nils-herrmann/clean_scirepeval huggingface dataset:
AntBot: Anti-pollution peer-to-peer botnets

Botnets have emerged as one of the most severe cyber-threats in recent years. To evade detection and improve resistance against countermeasures, botnets have evolved from the first generation that relies on IRC chat channels to deliver commands to the current generation that uses highly resilient P2P (peer-to-peer) protocols to spread their C&C (Command and Control) information. On an encouraging note, the seminal work done by Holz et al.  showed that P2P botnets, although relieved from the single point of failure that IRC botnets suffer, can be easily disrupted using pollution-based mitigation schemes. For white-hat cyber-security practitioners to be better prepared for potentially destructive P2P botnets, it is necessary for them to understand the strategy space from the attacker's perspective. Against this backdrop, we analyze a new type of P2P botnets, which we call AntBot, that aims to spread their C&C information to individual bots even though an adversary persistently pollutes keys used by seized bots to search the C&C information. The tree-like structure of AntBot, together with the randomness and redundancy in its design, renders it possible that individual bots, when captured, reveal only limited information. We mathematically analyze the performance of AntBot from the perspectives of reachability, resilience to pollution, and scalability. To evaluate the effectiveness of AntBot against pollution-based mitigation in a practical setting, we develop a distributed high-fidelity P2P botnet simulator that uses the actual implementation code of aMule, a popular Kademlia-based P2P client. The simulator offers us a tool to evaluate the attacker's strategy in the cyber space without causing ethical or legal issues, which may result from real-world deployment. Using extensive simulation, we demonstrate that AntBot operates resiliently against pollution-based mitigation. We further suggest a few potential defense schemes that could effectively disrupt AntBot operations and also present challenges that researchers need to address when developing these techniques in practice.

Field of study: Computer science
Testing and Analyzing of Improvement on the Performance of300MW Turbine Unit Before and After Overhaul

According to the testing data of No.2turbine units in XiangFan Power Plant,This paper analyzes the cause of higher running heat rate of the turbine unit before overhaul and makes suggestions on the Overhaul of the tur -bine unit,the improvement on the performance before and after overhaul was analyzed.

Field of study: Engineering, Physics
Two temperature optima of methane production in a typical soil of the Elbe river marshland

The soil of the Elbe river marshland was classified as calcareous freshwater marsh (USDA: typic fluvaquent). Methanogenic bacteria were found in oxic as well as in anoxic soil layers. Most probable number counts varied from 1.4×102 to 2.5×106 bacteria g−1 fresh weight. Methane production at different temperatures (5°C, 10°C, 15°C, 20°C) was studied with undisturbed soil cores. The highest methane production rates were measured at 10°C (0.31 nmol h−1 (g d.w.)−1) and 20°C (0.58 nmol h−1 (g d.w.)−1). Incubation experiments with disturbed soil material showed two optima of methane production at 10°C and in the mesophilic temperature range. Experiments with different substrates indicate that at 10°C acetate serves as substrate while at higher temperatures hydrogen is the main energy source for methanogens.

Field of study: Biology, Environmental science
Proximal Femoral Bone Regeneration After an Uncemented Hydroxyapatite-coated Long-stem in Revision Hip Surgery

Bone remodelling with lateral femoral cortex thinning is a major concern after extensively porous-coated long-stem in revision surgery. Extensive hydroxyapatite coated long-stems were introduced to improve osseointegration, but bone remodelling changes have not been quantified.  The question of whether bone remodelling changes from extensive hydroxyapatite-coated long stems influence the durability of femoral revision, clinical outcome is assessed in follow-up radiographs.  Uncemented straight monoblock hydroxyapatite-coated long-stems used in revision hip surgery for aseptic loosening were assessed in a consecutive series of 64 hips (60 patients). Mean follow-up was 8.6 years and the mean age at surgery was 70 years (27-91). The pre-operative bone defect was classified according to Paprosky. Cortical struts were not used in this series. Cortical index and femoral cortical width were measured at three different levels at different periods.  Four patients with pain under level 4 due to stem loosening needed an exchange surgery of their femoral component, but two patients rejected re-surgery. The cumulative probability of not having aseptic loosening was 91.2% (95% confidence interval 73.5-96.9) at 10 years according to Kaplan and Meier. Twenty-seven of 35 osteolytic lesions had disappeared or decreased at the last follow-up. The thickness of the lateral and medial cortex increased over the course of the study at different levels. Increases of femoral cortex thickness were greater in men and in cases with mild bone defects.  Although clinical outcome of the hydroxyapatite-coated long stem in revision surgery is good but not outstanding, most osteolytic lesions heal and the femoral cortex thickness increases at different levels.

Field of study: Medicine
X-ray radiation damage to biological samples: recent progress.

With the continuing development of beamlines for macromolecular crystallography (MX) over the last few years providing ever higher X-ray flux densities, it has become even more important to be aware of the effects of radiation damage on the resulting structures. Nine papers in this issue cover a range of aspects related to the physics and chemistry of the manifestations of this damage, as observed in both MX and small-angle X-ray scattering (SAXS) on crystals, solutions and tissue samples. The reports include measurements of the heating caused by X-ray irradiation in ruby microcrystals, low-dose experiments examining damage rates as a function of incident X-ray energy up to 30 keV on a metallo-enzyme using a CdTe detector of high quantum efficiency as well as a theoretical analysis of the gains predicted in diffraction efficiency using these detectors, a SAXS examination of low-dose radiation exposure effects on the dissociation of a protein complex related to human health, theoretical calculations describing radiation chemistry pathways which aim to explain the specific structural damage widely observed in proteins, investigation of radiation-induced damage effects in a DNA crystal, a case study on a metallo-enzyme where structural movements thought to be mechanism related might actually be radiation-damage-induced changes, and finally a review describing what X-ray radiation-induced cysteine modifications can teach us about protein dynamics and catalysis. These papers, along with some other relevant literature published since the last Journal of Synchrotron Radiation Radiation Damage special issue in 2017, are briefly summarized below.

Field of study: Physics
Mineralogy and Petrology of the Santo Tomas-Black Mountain Basalt Field, Potrillo Volcanics, South-Central New Mexico

The Santo Tomas-Black Mountain basalts were erupted during the Quaternary from four centers. Six lava flows are present at Black Mountain, three at Santo Tomas, and one each at Little Black Mountain and San Miguel. The basalts are grouped into three major types of phenocryst mineralogy: (l) plagioclase abundant, (2) olivine abundant, and (3) both olivineand plagioclase abundant. All three types are alkali-olivine basalts, showing high alkali-silica ratios and total alkali content increasing with silica. Seven periods of basaltic extrusion among the centers have been established on the basis offieldevidence, phenocryst mineralogy, and pyroxene-olivineratios. K-Ar dates show the basalts to be less than 0.3 × 10 6 m.y. old. The basalts are thought to have originated from a single small, shallow magma chamber which was under the influence of a high thermal gradient during differentiation.

Field of study: Geology
Deprivation as a Learning Variable: Effects of Maintenance Schedule and Current Deprivation

The study investigated two aspects of food deprivation—maintenance schedule and current deprivation—in their effects on both speed and accuracy measures of learning. Male rats were assigned to 3 groups. High-High Ss were maintained at 22 hr. deprivation and trained 22 hr. after food removal. High-Low Ss were maintained at 22 hr. deprivation and trained 6 hr. after food removal. Low-Low Ss were maintained at 6 hr. deprivation and trained 6 hr. after food removal. The apparatus was a four-choice-point elevated T-maze. Food was presented following the final correct choice on each trial. After 10 training trials, all Ss were shifted to a 14-hr. maintenance schedule and 10 days later were given a single test trial. On both speed and accuracy measures for both the last training trial and the post-shift test-trial, the performance of the Low-Low group was significantly inferior to that of the two High groups while those groups did not differ from one another.

Field of study: Psychology
Exergy analysis on a heat pump working between a heat sink and a heat source of finite heat capacity rate.

The optimum performance of a pure subcritical refrigeration cycle depends significantly on the temperature lift of the heat source and sink. Therefore, the maximization of the system efficiency has to be linked to them. This paper shows an exergy analysis of each heat pump component (condenser, evaporator, expansion valve and compressor) considering that the heat source and sink are not at constant temperature. The performed study shows the components with more possibilities for improvement. Based on this analysis, the optimization of cycle parameters like subcooling and superheat as a function of the external conditions have been done. In addition, this work has demonstrated that the components having a higher influence in the system irreversibility's depends significantly on the temperature lift of the secondary fluids. Finally, the obtained results show potentials improvements of the efficiency up to 23% if the system is able to operate in the optimal subcooling and superheat.

Field of study: Engineering
Novel immunization protocol and ELISA screening methods used to obtain and characterize monoclonal antibodies specific for human light chain variable-region subgroups.

We have developed a novel immunization protocol for the production of a panel of high-affinity murine monoclonal antibodies (MoAbs) that are specific for each of the major human kappa and lambda light chain variable-region (VL) subgroups. Mice were injected with heat-precipitated human Bence Jones proteins or VL-related fragments emulsified in monophosphoryl lipid A (MPL) and trehalose dimycolate (TDM) at two- to four-week intervals over a seven-month period. A unique direct capturing enzyme-linked immunosorbent assay (ELISA) employing biotinylated monoclonal light chains was designed to select optimally immunized animals for hybridoma preparation and to screen culture supernatants for high-affinity anti-VL MoAbs. These methods have led to the generation of MoAbs that by ELISA react specifically with each of the four V kappa subgroups--V kappa I, V kappa II, V kappa III, and V kappa IV or five V lambda subgroups--V lambda I, V lambda II/V, V lambda III, V lambda IV, and V lambda VI. These reagents have been used successfully to establish, on the basis of VL subgroup, the monoclonal nature of serum or urinary immunoglobulins as well as those found in the cytoplasm or on the cell surface of monoclonal plasma cell or B-lymphocyte populations, respectively. The availability of anti-VL subgroup-specific MoAbs will facilitate the immunodiagnosis and study of patients with multiple myeloma, AL amyloidosis, and related B-cell proliferative disorders.

Field of study: Biology
Influence of lithium oxide excess and alumina on grain boundary resistance of Li6.75La3Zr1.75Nb0.25O12 solid electrolyte

Lithium oxide excess and powder bed method are conventionally used for synthesis of lithium-conducting solid electrolytes with cubic garnet structure. In this work Li 6.75 La 3 Zr 1.75 Nb 0.25 O 12 garnet was sintered at 1200 °C on alumina and zirconia supports with controlled amount of lithium oxide excess. It was found that the powder bed method did not prevent garnet pellets from alumina contamination. The quantity of aluminum penetrated into samples correlated with the amount of lithium oxide excess added and varied from 0.2 to 0.5 wt%, as indicated by ICP AES. In contrast to alumina, zirconia did not affect chemical composition of the pellets. Taking this into account to avoid any alumina contamination a modified powder bed method was developed. However, non-contaminated samples showed lower density after sintering when compared to contaminated ones. Lithium oxide excess in the samples is likely to react with the alumina with formation of eutectic that melts at 1200 °C. The liquid eutectic phase acts as a sintering aid and promotes densification up to relative densities of 96%. Electrical properties of the pellets were measured by EIS technique. Bulk conductivity of the dense pellets was 5 × 10 − 4  S/cm at 25 °C with the activation energy of 0.3 eV and depends on density. Due to grain boundary resistance dc-conductivity of pellets was lower than 10 − 8  S/cm at 25 °C with the activation energy of 0.8 eV. Possible reasons of high grain boundary resistance are discussed.

Field of study: Materials science
Use of differentially substituted selenomethionine proteins in X-ray structure determination.

Using heavily methionine-substituted T4 lysozyme as an example, it is shown how the addition or deletion of a small number of methionines can simplify the location of selenium sites for use in MAD phasing. By comparing the X-ray data for a large number of singly substituted lysozymes, it is shown that the optimal amino acid to be substituted by methionine is leucine, followed, in order of preference, by phenylalanine, isoleucine and valine. The identification of leucine as the first choice agrees with the ranking suggested by the Dayhoff mutation probability, i.e. by the frequency of amino-acid substitutions in the sequences of related proteins. The ranking of the second and subsequent choices, however, differ significantly.

Field of study: Chemistry
Facies architecture of the Stuttgart Formation (Schilfsandstein, Upper Triassic), central Germany, and its comparison with modern Ganga system, India.

The Stuttgart Formation (Schilfsandstein) is approximately 50 m thick in Thuringia, representing deposition during the “Mid-Carnian Wet Intermezzo”. Stratigraphically it occurs between the Grabfeld and Weser formations, which formed under arid conditions. It comprises NNE–SSW-trending elongate, anastomosing channelized sand-rich bodies with erosional bases (channel belts) that are several kilometres wide and pass laterally into predominantly mudstones deposited in interfluve areas. The source area of these clastics was the uplifted Norwegian Caledonides. Muddy interfluve facies is dominant in exposures in Thuringia, Central Germany. The Lower Stuttgart Formation has an unconformable base that is locally overlain by metre-thick “Basal Beds”. These consist of grey mudstones and thin sandstones deposited under humid conditions in predominantly shallow brackish water environments after a marine ingression via the Eastern Carpathian/Upper Silesian Gate. The following 30–40 m-grey, fine-grained sandstones, siltstones and mudstones were deposited in fluvial environments in channel belts and interfluve areas under humid conditions. These are followed by predominantly reddish mudstones and sandstones of mainly fluvial origin, deposited under somewhat drier conditions with seasonal droughts. The Upper Stuttgart Formation may be more than 16 m thick; it comprises reddish and grey sandstones and mudstones that were mostly deposited in lake delta settings by recurring flash floods. During the deposition of this unit climate was weakly humid with less prominent seasonal draughts. The modern Ganga Plain of India is an analogue for the depositional setting of the Stuttgart Formation. Climatic conditions in Ganga Plain are humid monsoonal with seasonal droughts and roughly comparable with those interpreted for Mid-Carnian times in Germany. The sandy deposits of incised channel belts and channels and muddy deposits of interfluve areas in the Ganga Plain are comparable with the sandstone-dominated channelized facies and mudstone dominated interfluve facies of the Stuttgart Formation, respectively.

Field of study: Environmental science, Geography
Late Holocene development of a mangrove ecosystem in southeastern Brazil (Itanhaém, state of São Paulo)

Most palynological studies of mangroves have been carried out in the Indo-Pacific region, but few have investigated these ecosystems along the southern Atlantic coast. This paper provides information on the palynology of a mangrove at Itanhaem, state of Sao Paulo, on the southeastern Brazilian coast. This mangrove occurs on microtidal flats adjacent to a fluvial-tidal channel mouth (Itanhaem River), part of an estuarine lagoon system established in the mid-Holocene. Pollen samples were collected from the surface and from bromeliad water in order to define the composition of modern pollen rain in the study area. The results show a strong presence of rain forest taxa in the mangrove pollen spectra, which differ from those obtained from northern Brazilian mangroves, which are characterized by higher percentages of the mangrove taxa Rhizophora and Avicennia . Based on palynological and 14 C chronological analysis of a shallow core measuring 135 cm in depth, the Itanhaem mangrove already existed by 1300 years BP and began expanding about 1000 years BP, reaching its present extent sometime after 300 years BP. Its evolution is related to the sedimentary filling of the estuarine–lagoonal depositional system. Two factors may have controlled the development of this mangrove: the relative increase of intertidal areas due to this sedimentary filling and the decrease in wave action and increase in pelitic deposition in the intertidal zone related to the partial closing of the estuarine–lagoonal inlets. These processes were favored by the advance of bayhead deltas and by the development of sand spits as a part of the regression of the Holocene strandplain.

Field of study: Environmental science, Geography
Awareness of Eco-label in Malaysia’s Green Marketing Initiative

Consumer awareness of the environment and preference for more environmentally benign products appears to be growing steadily around the developed world and also some developing countries. The Malaysian government too has responded very positively to this challenge. In 1996 Standards and Industrial Research Institute of Malaysia (SIRIM) lunched the national eco-labeling program verifying products according to environmental criteria such as Environmentally Degradable, Non-toxic Plastic Packaging Material, Hazardous Metal-Free Electrical and Electronic Equipment, Biodegradable Cleaning Agents and Recycled Paper.  Taking into consideration the infancy stage of the Malaysia green marketing initiative, traditional approach to evaluating local consumer receptiveness to the eco-label might not be suitable. This paper approaches the introduction of eco-label with two perspectives in mind. Firstly, while earlier studies from the western scholars use eco-label as a part of the augmented product, this study introduces eco-label as a separate moderating variable. Secondly, the choice of employees working in ISO14001 certified organization as the study population explore a potentially conducive place to initiate a systematic effort in developing a green consumer community. The result is very encouraging. This study has clearly shown that, with some exposure to environmental related experiences (such as those who were working with organization implementing the EMS) Malaysian consumer would indeed react positively to the eco-label. In fact, for situation that requires them to consider environmental aspects of a product that they wish to purchase, the eco-label will definitely be the crucial factor that will push them to make the right purchase choice.

Field of study: Business
Impairment of olfactory discrimination by blockade of GABA and nitric oxide activity in the honey bee antennal lobes.

Honey bees readily associate an odor with sucrose reinforcement, and the response generalizes to other odors as a function of structural similarity to the conditioned odor. Recent studies have shown that a portion of odor memory is consolidated in the antennal lobes (AL), where first-order synaptic processing of sensory information takes place. The AL and/or the sensory afferents that project into them show staining patterns for the enzyme nitric oxide synthase, which catalyzes the release of the gaseous transmitter nitric oxide (NO). The results show that pharmacological blockade of NO release impairs olfactory discrimination only when release is blocked before conditioning. Blockade of GABAergic transmission disrupts discrimination of similar but not dissimilar odorants, and does so when the block occurs before condition or before testing. These results show that GABA and NO regulate the specificity of associative olfactory memory in the AL.

Field of study: Biology, Psychology
Preparation of resveratrol from polygonum cuspidatum with enzymic dissolution

To optimize the best extraction procedure of resveratrol in Polygonum cuspidatum withenzymic dissolution.  Take the content of resveratrol as index to study the orthogonal design, and select the most suitable enzymes, then determined the condition of enzymic dissolution.  The most optimal for the enzymes amount is 0.20% SPE -002 0.17% SPE -005 0.08% SPE -007, and the optimum condition of enzymic dissolution is that the temperature is 40 ℃, the pH5.0, the enzymic dissolution period is 120 min, and the concentration of the substrate is 15%.  It adopts enzymic dissolution methods to change from polydatin to resveratrol of the Polygonum cuspidatum, after the enzymic dissolution, the content of resveratol from Polygonum cuspidatum was increased from 1.44 mg/g to 14.16 mg/g.

Field of study: Agricultural and Food sciences
Amplification of high-intensity ultrashort pulses of infrared radiation in low-pressure transversely excited CO2 amplifiers

It is shown that when high-intensity ultrashort radiation pulses are amplified in a transversely excited CO2 amplifier, lifting of the spatial degeneracy of the CO2-molecule vibrational levels by the optical Stark effect makes it possible to reduce the pressure of the amplifier active medium to a few atmospheres.

Field of study: Engineering, Physics