In this paper, nitration of 2,2′-diphenic acid was studied and two aromatic carboxylic acids containing two and four nitro groups, respectively, were synthesized and characterized through elemental ...analysis, IR spectra, respectively. Crystal structure of 4,4′-dinitro-2,2′-diphenic acid and 4,4′,6,6′-tetranitro-2,2′-diphenic acid was determined by X-ray single crystal diffraction and their thermal decomposition have been carried out through differential scanning calorimeter analyses at a heating rate of 10°C/min. The results indicate that the compounds have high heat-resistant stability.
A novel coordination polymer Co
5
(OH)
2
(dnbpdc)
4
(H
2
O)
6
·16H
2
O (
1
) (dnbpdc = 6,6′-dinitro-4,4′-biphenyldicarboxylic acid) is obtained from a hydrothermal reaction. The structure of complex
...1
is characterized by elemental analysis, IR spectroscopy, and single crystal X-ray diffraction analysis. The title compound (C
56
H
70
Co
5
N
8
O
56
,
M
r
= 2045.85) crystallizes in the triclinic space group
P
-1 with
a
= 11.9349(2) Å,
b
= 12.1895(2) Å,
c
= 15.420(2) Å, α = 109.390(7)°, β = 94.786(1)°, γ = 108.027(9)°,
V
= 1968.4(4) Å
3
,
Z
= 1,
D
c
= 1.726 g/cm
3
,
F
(000) = 1045, μ(Mo
K
α
) = 1.154 mm
–1
,
T
= 133(2) K, the final
R
= 0.0316 and
wR
= 0.0692 for 7032 observed reflections with
I
> 2σ(
I
). The coordination polymer is built of a pentanuclear Co(II) cluster, four dnbpdc ligands, two hydroxyl groups, six coordination water and sixteen crystal water molecules. Ligand oxygen atoms exhibit three types of coordination modes (monodentate,
syn-syn
bridging bidentate and bridging tridentate). Moreover, the infinite three-dimensional supramolecular network is generated by coordination and hydrogen bonds. The thermal stability of complex
1
is evaluated by differential scanning calorimetry and thermogravimetric analysis.
Herpes zoster and postherpetic neuralgia occur more often with increasing age. In this controlled trial among 38,546 adults 60 years of age or older, vaccination with a live attenuated ...varicella–zoster vaccine reduced the incidence of postherpetic neuralgia by 66.5 percent (as compared with placebo) and the incidence of herpes zoster by 51.3 percent.
In adults 60 years of age or older, vaccination with a live attenuated varicella–zoster vaccine reduced the incidence of postherpetic neuralgia by 66.5 percent (as compared with placebo) and the incidence of herpes zoster by 51.3 percent.
Herpes zoster, or shingles, is characterized by unilateral radicular pain and a vesicular rash that is generally limited to a single dermatome.
1
,
2
Herpes zoster results from reactivation of latent varicella–zoster virus (VZV) within the sensory ganglia.
3
,
4
The incidence and severity of herpes zoster increase with advancing age; more than half of all persons in whom herpes zoster develops are older than 60 years. Complications occur in almost 50 percent of older persons with herpes zoster.
3
–
5
The most frequent debilitating complication is postherpetic neuralgia, a neuropathic pain syndrome that persists or develops after the dermatomal rash has healed. . . .
Strategy I peanut plants are frequently subjected to iron deficiency when growing in calcareous soils, which contain high concentrations of bicarbonate. In calcareous soils under field conditions, it ...has been noted that chlorosis increases in severity after excessive rainfall or irrigation, but the chlorosis symptoms of peanuts are alleviated after waterlogged soils dry. A pot experiment was conducted simulating the chlorosis symptom observed in the field when peanut plants are exposed to fluctuating soil water content induced from rainfall or irrigation. We investigated the bicarbonate fluctuations resulting from adjustable soil water content (SWC) that could lead to bicarbonate-induced iron chlorosis of peanuts growing in calcareous soil. The experiments included three treatments of SWC (50% of water holding capacity (WHC), 80% of WHC, and 100% of WHC) under two levels of CaCO
3 concentrations (at 8.67% and 18.67%.) The results showed that the iron nutrition of peanuts could be regulated by different SWC at both CaCO
3 levels. Our observations indicate that iron deficiency chlorosis symptoms in peanuts grown in high soil water content were more severe, compared to those of peanuts in lower soil water content. A shift from high soil water content to lower soil water content could improve or eliminate the iron deficiency chlorosis symptom of peanuts. The HCO
3
− concentration in the peanut rhizosphere increased with increasing SWC and CaCO
3 content and it correlated with the level of soil water content. We suggest that variations in the soil water content could induce HCO
3
− concentration variation in the rhizosphere of peanuts. Consequently, the high HCO
3
− concentration, which is induced by a high water content in calcareous soil and a high CaCO
3 level, could inhibit the physiological response to iron deficiency of peanuts, resulting in iron deficiency chlorosis. The study indicates that a reasonable agricultural practice of irrigation and drainage should be considered to improve and prevent iron deficiency chlorosis of strategy I plants in calcareous soil.
In this work, we present the program MAELAS to calculate magnetocrystalline anisotropy energy, anisotropic magnetostrictive coefficients and magnetoelastic constants in an automated way by Density ...Functional Theory calculations. The program is based on the length optimization of the unit cell proposed by Wu and Freeman to calculate the magnetostrictive coefficients for cubic crystals. In addition to cubic crystals, this method is also implemented and generalized for other types of crystals that may be of interest in the study of magnetostrictive materials. As a benchmark, some tests are shown for well-known magnetic materials.
Program Title: MAELAS
CPC Library link to program files: https://doi.org/10.17632/gxcdg3z7t6.1
Developer’s repository link:https://github.com/pnieves2019/MAELAS
Code Ocean capsule: https://codeocean.com/capsule/0361425
Licensing provisions: BSD 3-clause
Programming language: Python3
Nature of problem: To calculate anisotropic magnetostrictive coefficients and magnetoelastic constants in an automated way based on Density Functional Theory methods.
Solution method: In the first stage, the unit cell is relaxed through a spin-polarized calculation without spin-orbit coupling. Next, after a crystal symmetry analysis, a set of deformed lattice and spin configurations are generated using the pymatgen library 1. The energy of these states is calculated by the first-principles code VASP 3, including the spin-orbit coupling. The anisotropic magnetostrictive coefficients are derived from the fitting of these energies to a quadratic polynomial 2. Finally, if the elastic tensor is provided 4, then the magnetoelastic constants are also calculated.
Additional comments including restrictions and unusual features: This version supports the following crystal systems: Cubic (point groups 432, 4̄3m, m3̄m), Hexagonal (6mm, 622, 6̄2m, 6∕mmm), Trigonal (32, 3m, 3̄m), Tetragonal (4mm, 422, 4̄2m, 4∕mmm) and Orthorhombic (222, 2mm, mmm).
References:
1 S. P. Ong, W. D. Richards, A. Jain, G. Hautier, M. Kocher, S. Cholia, D. Gunter, V. L. Chevrier, K. A. Persson, and G. Ceder, Comput. Mater. Sci. 68, 314 (2013).
2 R. Wu, A. J. Freeman, Journal of Applied Physics 79, 6209–6212 (1996).
3 G. Kresse, J. Furthmüller, Phys. Rev. B 54 (1996) 11169.
4 S. Zhang and R. Zhang, Comput. Phys. Commun. 220, 403 (2017).
•Software to calculate anisotropic magnetostrictive coefficients.•It also calculates anisotropic magnetoelastic constants.•Evaluation of magnetocrystalline anisotropy energy.•Calculations in an automated way by Density Functional Theory calculations.•It supports the main crystal symmetries in the research field of magnetostriction.
A brief review of the recent studies of the crystal and electronic structure and its stability under large strain-shear and tensile deformation of selected boron compounds, which have been predicted ...to be superhard on the basis of their high elastic moduli, is presented. It will be shown that in many cases, the materials undergo electronic instability and transformation to softer phases with a lower shear resistance than the original equilibrium structure. Therefore, high values of elastic moduli (“low compressibility”) do not guarantee high hardness. These results also challenge the recent “models of theoretical hardness of an ideal crystal”, which are based on the equilibrium electronic properties. It is shown that appropriately nanostructured materials open the way to the design of superhard materials.
To date, no study has investigated how prescription patterns change over time in Chinese patients with schizophrenia. This study aimed to determine psychotropic drug prescription patterns and the use ...of electroconvulsive therapy (ECT) for schizophrenia and their changes over time in a large psychiatric institution in Beijing, China.
The case notes of inpatients with schizophrenia were scrutinized to identify psychotropic drug prescription patterns and the use of ECT on November 10, 1999 and the same calendar day in 2008 and to compare the two surveys.
In 1999, 45.1% of inpatients with schizophrenia were on first-generation antipsychotic drugs (FGA), while 52.9% were on second-generation antipsychotic drugs (SGA). In 2008, the percentage of patients on FGAs decreased to 15.1%, while those on SGAs increased to 77.2%. The proportion of schizophrenia patients on mood stabilizers and antidepressants rose from 3.3% and 4.3% in 1999 to 18% and 9.5% by 2008, respectively. Use of ECT grew from 0.5% in 1999 to 5.6% by 2008. The proportion of schizophrenia patients not prescribed antipsychotic drugs changed from 5.6% in 1999 to 13.7% in 2008.
The prescription pattern of psychotropic drugs changes considerably over time, even in the same clinical setting. Mental health professionals need to keep up with changes in the prescription patterns of psychotropic drugs in order to serve their patients at the best possible level. The socio-economic reasons for not prescribing antipsychotic drugs to schizophrenia patients should be further explored.
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