nils-herrmann/clean_scirepeval huggingface dataset:
Plus ça change — a model for stasis and evolution in different environments

The Plus ca change model proposes that morphological stasis is the usual response to widely fluctuating physical environments on geological timescales (until thresholds are reached). The lineages that survive in a more changing environment on geological timescales are those that are relatively inert to each environmental twist and turn, in contrast to more sensitive lineages in less changing environments. Generalists in this long-term sense are species with properties that enable them to survive throughout wide environmental fluctuations over geological timescales; they are thus related to but distinct from ecological eurytopes. The model predicts a tendency for continuous, gradualistic evolution on land in the tropics and in the deep sea, and for more stasis (and occasional punctuations) in shallow waters and temperate zones. As the vast majority of the fossil record comes from dynamic shallow marine environments, it is not surprising that many fossil lineages show approximate stasis and occasional punctuations. Punctuated equilibrium could be being mistakenly perceived as the overwhelming pattern in the history of life because the environments in which gradualism predominates are rarely preserved in the fossil record. The evolutionary pattern in a lineage at a single locality is predicted to be stasis when there is greater environmental fluctuation, and net directional change and/or more widely fluctuating morphologies when environments are more narrowly fluctuating. Given the Quaternary climate upheavals, relatively little evolution may be occurring worldwide at present (except for evolution induced by humans). Such a model is bound to have many exceptions; it is only about tendency and relative frequency. Though few case histories are yet known, many existing data sets probably contain clues that can be used in testing the model. Other relevant aspects of perception are also discussed, including descriptive biases and evolutionary reversals.

Field of study: Environmental science, Geography
Virtual World Security Inspection

Virtual property theft is a serious problem that exists in virtual worlds. Legitimate users of these worlds invest considerable amounts of time, effort and real-world money into obtaining virtual property, but unfortunately, are becoming victims of theft in high numbers. It is reported that there are over 1 billion registered users of virtual worlds containing virtual property items worth an estimated US$50 billion dollars. The problem of virtual property theft is complex, involving many legal, social and technological issues. The software used to access virtual worlds is of great importance as they form the primary interface to these worlds and as such the primary interface to conduct virtual property theft. The security vulnerabilities of virtual world applications have not, to date, been examined. This study aims to use the process of software inspection to discover security vulnerabilities that may exist within virtual world software – vulnerabilities that enable virtual property theft to occur. Analyzing three well know virtual world applications World of Warcraft, Guild Wars and Entropia Universe, this research utilized security analysis tools and scenario testing with focus on authentication, trading, intruder detection and virtual property recovery. It was discovered that all three examples were susceptible to keylogging, mail and direct trade methods were the most likely method for transferring stolen items, intrusion detection is of critical concern to all VWEs tested, stolen items were unable to be recovered in all cases and lastly occurrences of theft were undetectable in all cases. The results gained in this study present the key problem areas which need to be addressed to improve security and reduce the occurrence of virtual property theft.

Field of study: Computer science
Contact Action of Pegmatite on Schist

Pegmatites are normally small and usually occur in the parent igneous rock, so that cases of contact metamorphism directly attributable to pegmatites are rare. In connection with recent studies 2 of the Etta spodumene mine near Keystone, South Dakota, the writers’ attention was attracted by the pronounced contact zone which surrounds this remarkable pegmatite. Several specimens were selected as showing the various phases of the metamorphosed rock and these were analyzed and studied microscopically, with the results noted below. The writers are indebted to Dr. F. F. Grout for suggestions and criticisms, and to Dr. John W. Gruner for additional rock samples, necessary to complete the work. Geologic Setting of the Etta Mine The geology of the Etta mine has been described in some detail in the paper cited above. The pegmatite is one of a great series which radiate outward into pre-Cambrian schists from the Harney Peak granite batholith, . . .

Field of study: Geology
Sustaining Change in Universites: Continuities in Case Studies and Concepts (review)

racism causes people of different races to have distinctly different experiences in the first place. Because Tim Wise does not pretend to offer a balanced argument in Affirmative Action, it might be written off as being too lopsided. Unlike most polemics, however, Wise seriously considers the most recent body of research to stake his positions. For this reason, it is an appropriate university text that will guarantee lively classroom discussions. Both critics and supporters of affirmative action alike will learn something new as well as find something to praise and criticize. But, if you are considering this book for instructional purposes, first ask yourself, “Are you ready to bring it on?”

Field of study: Education
Density Functional Study on A-Units Based on Thieno[3,4-c]pyrrole-4,6-dione for Organic Solar Cells

AbstractThe use of polymer donor materials has allowed great progress in organic solar cells. To search for potential donor materials, we have designed a series of donor–acceptor (D–A)-type alternating polymers composed of dithieno[3,2-b:2′,3′-d]pyrrole (DTP) electron-rich units and thieno[3,4-c]pyrrole-4,6-dione (TPD) electron-deficient units. Their electronic and optical properties have been investigated using density functional theory and Marcus theory. The calculation results demonstrate that introduction of cyclic compounds (furyl, thienyl, and phenyl) into electron-deficient units of the molecules can result in lower highest occupied molecular orbital (HOMO) levels and reorganization energies compared with the experimental molecule (X0). To investigate the effects of electron-withdrawing units, three electron-withdrawing substituents (–OCH3, –F, and –CN) were introduced into the thienyl. The results indicated that the polymer X2–3 will show the best performance among the designed polymers, offering low-lying HOMO energy level (−5.47 eV), narrow energy gap (1.97 eV), and high hole mobility (7.45 × 10−2 cm2 V−1 s−1). This work may provide a guideline for the design of efficient D–A polymers for organic solar cells with enhanced performance.Graphical AbstractDonor–acceptor (D–A) unit polymers have been extensively investigated by researchers as donor materials. However, most such work has focused on donor units, while the work presented herein outlines an effective way to modulate the properties of acceptor units based on thieno[3,4-c]pyrrole-4,6-dione in D–A polymers. The results show that incorporation of a thienyl substituent and bonding –CN (X2–3) as acceptor moiety in D–A-type polymers is an efficient strategy to improve the absorption and mobility (μh = 7.45 × 10−2 cm2 V−1 s−1) and thus enhance the photovoltaic performance (PCE ≈ 5.82%) of organic solar cells.

Field of study: Materials science
SU‐E‐T‐424: Feasibility of 3D Printed Radiological Equivalent Customizable Tissue Like Materials

To investigate the feasibility of 3D printing CT# specific radiological equivalent tissue like materials.  A desktop 3D printer was utilized to create a series of 3 cm x 3 cm x 2 cm PLA plastic blocks of varying fill densities. The fill pattern was selected to be hexagonal . A series of blocks was filled with paraffin and compared to a series filled with air. The blocks were evaluated with a “GE Lightspeed” 16 slice CT scanner and average CT# of the centers of the materials was determined. The attenuation properties of the subsequent blocks were also evaluated through their isocentric irradiation via “TrueBeam” accelerator under six beam energies. Blocks were placed upon plastic-water slabs of 4 cm in thickness assuring electronic equilibrium and data was collected via Sun Nuclear “Edge” diode detector. Relative changes in dose were compared with those predicted by Varian “Eclipse” TPS.  The CT# of 3D printed blocks was found to be a controllable variable. The fill material was able to narrow the range of variability in each sample. The attenuation of the block tracked with the density of the total fill structure. Assigned CT values in the TPS were seen to fall within an expected range predicted by the CT scans of the 3D printed blocks.  We have demonstrated that it is possible to 3D print materials of varying tissue equivalencies, and that these materials have radiological properties that are customizable and predictable.

Field of study: Medicine, Physics
New Gamma Detector Array Finds Evidence of Hyperdeformed Nuclei

How much spin can a nucleus take before centrifugal force pulls it apart? A surprising answer is proffered by one of the first physics results from the Gammasphere facility at the Lawrence Berkeley National Laboratory. Gammasphere is the first of a new generation of nuclear‐physics photon detector arrays. In June the Berkeley, Oak Ridge, Washington University collaboration at Gammasphere published evidence that gadolinium‐147 nuclei might be reaching angular momenta as high as 90ħ without succumbing to fission. “That's embarrassingly high,” says collaboration leader Demetrios Sarantites, “because the theory says that the barrier against fission should vanish at around 80ħ.”

Field of study: Physics
Distribution of the Ratio of the Largest Eigenvalue to the Trace of Complex Wishart Matrices

This correspondence investigates the statistical properties of the ratio <i>T</i> = λ<sub>1</sub>/Σ<sub>i=1</sub><sup>m</sup>λ<i>i</i> , where are λ<sub>1</sub> ≥ λ<sub>2</sub> ≥ ··· ≥ λ<sub>m</sub> the <i>m</i> eigenvalues of an <i>m</i> × <i>m</i> complex central Wishart matrix <b>W</b> with <i>n</i> degrees of freedom. We derive new exact analytical expressions for the probability density function (PDF) and cumulative distribution function (CDF) of <i>T</i> for complex central Wishart matrices with arbitrary dimensions. We also formulate simplified statistics of <i>T</i> for the special case of dual uncorrelated and dual correlated complex central Wishart matrices (<i>m</i> = 2) . The investigated ratio <i>T</i> is the most important ratio in blind spectrum sensing, since it represents a sufficient statistics for the generalized likelihood ratio test (GLRT). Thus, the derived analytical results are used to find the exact decision threshold for the desired probability of false alarm for Blind-GLRT (B-GLRT) detector. It is shown that the exact decision threshold based B-GLRT detector gives superior performance over the asymptotic decision threshold schemes proposed in the literature, which leads to efficient spectrum usage in cognitive radio.

Field of study: Engineering
Rubisco is not really so bad.

Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) is the most widespread carboxylating enzyme in autotrophic organisms. Its kinetic and structural properties have been intensively studied for more than half a century. Yet important aspects of the catalytic mechanism remain poorly understood, especially the oxygenase reaction. Because of its relatively modest turnover rate (a few catalytic events per second) and the competitive inhibition by oxygen, Rubisco is often viewed as an inefficient catalyst for CO2 fixation. Considerable efforts have been devoted to improving its catalytic efficiency, so far without success. In this review, we re-examine Rubisco's catalytic performance by comparison with other chemically related enzymes. We find that Rubisco is not especially slow. Furthermore, considering both the nature and the complexity of the chemical reaction, its kinetic properties are unremarkable. Although not unique to Rubisco, oxygenation is not systematically observed in enolate and enamine forming enzymes and cannot be considered as an inevitable consequence of the mechanism. It is more likely the result of a compromise between chemical and metabolic imperatives. We argue that a better description of Rubisco mechanism is still required to better understand the link between CO2 and O2 reactivity and the rationale of Rubisco diversification and evolution.

Field of study: Environmental science
Inhibitory stimulus control following errorless discrimination learning.

Three generalization procedures were used to investigate inhibitory stimulus control following discrimination learning with few errors. Three groups of pigeons acquired a discrimination between a green stimulus (the positive stimulus) and a vertical or horizontal line (the negative stimulus) through differential autoshaping followed by multiple schedule presentation of the two stimuli with gradually increasing stimulus durations. Genereralization testing was along a line-tilt continuum. For one group, the test involved a resistance-to-reinforcement procedure in which responses to all line tilts were reinforced on a variable-interval schedule. For a second group, also tested with the resistance-to-reinforcement procedure, the lines were superimposed on the green field that formerly served as the positive stimulus. A third group was tested in extinction with the combined stimuli. Control groups had no discrimination training but responding to green was nondifferentially reinforced. The control subjects responded more to all line tilts during testing than did the comparable experimental subjects, indicating that the negative stimulus had become an inhibitory stimulus. Both resistance-to-reinforcement groups revealed inhibitory gradients around the negative stimulus, but the gradient for the extinction group was relatively flat. These data are consistent with others that modify Terrace's early conclusion concerning the failure of inhibition to develop during errorless training.

Field of study: Biology, Psychology
An Efficient Synthesis of an Orthogonally Protected Aromatic Diamine as Scaffold for Tweezer Receptors with Two Different Arms

The synthesis of a new versatile template, 3-(N-Boc-aminomethyl)-5-(N-Fmoc-aminomethyl)benzoic acid (1), was developed and is hereby reported. The key feature of the synthetic strategy is the selective mono reduction of a symmetric diazide using a biphasic reaction mixture. The mono reduction allows the sequential introduction of two orthogonal protecting groups – e.g., Fmoc and Boc. This building block can be used as a scaffold for the solid-phase synthesis of dipodal or cyclic peptidic receptors. It allows the preparation of tweezer receptors with unsymmetrically substituted side arms and therefore for the implementation of an enhanced structural and functional diversity in comparison to symmetric tweezers.

Field of study: Chemistry
Evidence for a Western Extracontinental Land Source During the Devonian Period in the Central Andes

A large intracratonic sedimentary basin of mid-Paleozoic age in the central Andes apparently received sediments from a western land source. Lithofacies and isopach data show a thickening and general textural coarsening to the north and west in the Devonian rocks of Bolivia. Early to early Middle Devonian onlap and offlap are recognized. Rate of subsidence in the basin was only slightly exceeded by rate of sedimentation, because the youngest Devonian beds recognized are either very shallow marine (in southern localities) or nonmarine (in at least one northern locality). Devonian brachiopod community studies suggest that a shallow marine environment persisted in the region throughout the time of deposition of the Devonian rocks. An absence of bedded carbonate rocks indicates a cold-climate environment of deposition. It is suggested that the source area yielded abundant muscovite. Outcrops of sialic basement relicts in the Cordillera Occidental are concluded to be portions of a buried land mass.

Field of study: Geology
Rights and Security in Housing: the repossession process in the social rented sector

Rented housing in Britain is divided between a private sector in which houses are let for profit, and a social rented sector in which houses have traditionally been let as a service to the community. The social rented sector is itself divided between two main types of provider: local authorities (council housing), and housing associations, although account must be taken of other providers, particularly in Scotland, where Scottish Homes, a quango, is a substantial provider of social housing. Until recently, the new towns were substantial providers of rented housing, but the new town development corporations have now all been wound up and their stock transferred to other landlords. In this article, the expressions 'social rented sector' and 'social housing' refer to housing let by the public sector bodies just referred to and by housing associations. For most of this century the nature of the provider has determined the legal tenure on which rented housing has been held. Thus, the Rent Acts applied to private sector lets, but were not applied to public sector tenants. Between 1980 and 1989 council tenants and housing association tenants shared a common tenure regime, the secure tenancy. However, when in 1989, a new form of tenure the assured tenancy was introduced for the private sector,' it was also applied to new housing association lets, although local authorities and other public sector bodies continued to offer secure tenancies. As a consequence, since 1989, there have been two different legal tenures within the social rented sector: the secure tenancy and the assured tenancy. The two legal regimes afford substantially different rights to tenants. In the light of these changes to tenure regimes, this article discusses the importance of legal guarantees of security of tenure in the social rented sector, and compares the way in which the process of recovery of possession has been operating in the two forms of tenure. This is a two-fold comparison. As the rights of existing housing association tenants were preserved in 1989, housing associations continued to have many secure tenants, and so it is possible to compare the respective positions of secure and assured tenants both (a) as between local authorities and housing associations, and (b) within the housing association sector. The research on which this article is based shows that there are substantial differences in the outcomes of the repossession process for different groups of tenants. The questions these outcomes pose include whether differences in the legal rights of secure and assured tenants are capable of explaining the outcomes of the repossession process, and what other factors might be influencing outcomes.

Field of study: Law
Machine Learning Assisted Differential Distinguishers For Lightweight Ciphers

At CRYPTO 2019, Gohr first introduces the deep learning based cryptanalysis on round-reduced SPECK. Using a deep residual network, Gohr trains several neural network based distinguishers on 8-round SPECK-32/64. The analysis follows an ‘all-in-one’ differential cryptanalysis approach, which considers all the output differences effect under the same input difference. Usually, the all-in-one differential cryptanalysis is more effective compared to the one using only one single differential trail. However, when the cipher is non-Markov or its block size is large, it is usually very hard to fully compute. Inspired by Gohr's work, we try to simulate the all-in-one differentials for non-Markov ciphers through machine learning. Our idea here is to reduce a distinguishing problem to a classification problem, so that it can be efficiently managed by machine learning. As a proof of concept, we show several distinguishers for four high profile ciphers, each of which works with trivial complexity. In particular, we show differential distinguishers for 8-round Gimli-Hash, Gimli-Cipher and Gimli-Permutation; 3-round Ascon-Permutation; 10-round Knot-256 permutation and 12-round Knot-512 permutation; and 4-round Chaskey-Permutation. Finally, we explore more on choosing an efficient machine learning model and observe that only a three layer neural network can be used. Our analysis shows the attacker is able to reduce the complexity of finding distinguishers by using machine learning techniques.

Field of study: Computer science, Mathematics
Effects of different angles on the growth stress, wood density and wood shrinkage of the reaction wood.

In this paper,we select the 3-year-old pine seedlings and the 1-year-old poplar cuttings for plantation from artificial forest of Anhui Agricultural University(Both the number of poplars and pines are 60.There are 5 groups and 5 angles 0°,15°,30°,45°and 60°.Each group contains 12 and corresponds to a angle)to determinate the growth stress indicator,(GSI is called for short)wood density and wood shrinkage for researching.The results show that:(1)There is a significant positive correlation between the GSI absolute size of poplars and pines and the angle.(2)There is a significant positive correlation between the basic density of poplars and pines and the angle.(3)The relationship between the radial shrinkage rate of poplars and pines and the angle is not significant.There is a positive correlation between the axial shrinkage rate of poplars and pines and the angle.The correlation between the tangential shrinkage rate of poplars and the angle is positive,and the pine shows a negative correlation.(4)The poplar tangential shrinkage is larger in tension wood area than that in opposite wood area,and the change of poplar radial shrinkage is not much.Both the pine tangential shrinkage and radial shrinkage are less in compression wood area than that in opposite wood area.The axial shrinkage is much larger in reaction wood area than that in opposite wood area.

Field of study: Agricultural and Food sciences
Compound semiconductor activation energy in humidity

Product reliability investigations typically include accelerated humidity testing. Originally, the “standard” test was a biased 85 °C/85% relative humidity (RH) lifetest for 1000 h. Recently, a substitute accelerated version of this test has been used. The accelerated version is called highly accelerated stress test (HAST). The HAST conditions are also biased, at 130 °C, 85%RH, and approximately 18 PSI overpressure. The duration of the HAST test is normally 96–100 h – to be equivalent to the 85/85 test. This study is intended to investigate thermal acceleration and show that equivalent HAST tests on compound semiconductors are more highly accelerated and could be conducted with much shorter durations.

Field of study: Engineering
Crystallization and preliminary X-ray analysis of recombinant full-length human m-calpain.

m-Calpain constitutes the prototype of the superfamily of neutral calcium-activated cysteine proteinases. It is a heterodimer consisting of an 80 and a 30 kDa subunit. Recombinant full-length human m-calpain has been crystallized using macro-seeding techniques and vapour-diffusion methods. Two different monoclinic crystal forms (space group P2(1)) were obtained from a solution containing polyethylene glycol (M(W) = 10 000) as a precipitating agent. Complete data sets have been collected to 2.3 and 3.0 A resolution using cryo-cooling conditions and synchrotron radiation. The unit-cell parameters are a = 64.86, b = 133.97, c = 78.00 A, beta = 102.43 degrees and a = 51.80, b = 171.36, c = 64.66 A, beta = 94.78 degrees, respectively. The V(m) values indicate that there is one heterodimer in each asymmetric unit.

Field of study: Chemistry