160 research outputs found
Size reduction of complex networks preserving modularity
The ubiquity of modular structure in real-world complex networks is being the
focus of attention in many trials to understand the interplay between network
topology and functionality. The best approaches to the identification of
modular structure are based on the optimization of a quality function known as
modularity. However this optimization is a hard task provided that the
computational complexity of the problem is in the NP-hard class. Here we
propose an exact method for reducing the size of weighted (directed and
undirected) complex networks while maintaining invariant its modularity. This
size reduction allows the heuristic algorithms that optimize modularity for a
better exploration of the modularity landscape. We compare the modularity
obtained in several real complex-networks by using the Extremal Optimization
algorithm, before and after the size reduction, showing the improvement
obtained. We speculate that the proposed analytical size reduction could be
extended to an exact coarse graining of the network in the scope of real-space
renormalization.Comment: 14 pages, 2 figure
Data Integration for Open Data on the Web
In this lecture we will discuss and introduce challenges of
integrating openly available Web data and how to solve them. Firstly,
while we will address this topic from the viewpoint of Semantic Web
research, not all data is readily available as RDF or Linked Data, so
we will give an introduction to different data formats prevalent on the
Web, namely, standard formats for publishing and exchanging tabular,
tree-shaped, and graph data. Secondly, not all Open Data is really completely
open, so we will discuss and address issues around licences, terms
of usage associated with Open Data, as well as documentation of data
provenance. Thirdly, we will discuss issues connected with (meta-)data
quality issues associated with Open Data on the Web and how Semantic
Web techniques and vocabularies can be used to describe and remedy
them. Fourth, we will address issues about searchability and integration
of Open Data and discuss in how far semantic search can help to overcome
these. We close with briefly summarizing further issues not covered
explicitly herein, such as multi-linguality, temporal aspects (archiving,
evolution, temporal querying), as well as how/whether OWL and RDFS
reasoning on top of integrated open data could be help
Análisis de la diversidad bacteriana ruminal en cabras criollas durante la transición de una dieta forrajera a una dieta concentrada
En los sistemas de alimentación
intensivos, los rumiantes suelen someterse
a un período de adaptación cuando
se incorpora en su alimentación un elevado
contenido de granos de cereales. Los cambios
microbianos durante esta fase de adaptación
han sido ampliamente reportados utilizando técnicas
de cultivo que permiten la caracterización de sólo unas pocas
especies bacterianas ruminales, dado el carácter anaeróbico
estricto de las bacterias. Los recientes avances en técnicas moleculares
permiten el análisis de tales bacterias sin la necesidad
de cultivarlas, identificando de esta manera muchas bacterias
funcionales y desconocidas como nuevos objetivos de investigación.
Su objetivos es caracterizar los cambios bacterianos ocurridos durante
la transición abrupta desde una dieta forrajera a una dieta
con elevado contenido energético en el rumen de cabras criollas,
mediante qPC
Cambios en la comunidad bacteriana ruminal de cabras criollas durante el timpanismo espumoso
Los recientes avances en técnicas de biología molecular permiten el análisis
de las bacterias ruminales sin la necesidad de cultivarlas, identificando de
esta manera bacterias funcionales, no cultivadas, como nuevos objetivos de
investigación básica y aplicada. Existe un creciente interés en comprender
los mecanismos a partir de los cuales las poblaciones bacterianas muestran
respuestas frente a diferentes estímulos ambientales y/o patologías. Las técnicas
de la Reacción en Cadena de la Polimerasa asociada a Electroforesis
en Gel Gradiente Desnaturalizante (PCR-DGGE) y PCR en tiempo real fueron
asociadas para determinar la abundancia y diversidad de las comunidades
bacterianas que habitan el rumen de cabras criollas durante la patología digestiva
“timpanismo espumoso”
Network meta‐analysis of post‐exposure prophylaxis randomized clinical trials
Objectives: We performed a network meta‐analysis of PEP randomized clinical trials to evaluate the best regimen. /
Methods: After MEDLINE/Pubmed search, studies were included if: (1) were randomized, (2) comparing at least 2 PEP three‐drug regimens and, (3) reported completion rates or discontinuation at 28 days. Five studies with 1105 PEP initiations were included and compared ritonavir‐boosted lopinavir (LPV/r) vs. atazanavir (ATV) (one study), cobicistat‐boosted elvitegravir (EVG/c) (one study), raltegravir (RAL) (one study) or maraviroc (MVC) (two studies). We estimated the probability of each treatment of being the best based on the evaluation of five outcomes: PEP non‐completion at day 28, PEP discontinuation due to adverse events, PEP switching due to any cause, lost to follow‐up and adverse events. /
Results: Participants were mostly men who have sex with men (n = 832, 75%) with non‐occupational exposure to HIV (89.86%). Four‐hundred fifty‐four (41%) participants failed to complete their PEP course for any reason. The Odds Ratio (OR) for PEP non‐completion at day 28 in each antiretroviral compared to LPV/r was: ATV 0.95 (95% CI 0.58–1.56; EVG/c: OR 0.65 95% CI 0.30–1.37; RAL: OR 0.68 95% CI 0.41–1.13; and MVC: OR 0.69 95% CI 0.47–1.01. In addition, the rankogram showed that EVG/c had the highest probability of being the best treatment for the lowest rates in PEP non‐completion at day 28, switching, lost to follow‐up or adverse events and MVC for PEP discontinuations due to adverse events. /
Conclusions: Our study shows the advantages of integrase inhibitors when used as PEP, particularly EVG as a Single‐Tablet Regimen
Graph based study of allergen cross-reactivity of plant lipid transfer proteins (LTPs) using microarray in a multicenter study.
The study of cross-reactivity in allergy is key to both understanding. the allergic response of many patients and providing them with a rational treatment In the present study, protein microarrays and a co-sensitization graph approach were used in conjunction with an allergen microarray immunoassay. This enabled us to include a wide number of proteins and a large number of patients, and to study sensitization profiles among members of the LTP family. Fourteen LTPs from the most frequent plant food-induced allergies in the geographical area studied were printed into a microarray specifically designed for this research. 212 patients with fruit allergy and 117 food-tolerant pollen allergic subjects were recruited from seven regions of Spain with different pollen profiles, and their sera were tested with allergen microarray. This approach has proven itself to be a good tool to study cross-reactivity between members of LTP family, and could become a useful strategy to analyze other families of allergens
The early bee catches the flower - circadian rhythmicity influences learning performance in honey bees, Apis mellifera
Circadian rhythmicity plays an important role for many aspects of honey bees’ lives. However, the question whether it also affects learning and memory remained unanswered. To address this question, we studied the effect of circadian timing on olfactory learning and memory in honey bees Apis mellifera using the olfactory conditioning of the proboscis extension reflex paradigm. Bees were differentially conditioned to odours and tested for their odour learning at four different “Zeitgeber” time points. We show that learning behaviour is influenced by circadian timing. Honey bees perform best in the morning compared to the other times of day. Additionally, we found influences of the light condition bees were trained at on the olfactory learning. This circadian-mediated learning is independent from feeding times bees were entrained to, indicating an inherited and not acquired mechanism. We hypothesise that a co-evolutionary mechanism between the honey bee as a pollinator and plants might be the driving force for the evolution of the time-dependent learning abilities of bees
Effectiveness and safety of first-generation protease inhibitors in clinical practice: Hepatitis C virus patients with advanced fibrosis
AIM: To evaluates the effectiveness and safety of the first generation, NS3/4A protease inhibitors (PIs) in clinical practice against chronic C virus, especially in patients with advanced fibrosis.
METHODS: Prospective study and non-experimental analysis of a multicentre cohort of 38 Spanish hospitals that includes patients with chronic hepatitis C genotype 1, treatment-nai¨ve (TN) or treatment-experienced (TE),
who underwent triple therapy with the first generation NS3/4A protease inhibitors, boceprevir (BOC) and telaprevir (TVR), in combination with pegylated interferon and ribavirin. The patients were treatment in routine practice settings. Data on the study population and on adverse clinical and virologic effects were compiled during the treatment period and during follow up.
RESULTS: One thousand and fifty seven patients were included, 405 (38%) were treated with BOC and 652 (62%) with TVR. Of this total, 30% (n = 319) were TN and the remaining were TE: 28% (n = 298) relapsers, 12% (n = 123) partial responders (PR), 25% (n = 260) null-responders (NR) and for 5% (n = 57) with prior response unknown. The rate of sustained virologic response (SVR) by intention-to-treatment (ITT) was greater in those treated with TVR (65%) than in those treated with BOC (52%) (P < 0.0001), whereas by modified intention-to-treatment (mITT) no were found significant differences. By degree of fibrosis, 56% of patients were F4 and the highest SVR rates were recorded in the non-F4 patients, both TN and TE. In the analysis by groups, the TN patients treated with TVR by ITT showed a higher SVR (P = 0.005). However, by mITT there were no significant differences between BOC and TVR. In the multivariate analysis by mITT, the significant SVR factors were relapsers, IL28B CC and non-F4; the type of treatment (BOC or TVR) was not significant. The lowest SVR values were presented by the F4-NR patients, treated with BOC (46%) or with TVR (45%). 28% of the patients interrupted the treatment, mainly by non-viral response (51%): this outcome was more frequent in the TE than in the TN patients (57% vs 40%, P = 0.01). With respect to severe haematological disorders, neutropaenia was more likely to affect the patients treated with BOC (33% vs 20%, P = 0.0001), and thrombocytopaenia and anaemia, the F4 patients (P = 0.000, P = 0.025, respectively).
CONCLUSION: In a real clinical practice setting with a high proportion of patients with advanced fibrosis, effectiveness of first-generation PIs was high except for NR patients, with similar SVR rates being achieved by BOC and TVR
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