The pseudomalachite-ludjibaite-reichenbachite conundrum: OD description

2019 ◽  
Vol 57 (5) ◽  
pp. 571-581
Author(s):  
Emil Makovicky
Keyword(s):  
Crystal Structures ◽  
Current Knowledge ◽  
The Other ◽  
Crystal Chemical ◽  
Layer System ◽  
Coordination Polyhedra

Abstract Crystal structures of the three polymorphs of Cu5(PO4)2(OH)4, namely pseudomalachite, ludjibaite, and reichenbachite, can be described as being composed of rods perpendicular to their crystal-chemical layering. Two different sorts of rods can be defined. Type 1 rods share rows of Cu coordination polyhedra, forming a series of slabs. Slab boundaries and slab interiors represent alternating geometric OD layers of two kinds, with layer symmetries close to P21/m and , which make up two different stacking schemes of geometric OD layers in the structures of ludjibaite and pseudomalachite. Such OD layers, however, are not developed in reichenbachite. Type 2 rods are defined as having columns of PO4 tetrahedra in the corners of the rods. In the Type 2 slabs composed of these rods, geometric Pg OD layers of glide-arrayed tetrahedra alternate with more complex OD layers; in ludjibaite this system of layers is oriented diagonally with respect to the Type 1 OD layer system. Two different OD stackings of Type 2 OD layers form the ludjibaite and reichenbachite structures but not that of pseudomalachite. Thus, ludjibaite might form disordered intergrowths with either of the other two members of the triplet but reichenbachite and pseudomalachite should not form oriented intergrowths. Current knowledge concerning formation of the three polymorphs is considered.

Comparing the Arrangements of Governance and Sustainable Development in OECD Countries: Coupled or Decoupled?

2019 ◽  
Vol 34 (1) ◽  
pp. 99-117
Author(s):  
Huh Taewook
Keyword(s):  
Sustainable Development ◽  
Oecd Countries ◽  
The Other ◽  
Type Analysis ◽  
Ideal Types ◽  
Type 3 ◽  
Relationship Of ◽  
The Relationship

This study attempts to analyze to what extent governance and sustainable development (SD) empirically appear compatible in the thirtyfive OECD countries through the fuzzy-set ideal type analysis, and identify which ideal types appear coupled or decoupled, and then reveal which countries belong to the coupled types or to the decoupled types. In short, twenty-two countries (including Sweden (fuzzy score, 0.953), Denmark (0.920), Finland (0.914), Norway (0.911) in Type 1 (G*S, ‘strong G-S coupled countries’); and Turkey (0.906), Greece (0.833), Mexico (0.828) in Type 4 (g*s, ‘lite g-s coupled countries’) are in line with the accepted conventions regarding the compatible relationship between governance and SD. On the other hand, the rest of thirteen countries (including USA (fuzzy score, 0.815), Luxembourg (0.721), Australia (0.660) in Type 2 (G*s, ‘G-s decoupled countries’); and Slovenia (0.728), France (0.644), Czech Rep. (0.625) in Type 3 (g*S, ‘g-S decoupled countries’) may indicate that the relationship of governance and SD is in fact experiencing tensions in the national contexts. These findings are characterized by the substance (of SD) and procedure (of governance) divide. Considering the results, this study focuses on the idea of reflexivity or reflexive capacity.

Relational problems are not fully solved by a temporal sequence of statistical learning episodes

1997 ◽  
Vol 20 (1) ◽  
pp. 82-82 ◽  
Author(s):  
A. Vinter ◽  
P. Perruchet
Keyword(s):  
Implicit Learning ◽  
Statistical Learning ◽  
Temporal Sequence ◽  
The Other ◽  
Learning Mechanisms ◽  
Learning Research ◽  
The One

Clark & Thornton's conception finds an echo in implicit learning research, which shows that subjects may perform adaptively in complex structured situations through the use of simple statistical learning mechanisms. However, the authors fail to draw a distinction between, on the one hand, subjects' representations which emerge from type-1 learning mechanisms, and, on the other, their knowledge of the genuine abstract “recoding function” which defines a type-2 problem.

Analysis of the environment of beryllium, magnesium and alkaline earth atoms in oxygen-containing compounds

1999 ◽  
Vol 55 (2) ◽  
pp. 139-146 ◽  
Author(s):  
V. A. Blatov ◽  
L. V. Pogildyakova ◽  
V. N. Serezhkin
Keyword(s):  
Crystal Structure ◽  
Alkaline Earth ◽  
Organometallic Compounds ◽  
Alkaline Earth Metals ◽  
The Other ◽  
Crystal Chemical ◽  
Coordination Polyhedra ◽  
Coordination Numbers ◽  
Coordination Spheres

About 2100 inorganic and organometallic compounds containing beryllium, magnesium and alkaline earth atoms (M) were investigated with Voronoi–Dirichlet polyhedra (VDPs). It is shown that the coordination numbers (CNs) of the M atoms in MO n coordination polyhedra can be determined by means of VDPs without crystal-chemical radii. The distributions of the M—O distances in the coordination spheres of the M atoms are bimodal for M = Be or Mg and monomodal for the other alkaline earth metals. Beryllium and magnesium coordination polyhedra containing weak M—O contacts were classified by variants of their distortions. It is found that the volume of the domains of the Mg, Ca, Sr and Ba atoms is independent of their CNs at CN \ge 6 (up to 16 for barium). The possibility of using the model of deformable spheres to describe the crystal structure of the compounds investigated is suggested.

scholarly journals HOMOTYPIC COMPLEMENT-FIXING ANTIBODY IN MONKEYS INFECTED WITH TYPE 2 POLIOMYELITIS VIRUS BY THE ORAL ROUTE

1952 ◽  
Vol 96 (1) ◽  
pp. 55-58 ◽  
Author(s):  
Jordi Casals ◽  
Peter K. Olitsky ◽  
Albert B. Sabin
Keyword(s):  
Neutralizing Antibody ◽  
Oral Route ◽  
The Other ◽  
Human Beings ◽  
Serum Dilution ◽  
Cynomolgus Monkeys ◽  
Inapparent Infection ◽  
Order Of Magnitude

CF tests with Type 2 poliomyelitis antigen (MEF1) were performed on the pre- and postinfection sera of 20 cynomolgus monkeys which developed paralytic, non-paralytic, or inapparent infection following oral administration of a Type 2 strain of virus (Y-SK). All the monkeys developed neutralizing antibody, and 17 developed CF antibody in an original serum dilution titer of 1:4 or greater. The 3 monkeys which did not develop this level of CF antibody were in a group of 7 which died within 8 days after onset of paralysis. The CF titers were as high at 2 to 6 days after onset of paralysis in the other 4 moribund or dead monkeys as in the surviving animals tested 4 weeks after the first dose of virus and the CF titers were of the same order of magnitude in the groups with paralytic, non-paralytic, or inapparent infection. The Type 2 poliomyelitis CF titers developed in monkeys as a result of infection with homotypic virus were not greater than those found in human beings infected with heterotypic Type 1 poliomyelitis strains.

scholarly journals A Decomposable Branching Process in a Markovian Environment

2012 ◽  
Vol 2012 ◽  
pp. 1-24 ◽  
Author(s):  
Vladimir Vatutin ◽  
Elena Dyakonova ◽  
Peter Jagers ◽  
Serik Sagitov
Keyword(s):  
Survival Probability ◽  
Branching Process ◽  
The Other ◽  
Variable Environment ◽  
Markovian Environment ◽  
Constant Environment ◽  
Environment Type

A population has two types of individuals, with each occupying an island. One of those, where individuals of type 1 live, offers a variable environment. Type 2 individuals dwell on the other island, in a constant environment. Only one-way migration () is possible. We study then asymptotics of the survival probability in critical and subcritical cases.

scholarly journals A-loop interactions in Mer tyrosine kinase give rise to inhibitors with two-step mechanism and long residence time of binding

2020 ◽  
Vol 477 (22) ◽  
pp. 4443-4452
Author(s):  
Alexander Pflug ◽  
Marianne Schimpl ◽  
J. Willem M. Nissink ◽  
Ross C. Overman ◽  
Philip B. Rawlins ◽  
...  
Keyword(s):  
Tyrosine Kinase ◽  
Crystal Structures ◽  
Residence Time ◽  
Kinase Inhibitor ◽  
Structural Information ◽  
Kinase Domain ◽  
Phosphoryl Transfer ◽  
Mer Tyrosine Kinase

The activation loop (A-loop) plays a key role in regulating the catalytic activity of protein kinases. Phosphorylation in this region enhances the phosphoryl transfer rate of the kinase domain and increases its affinity for ATP. Furthermore, the A-loop possesses autoinhibitory functions in some kinases, where it collapses onto the protein surface and blocks substrate binding when unphosphorylated. Due to its flexible nature, the A-loop is usually disordered and untraceable in kinase domain crystal structures. The resulting lack of structural information is regrettable as it impedes the design of drug A-loop contacts, which have proven favourable in multiple cases. Here, we characterize the binding with A-loop engagement between type 1.5 kinase inhibitor ‘example 172’ (EX172) and Mer tyrosine kinase (MerTK). With the help of crystal structures and binding kinetics, we portray how the recruitment of the A-loop elicits a two-step binding mechanism which results in a drug-target complex characterized by high affinity and long residence time. In addition, the type 1.5 compound possesses excellent kinome selectivity and a remarkable preference for the phosphorylated over the dephosphorylated form of MerTK. We discuss these unique characteristics in the context of known type 1 and type 2 inhibitors and highlight opportunities for future kinase inhibitor design.

scholarly journals The role of glucocorticoid in the regulation of prostaglandin biosynthesis in non-pregnant bovine endometrium

2007 ◽  
Vol 193 (1) ◽  
pp. 127-135 ◽  
Author(s):  
Hwa-Yong Lee ◽  
Tomas J Acosta ◽  
Michiyo Tanikawa ◽  
Ryosuke Sakumoto ◽  
Junichi Komiyama ◽  
...  
Keyword(s):  
Mrna Expression ◽  
Estrous Cycle ◽  
Stromal Cells ◽  
Endometrial Tissue ◽  
The Other ◽  
Pcr Analysis ◽  
Factor Α

To determine whether glucocorticoids (GCs) play a role in regulating uterine function in cow, the present study examined the expression of mRNA encoding GC receptor (GC-R) α, 11β-hydroxysteroid dehydrogenase (11-HSD) type 1 and type 2, and the activity of 11-HSD1 in bovine endometrial tissue throughout the estrous cycle. We also studied the effects of cortisol on basal, oxytocin (OT)- and tumor necrosis factor-α (TNFα)-stimulated prostaglandin (PG) production. A quantitative real-time PCR analysis revealed that GC-Rα mRNA was expressed more strongly in the mid-luteal stage (days 8–12) than in the other stages. In contrast to GC-Rα mRNA expression, 11-HSD1 mRNA expression was greater in the follicular stage than in the other stages, whereas 11-HSD2 mRNA expression was lowest in the follicular stage. The activity of 11-HSD1 was greater in the follicular stage and estrus than in the other stages and was lowest in the mid-luteal stage. Cortisone was dose-dependently converted to cortisol in the cultured endometrial tissue. Although cortisol did not affect either the basal or OT-stimulated production of PGs in the cultured epithelial cells, the production of PGs stimulated by TNFα in the stromal cells was suppressed by cortisol (P < 0.05). Cortisol suppressed basal prostaglandin (PG)F2α without affecting basal PGE2 production in the stromal cells. The overall results suggest that the level of cortisol is locally regulated in bovine endometrium throughout the estrous cycle by 11-HSD1, and that cortisol could act as a luteoprotective factor by selectively suppressing luteolytic PGF2α production in bovine endometrium.

scholarly journals Autoimmune Hepatitis: Serum Autoantibodies in Clinical Practice

2021 ◽  
Author(s):  
Benedetta Terziroli Beretta-Piccoli ◽  
Giorgina Mieli-Vergani ◽  
Diego Vergani
Keyword(s):  
Autoimmune Hepatitis ◽  
Current Knowledge ◽  
Reference Method ◽  
Smooth Muscle Antibody ◽  
Autoimmune Sclerosing Cholangitis ◽  
Specific Autoantibody ◽  
Circulating Autoantibodies ◽  
International Autoimmune Hepatitis Group

AbstractCirculating autoantibodies are a key diagnostic tool in autoimmune hepatitis (AIH), being positive in 95% of the cases if tested according to dedicated guidelines issued by the International Autoimmune Hepatitis Group. They also allow the distinction between type 1 AIH, characterized by positive anti-nuclear and/or anti-smooth muscle antibody, and type 2 AIH, characterized by positive anti-liver kidney microsomal type 1 and/or anti-liver cytosol type 1 antibody. Anti-soluble liver antigen is the only AIH-specific autoantibody, and is found in 20–30% of both type 1 and type 2 AIH. Anti-neutrophil cytoplasmic antibody is frequently positive in type 1 AIH, being associated also with inflammatory bowel disease and with primary/autoimmune sclerosing cholangitis. The reference method for autoantibody testing remains indirect immunofluorescence on triple tissue (rodent liver, kidney and stomach), allowing both the detection of the majority of liver-relevant reactivities, including those autoantibodies whose molecular target antigens are unknown. Of note, the current knowledge of the clinical significance of autoantibodies relies on studies based on this technique. However, immunofluorescence requires trained laboratory personnel, is observer-dependent, and lacks standardization, leading to ongoing attempts at replacing this method with automated assays, the sensitivity, and specificity of which, however, require further studies before they can be used as a reliable alternative to immunofluorescence; currently, they may be used as complementary to immunofluorescence.

scholarly journals N-Acyl Amino Acids: Metabolism, Molecular Targets, and Role in Biological Processes

Biomolecules ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 822 ◽  
Author(s):  
Natalia Battista ◽  
Monica Bari ◽  
Tiziana Bisogno
Keyword(s):  
Amino Acids ◽  
Therapeutic Potential ◽  
Current Knowledge ◽  
Acid Amide ◽  
Molecular Targets ◽  
Naturally Occurring ◽  
Lipid Signal ◽  
Amide Derivatives

The lipid signal is becoming increasingly crowded as increasingly fatty acid amide derivatives are being identified and considered relevant therapeutic targets. The identification of N-arachidonoyl-ethanolamine as endogenous ligand of cannabinoid type-1 and type-2 receptors as well as the development of different–omics technologies have the merit to have led to the discovery of a huge number of naturally occurring N-acyl-amines. Among those mediators, N-acyl amino acids, chemically related to the endocannabinoids and belonging to the complex lipid signaling system now known as endocannabinoidome, have been rapidly growing for their therapeutic potential. Here, we review the current knowledge of the mechanisms for the biosynthesis and inactivation of the N-acyl amino acids, as well as the various molecular targets for some of the N-acyl amino acids described so far.

scholarly journals Insulin therapy in the hospital setting: a time for a change?

2016 ◽  
Vol 10 (1) ◽  
pp. 23
Author(s):  
Ada Maffettone ◽  
Massimo Rinaldi ◽  
Luigi Ussano ◽  
Andrea Fontanella
Keyword(s):  
Hospital Setting ◽  
The Other ◽  
Hospital Inpatient ◽  
Insulin Administration ◽  
Diabetes Treatment ◽  
Successful Management ◽  
Pros And Cons ◽  
Insulin Pens

The number of people with diabetes mellitus worldwide is expected to be more than double from 171 million in 2000 to 366 million in 2030. Approximately 25% of all hospital inpatient days are affected by diabetes. In Italy there are more than 12,000 hospitalizations excesses for 100,000 people per year, with a huge economic impact. Ever since its discovery in the 1920s, insulin has been the milestone of type 1 diabetes treatment and its use is increasingly necessary for the successful management of type 2 diabetes. Often patients believe that injecting insulin can be painful, inconvenient and embarrassing; generally they are afraid of gaining weight and of hypoglycemia. On the other side, physician’s concerns regarding insulin administration include potential dosing errors and patient non-compliance. Ever since its discovery in the mid-1920s, insulin was administered subcutaneously using a vial and syringe. In 1985 the first pen device was launched. Currently disposable insulin pens are the most used and preferred by patients in the daily use, but are not routinely used for diabetic inpatients. In this paper we will focus on the pros and cons of insulin administration with pens in the hospital setting.

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