Mineral Mineral Polymorphism: Polymorphism is the ability of a specific chemical composition to crystallize in more than one form. This generally occurs as a response to changes in temperature or pressure or both. The different structures of such a chemical substance are called polymorphic forms, or polymorphs. For example, the element carbon (C) occurs in nature in two different
polymorphism « Back to Glossary Index. A specific chemical composition that forms different minerals and different temperatures and pressures. Quartz has several different polymorphs, including coesite, tridimite, and stishovite. Synonyms: polymorph, polymorphs. Related Articles:
In materials science, polymorphism is the ability of a solid material to exist in more than one form or crystal structure.Polymorphism can potentially be found in any crystalline material including polymers, minerals, and metals, and is related to allotropy, which refers to chemical elements.The complete morphology of a material is described by polymorphism and other variables such as crystal
Polymorphism is a widely spread phenomenon in solid substances (Bernstein, 2002, Hilfiker, 2006, Brittain, 2009). A substance exhibits polymorphism when it can exist in more than one crystalline state. These various crystalline states consequently have a different thermodynamic potential, and therefore a different solubility in a given solvent.
Polymorphism, in crystallography, the condition in which a solid chemical compound exists in more than one crystalline form; the forms differ somewhat in physical and, sometimes, chemical properties, although their solutions and vapours are identical. The existence of different crystalline or molecular forms of elements is called allotropy, although it has been suggested that the meaning of
polymorphism The existence of two or more distinctly different forms (morphs) within a plant or animal species.An example is the caste system of social insects, in which there are workers, drones, and queens. This is an environmental polymorphism (see polyphenism), i.e. the differences are caused by environmental rather than genetic factors, in this case by the larvae receiving different types
Apr 10, 2018· In Earth Sciences Polymorphic minerals are two or more minerals that have the same chemical composition, but different crystal structures. For example, pyrite is isometric and marcasite is orthorhombic, but both are composed of iron sulfide. Sim...
Analysis of vitamin D receptor polymorphism and its relation to mineral bone density in the pathogenesis of osteoporosis A 'read' is counted each time someone views a publication summary
Summary: The discovery of new enzymes and functions has expanded the role of proteolysis beyond effects on structural integrity. (Leu10-->Pro) polymorphism, with bone mineral density and
Nov 19, 2014· Summary. Postmenopausal osteoporosis is the most common metabolic bone disease with important genetic factors. We evaluated the frequency of polymorphism 283G/A of the vitamin D 3 VDR gene receptor. The study included 800 women at the
INTRODUCTION. D uring the past 3 years, there has been substantial interest in the association of polymorphic vitamin D receptor (VDR) alleles and the risk of osteoporosis. 1 This field of research remains controversial because of the inconsistent findings in different studies. 2-4 Nonetheless, a preponderance of the evidence suggests that the VDR alleles defined by BsmI, ApaI, and TaqI
CiteSeerX Document Details (Isaac Councill, Lee Giles, Pradeep Teregowda):  Minerals with composition (Fe,Ni)2P, are rare, though important accessory phases in iron and chondritic meteorites. The occurrence of these minerals in meteorites is believed to originate either from the equilibrium condensation of protoplanetary materials in solar nebulae or from the later accretion and
CiteSeerX Document Details (Isaac Councill, Lee Giles, Pradeep Teregowda): Abstract Osteoporosis is a major public health problem for old people. Genetic factors are considered to be major contributors to the pathogenesis of postmenopausal osteoporosis. The vitamin D receptor (VDR) gene is a prominent candidate gene for the regulation of postmenopausal bone mass; however, despite exten-sive
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Polymorphism of the vitamin D receptor (VDR) gene has recently been shown to be related to bone mineral density, and also associated with hyperparathyroidism and risk of prostatic carcinoma. Considering that this might affect sarcoidosis, we investigated polymorphism of the VDR gene in 101 patients with sarcoidosis and 105 healthy control subjects.
Summary. High-pressure shock-wave data for hematite (Fe 2 O 3) and magnetite (Fe 3 O 4) are remarkable for the very large density increases (∼ 10 per cent at 100 GPa) associated with shock-induced transformation from the relatively close-packed corundum and spinel structures.The recently reported data of Jeanloz & Ahrens for wüstite (Fe 0.94 O) also reveal a major shock-induced phase
A novel T/C polymorphism (ATG to ACG) at the translation initiation site of the vitamin D receptor (VDR) gene, defined by Fok I restriction endonuclease, has been recently associated with variation in bone mineral density (BMD) and rates of bone loss in a group of postmenopausal Mexican‐American women.The presence of the restriction site, designated as f, allows protein translation to
Objective The hypothalamic–pituitary–adrenal axis setpoint and the glucocorticoid sensitivity of various tissues are at least partially genetically determined. We investigated the impact of glucocorticoid receptor (GR) gene polymorphisms, including the BclI, N363S, ER22/23EK and A3669G variants on bone turnover and/or mineral density (BMD) in patients with endogenous glucocorticoid excess.
In summary, our results show that carriers of the Leu allele for the Val432Leu polymorphism of the CYP1B1 gene have accelerated estrogen catabolism as indicated by significantly higher levels of urinary metabolites relative to those without the allele. This alteration resulted in lower BMD in
Polymorphism at the vitamin D receptor gene was examined in relation to bone mineral density (BMD) at spine, femur, and forearm in 86 monozygotic (MZ) and 39 dizygotic (DZ) adult female twins. All were white, 63 pairs (44 MZ, 19 DZ) were premenopausal, and 43 pairs (31 MZ, 12 DZ) were discordant for age at menopause or use of estrogen.
Summary. Objective. Type 2 deiodinase (DIO2)‐mediated thyroid hormone synthesis stimulates osteoblast activity and increases the expression of osteoblast differentiation markers, but there are no large cohort studies to identify the role of the DIO2 polymorphism in bone mineral density in humans.
Polymorphism of vitamin D3 receptor and its relation to mineral Summary Postmenopausal osteoporosis is the most common of the effect of vitamin D receptor genotype polymorphism upon the mineral density of bones has not been fully recog-nized yet.
Dec 15, 2014· Summary odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were estimated using random-effects models. LRP5 Ala1330Val polymorphism was associated with a significantly increased risk of fracture (OR = 1.10; 95% CI, 1.06-1.14; I 2 = 29%). We also found that this polymorphism increased fracture risk in Caucasians.
Identifying Minerals and Rocks Growth Habit and Polymorphism !!Growth habit:-!The characteristic crystal form of each mineral. !!Polymorphism: -!Some elements and compounds form two or more different minerals: -!C Graphite, Diamond -!CaCO3 Calcite, Aragonite -!FeS2 Pyrite, Marcasite -!SiO2 Quartz, Cristobalite !!
The C677T MTHFR polymorphism has been associated with lumbar spine and hip BMD. In older adults, the genetic effect has been reported in women only. However, in younger adults, this influence may onl...
In this study, we precisely constructed and transfected the overexpression and interference vectors in BFFs to evaluate the role of DLK1 gene on lipid metabolism in vitro. The expression of of DLK1 in the mRNA and protein level tended to reduce, and TGs were significantly increased in the pGPU6-shDLK1 group compared to the control group (p < 0.05).
May 15, 2014· • Il-2 is involved in b-cell activation and stimulates macrophages, nk cells, t cell proliferation, and osteoclast activity. • A polymorphism in the position -330 (T-G) of the il-2 gene promoter was identified by john et al. (1998). This polymorphism could be useful as a marker to diagnose susceptibility to inflammatory diseases. 59.
Apr 21, 2016· Polymorphism 1. Mr. Sagar Kishor Savale Department of Pharmaceutics [email protected] 2015-016 4/21/2016 Sagar Kishor Savale 1 1 2. List of contents:- 4/21/2016 Sagar Kishor Savale 2 1. Definition 2. Need to study polymorphism ( rational for selecting polymorph) 3. Types of polymorphism 4. How to differentiate them 5.
The low-density lipoprotein receptor-related protein 5 gene (LRP5) was identified to be linked to the variation in BMD in high bone mass pedigrees. Subsequent population-based studies of the association between the LRP5 gene and BMD have yielded conflicting results. The present study was aimed at examining the association between LRP5 gene and BMD by using meta-analysis.
Women with the CC genotype were found to have decreased serum calcium and reduced bone mineral density. Introduction: The CC genotype of the 13910 C/T polymorphism of the LCT gene is linked to lactose intolerance and low calcium intake. Methods: We studied 595 postmenopausal women, including 267 osteoporotic, 200 osteopenic, and 128 healthy
The transformation of CO2 into a precipitated mineral carbonate through an ex situ mineral carbonation route is considered a promising option for carbon capture and storage (CCS) since (i) the captured CO2 can be stored permanently and (ii) industrial wastes (i.e., coal fly ash, steel and stainless-steel slags, and cement and lime kiln dusts) can be recycled and converted into value-added
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