Miracle-dz/UniFAR-FTUs huggingface dataset:
Who Are Raising Their Hands? Hand-Raiser Seeking Based on Object Detection and Pose Estimation

In this paper, we propose an automatic hand-raiser recognition algorithm to show who raise their hands in real classroom scenarios, which is of great importance for further an-alyzing the learning states of individuals. To recognize the hand-raisers, we divide the hand-raiser recognition into three subproblems, including hand-raising detection, pose estimation, and matching the raised hands to students. Several challenges exist while dealing with the above-mentioned subproblems, such as low resolution of the back row for keypoints detection, the motion distortion caused by hand raising in pose estimation, and various complex situations for matching. To solve these challenges, we ﬁrst adopt an improved R-FCN algorithm for hand-raising detection, whose eﬀectiveness has been demonstrated. Secondly, we present a novel PAF-based pose estimation algorithm for detecting keypoints of human bodies. The proposed PAF adds scale search and modiﬁed weight metric to adapt to the real and complex scenarios. Speciﬁcally, scale search improves the detection eﬀect at low resolution by pooling human characteristics in diﬀerent sizes of pictures, and modiﬁed weight metric reasonably utilizes the directional vectors of possible limb connections to optimize the case of motion distortion. Thirdly, a heuristic matching strategy based on the location of hand-raising and keypoints information is proposed to recognize the hand-raisers. Experimental results on six teaching videos in real classrooms have demonstrated the eﬃciency of the proposed algorithm, and 83% recognition accuracy indicates the potential applications in real classrooms.
How bright can the brightest neutrino source be

After the discovery of extraterrestrial high-energy neutrinos, the next major goal of neutrino telescopes will be identifying astrophysical objects that produce them. The flux of the brightest source Fmax, however, cannot be probed by studying the diffuse neutrino intensity. We aim at constraining Fmax by adopting a broken power-law flux distribution, a hypothesis supported by observed properties of any generic astrophysical sources. The first estimate of Fmax comes from the fact that we can only observe one universe and, hence, the expected number of sources above Fmax cannot be too small compared with one. For abundant source classes such as starburst galaxies, this one-source constraint yields a value of Fmax that is an order of magnitude lower than the current upper limits from point-source searches. Then we derive upper limits on Fmax assuming that the angular power spectrum is still consistent with neutrino shot noise. We find that the limits obtained with upgoing muon neutrinos in IceCube can already be quite competitive, especially for rare but bright source populations such as blazars. The limits will improve nearly quadratically with exposure and, therefore, be even more powerful for the next generation of neutrino telescopes.
The Design and Evaluation of a User-Centric Information Security Risk Assessment and Response Framework

The risk of sensitive information disclosure and modification through the use of online services has increased considerably and may result in significant damage. As the management and assessment of such risks is a well-known discipline for organizations, it is a challenge for users from the general public. Users have difficulties in using, understanding and reacting to security-related threats. Moreover, users only try to protect themselves from risks salient to them. Motivated by the lack of risk assessment solutions and limited impact of awareness programs tailored for users of the general public, this paper aims to develop a structured approach to help in protecting users from threats and vulnerabilities and, thus, reducing the overall information security risks. By focusing on the user and that different users react differently to the same stimuli, the authors developed a user-centric risk assessment and response framework that assesses and communicates risk on both user and system level in an individualized, timely and continuous way. Three risk assessment models were proposed that depend on user-centric and behavior-related factors when calculating risk. This framework was evaluated using a scenario-based simulation of a number of users and results analyzed. The analysis demonstrated the effectiveness and feasibility of the proposed approach. Encouragingly, this analysis provided an indication that risk can be assessed differently for the same behavior based upon a number of user-centric and behavioral-related factors resulting in an individualized granular risk score/level. This granular risk assessment, provided a more insightful evaluation of both risk and response. The analysis of results was also useful in demonstrating how risk is not the same for all users and how the proposed model is effective in adapting to differences between users offering a novel approach to assessing information security risks.
A new approach to understanding the socio-economic determinants of fertility over the life course

Most theories of fertility predict that a range of socio-economic factors have an impact on the quantum and tempo of childbearing. Despite this, methods often struggle to investigate the interrelationships between these factors, and the time-varying influence that they have on fertility over the life course. In this study, we propose a new approach for studying the socio-economic determinants of fertility. This approach uses the parametric g-formula, which enables analyses of simultaneous and interdependent influences of time-varying socio-economic factors (such as education, employment and partnership) on fertility. Importantly, and unlike many other approaches, this method allows us to incorporate reverse causality and time-varying confounding in a study of total, direct, and indirect (mediating) effects. It also enables these effects to be generalized to a heterogeneous nationally-representative population, linking micro- and macro-level analyses, while avoiding the ecological fallacy. To demonstrate this approach, we study a cohort of women who were born in the UK in 1970. Our results show that a significant reduction in fertility rates would be produced by a reduction in marriage rates, and to a lesser extent by a rise in either education participation or full-time employment immediately after giving birth. For marriage, the majority of this effect is direct, rather than mediated by either education or employment. We conclude our analysis by demonstrating the sensitivity of results to unobserved confounding. We then discuss how our approach can be developed and applied in future research in order to provide researchers with a valuable tool for the analysis of total effects and mediation in studies of correlated life course processes.
Appearance of Negative Differential Conductivity in Graphene Nanoribbons at High-Harmonics

We theoretically study current dynamics of graphene nanoribbons subject to DC-AC driven fields. We show that graphene exhibits negative differential conductivity (NDC) at high-harmonics. NDC occurs in the neighborhood where a constant electric field is equal to amplitude of ac field. We also observe NDC at both even and odd harmonics and at wave mixing of two commensurate frequencies. The even harmonics are more pronounced than the odd harmonics. A possible use of the present method for generating terahertz frequencies at even harmonics in graphene is suggested.
That's How We Roll: An Experiment on Rollover Risk

There is consensus that the recent financial crisis revolved around a crash of the short-term credit market. Yet there is no agreement around the necessary policies to prevent another credit freeze. In this experiment we test the effects that contract length (i.e. maturity mismatch) has on the market-wide supply of short-term credit. Our main result is that, while credit markets with shorter maturities are less prone to freezes, the optimal policy should be state-dependent, favoring long contracts and lower maturity mismatch when the economy is in good shape, and allowing for short-term contracts when the economy is in a recession. We also report the possibility of credit runs on firms with strong fundamentals, something that cannot be observed in the canonical static models of financial panics. Finally, we show that our experimental design produces rich learning dynamics, with a text-book bubble and crash pattern in the market for short-term credit.
Developing Stochastic and Deterministic Models of Quorum Sensing

In recent years, microbiologists have hypothesized that many species of bacteria employ quorum sensing as a communication mechanism, oftentimes to regulate the expression of particular genes. This communication is thought to be facilitated with the aid of signaling molecules called autoinducers which are responsible for regulating transcription in bacteria. Higher concentrations of bacteria produce higher concentrations of autoinducer allowing the bacteria to utilize quorum sensing to sense the density of their own population. In order to precisely understand the underlying process behind quorum sensing, we use quantitative methods. We have developed both deterministic and stochastic methods of analysis to allow for the analysis and investigation of the role of noise during quorum sensing. This paper introduces both a stochastic and deterministic model of quorum sensing in two species of bacteria: Vibrio fischeri and Pseudemonas aeruginosa.
Supply chain management between Finland and China : Empirical evidence from Vaasa region Working Papers

This study is part of the CHISU project. Economic growth has increased rapidly for many decades and China offers a lot of possibilities for both large and small companies. This study focuses on purchasing from China and defining the supply chain between Finland and China. The intention is to help SMEs planning to start collaboration with Chinese suppliers. This study focuses on SMEs in Vaasa region. First, this study reviews Chinese markets and development of its economy. The trade between Finland and China was observed as well. Second, the theoretical part of the study focuses on supply chain and supply chain management. In addition, attention is paid to global supply chain and global purchasing as global purchasing has become a critical strategic decision for companies competing on a global basis. Third, in the empirical part of the study, four case companies were interviewed. The goal was to find out the fluency of the supply chain, how the process has developed and what kinds of problems have occurred. The results of the study show that the main factors affecting the selection of suppliers are price, quality, loyalty, and know-how. In general, companies have been very satisfied to the cooperation with Chinese and the supply chain process has been very fluent. Chinese people are hardworking, friendly and precise, and they really respect their customers. In the future, the interest towards China seems to increase. China is offering a numerous chances, and by benefiting these chances might offer assets and success to the companies. However, creating relationships to China takes a great deal of investments, and it includes risks as well. Anyhow, cooperation may offer both business development potential, and opportunity for learning.
Identi cation and Inference of Jumps using Hedge Fund Returns

Correlated jumps in returns on international equities are infrequent. Therefore, estimating the characteristics of these jumps from time series observations of equity returns is impractical. This paper uses portfolio returns on international equities to generate additional information about the jumpscharacteristics. These portfolio returns are obtained from a group of hedge funds who invest in international equities. Via a model of optimal demand, I exploit the link between the demand of hedge funds for international equities and the characteristics of jumps. On average, hedge funds expect a jump in international equity returns of 15% or larger every 4 years. In contrast, time series observations of international equity returns imply that one of these jumps is expected every 8 years. I am very grateful to Yacine Aït-Sahalia for his invaluable guidance and support. I am also thankful to Dante Amengual, Andrés Aradillas, Markus Brunnermeier, Santiago Garcia, Marco González, Karen Kaiser, Gara M. Afonso, José Scheinkman, Rainer Schwabe, Christopher Sims, Amara Suebsaeng, Wei Xiong, and seminar participants at the Princeton Summer Research Camp and the Civitas Foundation Finance Seminar (Princeton University) for helpful comments and suggestions.
Seasonal changes in the mixed and barrier layers in the western Equatorial Atlantic

Climate is closely related to the dynamics of the surface layer of the tropical Atlantic and the exchange between this latter and the atmosphere, and wearther forecasting will improve with increasing understanding of the processes that govern the relative distribution of thermodynamic properties of the water column. This paper focuses on the isolation of warm surface waters from the cold ones of the deep ocean by a salinity induced barrier layer (BL) in the western equatorial Atlantic (3oS-7oN; 40o-52oW), based on 487 CTD profiles (REVIZEE - 1995-2001). The main process contributing to the seasonal BL formation is the discharge of low salinity waters from the Amazon river. During boreal late winter/spring (Mar-May; high river discharge), deeper isothermal (ZT) and mixed layers (ZM) prevail and the formation of a 16m-thick BL was clearly determined the formation of a salt-induced marked pycnocline within a deeper isothermal layer. However, during the boreal autumn (Oct-Dec; low river discharge), density stratification was mainly determined by temperature distribution (ZM m ZT; BLT = ZM - ZT m 0). There was no clear register of a BL on the Amazon shelf, but a maximum BL (40 m) formed near the shelf break at 45°W.
Visual patterns in the recognition of individuals among chickens

The establishment of a peck-order in the domestic chicken obviously is based on individual recognition, as the flockmates learn to peck their social inferiors and to avoid those to which they are subordinate. Schjelderup-Ebbe (1923) found that when the loppy comb of a hen was turned and fastened to the other side of the head, she was not recognized by the members of her flock. Guhl (1953) reported that dubbed hens were attacked by their inferiors when returned to the pen; and when several hens were dubbed they developed a peck-order, indicating that the comb was not the sole means of individual recognition. The experiment reported here was an attempt to explore further the visible features which affect individual recognition in chickens. Thorpe (1951) reviewed evidences of various types of recognition, such as the perception of mates, of eggs, of other species of birds, and of other individuals within’the flock. He considered it probable that personal recognition by structural and color characteristics is the exception. Auditory clues appear to be important in some species. Armstrong (1947) in his review concluded that deportment in many species appeared to provide the main clues for individual recognition. Various aspects of recognition also were discussed by Nice (1943). Much of the evidence cited in these reviews was taken from reports of general observations rather than from experimental studies. Techniques have been devised for the study of sex recognition by Noble (1936), and Noble and Vogt (1935) ; of predator recognition with the use of models by Nice and Ter Pelkwyk (1941), by Kramer and von St. Paul (1951), and by Hartley (1950); of familial recognition by Cushing and Ramsay (1949) and by Ramsay (1951) ; and of individual recognition by Bennett (1939). Birds which form a social hierarchy, such as chickens, doves, and pigeons, usually attack a strange bird of the same species or breed that is introduced into the pen or cage. An experimentally modified bird which is attacked upon return to its group has been considered as being unrecognized by its penmates. Bennett (1939) altered appeaiantes of ring doves by dyeing the feathers and by modifying contour with feathers glued to the tips of feathers to produce a ruffled appearance. Feathers were plucked in some areas to change contour. She concluded that differences in color or contour are not factors of considerable importance in recognition of individuals in flocks of ring doves. As these birds exhibit peck-dominance rather than peck-right, Bennett found it difficult to determine precisely whether nonrecognition occurred and temporary disturbance of the social order was used as a criterion for loss of recognition. Chickens were used in the present experiment as these birds readily attack a stranger and form a rather stable peck-order based on peck-right. The attention was focused on the visible features which may play a significant role in individual recognition.
Cerebral Ischemia Induced Proteomic Alterations: Consequences for the Synapse and Organelles

Willard J. Costain1, Arsalan S. Haqqani2, Ingrid Rasquinha1, Marie-Soleil Giguere2 and Jacqueline Slinn3 1Glycosyltransferases and Neuroglycomics, Institute for Biological Sciences, National Research Council, Ottawa, ON, 2Proteomics, Institute for Biological Sciences, National Research Council, Ottawa, ON, 3Cerebrovascular Research, Institute for Biological Sciences, National Research Council, Ottawa, ON, Canada
Immune-related genes in gastropods and bivalves: a comparative overview

The biological diversity of molluscs and their adaptation to highly diverse environments offer a unique opportunity for studying the evolution of the innate immune system in invertebrates. This review provides an updated account about the progresses made over the past few years in the study of the molecular players involved in the recognition of pathogen associated molecular patters (PAMPs), in the transduction of immune signaling and in the elimination of potentially pathogenic microbes in gastropod and bivalve molluscs. A major focus will be put on the differences and peculiarities of the molecular immune system of the two major molluscan classes, which have developed specific adaptations to cope with diverse living environments, pathogenic and non- pathogenic microbes over the course of several hundred million years of independent evolution. Intriguing but still poorly understood aspects, such as antiviral response and immune priming, will be also explored, highlighting the present challenges and opportunities connected to the application of modern genomics techniques to the study of the immune system in these fascinating metazoans.
Strong linkages between surface and deep-water dissolved organic matter in the East/Japan Sea

Abstract. Vertical and horizontal distributions of total dissolved amino acids (TDAAs), dissolved organic carbon (DOC), and dissolved organic nitrogen (DON) were measured in the East/Japan Sea (EJS). The euphotic zone of this sea is N-limited, and the N : P ratio is ∼ 13 below 200 m depth. Elevated TDAA concentrations (137 ± 34 nM) and DOC-normalized yields (0.8 ± 0.2 % of DOC) were observed in deep waters ( ≥ 1000 m) of the EJS and compared with those in the deep North Pacific Ocean. Significantly high TDAA concentrations and yields were observed in a region of deep-water formation, indicating the convection of margin-derived bioavailable dissolved organic matter (DOM) to deep waters. Declining TDAA concentrations (36 ± 12 %) and yields (33 ± 13 %) were observed between 1000 and 3000 m throughout the EJS, indicating the utilization of bioavailable DOM in deep waters. Concentrations of the D-enantiomers of amino acids (Ala, Glx, Asx, and Ser) were relatively high in deep waters of the EJS, indicating substantial bacterial contributions to DOM from surface and upper mesopelagic waters. Climate warming during the past few decades in the EJS is weakening deep convection during the winter, and one consequence of this reduction in deep convection is a decline in the supply of bioavailable DOM from surface waters.
Development of Collaborative Autonomous Underwater Systems

This paper provides a description of the development of the Submarine Tracking Interacting Group of Autonomous Intelligent Systems project, also known as STINGRAIS. STINGRAIS has been conceptualized, designed and developed by Team C for the MRSD Project Course 2011-12. The primary objective was to design an autonomous system of mobile underwater robots which could collaboratively search for, detect and track a submarine. The system consists of one Autonomous Underwater Vehicle (AUV), a stationary Underwater Detection System (UDS) and a Ground Control Station (GCS). The UDS and the GCS communicate with each other using a Universal Serial Bus (USB) connection, and the AUV communicates with the GCS using a wireless link. This report gives a detailed description of the full system requirements, functional architecture, physical architecture, and subsystems developed and concludes with the results obtained and lessons learnt by the team over the course of this project.
Population dynamics of southern elephant seals: a synthesis of three decades of demographic research at Marion Island

Southern elephant seal Mirounga leonina numbers declined precipitously throughout most of their circumpolar distribution since the 1950s. A long-term intensive demographic programme was initiated in 1983 on the relatively small population of southern elephant seals at sub-Antarctic Marion Island in an attempt to identify causative mechanisms associated with this decline. Weaned pups have been tagged annually since 1983, and this has produced a large number of individuals of known identity. A regular resighting programme yielded a mark-recapture dataset that has been subjected to numerous survival-based models. This ongoing programme produced a substantial body of scientific literature on population growth patterns, vital rates (survival and fecundity) and population regulation in southern elephant seals, which are reviewed in this synthesis. We briefly describe the analytical framework common to much of the demographic research, highlight important conclusions concerning population regulation of elephant seals at Marion Island, and discuss priorities for future research.
EFFECTS OF SALICYLIC ACID ON THE ANTIOXIDANT ENZYMES ACTIVITY IN SUNFLOWER

The experiment was conducted to determine the effect of salicylic acid (SA) on the antioxidant enzymes activity in sunflower as a randomized complete block design with three replications. Treatments were three levels of salicylic acid including 0, 0.1 and 0.2 g L $1 . Salicylic acid was sprayed twice on sunflower leaves in all treatments except the control before flowering. The last leaves of plants were sampled to determine the activity of catalase, peroxidase, and super oxide dismutase and stored in the laboratory at $80 ◦ C. The results showed that all three enzymes activity increased by SA spraying compared to control. The concentration of 0.2 g L $1 of SA was more effective on these enzymes. Also among the enzymes, peroxidase showed a greater