nils-herrmann/clean_scirepeval huggingface dataset:
Vitamin D-independent expression of chick brain calbindin-D28K.

A combination of calbindin-D28K-specific cDNA probes and polyclonal antisera were used to investigate expression of the calbindin-D28K in the vitamin D-deficient avian brain in vivo in response to pharmacological doses of the vitamin D3 metabolite, 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). Serum calcium levels were stimulated (2-fold) and intestinal calbindin-D28K expression (between 10- and 30-fold) by 1,25(OH)2D3 (6.5 nmol/animal) after 12 h. In marked contrast, steady-state whole brain levels of calbindin-D28K as judged by enzyme-linked immunoassay (ELISA) remained constant. Northern gel analysis revealed that three species of calbindin-D28K mRNA (2.0, 2.6 and 3.1 kb) were present a priori in the vitamin D-deficient chick brain and that administration of pharmacological doses (6.5 nmol/animal) of 1,25(OH)2D3 failed to influence their relative abundance. Separate but parallel dot blot hybridization analyses also confirmed that brain calbindin-D28K-mRNA levels were not influenced by 1,25(OH)2D3. These experiments demonstrate at the molecular level that, in contrast to the intestine, the gene encoding calbindin-D28K in the brain is regulated by mechanism(s) or factors which are independent of vitamin D status.

Field of study: Biology
The subchronic toxicity of acridine in the rat.

The subchronic toxicity of acridine was investigated in rats following dietary exposure at 0, 1, 10, 100 and 500 ppm for 13 weeks. The growth rate and food consumption were not affected by treatment and no clinical signs of toxicity were observed. There was a slight but significant decrease in spleen weight, both in absolute terms and as a percent of body weight, in the 500 ppm males and a slight increase in absolute thymus weight in the females of the same dose group. Both hepatic ethoxyresorufin O-deethylase (EROD) and pentoxyresorufin O-dealkylase (PROD) activities were slightly, but significantly, elevated in females in the 500 ppm dose group. No haematological or other biochemical changes were observed. Females also displayed dose-related increases in inorganic phosphate and uric acid levels. Treatment-related histopathological changes were seen in the thyroid, liver and kidney and included hepatic anisokaryosis and vesiculation of nuclei and glomerular adhesions, reticulin sclerosis and nuclear pyknosis in the kidney. Residue data showed a dose-dependent accumulation of acridine in liver, kidney and adipose with the highest concentration being found in the fat of the 500 ppm dose group. Based on these data, the no observable adverse effect level of acridine was judged to be 100 ppm or 12 mg/kg bw/day.

Field of study: Agricultural and Food sciences
Traditional and Novel Predictors of Classroom and Clerkship Success of Pharmacy Students

This study was designed to assess the extent to which 7 traditional and novel predictors contribute to overall pharmacy grade point average (pharmacy GPA), first through third year pharmacy GPA (1–3 year GPA), and clerkship GPA of pharmacy students.  This investigation used a convenience sample and a blinded retrospective record review of the first 3 class years of Doctor of Pharmacy students at Shenandoah University's Bernard  2001, and 2002).  Pharmacy College Admissions Test (PCAT) score, essay score, California Critical Thinking Dispositions Inventory (CCTDI) and Skills Test (CCTST) were all significant predictors of pharmacy GPA. PCAT and CCTDI contributed significantly to 1–3 GPA. Finally, only the CCTST proved to be a significant predictor of the clerkship GPA.  This study corroborated previous studies by concluding that several traditional predictors of students' performance appear to significantly predict academic o...

Field of study: Education, Medicine
Systematic increases in the thermodynamic response of hourly precipitation extremes in an idealized warming experiment with a convection-permitting climate model

Changes in sub-daily precipitation extremes potentially lead to large impacts of climate change due to their influence on soil erosion, landslides, and flooding. However, these changes are still rather uncertain, with only limited high-resolution results available and a lack of fundamental knowledge on the processes leading to sub-daily extremes. Here, we study the response of hourly extremes in a convection-permitting regional climate model (CPRCM) for an idealized warming experiment—repeating present-day observed weather under warmer and moister conditions. Ten months of simulation covering summer and early autumn for two domains over western Central Europe and western Mediterranean are performed. In general, we obtain higher sensitivities to warming for local-scale extreme precipitation at the original grid-scale of 2.5–3 km than for aggregated analyses at a scale of 12–15 km, representative for currently conventional regional climate models. The grid-scale sensitivity over sea, and in particular over the Mediterranean Sea, approaches 12%–16% increase per degree, close to two times the Clausius–Clapeyron (CC) relation. In contrast, over the dry parts of Spain the sensitivity is close to the CC rate of 6%–7% per degree. For other land areas, sensitivities are in between these two values, with a tendency for the cooler and more humid areas to show lower scaling rates for the most intense hourly precipitation, whereas the land area surrounding the Mediterranean Sea shows the opposite behaviour with the largest increases projected for the most extreme hourly precipitation intensities. While our experimental setup only estimates the thermodynamic response of extremes due to moisture increases, and neglects a number of large-scale feedbacks that may temper future increases in precipitation extremes, some of the sensitivities reported here reflect findings from observational trends. Therefore, our results can provide guidance within which to understand recent observed trends and for future climate projections with CPRCMs.

Field of study: Environmental science
Role of plant sterols in lipid lowering--a safety issue.

Sir,

In their review Gupta et al .1 failed to emphasize enough the crucial difference between plant sterols and stanols, namely their contrasting effects on plasma levels of plant sterols. Consumption of plant sterol esters raises plasma plant sterols whereas plant stanol esters lower them, by blocking their absorption. Evidence for this differential effect of plant sterols and stanols is derived both from population studies2 and clinical trials. In the latter, serum plant sterol levels increased by 35–120% on consumption of plant sterol 1.6 g daily,3 whereas taking 1.6 g of plant stanol …

Field of study: Medicine
Pleistocene Drainage Development in North Dakota

Successive glacial advances dammed and diverted existent streams during the Pleistocene Epoch in North Dakota causing meltwater to cut a complex system of trenches and change the drainage pattern from northeast- to southeast-trending. Most of the Pleistocene and pre-Pleistocene drainage channels in North Dakota are buried beneath glacial drift, but many buried preglacial valleys can be distinguished from buried glacial diversion trenches by a study of their width, shape, trend, and contents. Some of the diversion trenches are composite features comprised of segments ranging in age from preglacial to late Wisconsinan. The best example of such a trench in North Dakota is the modern Missouri River Valley.

Field of study: Geology
Quantifying fugitive gas emissions from an oil sands tailings pond with open-path Fourier transform infrared measurements

Fugitive emissions from tailings ponds contribute
significantly to facility emissions in the Alberta oil sands, but details on
chemical emission profiles and the temporal and spatial variability of
emissions to the atmosphere are sparse, since flux measurement techniques
applied for compliance monitoring have their limitations. In this study,
open-path Fourier transform infrared spectroscopy was evaluated as a
potential alternative method for quantifying spatially representative fluxes
for various pollutants (methane, ammonia, and alkanes) from a particular
pond, using vertical-flux-gradient and inverse-dispersion methods. Gradient
fluxes of methane averaged 4.3 g m −2  d −1 but were 44 % lower than
nearby eddy covariance measurements, while inverse-dispersion fluxes agreed
to within 30 %. With the gradient fluxes method, significant NH 3 
emission fluxes were observed (0.05 g m −2  d −1 , 42 t yr −1 ), and total alkane fluxes were estimated to be 1.05 g m −2  d −1 (881 t yr −1 ), representing 9.6 % of the facility
emissions.

Field of study: Environmental science
Endoscopic anatomy of the cerebellopontine angle: a study in cadaver brains.

The increasing trend toward performing minimally invasive neurosurgery may benefit from recent progress in using neuroendoscopic techniques to reduce trauma in patients who have undergone operations. Arterial and venous vessels, especially loops, may compress the central segment and cause hyperactive dysfunction of the nerves. Relationships of the anterior inferior cerebellar artery to the facial and vestibulocochlear nerves and the anterior inferior, and superior cerebellar arteries to the trigeminal nerve were studied. The authors report findings from an endoscopic study performed in cadaver heads via the retrosigmoid and retrolabyrinthine approaches. Arteries and veins were colored by injection of red and blue silicon rubber. The cerebellopontine angle (CPA) was examined using 2.7-mm and 4-mm-diameter rigid endoscopes at viewing angles of 0s degrees , 30s degrees , and 70s degrees . Well-known structures could be identified endoscopically without prior dissection, and the entire CPA could be explored. However, with a retrosigmoid or a retrolabyrinthine approach, the cerebellum had to be retracted to some extent to view the CPA. Moreover, wide dural exposure was required to maneuver the endoscope freely in the CPA. Use of the rigid fiberoptic endoscope is not yet superior to standard surgical techniques for approaching and exploring the CPA.

Field of study: Medicine
Design of a Tunable Polarization-Insensitive Absorber for L and S Bands Using Active Frequency-Selective Surface

A tunable polarization-insensitive absorber based on an active frequency-selective surface is proposed for electromagnetic (EM) wave absorption in the L and S bands. The frequency-selective surface consists of a diamond-shaped loop that is interconnected by varactor diodes. The proposed design is significant because of its inclusion of wideband tuning and its ability to easily change from single-band tunable absorption to dual-band absorption. The simulation results demonstrate that the absorption response (> 80%) can vary from 1.62 GHz to 3.66 GHz under the reverse bias voltage, thus creating a tunable range of 125.9%. The absorption region (> 90%) spans from 1.86 GHz to 3.31 GHz and generates a 78% tunable range. The single-band tunable absorber is characterised by an equivalent circuit model to obtain the circuit parameters and predict the absorption frequency. Furthermore, a dual-band absorbing structure is obtained by adding a metasurface directly to the single-layer structure, which can easily be changed from single-band absorption to dual-band absorption by separately controlling the bias voltages of the upper and lower unit cells. The two fabricated prototypes were measured using free-space technology, and the experimental results closely mirror the simulation results. Results show that the proposed structure achieves the dynamic control of EM wave absorption.

Field of study: Materials science
Structural refinement of the DNA-containing capsid of canine parvovirus using RSRef, a resolution-dependent stereochemically restrained real-space refinement method.

The canine parvovirus structure (CPV) [Tsao, Chapman, Agbandje, Keller, Smith, Wu, Luo, Smith, Rossmann, Compans & Parrish (1991).  251, 1456-1464] has been refined by a real-space refinement procedure [Chapman (1994).  The fit of an atomic model to electron density was optimized while taking into account the resolution limit of the data and the stereochemistry of the structure. The refined model had a reasonable free R factor [Brtinger (1992). Nature (London), 355, 472-4751 of 0.29. The method is particularly fast and convenient when only a small fraction of the crystallographic asymmetric unit needs to be refined, as is the case when there is high non-crystallographic redundancy. Cycles of refinement for virus capsids were completed in about 1/50th of the time required for equivalent reciprocal-space procedures.

Field of study: Chemistry
Influences on Malaysian Pharmacy Students' Career Preferences

To identify and evaluate factors affecting the career preferences of fourth-year bachelor of pharmacy (BPharm) students in Malaysia in the presence of a 4-year period of mandatory government service.  A validated self-administered questionnaire was used in this cross-sectional study to collect data from final-year BPharm students enrolled at 3 government-funded universities and 1 private university in Malaysia. Both descriptive and inferential statistics were used for data analysis.  Three hundred fourteen students responded (213 from public universities and 101 from the private university). Approximately 32% of public university students and 37% of private university students ranked their own interest in pharmacy as the reason for undertaking pharmacy degree studies; 40.4% of public and 19.8% of private university respondents stated that they would enter a nonpharmacy-related career upon graduation if given the choice. Public university students ranked hospital pharmacy as their choice of first career setting (4.39, p = 0.001), while private students ranked community pharmacy first (4.1, p = 0.002). On a scale of 1 to 5, salary received the highest mean score (3.9 and 4.0, p = 0.854) as the extrinsic factor most influencing their career choice.  Final-year students at Malaysian public universities were most interested in hospital pharmacy practice as their first career step upon graduation, while private university students were most interested in community pharmacy. The top 3 extrinsic factors rated as significant in selecting a career destination were salary, benefits, and geographical location.

Field of study: Education, Medicine
DISCOVERY OF NUCLEAR WATER MASER EMISSION IN CENTAURUS A

We report the detection of a 22 GHz water maser line in the nearest (D ~ 3.8 Mpc) radio galaxy Centaurus A (Cen A) using the Australia Telescope Compact Array (ATCA). The line is centered at a velocity of ~960 km s–1, which is redshifted by about 415 km s–1 from the systemic velocity. Such an offset, as well as the width of ~120 km s–1, could be consistent with either a nuclear maser arising from an accretion disk of the central supermassive black hole (SMBH), or with a jet maser that is emitted from the material that is shocked near the base of the jet in Cen A. The best spatial resolution of our ATCA data constrains the origin of the maser feature within <3 pc of the SMBH. The maser exhibits an isotropic luminosity of ~1 L ☉, which classifies it as a kilomaser, and appears to be variable on timescales of months. A kilomaser can also be emitted by shocked gas in star-forming regions. Given the small projected distance from the core, the large offset from systemic velocity, and the smoothness of the line feature, we conclude that a jet maser line emitted by shocked gas around the base of the active galactic nucleus is the most likely explanation. For this scenario we can infer a minimum density of the radio jet of 10 cm–3, which indicates substantial mass entrainment of surrounding gas into the propagating jet material.

Field of study: Physics
Business Cycle Theory and Econometrics

We outline in turn criticisms made by econometricians of the methods used in empirical business-cycle research and then criticisms made by business-cycle researchers of some methods used by econometricians. The aim is to clarify and in some cases correct these criticisms. Overall there is no conflict in using rigourous statistical procedures to study modern dynamic stochastic general equilibrium models. We also provide a concise bibliography of recent research on statistical methods for business-cycle models.

Field of study: Economics
Electron-beam-controlled laser utilizing the first overtones of the vibrational–rotational transitions in the CO molecule. II. Energy characteristics

An experimental investigation was made of the dependences of the output energy and efficiency of a pulsed electron-beam-controlled laser utilizing the first overtones of the CO molecule on the power and energy of excitation, characteristics of the active gas mixture, and Q factor of the resonator. In an apparatus having an active volume of 4 liters, a CO–N2–He gas mixture was excited and specific output energies of around 10 J/liter−1amagat−1 were realized at an efficiency of ~ 5%. It was found that in order to achieve high laser energy characteristics one must suppress lasing at the fundamental frequencies and use long relatively low-power pump pulses. A qualitative explanation is put forward for the observed behavior.

Field of study: Engineering, Physics
THE CONCEPT OF ECONOMIC IMPERIALISM

T HE term 'imperialism' has in the course of its rapid career become variegated and elusive to a degree. The word has been accepted as a key to the understanding of contemporary history. But there is reason to doubt whether the writers, who in the past used it most confidently in this sense, were certain of what they meant by it, and did not, in fact, become enmeshed in its ambiguity. There is, however, one connotation which tends to overshadow all others and to convey to the reader a clearcut meaning tantamount to a great historical revelation. This connotation is implied most clearly when the noun 'imperialism' is qualified by the adjective 'economic'. Indeed authors and propagandists are sometimes so certain of the economic interpretation as to drop the adjective and to assume that the reader cannot but think of special economic interests whenever the word imperialism is brought out.' The meaning of the word in this application is as follows. The men representing the interests of capital in the greater countries of the West have obtained control of the foreign and colonial policy of their governments. The nations which are commonly referred to by the term of 'western civilization' have been goaded by their capitalists into bringing weaker peoples oversea within their grip and into exploiting them. The same had been done by Venetians, Dutchmen and Englishmen in former centuries; but-so the doctrine runs-getting hold of undeveloped countries did not become a dominant factor in politics until capitalism reached its full efflorescence-that is to say, until the last decades of the nineteenth century. It is then that the age of imperialism-or of economic imperialism or of modern imperialism-Came into being. How long it lasted-whether imperialism is still vigorous in our days or already far on its decline-on this question opinions differ. They differ on other points too. Is the capitalist interest which dominates the whole movement rooted in the first

Field of study: Economics, History
Over-expression and B-cell linear epitope identification of Woodchuck hepatitis virus (WHV) core protein

目的 建立高效表达土拨鼠肝炎病毒核心蛋白(WHcAg)的方法并对其B细胞表位进行鉴定.方法 分别构建不同截短型WHcAg的质粒以了解能大量表达并形成WHV核心颗粒的区段,利用变性WHcAg制备单克隆抗体以寻找能与WHcAg线性B细胞表位结合的单克隆抗体.结果 WHcAg前144或149氨基酸残基能够大量表达并能形成颗粒样结构.这2种截短型WHcAg能够在大肠杆菌中表达并组装成直径为34 nm的核心颗粒,最终纯化获得毫克级的核心蛋白.截短型WHcAg保留了全长WHcAg的抗原性,而且变性WHcAg存在另外的B细胞线性表位,利用变性WHcAg进行免疫制备单克隆抗体获得的5株抗体均针对WHcAg的N末端表位,该表位在WHcAg和HBcAg高度保守.结论 建立了高效表达WHcAg的方法,制备了针对WHcAg单克隆抗体.并对WHcAg的线性B细胞表位进行了鉴定,发现WHcAg和HBcAg的N末端存在共同的线性B细胞表位。

Field of study: Biology
Assessment of short-term beach sediment change in the Volta Delta coast in Ghana using data from Unmanned Aerial Vehicles (Drone)

Reduced sediment in delta beach systems affects delta coast topography and influence delta beach evolution. It opens the deltaic environment up to severe ocean waves and tide attack, which threatens vulnerable coastal communities and increases the risk of the inhabitants. Changes in the beach sediment systems vary from few meters to several kilometres and from hours/days (short term) to decades (long term). Various methods have been developed to analyse changes in beach sediments. This study used Unmanned Aerial Vehicle (UAV or Drone) approach to assess short-term sediment dynamics (from April 2017 to April 2018) in three vulnerable beach systems at Old Ningo (west), Fuveme (central) and Keta (east) communities within the Volta Delta coast in Ghana. High-resolution Digital Elevation Models (DEMs) were developed from the drone images captured, which enabled perpendicular profiles to be generated. Sampled sediments were analysed to determine variation in sizes along the coast. Analysis of the profiles revealed that for the period between April 2017 and April 2018, the beach system at Ningo recorded a net loss of about 8,850 m3 volume of sediment; at Fuvemeh the beach system gained about 12,700 m3 net volume of sediment; in Keta the beach system also gained about 12,100 m3 net volume of sediment. Sediment size analysis revealed that the western section has a relatively finer grain size compared to the east. The coast experienced lower waves between January and February and higher waves between July and August. The pattern of change in the sediment dynamics follows the changing trend in the wave height observed in the region. This indicates that wave dynamics is a major driver of short term sediment change in the Volta delta beach systems. Increased wave intensity as a result of climate change will have a significant impact on the delta beach systems, which will increase erosion and flooding incidence.

Field of study: Environmental science
Using Conductance Ratio to On-line Monitor the Switch Performance

Through analyzing the power flow in a switch network,a calculation method and formula and its program block diagram of conductance ratio of every switch are put forward in this paper.The conductance ratio can be used as a measurable criterion in monitoring switch performance.Under the condition of given power flow,the power flow distribution of different switches can be calculated out using conductance ratio.So the problem of switch lifetime performance data well be determined.

Field of study: Engineering, Physics