Hardness of Exact Distance Queries in Sparse Graphs Through Hub Labeling

A distance labeling scheme is an assignment of bit-labels to the vertices of an undirected, unweighted graph such that the distance between any pair of vertices can be decoded solely from their labels. An important class of distance labeling schemes is that of hub labelings, where a node $v \in G$ stores its distance to the so-called hubs $S_v \subseteq V$, chosen so that for any $u,v \in V$ there is $w \in S_u \cap S_v$ belonging to some shortest $uv$ path. Notice that for most existing graph classes, the best distance labelling constructions existing use at some point a hub labeling scheme at least as a key building block. Our interest lies in hub labelings of sparse graphs, i.e., those with $|E(G)| = O(n)$, for which we show a lowerbound of $\frac{n}{2^{O(\sqrt{\log n})}}$ for the average size of the hubsets. Additionally, we show a hub-labeling construction for sparse graphs of average size $O(\frac{n}{RS(n)^{c}})$ for some $0 < c < 1$, where $RS(n)$ is the so-called Ruzsa-Szemer{\'e}di function, linked to structure of induced matchings in dense graphs. This implies that further improving the lower bound on hub labeling size to $\frac{n}{2^{(\log n)^{o(1)}}}$ would require a breakthrough in the study of lower bounds on $RS(n)$, which have resisted substantial improvement in the last 70 years. For general distance labeling of sparse graphs, we show a lowerbound of $\frac{1}{2^{O(\sqrt{\log n})}} SumIndex(n)$, where $SumIndex(n)$ is the communication complexity of the Sum-Index problem over $Z_n$. Our results suggest that the best achievable hub-label size and distance-label size in sparse graphs may be $\Theta(\frac{n}{2^{(\log n)^c}})$ for some $0<c < 1$

The spectrum of phenotypes associated with mutations in steroidogenic factor 1 (SF-1, NR5A1, Ad4BP) includes severe penoscrotal hypospadias in 46,XY males without adrenal insufficiency

OBJECTIVE. Hypospadias is a frequent congenital anomaly but in most cases an underlying cause is not found. Steroidogenic factor 1 (SF-1, NR5A1, Ad4BP) is a key regulator of human sex development and an increasing number of SF-1 (NR5A1) mutations are reported in 46,XY disorders of sex development (DSD). We hypothesized that NR5A1 mutations could be identified in boys with hypospadias. DESIGN AND METHODS. Mutational analysis of NR5A1 in 60 individuals with varying degrees of hypospadias from the German DSD network. RESULTS. Heterozygous NR5A1 mutations were found in three out of 60 cases. These three individuals represented the most severe end of the spectrum studied as they presented with penoscrotal hypospadias, variable androgenization of the phallus and undescended testes (three out of 20 cases (15%) with this phenotype). Testosterone was low in all three patients and inhibin B/anti-Müllerian hormone (AMH) were low in two patients. Two patients had a clear male gender assignment. Gender re-assignment to male occurred in the third case. Two patients harbored heterozygous nonsense mutations (p.Q107X/WT, p.E11X/WT). One patient had a heterozygous splice site mutation in intron 2 (c.103-3A/WT) predicted to disrupt the main DNA-binding motif. Functional studies of the nonsense mutants showed impaired transcriptional activation of an SF-1-responsive promoter (Cyp11a). To date, adrenal insufficiency has not occurred in any of the patients. CONCLUSIONS. SF-1 (NR5A1) mutations should be considered in 46,XY individuals with severe (penoscrotal) hypospadias, especially if undescended testes, low testosterone, or low inhibin B/AMH levels are present. SF-1 mutations in milder forms of idiopathic hypospadias are unlikely to be common

Career Guidance Shortages in Indonesian Vocational High School

Career guidance as an integral part of national education system plays a prominent role in vocational education to facilitate the students in achieving their self-reliance. The discussion on their relationship raises stimulating evidence of weaknesses in its practice in Indonesian vocational high school. This article highlights the substance of career guidance shortages and the implications from its tradition. Thorough analysis shows that career guidance should be simultaneous with vocational education programs to prepare graduates who are standing by to employ. The shortages of career guidance in vocational high school means a small portion, non-stipulated of achievement standards, and hardly congenial to vocational education characteristics. The revitalization act, labor market and skills trends, and career pathways affiliate to the necessity of particular career guidance in vocational high school. It should be noted that specificity of career guidance in vocational high school is aimed to strengthen the employability skills development. &nbsp; &nbsp; Keywords: career guidance, vocational education, employability skill

Rethinking citizen participation in scientific and technical issues : a study within the Spanish local government

La creciente complejidad de las cuestiones tecnocientíficas ha supuesto un reto para la toma de decisiones en nuestras democracias. Así, durante las dos últimas décadas hemos asistido a un auge de procesos participativos que guardan la promesa de democratizar estas cuestiones a través de la inclusión de los ciudadanos en la toma de decisiones. Este trabajo pretende estudiar los discursos y prácticas de los organizadores de procesos participativos en España para analizar los límites de estas propuestas. Para ello, se ha realizado un estudio de ocho casos mediante material públicamente disponible sobre los mismos y un conjunto de entrevistas a los responsables de estos procesos. El análisis de los datos recogidos revela que, aunque la participación de personas legas se considera una contribución positiva, la propia configuración de la participación -basada en una problemática división entre expertos y no expertos- acaba limitando la ambición de democratizar la toma de decisiones. A partir de estas constataciones, y aprovechando algunas enseñanzas del campo del activismo, el trabajo propone una 'participación in the wild', que permita repensar la disposición de etapas y ritmos de los procesos participativos, y así desdibujar las asimetrías que constituyen estos dispositivos. Un trabajo que pretende contribuir al ensamblaje de elementos de la teoría política y los estudios de ciencia y tecnología, tendiendo un puente entre dos campos que pueden hacer importantes aportaciones para lograr formas más democráticas de concebir la toma de decisiones sobre ciencia y tecnología en sociedad.The growing complexity of technoscientific issues has posed a challenge to decision-making in our democracies. Over the last two decades, we have thus witnessed a rise in the participatory processes that promise to democratize these issues by including citizens in decision-making. This paper aims to study the discourses and practices of the organizers of participatory processes in Spain to analyze these proposals' limits. In order to accomplish this objective, we conducted eight case studies by interviewing the individuals responsible for these processes and examining publicly available materials related to them. The analysis of the collected data reveals that, although the participation of laypeople is considered a positive contribution, the very configuration of participation-based on a problematic division between experts and non-experts-ends up limiting the ambition of democratizing decision-making. Based on these findings and drawing on lessons from the field of activism, the paper proposes a 'participation in the wild', which would allow rethinking the disposition of the stages and rhythms of participatory processes, and thereby blur the asymmetries that constitute these devices. This work, therefore, aims to contribute to the assembly of elements of political theory and science and technology studies, as well as bridging the gap between two fields that can make important contributions to achieve more democratic ways of conceiving decision-making concerning science and technology in society

Shortest Path Computation with No Information Leakage

Shortest path computation is one of the most common queries in location-based services (LBSs). Although particularly useful, such queries raise serious privacy concerns. Exposing to a (potentially untrusted) LBS the client's position and her destination may reveal personal information, such as social habits, health condition, shopping preferences, lifestyle choices, etc. The only existing method for privacy-preserving shortest path computation follows the obfuscation paradigm; it prevents the LBS from inferring the source and destination of the query with a probability higher than a threshold. This implies, however, that the LBS still deduces some information (albeit not exact) about the client's location and her destination. In this paper we aim at strong privacy, where the adversary learns nothing about the shortest path query. We achieve this via established private information retrieval techniques, which we treat as black-box building blocks. Experiments on real, large-scale road networks assess the practicality of our schemes.Comment: VLDB201

Potential of the TROPOspheric Monitoring Instrument (TROPOMI) onboard the Sentinel-5 Precursor for the monitoring of terrestrial chlorophyll fluorescence

Global monitoring of sun-induced chlorophyll fluorescence (SIF) is improving our knowledge about the photosynthetic functioning of terrestrial ecosystems. The feasibility of SIF retrievals from spaceborne atmospheric spectrometers has been demonstrated by a number of studies in the last years. In this work, we investigate the potential of the upcoming TROPOspheric Monitoring Instrument (TROPOMI) onboard the Sentinel-5 Precursor satellite mission for SIF retrieval. TROPOMI will sample the 675–775 nm spectral window with a spectral resolution of 0.5 nm and a pixel size of 7 km × 7 km. We use an extensive set of simulated TROPOMI data in order to assess the uncertainty of single SIF retrievals and subsequent spatio-temporal composites. Our results illustrate the enormous improvement in SIF monitoring achievable with TROPOMI with respect to comparable spectrometers currently in-flight, such as the Global Ozone Monitoring Experiment-2 (GOME-2) instrument. We find that TROPOMI can reduce global uncertainties in SIF mapping by more than a factor of 2 with respect to GOME-2, which comes together with an approximately 5-fold improvement in spatial sampling. Finally, we discuss the potential of TROPOMI to map other important vegetation parameters at a global scale with moderate spatial resolution and short revisit time. Those include leaf photosynthetic pigments and proxies for canopy structure, which will complement SIF retrievals for a self-contained description of vegetation condition and functioning

Estudio macroscópico, radiológico y histológico de una fractura tibial de Myotragus balearicus

X Congreso Nacional de Paleopatología. Univesidad Autónoma de Madrid, septiembre de 200