Miracle-dz/UniFAR-FTUs huggingface dataset:
On Nonlinear Compensation Techniques for Coherent Fiber-Optical Channel

Fiber-optical communication systems form the backbone of the internet, enabling global broadband data services. Over the past decades, the demand for high-speed communications has grown exponentially. One of the key techniques for the efficient use of existing bandwidth is the use of higher order modulation formats along with coherent detection. However, moving to high-order constellations requires higher input power, and thus leads to increased nonlinear effects in the fiber. In long-haul optical communications (distances spanning from a hundred to a few thousands of kilometers), amplification of the signal is typically needed as the fibers exhibit power losses. Amplifiers add noise and the signal and noise interact, leading to nonlinear signal–noise interactions, which degrade the system performance. The propagation of light in an optical fiber is described by the nonlinear Schrodinger equation (NLSE). Due to the lack of analytical solutions for the NLSE, deriving statistics of this nonlinear channel is in general cumbersome. The state-of-the-art receiver for combating the impairments existing in a fiber-optical link is digital backpropagation (DBP), which inverts the NLSE, and is widely believed to be optimal. Following this optimality, DBP has enabled system designers to determine optimal transmission parameters and provides a benchmark against which other detectors are compared. However, a number of open questions remain: How is DBP affected by noise? With respect to which criterion is DBP optimal? Can we estimate the optimal transmit power for a system when DBP is used? In paper A, starting from basic principles in Bayesian decision theory, we consider the well-known maximum a posteriori (MAP) decision rule, a natural optimality criterion which minimizes the error probability. As the closed-form expressions required for MAP detection are not tractable for coherent optical transmission, we employ the framework of factor graphs and the sum-product algorithm, which allow a numerical evaluation of the MAP detector. The detector turns out to have similarities with DBP (which can be interpreted as a special case) and is termed stochastic digital backpropagation, as it accounts for noise, as well as nonlinear and dispersive effects. Through Monte Carlo simulations of a single-channel communication system, we see significant performance gains with respect to DBP for dispersion-managed links. In paper B, we investigate the performance limits of DBP for a non dispersion-managed fiber-optical link. An analytical expression is derived that can be used to find the optimal transmit power for a system when DBP is used. We found that a first-order approximation is reasonably tight for different symbol rates and it can be used to approximately compute the optimum transmit power in terms of minimizing the symbol error rate. Moreover, the first-order approximation results show that the variance of the nonlinear noise grows quadratically with transmitted power, which limits the performance of a system with DBP.
Machine Learning Technique Based Annotation in Web Database Search Result Records with Aid of Modified K-Means Clustering (MKMC)

To reduce the memory usage and increase the speed of access in web database, in this study, we have introduced a machine learning technique based annotation with the help of modified K-means clustering algorithm to increase the speed of search result records in web database. The proposed AI based annotation method includes four stages namely, alignment phase, Score Calculation, annotation phase and annotation wrapper generation phase. These four stages of the proposed part are spelt out in this study. The proposed technique is competent to effectively reduce the memory and increase the speed of access in a website. The proposed method is implemented in the working platform of java and the results are analyzed.
Red giant masses and ages derived from carbon and nitrogen abundances

We show that the masses of red giant stars can be well predicted from their photospheric carbon and nitrogen abundances, in conjunction with their spectroscopic stellar labels log g, Teff, and [Fe/H]. This is qualitatively expected from mass-dependent post-main-sequence evolution. We here establish an empirical relation between these quantities by drawing on 1475 red giants with asteroseismic mass estimates from Kepler that also have spectroscopic labels from Apache Point Observatory Galactic Evolution Experiment (APOGEE) DR12. We assess the accuracy of our model, and find that it predicts stellar masses with fractional rms errors of about 14 per cent (typically 0.2 M⊙). From these masses, we derive ages with rms errors of 40 per cent. This empirical model allows us for the first time to make age determinations (in the range 1–13 Gyr) for vast numbers of giant stars across the Galaxy. We apply our model to ∼52 000 stars in APOGEE DR12, for which no direct mass and age information was previously available. We find that these estimates highlight the vertical age structure of the Milky Way disc, and that the relation of age with [α/M] and metallicity is broadly consistent with established expectations based on detailed studies of the solar neighbourhood.
CRUD Operations in MongoDB

In this paper we will examine the key features of the database management system MongoDB. We will focus on the basic operations of CRUD and indexes. For our example we will create two databases one using MySQL and one in MongoDB. We will also compare the way that data will be created, selected, inserted and deleted in both databases. For the index part we will talk about the different types used in MongoDB comparing them with the indexes used in a relational database. Index Terms - MongoDB, NoSQL, BSON, CRUD, index. I. Introduction MongoDB is a high performance and very scalable document-oriented database developed in C++ that stores data in a BSON format, a dynamic schema document structured like JSON. Mongo hits a sweet spot between the powerful query ability of a relational database and the distributed nature of other databases like Riak or HBase (1). MongoDB was developed keeping in mind the use of the database in a distributed architecture, more specifically a Shared Nothing Architecture, and that is way it can horizontally scale and it supports Master-Slave replication and Sharding. MongoDB uses BSON to store its documents. BSON keep documents in an ordered list of elements, every elements has three components: a field name, a data type and a value. BSON was designed to be efficient in storage space and scan speed which is done for large elements in a BSON document by a prefixed with a length field. All documents must be serialized to BSON before being sent to MongoDB; they're later deserialized from BSON by the driver into the language's native document representation (2).
A Clutter Suppression Method Based on Improved Principal Component Selection Rule for Ground Penetrating Radar

Principal component analysis is usually used for clutter suppression of ground penetrating radar, but its performance is influenced by the selection of main components of target signal. In the paper, an improved principal component selection rule is proposed for selecting the main components of target signal. In the method, firstly difference spectrum of singular value is used to extract direct wave and strong target signal, and then, Fuzzy-C means clustering algorithm is used to determine the weights of principal component of weak target signal. Finally, the principal components of strong target signal and weak target signal are reconstructed to obtain target signal. Experimental results show that the proposed method can effectively remove the clutter signals and reserve more target information.
Engel Curves, Spatial Variation in Prices and Demand for Commodities in Côte D'Ivoire

This paper aims to estimate the price and income elasticities of the demand for essential commodities in Cote d'Ivoire. Using data from the 2002 Cote d'Ivoire Living Standard Survey and a theoretical framework developed by Crawford et al. (2003), we analyse price effects on the demand for groups of commodities by exploiting a relationship between unit values and commodity quantities and deriving Engel curves. Our findings reveal that the own-price elasticity of meat and dairy products is considerably stronger for rich households (those in the 90th percentile of total expenditure) than for poor households (those in the 10th percentile of total expenditure). Although all the modelled groups of commodities are normal goods, the paper shows that starch is more of a necessity for poor households than for rich ones, whereas meat and dairy products are more of a luxury good for poor households than for rich households.
ConEx Performance Evaluation and Application to Video Streaming

With Internet traffic ever increasing, network congestion should occur more and more frequently. During congestion periods, some users contribute more than others to the congestion in the network. It might be interesting for a network operator to differentiate between users proportionally to the congestion they induce, but the necessary information for this purpose is not available at the network layer, and is exchanged at the transport layer (e.g., Transmission Control Protocol (TCP) acks). This led the Internet Engineering Task Force (IETF) to design Congestion Exposure (ConEx), a new mechanism to expose to the network the amount of congestion a user is responsible for, allowing the network operator to improve the fairness between users. ConEx is designed to limit the added complexity, leveraging already existing mechanisms such as Random Early Detection (RED) and Explicit Congestion Notification (ECN), plus a number of modifications to the senders and receivers to be fully operational. Nonetheless, ConEx can also be deployed in a simplified mode of operation, relying only on loss information in DropTail queues to estimate congestion. The objective of this paper is to provide an in depth evaluation of ConEx mechanism. Firstly, we investigate how the setting of ConEx parameters (e.g., congestion policer) and the network configuration (e.g., router queuing, network delay, etc.,) impact the behavior of ConEx and influence its ability to improve fairness between users. Secondly, we compare the level of performance, in terms of fairness improvement, provided by different variants of ConEx of increasing complexity, i.e., from a simple implementation with modifications limited to the sender to a “full” ConEx approach implementing all proposed features. We show that, despite a reduced accuracy in congestion estimation, a simple variant of ConEx is already able to provide a good fairness improvement between users. This is particularly interesting in the context of an initial deployment scenario, allowing an incremental deployment of ConEx. Thirdly, we investigate and discuss the limitations and weaknesses presented by ConEx with regard to short-lived flows. Finally, based on a YouTube traffic model, we illustrate how ConEx can help to enhance the Quality of Experience (QoE) of video streaming users during congestion periods, significantly reducing the number and duration of stalling events. Keywords-ConEx; Performance; ECN; Congestion; Policing; YouTube; LEDBAT.
Design and Evaluation of Temporal Summarization Systems

Temporal Summarization (TS) is a new track introduced as part of the Text REtrieval Conference (TREC) in 2013. This track aims to develop systems which can return important updates related to an event over time. In TREC 2013, the TS track specifically used disaster related events such as earthquake, hurricane, bombing, etc. This thesis mainly focuses on building an effective TS system by using a combination of Information Retrieval techniques. The developed TS system returns updates related to disaster related events in a timely manner. By participating in TREC 2013 and with experiments conducted after TREC, we examine the effectiveness of techniques such as distributional similarity for term expansion, which can be employed in building TS systems. Also, this thesis describes the effectiveness of other techniques such as stemming, adaptive sentence selection over time and de-duplication in our system, by comparing it with other baseline systems. The second part of the thesis examines the current methodology used for evaluating TS systems. We propose a modified evaluation method which could reduce the manual effort of assessors, and also correlates well with the official track’s evaluation. We also propose a supervised learning based evaluation method, which correlates well with the official track’s evaluation of systems and could save the assessor’s time by as much as 80%.
Università degli Studi di Parma DOTTORATO DI RICERCA IN SCIENZE MEDICO-VETERINARIE-CICLO XXVIII-NOVEL MICROBICIDAL AGENTS DERIVED FROM Naja atra CARDIOTOXIN 1 ( CTX-1 )

7 Introduction: . 9 Chapter 1: Antimicrobial peptides (AMPs) . 13 1.1 – Peptide Characteristics . 13 1.2 – Classification of AMPs . 14 1.3 – α-helical AMPs . 15 1.3. 1 – Length. 16 1.3. 2 – Sequence. 16 1.3. 3 – Charge . 16 1.3. 4 – Helicity . 17 1.3. 5 – Hydrophobicity. 17 1.3. 6 – Amphipathicity and hydrophobic moment . 18 1.3. 7 – Angle subtended by the hydrophilic/hydrophobic faces on the wheel projection18 1.3. 8 – Self-association . 18 1.4 – Mechanisms of action . 19 1.4. 1 – “Barrel stave” model . 20 1.4. 2 – “Toroidal-pore” model . 23 1.4. 3 – Detergent-like “carpet” model . 24 1.5 – Animal α-helical peptides . 24 1.5. 1 – α-helical AMPs from invertebrates . 25 1.5. 2 α-helical AMPs from fish. 26 1.5. 3 α-helical AMPs from amphibians . 27 1.5. 4 α-helical AMPs from amniotes . 28
Are Economics-Based and Psychology-Based Measures of Ability the Same?

Economists rely on psychology-based IQ and achievement test scores to assess ability. Yet human capital models of lifetime earnings propagation entail human capital production function parameters that incorporate ability parameters. This paper makes use of human capital theory to derive a highly nonlinear, but empirically tractable, earnings function which when estimated yields parameters representing cognitive ability. Given that the National Longitudinal Survey (NLS-Y) now has up to 22 years of data on each individual respondent, we estimate these earnings functions for each individual to extract individual-specific estimates of ability. We then compare our estimated ability parameters with independently obtained intelligence test scores for these same individuals in the NLS-Y data. We find a significant positive correlation between our measures and the independently obtained psychologically-based cognitive test scores. These measures adhere to predicted relationships regarding types of ability and schooling. We find a positive correlation between intellectual prowess (the ability to create new human capital from old) and years of school, and a negative relation between years of school and stocks of knowledge, as predicted by human capital theory. However, unlike the psychology-based measures, our ability estimates yield a weaker relationship with race, thereby implying the possibility of greater racial biases in the psychologicallybased measures than our economics-based measures. * This paper was partly written while Polachek was a Visiting Scholar at the NBER in Cambridge, Massachusetts. It was presented at the 2011 IZA Cognitive and Non-Cognitive Skills Workshop in Bonn, Germany. We thank Vikesh Amin, Christian Belzil, Armin Falk, Richard Freeman, Claudia Goldin, James Heckman, Daniel Henderson, Larry Katz, Gerald Marschke, Dennis Pixton, Arnab Roy, David Schaffer, Xiangin Xu, and Bong Joon Yoon for valuable advice and discussion.
GEMS: A Revolutionary System for Environmental Monitoring

This paper describes a revolutionary, new observing system designed for environmental monitoring that will integrate MicroElectroMechanicalSystems (MEMS) and nanotechnologies. The concept, known as Global Environmental MEMS Sensors (GEMS), features an integrated system of airborne probes that will remain suspended in the atmosphere for hours to days and take measurements as they are carried by wind currents. Previous efforts focused on defining the major feasibility issues associated with system design and development in the decadal time frame. The current 2-year project focuses on studying the major feasibility issues including costs/benefits and developing a technology roadmap.
Putative Association of ITGB1 Haplotype with the Clearance of HBV Infection

Integrins are transmembrane receptor proteins that mediate cell-cell adhesion and cell-extracellular matrix (ECM) adhesion. The deregulation of cell-ECM adhesion and the abnormal expression of beta1 (β1) integrins (ITGB1 s) are involved in tumor development and metastasis. In the liver, the expression of integrins and ECM proteins can be a cause of hepatocellular carcinoma (HCC) development. We performed direct DNA sequencing of 24 individuals, and identified 23 sequence variants of ITGB1 polymorphisms. Among these 23 variants, 7 common variants were selected based on frequencies and linkage disequilibrium, and then genotyped in a larger-scale group of subjects (n=1,103). The genetic associations of ITGB1 polymorphisms with the clearance of HBV and HCC outcome of HBV patients were analyzed using logistic regression models and Cox relative hazard models. Although there was no significant association observed between the polymorphisms and the HCC outcome of HBV patients, the second most common haplotype (ITGB1 haplotype-2 [C-C-C-C-T-C-T ]) was putatively associated with HBV clearance (OR=0.75, p=0.008 and P corr =0.05). The minor allele frequency (MAF) of ITGB1 haplotype-2 of the spontaneously recovered (SR) group was significantly higher than that of the chronic carrier group (CC) (freq. = 0.248 vs. 0.199). The information derived from this study could be valuable for understanding the genetic factors involved in the clearance of HBV.
MicroReview Expression , secretion and antigenic variation of bacterial Slayer proteins

The function of the S-layer, a regularly arranged structure on the outside of numerous bacteria, appears to be different for bacteria living in different environments. Almost no similarity exists between the primary sequences of S-proteins, although their amino acid composition is comparable. S-protein production is directed by single or multiple promoters in front of the S-protein gene, yielding stable mRNAs. Most bacteria secrete S-proteins via the general secretory pathway (GSP). Translocation of S-protein across the outer membrane of Gram-negative bacteria sometimes occurs by S-protein-specific branches of the GSP. O-polysaccharide side-chains of the lipopolysaccharide component of the cell wall of Gramnegative bacteria appear to function as receptors for attachment of the S-layer. Silent S-protein genes have been found in Campylo-bacter fetus and Lactobacillus acidophilus . These silent genes are placed in the expression site in a fraction of the bacterial population via inversion of a chromosomal segment.
A review on the efficiency of graphene-based BHJ organic solar cells

Graphene, a material composed of one-atom-thick planar sheets of sp2-bonded carbon atoms with a two-dimensional honeycomb structure, has been proposed for many applications due to its remarkable electronic, optical, thermal, and mechanical properties. Its high transparency, conductivity, flexibility, and abundance make it an excellent material to be applied in the field of organic photovoltaic cells, especially as a replacement for transparent conducting oxide electrodes. However, graphene has been demonstrated to be useful not only as substitute for indium tin oxide electrodes, but also as cathode, electron acceptor, hole transport, and electron extraction material. Thus, in this work, we summarize and discuss the efficiency of bulk heterojunction devices using graphene as a main constituent.
Community structure of insect herbivores on introduced and native Solidago plants in Japan

We compared community composition, density, and species richness of herbivorous insects on the introduced plant Solidago altissima L. (Asteraceae) and the related native species Solidago virgaurea L. in Japan. We found large differences in community composition on the two Solidago species. Five hemipteran sap feeders were found only on S. altissima. Two of them, the aphid Uroleucon nigrotuberculatum Olive (Hemiptera: Aphididae) and the scale insect Parasaissetia nigra Nietner (Hemiptera: Coccidae), were exotic species, accounting for 62% of the total individuals on S. altissima. These exotic sap feeders mostly determined the difference of community composition on the two plant species. In contrast, the herbivore community on S. virgaurea consisted predominately of five native insects: two lepidopteran leaf chewers and three dipteran leaf miners. Overall species richness did not differ between the plants because the increased species richness of sap feeders was offset by the decreased richness of leaf chewers and leaf miners on S. altissima. The overall density of herbivorous insects was higher on S. altissima than on S. virgaurea, because of the high density of the two exotic sap feeding species on S. altissima. We discuss the importance of analyzing community composition in terms of feeding guilds of insect herbivores for understanding how communities of insect herbivores are organized on introduced plants in novel habitats.
Direct Determination of Arsenic in Sugar by GFAAS With Transversely Heated Graphite Atomizer and Longitudinal Zeeman-Effect Background Correction

A method has been developed for the direct determination of As in sugar by graphite furnace atomic absorption spectrometry with a transversely heated graphite atomizer (end-capped THGA) and longitudinal Zeeman-effect background correction. The thermal behavior of As during the pyrolysis and atomization steps was investigated in sugar solutions containing 0.2% (v/v) HNO 3 using Pd, Ni, and a mixture of Pd + Mg as the chemical modifiers. For a 60-μL sugar solution, an aliquot of 8% (m/v) in 0.2% (v/v)HNO 3 was dispensed into a pre-heated graphite tube at 70°C. Linear analytical curves were obtained in the 0.25 - 1.50-μg L -1 As range. Using 5 μg Pd and a first pyrolysis step at 600°C assisted by air during 40 s, the formation of a large amount of carbonaceous residue inside the atomizer was avoided. The characteristic mass was calculated as 24 pg As and the lifetime of the graphite tube was around 280 firings. The limit of detection (L.O.D.) based on integrated absorbance was 0.08 μg L -1 (4.8 pg As) and the typical relative standard deviation (n = 12) was 7% for a sugar solution containing 0.5 μg L -1 . Recoveries of As added to sugar samples varied from 86 to 98%. The accuracy was checked in the direct analysis of eight sugar samples. A paired t-test showed that the results were in agreement at the 95% confidence level with those obtained for acid-digested sugar samples by GFAAS.
Oxidative response of green gram seeds under salinity stress

Green gram (Vigna radiata (L.) Wilczek cv. K 851) seeds given a NaCl salinity stress treatment from the onset of germination showed an increasing oxidative response. An increase in proline content was observed in both root and shoot tissues. With an increase in NaCl concentration, electrolyte leakage and lipid peroxidation increased noticeably in both root and shoot. An uniform increase in total peroxide content was recorded with a concomitant increase in the activity of antioxidative enzymes like catalase, guaiacol peroxidase and superoxide dismutase in both root and shoot tissues under salinity stress.