Relevant bibliographies by topics / Polymorphic control

Academic literature on the topic 'Polymorphic control'

Author: Grafiati
Published: 10 December 2022
Last updated: 28 January 2023

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Journal articles on the topic "Polymorphic control"

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Kuzmin, V. S., V. V. Chernyshev, and A. I. Luttseva. "X-RAY POWDER DIFFRACTION IN QUALITY CONTROL OF MEDICINES." Bulletin of the Scientific Centre for Expert Evaluation of Medicinal Products 8, no. 3 (September 26, 2018): 158–61. http://dx.doi.org/10.30895/1991-2919-2018-8-3-158-161.

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X-ray powder diffraction is one of the methods used for detection and analysis of polymorphic forms of pharmaceutical substances. The article elucidates the concept of polymorphism, briefly explains physical characteristics of this phenomenon, conditions of polymorphic transformations and the prevalence of polymorphic forms among drug substances. It should be noted that polymorphism is observed in drug substances belonging to different pharmacologic classes. Polymorphic forms of the same drug substance have different solubility, melting point, resistance to oxidation and to other destructive processes, and, consequently, different surface properties which affect both the rate of absorption of the drug substances and their stability as components of dosage forms. This calls for the need to control the quality of drug substances for potential presence of polymorphic forms. The use of diffraction methods for examination of cryomodified forms of various biologically active compounds obtained by evaporation and subsequent precipitation at low temperatures resulted in obtaining polycrystalline substances with new properties. The article provides results of examination of crystalline modifications of phenazepam in the form of α- and β-polymorphs, tilorone, fabomotizole, zolendronic acid and dehydroepiandrosterone. It was demonstrated that the use of X-ray diffraction analysis for examination and quality control of polymorphic forms of drugs is a necessary component of identification testing.
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Ângelo, Marilene, Jennifer Jacon, Olimpia Maria Santos, Edith Cristina Cazedey, Rudy Bonfilio, Antônio Carlos Doriguetto, and Magali Benjamim de Araújo. "Occurrence of polymorphism in famotidine raw materials." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1563. http://dx.doi.org/10.1107/s2053273314084368.

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Polymorphs are compounds with the same chemical composition, however the molecules are arranged in at least two different ways in the solid state. Famotidine is a histamine H2-receptor antagonist inhibitor of gastric secretion and widely used in gastric and duodenal ulcer disease. Two polymorphs are described for famotidine, A and B. The polymorph A is the most thermodynamically stable form and polymorph B is the kinetically favored form being marketed because it presents greater pharmacological activity. The aim of this study was to evaluate the occurrence of famotidine polymorphs in five raw materials acquired from different suppliers. The reference standard (USP) was also analyzed. All samples were characterized by powder X-ray diffraction (PXRD), infrared spectrophotometry (IR-ATR) and differential scanning calorimetry (DSC). PXRD analysis enables us to identify form B in five raw material samples and in the reference standard (USP). However, one of the raw materials additionally shows the presence of polymorphic form A. The DSC and IR-ATR techniques were essential to identify the polymorphic forms of famotidine confirming the results obtained by PXRD. Since the presence of polymorphs can compromise the effectiveness and safety of medicines and there is no official methodology of analysis and control of polymorphism in famotidine raw materials, the polymorphic contamination found in this study are being further analyzed and their physicochemical properties are being evaluated.
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Wantha, Lek. "Kinetics of the Solution-Mediated Polymorphic Transformation of Organic Compounds." Current Pharmaceutical Design 24, no. 21 (October 15, 2018): 2383–93. http://dx.doi.org/10.2174/1381612824666180601093228.

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Polymorphism is a behavior of a substance to crystallize into more than one district crystal structures. Preferential formation of a polymorph depends strongly on the kinetics of the relevant mechanisms. Solutionmediated polymorphic transformation is an important mechanism in crystallization of organic compounds from solution. Knowing its kinetics allows us to understand the process and control the polymorphic formation. In this review, concepts, kinetics, and process modeling of crystallization and solution-mediated polymorphic transformation are examined and summarized.
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Yang, Yuxin, Jia Liu, Anna Hu, Ting Nie, Zeneng Cheng, and Wenjie Liu. "A Critical Review on Engineering of d-Mannitol Crystals: Properties, Applications, and Polymorphic Control." Crystals 12, no. 8 (August 1, 2022): 1080. http://dx.doi.org/10.3390/cryst12081080.

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d-mannitol is a common six-carbon sugar alcohol, which is widely used in food, chemical, pharmaceutical, and other industries. Polymorphism is defined as the ability of materials to crystallize into different crystal structures. It has been reported for a long time that d-mannitol has three polymorphs: β, δ, and α. These different polymorphs have unique physicochemical properties, thus affecting the industrial applications of d-mannitol. In this review, we firstly introduced the characteristics of different d-mannitol polymorphs, e.g., crystal structure, morphology, molecular conformational energy, stability, solubility and the analytical techniques of d-mannitol polymorphisms. Then, we described the different strategies for the preparation of d-mannitol crystals and focused on the polymorphic control of d-mannitol crystals in the products. Furthermore, the factors of the formation of different d-mannitol polymorphisms were summarized. Finally, the application of mannitol polymorphism was summarized. The purpose of this paper is to provide new ideas for a more personalized design of d-mannitol for various applications, especially as a pharmaceutical excipient. Meanwhile, the theoretical overview on polymorphic transformation of d-mannitol may shed some light on the crystal design study of other polycrystalline materials.
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Brady, John J., Brittney L. Argirakis, Alexander D. Gordon, Richard T. Lareau, and Barry T. Smith. "Polymorphic Phase Control of RDX-Based Explosives." Applied Spectroscopy 72, no. 1 (August 25, 2017): 28–36. http://dx.doi.org/10.1177/0003702817712259.

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The polymorphic phase of 1,3,5-trinitro-1,3,5-triazine (RDX) was examined as a function of mass loading, solvent, and sample deposition technique. When RDX was deposited at a high mass loading, the vibrational modes in the obtained Raman spectra were indicative of concomitant polymorphism as both the α-RDX and β-RDX phases were present. At low mass loadings, only β-RDX was observed regardless of solvent when using the drop cast crystallization method. However, α-RDX (the thermodynamically stable polymorphic phase observed with visible quantities of the explosive) was observed when RDX deposits were dry transferred. Observation of α-RDX was independent of the initial mass loading or the initial deposition solvent when using the dry transfer methodology. These data indicate that the use of the dry transfer preparation method can be used to successfully prepare RDX-based test articles with the α-RDX phase regardless of the solvent used to initially dissolve the RDX, the initial deposition technique, or the mass loading.
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Li, Keyao, Monalisa Roy, Madiha Nisar, Lawrence W.-Y. Wong, Herman H.-Y. Sung, Richard K. Haynes, and Ian D. Williams. "Control of 11-Aza:4-X-SalA Cocrystal Polymorphs Using Heteroseeds That Switch On/Off Halogen Bonding." Crystals 12, no. 10 (September 27, 2022): 1368. http://dx.doi.org/10.3390/cryst12101368.

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A family of: 1:1 cocrystals 11-Aza:4-X-SalA have been prepared from the potent anti-malarial compound 11-azaartemisinin with 4-halosalicylic acids. When X = 4-Cl, 4-Br and 4-I, two conformational polymorphs can be isolated in each case. Monoclinic type-I was found previously for parent 11-Aza:SalA (1) and 11-Aza:4-Br-SalA (3a) which have polar 21 stacks of molecular pairs with no short halogen bond contacts between stacks. Orthorhombic type-II is found for 4-Cl (3b) and 4-I (4b) from solution growth. This has a translational stack of molecular pairs involving a conformational change of the acid-lactam hetero-synthon and supramolecular association of stacks via halogen bonds. Notably, phase pure polymorph type-I can be formed for 4-Cl (3a) and 4-I (4a) by hetero-seeding with 11-Aza:SalA, whist conversely phase pure type-II for 4-Br (2b) can be formed using homo-seeding from liquid assisted grinding (LAG) product. This work demonstrates both the viability of engineering polymorphic cocrystal forms using hetero-seeds and the involvement of halogen bonds in helping to discriminate quite different polymorphic types.
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Mukhammadieva, Guzel F., T. G. Kutlina, D. O. Karimov, Ya V. Valova, P. V. Serebryakov, A. V. Melent’Ev, A. B. Bakirov, A. U. Shagalina, and E. F. Idiyatullina. "THE EVALUATION OF RISK OF DEVELOPMENT AND COURSE OF BRONCHIAL ASTHMA ON THE BASIS OF POLYMORPHISM OF GENE TNFA." Health Care of the Russian Federation 61, no. 3 (May 24, 2019): 128–32. http://dx.doi.org/10.18821/0044-197x-2017-61-3-128-132.

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The bronchial asthma is one of the most widespread multi-factorial diseases developing in interaction of environmental and genetic factors. The purpose of this study was to analyze association of polymorphism of gene TNFA with risk of development of bronchial asthma considering clinical form of disease. The polymerase chain reaction technique was applied to analyze polymorphic locus rs1800629 of gene TNFA in patients with bronchial asthma (n=133) and control group (n=195). The analysis of rate of polymorphism of gene TNFA established reliable increasing of rate of allele A in group of patients with bronchial asthma as compared with control sample. According the coefficient of chances ratio, the risk of development of bronchial asthma if there is allele A of polymorphic locus rs1800629 of gene TNFA increases more than twice (OR=2,53; 95% CI 1,45-4,43). At that, various firms of bronchial asthma have specific features in distribution of rates of genotypes of polymorphic locus rs1800629 of gene TNFA. It is demonstrated that among agents of genotypes GA of polymorphic modification of rs1800629 of gene TNFA patients with mixed form of bronchial asthma were found more frequently than among agents of genotypes GG. The obtained results provide ground to suppose that polymorphic modification of rs1800629 of gene TNFA shows certain damaging effect under various clinical forms of bronchial asthma.
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Labine-Romain, Mackenzie, Sabrina Beckmann, Mohan Bhadbhade, Saroj Bhattacharyya, Michael Manefield, Christopher E. Marjo, and Anne M. Rich. "Polymorphs of Neutral Red, a Redox-Mediating Phenazine in Biological Systems." Australian Journal of Chemistry 70, no. 9 (2017): 1032. http://dx.doi.org/10.1071/ch17141.

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Neutral red 1 is a heterocyclic phenazine that, as a crystalline solid, has been observed to accelerate microbial methane generation from coal. Scale-up to an industrial process will require large quantities of neutral red crystals, hence an understanding of any polymorphic behaviour is essential for careful control of this process. A room-temperature structure of 1 (Form I) has been reported previously, and this study describes a new polymorph (Form II) crystallising from aqueous solution at 50°C, or transforming from Form I over an incubation time of one week at 70°C. Single-crystal X-ray diffraction has been used to study the molecular arrangements and intermolecular interactions in the new polymorph, and compared with those found in the room temperature form. Both polymorphs have been characterised using Raman and infrared spectroscopy, and a synthetic mixture of polymorphs successfully imaged using Raman spectroscopy. Raman imaging is proposed as a quality control method for small quantities of sample to ensure the correct polymorph is produced as a feedstock for this new methanogenesis process.
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Czernek, Jiří, and Jiří Brus. "Polymorphic Forms of Valinomycin Investigated by NMR Crystallography." International Journal of Molecular Sciences 21, no. 14 (July 11, 2020): 4907. http://dx.doi.org/10.3390/ijms21144907.

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A dodecadepsipeptide valinomycin (VLM) has been most recently reported to be a potential anti-coronavirus drug that could be efficiently produced on a large scale. It is thus of importance to study solid-phase forms of VLM in order to be able to ensure its polymorphic purity in drug formulations. The previously available solid-state NMR (SSNMR) data are combined with the plane-wave DFT computations in the NMR crystallography framework. Structural/spectroscopical predictions (the PBE functional/GIPAW method) are obtained to characterize four polymorphs of VLM. Interactions which confer a conformational stability to VLM molecules in these crystalline forms are described in detail. The way how various structural factors affect the values of SSNMR parameters is thoroughly analyzed, and several SSNMR markers of the respective VLM polymorphs are identified. The markers are connected to hydrogen bonding effects upon the corresponding (13C/15N/1H) isotropic chemical shifts of (CO, Namid, Hamid, Hα) VLM backbone nuclei. These results are expected to be crucial for polymorph control of VLM and in probing its interactions in dosage forms.
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Gabdulkhaev, Mukhammet N., Marat A. Ziganshin, Aleksey V. Buzyurov, Christoph Schick, Svetlana E. Solovieva, Elena V. Popova, Aidar T. Gubaidullin, and Valery V. Gorbatchuk. "Smart control of calixarene polymorphic states." CrystEngComm 22, no. 42 (2020): 7002–15. http://dx.doi.org/10.1039/d0ce01070g.

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Dissertations / Theses on the topic "Polymorphic control"

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Kaewgun, Sujaree. "Synthesis and polymorphic control for visible light active titania nanoparticles." Connect to this title online, 2009. http://etd.lib.clemson.edu/documents/1252423855/.

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Turp, Sarah Ann. "Chemical control of the polymorphic phase boundaries in doped barium titanate." Thesis, University of St Andrews, 2013. http://hdl.handle.net/10023/3817.

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Barium titanate (BaTiO₃), a known ferroelectric material, is of great interest as a future lead-free piezoelectric if appropriately doped to tailor the electric properties for specific applications. This work focuses on the study and rationalisation of the dielectric properties of a series of A-site/B-site co-doped compositions: SrZrO3-BaTiO₃, CaZrO₃-BaTiO₃, LaScO₃-BaTiO₃ and GdScO₃-BaTiO₃. The effect of sintering conditions and microstructure on ceramics is shown to have a significant impact on the physical properties of these materials. Pellet inhomogeneity, air sensitivity in pre-calcined powders and the presence of parasitic grain boundary capacitances are all shown to have adverse effects on properties, including the magnitudes of relative permittivity and TC calculated from total capacitance data. These can be overcome by careful control of synthesis conditions. Dielectric spectroscopy measurements on the optimised materials show that increasing addition of SrZrO₃, CaZrO₃ or LaScO₃ causes the phase transitions between the various polymorphs of BaTiO₃ to coalesce. In each case TC is reduced whilst each of the other phase transitions is shifted to higher temperatures, until the coalescence temperature is reached. When doped with GdScO₃ TC is observed to fall, but so too are the rhombohedral/orthorhombic and orthorhombic/tetragonal transitions, resulting in a stabilisation of the tetragonal polymorphic phase. This is suggested to result from an antipolar displacement of small Gd₃₊ ions, resulting in 8-coordinate ion and stabilisation of the tetragonal polymorph. The addition of dopant species is shown to result in two different high temperature conduction regimes. Both mechanisms are observed within single compositions over different temperature ranges. It is suggested that this is due to a change between n- and p-type electronic conduction processes or mixed ionic/electronic processes. Finally, it is shown that trends observed in changes to TC cannot be accounted for by simple and widely used size-based arguments alone, but requires consideration of cation size variance and charge dilution effects in order to fully understand the impact on TC of dopant addition.
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McLure, Craig Anthony. "Duplication and polymorphism with particular reference to regulators of complement activation." University of Western Australia. Centre for Molecular Immunology and Instrumentation, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0103.

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[Truncated abstract] For the convenience of the reader, detailed figures and tables have been enlarged and compiled in Appendix 2, at the end of this thesis. This thesis is presented as an approach to identify, annotate and detect genomic duplication and polymorphism within large genomic regions. To demonstrate this, I have used as a model, the genomic region known as the Regulators of Complement Activation (RCA). The RCA complex is located on the long arm of chromosome 1 at position 1q32 and is a reservoir of complement regulatory proteins. The genes of the RCA share many similarities implying that all have arisen through multiple complex duplication events. My analysis of this region in the following chapters demonstrates the complexity of this duplication and identifies the many functional units within the RCA. It was my aim at the beginning of these studies to demonstrate an approach that could define the Ancestral Haplotypes (AHs) of the RCA gene cluster. To do this, extensive genomic analysis was required and the ever-increasing availability of genomic sequence has made this thesis possible. Each of the chapters serves to address the following aims set out at the beginning of this thesis: 1. Further characterise the relationship between the genes (Complement Control proteins-CCPs) and domains of the Regulators of Complement Activation (RCA). 2. Identify and examine the duplicated elements within the RCA. - 6 - 3. Examine the effects of retroviruses and other insertions and deletions (indels) in generating the divergence of duplicated genes. 4. Investigate the applicability of the Genomic Matching Technique (GMT) to define AH within the region. 5. Examine association of AHs with CCP implicated diseases. 6. Determine the GMT applicability in non-human species
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Abu, Bakar Mohd R. "Process analytical technology based approaches for the monitoring and control of size and polymorphic form in pharmaceutical crystallisation processes." Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/6436.

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Pharmaceutical crystallisation operation is often critical because it determines product properties, such as the crystal size distribution (CSD) and polymorphic form, that can influence the subsequent downstream operations and the product therapeutic performance. Driven by the United States Food and Drug Administration s (FDA) Process Analytical Technology (PAT) initiative and the Quality-by-Design (QbD) concept, the development of control approaches, which can improve the manufacturing of products with desired properties, has become of significant interest. This thesis presents the development and application of PAT-based approaches for the monitoring and control of pharmaceutical crystallisation operations that will ensure consistent production of active pharmaceutical ingredients (APIs) with the desired size and polymorphic form. The approaches utilised Lasentec focused beam reflectance measurement (FBRM) and attenuated total reflectance ultraviolet (ATR-UV) spectroscopy as the in situ monitoring and control tools. Crystallisations of the APIs that posses multiple polymorphs are both critical and challenging. This was illustrated in this work by the crystallisations of sulfathiazole polymorphs using literature methods. The processes were monitored using FBRM and ATR-UV spectroscopy to define the design range of the process parameters. The defined range could be used as a recipe to reproduce the same quality of crystals. The obtained crystals were characterised using various techniques (optical microscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetry, hot-stage microscopy (HSM), Fourier Transform infrared spectroscopy and powder X-ray diffractometry) to assess the success of the crystallisation processes. The combined results of the techniques showed that all methods were able to produce the desired pure polymorphs. As a contribution to the technique of investigating polymorphism, a combined approach of DSC-HSM with image analysis, was introduced. Results show the capability of the approach to provide a unique insight into the polymorphic transformations and thermal behaviour exhibited by the model compound. The novel direct nucleation control (DNC) approach was introduced to control the CSD. The approach utilises information on nucleation, provided by FBRM, in a feedback control strategy that adapts the process variables, so that the desired CSD of product is achieved. It also provides in situ fines removal through the operating policy, rather than having additional equipment and external recycle loops. The approach does not require concentration measurement and has the advantage of being a model-free approach, requiring no information on nucleation or growth kinetics in order to design an operating curve; the system automatically and adaptively detects the boundary of the operating curve. Experimental results, using glycine in water-ethanol mixture as a model system, show the benefits of DNC to produce larger crystals with narrower CSD compared to uncontrolled operations. The capability of seeded cooling crystallization with temperature cycling approach to control crystal size uniformity and polymorphic purity was evaluated. Using sulfathiazole in n-propanol and in water as model systems, the method was found to accelerate the growth and enhance the size uniformity of the crystals, in comparison with runs using a linear temperature profile, by promoting Ostwald ripening. Although the approach is conceptually capable of controlling polymorphic purity of a system, the effect of solvent-mediated nucleation/growth can be more dominant, as shown by the results of the experiments. The insights into this behaviour of sulfathiazole crystals were captured very well by the FBRM. The study also demonstrated the successful use of a simple non-linear function as a calibration model to relate temperature and absorbance data, obtained using the ATR-UV spectroscopy, to solute concentration during the crystallisation process. The effect of temperature cycling, performed during seeded cooling crystallisation, on the surface features of sulfathiazole crystals was investigated using FBRM and ex situ optical microscopy, SEM and atomic force microscopy. It was observed during the initial stage of the process, the heating phases produced crystals with smooth surfaces, whilst the cooling phases promoted growth of features on the surfaces. These changes detected by the FBRM as an increase in the number of coarse counts during heating and a drop during cooling. Laser beam spreading caused by the surface roughness, and signal/chord splitting due to sharp edges are offered as an explanation for the FBRM results. This shows the capability of the FBRM to provide useful information about the changes on the surface of the crystalline products. The information can be used to avoid problems in the downstream operations, or in the final product property due to variations in flowability and friability, which are influenced by the surface property.
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Simone, Elena. "Application of process analytical technology (PAT) tools for the better understanding and control of the crystallization of polymorphic and impure systems." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/20098.

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This work presents a comprehensive study on the application of PAT tools to study, monitor and control polymorphism during batch cooling crystallization processes. For the first time, the same techniques were used to control and adjust polymorphic purity of the solid phase but also to investigate the relation between chemical equilibrium in solution and polymorphic outcome of cooling crystallization. Crystallization is an important unit operation used as separation and purification technique. It is widely employed in the pharmaceutical, chemical, agrochemical, food and cosmetics industries but also in the electronic, metallurgic and material industries. More than 90% of the APIs on the market are produced by crystallization, therefore, monitoring and control this process is fundamental to ensure the quality of the final product. The implementation of process analytical technology (PAT) tools during the development stage of APIs has largely helped in better understanding and optimizing both batch and, more recently, continuous crystallization. Polymorphism is the capacity of a compound to crystallize in more than one different crystalline structure, which can have different properties such as density, melting point, bioavailability and solubility. The choice of solvent, pH, kinetic conditions and presence of impurities has very strong effect on the polymorphic outcome of a cooling crystallization in solution. Understanding this phenomenon as well as being able to monitor and control it during industrial crystallization is one the biggest challenges for pharmaceutical industries.
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Donahue, Michael J. "Polymorph characterization and control /." View online ; access limited to URI, 2007. http://0-digitalcommons.uri.edu.helin.uri.edu/dissertations/AAI3276988.

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Lai, Tsai-Ta Christopher. "Control of polymorphism in continuous crystallization." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104203.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemical Engineering, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references.
Continuous manufacturing has gained significant interest in recent years as the ultra-lean mode of pharmaceutical production. Albeit the increasing number of studies on the process dynamics in continuous crystallization, in particular in yield improvement and impurity separation, the research community lacks the systematic understanding of the control of polymorphism in continuous crystallization. Variations in the polymorphism of the active pharmaceutical ingredient can undermine the bioavailability and the downstream processability of the drug substance. Thus, precise control of the drug polymorphism is pivotal for delivering quality drug products to the patients. In this thesis work, we aimed to develop a series of steps forward in understanding the polymorph dynamics in continuous crystallization, notably in mixed-suspension, mixed-product removal (MSMPR) crystallization. We first elucidated the major intrinsic and extrinsic factors which govern the process polymorphism in both monotropic and enantiotropic polymorphic compounds. Using the monotropic L-glutamic acid as the model compound, two temperature regimes each with distinctive kinetic and thermodynamic characteristics were identified. It is found that at high temperatures, the polymorph dynamics is mediated by the relative thermodynamics of the polymorphs. The most stable form is likely to be the dominant form at steady state. On the other hand, at low temperatures, the interplay of the crystal growth and nucleation kinetics is found to play an important role in determining the final polymorphism. Similar results were identified in the enantiotropic p-aminobenzoic acid system where three temperature regimes were identified. The additional regime is located near to the transition temperature where the chemical potential of the two polymorphs are identical. The steady state polymorphism is thereby determined by the kinetic energy barriers for the crystallization of the polymorphs. The study of polymorphism was also conducted in cooling-antisolvent crystallization and the effect of solvent composition on the polymorph dynamics was studied. In addition, the dynamic pathways connecting the startup states to the metastable steady states and the stable steady states were determined. The polymorphic transition between these steady states was observed and analyzed. The fundamental understanding of the kinetic competition and the governing dynamics in polymorphic crystallization forms the backbone for developing the polymorph control strategies in this thesis. Based on the polymorph dynamic studies, we designed MSMPR cascade systems to control the process polymorphism. In addition, systematic procedures are established to facilitate the design and optimization of continuous crystallization with the objectives to control polymorphism, optimize process yield and achieve the target crystal size distribution. The operational window is determined within which these control objectives are achieved. As there are increasing interests in transitioning pharmaceutical manufacturing from batch to continuous processing, the results in this thesis should develop a substantial position in the body of scientific literature.
by Tsai-Ta Christopher Lai.
Ph. D.
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Hahn, Patrick Daniel. "Social control of polymorphism in Zootermopsis." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185916.

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The sex-specific effects of reproductives and of soldiers on the reproductivity (i.e., tendency to develop into replacement reproductives) of pseudergates of Zootermopsis nevadensis were studied. Reproductives inhibit reproductivity in pseudergates of their own sex only. Reproductives neither inhibit nor stimulate reproductivity in pseudergates of the opposite sex. Reproductives do not require the presence of a reproductive of the opposite sex to stimulate them to inhibit reproductivity in pseudergates. Soldiers had no effect on the reproductivity of pseudergates. The effects of group size and of the presence or absence of reproductives on the development of last-stage nymphs of Z. nevadensis were studied. The size of experimental groups had no effect on the rates of stationary molts or alate molts, suggesting that the correlation between colony size and the onset of alate production in nature may be spurious. The presence or absence of reproductives had no effect on the rate of stationary molts or alate molts, suggesting that in Z. nevadensis neither group size nor the presence of reproductives has any direct effect on alate determination. It is suggested that in Z. nevadensis a form of nutritional castration can delay the onset of alate development; that is to say, that the onset of alate development is determined by the ratio of nutrient-gathering castes to nutrient-receiving castes in the colony. I have found what I believe to be an extraordinary example of deception in Z. nevadensis and Zootermopsis angusticollis. This is the first reported example of caste mimicry in a social insect, and may explain why supernumerary replacement reproductives are common in Z. nevadensis and Z. angusticollis but not in Zootermopsis laticeps. The compositions of 41 field-collected colonies of Zootermopsis were given and the data were analyzed for trends. Most notably, supernumerary replacement reproductives were common in Z. nevadensis and in Z. angusticollis but have never been found in Z. laticeps, by us or by anybody else. These findings are in accordance with our hypothesis of "caste mimicry" in Z. nevadensis and Z. angusticollis.
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Yang, Xiaochuan Ph D. Massachusetts Institute of Technology. "Polymorphism control and the formation of organic molecular nanocrystals." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/91067.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemical Engineering, 2014.
Cataloged from PDF version of thesis.
Includes bibliographical references.
The formation of organic molecular nanocrystals is a topic of great interest in the pharmaceutical industry because of the potential increase in dissolution rate and solubility of organic crystals below 1 ptm and their potential use in drug products. Previous investigators have developed various methods to produce them; however, breakage, high supersaturation and high intensity mixing are often involved in those methods, producing amorphous solids and if crystalline solid is obtained making control of desired polymorphs difficult. The aim of this thesis is to: (1) Evaluate practical methods to produce organic molecular nano-crystals of the desired form; (2) determine the change in crystal solid properties with size; (3) develop a better fundamental understanding of nucleation kinetics during concomitant nucleation of polymorphs. The first approach tried used bi-functional Self-Assembled Monolayers (SAMs) substrates. Using mefenamic acid as the model compound, micro-sized and nano-sized crystals were obtained with controlled polymorphs and narrow size distributions. By tuning experimental conditions and surface chemistry, exclusive production of one polymorph was demonstrated as well. On the 1 ptm gold islands a single crystal was obtained on each of the islands with a crystal size of ~ 300 nm. The second approach is crystallization under nano-sized confinement. Using soft confinement (porous polymer membranes), we reported the use of a novel solution impregnation method to form nanocrystals in polymer matrices with various microstructures to systemically study the role of soft confinement and polymer chemistry on the nucleation process of nano-sized crystals. We obtained 100% crystalline materials of four compounds in all experiments and in most cases nanocrystals were the most stable form. The smallest nanocrystals produced were ~ 100 nm. In the rigid confinement (porous silica particles of ~ 40nm pores), we explored the polymorphic outcome of four different compounds using solid state NMR. We found that three out of the four compounds can crystallize in the pores although one showed two polymorphs concomitantly crystallized the same time and another one produces a mixture of two polymorphs and amorphous states. All these nanocrystals under soft and rigid confinement showed significant enhancement of dissolution profiles. These results help advance the fundamental understanding of nucleation under rigid confinement and may lead to potential applications in developing new formulations in the pharmaceutical industry. The third approach is the use of nano spray drying. We used glycine as the model compound and compare this approach with the first one we developed, and the results suggest that the nanocrystals produced by spraying exhibit wider size distribution and worse surface structures. These defects existing on crystal surface may improve mobility of molecules and cause "crystal-bridging" to form big crystals. To explore the change in crystal solid properties regarding size, we also measured the solubility vs size curves of two polymorphs of glycine. Both polymorphs showed 20%-30% increase of solubility when crystal size goes down to -300 nm. Although the curves did not cross in the range that we measured, the extended trends suggested that p-glycine solubility could be lower than [beta]-glycine when the crystal size is smaller than ~100 nm.
by Xiaochuan Yang.
Ph. D.
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Parmar, Manish M. "Polymorph selection with morphology control using solvents and additives." Thesis, Liverpool John Moores University, 2016. http://researchonline.ljmu.ac.uk/4399/.

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Sulphathiazole is a highly polymorphic model system exhibiting at least five polymorphic forms: I, II, III, IV, and V. Polymorph stability is known to be susceptible to solvent environment, and it is established that 1-propanol stabilizes the most metastable form I. This study examines the effect of a range of alcohols on polymorph selection and attempts to elucidate the mechanism. The role of the alcohol functional group in the polymorph selection process is thus investigated and evaluated. Crystals were characterized using optical microscopy, SEM, PXRD, DSC, IR, and single-crystal X-ray diffraction for their polymorphic identity. The role of solvent in the stabilization of polymorphs was investigated by visualizing and calculating energy requirements for the interaction of each solvent molecule with α- and β-dimers of sulphathiazole, using Cerius2 modeling software and GRID based systematic search simulation. These studies showed that solvent had a significant impact on polymorph selection. In common with 1-propanol, 1-butanol was found to stabilize form I by inhibiting the formation of the β-dimer, which is necessary for nucleation of and transformation to forms II-IV. Shorter chain alcohols and branched chain alcohols such as methanol, 2-propanol, and ethanol did not stabilize form I but stabilized forms II, III, and IV, respectively, showing that it is not only the alcohol functionality but also the steric effects of the alkyl chain that contributed to the effect. Sulphathiazole form I normally has a needlelike morphology. Form I with a modified rodlike morphology was produced by crystallization from 1-propanol with the addition of methanol in low concentration, showing that it is possible to control the morphology and selectively isolate polymorphs. Indomethacin is known to exhibit at least five polymorphs but only the stable γ Form and metastable α Form are reported to be reliably produced by standard methods. The metastable α Form has an undesirable fibrous needle-like morphology. The current study focused on producing crystals of α Indomethacin with a well-defined morphology using additives. Adipic acid, myristic acid, oleic acid and structurally related 3-indoleacetic acid were selected as additives and their impact on the morphology and polymorphism of indomethacin were investigated in this study. Additives did not change the needle-like morphology of α-indomethacin but less fibrous and less aggregated well defined needles were observed in presence of adipic acid, oleic acid and 3-indole-3-acetic acid.
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Books on the topic "Polymorphic control"

1

Griffiths, Ronald W. The zebra mussel, Dreissena polymorpha (Pallas, 1771), in North America: Impact on raw water users. [S.l: s.n., 1989.

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V, Danks H., and International Congress of Entomology (19th : 1992 : Beijing, China), eds. Insect life-cycle polymorphism: Theory, evolution, and ecological consequences for seasonality and diapause control. Dordrecht, Netherlands: Kluwer Academic, 1994.

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Nakov, Svetlin. Fundamentals of Computer Programming with C#: The Bulgarian C# Book. Sofia, Bulgaria: Svetlin Nakov, 2013.

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Walkey, Allan J., and Jared Magnani. Therapeutic strategy in tachyarrhythmias. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199600830.003.0156.

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The therapeutic approach to tachyarrhythmias in the critically-ill patient involves rapid diagnosis and haemodynamic assessment. Patients who become haemodynamically unstable due to tachyarrhythmia warrant direct current cardioversion. Effects of direct current cardioversion during critical illness are often transient unless the underlying arrhythmia precipitant is eliminated and longer-acting rate- or rhythm-controlling medications are instituted. Atrial fibrillation often responds favourably to a rate-control strategy and treatment of the underlying precipitants. After initial clinical stabilization, clinical management involves elimination of potential arrhythmogenic triggers and administration of appropriate rate or rhythm control medications. Assessment of the QT interval in patients with polymorphic ventricular tachycardia is important in determining the underlying aetiology and treatment strategy. This chapter presents an evidence-based review of the therapeutic approach to tachyarrhythmias.
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Danks, H. V. Insect Life-Cycle Polymorphism: Theory, Evolution and Ecological Consequences for Seasonality and Diapause Control. Springer, 2013.

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Danks, H. V. Insect Life-cycle polymorphism: "Theory, Evolution and Ecological Consequences for Seasonality and Diapause Control". Springer, 2011.

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Danks, H. V. Insect Life-Cycle Polymorphism:: Theory, Evolution and Ecological Consequences for Seasonality and Diapause Control (Series Entomologica). Springer, 1994.

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L, Mackie Gerry, and Ontario Great Lakes Section, eds. The Zebra mussel, Dreissena polymorpha: A synthesis of European experiences and a preview for North America. Ottawa: Ontario Environment, 1990.

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L, Mackie Gerry, and B. A. R. Environmental, eds. The Zebra mussel, Dreissena polymorpha: A synthesis of European experiences and a preview for North America ; report prepared for Water Resources Branch, Great Lakes Section. [S.l.]: Queen's Printer for Ontario, 1990.

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Progress in Metabolic Syndrome Research. Nova Science Publishers, 2006.

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Book chapters on the topic "Polymorphic control"

1

Kokaji, Yuichiro, and Yukiyoshi Kameyama. "Polymorphic Multi-stage Language with Control Effects." In Programming Languages and Systems, 105–20. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-25318-8_11.

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Qiao, Chunming, Yousong Mei, Myungsik Yoo, and Xijun Zhang. "Polymorphic control for cost-effective design of optical networks." In Multichannel Optical Networks: Theory and Practice, 157–79. Providence, Rhode Island: American Mathematical Society, 1998. http://dx.doi.org/10.1090/dimacs/046/13.

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Laird, James. "A Curry-style Semantics of Interaction: From Untyped to Second-Order Lazy $$\lambda \mu $$-Calculus." In Lecture Notes in Computer Science, 422–41. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-45231-5_22.

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AbstractWe propose a “Curry-style” semantics of programs in which a nominal labelled transition system of types, characterizing observable behaviour, is overlaid on a nominal LTS of untyped computation. This leads to a notion of program equivalence as typed bisimulation.Our semantics reflects the role of types as hiding operators, firstly via an axiomatic characterization of “parallel composition with hiding” which yields a general technique for establishing congruence results for typed bisimulation, and secondly via an example which captures the hiding of implementations in abstract data types: a typed bisimulation for the (Curry-style) lazy $$\lambda \mu $$ λ μ -calculus with polymorphic types. This is built on an abstract machine for CPS evaluation of $$\lambda \mu $$ λ μ -terms: we first give a basic typing system for this LTS which characterizes acyclicity of the environment and local control flow, and then refine this to a polymorphic typing system which uses equational constraints on instantiated type variables, inferred from observable interaction, to capture behaviour at polymorphic and abstract types.
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Xiang, Min, Chang-jiang Jiang, Dong Yan, and Zhi-yong Luo. "A Dynamic Topology Control Algorithm Based on Polymorphic Ant Colony in Wireless Sensor Networks." In Information and Business Intelligence, 109–15. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-29084-8_17.

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Danks, H. V. "Diversity and integration of life-cycle controls in insects." In Insect life-cycle polymorphism, 5–40. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-017-1888-2_2.

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Wipking, Wolfgang, and Claudia Mengelkoch. "Control of alternate-year flight activities in high-alpine Ringlet butterflies (Erebia, Satyridae) and Burnet moths (Zygaena, Zygaenidae) from temperate environments." In Insect life-cycle polymorphism, 313–47. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-017-1888-2_15.

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Delhaes, P. "Polymorphism in Carbons and Parent Materials." In Design and Control of Structure of Advanced Carbon Materials for Enhanced Performance, 3–27. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-010-1013-9_1.

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Black, Samuel J. "Control of pathogenesis in African animal trypanosomiasis: a search for answers at ILRAD, ILCA and ILRI, 1975-2018." In The impact of the International Livestock Research Institute, 103–47. Wallingford: CABI, 2020. http://dx.doi.org/10.1079/9781789241853.0103.

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Abstract This book chapter describes the management of animal trypanosomiasis: (i) vector control/eradication; (ii) use of trypanocides; and (iii) use of trypanotolerant breeds of cattle. Vector control includes reducing the tsetse fly population with traps and insecticides, and in areas with a high population of trypanosome infected tsetse, animals are prophylactically administered antiparasitic drugs. To date, there is no AAT vaccine available, as discussed below. While disappointing with respect to AAT control, studies of AAT pathogenesis at ILRAD/ILRI did identify the definitive question for immunological research on AAT, namely, how do trypanosomes eliminate TD antibody responses in trypanosomiasis-susceptible mammals? In addition, the work at ILRI on the genetic basis of trypanotolerance contributed a high-density singlenucleotide polymorphism (SNP) map of the bovine genome that has intrinsic value for analysis of QTLs that control other traits, including susceptibility to other diseases.
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Brachthäuser, Jonathan Immanuel. "What You See Is What You Get: Practical Effect Handlers in Capability-Passing Style." In Ernst Denert Award for Software Engineering 2020, 15–43. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-83128-8_3.

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AbstractStructuring control flow is an essential task almost every programmer faces on a daily basis. At the same time, the control flow of software applications is becoming increasingly complicated, motivating languages to include more and more features like asynchronous programming and generators. Effect handlers are a promising alternative since they can express many of these features as libraries. To bring effect handlers closer to the software engineering practice, we present capability passing as an implementation technique for effect handlers. Capability passing provides the basis for the integration of effect handlers into mainstream object-oriented programming languages and thereby unlocks novel modularization strategies. It also enables programmers to apply lexical reasoning about effects and gives rise to a new form of effect polymorphism. Finally, it paves the path for efficient compilation strategies of control effects.
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Hardie, Jim. "A hormonal Basis for the Photoperiodic Control of Polymorphism in Aphids." In Ciba Foundation Symposium 104 - Photoperiodic Regulation of Insect and Molluscan Hormones, 240–58. Chichester, UK: John Wiley & Sons, Ltd., 2008. http://dx.doi.org/10.1002/9780470720851.ch15.

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Conference papers on the topic "Polymorphic control"

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Hermanto, Martin Wijaya, Richard D. Braatz, and Min-Sen Chiu. "Optimal Control of Polymorphic Transformation in Batch Pharmaceutical Crystallization." In 2007 IEEE International Conference on Control Applications. IEEE, 2007. http://dx.doi.org/10.1109/cca.2007.4389221.

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Ippolito, Corey, and Khalid Al-Ali. "Topological Constructs for Automatic Reconfiguration of Polymorphic Control Systems." In AIAA Infotech@Aerospace 2007 Conference and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2007. http://dx.doi.org/10.2514/6.2007-2832.

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Hermanto, Martin Wijaya, Richard D. Braatz, and Min-Sen Chiu. "Optimal Control of Polymorphic Transformation in Batch Pharmaceutical Crystallization." In 2007 IEEE 22nd International Symposium on Intelligent Control. IEEE, 2007. http://dx.doi.org/10.1109/isic.2007.4359795.

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Ippolito, Corey, Sungmoon Joo, Khalid Al-Ali, and Yoo Hsiu Yeh. "Polymorphic Control Reconfiguration in an Autonomous UAV with UGV Collaboration." In 2008 IEEE Aerospace Conference. IEEE, 2008. http://dx.doi.org/10.1109/aero.2008.4526291.

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Hermanto, Martin Wijaya, Richard D. Braatz, and Min-Sen Chiu. "A run-to-run control strategy for polymorphic transformation in pharmaceutical crystallization." In 2006 IEEE Conference on Computer Aided Control System Design, 2006 IEEE International Conference on Control Applications, 2006 IEEE International Symposium on Intelligent Control. IEEE, 2006. http://dx.doi.org/10.1109/cacsd-cca-isic.2006.4776968.

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Ippolito, Corey, Khalid Al-Ali, and John Dolan. "Polymorphic Control of an Autonomous Ground Vehicle over Wireless Mobile Networks." In AIAA Infotech@Aerospace 2010. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2010. http://dx.doi.org/10.2514/6.2010-3346.

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Hermanto, Martin, Richard Braatz, and Min-sen Chiu. "A Run-to-run Control Strategy for Polymorphic Transformation in Pharmaceutical Crystallization." In 2006 IEEE International Conference on Control Applications. IEEE, 2006. http://dx.doi.org/10.1109/cca.2006.286194.

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Brady, John J., Brittney L. Argirakis, Alexander D. Gordon, Richard T. Lareau, and Barry T. Smith. "A method to control the polymorphic phase for RDX-based trace standards." In SPIE Defense + Security, edited by Augustus W. Fountain. SPIE, 2016. http://dx.doi.org/10.1117/12.2223837.

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Lu, Yuzhou, Qihe Shan, Pu Zhang, and Tieshan Li. "Topology Design for Multiple Unmanned Surface Vessels Cooperative Control in Polymorphic Networks." In 2022 4th International Conference on Data-driven Optimization of Complex Systems (DOCS). IEEE, 2022. http://dx.doi.org/10.1109/docs55193.2022.9967745.

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Li, Jinglun, Xin Gu, Yue Wang, Ziheng Mao, Kailong Liu, and Yunlong Shang. "A Hierarchical Fault Diagnosis Method for Lithium Battery Based on Polymorphic Jump." In 2022 6th CAA International Conference on Vehicular Control and Intelligence (CVCI). IEEE, 2022. http://dx.doi.org/10.1109/cvci56766.2022.9964664.

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Reports on the topic "Polymorphic control"

1

Aziz, Md Abdul, Tahmina Akter, and Mohammad Safiqul Islam. Effect of miR-196a2 rs11614913 polymorphism on cancer susceptibility: evidence from an updated meta-analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, May 2022. http://dx.doi.org/10.37766/inplasy2022.5.0027.

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Review question / Objective: MiR-196a2 rs11614913 polymorphism has been studied in a wide range of cancers throughout the years. Despite a large number of epidemiological studies performed in almost all ethnic populations, the contribution of this polymorphism in cancer risk is still inconclusive. Therefore, this updated meta-analysis was performed to estimate a meticulous correlation between miR-196a2 rs11614913 variant and cancer susceptibility. Condition being studied: Different types of cancer patients and healthy controls were evaluated to detect the cancer risk in the individual case-control studies. We performed a meta analysis of these case control studies to get a pulled outcome risk.
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Abbott, Albert G., Doron Holland, Douglas Bielenberg, and Gregory Reighard. Structural and Functional Genomic Approaches for Marking and Identifying Genes that Control Chilling Requirement in Apricot and Peach Trees. United States Department of Agriculture, September 2009. http://dx.doi.org/10.32747/2009.7591742.bard.

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Structural and functional genomic approaches for marking and identifying genes that control chilling requirement in apricot and peach trees. Specific aims: 1) Identify and characterize the genetic nature of chilling requirement for flowering and dormancy break of vegetative shoots in Prunusgermplasm through the utilization of existing apricot (NeweYa'ar Research Center, ARO) and peach (Clemson University) genetic mapping populations; 2) Use molecular genetic mapping techniques to identify markers flanking genomic regions controlling chilling; 3) Comparatively map the regions controlling chilling requirement in apricot and peach and locate important genomic regions influencing chilling requirement on the Prunus functional genomic database as an initial step for identification of candidate genes; 4) Develop from the functional genomics database a set of markers facilitating the development of cultivars with optimized chilling requirements for improved and sustained fruit production in warm-winter environments. Dormant apricot (prunus armeniaca L.) and peach [Prunus persica (L.) Batsch] trees require sustained exposure to low, near freezing, temperatures before vigorous floral and vegetative bud break is possible after the resumption of warm temperatures in the spring. The duration of chilling required (the chilling requirement, CR) is determined by the climatic adaptation of the particular cultivar, thus limiting its geographic distribution. This limitation is particularly evident when attempting to introduce superior cultivars to regions with very warm winter temperatures, such as Israel and the coastal southern United States. The physiological mechanism of CR is not understood and although breeding programs deliberately manipulate CR in apricot and peach crosses, robust closely associated markers to the trait are currently not available. We used segregating populations of apricot (100 Fl individuals, NeweYa'ar Research Center, ARO) and peach (378 F2 individuals, Clemson University) to discover several discreet genomic loci that regulate CR and blooming date. We used the extensive genomic/genetic resources available for Prunus to successfully combine our apricot and peach genetic data and identify five QTL with strong effects that are conserved between species as well as several QTL that are unique to each species. We have identified markers in the key major QTL regions for testing in breeding programs which we are carrying out currently; we have identified an initial set of candidate genes using the peach physical/transcriptome map and whole peach genome sequences and we are testing these currently to identify key target genes for manipulation in breeding programs. Our collaborative work to date has demonstrated the following: 1) CR in peach and apricot is predominantly controlled by a limited number ofQTL loci, seven detected in a peach F2 derived map comprising 65% of the character and 12 in an apricot Fl map comprising 71.6% and 55.6% of the trait in the Perfection and A. 1740 parental maps, respectively and that peach and apricot appear in our initial maps to share five genomic intervals containing potentially common QTL. 2) Application of common anchor markers of the Prunus/peach, physical/genetic map resources has allowed us not only to identify the shared intervals but also to have immediately available some putative candidate gene information from these intervals, the EVG region on LG1 in peach the TALY 1 region in apricot on LG2 in peach; and several others involved in vernalization pathways (LGI and LG7). 3) Mapped BACcontigs are easily defined from the complete physical map resources in peach through the common SSR markers that anchor our CR maps in the two species, 4) Sequences of BACs in these regions can be easily mined for additional polymorphic markers to use in MAS applications.
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Jafrin, Sarah, Md Abdul Aziz, and Mohammad Safiqul Islam. Insight into the Role of IL-1β rs1143634 (+3954C>T) Polymorphism in Cancer Risk: An Updated Meta-analysis and Trial Sequential Analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, October 2021. http://dx.doi.org/10.37766/inplasy2021.10.0044.

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Review question / Objective: To assess the link of IL-1β rs1143634 (+3954C>T) Polymorphism with cancer. Condition being studied: The included studies must contain 1) genotypic information and detailed data of IL-1β rs1143634 (+3954C>T) polymorphism 2) case-control studies. Information sources: PubMed, Google Scholar, CNKI, Web of Science, and EMBASE.
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Levisohn, Sharon, Maricarmen Garcia, David Yogev, and Stanley Kleven. Targeted Molecular Typing of Pathogenic Avian Mycoplasmas. United States Department of Agriculture, January 2006. http://dx.doi.org/10.32747/2006.7695853.bard.

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Intraspecies identification (DNA "fingerprinting") of pathogenic avian mycoplasmas is a powerful tool for epidemiological studies and monitoring strain identity. However the only widely method available for Mycoplasma gallisepticum (MG) and M. synoviae (MS)wasrandom amplified polymorphic DNA (RAPD). This project aimed to develop alternative and supplementary typing methods that will overcome the major constraints of RAPD, such as the need for isolation of the organism in pure culture and the lack of reproducibility intrinsic in the method. Our strategy focussed on recognition of molecular markers enabling identification of MG and MS vaccine strains and, by extension, pathogenic potential of field isolates. Our first aim was to develop PCR-based systems which will allow amplification of specific targeted genes directly from clinical material. For this purpose we evaluated the degree of intraspecies heterogeneity in genes encoding variable surface antigens uniquely found in MG all of which are putative pathogenicity factors. Phylogenic analysis of targeted sequences of selected genes (pvpA, gapA, mgc2, and lp) was employed to determine the relationship among MG strains.. This method, designated gene targeted sequencing (GTS), was successfully employed to identify strains and to establish epidemiologically-linked strain clusters. Diagnostic PCR tests were designed and validated for each of the target genes, allowing amplification of specific nucleotide sequences from clinical samples. An mgc2-PCR-RFLP test was designed for rapid differential diagnosis of MG vaccine strains in Israel. Addressing other project goals, we used transposon mutagenesis and in vivo and in vitro models for pathogenicity to correlated specific changes in target genes with biological properties that may impact the course of infection. An innovative method for specific detection and typing of MS strains was based on the hemagglutinin-encoding gene vlhA, uniquely found in this species. In parallel, we evaluated the application of amplified fragment length polymorphism (AFLP) in avian mycoplasmas. AFLP is a highly discriminatory method that scans the entire genome using infrequent restriction site PCR. As a first step the method was found to be highly correlated with other DNA typing methods for MG species and strain differentiation. The method is highly reproducible and relatively rapid, although it is necessary to isolate the strain to be tested. Both AFLP and GTS are readily to amenable to computer-assisted analysis of similarity and construction of a data-base resource. The availability of improved and diverse tools will help realize the full potential of molecular typing of avian mycoplasmas as an integral and essential part of mycoplasma control programs.
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Aziz, Md Abdul, Sarah Jafrin, Md Abdul Barek, Shamima Nasrin Anonna, and Mohammad Safiqul Islam. The Association between Matrix Metalloproteinase-3 -1171 (5A/6A) Promoter Polymorphism and Cancer Susceptibility: An Updated Meta-Analysis and Trial Sequential Analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, August 2022. http://dx.doi.org/10.37766/inplasy2022.8.0049.

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Review question / Objective: The polymorphism of the 5A/6A promoter region of matrix metalloproteinases-3-1171 has been comprehensively studied to evaluate its risk associated with various cancers. We performed this updated meta-analysis to clarify the inconclusive outcomes of previous studies and to verify the link of this specific variant with the cancer risk. Eligibility criteria: For the literature covered in this meta-analysis, the authors followed some standards as inclusion criteria: (a) comparative case-control or cohort (different case groups) studies stating the correlation of MMP-3 -1171 (5A/6A) variant with cancer risk; (b) Available genotype and allele data in cases and controls; (c) Sufficient data to determine ORs (odds ratios) with 95% Cis (confidence intervals). The substandard studies were: (a) Review articles, commentaries and duplicate studies; (b) Study graph apart from case-control comparative approaches; (c) Studies having inadequate genotypic information to compute ORs with 95% CIs.
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Zou, Chenghui, Weng Zhang, Mao Li, Dan He, Yujie Han, and Mao Lu. A meta-analysis of association between CCL5、CCL11、CCL17 polymorphisms and AD. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, November 2022. http://dx.doi.org/10.37766/inplasy2022.11.0148.

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Review question / Objective: At present, many studies on the association between CCL5、CCL11、CCL17 polymorphisms and atopic dermatitis（AD）are inconsistent. We conducted this meta-analysis of Case control trial to evaluate the association between CCL5、CCL11、CCL17 polymorphisms and atopic dermatitis（AD). Condition being studied: Since the discovery of cytokines, and in particular the role of chemokines in the progression of AD, many clinical studies have been carried out around the world to explore the association of AD with chemokine polymorphism. However, the quality, type and conclusions of studies on the correlation between chemokine polymorphism and AD are inconsistent. Foreign studies have shown that chemokine polymorphism is statistically significant in relation to AD. Studies by Menzies-Gow A et al have shown that a new therapeutic strategy targeting to block CCL11 signal has been proven to significantly improve patients with moderate to severe AD. However, some foreign studies have also reported that chemokine polymorphism is unrelated to AD.
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Breiman, Adina, Jan Dvorak, Abraham Korol, and Eduard Akhunov. Population Genomics and Association Mapping of Disease Resistance Genes in Israeli Populations of Wild Relatives of Wheat, Triticum dicoccoides and Aegilops speltoides. United States Department of Agriculture, December 2011. http://dx.doi.org/10.32747/2011.7697121.bard.

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Wheat is the most widely grown crop on earth, together with rice it is second to maize in total global tonnage. One of the emerging threats to wheat is stripe (yellow) rust, especially in North Africa, West and Central Asia and North America. The most efficient way to control plant diseases is to introduce disease resistant genes. However, the pathogens can overcome rapidly the effectiveness of these genes when they are wildly used. Therefore, there is a constant need to find new resistance genes to replace the non-effective genes. The resistance gene pool in the cultivated wheat is depleted and there is a need to find new genes in the wild relative of wheat. Wild emmer (Triticum dicoccoides) the progenitor of the cultivated wheat can serve as valuable gene pool for breeding for disease resistance. Transferring of novel genes into elite cultivars is highly facilitated by the availability of information of their chromosomal location. Therefore, our goals in this study was to find stripe rust resistant and susceptible genotypes in Israeli T. dicoccoides population, genotype them using state of the art genotyping methods and to find association between genetic markers and stripe rust resistance. We have screened 129 accessions from our collection of wild emmer wheat for resistance to three isolates of stripe rust. About 30% of the accessions were resistant to one or more isolates, 50% susceptible, and the rest displayed intermediate response. The accessions were genotyped with Illumina'sInfinium assay which consists of 9K single nucleotide polymorphism (SNP) markers. About 13% (1179) of the SNPs were polymorphic in the wild emmer population. Cluster analysis based on SNP diversity has shown that there are two main groups in the wild population. A big cluster probably belongs to the Horanum ssp. and a small cluster of the Judaicum ssp. In order to avoid population structure bias, the Judaicum spp. was removed from the association analysis. In the remaining group of genotypes, linkage disequilibrium (LD) measured along the chromosomes decayed rapidly within one centimorgan. This is the first time when such analysis is conducted on a genome wide level in wild emmer. Such a rapid decay in LD level, quite unexpected for a selfer, was not observed in cultivated wheat collection. It indicates that wild emmer populations are highly suitable for association studies yielding a better resolution than association studies in cultivated wheat or genetic mapping in bi-parental populations. Significant association was found between an SNP marker located in the distal region of chromosome arm 1BL and resistance to one of the isolates. This region is not known in the literature to bear a stripe rust resistance gene. Therefore, there may be a new stripe rust resistance gene in this locus. With the current fast increase of wheat genome sequence data, genome wide association analysis becomes a feasible task and efficient strategy for searching novel genes in wild emmer wheat. In this study, we have shown that the wild emmer gene pool is a valuable source for new stripe rust resistance genes that can protect the cultivated wheat.
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8

McElwain, Terry, Eugene Pipano, Guy Palmer, Varda Shkap, Stephen Hines, and Douglas Jasmer. Protection of Cattle Against Babesiosis: Immunization with Recombinant DNA Derived Apical Complex Antigens of Babesia bovis. United States Department of Agriculture, June 1995. http://dx.doi.org/10.32747/1995.7612835.bard.

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Bovine babesiosis caused by Babesia bovis continues to be a significant deterrent to global livestock production. Current control methods have both biological and technical drawbacks that have stimulated research on improved methods of vaccination. This BARD project has focused on characterization of candidate Babesia bovis vaccine antigens located in the apical complex, a unique group of subcellular organelles - including rhoptries, micronemes, and spherical bodies - involved in the invation of erythrocytes. Spherical bodies and rhoptries were partially purified and their contents characterized using monoclonal antibodies. Existing and newly developed monoclonal antibodies bound to antigens in the spherical body, rhoptry, merozoite membrane, and infected erythrocyte membrane. In an initial immunization study using biologically cloned strains, it was demonstrated that strain-common epitopes are important for inducing immune protection against heterologous challenge. Rhoptry-associated antigen 1 (RAP-1) had been demonstrated previously to induce partial immune protection, fulfilled criteria of broad interstrain B and T cell epitope conservation, and thus was further characterized. The RAP-1 gene family consists of at least two gene copies, is homologous to the RAP-1 gene family in B. bigemina, and contains significant sequence similarity to other erythroparasitic protozoan candidate vaccine antigens, including the apical membrane antigen of Plasmodium falciparum. A new RAP-1 monoclonal antibody was developed that inhibits merozoite growth in vitro, demonstrating the presence of a RAP-1 neutralization sensitive domain. Based on these observations, cattle were immunized with Mo7 (Mexico) strain recombinant RAP-1 representing one of the two gene copies. All cattle responded with variable levels of serum antibodies inhibitory to heterologous Israel strain merozoite growth in vitro, and RAP-1 specific T lymphocytes that proliferated when stimulated with either homologous or heterologous native parasite antigen. Minimal protection from clinical disease was present after virulent Israel (heterologous) strain B. bovis challenge. In total, the results support the continued development of RAP-1 as a vaccine antigen, but indicate that additional information about the native structure and function of both RAP-1 gene copies, including the relationship of conserved and polymorphic sequences to B and T cell lepitopes relevant for protection, is necessary for optimization of RAP-1 as a vaccine component.
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Jafrin, Sarah, Md Abdul Aziz, and Mohammad Safiqul Islam. Extended Investigation on the connection of TP73 G4C14-A4T14 Polymorphism with different Cancer Types – An Updated Meta-analysis with 56 Case-control Studies. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, January 2022. http://dx.doi.org/10.37766/inplasy2022.1.0070.

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Review question / Objective: TP73 G4C14-A4T14 variant has been suspected of elevating the risk of cancer for many years. The available evidence was unsatisfactory and could not provide a reliable conclusion. Therefore, we performed this meta-analysis to re-evaluate the previous findings and illustrate the actual role of TP73 G4C14-A4T14 variant on cancer development. Condition being studied: The association of the G4C14-A4T14 variant with cancer risk was studied. Information sources: PubMed, Google Scholar, EMBASE, Cochrane Library, and Web of Science, CNKI.
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10

Michelmore, Richard, Eviatar Nevo, Abraham Korol, and Tzion Fahima. Genetic Diversity at Resistance Gene Clusters in Wild Populations of Lactuca. United States Department of Agriculture, February 2000. http://dx.doi.org/10.32747/2000.7573075.bard.

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Genetic resistance is often the least expensive, most effective, and ecologically-sound method of disease control. It is becoming apparent that plant genomes contain large numbers of disease resistance genes. However, the numbers of different resistance specificities within a genepool and the genetic mechanisms generating diversity are poorly understood. Our objectives were to characterize diversity in clusters of resistance genes in wild progenitors of cultivated lettuce in Israel and California in comparison to diversity within cultivated lettuce, and to determine the extent of gene flow, recombination, and genetic instability in generating variation within clusters of resistance genes. Genetic diversity of resistance genes was analyzed in wild and cultivated germplasm using molecular markers derived from lettuce resistance gene sequences of the NBS-LRR type that mapped to the major cluster if resistance genes in lettuce (Sicard et al. 1999). Three molecular markers, one microsatellite marker and two SCAR markers that amplified LRR- encoding regions, were developed from sequences of resistance gene homologs at the Dm3 cluster (RGC2s) in lettuce. Variation for these markers was assessed in germplasm including 74 genotypes of cultivated lettuce, L. saliva and 71 accessions of the three wild Lactuca spp., L. serriola, L. saligna and L. virosa that represent the major species in the sexually accessible genepool for lettuce. Diversity was also studied within and between natural populations of L. serriola from Israel and California. Large numbers of haplotypes were detected indicating the presence of numerous resistance genes in wild species. We documented a variety of genetic events occurring at clusters of resistance genes for the second objective (Sicard et al., 1999; Woo el al., in prep; Kuang et al., in prepb). The diversity of resistance genes in haplotypes provided evidence for gene duplication and unequal crossing over during the evolution of this cluster of resistance genes. Comparison of nine resistance genes in cv. Diana identified 22 gene conversion and five intergenic recombinations. We cloned and sequenced a 700 bp region from the middle of RGC2 genes from six genotypes, two each from L. saliva, L. serriola, and L. saligna . We have identified over 60 unique RGC2 sequences. Phylogenetic analysis surprisingly demonstrated much greater similarity between than within genotypes. This led to the realization that resistance genes are evolving much slower than had previously been assumed and to a new model as to how resistance genes are evolving (Michelmore and Meyers, 1998). The genetic structure of L. serriola was studied using 319 AFLP markers (Kuang et al., in prepa). Forty-one populations from Turkey, Armenia, Israel, and California as well as seven European countries were examined. AFLP marker data showed that the Turkish and Armenian populations were the most polymorphic populations and the European populations were the least. The Davis, CA population, a recent post-Columbian colonization, showed medium genetic diversity and was genetically close to the Turkish populations. Our results suggest that Turkey - Armenia may be the center of origin and diversity of L. serriola and may therefore have the greatest diversity of resistance genes. Our characterization of the diversity of resistance genes and the genetic mechanisms generating it will allow informed exploration, in situ and ex situ conservation, and utilization of germplasm resources for disease control. The results of this project provide the basis for our future research work, which will lead to a detailed understanding of the evolution of resistance genes in plants.
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