Theoretical analysis of the mechanisms of a gender differentiation in the propensity for orthostatic intolerance after spaceflight

<p>Abstract</p> <p>Background</p> <p>A tendency to develop reentry orthostasis after a prolonged exposure to microgravity is a common problem among astronauts. The problem is 5 times more prevalent in female astronauts as compared to their male counterparts. The mechanisms responsible for this gender differentiation are poorly understood despite many detailed and complex investigations directed toward an analysis of the physiologic control systems involved.</p> <p>Methods</p> <p>In this study, a series of computer simulation studies using a mathematical model of cardiovascular functioning were performed to examine the proposed hypothesis that this phenomenon could be explained by basic physical forces acting through the simple common anatomic differences between men and women. In the computer simulations, the circulatory components and hydrostatic gradients of the model were allowed to adapt to the physical constraints of microgravity. After a simulated period of one month, the model was returned to the conditions of earth's gravity and the standard postflight tilt test protocol was performed while the model output depicting the typical vital signs was monitored.</p> <p>Conclusions</p> <p>The analysis demonstrated that a 15% lowering of the longitudinal center of gravity in the anatomic structure of the model was all that was necessary to prevent the physiologic compensatory mechanisms from overcoming the propensity for reentry orthostasis leading to syncope.</p

Fine Scale Analysis of Crossover and Non-Crossover and Detection of Recombination Sequence Motifs in the Honeybee (Apis mellifera)

BACKGROUND: Meiotic exchanges are non-uniformly distributed across the genome of most studied organisms. This uneven distribution suggests that recombination is initiated by specific signals and/or regulations. Some of these signals were recently identified in humans and mice. However, it is unclear whether or not sequence signals are also involved in chromosomal recombination of insects. METHODOLOGY: We analyzed recombination frequencies in the honeybee, in which genome sequencing provided a large amount of SNPs spread over the entire set of chromosomes. As the genome sequences were obtained from a pool of haploid males, which were the progeny of a single queen, an oocyte method (study of recombination on haploid males that develop from unfertilized eggs and hence are the direct reflect of female gametes haplotypes) was developed to detect recombined pairs of SNP sites. Sequences were further compared between recombinant and non-recombinant fragments to detect recombination-specific motifs. CONCLUSIONS: Recombination events between adjacent SNP sites were detected at an average distance of 92 bp and revealed the existence of high rates of recombination events. This study also shows the presence of conversion without crossover (i. e. non-crossover) events, the number of which largely outnumbers that of crossover events. Furthermore the comparison of sequences that have undergone recombination with sequences that have not, led to the discovery of sequence motifs (CGCA, GCCGC, CCGCA), which may correspond to recombination signals

Personalization for unobtrusive service interaction

Increasingly, mobile devices play a key role in the communication between users and the services embedded in their environment. With ever greater number of services added to our surroundings, there is a need to personalize services according to the user needs and environmental context avoiding service behavior from becoming overwhelming. In order to prevent this information overload, we present a method for the development of mobile services that can be personalized in terms of obtrusiveness (the degree in which each service intrudes the user's mind) according to the user needs and preferences. That is, services can be developed to provide their functionality at different obtrusiveness levels depending on the user by minimizing the duplication of efforts. On the one hand, we provide mechanisms for describing the obtrusiveness degree required for a service. On the other hand, we make use of Feature Modeling techniques in order to define the obtrusiveness level adaptation in a declarative manner. An experiment was conducted in order to put in practice the proposal and evaluate the user acceptance for the personalization capabilities provided by our approach. © Springer-Verlag London Limited 2011.This work has been developed with the support of MICINN under the project EVERYWARE TIN2010-18011 and co-financed with ERDF, in the grants program FPU.Gil Pascual, M.; Giner Blasco, P.; Pelechano Ferragud, V. (2012). Personalization for unobtrusive service interaction. Personal and Ubiquitous Computing. 16(5):543-561. https://doi.org/10.1007/s00779-011-0414-0S543561165Abrams M, Phanouriou C, Batongbacal AL, Williams SM, Shuster JE (1999) Uiml: an appliance-independent xml user interface language. In: WWW ’99. Elsevier, North-Holland, pp 1695–1708Ballagas R, Borchers J, Rohs M, Sheridan JG (2006) The smart phone: a ubiquitous input device. IEEE Pervas Comput 5(1):70Balme L, Demeure A, Barralon N, Coutaz J, Calvary G (2004) Cameleon-rt: a software architecture reference model for distributed, migratable, and plastic user interfaces. In: EUSAI, pp 291–302Benavides D, Cortés RA, Trinidad P (2005) Automated reasoning on feature models. In: LNCS, advanced information systems engineering: 17th international conference, CAiSE 2005 3520, pp 491–503Blomquist A, Arvola M (2002) Personas in action: ethnography in an interaction design team. In: Proceedings of NordiCHI ’02. ACM, New York, NY, pp 197–200Bright A, Kay J, Ler D, Ngo K, Niu W, Nuguid A (2005) Adaptively recommending museum tours. In: Nick Ryan Tullio Salmon Cinotti GR (ed) Proceedings of workshop on smart environments and their applications to cultural heritage. Archaeolingua, pp 29–32Brown DM (2010) Communicating design: developing web site documentation for design and planning, 2nd edn. New Riders Press, USACalvary G, Coutaz J, Thevenin D, Limbourg Q, Bouillon L, Vanderdonckt J (2003) A unifying reference framework for multi-target user interfaces. Interact Comput 15(3):289–308Cetina C, Giner P, Fons J, Pelechano V (2009) Autonomic computing through reuse of variability models at runtime: the case of smart homes. Computer 42(10):37–43Chatfield C, Carmichael D, Hexel R, Kay J, Kummerfeld B (2005) Personalisation in intelligent environments: managing the information flow. In: OZCHI ’05. Computer-human interaction special interest group of Australia, pp 1–10Clerckx T, Winters F, Coninx K (2005) Tool support for designing context-sensitive user interfaces using a model-based approach. In: TAMODIA ’05: Proceedings of the 4th international workshop on Task models and diagrams. ACM Press, New York, pp 11–18Czarnecki K, Helsen S, Eisenecker U (2004) Staged configuration using feature models. In: Proceedings of SPLCDuarte C, Carriço L (2006) A conceptual framework for developing adaptive multimodal applications. In: Proceedings of IUI ’06. ACM, New York, pp 132–139Evans (2003) Domain-driven design: tacking complexity In the heart of software. Addison-Wesley Longman Publishing Co., Inc., BostonsFavre JM (2004) Foundations of model (Driven) (Reverse) engineering: models—Episode I: stories of the fidus papyrus and of the solarus. In: Bezivin J, Heckel R (eds) Language engineering for model-driven software development, no. 04101, Dagstuhl seminar proceedings. Dagstuhl, GermanyFischer G (2001) User modeling in human–computer interaction. User Model User-Adap Inter 11(1–2):65–86Gibbs WW (2005) Considerate computing. Scientific American 292(1):54–61Giner P, Cetina C, Fons J, Pelechano V (2010) Developing mobile workflow support in the internet of things. IEEE Pervas Comput 9(2):18–26Giner P, Cetina C, Fons J, Pelechano V (2011) Implicit interaction design for pervasive workflows. Pers Ubiquit Comput 1–10Gulliksen J, Goransson B, Boivie I, Blomkvist S, Persson J, Cajander A (2003) Key principles for user-centred systems design. Behav Inform Technol 22:397–409Hinckley K, Horvitz E (2001) Toward more sensitive mobile phones. In: Proceedings of the UIST ’01. ACM, New York, pp 191–192Ho J, Intille SS (2005) Using context-aware computing to reduce the perceived burden of interruptions from mobile devices. In: Proceedings of CHI ’05. ACM, New York, pp 909–918Horvitz E, Kadie C, Paek T, Hovel D (2003) Models of attention in computing and communication: from principles to applications. Commun ACM 46(3):52–59Ju W, Leifer L (2008) The design of implicit interactions: making interactive systems less obnoxious. Des Issues 24(3):72–84Lewis JR (1995) Ibm computer usability satisfaction questionnaires: psychometric evaluation and instructions for use. Int J Hum-Comput Interact 7(1):57–78Limbourg Q, Vanderdonckt J, Michotte B, Bouillon L, López-Jaquero V (2004) Usixml: a language supporting multi-path development of user interfaces. In: EHCI/DS-VIS, pp 200–220Mao JY, Vredenburg K, Smith PW, Carey T (2001) User-centered design methods in practice: a survey of the state of the art. In: CASCON ’01. IBM Press, New York, p 12McCrickard DS, Chewar CM (2003) Attuning notification design to user goals and attention costs. Commun ACM 46:67–72Mori G, Paternò F, Santoro C (2002) Ctte: support for developing and analyzing task models for interactive system design. IEEE Trans Softw Eng 28(8):797–813Mori G, Paternò F, Santoro C (2004) Design and development of multidevice user interfaces through multiple logical descriptions. IEEE Trans Softw Eng 30(8):507–520Myers B, Hudson SE, Pausch R (2000) Past, present, and future of user interface software tools. ACM Trans Comput-Hum Interact 7(1):3–28OMG (2006) Business process modeling notation (BPMN) specification. OMG Final Adopted SpecificationPaternò F, Santoro C (2003) A unified method for designing interactive systems adaptable to mobile and stationary platforms. Interact Comput 15(3):349–366Puerta A, Eisenstein J (2002) Ximl: a common representation for interaction data. In: Proceedings of IUI ’02. ACM, New York, pp 214–215Ramchurn SD, Deitch B, Thompson MK, Roure DCD, Jennings NR, Luck M (2004) Minimising intrusiveness in pervasive computing environments using multi-agent negotiation. In: First international conference on mobile and ubiquitous systems, pp 364–372Rumbaugh J, Jacobson I, Booch G (1998) The unified modeling language reference manual. Addison-Wesley, LondonSchobbens PY, Heymans P, Trigaux JC, Bontemps Y (2007) Generic semantics of feature diagrams. Comput Networks 51(2):456–479Serral E, Pérez F, Valderas P, Pelechano V (2010) An end-user tool for adapting smart environment automation to user behaviour at runtime. In: Proceedings of UCAmI ’10Streefkerk JW, van Esch-Bussemakers MP, Neerincx MA (2006) Designing personal attentive user interfaces in the mobile public safety domain. Comput Hum Behav 22:749–770Tedre M (2008) What should be automated? Interactions 15(5):47–49Unger R, Chandler C (2009) A project guide to UX design: for user experience designers in the field or in the making. New Riders Publishing, Thousand OaksVan den Bergh J, Coninx K. Using uml 2.0 and profiles for modelling context-sensitive user interfaces. In: Proceedings of the MDDAUI2005 CEUR workshopVastenburg MH, Keyson DV, de Ridder H (2008) Considerate home notification systems: a field study of acceptability of notifications in the home. Pers Ubiquit Comput 12(8):555–566Vertegaal R (2003) Attentive user interfaces. Commun ACM 46(3):30–33Weiser M, Brown JS (1997) The coming age of calm technology, pp 75–85Weld DS, Anderson C, Domingos P, Etzioni O, Gajos K, Lau T, Wolf S (2003) Automatically personalizing user interfaces. In: IJCAI ’03, pp 1613–161

Freeze-thaw treatment effects on the dynamic mechanical properties of articular cartilage

BACKGROUND: As a relatively non-regenerative tissue, articular cartilage has been targeted for cryopreservation as a method of mitigating a lack of donor tissue availability for transplant surgeries. In addition, subzero storage of articular cartilage has long been used in biomedical studies using various storage temperatures. The current investigation studies the potential for freeze-thaw to affect the mechanical properties of articular cartilage through direct comparison of various subzero storage temperatures. METHODS: Both subzero storage temperature as well as freezing rate were compared using control samples (4°C) and samples stored at either -20°C or -80°C as well as samples first snap frozen in liquid nitrogen (-196°C) prior to storage at -80°C. All samples were thawed at 37.5°C to testing temperature (22°C). Complex stiffness and hysteresis characterized load resistance and damping properties using a non-destructive, low force magnitude, dynamic indentation protocol spanning a broad loading rate range to identify the dynamic viscoelastic properties of cartilage. RESULTS: Stiffness levels remained unchanged with exposure to the various subzero temperatures. Hysteresis increased in samples snap frozen at -196°C and stored at -80°C, though remained unchanged with exposure to the other storage temperatures. CONCLUSIONS: Mechanical changes shown are likely due to ice lens creation, where frost heave effects may have caused collagen damage. That storage to -20°C and -80°C did not alter the mechanical properties of articular cartilage shows that when combined with a rapid thawing protocol to 37.5°C, the tissue may successfully be stored at subzero temperatures

Octreotide treatment of patients with hepatocellular carcinoma - a retrospective single centre controlled study

<p>Abstract</p> <p>Background</p> <p>Studies of treatment with octreotide of patients with hepatocellular carcinoma (HCC) gave conflicting results. We analyzed retrospectively the survival of our patients treated with octreotide monotherapy and compared it to stage-matched patients who received either TACE, multimodal therapy or palliative care.</p> <p>Methods</p> <p>95 patients seen at the department of Gastroenterology and Hepatology, Medical University of Vienna with HCC in BCLC stage A or B, who received either TACE, multimodal therapy, long-acting octreotide or palliative care were reviewed for this retrospective study.</p> <p>Results</p> <p>Survival rates of patients with BCLC stage B and any "active" treatment (long-acting octreotide, TACE or multimodal therapy) were significantly higher (22.4, 22.0, 35.5 months) compared to patients who received palliative care only (2.9 months). Survival rates of patients with BCLC stage A and "active" treatment (31.4, 37.3, 40.2 months) compared to patients who received only palliative care (15.1 months) did not show statistically significant differences. Octreotide monotherapy showed a similar outcome compared to patients who received TACE or multimodal therapy.</p> <p>Conclusion</p> <p>Survival under octreotide treatment was not different compared to TACE or multimodal therapy and might be a therapeutic option for patients with HCC.</p

Eating Disorder Behaviors Are Increasing: Findings from Two Sequential Community Surveys in South Australia

Background: evidence for an increase in the prevalence of eating disorders is inconsistent. Our aim was to determine change in the population point prevalence of eating disorder behaviors over a 10-year period. \ud \ud Methodology/Principal Findings: eating disorder behaviors were assessed in consecutive general population surveys of men and women conducted in 1995 (n = 3001, 72% respondents) and 2005 (n = 3047, 63.1% respondents). Participants were randomly sampled from households in rural and metropolitan South Australia. There was a significant (all p,0.01) and over two-fold increase in the prevalence of binge eating, purging (self-induced vomiting and/or laxative or diuretic misuse) and strict dieting or fasting for weight or shape control among both genders. The most common diagnosis in 2005 was either binge eating disorder or other ‘‘eating\ud disorders not otherwise specified’’ (EDNOS; n = 119, 4.2%). \ud \ud Conclusions/Significance: in this population sample the point prevalence of eating disorder behaviors increased over the past decade. Cases of anorexia nervosa and bulimia nervosa, as currently defined, remain uncommon

Stationary Black Holes: Uniqueness and Beyond

The spectrum of known black-hole solutions to the stationary Einstein equations has been steadily increasing, sometimes in unexpected ways. In particular, it has turned out that not all black-hole-equilibrium configurations are characterized by their mass, angular momentum and global charges. Moreover, the high degree of symmetry displayed by vacuum and electro-vacuum black-hole spacetimes ceases to exist in self-gravitating non-linear field theories. This text aims to review some developments in the subject and to discuss them in light of the uniqueness theorem for the Einstein-Maxwell system.Comment: Major update of the original version by Markus Heusler from 1998. Piotr T. Chru\'sciel and Jo\~ao Lopes Costa succeeded to this review's authorship. Significantly restructured and updated all sections; changes are too numerous to be usefully described here. The number of references increased from 186 to 32

Is PTEN loss associated with clinical outcome measures in human prostate cancer?

Inactivating PTEN mutations are commonly found in prostate cancer, resulting in an increased activation of Akt. In this study, we investigate the role of PTEN deletion and protein expression in the development of hormone-refractory prostate cancer using matched hormone-sensitive and hormone-refractory tumours. Fluorescent in situ hybridisation and immunohistochemistry was carried out to investigate PTEN gene deletion and PTEN protein expression in the transition from hormone-sensitive to hormone-refractory prostate cancer utilising 68 matched hormone sensitive and hormone-refractory tumour pairs (one before and one after hormone relapse). Heterogeneous PTEN gene deletion was observed in 23% of hormone sensitive tumours. This increased significantly to 52% in hormone-refractory tumours (P=0.044). PTEN protein expression was observed in the membrane, cytoplasm and the nucleus. In hormone sensitive tumours, low levels of cytoplasmic PTEN was independently associated with shorter time to relapse compared to high levels of PTEN (P=0.028, hazard ratio 0.51 (95%CI 0.27–0.93). Loss of PTEN expression in the nucleus of hormone sensitive tumours was independently associated with disease-specific survival (P=0.031, hazard ratio 0.52, 95%CI 0.29–0.95). The results from this study demonstrate a role for both cytoplasmic and nuclear PTEN in progression of prostate cancer to the hormone-refractory state

Parameter selection for and implementation of a web-based decision-support tool to predict extubation outcome in premature infants

BACKGROUND: Approximately 30% of intubated preterm infants with respiratory distress syndrome (RDS) will fail attempted extubation, requiring reintubation and mechanical ventilation. Although ventilator technology and monitoring of premature infants have improved over time, optimal extubation remains challenging. Furthermore, extubation decisions for premature infants require complex informational processing, techniques implicitly learned through clinical practice. Computer-aided decision-support tools would benefit inexperienced clinicians, especially during peak neonatal intensive care unit (NICU) census. METHODS: A five-step procedure was developed to identify predictive variables. Clinical expert (CE) thought processes comprised one model. Variables from that model were used to develop two mathematical models for the decision-support tool: an artificial neural network (ANN) and a multivariate logistic regression model (MLR). The ranking of the variables in the three models was compared using the Wilcoxon Signed Rank Test. The best performing model was used in a web-based decision-support tool with a user interface implemented in Hypertext Markup Language (HTML) and the mathematical model employing the ANN. RESULTS: CEs identified 51 potentially predictive variables for extubation decisions for an infant on mechanical ventilation. Comparisons of the three models showed a significant difference between the ANN and the CE (p = 0.0006). Of the original 51 potentially predictive variables, the 13 most predictive variables were used to develop an ANN as a web-based decision-tool. The ANN processes user-provided data and returns the prediction 0–1 score and a novelty index. The user then selects the most appropriate threshold for categorizing the prediction as a success or failure. Furthermore, the novelty index, indicating the similarity of the test case to the training case, allows the user to assess the confidence level of the prediction with regard to how much the new data differ from the data originally used for the development of the prediction tool. CONCLUSION: State-of-the-art, machine-learning methods can be employed for the development of sophisticated tools to aid clinicians' decisions. We identified numerous variables considered relevant for extubation decisions for mechanically ventilated premature infants with RDS. We then developed a web-based decision-support tool for clinicians which can be made widely available and potentially improve patient care world wide