Miracle-dz/UniFAR-FTUs huggingface dataset:
The role of transgenic mouse models in carcinogen identification.

In this article, we examine existing data on the use of transgenic mouse models for identification of human carcinogens. We focus on the three most extensively studied of these mice, Trp53+/-, Tg/AC, and RasH2, and compare their performance with the traditional 2-year rodent bioassay. Data on 99 chemicals were evaluated. Using the International Agency for Research on Cancer/Report on Carcinogens determinations for the carcinogenicity of these chemicals to humans as the standard for comparison, we evaluated a variety of potential testing strategies ranging from individual transgenic models to combinations of these three models with each other and with traditional rodent assays. The individual transgenic models made the "correct" determinations (positive for carcinogens; negative for noncarcinogens) for 74-81% of the chemicals, with an increase to as much as 83% using combined strategies (e.g., Trp53+/- for genotoxic chemicals and RasH2 for all chemicals). For comparison, identical analysis of chemicals in this data set that were tested in the 2-year, two-species rodent bioassay yielded correct determinations for 69% of the chemicals. However, although the transgenic models had a high percentage of correct determinations, they did miss a number of known or probable human carcinogens, whereas the bioassay missed none of these chemicals. Therefore, we also evaluated mixed strategies using transgenic models and the rat bioassay. These strategies yielded approximately 85% correct determinations, missed no carcinogens, and cut the number of positive determinations for human noncarcinogens in half. Overall, the transgenic models performed well, but important issues of validation and standardization need further attention to permit their regulatory acceptance and use in human risk assessment.
Speci fi cation Testing for Functional Forms in Dynamic Panel Data Models

The most popular econometric models in the panel data literature are the class of linear panel data models with unobserved individualand/or time-specific effects. The consistency of parameter estimators and the validity of their economic interpretations as marginal effects crucially depend on the correct functional form specification of the linear panel data model. Based on an individual-specific generalized spectral derivative approach, a new class of residual-based tests is proposed for functional form specification of dynamic panel data models with both large cross-sectional units and time series dimensions. Panel data models can have one-way or two-way error components, individual and time effects can be fixed or random, and panel data can be balanced or unbalanced. The tests can detect a wide range of model misspecifications in the conditional mean of a dynamic panel data model, including functional form and lag misspecification. No common alternative is assumed, thus allowing heterogeneity in the degrees and directions of functional form misspecification across individuals. Moreover, the proposed tests are robust to conditional heteroskedasticity and higher order time-varying conditional moments of unknown form. They check a large number of lags so that they can capture misspecification at any lag order asymptotically. The large number of lag orders does not cause loss of degrees of freedom because the proposed tests naturally discount higher order lags, which is consistent with the stylized fact that economic behaviors are more affected by recent past events than by remote past events. No specific estimation method for dynamic panel data models is required, and the tests have an appealing “nuisance parameter free” property that parameter estimation uncertainty has no impact on the asymptotic distribution of the test statistics. The asymptotic theory developed is the joint asymptotics for degenerate U -statistics, which provides an alternative approach to the existing joint limit approaches in the panel data literature. Thanks to the use of panel data with both large N and T, the proposed nonparametric tests have an asymptotic normal distribution under the null hypothesis without requiring the smoothing parameters to grow with the sample sizes, which suggests better nonparametric asymptotic approximation for panel data than for time series or cross sectional data. This is confirmed in a simulation study. The proposed tests have omnibus power against a variety of alternatives.
Learning from collective experience : successful small farmer associations in northeast Brazil

Both governments and intemational donors have long used farmer associations as a way of promoting rural development and directing benefits to the rural poor in developing countries. Although this remains still as a popular policy, the literature stresses that farmer associations often do not work well. The majority of this literature tends to emphasize this fact rather than analyzing situations in which this policy has been successful. This thesis, therefore, focuses not on the problems of farmer associations, but on what, how, and why a set of three small farmer associations in the state of Ceara in Northeast Brazil did well. Located in the poorest region of the country, all these farmer associations received major funding from government programs. But in contrast to what happens in Ceard and elsewhere, the poor members in the three associations discussed dominated in decision-making. The poor farmers received significant benefits in the form of services, and the associations were able to recover part of the costs of the services they provided. In addition, one association was successful in agricultural production. The analysis of this case study concludes providing lessons for agricultural policy, and for program design and implementation. Thesis supervisor: Judith Tendler Professor of Political Economy
α-MSH regulates intergenic splicing of MC1R and TUBB3 in human melanocytes

Alternative splicing enables higher eukaryotes to increase their repertoire of proteins derived from a restricted number of genes. However, the possibility that functional diversity may also be augmented by splicing between adjacent genes has been largely neglected. Here, we show that the human melanocortin 1 receptor (MC1R) gene, a critical component of the facultative skin pigmentation system, has a highly complex and inefficient poly(A) site which is instrumental in allowing intergenic splicing between this locus and its immediate downstream neighbour tubulin-β-III (TUBB3). These transcripts, which produce two distinct protein isoforms localizing to the plasma membrane and the endoplasmic reticulum, seem to be restricted to humans as no detectable chimeric mRNA could be found in MC1R expressing mouse melanocytes. Significantly, treatment with the MC1R agonist α-MSH or activation of the stress response kinase p38-MAPK, both key molecules associated with ultraviolet radiation dermal insult and subsequent skin tanning, result in a shift in expression from MC1R in favour of chimeric MC1R-TUBB3 isoforms in cultured melanocytes. We propose that these chimeric proteins serve to equip melanocytes with novel cellular phenotypes required as part of the pigmentation response.
Multiplicity and Optical Excess across the Substellar Boundary in Taurus

We present the results of a high-resolution imaging survey of 22 brown dwarfs and very low mass stars in the nearby (~145 pc) young (~1-2 Myr) low-density star-forming region Taurus-Auriga. We obtained images with the Advanced Camera for Surveys High Resolution Channel on HST through the F555W (V), F775W (i′), and F850LP (z′) filters. This survey confirmed the binarity of [BHS98] MHO 8 (hereafter MHO-Tau-8) and discovered a new candidate binary system, [SS94] V410 X-ray 3 (hereafter V410-Xray3), resulting in a binary fraction of 9% at separations >4 AU. Both binary systems are tight (<10 AU), and they possess mass ratios of 0.75 and 0.46, respectively. The binary frequency and separations are consistent with low-mass binary properties in the field, but the mass ratio of V410-Xray3 is among the lowest known. We find that the binary frequency is higher for very low mass stars and high-mass brown dwarfs than for lower mass brown dwarfs, implying either a decline in frequency or a shift to smaller separations for the lowest mass binaries. Combining these results with multiplicity statistics for higher mass Taurus members suggests a gradual decline in binary frequency and separation toward low masses. The implication is that the distinct binary properties of very low-mass systems are set during formation and that the formation process is similar to the process that creates higher mass stellar binaries, but occurs on a smaller scale. We combine the survey detection limits with models for planetary-mass objects to show that there are no planets or very low-mass brown dwarfs with mass >3MJ at projected separation >40 AU orbiting any of the Taurus members in our sample, implying that planetary-mass companions at wide separations are rare. Finally, based on fits to the optical and near-infrared spectral energy distributions, we identify several BDs with significant (≳1 mag) V-band excesses. The excesses appear to be correlated with signatures of accretion and if attributed to accretion luminosity may imply mass accretion rates several orders of magnitude above those inferred from line profile analyses.
Following linguistic footprints: automatic deception detection in online communication

september 2008 | vol. 51 | no. 9 | communications of the acm 119 Deception is information intentionally transmitted to create a false impression or conclusion. Deception in face-to-face communication has been extensively studied in social science disciplines to identify cues to deception and to understand human deception detection. As the globalization and popularity of virtual teams grows, people increasingly rely on computer mediation for interpersonal communication, information acquisition, and information dissemination. Online communication enabled by electronic media (e.g., emails and instant messaging) relieves people from contextual restrictions on their behavior and enables selective self-presentation due to the physical separation and optional anonymity of communication partners. As a result, online communication may offer fertile grounds for deception and alter the social and legal distribution of deceptive practice. According to an annual report of the Internet Crime Complaint Center (IC3, http://www. ic3.gov/), in 2007, IC3 processed about 220,000 complaints that could lead to Internet crime investigations by law enforcement and regulatory agencies. The total dollar loss from all cases of fraud was $239.00 million, up from $198,000 million in 2006. Email was one of the primary mechanisms (73.6%) by which fraudulent contact took place. Despite ample research on deception and on online communication individually, there is relatively little work aiming to understand their interaction until recently. Through a series of studies on deception in online communication, we have obtained a collection of linguistic cues to deception and developed models for automatic deception detection. These cues and models can be used to assist people in detecting online deception and to increase the public awareness of deception in online communication.
Disentangling Spatial Perception and Spatial Memory in the Hippocampus: A Univariate and Multivariate Pattern Analysis fMRI Study

Although the role of the hippocampus in spatial cognition is well accepted, it is unclear whether its involvement is restricted to the mnemonic domain or also extends to perception. We used fMRI to scan neurologically healthy participants during a scene oddity judgment task that placed no explicit demand on long-term memory. Crucially, a surprise recognition test was administered after scanning so that each trial could be categorized not only according to oddity accuracy but also according to subsequent memory. Univariate analyses showed significant hippocampal activity in association with correct oddity judgment, whereas greater parahippocampal place area (PPA) activity was observed during incorrect oddity trials, both irrespective of subsequent recognition performance. Consistent with this, multivariate pattern analyses revealed that a linear support vector machine was able to distinguish correct from incorrect oddity trials on the basis of activity in voxels within the hippocampus or PPA. Although no significant regions of activity were identified by univariate analyses in association with memory performance, a classifier was able to predict subsequent memory using voxels in either the hippocampus or PPA. Our findings are consistent with the idea that the hippocampus is important for processes beyond long-term declarative memory and that this structure may also play a role in complex spatial perception.
Ecology and distribution of silver beech (Nothofagus menziesii) in the Paringa district, South Westland, New Zealand.

The Paringa district is almost completely forested below timberline, with conifer /hardwood forests pre;-ailing in the northeast, and silver beech widely dominant in the southwest, especially at the higher altitudes. In a transitional zone, silver beech grows as scattered stands, isolated by distances up to 6 km. During heavy glaciation of the mountainous part of the district, silver beech may have survived near the present coast and beyond it on land exposed by a lowered sea level. Post-glacial spread from such refugia to the most inland valley heads would require a spreading rate averaging at least 700 m/century, and it is suggested that this was achieved by dispersal of seed on to freshly exposed mineral soils, where beech seedlings apparently can grow independently of mycorrhizal infection. From the nuclei thereby established there was, and still is, gradual invasion of surrounding vegetation. The post-glacial pollen record and the present distribution of silver beech both indicate a pattern of northeasterly spread.
Scientists@Home: What Drives the Quantity and Quality of Online Citizen Science Participation?

Online citizen science offers a low-cost way to strengthen the infrastructure for scientific research and engage members of the public in science. As the sustainability of online citizen science projects depends on volunteers who contribute their skills, time, and energy, the objective of this study is to investigate effects of motivational factors on the quantity and quality of citizen scientists' contribution. Building on the social movement participation model, findings from a longitudinal empirical study in three different citizen science projects reveal that quantity of contribution is determined by collective motives, norm-oriented motives, reputation, and intrinsic motives. Contribution quality, on the other hand, is positively affected only by collective motives and reputation. We discuss implications for research on the motivation for participation in technology-mediated social participation and for the practice of citizen science.
Understanding the 'production' of the schooling identities of young working class boys: time to move beyond the sociological/psychological divide?

In recent times the sociology of childhood has played an important role in challenging the dominance of Piagetian models of child development in shaping the way we think about children and childhood. What such work has successfully achieved is to increase our understanding of the socially constructed nature of childhood; the social competence and agency of children; and the diverse nature of children’s lives, reflecting the very different social contexts within which they are located. One of the problems that has tended to be associated with this work, however, is that in its critique of developmentalism it has tended simply to replace one orthodoxy (psychology) with another (sociology) rather than providing the opportunity to transcend this divide. The purpose of this paper is to demonstrate some of the potential ways in which the sociological/psychological divide might be transcended and the benefits of this for understanding, more fully, the ‘production’ of children’s schooling identities. In particular it shows how some of the key sociological insights to be found in the work of Bourdieu may be usefully extended by the work inspired by the developmental psychologist, Vygotsky. The key arguments are illustrated by reference to ethnographic data relating to the schooling experiences and identities of a group of 5-6 year old working class boys.
“Taming” Bushman farm labour: a villeinous era in neo-feudal Namibia?

This paper examines how “wild” Bushmen became “tame” farm labour in Namibia during a situation where policy encouraged massive white farm settlement while undergoing significant administrative personnel downscaling. Downscaling led to an increase in unrecorded informal violence because farmers were operating in what Moore calls “semi-autonomous fields. ” I suggest that Agamben’s notion of état de siège and Weber’s analysis of villeinage provide useful perspectives for understanding the sociocultural milieu that served to tie down farm labour. Weber and Agamben highlight an ethos of besiegement that had a “looping effect” on legislation, creating a neo-feudal situation. In this besiegement ethos, the spectral presence of those labelled Bushmen provided the seductive master fantasy, the proverbial bogeymen.
ISR meets SAR outside: additive action of the endophyte Bacillus pumilus INR7 and the chemical inducer, benzothiadiazole, on induced resistance against bacterial spot in field-grown pepper

Induced resistance has been recognized as an attractive tool for plant disease management in modern agriculture. During the last two decades, studies on chemically- and biologically elicited induced resistance have revealed previously unknown features of the plant defense response including defense priming. As a biological trigger for induced resistance, plant growth-promoting rhizobacteria (PGPR) are a group of root-associated bacteria that can reduce plant disease severity and incidence, and augment plant growth and yield under greenhouse and field conditions. We evaluated the potential of an endophytic PGPR, Bacillus pumilus INR7, to induce systemic resistance against bacterial spot caused by Xanthomonas axonopodis pv. vesicatoria in pepper. Trials in the greenhouse showed significantly less symptom development in pepper plants inoculated with strain INR7 compared to a water treatment. Furthermore, a single dipping treatment with INR7 before transplantation of pepper plants into the field elicited an induced systemic resistance response against bacterial spot caused by artificially infiltration of X. axonopodis pv. vesicatoria and even against naturally occurring bacterial spot disease. We identified an additive effect on induced resistance after administration of a combination treatment composed of strain INR7 with a chemical inducer, benzothiadiazole (BTH) in the field. The combination treatment stimulated expression of pepper defense marker genes CaPR1, CaTin1, and CaPR4 to a greater extent than did treatment with either agent alone. Similar experiments conducted with tobacco revealed no additive effects under field conditions. Interestingly, co-application of plants with INR7 lifted the growth repressing effect of BTH. Application of BTH onto pepper and tobacco did not affect rhizosphere colonization but supported a higher population density inside plant roots when compared to water-treated control plants. Our results indicate that PGPR can be used in combination with BTH for increased induced resistance capacity under field conditions.
HIV Knowledge, Attitude, and Perception Among University Students

Young people aged between 13 to 29 were contributed to the total of 34% of the cumulative infection Human Immunodeficiency Virus (HIV) in Malaysia. The purpose of this study is to determine the level of knowledge, attitude, and perception among students in the University. Research design is cross-sectional. Questionnaire were distributed to 372 respondents. Therefore, 52.4 percent students had a good knowledge. There was positive weak correlation between KA (r =0.23) and KP (r=0.19) with significance (p<0.05). Conclusion, increase in the level of knowledge were contribute to the positive attitude and perception also reduce the stigma and discrimination toward people living with HIV/AIDS.
pIRS1 and pTRS1 are present in human cytomegalovirus virions

The virus-coded proteins pIRS1 and pTRS1 were found associated with purified human cytomegalovirus virions. The proteins were not degraded when intact virions were treated with trypsin, which suggests that they are localized inside the viral particle. In transfection experiments pIRS1 and pTRS1 modestly activated expression from a reporter plasmid containing the viral major immediate-early promoter but did not influence the activity of a reporter carrying the irs1/trs1 immediate-early promoter. Both reporters were activated by the combination of pIRS1 or pTRS1 and pUL69, which is also present in virions.
Mechanisms for Stable, Robust, and Adaptive Development of Orientation Maps in the Primary Visual Cortex

Development of orientation maps in ferret and cat primary visual cortex (V1) has been shown to be stable, in that the earliest measurable maps are similar in form to the eventual adult map, robust, in that similar maps develop in both dark rearing and in a variety of normal visual environments, and yet adaptive, in that the final map pattern reflects the statistics of the specific visual environment. How can these three properties be reconciled? Using mechanistic models of the development of neural connectivity in V1, we show for the first time that realistic stable, robust, and adaptive map development can be achieved by including two low-level mechanisms originally motivated from single-neuron results. Specifically, contrast-gain control in the retinal ganglion cells and the lateral geniculate nucleus reduces variation in the presynaptic drive due to differences in input patterns, while homeostatic plasticity of V1 neuron excitability reduces the postsynaptic variability in firing rates. Together these two mechanisms, thought to be applicable across sensory systems in general, lead to biological maps that develop stably and robustly, yet adapt to the visual environment. The modeling results suggest that topographic map stability is a natural outcome of low-level processes of adaptation and normalization. The resulting model is more realistic, simpler, and far more robust, and is thus a good starting point for future studies of cortical map development.
Underexposed Video Enhancement via Perception-Driven Progressive Fusion

Underexposed video enhancement aims at revealing hidden details that are barely noticeable in LDR video frames with noise. Previous work typically relies on a single heuristic tone mapping curve to expand the dynamic range, which inevitably leads to uneven exposure and visual artifacts. In this paper, we present a novel approach for underexposed video enhancement using an efficient perception-driven progressive fusion. For an input underexposed video, we first remap each video frame using a series of tentative tone mapping curves to generate an multi-exposure image sequence that contains different exposed versions of the original video frame. Guided by some visual perception quality measures encoding the desirable exposed appearance, we locate all the best exposed regions from multi-exposure image sequences and then integrate them into a well-exposed video in a temporally consistent manner. Finally, we further perform an effective texture-preserving spatio-temporal filtering on this well-exposed video to obtain a high-quality noise-free result. Experimental results have shown that the enhanced video exhibits uniform exposure, brings out noticeable details, preserves temporal coherence, and avoids visual artifacts. Besides, we demonstrate applications of our approach to a set of problems including video dehazing, video denoising and HDR video reconstruction.