Miracle-dz/UniFAR-FTUs huggingface dataset:
To Fail or Not to Fail: A Z-score for Open Source Projects

This research is focused towards the prediction of Free Libre Open Source (FLOSS) project failure and non failure. By using the characteristics of open source projects, referred to as determinants, we strive to create a classification model that predicts project failure and additionally, project non-failure. Examples of project characteristics are the number of developers, the number of downloads, the number of releases and other indicators that relate to success or failure. In order to arrive at such classification model, we adopted the method to predict corporate bankruptcy by E. Altman, also known as the Z-score in economic context. The research method employed by Altman provides us with the necessary steps towards a classification method for FLOSS project failure. That is, creating a sample based on a priori groupings (failed and non-failed projects), possibly one year prior to the event, and performing multiple discriminant analysis to create a linear function that best discriminates between the chosen groups. This enables project administrators, or other stakeholders of open source projects, to assess their project outcome and possibly steer it into a more successful outcome. The Z-score model for open source projects, as we have named it, is able to predict 65% of the cases correctly. Meaning, any new project can be classified with 65% accuracy for its outcome, being a failure or non-failure. Furthermore, the model works best for predicting open source project failure, as approximately 70% of the cases can be correctly predicted. Although we believe that essential indicators for open source success or health are hard to measure in numeric values, making the classification model only a reflection of data that can be operationalized, we believe this is first step towards a concrete model to assess open source projects.
Wideband spectrum detection based on Compressed Sensing in cooperative cognitive radio networks

Compressed Sensing (CS) is a promising theory that has the power to reconstruct a certain signal from far fewer samples than conventional methods. Wideband detection is a challenge in Cognitive Radio (CR) networks because of its requirement for high sampling rate. Recent research shows that CS theory can be well applied to wideband detection with much lower sampling rates. In this paper, we propose a novel iterative algorithm for the noise-involved wideband detection in CR networks. In the proposed scheme, based on the different current detection results, the weights of the Weighted l1 Minimization (WP1) are adjusted adaptively with the aim of improving the detection result in the next iteration. We also utilize M-out-of-N method in the fusion center to improve our detection result. Finally we introduce a metric which provides a better measurement for the detection performance. Simulation results prove our algorithm to be effective with lower sampling rate.
Development of Microfabricated Biohybrid Artificial Lung Modules

Current artificial lungs, or membrane oxygenators, have limited gas exchange capacity due to their inability to replicate the microvascular scale of the natural lungs. Typical oxygenators have a surface area of 2 - 4 m2, surface area to volume ratio of 30 cm-1, and gas diffusion distances of 10 - 30 microns. In comparison, the natural lungs have a surface area of 100 m2, surface area to volume ratio of 300 cm-1, and diffusion distances of only 1 - 2 microns. Membrane oxygenators also suffer from biocompatibility complications, requiring systemic anticoagulation and limiting length of use. The goal of this thesis was to utilize microfabrication and tissue engineering techniques to develop biohybrid artificial lung modules to serve as the foundation of future chronic respiratory devices. Microfabrication techniques allow the creation of compact and efficient devices while culturing endothelial cells in the blood pathways provide a more biocompatible surface. Soft lithography techniques were used to create 3-D modules that contained alternating layers of blood microchannels and gas pathways in poly(dimethylsiloxane) (PDMS). The blood microchannels were fabricated with widths of 100 microns, depths of 30 microns, and inter-channel spacing of 50 microns. The diffusion distance between the blood and gas pathways was minimized and a surface area to blood volume ratio of 1000 cm-1 was achieved. The gas permeance of the modules was examined and maximum values of 9.16 x 10-6 and 3.55 x 10-5 ml/s/cm2/cmHg, for O2 and CO2 respectively, were obtained. Initial work examining thrombosis in non-endothelialized modules demonstrated the need for endothelial cells (ECs). Several surface modifications were explored to improve EC adhesion and growth on PDMS. Finally, endothelial cells were seeded and dynamically cultured in prototype modules. Confluent and viable cell monolayers were achieved after ten days. The work described in this thesis provides a strong foundation for creating more compact and efficient biohybrid artificial lungs devices.
Haloperidol modifies instrumental aspects of slot machine gambling in pathological gamblers and healthy controls

Instrumental conditioning has been implicated in persistence at slot machine gambling, but its specific role remains unclear. Dopamine (DA) mediates aspects of instrumental responding, and D2 antagonists reliably alter this process. This study investigated the effects of the preferential D2 antagonist, haloperidol (3 mg) on reward‐related betting behavior in 20 subjects with pathological gambling (PG) and 18 healthy Controls. Hierarchical regression assessed the prospective relationship between Payoff and Bet Size on consecutive trials, along with potential moderating effects of Cumulative Winnings and Phase of game (early/late) under drug and placebo. Payoff predicted Bet Size on the next trial regardless of other factors, consistent with an instrumental view of slot machine gambling. Under placebo, this correlation varied as a function of Winnings and Phase in PG subjects but was strong and invariant in Controls. Under haloperidol, the Payoff–Bet Size correlation in PG subjects resembled the invariant pattern of Controls under placebo. In contrast, the Payoff–Bet Size correlation rose then fell sharply over trials under haloperidol in controls. The correlation of Payoff with Bet Size is remarkable given that there is no actual contingency between winning and betting, and suggests that reward expectancies largely drive slot machine gambling. By blocking inhibitory D2 receptors, haloperidol may have reversed ‘tolerance’ to monetary reward mediated by increased tonic DA in PG subjects. Disturbance of the Payoff–Bet Size correlation in Controls may reflect indiscriminate reward signaling under haloperidol in subjects with normal DA function. Indirect enhancement of DA transmission may reduce undue reward‐related responding in PG subjects.
European Language Translation with Weighted Finite State Transducers: The CUED MT System for the 2008 ACL Workshop on SMT

We describe the Cambridge University Engineering Department phrase-based statistical machine translation system for Spanish-English and French-English translation in the ACL 2008 Third Workshop on Statistical Machine Translation Shared Task. The CUED system follows a generative model of translation and is implemented by composition of component models realised as Weighted Finite State Transducers, without the use of a special-purpose decoder. Details of system tuning for both Europarl and News translation tasks are provided.
Failing to Forget

Most people have experienced distressing events that they would rather forget. Although memories of such events become less intrusive with time for the majority of people, those with posttraumatic stress disorder (PTSD) are afflicted by vivid, recurrent memories of their trauma. Often triggered by reminders in the daily environment, these memories can cause severe distress and impairment. We propose that difficulties with intrusive memories in PTSD arise in part from a deficit in engaging inhibitory control to suppress episodic retrieval. We tested this hypothesis by adapting the think/no-think paradigm to investigate voluntary memory suppression of aversive scenes cued by naturalistic reminders. Retrieval suppression was compromised significantly in PTSD patients, compared with trauma-exposed control participants. Furthermore, patients with the largest deficits in suppression-induced forgetting were also those with the most severe PTSD symptoms. These results raise the possibility that prefrontal mechanisms supporting inhibitory control over memory are impaired in PTSD.
Extended Locality-Constrained Linear Self-Coding for Saliency Detection

In complex scenes, foreground saliency can hardly be detected completely, which may further result in the ambiguous cues of objects for other computer vision tasks. In this letter, an extended locality-constrained linear self-coding (eLLsC) scheme is proposed to assist to solve the saliency detection problem under the complex scenes. The locality of both spatial relation and feature distance is preserved in eLLsC, thus making the transformed code involved in the manifold ranking to prompt the generation of the saliency map with more complete foreground and clearer boundary. Experimental results on three saliency detection benchmarks demonstrate the effectiveness of the proposed hybrid method.
Rapid Signaling at Inhibitory Synapses in a Dentate Gyrus Interneuron Network

Mutual synaptic interactions between GABAergic interneurons are thought to be of critical importance for the generation of network oscillations and for temporal encoding of information in the hippocampus. However, the functional properties of synaptic transmission between hippocampal interneurons are largely unknown. We have made paired recordings from basket cells (BCs) in the dentate gyrus of rat hippocampal slices, followed by correlated light and electron microscopical analysis. Unitary GABAAreceptor-mediated IPSCs at BC–BC synapses recorded at the soma showed a fast rise and decay, with a mean decay time constant of 2.5 ± 0.2 msec (32°C). Synaptic transmission at BC–BC synapses showed paired-pulse depression (PPD) (32 ± 5% for 10 msec interpulse intervals) and multiple-pulse depression during repetitive stimulation. Detailed passive cable model simulations based on somatodendritic morphology and localization of synaptic contacts further indicated that the conductance change at the postsynaptic site was even faster, decaying with a mean time constant of 1.8 ± 0.6 msec. Sequential triple recordings revealed that the decay time course of IPSCs at BC–BC synapses was approximately twofold faster than that at BC–granule cell synapses, whereas the extent of PPD was comparable. To examine the consequences of the fast postsynaptic conductance change for the generation of oscillatory activity, we developed a computational model of an interneuron network. The model showed robust oscillations at frequencies >60 Hz if the excitatory drive was sufficiently large. Thus the fast conductance change at interneuron–interneuron synapses may promote the generation of high-frequency oscillations observed in the dentate gyrusin vivo.
Fracture phenomenology and toughness of filled natural rubber compounds via the pure shear test specimen

ABSTRACT Material anisotropy induced by strain in filled vulcanized rubbers strongly affects fracture toughness. The influence of carbon black content on fracture phenomenology and fracture toughness was investigated by performing video-recorded tests adopting a suitable grooved notched pure shear test specimen. In such a way, it was possible to analyze the so-called “knotty tearing” deformation mechanism occurring at the crack tip: sideways cracks perpendicular to the notch plane develop before the onset and propagation of a forward crack parallel to the notch plane. The J-integral fracture mechanics approach was adopted and digital image correlation analysis was performed to measure the strain at the crack tip. The presence of carbon black modifies the maximum chain extensibility and strain-induced crystallizability of the rubber matrix in the compound. The formation of sideways cracks occurred in all filled compounds and resulted in a link to the maximum chain extensibility. Nevertheless, toughness enh.
A coordinated control method for leveling output power fluctuations of multiple PV systems

A photovoltaic (PV) systempsilas power output fluctuates with the change of weather conditions. Frequency deviations, tie line voltage fluctuations etc. are caused by fluctuating PV power when large PV power from several PV systems is penetrated in the utility. In this paper, to overcome these problems, a simple coordinated control method for leveling the fluctuations of combined PV power from multiple PV systems is proposed. Here, output power command is generated in two steps: central and local. Fuzzy control is used to generate the central leveling output power command considering insolation, variance of insolation and absolute average of frequency deviation. In local step, a simple coordination is maintained between central power command and local power commands by producing a common tuning factor. Power converters are used to achieve the same output power as local command power employing PI control law for each of the PV generation systems. The proposed method is compared with the method where conventional maximum power point tracking (MPPT) control is used for each of the PV systempsilas power output. Simulation results show that the proposed method is effective for leveling output power fluctuations and feasible to reduce the frequency deviations of the power utility.
Dual use of Diff-Quik-like stains for the simultaneous evaluation of human sperm morphology and chromatin status.

BACKGROUND Sperm chromatin status and nuclear DNA damage can be detected using well-established assays. However, most techniques are time-consuming and/or involve elaborate protocols and equipment. We have recently developed a simple and fast method to monitor sperm chromatin status in field conditions using the Diff-Quik assay which is employed in fertility clinics to assess sperm morphology with standard bright field microscopy. In the present study, we demonstrate that any Diff-Quik-like stain can easily, reproducibly and routinely monitor human sperm chromatin status as well. METHODS Different Diff-Quik-like stains were used to assess sperm morphology and the presence of abnormal dark nuclear staining in human sperm from four ART centres. The TUNEL assay was performed in the same samples, and fertility outcomes were assessed. RESULTS A significant correlation was found between TUNEL-positive sperm and dark sperm nuclei. Moreover, associations were also found between the percentage of dark sperm nuclei and seminal parameters, embryo development rate, embryo quality and clinical pregnancy, as well as with cryptorchidism, and there was a tendency towards an association with age. A value of 32% abnormal staining is suggested as a predictive threshold for embryo development and pregnancy. CONCLUSIONS Our results show that any Diff-Quik-like stain, already implemented in most laboratories to assess sperm morphology, can be adapted as an indicator for chromatin status in human sperm.
Constancy of distributions: asymptotic efficiency of certain nonparametric tests of constancy

In this paper we study stochastic processes which enable monitoring the possible changes of probability distributions over time. These so-called monitoring processes are bivariate functions of time and position at the measurement scale, and in particular be used to test the null hypothesis of no change: one may then form Kolmogorov--Smirnov or other type of tests as functionals of the processes. In Hjort and Koning (2001) Cram? r-type deviation results were obtained under the constancy null hypothesis for [bootstrapped versions of] such ``derived'' test statistics. Here the behaviour of derived test statistics is investigated under alternatives in the vicinity of the constancy hypothesis. When combined with Cram? r-type deviation results, the results in this paper enable the computation of efficiencies of the corresponding tests. The discussion of some examples of yield guidelines for the choice of the test statistic, and hence for the underlying monitoring process.
Blind separation of skewed signals in instantaneous mixtures

The problem of source separation of instantaneous mixtures has been addressed thoroughly in literature in the past. The assumption of statistical independence between the source signals, led to the introduction of independent component analysis (ICA). A number of methods, based on the ICA framework, can identify nonGaussian sources in instantaneous mixtures with robust convergence and performance. However, in several biomedical applications, there is a need to identify and separate signals that, apart from being nonGaussian, are not symmetric. In this article, the authors present a method for blind identification and separation of skewed (non-symmetric) signals in a linear instantaneous mixture.
Specification and management of QoS in real-time databases supporting imprecise computations

Real-time applications such as e-commerce, flight control, chemical and nuclear control, and telecommunication are becoming increasingly sophisticated in their data needs, resulting in greater demands for real-time data services that are provided by real-time databases. Since the workload of real-time databases cannot be precisely predicted, they can become overloaded and thereby cause temporal violations, resulting in damage or even a catastrophe. Imprecise computation techniques address this problem and allow graceful degradation during overloads. In this paper, we present a framework for QoS specification and management consisting of a model for expressing QoS requirements, an architecture based on feedback control scheduling, and a set of algorithms implementing different policies and behaviors. Our approach gives a robust and controlled behavior of real-time databases, even for transient overloads and with inaccurate runtime estimates of the transactions. Further, performance experiments show that the proposed algorithms outperform a set of baseline algorithms that uses feedback control.
Generalized Orowan‐Petch Plot for Brittle Fracture

The fracture of brittle solids is considered to be based on a defect configuration consisting of a stress concentrator, in our case a hemispherical pore, and a starter crack, in our case either a semicircular crack, a circular crack, or a circumferential crack. Computation of the stress field, application of the relevant weight functions, and an averaging scheme based on the assumption of a virtual crack increment provides stress intensity factors for all defect configurations considered. A normalization scheme yields a generalized version of the Orowan-Petch plot in the form of a normalized strength to normalized defect size relationship.
Parallel analytics as a service

Recently, massively parallel processing relational database systems (MPPDBs) have gained much momentum in the big data analytic market. With the advent of hosted cloud computing, we envision that the offering of MPPDB-as-a-Service (MPPDBaaS) will become attractive for companies having analytical tasks on only hundreds gigabytes to some ten terabytes of data because they can enjoy high-end parallel analytics at a cheap cost. This paper presents Thrifty, a prototype implementation of MPPDB-as-a-service. The major research issue is how to achieve a lower total cost of ownership by consolidating thousands of MPPDB tenants on to a shared hardware infrastructure, with a performance SLA that guarantees the tenants can obtain the query results as if they are executing their queries on dedicated machines. Thrifty achieves the goal by using a tenant-driven design that includes (1) a cluster design that carefully arranges the nodes in the cluster into groups and creates an MPPDB for each group of nodes, (2) a tenant placement that assigns each tenant to several MPPDBs (for high availability service through replication), and (3) a query routing algorithm that routes a tenant's query to the proper MPPDB at run-time. Experiments show that in a MPPDBaaS with 5000 tenants, where each tenant requests 2 to 32 nodes MPPDB to query against 200GB to 3.2TB of data, Thrifty can serve all the tenants with a 99.9% performance SLA guarantee and a high availability replication factor of 3, using only 18.7% of the nodes requested by the tenants.
The Sarbanes-Oxley Act and the changing role of the CIO and IT function

The focus of this study is on the changing role of the Chief Information Officer (CIO). At a time when there is an increasing focus on corporate governance and enterprise risk management, the competencies required of CIOs are evolving causing a shift to a third era of the CIO. This shift is being accelerated and influenced by the passage of the Sarbanes-Oxley Act of 2002 in the USA. This Act mandates detailed reporting of internal controls over financial and related systems, and has consumed the energy and the budgets of the IT function in the past few years. In the coming years, the Act will likely impact the success of CIOs and the competencies desired by organisations hiring CIOs. These issues are explored in detail. The article concludes with an agenda for research on CIOs in this new era.
Prognostic factors related to survival and groin recurrence following therapeutic lymph node dissection for lower limb malignant melanoma

A retrospective analysis was carried out of 133 patients undergoing therapeutic lymph node dissection for malignant melanoma of the lower limb. A radical ilio‐obturator dissection (RID) was performed in 106 patients and a superficial femoral dissection (SFD) in the remaining 27. On univariate analysis five factors were found to be significant indicators of prognosis. These were: Clark level of the primary (P = 0·02); primary melanoma thickness (P = 0·04); total number of positive nodes (P<0·001); number of positive femoral nodes (P < 0·001); and number of positive ilio‐obturator nodes (P<0·001). On multiple regression analysis only the number of positive nodes in each compartment remained a significant independent factor (P<0·001). The morbidity associated with RID was not significantly greater than after SFD. RID was, however, associated with a reduction in subsequent groin recurrence. Radical nodal clearance is the operation of choice. This technique provides maximum prognostic information, reduces the likelihood of local untreatable disease and possibly improves overall survival rates—especially when only one iliac node is involved.