Miracle-dz/UniFAR-FTUs huggingface dataset:
Who stays and who leaves? Social dynamics surrounding employee turnover

My dissertation consists of two essays that examine employee turnover as an independent and a dependent variable. In my first essay I examine the relationship between job-related attitudes, such as job satisfaction and organizational commitment, and employee turnover behavior. In a sample of over 6,000 teachers in 200 public elementary schools, I found significant variability across employee and organizational characteristics in the strength of the relationship between job attitude ratings and turnover. I attribute this variability to two sources: (a) systematic differences in attitude thresholds, i.e. the minimum acceptable level of a job attitude necessary to remain with the organization; and (b) systematic response biases in attitude ratings. I develop a model to determine which characteristics relate to significant differences in attitude thresholds and/or response biasing factors and found that both individual and organizational attributes are distinguishing factors. In my second essay I present findings from three inter-related studies investigating human and social capital as mechanisms that may determine whether and why employee retention is associated with organizational performance. In a sample of public schools I found a linear relationship between employee retention and organizational performance. Further, this positive association is fully mediated by human capital and partially mediated by social capital. In addition, I examined human and social capital at the individual level of employees who remain with the organization versus those who leave. I found that organizational performance suffers most when the employees who leave have high levels of both human and social capital. Finally, I distinguished human and social capital losses based on their specificity: organization-specific versus task-specific. As predicted, the losses of task-specific human and social capital were more deleterious to organizational performance than the losses of organization-specific forms of capital.
Prisión común, imaginario social e identidad. Chile, 1870-1920.

La publicacion de este libro resulta ser el punto culminante en la decantacion que han experimentado los trabajos de investigacion sobre el desarrollo historico del sistema carcelario en Chile. Antes de este libro, los trabajos sobre el tema estaban acotados a su divulgacion en publicaciones o revistas especializadas sin gran difusion, reducidos solamente a los circuitos academicos. Es asi como esta publicacion renueva verdaderamente la discusion historiografica en Chile al aportar nuevas lineas de investigacion y al permitir continuar con el camino de abierta consolidacion que goza el trabajo historico de indagacion de los movimientos sociales encarnados por los sujetos populares.
Cross-Language Learning from Bots and Users to Detect Vandalism on Wikipedia

Vandalism, the malicious modification of articles, is a serious problem for open access encyclopedias such as Wikipedia. The use of counter-vandalism bots is changing the way Wikipedia identifies and bans vandals, but their contributions are often not considered nor discussed. In this paper, we propose novel text features capturing the invariants of vandalism across five languages to learn and compare the contributions of bots and users in the task of identifying vandalism. We construct computationally efficient features that highlight the contributions of bots and users, and generalize across languages. We evaluate our proposed features through classification performance on revisions of five Wikipedia languages, totaling over 500 million revisions of over nine million articles. As a comparison, we evaluate these features on the small PAN Wikipedia vandalism data sets, used by previous research, which contain approximately 62,000 revisions. We show differences in the performance of our features on the PAN and the full Wikipedia data set. With the appropriate text features, vandalism bots can be effective across different languages while learning from only one language. Our ultimate aim is to build the next generation of vandalism detection bots based on machine learning approaches that can work effectively across many languages.
Improper colourings of graphs

We consider a generalisation of proper vertex colouring of graphs, referred to as improper colouring, in which each vertex can only be adjacent to a bounded number t of vertices with the same colour, and we study this type of graph colouring problem in several different settings. The thesis is divided into six chapters. In Chapter 1, we outline previous work in the area of improper colouring. In Chapters 2 and 3, we consider improper colouring of unit disk graphs -- a topic motivated by applications in telecommunications -- and take two approaches, first an algorithmic one and then an average-case analysis. In Chapter 4, we study the asymptotic behaviour of the improper chromatic number for the classical Erdos-Renyi model of random graphs. In Chapter 5, we discuss acyclic improper colourings, a specialisation of improper colouring, for graphs of bounded maximum degree. Finally, in Chapter 6, we consider another type of colouring, frugal colouring, in which no colour appears more than a bounded number of times in any neighbourhood. Throughout the thesis, we will observe a gradient of behaviours: for random unit disk graphs and "large" unit disk graphs, we can greatly reduce the required number of colours relative to proper colouring; in Erdos-Renyi random graphs, we do gain some improvement but only when t is relatively large; for acyclic improper chromatic numbers of bounded degree graphs, we discern an asymptotic difference in only a very narrow range of choices for t.
A novel occlusion-free active recognition algorithm for objects in clutter

In this work we propose a new active recognition algorithm for objects in a highly cluttered environment. In contrast to conservative active recognition methods, where robots observe the scene from different viewpoints, our robots are capable of rearranging objects for better perspectives. The whole system bases on an analysis for the occlusion relationships between objects in the scene. After that, a moving strategy is presented to free the objects from occlusion. Experimental evaluations are conducted using a robot arm with an RGB-D sensor mounted on it.
IDIC: assembling video sequences from story plans and content annotations

Describes a system, IDIC, which can generate a video sequence according to a story plan by selecting appropriate segments from an archive of annotated video. IDIC uses a simple planner to generate its stories. By critically examining the strengths and weaknesses of the representation and algorithm employed in the planner, the authors are able to describe some interesting similarities and differences between planning and video story generation. They use their analysis of IDIC to investigate the representation and processing issues involved in the development of video generation systems. <<ETX>>
Somnography using unobtrusive motion sensors and Android-based mobile phones

Sleep plays a fundamental role in the life of every human. The prevalence of sleep disorders has increased significantly, now affecting up to 50% of the general population. Sleep is usually analyzed by extracting a hypnogram containing sleep stages. The gold standard method polysomnography (PSG) requires subjects to stay overnight in a sleep laboratory and to wear a series of obtrusive devices. This work presents an easy to use method to perform somnography at home using unobtrusive motion sensors. Ten healthy male subjects were recorded during two consecutive nights. Sensors from the Shimmer platform were placed in the bed to record accelerometer data, while reference hypnograms were collected using a SOMNOwatch system. A series of filters were used to extract a motion feature in 30 second epochs from the accelerometer signals. The feature was used together with the ground truth information to train a Naive Bayes classifiers that distinguished wakefulness, REM and non-REM sleep. Additionally the algorithm was implemented on an Android mobile phone. Averaged over all subjects, the classifier had a mean accuracy of 79.0 % (SD 9.2%) for the three classes. The mobile phone implementation was able to run in realtime during all experiments. In future this will lead to a method for simple and unobtrusive somnography using mobile phones.
Ill‐conditioning of the truncated singular value decomposition, Tikhonov regularization and their applications to numerical partial differential equations

This paper explores some intrinsic characteristics of accuracy and stability for the truncated singular value decomposition (TSVD) and the Tikhonov regularization (TR), which can be applied to numerical solutions of partial differential equations (numerical PDE). The ill‐conditioning is a severe issue for numerical methods, in particular when the minimal singular value sigmamin of the stiffness matrix is close to zero, and when the singular vector umin of σmin is highly oscillating. TSVD and TR can be used as numerical techniques for seeking stable solutions of linear algebraic equations. In this paper, new bounds are derived for the condition number and the effective condition number which can be used to improve ill‐conditioning by TSVD and TR. A brief error analysis of TSVD and TR is also made, since both errors and condition number are essential for the numerical solution of PDE. Numerical experiments are reported for the discrete Laplace operator by the method of fundamental solutions. Copyright © 2011 John Wiley & Sons, Ltd.
Characterization of human rheumatoid factors with seven antiidiotypes induced by synthetic hypervariable region peptides

Recently, we have used synthetic peptides corresponding to the complementarity-determining regions (CDR) of Ig molecules to induce antiidiotypic antisera. Peptide PSH3, representing the third CDR of the IgM rheumatoid factor (RF) Sie heavy (H) chain, induced a private antiidiotype that reacted with only one out of five IgM-RF. Peptide PSL2, corresponding to the second CDR of Sie light (L) chain, induced an antibody against a crossreactive idiotype (CRI), expressed by 10 out of 12 human IgM-RF analyzed. Herein, we report that five additional antiidiotypic antibodies were generated by immunization with synthetic peptides identical to the third L chain CDR of IgM-RF Sie (PSL3), the second and third H chain CDR of IgM-RF Wol, and the second and third CDR of IgM-RF Pom. As analyzed by immunoblot assay, both anti-PSL3 and anti-PSL2 reacted with the majority of 16 IgM-RF. In contrast, all five antiidiotypes induced by the H chain peptides reacted only with the parent proteins, except anti-PSH3, which reacted weakly with one additional RF. These results suggest that one (or very few) VL gene(s), but a larger number of VH genes, are used to encode IgM-RF autoantibodies.
The Ccr4-Not Complex Interacts with the mRNA Export Machinery

Background The Ccr4-Not complex is a key eukaryotic regulator of gene transcription and cytoplasmic mRNA degradation. Whether this complex also affects aspects of post-transcriptional gene regulation, such as mRNA export, remains largely unexplored. Human Caf1 (hCaf1), a Ccr4-Not complex member, interacts with and regulates the arginine methyltransferase PRMT1, whose targets include RNA binding proteins involved in mRNA export. However, the functional significance of this regulation is poorly understood. Methodology/Principal Findings Here we demonstrate using co-immunoprecipitation approaches that Ccr4-Not subunits interact with Hmt1, the budding yeast ortholog of PRMT1. Furthermore, using genetic and biochemical approaches, we demonstrate that Ccr4-Not physically and functionally interacts with the heterogenous nuclear ribonucleoproteins (hnRNPs) Nab2 and Hrp1, and that the physical association depends on Hmt1 methyltransferase activity. Using mass spectrometry, co-immunoprecipitation and genetic approaches, we also uncover physical and functional interactions between Ccr4-Not subunits and components of the nuclear pore complex (NPC) and we provide evidence that these interactions impact mRNA export. Conclusions/Significance Taken together, our findings suggest that Ccr4-Not has previously unrealized functional connections to the mRNA processing/export pathway that are likely important for its role in gene expression. These results shed further insight into the biological functions of Ccr4-Not and suggest that this complex is involved in all aspects of mRNA biogenesis, from the regulation of transcription to mRNA export and turnover.
A Framework for Clustering Uncertain Data

The challenges associated with handling uncertain data, in particular with querying and mining, are finding increasing attention in the research community. Here we focus on clustering uncertain data and describe a general framework for this purpose that also allows to visualize and understand the impact of uncertainty---using different uncertainty models---on the data mining results. Our framework constitutes release 0.7 of ELKI (http://elki.dbs.ifi.lmu.de/) and thus comes along with a plethora of implementations of algorithms, distance measures, indexing techniques, evaluation measures and visualization components.
Concerted action of two avirulent spore effectors activates Reaction to Puccinia graminis 1 (Rpg1)-mediated cereal stem rust resistance

The barley stem rust resistance gene Reaction to Puccinia graminis 1 (Rpg1), encoding a receptor-like kinase, confers durable resistance to the stem rust pathogen Puccinia graminis f. sp. tritici. The fungal urediniospores form adhesion structures with the leaf epidermal cells within 1 h of inoculation, followed by hyphae and haustorium formation. The RPG1 protein is constitutively expressed and not phosphorylated. On inoculation with avirulent urediniospores, it is phosphorylated in vivo within 5 min and subsequently degraded. Application of arginine-glycine-aspartic acid peptide loops prevented the formation of adhesion structures for spore attachment, the phosphorylation of RPG1, and germination of the viable spores. Arginine-glycine-aspartic acid affinity chromatography of proteins from the ungerminated avirulent rust spores led to the purification and identification of a protein with fibronectin type III and breast cancer type 1 susceptibility protein domains and a vacuolar protein sorting-associated protein 9 with a coupling of ubiquitin to endoplasmic reticulum degradation domain. Both proteins are required to induce in vivo phosphorylation and degradation of RPG1. Combined application of both proteins caused hypersensitive reaction on the stem rust-resistant cultivar Morex but not on the susceptible cultivar Steptoe. Expression studies indicated that mRNA of both genes are present in ungerminated urediniospores and are constitutively transcribed in sporelings, infected leaves, and haustoria in the investigated avirulent races. Evidence is presented that RPG1, in yeast, interacts with the two protein effectors from the urediniospores that activate cooperatively the stem rust resistance protein RPG1 long before haustoria formation.
Differential expression of matrilysin‐1 (MMP‐7), 92 kD gelatinase (MMP‐9), and metalloelastase (MMP‐12) in oral verrucous and squamous cell cancer

Squamous cell carcinoma (SCC) of the oral cavity is a highly invasive tumour of stratified squamous epithelium that spreads through degradation of the basement membrane (BM) and extracellular matrix (ECM). There are currently no reliable tissue or serum markers to predict whether the tumour has metastasized at the time of diagnosis. Verrucous carcinoma (VC) of the oral cavity is a rare low‐grade variant of oral SCC that penetrates into the subepithelial connective tissue. Many matrix metalloproteinases (MMPs), such as MMP‐1, ‐2, ‐7, ‐9, ‐13, and ‐14, as well as integrin receptors have been implicated in cancer invasion. Integrin αvβ6 is induced in SCC and appears to be involved in up‐regulation of MMP‐9 expression by oral keratinocytes and promotion of their migration. The aim of this study was to investigate whether the pattern of MMP expression or that of αvβ6 integrin contributes to the differences in the biological behaviour of oral SCC and VC. The results show that the less aggressive nature of oral VC may be connected to its MMP expression profile. Typically, VCs were devoid of epithelial MMP‐3, ‐7, ‐9, ‐12 and ‐13 expression, compared with SCCs. MMP‐19 was expressed by epithelial keratinocytes in hyperproliferative areas of verrucous hyperplasia, VC, and SCC, but was absent in the invasive cancer cell nests of SCC. MMP‐26 was expressed by hyperproliferative keratinocytes in VC as well as by invasive cancer cells in SCCs. MMP‐10 was expressed widely in the epithelium of all SCC specimens. αvβ6 integrin expression was also detected in some cases of epithelial hyperplasia but was significantly more abundant in cancers at the invasive front. The absence of MMP‐7, ‐9 and ‐12 from epithelial cells may serve as a good prognostic marker of non‐invasive oral carcinoma. Blocking the activity of invasion‐specific MMPs or αvβ6 integrin might offer novel therapeutic modalities in early‐stage oral carcinoma. Copyright © 2003 John Wiley & Sons, Ltd.
SURF-2: A program for dependability evaluation of complex hardware and software systems

SURF-2, a software tool for evaluating system dependability, is described. It is especially designed for an evaluation-based system design approach in which multiple design solutions need to be compared from the dependability viewpoint. System behavior may be modeled either by Markov chains or by generalized stochastic Petri nets. The tool supports the evaluation of different measures of dependability, including pointwise measures, asymptotic measures, mean sojourn times and, by superposing a reward structure on the behavior model, reward measures such as expected performance or cost.
A cost-efficient self-checking register architecture for radiation hardened designs

The rapid development of CMOS technology has significantly increased the susceptibility of electronic systems to radiation-induced soft errors. Conventional error-tolerant techniques typically use redundancies to mitigate soft errors and increase system immunity. However they do not have self-checking capabilities, and therefore are still vulnerable to the errors in the redundant circuitry added for error-tolerance. This paper proposes a novel self-checking soft error-tolerant register based on SETTOFF, a Soft Error and Timing error Tolerant Flip-Flop. The register significantly improves the error-tolerant capability over previous techniques since it has a self-checking capability, which allows the register to tolerate both the errors in the original flip-flops and the redundant circuitry. In addition, the register can also tolerate both soft errors (SETs and SEUs) and timing errors. Compared with other previous techniques such as TMR, the proposed register reduces the power consumption overhead by 81%, and the delay overhead by 54% in 65nm technology; The area overhead is also reduced by 25%.
Visual search tasks: the effects of head-up displays on driving and task performance

This study investigated the differences between head-up display (HUD) and head-down display (HDD) systems in vehicles with the ultimate goal of increasing driver performance and safety. Our initial focus was on comparing drivers' visual task performance (and associated driving behavior) while using a HUD and HDD. In a medium-fidelity driving simulator, 16 experienced drivers performed two types of tasks, a structured (text) and a semi-structured (grid) visual search task while driving. They first completed a baseline drive using a driving simulator with no secondary tasks followed by four drives under various conditions: HUD-Text, HUD-Grid, HDD-Text, and HDD-Grid. The study returned mixed results. HUDs generally contributed to more secondary task errors, but overall, users still preferred to use HUDs over HDDs. The response time to complete tasks was unevenly affected by display type. While there was no difference between response times in the grid tasks (HDD vs. HUD), the HUD was associated with significantly faster task performance as compared to the text tasks. These results suggest that HUDs may offer advantages to drivers in some task scenarios but more research is needed to understand under what conditions they do not add value.
Towards protocol equilibrium with oblivious routers

Currently, the Internet is dominated by TCP traffic. TCP is congestion aware, shares bandwidth with other TCP flows, and is stable because most flows are congestion reactive. It has been shown that current AQM schemes may not be resistant to greedy traffic agents. Thus, it is important to study mechanisms which provide incentives to greedy agents to come to an equilibrium state in their own selfish interest. In addition, we want our AQM schemes to he oblivious to the flows identities which makes them easier to scale and deploy. In this paper, we show that if routers used EWMA to measure the aggregate rate, then the best strategy for a selfish agent to minimize its losses is to arrive at a constant rate. Even though the protocol space is arbitrary, our scheme ensures that the best greedy strategy is simple, i.e. send with CBR. Then, we show how we can use the results of an earlier paper to enforce simple and efficient protocol equilibria on selfish traffic agents
UbiA, the major polyubiquitin locus in Caenorhabditis elegans, has unusual structural features and is constitutively expressed

Ubiquitin is a multifunctional 76-amino-acid protein which plays critical roles in many aspects of cellular metabolism. In Caenorhabditis elegans, the major source of ubiquitin RNA is the polyubiquitin locus, UbiA. UbiA is transcribed as a polycistronic mRNA which contains 11 tandem repeats of ubiquitin sequence and possesses a 2-amino-acid carboxy-terminal extension on the final repeat. The UbiA locus possesses several unusual features not seen in the ubiquitin genes of other organisms studied to date. Mature UbiA mRNA acquires a 22-nucleotide leader sequence via a trans-splicing reaction involving a 100-nucleotide splice leader RNA derived from a different chromosome. UbiA is also unique among known polyubiquitin genes in containing four cis-spliced introns within its coding sequence. Thus, UbiA is one of a small class of genes found in higher eucaryotes whose heterogeneous nuclear RNA undergoes both cis and trans splicing. The putative promoter region of UbiA contains a number of potential regulatory elements: (i) a cytosine-rich block, (ii) two sequences resembling the heat shock regulatory element, and (iii) a palindromic sequence with homology to the DNA-binding site of the mammalian steroid hormone receptor. The expression of the UbiA gene has been studied under various heat shock conditions and has been monitored during larval moulting and throughout the major stages of development. These studies indicate that the expression of the UbiA gene is not inducible by acute or chronic heat shock and does not appear to be under nutritional or developmental regulation in C. elegans.