Lyme Borreliosis During Pregnancy

One of the authors (AL) presented a poster on 34 pregnancies of maternal Lyme borreliosis (Lb) in 1995. It was striking that untreated Lb associated with higher probability of adverse outcome but the number of patients were small and the statistical power was low. We have recently published a paper on 95 maternal Lb and the outcome of their pregnancies. Since the closure of the database for that manuscript the number of the pregnant women with Borrelia infection observed in our Centre increased to 124, and the statistical analysis strengthened our previous doubtful observations and reached significant results in important aspects by now. This series is the largest study to date on this topic. Treatment was administered parenterally to 87 (70%) women and orally to 25 (20.0%). Infection remained untreated in 12 (10%) pregnancies. Adverse outcomes were seen in 7/87 (8%), 9/25 (36%), 8/12 (67%), of the parenterally, orally treated and untreated women, respectively. In comparison to patients treated with antibiotics, untreated women had a significantly higher risk of adverse pregnancy outcomes (OR: 11.62, p<0.001). Mothers treated orally comparing to iv. treatment had an increased chance (OR: 6.28) to have an adverse outcome (p=0.001). In the adverse pregnancy outcome, the most impressive difference was between the untreated and parenterally treated women (OR: 21.44, p<0.001). The probability of adverse outcome increased by the exposition time (from the first maternal symptom to the treatment or delivery). When the exposition time has reached four months, the probability of adverse outcome increased by 33%. We had no chance to examine the bacterial invasion of the foetus. Loss of the pregnancy (N=9), small for gestational age or preterm birth (N=7) were the most prevalent adverse outcomes in our series. The other complications were heterogeneous. Our results indicate that untreated or orally treated maternal Borrelia burgdorferi s.l. infection is associated with adverse outcomes. 'Congenital Lyme disease' similar to the Hutchinson's triad in syphilis is unlikely.
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A few remarks on "On certain Vandermonde determinants whose variables separate"

In the recent paper \u201cOn certain Vandermonde determinants whose variables separate\u201d [Linear Algebra and its Applications 449 (2014) pp. 17\u201327], there was established a factorized formula for some bivariate Vandermonde determinants (associated to almost square grids) whose basis functions are formed by Hadamard products of some univariate polynomials. That formula was crucial for proving a conjecture on the Vandermonde determinant associated to Padua-like points. In this note we show that the same formula holds when those polynomials are replaced by arbitrary functions and we extend this formula to general rectangular grids. We also show that the Vandermonde determinants associated to Padua-like points are nonvanishing

The Entrepreneurial Adjustment Process in Disequilibrium: Entry and Exit when Markets Under and Over Shoot

The main contribution of entrepreneurship theory to economics is to provide an account of market performance in disequilibrium but little empirical research has examined firm entry and exit in this context. We redress this by modelling the interrelationship between firm entry and exit in disequilibrium. Introducing a new methodology we investigate whether this interrelationship differs between market 'undershooting' (the actual number of firms is below the equilibrium number) and 'overshooting' (vice versa). We find that equilibrium-restoring mechanisms are faster in over than in undershoots. The results imply that in undershoots a lack of competition between incumbent firms contributes to restoration of equilibrium (creating room for new-firm entry) while in overshoots competition induced by new firms (in particular strong displacement) helps restore equilibrium.entry, exit, equilibrium, industrial organization, undershooting, overshooting

Quantification of growth hormone in serum by isotope dilution mass spectrometry

Inter-assay variation of antibody based routine tests is hampering comparability of measurement results for growth hormone (GH) between different laboratories and decision making in clinical practice. Here it is demonstrated, that quantification of GH by isotope dilution mass spectrometry (IDMS) constitutes a way to precise and reliable results which can be referred to in evaluation of performance of commercial test kits. With the IDMS method developed, tryptic cleavage products YSFLQNPQTSLCFSESIPTPSNR (T6) and LEDGSPR (T12) of GH are quantified by LC/MS-MS using the isotopically labeled forms of the peptides as internal standards. The GH cleavage fragments are obtained by whole-serum tryptic proteolysis and then extracted from the resulting mixture by semi-preparative reversed phase liquid chromatography followed by strong cation-exchange chromatography. Method validation basing on recovery of recombinant 22 kDa GH spiked to blank serum in defined amounts covering the intended concentration range (3-30 µg/L) would yield mean recoveries of 101.6% (100.7%), standard deviations of 2.5% (2.4%) and combined uncertainties (_u~c~_) of 3.0% (2.5%) if quantifying T6 (T12) as GH derived fragments, while the LOQ were 1.7 µg/L (2.7 µg/L). Potential to acquisition of reference values is exemplified by application to serum materials used in a recent quality assessment exercise for routine laboratories

The Evolution of Altruism in Spatially Structured Populations

The evolution of altruism in humans is still an unresolved puzzle. Helping other individuals is often kinship-based or reciprocal. Several examples show, however, that altruism goes beyond kinship and reciprocity and people are willing to support unrelated others even when this is at a cost and they receive nothing in exchange. Here we examine the evolution of this "pure" altruism with a focus on altruistic teaching. Teaching is modeled as a knowledge transfer which enhances the survival chances of the recipient, but reduces the reproductive efficiency of the provider. In an agent-based simulation we compare evolutionary success of genotypes that have willingness to teach with those who do not in two different scenarios: random matching of individuals and spatially structured populations. We show that if teaching ability is combined with an ability to learn and individuals encounter each other on a spatial proximity basis, altruistic teaching will attain evolutionary success in the population. Settlement of the population and accumulation of knowledge are emerging side-products of the evolution of altruism. In addition, in large populations our simple model also produces a counterintuitive result that increasing the value of knowledge keeps fewer altruists alive.Altruism, Teaching, Knowledge Transfer, Spatially Structured Social Dilemmas

Propuesta did?ctica para la construcci?n del concepto de variable como n?mero general basada en el modelo 3UV

156 p. Recurso Electr?nicoEn este proyecto se presentan algunos aspectos fundamentales en los procesos de ense?anza-aprendizaje del concepto de la variable como n?mero general en estudiantes pertenecientes a cinco grados diferentes de ense?anza media del instituto t?cnico Benjam?n Herrera de la ciudad de Ibagu?, teniendo como referentes principales el modelo 3UV (3 Usos de la Variable) Trigueros y Ursini, (2003); Ursini, et al., (2005) y el aprendizaje instrumental y relacional planteado por (Skemp, 1978). Para lo cual se han realizado una secuencia de actividades encaminadas a estos educandos por medio de una metodolog?a apropiada, de tal manera que les permita apropiarse del concepto en distintas facetas, interpretativa, aplicativa, anal?tica, y reflexiva que conlleve a un aprendizaje con comprensi?n y significado; no simplemente reducido a la aplicaci?n de reglas o algoritmos sin sentido. En este proyecto se hace una invitaci?n a la reflexi?n sobre c?mo se est? ense?ando las matem?ticas en nuestro contexto colombiano, sobre la importancia de generar un desarrollo del pensamiento Variacional desde edades tempranas, para fortalecer el paso de la aritm?tica al algebra; en cuanto a esto, es muy importante integrar al curr?culo actividades que pensadas desde lo aritm?tico y geom?trico potencialicen el razonamiento algebraico. Palabras claves: patr?n, ?lgebra, generalidad, unidad did?ctica, variable, modelo 3UV.In this Project are presented some fundamental aspects in the teaching ? learning process from the concept of the variable as a general number in students belonging to five different middle school grades from the Technical Institute Benjam?n Herrera from the city of Ibagu?, taking as principal referents the Model 3UV (3 Uses of the Variable) Trigueros and Ursini, (2003); Ursini, et al., (2005) and the instrumental and relational learning proposed by (Skemp, 1978). For which it has been executed a sequence of activities directed to these students by means of an appropriate methodology, in such a way that allows them to appropriate the concept in different facets, interpretative, applicative, analytical and reflective that lead to a learning with comprehension and meaning; not simply reduced to the application of rules or algorithms with no sense. In this project is made an invitation to the reflection on how mathematics is being taught in our Colombian context, about the importance of generate a development of variational thinking since early ages, to strengthen the passage from arithmetic to algebra; in terms of this, is very important to integrate into the curriculum, activities that thought from the arithmetic and geometric, potentiate the algebraic reasoning. Key words: pattern, algebra, generality, didactic unit, variable, Model 3UV

Assessing Mineral Resource Scarcity in a Circular Economy Context

Due to humanity’s dependence on metal resources there are growing concerns regarding impacts related to their potential scarcity, both for current and future generations. The vision of a more circular economy suggests that extending the functional use of metals through measures aiming for resource-efficiency (RE) such as increasing technical lifetime, repairing and recycling could reduce mineral resource scarcity. However, evidence of this is limited. In addition, there is limited understanding regarding on what principles metals can be prioritized when assessing mineral resource scarcity. The aim of this thesis is to provide knowledge on mineral resource scarcity impacts of RE measures applied to metal-diverse products and on which conditions they depend. This is achieved by: 1) studying RE measures from a life cycle perspective; 2) comparing principles of prioritization between metals on which mineral resource scarcity impacts are assessed and 3) analysing how such principles (of prioritization) can affect conclusions regarding RE measures applied to metal-diverse products. The research is conducted through case studies, syntheses of literature and method development within the methodologies of life cycle assessment, material flow analysis and criticality assessment. \ua0Results indicate that effects of RE measures depend on a number of product characteristics and real-world conditions. RE measures can both increase and decrease mineral resource scarcity impacts compared to business as usual and effects vary greatly between metals. RE measures based on use extension e.g. reuse of laptops, repair of smartphones, and increasing technical lifetimes of LED lighting, have been indicated to reduce impacts through two principal features: use extension, and, increased functional recycling. However, there are risks of increasing mineral resource scarcity impacts if RE measures require additional metal use, product use extensions are short and if functional recycling is lacking. For example, repair of smartphones risks to increase the use of metals in commonly replaced components such as screens. Because of the varying effects on different metals, implementation of RE measures requires prioritizing some metals over others. The principles of prioritization give diverging results, and, are sometimes unclear and methodologically inconsistent. The thesis clarifies how they relate to concepts such as depletion, criticality, rarity and scarcity. Further it suggests that, although mineral resources are fundamentally stock resources, they can pose stock, fund and flow problems. Distinguishing between these different problems in distinct methodologies is conducive to purposive and complementary assessment by resolving methodological inconsistencies and providing accurate terminology. In the long term, scarcity is most purposively addressed by focusing on depletion of ecospheric stocks. Accordingly, the Crustal Scarcity Indicator is proposed to assess potential long term scarcity in life cycle assessment, alongside other environmental impacts. In the near term, potential scarcity for nations, industries and companies, as commonly assessed in criticality assessment, is most purposively addressed by focusing on technospheric circumstances, such as geopolitics, which can disrupt technospheric resource flows. In medium term, secondary resources in technospheric funds could be relevant, especially, with the advent of a more circular economy. Altogether, it is recommended that implementation of RE measures to metal-diverse products are based on analysis of product characteristics and real-world conditions and that effects of RE measures are assessed by methodologies which distinguish between mineral resource flows, funds and stocks so that well-informed prioritizations between metals can be made

Momentum exchange between light and nanostructured matter

An object\u27s translational and rotational motion is associated with linear and angular momenta. When multiple objects interact the exchange of momentum dictates the new system\u27s motion. Since light, despite being massless, carries both linear and angular momentum it too can partake in this momentum exchange and mechanically affect matter in tangible ways. Due to conservation of momentum, any such exchange must be reciprocal, and the light therefore acquires an opposing momentum component. Hence, light and matter are inextricably connected and one can be manipulated to induce interesting effects to the other. Naturally, any such effect is facilitated by having strongly enhanced light-matter interaction, which for visible light is something that is obtained when nanostructured matter supports optical resonances. This thesis explores this reciprocal relationship and how nanostructured matter can be utilised to augment these phenomena.Once focused by a strong lens, light can form optical tweezers which through optical forces and torques can confine and manipulate small particles in space. Metallic nanorods trapped in two dimensions against a cover glass can receive enough angular momentum from circularly polarised light to rotate with frequencies of several tens of kilohertz. In the first paper of this thesis, the photothermal effects associated with such optical rotations are studied to observe elevated thermal environments and morphological changes to the nanorod. Moreover, to elucidate upon the interactions between the trapped particle and the nearby glass surface, in the thesis\u27 second paper a study is conducted to quantify the separation distance between the two under different trapping conditions. The particle is found to be confined ~30-90 nm away from the surface.The momentum exchange from a single nanoparticle to a light beam is negligible. However, by tailoring the response of an array of nanoparticles, phase-gradient metasurfaces can be constructed that collectively and controllably alter the incoming light\u27s momentum in a macroscopically significant way, potentially enabling a paradigm shift to flat optical components. In the thesis\u27 third paper, a novel fabrication technique to build such metasurfaces in a patternable polymer resist is investigated. The technique is shown to produce efficient, large-scale, potentially flexible, substrate-independent flat optical devices with reduced fabricational complexity, required time, and cost.At present, optical metasurfaces are commonly viewed as stationary objects that manipulate light just like common optical components, but do not themselves react to the light\u27s changed momentum. In the last paper of this thesis, it is realised that this is an overlooked potential source of optical force and torque. By incorporating a beam-steering metasurface into a microparticle, a new type of nanoscopic robot – a metavehicle – is invented. Its propulsion and steering are based on metasurface-induced optical momentum transfer and the metavehicle is shown to be driven in complex shapes even while transporting microscopic cargo