nils-herrmann/clean_scirepeval huggingface dataset:
Spectral Compensation for Multicarrier Communication

Spectral compensation is an information-processing technique applied in the transmitter to improve the spectral efficiency of multicarrier modulation under a given power spectral density constraint. A set of carefully chosen tones, the so-called information tones, carries data. The remaining tones, referred to as compensation tones, are modulated with a linear combination of the data, such that the spectral characteristic of the transmit signal and thus the throughput are improved. This paper investigates strategies to find the set of compensation tones and presents the optimal solution for the linear combination of the data given the tone-set split. The optimality criterion is maximization of throughput for a time-dispersive Gaussian channel known to the transmitter. Furthermore, a suboptimal design is proposed, which has low runtime-complexity and achieves near-optimal performance.

Field of study: Engineering
Microbial community potentially responsible for acid and metal release from an Ostrobothnian acid sulfate soil

Soils containing an approximately equal mixture of metastable iron sulfides and pyrite occur in the boreal Ostrobothnian coastal region of Finland, termed ‘potential acid sulfate soil materials’. If the iron sulfides are exposed to air, oxidation reactions result in acid and metal release to the environment that can cause severe damage. Despite that acidophilic microorganisms catalyze acid and metal release from sulfide minerals, the microbiology of acid sulfate soil (ASS) materials has been neglected. The molecular phylogeny of a depth profile through the plough and oxidized ASS layers identified several known acidophilic microorganisms and environmental clones previously identified from acid- and metal-contaminated environments. In addition, several of the 16S rRNA gene sequences were more similar to sequences previously identified from cold environments. Leaching of the metastable iron sulfides and pyrite with an ASS microbial enrichment culture incubated at low pH accelerated metal release, suggesting microorganisms capable of catalyzing metal sulfide oxidation were present. The 16S rRNA gene analysis showed the presence of species similar to Acidocella sp. and other clones identified from acid mine environments. These data support that acid and metal release from ASSs was catalyzed by indigenous microorganisms adapted to low pH.

Field of study: Biology, Environmental science
Effect of Pinellia ternata lectin on membrane currents of mouse motor nerve terminals.

Pinellia ternata lectin (PTL) extracted from the fresh juice of rhizome of pinellia ternata used as a traditional Chinese medicine facilitated the quantal release of acetylcholine (ACh) in the mouse motor nerve terminals and formed cation channels in artificial lipid bilayer. Here we report the action of PTL on presynaptic membrane currents of motor nerve terminals. The experiments were performed on the intercostal nerve triangularis sterni muscle preparations. By means of the perineurial recording, the effects of PTL on the sodium current in the preterminal part, three potassium currents and two calcium currents generated from the nerve terminals were investigated. The results show that PTL increases voltage-dependent fast Ca2+ current (ICa.f), Na+ current (INa) and Ca(2+)-activated K+ current (IK,Ca) without action on either the voltage-dependent fast K+ current (IK,f) or the slow K+ current (IK,s). These effects are irreversible, but can be reversed by mannan, the specific binding sugar for PTL. The total action of PTL can be considered to raise [Ca2+]i by promoting Ca2+ influx, and then facilitate the neurotransmitter release. To our knowledge, this is the first report about the influence of lectin on presynaptic membrane currents at mammalian motor nerve terminals.

Field of study: Chemistry
SMALL SCALE STEAM INJECTION COOKER FOR CORN MEAL.

Acontinuous laboratory cooker for 0.2 kg/min of ground corn {Zea Mays) was developed and evaluated. Pure corn starch and corn meal were used as feedstocks. Solids concentrations from 10 to 25% were examined. The feedstocks were hydrolyzed with alphaamylase at temperatures from 100° to 125 °C, and saccharified at 60 °C with amyloglucosidase. Slurry samples were analyzed for total reducing sugars (TRS). The results were analyzed using a response surface technique. The dependent variables were: (a) material efficiency, the fraction of starch converted to TRS, (b) conversion ratio, the ratio of TRS in the output supernatant to the input solids concentration, and (c) energy ratio, the ratio of the higher heating value of TRS produced to electrical and steam energy used in the process. The operation of the cooker was limited to 18% corn meal solids due to plugging of the viscous product. In order to operate at a conversion ratio greater than 70% it was necessary to operate the cooker at 105 °C for pure starch and 125 °C for corn meal. This resulted in material efficiency in excess of 90% for both feed stocks.

Field of study: Agricultural and Food sciences
STABILITY ANALYSIS OF SLOPES REINFORCED WITH GRAVITY WALLS UNDER THE EARTHQUAKE LOADING

Seismic stability analysis is based on the certain potential sliding surface and the yield acceleration of a slope.The potential sliding surface is considered to be a composite of a number of straight lines,and then the potential sliding mass is divided into a number of triangular wedges by a series of inclined straight lines.By the assumption that the slope material obeys a Mohr-Coulomb criterion,the upper bound method and multi-wedge translations mechanism are used to calculate the rate of external work and the rate of energy dissipation for each triangular wedges,respectively,and so to establish the multivariate function to calculate the yield acceleration of reinforced slope.The yield acceleration and the corresponding potential sliding surface can be obtained by optimization.Thence,a new approach is presented in this study to consider the seismic stability of gravity retaining walls.At last,an example is shown to illustrate the method.The influence of shear strength parameters and wall roughness to the yield acceleration and potential sliding surface are analyzed.

Field of study: Engineering
Impact of Spacing of Practice on Learning Brand Name and Generic Drugs

To test the impact of schedules of retrieval practice on learning brand and generic name drug information in a self-paced course.  Students completed weekly quizzes on brand and generic name conversions for 100 commonly prescribed drugs. Each student completed part of the drug list on a schedule of equal, expanding, or contracting spacing, one practice (massed) or study only in a partial block design.  On measures of long-term retention, the contracting spacing schedule led to superior retention (67%) compared to the massed practice (50%) and study-only condition (46%); contracting practice also was significantly higher than expanding practice (58%,) or equal practice (59%). Overall performance decreased by almost 50% (final exam 95%, long-term retention 55%) over a 6-week period.  A contracting spacing schedule was the most effective schedule of practice, and all spacing schedules were superior to massed practice or study-only conditions.

Field of study: Education, Medicine
Language acquisition without Universal Grammar: a general nativist proposal for L2 learning

This article explores the prospects for a 'general nativist' theory of first and second language acquisition. A modular acquisition device that does not include Universal Grammar (UG) is outlined and its role in the emergence of an L1 is considered. The relevance of this proposal for a theory of SLA is then explored, leading to the suggestion that the properties and outcome typical of postadolescent L2 learning can be traced to the fact that adults have only partial access to the L1 acquisition device.

Field of study: Linguistics
Lithium ion conduction in doped LaLiO2 system

Solid solutions of the lithium ion conductor LaLiO 2 were synthesized using a solid-state reaction method. For the strontium-doped system, Sr 2 + was partially doped at the La sites with the composition La 1 −  x Sr x Li 1 +  x O 2 ( x  = 0.1, 0.2), which introduced excess lithium into the structure, while for the magnesium-doped system, Mg 2 + was partially doped at the Li + site with LaLi 1 − 2 y Mg y O 2 ( y  = 0.1, 0.2) which introduced Li + vacancies. The magnesium-doped sample with y  = 0.1 in LaLi 1 − 2 y Mg y O 2 showed higher ionic conductivity of 9.22 × 10 − 5  S cm − 1 than that of the respective Sr doped sample of x  = 0.1 in La 1 −  x Sr x Li 1 +  x O 2 (4.64 × 10 − 5  S cm − 1 ) at 300 °C. Higher ionic conductivity in the Mg doped system indicates that vacancies led to high lithium ion conduction in LaLiO 2 . The doped LaLiO 2 systems are a novel lithium conductive oxides family.

Field of study: Materials science
New crystal forms of a mu-class glutathione S-transferase from rat liver.

: Two new crystal forms of isoenzyme 3-3 of rat liver glutathione S-transferase (GST 3-3) have been obtained. They were grown under essentially the same crystallization conditions as those reported for the C2 crystal form [Fu, Rose, Chung, Tam & Wang (1991). . The new crystals belong to space group P2(1) with one form having cell dimensions a = 101.6, b = 69.5, c = 81.4 A, and beta = 113.6 degrees, and the other form having cell parameters a = 97.4, b = 81.1, c = 69.4 A and beta = 109.2 degrees. These new crystals diffract to at least 2.5 A, resolution. The molecular packing arrangements in these P2(1) crystals have been found by molecular replacement studies.

Field of study: Chemistry
An Implementation Technique of Database Encryption

Applying encryption technique is a valid and economical means of protecting important information in modern society. The system of data encryption protection in databases mostly relates to five problems: encryption algorithm, encryption granularity, the creation and management of the key encryption?the operation of demanding manipulation and the influence of the system capability. An implementation technique of database encryption is introduced in this paper, combined with which the above problems are analyzed and discussed in this paper.

Field of study: Computer science
Cenomanian–Turonian transition in a shallow water sequence of the Sinai, Egypt

Environmental and depositional changes across the Late Cenomanian oceanic anoxic event (OAE2) in the Sinai, Egypt, are examined based on biostratigraphy, mineralogy, δ13C values and phosphorus analyses. Comparison with the Pueblo, Colorado, stratotype section reveals the Whadi El Ghaib section as stratigraphically complete across the late Cenomanian–early Turonian. Foraminifera are dominated by high-stress planktic and benthic assemblages characterized by low diversity, low-oxygen and low-salinity tolerant species, which mark shallow-water oceanic dysoxic conditions during OAE2. Oyster biostromes suggest deposition occurred in less than 50 m depths in low-oxygen, brackish, and nutrient-rich waters. Their demise prior to the peak δ13C excursion is likely due to a rising sea-level. Characteristic OAE2 anoxic conditions reached this coastal region only at the end of the δ13C plateau in deeper waters near the end of the Cenomanian. Increased phosphorus accumulations before and after the δ13C excursion suggest higher oxic conditions and increased detrital input. Bulk-rock and clay mineralogy indicate humid climate conditions, increased continental runoff and a rising sea up to the first δ13C peak. Above this interval, a dryer and seasonally well-contrasted climate with intermittently dry conditions prevailed. These results reveal the globally synchronous δ13C shift, but delayed effects of OAE2 dependent on water depth.

Field of study: Environmental science
Anisotropy of transport properties normal and parallel to the tape plane in Bi-2223/Ag tapes

We have performed transport, resistivity and critical current measurements on Bi-2223/Ag tapes with current directions both parallel and perpendicular to the tape plane in magnetic fields up to 7 T and 50<T<250 K. We find that the resistivity along the tape normal (nominal c-axis in a textured tape) is metallic, scales with the in-plane resistivity at all fields and is dramatically reduced from single crystal c-axis values. Similarly, the critical current along the tape normal exhibits magnetic field and field orientation dependences similar to those for current flow along the tape plane. These results indicate that current flow along CuO/sub 2/ planes dominates current transport even along the tape normal in highly textured tapes.<<ETX>>

Field of study: Physics
In situ microscopy as online tool for detecting microbial contaminations in cell culture.

Microbial contamination in mammalian cell cultures causing rejected batches is costly and highly unwanted. Most methods for detecting a contamination are time-consuming and require extensive off-line sampling. To circumvent these efforts and provide a more convenient alternative, we used an online in situ microscope to estimate the cell diameter of the cellular species in the culture to distinguish mammalian cells from microbial cells depending on their size. A warning system was set up to alert the operator if microbial cells were present in the culture. Hybridoma cells were cultured and infected with either Candida utilis or Pichia stipitis as contaminant. The warning system could successfully detect the introduced contamination and alert the operator. The results suggest that in situ microscopy could be used as an efficient online tool for early detection of contaminations in cell cultures.

Field of study: Biology, Engineering
Histidine and thermal copolymers of amino acids containing histidine as prebiotic Inhibitor for the template-directed formation of oligoguanylate on a poly(C) template

Possibility of the cooperative chemical evolution of nucleic acids and proteins has been investigated using the template-directed formation of oligoguanylate with amino acids and thermal copolymers of amino acids, in which strong inhibition by histidine containing thermal copolymer and histidine itself was observed. The inhibition is regarded as prebiotic enzymatic activities for the hydrolysis of activated nucleotide monomer and the formation of pyrophospho-capped oligoguanylate.

Field of study: Chemistry
Peripheral normativity: Literacy and the production of locality in a South African township school

This paper reports on an ethnographic study of classroom practices in a township school in the Wesbank settlement near Cape Town, South Africa. Focusing on the ways in which a multilingual and highly diverse student population confronts English literacy, we argue for a view in which norms are seen as emergent and contingent on occasion, place, social and sociolinguistic environment. The school, Wesbank High, is by all standards a ‘peripheral’ school in a marginalised community struggling with very serious socio-economic marginalisation corroborated with a dearth of high-quality public provisions in the settlement. The school is one of these provisions, and teachers and learners share ideals of upward social mobility, often crystallised in discourses on English as an instrument of spatial and social mobility. Learners’ writing in English, however, displays many features of ‘grassroots literacy’—sub-elite literacy characterised by orthographic, syntactic, lexical and pragmatic peculiarities. These peculiarities – ‘errors’ when seen from a punitive and homogeneist viewpoint – appear to be shared by learners and teachers alike, both groups being inserted in a particular, peripheral economy of English. ‘Errors’, thus, are systemic , normal and hence normative , they do not preclude effective and differentiating assessments of learners’ performance but are a productive, positive mechanism that allows teachers to reach a degree of effectiveness with their marginalized and heterogeneous groups of learners. We witness the production of locality through peripheral normativity, as well as the creation of a problem of ‘mobility’ when such locally valid forms are deployed elsewhere. These findings have implications for globalisation theory and views of systemic power in Third-World classroom environments.

Field of study: Education, Linguistics
Moinian Stratigraphy and the Problem of the Central Ross-shire Inliers

A stratigraphical synthesis is proposed for a large area of Moinian (late pre-Cambrian) rocks in the northwestern Highlands of Scotland. Lewisian basement occurs in central Ross-shire as a sheet-like body found at a high stratigraphic level within the Moinian (Sutton and Watson, 1962). We suggest that the Lewisian sheet is separated from the underlying rocks by a major tectonic discontinuity, or slide, which may be delineatedfor a distance of over 250 km. The age of this slide is discussed in relation to the regional structural and metamorphic history of the Moinian.

Field of study: Geology
Interpretation of the soft strengths of a powerful country of sports

A powerful country of sport should be a country that is the first class and has produced significant influ-ence domestically and internationally in terms of the level of development of various sports undertakings.From the perspective of soft strengths,a powerful country of sport is a country that has domestic influence on its sports de-velopment potentials and international influence in terms of such soft strengths as sport culture attraction,sport value view attraction,sport system attraction as well as building international sport rules and an international image.The ways to boost the soft strengths of a powerful country of sport include the ways to boost the sports cultural strengths of China,which include sports value views and sport cultural spirits,and the ways to boost the soft strengths of sport of China and to strive for sport voicing rights in the international sports community by means of major sports games and sports activities held internationally and domestically.

Field of study: Education
Leaf expansion and cell division are affected by reducing absorbed light before but not after the decline in cell division rate in the sunflower leaf

The effect of absorbed photosynthetic photon flux density (PPFD) on leaf expansion is a key issue for analysing the phenotypic variability between plants and for modelling feedback loops. Expansion and epidermal cell division in leaf 8 of sunflower were analysed in a series of five experiments where absorbed photosynthetic photon flux density (PPFD) was reduced either by shading or by covering part of the leaf area. These treatments were imposed at different times during leaf development. Expansion and cell division were affected by a reduction in absorbed PPFD only in the first part of leaf development, while the leaf area was less than 2% of its final value and while absolute expansion rate was slow. In contrast, it was not affected if imposed later when the leaf was visible and absolute expansion rate was at maximum. A reduction in absorbed PPFD caused the same reduction in expansion and in cell division whether it was due to a reduction in incident PPFD or to a reduction in photosynthetic leaf area, suggesting that carbon metabolism was involved. Relative expansion rate recovered to control levels when relative division rate began to decline, in all experiments and in all zones of a leaf. This was probably linked to the source-sink transition, after which the leaf had such a high priority in carbon allocation that it was largely insensitive to changes in absorbed PPFD. The final leaf area was therefore closely related to the cumulated PPFD absorbed by the plant from leaf initiation to the end of exponential cell division.

Field of study: Environmental science
Nanocomposite Based on Functionalized Gold Nanoparticles and Sulfonated Poly(ether ether ketone) Membranes: Synthesis and Characterization

Gold nanoparticles, capped by 3-mercapto propane sulfonate (Au-3MPS), were synthesized inside a swollen sulfonated poly(ether ether ketone) membrane (sPEEK). The formation of the Au-3MPS nanoparticles in the swollen sPEEK membrane was observed by spectroscopic and microscopic techniques. The nanocomposite containing the gold nanoparticles grown in the sPEEK membrane, showed the plasmon resonance λmax at about 520 nm, which remained stable over a testing period of three months. The size distribution of the nanoparticles was assessed, and the sPEEK membrane roughness, both before and after the synthesis of nanoparticles, was studied by AFM. The XPS measurements confirm Au-3MPS formation in the sPEEK membrane. Moreover, AFM experiments recorded in fluid allowed the production of images of the Au-3MPS@sPEEK composite in water at different pH levels, achieving a better understanding of the membrane behavior in a water environment; the dynamic hydration process of the Au-3MPS@sPEEK membrane was investigated. These preliminary results suggest that the newly developed nanocomposite membranes could be promising materials for fuel cell applications.

Field of study: Materials science
A Robust Journey in the New Millennium

A brief search through Current Index to Statistics found more than 3,000 entries with "robust" or "robustness" as key words. That this number exceeded the number of appearances for "density," "rank," "bootstrap," "censored," or "smoothing" suggests that the name of this field might also be an appropriate appellation for those doing the research. Here we present a very personal view of a few of the most fundamental insights offered by the study of robustness and suggest some promising areas for future robust travel.

Field of study: Mathematics
Incommensurate spin density waves in iron aluminides.

Neutron diffraction in Fe(Al) reveals incommensurate spin density waves (SDWs) in alloys known to be spin glasses. The wave vectors for crystals of Fe(34Al), Fe(40Al), and Fe(43Al) show n varying from 11 to 6 for q-->=2pi(h+/-1/n,k+/-1/n,l+/-1/n)/a(0), where (h,k,l) and a(0) characterize the parent bcc lattice of the CsCl structure. The magnetic reflections are present far above the spin-glass freezing temperatures. These SDWs keep the spins on nearest-neighbor Fe atoms close to parallel, in contrast with SDWs in Cr, which keep nearest-neighbor spins close to antiparallel.

Field of study: Physics
Dynamical properties of constrained drops

In this communication we analyze the behavior of excited drops contained in spherical volumes. We study different properties of the dynamical systems, i.e. the maximum Lyapunov exponent MLE, the asymptotic distance in momentum space d∞ and the normalized variance of the maximum fragment. It is shown that the constrained system behaves as undergoing a first-order phase transition at low densities while as a second-order one at high densities. The transition from liquid-like to vapor-like behavior is signaled both by the caloric curves, the thermal response functions and the MLE. The relationship between the MLE, d∞, and the caloric curve is explored.

Field of study: Physics
HLA class II homozygosity confers susceptibility to common variable immunodeficiency (CVID)

Most cases of CVID occur sporadically, but familial cases do also occur and 15% of the patients with the disease have first degree relatives with IgA deficiency (IgAD). Our purpose was to study CVID association with HLA class II alleles and to ascertain whether this disease shares a common genetic background with IgAD in our population. Patients with CVID (n = 42), were typed using gene amplification and sequence‐specific oligonucleotide probing for HLA‐DRB1, DRB3, DQA1 and DQB1 loci and their typing compared with that of 96 IgAD and 334 healthy controls. We observed a positive association between non‐Asp residues at position 57 of the HLA‐DQβ chain and CVID, although much weaker than in IgAD. Further, we found an association between CVID and homozygosity for genes encoding HLA class II molecules, especially HLA‐DQ, not seen in IgAD. The data support the hypothesis that a restricted diversity of HLA class II molecules may contribute to susceptibility to CVID.

Field of study: Biology, Medicine