The happiness paradox: your friends are happier than you

Most individuals in social networks experience a so-called Friendship Paradox: they are less popular than their friends on average. This effect may explain recent findings that widespread social network media use leads to reduced happiness. However the relation between popularity and happiness is poorly understood. A Friendship paradox does not necessarily imply a Happiness paradox where most individuals are less happy than their friends. Here we report the first direct observation of a significant Happiness Paradox in a large-scale online social network of $39,110$ Twitter users. Our results reveal that popular individuals are indeed happier and that a majority of individuals experience a significant Happiness paradox. The magnitude of the latter effect is shaped by complex interactions between individual popularity, happiness, and the fact that users cluster assortatively by level of happiness. Our results indicate that the topology of online social networks and the distribution of happiness in some populations can cause widespread psycho-social effects that affect the well-being of billions of individuals.Comment: 15 pages, 3 figures, 2 table

Molecular genetic characterization of ataxic movement disorders in mouse and human

Deletion at ITPR1 underlies a young onset autosomal recessive ataxia in mice and a late onset autosomal dominant ataxia (SCA15) in humans. Data presented show the utility of investigating spontaneous mouse mutations in understanding human disease. Through linkage and sequence analysis a novel mutation in the gene encoding inositol 1,4,5-triphosphate receptor type 1 was identified to underlie a severe movement disorder in mice. The 18bp in frame deletion in Itpr1 exon 36 was shown to be allelic to that of another model, opisthotonos (Lane 1972). The Itpr1Δ18 mutation leads to a decreased to almost total lack in the normally high level of ITPR1 expression in cerebellar Purkinje cells. In addition, high density genome wide SNP genotype data in humans showed a SUMF1-ITPR1 deletion to segregate with spinocerebellar ataxia 15 (SCA15), a late-onset autosomal dominant disorder, which was previously mapped to the genomic region containing ITPR1; however, no causal mutations had been identified (Knight et al. 2003). With this deletion not observed in a control population, decreased ITPR1 protein levels in individuals carrying the deletion, and subsequent identification of similar deletions in additional spinocerebellar ataxia families, the data provide compelling evidence that heterozygous deletion in ITPR1 underlies SCA15. As demonstrated, high density genome wide SNP analysis can facilitate rapid detection of structural genomic mutations that may underlie disease when standard sequencing approaches are insufficient. The data suggest genetic alterations at ITPR1 underlie approximately over 1% of autosomal dominant SCA type III (ADCA III) cases for which currently no genetic cause has been identified. Data described herein add weight to a role for aberrant intracellular Ca2+ signaling in Purkinje cells in the pathogenesis of spinocerebellar ataxia

Integrating Battery-Less Energy Harvesting Devices in Multi-hop Industrial Wireless Sensor Networks

Industrial wireless sensor networks enable real-time data collection, analysis, and control by interconnecting diverse industrial devices. In these industrial settings, power outlets are not always available, and reliance on battery power can be impractical due to the need for frequent battery replacement or stringent safety regulations. Battery-less energy harvesters present a suitable alternative for powering these devices. However, these energy harvesters, equipped with supercapacitors instead of batteries, suffer from intermittent on-off behavior due to their limited energy storage capacity. As a result, they struggle with extended or frequent energy-consuming phases of multi-hop network formation, such as network joining and synchronization. To address these challenges, our work proposes three strategies for integrating battery-less energy harvesting devices into industrial multi-hop wireless sensor networks. In contrast to other works, our work prioritizes the mitigation of intermittency-related issues, rather than focusing solely on average energy consumption, as is typically the case with battery-powered devices. For each of the proposed strategies, we provide an in-depth discussion of their suitability based on several critical factors, including the type of energy source, storage capacity, device mobility, latency, and reliability.Comment: This work has been submitted to the IEEE for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessibl

Final follicular maturation in the cow and its effects on the developmental potential of the oocyte

The use of assisted reproduction techniques can generate up to 27 (superovulation, SO) or 50 (in vitro embryo production, IVP) calves per cow per year instead of only one calf per cow per year after normal mating. That is due to the possibility to use more than one oocyte per estrous cycle; namely on average 15 (SO) and 60 (IVP). However, using these techniques, the efficiency per used oocyte decreases dramatically. Instead of the efficient use of oocytes during natural mating, only 30% efficiency is reached with SO. Furthermore, IVP generates only 8 calves per 100 used immature oocytes. This loss in efficiency might be due to deviations that occur during the final maturation of the oocytes. In this thesis concepts of final follicular maturation in unstimulated normally cyclic cows are applied to maturation during SO and IVP in order to gain better understanding of deviations in follicle and oocyte development using these techniques. Also preovulatory follicular development after SO is used as a model to study maturation in vivo. Chapter 1 introduces the subject. Deviations in preovulatory follicular development as induced using SO or as a result of oocyte collection and maturation during IVP are discussed against the background of the course of follicular maturation in unstimulated normally cyclic cows. In cows treated for SO the period of preovulatory follicular development is reduced compared to this period in unstimulated normally cyclic cows. Also, after SO an asynchrony of development is found within the population of stimulated follicles as well as between the follicle and its oocyte. For IVP, oocytes are usually collected from 3-6 mm follicles. These follicles lack part of the processes of follicular growth and selection. Furthermore, during in vitro maturation (IVM) of the collected immature oocytes, deviations in cytoplasmic maturation are frequently found. In chapter 2, the effect of prolongation of the period of preovulatory follicular development after SO on the heterogeneity of the population of preovulatory follicles and their oocytes with respect to the potential to mature, to ovulate, to be fertilized and to develop into embryos was investigated. In eCG-stimulated heifers, the spontaneous occurrence of the LH surge was suppressed with a norgestomet ear implant and at a later time a LH surge was induced using GnRH. The protocol resulted in a LH surge at the desired time in 100% of the cases. Prolongation of the period of preovulatory follicular development from 42.4 to 53.8 h increased ovulation rates with 25%. It was suggested that the heterogeneity of the follicular population, as is present in normally stimulated heifers at the time of the spontaneous LH surge, was reduced. The increased ovulation rates did not coincide with an increased number of embryos at day 7 after fertilization. The treatment with norgestomet did not adversely affect Chapter 8?Chapter 8 122 final maturation and fertilization. However, the treatment might have disturbed early embryonic development by altering the secretory activity of the cells of the epithelium of the oviduct. The superovulation protocol with LH surge induction (chapter 2) was used in the studies described in chapter 3 and 4 to obtain oocytes at a fixed stage of development in vivo. In chapter 3, it was investigated to what extend IVM contributes to limiting yields of viable embryos in currently used IVP programs. The use of in vivo matured oocytes, collected from eCG-stimulated heifers at 22-24 h after the LH surge, instead of in vitro matured oocytes collected from 2-8 mm sized follicles, for IVF and IVC improved blastocyst formation and hatching with 100%. Additionally, also the progress of embryonic development was different for the two groups of oocytes; both blastocyst formation and hatching of blastocysts progressed slower for in vivo matured oocytes than for in vitro matured oocytes. The decreased embryonic development after IVM (chapter 3) might be due to the maturation conditions per se or to a difference in startcompetence of the oocytes collected from 2-8 mm sized follicles when compared to the oocytes from preovulatory follicles generated in eCG-treated cows. In chapter 4 the significance of the conditions during maturation for efficient IVP was tested using oocytes for in vivo maturation and IVM which presumably had an equivalent startcompetence. Therefore, heifers were stimulated with eCG using the same protocol as described in chapter 2. From part of the heifers, oocytes from preovulatory follicles were collected at the presumptive time of the LH surge and subsequently subjected to IVM. From the other heifers, oocytes from preovulatory follicles were collected 22-24 h after the occurrence of an induced LH surge. Both groups of oocytes were subjected to IVF and IVC. Blastocyst formation and hatching rates were significantly lower after in vitro maturation than after in vivo maturation of the oocytes. It was concluded that the conditions during IVM are an important factor responsible for limited yield after IVP. In this study, the progress of embryonic development was similar for both groups of oocytes and was conform to that as observed for the in vivo matured oocytes in chapter 3. Since in that study in vitro matured oocytes from 2-8 mm follicles developed at a faster rate than in vivo matured oocytes from preovulatory follicles it was suggested that oocytes undergo certain changes during follicular development from 2-8 mm to preovulatory stage at onset of final maturation which may be involved in programming embryonic development. Both in the studies described in chapter 3 and 4, a large variation in blastocyst formation between individual heifers was found, which is probably due to differences in response to superovulatory treatment. When in the group of heifers donating the in vitro matured oocytes (chapter 4) heifers with exceptional follicular function on the basis of estradiol-17ß and progesterone concentrations in the follicular fluid (FF) were excluded, rates of blastocyst formation increased indicating that the steroid producing capacity of the follicular wall influences oocyte quality. In chapter 5 and 6 preovulatory follicular development after eCG-treatment for SO was used as a model to study the possible role of the insulin-like growth factor (IGF)?Summary 123 system during final maturation in vivo. Earlier results from in vitro studies suggested a stimulatory role of IGF-I on growth and differentiation of granulosa cells and on final maturation of the oocyte. IGF binding proteins (IGFBPs) are suggested to decrease bioavailability of IGF-I but also individual functions of these IGFBPs on follicle and oocyte maturation can not be excluded. In chapter 5, levels of IGF-I and IGFBPs in the FF of eCG-stimulated follicles with normal and deviant follicular function on the basis of steroid hormones in the FF were compared at several times during final maturation. Final maturation in eCG-stimulated preovulatory follicles with normal function was characterized by rather constant levels of IGF-I and IGFBP3 in the FF. Low molecular weight IGFBPs (LMW IGFBPs, i.e. IGFBP2, -4 and -5) were absent in FF at the time the oocyte undergoes germinal vesicle breakdown (GVBD) and reaches metaphase I (MI). Just prior to ovulation, in 15% of the FF of the follicles with normal function, LMW IGFBPs were found. While the levels of IGF-I and IGFBP3 in the fluid of deviant follicles were not different when compared to eCG-stimulated follicles with normal function, the presence of LMW IGFBPs was different in these follicles; at the onset of final maturation, 35% of the deviant follicles contained LMW IGFBPs. All these follicles, except one, were classified deviant due to too low estradiol-17ß concentrations, probably a sign of atresia. During final maturation, LMW IGFBPs were occasionally found (GVBD, MI) or absent (just prior to ovulation) in deviant follicles. It was concluded that only a permissive role of IGF-I in final maturation can be expected. It was also concluded that, as in unstimulated, normally cyclic cows, low estradiol-17ß concentration in the FF of large follicles (> 8mm) coincided with the presence of LMW IGFBPs. The appearance of LMW IGFBPs in the FF of follicles with normal follicular function just prior to ovulation indicated a different role of the IGF system during ovulation and corpus luteum formation. Because different IGFBP patterns were found in the FFs of eCG-stimulated follicles with deviant follicular function and of concurrently developing follicles with normal follicular function, eCG stimulated follicles were used to study the regulation of the presence of IGFBPs during preovulatory follicular development (Chapter 6). Using reverse transcriptase-polymerase chain reaction (RT-PCR), mRNA levels for LMW IGFBPs were analyzed (semi-quantitatively) in eCG-stimulated preovulatory follicles at the onset of maturation with normal or deviant function, on the basis of estradiol-17ß concentrations in their FF. No or small differences in gene expression were found. Therefore, it was concluded that the earlier found difference in the presence of LMW IGFBPs in FF could not be explained by a difference in gene expression for these IGFBPs in the wall of the follicle. Thus, regulation of the presence of these proteins has to take place at the level of translation or protein degradation. Finally, in chapter 8, the results of the performed experiments are discussed against the background of the current knowledge and existing hypotheses on final follicular maturation. Possible directions of future research in order to improve the efficiency of assisted reproduction are discussed

Profiling gene expression in whole blood samples following an in-vitro challenge

Genomics tools (gene- and protein-expression studies) can be used to find possible target genes involved in a quantifiable trait or disease state. However in many instances, cells and tissues directly involved in the trait's expression, for example, brain tissue, are not amenable for gene expression analysis. Whole blood cells share a molecular make-up for cellular communication and gene regulation systems with many other cell types, for example, neuronal cells, and have the advantage of being very accessible for gene profiling. We investigated the feasibility of nationwide blood sample collection for lymphocyte RNA isolation and real-time PCR analysis to quantify genomic responses. We tested several designs for blood collection and storage: blood sampling in PAXgene blood collection tubes and storage at -20°C, blood sampling in heparin tubes and decanting the samples (with or without in-vitro stimulus) into either PAXgene blood collection tubes and storage at -20°C, or polypropylene tubes followed by snap-freezing and storage at -80°C. The latter procedure is the best cost-wise when only small amounts of total RNA are needed for downstream applications. Lymphocyte gene expression studies are most likely hampered by the quality of isolated RNA rather than the sampling method. We show that large-scale nationwide sample collections did not alter RNA quality or gene expression levels when compared to sampling and processing in a more controlled way. To this end, we present an optimized protocol for easy and standardized isolation of high quality RNA using the PAXgene isolation kit. Based on these results, we suggest that whole blood genomic data can be used as a genomic probe in experimental and clinical research

Influence du sentiment d’efficacité informatique sur les usages d’internet des étudiants

Face au développement des supports informatiques et au recours aux technologies de l’information et de la communication (TIC) dans l’enseignement supérieur et l’insertion socioprofessionnelle, cet article se focalise sur une compétence transversale majeure : la maîtrise de l’informatique et d’internet. L’étude évalue les déterminants principaux des usages d’internet par les étudiants, en distinguant les usages en général et les usages spécifiques aux études. Les résultats montrent que ces usages sont fortement liés au rapport subjectif que les étudiants entretiennent vis-à-vis de ces technologies, aux attentes qu’ils en ont et à leur sentiment d’efficacité personnelle dans la maîtrise de ces outils.Facing the development of computer products and ICT in higher education, socioprofessional insertion and employment, this article is focused on one major competence which refers to human computer interaction and Internet expertise. The study evaluates the main determinants of students’ internet uses, distinguishing general and academic uses. The results show that these uses are strongly related to the subjective perception that the students have about these technologies, to their expectations and to their computer and internet self-efficacy

Threats Arising from Software Gamification

The appearance of gamification dates back about a decade and since this tool has been increasingly used not only in the entertainment sector but also in the industry, army, education, health and others. Studies suggest that this approach may provide added value outcomes, in particular in the users’ motivational and engagement areas, in a wide range of fields such as customer relations, skills learning, physical exercises, health management, etc. On the other hand, the consequences and potential risks related to its use remain insufficiently understood and have started to become the object of research in the last years. This chapter aims at exploring and deepening the understanding of the possible threats resulting from the use of software gamification at both the individual and collective levels. To do so, an integrative literature review was carried out on studies examining the negatives effects and challenges of this tool so as to identify the possible adverse impacts arising from them. Overall, results would show that an inadequate gamification design and implementation and its implications in terms of a flawed rewarding system and ethical issues may entail perils such as demotivating users, engendering mistrust, health issues and tarnishing the gamification credibility as well as that of the management in charge of it

The opportunities and challenges of using Drosophila to model human cardiac diseases

The Drosophila heart tube seems simple, yet it has notable anatomic complexity and contains highly specialized structures. In fact, the development of the fly heart tube much resembles that of the earliest stages of mammalian heart development, and the molecular-genetic mechanisms driving these processes are highly conserved between flies and humans. Combined with the fly’s unmatched genetic tools and a wide variety of techniques to assay both structure and function in the living fly heart, these attributes have made Drosophila a valuable model system for studying human heart development and disease. This perspective focuses on the functional and physiological similarities between fly and human hearts. Further, it discusses current limitations in using the fly, as well as promising prospects to expand the capabilities of Drosophila as a research model for studying human cardiac diseases