bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analytical Method Development and Validation of UV-visible
Spectrophotometric Method for the Estimation of Vildagliptin in Gastric
Medium
Authors: Kumari Beena , Khansili Aparna 
Published: August 2020

Abstract
Background Vildagliptin is an antidiabetic agent, belongs to the
dipeptidyl peptidase IV (DPP-4) inhibitors.
Objective The aim of investigation was to develop a simple UV-visible
Spectrophotometric method for the determination of vildagliptin in its pure form
and pharmaceutical formulations, further to validate the developed method.
Material and Methods Vildagliptin was estimated using UV-Visible double
beam spectrophotometer at the wavelength of maximum absorption (210 nm) in
acidic medium containing 0.1N HCl. The drug was characterized by melting point,
Differential Scanning Calorimetry (DSC), and Fourier Transform Infra-Red (FTIR)
techniques. The analysis of the drug was carried out by novel UV-Visible method
which was validated analytical parameters like linearity, precision, and
accuracy as per guidelines laid down by International Conference on
Harmonization (ICH).
Result Melting point of drug was found 154°C which is corresponds
to its actual melting range. Similarly by the interpretation of spectra the drug
was confirmed. The linear response for concentration range of 5–60
µg/ml of vildagliptin was recorded with regression coefficient
0.999. The accuracy was found between 98–101%. Precision for
intraday and interday was found to be 1.263 and 1.162 respectively, which are
within the limits. To establish the sensitivity of the method, limit of
detection (LOD) and limit of quantification (LOQ) were determined which were
found to be 0.951 µg/ml and 2.513 µg/ml
respectively.
Conclusion The UV method developed and validated for vildagliptin drug
was found to be linear, accurate, precise and economical which can be used for
the testing of its pharmaceutical formulations.
Outcomes of Pulmonary Endarterectomy Operation Concomitant with Cardiac Procedures
Authors: Erdem Hasan , Korun Oktay , Yanartaş Mehmed , Taş Serpil , Erden Benay , Yerlikhan Onur , Erkilinç Atakan , Kaymaz Cihangir , Sunar Hasan , Yildizeli Bedrettin 
Published: August 2020

Abstract
Background The aim of this study was to analyze the results of pulmonary endarterectomy (PEA) performed simultaneously with additional cardiac procedures in a single tertiary-level center.
Methods Data of patients who underwent PEA with additional cardiac procedures for chronic thromboembolic pulmonary hypertension (CTEPH) in our clinic were retrospectively reviewed using patient records.
Results Between March 2011 and April 2019, 56 patients underwent PEA with additional cardiac surgery. The most common additional procedure was coronary artery bypass grafting (21 patients; 38%). The median intensive care unit and hospital stays were 4 (3–6) days and 10 (8–14) days. Mortality was recorded in six patients (11%). In multivariate analysis, only preoperative pulmonary vascular resistance (PVR) (p = 0.02; odds ratio [OR]: 1.003) and cardiopulmonary bypass duration (p = 0.02; OR: 1.028) were associated with mortality. When the cutoff value of 1000 dyn.s.cm−5 was taken in the receiver operating characteristic curve analysis, preoperative PVR predicted mortality with 83% sensitivity and 94% specificity (area under curve = 0.89; p < 0.01).
Conclusion PEA for CTEPH may be performed safely with other cardiac operations. This type of surgery is a complex procedure that should be performed only in expert centers. Patients with high preoperative PVR are at increased risk of perioperative complications.
Energetics and kinetics of substrate analog-coupled staphylococcal nuclease folding revealed by a statistical mechanical approach
Authors: Mizukami Takuya , Furuzawa Shunta , Itoh Satoru G. , Segawa Saho , Ikura Teikichi , Ihara Kunio , Okumura Hisashi , Roder Heinrich , Maki Kosuke 
Published: August 2020

Significance
The structural/energetic basis of ligand binding-coupled protein conformational changes remains elusive. There are two limiting scenarios: conformational selection (CS) and induced-fit (IF). The difference is whether the ligand binds to the protein before (IF) or after (CS) the conformational change. To elucidate this complex reaction, we developed a statistical mechanical model considering the physical interactions and applied it to the staphylococcal nuclease folding coupled with binding of a small-molecule ligand. Quantitative modeling revealed that a ligand-dependent CS-to-IF shift resulted from the stabilization of the compact transition state by Coulombic interactions causing a change in the reaction flux ratio. The model was supported by experimental/computational evidence for transient formation of an encounter complex of the ligand with a denatured protein state.
The esophageal gland mediates host immune evasion by the human parasiteSchistosoma mansoni
Authors: Lee Jayhun , Chong Tracy , Newmark Phillip A. 
Published: August 2020

SignificanceSchistosomes are parasitic flatworms infecting hundreds of millions of people. As they alternate between mammalian and molluscan hosts, their survival and propagation depend upon stem cell proliferation and differentiation. Tracking the fate of these stem cells during early intramammalian development, we find that the esophageal gland, an accessory digestive organ, develops before the rest of the digestive system is formed and feeding begins, suggesting a role for this organ beyond nutrient uptake. We show that schistosomes lacking the esophageal gland die in naive mice but survive in immunodeficient mice lacking B cells; they are unable to lyse ingested immune cells before passing them into the gut. These results unveil an immune-evasion mechanism, which is essential for schistosome survival and pathogenesis.
Protein nanoribbons template enamel mineralization
Authors: Bai Yushi , Yu Zanlin , Ackerman Larry , Zhang Yan , Bonde Johan , Li Wu , Cheng Yifan , Habelitz Stefan 
Published: August 2020

Significance
How does enamel achieve its remarkable microstructure? This study reveals that the cleaved enamel protein amelogenin adopts a ribbon-like supramolecular structure that controls the growth of mineral into nanofibers. Protein nanoribbons of 15 to 20 nm in width were identified in dental enamel and replicated from a recombinant protein mimicking an enzymatic cleavage product of human amelogenin. In mineralization experiments, these protein structures templated the growth of highly oriented apatite nanofibers along their backbone from an amorphous precursor. In accordance with the natural process of enamel development, this in vitro model suggests that the ability of amelogenin nanoribbons to guide fibrous apatite growth is regulated by enzymatic processing and their interaction with acidic nonamelogenin proteins in the developing enamel matrix.
Lysosomal activity regulatesCaenorhabditis elegansmitochondrial dynamics through vitamin B12 metabolism
Authors: Wei Wei , Ruvkun Gary 
Published: August 2020

SignificanceThe balance of mitochondrial fission and fusion, two aspects of mitochondrial dynamics, is important for mitochondrial function. In this study, we show thatCaenorhabditis eleganslysosomal activity regulates mitochondrial dynamics by affecting mitochondrial fission through interfering the metabolism of a micronutrient, vitamin B12. Vitamin B12 is exclusively obtained from diets in animals, includingC. elegansand humans, and its uptake is mediated by the lysosome. We show that lysosomal dysfunction causes vitamin B12 deficiency that leads to reduction of methionine and S-adenosylmethionine to in turn increase mitochondrial biogenesis and fission. Our study provides insight on the interactions between mitochondrial function and micronutrient metabolism.
Associated motion, direction and (exchoative) aspect in Ethiopian Komo
Authors: Otero Manuel A. 
Published: August 2020

AbstractKomo (Koman) of Ethiopia has an obligatory paradigm ofdeictic directional(dd) verb morphology that, among its functions, indicatesdirectionofmotionrelative to a deictic reference point,associated motionand grammaticalaspectwhen collocated with verb roots of different semantic classes. The semantic components of amotion eventunderlie the Komoddsystem and the grammatical aspect of a predicate can be directly mapped to the bounded/unboundedpathprofile. The Associated Motion function contains a bounded path which entails arrival at or departure from a reference point and, as a result, imparts aspectual telicity to the predicate. The Direction function by contrast, contains an unbounded path that expresses motion towards a reference point and does not impart aspectual telicity. Further, some morphemes express exchoativity, or the ‘exiting’ of a state, a rare if unattested grammatical category.
Markers of epistemic modality and their origins
Authors: Engberg-Pedersen Elisabeth 
Published: August 2020

AbstractNative deaf signers express epistemic modality by different means: mental-state words, clause-internal particles, signs indicating hypothesis, and nonmanually. The data for this study come from two unrelated sign languages, Danish Sign Language and Japanese Sign Language. In dialogues the signers use both calques of majority-language words and signs that appear to have emerged in the sign languages only. Based on the multifunctionality of some word forms, the origin of the epistemic modal particles may be traced back to tags, interjections, and lexical signs, a route motivated by interaction and also found in unrelated spoken languages. Furthermore, in both sign languages, the first-person pronoun can be used, without a verb, as an epistemic “anchor” of a proposition, a construction that seems specific to languages in the gestural-visual modality. Another modality-specific feature is the possibility of transferring the expression of a marker of epistemic uncertainty from one articulator to another.
Dietary composition of birds in isolated ecosystems: a case study of Black Wood Pigeon in Republic of Korea
Authors: Choi Soon Kyoo , Park Yung Chul , Park Sung Wan , Kim Jae Woong , Kim Woo Yuel 
Published: August 2020

ABSTRACTWe studied the feeding ecology of the Black Wood Pigeon (Columba janthina), a species endemic to the East Asian Pacific Islands, and determined the species’ dietary composition and food preferences on Ulleung Island, South Korea, through field observations. From March 2016 to February 2018, the diversity of food items consumed was low, with the 10 most common plant species (from a total of 33) accounting for over 80%. Food availability varied depending on plant abundance, but this influence was minimized because of factors such as delayed fruit ripening. Drupes were the most favored food items (60–68%) but were replaced by nuts and weed seeds during the spring and winter months. Dietary composition and food preferences were related to the abundance of food items based on their phenology, but a steady, high preference forAphananthe asperawas observed throughout the study period. The abundance ofPrunus takesimensisin June was correlated with changes in the Black Wood Pigeon population. This study is the first to assess the feeding ecology of Black Wood Pigeons using field observations and suggests that the availability of different food items affects population changes on the East Asian Pacific islands.
Synthesis and Physical Property Measurements in Misfit Transition Metal Dichalcogenide (SbS)1.16TaS2
Authors: Doyama S , Ohta S , Sakata H 
Published: August 2020

Abstract
We report the single crystal growth and superconducting transition of a misfit layered compound (SbS)1.16TaS2. We succeed in the single crystal growth with flux method. The electrical resistivity measurements revealed the superconducting transition temperature of this material as 2.9 K, which was consistent with the previous research. Scanning tunneling microscopy measurements show two kinds of surfaces corresponding to TaS2 and SbS layers, indicating successful growth of the single crystal consist of stacking of these layers.
Local density of States in Two-Dimensional Nano-Structured Superconducting Systems with Superconductor-Normal Metal Interfaces
Authors: Fukui Saoto , Wang Zhen , Kato Masaru 
Published: August 2020

Abstract
In nano-structured superconductors, it is important to consider a discreteness of energy levels instead of continuous energy levels due to the quantum confinement effect. This discreteness causes an appearance of many peaks in a density of state (DOS). In this paper, the effect of the discreetness of energy level or the effect of the quantum confinement on the DOS in superconducting systems with superconductor / normal metal (S/N) interfaces are focused. In particular, in nano-sized finite systems, a local density of state (LDOS) becomes strongly spatial dependent because of non-uniform spatial distributions of a gap energy and a pair amplitude. We investigate the pair amplitude and the LDOS by solving the Bogoliubov-de Gennes equations self-consistently. The proximity effect leads to a penetration of the pair amplitude into the normal metal region. Then, the pair amplitude in the normal metal decays non-monotonously because of the effect of the nano-sized finite system. On the other hand, the spatial-averaged LDOS plots as a function of the energy have many peaks in both superconductor and normal metal regions. Also, a contribution of the normal metal to the superconductor causes an appearance of peaks of the LDOS at the energy below the gap energy. In the SNS junction, when width of the normal metal increases, these peaks at the energy below the gap energy appear clearly.
31P NMR studies of an iron-based superconductor Ba0.5Sr0.5Fe2(As1−x
P
x
)2 with T
c = 29 K
Authors: Itoh Yutaka , Adachi Seiji 
Published: August 2020

Abstract
We report 31P NMR studies of an oriented polycrystalline superconductor of Ba0.5Sr0.5Fe2(As1−x
P
x
)2 with x ∼ 0.4 (T
c = 29 K) at T = 14−325 K and B
0 = 1 and 5 T. The 31P Knight shift Kab
at B
0 ⊥ c shows a nearly T-independent uniform spin susceptibility above T
c and a spin singlet decrease below T
c. The 31P nuclear spin-lattice relaxation rate 1/T
1 shows an asymptotic behavior of a + bT (a and b are constants) at T > 100 K and the minimum at 40 K with an upturn toward T
c. The a term in 1/T
1 indicates the presence of two-dimensional antiferromagnetic spin fluctuations. The negative θ = −15 K of the Curie-Weiss-type antiferromagnetic spin susceptibility

χ
(
Q
)
∝

1
/

(
T
+
θ
)

in the analysis of 1/T
1
T suggests antiferromagnetic instability in the superconducting state. Discussions are made from the self-consistent renormalization (SCR) theory for the spin fluctuations with interlayer correlation.
Chemical pressure effect of the electron-doped FeSe films with an electric double-layer-transistor structure
Authors: Shikama N , Sakishita Y , Nabeshima F , Maeda A 
Published: August 2020

Abstract
We investigated chemical pressure effect of the electron-doped FeSe1−x
S
x
and FeSe1−y
Te
y
on LaAlO3 (x ≤ 0.25, y ≤ 0.5) with the electric double layer transistor structure. T
c of all the FeSe1−x
S
x
and FeSe1−y
Te
y
films except y = 0.5 is increased by doping electron with gate voltage V
G = +5 V. T
c of the electron-doped FeSe1−x
S
x
and FeSe1−y
Te
y
is decreased monotonically by substituting Se for both S and Te. The behavior is similar to those of the intercalated FeSe1−x
S
x
and FeSe1−y
Te
y
and the electron-doped FeSe0.5Te0.5 with the solid-ion-conductor field-effect transistor structure, but quite different from that of the pristine FeSe1−x
S
x
and FeSe1−y
Te
y
. This difference is considered to originate from the difference of the Fermi surface topology, which suggests that the superconducting mechanism of the electron-doped FeSe is different from that of the pristine FeSe.
Anion height dependence of critical current densities for Fe Te1-x Sex bulk single crystals
Authors: Miyaki K , Miura O , Mizuguchi Y 
Published: August 2020

Abstract
We have fabricated FeTe1-xSex high quality bulk single crystals. The crystals with different composition of x = 0.375, 0.4, 0.45, 0.46 and 0.475 were prepared by the melting method with two stage heat treatment. The crystal structure and superconducting properties were evaluated. Temperature dependence of magnetization showed that low-T
c region exists inside the crystals. Critical temperature T
c was the highest value of 14.3 K for the crystal with x = 0.45. Critical current densities J
c under the magnetic fields parallel to the c-axis at 4.2 K achieved 1.52 and 0.72 × 105 A / cm2 at 0 T and 5 T respectively for the crystal with x = 0.4. The crystal lattice parameters were examined by Rietveld refinement. The anion height from Fe layer was calculated using the obtained parameters. We investigated the anion height dependence of T
c and J
c and mentioned an important role of excess Fe about the magnetic flux pinning.
Effects of Point Defects Introduced by Co-doping and Proton Irradiation in CaKFe4As4
Authors: Kobayashi Y , Pyon S , Takahashi A , Tamegai T 
Published: August 2020

Abstract
Introduction of point defects into superconductors through proton irradiation enhances their critical current density (J
c). Similarly, chemical doping can also produce point defects, leading to the enhancement of J
c. Iron-based superconductors (IBSs) have been investigated as promising materials for practical applications because of their large J
c at high magnetic fields and temperatures. Recently, another promising IBS CaKFe4As4 (1144-type) was found, and attracts much interest due to its characteristic feature such as stoichiometric superconductivity and the presence of novel planar defects. We have grown single crystals of Co-doped CaKFe4As4 and clarified the effect of chemically-introduced point defects on J
c. We also introduced point defects through 3 MeV proton irradiation, and compared the effect of point defects to J
c.
Unconventional properties of high-temperature superconducting cuprates
Authors: Nishi Kazuhisa 
Published: August 2020

Abstract
In spite of much interest in various unconventional properties of superconducting cuprates such as the anisotropic superconductivity, the pseudogap state, the competing state in the underdoped region, strange metal in normal state, and anomalies in the optical sum rules etc, its microscopic mechanism still remains unsolved issues. Here these properties are considered using our recently proposed theory emphasizing that the electronic state of superconductors can be described by doping-dependent composite fermions. It is found that the anisotropy of the superconductive gap and the pseudogap are evaluated, the competing states is derived by mixed states model, and that T-linearity of resistivity and the anomaly of optical sum rules in the nearly optimal doping can be derived from considering the interplay between the composite fermion bands. It is also suggested that a crossover separating the strange metal and the normal metal in the overdoped region can be explained by the coupling effect of composite fermions
Progress in High-Speed Spin Testing of Superconducting Wire and Tapes for High-Field NMR Magnet Qualification
Authors: Voccio J. , Rueckert F. J. , Curtsmith P. , Favazza C. J. , Boyle J. , Franchi M. , Allen C. , Tetreault N. , Munson L. , Nedbal V. , Weekes-Tulloch A. 
Published: August 2020

Abstract
This paper summarizes the status of a 3-year, NIH-funded research project to study the strength of high temperature superconductors under high circumferential hoop stress, in order to qualify these materials for high-field (> 1 GHz-class NMR magnets. The unique approach presented here is to spin test coils at high rotational speeds, approaching 100,000 rpm, in order to induce the necessary hoop stress. Thermal strain compatibility between the Bi-2212 wire and Inconel wire has been qualified, including thermal cycling. Assembly and testing of the first low-speed (< 30,000 rpm) rotor is now in process, and the design of second, higher speed (> 60,000 rpm) rotor, is also underway.
Peculiarities of dissipative phenomena in coated YBCO tapes carrying constant current during flux creep
Authors: Romanovskiy V. R. 
Published: August 2020

Abstract
The effect of the flux creep on the dissipation phenomena in tapes based on YBCO leading to the essentially non-linear voltage-current characteristic of a superconductor is discussed. The obtained results are compared to the calculations made in the framework of the existing thermal stabilization theory based on the model assuming a jump transition from a superconducting state to a normal one. It is shown that the latter model incorrectly describes the dissipation modes, first of all, in a temperature range up to the critical temperature of the superconductor. It is proved that the type of nonlinearity of voltage-current characteristics has a significant effect on the dissipative phenomena in tapes in this temperature region. As a result, the allowable currents stably flowing in superconducting tapes may be higher than a priory defined critical current determined for continuously rising voltage-current characteristic. Correspondingly, the critical current of high-Tc superconducting tapes, which is determined using continuously increasing voltage-current characteristic, has no physical meaning. Therefore, fundamentals of the thermal stabilization theory must consider the real temperature dependence of the dissipated energy in high-Tc superconducting tapes, which depends on the nonlinearity of their voltage-current characteristic.
3D Numerical Study on Magnetization Losses in Twisted Soldered-Stacked-Square (3S) HTS Wires Based on Homogenized Models
Authors: Yao L P , Lv Y Y , Gu F , Zhong L H , Duan X H , Song M , Li L , Li Z Y , Hong Z Y , Jin Z J 
Published: August 2020

Abstract
Magnetization loss is an important parameter in the application of high temperature superconductivity (HTS) power devices. In order to reduce magnetization losses, a novel soldered-stacked-square (3S) HTS wire with 1 mm width is firstly proposed and manufactured by our group. In previous work, numerical and experimental results have shown the magnetization loss in the 3S wire is one order smaller than that in the original 4 mm tape under perpendicular magnetic field. However, large eddy current loss and coupling loss will be generated under parallel field. Therefore, to further reduce the magnetization loss, the 3S wire has been twisted and investigated numerically in this paper. Firstly, two-dimensional (2D) numerical models are built for calculating the magnetization loss in untwisted 3S wires. To simplify the computation, a homogeneous bulk-like model is built which does not include the individual tapes of stack. The results show that the losses calculated by the homogenized model is similarly equal to the original results. Based on this, the homogeneous technique is further applied in three-dimensional (3D) numerical models of the twisted 3S wire. The results indicate that the homogenized model could make a good predict for the losses in twisted wires. What’s more, the magnetization losses in twisted wires is compared with those in untwisted wires to verify that twisting process could actually reduce the magnetization loss of the novel superconducting wire.
Fabrication of (Ba,Na)Fe2As2 round wires and tapes using HIP process
Authors: Miyawaki D , Pyon S , Awaji S , Kajitani H , Koizumi N , Kito H , Ishida S , Yoshida Y , Tamegai T 
Published: August 2020

Abstract
We fabricated round wires and tapes of (Ba,Na)Fe2As2 using hot isostatic press (HIP) process, and evaluated their critical current density (Jc
). Polycrystalline powders were synthesized by two methods by mixing raw materials in a planetary ball mill or by using pre-synthesized precursors (BaAs, NaAs, Fe2As). Transport Jc
of best wire reached 95 kA/cm2 under self-field and 40 kA/cm2 at 100 kOe. We also fabricated HIP tapes using the same powder and discuss their detailed characterizations. In particular, X-ray diffraction is extensively applied to the evaluation of the degree of texturing of the tape, and discuss its relationship with J
c.