, Shelley; Thurston, Wilfreda E Billlie

    2018-05-01

    Early intervention programmes are designed to address complex inequities for Canadian families living with low income, affecting social relationships, well-being and mental health. However, there is limited understanding of resiliency and change in families living with low income over time. We conducted a mixed methods study with recent immigrant, other Canadian-born, and Aboriginal families living with low income, who attended a two-generation preschool programme (CUPS One World) between 2002 and 2008. The aim of this study was to develop an understanding of the processes of change. We included 134 children and their caregivers living with low income, and experiencing mental health problems, addiction or social isolation. Children's receptive language, a proxy for school readiness, was measured at programme intake, exit, and age 10 years using the Peabody Picture Vocabulary Test 3rd Edition (PPVT-III). In Phase I (quantitative), we identified children with receptive language scores in the top and bottom 25th percentile, informing participant selection for Phase II. In Phase II (qualitative), we engaged in constructivist grounded theory to explore experiences of 14 biological mothers, after their children (n = 25) reached age 10 years. Interviews were conducted between June and September 2015. The core category, Stepping Stones to Resiliency, encompassed Perceptions of Family, Moving Forward, Achieving Goals, and Completely Different. Perceptions of Family influenced families' capabilities to move across the Stepping Stones to Resiliency. Stepping Stones to Resiliency provides a lens from which to view others in their daily challenges to break free of painful intergenerational cycles. It is a reminder of our struggle, our shared humanness, and that movement towards resiliency is more difficult for some than others. Our findings challenge traditional episodic, biomedical treatment paradigms for low-income families also experiencing intergenerational cycles of

  19. Atypical jobs : stepping stones or dead ends? Evidence from the NLSY79.

    OpenAIRE

    Addison, J.T.; Cotti, C.; Surfield, C.J.

    2015-01-01

    Atypical work arrangements have long been criticized as offering more precarious and lower paid work than regular open-ended employment. An important British paper by Booth et al. (Economic Journal, Vol. 112 (2002), No. 480, pp. F189–F213) was among the first to recognize such jobs also functioned as a stepping stone to permanent work. This conclusion proved prescient, receiving increased support in Europe. Here, we provide a broadly parallel analysis for the USA, where research has been less...

  20. Interpreting Stone's model of Berry phases

    International Nuclear Information System (INIS)

    Carra, Paolo

    2004-01-01

    We show that a simple quantum-mechanical model, put forward by Stone some time ago, affords a description of site magnetoelectricity, a phenomenon which takes place in crystals (and molecular systems) when space inversion is locally broken and coexistence of electric and magnetic moments is permitted by the site point group. We demonstrate this by identifying a local order parameter, which is odd under both space inversion and time reversal. This order parameter (a magnetic quadrupole) characterizes Stone's ground state. Our results indicate that the model, extended to a lattice of sites, could be relevant to the study of electronic properties of transition-metal oxides. A generalization of Stone's Hamiltonian to cover cases of different symmetry is also discussed. (letter to the editor)

  1. Stepping Stones Triple P: an RCT of a parenting program with parents of a child diagnosed with an autism spectrum disorder.

    Science.gov (United States)

    Whittingham, Koa; Sofronoff, Kate; Sheffield, Jeanie; Sanders, Matthew R

    2009-05-01

    Whilst the Triple P Positive Parenting Program has a large evidence base (Sanders, Clinical Child and Family Psychology Review 2:71-90, 1999; Sanders, Journal of Consulting and Clinical Psychology 68:624-640, 2000) and preliminary evidence indicates that Stepping Stones Triple P is also efficacious (Roberts, Journal of Clinical Child and Adolescent Psychology, 35(2):180-193, 2006), to date Stepping Stones has not been evaluated with the ASD population. Fifty-nine families with a child with ASD aged between 2 and 9 participated in this randomized controlled trial. The results demonstrate significant improvements in parental reports of child behaviour and parenting styles with the treatment effects for child behaviour, parental over reactivity and parental verbosity being maintained at follow-up 6 months later. Further, the results suggest significant improvements in parental satisfaction and conflict about parenting as well as a sleeper effect for parental efficacy. The results indicate that Stepping Stones Triple P is a promising intervention for parents of children with ASD. Limitations and future research are also addressed.

  2. Probabilistic Modeling of the Renal Stone Formation Module

    Science.gov (United States)

    Best, Lauren M.; Myers, Jerry G.; Goodenow, Debra A.; McRae, Michael P.; Jackson, Travis C.

    2013-01-01

    The Integrated Medical Model (IMM) is a probabilistic tool, used in mission planning decision making and medical systems risk assessments. The IMM project maintains a database of over 80 medical conditions that could occur during a spaceflight, documenting an incidence rate and end case scenarios for each. In some cases, where observational data are insufficient to adequately define the inflight medical risk, the IMM utilizes external probabilistic modules to model and estimate the event likelihoods. One such medical event of interest is an unpassed renal stone. Due to a high salt diet and high concentrations of calcium in the blood (due to bone depletion caused by unloading in the microgravity environment) astronauts are at a considerable elevated risk for developing renal calculi (nephrolithiasis) while in space. Lack of observed incidences of nephrolithiasis has led HRP to initiate the development of the Renal Stone Formation Module (RSFM) to create a probabilistic simulator capable of estimating the likelihood of symptomatic renal stone presentation in astronauts on exploration missions. The model consists of two major parts. The first is the probabilistic component, which utilizes probability distributions to assess the range of urine electrolyte parameters and a multivariate regression to transform estimated crystal density and size distributions to the likelihood of the presentation of nephrolithiasis symptoms. The second is a deterministic physical and chemical model of renal stone growth in the kidney developed by Kassemi et al. The probabilistic component of the renal stone model couples the input probability distributions describing the urine chemistry, astronaut physiology, and system parameters with the physical and chemical outputs and inputs to the deterministic stone growth model. These two parts of the model are necessary to capture the uncertainty in the likelihood estimate. The model will be driven by Monte Carlo simulations, continuously

  3. Predator-prey-subsidy population dynamics on stepping-stone domains with dispersal delays.

    Science.gov (United States)

    Eide, Ragna M; Krause, Andrew L; Fadai, Nabil T; Van Gorder, Robert A

    2018-08-14

    We examine the role of the travel time of a predator along a spatial network on predator-prey population interactions, where the predator is able to partially or fully sustain itself on a resource subsidy. The impact of access to food resources on the stability and behaviour of the predator-prey-subsidy system is investigated, with a primary focus on how incorporating travel time changes the dynamics. The population interactions are modelled by a system of delay differential equations, where travel time is incorporated as discrete delay in the network diffusion term in order to model time taken to migrate between spatial regions. The model is motivated by the Arctic ecosystem, where the Arctic fox consumes both hunted lemming and scavenged seal carcass. The fox travels out on sea ice, in addition to quadrennially migrating over substantial distances. We model the spatial predator-prey-subsidy dynamics through a "stepping-stone" approach. We find that a temporal delay alone does not push species into extinction, but rather may stabilize or destabilize coexistence equilibria. We are able to show that delay can stabilize quasi-periodic or chaotic dynamics, and conclude that the incorporation of dispersal delay has a regularizing effect on dynamics, suggesting that dispersal delay can be proposed as a solution to the paradox of enrichment. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Penyelesaian Persoalan Transportasi Fuzzy Cost Menggunakan Pendekatan Basis Tree dan Metode Nwc-stepping Stone

    OpenAIRE

    Ari, Maxsi; Herman, Asep

    2013-01-01

    The issue of transportation is a linier program. Practically, variables of transportation problems may vary that emerges more than single. Fuzzy cost idea in transportation problems is required. The application of basis tree approach and NWC-Stepping Stone method is used to determine a minimum cost of purchase and delivery of commodity occurred for some suppliers. The company can do a cost-saving and be more effective in determining goods purchase from the supplier. The method used is quanti...

  5. Stepping Stones Triple P : The importance of putting the findings into context - a response to Tellegen and Sofronoff

    NARCIS (Netherlands)

    Reijneveld, Sijmen A.; Kleefman, Marijke; Jansen, Danielle E. M. C.

    2015-01-01

    Recently, we reported the findings of a randomized controlled trial on the effectiveness of Stepping Stones Triple P (SSTP) compared to Care as Usual (CAU), in BMC Medicine. The study involved parents of 209 children with Borderline to Mild Intellectual Disability (BMID), included following a

  6. The MOX Demonstration Facility - the stepping stone to commercial MOX production

    International Nuclear Information System (INIS)

    Macdonald, A.G.

    1994-01-01

    The paper provides an insight into MOX fuel and the economic benefits of its use in pressurized water reactors (PWRs). BNFL and AEA are collaborating in the design, construction and operation of a thermal MOX Demonstration Facility (MDF) on the AEA Windscale site in Cumbria. The process flowsheet and equipment employed in MDF are discussed and the special precautions required to handle plutonium bearing materials are highlighted. The process flowsheet includes the short binderless route which has been specially developed for use in MDF and results in fuel pellets with an homogeneous structure. MDF is the forerunner to the design and construction of a larger scale Sellafield MOX Plant and hence is the stepping-stone to commercial MOX production. (author)

  7. Stepping stones: Principal career paths and school outcomes.

    Science.gov (United States)

    Béteille, Tara; Kalogrides, Demetra; Loeb, Susanna

    2012-07-01

    More than one out of every five principals leaves their school each year. In some cases, these career changes are driven by the choices of district leadership. In other cases, principals initiate the move, often demonstrating preferences to work in schools with higher achieving students from more advantaged socioeconomic backgrounds. Principals often use schools with many poor or low-achieving students as stepping stones to what they view as more desirable assignments. We use longitudinal data from one large urban school district to study the relationship between principal turnover and school outcomes. We find that principal turnover is, on average, detrimental to school performance. Frequent turnover of school leadership results in lower teacher retention and lower student achievement gains. Leadership changes are particularly harmful for high poverty schools, low-achieving schools, and schools with many inexperienced teachers. These schools not only suffer from high rates of principal turnover but are also unable to attract experienced successors. The negative effect of leadership changes can be mitigated when vacancies are filled by individuals with prior experience leading other schools. However, the majority of new principals in high poverty and low-performing schools lack prior leadership experience and leave when more attractive positions become available in other schools. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. A Stone Resource Assignment Model under the Fuzzy Environment

    Directory of Open Access Journals (Sweden)

    Liming Yao

    2012-01-01

    to tackle a stone resource assignment problem with the aim of decreasing dust and waste water emissions. On the upper level, the local government wants to assign a reasonable exploitation amount to each stone plant so as to minimize total emissions and maximize employment and economic profit. On the lower level, stone plants must reasonably assign stone resources to produce different stone products under the exploitation constraint. To deal with inherent uncertainties, the object functions and constraints are defuzzified using a possibility measure. A fuzzy simulation-based improved simulated annealing algorithm (FS-ISA is designed to search for the Pareto optimal solutions. Finally, a case study is presented to demonstrate the practicality and efficiency of the model. Results and a comparison analysis are presented to highlight the performance of the optimization method, which proves to be very efficient compared with other algorithms.

  9. In vitro study of transmission of bacteria from contaminated metal models to stone models via impressions

    DEFF Research Database (Denmark)

    Sofou, A.; Larsen, T.; Öwall, B.

    2002-01-01

    Dental impression, stone model, bacterial contamination, cross-infection, dental clinic, dental laboratory......Dental impression, stone model, bacterial contamination, cross-infection, dental clinic, dental laboratory...

  10. Evaluation of stepping stones as a tool for changing knowledge, attitudes and behaviours associated with gender, relationships and HIV risk in Karnataka, India.

    Science.gov (United States)

    Bradley, Janet E; Bhattacharjee, Parinita; Ramesh, Banadakoppa M; Girish, Meghna; Das, Arup K

    2011-06-24

    Stepping Stones training aims to help individuals explore sexual relationships and recognize gender inequalities, the structural drivers of the HIV epidemic, in order to understand risk behaviours and to seek solutions to factors that increase HIV vulnerability. Despite earlier studies suggesting the success of Stepping Stones, little data exist to show diffusion to trainees' social networks or the wider community. A mixed-methods evaluation of this approach was undertaken using in-depth interviews of trainees and friends, and polling booth surveys in 20 villages where Stepping Stones training took place and in another 20 villages with no Stepping Stones intervention. The interview respondents and their friends reported significant changes in their relationships after training, and benefit from discussion of gender, sexuality, condom use and HIV vulnerability issues. However, though diffusion of this knowledge at the level of personal contacts was strong, the evaluation revealed that diffusion to the community level was limited. The qualitative part of this study reflects other studies in different settings, in that SS participants gained immensely from the training. Wider behaviour change is a challenging goal that many programmes fail to attain, with most interventions too limited in scope and intensity to produce larger community effects. This may have contributed to the fact that we observed few differences between interventions and non-intervention villages in this study. However, it is also possible that we had excessive expectations of individual change at the community level, and that it might have been more appropriate to have had broader community level rather than individual behavioural change indicators. We suggest that SS could be enhanced by efforts to better engage existing community opinion leaders, to empower and train participants as community change agents, and to support the development of village-level action plans that combat sexual

  11. The effectiveness of Stepping Stones Triple P: the design of a randomised controlled trial on a parenting programme regarding children with mild intellectual disability and psychosocial problems versus care as usual.

    Science.gov (United States)

    Kleefman, Marijke; Jansen, Daniëlle E M C; Reijneveld, Sijmen A

    2011-08-30

    Children with an intellectual disability are at increased risk of psychosocial problems. This leads to serious restrictions in the daily functioning of the children and to parental stress. Stepping Stones Triple P aims to prevent severe behavioural, emotional and developmental problems in children with a (intellectual) disability by enhancing parenting knowledge and skills, and the self-confidence of parents. This paper aims to describe the design of a study of the effectiveness of parenting counselling using Stepping Stones Triple P compared to Care as Usual. The effects of Stepping Stones Triple P will be studied in a Randomised Controlled Trial. Parents of children aged 5-12 years with an IQ of 50-85 will be recruited from schools. Prior to randomisation, parents complete a screening questionnaire about their child's psychosocial problems and their parenting skills. Subsequently, parents of children with increased levels of psychosocial problems (score on Strengths and Difficulties Questionnaire ≥ 14) will be invited to participate in the intervention study. After obtaining consent, parents will be randomised either to the experimental group (Stepping Stones Triple P) or to Care as Usual. The primary outcome is a change in the child's psychosocial problems according to parents and teachers. The secondary outcome is a change in parenting skills. Data will be collected before the start of the intervention, immediately after the intervention, and six months after. This paper presents an outline of the background and design of a randomised controlled trial to investigate the effectiveness of Stepping Stones Triple P, which aims to decrease psychosocial problems in children with a mild intellectual disability. Stepping Stones Triple P seems promising, but evidence on its effectiveness for this population is still lacking. This study provides evidence about the effects of this intervention in a community-based population of children with a mild intellectual

  12. Effects of disinfecting alginate impressions on the scratch hardness of stone models.

    Science.gov (United States)

    Hiraguchi, Hisako; Nakagawa, Hisami; Wakashima, Mitsuru; Miyanaga, Kohichi; Saigo, Masataka; Nishiyama, Minoru

    2006-03-01

    This study investigated the effects of disinfecting alginate impressions on the scratch depth of resultant stone models. Eleven brands of alginate impression material and two disinfectants, 1% sodium hypochlorite and 2% glutaraldehyde, were used. Impressions were immersed in disinfectant solutions or stored in sealed bags after spraying with disinfectants, and then poured with a type V dental stone. The scratch depth of the stone model obtained from disinfected impression was measured. The storage of alginate impressions after spraying with disinfectants did not increase the scratch depth of resultant stone models. However, the effect of immersion in disinfectants on scratch depth varied with the brand of the alginate impression material.

  13. Street based self-employment : a poverty trap or a stepping stone for migrant youth in Africa?

    OpenAIRE

    Bezu, Sosina; Holden, Stein Terje

    2015-01-01

    A significant percentage of youth in urban Africa is employed in the informal sector. The informal sector is more accessible than the formal sector for people with low human and financial capital, such as youth migrants from rural areas. But the sector is also generally considered to provide a subsistence livelihood. This study examines whether street based selfemployment in Africa offer a stepping stone towards a better livelihood or an urban poverty trap for youth migrants. The ana...

  14. The effectiveness of Stepping stones Triple P: the design of a randomised controlled trial on a parenting programme regarding children with mild intellectual disability and psychosocial problems versus care as usual

    Science.gov (United States)

    2011-01-01

    Background Children with an intellectual disability are at increased risk of psychosocial problems. This leads to serious restrictions in the daily functioning of the children and to parental stress. Stepping Stones Triple P aims to prevent severe behavioural, emotional and developmental problems in children with a (intellectual) disability by enhancing parenting knowledge and skills, and the self-confidence of parents. This paper aims to describe the design of a study of the effectiveness of parenting counselling using Stepping Stones Triple P compared to Care as Usual. Methods/Design The effects of Stepping Stones Triple P will be studied in a Randomised Controlled Trial. Parents of children aged 5-12 years with an IQ of 50-85 will be recruited from schools. Prior to randomisation, parents complete a screening questionnaire about their child's psychosocial problems and their parenting skills. Subsequently, parents of children with increased levels of psychosocial problems (score on Strengths and Difficulties Questionnaire ≥ 14) will be invited to participate in the intervention study. After obtaining consent, parents will be randomised either to the experimental group (Stepping Stones Triple P) or to Care as Usual. The primary outcome is a change in the child's psychosocial problems according to parents and teachers. The secondary outcome is a change in parenting skills. Data will be collected before the start of the intervention, immediately after the intervention, and six months after. Discussion This paper presents an outline of the background and design of a randomised controlled trial to investigate the effectiveness of Stepping Stones Triple P, which aims to decrease psychosocial problems in children with a mild intellectual disability. Stepping Stones Triple P seems promising, but evidence on its effectiveness for this population is still lacking. This study provides evidence about the effects of this intervention in a community-based population of

  15. The effectiveness of Stepping stones Triple P: the design of a randomised controlled trial on a parenting programme regarding children with mild intellectual disability and psychosocial problems versus care as usual

    Directory of Open Access Journals (Sweden)

    Jansen Daniëlle EMC

    2011-08-01

    Full Text Available Abstract Background Children with an intellectual disability are at increased risk of psychosocial problems. This leads to serious restrictions in the daily functioning of the children and to parental stress. Stepping Stones Triple P aims to prevent severe behavioural, emotional and developmental problems in children with a (intellectual disability by enhancing parenting knowledge and skills, and the self-confidence of parents. This paper aims to describe the design of a study of the effectiveness of parenting counselling using Stepping Stones Triple P compared to Care as Usual. Methods/Design The effects of Stepping Stones Triple P will be studied in a Randomised Controlled Trial. Parents of children aged 5-12 years with an IQ of 50-85 will be recruited from schools. Prior to randomisation, parents complete a screening questionnaire about their child's psychosocial problems and their parenting skills. Subsequently, parents of children with increased levels of psychosocial problems (score on Strengths and Difficulties Questionnaire ≥ 14 will be invited to participate in the intervention study. After obtaining consent, parents will be randomised either to the experimental group (Stepping Stones Triple P or to Care as Usual. The primary outcome is a change in the child's psychosocial problems according to parents and teachers. The secondary outcome is a change in parenting skills. Data will be collected before the start of the intervention, immediately after the intervention, and six months after. Discussion This paper presents an outline of the background and design of a randomised controlled trial to investigate the effectiveness of Stepping Stones Triple P, which aims to decrease psychosocial problems in children with a mild intellectual disability. Stepping Stones Triple P seems promising, but evidence on its effectiveness for this population is still lacking. This study provides evidence about the effects of this intervention in a community

  16. Specious causal attributions in the social sciences: the reformulated stepping-stone theory of heroin use as exemplar.

    Science.gov (United States)

    Baumrind, D

    1983-12-01

    The claims based on causal models employing either statistical or experimental controls are examined and found to be excessive when applied to social or behavioral science data. An exemplary case, in which strong causal claims are made on the basis of a weak version of the regularity model of cause, is critiqued. O'Donnell and Clayton claim that in order to establish that marijuana use is a cause of heroin use (their "reformulated stepping-stone" hypothesis), it is necessary and sufficient to demonstrate that marijuana use precedes heroin use and that the statistically significant association between the two does not vanish when the effects of other variables deemed to be prior to both of them are removed. I argue that O'Donnell and Clayton's version of the regularity model is not sufficient to establish cause and that the planning of social interventions both presumes and requires a generative rather than a regularity causal model. Causal modeling using statistical controls is of value when it compels the investigator to make explicit and to justify a causal explanation but not when it is offered as a substitute for a generative analysis of causal connection.

  17. Evaluation of Stepping Stones as a tool for changing knowledge, attitudes and behaviours associated with gender, relationships and HIV risk in Karnataka, India

    Directory of Open Access Journals (Sweden)

    Ramesh Banadakoppa M

    2011-06-01

    Full Text Available Abstract Background Stepping Stones training aims to help individuals explore sexual relationships and recognize gender inequalities, the structural drivers of the HIV epidemic, in order to understand risk behaviours and to seek solutions to factors that increase HIV vulnerability. Despite earlier studies suggesting the success of Stepping Stones, little data exist to show diffusion to trainees' social networks or the wider community. Methods A mixed-methods evaluation of this approach was undertaken using in-depth interviews of trainees and friends, and polling booth surveys in 20 villages where Stepping Stones training took place and in another 20 villages with no Stepping Stones intervention. Results The interview respondents and their friends reported significant changes in their relationships after training, and benefit from discussion of gender, sexuality, condom use and HIV vulnerability issues. However, though diffusion of this knowledge at the level of personal contacts was strong, the evaluation revealed that diffusion to the community level was limited. Conclusions The qualitative part of this study reflects other studies in different settings, in that SS participants gained immensely from the training. Wider behaviour change is a challenging goal that many programmes fail to attain, with most interventions too limited in scope and intensity to produce larger community effects. This may have contributed to the fact that we observed few differences between interventions and non-intervention villages in this study. However, it is also possible that we had excessive expectations of individual change at the community level, and that it might have been more appropriate to have had broader community level rather than individual behavioural change indicators. We suggest that SS could be enhanced by efforts to better engage existing community opinion leaders, to empower and train participants as community change agents, and to support the

  18. Anholt Rosetta Stones

    DEFF Research Database (Denmark)

    Trempe Jr., Robert B.; Buthke, Jan

    2017-01-01

    This book records and celebrates the research finding of Anholt Island by students from Studio 2B, Arkitektskolen Aarhus, These mahogany constructions are our architectural versions of a Rosetta Stone. These are constructs that record layers of information about Anholt island through virtual...... and physical techniques, where each step and mechanic imparts and inscribes knowledge beyond the 1:1. These constructs are visual keys, used to inspire and influence all decision-making processes in a design project. These architectural Rosetta Stones document and amplify quantitative information about a site...

  19. Modeling elastic wave propagation in kidney stones with application to shock wave lithotripsy.

    Science.gov (United States)

    Cleveland, Robin O; Sapozhnikov, Oleg A

    2005-10-01

    A time-domain finite-difference solution to the equations of linear elasticity was used to model the propagation of lithotripsy waves in kidney stones. The model was used to determine the loading on the stone (principal stresses and strains and maximum shear stresses and strains) due to the impact of lithotripsy shock waves. The simulations show that the peak loading induced in kidney stones is generated by constructive interference from shear waves launched from the outer edge of the stone with other waves in the stone. Notably the shear wave induced loads were significantly larger than the loads generated by the classic Hopkinson or spall effect. For simulations where the diameter of the focal spot of the lithotripter was smaller than that of the stone the loading decreased by more than 50%. The constructive interference was also sensitive to shock rise time and it was found that the peak tensile stress reduced by 30% as rise time increased from 25 to 150 ns. These results demonstrate that shear waves likely play a critical role in stone comminution and that lithotripters with large focal widths and short rise times should be effective at generating high stresses inside kidney stones.

  20. Stepping Stones Triple P: An RCT of a Parenting Program with Parents of a Child Diagnosed with an Autism Spectrum Disorder

    Science.gov (United States)

    Whittingham, Koa; Sofronoff, Kate; Sheffield, Jeanie; Sanders, Matthew R.

    2009-01-01

    Whilst the Triple P Positive Parenting Program has a large evidence base (Sanders, "Clinical Child and Family Psychology Review" 2:71-90, 1999; Sanders, "Journal of Consulting and Clinical Psychology" 68:624-640, 2000) and preliminary evidence indicates that Stepping Stones Triple P is also efficacious (Roberts, "Journal of Clinical Child and…

  1. Critical assessment of human metabolic pathway databases: a stepping stone for future integration

    Directory of Open Access Journals (Sweden)

    Stobbe Miranda D

    2011-10-01

    Full Text Available Abstract Background Multiple pathway databases are available that describe the human metabolic network and have proven their usefulness in many applications, ranging from the analysis and interpretation of high-throughput data to their use as a reference repository. However, so far the various human metabolic networks described by these databases have not been systematically compared and contrasted, nor has the extent to which they differ been quantified. For a researcher using these databases for particular analyses of human metabolism, it is crucial to know the extent of the differences in content and their underlying causes. Moreover, the outcomes of such a comparison are important for ongoing integration efforts. Results We compared the genes, EC numbers and reactions of five frequently used human metabolic pathway databases. The overlap is surprisingly low, especially on reaction level, where the databases agree on 3% of the 6968 reactions they have combined. Even for the well-established tricarboxylic acid cycle the databases agree on only 5 out of the 30 reactions in total. We identified the main causes for the lack of overlap. Importantly, the databases are partly complementary. Other explanations include the number of steps a conversion is described in and the number of possible alternative substrates listed. Missing metabolite identifiers and ambiguous names for metabolites also affect the comparison. Conclusions Our results show that each of the five networks compared provides us with a valuable piece of the puzzle of the complete reconstruction of the human metabolic network. To enable integration of the networks, next to a need for standardizing the metabolite names and identifiers, the conceptual differences between the databases should be resolved. Considerable manual intervention is required to reach the ultimate goal of a unified and biologically accurate model for studying the systems biology of human metabolism. Our comparison

  2. Fracture mechanics model of stone comminution in ESWL and implications for tissue damage

    Science.gov (United States)

    Lokhandwalla, Murtuza; Sturtevant, Bradford

    2000-07-01

    Focused shock waves administered during extracorporeal shock-wave lithotripsy (ESWL) cause stone fragmentation. The process of stone fragmentation is described in terms of a dynamic fracture process. As is characteristic of all brittle materials, fragmentation requires nucleation, growth and coalescence of flaws, caused by a tensile or shear stress. The mechanisms, operative in the stone, inducing these stresses have been identified as spall and compression-induced tensile microcracks, nucleating at pre-existing flaws. These mechanisms are driven by the lithotripter-generated shock wave and possibly also by cavitation effects in the surrounding fluid. In this paper, the spall mechanism has been analysed, using a cohesive-zone model for the material. The influence of shock wave parameters, and physical properties of stone, on stone comminution is described. The analysis suggests a potential means to exploit the difference between the stone and tissue physical properties, so as to make stone comminution more effective, without increasing tissue damage.

  3. The brush model - a new approach to numerical modeling of matrix diffusion in fractured clay stone

    International Nuclear Information System (INIS)

    Lege, T.; Shao, H.

    1998-01-01

    A special approach for numerical modeling of contaminant transport in fractured clay stone is presented. The rock matrix and the fractures are simulated with individual formulations for FE grids and transport, coupled into a single model. The capacity of the rock matrix to take up contaminants is taken into consideration with a discrete simulation of matrix diffusion. Thus, the natural process of retardation due to matrix diffusion can be better simulated than by a standard introduction of an empirical parameter into the transport equation. Transport in groundwater in fractured clay stone can be simulated using a model called a 'brush model'. The 'brush handle' is discretized by 2-D finite elements. Advective-dispersive transport in groundwater in the fractures is assumed. The contaminant diffuses into 1D finite elements perpendicular to the fractures, i.e., the 'bristles of the brush'. The conclusion is drawn that matrix diffusion is an important property of fractured clay stone for contaminant retardation. (author)

  4. Stepping Stones and Creating Futures intervention: shortened interrupted time series evaluation of a behavioural and structural health promotion and violence prevention intervention for young people in informal settlements in Durban, South Africa.

    Science.gov (United States)

    Jewkes, Rachel; Gibbs, Andrew; Jama-Shai, Nwabisa; Willan, Samantha; Misselhorn, Alison; Mushinga, Mildred; Washington, Laura; Mbatha, Nompumelelo; Skiweyiya, Yandisa

    2014-12-29

    Gender-based violence and HIV are highly prevalent in the harsh environment of informal settlements and reducing violence here is very challenging. The group intervention Stepping Stones has been shown to reduce men's perpetration of violence in more rural areas, but violence experienced by women in the study was not affected. Economic empowerment interventions with gender training can protect older women from violence, but microloan interventions have proved challenging with young women. We investigated whether combining a broad economic empowerment intervention and Stepping Stones could impact on violence among young men and women. The intervention, Creating Futures, was developed as a new generation of economic empowerment intervention, which enabled livelihood strengthening though helping participants find work or set up a business, and did not give cash or make loans. We piloted Stepping Stones with Creating Futures in two informal settlements of Durban with 232 out of school youth, mostly aged 18-30 and evaluated with a shortened interrupted time series of two baseline surveys and at 28 and 58 weeks post-baseline. 94/110 men and 111/122 women completed the last assessment, 85.5% and 90.2% respectively of those enrolled. To determine trend, we built random effects regression models with each individual as the cluster for each variable, and measured the slope of the line across the time points. Men's mean earnings in the past month increased by 247% from R411 (~$40) to R1015 (~$102, and women's by 278% R 174 (~$17) to R 484 (about $48) (trend test, p < 0.0001). There was a significant reduction in women's experience of the combined measure of physical and/or sexual IPV in the prior three months from 30.3% to 18.9% (p = 0.037). This was not seen for men. However both men and women scored significantly better on gender attitudes and men significantly reduced their controlling practices in their relationship. The prevalence of moderate or severe depression

  5. The moon as a stepping stone for a spacefaring civilization

    Science.gov (United States)

    Multhaup, K.

    2008-09-01

    After Columbia In early 2004, U.S. president George Bush introduced the Vision for Space Exploration (VSE). Conceived in the aftermath of the Columbia tragedy, it called for NASA to first return astronauts to the moon by 2020 and then send crews to Mars and beyond thereafter. Bush's plan has once again enlivened the long-lasting discussion of manned spaceflight vs. robotic exploration. Also, the plan to use the moon as a stepping stone has come under scrutiny and is being debated. Alternate approaches minimizing or deleting manned lunar exploration in the frame of the VSE were proposed. Fig. 1 A composite manned spacecraft departing Earth orbit en route to the moon. Image: NASA. In order to assess the value of us going back to the moon, it is necessary to debate without bias the meaning of human spaceflight in general and to discuss the role of science in future efforts. Lunar disenchantment Whithin the scientific community, manned exploration programs are put into question time and again. It is demanded that in light of supposedly immense costs any endeavour concerning this matter shall be justified by an indisputable scientific return — and in current debates, scientific value is not recognized in such a way that funding appears well-invested. It is lamented that funds are drawn from what is considered real science. In the past, robotic exploration has opended our eyes to the many wonders of the solar system. Through the eyes of Cassini , Mars Express, and other successful spacecraft, we have seen exotic landscapes—yet on second sight, some appeared all too familiar. BepiColombo will fly to Mercury to unravel its mysteries and the Jovian system may receive a new earthly visitor in the not too distant future. By means of machines like Spirit and Opportunity, we have roamed the surfaces of Mars—without actually ever setting foot there. Therefore, the question is often asked, "Why send crews?" Fig. 2 The upcoming Lunar Reconnisance Orbiter (LRO) as it circles

  6. CO2-driven Enhanced Oil Recovery as a Stepping Stone to What?

    Energy Technology Data Exchange (ETDEWEB)

    Dooley, James J.; Dahowski, Robert T.; Davidson, Casie L.

    2010-07-14

    This paper draws heavily on the authors’ previously published research to explore the extent to which near term carbon dioxide-driven enhanced oil recovery (CO2-EOR) can be “a stepping stone to a long term sequestration program of a scale to be material in climate change risk mitigation.” The paper examines the historical evolution of CO2-EOR in the United States and concludes that estimates of the cost of CO2-EOR production or the extent of CO2 pipeline networks based upon this energy security-driven promotion of CO2-EOR do not provide a robust platform for spurring the commercial deployment of carbon dioxide capture and storage technologies (CCS) as a means of reducing greenhouse gas emissions. The paper notes that the evolving regulatory framework for CCS makes a clear distinction between CO2-EOR and CCS and the authors examine arguments in the technical literature about the ability for CO2-EOR to generate offsetting revenue to accelerate the commercial deployment of CCS systems in the electric power and industrial sectors of the economy. The authors conclude that the past 35 years of CO2-EOR in the U.S. have been important for boosting domestic oil production and delivering proven system components for future CCS systems. However, though there is no reason to suggest that CO2-EOR will cease to deliver these benefits, there is also little to suggest that CO2-EOR is a necessary or significantly beneficial step towards the commercial deployment of CCS as a means of addressing climate change.

  7. Effect of immersion disinfection of alginate impressions in sodium hypochlorite solution on the dimensional changes of stone models.

    Science.gov (United States)

    Hiraguchi, Hisako; Kaketani, Masahiro; Hirose, Hideharu; Yoneyama, Takayuki

    2012-01-01

    This study investigated the effect of the immersion of alginate impressions in 0.5% sodium hypochlorite solution for 15 min on the dimensional changes of stone models designed to simulate a sectional form of a residual ridge. Five brands of alginate impression materials, which underwent various dimensional changes in water, were used. A stone model made with an impression that had not been immersed was prepared as a control. The immersion of two brands of alginate impressions that underwent small dimensional changes in water did not lead to serious deformation of the stone models, and the differences in the dimensional changes between the stone models produced with disinfected impressions and those of the control were less than 15 µm. In contrast, the immersions of three brands of alginate impressions that underwent comparatively large dimensional changes in water caused deformation of the stone models.

  8. The effectiveness of Stepping Stones Triple P parenting support in parents of children with borderline to mild intellectual disability and psychosocial problems : A randomized controlled trial

    NARCIS (Netherlands)

    Kleefman, Marijke; Jansen, Danielle E. M. C.; Stewart, Roy E.; Reijneveld, Sijmen A.

    2014-01-01

    Background: Children with borderline to mild intellectual disability (BMID) have been shown to be at increased risk for psychosocial problems. The presence of these psychosocial problems leads to parenting stress. Stepping Stones Triple P (SSTP) is a parenting support program to support parents with

  9. Everybody Must Get Stones

    Directory of Open Access Journals (Sweden)

    Timothy Darvill

    2009-09-01

    Full Text Available It is now widely recognised that monument building in the fourth and third millennia cal BC often involved transporting selected blocks of preferred stone many kilometres over difficult terrain. Some structures incorporated blocks from several different sources, brought together as an ensemble in much the same way perhaps that assemblages of flint and stone axes reflect both local and distant sources. This article explores alternative models accounting for the selection of stones, contrasting those that foreground symbolic attachments and imposed meanings with those that focus on the intrinsic qualities of particular types of stone and their source. The assemblage of different stone types that accumulated at Stonehenge, Wiltshire, over a period of more than a thousand years is used as a case study.

  10. Natural Stone in Spain: trends and perspectives

    International Nuclear Information System (INIS)

    Marchán Sanz, C.; Regueiro y González-Barros, M.; Delgado Arenas, P.

    2017-01-01

    The natural stone sector was severely affected by the national construction sector crisis. Production, both exworks and processed, has been also harshly affected dropping from 8Mt/y in 2007 to 3,49Mt/y in 2015, particularly in the marble and granite sectors, since slate has always been a mainly exporting sub-sector. In the latest times, thanks mainly to exports, production apparently has slowly started to recover. In this paper, we review the typology of the Spanish natural stone products and the production data of the main stone subsectors (marble, granite and slate) in the last 10 years and we review possible future trends in the framework of the first steps of the economic recovery. [es

  11. Stepping Stones through Time

    Directory of Open Access Journals (Sweden)

    Emily Lyle

    2012-03-01

    Full Text Available Indo-European mythology is known only through written records but it needs to be understood in terms of the preliterate oral-cultural context in which it was rooted. It is proposed that this world was conceptually organized through a memory-capsule consisting of the current generation and the three before it, and that there was a system of alternate generations with each generation taking a step into the future under the leadership of a white or red king.

  12. Pancreatic Stones: Treat or Ignore?

    Directory of Open Access Journals (Sweden)

    DA Howell

    1999-01-01

    Full Text Available Painful, chronic pancreatitis is of complex etiology, but increasing clinical experience suggests that removal of pancreatic duct stones in many cases significantly improves patients’ symptoms. The development and refinement of therapeutic endoscopic retrograde choledochopancreatography have permitted improved access to the pancreatic duct, which makes the development of new techniques of stone fragmentation and fragment removal a much more successful nonsurgical intervention. A major step forward has been the understanding of the safety and efficacy of pancreatic sphincterotomy, which is necessary for the removal of these difficult stones. The recognition that extracorporeal shock wave lithotripsy can be delivered safely with good efficacy has revolutionized the nonsurgical management of pancreatic duct stones. Nevertheless, advanced and sophisticated therapeutic endoscopy is necessary to achieve clearance of the duct, which can generally be accomplished in the majority of selected patients. State-of-the-art treatments are described, and some new approaches using pancreatoscopy and electrohydrolic lithotripsy are discussed. Newly recognized long term complications are reviewed. Finally, it must be recognized that chronic pancreatitis is an ongoing disease that does not have a simple treatment or cure, and frequently represents a process of remissions and relapses requiring interventions and problem solving.

  13. Three-dimensional evaluation of the repeatability of scans of stone models and impressions using a blue LED scanner.

    Science.gov (United States)

    Jeon, Jin-Hun; Jung, Il-Do; Kim, Ji-Hwan; Kim, Hae-Young; Kim, Woong-Chul

    2015-01-01

    In this study, we evaluated the repeatability of scans of stone models and impressions of abutment teeth using a blue LED scanner and compared the findings between different abutment teeth types. For the stone models as well as impression of the canines, premolars, and molars, we generated 10 color-difference-maps and reports for each tooth type (n=10 per tooth type). One-way analysis of variance (ANOVA) and independent t-tests were performed to evaluate the repeatability of scans of the stone models and impressions obtained from a blue LED scanner. Our results indicate a high repeatability of scans of stone models and impressions of abutment teeth using the blue LED scanner and suggest a possible clinical advantage for scanning impressions of different abutment teeth types.

  14. Fire effects on flaked stone, ground stone, and other stone artifacts [Chapter 4

    Science.gov (United States)

    Krista Deal

    2012-01-01

    Lithic artifacts can be divided into two broad classes, flaked stone and ground stone, that overlap depending on the defining criteria. For this discussion, flaked stone is used to describe objects that cut, scrape, pierce, saw, hack, etch, drill, or perforate, and the debris (debitage) created when these items are manufactured. Objects made of flaked stone include...

  15. Radiation exposure of patient and surgeon in minimally invasive kidney stone surgery.

    Science.gov (United States)

    Demirci, A; Raif Karabacak, O; Yalçınkaya, F; Yiğitbaşı, O; Aktaş, C

    2016-05-01

    Percutaneous nephrolithotomy (PNL) and retrograde intrarenal surgery (RIRS) are the standard treatments used in the endoscopic treatment of kidney stones depending on the location and the size of the stone. The purpose of the study was to show the radiation exposure difference between the minimally invasive techniques by synchronously measuring the amount of radiation the patients and the surgeon received in each session, which makes our study unique. This is a prospective study which included 20 patients who underwent PNL, and 45 patients who underwent RIRS in our clinic between June 2014 and October 2014. The surgeries were assessed by dividing them into three steps: step 1: the access sheath or ureter catheter placement, step 2: lithotripsy and collection of fragments, and step 3: DJ catheter or re-entry tube insertion. For the PNL and RIRS groups, mean stone sizes were 30mm (range 16-60), and 12mm (range 7-35); mean fluoroscopy times were 337s (range 200-679), and 37s (range 7-351); and total radiation exposures were 142mBq (44.7 to 221), and 4.4mBq (0.2 to 30) respectively. Fluoroscopy times and radiation exposures at each step were found to be higher in the PNL group compared to the RIRS group. When assessed in itself, the fluoroscopy time and radiation exposure were stable in RIRS, and the radiation exposure was the highest in step 1 and the lowest in step 3 in PNL. When assessed for the 19 PNL patients and the 12 RIRS patients who had stone sizes≥2cm, the fluoroscopy time in step 1, and the radiation exposure in steps 1 and 2 were found to be higher in the PNL group than the RIRS group (PPNL because it has short fluoroscopy time and the radiation exposure is low in every step. 4. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  16. Plausibiliteitsdocument STONE 2.0.Globale verkenning van de plausibiliteit van het model STONE versie 2.0 voor de modellering van uit -en afspoeling van N en P

    NARCIS (Netherlands)

    Overbeek GBJ; Beusen AHW; Boers PCM; Born GJ van den; Groenendijk P; Grinsven JJM; Kroon T; Meer HG van der; Oosterom HP; Puijenbroek PJTM van; Roelsma J; Roest CJW; Rotter R; Tiktak A; Tol S van; RIZA; Alterra; PRI; LBG; CIM; LAE; LWD

    2002-01-01

    The STONE model for N and P emission to groundwater and surface waters has been developed to evaluate the environmental benefits of eutrophication abatement plans. Due to possible severe socio-economic consequences of these abatement plans, it is of importance that the model is well documented,

  17. Clinical models are inaccurate in predicting bile duct stones in situ for patients with gallbladder.

    Science.gov (United States)

    Topal, B; Fieuws, S; Tomczyk, K; Aerts, R; Van Steenbergen, W; Verslype, C; Penninckx, F

    2009-01-01

    The probability that a patient has common bile duct stones (CBDS) is a key factor in determining diagnostic and treatment strategies. This prospective cohort study evaluated the accuracy of clinical models in predicting CBDS for patients who will undergo cholecystectomy for lithiasis. From October 2005 until September 2006, 335 consecutive patients with symptoms of gallstone disease underwent cholecystectomy. Statistical analysis was performed on prospective patient data obtained at the time of first presentation to the hospital. Demonstrable CBDS at the time of endoscopic retrograde cholangiopancreatography (ERCP) or intraoperative cholangiography (IOC) was considered the gold standard for the presence of CBDS. Common bile duct stones were demonstrated in 53 patients. For 35 patients, ERCP was performed, with successful stone clearance in 24 of 30 patients who had proven CBDS. In 29 patients, IOC showed CBDS, which were managed successfully via laparoscopic common bile duct exploration, with stone extraction at the time of cholecystectomy. Prospective validation of the existing model for CBDS resulted in a predictive accuracy rate of 73%. The new model showed a predictive accuracy rate of 79%. Clinical models are inaccurate in predicting CBDS in patients with cholelithiasis. Management strategies should be based on the local availability of therapeutic expertise.

  18. Probabilistic seismic vulnerability and risk assessment of stone masonry structures

    Science.gov (United States)

    Abo El Ezz, Ahmad

    Earthquakes represent major natural hazards that regularly impact the built environment in seismic prone areas worldwide and cause considerable social and economic losses. The high losses incurred following the past destructive earthquakes promoted the need for assessment of the seismic vulnerability and risk of the existing buildings. Many historic buildings in the old urban centers in Eastern Canada such as Old Quebec City are built of stone masonry and represent un-measurable architectural and cultural heritage. These buildings were built to resist gravity loads only and generally offer poor resistance to lateral seismic loads. Seismic vulnerability assessment of stone masonry buildings is therefore the first necessary step in developing seismic retrofitting and pre-disaster mitigation plans. The objective of this study is to develop a set of probability-based analytical tools for efficient seismic vulnerability and uncertainty analysis of stone masonry buildings. A simplified probabilistic analytical methodology for vulnerability modelling of stone masonry building with systematic treatment of uncertainties throughout the modelling process is developed in the first part of this study. Building capacity curves are developed using a simplified mechanical model. A displacement based procedure is used to develop damage state fragility functions in terms of spectral displacement response based on drift thresholds of stone masonry walls. A simplified probabilistic seismic demand analysis is proposed to capture the combined uncertainty in capacity and demand on fragility functions. In the second part, a robust analytical procedure for the development of seismic hazard compatible fragility and vulnerability functions is proposed. The results are given by sets of seismic hazard compatible vulnerability functions in terms of structure-independent intensity measure (e.g. spectral acceleration) that can be used for seismic risk analysis. The procedure is very efficient for

  19. Effect of stone coverage on soil erosion

    Science.gov (United States)

    Jomaa, S.; Barry, D. A.; Heng, B. P.; Brovelli, A.; Sander, G. C.; Parlange, J.

    2010-12-01

    Soil surface coverage has a significant impact on water infiltration, runoff and soil erosion yields. In particular, surface stones protect the soils from raindrop detachment, they retard the overland flow therefore decreasing its sediment transport capacity, and they prevent surface sealing. Several physical and environmental factors control to what extent stones on the soil surface modify the erosion rates and the related hydrological response. Among the most important factors are the moisture content of the topsoil, stone size, emplacement, coverage density and soil texture. Owing to the different inter-related processes, there is ambiguity concerning the quantitative effect of stones, and process-based understanding is limited. Experiments were performed (i) to quantify how stone features affect sediment yields, (ii) to understand the local effect of isolated surface stones, that is, the changes of the soil particle size distribution in the vicinity of a stone and (iii) to determine how stones attenuate the development of surface sealing and in turn how this affects the local infiltration rate. A series of experiments using the EPFL 6-m × 2-m erosion flume were conducted at different rainfall intensities (28 and 74 mm h-1) and stone coverage (20 and 40%). The total sediment concentration, the concentration of the individual size classes and the flow discharge were measured. In order to analyze the measurements, the Hairsine and Rose (HR) erosion model was adapted to account for the shielding effect of the stone cover. This was done by suitably adjusting the parameters based on the area not covered by stones. It was found that the modified HR model predictions agreed well with the measured sediment concentrations especially for the long time behavior. Changes in the bulk density of the topsoil due to raindrop-induced compaction with and without stone protection revealed that the stones protect the upper soil surface against the structural seals resulting in

  20. Villamayor stone (Golden Stone) as a Global Heritage Stone Resource from Salamanca (NW of Spain)

    Science.gov (United States)

    Garcia-Talegon, Jacinta; Iñigo, Adolfo; Vicente-Tavera, Santiago

    2013-04-01

    Villamayor stone is an arkosic stone of Middle Eocene age and belongs to the Cabrerizos Sandstone Formation that comprising braided fluvial systems and paleosoils at the top of each stratigraphic sequence. The sandstone is known by several names: i) the Villamayor Stone because the quarries are located in Villamayor de Armuña village that are situated at 7 km to the North from Salamanca city; ii) the Golden Stone due to its patina that produced a ochreous/golden color on the façades of monuments of Salamanca (World Heritage City,1988) built in this Natural stone (one of the silicated rocks utilised). We present in this work, the Villamayor Stone to be candidate as Global Heritage Stone Resource. The Villamayor Stone were quarrying for the construction and ornamentation of Romanesque religious monuments as the Old Cathedral and San Julian church; Gothic (Spanish plateresc style) as the New Cathedral, San Esteban church and the sculpted façade of the Salamanca University, one of the oldest University in Europe (it had established in 1250); and this stone was one of the type of one of the most sumptuous Baroque monuments is the Main Square of the its galleries and arcades (1729). Also, this stone was used in building palaces, walls and reconstruction of Roman bridge. Currently, Villamayor Stone is being quarried by small and family companies, without a modernized processing, for cladding of the façades of the new buildings until that the construction sector was burst (in 2008 the international economic crisis). However, Villamayor Stone is the main stone material used in the city of Salamanca for the restoration of monuments and, even in small quantities when compared with just before the economic crisis, it would be of great importance for future generations protect their quarries and the craft of masonry. Villamayor Stone has several varieties from channels facies to floodplains facies, in this work the selected varieties are: i) the fine-grained stone

  1. A study on the industrialization of building stones and industrial stone crafts - Study on the causes of stone contaminations

    Energy Technology Data Exchange (ETDEWEB)

    Hyun, Jeon Ki; Lee, Han Yeang [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1996-12-01

    Causes of building stone contamination are acid rains in polluted areas, iron bearing minerals in stone itself, salts, sealants, cutting and grinding processes in stone factory and steel compounds structures such as stone anchors, bolts, rain culvert and guide frames. Contaminations on the building stone surface of Sejong culture center can be found around floor stones, stair stones, parterre stones, pillar stones and other outdoor stone panels. The parterre stones are contaminated by white tarnishes and rust flows are occurred on the surface of pillar stones and outdoor stone panels around entrance. Black tarnishes are cumulated on the pillar stones and other outdoor decorated stone panels and change the original granite color. Causes of building stone contaminations from Sejong culture center are wet method to attach stone panels, rust from steel compounds structures and air pollutants. Cement and mortar used from wet method react with sulfur dioxides in polluted air and from fine calcite crystals (white tarnish). Rusts from steel compounds structures such as rainwater culvert and steel guide frames can move to the stone surface by rain and leave rust flows on it. Pollutants (tar compounds, carbons, dusts, etc.) in air are cumulated with humidity on the stone surface and change color from white granite color to dusty dark color. Historical stone sculptures such as man and animal shaped stone crafts, tombstones, square stone tables in front of a tomb and guide and circumference stones around tomb in Royal Tombs (Donggu rung, Yung rung, Seoou rung and Hunin rung) distributed in Kyunggi province are contaminated by various moss and air pollutants and its original colors are deeply changed. (author). 21 refs., 11 tabs., 22 figs.

  2. Bone Genes in the Kidney of Stone Formers

    Science.gov (United States)

    Evan, Andrew P.; Bledsoe, Sharon B.

    2008-09-01

    Intraoperative papillary biopsies from kidneys of idiopathic-calcium oxalate stone formers (ICSF) have revealed a distinct pattern of mineral deposition in the interstitium of the renal papilla. The earliest sites of these deposits, termed Randall's plaque, are found in the basement membrane of thin loops of Henle and appear to spread into the surrounding interstitium down to the papillary epithelium. Recent studies show kidney stones of ICSF patients grow attached to the renal papilla and at sites of Randall's plaque. Together these observations suggest that plaque formation may be the critical step in stone formation. In order to control plaque formation and thereby reduce future kidney stone development, the mechanism of plaque deposition must be understood. Because the renal papilla has unique anatomical features similar to bone and the fact that the interstitial deposits of ICSF patients are formed of biological apatite, this paper tests the hypothesis that sites of interstitial plaque form as a result of cell-mediated osteoblast-like activity.

  3. Effect of Tamsulosin on Stone Passage for Ureteral Stones: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Wang, Ralph C; Smith-Bindman, Rebecca; Whitaker, Evans; Neilson, Jersey; Allen, Isabel Elaine; Stoller, Marshall L; Fahimi, Jahan

    2017-03-01

    Tamsulosin is recommended for patients receiving a diagnosis of a ureteral stone less than 10 mm who do not require immediate urologic intervention. Because of conflicting results from recent meta-analyses and large randomized controlled trials, the efficacy of tamsulosin is unclear. We perform a systematic review and meta-analysis to investigate the effect of tamsulosin on stone passage in patients receiving a diagnosis of ureteral stone. MEDLINE, EMBASE, and CENTRAL databases were searched without language restriction through November 2015 for studies assessing the efficacy of tamsulosin and using a double-blind, randomized, controlled trial design. Meta-analysis was conducted with a random-effects model and subgroup analyses were conducted to determine sources of heterogeneity. Eight randomized controlled trials (N=1,384) contained sufficient information for inclusion. The pooled risk of stone passage in the tamsulosin arm was 85% versus 66% in the placebo arm, but substantial heterogeneity existed across trials (I 2 =80.2%; Ptamsulosin (risk difference=22%; 95% confidence interval 12% to 33%; number needed to treat=5). The meta-analysis of the small stone subgroup (Tamsulosin significantly improves stone passage in patients with larger stones, whereas the effect of tamsulosin is diminished in those with smaller stones, who are likely to pass their stone regardless of treatment. Copyright © 2016 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.

  4. From Catheter to Kidney Stone: The Uropathogenic Lifestyle of Proteus mirabilis.

    Science.gov (United States)

    Norsworthy, Allison N; Pearson, Melanie M

    2017-04-01

    Proteus mirabilis is a model organism for urease-producing uropathogens. These diverse bacteria cause infection stones in the urinary tract and form crystalline biofilms on indwelling urinary catheters, frequently leading to polymicrobial infection. Recent work has elucidated how P. mirabilis causes all of these disease states. Particularly exciting is the discovery that this bacterium forms large clusters in the bladder lumen that are sites for stone formation. These clusters, and other steps of infection, require two virulence factors in particular: urease and MR/P fimbriae. Highlighting the importance of MR/P fimbriae is the cotranscribed regulator, MrpJ, which globally controls virulence. Overall, P. mirabilis exhibits an extraordinary lifestyle, and further probing will answer exciting basic microbiological and clinically relevant questions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. A Drosophila genetic model of nephrolithiasis: transcriptional changes in response to diet induced stone formation.

    Science.gov (United States)

    Chung, Vera Y; Turney, Benjamin W

    2017-11-28

    Urolithiasis is a significant healthcare issue but the pathophysiology of stone disease remains poorly understood. Drosophila Malpighian tubules were known to share similar physiological function to human renal tubules. We have used Drosophila as a genetic model to study the transcriptional response to stone formation secondary to dietary manipulation. Wild-type male flies were raised on standard medium supplemented with lithogenic agents: control, sodium oxalate (NaOx) and ethylene glycol (EG). At 2 weeks, Malpighian tubules were dissected under polarized microscope to visualize crystals. The parallel group was dissected for RNA extraction and subsequent next-generation RNA sequencing. Crystal formation was visualized in 20%(±2.2) of flies on control diet, 73%(±3.6) on NaOx diet and 84%(±2.2) on EG diet. Differentially expressed genes were identified in flies fed with NaOx and EG diet comparing with the control group. Fifty-eight genes were differentially expressed (FDR <0.05, p < 0.05) in NaOx diet and 20 genes in EG diet. The molecular function of differentially expressed genes were assessed. Among these, Nervana 3, Eaat1 (Excitatory amino acid transporter 1), CG7912, CG5404, CG3036 worked as ion transmembrane transporters, which were possibly involved in stone pathogenesis. We have shown that by dietary modification, stone formation can be manipulated and visualized in Drosophila Malpighian tubules. This genetic model could be potentially used to identify the candidate genes that influence stone risk hence providing more insight to the pathogenesis of human stone disease.

  6. Electric Road Systems: Strategic Stepping Stone on the Way towards Sustainable Freight Transport?

    Directory of Open Access Journals (Sweden)

    Jesko Schulte

    2018-04-01

    Full Text Available Electrification of the transport sector has been pointed out as a key factor for tackling some of today’s main challenges, such as global warming, air pollution, and eco-system degradation. While numerous studies have investigated the potential of electrifying passenger transport, less focus has been on how road freight transport could be powered in a sustainable future. This study looks at Electric Road Systems (ERS in comparison to the current diesel system. The Framework for Strategic Sustainable Development was used to assess whether ERS could be a stepping stone on the way towards sustainability. Strategic life-cycle assessment was applied, scanning each life-cycle phase for violations against basic sustainability principles. Resulting sustainability “hot spots” were quantified with traditional life-cycle assessment. The results show that, if powered by renewable energy, ERS have a potential to decrease the environmental impact of freight transport considerably. Environmental payback times of less than five years are achievable if freight traffic volumes are sufficiently high. However, some severe violations against sustainability principles were identified. Still, ERS could prove to be a valuable part of the solution, as they drastically decrease the need for large batteries with high cost and sustainability impact, thereby catalyzing electrification and the transition towards sustainable freight transport.

  7. Numerical modelling techniques of soft soil improvement via stone columns: A brief review

    Science.gov (United States)

    Zukri, Azhani; Nazir, Ramli

    2018-04-01

    There are a number of numerical studies on stone column systems in the literature. Most of the studies found were involved with two-dimensional analysis of the stone column behaviour, while only a few studies used three-dimensional analysis. The most popular software utilised in those studies was Plaxis 2D and 3D. Other types of software that used for numerical analysis are DIANA, EXAMINE, ZSoil, ABAQUS, ANSYS, NISA, GEOSTUDIO, CRISP, TOCHNOG, CESAR, GEOFEM (2D & 3D), FLAC, and FLAC 3. This paper will review the methodological approaches to model stone column numerically, both in two-dimensional and three-dimensional analyses. The numerical techniques and suitable constitutive model used in the studies will also be discussed. In addition, the validation methods conducted were to verify the numerical analysis conducted will be presented. This review paper also serves as a guide for junior engineers through the applicable procedures and considerations when constructing and running a two or three-dimensional numerical analysis while also citing numerous relevant references.

  8. Evaluation of Extracorporeal Shock Wave Lithotripsy (ESWL): Efficacy in Treatment of Urinary System Stones.

    Science.gov (United States)

    Junuzovic, Dzelaludin; Prstojevic, Jelena Kovacevic; Hasanbegovic, Munira; Lepara, Zahid

    2014-10-01

    Elimination of stone is determined by size and its localization. Stone from the ureter in 80% of cases can be eliminated spontaneously. If the stone by its characteristics is not spontaneously eliminated, taken are further steps and therapeutic protocols to solve this problem. The study was prospective, open and comparative. It was conducted at the Urology Clinic Clinical Center of Sarajevo University in the period from 2007 to 2013. The study included 404 patients with urinary tract lithiasis treated by ESWL. ESWL treatment is performed on the machine Siemens Model Lithostar Multiline, which has a combined ultrasonographic and fluoroscopic display, large energy density in order to obtain optimum focus (without damaging surrounding tissue) and minimal pain that on rare occasions requires for mild sedation-sedation. From a total of 404 patients included in the study there were 234 (57.92%) male and 170 (42.08%) female patients. The most common type of stone both in female and male patients was calcium type. From a total of 262 calcium stones, 105 of them (40.07%) was present in female patients and 157 (59.92%) in male. Share of infectious type of stone in female patients was 63 (49.60%) and 64 among males (50.39%). Other stones were less abundant in both the gender groups and their total number was only 17. In women their frequency was 2 (13.33%) and 13 among males (86.67%). There was a significant difference in the frequency of different types of stones by gender (x2 = 11.47, p = 0.009). There was no statistically significant correlation between the number of treatments and localization of stones in the ureter, as well as a statistically significant correlation between the size of the stone and the localization of calculus in the ureter.

  9. The effectiveness of Stepping stones Triple P : the design of a randomised controlled trial on a parenting programme regarding children with mild intellectual disability and psychosocial problems versus care as usual

    NARCIS (Netherlands)

    Kleefman, Marijke; Jansen, Danielle E. M. C.; Reijneveld, Sijmen A.

    2011-01-01

    Background: Children with an intellectual disability are at increased risk of psychosocial problems. This leads to serious restrictions in the daily functioning of the children and to parental stress. Stepping Stones Triple P aims to prevent severe behavioural, emotional and developmental problems

  10. Assessment of stone composition in the management of urinary stones

    NARCIS (Netherlands)

    Kijvikai, Kittinut; de la Rosette, J. J. M.

    2011-01-01

    Several explanations have been suggested to account for the failure of extracorporeal shockwave lithotripsy (ESWL) treatment in patients with urinary stones, including large stone volume, unfavorable stone location or composition and the type of lithotriptor used. Unfavorable stone composition is

  11. Infection (urease) stones.

    Science.gov (United States)

    Griffith, D P; Osborne, C A

    1987-01-01

    Infection-induced stones in man probably form solely as a consequence of urealysis which is catalyzed by the bacterial protein urease. Urease stones composed of struvite and carbonate-apatite may form primarily, or as secondary stones or pre-existent metabolic stones. Struvite stones form and grow rapidly owing to (a) supersaturation of urine with stone forming salts, (b) 'salting out' of poorly soluble organic substances normally dissolved in urine and (c) ammonia-induced destruction of the normally protective urothelial glycosaminoglycan layer. Immature (predominantly organic) matrix stones mature into densely mineralized stones. Curative treatment is possible only by eliminating all of the stone and by eradicating all urinary and parenchymal infection. A variety of operative and pharmaceutical approaches are available. Patient treatment must be individualized inasmuch as some patients are better candidates for one type of treatment than another.

  12. Comparison of dimensional accuracy of digital dental models produced from scanned impressions and scanned stone casts

    Science.gov (United States)

    Subeihi, Haitham

    Introduction: Digital models of dental arches play a more and more important role in dentistry. A digital dental model can be generated by directly scanning intraoral structures, by scanning a conventional impression of oral structures or by scanning a stone cast poured from the conventional impression. An accurate digital scan model is a fundamental part for the fabrication of dental restorations. Aims: 1. To compare the dimensional accuracy of digital dental models produced by scanning of impressions versus scanning of stone casts. 2. To compare the dimensional accuracy of digital dental models produced by scanning of impressions made of three different materials (polyvinyl siloxane, polyether or vinyl polyether silicone). Methods and Materials: This laboratory study included taking addition silicone, polyether and vinyl polyether silicone impressions from an epoxy reference model that was created from an original typodont. Teeth number 28 and 30 on the typodont with a missing tooth number 29 were prepared for a metal-ceramic three-unit fixed dental prosthesis with tooth #29 being a pontic. After tooth preparation, an epoxy resin reference model was fabricated by duplicating the typodont quadrant that included the tooth preparations. From this reference model 12 polyvinyl siloxane impressions, 12 polyether impressions and 12 vinyl polyether silicone impressions were made. All 36 impressions were scanned before pouring them with dental stone. The 36 dental stone casts were, in turn, scanned to produce digital models. A reference digital model was made by scanning the reference model. Six groups of digital models were produced. Three groups were made by scanning of the impressions obtained with the three different materials, the other three groups involved the scanning of the dental casts that resulted from pouring the impressions made with the three different materials. Groups of digital models were compared using Root Mean Squares (RMS) in terms of their

  13. Prediction of the Effect of Using Stone Column in Clayey Soil on the Behavior of Circular Footing by ANN Model

    Directory of Open Access Journals (Sweden)

    Omar Khaleel Ismael Al-Kubaisi

    2018-05-01

    Full Text Available Shallow foundations are usually used for structures with light to moderate loads where the soil underneath can carry them. In some cases, soil strength and/or other properties are not adequate and require improvement using one of the ground improvement techniques. Stone column is one of the common improvement techniques in which a column of stone is installed vertically in clayey soils. Stone columns are usually used to increase soil strength and to accelerate soil consolidation by acting as vertical drains. Many researches have been done to estimate the behavior of the improved soil. However, none of them considered the effect of stone column geometry on the behavior of the circular footing. In this research, finite element models have been conducted to evaluate the behavior of a circular footing with different stone column configurations. Moreover, an Artificial Neural Network (ANN model has been generated for predicting these effects. The results showed a reduction in the bending moment, the settlement, and the vertical stresses with the increment of the stone column length, while both the horizontal stress and the shear force were increased. ANN model showed a good relationship between the predicted and the calculated results.

  14. Pitfalls in urinary stone identification using CT attenuation values: Are we getting the same information on different scanner models?

    Energy Technology Data Exchange (ETDEWEB)

    Grosjean, Romain, E-mail: r.grosjean@chu-nancy.fr [IADI Laboratory, INSERM-U947, Nancy-University, Allée du Morvan, 54500 Vandoeuvre-les-Nancy (France); Daudon, Michel, E-mail: michel.daudon@tnn.aphp.fr [IADI Laboratory, INSERM-U947, Nancy-University, Allée du Morvan, 54500 Vandoeuvre-les-Nancy (France); Chammas, Mario F., E-mail: mariochammas@usp.br [University of Sao Paulo – Division of Urology, Av. Dr. Enéas de Carvalho Aguiar, 255, 7" o Andar – s. 7123, São Paulo (Brazil); Claudon, Michel, E-mail: m.claudon@chu-nancy.fr [IADI Laboratory, INSERM-U947, Nancy-University, Allée du Morvan, 54500 Vandoeuvre-les-Nancy (France); Eschwege, Pascal, E-mail: peschwege@yahoo.com [Department of Urology, Brabois Hospital, University Hospital of Nancy, Allée du Morvan, 54511 Vandoeuvre-les-Nancy (France); Felblinger, Jacques, E-mail: j.felblinger@chu-nancy.fr [IADI Laboratory, INSERM-U947, Nancy-University, Allée du Morvan, 54500 Vandoeuvre-les-Nancy (France); Hubert, Jacques, E-mail: j.hubert@chu-nancy.fr [Department of Urology, Brabois Hospital, University Hospital of Nancy, Allée du Morvan, 54511 Vandoeuvre-les-Nancy (France)

    2013-08-15

    Introduction: Evaluate the capability of different Computed Tomography scanners to determine urinary stone compositions based on CT attenuation values and to evaluate potential differences between each model. Methods: 241 human urinary stones were obtained and their biochemical composition determined. Four different CT scanners (Siemens, Philips, GEMS and Toshiba) were evaluated. Mean CT-attenuation values and the standard deviation were recorded separately and compared with a t-paired test. Results: For all tested CT scanners, when the classification of the various types of stones was arranged according to the mean CT-attenuation values and to the confidence interval, large overlappings between stone types were highlighted. The t-paired test showed that most stone types could not be identified. Some types of stones presented mean CT attenuation values significantly different from one CT scanner to another. At 80 kV, the mean CT attenuation values obtained with the Toshiba Aquilion were significantly different from those obtained with the Siemens Sensation. On the other hand, mean values obtained with the Philips Brilliance were all significantly equal to those obtained with the Siemens Sensation and with the Toshiba Aquilion. At 120 kV mean CT attenuation values of uric acid, cystine and struvite stones obtained with the Philips model are significantly different from those obtained with the Siemens and the Toshiba but equal to those obtained with the GE 64. Conclusions: According to our study, there is a great variability when different brands and models of scanners are compared directly. Furthermore, the CT scan analysis and HU evaluation appears to gather insufficient information in order to characterize and identify the composition of renal stones.

  15. Pitfalls in urinary stone identification using CT attenuation values: Are we getting the same information on different scanner models?

    International Nuclear Information System (INIS)

    Grosjean, Romain; Daudon, Michel; o Andar – s. 7123, São Paulo (Brazil))" data-affiliation=" (University of Sao Paulo – Division of Urology, Av. Dr. Enéas de Carvalho Aguiar, 255, 7o Andar – s. 7123, São Paulo (Brazil))" >Chammas, Mario F.; Claudon, Michel; Eschwege, Pascal; Felblinger, Jacques; Hubert, Jacques

    2013-01-01

    Introduction: Evaluate the capability of different Computed Tomography scanners to determine urinary stone compositions based on CT attenuation values and to evaluate potential differences between each model. Methods: 241 human urinary stones were obtained and their biochemical composition determined. Four different CT scanners (Siemens, Philips, GEMS and Toshiba) were evaluated. Mean CT-attenuation values and the standard deviation were recorded separately and compared with a t-paired test. Results: For all tested CT scanners, when the classification of the various types of stones was arranged according to the mean CT-attenuation values and to the confidence interval, large overlappings between stone types were highlighted. The t-paired test showed that most stone types could not be identified. Some types of stones presented mean CT attenuation values significantly different from one CT scanner to another. At 80 kV, the mean CT attenuation values obtained with the Toshiba Aquilion were significantly different from those obtained with the Siemens Sensation. On the other hand, mean values obtained with the Philips Brilliance were all significantly equal to those obtained with the Siemens Sensation and with the Toshiba Aquilion. At 120 kV mean CT attenuation values of uric acid, cystine and struvite stones obtained with the Philips model are significantly different from those obtained with the Siemens and the Toshiba but equal to those obtained with the GE 64. Conclusions: According to our study, there is a great variability when different brands and models of scanners are compared directly. Furthermore, the CT scan analysis and HU evaluation appears to gather insufficient information in order to characterize and identify the composition of renal stones

  16. Do Parental Attributions Affect Treatment Outcome in a Parenting Program? An Exploration of the Effects of Parental Attributions in an RCT of Stepping Stones Triple P for the ASD Population

    Science.gov (United States)

    Whittingham, Koa; Sofronoff, Kate; Sheffield, Jeanie; Sanders, Matthew R.

    2009-01-01

    This study was conducted in conjunction with a randomised controlled trial of the parenting program Stepping Stones Triple P for parents of children with autism spectrum disorders (ASDs). Fifty-nine families with a child with ASD participated. This study focussed upon the role of parental attributions in predicting treatment outcome. Stepping…

  17. Experiments on the role of deleterious mutations as stepping stones in adaptive evolution

    Science.gov (United States)

    Covert, Arthur W.; Lenski, Richard E.; Wilke, Claus O.; Ofria, Charles

    2013-01-01

    Many evolutionary studies assume that deleterious mutations necessarily impede adaptive evolution. However, a later mutation that is conditionally beneficial may interact with a deleterious predecessor before it is eliminated, thereby providing access to adaptations that might otherwise be inaccessible. It is unknown whether such sign-epistatic recoveries are inconsequential events or an important factor in evolution, owing to the difficulty of monitoring the effects and fates of all mutations during experiments with biological organisms. Here, we used digital organisms to compare the extent of adaptive evolution in populations when deleterious mutations were disallowed with control populations in which such mutations were allowed. Significantly higher fitness levels were achieved over the long term in the control populations because some of the deleterious mutations served as stepping stones across otherwise impassable fitness valleys. As a consequence, initially deleterious mutations facilitated the evolution of complex, beneficial functions. We also examined the effects of disallowing neutral mutations, of varying the mutation rate, and of sexual recombination. Populations evolving without neutral mutations were able to leverage deleterious and compensatory mutation pairs to overcome, at least partially, the absence of neutral mutations. Substantially raising or lowering the mutation rate reduced or eliminated the long-term benefit of deleterious mutations, but introducing recombination did not. Our work demonstrates that deleterious mutations can play an important role in adaptive evolution under at least some conditions. PMID:23918358

  18. One-step laparoscopic and endoscopic treatment of gallbladder and common bile duct stones: our experience of the last 9 years in a retrospective study.

    Science.gov (United States)

    Liverani, Andrea; Muroni, Mirko; Santi, Francesco; Neri, Tiziano; Anastasio, Gerardo; Moretti, Marco; Favi, Francesco; Solinas, Luigi

    2013-12-01

    The optimal timing and best method for removal of common bile duct stones (CBDS) associated with gallbladder stones (GBS) is still controversial. The aim of this study is to investigate the outcomes of a single-step procedure combining laparoscopic cholecystectomy (LC), intraoperative cholangiography (IOC), and endoscopic retrograde cholangiopancreatography (ERCP). Between January 2003 and January 2012, 1972 patients underwent cholecystectomy at our hospital. Of those, 162 patients (8.2%; male/female 72/90) presented with GBS and suspected CBDS. We treated 54 cases (Group 1) with ERCP and LC within 48 to 72 hours. In 108 patients (Group 2) we performed LC with IOC and, if positive, was associated with IO-ERCP and sphincterotomy. In Group 1, a preoperative ERCP and LC were completed in 50 patients (30%). In four cases (2%), an ERCP and endobiliary stents were performed without cholecystectomy and then patients were discharged because of the severity of clinical conditions and advanced American Society of Anesthesiologists score (III to IV). Two months later a preoperative ERCP and removal of biliary stents were performed followed by LC 48 to 72 hours later. In Group 2, the IOC was performed in all cases and CBDS were extracted in 94 patients (87%). In two cases, the laparoscopic choledochotomy was necessary to remove large stones. In another two cases, an open choledochotomy was performed to remove safely the stones with T-tube drainage. In three cases, conversion was necessary to safely complete the procedure. The mean operative time was 95 minutes (range, 45 to 150 minutes) in Group 1 and 130 minutes (range, 50 to 300 minutes) in Group 2. The mean hospital stay was 6.5 days (range, 4 to 21 days) in Group 1 and 4.7 days (range, 3 to 14 days) in Group 2. Five cases (two in Group 2 and three in Group 1) presented with CBDS at 12 to 18 months after surgery. They were treated successfully with a second ERCP. There was no perioperative mortality. Our experience suggests

  19. Quantifying the Use of stones in the stone age Fireplaces of Estonia

    OpenAIRE

    Sikk, Kaarel

    2017-01-01

    Fireplaces and burnt stones related to them are common features found at Stone Age settlement sites. Although information about them is present in archaeological reports and also available in publications, there has been no general research done regarding combustion features specifically. The purpose of this study was to fill the gap of relevant research and to test the hypothesis that the structural features of fireplaces reveal information on the subsistence model of settlements.The study is b...

  20. Do stone size and impaction influence therapeutic approach to proximal ureteral stones?

    Directory of Open Access Journals (Sweden)

    Radulović Slobodan

    2009-01-01

    Full Text Available Background/Aim. Primary therapeutic approach to lumbar ureteral stones is still contraversial. The aim of the study was to investigate the influence of stone impaction and size on the effectiveness of proximal ureteral stone lithotripsy. Methods. A total of 123 patients with proximal ureteral stones were investigated in this prospective study performed in a 10- month period. The patients were divided into the group I - 86 patients treated with extracorporeal shock wave lithotripsy (ESWL and the group II - 37 patients treated with 'Swiss' Lithoclast. In the group I, 49 stones (57% were classified as impacted, while 20 stones (23.3% were larger than 100 mm2. In the group II, 26 stones (70.3% were impacted, and 11 stones (29.7% were larger than 100 mm2. Stones were defined as impacted by the radiographic, echosonographic as well as endoscopic findings in the group II of patients. Stone size was presented in mm2. Chemical composition of stones were almost the same in both groups of the patients. Results. Generally, there was no statistically significant difference in the treatment success between the groups. However, stones larger than 100 mm2 were statistically more successfully treated endoscopically, while there was no statistical difference in the treatment success of impacted stones between these two groups. Conclusion. ESWL can by considered as primary first therapeutic approach in treatment of all proximal ureteral stones except for stones larger than 100 mm2 that should primarily be treated endoscopically.

  1. Open stone surgery: a still-in-use approach for complex stone burden.

    Science.gov (United States)

    Çakici, Özer Ural; Ener, Kemal; Keske, Murat; Altinova, Serkan; Canda, Abdullah Erdem; Aldemir, Mustafa; Ardicoglu, Arslan

    2017-06-30

    Urinary stone disease is a major urological condition. Endourologic techniques have influenced the clinical approach and outcomes. Open surgery holds a historic importance in the management of most conditions. However, complex kidney stone burden may be amenable to successful results with open stone surgery. In this article, we report our eighteen cases of complex urinary stone disease who underwent open stone removal. A total of 1701 patients have undergone surgical treatment for urinary stone disease in our clinic between July 2012 and July 2016, comprising eighteen patients who underwent open stone surgery. Patients' demographic data, stone analysis results, postoperative clinical data, and stone status were evaluated retrospectively. The choice of surgical approach is mostly dependent on the surgeon's preference. In two patients, open surgery was undertaken because of perioperative complications. We did not observe any Clavien-Dindo grade 4 or 5 complications. Three patients were managed with a course of antibiotics due to postoperative fever. One patient had postoperative pleurisy, one patient had urinoma, and two patients had postoperative ileus. Mean operation time was 84 (57-124) minutes and mean hospitalization time was 5.5 (3-8) days. Stone-free status was achieved in 15 patients (83.3%). Endourologic approaches are the first options for treatment of urinary stone disease. However, open stone surgery holds its indispensable position in complicated cases and in complex stone burden. Open stone surgery is also a valid alternative to endourologic techniques in all situations.

  2. Development methodology of the novel Endoscopic stone treatment step 1 (EST s1) training/assessment curriculum.

    Science.gov (United States)

    Veneziano, Domenico; Ahmed, Kamran; Van Cleynenbreugel, Ben S E P; Gözen, Ali Serdar; Palou, Joan; Sarica, Kemal; Liatsikos, Evangelos N; Sanguedolce, Francesco; Honeck, Patrick; Alvarez-Maestro, Mario; Papatsoris, Athanasios; Kallidonis, Panagiotis; Greco, Francesco; Breda, Alberto; Somani, Bhaskar

    2017-07-10

    Background Simulation based technical-skill assessment is a core topic of debate, especially in high-risk environments. After the introduction of the E-BLUS exam for basic laparoscopy, no more technical training/assessment urological protocols have been developed in Europe. Objective We describe the methodology used in the development of the novel Endoscopic Stone Treatment step 1 (EST s1) assessment curriculum. Materials and Methods The "full life cycle curriculum development" template was followed for curriculum development. A CTA was run to define the most important steps and details of RIRS, in accordance with EAU Urolithiasis guidelines. Training tasks were created between April 2015 and September 2015. Tasks and metrics were further analyzed by a consensus meeting with the EULIS board in February 2016. A review, aimed to study available simulators and their accordance with task requirements, was subsequently run in London on March 2016. After initial feedback and further tests, content validity of this protocol was achieved during EUREP 2016. Results The EST s1 curriculum development, took 23 months. 72 participants tested the 5 preliminary tasks during EUREP 2015, with sessions of 45 minutes each. Likert-scale questionnaires were filled-out to score the quality of training. The protocol was modified accordingly and 25 participants tested the 4 tasks during the hands-on training sessions of the ESUT 2016 congress. 134 participants finally participated in the validation study in EUREP 2016. During the same event 10 experts confirmed content validity by filling-out a Likert-scale questionnaire. Conclusion We described a reliable and replicable methodology that can be followed to develop training/assessment protocols for surgical procedures. The expert consensus meetings, strict adherence to guidelines and updated literature search towards an Endourology curriculum allowed correct training and assessment protocol development. It is the first step towards

  3. Contribution of stone size to chronic kidney disease in kidney stone formers.

    Science.gov (United States)

    Ahmadi, Farrokhlagha; Etemadi, Samira Motedayen; Lessan-Pezeshki, Mahbob; Mahdavi-Mazdeh, Mitra; Ayati, Mohsen; Mir, Alireza; Yazdi, Hadi Rokni

    2015-01-01

    To determine whether stone burden correlates with the degree of chronic kidney disease in kidney stone formers. A total of 97 extracorporeal shockwave lithotripsy candidates aged 18 years and older were included. Size, number and location of the kidney stones, along with cumulative stone size, defined as the sum of diameters of all stones) were determined. Estimated glomerular filtration rate was determined using the Chronic Kidney Disease Epidemiology Collaboration cystatin C/creatinine equation, and chronic kidney disease was defined as estimated glomerular filtration rate chronic kidney disease. The relationship persisted even after adjustment for age, sex, body mass index, C-reactive protein, fasting plasma glucose, thyroid stimulating hormone, presence of microalbuminuria, history of renal calculi, history of extracorporeal shockwave lithotripsy, number and location of the stones (odds ratio 1.24, 95% confidence interval 1.02-1.52). The same was not observed for individuals with a cumulative stone size ≥ 20 mm. In kidney stone formers with a cumulative stone size up to 20 mm, estimated glomerular filtration rate linearly declines with increasing cumulative stone size. Additionally, cumulative stone size is an independent predictor of chronic kidney disease in this group of patients. © 2014 The Japanese Urological Association.

  4. Bath Stone - a Possible Global Heritage Stone from England

    Science.gov (United States)

    Marker, Brian

    2014-05-01

    The Middle Jurassic strata of England have several horizons of oolitic and bioclastic limestones that provide high quality dimension stone. One of the most important is found in and near the City of Bath. The Great Oolite Group (Upper Bathonian) contains the Combe Down and Bath Oolites, consisting of current bedded oolites and shelly oolites, that have been used extensively as freestones for construction nearby, for prestigious buildings through much of southern England and more widely. The stone has been used to some extent since Roman times when the city, then known as Aquae Sulis, was an important hot spa. The stone was used to a limited extent through medieval times but from the early 18th century onwards was exploited on a large scale through surface quarrying and underground mining. The City was extensively redeveloped in the 18th to early 19th century, mostly using Bath Stone, when the spas made it a fashionable resort. Buildings from that period include architectural "gems" such as the Royal Crescent and Pulteney Bridge, as well as the renovated Roman Baths. Many buildings were designed by some of the foremost British architects of the time. The consistent use of this stone gives the City an architectural integrity throughout. These features led to the designation of the City as a World Heritage Site. It is a requirement in current City planning policy documents that Bath Stone should be used for new building to preserve the appearance of the City. More widely the stone was used in major houses (e.g. Buckingham Palace and Apsley House in London; King's Pavilion in Brighton); civic buildings (e.g. Bristol Guildhall; Dartmouth Naval College in Devon); churches and cathedrals (e.g. Truro Cathedral in Cornwall); and engineered structures (e.g. the large Dundas Aqueduct on the Kennet and Avon Canal). More widely, Bath Stone has been used in Union Station in Washington DC; Toronto Bible College and the Town Hall at Cape Town, South Africa. Extraction declined in

  5. The effectiveness of Stepping Stones Triple P parenting support in parents of children with borderline to mild intellectual disability and psychosocial problems: a randomized controlled trial

    OpenAIRE

    Kleefman, Marijke; Jansen, Daniëlle EMC; Stewart, Roy E; Reijneveld, Sijmen A

    2014-01-01

    Background Children with borderline to mild intellectual disability (BMID) have been shown to be at increased risk for psychosocial problems. The presence of these psychosocial problems leads to parenting stress. Stepping Stones Triple P (SSTP) is a parenting support program to support parents with children with BMID and psychosocial problems. The aim of this study was to evaluate the effectiveness of SSTP compared to Care as Usual (CAU) in reducing psychosocial problems in children with BMID...

  6. Isotopic and microbial indicators of sewage pollution from Stone Town, Zanzibar, Tanzania

    International Nuclear Information System (INIS)

    Moynihan, Molly A.; Baker, David M.; Mmochi, Aviti J.

    2012-01-01

    In Stone Town, Zanzibar, sewage treatment is minimal, with a biological oxygen demand reduction to 60% and no removal of bacteria or nutrients. Here, Stone Town’s sewage pollution was studied by measuring Enterococci and NH 4 + concentrations in seawater and δ 15 N of benthic organisms; samples were collected along the Stone Town shoreline and from offshore coral reefs. Public perceptions of sewage pollution were investigated via interviews. Enterococci from the Stone Town shoreline exceeded USEPA guidelines for recreational use. Benthic organisms from two of the four reefs were relatively enriched (δ 15 N > 10‰), indicative of sewage derived N. δ 15 N values of organisms from Stone Town exceeded 16‰. A strong correlation was found between Enterococci and δ 15 N across sites, while step-wise regression indicated rainfall and tidal stage as important predictors for bacterial concentrations. These data provide an important impact assessment from which the efficacy of future policy and management change can be assessed.

  7. Numerical simulation of the time-dependent deformation behaviour of clay-stone rock mass at the Tournemire site with 2D and 3D models

    International Nuclear Information System (INIS)

    Rutenberg, M.; Lux, K.H.

    2010-01-01

    deformations, and/or; - effects from various hydraulic or hydro-mechanical influences on the saturated rock mass after excavation, such as: - changes of pore pressure (inducing consolidation) and water content (desaturation and re-saturation, due to evaporation/condensation/sorption processes), - shrinking/swelling processes due to (de-)hydration of the clay-stone. Previous investigations yielded the principal applicability of a viscous constitutive model on clay-stone and the principal transferability of this kind of physical model from salt rock to clay-stone whilst taking into account additional characteristics typical for clay-stone, such as the anisotropy of the primary stress state, the transverse isotropy of the stress-strain relationship regarding the orientation of inherent bedding planes, the presence of a latent but mechanically effective discontinuity fabric, or effects from hydraulic processes (e.g. desaturation, see above). Current research work incorporating own laboratory investigations and deformation measurement data acquired in underground openings at the Tournemire site has led to some success in developing a viscous physical model allowing for the aforementioned characteristics for a two-dimensional numerical simulation of this very well documented case study. This model was employed in a next step for a three-dimensional numerical simulation of a drift excavation in the framework of an actually conducted mine-by test. In this test, rock mass deformations in various places at different distances from the drift were recorded by extensometer measurements during the excavation process. An obtained simulation result with the measurement data published by Rejeb et al. (2007) for the extensometer closest to the drift is shown. The order of magnitude of the calculated values is within the order of magnitude of the recorded data, and although a discrepancy in magnitude is still remaining, a trend correspondence between the simulated and the measured deformations

  8. Modelling of the mechanical behaviour and damage of clay-stones: application to the East argillite

    International Nuclear Information System (INIS)

    Aublive-Conil, N.

    2003-03-01

    The storage in deep geological formation is one of the solutions retained by France for the management of highly long life radioactive waste. The retained host rock is a clay-stone named East argillite located in the departments of Meuse and Haute-Marne. A thermodynamic formulation is used to propose a rheological model, which reproduces the mechanical behavior of clay-stones. Initially, an anisotropic damage plastic model was formulated in order to describe material degradations. Then, the damage plastic model is reformulated in order to taken into account the damage influence on the hydraulic behavior of porous material. The numerical simulations correctly reproduce the mechanical behavior of East Argillites but also the anisotropy of the hydraulic behavior introduced by the damage effect. (author)

  9. Ability of One-Dimensional Hairsine-Rose Erosion Model to Predict Sediment Transport over a Soil with Significant Surface Stones

    Science.gov (United States)

    Jomaa, S.; Barry, D. A.; Sander, G. C.; Parlange, J.-Y.; Heng, B. C. P.; Tromp-van Meerveld, H. J.

    2010-05-01

    Surface stones affect erosion rates by reducing raindrop-driven detachment and protecting the original soil against overland flow induced-hydraulic stress. Numerous studies have shown that the effect of surface stones on erosion depends on both the stone characteristics (e.g., size, distribution) and the soil properties. The aim of this study was (i) to quantify how the stone characteristics can affect the total sediment concentration and the concentrations of the individual size classes, (ii) to test if stones affect preferentially a particular size class within the eroded sediment and (iii) to determine whether the 1D Hairsine-Rose (H-R) erosion model can represent the experimental data. A series of laboratory experiments were conducted using the 2 m × 6 m EPFL erosion flume for a high rainfall intensity (60 mm/h) event on a gentle slope (2.2%). The flume was divided into two identical 1-m wide flumes. This separation was done to allow simultaneous replicate experiments. Experiments were conducted with different configurations and scenarios (stone coverage, size and emplacement). Three coverage proportions (20%, 40%, and 70%), two stone diameters (3-4 and 6-7 cm) and two emplacement types (topsoil and partially embedded) were tested. For each experiment, the total sediment concentration, the concentration for the individual size classes, and the flume discharge were measured. Infiltration rates were measured at different depths and locations. A high resolution laser scanner provided details of the surface change due to erosion during the experiments. This technique allowed us to quantify the spatial distribution of eroded soil and to understand better if sediment transport is 1D or rather 2D over the flumes. The one-dimensional Hairsine-Rose (H-R) erosion model was used to fit the integrated data and to provide estimates of the parameters. The ability of the 1D H-R model to predict the measured sediment concentrations in the presence of stones in the soil matrix

  10. A data mining based model for selecting type of treatment for kidney stone patients

    Directory of Open Access Journals (Sweden)

    Sepehri MM

    2009-09-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Data mining as a multidisciplinary field is rooted in the fields such as statistics, mathematics, computer science and artificial intelligence and has been gaining momentum in scientific, managerial, and executive applications in health care. Data mining can be defined as the automated extraction of valuable, practical and hidden knowledge and information from large data. Applying data mining in medical records and data is of utmost importance for health care givers and providers and brings vital and valuable outcomes. Data mining can help doctors come up with better recommendations and plans for treatment which actually in many respects have significant impact on patients' life and satisfaction In this paper we have proposed and utilized data mining methods to extract hidden information in medical records of pelvis stone patients with ureteral stone. We have tried to design a decision support system model to be applicable for selecting type of treatment for these groups of patients."n"nMethods: We gathered needed information from Shahid Hashemi Nejad hospital. In this research we have used decision tree as a data mining tool, for selecting suitable treatment for patients with ureteral stone. This

  11. Purbeck Stone - A possible Global Heritage Stone from England

    Science.gov (United States)

    Marker, Brian

    2014-05-01

    By definition, a Global Heritage Stone Resource (GHSR) should have international significance. The Purbeck Group of uppermost Jurassic to lowermost Cretaceous age (Tithonian- Berriasian) outcrops mainly in the Purbeck area of Dorset, England. It was deposited in shallow freshwater to brackish lagoons with occasional marine incursions. Limestones, mainly biosparites, occur at 6 main levels. Differences in bed thickness, jointing and hardness make it suitable for a variety of purposes including dimension stone, monumental and ornamental stone, roofing tiles, paving, flooring and rockery stone. Near the top of the sequence is a dark gastropod biosparite, traditionally called Purbeck Marble, easily carved, which has been extensively used for decorative interior work in churches and cathedrals particularly for fonts, tombs, flooring and facings on columns for example in the medieval cathedrals of Salisbury, Exeter, Durham, York and Wells and Worcester and Westminster Abbey. The stone was extracted at least from Roman times (1st century AD) through the medieval period. Quarrying expanded from about 1700 reaching a peak in the late 18th and 19th centuries. Stone was transported first by sea but later by rail for wider use. Used in many local buildings, it gives an important element of local character. Many of the villages are designated conservation areas with a requirement for repair, maintenance and new building using local stone. Initially the stone was taken from quarries but was later mined. The number of operating companies declined from 15 to 5 over the past 40 years, with 10 active small quarries. Outputs are from few hundred tonnes to a few thousand tonnes per annum or about 9 to 12 years of permitted reserves but the Planning Authority intends to make sufficient provision for production at recent levels for their development plan period. The extraction sites are in an Area of Outstanding Natural Beauty and close to Jurassic Coast World Heritage Site. This might

  12. Kidney Stones (For Parents)

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Kidney Stones KidsHealth / For Parents / Kidney Stones What's in ... other treatments to help remove the stones. How Kidney Stones Form It's the kidneys' job to remove ...

  13. Shielding features of quarry stone

    International Nuclear Information System (INIS)

    Hernandez V, C.; Contreras S, H.; Hernandez A, L.; Baltazar R, A.; Escareno J, E.; Mares E, C. A.; Vega C, H. R.

    2010-10-01

    Quarry stone lineal attenuation coefficient for gamma-rays has been obtained. In Zacatecas, quarry stone is widely utilized as a decorative item in buildings, however its shielding features against gamma-rays unknown. The aim of this work is to determine the shielding properties of quarry stone against γ-rays using Monte Carlo calculations where a detailed model of a good geometry experimental setup was carried out. In the calculations 10 pieces 10 X 10 cm 2 of different thickness were utilized to evaluate the photons transmission as the quarry stone thickness is increased. It was noticed that transmitted photons decay away as the shield thickness is increased, these results were fitted to an exponential function were the linear attenuation coefficient was estimated. Also, using XCOM code the linear attenuation coefficient from several keV up to 100 MeV was estimated. From the comparison between Monte Carlo results and XCOM calculations a good agreement was found. For 0.662 MeV γ-rays the attenuation coefficient of quarry stone, whose density is 2.413 g-cm -3 , is 0.1798 cm -1 , this mean a X 1/2 = 3.9 cm, X 1/4 = 7.7 cm, X 1/10 = 12.8 cm, and X 1/100 = 25.6 cm. Having the information of quarry stone performance as shielding give the chance to use this material to shield X and γ-ray facilities. (Author)

  14. Comparison of reconstructed rapid prototyping models produced by 3-dimensional printing and conventional stone models with different degrees of crowding.

    Science.gov (United States)

    Wan Hassan, Wan Nurazreena; Yusoff, Yusnilawati; Mardi, Noor Azizi

    2017-01-01

    Rapid prototyping models can be reconstructed from stereolithographic digital study model data to produce hard-copy casts. In this study, we aimed to compare agreement and accuracy of measurements made with rapid prototyping and stone models for different degrees of crowding. The Z Printer 450 (3D Systems, Rock Hill, SC) reprinted 10 sets of models for each category of crowding (mild, moderate, and severe) scanned using a structured-light scanner (Maestro 3D, AGE Solutions, Pisa, Italy). Stone and RP models were measured using digital calipers for tooth sizes in the mesiodistal, buccolingual, and crown height planes and for arch dimension measurements. Bland-Altman and paired t test analyses were used to assess agreement and accuracy. Clinical significance was set at ±0.50 mm. Bland-Altman analysis showed the mean bias of measurements between the models to be within ±0.15 mm (SD, ±0.40 mm), but the 95% limits of agreement exceeded the cutoff point of ±0.50 mm (lower range, -0.81 to -0.41 mm; upper range, 0.34 to 0.76 mm). Paired t tests showed statistically significant differences for all planes in all categories of crowding except for crown height in the moderate crowding group and arch dimensions in the mild and moderate crowding groups. The rapid prototyping models were not clinically comparable with conventional stone models regardless of the degree of crowding. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  15. Calcium oxalate stone and gout.

    Science.gov (United States)

    Marickar, Y M Fazil

    2009-12-01

    Gout is well known to be produced by increased uric acid level in blood. The objective of this paper is to assess the relationship between gout and calcium oxalate stone formation in the humans. 48 patients with combination of gout and calcium oxalate stone problem were included. The biochemical values of this group were compared with 38 randomly selected uric acid stone patients with gout, 43 stone patients with gout alone, 100 calcium oxalate stone patients without gout and 30 controls, making a total of 259 patients. Various biochemical parameters, namely serum calcium, phosphorus and uric acid and 24-h urine calcium, phosphorus, uric acid, oxalate, citrate and magnesium were analysed. ANOVA and Duncan's multiple-range tests were performed to assess statistical significance of the variations. The promoters of stone formation, namely serum calcium (P stone patients and gouty calcium oxalate stone patients compared to the non-gouty patients and controls. Urine oxalate (P stones patients. The inhibitor urine citrate (P stone gouty patients, followed by the gouty uric acid stone formers and gouty calcium oxalate stone patients. The high values of promoters, namely uric acid and calcium in the gouty stone patients indicate the tendency for urinary stone formation in the gouty stone patients. There is probably a correlation between gout and calcium oxalate urinary stone. We presume this mechanism is achieved through the uric acid metabolism. The findings point to the summation effect of metabolic changes in development of stone disease.

  16. Acute management of stones

    DEFF Research Database (Denmark)

    Jung, Helene; Osther, Palle J S

    2015-01-01

    INTRODUCTION: Stone management is often conservative due to a high spontaneous stone passage rate or non-symptomatic calyceal stones that do not necessarily require active treatment. However, stone disease may cause symptoms and complications requiring urgent intervention. MATERIAL AND METHODS: I...... with careful consideration of stone size and location, symptoms, patient comorbidity and radiation dose. CONCLUSION: In case of infective hydronephrosis, compromised renal function or persistent pain despite adequate analgesic treatment acute intervention is indicated....

  17. Treatment of gallbladder stone with common bile duct stones in the laparoscopic era

    OpenAIRE

    Zhang, Wei-jie; Xu, Gui-fang; Huang, Qin; Luo, Kun-lun; Dong, Zhi-tao; Li, Jie-ming; Wu, Guo-zhong; Guan, Wen-xian

    2015-01-01

    Background: Laparoscopic common bile duct exploration (LCBDE) for stone can be carried out by either laparoscopic transcystic stone extraction (LTSE) or laparoscopic choledochotomy (LC). It remains unknown as to which approach is optimal for management of gallbladder stone with common bile duct stones (CBDS) in Chinese patients. Methods: From May 2000 to February 2009, we prospective treated 346 consecutive patients with gallbladder stones and CBDS with laparoscopic cholecystectomy and LCBDE....

  18. Metabolic Characteristics and Risks Associated with Stone Recurrence in Korean Young Adult Stone Patients.

    Science.gov (United States)

    Kang, Ho Won; Seo, Sung Pil; Kim, Won Tae; Kim, Yong-June; Yun, Seok-Joong; Kim, Wun-Jae; Lee, Sang-Cheol

    2017-08-01

    The aim of this study was to assess the metabolic characteristics and risks of stone recurrence in young adult stone patients in Korea. The medical records of 1532 patients presenting with renal or ureteric stones at our stone clinic between 1994 and 2015 were retrospectively reviewed. Patients were grouped according to age (young adult, 18-29 years; intermediate onset, 30-59 years; old age, ≥60 years) at first presentation, and measurements of clinicometabolic characteristics and risks of stone recurrence were compared. Overall, excretion of urinary stone-forming substances was highest in the intermediate onset group, followed by the young adult and old age groups. Importantly, excretion of urinary citrate was lowest in the young adult group. Kaplan-Meier analyses identified a significant difference between the three age groups in terms of stone recurrence (log rank test, p adult stone patients. Younger age (18-29 years) at first stone presentation was a significant risk factor for stone recurrence, and urinary citrate excretion was an independent risk factor affecting recurrence in this group. Metabolic evaluation and potassium citrate therapy should be considered for young adult stone patients to prevent recurrence.

  19. The relationship between serum and urinary Fetuin-A levels and kidney stone formation among kidney stone patients.

    Science.gov (United States)

    Mehrsai, Abdolrasoul; Guitynavard, Fateme; Nikoobakht, Mohammad Reza; Gooran, Shahram; Ahmadi, Ayat

    2017-01-01

    Mineralization inhibitors are required to prevent the precipitation of minerals and inhibit the formation of kidney stones and other ectopic calcifications. In laboratory studies, Fetuin-A as a glycoprotein has inhibited hydroxyapatite precipitation in calcium and phosphate supersaturated solutions; however, information about patients with kidney stones is limited. The aim of this study was to investigate the association of serum and urinary Fetuin-A levels with calcium oxalate kidney stones. In this case-control study, 30 patients with kidney stones and 30 healthy individuals without any history of urolithiasis who were referred to the urology ward of Sina Hospital of Tehran, Iran, in 2015 were entered into the study. All patients underwent computerized tomography scans. After collecting demographic information, serum and urine levels of Fetuin-A and some other calcification inhibitors and promoters, were measured and compared using T-test, Mann-Whitney and logistic regression between the two study groups. Patients with kidney stones, on average, had lower levels of Serum Fetuin-A (1522.27 ±755.39 vs. 1914.64 ±733.76 μg/ml; P = 0.046) as well as lower levels of Urine Fetuin-A (944.62 ±188.5 vs. 1409.68 ±295.26 μg/ml; P <0.001). Multivariate logistic analysis showed that urinary calcium and serum creatinine are the risk factors and Fetuin-A is a urinary protective factor for kidney stones. PFC Our study showed that patients with kidney stones had lower serum and urinary levels of Fetuin-A. In the logistic regression model, urinary Fetuin-A was reported as a protective factor for kidney stones.

  20. Percutaneous suprapubic stone extraction for posterior urethral stones in children: efficacy and safety.

    Science.gov (United States)

    Safwat, Ahmed S; Hameed, Diaa A; Elgammal, Mohamed A; Abdelsalam, Yasser M; Abolyosr, Ahmad

    2013-08-01

    To evaluate the safety and efficacy of percutaneous suprapubic stone extraction (PSPSE) for pediatric posterior urethral stones. Between July 2007 and June 2010, 54 boys presenting with acute urinary retention due to posterior urethral stones underwent PSPSE. Patients were a mean age of 66.4 months (range, 8-180 months). The stone size was 0.7-1.9 cm. Patients were placed under general anesthesia, and a 7F urethroscope was used to pushback the stone to the bladder. A 3-mm suprapubic puncture with a scalpel was performed, followed by insertion of a straight narrow hemostat through the puncture aided with cystoscopic guidance. The stone was grasped with the hemostat in its narrowest diameter and was extracted percutaneously or crushed if friable. The suprapubic puncture was closed with a single 4-0 Vicryl (Ethicon) suture. Intact stone retrieval was achieved in 45 patients, and the stone was crushed into minute fragments in 9 patients. Intraperitoneal extravasation developed in 1 patient that required open surgical intervention. Mean operative time was 22 minutes. Patients were monitored for up to 17 months, with complete resolution of symptoms and stone clearance. PSPSE provides a minimally invasive approach for the extraction of urethral and bladder stones in the pediatric population. The use of a straight hemostat for suprapubic stone extraction or crushing is a good alternative to suprapubic tract dilation, with minimal morbidity. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Stone composition and metabolic status.

    Science.gov (United States)

    Bibilash, B S; Vijay, Adarsh; Fazil Marickar, Y M

    2010-06-01

    This paper aims to study the correlation between biochemical risk factors of the stone former and the type of oxalate stone formed, namely calcium oxalate monohydrate (COM) and calcium oxalate dehydrate (COD). A retrospective study of 487 patients who had been attending the urinary stone clinic, Trivandrum during 1998-2007 was conducted. The stones retrieved from them were subjected to chemical analysis and FTIR spectrographic analysis. They were categorized into COM, COD, mixed COM+COD and others. Of 142 pure calcium oxalate stone patients, 87 were predominantly COM stone formers and 55 COD stone formers. Their metabolic status of 24 h urine and serum was assessed. The values of urine calcium, phosphorus, uric acid, magnesium, creatinine, oxalate, citric acid, sodium and potassium, serum values of calcium, phosphorus, uric acid, magnesium and creatinine and calculated values of creatinine clearance, tubular reabsorption of phosphate, calcium magnesium ratio and calcium oxalate ratio were recorded. Comparison was made between the COM stone group and the COD stone group. Patients forming COM stones had significantly higher mean values for urine calcium (P stone forming patients. All other values failed to show significant difference. Patients, with higher urine oxalate, formed COM stones. Those with low magnesium (which is an inhibitor) formed more of COD stones. Urine calcium was high in both groups without showing significant variation from the mean. In patients with high calcium-oxalate and calcium-magnesium ratios, there is higher chance of forming a COD stone than COM. Identification of the crystallization pattern of the calcium stone will help in selecting treatment modalities.

  2. IGCP 637 Heritage Stone Designation: A UNESCO and IUGS project on natural stones

    Science.gov (United States)

    Pereira, Dolores; Cooper, Barry; Schouenborg, Björn; Marker, Brian; Kramar, Sabina

    2017-04-01

    IGCP 637 was approved in 2015 to facilitate establishment of a new international geological standard for building and ornamental stones. Formal international recognition of those natural stone types that have achieved widespread utilization in human culture is now underway and the term "Global Heritage Stone Resource" (GHSR) has been proposed for this designation. Stones that have been used in heritage construction, sculptural masterpieces, as well as in utilitarian (yet culturally important) applications are obvious GHSR candidates. In co-ordination with these aims the project has an associated role to promote the adoption and use of the GHSR designation. Consequently an interim list of potential GHSRs is maintained and a register of GHSR approved stones is being created. IGCP 637 also enhances the capacity of the International Union of Geological Sciences (IUGS) in the realm of dimension stone and geological standards as it is the first IUGS involvement in this subject. As a consequence, the largest known international grouping of dimension stone professionals has been established. Within IGCP 637 a web page has been created at www.globalheritagestone.com, including information on the Working Group and also specific information on the evolution of the project. Several researchers were funded to attend the Heritage Stone working group activities, including researchers from Algeria, Malawi, India, Italy and Russia. We also have produced many publications, both as individual papers and special issues in journals included in the Journal Citation Reports. Monographs are being prepared at present. Hopefully, IGCP 637 will help to widen the circle of researchers interested in natural stones as part of our geoheritage. Heritage Stone references: articles and special issues - Pereira, D. and Marker, B. (2016) The value of original natural stone in the context of architectural heritage. Geosciences, 6, 13. - Heritage Stone 1. Ed. Pereira and Pratt. (2016). Geoscience

  3. Papillary Ductal Plugging is a Mechanism for Early Stone Retention in Brushite Stone Disease

    DEFF Research Database (Denmark)

    Williams, James C; Borofsky, Michael S; Bledsoe, Sharon B

    2018-01-01

    PURPOSE: Mechanisms of early stone retention in the kidney are under studied and poorly understood. To date attachment via Randall's plaque is the only widely accepted theory in this regard, which is best described in idiopathic calcium oxalate stone formers. Brushite stone formers are known...... to have distinct papillary morphology relative to calcium oxalate stone formers. As such we sought to determine whether stone attachment mechanisms in such patients may be similarly unique. MATERIALS AND METHODS: Patients undergoing percutaneous and or ureteroscopic procedures for stone removal consented...... to endoscopic renal papillary examination and individual stone collection. Each removed stone was processed using micro computerized tomography to assess the 3-dimensional microstructure and the minerals contained, and search for common structural features indicative of novel mechanisms of early growth...

  4. Shock Wave Lithotripsy in Ureteral Stones: Evaluation of Patient and Stone Related Predictive Factors

    Directory of Open Access Journals (Sweden)

    Ozgur Yazici

    2015-08-01

    Full Text Available ABSTRACTPurpose:To evaluate the patient and stone related factors which may influence the final outcome of SWL in the management of ureteral stones.Materials and Methods:Between October 2011 and October 2013, a total of 204 adult patients undergoing SWL for single ureteral stone sizing 5 to 15 mm were included into the study program. The impact of both patient (age, sex, BMI, and stone related factors (laterality, location, longest diameter and density as CT HU along with BUN and lastly SSD (skin to stone distance on fragmentation were analysed by univariate and multivariate analyses. Results: Stone free rates for proximal and distal ureteral stones were 68.8% and 72.7%, respectively with no statistically significant difference between two groups (p=0.7. According to univariate and multivariate analyses, while higher BMI (mean: 26.8 and 28.1, p=0.048 and stone density values (mean: 702 HU and 930 HU, p<0.0001 were detected as statistically significant independent predictors of treatment failure for proximal ureteral stones, the only statistically significant predicting parameter for the success rates of SWL in distal ureteral stones was the higher SSD value (median: 114 and 90, p=0.012.Conclusions:Our findings have clearly shown that while higher BMI and increased stone attenuation values detected by NCCT were significant factors influencing the final outcome of SWL treatment in proximal ureteral stones; opposite to the literature, high SSD was the only independent predictor of success for the SWL treatment of distal ureteral stones.

  5. Experimental study of thermo-hydro-mechanical behaviour of Callovo-Oxfordian Clay-stone

    International Nuclear Information System (INIS)

    Mohajerani, M.

    2011-01-01

    During the different phases of the exothermic radioactive waste deep disposal (excavation, operation) and after permanent closure, the host rock is submitted to various coupled mechanical, hydraulic and thermal phenomena. Hence, a thorough investigation of the thermo-hydro-mechanical behaviour of the rock is necessary to complete existing data and to better understand and model the short and long term behaviour of the Callovo-Oxfordian (COx) clay formation in Bure (Meuse/Haute-Marne - M/HM), considered by ANDRA as a potential host rock in France.In this work, the compression - swelling behaviour of the COx Clay-stone was first investigated by carrying out a series of high-pressure oedometric tests. The results, interpreted in terms of coupling between damage and swelling, showed that the magnitude of swelling was linked to the density of the fissures created during compression. In a second step, the hydro-mechanical and thermo-hydro-mechanical behaviour of the saturated Clay-stone under a mean stress close to the in situ one were investigated by using two devices with short drainage path (10 mm), namely a isotropic cell and a newly designed hollow cylinder triaxial cell with local displacement measurements. These devices helped to solve two majors problems related to testing very low permeability materials: i) a satisfactory previous sample saturation (indicated by good Skempton values) and ii) satisfactory drainage conditions. Some typical constitutive parameters (Skempton and Biot's coefficients, drained and undrained compressibility coefficients) have been determined at ambient temperature through isotropic compression tests that also confirmed the transverse isotropy of the Clay-stone. The consistency of the obtained parameters has been checked in a saturated poro-elastic framework. Two aspects of the thermo-hydro-mechanical behaviour of the COx Clay-stone have then been investigated through different heating tests and through drained and undrained isotropic

  6. Retrograde intrarenal stone surgery for extracorporeal shock-wave lithotripsy-resistant kidney stones

    DEFF Research Database (Denmark)

    Jung, Helene; Nørby, Bettina; Osther, Palle Jörn

    2006-01-01

    OBJECTIVE: The newer flexible ureteroscopes, 150-200-microm holmium YAG laser fibres and superflexible Dormia baskets have made it possible to reach and treat stones in all parts of the kidney. The object of this evaluation was to study the outcome of retrograde intrarenal stone surgery (RIRS......) for extracorporeal shock-wave lithotripsy (ESWL)-resistant kidney stones. MATERIAL AND METHODS: A total of 38 consecutive patients (18 males, 20 females) participated in the study. All patients had undergone ESWL prior to RIRS without success. In all cases the stones could be reached with the endoscope. Calculi...... ranged in size from 3 to 20 mm (mean 9 mm). In 32 cases the stones were fragmented using a holmium YAG laser and in six the stones could be extracted using zero-tip Dormia baskets without fragmentation. Sixteen patients had lower calyceal calculi and eight had an abnormal anatomy of the upper urinary...

  7. Factors affecting stone-free rate and complications of percutaneous nephrolithotomy for treatment of staghorn stone.

    Science.gov (United States)

    el-Nahas, Ahmed R; Eraky, Ibrahim; Shokeir, Ahmed A; Shoma, Ahmed M; el-Assmy, Ahmed M; el-Tabey, Nasr A; Soliman, Shady; Elshal, Ahmed M; el-Kappany, Hamdy A; el-Kenawy, Mahmoud R

    2012-06-01

    To determine factors affecting the stone-free rate and complications of percutaneous nephrolithotomy (PNL) for treatment of staghorn stones. The computerized database of patients who underwent PNL for treatment of staghorn stones between January 2003 and January 2011 was reviewed. All perioperative complications were recorded and classified according to modified Clavien classification system. The stone-free rate was evaluated with low-dose noncontrast computed tomography (CT). Univariate and multivariate statistical analyses were performed to determine factors affecting stone-free and complication rates. The study included 241 patients (125 male and 116 female) with a mean age of 48.7 ±14.3 years. All patients underwent 251 PNL (10 patients had bilateral stones). The stone-free rate of PNL monotherapy was 56% (142 procedures). At 3 months, the stone-free rate increased to 73% (183 kidneys) after shock wave lithotripsy. Independent risk factors for residual stones were complete staghorn stone and presence of secondary calyceal stones (relative risks were 2.2 and 3.1, respectively). The complication rate was 27% (68 PNL). Independent risk factors for development of complications were performance of the procedure by urologists other than experienced endourologist and positive preoperative urine culture (relative risks were 2.2 and 2.1, respectively). Factors affecting the incidence of residual stones after PNL are complete staghorn stones and the presence of secondary calyceal stones. Complications are significantly high if PNL is not performed by an experienced endourologist or if preoperative urine culture is positive. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. Kidney stones - self-care

    Science.gov (United States)

    ... self-care; Nephrolithiasis and self-care; Stones and kidney - self-care; Calcium stones and self-care; Oxalate ... provider or the hospital because you have a kidney stone. You will need to take self-care ...

  9. A review of the mathematical models used for simulation of calcareous stone deterioration in historical buildings

    Science.gov (United States)

    Saba, M.; Quiñones-Bolaños, E. E.; Barbosa López, Aida Liliana

    2018-05-01

    Historic buildings and monuments are often composed of carbonate-based stone materials, susceptible to deterioration by the action of acidic substances on its main component, calcite (CaCO3). Today the levels of air pollution that attack heterogeneous structures with a mixture of different materials, usually of complex and articulated geometries, are the main responsible of the damage of calcareous stones. However the mechanisms of degradation of the stone and the factors that affect them cannot be simply specified, due to the sum coupled processes involving physical, chemical and biological changes, associated with capillarity and porosity, on the other hand the management of large number of samples and the cost of characterization analysis, modeling can contemplate a tool for the care and protection of real estate over time. Reason why this work shows a bibliographical review of the mathematical models that aim to describe how the deterioration of the surfaces of these structures varies over time, with particular attention to surface recession of stone, as a function of sets of variables that have been considered determinants in the different cases studied. It has been shown that in the last 30 years the models has had a revealing evolution due to the fact that the phenomenon has been gradually understood, putting in the background variables such as SO2 because of its reduction worldwide, and introducing variables such as HNO3 which has had, on the contrary, increasing values. In addition, it has been shown that linear polynomials, even if they lend themselves well to represent the phenomenon, in the last 10 years have been replaced by equations or systems of differential equations with one or more variables taken into account. Finally, it was revealed the lack of an inclusive model, capable of including all possible deterioration processes, and that time by time can be adapted to different case studies, in different parts of the world and with different

  10. Lessons from a Stone Farm

    Science.gov (United States)

    Kavanagh, John P.; Rao, P. Nagaraj

    2007-04-01

    The stone farm is a system for measuring macroscopic stone growth of 12 calcium stones simultaneously. It is based on mixed suspension, mixed product removal continuous crystallization principles and the stones are grown continuously for about 500 hours or more. The growth of the stones follows a surface area dependent pattern and the growth rate constants are very similar irrespective of whether the stating materials are fragments of human stone or pieces of marble chip. Increasing citrate from 2mM to 6mM caused a significant growth inhibition which persisted in the presence of urinary macromolecules. Phytate was a very effective inhibitor (about 50% at sub-μM concentrations) but the effective concentration was increased by an order of magnitude in the presence of urinary macromolecules. The effective concentration for inhibition in a crystallization assay was a further two orders of magnitude higher. Urinary macromolecules or almost whole urine were also strongly inhibitory although neither human serum albumin nor bovine mucin had any great effect. The relationship between the size distribution of crystals in suspension and the stone enlargement rate suggests that the primary enlargement mechanism for these in vitro stones is through aggregation. The stone farm is a powerful tool with which to study crystallization inhibitors in a new light. Some differences between inhibition of crystallization and inhibition of stone growth have emerged and we have obtained quantitative evidence on the mechanism of stone enlargement in vitro. Our findings suggest that the interface between crystals in suspension and the stone surface is the key to controlling stone enlargement.

  11. The effect of disinfection of alginate impressions with 35% beetle juice spray on stone model linear dimensional changes

    Directory of Open Access Journals (Sweden)

    Anggra Yudha Ramadianto

    2007-07-01

    Full Text Available Dimensional stability of alginate impression is very important for treatment in dentistry. This study was to find the effect of the beetle juice spray procedure on alginate impression on gypsum model linear dimensional changes. This experimental study used 25 samples, divided into 5 groups. The first group, as control, were the alginate impressions filled with dental stone immediately after forming. The other four groups were the alginate impressions gel spray each 1,2,3, and 4 times with 35% beetle juice and then filled with dental stone. Dimensional changes were measured in the lower part of the plaster model from buccal-lingual and mesial-distal direction and also measured in the outer distance between the upper part of the stone model by using Mitutoyo digital micrometre and profile projector scaled 0,001 mm. The results of mesial-distal diameter average of the control group and group 2,3,4, and 5 were 9.909 mm, 9.852 mm, 9.845 mm, 9.824 mm, and 9.754 mm. Meanwhile, the results of buccal-lingual diameter average were 9.847 mm, 9.841 mm, 9.826 mm, 9.776 mm, and 9.729 mm. The results of the outer distance between the upper part of the stone model were 31.739 mm, 31.689 mm, 31.682 mm, 31.670 mm, and 31.670 mm. The data of this study was evaluated statistically based on the variant analysis. The conclusion of this study was statistically, there was no significant effect on gypsum model linear dimensional changes obtained from alginate impressions sprayed with 35% beetle juice.

  12. A neural network - based algorithm for predicting stone - free status after ESWL therapy.

    Science.gov (United States)

    Seckiner, Ilker; Seckiner, Serap; Sen, Haluk; Bayrak, Omer; Dogan, Kazim; Erturhan, Sakip

    2017-01-01

    The prototype artificial neural network (ANN) model was developed using data from patients with renal stone, in order to predict stone-free status and to help in planning treatment with Extracorporeal Shock Wave Lithotripsy (ESWL) for kidney stones. Data were collected from the 203 patients including gender, single or multiple nature of the stone, location of the stone, infundibulopelvic angle primary or secondary nature of the stone, status of hydronephrosis, stone size after ESWL, age, size, skin to stone distance, stone density and creatinine, for eleven variables. Regression analysis and the ANN method were applied to predict treatment success using the same series of data. Subsequently, patients were divided into three groups by neural network software, in order to implement the ANN: training group (n=139), validation group (n=32), and the test group (n=32). ANN analysis demonstrated that the prediction accuracy of the stone-free rate was 99.25% in the training group, 85.48% in the validation group, and 88.70% in the test group. Successful results were obtained to predict the stone-free rate, with the help of the ANN model designed by using a series of data collected from real patients in whom ESWL was implemented to help in planning treatment for kidney stones. Copyright® by the International Brazilian Journal of Urology.

  13. The integrated modeling system STONE for calculating nutrient emissions from agriculture in the Netherlands

    NARCIS (Netherlands)

    Wolf, J.; Beusen, A.H.W.; Groenendijk, P.; Kroon, T.; Rötter, R.P.; Zeijts, van H.

    2003-01-01

    For the Netherlands, a nutrient emission modeling system, called STONE, has been developed. It was designed for evaluation at the national and regional scale of the effects of changes in the agricultural sector (e.g. changes in fertilizer recommendations and cropping patterns) and in policy measures

  14. Celtic Stone Dynamics Revisited Using Dry Friction and Rolling Resistance

    Directory of Open Access Journals (Sweden)

    J. Awrejcewicz

    2012-01-01

    Full Text Available The integral model of dry friction components is built with assumption of classical Coulomb friction law and with specially developed model of normal stress distribution coupled with rolling resistance for elliptic contact shape. In order to avoid a necessity of numerical integration over the contact area at each the numerical simulation step, few versions of approximate model are developed and then tested numerically. In the numerical experiments the simulation results of the Celtic stone with the friction forces modelled by the use of approximants of different complexity (from no coupling between friction force and torque to the second order Padé approximation are compared to results obtained from model with friction approximated in the form of piecewise polynomial functions (based on the Taylor series with hertzian stress distribution. The coefficients of the corresponding approximate models are found by the use of optimization methods, like as in identification process using the real experiment data.

  15. Canada's National Building Stone: Tyndall Stone from Manitoba

    Science.gov (United States)

    Pratt, Brian R.; Young, Graham A.; Dobrzanski, Edward P.

    2016-04-01

    Tyndall Stone is a distinctively mottled and highly fossiliferous dolomitic limestone that belongs to the Selkirk Member of the Red River Formation, of Late Ordovician (Katian) age. It has been quarried at Garson, Manitoba, 37 km northeast of Winnipeg, since 1895, although other quarries in the area go back to 1832. Tyndall Stone, so named because it was shipped by rail from nearby Tyndall, is currently produced by Gillis Quarries Limited. It has various uses as a dimension stone. Large slabs, most often cut parallel to bedding, face the exterior or interior of many important buildings such as the Parliament Buildings and the Canadian Museum of Civilization in the Ottawa area, the Empress Hotel in Victoria, and the provincial legislatures in Winnipeg and Regina, as well as many commercial buildings especially in the Canadian prairies. At the quarries, the stone is cut vertically, using eight foot (2.44 m) diameter saws mounted on one hundred foot (30.5 m) tracks, then split into 6-8 tonne blocks that are moved using front-end loaders. Gillis Quarries operates a large finishing plant with an area of about 4000 m2. Stone is processed along advanced cutting lines that feature eight primary saws and six gantry saw stations, allowing it to be made into a variety of sizes, shapes, and finishes. The Selkirk Member is 43 m thick and the stone is extracted from a 6-8 m thick interval within the lower part. The upper beds tend to be more buff-coloured than the grey lower beds due to weathering by groundwater. The stone is massive, but extracted blocks are less than ~1m thick due to splitting along stylolites. Consisting of bioturbated wackestone to packstone, the Tyndall Stone was deposited in a shallow-marine environment within the photic zone, in the central part of the vast equatorial epicontinental sea that covered much of Laurentia. Scattered thin, bioclastic grainstone lenses record brief, low-energy storm events. The distinctive mottles are formed by dolomitized

  16. Kidney stone erosion by micro scale hydrodynamic cavitation and consequent kidney stone treatment.

    Science.gov (United States)

    Perk, Osman Yavuz; Şeşen, Muhsincan; Gozuacik, Devrim; Koşar, Ali

    2012-09-01

    The objective of this study is to reveal the potential of micro scale hydrodynamic bubbly cavitation for the use of kidney stone treatment. Hydrodynamically generated cavitating bubbles were targeted to the surfaces of 18 kidney stone samples made of calcium oxalate, and their destructive effects were exploited in order to remove kidney stones in in vitro experiments. Phosphate buffered saline (PBS) solution was used as the working fluid under bubbly cavitating conditions in a 0.75 cm long micro probe of 147 μm inner diameter at 9790 kPa pressure. The surface of calcium oxalate type kidney stones were exposed to bubbly cavitation at room temperature for 5 to 30 min. The eroded kidney stones were visually analyzed with a high speed CCD camera and using SEM (scanning electron microscopy) techniques. The experiments showed that at a cavitation number of 0.017, hydrodynamic bubbly cavitation device could successfully erode stones with an erosion rate of 0.31 mg/min. It was also observed that the targeted application of the erosion with micro scale hydrodynamic cavitation may even cause the fracture of the kidney stones within a short time of 30 min. The proposed treatment method has proven to be an efficient instrument for destroying kidney stones.

  17. Effect of Ferrous Additives on Magnesia Stone Hydration

    Science.gov (United States)

    Zimich, V.

    2017-11-01

    The article deals with the modification of the magnesia binder with additives containing two- and three-valent iron cations which could be embedded in the chloromagnesium stone structure and also increase the strength from 60 MPa in a non-additive stone to 80MPa, water resistance from 0.58 for clear stone to 0.8 and reduce the hygroscopicity from 8% in the non-additive stone to 2% in the modified chloromagnesium stone. It is proposed to use the iron hydroxide sol as an additive in the quantities of up to 1% of the weight of the binder. The studies were carried out using the modern analysis methods: the differentialthermal and X-ray phase analysis. The structure was studied with an electron microscope with an X-ray microanalyzer. A two-factor plan-experiment was designed which allowed constructing mathematical models characterizing the influence of variable factors, such as the density of the zatcher and the amount of sol in the binder, on the basic properties of the magnesian stone. The result of the research was the magnesia stone with the claimed properties and formed from minerals characteristic for magnesian materials as well as additionally formed from amachenite and goethite. It has been established that a highly active iron hydroxide sol the ion sizes of which are commensurate with magnesium ions is actively incorporated into the structure of pentahydroxychloride and magnesium hydroxide changing the habit of crystals compacting the structure of the stone and changing its hygroscopicity.

  18. A case report of ureteral cast stone and giant urethral stone, respectively

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Yung; Rhee, Song Joo; Choi, Ki Chul [School of Medicine, Jeongbug National University, Jeonju (Korea, Republic of)

    1980-12-15

    Urinary lithiasis is one of the most common disease of the urinary tract. It occurs more frequently in men than in women but rare in children and in blacks; a familial predisposition is often encountered. Ureteral stones originate in the kidney. Gravity and peristalis contribute to spontaneous passage into and down the ureter. Ureterovesical junction is the most frequent lodging site of stone. In our hospital one case of ureteral cast stone and giant urethral stone were found respectively and they were confirmed by radiological examination and surgery on Aug. 1978 and Jan. 1979. Ureteral cast stone which had been introduced and named first by Kiyonobu Tari and Kikjiro So in 1972 was very giant unusually. It may be the only one till now. Our patient was 36 years old female who has been suffered from intermittent right flank pain for 10 years. On KUB giant cylindrical radiopaque shadow was shown on RLQ extended to right minor pelvis and this was confirmed as a stone by retrograde ureteral catheterization. A stone measured 13cm x 1.5cm was found above the ureterovesical junction during operation. Follow up excretory urogram one year after operation showed no functional improvement of right kidney. Urethral stone is also unusual urinary lithiasis. This 60 years old male patient was been suffered from non-tender palpable hard mass on scrotal area and intermittent urinary retention. When urinary retention was occurred it was relieved by manipulation of the mass by himself. On plain film oval shaped giant radiopaque shadow was shown on cavernous urethral region. On urethrocystogram anterior urethra was opacified, but posterior urethra and bladder were not opacified and multiple fistulous leakage was identified. A stone measured 6.5cm x 3.5cm was found in cavernous urethra during operation.

  19. A case report of ureteral cast stone and giant urethral stone, respectively

    International Nuclear Information System (INIS)

    Song, Ho Yung; Rhee, Song Joo; Choi, Ki Chul

    1980-01-01

    Urinary lithiasis is one of the most common disease of the urinary tract. It occurs more frequently in men than in women but rare in children and in blacks; a familial predisposition is often encountered. Ureteral stones originate in the kidney. Gravity and peristalis contribute to spontaneous passage into and down the ureter. Ureterovesical junction is the most frequent lodging site of stone. In our hospital one case of ureteral cast stone and giant urethral stone were found respectively and they were confirmed by radiological examination and surgery on Aug. 1978 and Jan. 1979. Ureteral cast stone which had been introduced and named first by Kiyonobu Tari and Kikjiro So in 1972 was very giant unusually. It may be the only one till now. Our patient was 36 years old female who has been suffered from intermittent right flank pain for 10 years. On KUB giant cylindrical radiopaque shadow was shown on RLQ extended to right minor pelvis and this was confirmed as a stone by retrograde ureteral catheterization. A stone measured 13cm x 1.5cm was found above the ureterovesical junction during operation. Follow up excretory urogram one year after operation showed no functional improvement of right kidney. Urethral stone is also unusual urinary lithiasis. This 60 years old male patient was been suffered from non-tender palpable hard mass on scrotal area and intermittent urinary retention. When urinary retention was occurred it was relieved by manipulation of the mass by himself. On plain film oval shaped giant radiopaque shadow was shown on cavernous urethral region. On urethrocystogram anterior urethra was opacified, but posterior urethra and bladder were not opacified and multiple fistulous leakage was identified. A stone measured 6.5cm x 3.5cm was found in cavernous urethra during operation

  20. Porous Media and Immersed Boundary Hybrid-Modelling for Simulating Flow in Stone Cover-Layers

    DEFF Research Database (Denmark)

    Jensen, Bjarne; Liu, Xiaofeng; Christensen, Erik Damgaard

    In this paper we present a new numerical modelling approach for coastal and marine applications where a porous media conceptual model was combined with a free surface volume-of-fluid (VOF) model and an immersed boundary method (IBM). The immersed boundary model covers the method of describing....... In this paper, the model is applied to investigate two practical cases in terms of a cover layer of stones on a flat bed under oscillatory flow at different packing densities, and a rock toe structure at a breakwater....

  1. Introduction. Leave no stone unturned: Perspectives on ground stone artefact research

    OpenAIRE

    Danny Rosenberg; Yorke Rowan; Tatjana Gluhak

    2016-01-01

    Ground stone tools served in many physical and social contexts through millennia, reflecting a wide variety of functions. Although ground stone tool studies were neglected for much of early archaeology, the last few decades witnessed a notable international uptick in the way archaeologists confront this multifaceted topic. Today, with the advance of archaeology as a discipline, research into ground stone artefacts is moving into a new phase that integrates high resolution documentation with n...

  2. Treatment of gallbladder stone with common bile duct stones in the laparoscopic era.

    Science.gov (United States)

    Zhang, Wei-jie; Xu, Gui-fang; Huang, Qin; Luo, Kun-lun; Dong, Zhi-tao; Li, Jie-ming; Wu, Guo-zhong; Guan, Wen-xian

    2015-01-26

    Laparoscopic common bile duct exploration (LCBDE) for stone can be carried out by either laparoscopic transcystic stone extraction (LTSE) or laparoscopic choledochotomy (LC). It remains unknown as to which approach is optimal for management of gallbladder stone with common bile duct stones (CBDS) in Chinese patients. From May 2000 to February 2009, we prospective treated 346 consecutive patients with gallbladder stones and CBDS with laparoscopic cholecystectomy and LCBDE. Intraoperative findings, postoperative complications, postoperative hospital stay and costs were analyzed. Because of LCBDE failure,16 cases (4.6%) required open surgery. Of 330 successful LCBDE-treated patients, 237 underwent LTSE and 93 required LC. No mortality occurred in either group. The bile duct stone clearance rate was similar in both groups. Patients in the LTSE group were significantly younger and had fewer complications with smaller, fewer stones, shorter operative time and postoperative hospital stays, and lower costs, compared to those in the LC group. Compared with patients with T-tube insertion, patients in the LC group with primary closure had shorter operative time, shorter postoperative hospital stay, and lower costs. In cases requiring LCBDE, LTSE should be the first choice, whereas LC may be restricted to large, multiple stones. LC with primary closure without external drainage of the CBDS is as effective and safe as the T-tube insertion approach.

  3. The effectiveness of Stepping stones Triple P: the design of a randomised controlled trial on a parenting programme regarding children with mild intellectual disability and psychosocial problems versus care as usual

    OpenAIRE

    Kleefman, Marijke; Jansen, Daniëlle EMC; Reijneveld, Sijmen A

    2011-01-01

    Abstract Background Children with an intellectual disability are at increased risk of psychosocial problems. This leads to serious restrictions in the daily functioning of the children and to parental stress. Stepping Stones Triple P aims to prevent severe behavioural, emotional and developmental problems in children with a (intellectual) disability by enhancing parenting knowledge and skills, and the self-confidence of parents. This paper aims to describe the design of a study of the effecti...

  4. Ultrasonic propulsion of kidney stones.

    Science.gov (United States)

    May, Philip C; Bailey, Michael R; Harper, Jonathan D

    2016-05-01

    Ultrasonic propulsion is a novel technique that uses short bursts of focused ultrasonic pulses to reposition stones transcutaneously within the renal collecting system and ureter. The purpose of this review is to discuss the initial testing of effectiveness and safety, directions for refinement of technique and technology, and opinions on clinical application. Preclinical studies with a range of probes, interfaces, and outputs have demonstrated feasibility and consistent safety of ultrasonic propulsion with room for increased outputs and refinement toward specific applications. Ultrasonic propulsion was used painlessly and without adverse events to reposition stones in 14 of 15 human study participants without restrictions on patient size, stone size, or stone location. The initial feasibility study showed applicability in a range of clinically relevant situations, including facilitating passage of residual fragments following ureteroscopy or shock wave lithotripsy, moving a large stone at the ureteropelvic junction with relief of pain, and differentiating large stones from a collection of small fragments. Ultrasonic propulsion shows promise as an office-based system for transcutaneously repositioning kidney stones. Potential applications include facilitating expulsion of residual fragments following ureteroscopy or shock wave lithotripsy, repositioning stones prior to treatment, and repositioning obstructing ureteropelvic junction stones into the kidney to alleviate acute renal colic.

  5. Stepping Stone Mechanism: Carrier-Free Long-Range Magnetism Mediated by Magnetized Cation States in Quintuple Layer

    Science.gov (United States)

    Chan, Chunkai; Zhang, Xiaodong; Zhang, Yiou; Tse, Kinfai; Deng, Bei; Zhang, Jingzhao; Zhu, Junyi

    2018-01-01

    The long-range magnetism observed in group-V tellurides quintuple layers is the only working example of carrier-free dilute magnetic semiconductors (DMS), whereas the physical mechanism is unclear, except the speculation on the band topology enhanced van Vleck paramagnetism. Based on DFT calculations, we find a stable long-range ferromagnetic order in a single quintuple layer of Cr-doped Bi2Te3 or Sb2Te3, with the dopant separation more than 9 Å. This configuration is the global energy minimum among all configurations. Different from the conventional super exchange theory, the magnetism is facilitated by the lone pair derived anti-bonding states near the cations. Such anti-bonding states work as stepping stones merged in the electron sea and conduct magnetism. Further, spin orbit coupling induced band inversion is found to be insignificant in the magnetism. Therefore, our findings directly dismiss the common misbelief that band topology is the only factor that enhances the magnetism. We further demonstrate that removal of the lone pair derived states destroys the long-range magnetism. This novel mechanism sheds light on the fundamental understanding of long-range magnetism and may lead to discoveries of new classes of DMS. Supported by Chinese University of Hong Kong (CUHK) under Grant No 4053084, University Grants Committee of Hong Kong under Grant No 24300814, and the Start-up Funding of CUHK.

  6. Reliability of using nondestructive tests to estimate compressive strength of building stones and bricks

    Directory of Open Access Journals (Sweden)

    Ali Abd Elhakam Aliabdo

    2012-09-01

    Full Text Available This study aims to investigate the relationships between Schmidt hardness rebound number (RN and ultrasonic pulse velocity (UPV versus compressive strength (fc of stones and bricks. Four types of rocks (marble, pink lime stone, white lime stone and basalt and two types of burned bricks and lime-sand bricks were studied. Linear and non-linear models were proposed. High correlations were found between RN and UPV versus compressive strength. Validation of proposed models was assessed using other specimens for each material. Linear models for each material showed good correlations than non-linear models. General model between RN and compressive strength of tested stones and bricks showed a high correlation with regression coefficient R2 value of 0.94. Estimation of compressive strength for the studied stones and bricks using their rebound number and ultrasonic pulse velocity in a combined method was generally more reliable than using rebound number or ultrasonic pulse velocity only.

  7. Optimal Skin-to-Stone Distance Is a Positive Predictor for Successful Outcomes in Upper Ureter Calculi following Extracorporeal Shock Wave Lithotripsy: A Bayesian Model Averaging Approach.

    Directory of Open Access Journals (Sweden)

    Kang Su Cho

    Full Text Available To investigate whether skin-to-stone distance (SSD, which remains controversial in patients with ureter stones, can be a predicting factor for one session success following extracorporeal shock wave lithotripsy (ESWL in patients with upper ureter stones.We retrospectively reviewed the medical records of 1,519 patients who underwent their first ESWL between January 2005 and December 2013. Among these patients, 492 had upper ureter stones that measured 4-20 mm and were eligible for our analyses. Maximal stone length, mean stone density (HU, and SSD were determined on pretreatment non-contrast computed tomography (NCCT. For subgroup analyses, patients were divided into four groups. Group 1 consisted of patients with SSD<25th percentile, group 2 consisted of patients with SSD in the 25th to 50th percentile, group 3 patients had SSD in the 50th to 75th percentile, and group 4 patients had SSD≥75th percentile.In analyses of group 2 patients versus others, there were no statistical differences in mean age, stone length and density. However, the one session success rate in group 2 was higher than other groups (77.9% vs. 67.0%; P = 0.032. The multivariate logistic regression model revealed that shorter stone length, lower stone density, and the group 2 SSD were positive predictors for successful outcomes in ESWL. Using the Bayesian model-averaging approach, longer stone length, lower stone density, and group 2 SSD can be also positive predictors for successful outcomes following ESWL.Our data indicate that a group 2 SSD of approximately 10 cm is a positive predictor for success following ESWL.

  8. Quality Assessment of Urinary Stone Analysis

    DEFF Research Database (Denmark)

    Siener, Roswitha; Buchholz, Noor; Daudon, Michel

    2016-01-01

    After stone removal, accurate analysis of urinary stone composition is the most crucial laboratory diagnostic procedure for the treatment and recurrence prevention in the stone-forming patient. The most common techniques for routine analysis of stones are infrared spectroscopy, X-ray diffraction......, fulfilled the quality requirements. According to the current standard, chemical analysis is considered to be insufficient for stone analysis, whereas infrared spectroscopy or X-ray diffraction is mandatory. However, the poor results of infrared spectroscopy highlight the importance of equipment, reference...... spectra and qualification of the staff for an accurate analysis of stone composition. Regular quality control is essential in carrying out routine stone analysis....

  9. Surface detail reproduction and dimensional accuracy of stone models: influence of disinfectant solutions and alginate impression materials.

    Science.gov (United States)

    Guiraldo, Ricardo Danil; Borsato, Thaís Teixeira; Berger, Sandrine Bittencourt; Lopes, Murilo Baena; Gonini, Alcides; Sinhoreti, Mário Alexandre Coelho

    2012-01-01

    This study compared the surface detail reproduction and dimensional accuracy of stone models obtained from molds disinfected with 2% sodium hypochlorite, 2% chlorhexidine digluconate or 0.2% peracetic acid to models produced using molds which were not disinfected, with 3 alginate materials (Cavex ColorChange, Hydrogum 5 and Jeltrate Plus). The molds were prepared over matrix containing 20-, 50-, and 75-µm lines, performed under pressure with perforated metal tray. The molds were removed following gelation and either disinfected (using one of the solutions by spraying followed by storage in closed jars for 15 min) or not disinfected. The samples were divided into 12 groups (n=5). Molds were filled with dental gypsum Durone IV and 1 h after the start of the stone mixing the models were separated from the tray. Surface detail reproduction and dimensional accuracy were evaluated using optical microscopy on the 50-µm line with 25 mm in length, in accordance with the ISO 1563 standard. The dimensional accuracy results (%) were subjected to ANOVA. The 50 µm-line was completely reproduced by all alginate impression materials regardless of the disinfection procedure. There was no statistically significant difference in the mean values of dimensional accuracy in combinations between disinfectant procedure and alginate impression material (p=0.2130) or for independent factors. The disinfectant solutions and alginate materials used in this study are no factors of choice regarding the surface detail reproduction and dimensional accuracy of stone models.

  10. Significance of lower-pole pelvicaliceal anatomy on stone clearance after shockwave lithotripsy in nonobstructive isolated renal pelvic stones.

    Science.gov (United States)

    Sozen, Sinan; Kupeli, Bora; Acar, Cenk; Gurocak, Serhat; Karaoglan, Ustunol; Bozkirli, Ibrahim

    2008-05-01

    To investigate the probable effect of lower-pole pelvicaliceal anatomy on stone clearance after shockwave lithotripsy (SWL) in patients with nonobstructive renal pelvic stones. The clinical records of patients with isolated renal pelvic stones who underwent SWL between 1996 and 2005 were reviewed. After excluding patients with obstruction leading to dilatation, major anatomic abnormalities, noncalcium stones, metabolic abnormalities, history of recurrent stone disease, multiple stones, and previous renal surgery, 153 patients were enrolled in the study. Lower pole infundibulopelvic angle (IPA) and infundibular length and width were measured from intravenous urography. Patients were classified into three groups according to stone burden (group 1, renal pelvis, and both in 50 (32.6%), 29 (18.9%), and 8 (5.2%) patients, respectively. There was no statistically significant difference in pelvicaliceal anatomic features except narrower IPA (P=0.02) in group 1 patients with residual stones. The falling of stone fragments to the lower calix in spite of the ureter whether clinically significant or not after SWL of pelvic stones initially seems to be related to stone burden rather than lower caliceal anatomy. However, existence of a more narrow IPA in group 1 patients with residual fragments led us to believe that lower-pole IPA can play a role in stone clearance, especially for smaller stones, probably because of smaller residual fragment size or the more mobile nature of the primary stone.

  11. Use of the probability of stone formation (PSF) score to assess stone forming risk and treatment response in a cohort of Brazilian stone formers

    OpenAIRE

    Turney, Benjamin; Robertson, William; Wiseman, Oliver; Amaro, Carmen Regina P. R.; Leitão, Victor A.; Silva, Isabela Leme da; Amaro, João Luiz

    2014-01-01

    Introduction: The aim was to confirm that PSF (probability of stone formation) changed appropriately following medical therapy on recurrent stone formers.Materials and Methods: Data were collected on 26 Brazilian stone-formers. A baseline 24-hour urine collection was performed prior to treatment. Details of the medical treatment initiated for stone-disease were recorded. A PSF calculation was performed on the 24 hour urine sample using the 7 urinary parameters required: voided volume, oxalate...

  12. Endoscopic Stone Measurement During Ureteroscopy.

    Science.gov (United States)

    Ludwig, Wesley W; Lim, Sunghwan; Stoianovici, Dan; Matlaga, Brian R

    2018-01-01

    Currently, stone size cannot be accurately measured while performing flexible ureteroscopy (URS). We developed novel software for ureteroscopic, stone size measurement, and then evaluated its performance. A novel application capable of measuring stone fragment size, based on the known distance of the basket tip in the ureteroscope's visual field, was designed and calibrated in a laboratory setting. Complete URS procedures were recorded and 30 stone fragments were extracted and measured using digital calipers. The novel software program was applied to the recorded URS footage to obtain ureteroscope-derived stone size measurements. These ureteroscope-derived measurements were then compared with the actual-measured fragment size. The median longitudinal and transversal errors were 0.14 mm (95% confidence interval [CI] 0.1, 0.18) and 0.09 mm (95% CI 0.02, 0.15), respectively. The overall software accuracy and precision were 0.17 and 0.15 mm, respectively. The longitudinal and transversal measurements obtained by the software and digital calipers were highly correlated (r = 0.97 and 0.93). Neither stone size nor stone type was correlated with error measurements. This novel method and software reliably measured stone fragment size during URS. The software ultimately has the potential to make URS safer and more efficient.

  13. Toets van STONE versie 2.0. Samenvatting en belangrijkste resultaten

    NARCIS (Netherlands)

    Tiktak A; Beusen AHW; Boumans LJM; Groenedijk P; de Haan BJ; Portielje R; Schotten CGJ; Wolf J; LDL; IMP; Alterra; RIZA

    2003-01-01

    STONE is het landsdekkende nutrientenemissiemodel dat ontwikkeld is voor het evalueren van effecten van milieu- en landbouwbeleid op de belasting met stikstof en fosfaat van het grond- en oppervlaktewater. De commissie Spiertz vroeg in 2000 om validatie van dit model. Om deze reden werd de STONE

  14. Simplified methods for the evaluation of the risk of forming renal stones and the follow-up of stone-forming propensity during the preventive treatment of stone-formation.

    Science.gov (United States)

    Grases, Fèlix; Costa-Bauzá, Antonia

    2016-02-01

    Renal lithiasis is a complex multifactorial disease in which recurrence is common. Thus, simple and reliable procedures are needed to evaluate patients with previous kidney stones to determine the risk of recurrence. In this paper we review simple biochemical procedures that can be used to determine the risk for renal stone formation when the stone is available or unavailable for analysis. Our present knowledge of renal lithiasis indicates that renal stones form due to several well-defined factors. Analysis of the renal stone itself can provide important information about clinical factors that require further investigation. When the stone is unavailable, it is necessary to perform a general evaluation of main urinary risk factors associated to renal stone formation, but this study should be complemented considering information related to direct familial antecedents, recidivant degree, radiological images, medical history, and life style habits. Finally, tools for patient follow-up of stone-forming propensity during the preventive treatment are discussed .

  15. Effect of Stone Size and Composition on Ultrasonic Propulsion Ex Vivo.

    Science.gov (United States)

    Janssen, Karmon M; Brand, Timothy C; Bailey, Michael R; Cunitz, Bryan W; Harper, Jonathan D; Sorensen, Mathew D; Dunmire, Barbrina

    2018-01-01

    To evaluate in more detail the effectiveness of a new designed more efficient ultrasonic propulsion for large stones and specific stone compositions in a tissue phantom model. In the first clinical trial of noninvasive ultrasonic propulsion, urinary stones of unknown compositions and sizes up to 10 mm were successfully repositioned. The study included 8- to 12-mm stones of 4 different primary compositions (calcium oxalate monohydrate, ammonium acid urate, calcium phosphate, and struvite) and a renal calyx phantom consisting of a 12 mm × 30 mm well in a 10-cm block of tissue-mimicking material. Primary outcome was the number of times a stone was expelled over 10 attempts, with ultrasonic propulsion burst duration varying from 0.5 seconds to 5 seconds. Overall success rate at expelling stones was 95%. All calcium oxalate monohydrate and ammonium acid urate stones were expelled 100% of the time. The largest stone (12 mm) became lodged within the 12-mm phantom calyx 25% of the time regardless of the burst duration. With the 0.5-second burst, there was insufficient energy to expel the heaviest stone (0.88 g), but there was sufficient energy at the longer burst durations. With a single burst, ultrasonic propulsion successfully moved most stones at least 3 cm and, regardless of size or composition, expelled them from the calyx. Ultrasonic propulsion is limited to the stones smaller than the calyceal space, and for each burst duration, related to maximum stone mass. Published by Elsevier Inc.

  16. Compositions of stone and stone surface materials of historical monuments from Vidzeme and Zemgale

    International Nuclear Information System (INIS)

    Actins, A.; Spricis, A.; Zekunde, A.; Nemerova, A.

    2004-01-01

    By means of x-ray analysis composition of stone and stone surface materials of historical monuments from Vidzeme and Zemgale was investigated. Corrosion products of tuffa materials were identified on surfaces of some investigated monuments. Similarity of composition of products of stone corrosion for monuments from Latvia and Poland was recognised. Content of heavy metals at stone materials of historical monuments and at the surface layers of these monuments was investigated by means of atomic absorption and potentiometric stripping methods. Reasons of formation of compounds and pollution of investigated samples were discussed. (full text)

  17. Development of a laboratory model of a phototroph-heterotroph mixed-species biofilm at the stone/air interface

    Directory of Open Access Journals (Sweden)

    Federica eVilla

    2015-11-01

    Full Text Available Recent scientific investigations have shed light on the ecological importance and physiological complexity of subaerial biofilms (SABs inhabiting lithic surfaces. In the field of sustainable cultural heritage (CH preservation, mechanistic approaches aimed at investigation of the spatiotemporal patterns of interactions between the biofilm, the stone, and the atmosphere are of outstanding importance. However, these interactions have proven difficult to explore with field experiments due to the inaccessibility of samples, the complexity of the ecosystem under investigation and the temporal resolution of the experiments.To overcome these limitations, we aimed at developing a unifying methodology to reproduce a fast-growing, phototroph-heterotroph mixed species biofilm at the stone/air interface. Our experiments underscore the ability of the dual-species SAB model to capture functional traits characteristic of biofilms inhabiting lithic substrate such as: i microcolonies of aggregated bacteria; ii network like structure following surface topography; iii cooperation between phototrophs and heterotrophs and cross feeding processes; iv ability to change the chemical parameters that characterize the microhabitats; v survival under desiccation and vi biocide tolerance. With its advantages in control, replication, range of different experimental scenarios and matches with the real ecosystem, the developed model system is a powerful tool to advance our mechanistic understanding of the stone-biofilm-atmosphere interplay in different environments.

  18. Histopathology Predicts the Mechanism of Stone Formation

    Science.gov (United States)

    Evan, Andrew P.

    2007-04-01

    About 5% of American women and 12% of men will develop a kidney stone at some time in their life and these numbers appear to be on the rise. Despite years of scientific research into the mechanisms of stone formation and growth, limited advances have been made until recently. Randall's original observations and thoughts on the mechanisms for kidney stone formation have been validated for idiopathic calcium oxalate stone formers (ICSF) but not for most other stone forming groups. Our current studies on selected groups of human stone formers using intraoperative papillary biopsies has shown overwhelming evidence for the presence of Randall's plaque in ICSF and that stone formation and growth are exclusively linked to its availability to urinary ions and proteins. Intense investigation of the plaque-stone junction is needed if we are to understand the factors leading to the overgrowth process on exposed regions of plaque. Such information should allow the development of treatment strategies to block stone formation in ICSF patients. Patients who form brushite stones, or who form apatite stones because of distal renal tubular acidosis (dRTA), or patients with calcium oxalate stones due to obesity bypass procedures, or patients with cystinuria, get plugged inner medullary collecting ducts (IMCD) which leads to total destruction of the lining cells and focal sites of interstitial fibrosis. These stone formers have plaque but at levels equal to or below non-stone formers, which would suggest that they form stones by a different mechanism than do ICSF patients.

  19. Obesometric factors associated with increased skin-to-stone distances in renal stone patients.

    Science.gov (United States)

    Allard, Christopher B; Shuster, Anatoly; Pinthus, Jehonathan H; Farrokhyar, Forough; Raees, A; Patlas, Michael; Matsumoto, Edward D; Whelan, J Paul

    2012-12-01

    Obese patients are at increased risk for renal stones as well as treatment failures due to increased skin-to-stone distances (SSD) and harder stone compositions. We investigated the relationships between obesometric parameters (body mass index [BMI], body fat distribution and obesity-related hormone levels) with SSD and stone hardness. We prospectively enrolled patients undergoing stone interventions at our institution. Computed tomography (CT) scans were analyzed; adipose tissue was identified according to Hounsfield units (HU) and separated into subcutaneous (SAT) and visceral (VAT) components. The pixels were averaged at three levels to calculate fat distribution: %VAT = (VAT)/(VAT + SAT). SSD was measured and HU were used as a surrogate for stone hardness. Obesity-related hormones leptin and adiponectin were measured by ELISA. Seventy-nine patients were prospectively enrolled. Mean BMI and %VAT were 30.02 kg/m2 and 40.13 kg/m2. Mean leptin and adiponectin levels were 17.5 ng/mL and 7.67 mcg/mL indicating high risk for metabolic consequences of obesity. Females had greater proportions of subcutaneous fat than males (%VAT 28.4 versus 46.94, p r = 0.454, p = 0.008). Obese patients with %VAT > 40 versus stone compositions as measured by HU than non-diabetics (982.86 versus 648.86, p = 0.001). Obesometric parameters such as BMI, body fat distribution, and the presence of diabetes mellitus are important considerations in the management of renal stone disease. A large proportion of subcutaneous fat, which can be estimated by physical examination, predicts SSD among obese patients and may aid treatment decisions in patients, particularly those without pre-treatment CT scans. Further studies are needed to refine the role of obesometrics in personalizing treatment decisions.

  20. Archaeomagnetic studies of Maori Hangi Stones from New Zealand

    Science.gov (United States)

    Kinger, R.; Turner, G. M.; McFadgen, B.

    2014-12-01

    Global palaeosecular variation models still suffer from a paucity of high quality data from the SW Pacific region. Over the past two years we have worked to fill this gap with archaeomagnetic data - directions and palaeointensities - by studying the thermoremanent magnetization of Maori hangi cooking stones. Used as heat retainers, these stones are heated, frequently above the Curie temperatures of constituent magnetic minerals, before being buried in earth ovens. After removal of the food, hangi sites are often abandoned with the stones still in situ, carrying a record of the magnetic field in which they were last cooled. We have sampled a range of archaeological hangi sites throughout New Zealand, dating to early prehistoric times (ca 700 BP). The stones vary in lithology from andesites, originating from the central North Island volcanoes, favoured by Maori for their durability and with NRM intensities up to 30 A/m, to greywackes and schists from the main axial ranges, with NRMs as weak as 10-4A/m. In all cases, we have independently oriented and retrieved several stones, and we have made several specimens from each stone, either by drilling (standard cylindrical specimens) or sawing (pseudo-cubes) in the laboratory. We have calculated site mean palaeomagnetic directions from principal component analysis of thermal demagnetization data, discarding the data of stones that show evidence of disturbance. We have carried out palaeointensity experiments using a Coe/Thellier method with pTRM and tail checks, and with selection criteria modified to the situation. Rock magnetic experiments contribute to our understanding of the mineralogy, domain state and blocking temperature spectra. The palaeodirections fall between declinations of 348o and 24.5o, and inclinations of -46.4o and -72.4o, with palaeointensities between 43.7±1.4 and 81.3±6.1 mT. Most fall within the expected range of secular variation for New Zealand. However the palaeointensity of 81.34±6.08mT, from an

  1. Some considerations concerning volume-modulated arc therapy: a stepping stone towards a general theory

    International Nuclear Information System (INIS)

    Webb, S; McQuaid, D

    2009-01-01

    In this paper it is formally shown that the dynamic multileaf collimator (MLC) IMRT delivery technique remains valid if the MLC is supported on a 1D moving platform. It is also shown that, in such circumstances, it is always time preferable to deliver overlapping modulating fields as a single swept field rather than as separate fields. The most general formulism is presented and then related to simpler equations in limiting cases. The paper explains in detail how a 'small-arc approximation' can be invoked to relate the 1D linear theory to the MLC-on-moving-platform-(gantry) delivery technique involving rotation therapy and known as volume-modulated arc therapy (VMAT). It is explained how volume-modulated arc therapy delivered with open unmodulated fields and which can deliver conformal dose distributions can be interpreted as an IMRT delivery. The (Elekta adopted) term VMAT will be used in a generic sense to include a similar (Varian) method known as RapidArc. Approximate expressions are derived for the 'amount of modulation' possible in a VMAT delivery. This paper does not discuss the actual VMAT planning but gives an insight at a deep level into VMAT delivery. No universal theory of VMAT is known in the sense that there is no theory that can predict precisely the performance of a VMAT delivery in terms of the free parameters available (variable gantry speed, variable fluence-delivery rate, set of MLC shapes, MLC orientation, number of arcs, coplanarity versus non-coplanarity, etc). This is in stark contrast to the situation with several other IMRT delivery techniques where such theoretical analyses are known. In this paper we do not provide such a theory; the material presented is a stepping stone on the path towards this.

  2. Can stone density on plain radiography predict the outcome of extracorporeal shockwave lithotripsy for ureteral stones?

    Science.gov (United States)

    Lim, Ki Hong; Jung, Jin-Hee; Kwon, Jae Hyun; Lee, Yong Seok; Bae, Jungbum; Cho, Min Chul; Lee, Kwang Soo

    2015-01-01

    Purpose The objective was to determine whether stone density on plain radiography (kidney-ureter-bladder, KUB) could predict the outcome of extracorporeal shockwave lithotripsy (ESWL) for ureteral stones. Materials and Methods A total of 223 patients treated by ESWL for radio-opaque ureteral stones of 5 to 20 mm were included in this retrospective study. All patients underwent routine blood and urine analyses, plain radiography (KUB), and noncontrast computed tomography (NCCT) before ESWL. Demographic, stone, and radiological characteristics on KUB and NCCT were analyzed. The patients were categorized into two groups: lower-density (LD) group (radiodensity less than or equal to that of the 12th rib, n=163) and higher-density (HD) group (radiodensity greater than that of the 12th rib, n=60). Stone-free status was assessed by KUB every week after ESWL. A successful outcome was defined as stone free within 1 month after ESWL. Results Mean stone size in the LD group was significantly smaller than that in the HD group (7.5±1.4 mm compared with 9.9±2.9 mm, p=0.002). The overall success rates in the LD and HD groups were 82.1% and 60.0%, respectively (p=0.007). The mean duration of stone-free status and average number of SWL sessions required for success in the two groups were 21.7 compared with 39.2 days and 1.8 compared with 2.3, respectively (pESWL since colic and radiodensity of the stone on KUB were independent predictors of successful ESWL. Conclusions Our data suggest that larger stone size, longer time to ESWL, and ureteral stones with a radiodensity greater than that of the 12th rib may be at a relatively higher risk of ESWL failure 1 month after the procedure. PMID:25598937

  3. Trends in urological stone disease.

    Science.gov (United States)

    Turney, Benjamin W; Reynard, John M; Noble, Jeremy G; Keoghane, Stephen R

    2012-04-01

    To summarize the changes in prevalence and treatment of upper urinary tract stone disease in the UK over the last 10 years. Data from the Hospital Episode Statistics (HES) website (http://www.hesonline.nhs.uk) were extracted, summarized and presented. The number of upper urinary tract stone hospital episodes increased by 63% to 83,050 in the 10-year period. The use of shock wave lithotripsy (SWL) for treating all upper tract stones increased from 14,491 cases in 2000-2001 to 22,402 cases in 2010 (a 55% increase) with a 69% increase in lithotripsy for renal stones. There was a 127% increase in the number of ureteroscopic stone treatments from 6,283 to 14,242 cases over the 10-year period with a 49% increase from 2007/2008 to 2009/2010. There was a decline in open surgery for upper tract stones from 278 cases in 2000/2001 to 47 cases in 2009/2010 (an 83% reduction). Treatment for stone disease has increased substantially in comparison with other urological activity. In 2009/2010, SWL was performed almost as frequently as transurethral resection of the prostate or transurethral resection of bladder tumour, ureteroscopy for stones was performed more frequently than nephrectomy, radical prostatectomy and cystectomy combined, and percutaneous nephrolithotomy was performed more frequently than cystectomy. The present study highlights the increase in prevalence and treatment of stone disease in the UK over the last 10 years. If this trend continues it has important implications for workforce planning, training, service delivery and research in the field of urolithiasis. © 2011 THE AUTHORS. BJU INTERNATIONAL © 2011 BJU INTERNATIONAL.

  4. Fasting and Urinary Stones

    Directory of Open Access Journals (Sweden)

    Ali Shamsa

    2013-11-01

    Full Text Available Introduction: Fasting is considered as one of the most important practices of Islam, and according to Prophet Mohammad, fasting is obligatory upon Muslims. The aim of this study is to evaluate the effects of fasting on urinary stones. Materials and Methods: Very few studies have been carried out on urinary stones and the effect of Ramadan fasting. The sources of the present study are Medline and articles presented by local and Muslim researchers. Meanwhile, since we are acquainted with three well-known researchers in the field of urology, we contacted them via email and asked for their professional opinions. Results: The results of studies about the relationship of urinary stones and their incidence in Ramadan are not alike, and are even sometimes contradictory. Some believe that increased incidence of urinary stones in Ramadan is related not to fasting, but to the rise of weather temperature in hot months, and an increase in humidity. Conclusion: Numerous biological and behavioral changes occur in people who fast in Ramadan and some researchers believe that urinary stone increases during this month.

  5. The economics of stone disease.

    Science.gov (United States)

    Canvasser, Noah E; Alken, Peter; Lipkin, Michael; Nakada, Stephen Y; Sodha, Hiren S; Tepeler, Abdulkadir; Lotan, Yair

    2017-09-01

    The rising prevalence of kidney stone disease is associated with significant costs to healthcare systems worldwide. This is in part due to direct procedural and medical management costs, as well as indirect costs to health systems, patients, and families. A number of manuscripts evaulating the economics of stone disease have been published since the 2008s International Consultation on Stone Disease. These highlight costs associated with stone disease, including acute management, surgical management, and medical management. This work hopes to highlight optimization in care by reducing inefficient treatments and maximizing cost-efficient preventative strategies.

  6. NUMERICAL MODELLING AS NON-DESTRUCTIVE METHOD FOR THE ANALYSES AND DIAGNOSIS OF STONE STRUCTURES: MODELS AND POSSIBILITIES

    Directory of Open Access Journals (Sweden)

    Nataša Štambuk-Cvitanović

    1999-12-01

    Full Text Available Assuming the necessity of analysis, diagnosis and preservation of existing valuable stone masonry structures and ancient monuments in today European urban cores, numerical modelling become an efficient tool for the structural behaviour investigation. It should be supported by experimentally found input data and taken as a part of general combined approach, particularly non-destructive techniques on the structure/model within it. For the structures or their detail which may require more complex analyses three numerical models based upon finite elements technique are suggested: (1 standard linear model; (2 linear model with contact (interface elements; and (3 non-linear elasto-plastic and orthotropic model. The applicability of these models depend upon the accuracy of the approach or type of the problem, and will be presented on some characteristic samples.

  7. Regional differences in constituents of gall stones.

    Science.gov (United States)

    Ashok, M; Nageshwar Reddy, D; Jayanthi, V; Kalkura, S N; Vijayan, V; Gokulakrishnan, S; Nair, K G M

    2005-01-01

    The pathogenesis of pigment and mixed gall stone formation remains elusive. The elemental constituents of gall stones from southern states of Tamil Nadu, Kerala and Karnataka have been characterized. Our aim was to determine the elemental concentration of representative samples of pigment, mixed and cholesterol gall stones from Andhra Pradesh using proton-induced X-ray emission (PIXE) using a 3 MV horizontal pelletron accelerator. Pigment gall stones had significantly high concentrations of copper, iron and lead; chromium was absent. Except for iron all these elements were significantly low in cholesterol gall stones and intermediate levels were seen in mixed gall stones. Highest concentrations of chromium was seen in cholesterol and titanium in mixed gall stones respectively; latter similar to other southern states. Arsenic was distinctly absent in cholesterol and mixed gall stones. The study has identified differences in elemental components of the gall stones from Andhra Pradesh.

  8. The bioreceptivity of building stone

    Science.gov (United States)

    Mauko Pranjić, Alenka; Mulec, Janez; Muck, Tadeja; Hladnik, Aleš; Mladenovič, Ana

    2015-04-01

    Bioreceptivity is an intrinsic property of stone, and is defined as the ability of a material to be colonized by living organisms. The fouling and staining of building stone material due to the activity of microorganisms presents a serious problem in modern as well as historical buildings, not only due to the aesthetic impact but also due to the deterioration of the material. Biological colonisation on stone materials is influenced by a number of factors, e.g. the intrinsic properties of the stone (porosity, roughness, permeability, mineral composition), environmental parameters (e.g. solar radiation, temperature, water regime, climate, etc.), and specific microclimatic parameters (e.g. orientation, exposure to shadow, permanent capillary humidity, etc.). In order to assess the bioreceptivity of building stones, use is often made of artificial colonisation experiments compromising the inoculation of stones with a single species or a few isolated strains under laboratory conditions. In the present work the authors present the development of a method for the determination of bioreceptivity, as well as a study of the bioreceptivity of selected natural stone versus the latter's intrinsic properties. Field examples of biodeterioration are also presented. The study was supported by the Slovenian Research Agency (L1-5453).

  9. Upper urinary tract stone disease in patients with poor performance status: active stone removal or conservative management?

    Science.gov (United States)

    Yamashita, Shimpei; Kohjimoto, Yasuo; Hirabayashi, Yasuo; Iguchi, Takashi; Iba, Akinori; Higuchi, Masatoshi; Koike, Hiroyuki; Wakamiya, Takahito; Nishizawa, Satoshi; Hara, Isao

    2017-11-16

    It remains controversial as to whether active stone removal should be performed in patients with poor performance status because of their short life expectancy and perioperative risks. Our objectives were to evaluate treatment outcomes of active stone removal in patients with poor performance status and to compare life prognosis with those managed conservatively. We retrospectively reviewed 74 patients with Eastern Cooperative Oncology Group performance status 3 or 4 treated for upper urinary tract calculi at our four hospitals between January 2009 and March 2016. Patients were classified into either surgical treatment group or conservative management group based on the presence of active stone removal. Stone-free rate and perioperative complications in surgical treatment group were reviewed. In addition, we compared overall survival and stone-specific survival between the two groups. Cox proportional hazards analysis was performed to investigate predictors of overall survival and stone-specific survival. Fifty-two patients (70.3%) underwent active stone removal (surgical treatment group) by extracorporeal shock wave lithotripsy (n = 6), ureteroscopy (n = 39), percutaneous nephrolithotomy (n = 6) or nephrectomy (n = 1). The overall stone-free rate was 78.8% and perioperative complication was observed in nine patients (17.3%). Conservative treatment was undergone by 22 patients (29.7%) (conservative management group). Two-year overall survival rates in surgical treatment and conservative management groups were 88.0% and 38.4%, respectively (p performance status could be performed safely and effectively. Compared to conservative management, surgical stone treatment achieved longer overall survival and stone-specific survival.

  10. Two-step variable selection in quantile regression models

    Directory of Open Access Journals (Sweden)

    FAN Yali

    2015-06-01

    Full Text Available We propose a two-step variable selection procedure for high dimensional quantile regressions, in which the dimension of the covariates, pn is much larger than the sample size n. In the first step, we perform ℓ1 penalty, and we demonstrate that the first step penalized estimator with the LASSO penalty can reduce the model from an ultra-high dimensional to a model whose size has the same order as that of the true model, and the selected model can cover the true model. The second step excludes the remained irrelevant covariates by applying the adaptive LASSO penalty to the reduced model obtained from the first step. Under some regularity conditions, we show that our procedure enjoys the model selection consistency. We conduct a simulation study and a real data analysis to evaluate the finite sample performance of the proposed approach.

  11. Management of ureteric stone in pediatric patients

    Directory of Open Access Journals (Sweden)

    Eugene Minevich

    2010-01-01

    Full Text Available The management of ureteral stones in children is becoming more similar to that in adults. A number of factors must be taken into account when selecting one′s choice of therapy for ureteral stone in children such as the size of the stone, its location, its composition, and urinary tract anatomy. Endoscopic lithotripsy in children has gradually become a major technique for the treatment of ureteral stones. The stone-free rate following urteroscopic lithotripsy for ureteral stones has been reported in as high as 98.5-100%. The safety and efficacy of Holmium:YAG laser lithotripsy make it the intracorporeal lithotriptor of choice. Given its minimally invasive features, extracorporeal shock wave lithotripsy (ESWL has become a primary mode of treatment for the pediatric patients with reno-ureteral stones. Stone-free rates have been reported from 59% to 91% although some patients will require more than one treatment session for stone clearance. It appears that the first-line of therapy in the child with distal and mid-ureteral stones should be ureteroscopic lithotripsy. While ESWL is still widely considered the first-line therapy for proximal ureteral calculi, there is an increasing body of evidence that shows that endoscopic or ESWL are equally safe and efficacious in those clinical scenarios. Familiarity with the full spectrum of endourological techniques facilitates a minimally invasive approach to pediatric ureteral stones.

  12. Analysis of urinary stone based on a spectrum absorption FTIR-ATR

    International Nuclear Information System (INIS)

    Asyana, V; Haryanto, F; Fitri, L A; Ridwan, T; Anwary, F; Soekersi, H

    2016-01-01

    This research analysed the urinary stone by measuring samples using Fourier transform infrared-attenuated total reflection spectroscopy and black box analysis. The main objective of this study is to find kinds of urinary stone and determine a total spectrum, which is a simple model of the chemical and mineral composition urinary stone through black box analysis using convolution method. The measurements result showed that kinds of urinary stone were pure calcium oxalate monohydrate, ion amino acid calcium oxalate monohydrate, a mixture of calcium oxalate monohydrate with calcium phosphate, a mixture of ion amino acid calcium oxalate monohydrate and calcium phosphate,pure uric acid, ion amino acid uric acid, and a mixture of calcium oxalate monohydrate with ion amino acid uric acid. The results of analysis of black box showed characteristics as the most accurate and precise to confirm the type of urinary stones based on theregion absorption peak on a graph, the results of the convolution, and the shape of the total spectrum on each urinary stones. (paper)

  13. Correlation between Copper, Zinc and some lipids in serum, bile and stones of patients with gall stone disease

    International Nuclear Information System (INIS)

    Abu-Farsakh, F.

    1997-01-01

    Measurements of Cu, Zn and some lipid concentrations were carried out in serum, bile and gall stone samples collected from 76 patients undergoing surgery for removal of gall stones. The results showed that Cu and Zn were present in micromolar concentration in bile (average Cu concentration = 13.4 ± 0.92, average Zn concentration = 13.4 ± 1.05) and gall stones (average Cu concentration = 2.8 ± 0.16, average Zn concentration = 1.8 ± 0.16 mmol/ g stone). Cross-tabulation of the results showed significant positive linear correlations (p< 0.01) between stone Zn vs. bile cholesterol (r = 0.253), stone Zn vs. bile bilirubin (r = 0.396) (in mixed stones only). This suggested that the more hydrophobic the bile sample, the more Zn co-precipitate with cholesterol or bilirubin. (author). 17 refs., 3 tabs

  14. Systematic Review and Meta-analysis of Stepping Stones Triple P for Parents of Children with Disabilities.

    Science.gov (United States)

    Ruane, AIlbhe; Carr, Alan

    2018-03-09

    The aim of this systematic review and meta-analysis was to examine the effectiveness of Stepping Stones Triple P (SSTP) parent training programs on child behavior problems and parenting outcomes in families of children with developmental disabilities. Sixteen suitable studies including data from over 900 families were identified in a search for English language published and unpublished controlled outcome studies. SSTP has five levels on a graded continuum of increasing intensity targeting families with differing degrees of treatment need from low intensity media-based parenting information campaigns at level 1, through brief interventions at levels 2 and 3, to more intensive parent training and family therapy interventions at levels 4 and 5. Analyses were conducted on the combination of all levels of SSTP and separately for each level. For combined levels, significant overall effect sizes were found for parent-reported child problems (d = 0.46), researcher observed child behavior (d = 0.51), parenting style (d = 0.70), parenting satisfaction/self-efficacy (d = 0.44), parental adjustment (d = 0.27), and coparental relationship (d = 0.26), but not researcher-observed parent behavior. Strong support was found for level 4 SSTP as an effective intervention for improving child and parent outcomes in families of children with disabilities who have clinically significant problems. Less intensive SSTP interventions for cases with circumscribed difficulties yielded fewer significant treatment effects, and there were relatively few studies of such interventions. © 2018 Family Process Institute.

  15. Advances in percutaneous stone surgery

    OpenAIRE

    Hartman, Christopher; Gupta, Nikhil; Leavitt, David; Hoenig, David; Okeke, Zeph; Smith, Arthur

    2015-01-01

    Treatment of large renal stones has changed considerably in recent years. The increasing prevalence of nephrolithiasis has mandated that urologists perform more surgeries for large renal calculi than before, and this has been met with improvements in percutaneous stone surgery. In this review paper, we examine recent developments in percutaneous stone surgery, including advances in diagnosis and preoperative planning, renal access, patient position, tract dilation, nephroscopes, lithotripsy, ...

  16. Diffraction model of a step-out transition

    Energy Technology Data Exchange (ETDEWEB)

    Chao, A.W.; Zimmermann, F.

    1996-06-01

    The diffraction model of a cavity, suggested by Lawson, Bane and Sands is generalized to a step out transition. Using this model, the high frequency impedance is calculated explicitly for the case that the transition step is small compared with the beam pipe radius. In the diffraction model for a small step out transition, the total energy is conserved, but, unlike the cavity case, the diffracted waves in the geometric shadow and the pipe region, in general, do not always carry equal energy. In the limit of small step sizes, the impedance derived from the diffraction model agrees with that found by Balakin, Novokhatsky and also Kheifets. This impedance can be used to compute the wake field of a round collimator whose half aperture is much larger than the bunch length, as existing in the SLC final focus.

  17. PIXE analysis of chinese chicken-blood stone

    International Nuclear Information System (INIS)

    Lin, E.K.; Wang, C.W.; Yu, Y.C.; Liu, T.Y.; Cheng, H.S.; Zhu, H.X.; Yang, H.J.

    1999-01-01

    This paper reports the chemical compositions of chicken-blood stone Ji Xue Shi measured by Proton Induced X-ray Emission (PIXE). The experimental result show that for the red portion of chicken-blood stone, the concentration of Hg is as high as 20 wt%, and the concentration of S can be above 10 wt%. For the non-red portion the main chemical compositions are Al 2 O 3 and SiO 2 . The obtained chemical compositions are close to those of kaolinite for Balin chicken-blood stone, and of pyrophyllite for Changhua chicken-blood stone, respectively. So far many Changhua chicken-blood stones and Balin chicken-blood stones were found in China, the PIXE method can be used to explore the provenance of available chicken-blood stones. (author)

  18. Assessment of Influence of Contact Time between Alginate and Type III Dental Stone on Properties of Cast Model: An in vitro Study.

    Science.gov (United States)

    Dev, Shruti; Kar, Aswini K; Garhnayak, Mirna; Garhnayak, Lokanath; Dhal, Angurbala

    2017-10-01

    Alginate is a versatile, irreversible hydrocolloid impression material, which is cost-effective and forms an essential component in dental practice. For elevating the hardness of the cast models, hardeners are combined with stone. Hence, we planned the present study to evaluate the impact of altering the time of contact between alginate and stone after various interim periods. The present study included the assessment of impact of time of contact between alginate and stone by the construction of 90 casts using a cylinder model. Two bisecting lines were marked and were named as y and y'. These lines were used for testing the dimensional stability. Using chemically cured acrylic resin, the construction of ten special trays was done. All the impression casts were randomly divided into two study groups, with 45 casts in each group-group I: control group, casts were removed after 60 minutes; group II: study group, casts were removed after 9 hours. A digital caliper was used for measuring the dimensional stability of the cast. All the data were collected and analyzed. In the specimens of the control group (group I) and the study group (group II), the mean dimensions from y to y' were found to be 17.54 and 17.95 respectively. The mean reading of hardness in the control group and study group was found to be 0.59 and 0.20 respectively. In groups I and II, the number of specimens showing clarity of two lines (X and X") was 0 and 5 respectively. There was no change in the dimensional stability of the dental stone model when the contact time was increased. Within certain limits, the contact time between alginate and stone can be altered without significantly altering the properties of the cast.

  19. Optimum nutrition for kidney stone disease.

    Science.gov (United States)

    Heilberg, Ita P; Goldfarb, David S

    2013-03-01

    We summarize the data regarding the associations of individual dietary components with kidney stones and the effects on 24-hour urinary profiles. The therapeutic recommendations for stone prevention that result from these studies are applied where possible to stones of specific composition. Idiopathic calcium oxalate stone-formers are advised to reduce ingestion of animal protein, oxalate, and sodium while maintaining intake of 800 to 1200 mg of calcium and increasing consumption of citrate and potassium. There are few data regarding dietary therapy of calcium phosphate stones. Whether the inhibitory effect of citrate sufficiently counteracts increasing urine pH to justify more intake of potassium and citrate is not clear. Reduction of sodium intake to decrease urinary calcium excretion would also be expected to decrease calcium phosphate stone recurrence. Conversely, the most important urine variable in the causation of uric acid stones is low urine pH, linked to insulin resistance as a component of obesity and the metabolic syndrome. The mainstay of therapy is weight loss and urinary alkalinization provided by a more vegetarian diet. Reduction in animal protein intake will reduce purine ingestion and uric acid excretion. For cystine stones, restriction of animal protein is associated with reduction in intake of the cystine precursor methionine as well as cystine. Reduction of urine sodium results in less urine cystine. Ingestion of vegetables high in organic anion content, such as citrate and malate, should be associated with higher urine pH and fewer stones because the amino acid cystine is soluble in more alkaline urine. Because of their infectious origin, diet has no definitive role for struvite stones except for avoiding urinary alkalinization, which may worsen their development. Published by Elsevier Inc.

  20. ORIGINAL PAPER ORIG ORIG Percutaneous stone removal

    African Journals Online (AJOL)

    Percutaneous nephrolithotomy (PCNL) is an effective procedure to treat patients with complex renal stones,. e.g. staghorn calculi and stones greater than 20 mm in diameter. The treatment of choice for small, less com- plex renal stones is extracorporeal shock-wave litho- tripsy (ESWL).1 We have treated renal stones mainly.

  1. Model experiment of in vivo synchrotron X-ray diffraction of human kidney stones

    Energy Technology Data Exchange (ETDEWEB)

    Ancharov, A.I. [Institute of Solid State Chemistry and Mechanochemistry SB RAS, Novosibirsk (Russian Federation)]. E-mail: ancharov@mail.ru; Potapov, S.S. [Institute of Mineralogy UB RAS, Miass (Russian Federation); Moiseenko, T.N. [The State Regional Clinical Hospital, Novosibirsk (Russian Federation); Feofilov, I.V. [The State Regional Clinical Hospital, Novosibirsk (Russian Federation); Nizovskii, A.I. [Boreskov Institute of Catalysis SB RAS, Novosibirsk (Russian Federation)

    2007-05-21

    The diffraction of synchrotron radiation (SR) was used to explore the phase composition of kidney stones placed into a specific object phantom, which imitated the human body. As an imitation of the patient breath, the kidney stone was moved vertically and rotated to an angle of 15{sup o} during the recording of the X-ray pattern. It was shown that rotation and displacement did not distort the X-ray pattern.

  2. Model experiment of in vivo synchrotron X-ray diffraction of human kidney stones

    International Nuclear Information System (INIS)

    Ancharov, A.I.; Potapov, S.S.; Moiseenko, T.N.; Feofilov, I.V.; Nizovskii, A.I.

    2007-01-01

    The diffraction of synchrotron radiation (SR) was used to explore the phase composition of kidney stones placed into a specific object phantom, which imitated the human body. As an imitation of the patient breath, the kidney stone was moved vertically and rotated to an angle of 15 o during the recording of the X-ray pattern. It was shown that rotation and displacement did not distort the X-ray pattern

  3. Stone Soup Partnership: A Grassroots Model of Community Service.

    Science.gov (United States)

    Kittredge, Robert E.

    1997-01-01

    Stone Soup Partnership is a collaboration between California State University at Fresno and its surrounding community to address serious problems in a high-crime, impoverished apartment complex near the university. The program involves students in service learning for university credit, and has expanded from a single summer youth program to a…

  4. The construction of geological model using an iterative approach (Step 1 and Step 2)

    International Nuclear Information System (INIS)

    Matsuoka, Toshiyuki; Kumazaki, Naoki; Saegusa, Hiromitsu; Sasaki, Keiichi; Endo, Yoshinobu; Amano, Kenji

    2005-03-01

    One of the main goals of the Mizunami Underground Research Laboratory (MIU) Project is to establish appropriate methodologies for reliably investigating and assessing the deep subsurface. This report documents the results of geological modeling of Step 1 and Step 2 using the iterative investigation approach at the site-scale (several 100m to several km in area). For the Step 1 model, existing information (e.g. literature), and results from geological mapping and reflection seismic survey were used. For the Step 2 model, additional information obtained from the geological investigation using existing borehole and the shallow borehole investigation were incorporated. As a result of this study, geological elements that should be represented in the model were defined, and several major faults with trends of NNW, EW and NE trend were identified (or inferred) in the vicinity of the MIU-site. (author)

  5. 77 FR 27245 - Big Stone National Wildlife Refuge, Big Stone and Lac Qui Parle Counties, MN

    Science.gov (United States)

    2012-05-09

    ... DEPARTMENT OF THE INTERIOR Fish and Wildlife Service [FWS-R3-R-2012-N069; FXRS1265030000S3-123-FF03R06000] Big Stone National Wildlife Refuge, Big Stone and Lac Qui Parle Counties, MN AGENCY: Fish and... plan (CCP) and environmental assessment (EA) for Big Stone National Wildlife Refuge (Refuge, NWR) for...

  6. The effect of inclined position on stone free rates in patients with lower caliceal stones during SWL session

    Directory of Open Access Journals (Sweden)

    Basri Cakiroglu

    2015-03-01

    Full Text Available Objective: To compare the outcomes of shock wave lithotripsy (SWL combined with inclined position and SWL alone in patients with lower pole calyx stones. Methods: Seven hundred forty patients who underwent SWL treatment for lower pole renal stones with a total diameter of 2 cm or less were prospectively randomized into two groups. They were comparable in terms of age, sex, and stone diameters. Patients with lower calyceal stones (4-20 mm were randomized to SWL (368 patients or SWL with simultaneous inclination (372 patients with 30o head down Trendelenburg position. Shock wave and session numbers were standardized according to stone size. Additional standardized shock waves were given to patients with stone fragments determined by kidney urinary bladder film and ultrasound at weeks 1, 4, 10. Results: The overall stone free rate (SFR was 73% (268/368 in patients with SWL alone and 81% (300/372 in SWL with inclination at the end of 12th week (p = 0.015. No significant adverse events were noted in both treatment groups. Conclusion: Simultaneous inclination of patients during SWL session increase SFR in lower caliceal stones significantly compared to SWL treatment alone.

  7. Stone comminution correlates with the average peak pressure incident on a stone during shock wave lithotripsy.

    Science.gov (United States)

    Smith, N; Zhong, P

    2012-10-11

    To investigate the roles of lithotripter shock wave (LSW) parameters and cavitation in stone comminution, a series of in vitro fragmentation experiments have been conducted in water and 1,3-butanediol (a cavitation-suppressive fluid) at a variety of acoustic field positions of an electromagnetic shock wave lithotripter. Using field mapping data and integrated parameters averaged over a circular stone holder area (R(h)=7 mm), close logarithmic correlations between the average peak pressure (P(+(avg))) incident on the stone (D=10 mm BegoStone) and comminution efficiency after 500 and 1000 shocks have been identified. Moreover, the correlations have demonstrated distinctive thresholds in P(+(avg)) (5.3 MPa and 7.6 MPa for soft and hard stones, respectively), that are required to initiate stone fragmentation independent of surrounding fluid medium and LSW dose. These observations, should they be confirmed using other shock wave lithotripters, may provide an important field parameter (i.e., P(+(avg))) to guide appropriate application of SWL in clinics, and facilitate device comparison and design improvements in future lithotripters. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. The competitiveness of small and medium sized enterprises of stone industry

    Directory of Open Access Journals (Sweden)

    Nikraftar Tayebeh

    2016-01-01

    Full Text Available This study aims to examine the antecedents of stone firms competitiveness based on Porter's model. Questionnaire data collected from 200 senior stone firms' members in Iran. The results show that all aspects of porter model have positive effects on competitiveness. Also, factor conditions contributed significantly to enterprises competitiveness and are the most important predictor among all other of the antecedents of competitiveness. Because the data is limited to stone industry, future studies need to validate these results in other industries. The findings of this study suggest that, to increase competitiveness ability, the stone firms should invest in developing and enhancing factor conditions. The value of this paper lies in its contribution to understanding better the predictors of competitiveness. Particularly, the paper adds to the existing literature by showing that the key success factors for competitiveness are factor and demand conditions. People who want to work for the industry should promote the factor and demand conditions. It is better that they work in the areas which have enough demand and factor conditions.

  9. Do Urinary Cystine Parameters Predict Clinical Stone Activity?

    Science.gov (United States)

    Friedlander, Justin I; Antonelli, Jodi A; Canvasser, Noah E; Morgan, Monica S C; Mollengarden, Daniel; Best, Sara; Pearle, Margaret S

    2018-02-01

    An accurate urinary predictor of stone recurrence would be clinically advantageous for patients with cystinuria. A proprietary assay (Litholink, Chicago, Illinois) measures cystine capacity as a potentially more reliable estimate of stone forming propensity. The recommended capacity level to prevent stone formation, which is greater than 150 mg/l, has not been directly correlated with clinical stone activity. We investigated the relationship between urinary cystine parameters and clinical stone activity. We prospectively followed 48 patients with cystinuria using 24-hour urine collections and serial imaging, and recorded stone activity. We compared cystine urinary parameters at times of stone activity with those obtained during periods of stone quiescence. We then performed correlation and ROC analysis to evaluate the performance of cystine parameters to predict stone activity. During a median followup of 70.6 months (range 2.2 to 274.6) 85 stone events occurred which could be linked to a recent urine collection. Cystine capacity was significantly greater for quiescent urine than for stone event urine (mean ± SD 48 ± 107 vs -38 ± 163 mg/l, p stone activity (r = -0.29, p r = -0.88, p r = -0.87, p stone quiescence. Decreasing the cutoff to 90 mg/l or greater improved sensitivity to 25.2% while maintaining specificity at 90.9%. Our results suggest that the target for capacity should be lower than previously advised. Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  10. Advances in percutaneous stone surgery.

    Science.gov (United States)

    Hartman, Christopher; Gupta, Nikhil; Leavitt, David; Hoenig, David; Okeke, Zeph; Smith, Arthur

    2015-01-01

    Treatment of large renal stones has changed considerably in recent years. The increasing prevalence of nephrolithiasis has mandated that urologists perform more surgeries for large renal calculi than before, and this has been met with improvements in percutaneous stone surgery. In this review paper, we examine recent developments in percutaneous stone surgery, including advances in diagnosis and preoperative planning, renal access, patient position, tract dilation, nephroscopes, lithotripsy, exit strategies, and post-operative antibiotic prophylaxis.

  11. Automation for Crushing and Screening Equipment to Produce Graded Paving Crushed Stone

    Science.gov (United States)

    Tikhonov, Anatoly; Velichkin, Vladimir

    2017-10-01

    This paper offers analysis of factors related to production and storage of graded crushed stone, which adversely impact the service life and wear resistance of asphalt-concrete motor road pavements. The paper describes external and technology-related parameters that may cause changes of the preset ratio in graded crushed stone. Control factors are described that ensure the formulated fraction ratio in crushed stone by controlling the operation mode of the crushing and screening equipment. The paper also contains an ACS flow chart for crushing and screening equipment engaged in continuous closed-cycle two-stage technology. Performance of the ACS to maintain the preset fractionated crushed stone ratio has been confirmed with a mathematical model.

  12. Intraperitoneal stone migration during percutaneos nephrolithotomy

    Directory of Open Access Journals (Sweden)

    Akif Diri

    2014-12-01

    Full Text Available Percutaneos nephrolithotomy (PNL is the standard care for renal stones larger than 2 cm. The procedure has some major and minor complications. Renal pelvis laceration and stone migration to the retroperitoneum is one of the rare condition. We report the first case of intraperitoneal stone migration during PNL.

  13. Stone stability under non-uniform flow

    NARCIS (Netherlands)

    Hoan, N.T.

    2008-01-01

    Despite the fact that many studies on the stability of stones in bed protections under flowing water have been conducted, our knowledge is still far from advanced and reliable. Issues like how to quantify the hydraulic loads exerted on the stones on a bed and the associated stability of the stones

  14. Evolution of stone management in Australia.

    Science.gov (United States)

    Lee, Ming-Chak; Bariol, Simon Virgil

    2011-11-01

    What's known on the subject? and What does the study add? There is very little contemporary data regarding stone management in Australia. This study assesses the impact of technological advances on stone management practises, and raises questions as to why there is an increasing rate of intervention for stone disease in Australia. Knowledge of management trends as demonstrated in this paper give individual surgeons a guideline for contemporary practise in this country. • To examine trends in the operative management of upper urinary tract stone disease in Australia over the past 15 years. • The Medicare Australia and Australian Institute of Health and Welfare databases were used to determine the annual number of renal colic presentations and procedural interventions undertaken for stone disease. • In Australia over the past 15 years, the annual number of procedural interventions for upper urinary tract stones has increased, primarily due to the rising number of endoscopic procedures performed. • During this period, shock wave lithotripsy numbers have remained steady whilst open and percutaneous procedures have been in decline. • The introduction of and subsequent preference for less invasive techniques has changed the management pathway of patients presenting with stone disease in Australia. • Further studies are necessary to determine whether this escalation in endoscopic procedures is due to an increase in the incidence of stone disease, earlier detection, a lower intervention threshold or a higher retreatment rate. © 2011 THE AUTHORS. BJU INTERNATIONAL © 2011 BJU INTERNATIONAL.

  15. Thermoluminescence of pyramid stones

    International Nuclear Information System (INIS)

    Gomaa, M.A.; Eid, A.M.

    1982-01-01

    It is the aim of the present study to investigate some thermoluminescence properties of pyramid stones. Using a few grammes of pyramid stones from Pyramids I and II, the TL glow peaks were observed at 250 and 310 0 C, respectively. The TL glow peaks of samples annealed at 600 0 C, then exposed to 60 Co γ-rays were observed at 120, 190 and 310 0 C, respectively. The accumulated dose of natural samples is estimated to be around 310 Gray (31 krad). By assuming an annual dose is 1 mGy, the estimated age of pyramid stones is 0.31 M year. (author)

  16. Thermoluminescence of pyramid stones

    Energy Technology Data Exchange (ETDEWEB)

    Gomaa, M A; Eid, A M [Atomic Energy Establishment, Cairo (Egypt)

    1982-01-01

    It is the aim of the present study to investigate some thermoluminescence properties of pyramid stones. Using a few grammes of pyramid stones from Pyramids I and II, the TL glow peaks were observed at 250 and 310/sup 0/C, respectively. The TL glow peaks of samples annealed at 600/sup 0/C, then exposed to /sup 60/Co ..gamma..-rays were observed at 120, 190 and 310/sup 0/C, respectively. The accumulated dose of natural samples is estimated to be around 310 Gray (31 krad). By assuming an annual dose is 1 mGy, the estimated age of pyramid stones is 0.31 M year.

  17. Algorithm for definition of stones components at kidney-stones illness using two-energetic digital roentgen-graphic method

    International Nuclear Information System (INIS)

    Nedavnij, O.I.; Osipov, S.P.

    2001-01-01

    Paper presents the algorithm for definition of stone composition in case of kidney-stones using two-energy digital X-ray photography. One calculated the values of p information parameter for the main types of stones within 40-150 keV energy range. It was shown that p parameter dependence on energy was not essential one (maximum 3.5% deviation), p value for various chemical compositions of kidney stones ranged from 15% (calcium phosphate and calcium oxalate) up to 70% (calcium lactate and calcium oxalate). The conducted studies enable to make a conclusion about the possibility to define material representing the heart of kidney stones using two-energy digital X-ray photography. Paper includes recommendations on selection of the optimal energy values [ru

  18. Influence of Pelvicaliceal Anatomy on Stone Clearance After Flexible Ureteroscopy and Holmium Laser Lithotripsy for Large Renal Stones.

    Science.gov (United States)

    Inoue, Takaaki; Murota, Takashi; Okada, Shinsuke; Hamamoto, Shuzo; Muguruma, Kouei; Kinoshita, Hidefumi; Matsuda, Tadashi

    2015-09-01

    This study was performed to evaluate the impact of pelvicaliceal anatomy on stone clearance in patients with remnant fragments in the lower pole after flexible ureteroscopy and holmium laser lithotripsy (fURSL) for renal stones >15 mm. This retrospective study included 67 patients with radiopaque residual fragments (>2 mm) in the lower pole after fURSL for large renal stones (>15 mm). The preoperative infundibular length (IL), infundibular width (IW), infundibulopelvic angle (IPA), and caliceal pelvic height (CPH) were measured using intravenous urography. Multivariate analysis was performed to determine whether any of these measurements affected stone clearance. Of the 67 patients, 55 (82.1%) were stone free (SF) 3 months after fURSL. The anatomic factors significantly favorable for an SF status were a short IL, broad IW, wide IPA, and low CPH. On multivariate analysis, the IPA had a significant influence on an SF status after fURSL (p=0.010). An IPA renal stones according to our multivariate analysis. Additional studies are required to further evaluate the characteristics of the pelvicaliceal anatomy influencing stone clearance.

  19. A Boy with a Large Bladder Stone

    Directory of Open Access Journals (Sweden)

    Kuo-Shen Chow

    2008-08-01

    Full Text Available Despite the frequent association of urinary tract infection with vesicoureteral reflux and urinary calculi, since vesicouretal reflux is induced by bladder stones, the coexistence of vesicoureteral reflux and bladder stones is rare. Because of its occurrence in children belonging to poor socioeconomic groups, it is believed to be a deficiency disorder. Most cases of bladder stones occur between the ages of 2 and 5 years. Common clinical presentations of bladder stones include urinary dribbling and enuresis, frequency of micturition, pain during micturition, pelvic pain and hematuria. We report the occurrence of a large bladder stone in a boy, who experienced intermittent lower abdominal pain and urinary incontinence, both during the day and at night. He had been diagnosed with enuresis and treated in pediatric clinics for 1 year. Delayed diagnosis resulted in bladder stone formation. The stone was larger than 2.5 cm and open vesicolithotomy was therefore selected as the best and safest treatment choice. His symptoms disappeared after surgery. Thorough metabolic and environmental evaluations of such cases are required on an individual basis. Bladder stones should be considered as a possible diagnosis in children presenting with urinary incontinence.

  20. Percutaneous nephrolithotomy for the treatment of radiolucent renal stones in children: is it different opaque stone treatment?

    Science.gov (United States)

    Adanur, Şenol; Ziypak, Tevfik; Sancaktutar, Ahmet Ali; Tepeler, Abdülkadir; Reşorlu, Berkan; Söylemez, Haluk; Dağgülli, Mansur; Özbey, İsa; Unsal, Ali

    2014-02-01

    We aimed to evaluate the effectiveness of percutaneous nephrolithotomy (PNL), stone-free rates, and related complications in children with radiolucent renal stones. A total of 56 patients aged auxillary treatment method was detected as 94.6%. The total complication rate was 19.6% (11 patients). No adjacent organ injury was observed. All of the complications that occurred were minor according to the Clavien classification (Clavien Grades I-II). PNL can be applied to radiolucent pediatric renal stones in children with similar success, and complication rates as noted for radiopaque stones.

  1. Female stone disease: the changing trend.

    Science.gov (United States)

    Marickar, Y M Fazil; Vijay, Adarsh

    2009-12-01

    This paper has attempted to assess the changes noted in the trends in the incidence and biochemical pattern of female urolithiasis patients during the period 1971-2008. A prospective descriptive clinical study was done on 8,590 stone patients belonging to both sexes treated at the urinary stone clinic. The incidence of stone disease among the two sexes was plotted. The various metabolic parameters including 24-h urine volume, urine calcium, phosphorus, uric acid, oxalate, magnesium, creatinine and citrate, serum creatinine, calcium, phosphorus, uric acid and magnesium and calculated parameter calcium:magnesium ratio were studied. The possible causes for the change in incidence of stone disease in the female sex were elucidated. Of the patients studied, 12.7% (1,091) were females. There was a definite increase in the incidence of female urolithiasis over the past 37 years (P stone genesis, together with the increased excretion of calcium and oxalate may have contributed to the increasing incidence of stone disease in females. This might be due to changes in living standards and dietary habits.

  2. Size matters. The width and location of a ureteral stone accurately predict the chance of spontaneous passage

    Energy Technology Data Exchange (ETDEWEB)

    Jendeberg, Johan; Geijer, Haakan; Alshamari, Muhammed; Liden, Mats [Oerebro University Hospital, Department of Radiology, Faculty of Medicine and Health, Oerebro (Sweden); Cierzniak, Bartosz [Oerebro University, Department of Surgery, Faculty of Medicine and Health, Oerebro (Sweden)

    2017-11-15

    To determine how to most accurately predict the chance of spontaneous passage of a ureteral stone using information in the diagnostic non-enhanced computed tomography (NECT) and to create predictive models with smaller stone size intervals than previously possible. Retrospectively 392 consecutive patients with ureteric stone on NECT were included. Three radiologists independently measured the stone size. Stone location, side, hydronephrosis, CRP, medical expulsion therapy (MET) and all follow-up radiology until stone expulsion or 26 weeks were recorded. Logistic regressions were performed with spontaneous stone passage in 4 weeks and 20 weeks as the dependent variable. The spontaneous passage rate in 20 weeks was 312 out of 392 stones, 98% in 0-2 mm, 98% in 3 mm, 81% in 4 mm, 65% in 5 mm, 33% in 6 mm and 9% in ≥6.5 mm wide stones. The stone size and location predicted spontaneous ureteric stone passage. The side and the grade of hydronephrosis only predicted stone passage in specific subgroups. Spontaneous passage of a ureteral stone can be predicted with high accuracy with the information available in the NECT. We present a prediction method based on stone size and location. (orig.)

  3. Pattern of family history in stone patients.

    Science.gov (United States)

    Marickar, Y M Fazil; Salim, Abiya; Vijay, Adarsh

    2009-12-01

    Genetic predisposition to urolithiasis is a much discussed topic. The objective of this paper is to identify the types of family members of proved urinary stone patients, who have a history of urinary stone formation. The study population consisted of 2,157 urinary stone patients interviewed in 2003-2007 in the urinary stone clinic. Family members with stone history were classified as group 1--first order single (one person in the immediate family-father, mother, siblings, or children), group 2--first order multiple (more than one member in the above group), group 3--second order single (one person in the blood relatives in family--grandparents, grandchildren, uncles, aunts, cousins, etc.) and group 4--second order multiple (more than one member in the above group). Of the 2,157 patients studied, 349 patients gave positive history of stone disease constituting 16.18%. Of these, 321 were males and 28 were females. Subdivision of the family members showed that 282 patients (80.80%) had single family member with stones and the rest 67 (19.20%) had multiple family members with history of stone disease. Group 1 which constituted one family member in the immediate family had 255 involvements (father: 88, mother: 16, brother: 135, sister: 2, son: 10, and daughter: 4); Group 2 with multiple members in the immediate family constituted 51 relatives; of these, father and brother combination was the most common with 35 occurrences. Group 3 with one person in the distant relatives in family namely grandparents, grand children, uncles, aunts, cousins, etc. constituted 27 occurrences and Group 4 with more than one member in the distant family constituted 16 occurrences. It is concluded that single family member involvement was more than multiple involvements. Males predominated. Stone occurrence was more in the immediate family members than distant relatives. Brothers formed the most common group to be involved with stone disease. Study of stone risk in the family members should

  4. Lioz: The Stone that made Lisbon reborn - A Global Heritage Stone Resource Proposal

    Science.gov (United States)

    Lopes, Luis

    2017-04-01

    Lioz: The Stone that made Lisbon reborn - A Global Heritage Stone Resource Proposal Explored since the Roman Period, the Lioz (Cenomanian age microcrystalline fossiliferous limestone) is the main stone used in the buildings and monuments of Lisbon. After the great cataclysm of 1755 (earthquake, tsunami and fire) of 1755, the already known great quality and the near occurrence of these limestones were wisely used in the great reconstruction of the "Capital do Império" (Capital of the Empire). At the time, Lisbon was one of the largest European cities and great business center of the World, so the necessary and urgent reconstruction was not so difficult to start. Sebastião José de Carvalho e Melo, better known as "Marquês de Pombal", Secretary of King José I, successfully took up the challenge of rebuilding Lisbon. Inside the actual Portuguese capital geographical limits, several quarries of the Cretaceous limestone were explored; some still exist and are classified as geomonuments (i.e., Rio Seco Geomonument, 38 ° 42'21 .67''N; 9 ° 11 '30.37''W). As the City boundaries expanded, the quarries stopped and now there is no one asset in Lisbon. The most important exploitation and processing Lioz stone center was situated in Pêro Pinheiro, 20 km NW of Lisbon. Most of the stones used in the National Palace-Convent of Mafra (1717) belongs to the four main types of Lioz (the cream/white "Abancado", the pink/dark pink "Encarnadão", the yellow "Amarelo de Negrais" and the blueish grey "Azulino"), either cut "against" (perpendicular to the bedding plane) or "along" (parallel to the bedding plane). The orientation stone cut deeply controls texture and mechanical properties of the rocks that behaves as different ones were considered. In the last two decades, the Lioz extraction was almost extinguished. However, some of the old quarries was reactivated and produces first quality blocks needed both for new works and restoration of historic buildings and monuments. The

  5. Achtergronden bij de berekening van vermesting van bodem en grondwater voor de 5e Milieuverkenning met het model STONE

    NARCIS (Netherlands)

    Overbeek GBJ; Grinsven JJM; Roelsma J; Groenendijk P; Egmond PM van; Beusen AHW; LBG; LAE; CIM

    2001-01-01

    Ten behoeve van de vijfde milieuverkenning is de voorgenomen Integrale Aanpak van de Mestproblematiek van de Nederlandse regering doorgerekend met het model STONE naar landsdekkende milieueffecten op bodem, bovenste grondwater en belasting van het regionale oppervlaktewater voor de periode

  6. Pathological and therapeutic significance of cellular invasion by Proteus mirabilis in an enterocystoplasty infection stone model

    NARCIS (Netherlands)

    R.B. Mathoera (Rejiv); D.J. Kok (Dirk); C.M. Verduin (Cees); R.J.M. Nijman (Rien)

    2002-01-01

    textabstractProteus mirabilis infection often leads to stone formation. We evaluated how bacterium-mucin adhesion, invasion, and intracellular crystal formation are related to antibiotic sensitivity and may cause frequent stone formation in enterocystoplasties. Five intestinal

  7. “Die Another Day”: A Qualitative Analysis of Hmong Experiences with Kidney Stones

    Directory of Open Access Journals (Sweden)

    Kathleen A. Culhane-Pera

    2007-01-01

    Full Text Available Background: A chart review at a urological office revealed that Hmong patients present with higher rates of kidney stones, uric acid stones, and complications from kidney stones than non-Hmong patients. In order to ultimately redress this health disparity, a conferenceof Hmong and non-Hmong health care providers decided that we needed to first understand the pertinent social, cultural, economic, and biological factors contributing to the disparity. This research project sought to elicit Hmong patients and family members’explanatory models, decision-making processes, and experiences with the health care system.Methods: We conducted in–depth interviews with 10 Hmong kidney stone patients, 11 family members of 9 patients, and 4 traditional healers. All 10 patients had received urological interventions, including ureteroscopy (8, percutaneous lithotomy (5 and nephrectomy (2. Some patients had postponed medical assistance (6 and had refusedprocedures (4. We qualitatively analyzed the transcribed and translated interviews with an Excel spread sheet and N6 computer software. Results were discussed with patients and a community advisory council.Results: Hmong concepts of kidney function and explanatory models of kidney stones are a blend of traditional and biomedical concepts. Kidney stones are understood as acute health problems caused by hard substances in water and food that stick to the kidney, which weak kidneys cannot excrete. Kidney stone sufferers do not know they have stones until they pass a stone or they see stones on X-rays, as pain or hematuria are non-specific symptoms. They prefer medications, including herbal medicines, to invasive urologicalprocedures. In making decisions about urological interventions, Hmong patients balance fear of disease (pain and renal failure with fear of doctors (complications from interventions and anesthesia. While patients have variable balance points to accept interventions, the basic philosophy of

  8. The twelve colourful stones

    International Nuclear Information System (INIS)

    Doria, R.M.

    1983-01-01

    A dynamics with twelve colourful stones is created based on the concepts of gauge and colour. It is associated different gauge fields to the same group. A group of gauge invariant Lagrangians is established. A gauge invariant mass term is introduced. The colourful stones physical insight is to be building blocks for quarks and leptons. (Author) [pt

  9. [Relational database for urinary stone ambulatory consultation. Assessment of initial outcomes].

    Science.gov (United States)

    Sáenz Medina, J; Páez Borda, A; Crespo Martinez, L; Gómez Dos Santos, V; Barrado, C; Durán Poveda, M

    2010-05-01

    To create a relational database for monitoring lithiasic patients. We describe the architectural details and the initial results of the statistical analysis. Microsoft Access 2002 was used as template. Four different tables were constructed to gather demographic data (table 1), clinical and laboratory findings (table 2), stone features (table 3) and therapeutic approach (table 4). For a reliability analysis of the database the number of correctly stored data was gathered. To evaluate the performance of the database, a prospective analysis was conducted, from May 2004 to August 2009, on 171 stone free patients after treatment (EWSL, surgery or medical) from a total of 511 patients stored in the database. Lithiasic status (stone free or stone relapse) was used as primary end point, while demographic factors (age, gender), lithiasic history, upper urinary tract alterations and characteristics of the stone (side, location, composition and size) were considered as predictive factors. An univariate analysis was conducted initially by chi square test and supplemented by Kaplan Meier estimates for time to stone recurrence. A multiple Cox proportional hazards regression model was generated to jointly assess the prognostic value of the demographic factors and the predictive value of stones characteristics. For the reliability analysis 22,084 data were available corresponding to 702 consultations on 511 patients. Analysis of data showed a recurrence rate of 85.4% (146/171, median time to recurrence 608 days, range 70-1758). In the univariate and multivariate analysis, none of the factors under consideration had a significant effect on recurrence rate (p=ns). The relational database is useful for monitoring patients with urolithiasis. It allows easy control and update, as well as data storage for later use. The analysis conducted for its evaluation showed no influence of demographic factors and stone features on stone recurrence.

  10. Extracorporeal shock-wave lithotripsy of bile duct stones

    International Nuclear Information System (INIS)

    Lee, Jong Tae; Kim, Myung Joon; Yoo, Hyung Sik; Suh, Jung Ho; Lee, Moo Sang; Jo, Jang Hwan; Kim, Byung Ro

    1989-01-01

    During the past one and half year, we performed ESWL therapy in 13 patients with common bile duct and intrahepatic duct stones, applying Lithostar-R (Siemens co. West Germany) and analyzed their results. In 13 patients, 9 residual common bile duct stones and 7 intrahepatic duct stones were selected postoperatively. The size of stones were ranged from 0.7 cm to 3.5 cm in diameter. 2 stones were multiple and the remained 14 were single in number. The visualization of stones were done with fluoroscopy after the injection of contrast media via cholangiographic T-tube or ERCP. ESWL were applied continuously until stone disintegration was visible, or upto maximum number of 3500 discharge of shock wave. If not disintegrated upto 3500, patients were underwent second or third lithotripsy session with interval of one week. Our results showed that among 9 common bile duct stones, 4 were completely disintegrated and passed out spontaneously, but 3 partially fragmented and removed by the additional procedure. 2 were failed. Among 7 intrahepatic stones, 3 completely and 2 partially were succeeded. One stone partially fragmented were retained without removal and other one were failed. Skin petechia in all patients were revealed on the entry port of shock wave, but no serous complication was not occurred

  11. Extracorporeal shock-wave lithotripsy of bile duct stones

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Tae; Kim, Myung Joon; Yoo, Hyung Sik; Suh, Jung Ho; Lee, Moo Sang; Jo, Jang Hwan; Kim, Byung Ro [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1989-12-15

    During the past one and half year, we performed ESWL therapy in 13 patients with common bile duct and intrahepatic duct stones, applying Lithostar-R (Siemens co. West Germany) and analyzed their results. In 13 patients, 9 residual common bile duct stones and 7 intrahepatic duct stones were selected postoperatively. The size of stones were ranged from 0.7 cm to 3.5 cm in diameter. 2 stones were multiple and the remained 14 were single in number. The visualization of stones were done with fluoroscopy after the injection of contrast media via cholangiographic T-tube or ERCP. ESWL were applied continuously until stone disintegration was visible, or upto maximum number of 3500 discharge of shock wave. If not disintegrated upto 3500, patients were underwent second or third lithotripsy session with interval of one week. Our results showed that among 9 common bile duct stones, 4 were completely disintegrated and passed out spontaneously, but 3 partially fragmented and removed by the additional procedure. 2 were failed. Among 7 intrahepatic stones, 3 completely and 2 partially were succeeded. One stone partially fragmented were retained without removal and other one were failed. Skin petechia in all patients were revealed on the entry port of shock wave, but no serous complication was not occurred.

  12. Building stones can be of geoheritage significance

    Science.gov (United States)

    Brocx, Margaret; Semeniuk, Vic

    2017-04-01

    Building stones have generally been assigned values according to their cultural, aesthetic, and rarity significance, amongst other criteria, but they also may have geoheritage significance. This is akin to the geoheritage significance ascribed to minerals and fossils housed as ex situ specimens in museums. We proffer the notion that building stones can be of geoheritage value particularly where they comprise permanent buildings, they illustrate significant windows into the history of the Earth, and they can be visited as an ex situ museum locality (e.g., the "Blue Granite" of Iceland) for education as part of building-stone tours. For some rocks the quarries that supplied the building stone are no longer in existence and hence the building stones provide the only record of that type of material; for other rocks, the building stone may illustrate features in the lithology no longer present in the quarry itself (e.g., rare and large xenoliths). Building stones are particularly significant as they are often polished and manifest structures, fabrics, and textures not evident in outcrop. We illustrate here examples of building stone of geoheritage significance using Australian and International examples. Australian designated stones could include the "Sydney Sandstone" or "Victorian Bluestone". For international examples, there is the famous "Carrara Marble" in Italy and the widely known "Portland Limestone" from southern England, the latter having been utilized for St Pauls Cathedral in London and the UN building in New York City.

  13. Achtergronden bij de berekening van vermesting van bodem en grondwater voor de 5e milieuverkenning met het model STONE

    NARCIS (Netherlands)

    Overbeek, G.B.J.; Grinsven, van J.J.M.; Roelsma, J.; Groenendijk, P.; Egmond, van P.M.; Beusen, A.H.W.

    2001-01-01

    Ten behoeve van de vijfde milieuverkenning is de voorgenoomen Integrale Aanpak van de mestproblematiek van de Nederlandse regering doorgerekend met het model STONE. Er is gekeken naar landsdekkende milieueffecten op bodemm, bovenste grondwater en belasting van het regionale oppervlaktewater vor de

  14. Numerical Modelling of Connections Between Stones in Foundations of Historical Buildings

    Science.gov (United States)

    Przewlocki, Jaroslaw; Zielinska, Monika; Grebowski, Karol

    2017-12-01

    The aim of this paper is to analyse the behaviour of old building foundations composed of stones (the main load-bearing elements) and mortar, based on numerical analysis. Some basic aspects of historical foundations are briefly discussed, with an emphasis on their development, techniques, and material. The behaviour of a foundation subjected to the loads transmitted from the upper parts of the structure is described using the finite element method (FEM). The main problems in analysing the foundations of historical buildings are determining the characteristics of the materials and the degree of degradation of the mortar, which is the weakest part of the foundation. Mortar is graded using the damaged-plastic model. In this model, exceeding the bearing capacity occurs due to the degradation of materials. The damaged-plastic model is the most accurate model describing the work and properties of mortar because it shows exactly what happens with this material throughout its total load history. For a uniformly loaded fragment of the foundation, both stresses and strains were analysed. The results of the analysis presented in this paper contribute to further research in the field of understanding both behaviour and modelling in historical buildings’ foundations.

  15. Tamsulosin and spontaneous passage of ureteral stones in children: a multi-institutional cohort study.

    Science.gov (United States)

    Tasian, Gregory E; Cost, Nicholas G; Granberg, Candace F; Pulido, Jose E; Rivera, Marcelino; Schwen, Zeyad; Schulte, Marion; Fox, Janelle A

    2014-08-01

    Tamsulosin is associated with increased passage of ureteral stones in adults but its effectiveness in children is uncertain. We determined the association between tamsulosin and the spontaneous passage of ureteral stones in children. We performed a multi-institutional retrospective cohort study of patients 18 years or younger who presented between 2007 and 2012 with ureteral stones up to 10 mm and who were treated with tamsulosin or oral analgesics alone. The outcome was spontaneous stone passage, defined as radiographic clearance and/or patient report of passage. Subjects prescribed tamsulosin were matched with subjects prescribed analgesics alone, using nearest neighbor propensity score matching to adjust for treatment selection. Conditional logistic regression models were used to estimate the association between tamsulosin and spontaneous passage of ureteral stones, adjusting for stone size and location. Of 449 children with ureteral stones 334 were eligible for inclusion, and complete data were available for 274 patients from 4 institutions (99 receiving tamsulosin, 175 receiving analgesics alone). Following case matching, there were no differences in age, gender, weight, height, stone size or stone location between the 99 subjects prescribed tamsulosin and the 99 propensity score matched subjects prescribed analgesics alone. In the tamsulosin cohort 55% of ureteral stones passed, compared to 44% in the analgesics alone cohort (p=0.03). In multivariate analysis adjusting for stone size and location tamsulosin was associated with spontaneous passage of ureteral stones (OR 3.31, 95% CI 1.49-7.34). The odds of spontaneous passage of ureteral stones were greater in children prescribed tamsulosin vs analgesics alone. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  16. Piezoelectric extracorporeal lithotripsy of gallbladder stones: New inclusion criteria

    Energy Technology Data Exchange (ETDEWEB)

    Han, Joon Koo; Choi, Byung Ihn; Shin, Yong Moon; Yoon, Yong Kyu; Yoon, Yong Bum; Park, Yong Hyun; Kim, Chu Wan; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1994-08-15

    To establish the optimal inclusion criteria for the patients with gallbladder stones to extracorporeal shock wave lithotripsy(ESWL) by retrospectively analyzed our current results. Data obtained from 201 patients with gallbladder stones treated with ESWL and oral chemolytic agent from November 1988 to July 1992 were retrospectively analyzed. Ninety-six had radiolucent stones and 105 had radiopaque stones. We used piezoelectric lithotriptor(EDAP LT. 01) and there were no limitation in number of sessions or total number of shock waves. ESWL was repeated until the size of the largest fragment is smaller than 4 mm. Follow up ultrasound was done in every three months after the successful fragmentation. Average length of the follow up was 205 days. We analyzed the rate of successful fragmentation, number of shock waves needed to achieve successful fragmentation according to the size, number of stones as well as the presence of the calcification. Stone-free rate after 6 months was also calculated from all subgroups and compared to each other. The rate of successful fragmentation was 76.2% for radiolucent stones and 65.6% for radiopaque stones(p> 0.05) after 46,731 and 56,111 shock wave respectively(p > 0.05) The rate of successful fragmentation was highest in patients with single, radiolucent stone smaller than 2 cm(91.7%) followed by single radiolucent stone larger than 2 cm(83.3%), multiple calcified stones smaller than 2 cm (77.4%) and single calcified stone smaller than 2 cm(72.1%). The rate of complete stone clearance after 6 month follow-up was highest in patients with single radiolucent stone smaller than 2 cm (63.3%) and followed by multiple calcified stones smaller than 2 cm(37.3%), single calcified stone smaller than 2 cm(33.9%)(p < 0.05). To obtain better results with ESWL in patients with gallbladder stone, the authors propose a more strict inclusion criteria, which is the patient with a single, radiolucent stone smaller than 2 cm.

  17. Piezoelectric extracorporeal lithotripsy of gallbladder stones: New inclusion criteria

    International Nuclear Information System (INIS)

    Han, Joon Koo; Choi, Byung Ihn; Shin, Yong Moon; Yoon, Yong Kyu; Yoon, Yong Bum; Park, Yong Hyun; Kim, Chu Wan; Han, Man Chung

    1994-01-01

    To establish the optimal inclusion criteria for the patients with gallbladder stones to extracorporeal shock wave lithotripsy(ESWL) by retrospectively analyzed our current results. Data obtained from 201 patients with gallbladder stones treated with ESWL and oral chemolytic agent from November 1988 to July 1992 were retrospectively analyzed. Ninety-six had radiolucent stones and 105 had radiopaque stones. We used piezoelectric lithotriptor(EDAP LT. 01) and there were no limitation in number of sessions or total number of shock waves. ESWL was repeated until the size of the largest fragment is smaller than 4 mm. Follow up ultrasound was done in every three months after the successful fragmentation. Average length of the follow up was 205 days. We analyzed the rate of successful fragmentation, number of shock waves needed to achieve successful fragmentation according to the size, number of stones as well as the presence of the calcification. Stone-free rate after 6 months was also calculated from all subgroups and compared to each other. The rate of successful fragmentation was 76.2% for radiolucent stones and 65.6% for radiopaque stones(p> 0.05) after 46,731 and 56,111 shock wave respectively(p > 0.05) The rate of successful fragmentation was highest in patients with single, radiolucent stone smaller than 2 cm(91.7%) followed by single radiolucent stone larger than 2 cm(83.3%), multiple calcified stones smaller than 2 cm (77.4%) and single calcified stone smaller than 2 cm(72.1%). The rate of complete stone clearance after 6 month follow-up was highest in patients with single radiolucent stone smaller than 2 cm (63.3%) and followed by multiple calcified stones smaller than 2 cm(37.3%), single calcified stone smaller than 2 cm(33.9%)(p < 0.05). To obtain better results with ESWL in patients with gallbladder stone, the authors propose a more strict inclusion criteria, which is the patient with a single, radiolucent stone smaller than 2 cm

  18. Stepping Stones Triple P-Positive Parenting Program for children with disability: a systematic review and meta-analysis.

    Science.gov (United States)

    Tellegen, Cassandra L; Sanders, Matthew R

    2013-05-01

    This systematic review and meta-analysis evaluated the treatment effects of a behavioral family intervention, Stepping Stones Triple P (SSTP) for parents of children with disabilities. SSTP is a system of five intervention levels of increasing intensity and narrowing population reach. Twelve studies, including a total of 659 families, met eligibility criteria. Studies needed to have evaluated SSTP, be written in English or German, contribute original data, and have sufficient data for analyses. No restrictions were placed on study design. A series of meta-analyses were performed for seven different outcome categories. Analyses were conducted on the combination of all four levels of SSTP for which evidence exists (Levels 2-5), and were also conducted separately for each level of SSTP. Significant moderate effect sizes were found for all levels of SSTP for reducing child problems, the primary outcome of interest. On secondary outcomes, significant overall effect sizes were found for parenting styles, parenting satisfaction and efficacy, parental adjustment, parental relationship, and observed child behaviors. No significant treatment effects were found for observed parenting behaviors. Moderator analyses showed no significant differences in effect sizes across the levels of SSTP intervention, with the exception of child observations. Risk of bias within and across studies was assessed. Analyses suggested that publication bias and selective reporting bias were not likely to have heavily influenced the findings. The overall evidence base supported the effectiveness of SSTP as an intervention for improving child and parent outcomes in families of children with disabilities. Limitations and future research directions are discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Using a three-dimensional computer assisted stone volume estimates to evaluate extracorporeal shockwave lithotripsy treatment of kidney stones

    DEFF Research Database (Denmark)

    Bigum, Lene Hyldgaard; Ulriksen, Peter Sommer; Omar, Omar Salah

    2016-01-01

    Hospital between April 2013 and January 2014 and follow-up was possible in 77 (95 %) patients. NCCT was used before and after treatment. Treatment response was expressed as a reduction of the stone volume. Stone characteristics as the stone volumes, HU, SSD and localization were measured by radiologist...

  20. Predictions of outcomes of renal stones after extracorporeal shock wave lithotripsy from stone characteristics determined by unenhanced helical computed tomography: a multivariate analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Li-Jen; Wong, Yon-Cheong [Chang Gung University, Department of Diagnostic Radiology, Chang Gung Memorial Hospital, Taipei (Taiwan); Chuang, Cheng-Keng; Chu, Sheng-Hsien; Chen, Chih-Shou; Chiang, Yang-Jen [Chang Gung University, Department of Urology, Chang Gung Memorial Hospital, Taipei (Taiwan); See, Lai-Chu [Chang Gung University, Department of Biostatistics Center, Chang Gung Memorial Hospital, Taipei (Taiwan)

    2005-11-01

    The aim of our study is to analyze the relationships between the characteristics of renal stones determined by unenhanced helical computed tomography (UHCT) and their outcomes after extracorporeal shock wave lithotripsy (ESWL) as well as to predict ESWL outcomes of renal stones by their UHCT characteristics with the use of multivariate analysis. During a 7-month period, 80 adult patients with renal stones underwent ESWL as well as UHCT both before and 3 months after ESWL. Of the 80 patients, 42 patients were classified as ESWL successes and 38 as ESWL failures based on their post-ESWL UHCT findings. For pre-ESWL UHCT, a stone number of more than 2 (P=0.0236), a maximal stone size of greater than 12 mm (P<0.0001), a stone burden of more than 700 mm{sup 3} (P<0.0001), a maximal stone density of more than 900 HU (P=0.0008) and nonround/oval stones (P=0.0007) were associated with ESWL failure outcomes. Multivariate analysis demonstrated that a stone burden of more than 700 mm{sup 3} (P=0.0003), the presence of nonround/oval stones (P=0.0072) and a maximal stone density of more than 900 HU (P=0.0430) were statistically significant predictors of a failure outcome for ESWL. Thus, the analysis of stone characteristics of renal stones by UHCT is helpful in selecting appropriate patients undergoing ESWL for favorable outcomes and reduces the overall costs of the treatment of renal stones. (orig.)

  1. Cover stones on liquefiable soil bed under waves

    DEFF Research Database (Denmark)

    Sumer, B. Mutlu; Hatipoglu, Figen; Fredsøe, Jørgen

    2010-01-01

    The paper describes the results of an experimental study on the behavior of cover stones on a liquefiable soil bed exposed to a progressive wave. The soil was silt with d50=0.098mm. Stones, the size of 4cm, were used as cover material. The effect of packing density of stones, and that of number...... of stone layers (including the effect of an intermediate filter layer) were investigated. Pore pressure was measured across the soil depth. The experiments show that the soil liquefaction depended mainly on two parameters: the packing density of stones, and the number of stone layers. When the liquefaction...

  2. Extracorporeal shock wave lithotripsy for urinary stones

    International Nuclear Information System (INIS)

    Shinn, Kyung Sub; Kim, Hyun; Byun, Jae Young; Lee, Myung Hee; Bahk, Yong Whee; Park, Yong Hyun

    1988-01-01

    Extracorporeal shock wave lithotripsy (ESWL) is a new noninvasive treatment modality for urinary stones, and it sometimes is to necessitate endourologic techniques. ESWL with an Edap lithotripter which uses piezo-electric elements, was performed in 142 cases (130 patients) with urinary stones including 68 in calices, 30 in pelves, and 44 in ureters. Technical factors were 100 storages at 5 to 10 pulse rates/sec and 70-100% adjustable power for about 60 minutes (15-90) for renal stones, and 200 storages at 20 pulse rates/sec and 100% adjustable power for about 60 minutes for ureteral stones in a single treatment under stone localization by 5 MHz ultrasonic sector scanner. All patients were treated at Kangnam St.Mary's Hospital of Catholic University Medical College during the 5 months period from May 1, 1987. Every patient had pre-treatment chest, plain abdomen, intravenous urogram and ultrasonogram studies and post-treatment follow-up abdominal radiograms in 1 to 3 months after ESWL.The overall success rate of ESWL in 142 cases was 94.4%. Eight out of 142 cases were successful. Thus, 134 cases were analysed. Of these, 58 cases (43.3%) received one treatment, 33 cases (24.6%) two treatments, 16 cases (11.9%) three treatments and 27 cases (20.2%) more than four treatments. Renal stones were more successfully treated (98.0%) than ureteral stones (88.1%), and calyceal stones presented the highest success rate (98.5%). The stones as small as 5 to 10 mm in size were easily fragmented and the stones of round of oval shape were more easily pulverized than those of staghorn or amorphous shape. The adjunctive endourlogic techniques such as percutaneous nephrostomy, ureteral catheterization or internal ureteral stenting with a double pigtail catheter were required in 17 cases (11.9%). Complications of ESWL for urolithiasis included hematuria (84.5%), flank pain (8.5%) and fever (5.6%), which were controlled without specific treatment. ESWL using ultrasonic localization was

  3. Extracorporeal shock wave lithotripsy for urinary stones

    Energy Technology Data Exchange (ETDEWEB)

    Shinn, Kyung Sub; Kim, Hyun; Byun, Jae Young; Lee, Myung Hee; Bahk, Yong Whee; Park, Yong Hyun [Kangnam St. Mary' s Hospital, Catholic University Medical College, Seoul (Korea, Republic of)

    1988-06-15

    Extracorporeal shock wave lithotripsy (ESWL) is a new noninvasive treatment modality for urinary stones, and it sometimes is to necessitate endourologic techniques. ESWL with an Edap lithotripter which uses piezo-electric elements, was performed in 142 cases (130 patients) with urinary stones including 68 in calices, 30 in pelves, and 44 in ureters. Technical factors were 100 storages at 5 to 10 pulse rates/sec and 70-100% adjustable power for about 60 minutes (15-90) for renal stones, and 200 storages at 20 pulse rates/sec and 100% adjustable power for about 60 minutes for ureteral stones in a single treatment under stone localization by 5 MHz ultrasonic sector scanner. All patients were treated at Kangnam St.Mary's Hospital of Catholic University Medical College during the 5 months period from May 1, 1987. Every patient had pre-treatment chest, plain abdomen, intravenous urogram and ultrasonogram studies and post-treatment follow-up abdominal radiograms in 1 to 3 months after ESWL.The overall success rate of ESWL in 142 cases was 94.4%. Eight out of 142 cases were successful. Thus, 134 cases were analysed. Of these, 58 cases (43.3%) received one treatment, 33 cases (24.6%) two treatments, 16 cases (11.9%) three treatments and 27 cases (20.2%) more than four treatments. Renal stones were more successfully treated (98.0%) than ureteral stones (88.1%), and calyceal stones presented the highest success rate (98.5%). The stones as small as 5 to 10 mm in size were easily fragmented and the stones of round of oval shape were more easily pulverized than those of staghorn or amorphous shape. The adjunctive endourlogic techniques such as percutaneous nephrostomy, ureteral catheterization or internal ureteral stenting with a double pigtail catheter were required in 17 cases (11.9%). Complications of ESWL for urolithiasis included hematuria (84.5%), flank pain (8.5%) and fever (5.6%), which were controlled without specific treatment. ESWL using ultrasonic localization

  4. Factors affecting lower calyceal stone clearance after Extracorporeal ...

    African Journals Online (AJOL)

    shanker

    have been identified [1,3]. These include stone characteristics, the type of lithotripter used, LPC anatomy and body habitus. For iso- lated LPC stones, the pelvicalyceal angle, infundibulum length and width are considered important determinants for stone clearance. The impact of body habitus on stone clearance has so far ...

  5. 78 FR 3911 - Big Stone National Wildlife Refuge, Big Stone and Lac Qui Parle Counties, MN; Final Comprehensive...

    Science.gov (United States)

    2013-01-17

    ... DEPARTMENT OF THE INTERIOR Fish and Wildlife Service [FWS-R3-R-2012-N259; FXRS1265030000-134-FF03R06000] Big Stone National Wildlife Refuge, Big Stone and Lac Qui Parle Counties, MN; Final Comprehensive... significant impact (FONSI) for the environmental assessment (EA) for Big Stone National Wildlife Refuge...

  6. Emergency management of ureteral stones: Recent advances

    Directory of Open Access Journals (Sweden)

    Luis Osorio

    2008-01-01

    Full Text Available Most ureteral stones can be observed with reasonable expectation of uneventful stone passage. When an active ureteral stone treatment is warranted, the best procedure to choose is dependent on several factors, besides stone size and location, including operators′ experience, patients′ preference, available equipment and related costs. Placement of double-J stent or nephrostomy tube represents the classical procedures performed in a renal colic due to acute ureteral obstruction when the conservative drug therapy does not resolve the symptoms. These maneuvers are usually followed by ureteroscopy or extracorporeal shockwave lithotripsy, which currently represent the mainstay of treatment for ureteral stones. In this review paper a literature search was performed to identify reports dealing with emergency management of renal colic due to ureteral stones. The main aspects related to this debated issue are analyzed and the advantages and disadvantages of each treatment option are carefully discussed.

  7. Emergency management of ureteral stones: Recent advances.

    Science.gov (United States)

    Osorio, Luis; Lima, Estêvão; Autorino, Riccardo; Marcelo, Filinto

    2008-10-01

    Most ureteral stones can be observed with reasonable expectation of uneventful stone passage. When an active ureteral stone treatment is warranted, the best procedure to choose is dependent on several factors, besides stone size and location, including operators' experience, patients' preference, available equipment and related costs. Placement of double-J stent or nephrostomy tube represents the classical procedures performed in a renal colic due to acute ureteral obstruction when the conservative drug therapy does not resolve the symptoms. These maneuvers are usually followed by ureteroscopy or extracorporeal shockwave lithotripsy, which currently represent the mainstay of treatment for ureteral stones. In this review paper a literature search was performed to identify reports dealing with emergency management of renal colic due to ureteral stones. The main aspects related to this debated issue are analyzed and the advantages and disadvantages of each treatment option are carefully discussed.

  8. Bladder stones after bladder augmentation are not what they seem.

    Science.gov (United States)

    Szymanski, Konrad M; Misseri, Rosalia; Whittam, Benjamin; Lingeman, James E; Amstutz, Sable; Ring, Joshua D; Kaefer, Martin; Rink, Richard C; Cain, Mark P

    2016-04-01

    Bladder and renal calculi after bladder augmentation are thought to be primarily infectious, yet few studies have reported stone composition. The primary aim was to assess bladder stone composition after augmentation, and renal stone composition in those with subsequent nephrolithiasis. The exploratory secondary aim was to screen for possible risk factors for developing infectious stones. Patients treated for bladder stones after bladder augmentation at the present institution between 1981 and 2012 were retrospectively reviewed. Data were collected on demographics, surgeries and stone composition. Patients without stone analysis were excluded. Stones containing struvite, carbonate apatite or ammonium acid ureate were classified as infectious. The following variables were analyzed for a possible association with infectious bladder stone composition: gender, history of cloacal exstrophy, ambulatory status, nephrolithiasis, recurrent urea-splitting urinary tract infections, first vs recurrent stones, timing of presentation with a calculus, history of bladder neck procedures, catheterizable channel and vesicoureteral reflux. Fisher's exact test was used for analysis. Of the 107 patients with bladder stones after bladder augmentation, 85 met inclusion criteria. Median age at augmentation was 8.0 years (follow-up 10.8 years). Forty-four patients (51.8%) recurred (14 multiple recurrences, 143 bladder stones). Renal calculi developed in 19 (22.4%) patients with a bladder stone, and 10 (52.6%) recurred (30 renal stones). Overall, 30.8% of bladder stones were non-infectious (Table). Among patients recurring after an infectious bladder stone, 30.4% recurred with a non-infectious one. Among patients recurring after a non-infectious stone, 84.6% recurred with a non-infectious one (P = 0.005). Compared with bladder stones, renal stones were more likely to be non-infectious (60.0%, P = 0.003). Of patients with recurrent renal calculi after an infectious stone, 40.0% recurred with

  9. Effect of Repeated Microwave Disinfection on Surface Hardness and Dimensional Accuracy of Two Dental Stone Materials

    Directory of Open Access Journals (Sweden)

    Mahmood Robati Anaraki

    2015-01-01

    Full Text Available There is controversial evidence in relation to the effect of microwave on mechanical properties of stone casts. The present study was designed to evaluate the effect of repeated microwave disinfection on surface hardness and dimensional accuracy of dental stone. In this in vitro study, 48 cylindrical stone samples were prepared using two products of type IV stone to assess surface hardness and 48 impressions were taken from a model and poured by these stones to assess the dimensional accuracy. The evaluation of the samples was carried out consequently by a micro-hardness tester and a digital caliper after the stone samples were exposed to 7 consecutive rounds of 900 watts (W microwave irradiation for five minutes each time after cooling. Data were analyzed by t-test and ANOVA. According to the obtained results, multiple disinfections of the stone casts by microwave do not negatively affect their surface hardness and dimensional accuracy.   Key words: Dental stone; Dimensional accuracy; Hardness; Microwave

  10. Tamsulosin and the spontaneous passage of ureteral stones in children: A multi-institutional cohort study

    Science.gov (United States)

    Tasian, Gregory E.; Cost, Nicholas G.; Granberg, Candace F.; Pulido, Jose E.; Rivera, Marcelino; Schwen, Zeyad; Schulte, Marion; Fox, Janelle A.

    2014-01-01

    Purpose Tamsulosin is associated with increased passage of ureteral stones in adults, but its effectiveness in children is uncertain. We determined the association between tamsulosin and the spontaneous passage of ureteral stones in children. Methods We performed a multi-institutional retrospective cohort study of children ≤ 18 years who presented between 2007 and 2012 with a ureteral stone ≤ 10 mm and were managed with tamsulosin or oral analgesics alone. The outcome was spontaneous stone passage defined as radiographic clearance and/or patient report of passage. Subjects prescribed tamsulosin were matched with subjects prescribed analgesics alone using nearest neighbor propensity score matching to adjust for treatment selection. Conditional logistic regression models were used to estimate the association between tamsulosin and spontaneous passage of ureteral stones, adjusting for stone size and location. Results Of 449 children with ureteral stones, 334 were eligible for inclusion, and complete data were available for 274 children from 4 institutions (99 tamsulosin; 175 analgesics alone). Following case matching, there were no differences in patient age, gender, weight, height, stone size, or stone location between the 99 subjects prescribed tamsulosin and the 99 propensity-score matched subjects prescribed analgesics alone. In the tamsulosin cohort, 55% of ureteral stones passed versus 44% in the analgesics alone cohort (p = 0.03). In multivariate analysis adjusting for stone size and location, tamsulosin was associated with spontaneous passage of ureteral stones (OR 3.31; 95% CI 1.49–7.34). Conclusions The odds of spontaneous passage of ureteral stones were higher in children prescribed tamsulosin versus analgesics alone. PMID:24518765

  11. Can ureteral stones cause pain without causing hydronephrosis?

    Science.gov (United States)

    Song, Yan; Hernandez, Natalia; Gee, Michael S; Noble, Vicki E; Eisner, Brian H

    2016-09-01

    While computerized tomography (CT) is the gold standard for diagnosis of ureterolithiasis, ultrasound is a less costly and radiation-free alternative which is commonly used to evaluate patients with ureteral colic. The purpose of this study was to evaluate the frequency with which patients with ureteral stones and renal colic demonstrate hydronephrosis in order to better understand the evaluation of these patients. Two hundred and forty-eight consecutive patients presenting with ureteral colic and diagnosed with a single unilateral ureteral stone on CT scan in an urban tertiary care emergency department were retrospectively reviewed. Radiology reports were reviewed for stone size, diagnosis, and degree of hydronephrosis. Of the 248 patients evaluated for suspected ureteral stone, 221 (89.1 %) demonstrated any hydronephrosis, while 27 (10.9 %) did not. Hydronephrosis grade, available in 194 patients, was as follows: mild-70.6 %, moderate-27.8 %, and severe-1.5 %. Mean patient age was 47.0 years (SD 15.5), gender distribution was 35.9 % female and 64.1 % male, and mean stone axial diameter was 4.1 mm (SD 2.4). Stone location was as follows: ureteropelvic junction-4.1 %, proximal ureter-21 %, distal ureter-24.9 %, and ureterovesical junction-47.1 %. Axial stone diameter and coronal length (craniocaudal) were both significant predictors of degree of hydronephrosis (ANOVA, p hydronephrosis. In patients with ureteral stones and colic, nearly 11 % do not demonstrate any hydronephrosis and a majority (nearly 71 %) will demonstrate only mild hydronephrosis. Stone diameter appears to be related to degree of hydronephrosis, whereas age, gender, and stone location are not. The lower incidence of hydronephrosis for small stones causing renal colic may explain the lower diagnostic accuracy of ultrasound when compared to CT for detecting ureteral stones.

  12. Use of Local Stone: Successes, Failures and Considerations

    Science.gov (United States)

    Gerns, Edward; Will, Rachel

    2015-04-01

    Stone has been used in construction for thousands of years. Until relatively recently, local stone was used almost exclusively due to limited transportation options and to reduce costs. . Historically, the stone was often taken from nearby fields, known as fieldstone, without any specific quarrying operations and used to create unique assemblages of vernacular buildings. Stone, perhaps more than any other natural building material, has numerous varieties and characteristics within the broader classifications of stone: sedimentary, igneous and metamorphic. In exterior applications, stone historically has been used for foundations, localized cladding elements and in some instances entire building facades. Many of these local stones are appropriate for foundations, but not necessarily for cladding systems, particularly once the stone was quarried and modified rather than used in its natural form. These issues tended to be less significant in historic buildings when wall systems were much thicker and had more redundancies in the cladding systems Since around 1880, the use of these thinner applications of quarried stones as more traditional cladding systems (rather than cladding and structure) has resulted in challenges including unanticipated weathering characteristics, residual stresses and detrimental inclusions. These conditions can result in expensive and extensive repairs and maintenance. Often the options to address these characteristics are limited or potentially drastic depending on the scale of installation. It is important to understand the cause of the issues, understand if these issues are significant and finally how to address them appropriately. Where and how these unique local stones are installed as well as climate and weathering patterns certainly contribute to the potential unanticipated conditions. This presentation will be divided into two general parts. The first will address various stones used historically throughout regions within the United

  13. Temporally variable macroinvertebrate-stone relationships in streams

    DEFF Research Database (Denmark)

    Jacobsen, D.

    2005-01-01

    of fauna parameter and stone variable from different sampling dates (n=9-11) were rarely correlated to any of the measures of stream stability, this study has demonstrated high temporal variability in fauna-stone relationships (CV's of regression slopes). Consequently, temporally un-replicated studies......Stones were used to sample macroinvertebrates and characterise microhabitats at monthly or bimonthly intervals in six Ecuadorian streams covering a gradient in four different stability measures and other stream characteristics. The physical variables current velocity, water depth, horizontal...... of families vs. individuals) were related to the physical characteristics of individual stone habitats. My second objective was to quantify temporal variability in fauna-stone relationships and to analyse if such variability was related to overall stability of stream reaches. Partial Least Squares (PLS...

  14. Instrumental neutron activation analysis of kidney stones

    International Nuclear Information System (INIS)

    Sarmani, S.; Kuan, L.L.; Bakar, M.A.A.

    1990-01-01

    Kidney stone samples of the types calcium oxalate, uric acid, and xanthine were analyzed for their elemental contents by neutron activation analysis to study both the elemental correlation and influence of element on stone precipitation processes. Elements, such as Al, Au, Br, Ca, Cl, Co, Cr, Fe,H, I, K, Mg, Na, Sb, Se, Sr, and Zn, were determined quantitatively. Calcium oxalate stones contained higher concentration of all the elements analyzed compared to uric acid or xanthine stones. The concentrations of Cl, Fe, K, Na, Sr, and Zn were relatively higher than Au, Co, Cr, and Sb. A positive correlation exists between Ca and Zn, whereas a negative correlation exists between Sr and Ca. Zinc may play an important role in the formation of calcium oxalate stone

  15. Application of artificial tactile sensing approach in kidney-stone-removal laparoscopy.

    Science.gov (United States)

    Afshari, Elnaz; Najarian, Siamak; Simforoosh, Nasser

    2010-01-01

    Artificial tactile sensing is a novel method for obtaining different characteristics of a hard object embedded in a soft tissue. In this regard, artificial palpation is one of the most valuable achievements of artificial tactile sensing that can be used in various fields of medicine and more specifically in surgery. In this study, considering the present problems and limitations in kidney-stone-removal laparoscopy, a new application will be presented for artificial tactile sensing approach. Having imitated surgeon's palpation during open surgery and modeled it conceptually, indications of stone existence that appear on the surface of kidney (due to exerting mechanical load) were determined. A number of different cases were created and solved by the software. Using stress distribution contours and stress graphs, it is illustrated that the created stress patterns on the surface of kidney not only show the existence of stone inside, but also its exact location. In fact, the reliability and accuracy of artificial tactile sensing method in detection of kidney stone during laparoscopy is demonstrated by means of finite element analysis. Also, in this paper, the functional principles of tactile system capable of determining the exact location of stone during laparoscopy will be presented.

  16. Stepwise hydrogeological modeling and groundwater flow analysis on site scale (Step 0 and Step 1)

    International Nuclear Information System (INIS)

    Ohyama, Takuya; Saegusa, Hiromitsu; Onoe, Hironori

    2005-05-01

    One of the main goals of the Mizunami Underground Research Laboratory Project is to establish comprehensive techniques for investigation, analysis, and assessment of the deep geological environment. To achieve this goal, a variety of investigations, analysis, and evaluations have been conducted using an iterative approach. In this study, hydrogeological modeling and ground water flow analyses have been carried out using the data from surface-based investigations at Step 0 and Step 1, in order to synthesize the investigation results, to evaluate the uncertainty of the hydrogeological model, and to specify items for further investigation. The results of this study are summarized as follows: 1) As the investigation progresses Step 0 to Step 1, the understanding of groundwater flow was enhanced from Step 0 to Step 1, and the hydrogeological model could be revised, 2) The importance of faults as major groundwater flow pathways was demonstrated, 3) Geological and hydrogeological characteristics of faults with orientation of NNW and NE were shown to be especially significant. The main item specified for further investigations is summarized as follows: geological and hydrogeological characteristics of NNW and NE trending faults are important. (author)

  17. Formation Mechanism of Magnesium Ammonium Phosphate Stones: A Component Analysis of Urinary Nanocrystallites

    Directory of Open Access Journals (Sweden)

    Xin-Yuan Sun

    2015-01-01

    Full Text Available The components of urinary nanocrystallites in patients with magnesium ammonium phosphate (MAP stones were analyzed by X-ray diffraction (XRD, Fourier-transform infrared (FT-IR spectrometer, high-resolution transmission electron microscopy (HRTEM, selected area electron diffraction (SAED, fast Fourier transformation (FFT, and energy-dispersive X-ray spectroscopy (EDS. The main components of the stones were MAP hexahydrate (MAP·6H2O, magnesium hydrogen phosphate trihydrate (MgHPO4·3H2O, and a small amount of calcium phosphate (CaP, while the main components of urinary nanocrystallites were MgHPO4·3H2O, CaP, and MAP monohydrate (MAP·H2O. MAP·H2O induced the formation of MAP stones as seed crystals. MgHPO4·3H2O was accompanied by the appearance of MAP·6H2O. The formation mechanism of MAP stones and influencing factors were discussed on the basis of the components of urine nanocrystallites. A model diagram of MAP stone formation was also put forward based on the results. Formation of MAP stones was closely related to the presence of high amounts of MAP crystallites in urine. Urinary crystallite condition and changes in urine components could indicate the activity of stone diseases.

  18. Grasping the Formless in Stones

    DEFF Research Database (Denmark)

    Aktor, Mikael

    2017-01-01

    and the repertoire of used forms. The chapter demonstrates that neither anthropomorphic perceptions nor the agency of the stone material alone make up the ritual aesthetics in which the stones are involved. Rather, applying concepts from landscape phenomenology and cognitive theories including the role of material...

  19. Can sonography define the chemical composition of gall stones

    International Nuclear Information System (INIS)

    Frentzel-Beyme, B.; Faehndrich, R.; Arnan-Thiele, B.

    1983-01-01

    Eight sonographic patterns caused by gall stones are described. In an attempt to explain these different appearances, 62 stones were analysed chemically and physically. The chemical composition of the stones did not correlate with their sonographic pattern. Cholesterol stones cannot be recognised as such by sonography. The formation of an acoustic shadow depends largely on the position of the stone within the acoustic beam. It therefore follows that the examination must be done by keeping the focal plane of the transducer in proper relationship to the stone. (orig.) [de

  20. Formation of Stone-Wales edge: Multistep reconstruction and growth mechanisms of zigzag nanographene.

    Science.gov (United States)

    Dang, Jing-Shuang; Wang, Wei-Wei; Zheng, Jia-Jia; Nagase, Shigeru; Zhao, Xiang

    2017-10-05

    Although the existence of Stone-Wales (5-7) defect at graphene edge has been clarified experimentally, theoretical study on the formation mechanism is still imperfect. In particular, the regioselectivity of multistep reactions at edge (self-reconstruction and growth with foreign carbon feedstock) is essential to understand the kinetic behavior of reactive boundaries but investigations are still lacking. Herein, by using finite-sized models, multistep reconstructions and carbon dimer additions of a bared zigzag edge are introduced using density functional theory calculations. The zigzag to 5-7 transformation is proved as a site-selective process to generate alternating 5-7 pairs sequentially and the first step with largest barrier is suggested as the rate-determining step. Conversely, successive C 2 insertions on the active edge are calculated to elucidate the formation of 5-7 edge during graphene growth. A metastable intermediate with a triple sequentially fused pentagon fragment is proved as the key structure for 5-7 edge formation. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  1. "Sydney sandstone": Heritage Stone from Australia

    Science.gov (United States)

    Cooper, Barry; Kramar, Sabina

    2014-05-01

    Sydney is Australia's oldest city being founded in 1788. The city was fortunate to be established on an extensive and a relatively undeformed layer of lithified quartz sandstone of Triassic age that has proved to be an ideal building stone. The stone has been long identified by geologists as the Hawkesbury Sandstone. On the other hand the term "Sydney sandstone" has also been widely used over a long period, even to the extent of being utilised as the title of published books, so its formal designation as a heritage stone will immediately formalise this term. The oldest international usage is believed to be its use in the construction of the Stone Store at Kerikeri, New Zealand (1832-1836). In the late 19th century, public buildings such as hospitals, court houses as well as the prominent Sydney Town Hall, Sydney General Post Office, Art Gallery of New South Wales, State Library of New South Wales as well as numerous schools, churches, office building buildings, University, hotels, houses, retaining walls were all constructed using Sydney sandstone. Innumerable sculptures utilising the gold-coloured stone also embellished the city ranging from decorative friezes and capitals on building to significant monuments. Also in the late 19th and early 20th century, Sydney sandstone was used for major construction in most other major Australian cities especially Melbourne, Adelaide and Brisbane to the extent that complaints were expressed that suitable local stone materials were being neglected. Quarrying of Sydney sandstone continues today. In 2000 it was recorded noted that there were 33 significant operating Sydney sandstone quarries including aggregate and dimension stone operations. In addition sandstone continues to be sourced today from construction sites across the city area. Today major dimension stone producers (eg Gosford Quarries) sell Sydney sandstone not only into the Sydney market but also on national and international markets as cladding and paving products

  2. Testing a stepped care model for binge-eating disorder: a two-step randomized controlled trial.

    Science.gov (United States)

    Tasca, Giorgio A; Koszycki, Diana; Brugnera, Agostino; Chyurlia, Livia; Hammond, Nicole; Francis, Kylie; Ritchie, Kerri; Ivanova, Iryna; Proulx, Genevieve; Wilson, Brian; Beaulac, Julie; Bissada, Hany; Beasley, Erin; Mcquaid, Nancy; Grenon, Renee; Fortin-Langelier, Benjamin; Compare, Angelo; Balfour, Louise

    2018-05-24

    A stepped care approach involves patients first receiving low-intensity treatment followed by higher intensity treatment. This two-step randomized controlled trial investigated the efficacy of a sequential stepped care approach for the psychological treatment of binge-eating disorder (BED). In the first step, all participants with BED (n = 135) received unguided self-help (USH) based on a cognitive-behavioral therapy model. In the second step, participants who remained in the trial were randomized either to 16 weeks of group psychodynamic-interpersonal psychotherapy (GPIP) (n = 39) or to a no-treatment control condition (n = 46). Outcomes were assessed for USH in step 1, and then for step 2 up to 6-months post-treatment using multilevel regression slope discontinuity models. In the first step, USH resulted in large and statistically significant reductions in the frequency of binge eating. Statistically significant moderate to large reductions in eating disorder cognitions were also noted. In the second step, there was no difference in change in frequency of binge eating between GPIP and the control condition. Compared with controls, GPIP resulted in significant and large improvement in attachment avoidance and interpersonal problems. The findings indicated that a second step of a stepped care approach did not significantly reduce binge-eating symptoms beyond the effects of USH alone. The study provided some evidence for the second step potentially to reduce factors known to maintain binge eating in the long run, such as attachment avoidance and interpersonal problems.

  3. A study on the utilization of stone powder sludge (III)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chi Kwon; Sohn, Jeong Soo; Kim, Byung Gyu [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1996-12-01

    This study was performed to activate the building stone industry by increasing the recycling amounts of waste resources and minimizing the generation of the environmental pollution materials. In order to utilize the waste stone and stone powder sludge generated from the domestic quarry and cutting process of stone plates, the manufacturing technology of the artificial stone plate as a building material was developed. Based on the first and second year results, this third-year study was performed for manufacturing the large-scale artificial stone plate of 500 x 500 x 20 mm. Also for applying these artificial stone plates to the flooring and interior materials in the building industry, the manufacture of the large-scale artificial stone plates with various patterns and colors was carried out by changing the species and the ratio of raw materials, amounts of binder and molding pressure. Artificial stone plate was composed of waste crushed stone, stone powder sludge and binder which was used for binding waste stone and rock powder each other. In order to investigate the physical properties of large-scale artificial stone, the measure of specific gravity, absorption ratio, P-wave velocity, compressive strength, tensile strength, Young`s modulus, and Poisson`s ratio were carried out. As a result of testing physical properties, there was no difference between small-scale artificial stone and large-scale one. At the optimum conditions it was shown that the properties of artificial stones were as follows, 2.32 of specific gravity, 0.33 of water-absorption ratio, 780 kg/cm{sup 2} of compressive strength and 98 kg/cm{sup 2} of tensile strength. Based on the above results, the preliminary economic estimation on the manufacture of the artificial stone plate was carried out. It was shown that the manufacturing cost of the artificial stone plate was 18,000 won/m{sup 2}, which was merely half that of natural stone plate, and the application of these on the building stone industry

  4. ADDING A NEW STEP WITH SPATIAL AUTOCORRELATION TO IMPROVE THE FOUR-STEP TRAVEL DEMAND MODEL WITH FEEDBACK FOR A DEVELOPING CITY

    Directory of Open Access Journals (Sweden)

    Xuesong FENG, Ph.D Candidate

    2009-01-01

    Full Text Available It is expected that improvement of transport networks could give rise to the change of spatial distributions of population-related factors and car ownership, which are expected to further influence travel demand. To properly reflect such an interdependence mechanism, an aggregate multinomial logit (A-MNL model was firstly applied to represent the spatial distributions of these exogenous variables of the travel demand model by reflecting the influence of transport networks. Next, the spatial autocorrelation analysis is introduced into the log-transformed A-MNL model (called SPA-MNL model. Thereafter, the SPA-MNL model is integrated into the four-step travel demand model with feedback (called 4-STEP model. As a result, an integrated travel demand model is newly developed and named as the SPA-STEP model. Using person trip data collected in Beijing, the performance of the SPA-STEP model is empirically compared with the 4-STEP model. It was proven that the SPA-STEP model is superior to the 4-STEP model in accuracy; most of the estimated parameters showed statistical differences in values. Moreover, though the results of the simulations to the same set of assumed scenarios by the 4-STEP model and the SPA-STEP model consistently suggested the same sustainable path for the future development of Beijing, it was found that the environmental sustainability and the traffic congestion for these scenarios were generally overestimated by the 4-STEP model compared with the corresponding analyses by the SPA-STEP model. Such differences were clearly generated by the introduction of the new modeling step with spatial autocorrelation.

  5. The composition of urinary stones in central sindh

    International Nuclear Information System (INIS)

    Memon, J.M.; Naqvi, S.Q.H.

    2014-01-01

    To determine chemical analysis of urinary stones of central sindh. Study design: Prospective and randomized study. Setting: Department of Surgery and Pathology of Peoples University of Medical and Health Sciences Nawabshah. Duration of study: Three years from May 2008 to May 2011. Material and Methods: Total 106 urolith patients who underwent open stone surgery were included in the study. EDTA Titration used for determination of calcium ions and determination of oxalate, phosphate, magnesium, ammonia, uric acid and cystine stones was carried out using spectrophotometer. These patients were asked to fill out a proforma with parameters of age, sex, radiological location of stone and chemical composition of surgically recovered stones. The stone analysis findings were reviewed and compared with other reported series Results: In this study 75(70.75%) patients were male and 31 (29.25%) female. Male to female ratio was of 2.41:1. The age ranged from 1 to 70 years with the mean of 22.69 years. The peak incidence of upper urinary tract stone in 20-30 years and lower urinary tract stones in both sexes was under 10 years. Anatomical location of stone showed 48(45.29%) renal, 13(12.26%) ureteric and 45(42.45%) bladder calculi. Chemical analysis revealed 56(52.8%) calcium oxalate, 7(6.6%) calcium phosphate, 11(10.3%) ammonium urate, 18(16.9%) uric acid, 13(12.2%) Sturvite and 1(0.9%) cystine calculi. Conclusion: It was concluded that urolithiasis is predominantly male disease. No age group was spared to stone disease. Calcium oxalate, uric acid, ammonium urate and mixed calculi are the main types in our study due to poor nutritional status, poverty and inadequate health facilities. Considering that knowledge of stone composition is of utmost importance to modify the incidence of urolithiasis. (author)

  6. Evaluation of stone volume distribution in renal collecting system as a predictor of stone-free rate after percutaneous nephrolithotomy: a retrospective single-center study.

    Science.gov (United States)

    Atalay, Hasan Anıl; Canat, Lutfi; Bayraktarlı, Recep; Alkan, Ilter; Can, Osman; Altunrende, Fatih

    2017-06-23

    We analyzed our stone-free rates of PNL with regard to stone burden and its ratio to the renal collecting system volume. Data of 164 patients who underwent PNL were analyzed retrospectively. Volume segmentation of renal collecting system and stones were done using 3D segmentation software with the images obtained from CT data. Analyzed stone volume (ASV) and renal collecting system volume (RCSV) were measured and the ASV-to-RCSV ratio was calculated after the creation of a 3D surface volume rendering of renal stones and the collecting system. Univariate and multivariate statistical analyses were performed to determine factors affecting stone-free rates; also we assessed the predictive accuracy of the ASV-to-RCSV ratio using the receiving operating curve (ROC) and AUC. The stone-free rate of PNL monotherapy was 53% (164 procedures).The ASV-to-RCSV ratio and calyx number with stones were the most influential predictors of stone-free status (OR 4.15, 95% CI 2.24-7.24, renal collecting system, which is calculated using the 3D volume segmentation method, is a significant determinant of the stone-free rate before PCNL surgery. It could be used as a single guide variable by the clinician before renal stone surgery to predict extra requirements for stone clearance.

  7. Combined retrograde flexible ureteroscopic lithotripsy with holmium YAG laser for renal calculi associated with ipsilateral ureteral stones.

    Science.gov (United States)

    Cocuzza, Marcello; Colombo, Jose R; Ganpule, Arvind; Turna, Burak; Cocuzza, Antonio; Dhawan, Divyar; Santos, Bruno; Mazzucchi, Eduardo; Srougi, Miguel; Desai, Mahesh; Desai, Mihir

    2009-02-01

    The purpose of this study was to evaluate the effectiveness of combined ureteroscopic holmium YAG lithotripsy for renal calculi associated with ipsilateral ureteral stones. Between August 2002 and March 2007, retrograde flexible ureteroscopic stone treatment was attempted in 351 cases. Indication for treatment was concurrent symptomatic ureteral stones in 63 patients (group I). Additional operative time and perioperative complication rates were compared to a group of 39 patients submitted to ureteroscopic treatment for ureteral calculi exclusively (group II). Mean ureteral stone size was 8.0 +/- 2.6 mm and 8.1 +/- 3.4 mm for groups I and II, respectively. Mean operative time for group I was 67.9 +/- 29.5 minutes and for group 2 was 49.3 +/- 13.2 minutes (p stone size was 10.7 +/- 6.4 mm, overall stone free rate in group I was 81%. However, considering only patients with renal stones smaller than 15 mm, the stone free rate was 88%. Successful treatment occurred in 81% of patients presenting lower pole stones, but only 76% of patients with multiple renal stones became stone free. As expected, stone free rate showed a significant negative correlation with renal stone size (p = 0.03; r = -0.36). Logistic regression model indicated an independent association of renal stones smaller than 15 mm and stone free rate (OR = 13.5; p = 0.01). Combined ureteroscopic treatment for ureteral and ipsilateral renal calculi is a safe and attractive option for patients presenting for symptomatic ureteral stone and ipsilateral renal calculi smaller than 15 mm.

  8. Ornamental Stones and Gemstones: The limits of heritage stone designation: The case for and against Australian Precious Opal

    Science.gov (United States)

    Cooper, Barry

    2015-04-01

    When the international designation of natural stone types was first mooted in 2007, stones that were utilised in building and construction were the primary focus of attention. However following public discussion it soon became apparent that sculptural stones, stone used for utilitarian purposes such as millstones, as well as archaeological materials including stones used by early man could all be positively assessed as a potential Global Heritage Stone Resource (GHSR). Over the past 2 years it has been realised there is also a range of ornamental and semi-precious stones that may also be considered in the same international context. Examples in this respect include Imperial Porphyry sourced from Egypt that was much prized in the ancient world and "Derbyshire Blue John" a variety of fluorspar from central England that was used for vases, chalices, urns, candle sticks, jars, bowls door, jewellery and fire-place surrounds, especially in the 18th and 19th centuries. It is at this point that rock materials, sometimes used as gemstones, impinge on the domain of typical heritage stones. In Australia, the gemstone most identifiable with the country is precious opal formed by sedimentary processes in the Great Artesian Basin. In this paper the question is asked whether "Australian Precious Opal" could be or should be considered as a heritage stone of international significance. Immediately Australian Precious Opal satisfies several GHSR criteria including historic use for more than 50 years and wide-ranging utilisation for prestige jewellery around the world. It is also recognised as a cultural icon including association with national identity in Australia as it is legally defined as Australia's "National Gemstone" as well as being the "Gemstone Emblem" for the State of South Australia. Opal continues to be mined. Designation of Australian Precious Opal as a Global Heritage Stone Resource would likely involve formal international recognition of Australian opal in the

  9. Predictions of outcomes of renal stones after extracorporeal shock wave lithotripsy from stone characteristics determined by unenhanced helical computed tomography: a multivariate analysis

    International Nuclear Information System (INIS)

    Wang, Li-Jen; Wong, Yon-Cheong; Chuang, Cheng-Keng; Chu, Sheng-Hsien; Chen, Chih-Shou; Chiang, Yang-Jen; See, Lai-Chu

    2005-01-01

    The aim of our study is to analyze the relationships between the characteristics of renal stones determined by unenhanced helical computed tomography (UHCT) and their outcomes after extracorporeal shock wave lithotripsy (ESWL) as well as to predict ESWL outcomes of renal stones by their UHCT characteristics with the use of multivariate analysis. During a 7-month period, 80 adult patients with renal stones underwent ESWL as well as UHCT both before and 3 months after ESWL. Of the 80 patients, 42 patients were classified as ESWL successes and 38 as ESWL failures based on their post-ESWL UHCT findings. For pre-ESWL UHCT, a stone number of more than 2 (P=0.0236), a maximal stone size of greater than 12 mm (P 3 (P 3 (P=0.0003), the presence of nonround/oval stones (P=0.0072) and a maximal stone density of more than 900 HU (P=0.0430) were statistically significant predictors of a failure outcome for ESWL. Thus, the analysis of stone characteristics of renal stones by UHCT is helpful in selecting appropriate patients undergoing ESWL for favorable outcomes and reduces the overall costs of the treatment of renal stones. (orig.)

  10. Which is better? Guy's versus S.T.O.N.E. nephrolithometry scoring systems in predicting stone-free status post-percutaneous nephrolithotomy.

    Science.gov (United States)

    Noureldin, Yasser A; Elkoushy, Mohamed A; Andonian, Sero

    2015-11-01

    The aim of the present study was to compare the accuracy of the Guy's and S.T.O.N.E. scoring systems in predicting percutaneous nephrolithotomy (PCNL) outcomes. After obtaining ethics approval, medical records of patients undergoing PCNL between 2009 and 2013 at a tertiary stone center were retrospectively reviewed. Guy's and S.T.O.N.E. scoring systems were calculated. Regression analysis and ROC curves were performed. A total of 185 PCNLs were reviewed. The overall stone-free rate was 71.9 % with a complication rate of 16.2 %. When compared to patients with residual fragments, stone-free patients had significantly lower Guy's grade (2.7 vs. 2; p stone-free status, OR 0.4 (p r = 0.3, p r = 0.4, p r = 0.2, p = 0.001 and r = 0.3, p stone-free status. Other factors not included in either scoring system may need to be incorporated in the future to increase their accuracy.

  11. Do You Have Symptoms of a Kidney Stone?

    Science.gov (United States)

    ... Or, the stone will be removed with treatment. Dogs, Cats, and Kidney Stones Humans aren't the only ones affected by kidney and bladder stones. Dogs, cats, and other animals can also have kidney ...

  12. Gypsum accumulation on carbonate stone

    Science.gov (United States)

    McGee, E.S.; Mossotti, V.G.

    1992-01-01

    The accumulation of gypsum on carbonate stone has been investigated through exposure of fresh samples of limestone and marble at monitored sites, through examination of alteration crusts from old buildings and through laboratory experiments. Several factors contribute to gypsum accumulation on carbonate stone. Marble or limestone that is sheltered from direct washing by rain in an urban environment with elevated pollution levels is likely to accumulate a gypsum crust. Crust development may be enhanced if the stone is porous or has an irregular surface area. Gypsum crusts are a surficial alteration feature; gypsum crystals form at the pore opening-air interface, where evaporation is greatest.

  13. Modeling of lung cancer risk due to radon exhalation of granite stone in dwelling houses

    Directory of Open Access Journals (Sweden)

    Akbar Abbasi

    2017-01-01

    Conclusions: The estimated numbers of lung cancer deaths attributable to indoor radon due to granite stones in 2013 were 145 (3.33% and 103 (2.37% for poor and normal ventilation systems, respectively. According to our estimations, the values of 3.33% and 2.37% of lung cancer deaths in 2013 are attributed to radon exhalation of granite stones with poor and normal ventilation systems, respectively.

  14. Surgical versus endoscopic treatment of bile duct stones

    DEFF Research Database (Denmark)

    Martin, D J; Vernon, D R; Toouli, J

    2006-01-01

    10% to 18% of patients undergoing cholecystectomy for gallstones have common bile duct (CBD) stones. Treatment options for these stones include pre- or post-operative endoscopic retrograde cholangiopancreatography (ERCP) or open or laparoscopic surgery.......10% to 18% of patients undergoing cholecystectomy for gallstones have common bile duct (CBD) stones. Treatment options for these stones include pre- or post-operative endoscopic retrograde cholangiopancreatography (ERCP) or open or laparoscopic surgery....

  15. Role of alpha-1 blocker in expulsion of stone fragments after extracorporeal shock wave lithotripsy for renal stones

    International Nuclear Information System (INIS)

    Pirzada, A.J.; Anwar, A.; Javed, A.; Memon, I.; Mohammad, A.

    2011-01-01

    Background: Renal stone disease is a significant and worldwide health problem. Recent advances in stone management have allowed kidney stones to be treated using extracorporeal shock wave lithotripsy (ESWL), uretero-renoscopy (URS), and percutaneous nephrostolithotomy (PCNL). Recently, medical expulsion therapy (MET) has been investigated as a supplement to observation in an effort to improve spontaneous stone passage rates. Patients and Methods: This study was a randomized, controlled, prospective study to determine whether the administration of Alpha-1-adrenergic receptor antagonists as an adjunctive medical therapy, increases the efficacy of ESWL to treat renal stones. Sixty patients with renal stones of 0.5-1.5 Cm in size (average size 1.2 Cm) were included in this study underwent ESWL followed by administration of Alpha-1-adrenergic receptor antagonists at department of Urology Liaquat National Hospital Karachi from Feb 2008 to Sept 2008. This was a comparative study and patients were divided into two groups. In group A patients received conventional treatment Diclofenac sodium, Anti Spasmodic (Drotaverine HCl) as required and Proton Pump inhibitor (Omeprazole 20 mg) once daily after shock wave lithotripsy. In group B patients received alpha-1 blocker, Alfuzosin HCl 5 mg twice daily in addition to conventional treatment. All patients were instructed to drink a minimum of 2 litres water daily. Ultrasound guided Dornier Alpha Impact Lithotripter was utilised for shock wave lithotripsy. Results: Of the 60 patients, 76.7% of those receiving Alfuzosin and 46.7% of controls had achieved clinical success at 1 month (p=0.01). The mean cumulative diclofenac dose was 485 mg per patient in the Alfuzosin group and 768 mg per patient in the control group (p=0.002). This difference was statistically significant. Conclusion: Alfuzosin therapy as an adjunctive medical therapy after ESWL is more effective than lithotripsy alone for the treatment of patients with large renal

  16. Use of the probability of stone formation (PSF) score to assess stone forming risk and treatment response in a cohort of Brazilian stone formers.

    Science.gov (United States)

    Turney, Benjamin; Robertson, William; Wiseman, Oliver; Amaro, Carmen Regina P R; Leitão, Victor A; Silva, Isabela Leme da; Amaro, João Luiz

    2014-01-01

    The aim was to confirm that PSF (probability of stone formation) changed appropriately following medical therapy on recurrent stone formers. Data were collected on 26 Brazilian stone-formers. A baseline 24-hour urine collection was performed prior to treatment. Details of the medical treatment initiated for stone-disease were recorded. A PSF calculation was performed on the 24 hour urine sample using the 7 urinary parameters required: voided volume, oxalate, calcium, urate, pH, citrate and magnesium. A repeat 24-hour urine sample was performed for PSF calculation after treatment. Comparison was made between the PSF scores before and during treatment. At baseline, 20 of the 26 patients (77%) had a high PSF score (> 0.5). Of the 26 patients, 17 (65%) showed an overall reduction in their PSF profiles with a medical treatment regimen. Eleven patients (42%) changed from a high risk (PSF > 0.5) to a low risk (PSF 0.5) during both assessments. The PSF score reduced following medical treatment in the majority of patients in this cohort.

  17. Use of the probability of stone formation (PSF score to assess stone forming risk and treatment response in a cohort of Brazilian stone formers

    Directory of Open Access Journals (Sweden)

    Benjamin Turney

    2014-08-01

    Full Text Available Introduction The aim was to confirm that PSF (probability of stone formation changed appropriately following medical therapy on recurrent stone formers. Materials and Methods Data were collected on 26 Brazilian stone-formers. A baseline 24-hour urine collection was performed prior to treatment. Details of the medical treatment initiated for stone-disease were recorded. A PSF calculation was performed on the 24 hour urine sample using the 7 urinary parameters required: voided volume, oxalate, calcium, urate, pH, citrate and magnesium. A repeat 24-hour urine sample was performed for PSF calculation after treatment. Comparison was made between the PSF scores before and during treatment. Results At baseline, 20 of the 26 patients (77% had a high PSF score (> 0.5. Of the 26 patients, 17 (65% showed an overall reduction in their PSF profiles with a medical treatment regimen. Eleven patients (42% changed from a high risk (PSF > 0.5 to a low risk (PSF 0.5 during both assessments. Conclusions The PSF score reduced following medical treatment in the majority of patients in this cohort.

  18. Urinary stone composition in Oman: with high incidence of cystinuria.

    Science.gov (United States)

    Al-Marhoon, Mohammed S; Bayoumi, Riad; Al-Farsi, Yahya; Al-Hinai, Abdullhakeem; Al-Maskary, Sultan; Venkiteswaran, Krishna; Al-Busaidi, Qassim; Mathew, Josephkunju; Rhman, Khalid; Sharif, Omar; Aquil, Shahid; Al-Hashmi, Intisar

    2015-06-01

    Urinary stones are a common problem in Oman and their composition is unknown. The aim of this study is to analyze the components of urinary stones of Omani patients and use the obtained data for future studies of etiology, treatment, and prevention. Urinary stones of 255 consecutive patients were collected at the Sultan Qaboos University Hospital. Stones were analyzed by Fourier transform infrared spectrophotometer. The biochemical, metabolic, and radiological data relating to the patients and stones were collected. The mean age was 41 years, with M:F ratio of 3.7:1. The common comorbidities associated with stone formation were hypertension; diabetes, benign prostate hyperplasia; urinary tract infection; obesity; and atrophic kidney. The common presentation was renal colic and flank pain (96%). Stones were surgically retrieved in 70% of patients. Mean stone size was 9 ± 0.5 mm (range 1.3-80). Stone formers had a BMI ≥ 25 in 56% (P = 0.006) and positive family history of stones in 3.8%. The most common stones in Oman were as follows: Calcium Oxalates 45% (114/255); Mixed calcium phosphates & calcium oxalates 22% (55/255); Uric Acid 16% (40/255); and Cystine 4% (10/255). The most common urinary stones in Oman are Calcium Oxalates. Overweight is an important risk factor associated with stone formation. The hereditary Cystine stones are three times more common in Oman than what is reported in the literature that needs further genetic studies.

  19. Pattern of urinary tract stone diseases in Mekelle, Ethiopia.

    Science.gov (United States)

    Alemu, Mekonnen Hagos

    2008-07-01

    To evaluate and analyze the pattern of patients with urinary stone diseases admitted to Mekelle Hospital. Between Sept 2003 to Sept 2006, 102 patients with urinary stone disease were admitted to Mekelle Hospital. In this descriptive retrospective audit, case notes were obtained from medical record office and were analyzed for age, sex, localization of the stone disease and the geographic back grounds. Seventy six (74.5%) of the patients were males and 26 (25.5%) were females. There were 102 (13.6%) cases of urinary stone disease admitted to Mekelle Hospital out of 750 total admissions for urological disease for intervention in the surgical ward during the study period. There were 76 (74.5%) males and 26 (25.5%) females and the sex ratio was (M: F: 2.9:1). Most (46.0%) of the urinary stone diseases were between 0-19 year age group both in males and females. The median age was 20 years (range from 2-74 years) and the mean was 25.4 years. Urinary bladder stones were the most common urinary tract stone diseases accounting for 47 (46.0%) followed by renal stones 29 (28.4%), ureteric 16 (15.6%) and urethral 10 (9.8%) stone disease; in that order of frequency. The geographical back ground of the patients with urinary tract stone disease in this report has shown that majorities (53.7%) were from urban and the remaining (44.2%) were from the rural areas. This study has depicted that urinary bladder stone diseases are the most common stone diseases affecting the younger age group. Since this is an institutional based study, it underestimates the magnitude and the pattern of urinary stone diseases at all level. Nevertheless, the audit provides useful information on the socio demographic variables, localization and the geographic back ground of the patients.

  20. Evaluation of Technetium Getters to Improve the Performance of Cast Stone

    International Nuclear Information System (INIS)

    Neeway, James J.; Qafoku, Nikolla P.; Serne, R. Jeffrey; Lawter, Amanda R.; Stephenson, John R.; Lukens, Wayne W.; Westsik, Joseph H.

    2015-01-01

    Cast Stone has been selected as the preferred waste form for solidification of aqueous secondary liquid effluents from the Hanford Tank Waste Treatment and Immobilization Plant (WTP) process condensates and low-activity waste (LAW) melter off-gas caustic scrubber effluents. Cast Stone is also being evaluated as a supplemental immobilization technology to provide the necessary LAW treatment capacity to complete the Hanford tank waste cleanup mission in a timely and cost effective manner. One of the major radionuclides that Cast Stone has the potential to immobilize is technetium (Tc). The mechanism for immobilization is through the reduction of the highly mobile Tc(VII) species to the less mobile Tc(IV) species by the blast furnace slag (BFS) used in the Cast Stone formulation. Technetium immobilization through this method would be beneficial because Tc is one of the most difficult contaminants to address at the U.S. Department of Energy (DOE) Hanford Site due to its complex chemical behavior in tank waste, limited incorporation in mid- to high-temperature immobilization processes (vitrification, steam reformation, etc.), and high mobility in subsurface environments. In fact, the Tank Closure and Waste Management Environmental Impact Statement for the Hanford Site, Richland, Washington (TC&WM EIS) identifies technetium-99 ( 99 Tc) as one of the radioactive tank waste components contributing the most to the environmental impact associated with the cleanup of the Hanford Site. The TC&WM EIS, along with an earlier supplemental waste-form risk assessment, used a diffusion-limited release model to estimate the release of different contaminants from the WTP process waste forms. In both of these predictive modeling exercises, where effective diffusivities based on grout performance data available at the time, groundwater at the 100-m down-gradient well exceeded the allowable maximum permissible concentrations for 99 Tc. (900 pCi/L). Recent relatively short-term (63 day

  1. Evaluation of Technetium Getters to Improve the Performance of Cast Stone

    Energy Technology Data Exchange (ETDEWEB)

    Neeway, James J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Qafoku, Nikolla P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Serne, R. Jeffrey [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lawter, Amanda R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stephenson, John R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lukens, Wayne W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Westsik, Joseph H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-11-01

    Cast Stone has been selected as the preferred waste form for solidification of aqueous secondary liquid effluents from the Hanford Tank Waste Treatment and Immobilization Plant (WTP) process condensates and low-activity waste (LAW) melter off-gas caustic scrubber effluents. Cast Stone is also being evaluated as a supplemental immobilization technology to provide the necessary LAW treatment capacity to complete the Hanford tank waste cleanup mission in a timely and cost effective manner. One of the major radionuclides that Cast Stone has the potential to immobilize is technetium (Tc). The mechanism for immobilization is through the reduction of the highly mobile Tc(VII) species to the less mobile Tc(IV) species by the blast furnace slag (BFS) used in the Cast Stone formulation. Technetium immobilization through this method would be beneficial because Tc is one of the most difficult contaminants to address at the U.S. Department of Energy (DOE) Hanford Site due to its complex chemical behavior in tank waste, limited incorporation in mid- to high-temperature immobilization processes (vitrification, steam reformation, etc.), and high mobility in subsurface environments. In fact, the Tank Closure and Waste Management Environmental Impact Statement for the Hanford Site, Richland, Washington (TC&WM EIS) identifies technetium-99 (99Tc) as one of the radioactive tank waste components contributing the most to the environmental impact associated with the cleanup of the Hanford Site. The TC&WM EIS, along with an earlier supplemental waste-form risk assessment, used a diffusion-limited release model to estimate the release of different contaminants from the WTP process waste forms. In both of these predictive modeling exercises, where effective diffusivities based on grout performance data available at the time, groundwater at the 100-m down-gradient well exceeded the allowable maximum permissible concentrations for 99Tc. (900 pCi/L). Recent relatively

  2. The "Global Heritage Stone Resource": Past, Present and Future

    Science.gov (United States)

    Cooper, Barry

    2013-04-01

    The "Global Heritage Stone Resource" designation arose in 2007 as a suggested mechanism to enhance international recognition of famous dimension stones. There were also many aspects of dimension stone study that had no formal recognition in mainstream geology and which could be recognised in a formal geological sense via an internationally acceptable geological standard. Such a standard could also receive recognition by other professionals and the wider community. From the start, it was appreciated that active quarrying would an important aspect of the designation so a designation different to any other standard was needed. Also the project was linked to the long-established Commission C-10 Building Stone and Ornamental Rocks of the International Association of Engineering Geology and the Environment (IAEG C-10). Since 2007, the "Global Heritage Stone Resource" (GHSR) proposal has evolved in both in stature and purpose due to an increasing number of interested international correspondents that were actively sought via conference participation. The "English Stone Forum" in particular was pursuing similar aims and was quick to advise that English dimension stone types were being recognised as having international, national or regional importance. Furthermore the proposed designation was suggested as to having significant value in safeguarding designated stone types whilst also providing a potential mechanism in preventing heritage stone replacement by cheap substitutes. During development it also became apparent that stone types having practical applications such as roofing slates and millstones or even stone types utilised by prehistoric man can also be recognised by the new designation. The heritage importance of architects was also recognised. Most importantly an international network evolved, primarily including geologists, that now seems to be the largest international grouping of dimension stone professionals. This has assisted the project to affiliate with the

  3. Extracorporeal Shockwave Lithotripsy of Primary Intrahepatic Stones

    Science.gov (United States)

    Kim, Myung Hwan; Lee, Sung Koo; Min, Young Il; Lee, Mun Gyu; Sung, Kyu Bo; Cho, Kyung Sik; Lee, Sung Gyu; Min, Pyung Chul

    1992-01-01

    Extracorporeal shockwave lithothripsy (ESWL) was performed in intrahepatic stone patients (n = 18) by Dornier MPL 9,000 with ultrasound guidance. The patients had T-tube (n = 9) or percutaneous transhepatic biliary drainge tube (n = 9). Average treatment session was four and shock-wave numbers were in the range of 3,064 to 12,000 (average 6,288 shocks). Intrahepatic stones were removed completely in 16 patients over a 3 month period by ESWL and combined stone extraction maneuver such as cholangioscopic or interventional radiologic method. Extracorporeal shockwave lithothripsy was very helpful in facilitating extraction of stones in unfavorable locations or located above the severe stricture. In summary, extracorporeal Shockwave lithotripsy, followed by percutaneous stone extraction, will provide an improvement in the success rate and duration of treatment required for complete removal of primary hepatolithiasis. PMID:1477027

  4. Production and characterization of composite stone

    International Nuclear Information System (INIS)

    Leirose, G.D.; Lameiras, F.S.

    2012-01-01

    Composite stone is a product similar to natural granite or marble, produced with particles of these materials. This material is used like natural stone as lining. The fabrication of artificial stones using residues of banded iron formations is a promising alternative to its actual destination (storage in dam). This research aims the characterization of composite stone to prove the efficacy of this kind of processing. It was used first, natural quartz as a raw material. The patterns of the samples were confirmed by IR spectra and XRD patterns, ensuring the reproducibility of processing applied. Moreover, this material is homogeneous, with low porosity and high flexural strength, confirmed by its structural characterization. Thus, it can be affirmed that the process chosen is suitable, enabling the application of this methodology to the use of waste. (author)

  5. Effectiveness of Treatment Modalities on Kidney Stone Recurrence.

    Science.gov (United States)

    Zisman, Anna L

    2017-10-06

    Nephrolithiasis is highly prevalent across all demographic groups in the Western world and beyond, and its incidence rates are rising. In addition to the morbidity of the acute event, stone disease often becomes a lifelong problem that requires preventative therapy to diminish ongoing morbidity. Across the majority of stone types, increased fluid intake and targeted dietary modifications are mainstays of therapy. Specific dietary interventions associated with reduced calcium stone risk include adequate dietary calcium intake and restriction of sodium, protein, and oxalate intake, among others. Pharmaceutical therapy may be required if lifestyle changes are insufficient to minimize risk of stone recurrence, and must be targeted to the specific metabolic abnormalities portending risk for a given patient. Therapeutic options for idiopathic calcium stone disease include thiazides, citrate salts, and uric acid-lowering agents. Alkali salts are also the treatment of choice for uric acid stone disease. Management of struvite stone disease is largely surgical, but acetohydroxamic acid is a proven second line therapy. Cystinuria requires lifestyle modifications and may call for thiol-binding agents. Significant heterogeneity of the clinical population with stone disease has previously limited opportunities for large randomized controlled trials. However, as clinical phenotypes and genotypes are increasingly clarified, there are mounting opportunities for targeted randomized controlled trials in stone prevention. In the meantime, the currently available evidence for both lifestyle and pharmacologic interventions is reviewed herein. Copyright © 2017 by the American Society of Nephrology.

  6. CT Texture Analysis of Ex Vivo Renal Stones Predicts Ease of Fragmentation with Shockwave Lithotripsy.

    Science.gov (United States)

    Cui, Helen W; Devlies, Wout; Ravenscroft, Samuel; Heers, Hendrik; Freidin, Andrew J; Cleveland, Robin O; Ganeshan, Balaji; Turney, Benjamin W

    2017-07-01

    Understanding the factors affecting success of extracorporeal shockwave lithotripsy (SWL) would improve informed decision-making on the most appropriate treatment modality for an individual patient. Although stone size and skin-to-stone distance do correlate with fragmentation efficacy, it has been shown that stone composition and architecture, as reflected by structural heterogeneity on CT, are also important factors. This study aims to determine if CT texture analysis (CTTA), a novel, nondestructive, and objective tool that generates statistical metrics reflecting stone heterogeneity, could have utility in predicting likelihood of SWL success. Seven spontaneously passed, intact renal tract stones, were scanned ex vivo using standard CT KUB and micro-CT. The stones were then fragmented in vitro using a clinical lithotripter, after which, chemical composition analysis was performed. CTTA was used to generate a number of metrics that were correlated to the number of shocks needed to fragment the stone. CTTA metrics reflected stone characteristics and composition, and predicted ease of SWL fragmentation. The strongest correlation with number of shocks required to fragment the stone was mean Hounsfield unit (HU) density (r = 0.806, p = 0.028) and a CTTA metric measuring the entropy of the pixel distribution of the stone image (r = 0.804, p = 0.039). Using multiple linear regression analysis, the best model showed that CTTA metrics of entropy and kurtosis could predict 92% of the outcome of number of shocks needed to fragment the stone. This was superior to using stone volume or density. CTTA metrics entropy and kurtosis have been shown in this experimental ex vivo setting to strongly predict fragmentation by SWL. This warrants further investigation in a larger clinical study for the contribution of CT textural metrics as a measure of stone heterogeneity, along with other known clinical factors, to predict likelihood of SWL success.

  7. Efficacy of the lithotripsy in treating lower pole renal stones.

    Science.gov (United States)

    Cui, Helen; Thomee, Eeke; Noble, Jeremy G; Reynard, John M; Turney, Benjamin W

    2013-06-01

    Use of extracorporeal lithotripsy is declining in North America and many European countries despite international guidelines advocating it as a first-line therapy. Traditionally, lithotripsy is thought to have poor efficacy at treating lower pole renal stones. We evaluated the success rates of lithotripsy for lower pole renal stones in our unit. 50 patients with lower pole kidney stones ≤15 mm treated between 3/5/11 and 19/4/12 were included in the study. Patients received lithotripsy on a fixed-site Storz Modulith SLX F2 lithotripter according to a standard protocol. Clinical success was defined as stone-free status or asymptomatic clinically insignificant residual fragments (CIRFs) ≤3 mm at radiological follow-up. The mean stone size was 7.8 mm. The majority of stones (66 %) were between 5 and 10 mm. 28 % of stones were between 10 and 15 mm. For solitary lower pole stones complete stone clearance was achieved in 63 %. Total stone clearance including those with CIRFs was achieved in 81 % of patients. As expected, for those with multiple lower pole stones the success rates were lower: complete clearance was observed in 39 % and combined clearance including those with CIRFs was 56 %. Overall, complete stone clearance was observed in 54 % of patients and clearance with CIRFs was achieved in 72 % of patients. Success rate could not be attributed to age, stone size or gender. Our outcome data for the treatment of lower pole renal stones (≤15 mm) compare favourably with the literature. With this level of stone clearance, a non-invasive, outpatient-based treatment like lithotripsy should remain the first-line treatment option for lower pole stones. Ureteroscopy must prove that it is significantly better either in terms of clinical outcome or patient satisfaction to justify replacing lithotripsy.

  8. Factors affecting GEBV accuracy with single-step Bayesian models.

    Science.gov (United States)

    Zhou, Lei; Mrode, Raphael; Zhang, Shengli; Zhang, Qin; Li, Bugao; Liu, Jian-Feng

    2018-01-01

    A single-step approach to obtain genomic prediction was first proposed in 2009. Many studies have investigated the components of GEBV accuracy in genomic selection. However, it is still unclear how the population structure and the relationships between training and validation populations influence GEBV accuracy in terms of single-step analysis. Here, we explored the components of GEBV accuracy in single-step Bayesian analysis with a simulation study. Three scenarios with various numbers of QTL (5, 50, and 500) were simulated. Three models were implemented to analyze the simulated data: single-step genomic best linear unbiased prediction (GBLUP; SSGBLUP), single-step BayesA (SS-BayesA), and single-step BayesB (SS-BayesB). According to our results, GEBV accuracy was influenced by the relationships between the training and validation populations more significantly for ungenotyped animals than for genotyped animals. SS-BayesA/BayesB showed an obvious advantage over SSGBLUP with the scenarios of 5 and 50 QTL. SS-BayesB model obtained the lowest accuracy with the 500 QTL in the simulation. SS-BayesA model was the most efficient and robust considering all QTL scenarios. Generally, both the relationships between training and validation populations and LD between markers and QTL contributed to GEBV accuracy in the single-step analysis, and the advantages of single-step Bayesian models were more apparent when the trait is controlled by fewer QTL.

  9. Can Hounsfield Unit Value Predict Type of Urinary Stones?

    Directory of Open Access Journals (Sweden)

    Alper Gok

    2014-03-01

    Full Text Available Aim: Aim of this study is to determine the role of Hounsfield unit (HU in predicting results of stone analysis. Material and Method: This study included 199 patients to whom percutaneous nephrolithotomy (PNL procedures were applied between January 2008 and May 2011 in our clinic. Before the procedure HU values of kidney stones were measured using non-contrast computed tomography. After the operation, obtained stone samples were analysed using X-ray diffraction technique. HU values were compared with stone analysis results. Results: Stone analysis revealed eight different stone types. Distribution of stone types and HU value ranges were as follows: 85% calcium oxalate monohydrate, 730-1130 HU; 38% calcium oxalate dihydrate, 510-810 HU; 21% uric acid, 320-550 HU; 23% struvite, 614-870 HU; 7% calcium hydrogene phosphate, 1100-1365 HU; 3% cystine, 630-674 HU; 15% mixed uric acid plus calcium oxalate, 499-840 HU; and 7% mixed cystine plus calcium phosphate, 430-520 HU. HU values of all stone types ranged between 320 and 1365. There was a statistically significant relation between HU values of uric acid and non uric acid stones (p

  10. Kidney Stones in Children and Teens

    Science.gov (United States)

    ... Issues Listen Español Text Size Email Print Share Kidney Stones in Children and Teens Page Content Article ... teen girls having the highest incidence. Types of Kidney Stones There are many different types of kidney ...

  11. The Guy's stone score--grading the complexity of percutaneous nephrolithotomy procedures.

    Science.gov (United States)

    Thomas, Kay; Smith, Naomi C; Hegarty, Nicholas; Glass, Jonathan M

    2011-08-01

    To report the development and validation of a scoring system, the Guy's stone score, to grade the complexity of percutaneous nephrolithotomy (PCNL). Currently, no standardized method is available to predict the stone-free rate after PCNL. The Guy's stone score was developed through a combination of expert opinion, published data review, and iterative testing. It comprises 4 grades: grade I, solitary stone in mid/lower pole or solitary stone in the pelvis with simple anatomy; grade II, solitary stone in upper pole or multiple stones in a patient with simple anatomy or a solitary stone in a patient with abnormal anatomy; grade III, multiple stones in a patient with abnormal anatomy or stones in a caliceal diverticulum or partial staghorn calculus; grade IV, staghorn calculus or any stone in a patient with spina bifida or spinal injury. It was assessed for reproducibility using the kappa coefficient and validated on a prospective database of 100 PCNL procedures performed in a tertiary stone center. The complications were graded using the modified Clavien score. The clinical outcomes were recorded prospectively and assessed with multivariate analysis. The Guy's stone score was the only factor that significantly and independently predicted the stone-free rate (P = .01). It was found to be reproducible, with good inter-rater agreement (P = .81). None of the other factors tested, including stone burden, operating surgeon, patient weight, age, and comorbidity, correlated with the stone-free rate. The Guy's stone score accurately predicted the stone-free rate after PCNL. It was easy to use and reproducible. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Plausibiliteitsdocument STONE 2.0 (Globale verkenning van de plausibiliteit van het model STONE versie 2.0 voor de modellering van uit- en afspoeling van N en P).

    NARCIS (Netherlands)

    Overbeek, G.B.J.; Beusen, A.H.W.; Boers, P.C.M.; Born, van den G.J.; Groenendijk, P.; Grinsven, van J.J.M.; Kroon, T.; Meer, van der H.G.; Oosterom, H.P.; Puijenbroek, van P.J.T.M.; Roelsma, J.; Roest, C.W.J.; Rötter, R.; Tiktak, A.; Tol, van S.

    2002-01-01

    STONE is ontwikkeld om landsdekkend voor Nederland de effecten van bemesting en mestbeleid op de emissies van stikstof en fosfaat uit de landbouw naar grond- en oppervlaktewater te verkennen. De nadruk in de hier gerapporteerde plausibiliteitsstudie ligt op vaststelling van de geloofwaardigheid, het

  13. Plausibiliteitsdocument STONE 2.0.Globale verkenning van de plausibiliteit van het model STONE versie 2.0 voor de modellering van uit -en afspoeling van N en P

    NARCIS (Netherlands)

    Overbeek GBJ; Beusen AHW; Boers PCM; Born GJ van den; Groenendijk P; Grinsven JJM; Kroon T; Meer HG van der; Oosterom HP; Puijenbroek PJTM van; Roelsma J; Roest CJW; Rotter R; Tiktak A; Tol S van; LBG; CIM; LAE; LWD

    2002-01-01

    STONE is ontwikkeld om landsdekkend voor Nederland de effecten van bemesting en mestbeleid op de emissies van stikstof en fosfaat uit de landbouw naar grond- en oppervlaktewater te verkennen. De nadruk in de hier gerapporteerde plausibiliteitsstudie ligt op vaststelling van de geloofwaardigheid,

  14. Evidence Report: Risk of Renal Stone Formation

    Science.gov (United States)

    Sibonga, Jean D.; Pietrzyk, Robert

    2017-01-01

    The formation of renal stones poses an in-flight health risk of high severity, not only because of the impact of renal colic on human performance but also because of complications that could potentially lead to crew evacuation, such as hematuria, infection, hydronephrosis, and sepsis. Evidence for risk factors comes from urine analyses of crewmembers, documenting changes to the urinary environment that are conducive to increased saturation of stone-forming salts, which are the driving force for nucleation and growth of a stone nidus. Further, renal stones have been documented in astronauts after return to Earth and in one cosmonaut during flight. Biochemical analysis of urine specimens has provided indication of hypercalciuria and hyperuricemia, reduced urine volumes, and increased urine saturation of calcium oxalate and calcium phosphate. A major contributor to the risk for renal stone formation is bone atrophy with increased turnover of the bone minerals. Dietary and fluid intakes also play major roles in the risk because of the influence on urine pH (more acidic) and on volume (decreased). Historically, specific assessments on urine samples from some Skylab crewmembers indicated that calcium excretion increased early in flight, notable by day 10 of flight, and almost exceeded the upper threshold for normal excretion (300mg/day in males). Other crewmember data documented reduced intake of fluid and reduced intake of potassium, phosphorus, magnesium, and citrate (an inhibitor of calcium stone formation) in the diet. Hence, data from both short-duration and long-duration missions indicate that space travel induces risk factors for renal stone formation that continue to persist after flight; this risk has been documented by reported kidney stones in crewmembers.

  15. [Components of urinary crystallites in urine of uric acid stone formers and its relationship with formation of stones].

    Science.gov (United States)

    Huang, Zhi-jie; Tan, Jin; Ouyang, Jian-ming

    2010-09-01

    The components, zeta potential, morphology of nanocrystallites in urines of 10 uric acid stone formers as well as their relationship with the formation of uric acid stones were comparatively studied using X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, nanoparticle size analyzer, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The urine pH of uric acid stone formers was relatively low within the range of 4.8 to 5.7. The main constituent of urinary crystallites was uric acid. Their particle size distribution was highly uneven, ranging from several nanometers to several tens of micrometers, and obvious aggregation was observed. The zeta potential of urinary crystallites in ten lithogenic patients was -6.02 mV, which was higher than that in ten normal subjects (-10.1 mV). After drug therapies (potassium citrate was taken), the urine pH value of the uric acid stone formers increased to 6.5 or so, and at this pH value most of the uric acid had changed to urate. Since the solubility of urate increased greatly than uric acid, the risk of the formation of uric acid stone reduced. The results in this paper showed that there was a close relationship among stone components, urinary crystallites composition and urine pH.

  16. Famous Stone Patients and Their Disease

    Science.gov (United States)

    Moran, Michael E.

    2007-04-01

    The fact that stone patients have endured much throughout the ages and that prior to our current era, when the ultimate horror, "being cut for the stone" was the only alternative to the repeated episodes of colic, should be recalled from time to time. Urolithiasis has affected humanity throughout the ages and has been indiscriminate to those lives it touched. A full accounting of those who have suffered and recorded their agonies is beyond the scope of this investigation; however, even a partial accounting is valuable for present day physicians who care for those with stone disease. For the present work, the historical accounts of stone disease literature were scrutinized for individual sufferers who could be cross-referenced from other sources as legitimately afflicted by stones. Only those patients that could be documented and were (or are) well known were included, because the internet is now a verdant repository of thousands of "not so well knowns." Reliable historical data was found for a variety of persons from the pre-Christian era to the present, including those remembered as philosophers and scientists, physicians, clergy, leaders and rulers, entertainers, athletes and fictitious/Hollywood-type individuals. Verified accounts of famous stone formers were chosen for this paper, and are presented in chronological order. The list of urolithiasis sufferers presented here is undoubtedly incomplete, but it is not through lack of trying that they are missing. Most often, the suffering do so silently, and that is always allowed.

  17. Retroperitoneoscopy for treatment of renal and ureteral stones.

    Science.gov (United States)

    Soares, Rodrigo S; Romanelli, Pedro; Sandoval, Marcos A; Salim, Marcelo M; Tavora, Jose E; Abelha, David L

    2005-01-01

    To assess the efficacy of retroperitoneoscopy for treating stones in the renal pelvis and proximal ureter. In the period from August 2003 to August 2004, 35 retroperitoneoscopies for treatment of urinary stones were performed on 34 patients. Fifteen patients (42%) had stones in the renal pelvis, and in 2 cases, there were associated stones in the upper caliceal group. Twenty patients (58%) had ureteral stones, all of them located above the iliac vessel. Twenty-five patients (71%) had previously undergone at least one session of extracorporeal lithotripsy and 8 patients (26%) also underwent ureteroscopy to attempt to remove the stone. Eight patients underwent retroperitoneoscopy as a primary procedure. Stone size ranged from 0.5 to 6 cm with a mean of 2.1 cm. Retroperitoneoscopy was performed by lumbar approach with initial access conducted by open technique and creation of space by digital dissection. We used a 10-mm Hasson trocar for the optics, and 2 or 3 additional working ports placed under visualization. Following identification, the urinary tract was opened with a laparoscopic scalpel and the stone was removed intact. The urinary tract was closed with absorbable 4-0 suture and a Penrose drain was left in the retroperitoneum. In 17 patients (49%), a double-J stent was maintained postoperatively. Surgical time ranged from 60 to 260 minutes with a mean of 140 minutes. The mean hospital stay was 3 days (1-10 days). The mean length of retroperitoneal urinary drainage was 3 days (1-10 days). There were minor complications in 6 (17.6%) patients and 1 case of conversion due to technical difficulty. Thirty-three patients (94%) became stone free. Retroperitoneoscopy is an effective, low-morbidity alternative for treatment of urinary stones.

  18. Retroperitoneoscopy for treatment of renal and ureteral stones

    Directory of Open Access Journals (Sweden)

    Rodrigo S. Soares

    2005-04-01

    Full Text Available OBJECTIVE: To assess the efficacy of retroperitoneoscopy for treating stones in the renal pelvis and proximal ureter. MATERIALS AND METHODS: In the period from August 2003 to August 2004, 35 retroperitoneoscopies for treatment of urinary stones were performed on 34 patients. Fifteen patients (42% had stones in the renal pelvis, and in 2 cases, there were associated stones in the upper caliceal group. Twenty patients (58% had ureteral stones, all of them located above the iliac vessel. Twenty-five patients (71% had previously undergone at least one session of extracorporeal lithotripsy and 8 patients (26% also underwent ureteroscopy to attempt to remove the stone. Eight patients underwent retroperitoneoscopy as a primary procedure. Stone size ranged from 0.5 to 6 cm with a mean of 2.1 cm. RESULTS: Retroperitoneoscopy was performed by lumbar approach with initial access conducted by open technique and creation of space by digital dissection. We used a 10-mm Hasson trocar for the optics, and 2 or 3 additional working ports placed under visualization. Following identification, the urinary tract was opened with a laparoscopic scalpel and the stone was removed intact. The urinary tract was closed with absorbable 4-0 suture and a Penrose drain was left in the retroperitoneum. In 17 patients (49%, a double-J stent was maintained postoperatively. Surgical time ranged from 60 to 260 minutes with a mean of 140 minutes. The mean hospital stay was 3 days (1-10 days. The mean length of retroperitoneal urinary drainage was 3 days (1-10 days. There were minor complications in 6 (17.6% patients and 1 case of conversion due to technical difficulty. Thirty-three patients (94% became stone free. CONCLUSION: Retroperitoneoscopy is an effective, low-morbidity alternative for treatment of urinary stones.

  19. INCREASING DEMANDS FOR NATURAL STONES USAGE AROUND THE WORLD

    Directory of Open Access Journals (Sweden)

    HASAN ÜÇPIRTI

    1998-12-01

    Full Text Available Due to great demands in construction business, the stone industry has been growing very fast around the world. In fact, the technological iınproveınents on the ınachinery of marble and granite processing plant and quarry in recent years gives impulse to the stone business. According to studies reported� there are recognizable increments on both productions and constructions. Natural stones become driving forces in tl1e countries economy. In this study� so ın e statistical nuınbers for productions and consumption of natural stones will be presented in a base of countries that strongly involve in stone business. The importance of the econoınical impacts of natural stone on countries econoıny wiJI be emphasized. Then, the future of natural stones and its business will be discussed

  20. Unravelling ground stone life histories: the spatial organization of stone tools and human activities at LN Makriyalos, Greece:

    OpenAIRE

    Tsoraki, Christina

    2007-01-01

    Unlike previous studies of ground stone technology in the Greek Neolithic, this paper follows a more contextualised approach by looking at contexts of deposition of ground stone from Late Neolithic Makriyalos, Northern Greece. The patterns attested in the distribution of ground stone objects between domestic and communal areas will be discussed in terms of the spatial and social contexts of tool use, curation and deposition, contributing to wider discussions about the way acts of production, ...

  1. Stabilization of a three-dimensional limit cycle walking model through step-to-step ankle control.

    Science.gov (United States)

    Kim, Myunghee; Collins, Steven H

    2013-06-01

    Unilateral, below-knee amputation is associated with an increased risk of falls, which may be partially related to a loss of active ankle control. If ankle control can contribute significantly to maintaining balance, even in the presence of active foot placement, this might provide an opportunity to improve balance using robotic ankle-foot prostheses. We investigated ankle- and hip-based walking stabilization methods in a three-dimensional model of human gait that included ankle plantarflexion, ankle inversion-eversion, hip flexion-extension, and hip ad/abduction. We generated discrete feedback control laws (linear quadratic regulators) that altered nominal actuation parameters once per step. We used ankle push-off, lateral ankle stiffness and damping, fore-aft foot placement, lateral foot placement, or all of these as control inputs. We modeled environmental disturbances as random, bounded, unexpected changes in floor height, and defined balance performance as the maximum allowable disturbance value for which the model walked 500 steps without falling. Nominal walking motions were unstable, but were stabilized by all of the step-to-step control laws we tested. Surprisingly, step-by-step modulation of ankle push-off alone led to better balance performance (3.2% leg length) than lateral foot placement (1.2% leg length) for these control laws. These results suggest that appropriate control of robotic ankle-foot prosthesis push-off could make balancing during walking easier for individuals with amputation.

  2. Stone-free-rate after extracorporeal shockwave lithotripsy in the management of pediatric renal stones in lower pole and other locations - a comparative study

    International Nuclear Information System (INIS)

    Iqbal, N.; Muhammad, S.; Akhter, S.

    2016-01-01

    To determine a difference in the stone-free-rate among different renal locations in children after extracorporeal shockwave lithotripsy (ESWL). Study Design: A descriptive study. Place and Duration of Study: Urology Department, Shifa International Hospital, Islamabad, Pakistan, from January 2007 to June 2015. Methodology: The study included children who underwent ESWL, divided into three groups based on location of stones in kidney as group A (lower pole stones), group B (upper and mid pole stones) and group C (renal pelvis stone), respectively. ESWL was done by standard technique using Storz Modulith SLX lithotripter 3rd generation. Data was collected by chart review. SPSS version 16 was used for data analysis. Results: Among 76 children with mean age of 7.55 +-4.16 years, 55 (72.4%) were males whereas 21 (27.6%) were females. Mean stone size was 1.08 +-0.59 cm. There were 34, 17 and 25 cases in groups A, B and C, respectively. PostESWL stone-free-rate was 47% in lower pole stones, 70.58% in upper and mid pole stones, and 68% in renal pelvis stones. Hematuria was seen in one patient from each group, sepsis in two patients from each of the mid pole/upper pole and lower pole group, while Steinstrasse in one patient from each group. (author)

  3. ASSESSING PATHOLOGIES ON VILLAMAYOR STONE (SALAMANCA, SPAIN BY TERRESTRIAL LASER SCANNER INTENSITY DATA

    Directory of Open Access Journals (Sweden)

    J. García-Talegón

    2015-02-01

    Full Text Available This paper deals with the assessing of pathologies in façades using a variety of intensity data provided by different terrestrial laser scanner. In particular, a complex building built in the Villamayor Stone that is to be candidate as a Global Heritage Stone Resource has been chosen as study case. The Villamayor Stone were quarrying for the construction and ornamentation of monuments in Salamanca, declared World Heritage City by UNESCO in 1988. The objective of this paper is to assess the pathologies of Villamayor Stone and compare the results obtained through the laser techniques with the classical techniques of mapped pathologies (i.e. visual inspection. For that intensity data coming from laser scanners will be used as non-destructive techniques applied to the façades and several retired plaques (after of building restoration of Villamayor Stone with pathologies (fissures, scales, loss of matter, humidity/biological colonization carried to the laboratory. Subsequently it will perform different comparisons between the accuracy reached with the different sensors and a high precision model setup on laboratory which performs as “ground truth”. In particular, the following objectives will be pursued: i accuracy assessment of the results obtained in in situ and laboratory; ii an automation or semi-automation of the detection of pathologies in Villamayor Stone; iii discriminate the different types of Villamayor Stone used in the façades in function of the radiometric response; iv establish a methodology for detection and assessing of pathologies based on laser scanner intensity data applied to monuments and modern buildings built in Villamayor Stone.

  4. Accuracy of endoscopic intraoperative assessment of urologic stone size.

    Science.gov (United States)

    Patel, Nishant; Chew, Ben; Knudsen, Bodo; Lipkin, Michael; Wenzler, David; Sur, Roger L

    2014-05-01

    Endoscopic treatment of renal calculi relies on surgeon assessment of residual stone fragment size for either basket removal or for the passage of fragments postoperatively. We therefore sought to determine the accuracy of endoscopic assessment of renal calculi size. Between January and May 2013, five board-certified endourologists participated in an ex vivo artificial endoscopic simulation. A total of 10 stones (pebbles) were measured (mm) by nonparticipating urologist (N.D.P.) with electronic calibers and placed into separate labeled opaque test tubes to prevent visualization of the stones through the side of the tube. Endourologists were blinded to the actual size of the stones. A flexible digital ureteroscope with a 200-μm core sized laser fiber in the working channel as a size reference was placed through the ureteroscope into the test tube to estimate the stone size (mm). Accuracy was determined by obtaining the correlation coefficient (r) and constructing an Altman-Bland plot. Endourologists tended to overestimate actual stone size by a margin of 0.05 mm. The Pearson correlation coefficient was r=0.924, with a p-valuestones (stones (≥4 mm), r=0.911 vs r=0.666. Altman-bland plot analysis suggests that surgeons are able to accurately estimate stone size within a range of -1.8 to +1.9 mm. This ex vivo simulation study demonstrates that endoscopic assessment is reliable when assessing stone size. On average, there was a slight tendency to overestimate stone size by 0.05 mm. Most endourologists could visually estimate stone size within 2 mm of the actual size. These findings could be generalized to state that endourologists are accurately able to intraoperatively assess residual stone fragment size to guide decision making.

  5. Imaging-based logics for ornamental stone quality chart definition

    Science.gov (United States)

    Bonifazi, Giuseppe; Gargiulo, Aldo; Serranti, Silvia; Raspi, Costantino

    2007-02-01

    Ornamental stone products are commercially classified on the market according to several factors related both to intrinsic lythologic characteristics and to their visible pictorial attributes. Sometimes these latter aspects prevail in quality criteria definition and assessment. Pictorial attributes are in any case also influenced by the performed working actions and the utilized tools selected to realize the final stone manufactured product. Stone surface finishing is a critical task because it can contribute to enhance certain aesthetic features of the stone itself. The study was addressed to develop an innovative set of methodologies and techniques able to quantify the aesthetic quality level of stone products taking into account both the physical and the aesthetical characteristics of the stones. In particular, the degree of polishing of the stone surfaces and the presence of defects have been evaluated, applying digital image processing strategies. Morphological and color parameters have been extracted developing specific software architectures. Results showed as the proposed approaches allow to quantify the degree of polishing and to identify surface defects related to the intrinsic characteristics of the stone and/or the performed working actions.

  6. Stone-dwelling actinobacteria Blastococcus saxobsidens, Modestobacter marinus and Geodermatophilus obscurus proteogenomes

    KAUST Repository

    Sghaier, Haïtham

    2015-06-30

    The Geodermatophilaceae are unique model systems to study the ability to thrive on or within stones and their proteogenomes (referring to the whole protein arsenal encoded by the genome) could provide important insight into their adaptation mechanisms. Here we report the detailed comparative genome analysis of Blastococcus saxobsidens (Bs), Modestobacter marinus (Mm) and Geodermatophilus obscurus (Go) isolated respectively from the interior and the surface of calcarenite stones and from desert sandy soils. The genome-scale analysis of Bs, Mm and Go illustrates how adaptation to these niches can be achieved through various strategies including ‘molecular tinkering/opportunism’ as shown by the high proportion of lost, duplicated or horizontally transferred genes and ORFans. Using high-throughput discovery proteomics, the three proteomes under unstressed conditions were analyzed, highlighting the most abundant biomarkers and the main protein factors. Proteomic data corroborated previously demonstrated stone-related ecological distribution. For instance, these data showed starvation-inducible, biofilm-related and DNA-protection proteins as signatures of the microbes associated with the interior, surface and outside of stones, respectively.

  7. Stone-dwelling actinobacteria Blastococcus saxobsidens, Modestobacter marinus and Geodermatophilus obscurus proteogenomes

    KAUST Repository

    Sghaier, Haï tham; Hezbri, Karima; Ghodhbane-Gtari, Faten; Pujic, Petar; Sen, Arnab; Daffonchio, Daniele; Boudabous, Abdellatif; Tisa, Louis S; Klenk, Hans-Peter; Armengaud, Jean; Normand, Philippe; Gtari, Maher

    2015-01-01

    The Geodermatophilaceae are unique model systems to study the ability to thrive on or within stones and their proteogenomes (referring to the whole protein arsenal encoded by the genome) could provide important insight into their adaptation mechanisms. Here we report the detailed comparative genome analysis of Blastococcus saxobsidens (Bs), Modestobacter marinus (Mm) and Geodermatophilus obscurus (Go) isolated respectively from the interior and the surface of calcarenite stones and from desert sandy soils. The genome-scale analysis of Bs, Mm and Go illustrates how adaptation to these niches can be achieved through various strategies including ‘molecular tinkering/opportunism’ as shown by the high proportion of lost, duplicated or horizontally transferred genes and ORFans. Using high-throughput discovery proteomics, the three proteomes under unstressed conditions were analyzed, highlighting the most abundant biomarkers and the main protein factors. Proteomic data corroborated previously demonstrated stone-related ecological distribution. For instance, these data showed starvation-inducible, biofilm-related and DNA-protection proteins as signatures of the microbes associated with the interior, surface and outside of stones, respectively.

  8. Comparison of STONE, CROES and Guy's nephrolithometry scoring systems for predicting stone-free status and complication rates after percutaneous nephrolithotomy in obese patients.

    Science.gov (United States)

    Ozgor, Faruk; Yanaral, Fatih; Savun, Metin; Ozdemir, Harun; Sarilar, Omer; Binbay, Murat

    2017-07-29

    In this study, we aim to evaluate the accuracy of STONE (stone size, tract length, obstruction, number of involved calyces, and essence/stone density), Clinical Research Office of the Endourological Society (CROES), and Guy's nephrolithometry scoring systems (NSS) in obese patients. The charts of patients who underwent percutaneous nephrolithotomy (PNL) between June 2008 and June 2016 were retrospectively analyzed. Calculations of the STONE, CROES, and Guy's NSS were performed by a resident who was well informed regarding each NSS. Patients were classified under nine scores according to STONE, four grades according to CROES, and four grades according to Guy's NSS. In total, 248 obese patients were enrolled in the study. Stone size was significantly higher in patients without stone-free status (p = 0.001). In patients who were stone-free and those with residual stones, the mean STONE score was 9.71 and 9.23 (p = 0.160), CROES was 172 and 129 (p = 0.001), and Guy's NSS was 1.67 and 2.75 (p = 0.001). Multivariate regression analysis identified the CROES and Guy's NSS were independent factors for PNL success in obese patients (p = 0.01 and p = 0.01, respectively). The CROES and Guy's NSS showed good accuracy with PNL success (AUC = 0.777 and AUC = 0.844, respectively). None of the three NSS systems were statically associated with a complication rate (p = 0.23 for STONE, p = 0.14 for CROES, and p = 0.51 for Guy's NSS). Our study demonstrated that CROES and Guy's NSS were independent predictors of stone-free rate following PNL in obese patients. Our study also revealed that three of the NSSs were not useful for predicting PNL complications in obese patients.

  9. Computer aided detection of ureteral stones in thin slice computed tomography volumes using Convolutional Neural Networks.

    Science.gov (United States)

    Längkvist, Martin; Jendeberg, Johan; Thunberg, Per; Loutfi, Amy; Lidén, Mats

    2018-06-01

    Computed tomography (CT) is the method of choice for diagnosing ureteral stones - kidney stones that obstruct the ureter. The purpose of this study is to develop a computer aided detection (CAD) algorithm for identifying a ureteral stone in thin slice CT volumes. The challenge in CAD for urinary stones lies in the similarity in shape and intensity of stones with non-stone structures and how to efficiently deal with large high-resolution CT volumes. We address these challenges by using a Convolutional Neural Network (CNN) that works directly on the high resolution CT volumes. The method is evaluated on a large data base of 465 clinically acquired high-resolution CT volumes of the urinary tract with labeling of ureteral stones performed by a radiologist. The best model using 2.5D input data and anatomical information achieved a sensitivity of 100% and an average of 2.68 false-positives per patient on a test set of 88 scans. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Sonography as an initial study in patients with suspected ureteral stone

    International Nuclear Information System (INIS)

    Lee, Jae Gue; Lim, Joo Won; Ko, Young Tae; Lee, Dong Ho; Lee, Hye Won; Oh, Joo Hyeong; Yoon, Yup; Lee, Sun Ju

    1999-01-01

    To evaluate the usefulness of sonography as an initial study in patients with suspected ureteral stone. We have undertaken a prospective study for 106 patients with suspected ureteral stone during 15 months. All the patients subsequently underwent urography at a mean interval of 1.8 days after the abdominopelvic sonography. We had only a clinical impression at the sonography and didn't refer to the other study such as KUB. We observed the degree of hydronephrosis using a grading system by Ellenbogen et aland location and size of stone. Seventy four patients had ureteral stone disease. The sonographic findings of these 74 patients showed a stone with hydronephrosis in 61 patients, a stone without hydronephrosis in 9, only hydronephrosis without stone in 2, and unremarkable finding in 2. In 3 of the remaining 32 patients, sonography showed hydronephrosis without stone. Locations of stone were 9 patients of ureteropelvic junction(UPJ), 19 of proximal ureter, 30 of distal ureter, and 16 of ureterovesical junction(UVJ). The sensitivity of sonography for stone was 95% and the specificity was 100%. When a ureteral stone was present, ipsilateral hydronephrosis was detected in 85% of cases on sonography. When only hydronephrosis without stone was detected on sonography, a ureteral stone was diagnosed in 2(40%) of 5 patients. Mean discrepancy of stone size between sonography and KUB was 3.1mm and stone size on sonography was larger. Grade of hydronephrosis between sonography and urography was the same in 32(59%) of 54 patients, whose stones were not expelled until urography after sonography. Sonography could be used as an initial study in patients with suspected ureteral stone.

  11. COMORBIDITY OF KIDNEY STONES AND PYCHIATRIC DISEASE

    OpenAIRE

    Bilić, Vedran; Marčinko, Darko

    2010-01-01

    This paper describes a patient who is suffering from PTSD with elements of hypochondria, panic attacks and episodes of 0depression in comorbidity with kidney stones. Kidney stones provoked egzacerbation of psychiatric symptoms. Kidney stones and frustration about them have taken part of provoking factor, the last drop, which led to regression of otherwise precarious, but compensated patient’s mental functioning which resulted in development of psychiatric symptoms.

  12. Sarsen Stones of Stonehenge: How and by what route were the stones transported? What is the significance of their markings?

    Science.gov (United States)

    Hill, P A

    1961-04-21

    A route via Lockeridge and the Avon Valley, involving a slide down the chalk escarpment, is postulated for the sarsen stones of Stonehenge. The transportation problem would have been greatly simplified if the stones had been relayed from point to point over snow or slush during successive winters. Markings on the stones hitherto undescribed are interpreted.

  13. Treatment of upper urinary tract stones with extracorporeal shock wave lithotripsy (ESWL) Sonolith vision.

    Science.gov (United States)

    Nakamura, Kogenta; Tobiume, Motoi; Narushima, Masahiro; Yoshizawa, Takahiko; Nishikawa, Genya; Kato, Yoshiharu; Katsuda, Remi; Zennami, Kenji; Aoki, Shigeyuki; Yamada, Yoshiaki; Honda, Nobuaki; Sumitomo, Makoto

    2011-12-12

    The aim was to retrospectively assess the results of treatment of upper urinary tract stones with the Sonolith vision manufactured by EDAP, and purchased in 2004. The subjects were 226 Japanese patients who underwent extracorporeal shock wave lithotripsy (ESWL) alone as an initial treatment and could be followed up for at least 3 months, selected from 277 candidate patients who underwent this therapy between 2004 and 2006. Treatment effect was evaluated by kidney, ureter, and bladder X-ray or renal ultrasonography at 1 and 3 months after treatment. A stone-free status or status of stone fragmentation to 4 mm or smaller was considered to indicate effective treatment. At 3 months after treatment, the stone-free rate was 69.4% and the efficacy rate was 77.4% for renal stones, while these rates were 91.5 and 93.3%, respectively for ureteral stones. Assessment of treatment effect classified by the location of stones revealed a stone-free rate of 94.6% and an efficacy rate of 94.6% for lower ureteral stones (4.0 mm or smaller, 1 subject; 4.1-10.0 mm, 31 subjects; 10.1-20.0 mm, 5 subjects: number of treatment sessions, 1 or 2 sessions [mean: 1.03 sessions]). Complications of this therapy included renal subcapsular hematoma and pyelonephritis in 1 case each. ESWL with the Sonolith vision manufactured by EDAP produced a treatment effect equivalent to those achieved with other models of ESWL equipment. ESWL seems to be an effective first-line treatment also in patients who have lower ureteral stones 10 mm or larger but do not wish to undergo TUL, if measures such as suitable positioning of the patient during treatment are taken.

  14. Treatment of upper urinary tract stones with extracorporeal shock wave lithotripsy (ESWL Sonolith vision

    Directory of Open Access Journals (Sweden)

    Nakamura Kogenta

    2011-12-01

    Full Text Available Abstract Background The aim was to retrospectively assess the results of treatment of upper urinary tract stones with the Sonolith vision manufactured by EDAP, and purchased in 2004. Methods The subjects were 226 Japanese patients who underwent extracorporeal shock wave lithotripsy (ESWL alone as an initial treatment and could be followed up for at least 3 months, selected from 277 candidate patients who underwent this therapy between 2004 and 2006. Treatment effect was evaluated by kidney, ureter, and bladder X-ray or renal ultrasonography at 1 and 3 months after treatment. A stone-free status or status of stone fragmentation to 4 mm or smaller was considered to indicate effective treatment. Results At 3 months after treatment, the stone-free rate was 69.4% and the efficacy rate was 77.4% for renal stones, while these rates were 91.5 and 93.3%, respectively for ureteral stones. Assessment of treatment effect classified by the location of stones revealed a stone-free rate of 94.6% and an efficacy rate of 94.6% for lower ureteral stones (4.0 mm or smaller, 1 subject; 4.1-10.0 mm, 31 subjects; 10.1-20.0 mm, 5 subjects: number of treatment sessions, 1 or 2 sessions [mean: 1.03 sessions]. Complications of this therapy included renal subcapsular hematoma and pyelonephritis in 1 case each. Conclusions ESWL with the Sonolith vision manufactured by EDAP produced a treatment effect equivalent to those achieved with other models of ESWL equipment. ESWL seems to be an effective first-line treatment also in patients who have lower ureteral stones 10 mm or larger but do not wish to undergo TUL, if measures such as suitable positioning of the patient during treatment are taken.

  15. Measuring stone volume - three-dimensional software reconstruction or an ellipsoid algebra formula?

    Science.gov (United States)

    Finch, William; Johnston, Richard; Shaida, Nadeem; Winterbottom, Andrew; Wiseman, Oliver

    2014-04-01

    To determine the optimal method for assessing stone volume, and thus stone burden, by comparing the accuracy of scalene, oblate, and prolate ellipsoid volume equations with three-dimensional (3D)-reconstructed stone volume. Kidney stone volume may be helpful in predicting treatment outcome for renal stones. While the precise measurement of stone volume by 3D reconstruction can be accomplished using modern computer tomography (CT) scanning software, this technique is not available in all hospitals or with routine acute colic scanning protocols. Therefore, maximum diameters as measured by either X-ray or CT are used in the calculation of stone volume based on a scalene ellipsoid formula, as recommended by the European Association of Urology. In all, 100 stones with both X-ray and CT (1-2-mm slices) were reviewed. Complete and partial staghorn stones were excluded. Stone volume was calculated using software designed to measure tissue density of a certain range within a specified region of interest. Correlation coefficients among all measured outcomes were compared. Stone volumes were analysed to determine the average 'shape' of the stones. The maximum stone diameter on X-ray was 3-25 mm and on CT was 3-36 mm, with a reasonable correlation (r = 0.77). Smaller stones (15 mm towards scalene ellipsoids. There was no difference in stone shape by location within the kidney. As the average shape of renal stones changes with diameter, no single equation for estimating stone volume can be recommended. As the maximum diameter increases, calculated stone volume becomes less accurate, suggesting that larger stones have more asymmetric shapes. We recommend that research looking at stone clearance rates should use 3D-reconstructed stone volumes when available, followed by prolate, oblate, or scalene ellipsoid formulas depending on the maximum stone diameter. © 2013 The Authors. BJU International © 2013 BJU International.

  16. Complete supine percutaneous nephrolithotomy with GoPro®. Ten steps for success.

    Science.gov (United States)

    Vicentini, Fabio Carvalho; Dos Santos, Hugo Daniel Barone; Batagello, Carlos Alfredo; Amundson, Julia Rothe; Oliveira, Evaristo Peixoto; Marchini, Giovanni Scala; Srougi, Miguel; Nahas, Willian Carlos; Mazzucchi, Eduardo

    2018-03-15

    To show a video of a complete supine Percutaneous Nephrolithotomy (csPCNL) performed for the treatment of a staghorn calculus, from the surgeon's point of view. The procedure was recorded with a GoPro® camera, demonstrating the ten essential steps for a successful procedure. The patient was a 38 years-old woman with 2.4cm of left kidney lower pole stone burden who presented with 3 months of lumbar pain and recurrent urinary tract infections. She had a previous diagnosis of polycystic kidney disease and chronic renal failure stage 2. CT scan showed two 1.2cm stones in the lower pole (Guy's Stone Score 2). She had a previous ipsilateral double J insertion due to an obstructive pyelonephritis. The csPCNL was uneventful with a single access in the lower pole. The surgeon had a Full HD GoPro Hero 4 Session® camera mounted on his head, controlled by the surgical team with a remote control. All of the mains steps were recorded. Informed consent was obtained prior to the procedure. The surgical time was 90 minutes. Hemoglobin drop was 0.5g/dL. A post-operative CT scan was stone-free. The patient was discharged 36 hours after surgery. The camera worked properly and didn't cause pain or muscle discomfort to the surgeon. The quality of the recorded movie was excellent. GoPro® camera proved to be a very interesting tool to document surgeries without interfering with the procedure and with great educational potential. More studies should be conducted to evaluate the role of this equipment. Copyright® by the International Brazilian Journal of Urology.

  17. Introductory Overview of Stone Heritages in Japan

    Science.gov (United States)

    Kato, Hirokazu; Oikawa, Teruki; Fujita, Masayo; Yokoyama, Shunji

    2013-04-01

    As one contribution to 'Global Heritage Stone Resources' (GHSR), some stone heritages in Japan, which are nominated in the interim list, are briefly introduced. The geology of Japanese Islands where are the one of the most active areas in the history of the Earth, is very complicated. Therefore Japanese Islands consist of various kinds of minerals and rocks. Some of them were used to make stone implements and accessories. Japanese people also used to the best possible advantage to built tombstone, gate, pavement ,and the basement and wall of the large building such as temples, shrines, castles and modern buildings. 1. Stone Heritages of Pre-historical age: In the late Pleistocene and the early Holocene, ancient Japanese used obsidian cooled rapidly from rhyolitic magma.to make small implements and accessories. For example, Shirataki, Hokkaido (north island) is the largest place producing obsidian in Japan where Paleolithic people made arrowhead, knives and so on. Another example, Jade yielded in Itoigawa City, Japan Sea coast of central Japan, was made in the metamorphic rock about five hundred million years ago. Itoigawa area is only one place where jade is abundantly produced in Japan. Ancient people had been already collected and processed to ornaments although it is very hard and traded in wide area more than several thousand years ago. 2. Stone Heritages of Historical age: 2.1 Archaeological remains: In the Kofun (old mound) period (250 to 538 AD), stone burial chambers were used for old mounds to preserve against the putrefaction and to protect from the theft. For example, Ishibutai Kofun ("ishi" means "stone" and "butai" means "stage") in Nara old capital city, southwest Japan, is the largest known megalithic structure made of granite in Japan. 2.2 Stone walls of some typical castles Stones used is because of not only the rich reserves of rocks but also restriction of transportation. Osaka (second biggest city) castle, are composed of Cretaceous granite

  18. Comparative Study between Digital Tomosynthesis and Endoscopic Retrograde Cholangio pancreatography for the Evaluation of Common Bile Duct Stones: Focus on Detection and Stone Conspicuity

    International Nuclear Information System (INIS)

    Huh, Ji Mi; Baek, Seung Yon; Hwang, Yun Mi; Lee, Jeong Kyong; Kim, Yoo Kyung; Yi, Sun Young

    2011-01-01

    To compare digital tomosynthesis with endoscopic retrograde cholangiopancreatography (ERCP) for the evaluation of common bile duct (CBD) stones as a complementary diagnostic tool. Ninety six consecutive patients clinically suspected of having CBD stones underwent ERCP and digital tomosynthesis over 22 months, from December, 2008 to May, 2010. Fourteen patients were excluded. Therefore 82 patients were included in this study. The images were retrospectively reviewed to compare the results with the final analysis based on the consensus of two abdominal radiologists. An evaluation of the presence of CBD stones was followed by a determination of the margins for the stones, scored with a five-point conspicuity scale. Among the 82 patients, 54 collectively had 89 CBD stones and 28 had no stones. The sensitivity and specificity for the detection of CBD stones were 91.0% and 80.6% for ERCP, 92.1% and 93.5% for digital tomosynthesis, respectively. The average score was 3.29 for ERCP and 3.89 for digital tomosynthesis in 77 similar detected stones. Digital tomosynthesis demonstrated significantly better conspicuity than ERCP (p = 0.001). Digital tomosynthesis is an effective and complementary diagnostic method for the evaluation of CBD stones.

  19. Strength Improvement of Clay Soil by Using Stone Powder

    Directory of Open Access Journals (Sweden)

    Ahmed Sameer Abdulrasool

    2015-05-01

    Full Text Available Soil stabilization with stone powder is a good solution for the construction of subgrade for road way and railway lines, especially under the platforms and mostly in transition zones between embankments and rigid structures, where the mechanical properties of supporting soils are very influential. Stone powder often has a unique composition which justifies the need for research to study the feasibility of using this stone powder type for ground improvement applications. This paper presents results from a comprehensive laboratory study carried out to investigate the feasibility of using stone powder for improvement of engineering properties of clays. The stone powder contains bassanite (CaSO4. ½ H2O, and Calcite (CaCO3. Three percentages are used for stone powder (1%, 3% and 5% by dry weight of clay. Several tests are made to investigate the soil behavior after adding the stone powder (Atterberg limits, Standard Proctor density, Grain size distribution, Specific gravity, Unconfined Compressive test, and California bearing ratio test. Unconfined Compressive tests conducted at different curing. The samples are tested under both soaked and unsoaked condition. Chemical tests and X-ray diffraction analyses are also carried out. Stone powder reacts with clay producing decreasing in plasticity and The curves of grain size distribution are shifted to the coarse side as the stone powder percentage increase; the soil becomes more granular, and also with higher strength.

  20. Prevalence of renal uric acid stones in the adult.

    Science.gov (United States)

    Trinchieri, Alberto; Montanari, Emanuele

    2017-12-01

    The aim of this study was to estimate uric acid renal stone prevalence rates of adults in different countries of the world. PubMed was searched for papers dealing with "urinary calculi and prevalence or composition" for the period from January 1996 to June 2016. Alternative searches were made to collect further information on specific topics. The prevalence rate of uric acid stones was computed by the general renal stone prevalence rate and the frequency of uric acid stones in each country. After the initial search, 2180 papers were extracted. Out of them, 79 papers were selected after the reading of the titles and of the abstracts. For ten countries, papers relating to both the renal stone prevalence in the general population and the frequency of uric stones were available. Additional search produced 13 papers that completed information on 11 more countries in 5 continents. Estimated prevalence rate of uric acid stones was >0.75% in Thailand, Pakistan, Saudi Arabia, Iran, South Africa (white population), United States and Australia; ranged 0.50-0.75% in Turkey, Israel, Italy, India (Southern), Spain, Taiwan, Germany, Brazil; and uric acid stone formation. A hot and dry climate increases fluid losses reducing urinary volume and urinary pH. A diet rich in meat protein causes low urinary pH and increased uric acid excretion. On the other hand, uric acid stone formation is frequently associated with obesity, metabolic syndrome and diabetes type 2 that are linked to dietary energy excess mainly from carbohydrate and saturated fat and also present with low urine pH values. An epidemic of uric acid stone formation could be if current nutritional trends will be maintained both in developed countries and in developing countries and the areas of greater climatic risk for the formation of uric acid stones will enlarge as result of the "global warming".

  1. A comparative study of mud-like and coralliform calcium carbonate gallbladder stones.

    Science.gov (United States)

    Ma, Rui-Hong; Luo, Xiao-Bing; Wang, Xiao-Feng; Qiao, Tie; Huang, Hai-Yi; Zhong, Hai-Qiang

    2017-07-01

    To gain insight to underlying mechanism of the formation of calcium carbonate (CaCO 3 ) gallbladder stones, we did comparative study of stones with mud appearance and those with coralliform appearance. A total of 93 gallbladder stones with mud appearance and 50 stones with coralliform appearance were analyzed. The appearance, color, texture, and the detection of Clonorchis sinensis eggs by microscopic examination were compared between the two groups. Then, the material compositions of stones were analyzed using Fourier Transform Infrared spectroscopy and the spectrogram characteristics were compared. Moreover, microstructure characteristics of the two kinds of stones were observed and compared with Scanning Electron Microscopy. Mud-like gallbladder stones were mainly earthy yellow or brown with brittle or soft texture, while coralliform stones were mainly black with extremely hard texture, the differences between the two groups was significant (p mud-like gallbladder stones were CaCO 3 stones, and mainly aragonite; while all of the coralliform stones were CaCO 3 stones, and mainly calcite (p mud-like CaCO 3 stones was lower than that in coralliform CaCO 3 stones (p Mud-like CaCO 3 stones mainly happened to patients with cystic duct obstruction. Clonorchis sinensis infection was mainly associated with coralliform (calcite) CaCO 3 stones. Cystic duct obstruction was mainly associated with mud-like (aragonite) CaCO 3 stones. © 2017 Wiley Periodicals, Inc.

  2. [Fast determination of contents of nutrients and stone powder in compound fertilizer using near infrared diffuse reflectance spectroscopy].

    Science.gov (United States)

    Guo, Zheng; Yuan, Hong-Fu; Zhang, Xian; Song, Chun-Feng; Li, Xiao-Yu; Xie, Jin-Chun

    2011-06-01

    In the present paper, a new approach to fast determination of contents of nutrients, including total nitrogen content (N), P2O5 content (P) and K2O content (K), and of stone powder content in compound fertilizer composed of urea, ammonium dihydrogen phosphate, potassium chloride and stone powder was proposed using near infrared diffuse reflectance spectroscopy. PLS models of N, P and stone powder content were built with the SEP values of 0.8, 0.8 and 1.4 respectively. The information on which stone powder content model was built is the spectrum of crystal water existing in stone powder. K content was calculated using other ingredientcontents by normalization principle with a SEP value of 1.5. Although the SEP values are a little larger than the reproducibility errors of the GB/T methods which are conventional methods, the new method can be accepted by situ quality control in the production process of compound fertilizer.

  3. Journey of a cystinuric patient with a long-term follow-up from a medical stone clinic: necessity to be SaFER (stone and fragments entirely removed).

    Science.gov (United States)

    Moore, Sacha L; Somani, Bhaskar K; Cook, Paul

    2018-04-25

    There is a lack of studies looking at the longitudinal follow-up of patients with cystine stones. We wanted to assess the journey of cystinuric patients through our specialist metabolic stone clinic to improve the understanding of episodes, interventions and current outcomes in this patient cohort. After ethical approval, all patients who attended our metabolic stone clinic from 1994 to 2014 with at least one cystine stone episode were included in our study. Data were retrospectively analysed for patient demographics, stone episodes or intervention, clinical parameters and patient compliance. Over a period of 21 years, 16 patients with a median age of 15.5 years underwent a mean follow-up of 8.6 years (1-21 years). The mean number of surgical interventions was 3.1 (1-8/patient), but patients who were stone free after their first treatment had lower recurrences (p = 0.91) and lower number of interventions during their follow-up (2.7/patient, compared to those who were not stone free at 4/patient). During their follow-up period, patients with stone episodes (r 2  = 0.169). It was also noted that patients who began early medical management remained stone free during follow-up compared to those who had medical management after ≥ 2 stone episodes, of whom all had a recurrent episode. Our long-term longitudinal study of cystine stone formers highlights that patients who are stone free and receive early metabolic stone screening and medical management after their initial presentation have the lowest recurrence rates and tend to preserve their renal function. Hence, prompt referral for metabolic assessment, and the stone and fragments entirely removed (SaFER) principles are key to preventing stone episodes and improving long-term function.

  4. Impact of stone density on outcomes in percutaneous nephrolithotomy (PCNL)

    DEFF Research Database (Denmark)

    Anastasiadis, Anastasios; Onal, Bulent; Modi, Pranjal

    2013-01-01

    were assigned to a low stone density [LSD, ≤ 1000 Hounsfield units (HU)] or high stone density (HSD, > 1000 HU) group based on the radiological density of the primary renal stone. Preoperative characteristics and outcomes were compared in the two groups. Results. Retreatment for residual stones...... was more frequent in the LSD group. The overall stone-free rate achieved was higher in the HSD group (79.3% vs 74.8%, p = 0.113). By univariate regression analysis, the probability of achieving a stone-free outcome peaked at approximately 1250 HU. Below or above this density resulted in lower treatment...

  5. Efficacy of surgical techniques and factors affecting residual stone rate in the treatment of kidney stones.

    Science.gov (United States)

    Aydemir, Hüseyin; Budak, Salih; Kumsar, Şükrü; Köse, Osman; Sağlam, Hasan Salih; Adsan, Öztuğ

    2014-09-01

    In this study, we aimed to evaluate, the efficacy of surgical methods and the factors affecting the residual stone rate by scrutinizing retrospectively the patients who had undergone renal stone surgery. Records of 109 cases of kidney stones who had been surgically treated between January 2010, and July 2013 were reviewed. Patients were divided into three groups in terms of surgical treatment; open stone surgery, percutaneous nephrolithotomy (PNL) and retrograde intrarenal surgery (RIRS). Patients' history, physical examination, biochemical and radiological images and operative and postoperative data were recorded. The patients had undergone PNL (n=74; 67.9%), RIRS (n=22;20.2%), and open renal surgery (n=13; 11.9%). The mean and median ages of the patients were 46±9, 41 (21-75) and, 42 (23-67) years, respectively. The mean stone burden was 2.6±0.7 cm(2) in the PNL, 1.4±0.1 cm(2) in the RIRS, and 3.1±0.9 cm(2) in the open surgery groups. The mean operative times were 126±24 min in the PNL group, 72±12 min in the RIRS group and 82±22 min in the open surgery group. The duration of hospitalisation was 3.1±0.2 days, 1.2±0.3 days and 3.4±1.1 days respectively. While the RIRS group did not need blood transfusion, in the PNL group blood transfusions were given in the PNL (n=18), and open surgery (n=2) groups. Residual stones were detected in the PNL (n=22), open surgery (n=2), and RIRS (n=5) groups. PNL and RIRS have been seen as safe and effective methods in our self application too. However, it should not be forgotten that as a basical method, open surgery may be needed in cases of necessity.

  6. Accurately Diagnosing Uric Acid Stones from Conventional Computerized Tomography Imaging: Development and Preliminary Assessment of a Pixel Mapping Software.

    Science.gov (United States)

    Ganesan, Vishnu; De, Shubha; Shkumat, Nicholas; Marchini, Giovanni; Monga, Manoj

    2018-02-01

    Preoperative determination of uric acid stones from computerized tomography imaging would be of tremendous clinical use. We sought to design a software algorithm that could apply data from noncontrast computerized tomography to predict the presence of uric acid stones. Patients with pure uric acid and calcium oxalate stones were identified from our stone registry. Only stones greater than 4 mm which were clearly traceable from initial computerized tomography to final composition were included in analysis. A semiautomated computer algorithm was used to process image data. Average and maximum HU, eccentricity (deviation from a circle) and kurtosis (peakedness vs flatness) were automatically generated. These parameters were examined in several mathematical models to predict the presence of uric acid stones. A total of 100 patients, of whom 52 had calcium oxalate and 48 had uric acid stones, were included in the final analysis. Uric acid stones were significantly larger (12.2 vs 9.0 mm, p = 0.03) but calcium oxalate stones had higher mean attenuation (457 vs 315 HU, p = 0.001) and maximum attenuation (918 vs 553 HU, p uric acid stones. A combination of stone size, attenuation intensity and attenuation pattern from conventional computerized tomography can distinguish uric acid stones from calcium oxalate stones with high sensitivity and specificity. Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  7. Two-step two-stage fission gas release model

    International Nuclear Information System (INIS)

    Kim, Yong-soo; Lee, Chan-bock

    2006-01-01

    Based on the recent theoretical model, two-step two-stage model is developed which incorporates two stage diffusion processes, grain lattice and grain boundary diffusion, coupled with the two step burn-up factor in the low and high burn-up regime. FRAPCON-3 code and its in-pile data sets have been used for the benchmarking and validation of this model. Results reveals that its prediction is in better agreement with the experimental measurements than that by any model contained in the FRAPCON-3 code such as ANS 5.4, modified ANS5.4, and Forsberg-Massih model over whole burn-up range up to 70,000 MWd/MTU. (author)

  8. In vitro head-to-head comparison of the durability, versatility and efficacy of the NGage and novel Dakota stone retrieval baskets.

    Science.gov (United States)

    Bechis, Seth K; Abbott, Joel E; Sur, Roger L

    2017-12-01

    To compare head to head two end-engaging nitinol stone retrieval devices available to urologists, in terms of durability, versatility and efficacy. For durability testing, 30 NGage and Dakota baskets were cycled 20 times between grasping and releasing synthetic stone models and evaluated for damage or device failure. For versatility and efficacy testing, baskets were assessed in their ability to capture and release stone models from 1 to 11 mm. Each stone was raised above the capture site and the basket was opened to passively release the stone. If the stone did not release, the basket handle was shaken and the OpenSure feature employed if needed. Manual release was used as a last resort. Durability-the Cook NGage demonstrated a statistically significant increased rate of visible device breakdown (P=0.0046) in 8 of 30 (26.7%) devices vs. 0 of 30 Dakota devices, with mean damage at 13.5 cycles. Versatility and efficacy-both 8 mm baskets successfully captured stones from 1-8 mm. The Dakota more effectively released 7-8 mm stones (PDakota. For 11 mm baskets, the Dakota released all stones up to 10 mm with simple opening, while the NGage released 10 of 15 (67%) of 9 mm stones and 1 of 15 (7%) of 10 mm stones by simple opening. For 11 mm stones, the Dakota captured 100% whereas NGage could not capture any. Both baskets showed similar durability characteristics. The Dakota basket more effectively captured and released stones over 7 mm, as compared to the NGage basket. The OpenSure aspect conferred an advantage in handling and release of larger stones. These in vitro results demonstrate potential versatility, durability and efficacy of the Dakota basket.

  9. A quick in-situ estimating method for grading stone products as radiation protection standard of building materials

    International Nuclear Information System (INIS)

    Nanping, Wang; Shengli, Hou; Yexun, Chen

    2002-01-01

    Natural stone is word-widely used as building and decorating material, which is made of marble, granite or other kinds of rocks. Normally they are cut into rectangle with 20 mm thickness. In order to grade small size stone plank as radioactive protection standard (China Standard GB6566-2001), a quick in-situ technique and a special kind of portable -ray detector is developed. The detector is made of NaI (Tl) ( 30x50mm) with a shield (Model ZDD3901, China Patent No. 992080045). The difference modeling was established for small-size stone planks grading. About 96.3% stone plank samples which size are more than 300x300x20 mm could be determined radiation levels by in-situ techniques, by which the grading results (A, B or C) are coincided with quantity analysis in lab

  10. A quick in-situ estimating method for grading stone products as radiation protection standard of building materials

    Energy Technology Data Exchange (ETDEWEB)

    Nanping, Wang; Shengli, Hou; Yexun, Chen [China Univ. of Geosciences, Bijing (China)

    2002-07-01

    Natural stone is word-widely used as building and decorating material, which is made of marble, granite or other kinds of rocks. Normally they are cut into rectangle with 20 mm thickness. In order to grade small size stone plank as radioactive protection standard (China Standard GB6566-2001), a quick in-situ technique and a special kind of portable -ray detector is developed. The detector is made of NaI (Tl) ( 30x50mm) with a shield (Model ZDD3901, China Patent No. 992080045). The difference modeling was established for small-size stone planks grading. About 96.3% stone plank samples which size are more than 300x300x20 mm could be determined radiation levels by in-situ techniques, by which the grading results (A, B or C) are coincided with quantity analysis in lab.

  11. Stone Soup: The Teacher Leader's Contribution

    Science.gov (United States)

    Bambrick-Santoyo, Paul

    2013-01-01

    In the tale of "Stone Soup," a stranger vows to make soup for everyone in a village using only a stone--and convinces everyone in town to throw an ingredient into the stewpot. Schools that need to improve teacher practice quickly can also make stone soup, the author says, by harnessing the power of well-prepared teacher leaders to…

  12. A comparison of genetic connectivity in two deep sea corals to examine whether seamounts are isolated islands or stepping stones for dispersal

    Science.gov (United States)

    Miller, Karen J.; Gunasekera, Rasanthi M.

    2017-04-01

    Ecological processes in the deep sea are poorly understood due to the logistical constraints of sampling thousands of metres below the ocean’s surface and remote from most land masses. Under such circumstances, genetic data provides unparalleled insight into biological and ecological relationships. We use microsatellite DNA to compare the population structure, reproductive mode and dispersal capacity in two deep sea corals from seamounts in the Southern Ocean. The solitary coral Desmophyllum dianthus has widespread dispersal consistent with its global distribution and resilience to disturbance. In contrast, for the matrix-forming colonial coral Solenosmilia variabilis asexual reproduction is important and the dispersal of sexually produced larvae is negligible, resulting in isolated populations. Interestingly, despite the recognised impacts of fishing on seamount communities, genetic diversity on fished and unfished seamounts was similar for both species, suggesting that evolutionary resilience remains despite reductions in biomass. Our results provide empirical evidence that a group of seamounts can function either as isolated islands or stepping stones for dispersal for different taxa. Furthermore different strategies will be required to protect the two sympatric corals and consequently the recently declared marine reserves in this region may function as a network for D. dianthus, but not for S. variabilis.

  13. Stability of Reshaping Breakwaters with Special Reference to Stone Durability

    DEFF Research Database (Denmark)

    Frigaard, Peter; Hald, Tue; Burcharth, H. F.

    1996-01-01

    inherently cause some breakage and abrasion of the individual stones and thereby also reduced stability. In order to avoid excessive abrasion a high stone quality is demanded or larger stones must be applied when constructed. To allow the designer to account for abrasion and armour stone breakage due...

  14. EVALUATION OF CONSISTENCY AND SETTING TIME OF IRANIAN DENTAL STONES

    Directory of Open Access Journals (Sweden)

    F GOL BIDI

    2000-09-01

    Full Text Available Introduction. Dental stones are widely used in dentistry and the success or failure of many dental treatments depend on the accuracy of these gypsums. The purpose of this study was the evaluation of Iranian dental stones and comparison between Iranian and foreign ones. In this investigation, consistency and setting time were compared between Pars Dendn, Almas and Hinrizit stones. The latter is accepted by ADA (American Dental Association. Consistency and setting time are 2 of 5 properties that are necessitated by both ADA specification No. 25 and Iranian Standard Organization specification No. 2569 for evaluation of dental stones. Methods. In this study, the number and preparation of specimens and test conditions were done according to the ADA specification No. 25 and all the measurements were done with vicat apparatus. Results. The results of this study showed that the standard consistency of Almas stone was obtained by 42ml water and 100gr powder and the setting time of this stone was 11±0.03 min. Which was with in the limits of ADA specification (12±4 min. The standard consistency of Pars Dandan stone was obrianed by 31ml water and 100 gr powder, but the setting time of this stone was 5± 0.16 min which was nt within the limits of ADA specification. Discussion: Comparison of Iranian and Hinrizit stones properties showed that two probable problems of Iranian stones are:1- Unhemogrnousity of Iranian stoned powder was caused by uncontrolled temperature, pressure and humidity in the production process of stone. 2- Impurities such as sodium chloride was responsible fo shortening of Pars Dendens setting time.

  15. [Usefullness of the StoneBreaker lithotripter for percutaneous nephrolithotomy].

    Science.gov (United States)

    del Peso, Almudena Coloma; González, Inmaculada Fernández; Gálvez, Milagros Jiménez; Abad, Pablo Garrido; Fajardo, Gloria Bocardo; Fernández, Luis Miguel Herranz; Arjona, Manuel Fernández; Torres, Lorenzo Herrero; Sanz, Ignacio Pereira

    2008-01-01

    Throughout the history, many devices have been used for breaking urinary tract stones. StoneBreaker (LMA Urology, Gland, Switzerland) is a second generation of intracorporeal lithotripter, pneumatic and portable, which adds several new advantages, like effectiveness in stone fragmentation and easy handling, very useful during percutaneous lithotripsy. We report the case of a 40 year-old male patient, with a left kidney pyelic lithiasis, who was treated by percutaneous lithotripsy, under general anaesthesia, with StoneBreaker (LMA Urology, Gland, Switzerland) as lithotripter. StoneBreaker (LMA Urology, Gland, Switzerland) is a lithotripter usable with rigid and semirigid ureteroscopes, much more powerful than its predecessors. It is able to decrease the number of shocks necessary for stone fragmentation, without bigger tissue reaction. It also has a more comfortable design due to the absence of connections, and its power by replaceable carbon dioxide cartridges.

  16. Uric acid stones increase the risk of chronic kidney disease.

    Science.gov (United States)

    Li, Ching-Chia; Chien, Tsu-Ming; Wu, Wen-Jeng; Huang, Chun-Nung; Chou, Yii-Her

    2018-02-28

    The aim of this study was to compare the clinical characteristics of uric acid stones and their potential risk for chronic kidney disease (CKD). A total of 401 patients (196 with uric acid stone and 205 without) were enrolled from our database of patients with urolithiasis. We analyzed the clinical demographic features, stone location, urine chemistries, and renal function. There was a significant difference (p uric acid group. Patients with uric acid stones had much lower pH of urine (p uric acid level (p = 0.002). Notably, those with uric acid stones had worse eGFR than those with non-uric acid stones. Multivariate analysis confirmed that age over 60 years (ORs = 9.19; 95% CI 3.5-24.3), female sex (ORs = 4.01; 95% CI 1.8-9.0), hyperuricemia (ORs = 8.47; 95% CI 1.6-43.5), and uric acid stone (OR = 2.86; 95% CI 1.2-6.7) were the independent predictors of poor prognoses in CKD. Therefore, an association exists between uric acid stones and higher prevalence of CKD. Patients with uric acid stones may need close monitoring of renal function during follow-up.

  17. Technique and value of three dimensional reconstruction of stones in the renal pelvis using spiral CT

    International Nuclear Information System (INIS)

    Fink, B.K.; Fink, U.; Pentenrieder, M.; Kohz, P.; Englmeier, H.K.; Schmeller, N.

    1994-01-01

    5 patients with staghorn calculi in the renal pelvis were examined by spiral CT. From the raw data three dimensional reconstructions of the stones were obtained. In all patients it was possible to compare the three dimensional model with the stone following performance of percutaneous lithopaxy and endoscopic removal of the fragments. In all cases the three dimensional reconstruction provided a realistic image of the stones and was of practical value for the urologist for preoperative diagnosis and intraoperative control. (orig.) [de

  18. Association between dental pulp stones and calcifying nanoparticles.

    Science.gov (United States)

    Zeng, Jinfeng; Yang, Fang; Zhang, Wei; Gong, Qimei; Du, Yu; Ling, Junqi

    2011-01-07

    The etiology of dental pulp stones, one type of extraskeletal calcification disease, remains elusive to date. Calcifying nanoparticles (CNPs), formerly referred to as nanobacteria, were reported to be one etiological factor in a number of extraskeletal calcification diseases. We hypothesized that CNPs are involved in the calcification of the dental pulp tissue, and therefore investigated the link between CNPs and dental pulp stones. Sixty-five freshly collected dental pulp stones, each from a different patient, were analyzed. Thirteen of the pulp stones were examined for the existence of CNPs in situ by immunohistochemical staining (IHS), indirect immunofluorescence staining (IIFS), and transmission electron microscope (TEM). The remaining 52 pulp stones were used for isolation and cultivation of CNPs; the cultured CNPs were identified and confirmed via their shape and growth characteristics. Among the dental pulp stones examined in situ, 84.6% of the tissue samples staines positive for CNPs antigen by IHS; the corresponding rate by IIFS was 92.3 %. In 88.2% of the cultured samples, CNPs were isolated and cultivated successfully. The CNPs were visible under TEM as 200-400 nm diameter spherical particles surrounded by a compact crust. CNPs could be detected and isolated from a high percentage of dental pulp stones, suggesting that CNPs might play an important role in the calcification of dental pulp.

  19. Accuracy of stone casts obtained by different impression materials

    Directory of Open Access Journals (Sweden)

    Adriana Cláudia Lapria Faria

    2008-12-01

    Full Text Available Several impression materials are available in the Brazilian marketplace to be used in oral rehabilitation. The aim of this study was to compare the accuracy of different impression materials used for fixed partial dentures following the manufacturers' instructions. A master model representing a partially edentulous mandibular right hemi-arch segment whose teeth were prepared to receive full crowns was used. Custom trays were prepared with auto-polymerizing acrylic resin and impressions were performed with a dental surveyor, standardizing the path of insertion and removal of the tray. Alginate and elastomeric materials were used and stone casts were obtained after the impressions. For the silicones, impression techniques were also compared. To determine the impression materials' accuracy, digital photographs of the master model and of the stone casts were taken and the discrepancies between them were measured. The data were subjected to analysis of variance and Duncan's complementary test. Polyether and addition silicone following the single-phase technique were statistically different from alginate, condensation silicone and addition silicone following the double-mix technique (p .05 to alginate and addition silicone following the double-mix technique, but different from polysulfide. The results led to the conclusion that different impression materials and techniques influenced the stone casts' accuracy in a way that polyether, polysulfide and addition silicone following the single-phase technique were more accurate than the other materials.

  20. [The effiectiveness of extracorporeal shock wave lithotripsy in treating proxima ureteral stones].

    Science.gov (United States)

    Kogan, M I; Belousov, I I; Yassine, A M

    2017-10-01

    Extracorporeal shock wave lithotripsy (ESWL) has proven efficacy in the treatment of proximal ureteral stones. The research to date has not been able to establish real time to spontaneous stone clearance after ESWL and the appropriateness and effectiveness of -blockers in stimulating residual stone clearance after ESWL. To conduct a comprehensive assessment of the effectiveness of ESWL in treating proximal ureteral stones and determine the appropriateness of using -blockers to stimulate residual stone clearance. ESWL was performed in 40 patients with X-ray positive proximal ureteral stones. Before ESWL and at 3 months after the treatment all patients underwent multispiral computed tomography. ESWL was considered successful if there was a complete clearance of the stones with no residual fragments on the control MSCT. If a residual ureteral stone was found at 3 months after ESWL, a 2-week course of silodosin was administered. Complete stone clearance was achieved in 37.5% of patients. Silodosin therapy for residual stones resulted in stone clearance in 68.4% of cases. Taken together, ESWL monotherapy and additional 3 months of lithokinetic therapy resulted in stone clearance in 70.0% of patients. The remaining patients underwent contact ureteral lithotripsy. Spontaneous stone passage after ESWL for proximal ureteral stones occurs not in all patients. Most commonly it occurred during the first three weeks after ESWL, and thereafter stone passage was not observed. In half of the patients with residual stones they were asymptomatic. The effectiveness of ESWL as a monotherapy for ureteral stones greater than 15 mm is incomplete. Adding silodosin during the long-term post ESWL period improves the passage of asymptomatic residual stones in 2/3 of patients, which makes its use promising.

  1. Comparison of Model Reliabilities from Single-Step and Bivariate Blending Methods

    DEFF Research Database (Denmark)

    Taskinen, Matti; Mäntysaari, Esa; Lidauer, Martin

    2013-01-01

    Model based reliabilities in genetic evaluation are compared between three methods: animal model BLUP, single-step BLUP, and bivariate blending after genomic BLUP. The original bivariate blending is revised in this work to better account animal models. The study data is extracted from...... be calculated. Model reliabilities by the single-step and the bivariate blending methods were higher than by animal model due to genomic information. Compared to the single-step method, the bivariate blending method reliability estimates were, in general, lower. Computationally bivariate blending method was......, on the other hand, lighter than the single-step method....

  2. Crushed Stone Operations

    Data.gov (United States)

    Department of Homeland Security — This map layer includes crushed stone operations in the United States. These data were obtained from information reported voluntarily to the USGS by the aggregate...

  3. Approach to Residual Kidney Stone Fragments After Shock Wave Therapy

    Directory of Open Access Journals (Sweden)

    Tumay Ižpekci

    2014-04-01

    Full Text Available For kidney stones up to 2 cm in diameter shock wave therapy (SDT is safely applied and kidney stones smaller than 5mm remaining in the kidney after treatment are regarded as clinically insignificant. Management of this condition is still controversial among clinicians. These stones in the kidney may continue to persist without any clinical symptoms or begin to cause clinical signs. In the event that the clinical symptoms are present, it requires detailed urological examination and treatment. The aim in the surgical treatment of urinary tract stones is completely stone clearance but in stones that are not infected, not causing urinary tract obstruction and without clinical symptoms medical treatment is also beneficial fort he prevention of growth and recurrence. In addition, surgical intervention is also possible for the residual stone fragments which become symptomatic during follow-up.

  4. Factors affecting lower calyceal stone clearance after Extracorporeal shock wave lithotripsy

    Directory of Open Access Journals (Sweden)

    S. Azab

    2013-03-01

    Conclusions: There is no statistically significant effect of stone size, anatomy of the lower calyx and BMI on stone clearance after ESWL of lower calyceal stones. However, small stone size (≤2 cm, a shorter and wider infundibulum and a larger lower-pole infundibulopelvic angle seem to promote a more rapid and more complete stone clearance.

  5. Abdominal colic due to ureteric diverticulum with stone formation

    International Nuclear Information System (INIS)

    Roodhooft, A.M.; Boven, K.; Acker, K.J. van; Gentens, P.

    1987-01-01

    In a 15-year-old boy right lower abdominal colicky pain was caused by intermittent obstruction of the ureter by stones which had accumulated in a ureteric diverticulum. As was shown by repeated X-rays, each of these stones had moved to the ureter and back to the diverticulum. Ureteric diverticulum mostly remains asymptomatic in children: stone formation and obstruction of the ureter by the stones is one of the instances which may cause symptoms. (orig.)

  6. Effect of Microwave Disinfection on Compressive and Tensile Strengths of Dental Stones

    Directory of Open Access Journals (Sweden)

    Mahmood Robati Anaraki

    2013-03-01

    Full Text Available Background and aims. Although microwave irradiation has been used for disinfection of dental stone casts, there are concerns regarding mechanical damage to casts during the process. The aim of this study was to evaluate the effect of microwave irradiation on the compressive strength (CS and diametral tensile strength (DTS of stone casts. Materials and methods. In this in vitro study, 80 cylindrical type III and IV stone models (20 × 40 mm were prepared and divided into 8 groups of 10. The DTS and CS of the specimens were measured by a mechanical testing machine at a crosshead speed of 0.5 cm/min after 7 times of frequent wetting, irradiating at an energy level of 600 W for 3 minutes and cooling. Data were analyzed by Student’s t-test. Results. Microwave irradiation significantly increased DTS of type III and IV to 5.23 ± 0.64 and 8.17 ± 0.94, respectively (P < 0.01. Conclusion. According to the results, microwave disinfection increases DTS of type III and IV stone casts without any effects on their CS.

  7. Analysis of urinary stone constituents using powder X-ray diffraction ...

    Indian Academy of Sciences (India)

    WINTEC

    drug and bacteria induced factors are all external factors causing urinary stones. ... gion of hot climate, low rain fall, and increased salin- ity of ground water, is a ... Gender the patient stones the stones habit and age. Stone removal procedure. KSHP. 1. KSHP1 Vegetarian. Male, 50. Natural excretion in the urine. KSHIM. 1.

  8. Renal geology (quantitative renal stone analysis) by 'Fourier transform infrared spectroscopy'.

    Science.gov (United States)

    Singh, Iqbal

    2008-01-01

    To prospectively determine the precise stone composition (quantitative analysis) by using infrared spectroscopy in patients with urinary stone disease presenting to our clinic. To determine an ideal method for stone analysis suitable for use in a clinical setting. After routine and a detailed metabolic workup of all patients of urolithiasis, stone samples of 50 patients of urolithiasis satisfying the entry criteria were subjected to the Fourier transform infrared spectroscopic analysis after adequate sample homogenization at a single testing center. Calcium oxalate monohydrate and dihydrate stone mixture was most commonly encountered in 35 (71%) followed by calcium phosphate, carbonate apatite, magnesium ammonium hexahydrate and xanthine stones. Fourier transform infrared spectroscopy allows an accurate, reliable quantitative method of stone analysis. It also helps in maintaining a computerized large reference library. Knowledge of precise stone composition may allow the institution of appropriate prophylactic therapy despite the absence of any detectable metabolic abnormalities. This may prevent and or delay stone recurrence.

  9. [Factors affecting residual stones after percutaneous nephrolithotomy in patients with renal calculus].

    Science.gov (United States)

    Qiao, Mingzhou; Zhang, Haifang; Zhou, Chenlong

    2015-11-24

    To explore the factors affecting the residual stones after percutaneous nephrolithotomy (PCNL) in patients with renal calculus. A retrospective analysis was performed for 1 200 patients who were affected by renal calculus and treated with PCNL between Jan 2008 and May 2014 in People's Hospital of Anyang City. Among those patients, 16 were diagnosed as bilateral renal stone and had two successive operations. The size, location and number of stones, previous history of surgery, the degree of hydronephrosis, urinary infection were included in the univariate analysis. Significant factors in univariate analysis were included in the multivariate analysis to determine factors affecting stone residual. A total of 385 cases developed stone residual after surgery. The overall residual rate was 31.7%. In univariate analysis, renal pelvis combined with caliceal calculus (P=0.006), stone size larger than 4 cm (P=0.005), stone number more than 4 (P=0.002), the amount of bleeding more than 200 ml (P=0.025), operation time longer than 120 minutes (P=0.028) were associated with an increased rate of stone residual. When subjected to the Cox multivariate analysis, the independent risk factors for residual stones were renal pelvis combined with caliceal calculus (P=0.049), stone size larger than 4 cm (P=0.038) and stone number more than 4 (P=0.018). Factors affecting the incidence of residual stones after PCNL are the size, location and number of stones. Larger size stone and the presence of renal pelvis combined with caliceal calculus are significantly associated with residual stones. Nevertheless, stone number less than 4 indicates an increased stone clearance rate.

  10. Various Stone-Wales defects in phagraphene

    Science.gov (United States)

    Openov, L. A.; Podlivaev, A. I.

    2016-08-01

    Various Stone-Wales defects in phagraphene, which is a graphene allotrope, predicted recently are studied in terms of the nonorthogonal tight-binding model. The energies of the defect formation and the heights of energy barriers preventing the formation and annealing of the defects are found. Corresponding frequency factors in the Arrhenius formula are calculated. The evolution of the defect structure is studied in the real-time mode using the molecular dynamics method.

  11. Effects of microgravity on renal stone risk assessment

    Science.gov (United States)

    Pietrzyk, R. A.; Pak, C. Y. C.; Cintron, N. M.; Whitson, P. A.

    1992-01-01

    Physiologic changes induced during human exposure to the microgravity environment of space may contribute to an increased potential for renal stone formation. Renal stone risk factors obtained 10 days before flight and immediately after return to earth indicated that calcium oxalate and uric acid stone-forming potential was increased after space flights of 4-10 days. These data describe the need for examining renal stone risk during in-flight phases of space missions. Because of limited availability of space and refrigerated storage on spacecraft, effective methods must be developed for collecting urine samples in-flight and for preserving (or storing) them at temperatures and under conditions commensurate with mission constraints.

  12. Laparoscopic transperitoneal ureterolithotomy for large ureteric stones

    Directory of Open Access Journals (Sweden)

    Ahmed Al-Sayyad

    2012-01-01

    Conclusion: Laparoscopic transperitoneal ureterolithotomy is a safe and effective approach for selected patients with large proximal ureteric stones with reduced postoperative pain and short hospital stay, and should be considered as a treatment option for such stones.

  13. [Ultraminipercutaneous nephrolithotripsy in treating kidney stones].

    Science.gov (United States)

    Martov, A G; Dutov, S V; Andronov, A S

    2016-04-01

    Percutaneous nephrolithotripsy (PNL) is the recommended method of surgical treatment of kidney stones of size greater than 2 cm. Trends in the development of modern urology have been steadily toward less traumatic method to treat nephrolithiasis - minimally invasive PNL. The present work aimed to explore of the possibilities of one of the modern variants of minimally invasive PNL - ultra-mini-PNL in treating nephrolithiasis. The study included 60 patients (mean age 45.6+/-7.2 years) with isolated kidney calculus, up to 2.0 cm or several stones with a total size of up to 2.5 cm. All patients were found to have 77 kidney stones, six of which had a size of 10 mm, 51 had a size of 11-15 mm and 20 had a size of 16-20 mm. 45% of patients had isolated renal pelvic stones and 28.3% had stones in the renal pelvis and lower calyx. All patients underwent ultra-mini-PNL using nephroscope size 7.5 Ch and tube size 12 Fr. The average duration of surgery from the moment of the puncture of the pyelocaliceal system to installing the nephrostomy tube was 65.4 minutes. Complete clearance of stones after single-stage ultra-mini-PNL was observed in 80% of cases. Nephrostomy tube was removed on days 2-3. The average postoperative hospital stay was 5.1 days. The most common complication was postoperative exacerbation of pyelonephritis (13.3% of patients), successfully treated with conservative measures. There were no cases of postoperative bleeding, accompanied by anemia and needed a blood transfusion. Considering high effectiveness and low rate of complications of ultra-mini-PNL, it can be successfully used in treating nephrolithiasis among a wide group of patients.

  14. Occasional, obligatory, and habitual stone tool use in hominin evolution.

    Science.gov (United States)

    Shea, John J

    2017-09-01

    Archeologists have long assumed that earlier hominins were obligatory stone tool users. This assumption is deeply embedded in traditional ways of describing the lithic record. This paper argues that lithic evidence dating before 1.7 Ma reflects occasional stone tool use, much like that practiced by nonhuman primates except that it involved flaked-stone cutting tools. Evidence younger than 0.3 Ma is more congruent with obligatory stone tool use, like that among recent humans. The onset of habitual stone tool use at about 1.7 Ma appears correlated with increased hominin logistical mobility (carrying things). The onset of obligatory stone tool use after 0.3 Ma may be linked to the evolution of spoken language. Viewing the lithic evidence dating between 0.3-1.7 Ma as habitual stone tool use explains previously inexplicable aspects of the Early-Middle Pleistocene lithic record. © 2017 Wiley Periodicals, Inc.

  15. Kidney stone nano-structure - Is there an opportunity for nanomedicine development?

    Science.gov (United States)

    Vordos, N; Giannakopoulos, S; Gkika, D A; Nolan, J W; Kalaitzis, Ch; Bandekas, D V; Kontogoulidou, C; Mitropoulos, A Ch; Touloupidis, S

    2017-06-01

    Kidney stone analysis techniques are well-established in the field of materials characterization and provide information for the chemical composition and structure of a sample. Nanomedicine, on the other hand, is a field with an increasing rate of scientific research, a big budget and increasingly developing market. The key scientific question is if there is a possibility for the development of a nanomedicine to treat kidney stones. The main calculi characterization techniques such as X-ray Diffraction and Fourier Transform Infrared Spectroscopy can provide information about the composition of a kidney stone but not for its nanostructure. On the other hand, Small Angle X-ray Scattering and Nitrogen Porosimetry can show the nanostructural parameters of the calculi. The combination of the previously described parameters can be used for the development of nano-drugs for the treatment of urolithiasis, while no such nano-drugs exist yet. In this study, we focus on the most well-known techniques for kidney stone analysis, the urolithiasis management and the search for possible nanomedicine for the treatment of kidney stone disease. We combine the results from five different analysis techniques in order to represent a three dimensional model and we propose a hypothetical nano-drug with gold nanoparticles. This article is part of a Special Issue entitled "Recent Advances in Bionanomaterials" Guest Editor: Dr. Marie-Louise Saboungi and Dr. Samuel D. Bader. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Spectroscopy stepping stones

    International Nuclear Information System (INIS)

    Hammer, M.R.; Sturman, B.T.

    2003-01-01

    Determining the elemental composition of samples has long been a basic task of analytical science. Some very powerful and convenient approaches are based on the wavelength-specific absorption or emission of light by gas-phase atoms. Techniques briefly described as examples of analytical atomic spectrometry include atomic emission and absorption spectroscopy, inductively coupled plasma emission and mass spectroscopy and laser induced breakdown spectrometry

  17. The Stones and the Stars Building Scotland's Newest Megalith

    CERN Document Server

    Lunan, Duncan

    2013-01-01

    There are at least 48 identified prehistoric stone circles in Scotland.  In truth, very little is known about the people who erected them, and ultimately about what the stone circles were for.  Most stone circles are astronomically aligned, which has led to the modern debate over the significance of the alignments.  The megaliths certainly represented an enormous cooperative effort, would at the very least have demonstrated power and wealth, and being set away from any dwellings probably served a ceremonial, or perhaps religious, purpose. Observations at the site of the stone circles, of solar, lunar, and stellar events, have already cast light on some of the questions about the construction and use of ancient megalithic observatories. In his capacity as manager of the Glasgow Parks Department Astronomy Project, author Duncan Lunan designed and built in the late 1970s Sighthill, the first astronomically aligned stone circle in Britain in over 3,000 years.  The Stones and the Stars examines the case for as...

  18. User-centred sustainable business model design : The case of energy efficiency services in the Netherlands

    NARCIS (Netherlands)

    Tolkamp, J.; Huijben, J.C.C.M.; Mourik, R.M.; Verbong, G.P.J.; Bouwknegt, R.

    2018-01-01

    The capability to both anticipate user needs and incorporate them into a firm's value proposition is considered as an important stepping stone towards more effective and sustainable business models. However, many firms struggle to involve the user in their business model design process. Therefore we

  19. Modeling the stepping mechanism in negative lightning leaders

    Science.gov (United States)

    Iudin, Dmitry; Syssoev, Artem; Davydenko, Stanislav; Rakov, Vladimir

    2017-04-01

    It is well-known that the negative leaders develop in a step manner using a mechanism of the so-called space leaders in contrary to positive ones, which propagate continuously. Despite this fact has been known for about a hundred years till now no one had developed any plausible model explaining this asymmetry. In this study we suggest a model of the stepped development of the negative lightning leader which for the first time allows carrying out the numerical simulation of its evolution. The model is based on the probability approach and description of temporal evolution of the discharge channels. One of the key features of our model is accounting for the presence of so called space streamers/leaders which play a fundamental role in the formation of negative leader's steps. Their appearance becomes possible due to the accounting of potential influence of the space charge injected into the discharge gap by the streamer corona. The model takes into account an asymmetry of properties of negative and positive streamers which is based on well-known from numerous laboratory measurements fact that positive streamers need about twice weaker electric field to appear and propagate as compared to negative ones. An extinction of the conducting channel as a possible way of its evolution is also taken into account. This allows us to describe the leader channel's sheath formation. To verify the morphology and characteristics of the model discharge, we use the results of the high-speed video observations of natural negative stepped leaders. We can conclude that the key properties of the model and natural negative leaders are very similar.

  20. Wait-and-see policy versus cholecystectomy after endoscopic sphincterotomy for bile-duct stones in high-risk patients with co-existing gallbladder stones: a prospective randomised trial.

    Science.gov (United States)

    Zargar, Showkat A; Mushtaq, Mosin; Beg, Mashkoor A; Javaid, Gul; Khan, Bashir A; Hassan, Rayhana; Kasana, Reyaz A; Tabassum, Sameena

    2014-03-01

    Endoscopic sphincterotomy (ES) is one of the most important advances in the treatment of common bile duct (CBD) stones. However, the use of ES to remove CBD stones in high-risk patients without cholecystectomy is still debatable. The aim of this study was to compare the efficacy of a wait-and-see policy versus cholecystectomy after ES for CBD stones in high-risk patients with co-existing cholelithiasis. A total of 162 patients after undergoing ES with the clearance of CBD stones were randomised after informed consent to cholecystectomy or conservative management of their gallbladder stones. The results indicated that cholecystectomy after ES for CBD stones significantly reduced the biliary complications in high-risk patients. Every patient who has both CBD stones and gallstones with significant co-morbid illnesses, after clearance of CBD stones by ES, should undergo early cholecystectomy. Copyright © 2014 Arab Journal of Gastroenterology. Published by Elsevier Ltd. All rights reserved.

  1. Sculpture: Stone Shapes, Art: 6683.08.

    Science.gov (United States)

    Dubocq, Edward R.

    This elective course for grades 7-12 was created with a three fold purpose: 1) to create in the student an awareness of the effect of sculptural forms on his environment; 2) to introduce the student to an appreciation of stone sculpture; and 3) to further enhance the artistic abilities of the student through sculpting in stone. Course content…

  2. Stone coalgebras

    NARCIS (Netherlands)

    C.A. Kupke (Clemens); A. Kurz (Alexander); Y. Venema

    2003-01-01

    textabstractIn this paper we argue that the category of Stone spaces forms an interesting base category for coalgebras, in particular, if one considers the Vietoris functor as an analogue to the power set functor on the category of sets. We prove that the so-called descriptive general frames, which

  3. Stones used in Milan architecture

    Directory of Open Access Journals (Sweden)

    Folli, Luisa

    2008-06-01

    Full Text Available The city of Milan lies in a plain with clayey soil well suited to brick-making, but no stone deposits. An ample supply of stone is available, however, in the surrounding hills and mountains, which are connected to the city via both natural and artificial waterways. The types of stone used since Roman times include: granite, marble and gneiss from Ossola Valley; dolomite from Lake Maggiore; detrital limestone from Ceresio Valley; sandstone from the Brianza Hills; black limestone and marble from Lake Como; and conglomerate and sandstone from the Adda River basin. Traditionally, the chief uses have been dimension stone (all stones, column shafts (granite, slabs (marble, moulding (dolomite, limestone and ornamental (marble, dolomite, limestone.La ciudad de Milán se encuentra en una llanura de suelo arcilloso adecuado para la fabricación de ladrillos pero en la cual no hay yacimientos de rocas. No obstante, en las colinas y montañas circundantes, que están comunicadas con la ciudad mediante vías navegables naturales y artificiales, sí existe una abundante cantidad de piedra. Entre los tipos de piedra utilizados desde la época de los romanos se encuentran granitos, mármoles y gneises del valle de Ossola, dolomías del lago Mayor, calizas detríticas del valle de Ceresio (Lugano, areniscas de las colinas de la Brianza, calizas negras y mármoles del lago Como y conglomerados y areniscas de la cuenca del río Adda. Tradicionalmente, los principales usos han sido la piedra de fábrica (todas ellas, fustes de columnas (granito, losas (mármol, molduras (dolomía, caliza y ornamental (mármol, dolomía, caliza.

  4. Radon in houses utilizing stone magazines for heat accumulation

    International Nuclear Information System (INIS)

    Stranden, E.

    1981-01-01

    Measurements of 222 Rn and its daughters in three solar energy houses utilizing stone magazines for heat accumulation are reported. Theoretical calculations of the radon contribution from the stone magazines seem to be in good agreement with the measured values. The survey indicated that this method for heat accumulation could give a significant increase in the indoor radon concentration if the radium concentration of the stone material is high. The theoretical considerations suggest that a radium concentration of 1 pCi/g of the stone material could give an increment of the radon concentration in the indoor air of about 1 pCi/l. during the heating season in a house with air volume of 250 m 3 and a 10 5 -kg stone magazine. (author)

  5. New Experiments and a Model-Driven Approach for Interpreting Middle Stone Age Lithic Point Function Using the Edge Damage Distribution Method.

    Science.gov (United States)

    Schoville, Benjamin J; Brown, Kyle S; Harris, Jacob A; Wilkins, Jayne

    2016-01-01

    The Middle Stone Age (MSA) is associated with early evidence for symbolic material culture and complex technological innovations. However, one of the most visible aspects of MSA technologies are unretouched triangular stone points that appear in the archaeological record as early as 500,000 years ago in Africa and persist throughout the MSA. How these tools were being used and discarded across a changing Pleistocene landscape can provide insight into how MSA populations prioritized technological and foraging decisions. Creating inferential links between experimental and archaeological tool use helps to establish prehistoric tool function, but is complicated by the overlaying of post-depositional damage onto behaviorally worn tools. Taphonomic damage patterning can provide insight into site formation history, but may preclude behavioral interpretations of tool function. Here, multiple experimental processes that form edge damage on unretouched lithic points from taphonomic and behavioral processes are presented. These provide experimental distributions of wear on tool edges from known processes that are then quantitatively compared to the archaeological patterning of stone point edge damage from three MSA lithic assemblages-Kathu Pan 1, Pinnacle Point Cave 13B, and Die Kelders Cave 1. By using a model-fitting approach, the results presented here provide evidence for variable MSA behavioral strategies of stone point utilization on the landscape consistent with armature tips at KP1, and cutting tools at PP13B and DK1, as well as damage contributions from post-depositional sources across assemblages. This study provides a method with which landscape-scale questions of early modern human tool-use and site-use can be addressed.

  6. Soap-stone in architecture of North European cities. A nomination as a candidate for a Global Heritage Stones Resource

    Science.gov (United States)

    Bulakh, Andrey

    2016-04-01

    Soap stone represents soft Proterozoic rock type from the deposit Nunnalahti situated on the western shore of the big Lake Pielinen in Eastern Finland. It consists of talc (40 - 50 %), magnesite MgCO3 (40 - 50 %), chlorite (5 - 8 %), dolomite, calcite, etc. The colour of the stone is very spectacular and varies from yellow and brownish-yellow to grey, greenish grey. The soft stone is a highly workable material for a sculptor's chisel. It was one of the most popular ornamental rocks used architecture of the Modern style in St Petersburg, Helsinki, Turku, Tampere and other North European cities lately in the XIX-th centuries. Examples are given and discussed. References: Bulakh, A.G., Abakumova, N.B., and Romanovsky, J.V. St Petersburg: a History in Stone. 2010. Print House of St Petersburg State University. 173 p. (In English).

  7. Strides in Preservation of Malawi's Natural Stone

    Science.gov (United States)

    Kamanga, Tamara; Chisenga, Chikondi; Katonda, Vincent

    2017-04-01

    The geology of Malawi is broadly grouped into four main lithological units that is the Basement Complex, the Karoo Super group, Tertiary to Quaternary sedimentary deposits and the Chilwa Alkaline province. The basement complex rocks cover much of the country and range in age from late Precambrian to early Paleozoic. They have been affected by three major phases of deformation and metamorphism that is the Irumide, Ubendian and The Pan-African. These rocks comprise gneisses, granulites and schists with associated mafic, ultramafic, syenites and granite rocks. The Karoo System sedimentary rocks range in age from Permian to lower Jurassic and are mainly restricted to two areas in the extreme North and extreme Alkaline Province - late Jurassic to Cretaceous in age, preceded by upper Karoo Dolerite dyke swarms and basaltic lavas, have been intruded into the Basement Complex gneisses of southern Malawi. Malawi is endowed with different types of natural stone deposits most of which remain unexploited and explored. Over twenty quarry operators supply quarry stone for road and building construction in Malawi. Hundreds of artisanal workers continue to supply aggregate stones within and on the outskirts of urban areas. Ornamental stones and granitic dimension stones are also quarried, but in insignificant volumes. In Northern Malawi, there are several granite deposits including the Nyika, which is the largest single outcrop occupying approximately 260.5 km2 , Mtwalo Amazonite an opaque to translucent bluish -green variety of microcline feldspar that occurs in alkali granites and pegmatite, the Ilomba granite (sodalite) occurring in small areas within biotite; apatite, plagioclase and calcite. In the Center, there are the Dzalanyama granites, and the Sani granites. In the South, there are the Mangochi granites. Dolerite and gabbroic rocks spread across the country, treading as black granites. Malawi is also endowed with many deposits of marble. A variety of other igneous

  8. Nanobacteria: An Infectious Cause for Salivary Stone Formation and Recurrence

    Directory of Open Access Journals (Sweden)

    Amr A El Badry

    2010-01-01

    Full Text Available Nanobacteria (NB contribute to pathological calcification in the human and animal body. It has been isolated from salivary stones and suggested that it may act as a nucleus for the initiation of these stones. In the present study, we examined its role in the recurrent salivary gland stones using immunodetection with NB-specific monoclonal antibodies and scanning electron microscopy (SEM hoping to provide a method for preventing the recurrence of these stones in the patient that has suffered from salivary stones. Our study comprised 30 patients with recurrent salivary gland stones (group I and 30 patients with salivary gland stones for the first time (group II, in addition to 30 normal controls (group III. We could detect 100–500 nm nanoparticles in 24/30 (80% cases in group I with significant difference <0.05 and <0.01 when compared with group II and group III in which they were detected in 19/30 (63.3% and 6/30 (20% respectively. Also there was a significant difference <0.05 between group II and group III. We proposed that salivary stone formation is a nanobacterial disease initiated by bacterial infection. This bacteria may play an important role in the recurrence of salivary stone. So the use of calcium chelator, ethylene diamine tetra acetic acid (EDTA, before or in combination with the suitable antibiotic that is given in an amount effective to inhibit or prevent the growth and development of nanobacteria may eradicate these stones and prevent their recurrence.

  9. Data Package for Secondary Waste Form Down-Selection-Cast Stone

    International Nuclear Information System (INIS)

    Serne, R. Jeffrey; Westsik, Joseph H.

    2011-01-01

    Available literature on Cast Stone and Saltstone was reviewed with an emphasis on determining how Cast Stone and related grout waste forms performed in relationship to various criteria that will be used to decide whether a specific type of waste form meets acceptance criteria for disposal in the Integrated Disposal Facility (IDF) at Hanford. After the critical review of the Cast Stone/Saltstone literature, we conclude that Cast Stone is a good candidate waste form for further consideration. Cast stone meets the target IDF acceptance criteria for compressive strength, no free liquids, TCLP leachate are below the UTS permissible concentrations and leach rates for Na and Tc-99 are suiteably low. The cost of starting ingredients and equipment necessary to generate Cast Stone waste forms with secondary waste streams are low and the Cast Stone dry blend formulation can be tailored to accommodate variations in liquid waste stream compositions. The database for Cast Stone short-term performance is quite extensive compared to the other three candidate waste solidification processes. The solidification of liquid wastes in Cast Stone is a mature process in comparison to the other three candidates. Successful production of Cast Stone or Saltstone has been demonstrated from lab-scale monoliths with volumes of cm3 through m3 sized blocks to 210-liter sized drums all the way to the large pours into vaults at Savannah River. To date over 9 million gallons of low activity liquid waste has been solidified and disposed in concrete vaults at Savannah River.

  10. Data Package for Secondary Waste Form Down-Selection—Cast Stone

    Energy Technology Data Exchange (ETDEWEB)

    Serne, R. Jeffrey; Westsik, Joseph H.

    2011-09-05

    Available literature on Cast Stone and Saltstone was reviewed with an emphasis on determining how Cast Stone and related grout waste forms performed in relationship to various criteria that will be used to decide whether a specific type of waste form meets acceptance criteria for disposal in the Integrated Disposal Facility (IDF) at Hanford. After the critical review of the Cast Stone/Saltstone literature, we conclude that Cast Stone is a good candidate waste form for further consideration. Cast stone meets the target IDF acceptance criteria for compressive strength, no free liquids, TCLP leachate are below the UTS permissible concentrations and leach rates for Na and Tc-99 are suiteably low. The cost of starting ingredients and equipment necessary to generate Cast Stone waste forms with secondary waste streams are low and the Cast Stone dry blend formulation can be tailored to accommodate variations in liquid waste stream compositions. The database for Cast Stone short-term performance is quite extensive compared to the other three candidate waste solidification processes. The solidification of liquid wastes in Cast Stone is a mature process in comparison to the other three candidates. Successful production of Cast Stone or Saltstone has been demonstrated from lab-scale monoliths with volumes of cm3 through m3 sized blocks to 210-liter sized drums all the way to the large pours into vaults at Savannah River. To date over 9 million gallons of low activity liquid waste has been solidified and disposed in concrete vaults at Savannah River.

  11. Multiple plastic biliary stent placement in the management of large and multiple choledochal stones: single center experience and review of the literature.

    Science.gov (United States)

    Bektaş, Hasan; Gürbulak, Bünyamin; Şahin, Zeynep Deniz; Düzköylü, Yiğit; Çolak, Şükrü; Gürbulak, Esin Kabul; Güneş, Mehmet Emin; Çakar, Ekrem

    2017-09-01

    Endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy is the first step treatment modality of choledocholithiasis. In spite of an extended sphincterotomy, 10-15% of complex choledochal stones (larger than 15 mm and/or more than 3 stones) cannot be removed and recurrent ERCP procedures may be needed. To evaluate the role and efficiency of multiple biliary stent application in the treatment of large and multiple choledochal stones. Patients with complex choledochal stones and patients with inadequate choledochal clearance during ERCP were included in the study. The study group was divided into 2 groups as the placement of single (n = 27 patients) or multiple stents (n = 58 patients). After a mean time interval of 21 days (10-28), the ERCP procedure was tried for the second time and a stent was placed in case of recurrence. Successful biliary drainage was provided in both groups. The decrease in the longitudinal or transverse size of the stones after stent placement was found to be statistically significant in both groups (p = 0.001). Cholestatic enzymes (alkaline phosphatase (ALP), γ-glutamyltransferase (GGT)) and bilirubin levels decreased significantly in both groups following stenting (p = 0.001). Additionally, multiple stents functioned as a bridge starting from the first ERCP to full clearance in patients with large and multiple stones which could not be removed at once and saved them from the possible morbidities of an invasive operation. Endoscopic multiple biliary stent placement should be preferred in the treatment of patients with complex choledochal stones and high rates of co-morbidity, as a safe alternative to surgery.

  12. Stone Formation in the Infected Pediatric Enterocystoplasty

    NARCIS (Netherlands)

    R.B. Mathoera (Rejiv)

    2003-01-01

    markdownabstract__Abstract__ Proteus mirabilis is one of the most frequent bacterial agents that can induce infection stone formation by urease production. In recent years the influence of Proteus mirabilis on stone formation in enterocystoplasties has been primarily related to the presence of

  13. Novelda Stone: widely used within the Spanish architectural heritage

    OpenAIRE

    Fort, R.; Bernabeu, A.; García del Cura, M. A.; López de Azcona, M. C.; Ordóñez, S.; Mingarro, F.

    2002-01-01

    Novelda Stone is a calcareous rock, of the biocalcarenite type. It is extracted from the «Vinalopó Medio» area (Alicante, eastern Spain). Novelda stone is known as construction material from the 13th century. From final of the 19th century until the present time, it has been used in Madrid, Valencia and Alicante. In the past, the main quarries from which this type of rock was extracted were located in the municipal districts of Monóvar (Almorquí Stone), Sax (Portazgo Stone) and Elda (Bateig S...

  14. Melting behaviour of raw materials and recycled stone wool waste

    DEFF Research Database (Denmark)

    Schultz-Falk, Vickie; Agersted, Karsten; Jensen, Peter Arendt

    2018-01-01

    Stone wool is a widely used material for building insulation, to provide thermal comfort along with fire stability and acoustic comfort for all types of buildings. Stone wool waste generated either during production or during renovation or demolition of buildings can be recycled back into the sto...... wool melt production. This study investigates and compares the thermal response and melting behaviour of a conventional stone wool charge and stone wool waste. The study combines differential scanning calorimetry (DSC), hot stage microscopy (HSM) and X-ray diffraction (XRD). DSC reveals...... that the conventional charge and stone wool waste have fundamentally different thermal responses, where the charge experiences gas release, phase transition and melting of the individual raw materials. The stone wool waste experiences glass transition, crystallization and finally melting. Both DSC and HSM measurements...

  15. Risk Factors for Recurrence of Symptomatic Common Bile Duct Stones after Cholecystectomy

    Directory of Open Access Journals (Sweden)

    Ju Hyun Oak

    2012-01-01

    Full Text Available Purpose. The recurrence of CBD stone is still observed in a considerable number of patients. The study was to evaluate the risk factors for recurrence of symptomatic CBD stone in patients who underwent cholecystectomy after the removal of CBD stone. Methods. The medical records of patients who underwent removal of CBD stone with subsequent cholecystectomy were reviewed. The risk factors for the recurrence of symptomatic CBD stone were compared between the recurrence and the nonrecurrence group. Results. The mean follow-up period was 40.6 months. The recurrence of symptomatic CBD stones was defined as the detection of bile duct stones no sooner than 6 months after complete clearance of CBD stones, based on symptoms or signs of biliary complication. 144 patients (68 males, 47.2% were finally enrolled and their mean age was 59.8 (range: 26~86 years. The recurrence of CBD stone occurred in 15 patients (10.4%. The mean period until first recurrence was 25.9 months. The presence of type 1 or 2 periampullary diverticulum and multiple CBD stones were the independent risk factors. Conclusion. For the patients with type 1 or 2 periampullary diverticulum or multiple CBD stones, careful followup is needed for the risk in recurrence of symptomatic CBD stone.

  16. Study of renal stones complications in 200 patients in Tabriz, Iran

    Directory of Open Access Journals (Sweden)

    Hamid Noshad

    2014-11-01

    Full Text Available Introduction: Urinary stones are the third most common disease of the urinary. Renal stones may lead to some preventable complications. This study was designed to investigation and prediction of these complications. Methods: In this cross-sectional study, 200 patients with kidney stones were enrolled. Kidney stone was confirmed and proven in all patients referred to Sina and Shaikh Al-Rais clinics. Their demographic characteristics like gender, age, stone number, stone type, renal failure and bio-chemistry data were evaluated. Results: Of 200 patients, 130 cases (65.0% were male and 70 cases (35.0% were female. The mean age of patients was 41.30 ± 16.06 years. Type of stone was (when evaluation was possible was mixed (11.5%. However, the type of stone was not analyzed in 112 cases (56.0%. Among complications, recurrent infection was seen (16.0%, and staghorn stones were seen in 2.5% of patients. Dialysis was positive in 3 patients (1.5%. History of surgery was positive in 3 patients (1.5%. Extracorporeal shock wave lithotripsy (ESWL history was positive in 8%. In evaluated patients, the mean level of calcium was 8.83 ± 0.27, phosphorus was 4.60 ± 0.33, parathyroid hormone (PTH was 35.20 ± 14.22, uric acid was 4.98 ± 1.57, creatinine was 1.38 ± 1.02 and blood urea nitrogen level was 16.69 ± 11.54 mg/dl. Staghorn stones are significantly associated with progression to renal failure and subsequent complications such as hemodialysis (P = 0.001, surgery (P = 0.001. Recurrent infection was more frequent in calcium-containing stones (P = 0.001 and ESWL undergoing patients (P = 0.030. Stone numbers were more than 3 in hemodialyzed (HD patients (P = 0.001. Uric acid stones were more seen in HD patients (P = 0.170. Conclusion: According to results hemodialysis and recurrent infections are seen in patients with renal stones, and they may be detected in earlier with close periodic follow-up.

  17. The Civil Palaces in Gravina street, Alicante: building stones and salt weathering

    OpenAIRE

    Louis, M.; García del Cura, M. A.; Spairani, Y.; de Blas, D.

    2001-01-01

    This paper presents a study into the architecture and construction of the 18th Century Civil Palaces located in Gravina street (Provincial Museum of Fine Arts of Alicante), the building stones used and the mineral related decay processes that these materials have suffered. The original building stones and other stones used in subsequent restorations in these Civil Palaces are bioclastic limestones and/or calcarenites (San Julian Stone and Bateig Stone). Campello stone and other limestones ...

  18. Predicting stone composition before treatment – can it really drive clinical decisions?

    Science.gov (United States)

    Bres–Niewada, Ewa; Radziszewski, Piotr

    2014-01-01

    Introduction Determination of stone composition is considered to be crucial for the choice of an optimal treatment algorithm. It is especially important for uric acid stones, which can be dissolved by oral chemolysis and for renal stones smaller than 2 cm, which can be treated with extracorporeal shockwave lithotripsy (ESWL). Material and methods This short review identifies the latest papers on radiological assessment of stone composition and presents a comprehensive evaluation of current scientific findings. Results Stone chemical composition is difficult to predict using standard CT imaging, however, attenuation index measured in Hounsfield units (HU) is related to ESWL outcome. Stone density >1000 HU can be considered predictive for ESWL failure. It seems that stone composition is meaningless in determining the outcome of ureterolithotripsy and percutaneous surgery. Alternative imaging techniques such as Dual–Energy CT or analysis of shape, density and homogeneity of stones on plain X–rays are used as promising methods of predicting stone composition and ESWL outcome. Conclusions New imaging techniques facilitate the identification of uric acid stones and ESWL–resistant stones. Therefore, they may help in selecting the best therapeutic option. PMID:25667761

  19. Building HIA approaches into strategies for green space use: an example from Plymouth's (UK) Stepping Stones to Nature project.

    Science.gov (United States)

    Richardson, J; Goss, Z; Pratt, A; Sharman, J; Tighe, M

    2013-12-01

    The health and well-being benefits of access to green space are well documented. Research suggests positive findings regardless of social group, however barriers exist that limit access to green space, including proximity, geography and differing social conditions. Current public health policy aims to broaden the range of environmental public health interventions through effective partnership working, providing opportunities to work across agencies to promote the use of green space. Health Impact Assessment (HIA) is a combination of methods and procedures to assess the potential health and well-being impacts of policies, developments and projects. It provides a means by which negative impacts can be mitigated and positive impacts can be enhanced, and has potential application for assessing green space use. This paper describes the application of a HIA approach to a multi-agency project (Stepping Stones to Nature--SS2N) in the UK designed to improve local green spaces and facilitate green space use in areas classified as having high levels of deprivation. The findings suggest that the SS2N project had the potential to provide significant positive benefits in the areas of physical activity, mental and social well-being. Specific findings for one locality identified a range of actions that could be taken to enhance benefits, and mitigate negative factors such as anti-social behaviour. The HIA approach proved to be a valuable process through which impacts of a community development/public health project could be enhanced and negative impacts prevented at an early stage; it illustrates how a HIA approach could enhance multi-agency working to promote health and well-being in communities.

  20. Emergency extracorporeal shock wave lithotripsy (ESWL) for obstructing ureteral stones.

    Science.gov (United States)

    Tligui, M; El Khadime, M R; Tchala, K; Haab, F; Traxer, O; Gattegno, B; Thibault, P

    2003-05-01

    To evaluate emergency treatment of obstructing ureteral stones by in situ extracorporeal shock wave lithotripsy (ESWL) during acute renal colic. From January 1994 to February 2000, 200 patients (mean age: 42 years) were treated by ESWL (EDAP LT-02) for obstructing ureteral stones causing acute renal colic refractory to medical treatment or recurring within 24hours of such treatment. Stones were visualised by fluoroscopic imaging and/or ultrasound. Follow-up included radiological and/or ultrasound examinations and lasted three months. Mean stone size was 7mm (3-20mm). At three months, 164/200 (82%) patients were stone-free. This rate ranged from 79% to 83% according to the location of the stone, and from 75% to 86% according to the size of the stone. These differences in rate were not significant. Two or three ESWL sessions were required in 79 patients. ESWL was well tolerated in 90% of patients. The only complication was a case of pyelonephritis requiring the placement of a JJ stent, administration of antibiotics, and distant ureteroscopy. The 36 patients, in whom ESWL failed, underwent ureteroscopy (n=23) or lithotripsy with a Dornier machine (n=13). Non-deferred ESWL for acute renal colic secondary to obstructing ureteral stones has a satisfactory success rate and very low morbidity.

  1. Is pre-operative imaging essential prior to ureteric stone surgery?

    Science.gov (United States)

    Youssef, F R; Wilkinson, B A; Hastie, K J; Hall, J

    2012-09-01

    The aim of this study was to identify patients not requiring ureteric stone surgery based on pre-operative imaging (within 24 hours) prior to embarking on semirigid ureteroscopy (R-URS) for urolithiasis. The imaging of all consecutive patients on whom R-URS for urolithiasis was performed over a 12-month period was reviewed. All patients had undergone a plain x-ray of the kidney, ureters and bladder (KUB), abdominal non-contrast computed tomography (NCCT-KUB) or both on the day of surgery. A total of 96 patients were identified for the study. Stone sizes ranged from 3 mm to 20 mm. Thirteen patients (14%) were cancelled as no stone(s) were identified on pre-operative imaging. Of the patients cancelled, 8 (62%) required NCCT-KUB to confirm spontaneous stone passage. One in seven patients were stone free on the day of surgery. This negates the need for unnecessary anaesthetic and instrumentation of the urinary tract, with the associated morbidity. Up-to-date imaging prior to embarking on elective ureteric stone surgery is highly recommended.

  2. Clinical experience for radiolucent stones; A report of 27 cases

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyung Jee; Lee, Gil Ho [Dankook University, Seoul (Korea, Republic of)

    1997-02-01

    The cause of radiolucent filling defects in the upper urinary tract are malignant tumor, radiolucent stones, blood clots, air bubbles, congenital deformities of renal parenchyme, and various specific and non-specific infection and their sequence. So the differential diagnosis between malignancy and radiolucent stones is very important, and the exact and fast diagnosis of radiolucent stones is useful in excluding the possibility of malignancy. 27 cases with radiolucent stones were evaluated retrospectively for exact diagnosis and appropriate treatment method. Intravenous urography was done in all cases, and retrograde pyelography, ultrasonography, computed tomography and/or ureterorenoscopy were performed for diagnosis, if needed. Size of stones were measured below 10mm by transverse length in 19 cases (70.4%) with a range of 3 to 30mm. The locations of stones were pelvicalyceal system in 8 cases (29.6%) and ureter in 19 cases (70.4%). Among the diagnostic methods, computed tomography was used most frequency. ESWL with retrograde pyelography was most frequent used method of treatment, also simple hydration to small stone was effective. (author).

  3. Clinical experience for radiolucent stones; A report of 27 cases

    International Nuclear Information System (INIS)

    Kim, Hyung Jee; Lee, Gil Ho

    1997-01-01

    The cause of radiolucent filling defects in the upper urinary tract are malignant tumor, radiolucent stones, blood clots, air bubbles, congenital deformities of renal parenchyme, and various specific and non-specific infection and their sequence. So the differential diagnosis between malignancy and radiolucent stones is very important, and the exact and fast diagnosis of radiolucent stones is useful in excluding the possibility of malignancy. 27 cases with radiolucent stones were evaluated retrospectively for exact diagnosis and appropriate treatment method. Intravenous urography was done in all cases, and retrograde pyelography, ultrasonography, computed tomography and/or ureterorenoscopy were performed for diagnosis, if needed. Size of stones were measured below 10mm by transverse length in 19 cases (70.4%) with a range of 3 to 30mm. The locations of stones were pelvicalyceal system in 8 cases (29.6%) and ureter in 19 cases (70.4%). Among the diagnostic methods, computed tomography was used most frequency. ESWL with retrograde pyelography was most frequent used method of treatment, also simple hydration to small stone was effective. (author)

  4. Influence of alginate impression materials and storage time on surface detail reproduction and dimensional accuracy of stone models.

    Science.gov (United States)

    Guiraldo, Ricardo D; Moreti, Ana F F; Martinelli, Julia; Berger, Sandrine B; Meneghel, Luciana L; Caixeta, Rodrigo V; Sinhoreti, Mário A C

    2015-01-01

    This study compared the surface detail reproduction and dimensional accuracy of stone models obtained from molds prepared using different alginate impression materials (Cavex ColorChange, Hydrogum 5, or Jeltrate Plus) and with different storage times (1, 3, and 5 days) to models from molds that were filled immediately with no storage time. The molds were prepared over a matrix containing 50-μm line, (ISO 1563 standard) under pressure with a perforated metal tray. The molds were removed 2 minutes after loss of sticky consistency and either filled immediately or stored in closed jars at 100% relative humidity and 37°C for 1, 3, or 5 days. The molds were filled with dental plaster (Durone IV). Surface detail reproduction and dimensional accuracy were evaluated using optical microscopy on the 50-μm wide line, which was 25 mm in length, according to ISO 1563 standard. The dimensional accuracy results (%) were subjected to analysis of variance. The 50-μm wide line (ISO 1563 standard) was completely reproduced by all alginate impression materials regardless of the storage time. There was no statistically significant difference in the mean dimensional accuracy values of stone models made from molds composed of different alginate impression materials and with different storage times (p = 0.989). In conclusion, storing the mold for five days prior to filling did not change the surface detail reproduction or dimensional accuracy of the alginates examined in this study.

  5. Screening renal stone formers for distal renal tubular acidosis

    DEFF Research Database (Denmark)

    Osther, P J; Hansen, A B; Røhl, H F

    1989-01-01

    A group of 110 consecutive renal stone formers were screened for distal renal tubular acidosis (RTA) using morning fasting urinary pH (mfUpH) levels followed by a short ammonium chloride loading test in patients with levels above 6.0. In 14 patients (12.7%) a renal acidification defect was noted...... RTA in renal stone formers. Regardless of whether the acidification defect is primary or secondary to stone formation, however, all renal stone formers with distal RTA can expect to benefit from prophylactic alkaline therapy and it is recommended that the screening procedure, which is easy to use...

  6. HIA, the next step: Defining models and roles

    International Nuclear Information System (INIS)

    Putters, Kim

    2005-01-01

    If HIA is to be an effective instrument for optimising health interests in the policy making process it has to recognise the different contests in which policy is made and the relevance of both technical rationality and political rationality. Policy making may adopt a rational perspective in which there is a systematic and orderly progression from problem formulation to solution or a network perspective in which there are multiple interdependencies, extensive negotiation and compromise, and the steps from problem to formulation are not followed sequentially or in any particular order. Policy problems may be simple with clear causal pathways and responsibilities or complex with unclear causal pathways and disputed responsibilities. Network analysis is required to show which stakeholders are involved, their support for health issues and the degree of consensus. From this analysis three models of HIA emerge. The first is the phases model which is fitted to simple problems and a rational perspective of policymaking. This model involves following structured steps. The second model is the rounds (Echternach) model that is fitted to complex problems and a network perspective of policymaking. This model is dynamic and concentrates on network solutions taking these steps in no particular order. The final model is the 'garbage can' model fitted to contexts which combine simple and complex problems. In this model HIA functions as a problem solver and signpost keeping all possible solutions and stakeholders in play and allowing solutions to emerge over time. HIA models should be the beginning rather than the conclusion of discussion the worlds of HIA and policymaking

  7. Toets van STONE versie 2.0. Samenvatting en belangrijkste resultaten

    NARCIS (Netherlands)

    Tiktak A; Beusen AHW; Boumans LJM; Groenedijk P; Haan BJ de; Portielje R; Schotten CGJ; Wolf J; Alterra; RIZA; LDL; IMP; Alterra; RIZA

    2003-01-01

    The STONE model for nitrogen and phosphorus emission to the groundwater and surface waters has been developed to evaluate the environmental consequences of policies regarding manure and agriculture. In 2000, an advisory body ('The Spiertz Commission') explicitly asked for validation of the Dutch

  8. Multi-Decadal Variability in the Bering Sea: A Synthesis of Model Results and Observations from 1948 to the Present

    Science.gov (United States)

    2013-12-01

    stated that the development and use of high-resolution Arctic climate and systems models are important stepping stones for dedicated studies of...W., J. L. Clement Kinney, D. C. Marble , and J. Jakacki, 2008: Towards eddy resolving models of the Arctic Ocean: Ocean Modeling in an Eddying

  9. Frequency of stone clearance after extracorporeal shockwave ...

    African Journals Online (AJOL)

    Objective: To determine the rate of stone clearance after extracorporeal shockwave lithotripsy (ESWL) for renal stones in adult patients with renal insufficiency. Subjects and methods: This is a cross-sectional descriptive study of 117 adult patients who underwent ESWL. The indications for ESWL were determined by the ...

  10. EPR of some irradiated renal stones

    International Nuclear Information System (INIS)

    Koeseoglu, R.; Koeseoglu, E.; Koeksal, F.; Basaran, E.; Demirci, D.

    2005-01-01

    Some renal stones were investigated by electron paramagnetic resonance of their untreated, UV-photolyzed and gamma-irradiated states. Powder X-ray diffraction technique indicated that the renal stones were made mainly from CaC 2 O 4 , MgC 2 O 4 , MgCO 3 and NH 4 MgPO 4 .6H 2 O. Before radiation treatment, the renal stones yielded a signal that could be attributed to a C 2 O 4 - radical. UV-photolysis seems to slightly increase the intensity of this signal, but does not produce any new centres. Gamma-irradiation initially gives -CH 2 C (CH 3 )-R and CO 2 - radicals, and while the intensity of the -CH 2 C (CH 3 )-R signal decreases, the intensity of the CO 2 - signal increases as time elapses

  11. Low Bone Density and Bisphosphonate Use and the Risk of Kidney Stones.

    Science.gov (United States)

    Prochaska, Megan; Taylor, Eric; Vaidya, Anand; Curhan, Gary

    2017-08-07

    Previous studies have demonstrated lower bone density in patients with kidney stones, but no longitudinal studies have evaluated kidney stone risk in individuals with low bone density. Small studies with short follow-up reported reduced 24-hour urine calcium excretion with bisphosphonate use. We examined history of low bone density and bisphosphonate use and the risk of incident kidney stone as well as the association with 24-hour calcium excretion. We conducted a prospective analysis of 96,092 women in the Nurses' Health Study II. We used Cox proportional hazards models to adjust for age, body mass index, thiazide use, fluid intake, supplemental calcium use, and dietary factors. We also conducted a cross-sectional analysis of 2294 participants using multivariable linear regression to compare 24-hour urinary calcium excretion between participants with and without a history of low bone density, and among 458 participants with low bone density, with and without bisphosphonate use. We identified 2564 incident stones during 1,179,860 person-years of follow-up. The multivariable adjusted relative risk for an incident kidney stone for participants with history of low bone density compared with participants without was 1.39 (95% confidence interval [95% CI], 1.20 to 1.62). Among participants with low bone density, the multivariable adjusted relative risk for an incident kidney stone for bisphosphonate users was 0.68 (95% CI, 0.48 to 0.98). In the cross-sectional analysis of 24-hour urine calcium excretion, the multivariable adjusted mean difference in 24-hour calcium was 10 mg/d (95% CI, 1 to 19) higher for participants with history of low bone density. However, among participants with history of low bone density, there was no association between bisphosphonate use and 24-hour calcium with multivariable adjusted mean difference in 24-hour calcium of -2 mg/d (95% CI, -25 to 20). Low bone density is an independent risk factor for incident kidney stone and is associated with

  12. "Piedra Franca": the same name for many different natural stones.

    Science.gov (United States)

    Pereira, Dolores; Navarro, Rafael; Baltuille, Jose Manuel

    2014-05-01

    The Spanish name "Piedra Franca" refers to all the stones of sedimentary origin that have uniform coloration and easeof cutting/carving in order to obtain dimensional blocks for construction. The first references to this denomination occurred during medieval times, when builders had to choose the best materials to construct magnificent cathedrals. The largest volume of such natural stones were extracted from Caen, northern France, and historic records use the English term, "freestone", ie stone easy to cut, and to work by the masons dedicated to build cathedrals ("freemasons") in contrast to the "roughstone", hard stones worked by the hard hewers or "rough masons". The original French name referred to the limestones extracted at Caen, but over time, the original meaning expanded to include other natural stones with similar coloration and ease to carve. Notably this included many sandstones that were used in adjacent countries such as Spain. In the latter, although the most popular for its importance in architectural heritage is the Villamayor sandstone from Salamanca, other historically important natural stones are also known as "Piedra Franca" including the calcarenite from Santa Pudia (Granada), the limestone from Alava, the sandstone from Jaen and the sandstone from Cádiz. All of them were used in the construction of Spanish architectonic heritage and share similar exterior characteristics. In fact, several are known as golden stones. However when conservation and restoration of architectonic heritage is involved, the correct and original material should be used. The existence of national networks (e.g. CONSTRUROCK) and international task groups (e.g. IUGS Heritage Stone Task Group) can help to properly characterize, document, and differentiate between the varieties of "Piedra Franca" and they should be consulted by builders, architects and any other stone professsionals involved in such activities. An error in choosing the natural stone can result in

  13. Smad signaling pathway in pathogenesis of kidney injury induced by calcium oxalate stone in rats

    Directory of Open Access Journals (Sweden)

    Fan Zhang

    2016-10-01

    Full Text Available Objective: To investigate the involvement of Smad signaling pathway in the pathogenesis of kidney injury induced by calcium oxalate stone in rats to provide a reference for clinical treatment. Methods: Clean SD rats were randomly divided into 3 group, namely the control group, model group and pirfenidone group. Ethylene glycol + αhydroxy vitamin D3 was used as a stone-inducing agent to replicate the renal calcium oxalate stone model. Rats in the pirfenidone group were treated with pirfenidone intragastric administration. The serum Cr, BUN and 24-hour oxalate and calcium in renal tissues were assayed. The expressions of Bax/ Bcl2 protein, Caspase3 protein, TGFβ, Smad1, Smad2 and Smad3 proteins were detected by the fluorescent quantitation PCR method. Results: Compared with the rats of the control group, the results showed that the levels of serum BUN, Cr and 24-hour oxalate in rats of the model group were increased greatly, Bax and Caspase3 mRNA also increased while the level of Bcl2 decreased significantly, and the expressions of TGFβ, Smad1, Smad2 and Smad3 proteins increased distinctly as well (P<0.01. These abnormal parameters could be normalized effectively by pirfenidone. Conclusions: Activated TGFβ/Smad signaling pathway is involved in the pathogenesis of kidney injury induced by calcium oxalate stone in rats.

  14. Dual-source dual-energy CT for the differentiation of urinary stone composition: preliminary study

    International Nuclear Information System (INIS)

    Yang Qifang; Zhang Wanshi; Meng Limin; Shi Huiping; Wang Dong; Bi Yongmin; Li Xiangsheng; Fang Hong; Guo Heqing; Yan Jingmin

    2011-01-01

    Objective: To evaluate dual-source dual-energy CT (DSCT) for the differentiation of' urinary stone composition in vitro. Methods: Ninety-seven urinary stones were obtained by endoscopic lithotripsy and scanned using dual-source dual-energy CT. The stones were divided into six groups according to infrared spectroscopy stone analysis: uric acid (UA) stones (n=10), cystine stones (n=5), struvite stones (n=6), calcium oxalate (CaOx) stones (n=22), mixed UA stones (n=7) and mixed calcium stones (n=47). Hounsfield units (HU) of each stone were recorded for the 80 kV and the 140 kV datasets by hand-drawing method. HU difference, HU ratio and dual energy index (DEI) were calculated and compared among the stone groups with one-way ANOVA. Using dual energy software to determine the composition of all stones, results were compared to infrared spectroscopy analysis. Results: There were statistical differences in HU difference [(-17±13), (229±34), (309±45), (512±97), (201±64) and (530±71) HU respectively], in HU ratio (0.96±0.03, 1.34±0.04, 1.41±0.03, 1.47±0.03, 1.30±0.07, and 1.49±0.03 respectively), and DEI (-0.006±0.004, 0.064±0.007, 0.080± 0.007, 0.108±0.011, 0.055±0.014 and 0.112±0.008 respectively) among different stone groups (F= 124.894, 407.028, 322.864 respectively, P<0.01). There were statistical differences in HU difference, HU ratio and DEI between UA stones and the other groups (P<0.01). There were statistical differences in HU difference, HU ratio and DEI between CaOx or mixed calcium stones and the other four groups (P< 0.01). There was statistical difference in HU ratio between cystine and struvite stones (P<0.01). There were statistical differences in HU difference, HU ratio and DEI between struvite and mixed UA stones (P< 0.05). Dual energy software correctly characterized 10 UA stones, 4 cystine stones, 22 CaOx stones and 6 mixed UA stones. Two struvite stones were considered to contain cystine. One cystine stone, 1 mixed UA stone, 4

  15. In vitro differentiation of renal stone composition using dual-source, dual-energy CT

    International Nuclear Information System (INIS)

    Zhou Changsheng; Zhang Longjiang; Xu Feng; Qi Li; Zhao Yan'e; Zheng Ling; Huang Wei; Liu Youhuang; Lu Guangming

    2012-01-01

    Objective: To evaluate the ability of dual-source. dual-energy CT in differentiating uric acid stones from non-uric acid stones with infrared spectroscopy as reference standard. Materials and Methods: Urinary calculus from 308 patients were scanned in first generation dual-source CT with dual-energy mode between July 2011 and June 2012. Renal Stone application was used to analyze their composition. The uric acid stones color were coded red and non-uric acid stones were blue. CT values were measured in 60 selective urinary calculus including 30 uric acid stones and 30 non-uric acid stones. The accuracy of dual energy CT to differentiate uric acid and no-uric acid stones was calculated. Results: Of 308 patients, 60 patients had uric acid stones and 248 non-uric acid stones. No difference was found for uric acid stone at 80 kV and 140 kV (375.8±69.2 HU vs. 374.1±69.4 HU; t=-0.217, P=0.830), while CT values of non-uric acid stones were higher at 80 kV than those at 140 kV (1455.1±312.4 HU vs. 1039.6±194.4 HU; t=-12.16. P<0.001). CT values of non-uric acid stones at 80 kV, 140 kV, and average weighted images (1455.1±312.4 HU, 1 039.6±194.4 HU, and 882.0±176.4 HU, respectively) were higher than those of uric acid stones (375.8±69.2 HU, 374.1±69.4 HU, and 366.3±80.1 HU, respectively; P<0.001). With infrared spectrum findings as reference standard, the accuracy of dual energy CT in differentiating uric acid stones from non-uric acid stones was 100%. Conclusions: Dual-source, dual-energy CT can accurately differentiate uric acid stones from non-uric acid stones, and plays an important role in treatment planning of renal stones. (authors)

  16. Patients' selection for treatment of caliceal diverticular stones with extracorporeal shock wave lithotripsy

    International Nuclear Information System (INIS)

    Lee, Won Hong; Lee, Hee Jeong; Son, Soon Yong; Kang, Seong Ho; Cho, Cheong Chan; Ryu, Meung Sun; Kim, Seung Kook

    2001-01-01

    Symptoms of caliceal diverticular stones are commonly associated with pain, recurrent urinary tract infection and hematuria. The aim of this study is to select the proper patient for the application of more successful extracorporeal shock wave lithotripsy(ESWL) as a treatment of caliceal diverticular stone. 16 patients with caliceal diverticular stones were treated with ESWL, and all patients had single caliceal diverticulum. The diagnosis of caliceal diverticulum with stones was made by intraveneous pyelography to all patients. On these intravenous pyelogram, we also classified diverticular type, whether the diverticular neck is connected with urinary tract patently, diverticular site and stone number and size. All patients were followed after ESWL by plain film of the kidneys, ureters and bladder and interviewed. Of all patients 44% was shown stone-free completely, also 83% was rendered symptom-free. All patients whose diverticular neck connected with urinary tract patently on the intraveneous pyelogram became stone-free. Of solitary stone 60% and multiple stones (more than 2) 17% became symptom-free. The patients with infection before ESWL 75% had residual stones, of these patients 33% had slightly flank pain, and 25% of patients with stones recurred become stone-free. We propose that more successful ESWL for patients with caliceal diverticular stones select satisfactory patients including that the diverticular neck is connected with urinary tract patently, solitary stone and no infection simultaneously

  17. Management of Asymptomatic Renal Stones in Astronauts

    Science.gov (United States)

    Reyes, David; Locke, James

    2016-01-01

    Introduction: Management guidelines were created to screen and manage asymptomatic renal stones in U.S. astronauts. The risks for renal stone formation in astronauts due to bone loss and hypercalcuria are unknown. Astronauts have a stone risk which is about the same as commercial aviation pilots, which is about half that of the general population. However, proper management of this condition is still crucial to mitigate health and mission risks in the spaceflight environment. Methods: An extensive review of the literature and current aeromedical standards for the monitoring and management of renal stones was done. The NASA Flight Medicine Clinic's electronic medical record and Longitudinal Survey of Astronaut Health were also reviewed. Using this work, a screening and management algorithm was created that takes into consideration the unique operational environment of spaceflight. Results: Renal stone screening and management guidelines for astronauts were created based on accepted standards of care, with consideration to the environment of spaceflight. In the proposed algorithm, all astronauts will receive a yearly screening ultrasound for renal calcifications, or mineralized renal material (MRM). Any areas of MRM, 3 millimeters or larger, are considered a positive finding. Three millimeters approaches the detection limit of standard ultrasound, and several studies have shown that any stone that is 3 millimeters or less has an approximately 95 percent chance of spontaneous passage. For mission-assigned astronauts, any positive ultrasound study is followed by low-dose renal computed tomography (CT) scan, and flexible ureteroscopy if CT is positive. Other specific guidelines were also created. Discussion: The term "MRM" is used to account for small areas of calcification that may be outside the renal collecting system, and allows objectivity without otherwise constraining the diagnostic and treatment process for potentially very small calcifications of uncertain

  18. Technical Approach for Determining Key Parameters Needed for Modeling the Performance of Cast Stone for the Integrated Disposal Facility Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Yabusaki, Steven B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Serne, R. Jeffrey [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rockhold, Mark L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wang, Guohui [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Westsik, Joseph H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-03-30

    Washington River Protection Solutions (WRPS) and its contractors at Pacific Northwest National Laboratory (PNNL) and Savannah River National Laboratory (SRNL) are conducting a development program to develop / refine the cementitious waste form for the wastes treated at the ETF and to provide the data needed to support the IDF PA. This technical approach document is intended to provide guidance to the cementitious waste form development program with respect to the waste form characterization and testing information needed to support the IDF PA. At the time of the preparation of this technical approach document, the IDF PA effort is just getting started and the approach to analyze the performance of the cementitious waste form has not been determined. Therefore, this document looks at a number of different approaches for evaluating the waste form performance and describes the testing needed to provide data for each approach. Though the approach addresses a cementitious secondary aqueous waste form, it is applicable to other waste forms such as Cast Stone for supplemental immobilization of Hanford LAW. The performance of Cast Stone as a physical and chemical barrier to the release of contaminants of concern (COCs) from solidification of Hanford liquid low activity waste (LAW) and secondary wastes processed through the Effluent Treatment Facility (ETF) is of critical importance to the Hanford Integrated Disposal Facility (IDF) total system performance assessment (TSPA). The effectiveness of cementitious waste forms as a barrier to COC release is expected to evolve with time. PA modeling must therefore anticipate and address processes, properties, and conditions that alter the physical and chemical controls on COC transport in the cementitious waste forms over time. Most organizations responsible for disposal facility operation and their regulators support an iterative hierarchical safety/performance assessment approach with a general philosophy that modeling provides

  19. Improving child and parenting outcomes following paediatric acquired brain injury: a randomised controlled trial of Stepping Stones Triple P plus Acceptance and Commitment Therapy.

    Science.gov (United States)

    Brown, Felicity L; Whittingham, Koa; Boyd, Roslyn N; McKinlay, Lynne; Sofronoff, Kate

    2014-10-01

    Persistent behavioural difficulties are common following paediatric acquired brain injury (ABI). Parents and families also experience heightened stress, psychological symptoms and burden, and there is evidence of a reciprocal relationship between parent and child functioning, which may be mediated by the adoption of maladaptive parenting practices. Despite this, there is currently a paucity of research in family interventions in this population. The aim of this study was to determine the efficacy of Stepping Stones Triple P: Positive Parenting Program (SSTP), with an Acceptance and Commitment Therapy (ACT) workshop, in improving child outcomes and parenting practices following paediatric ABI. Fifty-nine parents of children (mean age 7 years, SD 3 years, 1 month; 35 males, 24 females) with ABI (Traumatic injuries 58%, Tumour 17%, Encephalitis or meningitis 15%, Cardiovascular accident 7%, Hypoxia 3%) who were evidencing at least mild behaviour problems were randomly assigned to treatment or care-as-usual conditions over 10 weeks. Mixed-model repeated-measures linear regression analyses were conducted to compare conditions from pre- to postintervention on child behavioural and emotional functioning (Eyberg Child Behavior Inventory, Strengths and Difficulties Questionnaire) and dysfunctional parenting style (Parenting Scale). Assessment of maintenance of change was conducted at a 6-month follow-up. The trial was registered on Australian New Zealand Clinical Trials Registry (ID: ACTRN12610001051033, www.anzctr.org.au). Significant time-by-condition interactions were identified on number and intensity of child behaviour problems, child emotional symptoms and parenting laxness and overreactivity, indicating significant improvements in the treatment condition, with medium-to-large effect sizes. Most improvements were maintained at 6 months. Group parenting interventions incorporating Triple P and ACT may be efficacious in improving child and parenting outcomes following

  20. Estimation of bearing capacity of floating group of stone columns

    OpenAIRE

    Fattah, Mohammed Y.; Al-Neami, Mohammed A.; Shamel Al-Suhaily, Ahmed

    2017-01-01

    Stone column is one of the ground improvement techniques. This technique has a proven performance, short time schedule, durability, constructability and low costs. The stone column technique has been used as a method of reinforcement of soft ground over the past 30 years. The bearing capacity of the stone column still has high level of uncertainties because the existing formulas for the estimation of the bearing capacity are general and do not take into consideration the type of the stone col...

  1. Dietary supplementation with olive stone meal in growing rabbits

    Directory of Open Access Journals (Sweden)

    Gerolamo Xiccato

    2010-01-01

    Full Text Available Olive stone meal is a low-digested fibre source potentially useful in the prevention of digestive troubles in growing rabbit permitting a better balance of dietary fibre fractions. To evaluate its efficacy, three experimental diets containing 0, 3 or 6% olive stone meal were fed to 222 rabbits from weaning (28 d to slaughter (73 d. Olive stone inclusion increased the proportion of large dietary particles while did not affect growth performance, digestive physiology and carcass and meat quality. Due to optimum health status observed in all experimental groups, the preventive action of olive stone meal against the occurrence of digestive troubles was not proven.

  2. Nurse-Initiated Telephone Follow Up after Ureteroscopic Stone Surgery.

    Science.gov (United States)

    Tackitt, Helen M; Eaton, Samuel H; Lentz, Aaron C

    2016-01-01

    This article presents findings of a quality improvement (QI) project using the DMAIC (define, measure, analyze, improve, and control) model designed to decrease the rate of emergency department (ED) visits and nurse advice line calls after ureteroscopic stone surgery. Results indicated that nurse-initiated follow- up phone calls can decrease ED visits.

  3. Risk factors for recurrent symptomatic pigmented biliary stones after percutaneous transhepatic biliary extraction.

    Science.gov (United States)

    Kim, Dong Won; Lee, Sang Yun; Cho, Jin-Han; Kang, Myong Jin; Noh, Myung Hwan; Park, Byeong-Ho

    2010-07-01

    To evaluate risk factors for the recurrence of biliary stones after a percutaneous transhepatic biliary stone extraction. The procedures were performed on 339 patients between July 2004 and December 2008 (54 months). Medical records and images were retrospectively reviewed for 135 patients (mean age, 66.4 years; 83 men and 52 women) who had undergone follow-up for a mean of 13.2 months (range, 3-37 months). To evaluate risk factors for the recurrence of biliary stones, variables were evaluated with univariate and multivariate analyses. Variables included sex, age, stone location, number of stones, stone size, presence of a peripapillary diverticulum, application of antegrade sphincteroplasty, presence of a biliary stricture, largest biliary diameter before the procedure, and gallbladder status. Thirty-three of the 135 patients (24%) had recurrent symptomatic biliary stones and underwent an additional extraction. The mean time to recurrence was 17.2 months +/- 8.7. Univariate analysis of risk factors for recurrence of biliary stones demonstrated that location, number of stones, stone size, application of antegrade sphincteroplasty, presence of a biliary stricture, and biliary diameter were significant factors (P or =6; relative risk, 64.8; 95% confidence interval: 5.8, 717.6) and stone size (> or =14 mm; relative risk, 3.8; 95% confidence interval: 1.138, 13.231) were determined to be significant risk factors. The independent risk factors for recurrence of symptomatic biliary stones after percutaneous transhepatic biliary stone extraction were a stone size of at least 14 mm and the presence of at least six stones. Copyright 2010 SIR. Published by Elsevier Inc. All rights reserved.

  4. Calcium Stone Growth in Urine from Cystic Fibrosis Patients and Healthy Controls

    Science.gov (United States)

    McSorley, Anita; Jones, Andrew M.; Webb, A. Kevin; Rao, P. Nagaraj; Kavanagh, John P.

    2007-04-01

    Cystic fibrosis patients have an increased risk of renal stone disease. There is some evidence that this may be related to a different excretory pattern of stone risk factors, but an alternative hypothesis, that the urine of cystic fibrosis patients is deficient in urinary inhibitors of crystallization and stone formation has not been tested. Here we have grown calcium stones, in vitro, in the presence of urine from healthy controls and compared this with growth in the presence of urine from cystic fibrosis patients. A stone farm was used to grow twelve calcium stones simultaneously, firstly in artificial urine for about 200 hours and then in 90% whole human urine for another 500 hours. Six of the stones received urine from healthy controls and six received urine from adult cystic fibrosis patients. There were no significant differences in stone mass at any of the key time points or in the overall growth pattern (p>0.05) between stones destined for, or treated with, urine from CF patients and the controls. Human urine greatly inhibited stone growth in vitro but there was no difference in the growth rate in urine from healthy controls and CF patients. This refutes the hypothesis that a tendency for a higher prevalence of urinary stones in CF patients is related to a deficiency in inhibitory activity.

  5. Effect of Diuretics on Ureteral Stone Therapy with Extracorporeal Shock Wave Lithotripsy

    Directory of Open Access Journals (Sweden)

    Zomorrodi A

    2008-01-01

    Full Text Available To evaluate the effect of diuretics on ureteral stone fragmentation and clearance during therapy with extra corporeal shock wave lithotripsy (ESWL, we studied 87 patients with ureteral stone at different levels and treated with ESWL. The patients were randomized into two groups treated by standard ESWL; the treatment protocol included 3500 shock wave per patient in each session, energy of the shock in two groups was 13 to 9 kv per patient, and the number of sessions was 3 per patient. The first group included 43 patients who received only ESWL, while the second group of 44 patients received as well 40 mg of furosemide. Stone fragmentation rate was 81% and 93.1% and stone clearance rate was 68.2% and 88.4% for the first and the second groups, respectively. With diuretics, fragmentation was18.8% more in the middle ureteral stones, 16.9% more in the upper tract stones, and 5.4% more in the distal stones. Moreover, clearance of fragmented stones was 38%, 28%, 15.4% more at middle and upper and distal ureteral stone, respectively. We conclude that the stone fragmentation and clearance were higher with ESWL and diuretics than without diuresis. Diuresis is safe and has some advantage at increasing the effect of ESWL on ureteral stones especially the middle ureteral calculi.

  6. Dental pulp stone formation during orthodontic treatment: A ...

    African Journals Online (AJOL)

    2015-06-21

    Jun 21, 2015 ... the presence of dental pulp stone, gender, age, tooth type and arches. Results: Dental pulp ... primary and permanent dentition.[1] Dental pulp stones .... interpretation provided training to familiarize the other observer with the ...

  7. Analysis of natural stone block pavements in urban shared areas

    Directory of Open Access Journals (Sweden)

    Pablo Zoccali

    2018-06-01

    Full Text Available This paper analysed and verified an existing block stone pavement in an urban shared area. Fatigue and rutting verification was performed respectively for bound and unbound pavement materials using analytical curves available in the literature. The commercial finite element (FE software Abaqus® was used to calculate the response of the pavement when subjected to different loading, construction and geometrical configurations (i.e. type of analysis, shape and size of meshes, boundary conditions, and bonding contacts between the pavements layers. At the end of this study, a static model of a structure with hexahedral blocks having sides of 0.02 m, with full bonded layers and restrained horizontal displacements on the model sides, was implemented to evaluate the maximum tensile stress induced in a block when the load is applied at its centre. This analysis highlighted the need for rigorous criteria for a correct design, in order to avoid inappropriate and expensive use of road materials. Keywords: Block pavement, Commercial vehicle loads, Finite element model, Hexagonal Stone block, Pedestrian pavement, Shared area

  8. Pyramidal anchor stone from Baga waters of Goa, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Tripati, S.

    . Pyramidal anchor stones have an apex hole which goes up to the round hole, however Goa anchor stone has no such perforation, but, instead has a rectangular cutting on the apex. The anchor stone is compared with Greek pyramidal anchor stones, and probably...

  9. Preliminary comparison research for origin characteristics of Qingtian stone, Shoushan stone, Changhua chicken-blood stone and Balin stone%青田石、寿山石、昌化鸡血石和巴林石的产地特征初步比较研究

    Institute of Scientific and Technical Information of China (English)

    朱选民

    2011-01-01

    This paper preliminarily researches the origin characteristics of Qingtian stone, Shoushan stone,Changhua chicken-blood stone and Balin stone by means of X-ray powder diffraction and electron paramagnetic resonance and so on, and finds the differences in mineral composition, structure order degree, polymorph characteristics, occurrence state of Fe3+ and mechanism of coloration etc.%文章通过X射线粉晶衍射、电子顺磁共振等方法对青田石、寿山石、昌化鸡血石和巴林石的产地特征进行了初步研究,发现在矿物组成、有序度、多型特征、Fe3+的赋存状态和致色机理等方面存在差异.

  10. Comparison of Different Methods of Denim Stone Washing by Pumice Stone, Acid Cellulases and Neutral Cellulases

    Directory of Open Access Journals (Sweden)

    M. Montazer

    2007-10-01

    Full Text Available Denim is a casual garment normally used by young people and extremely influential in shaping the fashion industry. Among various garments, these garments are subjected to innovations. This work is an attempt to compare the different methods of stone washing using pumice stones, acid cellulases and neutral cellulases or in combination of these methods. The effects of different processing conditions on the garment are compared and reported. Color differences of samples are probed by reflective colorimeter on the front side as well as the backside and also the white pocket of the garment.The abrasion resistance, tensile strength and crease recovery angle of samples are also reported. The XRD spectra are used to calculate the crystalline degrees of the selected samples. Moreover, fiber surfaces of some treated samples have been observed by SEM. The results indicate that treatment of denim with pumice stone with equal weight of garment causes a small color differences. The addition of cellulases to the washing, however, accelerates the color fading. Also, lower staining observed on the white pocket when the garment was treated with cellulases. However, the neutralcellulases increase the garment fading and decrease the staining on the white pocket. It is also observed that pumice stone with cellulases damages the fabric surface, although it is of a minimal damage.

  11. Bladder stones in catheterized spinal cord-injured patients in Nigeria

    African Journals Online (AJOL)

    Objective: The objective was to determine the incidence of bladder stones in patients with spinal cord injury (SCI) and to assess if catheter encrustation or positive urinary culture of Proteus mirabilis is predictive of bladder stones. Background: Bladder stones are common urological complication in those with SCI managed ...

  12. Extracorporeal shock wave lithotripsy of intrahepatic stones with piezoelectric lithotriptor: in vitro study

    International Nuclear Information System (INIS)

    Choi, Byung Ihn; Yoon, Chong Hyun; Park, Yong Hyun; Han, Joon Koo; Yoon, Yong Bum; Shin, Yong Moon; Kim, Jin Q; Kim, Chu Wan; Han, Man Chung

    1992-01-01

    This study was designed to investigate effectiveness of fragmentation during lithotripsy using 103 intrahepatic stones collected from 10 patients, who had previously undergone biliary surgery. The size of each stone was measured and sonography was performed for the evaluation of the sonographic type of the stones. In vitro lithotripsy was performed on individual stones using piezoelectric lithotriptor to evaluate the fragmentation rate and average number of shock waves for fragmentation. Chemical analysis of each stone was done to determine chemical composition including calcium, bilirubin, and cholesterol. The size of the stones was from 5 mm to 20 mm in diameter. Sonographic type I (echo of whole stone with posterior acoustic shadow) was 68, and type II (are-like strong surface echo of stone with clear posterior acoustic shadow) was 35 in number. The majority (78%) of stones in group I (5-9 mm in diameter) showed sonographic type I characteristics, and 62% of stones in group 3 (larger than 15 mm in diameter) showed sonographic type II characteristics. There was a positive correlation between the size and sonographic type of stones. Fragmentation rates of stones were 100% in group I, 71.9% in group 2 (10-15 mm in diameter), 43.8% in group 3, respectively. Fragmentation rates of stones with sonographic type I and II were 91.2%, 65.7%, respectively. The average number of shock waves for partial and complete fragmentation was 2753 ± 4937 and 6219 ± 10133, respectively. There was a positive correlation between the number of shock waves for fragmentation and diameter of stones (r = 0.618, ρ < 0.05). There was no correlation between the number of shock waves for fragmentation and chemical composition of stones. In conclusion, the most important variable determining the degree of fragmentation of intrahepatic stones using ESWL is not their chemical composition but their size and sonographic characteristics

  13. Extracorporeal shock wave lithotripsy of intrahepatic stones with piezoelectric lithotriptor: in vitro study

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Byung Ihn; Yoon, Chong Hyun; Park, Yong Hyun; Han, Joon Koo; Yoon, Yong Bum; Shin, Yong Moon; Kim, Jin Q; Kim, Chu Wan; Han, Man Chung [Seoul National University, College of Medicine, Seoul (Korea, Republic of)

    1992-05-15

    This study was designed to investigate effectiveness of fragmentation during lithotripsy using 103 intrahepatic stones collected from 10 patients, who had previously undergone biliary surgery. The size of each stone was measured and sonography was performed for the evaluation of the sonographic type of the stones. In vitro lithotripsy was performed on individual stones using piezoelectric lithotriptor to evaluate the fragmentation rate and average number of shock waves for fragmentation. Chemical analysis of each stone was done to determine chemical composition including calcium, bilirubin, and cholesterol. The size of the stones was from 5 mm to 20 mm in diameter. Sonographic type I (echo of whole stone with posterior acoustic shadow) was 68, and type II (are-like strong surface echo of stone with clear posterior acoustic shadow) was 35 in number. The majority (78%) of stones in group I (5-9 mm in diameter) showed sonographic type I characteristics, and 62% of stones in group 3 (larger than 15 mm in diameter) showed sonographic type II characteristics. There was a positive correlation between the size and sonographic type of stones. Fragmentation rates of stones were 100% in group I, 71.9% in group 2 (10-15 mm in diameter), 43.8% in group 3, respectively. Fragmentation rates of stones with sonographic type I and II were 91.2%, 65.7%, respectively. The average number of shock waves for partial and complete fragmentation was 2753 {+-} 4937 and 6219 {+-} 10133, respectively. There was a positive correlation between the number of shock waves for fragmentation and diameter of stones (r = 0.618, {rho} < 0.05). There was no correlation between the number of shock waves for fragmentation and chemical composition of stones. In conclusion, the most important variable determining the degree of fragmentation of intrahepatic stones using ESWL is not their chemical composition but their size and sonographic characteristics.

  14. Ureteroscopy and stone lithotripsy with lithoclast: personal experience.

    Science.gov (United States)

    Leidi, G L; Berti, G L; Canclini, L; Giola, V; Maccaroni, A; Raimoldi, A; Veneroni, L; Bacchioni, A M

    1997-06-01

    Ureteroscopy has become a common technique in the diagnosis and treatment of ureteral pathologies, but this procedure is quite invasive and some complications have been reported in literature. In our Institute 49 patients underwent ureteroscopy and ballistic lithotripsy with lithoclast for ureteral stones. The stones were localized both in the middle and distal part of the ureter. We used a small caliber 7-8.5 Wolf ureteroscope. The treatments were performed under antibiotic prophylaxis. Direct access to the ureter without dilation of the meatus was obtained in 97.96% of patients. The stones were easily reached in 93.88% of the cases and satisfactory fragmentation was obtained in 90.7%. In 4 patients (9.3%) one or more large stone fragments escaped into the kidney, requiring the patients to be treated with ESWL. No major complications occurred: no ureteral perforations, no important bleeding and no severe or persistent infections. All patients were discharged in one to four days postoperatively. The authors conclude that ureteroscopy using small caliber instruments with Lithoclast is a safe and satisfactory alternative to ESWL in the treatment of ureteral stones.

  15. Percutaneous nephrolithotomy versus extracorporeal shock wave lithotripsy for moderate sized kidney stones.

    Science.gov (United States)

    Deem, Samuel; Defade, Brian; Modak, Asmita; Emmett, Mary; Martinez, Fred; Davalos, Julio

    2011-10-01

    To compare the outcomes of percutaneous nephrolithotomy (PNL) and extracorporeal shock wave lithotripsy (ESWL) for moderate sized (1-2 cm) upper and middle pole renal calculi in regards to stone clearance rate, morbidity, and quality of life. All patients diagnosed with moderate sized upper and middle pole kidney stones by computed tomography (CT) were offered enrollment. They were randomized to receive either ESWL or PNL. The SF-8 quality of life survey was administered preoperatively and at 1 week and 3 months postoperatively. Abdominal radiograph at 1 week and CT scan at 3 months were used to determine stone-free status. All complications and outcomes were recorded. PNL established a stone-free status of 95% and 85% at 1 week and 3 months, respectively, whereas ESWL established a stone-free status of 17% and 33% at 1 week and 3 months, respectively. Retreatment in ESWL was required in 67% of cases, with 0% retreatment in PNL. Stone location, stone density, and skin-to-stone distance had no impact on stone-free rates at both visits, irrespective of procedure. Patient-reported outcomes, including overall physical and mental health status, favored a better quality of life for patients who had PNL performed. PNL more often establishes stone-free status, has a more similar complication profile, and has similar reported quality of life at 3 months when compared with ESWL for moderate-sized kidney stones. PNL should be offered as a treatment option to all patients with moderate-sized kidney stones in centers with experienced endourologists. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Edge scour in current adjacent to stone covers

    DEFF Research Database (Denmark)

    Petersen, Thor Ugelvig; Sumer, B. Mutlu; Meyer, Knud Erik

    The present paper reports some early results of an experimental investigation of edge scour in currents. Two kinds of measurements are made (1) Particle Image Velocimetry (PIV) measurements of secondary currents that take place near a junction between the stone cover and the sand bed in a clear......-water experiment; and (2) scour measurements in actual scour experiment in the live-bed regime. The early results indicate that edge scour in a steady current propagating in-line with a stone layer is caused by the combined action of two effects; (1) Primary flow and (2) Secondary flow. The primary flow stirs up...... the sediment and puts into suspension, and the secondary flow carries it away from the junction between the stone layer and the sand bed, resulting in a scour hole forming adjacent to the toe of the stone layer....

  17. Ultrasonic propulsion of kidney stones: preliminary results of human feasibility study.

    Science.gov (United States)

    Bailey, Michael; Cunitz, Bryan; Dunmire, Barbrina; Paun, Marla; Lee, Franklin; Ross, Susan; Lingeman, James; Coburn, Michael; Wessells, Hunter; Sorensen, Mathew; Harper, Jonathan

    2014-09-03

    One in 11 Americans has experienced kidney stones, with a 50% average recurrence rate within 5-10 years. Ultrasonic propulsion (UP) offers a potential method to expel small stones or residual fragments before they become a recurrent problem. Reported here are preliminary findings from the first investigational use of UP in humans. The device uses a Verasonics ultrasound engine and Philips HDI C5-2 probe to generate real-time B-mode imaging and targeted "push" pulses on demand. There are three arms of the study: de novo stones, post-lithotripsy fragments, and the preoperative setting. A pain questionnaire is completed prior to and following the study. Movement is classified based on extent. Patients are followed for 90 days. Ten subjects have been treated to date: three de novo , five post-lithotripsy, and two preoperative. None of the subjects reported pain associated with the treatment or a treatment related adverse event, beyond the normal discomfort of passing a stone. At least one stone was moved in all subjects. Three of five post-lithotripsy subjects passed a single or multiple stones within 1-2 weeks following treatment; one subject passed two (1-2 mm) fragments before leaving clinic. In the pre-operative studies we successfully moved 7 - 8 mm stones. In four subjects, UP revealed multiple stone fragments where the clinical image and initial ultrasound examination indicated a single large stone.

  18. Changes in renal uptake of Tc-99m methylene diphosphonate (MDP) in stone-forming rats

    International Nuclear Information System (INIS)

    McAfee, J.G.; Thomas, F.D.; Roskopf, M.; Ritter, K.; Lyons, B.; Lilien, O.M.; Schoonmaker, J.E.

    1984-01-01

    A pyridoxine (vitamin B6)-deficient diet in rats was used as a model of early renal lithiasis to find out if stone-formers could be identified from control animals by differences in the biodistribution of Tc-99m MDP. The mean renal uptake of this agent at 3 hours was about 70% higher in test animals than in controls, but there was considerable overlap between the upper limits of the normal range and lower values in stone-formers. If these results were valid for humans, the metabolic abnormality in males with early stone-forming disease could not be identified with certainty by in vivo measurements of Tc-99m MDP renal uptake alone. However, the skeletal uptake of MDP in the stone-forming animals was depressed by 28 to 35%, compared with control rats. Consequently, the renal to skeletal MDP concentration ratio was invariably elevated in stone-formers beyond the 95 percentile normal range. Unexpectedly, 76% of the pyridoxine-deficient animals had a higher accumulation of MDP in the myocardium than the upper limit of the normal range. The pyridoxine-deficient diet induced no remarkable early changes in the biodistribution or renal clearance of I-131 Hippuran

  19. Endolithic phototrophs in built and natural stone.

    Science.gov (United States)

    Gaylarde, Christine C; Gaylarde, Peter M; Neilan, Brett A

    2012-08-01

    Lichens, algae and cyanobacteria have been detected growing endolithically in natural rock and in stone buildings in various countries of Australasia, Europe and Latin America. Previously these organisms had mainly been described in natural carbonaceous rocks in aquatic environments, with some reports in siliceous rocks, principally from extremophilic regions. Using various culture and microscopy methods, we have detected endoliths in siliceous stone, both natural and cut, in humid temperate and subtropical climates. Such endolithic growth leads to degradation of the stone structure, not only by mechanical means, but also by metabolites liberated by the cells. Using in vitro culture, transmission, optical and fluorescence microscopy, and confocal laser scanning microscopy, both coccoid and filamentous cyanobacteria and algae, including Cyanidiales, have been identified growing endolithically in the facades of historic buildings built from limestone, sandstone, granite, basalt and soapstone, as well as in some natural rocks. Numerically, the most abundant are small, single-celled, colonial cyanobacteria. These small phototrophs are difficult to detect by standard microscope techniques and some of these species have not been previously reported within stone.

  20. Process for altering the colour of hard stones

    International Nuclear Information System (INIS)

    Samoilovich, M.I.; Shaposhniko, A.A.; Turinge, A.P.; Vakhidov, S.A.; Nurullaev, Ergash.

    1981-01-01

    Process for altering the colour of hard stones and articles made with such stones, used in the jewellery trade, consisting in treating the hard stones in a neutron reactor and gamma particles accompanying them, whereby the treatment is performed with fast neutrons of at least 0.5 MeV, at integral doses of 5x10 15 to 1x10 18 neutrons/cm 2 , and gamma radiations, at integral doses of 5x10 6 to 1x10 9 R, at temperatures under 300 0 C [fr

  1. Scanning electron microscopy of real and artificial kidney stones before and after Thulium fiber laser ablation in air and water

    Science.gov (United States)

    Hardy, Luke A.; Irby, Pierce B.; Fried, Nathaniel M.

    2018-02-01

    We investigated proposed mechanisms of laser lithotripsy, specifically for the novel, experimental Thulium fiber laser (TFL). Previous lithotripsy studies with the conventional Holmium:YAG laser noted a primary photothermal mechanism (vaporization). Our hypothesis is that an additional mechanical effect (fragmentation) occurs due to vaporization of water in stone material from high absorption of energy, called micro-explosions. The TFL irradiated calcium oxalate monohydrate (COM) and uric acid (UA) stones, as well as artificial stones (Ultracal30 and BegoStone), in air and water environments. TFL energy was varied to determine the relative effect on the ablation mechanism. Scanning electron microscopy (SEM) was used to study qualitative and characteristic changes in surface topography with correlation to presumed ablation mechanisms. Laser irradiation of stones in air produced charring and melting of the stone surface consistent with a photothermal effect and minimal fragmentation, suggesting no mechanical effect from micro-explosions. For COM stones ablated in water, there was prominent fragmentation in addition to recognized photothermal effects, supporting dual mechanisms during TFL lithotripsy. For UA stones, there were minimal photothermal effects, and dominant effects were mechanical. By increasing TFL pulse energy, a greater mechanical effect was demonstrated for both stone types. For artificial stones, there was no significant evidence of mechanical effects. TFL laser lithotripsy relies on two prominent mechanisms for stone ablation, photothermal and mechanical. Water is necessary for the mechanical effect which can be augmented by increasing pulse energy. Artificial stones may not provide a predictive model for mechanical effects during laser lithotripsy.

  2. Analysis of kidney stones by PIXE and RBS techniques

    Energy Technology Data Exchange (ETDEWEB)

    Alkofai, M M [Physics Dept., Yarmouk University, Irbid, (Jordan); Hallak, A B [Research Institute, King Fahd University of Petroleum and Minerals, Dhahran 31261, (Saudi Arabia)

    1995-10-01

    Human kidney stones were analyzed by PIXE and RBS techniques using 2 MeV He{sup ++} beam. The stones were found to contain the elements: C, N, O, F, Na, Mg, Si, P, S, Cl, K, Ca, Fe and Br. Results obtained by PIXE agree with the results obtained by RBS within experimental errors. A Mechanism for the formation of the kidney stones is suggested. 3 figs., 1 tab.

  3. Analysis of kidney stones by PIXE and RBS techniques

    International Nuclear Information System (INIS)

    Alkofai, M.M.; Hallak, A.B.

    1995-01-01

    Human kidney stones were analyzed by PIXE and RBS techniques using 2 MeV He ++ beam. The stones were found to contain the elements: C, N, O, F, Na, Mg, Si, P, S, Cl, K, Ca, Fe and Br. Results obtained by PIXE agree with the results obtained by RBS within experimental errors. A Mechanism for the formation of the kidney stones is suggested. 3 figs., 1 tab

  4. The Cost-Effectiveness of Treatment Modalities for Ureteral Stones

    Directory of Open Access Journals (Sweden)

    Justin Ji-Yuen Siu MD

    2016-10-01

    Full Text Available Additional intervention and medical treatment of complications may follow the primary treatment of a ureteral stone. We investigated the cost of the treatment of ureteral stone(s within 45 days after initial intervention by means of retrospective analysis of the National Health Insurance Research Database of Taiwan. All patients of ages ≥20 years diagnosed with ureteral stone(s( International Classification of Diseases, Ninth Revision, Clinical Modification/ICD-9-CM: 592.1 from January 2001 to December 2011 were enrolled. We included a comorbidity code only if the diagnosis appeared in at least 2 separate claims in a patient’s record. Treatment modalities (code included extracorporeal shock-wave lithotripsy (SWL; 98.51, ureteroscopic lithotripsy (URSL; 56.31, percutaneous nephrolithotripsy (PNL; 55.04, (open ureterolithotomy (56.20, and laparoscopy (ie, laparoscopic ureterolithotomy; 54.21. There were 28 513 patients with ureteral stones (13 848 men and 14 665 women in the randomized sample of 1 million patients. The mean cost was 526.4 ± 724.1 United States Dollar (USD. The costs of treatment were significantly increased in patients with comorbidities. The costs of treatment among each primary treatment modalities were 1212.2 ± 627.3, 1146.7 ± 816.8, 2507.4 ± 1333.5, 1533.3 ± 1137.1, 2566.4 ± 2594.3, and 209.8 ± 473.2 USD in the SWL, URSL, PNL, (open ureterolithotomy, laparoscopy (laparoscopic ureterolithotomy, and conservative treatment group, respectively. In conclusion, URSL was more cost-effective than SWL and PNL as a primary treatment modality for ureteral stone(s when the possible additional costs within 45 days after the initial operation were included in the calculation.

  5. Medical expulsive treatment of distal ureteral stone using tamsulosin

    International Nuclear Information System (INIS)

    Ahmad, H.; Azim, W.; Akmal, M.; Murtaza, B.

    2015-01-01

    Many minimally invasive interventional techniques as well as expectant treatments exist for the management of lower ureteric calculi. This study was conducted to evaluate the efficacy of tamsulosin as an expulsive pharmacologic therapy for the treatment of distal ureteral stone. Methods: This randomized control trial included 100 patients over 18 years of age with stone Size = 8mm in distal 1/3 of ureter. Patients were randomly assigned into two groups (A and B). Group A Patients were given Capsule Tamsulosin 0.4 mg, 1 daily up to 4 weeks while group B patients were given placebo, 1 Capsule daily up to 4 weeks. The primary endpoint was expulsion rate. A written informed consent was taken from all the patients. Expulsion time, need for analgesics, need for hospitalization and drug side effects were secondary endpoints. Results: A total of 49 patients in group A and 48 patients in group B reported back, therefore 97 out of 100 patients were evaluated. Mean age of the patients was 36.34 years (range 18-57 years). Mean stone size was 5.78 mm (range 4-8 mm) in greatest dimension. A stone expulsion rate of 85.71% (42 patients) was noted in group A and 54.20% (26 patients) in group B. Group A revealed a statistically significant advantage in term of stone expulsion rate (p=0.032). Considering expulsion time in days group A showed statistically significant advantage (p=0.015). Regarding age, sex, stone size and stone lateralization (right/left), there was no significant difference between the group A and B. No drug side effects were noted in both the groups. Conclusion: By using tamsulosin a higher stone expulsion rates can be achieved in a shorter time. More randomized control trials are required to establish tamsulosin as a standard medical expulsive treatment for small distal ureteric calculus. (author)

  6. Extended Leach Testing of Simulated LAW Cast Stone Monoliths

    Energy Technology Data Exchange (ETDEWEB)

    Serne, R. Jeffrey [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Westsik, Joseph H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Williams, Benjamin D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jung, H. B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wang, Guohui [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-07-09

    This report describes the results from long-term laboratory leach tests performed at Pacific Northwest National Laboratory (PNNL) for Washington River Protection Solutions (WRPS) to evaluate the release of key constituents from monoliths of Cast Stone prepared with four simulated low-activity waste (LAW) liquid waste streams. Specific objectives of the Cast Stone long-term leach tests described in this report focused on four activities: 1. Extending the leaching times for selected ongoing EPA-1315 tests on monoliths made with LAW simulants beyond the conventional 63-day time period up to 609 days reported herein (with some tests continuing that will be documented later) in an effort to evaluate long-term leaching properties of Cast Stone to support future performance assessment activities. 2. Starting new EPA-1315 leach tests on archived Cast Stone monoliths made with four LAW simulants using two leachants (deionized water [DIW] and simulated Hanford Integrated Disposal Facility (IDF) Site vadose zone pore water [VZP]). 3. Evaluating the impacts of varying the iodide loading (starting iodide concentrations) in one LAW simulant (7.8 M Na Hanford Tank Waste Operations Simulator (HTWOS) Average) by manufacturing new Cast Stone monoliths and repeating the EPA-1315 leach tests using DIW and the VZP leachants. 4. Evaluating the impacts of using a non-pertechnetate form of Tc that is present in some Hanford tanks. In this activity one LAW simulant (7.8 M Na HTWOS Average) was spiked with a Tc(I)-tricarbonyl gluconate species and then solidified into Cast Stone monoliths. Cured monoliths were leached using the EPA-1315 leach protocol with DIW and VZP. The leach results for the Tc-Gluconate Cast Stone monoliths were compared to Cast Stone monoliths pertechnetate.

  7. In vitro CT evaluation of intrahepatic stones: correlation with chemical composition

    International Nuclear Information System (INIS)

    Kim, Young Jun; Han, Joon Koo; Jeong, Jun Yong; Lee, Kyoung Ho; Kim, Se Hyung; Kim, Young Il; Lee, Jeong Min; Choi, Byung Ihn; Park, Youn-Chan; Kim, Sun-Whe

    2005-01-01

    Objective: To describe in vitro CT features of intrahepatic stones and to correlate CT attenuation with chemical composition. Materials and methods: Of the patients who underwent choledochoscopic intrahepatic stone removal between 1998 and 2001, 54 patients with stones larger than 3 mm were enrolled in this study. In each case, a chemical compositional analysis was performed to determine calcium, cholesterol, total bilirubin, and inorganic phosphorus compositions. The three largest stones obtained from each patient were imaged by CT. CT attenuation numbers were measured in the center images of each stone by drawing free-hand region of interest (ROI). The measured CT attenuation numbers were correlated with their chemical composition. Also, CT attenuation numbers of stones were compared with that of the liver on non-contrast CT (50-70 HU). Results: Stone size ranged from 3.1 to 10.5 mm (mean ± S.D.: 6.0 ± 1.4). The CT attenuation numbers (HU) of stones ranged from 36.4 to 410.19 (mean ± S.D.: 94.6 ± 49.9). CT numbers of stones were below 70 HU in 11 patients (20.4%), and below 90 HU in 33 patients (59.3%). The chemical analysis data of the stones were as follows: calcium (0.5-6.5 wt.%; mean ± S.D., 2.6 ± 1.4), total bilirubin (0.45-24.4 wt.%; 13.1 ± 6.2), cholesterol (5.4-73.9 wt.%; 29.3 ± 17.4), phosphorus (0.1-1.2 wt.%; 0.6 ± 0.3), and non-soluble residue (17.6-85.4 wt.%; 57.0 ± 22.6). There was a weak but significant correlation between calcium composition and CT attenuation (r = 0.38, P 0.01; total bilirubin, r = 0.05, P > 0.01; phosphorus, r = 0.01, P > 0.01). Conclusion: On non-contrast CT, intrahepatic stones would not be hyperattenuating with respect to liver parenchyma in about one fifth of patients. The CT attenuation of stones correlates with calcium and does not correlate with any other chemical composition

  8. The study on the factors for detection of renal stone on ultrasound

    International Nuclear Information System (INIS)

    Sim, Hyun Sun; Jung, Hong Ryang; Lim, Cheong Hwan

    2006-01-01

    Renal stones are common and typically arise within the collecting system. The renal sinus are contains the collection system, the renal vessels, lymphatcs, fat, and fibrous tissue. Because of the compression of all the large echoes in signal processing, the echo from the renal stone generally cannot be distinguished from large echoes emanating from normal structures of the renal sinus. Use of ultrasonography has been difficult for detecting small renal stone without posterior shadowing and chemical composition of stone. The aim of study was measuring for posterior acoustic shadowing to a stone for various scan parameter and it examines a help in renal stone diagnosis. The stone was place on sponge examined in a water bath with a 3.5 MHz or 7.5 HMz transducer (LOGIQ 400, USA). First, tested a variety of gain. Second, tested a variety of dynamic range. Third, tested a variety of focal zone. Fourth, measuring of the echo level for low and high frequency for depth. 1) Average echo level was 98 for low total gain (10 dB) and was 142 for high total gain (40 dB). Posterior acoustic shadowing of renal stone was clear for low gain. 2) Average echo level was 129 for low dynamic range (42 dB) and was 101 for high dynamic range (72 dB). Posterior acoustic shadowing of renal stone was clear for high dynamic range. 3) When stone is in focal zone of transducer, definite posterior acoustic shadow is identified. 4) Stone was clear appeared for high frequency (7.5 MHz) than low frequency (3.5 MHz) and it is not distorted. The demonstration of an posterior acoustic shadow of renal stone dependents on several technical factors such as gain, dynamic range, focus, and frequency. This various factors are a help in renal stone diagnosis

  9. 21 CFR 876.4650 - Water jet renal stone dislodger system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Water jet renal stone dislodger system. 876.4650... (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4650 Water jet renal stone dislodger system. (a) Identification. A water jet renal stone dislodger system is a device used to...

  10. The Incidence of Complications in Single-stage Endoscopic Stone Removal for Patients with Common Bile Duct Stones: A Propensity Score Analysis.

    Science.gov (United States)

    Saito, Hirokazu; Kadono, Yoshihiro; Kamikawa, Kentaro; Urata, Atsushi; Imamura, Haruo; Matsushita, Ikuo; Kakuma, Tatsuyuki; Tada, Shuji

    2018-02-15

    Objective Single-stage endoscopic stone removal for choledocholithiasis is an advantageous approach because it is associated with a shorter hospital stay; however, few studies have reported the incidence of complications related to this procedure in detail. The aim of this study was to examine the incidence of complications and efficacy of this procedure. Methods This retrospective study investigated the incidence of complications in 345 patients with naive papilla who underwent therapeutic endoscopic retrograde cholangiopancreatography (ERCP) for choledocholithiasis at three institutions between April 2014 and March 2016 by a propensity score analysis. The efficacy of single-stage endoscopic stone removal was assessed based on a hospital stay of within 7 days and the number of ERCP attempts. Results Among 114 patients who underwent single-stage endoscopic stone removal, 15 patients (13.2%) experienced complications. Among the remaining 231 patients in the two-stage endoscopic stone removal group, complications were observed in 17 patients (7.4%). The propensity score analysis, which was adjusted for confounding factors, revealed that single-stage endoscopic stone removal was not a significant risk factor for complications (p=0.52). In patients in whom >10 min was required for deep cannulation, single-stage endoscopic stone removal was not a significant risk factor for complications in the propensity score analysis (p=0.37). In the single-stage group, the proportion of patients with a hospital stay of within 7 days was significantly higher and the number of ERCP attempts was significantly lower in comparison to the two-stage group (p <0.0001 and <0.0001, respectively). Conclusion Single-stage endoscopic stone removal did not increase the incidence of complications associated with ERCP and was effective for reducing the hospital stay and the number of ERCP attempts.

  11. The natural outcome of melamine-induced bladder stones with bladder epithelial hyperplasia after the withdrawal of melamine in mice.

    Science.gov (United States)

    Ren, Shu-Ting; Xu, Chang-Fu; Du, Yun-Xia; Gao, Xiao-Li; Sun, Ying; Jiang, Yi-Na

    2012-07-01

    The natural outcome of melamine-induced bladder stones (cystoliths) with bladder epithelial hyperplasia (BEH) after melamine withdrawn is unclear. Using an ideal dual-model system, three experiments were conducted in BALB/c mice. Each experiment included a control, model 1 and model 2 groups. The mice were fed a regular diet in controls or a 9373 ppm melamine diet in models, and the first day was designated as dosing day 1. The melamine diet was then replaced by the regular diet in the model 2 groups, and the first day was designated as post-dosing day 1. On dosing days 12, 35 and 49, the incidence of cystoliths and diffusely active BEH was 8/8 in the mice of three model 1 groups. On post-dosing days 1, 4 and 8, in the mice of three model 2 groups, the incidence of cystoliths was 2/8, 0/8 and 1/8, respectively, and the progressive regression of BEH was observed. In conclusion, both the stones and BEH have the natural property of rapid development and rapid regression, and melamine withdrawn plays a key role in the stone dissolution-discharge necessary for BEH regression. BEH may be reversible after the discharge of the stones. The conventionally conservative therapy is thus reasonable. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. The Civil Palaces in Gravina street, Alicante: building stones and salt weathering

    OpenAIRE

    Louis, M.; García del Cura, M. A.; Spairani, Y.; de Blas, D.

    2001-01-01

    This paper presents a study into the architecture and construction of the 18th Century Civil Palaces located in Gravina street (Provincial Museum of Fine Arts of Alicante), the building stones used and the mineral related decay processes that these materials have suffered. The original building stones and other stones used in subsequent restorations in these Civil Palaces are bioclastic limestones and/or calcarenites (San Julian Stone and Bateig Stone). Campello st...

  13. Flow-based market coupling. Stepping stone towards nodal pricing?

    International Nuclear Information System (INIS)

    Van der Welle, A.J.

    2012-07-01

    For achieving one internal energy market for electricity by 2014, market coupling is deployed to integrate national markets into regional markets and ultimately one European electricity market. The extent to which markets can be coupled depends on the available transmission capacities between countries. Since interconnections are congested from time to time, congestion management methods are deployed to divide the scarce available transmission capacities over market participants. For further optimization of the use of available transmission capacities while maintaining current security of supply levels, flow-based market coupling (FBMC) will be implemented in the CWE region by 2013. Although this is an important step forward, important hurdles for efficient congestion management remain. Hence, flow based market coupling is compared to nodal pricing, which is often considered as the most optimal solution from theoretical perspective. In the context of decarbonised power systems it is concluded that advantages of nodal pricing are likely to exceed its disadvantages, warranting further development of FBMC in the direction of nodal pricing.

  14. Stone anchors of India: Findings, classification and significance.

    Digital Repository Service at National Institute of Oceanography (India)

    Tripati, S.

    Various types of stone anchors have been observed during inshore and offshore explorations along the east and west coasts of India. The earliest stone anchors of India have been recorded from the Harappan sites (3rd millennium BC), but their shape...

  15. Single-stage laparoscopic common bile duct exploration and cholecystectomy versus two-stage endoscopic stone extraction followed by laparoscopic cholecystectomy for patients with concomitant gallbladder stones and common bile duct stones: a randomized controlled trial.

    Science.gov (United States)

    Bansal, Virinder Kumar; Misra, Mahesh C; Rajan, Karthik; Kilambi, Ragini; Kumar, Subodh; Krishna, Asuri; Kumar, Atin; Pandav, Chandrakant S; Subramaniam, Rajeshwari; Arora, M K; Garg, Pramod Kumar

    2014-03-01

    The ideal method for managing concomitant gallbladder stones and common bile duct (CBD) stones is debatable. The currently preferred method is two-stage endoscopic stone extraction followed by laparoscopic cholecystectomy (LC). This prospective randomized trial compared the success and cost effectiveness of single- and two-stage management of patients with concomitant gallbladder and CBD stones. Consecutive patients with concomitant gallbladder and CBD stones were randomized to either single-stage laparoscopic CBD exploration and cholecystectomy (group 1) or endoscopic retrograde cholangiopancreatography (ERCP) for endoscopic extraction of CBD stones followed by LC (group 2). Success was defined as complete clearance of CBD and cholecystectomy by the intended method. Cost effectiveness was measured using the incremental cost-effectiveness ratio. Intention-to-treat analysis was performed to compare outcomes. From February 2009 to October 2012, 168 patients were randomized: 84 to the single-stage procedure (group 1) and 84 to the two-stage procedure (group 2). Both groups were matched with regard to demographic and clinical parameters. The success rates of laparoscopic CBD exploration and ERCP for clearance of CBD were similar (91.7 vs. 88.1 %). The overall success rate also was comparable: 88.1 % in group 1 and 79.8 % in group 2 (p = 0.20). Direct choledochotomy was performed in 83 of the 84 patients. The mean operative time was significantly longer in group 1 (135.7 ± 36.6 vs. 72.4 ± 27.6 min; p ≤ 0.001), but the overall hospital stay was significantly shorter (4.6 ± 2.4 vs. 5.3 ± 6.2 days; p = 0.03). Group 2 had a significantly greater number of procedures per patient (p gallbladder and CBD stones had similar success and complication rates, but the single-stage strategy was better in terms of shorter hospital stay, need for fewer procedures, and cost effectiveness.

  16. Extracorporeal shock wave lithotripsy for gallbladder stones - an experimental and clinical study -

    International Nuclear Information System (INIS)

    Kim, Kun Sang; Park, Sil Moo; Lee, Jung Hyo; Kim, Young Goo; Song, Kounn Sik; Lee, Kwan Seh; Lee, Jong Beum; Kim, Sang Joon; Chang, Sun Taik

    1988-01-01

    Although many alternative treatment technics have been proposed recently for gallstone to substitute cholecystectomy, the extracorporeal shock wave lithotripsy (ESWL) for gallbladder stones has rarely been tried. We have carried out a series of experiments to evaluate how effective the ESWL for gallbladder stones in and how safe this procedure is. At first, in vitro shock were application was carried out to 10 gallbladder stones which were obtained from human gallbladder. Secondly, gallbladder stones were implanted to canine gallbladder and treated with shock wave. Lastly, a total of 41 volunteers with confirmed gallbladder stones were treated with shock wave and combined oral administration of ursodeoxycholic acid. In the in vitro experiment, all of the 10 gallstones were fragmented with variable firing rates and duration. In animal experiment, the implanted stones were successfully fragmented and the organs included in the pathway of shock wave were proved to be intact histologically. In human study, complete disappearance of gallstones was noted in 78.6% of patients with single radiolucent gallbladder stones, smaller than 2.5cm in the longest diameter. Two patients underwent cholecystectomy after ESWL due to sudden colic attack. One patient had experienced an episode of mild transient obstructive jaundice. It may be concluded that the ESWL for gallbladder stones is an effective and safe method of treatment of gallbladder stones in the selected cases, for example, small radiolucent stones, and the further study is needed to establish improved technology of the ESWL for gallbladder stones.

  17. Extracorporeal shock wave lithotripsy for gallbladder stones - an experimental and clinical study -

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kun Sang; Park, Sil Moo; Lee, Jung Hyo; Kim, Young Goo; Song, Kounn Sik; Lee, Kwan Seh; Lee, Jong Beum; Kim, Sang Joon; Chang, Sun Taik [Chung-Ang University College of Medicine, Seoul (Korea, Republic of)

    1988-08-15

    Although many alternative treatment technics have been proposed recently for gallstone to substitute cholecystectomy, the extracorporeal shock wave lithotripsy (ESWL) for gallbladder stones has rarely been tried. We have carried out a series of experiments to evaluate how effective the ESWL for gallbladder stones in and how safe this procedure is. At first, in vitro shock were application was carried out to 10 gallbladder stones which were obtained from human gallbladder. Secondly, gallbladder stones were implanted to canine gallbladder and treated with shock wave. Lastly, a total of 41 volunteers with confirmed gallbladder stones were treated with shock wave and combined oral administration of ursodeoxycholic acid. In the in vitro experiment, all of the 10 gallstones were fragmented with variable firing rates and duration. In animal experiment, the implanted stones were successfully fragmented and the organs included in the pathway of shock wave were proved to be intact histologically. In human study, complete disappearance of gallstones was noted in 78.6% of patients with single radiolucent gallbladder stones, smaller than 2.5cm in the longest diameter. Two patients underwent cholecystectomy after ESWL due to sudden colic attack. One patient had experienced an episode of mild transient obstructive jaundice. It may be concluded that the ESWL for gallbladder stones is an effective and safe method of treatment of gallbladder stones in the selected cases, for example, small radiolucent stones, and the further study is needed to establish improved technology of the ESWL for gallbladder stones.

  18. Stone clearance after extracorporeal shockwave lithotripsy in patients with solitary pure calcium oxalate stones smaller than 1.0 cm in the proximal ureter, with special reference to monohydrate and dihydrate content.

    Science.gov (United States)

    Ichiyanagi, Osamu; Nagaoka, Akira; Izumi, Takuji; Kawamura, Yuko; Tsukigi, Masaaki; Ishii, Tatsuya; Ohji, Hiroshi; Kato, Tomoyuki; Tomita, Yoshihiko

    2013-04-01

    The aim of this study was to assess stone-free rates following extracorporeal shockwave lithotripsy (ESWL) of pure calcium oxalate (CaOx) stones in the proximal ureter. The investigators retrospectively examined 53 patients with 5-10 mm pure CaOx stones in the proximal ureter from the medical archives of 593 consecutive patients treated with ESWL. The compositions of calcium oxalate monohydrate (COM) and dihydrate (COD) in a given stone were determined by infrared spectrometry. Stone size, attenuation number and stone-to-skin distance (SSD) were measured using plain radiography and computed tomography (CT). ESWL success was evaluated by stone-free status after the first single session. On average, calculi were 8.0 × 5.3 mm in size, with an SSD of 11.0 cm. The mean CT attenuation value was 740.1 HU. Attenuation numbers correlated significantly with stone diameter (r = 0.49), but had no correlation with the stone content of COM or COD. A negative correlation was observed between COM and COD content (r = -0.925). With regard to patients' physical characteristics and COM and COD content, no differences were found between study subgroups with stone-free and residual status (n = 38 and 15, respectively). There were also no differences in clinical features between patient subgroups with COM- or COD-predominant stones (n = 22 and 31, respectively). The findings indicated that the differences in COM and COD content of CaOx stones had no impact on stone clearance after ESWL and that a favorable stone-free rate of the stones treated with ESWL may be achieved independently of CaOx hydration.

  19. Effect of blind treatment on stone disease.

    Science.gov (United States)

    Fazil Marickar, Y M; Salim, Abiya; Vijay, Adarsh

    2010-06-01

    Most of the drugs administered to stone patients appear to be inappropriate and doing more harm than good to the patients. The objective of this paper is to identify the prevalence of blind chemotherapy among the stone patients and find out the real indication for the drugs administered. Patients who attended the stone clinic for the first time were interviewed to find out what drugs they had been taking before the attendance at the stone clinic. 350 patients consuming specific drugs relevant to stone formation at least for a period of 15 days were selected for a detailed assessment. The type of drug consumed, the dose, the duration, the side effects, compliance rate and effect on stone disease were assessed. The biochemical profile of the patients was assessed to identify the role of the therapeutic modalities utilised. Conclusions regarding the utility of drugs in the process of stone formation were made. The values were compared with those of patients not on medication and considering laboratory standards. Of the 350 patients studied, 96 patients were consuming potassium citrate in different doses, 50 were consuming allopurinol, 44 cystone, 27 potassium citrate + magnesium, 25 calcury, 24 rowatinex, 21 ayurvedic drugs, 17 dystone, 17 homeopathic medicines and 17 other drugs. The longest duration of compliance was for cystone-2.5 years. All other drugs were stopped by the patients themselves due to recurrence of symptoms. As much as 93% of the patients did not feel that there was any significant relief of symptoms. The side effects which prompted the patients to stop medicine were gastro intestinal upset, particularly with potassium citrate, rowatinex and potassium citrate + magnesium combination. The relevant biochemical changes noted were increased urinary citrate levels in patients consuming potassium citrate alone or in combination with magnesium. Serum uric acid was within normal limits in patients consuming allopurinol. Urine uric acid levels were also

  20. Regional and detailed research studies for stone resources in Korea

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-01

    This report consists of 6 subjects. 1) A study on the potentiality of building stone development from granite mass within Pocheon area, Kyeonggi Province. 2) The research on the variance of color and glossiness by means of Weather-Ometer. 3) Regional research studies on granites in Gimje-Yeonggwang area. 4) A study on the industrialization of building stones and industrial stone crafts - Study on the causes of stone weathering. 5) Borehole radar survey at the granite quarry mine, Pocheon, Kyounggi province. 6) Borehole radar diffraction tomography. (author). refs., tabs., figs.

  1. Population-based estimate of urinary stones from Ballabgarh, northern India.

    Science.gov (United States)

    Lohiya, Ayush; Kant, Shashi; Kapil, Arti; Gupta, Sanjeev Kumar; Misra, Puneet; Rai, Sanjay K

    2017-01-01

    Stones in the urinary tract are a common condition but there is paucity of data on their population-based estimates in India. We describe our findings of the burden of urinary stones during a cross-sectional study with another primary goal. We conducted the study at Ballabgarh Health and Demographic Surveillance System, Haryana, among residents aged 18 years or above. We used simple random sampling to enrol participants. Self-reported history of urinary stones was elicited through an interview schedule. Results of the descriptive analysis were described as proportions with 95% confidence intervals (CI) or as mean wherever applicable. Bivariate analysis was done using t-test and chi-square test as applicable. The response rate for our study was 86.6%; lifetime prevalence (95% CI) of urinary stones was 7.9% (5.7, 10.8). In a majority of participants, urinary stones were diagnosed at an age of 20-40 years (55.9%), mostly by an ultrasonography examination (94.1%). A high burden of urinary stones is indicated in the working-age population in northern India at the community level. Untreated urinary stones can lead to an acute emergency (colic) or may have long-term adverse consequences, e.g. hydronephrosis, which have implications for the healthcare delivery system.

  2. The History of Urinary Stones: In Parallel with Civilization

    Directory of Open Access Journals (Sweden)

    Ahmet Tefekli

    2013-01-01

    Full Text Available The roots of modern science and history of urinary stone disease go back to the Ancient Egyptians and Mesopotamia. Hippocrates defined the symptoms of bladder stones. The first recorded details of “perineal lithotomy” were those of Cornelius Celsus. Ancient Arabic medicine was based mainly on classical Greco-Roman works. Interestingly, the Fourth Lateran Council in 1215 forbade physicians from performing surgical procedures, as contact with blood or body fluids was viewed as contaminating to men. With Renaissance new procedures could be tried on criminals. The first recorded suprapubic lithotomy was carried out by Pierre Franco in 1561. In 1874, Bigelow developed a lithotrite, which was introduced into the bladder under anaesthesia (called as “litholopaxy”. Young was the first to report ureteroscopy (1929. With advances in intracorporeal lithotripsy techniques, ureteroscopy became the treatment of choice for ureteric stones. In 1976, Fernstrom and Johannson established percutaneous access to remove a renal stone. However, with the introduction of the first extracorporeal shock wave machine in 1980, a dramatic change in stone management was observed. Civilization in parallel with scientific developments has brought us to a point where we try not to “cut” our patients for stone disease, as Hippocrates admonishes, but rather manage them with minimal invasive alternatives.

  3. A pilot study of the effect of sodium thiosulfate on urinary lithogenicity and associated metabolic acid load in non-stone formers and stone formers with hypercalciuria.

    Directory of Open Access Journals (Sweden)

    Onyeka W Okonkwo

    Full Text Available BACKGROUND AND OBJECTIVES: Sodium thiosulfate (STS reduced calcium stone formation in both humans and genetic hypercalciuric stone forming (GHS rats. We sought to measure urine chemistry changes resulting from STS administration in people. DESIGN SETTING PARTICIPANTS MEASUREMENTS: STS was given to healthy and hypercalciuric stone forming adults. Five normal non-stone forming adults (mean age 33 years, and 5 people with idiopathic hypercalciuria and calcium kidney stones (mean age 66 years participated. Two baseline 24-hour urine collections were performed on days 2 and 3 of 3 days of self-selected diets. Subjects then drank STS 10 mmol twice a day for 7 days and did urine collections while repeating the self-selected diet. Results were compared by non-parametric Wilcoxon signed rank test. The primary outcome was the resulting change in urine chemistry. RESULTS: STS administration did not cause a significant change in urinary calcium excretion in either group. In both groups, 24 hour urinary ammonium (P = 0.005 and sulfate excretion (P = 0.007 increased, and urinary pH fell (P = 0.005; citrate excretion fell (P<0.05 in hypercalciuric participants but not in non-stone formers. Among stone formers with hypercalciuria, 3 of 5 patients had measurement of serum HCO3 concentration after the STS period: it did not change. The net effect was an increase in supersaturation of uric acid, and no change in supersaturation of calcium oxalate or calcium phosphate. CONCLUSIONS: The basis for studies demonstrating that STS prevented stones in rats and people was not reflected by the changes in urine chemistry reported here. Although serum HCO3 did not change, urine tests suggested an acid load in both non-stone forming and hypercalciuric stone-forming participants. The long term safety of STS needs to be determined before the drug can be tested in humans for long-term prevention of stone recurrence.

  4. STEP - Product Model Data Sharing and Exchange

    DEFF Research Database (Denmark)

    Kroszynski, Uri

    1998-01-01

    During the last fifteen years, a very large effort to standardize the product models employed in product design, manufacturing and other life-cycle phases has been undertaken. This effort has the acronym STEP, and resulted in the International Standard ISO-10303 "Industrial Automation Systems...... - Product Data Representation and Exchange", featuring at present some 30 released parts, and growing continuously. Many of the parts are Application Protocols (AP). This article presents an overview of STEP, based upon years of involvement in three ESPRIT projects, which contributed to the development...

  5. Numerical analysis of stone columns in mitigating liquefaction effects in embankment fills

    Energy Technology Data Exchange (ETDEWEB)

    Borghei, Z.; Soroush, A. [Amirkabir University of Technology, Tehran, (Iran, Islamic Republic of); Noorzad, A. [Power and Water University of Technology, Tehran, (Iran, Islamic Republic of)

    2010-07-01

    The traditional approach to liquefaction in embankment fills is to use in-situ densification. The use of stone columns offers the possibility of preventing liquefaction and associated settlements while reducing the cost and time required for treatment. This paper investigated the behaviour of stone columns using a numerical method. The study focused on a case study, a sand layer beneath two wall tanks, butane and propane NGL, located on Siri Island, Persian Gulf, Iran. Numerical analyses were carried out to evaluate the rate of excess pore pressure build-up in the improved ground. The numerical model results were compared to the simulation results from a centrifuge test for a uniform 19m-thick liquefiable sand layer. The numerical methodology was verified. The results showed that the stone columns can significantly increase the rate of pore pressure dissipation and reduce the settlement. It was found that the installation process densifies the surrounding soil, decreasing the liquefaction potential.

  6. Transcystic duct treatment of common bile duct stones

    International Nuclear Information System (INIS)

    Amberg, J.R.; Chun, G.

    1981-01-01

    Successful removal of 2 retained common bile duct stones following cholecystostomy is described. With the use of the steerable catheter and the wire basket, one stone was crushed and the second was extracted in retrograde fashion through the cystic duct and gallbladder. (orig.)

  7. Ultrasonographic diagnosis of ureteral stones: Accuracy and factors influencing on diagnostic sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Park, Young Mi; Han, Sang Seok; Chang, Seung Kuk; Joo, Sang Hoo; Lee, Jeong Sik; Eun, Choong Ki [Pusan Paik Hospital, Inje University College of Medicine, Pusan (Korea, Republic of)

    1999-12-15

    To determine the accuracy of ultrasonographic diagnosis in patients with clinically suspected ureteral stones and to evaluate the factors influencing on the diagnostic sensitivity for the detection of ureteral stone. The patients (115 cases) with proven presence or absence of ureteral stones were included in the study. At first, both sided kidney and proximal ureters were examined on each decubitus position and then middle ureters were done if proximal ureters were visualized. On the supine view, distal ureters and UVJ were scanned through the acoustic window of the filled bladder. KUB (20 cases), IVU (62 cases), AGP (7 cases), RGP (3 cases), ESWL (9 cases), CT (9 cases), and patients' history of spontaneous passage of stones (5 cases) were included as confirmation methods. The sensitivity, specificity, and accuracy of the ultrasonographic diagnosis of ureteral stones were calculated and the factors influencing on the sensitivity on the focus of the position and size of ureteral stone, visibility of ureter, the presence or absence of renal stone and hydronephrosis were analyzed. Of 82 cases with proven ureteral stone, 72 cases were revealed on ultrasonography and there was one false positive examination among 33 cases with proven absence of ureteral stone. The overall diagnostic accuracy was 90%. The ultrasonographic detection rates of ureteral stones as correlated with their locations were 83% (24/29), 100% (11/11), 80% (16/20), and 100% (21/21) of each group of proximal, middle, distal ureter, and UVJ stones. Of 61 stones, those as correlated with their sizes, were 82% (37/45) and 94% (15/16) of each group less than 10 mm and more than 11 mm. Those as correlated with the presence or absence of ureteral visualization on ultrasonography were 92% (69/75) and 43% (3/7) of each group. Those as correlated with presence of absence of renal stones were 85% (41/48) and 91% (31/34) of each group. Those as correlated with presence or absence of hydronephrosis were 89

  8. Strength Improvement of Clay Soil by Using Stone Powder

    OpenAIRE

    Ahmed Sameer Abdulrasool

    2015-01-01

    Soil stabilization with stone powder is a good solution for the construction of subgrade for road way and railway lines, especially under the platforms and mostly in transition zones between embankments and rigid structures, where the mechanical properties of supporting soils are very influential. Stone powder often has a unique composition which justifies the need for research to study the feasibility of using this stone powder type for ground improvement applications. This paper presents re...

  9. Enriching step-based product information models to support product life-cycle activities

    Science.gov (United States)

    Sarigecili, Mehmet Ilteris

    The representation and management of product information in its life-cycle requires standardized data exchange protocols. Standard for Exchange of Product Model Data (STEP) is such a standard that has been used widely by the industries. Even though STEP-based product models are well defined and syntactically correct, populating product data according to these models is not easy because they are too big and disorganized. Data exchange specifications (DEXs) and templates provide re-organized information models required in data exchange of specific activities for various businesses. DEXs show us it would be possible to organize STEP-based product models in order to support different engineering activities at various stages of product life-cycle. In this study, STEP-based models are enriched and organized to support two engineering activities: materials information declaration and tolerance analysis. Due to new environmental regulations, the substance and materials information in products have to be screened closely by manufacturing industries. This requires a fast, unambiguous and complete product information exchange between the members of a supply chain. Tolerance analysis activity, on the other hand, is used to verify the functional requirements of an assembly considering the worst case (i.e., maximum and minimum) conditions for the part/assembly dimensions. Another issue with STEP-based product models is that the semantics of product data are represented implicitly. Hence, it is difficult to interpret the semantics of data for different product life-cycle phases for various application domains. OntoSTEP, developed at NIST, provides semantically enriched product models in OWL. In this thesis, we would like to present how to interpret the GD & T specifications in STEP for tolerance analysis by utilizing OntoSTEP.

  10. Management of bladder stones: the move towards non-invasive treatment

    Directory of Open Access Journals (Sweden)

    Isaac A. Deswanto

    2017-08-01

    Full Text Available Background: Bladder stone accounts for 5% of all cases of urolithiasis. Bladder stones management has evolved over the last decades from open bladder surgery (sectio alta to intracorporeal cystholithotripsy as well as extracorporeal shock wave lithotripsy (ESWL. ESWL presents to be a promising modality in the management of bladder calculi due to its simplicity and well tolerability. This study is thus conducted to present data on the safety and effectiveness of ESWL in the management of bladder stone patients.Methods: This is a retrospective study evaluating the medical records of 92 bladder calculi patients admitted to Cipto Mangunkusumo General Hospital (RSCM from January 2011 to April 2015. Patient’s age, gender, type of stone and procedure being done, status of stone disintegration, length of hospital stay, and any complications that may occur are noted down and statistically analyzed using SPSS v. 20.Results: Majority of the patients underwent ESWL (49 out of 92, 53.3%. The stone free rates for ESWL, intracorporeal lithotripsy, and sectio alta are 93.9%, 97.0% and 100% respectively. One patient had to repeat ESWL. The ESWL group had the smallest stone size average compared to the intracorporeal lithotripsy and section alta group (2.5 cm±2.0 cm vs 4.8 cm±3.7 cm vs 7.4 cm±5.4 cm respectively. The ESWL sessions were conducted in the outpatient clinic, and thus no hospital stay was required.Conclusion: ESWL can be suggested as an effective non-invasive approach in the disintegration of bladder stone of ≤25 mm with a promisingly high stone-free rate (93.9% Furthermore, ESWL can be performed on an outpatient basis with minimal complications.

  11. A radiologic study of salivary stones

    International Nuclear Information System (INIS)

    Cho, Hyo Suck; Ahn, Hyung Kyu

    1986-01-01

    The author examined fifty cases of sialolithiasis diagnosed in the Dept. of Oral Radiology in SNUH by conventional radiography and sialography, and patient's age, sex, location, radiodensity, numbers, shapes, and relation with ducts a nd parenchymas. The results of this study were as follows: 1. The average age of patients was 38.6 years in submandibular sialolithiasis, and 39.2 years in parotid sialolithiasis. 2. There was slightly higher incidence in males (58.0%) than in females (42.0%). 3. Salivary stones were found to be much more in the submandibular gland and duct (82.0%) than in the parotid gland and duct (18.0%). 4. Of 62 submandibular salivary stones, 33 (53.2%) occurred in the main duct, 25 (40.3%) occurred in the hilum, and 4 (6.5%) occurred in the parenchyma. Of 18 parotid salivary stones, 9(50.0%) occurred in the main duct, 5(27.8%) occurred in the parenchyma, and 4 (22 .2%) occurred in the hilum. 5. Of the submandibular salivary stones, the number of radiopaque type was 45 (75.8%), and the number of radiolucent type was 17 (24.2%). Of the parotid salivary stones, the number of radiopaque type was 12 (66.7%), and the number of radiolucent type was 6 (33.3%). 6. The single type was 30 cases (73.2%) in submandibular gland, 6 cases (66.7%) in parotid gland, and the multiple type was 11 cases (26.8%) in submandibular grand, and 3 cases (33. 3%) in parotid gland. 7. Round shape was 35 cases (43.8%), ovoid shape was 22 cases (27.5%), irregular shape was 17 cases (21.3%), and cylindrical shape was 6 cases (7.5%).

  12. Anatomical factors predicting lower calyceal stone clearance after extracorporeal shockwave lithotripsy

    Directory of Open Access Journals (Sweden)

    M. Khan

    2016-06-01

    Conclusions: This study shows that lower infundibular length and width are significant anatomical factors in determining stone clearance following ESWL treatment of lower calyceal stones and these should be assessed before planning the treatment for lower calyceal stones.

  13. Detection of endolithic spatial distribution in marble stone.

    Science.gov (United States)

    Casanova Municchia, A; Percario, Z; Caneva, G

    2014-10-01

    The penetration of endolithic microorganisms, which develop to depths of several millimetres or even centimetres into the stone, and the diffusion of their extracellular substances speeds up the stone deterioration process. The aim of this study was to investigate, using a confocal laser scanning microscopy with a double-staining, a marble rock sample by observing the endolithic spatial distribution and quantifying the volume they occupied within the stone, in order to understand the real impact of these microorganisms on the conservation of stone monuments. Often the only factors taken into account by biodeterioration studies regarding endolithic microorganisms, are spread and depth of penetration. Despite the knowledge of three-dimensional spatial distribution and quantification of volume, it is indispensable to understand the real damage caused by endolithic microorganisms to stone monuments. In this work, we analyze a marble rock sample using a confocal laser scanning microscopy stained with propidium iodide and Concavalin-A conjugate with the fluorophore Alexa Fluor 488, comparing these results with other techniques (SEM microscope, microphotographs of polished cross-sections and thin-section, PAS staining methods), An image analysis approach has also been applied. The use of confocal laser scanning microscopy with double staining shows clear evidence of the presence of endolithic microorganisms (cyanobacteria and fungi) as well as the extracellular polymeric substance matrix in a three-dimensional architecture as part of the rock sample, this technique, therefore, seems very useful when applied to restoration interventions on stone monuments when endolithic growth is suspected. © 2014 The Authors Journal of Microscopy © 2014 Royal Microscopical Society.

  14. Absolute Hounsfield unit measurement on noncontrast computed tomography cannot accurately predict struvite stone composition.

    Science.gov (United States)

    Marchini, Giovanni Scala; Gebreselassie, Surafel; Liu, Xiaobo; Pynadath, Cindy; Snyder, Grace; Monga, Manoj

    2013-02-01

    The purpose of our study was to determine, in vivo, whether single-energy noncontrast computed tomography (NCCT) can accurately predict the presence/percentage of struvite stone composition. We retrospectively searched for all patients with struvite components on stone composition analysis between January 2008 and March 2012. Inclusion criteria were NCCT prior to stone analysis and stone size ≥4 mm. A single urologist, blinded to stone composition, reviewed all NCCT to acquire stone location, dimensions, and Hounsfield unit (HU). HU density (HUD) was calculated by dividing mean HU by the stone's largest transverse diameter. Stone analysis was performed via Fourier transform infrared spectrometry. Independent sample Student's t-test and analysis of variance (ANOVA) were used to compare HU/HUD among groups. Spearman's correlation test was used to determine the correlation between HU and stone size and also HU/HUD to % of each component within the stone. Significance was considered if pR=0.017; p=0.912) and negative with HUD (R=-0.20; p=0.898). Overall, 3 (6.8%) had stones (n=5) with other miscellaneous stones (n=39), no difference was found for HU (p=0.09) but HUD was significantly lower for pure stones (27.9±23.6 v 72.5±55.9, respectively; p=0.006). Again, significant overlaps were seen. Pure struvite stones have significantly lower HUD than mixed struvite stones, but overlap exists. A low HUD may increase the suspicion for a pure struvite calculus.

  15. Childhood bladder stones-an endemic disease of developing countries

    International Nuclear Information System (INIS)

    Lal, B.

    2015-01-01

    Bladder calculi are one of the commonest health problems in young children especially in rural and underprivileged areas. Methods: All children of bladder stones operated at District Headquarter Hospital Mithi from July 2009 to June 2012 were included in this cross-sectional study. Data was collected regarding age, sex, address (rural or urban), body weight, duration of breast feeding, weaning, detailed dietary history regarding milk type, volume, amount of water intake, recurrent diarrhoea, urinary tract infection (UTI), family history, and socioeconomic history. Urine analysis, complete blood count (CBC), renal function, ultra sound abdomen, X-ray kidney, ureter, and bladder (KUB) was done in all patients. All patients had cystolithotomy and were followed up till complete recovery. Results: A total of 113 children (97 males and 16 females) operated at District Headquarter Hospital Mithi Tharparker were included in study. All patients belonged to local desert areas of Tharparker. Age ranged from 18 months to 14 year (mean age 8.6 year). Most frequent symptom was difficulty in micturition in 76 (67.25%) patients, urinary retention in 18 (15.9%) and stone with pyuria and fever in 12 (10.6%) patients. Recurrent episodes of diarrhoea (more than 3 episodes per year) in 73(65%) patients, recurrent UTI in 51 (45.6%), family history of stone disease in 6 (5%) and associated rectal prolapse in 3(2.6%) patients. On x-ray KUB 111 (98%) patients had single stone in bladder, 2 (2%) had multiple stones and an associated renal and ureteric stone in 5 (4.5%). Mild anaemia (Hb 7-10 gm%) was seen in 35 (39.55%) patients, moderate anaemia (Hb 5-7 gm %) was seen in 21(24%) and severe anaemia (Hb less than 5 gm%) was seen in 14 (16%) patients. All patients had open cystolithotomy for removal of stones under general anaesthesia. Conclusion: Bladder stones are public health problem. Majority of affected patients were less than 5 years old. Low protein diet, dehydration, use of goat milk

  16. Influence of carbonate micro-fabrics on the failure strength of Callovo-Oxfordian clay stones and Opalinus Clay

    International Nuclear Information System (INIS)

    Klinkenberg, M.; Dohrmann, R.; Kaufhold, S.; Siegesmund, S.

    2010-01-01

    Document available in extended abstract form only. The potential use of clay stones as host rock for radioactive waste disposal is currently investigated. For this application, hydraulic conductivity, swelling properties, water uptake, rheological and mechanical properties are of great importance. The Opalinus Clay (Mont-Terri, Switzerland) and the Callovo- Oxfordian clay stone (France) are the most frequently studied clay stones. One goal is to develop a numerical model being able to predict the mechanical behaviour of clay stones under repository-like conditions. Experimental investigations reveal that Opalinus Clay and Callovo-Oxfordian clay stone behave different with respect to the dependence of mechanical strength on the carbonate content. The failure strength of Opalinus Clay decreases with increasing carbonate content, whereas it increases with increasing carbonate content when Callovo-Oxfordian clay stone is considered. To supply proper data and enable reliable model assumptions, the use of suitable experimental techniques for the description of the microstructure is indispensable. After mechanical testing, samples were taken perpendicular to the bedding and polished sections were prepared. The micro-fabrics were investigated using scanning electron microscopy (SEM) and image analysis. Backscattered electron (BSE) images were used for the image analysis because carbonates can be extracted by grey level analysis. The image analysis of the extracted particles provides the following parameters: area, longest and shortest axis of an ellipse (surrounding the particle), perimeter, the angle to horizontal (longest axis), and the aspect ratio (longest axis/shortest axis). Callovo-Oxfordian clay stone shows a homogenous distribution of fine-grained carbonates and dovetail connection of calcium carbonate with the clayey matrix. In contrast Opalinus Clay shows large elongated carbonate grains (high aspect ratios) of shell fragments. Cracks are mostly related to these

  17. Patients' selection for treatment of caliceal diverticular stones with extracorporeal shock wave lithotripsy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Won Hong; Lee, Hee Jeong; Son, Soon Yong; Kang, Seong Ho; Cho, Cheong Chan; Ryu, Meung Sun [AMC, Seoul (Korea, Republic of); Kim, Seung Kook [Kwang-Ju Health College, Kwang-Ju (Korea, Republic of)

    2001-06-01

    Symptoms of caliceal diverticular stones are commonly associated with pain, recurrent urinary tract infection and hematuria. The aim of this study is to select the proper patient for the application of more successful extracorporeal shock wave lithotripsy(ESWL) as a treatment of caliceal diverticular stone. 16 patients with caliceal diverticular stones were treated with ESWL, and all patients had single caliceal diverticulum. The diagnosis of caliceal diverticulum with stones was made by intraveneous pyelography to all patients. On these intravenous pyelogram, we also classified diverticular type, whether the diverticular neck is connected with urinary tract patently, diverticular site and stone number and size. All patients were followed after ESWL by plain film of the kidneys, ureters and bladder and interviewed. Of all patients 44% was shown stone-free completely, also 83% was rendered symptom-free. All patients whose diverticular neck connected with urinary tract patently on the intraveneous pyelogram became stone-free. Of solitary stone 60% and multiple stones (more than 2) 17% became symptom-free. The patients with infection before ESWL 75% had residual stones, of these patients 33% had slightly flank pain, and 25% of patients with stones recurred become stone-free. We propose that more successful ESWL for patients with caliceal diverticular stones select satisfactory patients including that the diverticular neck is connected with urinary tract patently, solitary stone and no infection simultaneously.

  18. [Solitary stones of the lower renal calyx: how to treat?

    Science.gov (United States)

    Martov, A G; Ergakov, D V; Andronov, A S; Dutov, S V; Takhaev, R A; Kil'chukov, Z I; Moskalenko, S A

    2017-06-01

    The choice of treatment for the stones of the lower renal calyx is one of the challenging issues of modern urology. The aim of this retrospective and prospective study was to investigate the clinical effectiveness and safety of 3 modern minimally invasive techniques for treating renal stones: percutaneous (PNL) and transurethral (TNL) nephrolithotripsy and extracorporeal shock wave lithotripsy (ESWL) in patients with solitary lower calyx stones sized from 10 to 15 mm. The study included 136 patients with symptomatic stones of the lower calyces, who underwent ESWL, PNL and TNL from November 2010 to the present day. The criteria for inclusion in the study were: the presence of a solitary stone of the lower calyx, the stone size of 10 mm to 15 mm, the performance of the classical (standard) PNL in the prone position (puncture access 28-30 Fr) and the follow-up examination at 3 months after the operation. Forty-six patients underwent ESWL, 49 - PNL, and 41 - TNL. Postoperative follow-up was done at 3 months and included a plain radiography, ultrasound and non-contrast-enhanced computed tomography. The stone free rate (SFR) was used as a criterion for the effectiveness of the intervention, where the stone size of 3 mm was taken as the upper limit for the possible presence of fragments. Besides, the rate of repeat interventions, complications and subjective assessment of patients treatment satisfaction (0 to 10) by using visual analogue scale (VAS) were investigated. The effectiveness analysis of the three methods for treating the lower calyx stones sized 10-15 mm showed that PNL was no more effective than TNL (SFR 95.9% and 85.4%, respectively), but both methods were significantly more effective than ESWL (SFR 69.5%). 29.3% of patients who underwent TNL required repeat interventions (TNL or ESWL), while among those treated with ESWL, 45.6% required repeat ESWL sessions. PNL resulted in stone clearance in one stage. Postoperative inflammatory complications were most

  19. Safety and efficacy of staged retrograde intrarenal surgery for large stone burden of renal stones in selected patients: A single-center experience

    Directory of Open Access Journals (Sweden)

    Cheng-Feng Lin

    2017-06-01

    Conclusion: To the best of our knowledge, RIRS for large renal stone manipulation is an effective and safe treatment modality currently. In our study, the single RIRS SFR was superior to PNL or SWL even when the stone burden was between 2.0 cm and 3.0 cm (80.2%. For those patients whose stone burden was over 3.0 cm or for those with comorbidities, staged RIRS resulted in a lower complication rate, reduced hospital stay, and better SFR (76.5%.

  20. Investigations of excavated clay-stone as backfill/seal material

    International Nuclear Information System (INIS)

    Zhang, Chun-Liang

    2012-01-01

    Document available in extended abstract form only. Crushed clay-stone produced by excavation activities of repository drifts has been investigated as backfill/seal material at the GRS laboratory. The raw aggregate with coarse grains is considered to be used for backfilling the repository openings and, in mixture with bentonite, for sealing the boreholes, drifts and shafts. The GRS research programme focused on characterizing the thermo-hydro-mechanical properties of the excavated Callovo-Oxfordian clay-stone (COX) and the clay-stone-bentonite mixtures, including mechanical compaction, gas and water permeability as function of porosity, water retention and saturation, swelling capacity, and thermal properties of the materials. The most important results are presented in this paper. Figure 1 shows the compaction and permeability behaviour of the excavated clay-stone with grains up to a size of 32 mm. The results were obtained on large samples of 280 mm diameter and 680 mm height under quasi-hydrostatic compression. The porosity and permeability decrease with increasing load. The porosity-mean stress relation is non-linear and may be expressed by an exponential function. The backfill becomes stiffer at low porosities and can sustain certain deviatoric loads. At porosity of ∼21 %, the strength is characterized by an inherent cohesion of 3.7 MPa and an internal friction angle of 12 deg.. Additionally, the compaction is also dependent on time or loading rate, water content, and temperature. The compaction of the porous backfill material leads to a reduction in permeability. The measured gas permeability decreases much faster at low porosities below ∼25 %. The gas permeability at porosity of ∼20 % becomes as low as that of 10 -20 - 10 -21 m 2 for the intact clay rock. This is probably due to disconnection of the pore network during the compaction. As sealing material, powdered COX clay-stone was mixed with MX80 bentonite powder in different ratios and compacted to

  1. Mini vs standard percutaneous nephrolithotomy for renal stones: a comparative study.

    Science.gov (United States)

    ElSheemy, Mohammed S; Elmarakbi, Akram A; Hytham, Mohammed; Ibrahim, Hamdy; Khadgi, Sanjay; Al-Kandari, Ahmed M

    2018-03-16

    To compare the outcome of mini-percutaneous nephrolithotomy (Mini-PNL) versus standard-PNL for renal stones. Retrospective study was performed between March 2010 and May 2013 for patients treated by Mini-PNL or standard-PNL through 18 and 30 Fr tracts, respectively, using pneumatic lithotripsy. Semirigid ureteroscope (8.5/11.5 Fr) was used for Mini-PNL and 24 Fr nephroscope for standard-PNL. Both groups were compared in stone free rate(SFR), complications and operative time using Student-t, Mann-Whitney, Chi square or Fisher's exact tests as appropriate in addition to logistic regression analysis. P PNL (378) and standard-PNL (151) were nearly comparable in patients and stones criteria including stone burden (3.77 ± 2.21 vs 3.77 ± 2.43 cm 2 ; respectively). There was no significant difference in number of tracts or supracostal puncture. Mini-PNL had longer operative time (68.6 ± 29.09 vs 60.49 ± 11.38 min; p = 0.434), significantly shorter hospital stay (2.43 ± 1.46 vs 4.29 ± 1.28 days) and significantly higher rate of tubeless PNL (75.1 vs 4.6%). Complications were significantly higher in standard-PNL (7.9 vs 20.5%; p PNL (89.9 vs 96%; p = 0.022). This significant difference was found with multiple stones and large stone burden (> 2 cm 2 ), but the SFR was comparable between both groups with single stone or stone burden ≤ 2 cm. Logistic regression analysis confirmed significantly higher complications and SFR with standard-PNL but with significantly shorter operative time. Mini-PNL has significantly lower SFR when compared to standard-PNL (but clinically comparable) with markedly reduced complications and hospital stay. Most of cases can be performed tubeless. The significant difference in SFR was found with multiple stones or large stone burden (> 2 cm 2 ), but not with single stones or stone burden ≤ 2 cm 2 .

  2. Bariatric Surgery and Urinary Stone Disease

    Directory of Open Access Journals (Sweden)

    Cevahir Ozer

    2016-07-01

    Full Text Available Obesity is a major public health problem and has been suggested to play a role in the etiology of urinary tract stone disease. Furthermore, the increasingly widespread use of surgery in the treatment of obesity also is related with urinary stone disease. In daily practice, patients to whom obesity surgery has been planned or who have undergone obesity surgery are seen more frequently. This review aims to highlight the urological evaluation and management of this patient group.

  3. Utility of Flexible Ureterorenoscopy and Laser Lithotripsy in the Treatment of Multiple Intrarenal Stones

    Directory of Open Access Journals (Sweden)

    Hasan Yılmaz

    2017-09-01

    Full Text Available Objective: We aimed to determine the safety and efficacy of flexible ureterorenoscopy and Holmium laser lithotripsy in treating multiple intrarenal stones. Materials and Methods: We identified 32 consecutive patients with multiple intrarenal stones who underwent flexible ureterorenoscopy and/or laser lithotripsy performed by a single surgeon. Informed consent was obtained from all participants before treatment. Each patient was evaluated in terms of stone location, stone number, stone size, stone burden (cumulative stone length, body mass index, operative time, stone-free rate, and perioperative complications. Results: The median age of the patients was 38 years [interquartile range (IQR, 34.25-52.00]. The patients had a total of 75 intrarenal calculi. The average number of stones per patient was 2.50 (IQR, 2.0-3.0. The median total stone burden per patient was 23.0 mm (IQR, 19.0-28.0 mm. Twenty-one patients (65.5% had stone burdens >20 mm, and 11 (34.5% had burdens ≤20 mm. The overall final stone-free rate was 78.1%. The stone-free rates for patients with stone burdens ≤20 mm and >20 mm were 81.8% (9/11 and 76.2% (16/21, respectively (p=0.544. A perioperative complication (urinary leakage occurred in one patient. Postoperative complications were recorded in four (12.5% patients; a urinary tract infection in one, pain requiring parenteral medication in two, and hematuria in one. Conclusion: Flexible ureterorenoscopy combined with laser lithotripsy may be an effective treatment option for patients with multiple intrarenal stones; we noted only a few minor complications. The success rate was higher in patients with stone burdens ≤20 mm.

  4. Frequency and factors effecting non clearance of lower pole renal stones

    International Nuclear Information System (INIS)

    Ullah, A.; Zubair, M.; Khan, N.; Malik, A.

    2015-01-01

    Renal stone disease is a major health hazard in Pakistan and extra-corporeal shockwave lithotripsy is one of comprehensive method used to treat these stones. The aim of this study is to determine the frequency of factors affecting the non-clearance of stone fragments of lower pole renal stone after extra corporeal shockwave lithotripsy. The study was done with the objective to determine the frequency the spatial anatomical factors which can influence the non-clearance of lower pole stone fragments after ESWL. Methods: One and nineteen (119) patients with lower pole renal stone less than 10 mm were subjected to maximum 3 sessions of extracorporeal shock wave lithotripsy. KUB radiographs, ultrasonography and intravenous urography were used as investigative tools for lower pole renal calyceal anatomy. X ray KUB and ultrasound were done after a week for clearance. Data was analysed with the help of SPSS version 10.0 and presented in the forms of tables and graphs. Results: There were 77 (64.71%) males and 42 (35.29%) females. Infundibulo-pelvic angle (IPA)>40 degree was present in 93 (78.15%), Infundibular length (IL) <22 mm in 107 (89.92%) and Infundibular width (IW) >4 mm was present in 100 (84.03%) patients. The frequency of stone non clearance was noted in 31 (26.05%). Infundibulo-pelvic angle (IPA)>40 degree (p=0.000), Infundibular length (IL)<22 mm (p=0.001) and Infundibular width (IW)>4 mm (p=0.046) were significant variables affecting stone clearance. Conclusion: The frequency of non-clearance of lower calyx of kidney stone is 26.05%. The clearance of fragments of the lower calyx kidney stones is affected by three spatial anatomical factors, i.e., Infundibulopelvic angle, Infundibular width and infundibular length. (author)

  5. Automated visual inspection for polished stone manufacture

    Science.gov (United States)

    Smith, Melvyn L.; Smith, Lyndon N.

    2003-05-01

    Increased globalisation of the ornamental stone market has lead to increased competition and more rigorous product quality requirements. As such, there are strong motivators to introduce new, more effective, inspection technologies that will help enable stone processors to reduce costs, improve quality and improve productivity. Natural stone surfaces may contain a mixture of complex two-dimensional (2D) patterns and three-dimensional (3D) features. The challenge in terms of automated inspection is to develop systems able to reliably identify 3D topographic defects, either naturally occurring or resulting from polishing, in the presence of concomitant complex 2D stochastic colour patterns. The resulting real-time analysis of the defects may be used in adaptive process control, in order to avoid the wasteful production of defective product. An innovative approach, using structured light and based upon an adaptation of the photometric stereo method, has been pioneered and developed at UWE to isolate and characterize mixed 2D and 3D surface features. The method is able to undertake tasks considered beyond the capabilities of existing surface inspection techniques. The approach has been successfully applied to real stone samples, and a selection of experimental results is presented.

  6. Percutaneous Transhepatic Removal of Bile Duct Stones: Results of 261 Patients

    Energy Technology Data Exchange (ETDEWEB)

    Ozcan, Nevzat, E-mail: nevzatcan@yahoo.com; Kahriman, Guven, E-mail: guvenkahriman@hotmail.com; Mavili, Ertugrul, E-mail: ertmavili@yahoo.com [Erciyes University, Department of Radiology, Medical Faculty (Turkey)

    2012-08-15

    Purpose: To determine the effectiveness of percutaneous transhepatic removal of bile duct stones when the procedure of endoscopic therapy fails for reasons of anatomical anomalies or is rejected by the patient. Methods: Between April 2001 and May 2010, 261 patients (138 male patients and 123 female patients; age range, 14-92 years; mean age, 64.6 years) with bile duct stones (common bile duct [CBD] stones = 248 patients and hepatolithiasis = 13 patients) were included in the study. Percutaneous transhepatic cholangiography was performed, and stones were identified. Percutaneous transhepatic balloon dilation of the papilla of Vater was performed. Then stones were pushed out into the duodenum with a Fogarty balloon catheter. If the stone diameter was larger than 15 mm, then basket lithotripsy was performed before balloon dilation. Results: Overall success rate was 95.7%. The procedure was successful in 97.5% of patients with CBD stones and in 61.5% of patients with hepatolithiasis. A total of 18 major complications (6.8%), including cholangitis (n = 7), subcapsular biloma (n = 4), subcapsular hematoma (n = 1), subcapsular abscess (n = 1), bile peritonitis (n = 1), duodenal perforation (n = 1), CBD perforation (n = 1), gastroduodenal artery pseudoaneurysm (n = 1), and right hepatic artery transection (n = 1), were observed after the procedure. There was no mortality. Conclusion: Our experience suggests that percutaneous transhepatic stone expulsion into the duodenum through the papilla is an effective and safe approach in the nonoperative management of the bile duct stones. It is a feasible alternative to surgery when endoscopic extraction fails or is rejected by the patient.

  7. Percutaneous Transhepatic Removal of Bile Duct Stones: Results of 261 Patients

    International Nuclear Information System (INIS)

    Ozcan, Nevzat; Kahriman, Guven; Mavili, Ertugrul

    2012-01-01

    Purpose: To determine the effectiveness of percutaneous transhepatic removal of bile duct stones when the procedure of endoscopic therapy fails for reasons of anatomical anomalies or is rejected by the patient. Methods: Between April 2001 and May 2010, 261 patients (138 male patients and 123 female patients; age range, 14–92 years; mean age, 64.6 years) with bile duct stones (common bile duct [CBD] stones = 248 patients and hepatolithiasis = 13 patients) were included in the study. Percutaneous transhepatic cholangiography was performed, and stones were identified. Percutaneous transhepatic balloon dilation of the papilla of Vater was performed. Then stones were pushed out into the duodenum with a Fogarty balloon catheter. If the stone diameter was larger than 15 mm, then basket lithotripsy was performed before balloon dilation. Results: Overall success rate was 95.7%. The procedure was successful in 97.5% of patients with CBD stones and in 61.5% of patients with hepatolithiasis. A total of 18 major complications (6.8%), including cholangitis (n = 7), subcapsular biloma (n = 4), subcapsular hematoma (n = 1), subcapsular abscess (n = 1), bile peritonitis (n = 1), duodenal perforation (n = 1), CBD perforation (n = 1), gastroduodenal artery pseudoaneurysm (n = 1), and right hepatic artery transection (n = 1), were observed after the procedure. There was no mortality. Conclusion: Our experience suggests that percutaneous transhepatic stone expulsion into the duodenum through the papilla is an effective and safe approach in the nonoperative management of the bile duct stones. It is a feasible alternative to surgery when endoscopic extraction fails or is rejected by the patient.

  8. Characterization and analysis of CCR and CAD gene families at the whole-genome level for lignin synthesis of stone cells in pear (Pyrus bretschneideri fruit

    Directory of Open Access Journals (Sweden)

    Xi Cheng

    2017-11-01

    Full Text Available The content of stone cells has significant effects on the flavour and quality of pear fruit. Previous research suggested that lignin deposition is closely related to stone cell formation. In the lignin biosynthetic pathway, cinnamoyl-CoA reductase (CCR and cinnamyl alcohol dehydrogenase (CAD, dehydrogenase/reductase family members, catalyse the last two steps in monolignol synthesis. However, there is little knowledge of the characteristics of the CCR and CAD families in pear and their involvement in lignin synthesis of stone cells. In this study, 31 CCRs and 26 CADs were identified in the pear genome. Phylogenetic trees for CCRs and CADs were constructed; key amino acid residues were analysed, and three-dimensional structures were predicted. Using quantitative real-time polymerase chain reaction (qRT-PCR, PbCAD2, PbCCR1, -2 and -3 were identified as participating in lignin synthesis of stone cells in pear fruit. Subcellular localization analysis showed that the expressed proteins (PbCAD2, PbCCR1, -2 and -3 are found in the cytoplasm or at the cell membrane. These results reveal the evolutionary features of the CCR and CAD families in pear as well as the genes responsible for regulation of lignin synthesis and stone cell development in pear fruit.

  9. The fragmented character of Middle Palaeolithic stone tool technology.

    Science.gov (United States)

    Turq, Alain; Roebroeks, Wil; Bourguignon, Laurence; Faivre, Jean-Philippe

    2013-11-01

    The importance of the transport of stone artefacts in structuring Neandertal lithic assemblages has often been addressed, but the degree to which this led to fragmentation of lithic reduction over Middle Palaeolithic landscapes has not been explicitly studied thus far. Large-scale excavations of Middle Palaeolithic open-air sites and refitting studies of the retrieved assemblages have yielded new, high-resolution data on the mobile aspects of Neandertal stone tool technology. In this paper, we integrate lithic technology and raw material data from recent studies of Middle Palaeolithic open-air and rock shelter sites in Western Europe. We demonstrate that the results of a variety of typological, technological (especially refitting), and lithological studies have important consequences for our knowledge of the acquisition of raw materials and subsequent production, usage and discard of stone artefacts in the Middle Palaeolithic. Neandertal production and use of stone tools was fragmented in three domains: the spatial, the temporal and the social domain. We show that this versatile segmentation of stone artefact handling strategies is a main determinant of the character of the Neandertal archaeological record. Our data testify to ubiquitous and continuous transport of stone artefacts of a wide variety of forms, picked by Neandertals using selection criteria that were sometimes far removed from what archaeologists have traditionally considered, and to some degree still consider, to be desired end products of knapping activities. The data presented here testify to the variability and versatility of Middle Palaeolithic stone tool technology, whose fragmented character created very heterogeneous archaeological assemblages, usually the product of a wide variety of independent import, use, discard and/or subsequent transport events. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. STEPS: efficient simulation of stochastic reaction–diffusion models in realistic morphologies

    Directory of Open Access Journals (Sweden)

    Hepburn Iain

    2012-05-01

    Full Text Available Abstract Background Models of cellular molecular systems are built from components such as biochemical reactions (including interactions between ligands and membrane-bound proteins, conformational changes and active and passive transport. A discrete, stochastic description of the kinetics is often essential to capture the behavior of the system accurately. Where spatial effects play a prominent role the complex morphology of cells may have to be represented, along with aspects such as chemical localization and diffusion. This high level of detail makes efficiency a particularly important consideration for software that is designed to simulate such systems. Results We describe STEPS, a stochastic reaction–diffusion simulator developed with an emphasis on simulating biochemical signaling pathways accurately and efficiently. STEPS supports all the above-mentioned features, and well-validated support for SBML allows many existing biochemical models to be imported reliably. Complex boundaries can be represented accurately in externally generated 3D tetrahedral meshes imported by STEPS. The powerful Python interface facilitates model construction and simulation control. STEPS implements the composition and rejection method, a variation of the Gillespie SSA, supporting diffusion between tetrahedral elements within an efficient search and update engine. Additional support for well-mixed conditions and for deterministic model solution is implemented. Solver accuracy is confirmed with an original and extensive validation set consisting of isolated reaction, diffusion and reaction–diffusion systems. Accuracy imposes upper and lower limits on tetrahedron sizes, which are described in detail. By comparing to Smoldyn, we show how the voxel-based approach in STEPS is often faster than particle-based methods, with increasing advantage in larger systems, and by comparing to MesoRD we show the efficiency of the STEPS implementation. Conclusion STEPS simulates

  11. Validating automated kidney stone volumetry in computed tomography and mathematical correlation with estimated stone volume based on diameter.

    Science.gov (United States)

    Wilhelm, Konrad; Miernik, Arkadiusz; Hein, Simon; Schlager, Daniel; Adams, Fabian; Benndorf, Matthias; Fritz, Benjamin; Langer, Mathias; Hesse, Albrecht; Schoenthaler, Martin; Neubauer, Jakob

    2018-06-02

    To validate AutoMated UroLithiasis Evaluation Tool (AMULET) software for kidney stone volumetry and compare its performance to standard clinical practice. Maximum diameter and volume of 96 urinary stones were measured as reference standard by three independent urologists. The same stones were positioned in an anthropomorphic phantom and CT scans acquired in standard settings. Three independent radiologists blinded to the reference values took manual measurements of the maximum diameter and automatic measurements of maximum diameter and volume. An "expected volume" was calculated based on manual diameter measurements using the formula: V=4/3 πr³. 96 stones were analyzed in the study. We had initially aimed to assess 100. Nine were replaced during data acquisition due of crumbling and 4 had to be excluded because the automated measurement did not work. Mean reference maximum diameter was 13.3 mm (5.2-32.1 mm). Correlation coefficients among all measured outcomes were compared. The correlation between the manual and automatic diameter measurements to the reference was 0.98 and 0.91, respectively (pvolumetry is possible and significantly more accurate than diameter-based volumetric calculations. To avoid bias in clinical trials, size should be measured as volume. However, automated diameter measurements are not as accurate as manual measurements.

  12. Getter Incorporation into Cast Stone and Solid State Characterizations

    Energy Technology Data Exchange (ETDEWEB)

    Asmussen, Robert M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lawter, Amanda R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stephenson, John R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bowden, Mark E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Washton, Nancy M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Neeway, James J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Du, Yingge [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pearce, Carolyn I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Clayton, Ray E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Saslow, Sarah A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buck, Edgar C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cordova, Elsa [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Qafoku, Nikolla [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-09-28

    Washington River Protection Solutions (WRPS) is collecting relevant available data on waste forms for use as a supplemental immobilization technology, to provide the additional capacity needed to treat low-activity waste (LAW) in Hanford Site tanks and complete the tank waste cleanup mission in a timely and cost-effective manner. One candidate supplemental waste form, fabricated using a low-temperature process, is a cementitious grout called Cast Stone. Cast Stone has been under investigation for this application at Pacific Northwest National Laboratory (PNNL) since initial screening tests in FY13. This report is the culmination of work to lower the diffusivities of Tc and I from Cast Stone using getters. Getters are compounds added to a system designed to selectively sequester a species of interest to provide increased stability to the species. The work contained within this report is related to waste form development and testing, and does not directly support the 2017 integrated disposal facility (IDF) performance assessment. However, this work contains valuable information which may be used in performance assessment maintenance past FY17, and in future waste form development. This report on performance characterization of Tc and I getters in Cast Stone fabricated with simulated LAW covers several areas of interest and major findings to WRPS: investigating performance of potassium metal sulfide (KMS-2-SS) and tin (II) apatite (Sn-A) as Tc getters when incorporated into Cast Stone; investigating performance of silver exchanged zeolite (Ag-Z) and argentite (Arg) as I getters when incorporated into Cast Stone; utilizing sequential addition of Tc and I getters to overcome any deleterious interactions between the getters in solution; determining, for the first time, Tc distribution within the cured Cast Stone and its evolution during leaching; and performing solid state characterization of getters and Cast Stone samples to support leach test findings and develop a

  13. Connectivity among subpopulations of Louisiana black bears as estimated by a step selection function

    Science.gov (United States)

    Clark, Joseph D.; Jared S. Laufenberg,; Maria Davidson,; Jennifer L. Murrow,

    2015-01-01

    cover in private ownership. The addition of hypothetical 1,000-m- or 3,000-m-wide corridors between the 4 study areas had minimal effects on connectivity among subpopulations. For females, our model suggested that habitat between subpopulations would probably have to be permanently occupied for demographic rescue to occur. Thus, the establishment of stepping-stone populations, such as the reintroduced population that we studied, may be a more effective conservation measure than long corridors without a population presence in between. 

  14. Novelda Stone: widely used within the Spanish architectural heritage

    Directory of Open Access Journals (Sweden)

    Fort, R.

    2002-06-01

    Full Text Available Novelda Stone is a calcareous rock, of the biocalcarenite type. It is extracted from the «Vinalopó Medio» area (Alicante, eastern Spain. Novelda stone is known as construction material from the 13th century. From final of the 19th century until the present time, it has been used in Madrid, Valencia and Alicante. In the past, the main quarries from which this type of rock was extracted were located in the municipal districts of Monóvar (Almorquí Stone, Sax (Portazgo Stone and Elda (Bateig Stone. Nowadays, the main active extraction site is situated in the Bateig Hill quarries. The rock extracted is known commercially as Bateig Stone. The main varieties of this Bateig Stone are: White, Blue, Layer and Fantasy. Each variety of Novelda stone has different durability rate and different pathology depending on their characteristics, particularly on their hydric behaviour patterns. Layer Bateig and Portazgo stone undergo granular disintegration and alveolization and are less durable than the rest. White and Blue Bateig, as well as Almorquí stone, only develop fissures or scaling under extreme conditions.

    La Piedra de Novelda es una roca carbonática del tipo biocalcarenita. Se extrae del área de Vinalopó Medio (Alicante, España oriental. La piedra de Novelda es conocida como material de construcción desde el siglo XIII. Desde finales del siglo XIX hasta la actualidad, se ha utilizado en edificios y monumentos de Madrid y Valencia, así como Alicante. En el pasado, las canteras principales donde se extrajo este tipo de piedra se localizaban en los distritos municipales de Monóvar (Piedra Almorquí, Sax (Piedra Portazgo y El da (Piedra Bateig. Hoy en día, la actividad principal se sitúa en las canteras de Bateig. La piedra extraída es conocida comercialmente como Piedra Bateig. Las variedades principales de esta Piedra Bateig son: Blanco, Azul, Llano y Fantasía. Consecuencia de las diferentes propiedades y en especial de los

  15. Sustainable materials used as stone column filler: A short review

    Science.gov (United States)

    Zukri, Azhani; Nazir, Ramli

    2018-04-01

    Stone columns (also known as granular piles) are one of the methods for soft soil stabilization and typically used to increase bearing capacity and stability of slope.; Apart from decreasing the compressibility of loose and fine graded soils, it also accelerates the consolidation effect by improving the drainage path for pore water pressure dissipation and reduces the liquefaction potential of soils during earthquake event. Stone columns are probably the most “natural” ground treatment method or foundation system in existence to date. The benefit of stone columns is owing to the partial replacement of compressible soil by more competent materials such as stone aggregate, sand and other granular materials. These substitutes also act as reinforcement material, hence increasing overall strength and stiffness of the soft soil. Nowadays, a number of research has been conducted on the behaviour and performance of stone columns with various materials utilized as column filler replacing the normal aggregate. This paper will review extensively on previously conducted research on some of the materials used as stone column backfill materials, its suitability and the effectiveness as a substitute for regular aggregates in soft soil improvement works.

  16. Urethral obstruction from dislodged bladder Diverticulum stones: a case report

    Directory of Open Access Journals (Sweden)

    Okeke Linus I

    2012-11-01

    Full Text Available Abstract Background Secondary urethral stone although rare, commonly arises from the kidneys, bladder or are seen in patients with urethral stricture. These stones are either found in the posterior or anterior urethra and do result in acute urinary retention. We report urethral obstruction from dislodged bladder diverticulum stones. This to our knowledge is the first report from Nigeria and in English literature. Case presentation A 69 year old, male, Nigerian with clinical and radiological features of acute urinary retention, benign prostate enlargement and bladder diverticulum. He had a transurethral resection of the prostate (TURP and was lost to follow up. He re-presented with retained urethral catheter of 4months duration. The catheter was removed but attempt at re-passing the catheter failed and a suprapubic cystostomy was performed. Clinical examination and plain radiograph of the penis confirmed anterior and posterior urethral stones. He had meatotomy and antegrade manual stone extraction with no urethra injury. Conclusions Urethral obstruction can result from inadequate treatment of patient with benign prostate enlargement and bladder diverticulum stones. Surgeons in resource limited environment should be conversant with transurethral resection of the prostate and cystolithotripsy or open prostatectomy and diverticulectomy.

  17. Mold attack on frescoes and stone walls of Gradac monastery

    Directory of Open Access Journals (Sweden)

    Stupar Miloš Č.

    2011-01-01

    Full Text Available Microfungi can colonize stone surfaces and form sub-aerial biofilms which can lead to biodeterioration of historic monuments. In this investigation samples for mycological analyses were collected from stone material with visible alteration on stone walls of Gradac monastery exterior. The prevailing fungi found on stone walls were dematiaceous hyphomycetes with melanized hyphae and reproductive structures (Alternaria, Aureobasidium, Cladosporium and Epicoccum species. The frescoes inside the monastery building were also analyzed for the presence of mycobiota. The predominant fungi found on frescoes were osmophilic species from genera Aspergillus and Penicillium. The significant result is identification of human pathogen species Aspergillus fumigatus on frescoes.

  18. Prediction of axial limit capacity of stone columns using dimensional analysis

    Science.gov (United States)

    Nazaruddin A., T.; Mohamed, Zainab; Mohd Azizul, L.; Hafez M., A.

    2017-08-01

    Stone column is the most favorable method used by engineers in designing work for stabilization of soft ground for road embankment, and foundation for liquid structure. Easy installation and cheaper cost are among the factors that make stone column more preferable than other method. Furthermore, stone column also can acts as vertical drain to increase the rate of consolidation during preloading stage before construction work started. According to previous studied there are several parameters that influence the capacity of stone column. Among of them are angle friction of among the stones, arrangement of column (two pattern arrangement most applied triangular and square), spacing center to center between columns, shear strength of soil, and physical size of column (diameter and length). Dimensional analysis method (Buckingham-Pi Theorem) has used to carry out the new formula for prediction of load capacity stone columns. Experimental data from two previous studies was used for analysis of study.

  19. A novel technique of percutaneous stone extraction in choledocholithiasis after cholecystostomy.

    Science.gov (United States)

    Lim, Kyoung Hoon; Kim, Yong Joo

    2013-05-01

    To evaluate the technical feasibility and clinical efficacy of percutaneous common bile duct stone extraction via cystic duct after percutaneous cholecystostomy. Twenty-five consecutive patients with choledocholithiasis underwent percutaneous stone extraction under conscious sedation. The stones were extracted through the 12-Fr sheath using Wittich nitinol stone basket under fluoroscopic guidance via cystic duct after percutaneous trnas-hepatic cholecystostomy. Common bile duct stones were successfully removed in 22 of the 25 patients (88%) by this new technique. The causes of failure in three patients were bile leakage, hematoma of the gallbladder and failure of cystic duct cannulation. Cystic duct injury during this procedure did not occur and there was no post-procedure mortality. The mean period of indwelling catheter was 8.7±4.6 days and the mean duration of hospitalization was 13.4±5.9 days. Percutaneous commmon bile duct stone extraction via the cystic duct through percutaneous cholecystostomy route is effective and feasible for treating choledocholithiasis.

  20. Should flexible ureteroscope be added to our armamentarium to treat stone disease?

    Directory of Open Access Journals (Sweden)

    Anand Dharaskar

    2008-01-01

    Full Text Available The field of Urology in Medicine has witnessed tremendous advancement in technology and in accordance with it. Endourology has taken a leap ahead in terms of stone management. Most of the stones could be treated with semi-rigid ureteroscopy, percutaneous nephrolithotomy (PNL and ESWL and some would need Flexible ureteroscopy. Flexible ureteroscopy has been primarily indicated to treat ESWL resistant renal stones but with changes in the technology of incorporating secondary active deflection and availability of laser fibres, its horizon for indications to treat stones is being widened. Though Flexible ureteroscopy is being used to treat stones of various sizes and locations, its cost effectiveness is debatable. Should it be used ubiquitously to treat stones amenable to PNL or ESWL is a big question we need to answer. As of now true indications of Flexible ureteroscopy are limited and there is an urgent need for a randomized trial to compare its efficacy with ESWL and PNL for renal and upper ureteric stones.

  1. Evidence suggesting a genetic contribution to kidney stone in northeastern Thai population.

    Science.gov (United States)

    Sritippayawan, Suchai; Borvornpadungkitti, Sombat; Paemanee, Atchara; Predanon, Chagkrapan; Susaengrat, Wattanachai; Chuawattana, Duangporn; Sawasdee, Nunghathai; Nakjang, Sirintra; Pongtepaditep, Suttikarn; Nettuwakul, Choochai; Rungroj, Nanyawan; Vasuvattakul, Somkiat; Malasit, Prida; Yenchitsomanus, Pa-thai

    2009-06-01

    Genetic factor may play a role in the pathogenesis of kidney stone that is found in the northeastern (NE) Thai population. Herein, we report initial evidence suggesting genetic contribution to the disease in this population. We examined 1,034 subjects including 135 patients with kidney stone, 551 family members, and 348 villagers by radiography of kidney-ureter-bladder (KUB) and other methods, and also analyzed stones removed by surgical operations. One hundred and sixteen of 551 family members (21.05%) and 23 of the 348 villagers (6.61%) were affected with kidney stone. The relative risk (lambda(R)) of the disease among family members was 3.18. Calcium stones (whewellite, dahllite, and weddellite) were observed in about 88% of stones analyzed. Our data indicate familial aggregation of kidney stone in this population supporting that genetic factor should play some role in its pathogenesis. Genetic and genomic studies will be conducted to identify the genes associated with the disease.

  2. Terahertz lens made out of natural stone.

    Science.gov (United States)

    Han, Daehoon; Lee, Kanghee; Lim, Jongseok; Hong, Sei Sun; Kim, Young Kie; Ahn, Jaewook

    2013-12-20

    Terahertz (THz) time-domain spectroscopy probes the optical properties of naturally occurring solid aggregates of minerals, or stones, in the THz frequency range. Refractive index and extinction coefficient measurement reveals that most natural stones, including mudstone, sandstone, granite, tuff, gneiss, diorite, slate, marble, and dolomite, are fairly transparent for THz frequency waves. Dolomite in particular exhibits a nearly uniform refractive index of 2.7 over the broad frequency range from 0.1 to 1 THz. The high index of refraction allows flexibility in lens designing with a shorter accessible focal length or a thinner lens with a given focal length. Good agreement between the experiment and calculation for the THz beam profile confirms that dolomite has high homogeneity as a lens material, suggesting the possibility of using natural stones for THz optical elements.

  3. Pumice stones as potential in-situ burning enhancer

    DEFF Research Database (Denmark)

    Rojas Alva, U.; Andersen, Bjørn Skjønning; Jomaas, Grunde

    2018-01-01

    Small-scale and mid-scale experiments were conducted in order to evaluate pumice stones as a potential enhancement for in-situ burning (ISB). Four oil types, several emulsification degrees of one crude oil were studied. In general, it was observed that the pumice stones did not improve the burning...... and after the burn, thus bringing the oil into the water column. Finally, the species production of CO and CO2 was not reduced. Based on the presented results, pumice stones have a negative impact on the efficiency of ISB, and they are ruled out as an ISB enhancer and should not be used in relation to ISB....

  4. Process of preparing artificial stone from oil-shale

    Energy Technology Data Exchange (ETDEWEB)

    1921-02-10

    A process for the preparation of artificial stone from oil-shale slag is characterized by the fact that the coarse part of the ground slag before working into artificial stone is saturated with water and serves as filler, while the fine part is milled to dust and forms the binding material.

  5. Laparoscopic surgery for renal stones: is it indicated in the modern endourology era?

    Directory of Open Access Journals (Sweden)

    Andrei Nadu

    2009-02-01

    Full Text Available Purpose: To report the outcomes of laparoscopic surgery combined with endourological assistance for the treatment of renal stones in patients with associated anomalies of the urinary tract. To discuss the role of laparoscopy in kidney stone disease. Materials and Methods: Thirteen patients with renal stones and concomitant urinary anomalies underwent laparoscopic stone surgery combined with ancillary endourological assistance as needed. Their data were analyzed retrospectively including stone burden, associated malformations, perioperative complications and outcomes. Results: Encountered anomalies included ureteropelvic junction obstruction, horseshoe kidney, ectopic pelvic kidney, fussed-crossed ectopic kidney, and double collecting system. Treatment included laparoscopic pyeloplasty, pyelolithotomy, and nephrolithotomy combined with flexible nephroscopy and stone retrieval. Intraoperative complications were lost stones in the abdomen diagnosed in two patients during follow up. Mean number of stones removed was 12 (range 3 to 214. Stone free status was 77% (10/13 and 100% after one ancillary treatment in the remaining patients. One patient had a postoperative urinary leak managed conservatively. Laparoscopic pyeloplasty was successful in all patients according to clinical and dynamic renal scan parameters. Conclusions: In carefully selected patients, laparoscopic and endourological techniques can be successfully combined in a one procedure solution that deals with complex stone disease and repairs underlying urinary anomalies.

  6. Usefulness of 99mTc-DTPA renography and diuretic renography in predicting successful stone discharge following outpatient ESWL in patients with a single ureteral stone

    International Nuclear Information System (INIS)

    Soga, Norihito; Komeda, Yoshinori; Suzuki, Ryuichi; Kawamura, Juichi.

    1996-01-01

    We analyzed the 99m Tc-DTPA renogram with and without diuresis to predict the possibility of stone discharge on the outpatient basis by renogram patterns. Between October 1993 and December 1995, 99m Tc-DTPA renography was performed in 79 patients with a single ureteral stone. The 99m Tc-DTPA renogram pattern was classified into the three types of normal function, obstruction and lower function patterns and the complete stone discharge rate was 93, 63 and 25%, respectively. In addition, diuretic renography using Furosemide was performed in patients with an obstruction pattern and the three renogram patterns of return to the normal curve, a diuretic response and no response were obtained; the complete stone discharge rate was 44, 65.3 and 93%, respectively. From this study, patients with a single ureteral stone with a normal pattern on the regular DTPA renogram and patients with no response pattern on the diuretic renogram, even if in such patients an obstructive pattern was seen on the regular DTPA renogram, seem to be a good candidate for obtaining a high rate of a stone discharge with extracorporeal shock wave lithotripsy (ESWL) treatment in the outpatients basis. (author)

  7. Cholecystectomy for Prevention of Recurrence after Endoscopic Clearance of Bile Duct Stones in Korea.

    Science.gov (United States)

    Song, Myung Eun; Chung, Moon Jae; Lee, Dong Jun; Oh, Tak Geun; Park, Jeong Youp; Bang, Seungmin; Park, Seung Woo; Song, Si Young; Chung, Jae Bock

    2016-01-01

    Cholecystectomy in patients with an intact gallbladder after endoscopic removal of stones from the common bile duct (CBD) remains controversial. We conducted a case-control study to determine the risk of recurrent CBD stones and the benefit of cholecystectomy for prevention of recurrence after endoscopic removal of stones from the CBD in Korean patients. A total of 317 patients who underwent endoscopic CBD stone extraction between 2006 and 2012 were included. Possible risk factors for the recurrence of CBD stones including previous cholecystectomy history, bile duct diameter, stone size, number of stones, stone composition, and the presence of a periampullary diverticulum were analyzed. The mean duration of follow-up after CBD stone extraction was 25.4±22.0 months. A CBD diameter of 15 mm or larger [odds ratio (OR), 1.930; 95% confidence interval (CI), 1.098 to 3.391; p=0.022] and the presence of a periampullary diverticulum (OR, 1.859; 95% CI, 1.014 to 3.408; p=0.045) were independent predictive factors for CBD stone recurrence. Seventeen patients (26.6%) in the recurrence group underwent elective cholecystectomy soon after endoscopic extraction of CBD stones, compared to 88 (34.8%) in the non-recurrence group; the difference was not statistically significant (p=0.212). A CBD diameter of 15 mm or larger and the presence of a periampullary diverticulum were found to be potential predictive factors for recurrence after endoscopic extraction of CBD stones. Elective cholecystectomy after clearance of CBD stones did not reduce the incidence of recurrent CBD stones in Korean patients.

  8. The demonstration of gall stones by sonography and radiography

    International Nuclear Information System (INIS)

    Gladisch, R.; Deininger, H.K.; Staedtische Kliniken Darmstadt

    1983-01-01

    Eighty-seven unselected gall stones were examined radiologically and by ultrasound in vitro. No relationship of diagnostic value could be established between the amount of calcification and stone demonstration, the sonogram being influenced by the size of the stone, its surface contour and its position in the ultrasound beam. Sonography is therefore not suitable for selecting those patients on whom litholysis could be carried out. Sonography appears to be useful only in a negative way by establishing the exact size of the concretion. (orig.) [de

  9. A comparison of nifedipine and tamsulosin as medical expulsive therapy for the management of lower ureteral stones without ESWL.

    Science.gov (United States)

    Cao, Dehong; Yang, Lu; Liu, Liangren; Yuan, Haichao; Qian, Shenqiang; Lv, Xiao; Han, Pin; Wei, Qiang

    2014-06-11

    Administration of nifedipine or tamsulosin has been suggested to augment stone expulsion rates. We aimed to compare the stone expulsion rates and adverse effects associated with the use of nifedipine or tamsulosin as medical expulsive therapy (MET) for the management of lower ureteral stones (LUS) without extracorporeal shock wave lithotripsy (ESWL) via a literature review and meta-analysis. Relevant randomized controlled trials (RCTs) were identified from the Medline, EMBASE, Cochrane CENTRAL, and Google Scholar databases. Finally, a total of 7 RCTs with 3897 patients were included. Our meta-analysis showed that tamsulosin could significantly increase the stone expulsion rate relative to nifedipine in patients with LUS (random-effects model; risk ratio [RR] = 0.81; 95% confidence interval [CI] = 0.75-0.88; P < 0.00001). The subgroup analysis indicated no statistically significant difference between the drugs with regard to minor or major adverse effects (fixed-effect model; RR = 1.19, 95% CI = 0.91-1.54, P = 0.20; and RR = 1.63, 95% CI = 0.22-11.82, P = 0.63, respectively). This meta-analysis demonstrated that tamsulosin was more effective than nifedipine in patients with LUS, as evidenced by the higher stone expulsion rate. Tamsulosin treatment should therefore be considered for patients with LUS.

  10. The effectiveness of ESWL in the management of lower pole kidney stones

    Directory of Open Access Journals (Sweden)

    Tufan Süelözgen

    2015-03-01

    Full Text Available Objective: The developments in the endourological treatments of urinary system stone diseases led to the discussions about the first choice treatment methods. We have evaluated the results of extracorporeal shock wave treatments being applied in our clinics for the lower pole stones which has the most of the those discussions. Methods: The records of 271 stone patients who were applied ESWL according to CT results between January 2013 and July 2013 to our clinics were examined. In the controls after the procedure, who could not be evaluated with the non-contrast computerized tomography (CT and ESWL treatment not completed, were excluded from the study. 52 patients with lower pole stone in total were divided into two according to the success of the ESWL treatment. ESWL success or unsuccessful groups, the size of the stone, density of the stone and the distance between the stone and skin was recorded by examining the abdominal non-contrast computed tomography (CT of the patient. Results: Of all, 28 of the patients in the study (54% were male and 24 of them (46% were female. The average age was 46±12.3 (21-73 years. Among the 52 patients included in the study after ESWL treatment, the stones of the 24 patients (46.2% were successfully treated. ESWL treatment was unsuccessful in total 28 patients (53.8%. The average size of the stone was 9.8 mm (6-17 mm, the distance between the stone and the skin was 93 mm in average (50-140. The stone density was measured as 845 HU (353-1600. Conclusion: The ESWL treatment is still a noninvasive and successful method for the lower pole kidney stones. While the ESWL success is being determined, the imaging method chosen is important, the use of abdominal CT provides accurate evaluation. The higher success rates of minimal invasive surgery methods is promising and might change the treatment methods in the future.

  11. A simulation-optimization model for Stone column-supported embankment stability considering rainfall effect

    International Nuclear Information System (INIS)

    Deb, Kousik; Dhar, Anirban; Purohit, Sandip

    2016-01-01

    Landslide due to rainfall has been and continues to be one of the most important concerns of geotechnical engineering. The paper presents the variation of factor of safety of stone column-supported embankment constructed over soft soil due to change in water level for an incessant period of rainfall. A combined simulation-optimization based methodology has been proposed to predict the critical surface of failure of the embankment and to optimize the corresponding factor of safety under rainfall conditions using an evolutionary genetic algorithm NSGA-II (Non-Dominated Sorted Genetic Algorithm-II). It has been observed that the position of water table can be reliably estimated with varying periods of infiltration using developed numerical method. The parametric study is presented to study the optimum factor of safety of the embankment and its corresponding critical failure surface under the steady-state infiltration condition. Results show that in case of floating stone columns, period of infiltration has no effect on factor of safety. Even critical failure surfaces for a particular floating column length remain same irrespective of rainfall duration

  12. A simulation-optimization model for Stone column-supported embankment stability considering rainfall effect

    Energy Technology Data Exchange (ETDEWEB)

    Deb, Kousik, E-mail: kousik@civil.iitkgp.ernet.in [Associate Professor, Department of Civil Engineering, IIT Kharagpur, Kharagpur-721302 (India); Dhar, Anirban, E-mail: anirban@civil.iitkgp.ernet.in [Assistant Professor, Department of Civil Engineering, IIT Kharagpur, Kharagpur-721302 (India); Purohit, Sandip, E-mail: sandip.purohit91@gmail.com [Former B.Tech Student, Department of Civil Engineering, NIT Rourkela, Rourkela (India)

    2016-02-01

    Landslide due to rainfall has been and continues to be one of the most important concerns of geotechnical engineering. The paper presents the variation of factor of safety of stone column-supported embankment constructed over soft soil due to change in water level for an incessant period of rainfall. A combined simulation-optimization based methodology has been proposed to predict the critical surface of failure of the embankment and to optimize the corresponding factor of safety under rainfall conditions using an evolutionary genetic algorithm NSGA-II (Non-Dominated Sorted Genetic Algorithm-II). It has been observed that the position of water table can be reliably estimated with varying periods of infiltration using developed numerical method. The parametric study is presented to study the optimum factor of safety of the embankment and its corresponding critical failure surface under the steady-state infiltration condition. Results show that in case of floating stone columns, period of infiltration has no effect on factor of safety. Even critical failure surfaces for a particular floating column length remain same irrespective of rainfall duration.

  13. Extracorporeal shockwave lithotripsy vs. percutaneous nephrolithotomy vs. flexible ureterorenoscopy for lower-pole stones

    Science.gov (United States)

    Knoll, Thomas; Buchholz, Noor; Wendt-Nordahl, Gunnar

    2012-01-01

    Objectives To review previous reports and discuss current trends in extracorporeal shockwave lithotripsy (ESWL), percutaneous nephrolithotomy (PCNL) and ureterorenoscopy (URS). ESWL was recommended as the first-line treatment for small and intermediate-sized stones in the lower pole, while it is the standard treatment for large stones. However, the stone clearance rate after ESWL seems to be lower than that of stones in other locations. This seems to result from a lower rate of fragment passage, due to anatomical factors. Methods Reports on urinary stone disease were reviewed, assessing only publications in peer-reviewed, Medline-listed journals in the English language (publication years 1990–2011). Results Recent experience with flexible URS (fURS) for intrarenal stones showed that excellent stone-free rates can be achieved. With increasing experience and technically improved equipment, fURS has become an alternative to ESWL for small and intermediate-sized renal stones. Furthermore, several authors reported successful retrograde treatment for large renal stones, proposing fURS as an alternative to PCNL. However, the major drawbacks are long operating times and commonly, staged procedures, which is why PCNL remains the method of choice for such stones. Conclusions Considering the currents trends and evidence, the 2012 update of the European Association of Urology Guidelines on Urolithiasis has upgraded the endourological treatment of kidney stones. Individual factors such as body habitus, renal anatomy, costs and patient preference must be considered. PMID:26558046

  14. Natural Stone Cluster and Valorpedra Association in Portugal: Collective efficiency, promotion and marketing strategies in the appreciation of the Dimension Stones production chain in Portugal

    OpenAIRE

    Lopes, Luís; Peres, Marta; Cristo, Nelson; Bonito, Nuno; Palma, Filipe; Goulão, Miguel

    2014-01-01

    The Natural Stone Cluster recognition by the Portuguese government resulted in the establishment of Valorpedra Association (VAPE). This national recognition allow development and increase competitiveness of the Dimension Stone Sector for which specific funds were available. The implemented measures potentiated networking among enterprises and development of partnership projects. VAPE is a nonprofit association that manages and promotes Natural Stone Cluster, seeking a Strategy for Collecti...

  15. [Pharmacotherapy for preventing calcium containing stone formation].

    Science.gov (United States)

    Nagata, Masao; Takayama, Tatsuya; Mugiya, Souichi; Ohzono, Seiichiro

    2011-10-01

    Many urinary tract stones consist of calcium, and has high relapse rate. Accordingly, it is very important to prevent calcium-containing stone formation. This paper describes about effects and mechanisms for Xanthine oxidase inhibitor, citrate formulation, magnesium formulation, thiazides, vitamin B(6), extract of Quercus salicina Blume and chorei-to (medical herb) . Recent new drugs and the elucidation of new metabolic pathways may lead to the development of prevention of urolithiasis.

  16. Wave boundary layer over a stone-covered bed

    DEFF Research Database (Denmark)

    Dixen, Martin; Hatipoglu, Figen; Sumer, B. Mutlu

    2008-01-01

    This paper summarizes the results of an experimental investigation on wave boundary layers over a bed with large roughness, simulating stone/rock/armour block cover on the sea bottom. The roughness elements used in the experiments were stones the size of 1.4cm and 3.85cm in one group of experiments...

  17. Effect of Hydrogen Adsorption on the Stone-Wales Transformation in Small-Diameter Carbon Nanotubes

    Science.gov (United States)

    Openov, L. A.; Podlivaev, A. I.

    2018-04-01

    The effect of hydrogenation of (4, 0) and (3, 0) carbon nanotubes on the Stone-Wales transformation is studied in the framework of the nonorthogonal tight-binding model. It is shown that the atomic hydrogen adsorption can lead to both a decrease and an increase in the barriers for the direct and inverse transformations depending on the orientation of a rotating C-C bond with respect to the nanotube axis. The characteristic times of formation and annealing the Stone-Wales defects have been estimated. The Young's moduli have been calculated.

  18. Secondary Waste Cast Stone Waste Form Qualification Testing Plan

    Energy Technology Data Exchange (ETDEWEB)

    Westsik, Joseph H.; Serne, R. Jeffrey

    2012-09-26

    The Hanford Tank Waste Treatment and Immobilization Plant (WTP) is being constructed to treat the 56 million gallons of radioactive waste stored in 177 underground tanks at the Hanford Site. The WTP includes a pretreatment facility to separate the wastes into high-level waste (HLW) and low-activity waste (LAW) fractions for vitrification and disposal. The LAW will be converted to glass for final disposal at the Integrated Disposal Facility (IDF). Cast Stone – a cementitious waste form, has been selected for solidification of this secondary waste stream after treatment in the ETF. The secondary-waste Cast Stone waste form must be acceptable for disposal in the IDF. This secondary waste Cast Stone waste form qualification testing plan outlines the testing of the waste form and immobilization process to demonstrate that the Cast Stone waste form can comply with the disposal requirements. Specifications for the secondary-waste Cast Stone waste form have not been established. For this testing plan, Cast Stone specifications are derived from specifications for the immobilized LAW glass in the WTP contract, the waste acceptance criteria for the IDF, and the waste acceptance criteria in the IDF Permit issued by the State of Washington. This testing plan outlines the testing needed to demonstrate that the waste form can comply with these waste form specifications and acceptance criteria. The testing program must also demonstrate that the immobilization process can be controlled to consistently provide an acceptable waste form product. This testing plan also outlines the testing needed to provide the technical basis for understanding the long-term performance of the waste form in the disposal environment. These waste form performance data are needed to support performance assessment analyses of the long-term environmental impact of the secondary-waste Cast Stone waste form in the IDF

  19. Association of staphylococcus cohnii subspecies urealyticum infection with recurrence of renal staghorn stone.

    Science.gov (United States)

    Shahandeh, Zahra; Shafi, Hamid; Sadighian, Farahnaz

    2015-01-01

    Stphylococcus cohnii is an organism of coagulase negative species which is considered as normal flora. However, it has been isolated from urinary tract infections and surgical prostheses but its relation with staghorn stones has not been reported, yet. A 50-years-old woman presented with left renal staghorn stone in June 2014. She had bilateral staghorn stones 7 years ago. Staphylococcus cohnii subspecies urealyticum were detected from a removed stone. After 7 years, recurrence staghorn stone in her left kidney was diagnosed and patient underwent another surgery. The patient had several attacks of cystitis during these 7 years. The results of stone and urine cultures revealed staphylococcus cohnii subspecies urealyticum. This case report emphasizes a possible association between staphylococcus cohnii subspecies urealyticum infection and recurrence renal staghhorn stone.

  20. Contemporary Management of Struvite Stones Using Combined Endourologic and Medical Treatment: Predictors of Unfavorable Clinical Outcome.

    Science.gov (United States)

    Iqbal, Muhammad Waqas; Youssef, Ramy F; Neisius, Andreas; Kuntz, Nicholas; Hanna, Jonathan; Ferrandino, Michael N; Preminger, Glenn M; Lipkin, Michael E

    2016-07-01

    Struvite stones have been associated with significant morbidity and mortality, yet there has not been a report on the medical management of struvite stones in almost 20 years. We report on the contemporary outcomes of the surgical and medical management of struvite stones in a contemporary series. A retrospective review of patients who were treated with percutaneous nephrolithotomy (PCNL) for struvite stones at Duke University Medical Center between January 2005 and September 2012 identified a total of 75 patients. Of these, 43 patients had adequate follow-up and were included in this analysis. Stone activity, defined as either stone recurrence or stone-related events, and predictors of activity were evaluated after combined surgical and medical treatment. The study included 43 patients with either pure (35%) or mixed (65%) struvite stones with a median age of 55±15 years (range 21-89 years). The stone-free rate after PCNL was 42%. Stone recurrence occurred in 23% of patients. Postoperatively, 30% of patients had a stone-related event, while 60% of residual stones remained stable with no growth after a median follow-up of 22 months (range 6-67 mos). Kidney function remained stable during follow-up. Independent predictors of stone activity included the presence of residual stones >0.4 cm(2), preoperative large stone burden (>10 cm(2)), and the presence of medical comorbidities (P<0.05). Struvite stones can be managed safely with PCNL followed by medical therapy. The majority of patients with residual fragments demonstrated no evidence of stone growth on medical therapy. With careful follow-up and medical management, kidney function can be maintained and stone morbidity can be minimized. Initial large stone burden, residual stones after surgery, and associated medical comorbidities may have deleterious effect on stone recurrence or residual stone-related events.

  1. Extracorporeal shock wave lithotripsy for renal stone with infundibular stenosis

    International Nuclear Information System (INIS)

    Lee, Won Hong; Son, Soon Yong; Kang, Seong Ho; Lee, Yong Moon; Yoon, Seok Hwan

    2006-01-01

    We analyzed retrospectively our experience to evaluate an effect of extracorporeal shock wave lithotripsy (ESWL) for renal stone with infundibular stenosis. From January 2002 to August 2005, 35 patients with renal stone with infundibular stenosis were treated with ESWL. The diagnosis of infundibular stenosis was made by intravenous pyelography or retrograde pyelography. The final follow-up check was performed by simple abdominal film or computed tomography and interview after 6 months to 24 months (mean 10 months). 7 (20.0%) of 35 patients was freed completely, but Stone free rate including less than 2 mm size was 80% (28/35). 30 (85.7%) patients became asymptomatic, 4 (11.4%) patients were continued, and 1 (2.9%) patient was required the percutaneous nephrostolithotomy. Although ESWL has a low complete stone free rate, We suggest that renal stone with infundibular stenosis should be treated with ESWL, because that is likely to produce a high symptom free and low complications

  2. Extracorporeal shock wave lithotripsy for renal stone with infundibular stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Won Hong; Son, Soon Yong; Kang, Seong Ho; Lee, Yong Moon [Asan Medical Center, Seoul (Korea, Republic of); Yoon, Seok Hwan [Dongnam Health College, Suwon (Korea, Republic of)

    2006-06-15

    We analyzed retrospectively our experience to evaluate an effect of extracorporeal shock wave lithotripsy (ESWL) for renal stone with infundibular stenosis. From January 2002 to August 2005, 35 patients with renal stone with infundibular stenosis were treated with ESWL. The diagnosis of infundibular stenosis was made by intravenous pyelography or retrograde pyelography. The final follow-up check was performed by simple abdominal film or computed tomography and interview after 6 months to 24 months (mean 10 months). 7 (20.0%) of 35 patients was freed completely, but Stone free rate including less than 2 mm size was 80% (28/35). 30 (85.7%) patients became asymptomatic, 4 (11.4%) patients were continued, and 1 (2.9%) patient was required the percutaneous nephrostolithotomy. Although ESWL has a low complete stone free rate, We suggest that renal stone with infundibular stenosis should be treated with ESWL, because that is likely to produce a high symptom free and low complications.

  3. Daily Cycle of Air Temperature and Surface Temperature in Stone Forest

    Science.gov (United States)

    Wang, K.; Li, Y.; Wang, X.; Yuan, M.

    2013-12-01

    Urbanization is one of the most profound human activities that impact on climate change. In cities, where are highly artificial areas, the conflict between human activity and natural climate is particularly prominent. Urban areas always have the larger area of impervious land, the higher consumption of greenhouse gases, more emissions of anthropogenic heat and air pollution, all contribute to the urban warming phenomena. Understanding the mechanisms causing a variety of phenomena involved in the urban warming is critical to distinguish the anthropogenic effect and natural variation in the climate change. However, the exact dynamics of urban warming were poorly understood, and effective control strategies are not available. Here we present a study of the daily cycle of air temperature and surface temperature in Stone Forest. The specific heat of the stones in the Stone Forest and concrete of the man-made structures within the cities are approximate. Besides, the height of the Stone Forest and the height of buildings within the city are also similar. As a scenic area, the Stone Forest is being preserved and only opened for sightseeing. There is no anthropogenic heat, as well air pollution within the Stone Forest. The thermal environment in Stone Forest can be considered to be a simulation of thermal environment in the city, which can reveal the effect of man-made structures on urban thermal environment. We conducted the field studies and numerical analysis in the Stone Forest for 4 typical urban morphology and environment scenarios, including high-rise compact cities, low-rise sparse cities, garden cities and isolated single stone. Air temperature and relative humidity were measured every half an hour in 15 different locations, which within different spatial distribution of stones and can represent the four urban scenarios respectively. At the same time, an infrared camera was used to take thermal images and get the hourly surface temperatures of stones and

  4. A comparison of nifedipine and tamsulosin as medical expulsive therapy for the management of lower ureteral stones without ESWL

    Science.gov (United States)

    Cao, Dehong; Yang, Lu; Liu, Liangren; Yuan, Haichao; Qian, Shenqiang; Lv, Xiao; Han, Pin; Wei, Qiang

    2014-01-01

    Administration of nifedipine or tamsulosin has been suggested to augment stone expulsion rates. We aimed to compare the stone expulsion rates and adverse effects associated with the use of nifedipine or tamsulosin as medical expulsive therapy (MET) for the management of lower ureteral stones (LUS) without extracorporeal shock wave lithotripsy (ESWL) via a literature review and meta-analysis. Relevant randomized controlled trials (RCTs) were identified from the Medline, EMBASE, Cochrane CENTRAL, and Google Scholar databases. Finally, a total of 7 RCTs with 3897 patients were included. Our meta-analysis showed that tamsulosin could significantly increase the stone expulsion rate relative to nifedipine in patients with LUS (random-effects model; risk ratio [RR] = 0.81; 95% confidence interval [CI] = 0.75–0.88; P tamsulosin was more effective than nifedipine in patients with LUS, as evidenced by the higher stone expulsion rate. Tamsulosin treatment should therefore be considered for patients with LUS. PMID:24919112

  5. Morphology of Major Stone Types, As Shown by Micro Computed Tomography (micro CT)

    International Nuclear Information System (INIS)

    Jackson, Molly E.; Beuschel, Christian A.; McAteer, James A.; Williams, James C.

    2008-01-01

    Micro CT offers the possibility of providing a non-destructive method of stone analysis that allows visualization of 100% of the stone's volume. For the present study, micro CT analysis was completed on stones of known composition with isotropic voxel sizes of either 7 or 9.1 μm. Each mineral type was distinctive, either by x-ray attenuation values or by morphology. Minor components, such as the presence of apatite in oxalate stones, were easily seen. The analysis of stones by micro CT opens up the possibility of exploring the stone as an encapsulated history of the patient's disease, showing changes in mineral deposition with time.

  6. Protecting of Marble Stone Facades of Historic Buildings Using Multifunctional TiO2 Nanocoatings

    Directory of Open Access Journals (Sweden)

    Mohammad A. Aldoasri

    2017-11-01

    Full Text Available Stone surfaces and façades of historic buildings, due to their predominately outdoor location, suffer from many deterioration factors, including air pollution, soluble salts, relative humidity (RH/temperature, and biodeterioration, which are the main causes of decay. In particular, the façades of the buildings deteriorate with direct exposure to these factors; deformation and disfiguration of superficial decoration and formation of black crusts are often observed on the stones. The development and application of self-cleaning and protection treatments on historical and architectural stone surfaces could be a significant improvement in the conservation, protection and maintenance of Cultural Heritage. A titanium dioxide nanoparticle has become a promising photocatalytic material, owing to its ability to catalyze the complete degradation of many organic contaminants and environmental factors. In this study, TiO2 nanoparticles, dispersed in an aqueous colloidal suspension, were applied directly to historic marble stone surfaces, by spray-coating, in order to obtain a nanometric film over the stone surface. The study started with an investigation of some properties of TiO2 nanoparticles, to assess the feasibility of the use of TiO2 on historic stone and architectural surfaces. Scanning electron microscopy (SEM was, coupled with energy dispersive X-ray (EDX microanalysis, (SEM-EDX, in order to obtain information on coating homogeneity and surface morphology, before and after artificial aging; the activity of the coated surface was evaluated through UV-light exposure, to evaluate photo-induced effects. The changes of molecular structure occurring in treated samples were spectroscopically studied by attenuated total reflection infrared spectroscopy (ATR-FTIR; activity of the hydrophobic property of the coated surface was evaluated by Sterio microscopy, model Zeiss 2010 from Munich, Germany, equipped with photo camera S23 under 80X magnification. The

  7. Luminescence dating of anthropogenic features of the San Luis Valley, Colorado: from stone huts to stone walls

    Science.gov (United States)

    Mahan, Shannon; Donlan, Rebecca A.; Kardos, Barbara Maat

    2015-01-01

    The Snake Nest Wall site and the Crestone Stone Huts are in the northern San Luis Valley, Colorado, and provide a unique opportunity to date high-altitude archeological sites of unknown age and origin using optically stimulated luminescence (OSL). We sampled sediment underlying foundation stones of these structures to establish a chronological framework for each site's construction. OSL dating of the quartz grains directly under the Snake Nest Wall suggest that the stones and, therefore, the structure was most recently emplaced between 1855 and 1890 A.D. Dating of the sediment beneath the Crestone Stone Huts suggests the construction time of these huts is between 1860 and 1890 A.D. Analysis of the equivalent dose (DE) dispersion of the OSL samples at Snake Nest Wall and the Crestone Huts shows that the majority of sediments were fully bleached prior to deposition and the low scatter suggests that short-term or shallow alluvial processes were the dominant transport for sediments. In both cases, the OSL ages show that the construction was during very recent historical times, although it is likely that the Snake Nest Wall was rebuilt in the late 19th century. Further study is warranted at the Snake Nest Wall since it shows signs of greater antiquity and a continued presence of human use. The Crestone Huts are shown to be a product of railroad building during the boomtown days of Lucky and Crestone.

  8. Stone fragmentation by ultrasound

    Indian Academy of Sciences (India)

    Unknown

    In the present work, enhancement of the kidney stone fragmentation by using ultrasound is studied. The cavi- ... ment system like radiation pressure balance, the power is given by ... Thus the bubble size has direct relationship with its life and.

  9. Calcium Oxalate Stones Are Frequently Found Attached to Randall's Plaque

    International Nuclear Information System (INIS)

    Matlaga, Brian R.; Williams, James C. Jr.; Evan, Andrew P.; Lingeman, James E.

    2007-01-01

    The exact mechanisms of the crystallization processes that occur during the formation of calcium oxalate calculi are controversial. Over six decades ago, Alexander Randall reported on a series of cadaveric renal units in which he observed calcium salt deposits on the tips of the renal papilla. Randall hypothesized that these deposits, eponymously termed Randall's plaque, would be the ideal site for stone formation, and indeed in a number of specimens he noted small stones attached to the papillae. With the recent advent of digital endoscopic imaging and micro computerized tomography (CT) technology, it is now possible to inspect the renal papilla of living, human stone formers and to study the attached stone with greater scrutiny

  10. Crushed stone production plant for NPP building

    International Nuclear Information System (INIS)

    Obolenskij, V.Ya.

    1982-01-01

    The project of the granite-crushed stone quarry - the large modern plant producing building materials, is presented. The quarry is designated for providing NPP and other power objects building with high-strength crushed stone. The plant consists of: quarry; crushing-sorting plant with maintenance objects arranged on its ground; basis and service stores of explosive materials; tail facility and purifying systems; water supply purifying stations; water storage basin. The plant is reserved for 2335 thousand m 3 yearly utoput of crushed stone; the staff consists of 535 persons, the budgeted cost of building is 26.6 million rubles. Physicochemical characteristics of granosyenites of the ''Granitnoye'' deposit - the raw material resource base of the plant and technological scheme of the crushing-sorting plant are given. Planned measures on building organization and recultivation of disturbed grounds are presented

  11. External Validation and Evaluation of Reliability and Validity of the Modified Seoul National University Renal Stone Complexity Scoring System to Predict Stone-Free Status After Retrograde Intrarenal Surgery.

    Science.gov (United States)

    Park, Juhyun; Kang, Minyong; Jeong, Chang Wook; Oh, Sohee; Lee, Jeong Woo; Lee, Seung Bae; Son, Hwancheol; Jeong, Hyeon; Cho, Sung Yong

    2015-08-01

    The modified Seoul National University Renal Stone Complexity scoring system (S-ReSC-R) for retrograde intrarenal surgery (RIRS) was developed as a tool to predict stone-free rate (SFR) after RIRS. We externally validated the S-ReSC-R. We retrospectively reviewed 159 patients who underwent RIRS. The S-ReSC-R was assigned from 1 to 12 according to the location and number of sites involved. The stone-free status was defined as no evidence of a stone or with clinically insignificant residual fragment stones less than 2 mm. Interobserver and test-retest reliabilities were evaluated. Statistical performance of the prediction model was assessed by its predictive accuracy, predictive probability, and clinical usefulness. Overall SFR was 73.0%. The SFRs were 86.7%, 70.2%, and 48.6% in low-score (1-2), intermediate-score (3-4), and high-score (5-12) groups, respectively (pR revealed an area under the curve (AUC) of 0.731 (95% CI 0.650-0.813). The AUC of the three-titered S-ReSC-R was 0.701 (95% CI 0.609-0.794). The calibration plot showed that the predicted probability of SFR had a concordance comparable to that of observed frequency. The Hosmer-Lemeshow goodness of fit test revealed a p-value of 0.01 for the S-ReSC-R and 0.90 for the three-titered S-ReSC-R. Interobserver and test-retest reliabilities revealed an almost perfect level of agreement. The present study proved the predictive value of S-ReSC-R to predict SFR following RIRS in an independent cohort. Interobserver and test-retest reliabilities confirmed that S-ReSC-R was reliable and valid.

  12. THE OPTIMIZATION OF TECHNOLOGICAL MINING PARAMETERS IN QUARRY FOR DIMENSION STONE BLOCKS QUALITY IMPROVEMENT BASED ON PHOTOGRAMMETRIC TECHNIQUES OF MEASUREMENT

    Directory of Open Access Journals (Sweden)

    Ruslan Sobolevskyi

    2018-01-01

    Full Text Available This research focuses on patterns of change in the dimension stone commodity blocks quality production on previously identifi ed and measured geometrical parameters of natural cracks, modelling and planning out the fi nal dimension of stone products and fi nished products based on the proposed digital photogrammetric techniques. The optimal parameters of surveying are investigated and the infl uence of surveying distance to length and crack area is estimated. Rational technological parameters of dimension stone blocks production are taken into account.

  13. The building stones of ancient Egypt a gift of its geology

    Science.gov (United States)

    Klemm, Dietrich D.; Klemm, Rosemarie

    2001-08-01

    Building stones and clay-rich Nile mud were ancient Egypt's main raw construction materials. While the mud was easily accessible along the Nile river valley, the immense quantities of the different stone materials used for construction of the famous pyramids, precious temples and tombs needed a systematic quarrying organization, well arranged transport logistics over extreme distances and a high standard of stone masonry. The petrography, occurrence, and main applications of the 11 most popular stone types used in ancient Egypt are described in this contribution. Rough estimates of the scale of this mining activity, based on the volume of many different ancient quarry sites, all over Egypt, reveal that the monuments known today represent only a small fraction of the amount of building stones mined during the long, ancient Egyptian history.

  14. Relationship Between Ureteral Jet Flow, Visual Analogue Scale, and Ureteral Stone Size.

    Science.gov (United States)

    Ongun, Sakir; Teken, Abdurrazak; Yılmaz, Orkun; Süleyman, Sakir

    2017-06-01

    To contribute to the diagnosis and treatment of ureteral stones by investigating the relationship between the ureteral jet flow measurements of patients with ureteral stones and the size of the stones and the patients' pain scores. The sample consisted of patients who presented acute renal colic between December 2014 and 2015 and from a noncontrast computed tomography were found to have a urinary stone. The ureteral jet flow velocities were determined using Doppler ultrasonography. The patients were all assessed in terms of stone size, localization and area, anteroposterior pelvis (AP) diameter, and visual analogue scale (VAS) scores. A total of 102 patients were included in the study. As the VAS score decreased, the peak jet flow velocity on the stone side increased, whereas the flow velocity on the other side, AP diameter, and stone area were reduced (P flow velocity was reduced and the AP diameter increased significantly (P flow was not observed in 17 patients on the stone side. A statistically significant difference was found between these patients and the remaining patients in terms of all parameters (P flow velocity of ureteral jet is low and with a severe level of pain or the peak flow velocity of ureteral jet cannot be measured, there is a low possibility of spontaneous passage and a high possibility of a large stone, and therefore the treatment should be started immediately. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Coronal reconstruction of unenhanced abdominal CT for correct ureteral stone size classification

    Energy Technology Data Exchange (ETDEWEB)

    Berkovitz, Nadav; Simanovsky, Natalia; Hiller, Nurith [Hadassah Mount Scopus - Hebrew University Medical Center, Department of Radiology, Jerusalem (Israel); Katz, Ran [Hadassah Mount Scopus - Hebrew University Medical Center, Department of Urology, Jerusalem (Israel); Salama, Shaden [Hadassah Mount Scopus - Hebrew University Medical Center, Department of Emergency Medicine, Jerusalem (Israel)

    2010-05-15

    To determine whether size measurement of a urinary calculus in coronal reconstruction of computed tomography (CT) differs from stone size measured in the axial plane, and whether the difference alters clinical decision making. We retrospectively reviewed unenhanced CT examinations of 150 patients admitted to the emergency room (ER) with acute renal colic. Maximal ureteral calculus size was measured on axial slices and coronal reconstructions. Clinical significance was defined as an upgrading or downgrading of stone size according to accepted thresholds of treatment: {<=}5 mm, 6-9 mm and {>=}10 mm. There were 151 stones in 150 patients (male:female 115:34, mean age 41 years). Transverse stone diameters ranged from 1 to 11 mm (mean 4 mm). On coronal images, 56 (37%) stones were upgraded in severity; 46 (30%) from below 5 mm to 6 mm or more, and ten (7%) from 6-9 mm to 10 mm or more. Transverse measurement on the axial slices enabled correct categorization of 95 stones (63%). Transverse calculus measurement on axial slices often underestimates stone size and provides incorrect clinical classification of the true maximal stone diameter. Coronal reconstruction provides additional information in patients with renal colic that may alter treatment strategy. (orig.)

  16. Coronal reconstruction of unenhanced abdominal CT for correct ureteral stone size classification

    International Nuclear Information System (INIS)

    Berkovitz, Nadav; Simanovsky, Natalia; Hiller, Nurith; Katz, Ran; Salama, Shaden

    2010-01-01

    To determine whether size measurement of a urinary calculus in coronal reconstruction of computed tomography (CT) differs from stone size measured in the axial plane, and whether the difference alters clinical decision making. We retrospectively reviewed unenhanced CT examinations of 150 patients admitted to the emergency room (ER) with acute renal colic. Maximal ureteral calculus size was measured on axial slices and coronal reconstructions. Clinical significance was defined as an upgrading or downgrading of stone size according to accepted thresholds of treatment: ≤5 mm, 6-9 mm and ≥10 mm. There were 151 stones in 150 patients (male:female 115:34, mean age 41 years). Transverse stone diameters ranged from 1 to 11 mm (mean 4 mm). On coronal images, 56 (37%) stones were upgraded in severity; 46 (30%) from below 5 mm to 6 mm or more, and ten (7%) from 6-9 mm to 10 mm or more. Transverse measurement on the axial slices enabled correct categorization of 95 stones (63%). Transverse calculus measurement on axial slices often underestimates stone size and provides incorrect clinical classification of the true maximal stone diameter. Coronal reconstruction provides additional information in patients with renal colic that may alter treatment strategy. (orig.)

  17. Flexible ureterorenoscopy for lower pole stones: influence of the collecting system's anatomy.

    Science.gov (United States)

    Jessen, Jan Peter; Honeck, Patrick; Knoll, Thomas; Wendt-Nordahl, Gunnar

    2014-02-01

    The impact of renal anatomy on the success rate of flexible ureterorenoscopy (fURS) for lower pole stones is less clear than it is on shock wave lithotripsy, for which it is a recognized influence factor. We analyzed safety and efficiency of fURS using modern endoscopes for lower pole stones dependent on the collecting system's configuration. We retrospectively evaluated a consecutive sample of 111 fURS for lower pole stones at our tertiary care center between January 2010 and September 2012 from our prospectively kept database. All procedures were performed with modern flexible ureterorenoscopes, nitinol baskets, holmium laser lithotripsy, and ureteral access sheaths whenever needed. The infundibular length (IL) and width (IW) and infundibulopelvic angle (IPA) were measured and the data were stratified for stone-free status and complications classified by the Clavien-Dindo scale. Univariate and multifactorial statistical analyses were performed. Correlation of operation time (OR-time) with anatomical parameters was conducted. Ninety-eight (88.3%) of the 111 patients were stone free after a single fURS. On multifactorial analysis, the stone size and IL had significant influence on the stone-free rate (SFR) (panatomy. fURS is a safe and efficient treatment option for lower pole kidney stones. A long infundibulum and a very acute IPA (anatomy.

  18. Percutaneous treatment of extrahepatic bile duct stones assisted by balloon sphincteroplasty and occlusion balloon

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yong Sung; Kim, Ji Hyung; Choi, Young Woo; Lee, Tae Hee; Hwang, Cheol Mog; Cho, Young Jun; Kim, Keum Won [Konyang University Hospital, Daejeon (Korea, Republic of)

    2005-12-15

    To describe the technical feasibility and usefulness of extrahepatic biliary stone removal by balloon sphincteroplasty and occlusion balloon pushing. Fifteen patients with extrahepatic bile duct stones were included in this study. Endoscopic stone removal was not successful in 13 patients, and two patients refused the procedure due to endoscopy phobia. At first, all patients underwent percutaneous transhepatic biliary drainage (PTBD). A few days later, through the PTBD route, balloon assisted dilatation for common bile duct (CBD) sphincter was performed, and then the stones were pushed into the duodenum using an 11.5 mm occlusion balloon. Success rate, reason for failure, and complications associated with the procedure were evaluated. Eight patients had one stone, five patients had two stones, and two patients had more than five stones. The procedure was successful in 13 patients (13/15). In 12 of the patients, all stones were removed in the first trial. In one patients, residual stones were discovered on follow-up cholangiography, and were subsequently removed in the second trial. Technical failure occurred in two patients. Both of these patients had severely dilated CBD and multiple stones with various sizes. Ten patients complained of pain in the right upper quadrant and epigastrium of the abdomen immediately following the procedure, but there were no significant procedure-related complications such as bleeding or pancreatitis. Percutaneous extrahepatic biliary stone removal by balloon sphincteroplasty and subsequent stone pushing with occlusion balloon is an effective, safe, and technically feasible procedure which can be used as an alternative method in patients when endoscopic extrahepatic biliary stone removal was not successful.

  19. Percutaneous treatment of extrahepatic bile duct stones assisted by balloon sphincteroplasty and occlusion balloon

    International Nuclear Information System (INIS)

    Park, Yong Sung; Kim, Ji Hyung; Choi, Young Woo; Lee, Tae Hee; Hwang, Cheol Mog; Cho, Young Jun; Kim, Keum Won

    2005-01-01

    To describe the technical feasibility and usefulness of extrahepatic biliary stone removal by balloon sphincteroplasty and occlusion balloon pushing. Fifteen patients with extrahepatic bile duct stones were included in this study. Endoscopic stone removal was not successful in 13 patients, and two patients refused the procedure due to endoscopy phobia. At first, all patients underwent percutaneous transhepatic biliary drainage (PTBD). A few days later, through the PTBD route, balloon assisted dilatation for common bile duct (CBD) sphincter was performed, and then the stones were pushed into the duodenum using an 11.5 mm occlusion balloon. Success rate, reason for failure, and complications associated with the procedure were evaluated. Eight patients had one stone, five patients had two stones, and two patients had more than five stones. The procedure was successful in 13 patients (13/15). In 12 of the patients, all stones were removed in the first trial. In one patients, residual stones were discovered on follow-up cholangiography, and were subsequently removed in the second trial. Technical failure occurred in two patients. Both of these patients had severely dilated CBD and multiple stones with various sizes. Ten patients complained of pain in the right upper quadrant and epigastrium of the abdomen immediately following the procedure, but there were no significant procedure-related complications such as bleeding or pancreatitis. Percutaneous extrahepatic biliary stone removal by balloon sphincteroplasty and subsequent stone pushing with occlusion balloon is an effective, safe, and technically feasible procedure which can be used as an alternative method in patients when endoscopic extrahepatic biliary stone removal was not successful

  20. Specification of a STEP Based Reference Model for Exchange of Robotics Models

    DEFF Research Database (Denmark)

    Haenisch, Jochen; Kroszynski, Uri; Ludwig, Arnold

    robot programming, the descriptions of geometry, kinematics, robotics, dynamics, and controller data using STEP are addressed as major goals of the project.The Project Consortium has now released the "Specificatin of a STEP Based Reference Model for Exchange of Robotics Models" on which a series......ESPRIT Project 6457: "Interoperability of Standards for Robotics in CIME" (InterRob) belongs to the Subprogram "Computer Integrated Manufacturing and Engineering" of ESPRIT, the European Specific Programme for Research and Development in Information Technology supported by the European Commision....... InterRob aims to develop an integrated solution to precision manufacturing by combining product data and database technologies with robotic off-line programming and simulation. Benefits arise from the use of high level simulation tools and developing standards for the exchange of product model data...

  1. Bacteriological study and structural composition of staghorn stones removed by the anatrophic nephrolithotomic procedure

    Directory of Open Access Journals (Sweden)

    Hamid Shafi

    2013-01-01

    Full Text Available This study was conducted to determine the composition of staghorn stones and to assess the proportion of infected stones as well as the correlation between infection in the stones and bacteria grown in urine. Samples of 45 consecutive stones removed through anatrophic nephrolithotomic procedures were taken from the operation site and samples of urine were obtained by simultaneous bladder catheterization. The frequency of infection in the stones and correlation between infection of stone and urine samples were determined with respect to the composition of the stones. Twenty-two males and 23 females, with respective mean ages of 48.3 ± 15.6 years and 51 ± 7.4 years, were studied. The stone and urine cultures yielded positive results in ten and 16 patients, respectively, of a total of 45 patients (22.2% and 35.5%, respectively. Calcium oxalate was the main constituent of staghorn stones, seen in 31 patients (68.8%, uric acid in 12 patients (26.6% and struvite and/or calcium phosphate in 11 patients (24.4%. In seven of ten stones with bacterial growth, bacteria were isolated from urine cultures as well, which accounted for a concordance rate of 70%. The bacteria grown in the stone were the cause of urinary tract infection (UTI in 43.5% of the cases. Stone infection was significantly associated with UTI (OR = 6.47; 95% CI 1.43-31.7, P = 0.021 and presence of phosphate in the stones (OR = 18, 95% CI 3.28-99.6, P = 0.0006. E. coli was the most common bacteria grown from the stones, and was isolated in 50% of the cases; Ureaplasma urealyticum was the most common organism causing UTI, grown in 62.5% of the urine samples. There was a high concordance rate between bacteria in the stones and urine. These findings indicate that the urine culture can provide information for selection of an appropriate anti-microbial agent for stone sterilization. In addition, preventing re-growth or recurrence of stones and treatment of post-surgical infections would be

  2. Lunar Polar In Situ Resource Utilization (ISRU) as a Stepping Stone for Human Exploration

    Science.gov (United States)

    Sanders, Gerald B.

    2013-01-01

    A major emphasis of NASA is to extend and expand human exploration across the solar system. While specific destinations are still being discussed as to what comes first, it is imperative that NASA create new technologies and approaches that make space exploration affordable and sustainable. Critical to achieving affordable and sustainable exploration beyond low Earth orbit (LEO) are the development of technologies and approaches for advanced robotics, power, propulsion, habitats, life support, and especially, space resource utilization systems. Space resources and how to use them, often called In-Situ Resource Utilization (ISRU), can have a tremendous beneficial impact on robotic and human exploration of the Moon, Mars, Phobos, and Near Earth Objects (NEOs), while at the same time helping to solve terrestrial challenges and enabling commercial space activities. The search for lunar resources, demonstration of extraterrestrial mining, and the utilization of resource-derived products, especially from polar volatiles, can be a stepping stone for subsequent human exploration missions to other destinations of interest due to the proximity of the Moon, complimentary environments and resources, and the demonstration of critical technologies, processes, and operations. ISRU and the Moon: There are four main areas of development interest with respect to finding, obtaining, extracting, and using space resources: Prospecting for resources, Production of mission critical consumables like propellants and life support gases, Civil engineering and construction, and Energy production, storage, and transfer. The search for potential resources and the production of mission critical consumables are the primary focus of current NASA technology and system development activities since they provide the greatest initial reduction in mission mass, cost, and risk. Because of the proximity of the Moon, understanding lunar resources and developing, demonstrating, and implementing lunar ISRU

  3. Sulfate but not thiosulfate reduces calculated and measured urinary ionized calcium and supersaturation: implications for the treatment of calcium renal stones.

    Directory of Open Access Journals (Sweden)

    Allen Rodgers

    Full Text Available Urinary sulfate (SO4(2- and thiosulfate (S2O3(2- can potentially bind with calcium and decrease kidney stone risk. We modeled the effects of these species on the concentration of ionized calcium (iCa and on supersaturation (SS of calcium oxalate (CaOx and calcium phosphate (CaP, and measured their in vitro effects on iCa and the upper limit of stability (ULM of these salts.Urine data from 4 different types of stone patients were obtained from the Mayo Nephrology Clinic (Model 1. A second data set was obtained from healthy controls and hypercalciuric stone formers in the literature who had been treated with sodium thiosulfate (STS (Model 2. The Joint Expert Speciation System (JESS was used to calculate iCa and SS. In Model 1, these parameters were calculated as a function of sulfate and thiosulfate concentrations. In Model 2, data from pre- and post STS urines were analyzed. ULM and iCa were determined in human urine as a function of sulfate and thiosulfate concentrations.Calculated iCa and SS values for all calcium salts decreased with increasing sulfate concentration. Thiosulfate had no effect on these parameters. In Model 2, calculated iCa and CaOx SS increased after STS treatment, but CaP SS decreased, perhaps due to a decrease in pH after STS treatment. In confirmatory in vitro experiments supplemental sulfate, but not thiosulfate, significantly increased the calcium needed to achieve the ULM of CaP and tended to increase the oxalate needed to reach the ULM of CaOx. Sulfate also significantly decreased iCa in human urine, while thiosulfate had no effect.Increasing urinary sulfate could theoretically reduce CaOx and CaP stone risk. Although STS may reduce CaP stone risk by decreasing urinary pH, it might also paradoxically increase iCa and CaOx SS. As such, STS may not be a viable treatment option for stone disease.

  4. An adaptive time-stepping strategy for solving the phase field crystal model

    International Nuclear Information System (INIS)

    Zhang, Zhengru; Ma, Yuan; Qiao, Zhonghua

    2013-01-01

    In this work, we will propose an adaptive time step method for simulating the dynamics of the phase field crystal (PFC) model. The numerical simulation of the PFC model needs long time to reach steady state, and then large time-stepping method is necessary. Unconditionally energy stable schemes are used to solve the PFC model. The time steps are adaptively determined based on the time derivative of the corresponding energy. It is found that the use of the proposed time step adaptivity cannot only resolve the steady state solution, but also the dynamical development of the solution efficiently and accurately. The numerical experiments demonstrate that the CPU time is significantly saved for long time simulations

  5. Genomic prediction in a nuclear population of layers using single-step models.

    Science.gov (United States)

    Yan, Yiyuan; Wu, Guiqin; Liu, Aiqiao; Sun, Congjiao; Han, Wenpeng; Li, Guangqi; Yang, Ning

    2018-02-01

    Single-step genomic prediction method has been proposed to improve the accuracy of genomic prediction by incorporating information of both genotyped and ungenotyped animals. The objective of this study is to compare the prediction performance of single-step model with a 2-step models and the pedigree-based models in a nuclear population of layers. A total of 1,344 chickens across 4 generations were genotyped by a 600 K SNP chip. Four traits were analyzed, i.e., body weight at 28 wk (BW28), egg weight at 28 wk (EW28), laying rate at 38 wk (LR38), and Haugh unit at 36 wk (HU36). In predicting offsprings, individuals from generation 1 to 3 were used as training data and females from generation 4 were used as validation set. The accuracies of predicted breeding values by pedigree BLUP (PBLUP), genomic BLUP (GBLUP), SSGBLUP and single-step blending (SSBlending) were compared for both genotyped and ungenotyped individuals. For genotyped females, GBLUP performed no better than PBLUP because of the small size of training data, while the 2 single-step models predicted more accurately than the PBLUP model. The average predictive ability of SSGBLUP and SSBlending were 16.0% and 10.8% higher than the PBLUP model across traits, respectively. Furthermore, the predictive abilities for ungenotyped individuals were also enhanced. The average improvements of prediction abilities were 5.9% and 1.5% for SSGBLUP and SSBlending model, respectively. It was concluded that single-step models, especially the SSGBLUP model, can yield more accurate prediction of genetic merits and are preferable for practical implementation of genomic selection in layers. © 2017 Poultry Science Association Inc.

  6. Circular Raft Footings Strengthened by Stone Columns under Static Loads

    OpenAIRE

    R. Ziaie Moayed; B. Mohammadi-Haji

    2016-01-01

    Stone columns have been widely employed to improve the load-settlement characteristics of soft soils. The results of two small scale displacement control loading tests on stone columns were used in order to validate numerical finite element simulations. Additionally, a series of numerical calculations of static loading have been performed on strengthened raft footing to investigate the effects of using stone columns on bearing capacity of footings. The bearing capacity of single and group of ...

  7. Stability of Reshaping Breakwaters with Special Reference to Stone Durability

    OpenAIRE

    Frigaard, Peter; Hald, Tue; Burcharth, H. F.; Sigurdarson, S.

    1998-01-01

    Traditionally, conventional rubble mound breakwaters are designed with stable armour units, and consequently, very large stones or even artificial armour units are required. Reshaping breakwater designs allow reshaping of the seward slope thus involving stone movements. Ultimately, dependent on the degree of safety in the design, this reshaping process might end up in a stable profile where no changes in the cross sections occur even though stone movements are allowed.Unfortunately, large mov...

  8. Bilateral same-session ureterorenoscopy: A feasible approach to treat pan-urinary stone disease

    Directory of Open Access Journals (Sweden)

    Bora Özveren

    2017-12-01

    Full Text Available Objectives: To assess treatment effectiveness and safety of bilateral same-session ureterorenoscopy (BSSU for the management of stone disease involving the entire urinary system. Patients and methods: We reviewed the records of 64 patients who underwent BSSU for the treatment of bilateral ureteric and/or kidney stones. Size, number, location per side, and the total burden of stones were recorded. Data on stenting, lithotripsy, and stone retrieval, and details of hospital stay and operation times were investigated. Treatment results were assessed using intraoperative findings and postoperative imaging. The outcome was considered successful in patients who were completely stone-free or who had only residual fragments of ≤2 mm. Results: The outcome was successful in 82.8% of the patients who received BSSU (54.7% stone-free and 28.1% insignificant residual fragments. The success rate per renal unit was 89.8%. There were no adverse events in 73.4% of the patients. The most common intraoperative complication was mucosal injury (36%. The complications were Clavien–Dindo Grade I in 9.4% and Grade II in 7.8%. Grade IIIa and IIIb (9.4% complications required re-treatments. Statistical evaluation showed no association between complication grades and stone, patient, or operation features. Stone burden had no negative impact on BSSU results. The presence of impacted proximal ureteric stones was significantly related to unsuccessful outcomes. Conclusion: BSSU is safe and effective for the management of bilateral urolithiasis. BSSU can prevent recurrent surgeries, reduce overall hospital stay, and achieve a stone-free status and complication rates that are comparable to those of unilateral or staged bilateral procedures. Keywords: Ureteroscopy, Bilateral, Kidney stones, ureter stones, Flexible ureterorenoscopy, Treatment outcomes

  9. 'Saurashtra stone anchors' (Ring-stones) from Dwarka and Somnath, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Gaur, A.S.; Sundaresh; Tripati, S.; Gudigar, P.; Bandodkar, S.N.

    Last two decades of marine archaeological research along the Indian coast has brought to light a large number of stone anchors of different types and sizes, indicating that the Indian coast has witnessed brisk maritime activities in the past...

  10. Numerical simulation of the time-dependent deformation behaviour of clay-stone rock mass at the Tournemire site with 2D and 3D models

    International Nuclear Information System (INIS)

    Rutenberg, M.; Lux, K. H.

    2011-01-01

    Clay-stone rock masses are a reasonable alternative to e.g. salt rock masses as a host rock for underground radioactive waste repositories because of their very low permeability as well as their radionuclide retention capacity. Though clay-stone has been explored for many years, there is still a need for further research on its hydro-mechanical behaviour. Convergence measurements over a 4-year period in the tunnel system of the argillaceous Tournemire site in France yielded the presence of a time-dependent deformation behaviour in indurated clay. Moreover, a mine-by test was carried out with extensometer measurements capturing the rock mass deformation during the excavation process of a new gallery in 2003.This work focuses on the validation of a constitutive model by means of a three-dimensional (3D) simulation of the mine-by test. The utilised constitutive model Hou/Lux-T is based on the viscous constitutive model Lubby2 with which time-dependent deformation behaviour of salt rock can appropriately be simulated. It has been adapted to clay-stone by considering anisotropy effects, and in addition it features a strain-dependent fracture and failure criterion. The results of the mine-by-test simulation show that the calculated stresses and deformations in the rock mass seem to behave reasonably under this constitutive model with respect to time-dependency. A comparison of the 3D results to the results of a simplified two-dimensional (2D) simulation confirms the adequacy of using a 2D model with the constitutive model Hou/Lux-T for the setting at hand, described in the text (material parameters, time scale), in order to assess load-bearing capacity and deformability of the gallery near field away from heading face and tunnel crossing. Finally, a comparison of the 3D simulation results to the extensometer measurement results yields the principal ability of the used constitutive model to describe time-dependent evolutions of stresses and deformations during a three

  11. Step-indexed Kripke models over recursive worlds

    DEFF Research Database (Denmark)

    Birkedal, Lars; Reus, Bernhard; Schwinghammer, Jan

    2011-01-01

    worlds that are recursively defined in a category of metric spaces. In this paper, we broaden the scope of this technique from the original domain-theoretic setting to an elementary, operational one based on step indexing. The resulting method is widely applicable and leads to simple, succinct models...

  12. Usefulness of {sup 99m}Tc-DTPA renography and diuretic renography in predicting successful stone discharge following outpatient ESWL in patients with a single ureteral stone

    Energy Technology Data Exchange (ETDEWEB)

    Soga, Norihito; Komeda, Yoshinori [Yokkaichi Health Insurance Hospital, Mie (Japan); Suzuki, Ryuichi; Kawamura, Juichi

    1996-11-01

    We analyzed the {sup 99m}Tc-DTPA renogram with and without diuresis to predict the possibility of stone discharge on the outpatient basis by renogram patterns. Between October 1993 and December 1995, {sup 99m}Tc-DTPA renography was performed in 79 patients with a single ureteral stone. The {sup 99m}Tc-DTPA renogram pattern was classified into the three types of normal function, obstruction and lower function patterns and the complete stone discharge rate was 93, 63 and 25%, respectively. In addition, diuretic renography using Furosemide was performed in patients with an obstruction pattern and the three renogram patterns of return to the normal curve, a diuretic response and no response were obtained; the complete stone discharge rate was 44, 65.3 and 93%, respectively. From this study, patients with a single ureteral stone with a normal pattern on the regular DTPA renogram and patients with no response pattern on the diuretic renogram, even if in such patients an obstructive pattern was seen on the regular DTPA renogram, seem to be a good candidate for obtaining a high rate of a stone discharge with extracorporeal shock wave lithotripsy (ESWL) treatment in the outpatients basis. (author)

  13. Topological anisotropy of stone-wales waves in graphenic fragments.

    Science.gov (United States)

    Ori, Ottorino; Cataldo, Franco; Putz, Mihai V

    2011-01-01

    Stone-Wales operators interchange four adjacent hexagons with two pentagon-heptagon 5|7 pairs that, graphically, may be iteratively propagated in the graphene layer, originating a new interesting structural defect called here Stone-Wales wave. By minimization, the Wiener index topological invariant evidences a marked anisotropy of the Stone-Wales defects that, topologically, are in fact preferably generated and propagated along the diagonal of the graphenic fragments, including carbon nanotubes and graphene nanoribbons. This peculiar edge-effect is shown in this paper having a predominant topological origin, leaving to future experimental investigations the task of verifying the occurrence in nature of wave-like defects similar to the ones proposed here. Graph-theoretical tools used in this paper for the generation and the propagation of the Stone-Wales defects waves are applicable to investigate isomeric modifications of chemical structures with various dimensionality like fullerenes, nanotubes, graphenic layers, schwarzites, zeolites.

  14. Recurrence rates of urinary calculi according to stone composition and morphology

    DEFF Research Database (Denmark)

    Daudon, Michel; Jungers, Paul; Bazin, Dominique

    2018-01-01

    stone event, with these being more frequent in men (44.4%) than in women (38.9%, p acid (62.5 ± 14.9 years), with the average age of first stones of calcium oxalate falling...... in the middle (40.7 ± 14.6 years for calcium oxalate dihydrate, and 48.4 ± 15.1 years for calcium oxalate monohydrate, COM). By composition alone, COM was among the least recurrent of stones, with only 38.0% of COM stones coming from patients who had had a previous episode; however, when the different...

  15. Study of stone composition changes in melamine-related urinary calculi and its clinical significance.

    Science.gov (United States)

    Li, Yuan; Chen, YiRong; Zhang, Wei; Huang, XiaoGang; Li, WenHui; Ru, XiaoRui; Meng, Min; Xi, Xinsheng; Huang, Gang; Shi, BaoGuang; Liu, Gang; Li, WeiHua; Xu, Hui

    2011-08-01

    To investigate the composition changes in melamine-related urinary calculi and their clinical significance. A total of 49 melamine-related urinary calculi were included from 49 children (age 4-82 months, mean 22). The qualitative analysis of stone composition was determined using Fourier transform infrared. The quantitative analysis of the stone computed tomography (CT) attenuation value, stone uric acid level, and stone calcium level were measured using spiral CT, high-performance liquid chromatography, and flame atomic absorption spectrum, respectively. Fourier transform infrared showed that 41 (84%) of the 49 stones contained uric acid and 25 (51%) contained calcium compounds. The data from the qualitative and quantitative analysis were available for 15 stones because of sample consumption in the detection process (Fourier transform infrared, atomic absorption spectrum, and high-performance liquid chromatography). A negative correlation was observed between stone uric acid level and stone calcium level (n = 15, r = -0.629, P = .009). A positive correlation was observed between the stone calcium level and stone CT attenuation value (n = 25, r = 0.855, P = .000). Compared with the ≤1-year-age group and the 1-2-year-age group, the stone calcium level in the >2-year-age group was significantly greater (27.51% ± 12.65% vs 1.60% ± 1.68% or 10.12% ± 8.69%, P = .000 and P = .003, respectively). Compared with the alkalization-alone group, the stone calcium level in the nonalkalization-alone group was significant greater (19.83% ± 7.48% vs 1.25% ± 1.43%, n = 19, P = .000). The stones from children >2 years old were not amenable to medical treatment because they contained greater levels of calcium, which can be demonstrated by the radiologic "positive stone image" or stone CT attenuation value. We believe that surgical invention will be the best choice for such patients if extracorporeal shock wave lithotripsy has failed. Copyright © 2011 Elsevier Inc. All rights

  16. Healing stone ... by infection

    OpenAIRE

    Micallef, Roderick

    2014-01-01

    Roderick Micallef has a long family history within the construction industry. He coupled this passion with a fascination with science when reading for an undergraduate degree in Biology and Chemistry (University of Malta). http://www.um.edu.mt/think/healing-stone-by-infection/

  17. Throwing behavior and mass distribution of stone selection in tufted capuchin monkeys (Cebus apella).

    Science.gov (United States)

    Cleveland, A; Rocca, A R; Wendt, E L; Westergaard, G C

    2003-12-01

    Cannell [Journal of Archaeological Science 29:335-339, 2002] argued that sex-based differences among humans in terms of the mass of chosen throwing stones could be used to infer body mass and patterns of sexual dimorphism in early hominids from Olduvai and Koobi Fora by examining the mass distributions of unaltered stone tools at those sites. We examined this hypothesis in tufted capuchin monkeys using a comparative approach, by investigating the relationships among body mass, sex, stone weight preference, and accuracy in a throwing task. The subject sample consisted of nine monkeys trained to perform an aimed-throwing task in which a food reward could be obtained by throwing a stone into a bucket. We found that 1) the subjects showed a strong mean stone mass preference; 2) the females chose heavier stones than the males, in terms of absolute mean selected stone mass and selected stone mass relative to body mass; 3) subjects threw more accurately when they used stones of preferred mass vs. stones of nonpreferred mass; and 4) overall, the males were more accurate in the throwing task than the females. We conclude that capuchins are highly selective when choosing throwing stones, and that this confers an advantage for throwing accuracy. Our results indicate that the sexually dimorphic pattern in stone mass preference observed among humans does not generalize to Cebus apella. We suggest that researchers examining this pattern in humans in an attempt to explain early hominid patterns of dimorphism and behavior should take into account not only stone weight preference, but also its adaptive advantage. Copyright 2003 Wiley-Liss, Inc.

  18. Building stones from a muddy delta: Native natural stone from The Netherlands

    NARCIS (Netherlands)

    Nijland, T.G.; Dubelaar, C.W.; Tolboom, H.J.; Hees, R.P.J. van

    2006-01-01

    Most of the Netherlands a Quaternary delta, local supplies of natural stone suitable for building are rare. These include: Quaternary bog iron ores used in early medieval times (until c. 1200); erratics, deposited in boulder clay during the Saalian ice age in the northern Netherlands and gravel from

  19. Laparoendoscopic management of concomitant gallbladder stones and common bile duct stones: what is the best technique?

    Science.gov (United States)

    El-Geidie, Ahmed Abdel-Raouf

    2011-08-01

    The intraoperative use of endoscopic retrograde cholangiopancreatography (ERCP) during laparoscopic cholecystectomy (LC) is a safe, single-stage option for the management of concomitant gallstones (GS) and common bile duct stones (CBDS). This study aims to compare between 2 techniques of combined laparoendoscopic management, which are laparoendoscopic Rendez-vous (LC/LERV) technique and standard ERCP after the completion of LC intraoperative endoscopic sphincterotomy (IOES). Patients with GS and suspected CBDS were included. They were divided into 2 groups; LC/LERV and LC/IOES. Both groups were compared for failure of endoscopic sphincterotomy/stone extraction, operative time, conversion rate, mortality/morbidity, and length of hospital stay. Between October 2007 and February 2010, 98 patients with GS and CBDS were eligible for inclusion in the study. They were prospectively randomized into 2 groups; LC/LERV (N=45) and LC/IOES (N=53). There were no differences in preoperative parameters between both groups. There was a significant difference in operative time (shorter for LC/IOES). No difference was noted in success/failure rate, post-ERCP pancreatitis. Both Standard ERCP after the completion of LC and LC/LERV are valid single-session management for CBD stones, but LC-ERCP may be preferred.

  20. Extensive characterizations of bacteria isolated from catheterized urine and stone matrices in patients with nephrolithiasis.

    Science.gov (United States)

    Tavichakorntrakool, Ratree; Prasongwattana, Vitoon; Sungkeeree, Seksit; Saisud, Phitsamai; Sribenjalux, Pipat; Pimratana, Chaowat; Bovornpadungkitti, Sombat; Sriboonlue, Pote; Thongboonkerd, Visith

    2012-11-01

    Urinary tract infections are generally known to be associated with nephrolithiasis, particularly struvite stone, in which the most common microbe found is urea-splitting bacterium, i.e. Proteus mirabilis. However, our observation indicated that it might not be the case of stone formers in Thailand. We therefore extensively characterized microorganisms associated with all types of kidney stones. A total of 100 kidney stone formers (59 males and 41 females) admitted for elective percutaneous nephrolithotomy were recruited and microorganisms isolated from catheterized urine and cortex and nidus of their stones were analyzed. From 100 stone formers recruited, 36 cases had a total of 45 bacterial isolates cultivated from their catheterized urine and/or stone matrices. Among these 36 cases, chemical analysis by Fourier-transformed infrared spectroscopy revealed that 8 had the previously classified 'infection-induced stones', whereas the other 28 cases had the previously classified 'metabolic stones'. Calcium oxalate (in either pure or mixed form) was the most common and found in 64 and 75% of the stone formers with and without bacterial isolates, respectively. Escherichia coli was the most common bacterium (approximately one-third of all bacterial isolates) found in urine and stone matrices (both nidus and periphery). Linear regression analysis showed significant correlation (r = 0.860, P stone matrices. Multidrug resistance was frequently found in these isolated bacteria. Moreover, urea test revealed that only 31% were urea-splitting bacteria, whereas the majority (69%) had negative urea test. Our data indicate that microorganisms are associated with almost all chemical types of kidney stones and urea-splitting bacteria are not the major causative microorganisms found in urine and stone matrices of the stone formers in Thailand. These data may lead to rethinking and a new roadmap for future research regarding the role of microorganisms in kidney stone formation.