Relevant bibliographies by topics / PBpa

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Academic literature on the topic 'PBpa'

Author: Grafiati
Published: 4 June 2021
Last updated: 13 February 2022

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Journal articles on the topic "PBpa"

1

Wei, Yuping, Teresa Havasy, Derrell C. McPherson, and David L. Popham. "Rod Shape Determination by the Bacillus subtilis Class B Penicillin-Binding Proteins Encoded by pbpA and pbpH." Journal of Bacteriology 185, no. 16 (2003): 4717–26. http://dx.doi.org/10.1128/jb.185.16.4717-4726.2003.

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ABSTRACT The peptidoglycan cell wall determines the shape and structural integrity of a bacterial cell. Class B penicillin-binding proteins (PBPs) carry a transpeptidase activity that cross-links peptidoglycan strands via their peptide side chains, and some of these proteins are directly involved in cell shape determination. No Bacillus subtilis PBP with a clear role in rod shape maintenance has been identified. However, previous studies showed that during outgrowth of pbpA mutant spores, the cells grew in an ovoid shape for several hours before they recovered and took on a normal rod shape. It was postulated that another PBP, expressed later during outgrowth, was able to compensate for the lack of the pbpA product, PBP2a, and to guide the formation of a rod shape. The B. subtilis pbpH (ykuA) gene product is predicted to be a class B PBP with greatest sequence similarity to PBP2a. We found that a pbpH-lacZ fusion was expressed at very low levels in early log phase and increased in late log phase. A pbpH null mutant was indistinguishable from the wild-type, but a pbpA pbpH double mutant was nonviable. When pbpH was placed under the control of an inducible promoter in a pbpA mutant, viability was dependent on pbpH expression. Growth of this strain in the absence of inducer resulted in conversion of the cells from rods to ovoid/round shapes and lysis. We conclude that PBP2a and PbpH play redundant roles in formation of a rod-shaped peptidoglycan cell wall.
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2

Pereira, S. F. F., A. O. Henriques, M. G. Pinho, H. de Lencastre, and A. Tomasz. "Role of PBP1 in Cell Division of Staphylococcus aureus." Journal of Bacteriology 189, no. 9 (2007): 3525–31. http://dx.doi.org/10.1128/jb.00044-07.

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ABSTRACT We constructed a conditional mutant of pbpA in which transcription of the gene was placed under the control of an IPTG (isopropyl-β-d-thiogalactopyranoside)-inducible promoter in order to explore the role of PBP1 in growth, cell wall structure, and cell division. A methicillin-resistant strain and an isogenic methicillin-susceptible strain, each carrying the pbpA mutation, were unable to grow in the absence of the inducer. Conditional mutants of pbpA transferred into IPTG-free medium underwent a four- to fivefold increase in cell mass, which was not accompanied by a proportional increase in viable titer. Examination of thin sections of such cells by transmission electron microscopy or fluorescence microscopy of intact cells with Nile red-stained membranes showed a morphologically heterogeneous population of bacteria with abnormally increased sizes, distorted axial ratios, and a deficit in the number of cells with completed septa. Immunofluorescence with an antibody specific for PBP1 localized the protein to sites of cell division. No alteration in the composition of peptidoglycan was detectable in pbpA conditional mutants grown in the presence of a suboptimal concentration of IPTG, which severely restricted the rate of growth, and the essential function of PBP1 could not be replaced by PBP2A present in methicillin-resistant cells. These observations suggest that PBP1 is not a major contributor to the cross-linking of peptidoglycan and that its essential function must be intimately integrated into the mechanism of cell division.
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3

Murray, Thomas, David L. Popham, Christine B. Pearson, Arthur R. Hand, and Peter Setlow. "Analysis of Outgrowth of Bacillus subtilis Spores Lacking Penicillin-Binding Protein 2a." Journal of Bacteriology 180, no. 24 (1998): 6493–502. http://dx.doi.org/10.1128/jb.180.24.6493-6502.1998.

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ABSTRACT The loss of Bacillus subtilis penicillin-binding protein (PBP) 2a, encoded by pbpA, was previously shown to slow spore outgrowth and result in an increased diameter of the outgrowing spore. Further analyses to define the defect inpbpA spore outgrowth have shown that (i) outgrowingpbpA spores exhibited only a slight defect in the rate of peptidoglycan (PG) synthesis compared to wild-type spores, but PG turnover was significantly slowed during outgrowth of pbpAspores; (ii) there was no difference in the location of PG synthesis in outgrowing wild-type and pbpA spores once cell elongation had been initiated; (iii) outgrowth and elongation of pbpAspores were dramatically affected by the levels of monovalent or divalent cations in the medium; (iv) there was a partial redundancy of function between PBP2a and PBP1 or -4 during spore outgrowth; and (v) there was no difference in the structure of PG from outgrowing wild-type spores or spores lacking PBP2a or PBP2a and -4; but also (vi) PG from outgrowing spores lacking PBP1 and -2a had transiently decreased cross-linking compared to PG from outgrowing wild-type spores, possibly due to the loss of transpeptidase activity.
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4

Wada, Akihito, and Haruo Watanabe. "Penicillin-Binding Protein 1 ofStaphylococcus aureus Is Essential for Growth." Journal of Bacteriology 180, no. 10 (1998): 2759–65. http://dx.doi.org/10.1128/jb.180.10.2759-2765.1998.

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ABSTRACT pbpA, a gene encoding penicillin-binding protein (PBP) 1 of Staphylococcus aureus, was cloned in anEscherichia coli MC1061 transformant which grew on a plate containing 512 μg of vancomycin per ml. This gene encodes a 744-amino-acid sequence which conserves three motifs of PBPs, SXXK, SXN, and KTG. The chromosomal copy of pbpA could be disrupted only when RN4220, a methicillin-sensitive S. aureus strain, had additional copies of pbpA in its episome. Furthermore, these episomal copies of pbpA could not be eliminated by an incompatible plasmid when the chromosomal copy of pbpA was disrupted beforehand. Based on these observations, we concluded that pbpA is essential for the growth of methicillin-sensitive S. aureus.
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5

Ropy, Alaa, Gabriel Cabot, Irina Sánchez-Diener та ін. "Role of Pseudomonas aeruginosa Low-Molecular-Mass Penicillin-Binding Proteins in AmpC Expression, β-Lactam Resistance, and Peptidoglycan Structure". Antimicrobial Agents and Chemotherapy 59, № 7 (2015): 3925–34. http://dx.doi.org/10.1128/aac.05150-14.

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ABSTRACTThis study aimed to characterize the role ofPseudomonas aeruginosalow-molecular-mass penicillin-binding proteins (LMM PBPs), namely, PBP4 (DacB), PBP5 (DacC), and PBP7 (PbpG), in peptidoglycan composition, β-lactam resistance, andampCregulation. For this purpose, we constructed all single and multiple mutants ofdacB,dacC,pbpG, andampCfrom the wild-typeP. aeruginosaPAO1 strain. Peptidoglycan composition was determined by high-performance liquid chromatography (HPLC),ampCexpression by reverse transcription-PCR (RT-PCR), PBP patterns by a Bocillin FL-binding test, and antimicrobial susceptibility by MIC testing for a panel of β-lactams. Microscopy and growth rate analyses revealed no apparent major morphological changes for any of the mutants compared to the wild-type PAO1 strain. Of the single mutants, onlydacCmutation led to significantly increased pentapeptide levels, showing that PBP5 is the majordd-carboxypeptidase inP. aeruginosa. Moreover, our results indicate that PBP4 and PBP7 play a significant role asdd-carboxypeptidase only if PBP5 is absent, and theirdd-endopeptidase activity is also inferred. As expected, the inactivation of PBP4 led to a significant increase inampCexpression (around 50-fold), but, remarkably, the sequential inactivation of the three LMM PBPs produced a much greater increase (1,000-fold), which correlated with peptidoglycan pentapeptide levels. Finally, the β-lactam susceptibility profiles of the LMM PBP mutants correlated well with theampCexpression data. However, the inactivation ofampCin these mutants also evidenced a role of LMM PBPs, especially PBP5, in intrinsic β-lactam resistance. In summary, in addition to assessing the effect ofP. aeruginosaLMM PBPs on peptidoglycan structure for the first time, we obtained results that represent a step forward in understanding the impact of these PBPs on β-lactam resistance, apparently driven by the interplay between their roles in AmpC induction, β-lactam trapping, anddd-carboxypeptidase/β-lactamase activity.
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6

Dasgupta, Arunava, Pratik Datta, Manikuntala Kundu, and Joyoti Basu. "The serine/threonine kinase PknB of Mycobacterium tuberculosis phosphorylates PBPA, a penicillin-binding protein required for cell division." Microbiology 152, no. 2 (2006): 493–504. http://dx.doi.org/10.1099/mic.0.28630-0.

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A cluster of genes encoded by ORFs Rv0014c–Rv0018c in Mycobacterium tuberculosis encodes candidate cell division proteins RodA and PBPA, a pair of serine/threonine kinases (STPKs), PknA and PknB, and a phosphatase, PstP. The organization of genes encompassing this region is conserved in a large number of mycobacterial species. This study demonstrates that recombinant PBPA of M. tuberculosis binds benzylpenicillin. Knockout of its counterpart in M. smegmatis resulted in hindered growth and defective cell septation. The phenotype of the knockout (PBPA-KO) could be restored to that of the wild-type upon expression of PBPA of M. tuberculosis. PBPA localized to the division site along with newly synthesized peptidoglycan, between segregated nucleoids. In vivo coexpression of PBPA and PknB, in vitro kinase assays and site-specific mutagenesis substantiated the view that PknB phosphorylates PBPA on T362 and T437. A T437A mutant could not complement PBPA-KO. These studies demonstrate for the first time that PBPA, which belongs to a subclass of class B high-molecular-mass PBPs, plays an important role in cell division and cell shape maintenance. Signal transduction mediated by PknB and PstP likely regulates the positioning of this PBP at the septum, thereby regulating septal peptidoglycan biosynthesis.
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Philippe, Nadège, Ludovic Pelosi, Richard E. Lenski, and Dominique Schneider. "Evolution of Penicillin-Binding Protein 2 Concentration and Cell Shape during a Long-Term Experiment with Escherichia coli." Journal of Bacteriology 191, no. 3 (2008): 909–21. http://dx.doi.org/10.1128/jb.01419-08.

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ABSTRACT Peptidoglycan is the major component of the bacterial cell wall and is involved in osmotic protection and in determining cell shape. Cell shape potentially influences many processes, including nutrient uptake as well as cell survival and growth. Peptidoglycan is a dynamic structure that changes during the growth cycle. Penicillin-binding proteins (PBPs) catalyze the final stages of peptidoglycan synthesis. Although PBPs are biochemically and physiologically well characterized, their broader effects, especially their effects on organismal fitness, are not well understood. In a long-term experiment, 12 populations of Escherichia coli having a common ancestor were allowed to evolve for more than 40,000 generations in a defined environment. We previously identified mutations in the pbpA operon in one-half of these populations; this operon encodes PBP2 and RodA proteins that are involved in cell wall elongation. In this study, we characterized the effects of two of these mutations on competitive fitness and other phenotypes. By constructing and performing competition experiments with strains that are isogenic except for the pbpA alleles, we showed that both mutations that evolved were beneficial in the environment used for the long-term experiment and that these mutations caused parallel phenotypic changes. In particular, they reduced the cellular concentration of PBP2, thereby generating spherical cells with an increased volume. In contrast to their fitness-enhancing effect in the environment where they evolved, both mutations decreased cellular resistance to osmotic stress. Moreover, one mutation reduced fitness during prolonged stationary phase. Therefore, alteration of the PBP2 concentration contributed to physiological trade-offs and ecological specialization during experimental evolution.
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Cayô, Rodrigo, María-Cruz Rodríguez, Paula Espinal, et al. "Analysis of Genes Encoding Penicillin-Binding Proteins in Clinical Isolates of Acinetobacter baumannii." Antimicrobial Agents and Chemotherapy 55, no. 12 (2011): 5907–13. http://dx.doi.org/10.1128/aac.00459-11.

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ABSTRACTThere is limited information on the role of penicillin-binding proteins (PBPs) in the resistance ofAcinetobacter baumanniito β-lactams. This study presents an analysis of the allelic variations of PBP genes inA. baumanniiisolates. Twenty-sixA. baumanniiclinical isolates (susceptible or resistant to carbapenems) from three teaching hospitals in Spain were included. The antimicrobial susceptibility profile, clonal pattern, and genomic species identification were also evaluated. Based on the six complete genomes ofA. baumannii, the PBP genes were identified, and primers were designed for each gene. The nucleotide sequences of the genes identified that encode PBPs and the corresponding amino acid sequences were compared with those of ATCC 17978. Seven PBP genes and one monofunctional transglycosylase (MGT) gene were identified in the six genomes, encoding (i) four high-molecular-mass proteins (two of class A, PBP1a [ponA] and PBP1b [mrcB], and two of class B, PBP2 [pbpAormrdA] and PBP3 [ftsI]), (ii) three low-molecular-mass proteins (two of type 5, PBP5/6 [dacC] and PBP6b [dacD], and one of type 7 (PBP7/8 [pbpG]), and (iii) a monofunctional enzyme (MtgA [mtgA]). Hot spot mutation regions were observed, although most of the allelic changes found translated into silent mutations. The amino acid consensus sequences corresponding to the PBP genes in the genomes and the clinical isolates were highly conserved. The changes found in amino acid sequences were associated with concrete clonal patterns but were not directly related to susceptibility or resistance to β-lactams. An insertion sequence disrupting the gene encoding PBP6b was identified in an endemic carbapenem-resistant clone in one of the participant hospitals.
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Berti, Andrew D., Erin Theisen, John-Demian Sauer та ін. "Penicillin Binding Protein 1 Is Important in the Compensatory Response of Staphylococcus aureus to Daptomycin-Induced Membrane Damage and Is a Potential Target for β-Lactam–Daptomycin Synergy". Antimicrobial Agents and Chemotherapy 60, № 1 (2015): 451–58. http://dx.doi.org/10.1128/aac.02071-15.

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ABSTRACTThe activity of daptomycin (DAP) against methicillin-resistantStaphylococcus aureus(MRSA) is enhanced in the presence of β-lactam antibiotics. This effect is more pronounced with β-lactam antibiotics that exhibit avid binding to penicillin binding protein 1 (PBP1). Here, we present evidence that PBP1 has a significant role in responding to DAP-induced stress on the cell. Expression of thepbpAtranscript, encoding PBP1, was specifically induced by DAP exposure whereas expression ofpbpB,pbpC, andpbpD, encoding PBP2, PBP3, and PBP4, respectively, remained unchanged. Using a MRSA COL strain withpbpAunder an inducible promoter, increasedpbpAtranscription was accompanied by reduced susceptibility to, and killing by, DAPin vitro. Exposure to β-lactams that preferentially inactivate PBP1 was not associated with increased DAP binding, suggesting that synergy in the setting of anti-PBP1 pharmacotherapy results from increased DAP potency on a per-molecule basis. Combination exposure in anin vitropharmacokinetic/pharmacodynamic model system with β-lactams that preferentially inactivate PBP1 (DAP-meropenem [MEM] or DAP-imipenem [IPM]) resulted in more-rapid killing than did combination exposure with DAP-nafcillin (NAF) (nonselective), DAP-ceftriaxone (CRO) or DAP-cefotaxime (CTX) (PBP2 selective), DAP-cefaclor (CEC) (PBP3 selective), or DAP-cefoxitin (FOX) (PBP4 selective). Compared to β-lactams with poor PBP1 binding specificity, exposure ofS. aureusto DAP plus PBP1-selective β-lactams resulted in an increased frequency of septation and cell wall abnormalities. These data suggest that PBP1 activity may contribute to survival during DAP-induced metabolic stress. Therefore, targeted inactivation of PBP1 may enhance the antimicrobial efficiency of DAP, supporting the use of DAP–β-lactam combination therapy for serious MRSA infections, particularly when the β-lactam undermines the PBP1-mediated compensatory response.
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Łęski, Tomasz A., and Alexander Tomasz. "Role of Penicillin-Binding Protein 2 (PBP2) in the Antibiotic Susceptibility and Cell Wall Cross-Linking of Staphylococcus aureus: Evidence for the Cooperative Functioning of PBP2, PBP4, and PBP2A." Journal of Bacteriology 187, no. 5 (2005): 1815–24. http://dx.doi.org/10.1128/jb.187.5.1815-1824.2005.

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ABSTRACT Ceftizoxime, a beta-lactam antibiotic with high selective affinity for penicillin-binding protein 2 (PBP2) of Staphylococcus aureus, was used to select a spontaneous resistant mutant of S. aureus strain 27s. The stable resistant mutant ZOX3 had an increased ceftizoxime MIC and a decreased affinity of its PBP2 for ceftizoxime and produced peptidoglycan in which the proportion of highly cross-linked muropeptides was reduced. The pbpB gene of ZOX3 carried a single C-to-T nucleotide substitution at nucleotide 1373, causing replacement of a proline with a leucine at amino acid residue 458 of the transpeptidase domain of the protein, close to the SFN conserved motif. Experimental proof that this point mutation was responsible for the drug-resistant phenotype, and also for the decreased PBP2 affinity and reduced cell wall cross-linking, was provided by allelic replacement experiments and site-directed mutagenesis. Disruption of pbpD, the structural gene of PBP4, in either the parental strain or the mutant caused a large decrease in the highly cross-linked muropeptide components of the cell wall and in the mutant caused a massive accumulation of muropeptide monomers as well. Disruption of pbpD also caused increased sensitivity to ceftizoxime in both the parental cells and the ZOX3 mutant, while introduction of the plasmid-borne mecA gene, the genetic determinant of the beta-lactam resistance protein PBP2A, had the opposite effects. The findings provide evidence for the cooperative functioning of two native S. aureus transpeptidases (PBP2 and PBP4) and an acquired transpeptidase (PBP2A) in staphylococcal cell wall biosynthesis and susceptibility to antimicrobial agents.
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Dissertations / Theses on the topic "PBpa"

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Braxton, Courtney N. "The progress on mapping ubiquitin signaling using photocrosslinking mono and di-ubiquitin probes and other ubiquitin moieties." VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5382.

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Ubiquitin (Ub) is a small, 76 amino acid, and post-translational modification (PTM) protein in eukaryotes. Modification of a substrate protein via the covalent attachment of the C-terminal glycine of Ub to the ε-amino group of lysine residues in a substrate is termed ubiquitination. Unlike, other PTM proteins, Ub can form polyUb chains at one or more of its seven lysine residues. (K6, K11, K27, K29, K33, K48, and K68). The consequence of these different polymerization sites is altered biological response with different polyUb linkages conferring different fates to target proteins. Unfortunately, the study of these chains have been limited by the inability to generate homogeneous polyUbs chains linked at known lysine residues. Furthermore, a three step enzymatic cascade consisting of activating-enzymes (E1s), conjugating enzymes (E2s), and ligase enzymes (E3s) tightly controls this modification. In response, our laboratory has developed a system that creates polyUb chains through bacterial expression and "synthetic" building blocks. Now, the main questions are what do these chains interact with in the cell and how do these interactions mediate biological responses? In an attempt to answer these questions, this dissertation looks at different molecular techniques created to capture the transient interactions of monoUb and diUb probes with Ub substrates, such as, ubiquitin binding domains (UBDs) and conjugating E2 enzymes. One molecular technique focuses on the use of incorporating a genetically encoded, photo-crosslinker, p-Benzoyl-L-phenylalanine (pBpa) into diUb probes to capture their interaction with UBDs. This sets the foundation for understanding Ub’s cellular signaling recognition of UBDs. Another technique is creating diUb probes that contain lysine derivatives, Nε-L-Thiaprolyl-L-lysine (ThzK) or Nε-L-Cysteinyl-L-lysine (CysK), and can form a disulfide bonds with E2 enzymes to capture their complex, opening an opportunity to understand mechanistically the role E2 enzymes have with polyUb chain formation. Herein, these techniques are established to help unravel the complexity of Ub signaling.
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Wei, Yuping. "Characterization of two Bacillus subtilis penicillin-binding protein-coding genes, ykuA (pbpH) and yrrR (pbpI)." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/34900.

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<p> Penicillin-binding proteins (PBPs) are required in the synthesis of the cell wall of bacteria. In Bacillus subtilis, PBPs play important roles in the life cycle, including both vegetative growth and sporulation, and contribute to the formation of the different structures of vegetative cell wall and spore cortex. The B. subtilis genome sequencing project revealed there were two uncharacterized genes, ykuA and yrrR, with extensive sequence similarity to class B PBPs. These two genes are renamed and referred to henceforth as pbpH and pbpI, respectively. </p><p>A sequence alignment of the predicted product of pbpH against the microbial protein database demonstrated that the most similar protein in B. subtilis is PBP2A and in E. coli is PBP2. This suggested that PbpH belongs to a group of the genes required for maintaining the rod shape of the cell. Study of a pbpH-lacZ fusion showed that pbpH was expressed weakly during vegetative growth and the expression reached the highest level at the transition from exponential phase to stationary phase. The combination of a pbpA deletion and the pbpH deletion was lethal and double mutant strains lacking pbpH and pbpC or pbpI (also named yrrR) were viable. The viable mutants were indistinguishable from the wild-type except that the vegetative PG of the pbpC pbpH strain had a slightly slightly lower amount of disaccharide tetrapeptide with 1 amidation and higher amount of disaccharide tripeptide tetrapeptide with 2 amidations when compared to others strains. This suggests that PbpC (PBP3) is involved in vegetative PG synthesis but only affects the PG structure with a very low efficiency. </p><p>A pbpA pbpH double mutant containing a xylose-regulated pbpH gene inserted into the chromosome at the amyE locus was constructed. Depletion of PbpH resulted in an arrest in cell growth and a dramatic morphological change in both vegetative cells and outgrowing spores. Vegetative cells lacking pbpA and pbpH expression swelled and cell elongation was arrested, leading to the formation of pleiomorphic spherical cells and eventual lysis. In these cells, cell septations were randomly localized, cell walls and septa were thicker than those seen in wild type cells, and the average cell width and volume were larger than those of cells expressing pbpA or pbpH. The vegetative PG had an increased abundance of one unidentified muropeptide. Spores produced by the pbpA pbpH double mutant were able to initiate germination but the transition of the oval-shaped spores to rod-shape cells was blocked. The outgrowing cells were spherical, gradually enlarged, and eventually lysed. Outgrowth of these spores in the presence of xylose led to the formation of helical cells. Thus, PbpH is apparently required for maintenance of cell shape, specifically for cell elongation. PbpH and PBP2a play a redundant role homologous to that of PBP2 in E. coli. </p><p>A sequence alignment of the predicted product of pbpI against the microbial protein database demonstrated that the most similar protein in B. subtilis is SpoVD and in E. coli is PBP3. This suggested that PbpI belongs to the group of the genes required for synthesis of the spore or septum PG. PbpI was identified using radio-labeled penicillin and found to run underneath PBP4 on SDS-PAGE. PbpI is therefore renamed PBP4b. Study of a pbpI-lacZ fusion showed that pbpI was expressed predominantly during early sporulation. A putative sigma F recognition site is present in the region upstream of pbpI and studies using mutant strains lacking sporulation-specific sigma factors demonstrated that the expression of pbpI is mainly dependent on sigma factor F. A pbpI single mutant, a pbpI pbpG double mutant, and a pbpI pbpF double mutant were indistinguishable from the wild-type. The sporulation defect of a pbpI pbpF pbpG triple mutant was indistinguishable from that of a pbpF pbpG double mutant. Structure parameters of the forespore PG in a pbpI spoVD strain are similar to that of a spoVD strain. These results indicate that PBP4b plays a unknown redundant role. </p><br>Master of Science
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3

Paulin, S. "Impact of epicatechin gallate on the structural integrity of the PBP2/PBP2a complex in methicillin resistant Staphylococcus aureus." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1434251/.

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Introduction: The selective pressure imposed by the misuse and overuse of antibiotics has led to the emergence and dissemination of methicillin resistant Staphylococcus aureus (MRSA), forcing a re-evaluation of therapeutic approaches to the treatment of MRSA infections. Epicatechin gallate (ECg), a constituent of the tea plant Camellia sinensis, has the capacity to abrogate the resistance of MRSA to β-lactam antibiotics and may be useful as an adjunct to conventional chemotherapy. Current evidence suggests that ECg sensitises resistant strains to β-lactam agents by disruption of the penicillin binding protein (PBP) complex PBP2/PBP2a at the septal site of cell division following its intercalation into the cytoplasmic membrane (CM) bilayer. Methods: Styrene maleic acid lipid co-polymer (SMALP) was used to solubilise and extract PBP2/PBP2a membrane complexes from the CM of EMRSA-16 and ECg-exposed cells. Cell walls were partially digested and membrane proteins excised and solubilised with hydrolysed styrene maleic acid (SMA). SMALP particles were visualised by TEM and size distribution determined by dynamic light scattering. Membrane protein complexes were cross-linked within SMALPs, protein complexes recovered by co-immunoprecipitation and the constituents determined by Western blotting and flow cytometry. Results: PBP2/PBP2a complexes were identified in both ECg-exposed and control EMRSA-16 cells when SMALPs were pulled down with anti-PBP2 and anti-PBP2a antibodies. Fewer complexes were recovered from ECg exposed cells. Co-immunoprecipitation of SMALPs with antibody against the division scaffold protein FtsZ led to the identification of FtsZ/PBP2/PBP2a complexes. ECg displaced PBP2a from this complex. The PBP2/PBP4 complex was also identified, however there was no difference observed following ECg exposure. Conclusion: Intercalation of ECg into the MRSA phospholipid palisade led to partial disruption of PBP2a from PBP2/PBP2a and FtsZ/PBP2/PBP2a complexes. The data suggest that ECg-mediated conversion of MRSA to β-lactam susceptibility may in part be related to loss of functional integrity of the cellular replication machinery. The therapeutic approach with the use of antibiotic resistance modifying agent, such as ECg, in combination with a previously ineffective β-lactam antibiotic, presents a novel therapy to combat antibiotic resistance in MRSA.
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4

Stöckl, Stefanie. "Modellierung PBPK-relevanter Verteilungskoeffizienten organischer Stoffe." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2014. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-131508.

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Drei Verteilungskoeffizienten, die für physiologie-basierte Pharmakokinetik (PBPK)-Modelle relevant sind, wurden mit verschiedenen Ansätzen modelliert. Für den Blut/Luft-Verteilungskoeffizienten wurde ein auf linearen Solvatations-Energie-Beziehungen (LSER) beruhendes Literaturmodell angewendet und diskutiert. Mit einer schematischen Aufteilung des Blutkompartiments in Wasser und einen organischen Teil wurde der Blut/Luft-Verteilungskoeffizient mit einer linearen Regression von anderen Verteilungskoeffizienten vorhergesagt. Zusätzlich wurde ein Fragmentmodell entwickelt. Der Fett/Luft-Verteilungskoeffizient wurde mit dem LSER-Ansatz und mit anderen Verteilungskoeffizienten modelliert. Der Koeffizient Fett/Blut wurde aus den ersten beiden errechnet. Da der inverse dimensionslose Henry-Koeffizient Wasser/Luft-Verteilungskoeffizient bei der Blut/Luft-Modellierung zum Einsatz kommt und dieser aus dem Dampfdruck und der Wasserlöslichkeit gewonnen werden kann, wurde der Dampfdruck ebenfalls modelliert.
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5

Gómez, Serrano Amalia. "Studies on pbp2 of Staphylococcus aureus." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624442.

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Bøe, Andreas Gagnat. "Degradation and Stability of PBCA and POCA Nanoparticles." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for fysikk, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-22417.

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Nanoparticles represent promising carriers for controlled drug delivery. In this project threedifferent intruments: Zetasizer, Nanosight and Gas Chromatography, have been used to detect and analyse degradation of monodisperse poly butylcyanoacrylate (PBCA) and polyoctylcyanoacrylate (POCA) nanoparticles with a mean size diameter of 145 and 155 nm,respectively. It was found that the Nanosight and Gas Chromatography are valuable instrumentsfor detecting and analysing degradation, whereas the Zetasizer turned out to giveunreliable results because of increasing polydispersity in the samples. PBCA and POCAparticles were tested in two different setups. One including a dialysis setup in room temperature,in which the solvent was regularly exchanged. The other consisted of reagent bottlesheld in an oven at 37C. In the dialysis method the influence of buffers with pH 4.0, pH5.5 and pH 7.4 were tested. In the reagent bottles different mediums were tested, like cellmedium, blood serum and buffer pH 7.4 with and without the enzyme esterase. From theseexperiments it became clear that PBCA particles degraded significantly faster than POCAparticles in all tested mediums. Degradation of PBCA particles were also strongly affectedby the pH. At pH 4.0 there was little (10%) or no degradation still after 30 days. The concentration of PBCA particles in pH 7.4 decayed as a 1/x -function, in which 53\% of the PBCA particles in buffer pH 7.4 have been degraded after 8.5 hours.The degradation-rate for PBCA and POCA in blood serum was approximately similar as in buffer pH 7.4, whereas in cell medium it was slightly slower.
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Alsmadi, Mo'tasem Mohamed. "Physiologically based pharmacokinetic (PBPK) model of Ivermectin (IVM)." Diss., University of Iowa, 2014. https://ir.uiowa.edu/etd/5906.

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Purpose: Ivermectin (IVM) is a lipophilic BCS-II compound (molecular weight=875 g/mole, LogP=3.22, intrinsic solubility=700 ug/L). IVM is used as antiparasitic drug in both humans and animals. IVM is known to have a half-life of 12-56 hours in humans. Strongyloidiasis is a chronic parasitic infection of humans caused by Strongyloides stercoralis, with an estimated 30-100 million people infected worldwide. Infection may be severe and even life-threatening in cases of immunodeficiency. Patients with disseminated strongyloidiasis are usually bedridden hospitalized patients that show symptoms such as paralytic ileus and reduced plasma albumin and cholesterol. Oral IVM is the only FDA-approved treatment but may not be effective in patients with disseminated disease. Veterinary subcutaneous formulations have been used in severe infections. We hypothesized that IVM PK in patients with disseminated strongyloidiasis can be predicted using PBPK model originally built and refined in healthy human and animal species. This hypothesis was tested and shown to be valid. Methods:A systematic method was used to build and refine different parts of the PBPK model. The process involved construction of models, parameterization of these models, evaluation of the effect of uncertainty in model parameters on model prediction via local and global sensitivity analyses and finally, refinement of model predictions. Two disposition models that differ in the rate limiting step in drug distribution were constructed and include perfusion-limited and permeability-limited distribution models. The ability of each model to predict IVM disposition was evaluated using plasma PK data in rat after intra-arterial dosing and in dog after intravenous bolus dosing. Then the disposition model was scaled to humans and an oral input model was constructed as a modification on the well-known ACAT model. The oral input model was coupled with the disposition model and used to predict IVM plasma concentration-time profile in healthy fasted human subject after oral dosing. Two subcutaneous (SQ) input models were constructed and used to evaluate the effect of IVM precipitation at the injection site. Plasma PK data in dog after SQ dosing was used to refine the constructed SQ input models. The refined disposition, oral input and SQ input physiologically-based models were used to predict IVM PK in patients with disseminated strongyloidiasis after a complex dosing regimen. The physiological parameters of the model were modified to account for the effect of the disease-induced pathophysiological changes on the body physiology and hence on the drug PK. Plasma PK data from hospitalized subjects with disseminated strongylidiasis was used in this part. Results and conclusions:The disposition model with assumption of permeability-limited distribution was more capable of describing IVM disposition in rat after intra-arterial dosing compared to when perfusion-limited distribution was assumed. The model predicted that hepatic clearance is the most impactful parameter on model-predicted plasma concentration of the drug. Also, IVM was shown to have low hepatic extraction ratio along with high binding in plasma and large volume of distribution, which collectively may explain the long half-life in the plasma of 63 hours in rat after intra-arterial dosing. The oral input model predicted that the oral input is limited by drug dissolution in the GI lumen and that a very small fraction of oral tablet dose (0.03) is available in the systemic circulation in healthy fasted human subjects. Both of the studied SQ input models predicted that majority of IVM absorption after SQ dosing is via the lymphatic route and that drug precipitation at the injection site can further slowdown the drug absorption after SQ administration. The PBPK model was able achieve the main goal of this research which is to predict IVM pharmacokinetics in patients with disseminated strongyloidiasis after a complex dosing regimen of multiple oral and SQ dosing. This was achieved by modifying the most impactful physiological parameters of the model affected by the disease state and that are related to drug binding in the plasma (fraction unbound), the GI motility (gastric emptying rate) and the lymphatic flow rate. Based on our analysis, we recommend measurement of plasma IVM concentrations early after initiation of therapy to exclude treatment failure due to reduced oral and/or SQ absorption. Also, we recommend measurement of plasma lipoprotein levels and their composition in these patients to differentiate between low total plasma concentrations due to low binding plasma as opposed to low drug input. Finally, interventional procedures that enhance lymphatic flow rate to site of SQ injection are recommended to enhance SQ absorption.
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Gulhan, Doga C. (Doga Can). "Properties of dijets in pp, pPb and PbPb collisions." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104504.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Physics, 2016.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (pages 217-232).<br>Two dijet measurements, one using 35 pb-¹ pPb data at [square root]sNN- 5.02 TeV, and another with 166 [mu]b-¹ PbPb and 5.3 pb-¹ pp data at [square root]sNN = 2.76 TeV collected with CMS detector at the LHC, are presented. In pPb collisions, the dijet PT ratios, azimuthal angle differences and pseudorapidity distributions are measured and compared to PYTHIA and PYTHIA+HIJING simulations as well as NLO QCD predictions for the latter observable. No significant signs of final state interactions, such as a decrease in the mean dijet PT ratios or a broadening in the correlation of the dijets in azimuthal angle, with increasing forward activity, are observed. The dijet pseudorapidity distributions are also measured, and are sensitive to nuclear PDFs for x values of 0.001 - 0.5. Selections on event activity are found to yield unexpected centrality biases on dijet pseudorapidity distributions, which aided the interpretation of similar biases seen in inclusive jet measurements by ATLAS. In PbPb collisions, a detailed scan of charged particle distributions in correlation with the dijet system is carried out. The PT projection of charged particles on the dijet axis is measured at different distances of [delta] = [mathematical formula ...] 2 with respect to the leading and subleading jet axes. In this way, the spectra and angular distribution of the additional particles, which recover the overall event balance in dijet events with enhanced PT asymmetry in PbPb compared to pp collisions, are obtained up to [delta] = 1.8 in steps of 0.2. A significant excess of low PT particles associated with a subleading jet at large [delta] values is observed, and this excess is shown to get larger for dijet events with PT asymmetry. The scan is carried out for variety of anti-kT R parameters, which provides a way of varying jet width and fragmentation. Medium response to jet quenching at wide angles for jets with different fragmentation is studied. Only an insignificant increase of the magnitude of low PT particle excess at large angles, but a significant increase in the modification of the balance distribution close to the jet axes is observed by increasing R.<br>by Doga C. Gulhan.<br>Ph. D.
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Abass, Abdul-Kariem. "Electrical and optical studies of lead phthalocynanine (PbPc) thin films." Thesis, Lancaster University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239800.

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Mororó, Janio da Silva. "Estudo de marcação do anticorpo monoclonal anti-PBP2a com 99mTc." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-06032013-151412/.

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Staphylococcus aureus é um dos principais microorganismos causadores de infecção em humanos, podendo causar inclusive bacteremia e endocardite nos indivíduos infectados. Diversas cepas desta bactéria apresentam resistência a diferentes tipos de antibióticos, dentre eles os antibióticos meticilina e amoxicilina, como no caso da bactéria Staphylococcus aureus resistente à meticilina (MRSA). A Proteína ligadora de Penicilina 2a (PBP2a) é a enzima responsável por conferir resistência para a MRSA aos antibióticos &beta;-lactâmicos, sendo uma molécula promissora para terapia com AcM. No entanto, além das terapias os métodos de diagnóstico também são ineficientes, pois atualmente o diagnóstico leva vários dias para produzir um resultado confiável. O objetivo deste trabalho foi desenvolver um radiofármaco utilizando o AcM anti-PBP2a, desenvolvido em Bio-Manguinhos/FioCruz, marcado com 99mTc, para identificação in situ do foco infeccioso causado por MRSA. Neste trabalho, incialmente o AcM anti-PBP2a foi reduzido com o agente redutor 2-mercaptoetanol (2-ME), para gerar grupos sulfidrilas (- SH). Logo após foram utilizados dois diferentes métodos da Marcação Direta: o Método 1, utilizando o reagente tartarato e o ácido gentísico, que atuam como agente transquelante e estabilizador, respectivamente; e o Método 2, utilizando um kit comercial de MDP, no qual o MDP atua como agente transquelante. Após a marcação do anticorpo, o radiofármaco foi submetido a ensaios de avaliação funcional, utilizando os métodos de eletroforese em gel SDS-PAGE não redutor; Immunoblotting; ELISA e o Ensaio de Neutralização in vitro. Como resultado foi visto que a quantidade média de grupos sulfidrilas produzida por AcM foi considerada satisfatória, cerca de 5 grupos SH por IgG, utilizando para isto a relação molar de 6.500:1 de 2-ME:AcM. O Método 2 foi o método que obteve melhor rendimento de marcação, com 73,5%, apresentando boa estabilidade depois de 2 horas (73,2%). A melhor formulação utilizada foi a seguinte: 0,5 mg de AcM anti-PBP2a; 10 &mu;L do kit do MDP, depois de ser resuspendido com 5 mL de solução salina; e 75,48 MBq (2,04 mCi) de 99mTc, a reação ocorrendo em 15 minutos. Os Ensaios de Avaliação Funcional demonstraram que o AcM manteve a especificidade e afinidade de ligação à PBP2a.<br>Staphylococcus aureus is a major cause of life-threatening infections such as bacteremia and endocarditis. Unfortunately, many strains of this bacterial species have become resistant to certain antibiotics, including methicillin and amoxicillin. These strains are known as methicillin-resistant S. aureus (MRSA). The penicillin binding protein 2a (PBP2a) is the enzyme responsible for conferring resistance &beta;-lactams antibiotics for MRSA, being one promising molecule for therapy with mAb. However, besides the therapy, the methods of diagnosis are also inefficient because the diagnosis currently takes several days to produce a reliable result. Taking into account, the objective of this research was radiolabeling one anti-PBP2a mAb developed by Bio-Manguinhos/FioCruz-RJ, utilizing 99mTc, for in situ diagnostic of the infectious caused by MRSA. First, anti-PBP2a mAb was reduced utilizing 2-mecaptoethanol (2-ME) for generate sulphydryl groups (-SH) and after to be labeled with 99mTc. In this work, were utilized two techniques of direct method: Method 1, using tartrate and gentisic acid reagents, acting like transchelant and stabilizer agents, respectively; and Method 2, using one commercial kit of MDP. Besides the radiolabeling, the mAb reduced and mAb labeled with 99mTc were submitted to immunoreactivity analysis, with SDS-PAGE non-reducing, Immunoblotting, ELISA and neutralization assay in vitro methods. The quantity produced of sulphydryl groups by mAb was satisfactory, approximately 5 per mAb, utilizing 6.500:1 of 2-ME:mAb molar ratio. The better labeling method was Method 2, with labeling yield of 73.5%, and showed a good stability after 2 hours (73.2%). The better formulation was: 0.5 mg of mAb anti- PBP2a, 10 &mu;L of MDP kit, after resuspended with 5 mL of saline, and 75.48 MBq (2.04 mCi) of 99mTc, reacting by 15 minutes. The labeled mAb maintained the immunoreactivity, utilizing immunologic and in vitro experiments.
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Books on the topic "PBpa"

1

Peters, Sheila Annie. Physiologically-Based Pharmacokinetic (PBPK) Modeling and Simulations. John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118140291.

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State agency UI program and budget plans (PBP) planning and reporting guidelines: PBP handbook. U.S. Dept. of Labor, Employment and Training Administration, 1996.

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Administration, United States Employment and Training. State agency UI program and budget plans (PBP) planning and reporting guidelines: PBP handbook. U.S. Dept. of Labor, Employment and Training Administration, 1996.

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United States. Office of the Deputy Under Secretary of Defense for Acquisition Reform. Guidebook for performance-based services acquisition (PBSA) in the Department of Defense. Defense Acquisition University Press, 2001.

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Knaak, James B., Charles Timchalk, and Rogelio Tornero-Velez. Parameters for pesticide QSAR and PBPK/PD models for human risk assessment. Edited by American Chemical Society and American Chemical Society. Division of Agrochemicals. American Chemical Society, 2012.

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Knaak, James B., Charles Timchalk, and Rogelio Tornero-Velez, eds. Parameters for Pesticide QSAR and PBPK/PD Models for Human Risk Assessment. American Chemical Society, 2012. http://dx.doi.org/10.1021/bk-2012-1099.

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Giordani, Víctor. Las 5 leyes para lograrlo todo: Con técnicas de PBA. Panorama, 2008.

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Institute, Pennsylvania Bar. PBA pro bono seminar: Reaching out to the neediest among us. Pennsylvania Bar Institute, 2011.

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Physiologically based pharmacokinetic (PBPK) modeling and simulations: Principles, methods, and applications in the pharmaceutical industry. Wiley, 2011.

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Nadarajah, Jeya Thirumagal. A role for penicillin-binding protein 2 (PBP2) in conferring the borderline oxacillin-resistant phenotype of Staphylococcus aureus. National Library of Canada, 2002.

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Book chapters on the topic "PBpa"

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Gooch, Jan W. "PBMA." In Encyclopedic Dictionary of Polymers. Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-6247-8_8478.

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Steiner, G., and C. Zimmerer. "(butyl methacrylate) (PBMA)." In Polymer Solids and Polymer Melts – Definitions and Physical Properties I. Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-32072-9_55.

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Löding, Christof, and Anton Pirogov. "Ambiguity, Weakness, and Regularity in Probabilistic Büchi Automata." In Lecture Notes in Computer Science. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-45231-5_27.

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AbstractProbabilistic Büchi automata are a natural generalization of PFA to infinite words, but have been studied in-depth only rather recently and many interesting questions are still open. PBA are known to accept, in general, a class of languages that goes beyond the regular languages. In this work we extend the known classes of restricted PBA which are still regular, strongly relying on notions concerning ambiguity in classical $$\omega $$ ω -automata. Furthermore, we investigate the expressivity of the not yet considered but natural class of weak PBA, and we also show that the regularity problem for weak PBA is undecidable.
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Ibarra, Manuel, Alejandra Schiavo, and Lawrence J. Lesko. "Physiologically Based Pharmacokinetic (PBPK) Modeling: Software." In The ADME Encyclopedia. Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-51519-5_166-1.

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Overbeek, Roy, Jörg Endrullis, and Aloïs Rosset. "Graph Rewriting and Relabeling with PBPO$$^{+}$$." In Graph Transformation. Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-78946-6_4.

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Steiner, G., and C. Zimmerer. "Poly(1,4-butylene adipate) (PBA)." In Polymer Solids and Polymer Melts – Definitions and Physical Properties I. Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-32072-9_81.

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Ibarra, Manuel, Alejandra Schiavo, and Lawrence J. Lesko. "Physiologically Based Pharmacokinetic (PBPK) Modeling: Model Structure." In The ADME Encyclopedia. Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-51519-5_167-1.

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Pal, Shilpa, and Anindya S. Ghosh. "PBP Isolation and DD-Carboxypeptidase Assay." In Methods in Molecular Biology. Springer New York, 2019. http://dx.doi.org/10.1007/978-1-4939-9118-1_20.

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Bellama, J. M. "With Gege, Snsn and Pbpb Bonds (Excluding Tellurium)." In Inorganic Reactions and Methods. John Wiley & Sons, Inc., 2007. http://dx.doi.org/10.1002/9780470145197.ch144.

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Bouloc, Philippe, Daniel Vinella, Danièle Joseleau-Petit, and Richard D’Ari. "Does PBP2 Regulate Cell Division in E. coli?" In Bacterial Growth and Lysis. Springer US, 1993. http://dx.doi.org/10.1007/978-1-4757-9359-8_21.

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Conference papers on the topic "PBpa"

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Feng, Xizhou, Kirk W. Cameron, and Duncan A. Buell. "Biology---PBPI." In the 2006 ACM/IEEE conference. ACM Press, 2006. http://dx.doi.org/10.1145/1188455.1188535.

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Nurmi, Sami T., Janne J. Sundelin, Eero O. Ristolainen, and Toivo K. Lepisto¨. "The Effect of Multiple Reflow Times on Lead-Free Solder Joint Microstructure." In ASME 2003 International Electronic Packaging Technical Conference and Exhibition. ASMEDC, 2003. http://dx.doi.org/10.1115/ipack2003-35150.

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As environmental issues are raising more interest and are becoming crucial factors in all parts of the world, more and more environmental-friendly electronics products are emerging. Usually this means the introduction of products with lead-free solders. However, the reliability of lead-free solders is still a serious concern despite the vast research done in this field. This paper will describe the interconnect reliability of three kinds of solder joints respectively prepared with lead-free solder paste and lead-free PBGA components, lead-free solder paste and tin-lead-silver PBGA components, and tin-lead solder paste and tin-lead-silver PBGA components. Lead-free and tin-lead solders were composed of eutectic tin-silver-copper and tin-lead, respectively. In addition, the study also presents the effect of multiple reflow times. The study focuses on the microstructures of different assemblies. The particular interest is on the assemblies soldered with lead-free solder paste and tin-lead-silver PBGA components, since the SnPbAg solder on the bumps of the PBGA components were exposed to the reflow profile meant for the lead-free SnAgCu solder. Thus, these SnPbAg solder bumps were in the molten state almost twice as long as the rest of the solders. This had a notable effect on the reliability of these solder joints as we will be showing later in this paper. The test boards were temperature-cycled for 2500 cycles between −40 and +125°C (a 30-minute cycle). PBGA solder joint failures were monitored with a real time monitoring system. Optical and scanning electron microscopy was used to inspect the broken solder joints and their microstructure. The results of tests indicate that the number of reflow times can significantly affect the lifetime of PBGA solder joints. The most notable changes can be seen in the solder joints made with tin-lead-silver PBGA components and tin-silver-copper solder paste soldered with a lead-free reflow profile. The general trend was that the reliability of the solder joints increased in proportion to the number of reflow times. Mainly two factors are believed to have the major effect on the reliability of PBGA solder joints, voids, and microstructural changes in solder.
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Nickerson, Mark D., and Chandrakant S. Desai. "Design and Reliability in Electronic Packaging Including Power Temperature Cycling and Vibration Effects." In ASME 2003 International Electronic Packaging Technical Conference and Exhibition. ASMEDC, 2003. http://dx.doi.org/10.1115/ipack2003-35353.

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Thermomechanical, power temperature cycling (PTC) and vibration analyses were performed on a 313 staggered pin PBGA package using plastic and viscoplastic disturbed-state damage models. An accelerated finite element failure analysis was performed using a newly developed procedure. Validations were performed using published PBGA test data. The disturbed state concept was used to model the disturbance (damage) accumulated in PBGA solder joints subjected to thermal cycling (PTC and TCT), vibration, and vibration coupled with three distinct temperatures. 2D FEA plastic and viscoplastic models were created based on a diagonal “slice” of the PBGA. This allowed the most critical solder balls (under the die and furthest DNP) to be analyzed in the same model. The thermal cycling results indicate that the solder balls under the die are the most likely to fail. The vibration results indicate the solder balls furthest from the package center are most likely to fail. The vibration results, coupled with distinct isothermal temperatures, indicate that as temperature increases, the cycles to failure decreases.
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do Vale Hipolito Cavalheiro, Joao Pedro, Nuno Miguel Matos Pires, and Tao Dong. "MM-PBSA: Challenges and opportunities." In 2017 10th International Congress on Image and Signal Processing, BioMedical Engineering and Informatics (CISP-BMEI). IEEE, 2017. http://dx.doi.org/10.1109/cisp-bmei.2017.8302303.

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Wang, Jinsu, Sharad Mehrotra, and Nalini Venkatasubramanian. "PBCA - Prediction Based Channel Allocation." In IEEE GLOBECOM 2007-2007 IEEE Global Telecommunications Conference. IEEE, 2007. http://dx.doi.org/10.1109/glocom.2007.911.

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Lau, John, Ricky Lee, Walter Dauksher, Dongkai Shangguan, Fubin Song, and Dennis Lau. "A Systematic Approach for Determining the Thermal Fatigue-Life of Plastic Ball Grid Array (PBGA) Lead-Free Solder Joints." In ASME 2005 Pacific Rim Technical Conference and Exhibition on Integration and Packaging of MEMS, NEMS, and Electronic Systems collocated with the ASME 2005 Heat Transfer Summer Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/ipack2005-73364.

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Reliability of plastic ball grid array (PBGA) SnAgCu lead-free solder joints is investigated. Emphasis is placed on the design for reliability (DFR) of lead-free solder joints. In particular, the thermal-fatigue life of the lead-free solder joints of a PBGA package assembly is predicted and compared with thermal cycling test results.
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Widuch, Kaja. "‘I AM NOT A MONSTER': THE LINGUISTIC STIGMA OF BORDERLINE PERSONALITY DISORDER." In International Psychological Applications Conference and Trends. inScience Press, 2021. http://dx.doi.org/10.36315/2021inpact085.

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"Borderline Personality Disorder is arguably the most distressing disorder amongst the DSM diagnoses for all involved. Although psychiatric labelling can be validating it is often stigmatising. Due to the nature of BPD, people living with the disorder (PBPD) tend to be marginalized and discriminated against. A quick and random review of the World Wide Web (including a selection of popular social media platforms) reveals a common linguistic theme in describing BPD. PBPD are ‘toxic’, ‘difficult’ and ‘manipulative. Other labels, more diagnostically - oriented see PBPD as the ‘PDs’ or ‘the borderlines’. These also carry negative connotations of the inner and outer groups - ‘us’ vs ‘them’. Given the nature of the labels, recovery for PBPD is often dubious. One might think - ‘I am a monster anyway’, a classic example of cognitive dissonance. The language used in clinical practice as well as out of it is a powerful weapon. Some might poetically describe BPD as a lethal cocktail of blended psychopathologies with the ingredients including chronic suicidality, abandonment and intermittent lucidity to name a few. Of note, externalising such pathologies in an adaptive way is almost a fantasy for the therapy team. A more user friendly descriptive diagnosis is ‘difficulty in emotion regulation’. However, probably the most accurate ‘label’ of BPD for PBPD is ‘living in acute pain’. The current climate and the uncertainty surrounded the ongoing COVID-19 pandemic has meant a significantly increased risk not only in symptoms remission but also in the increase in cyber-bullying and suicidality rate. The pandemic has also put a halt to the Participant and Public Involvement in the evidence based practice. Linguistic shift in reducing stigma is essential and of immediate need."
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Adams, Rickie M., Andrew Glovatsky, Theresa Lindley, John L. Evans, and Andrew Mawer. "PBGA Reliability Study for Automotive Applications." In International Congress & Exposition. SAE International, 1998. http://dx.doi.org/10.4271/980341.

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De Groot, J. S., C. Deeney, T. W. L. Sanford, et al. "High velocity implosions on PBFA Z." In DENSE Z-PINCHES. ASCE, 1997. http://dx.doi.org/10.1063/1.53817.

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Pantoja, S., V. Parro, J. Nestler, et al. "Nanophotonic biosensor for space exploration (PBSA instrument)." In International Conference on Space Optics 2014, edited by Bruno Cugny, Zoran Sodnik, and Nikos Karafolas. SPIE, 2017. http://dx.doi.org/10.1117/12.2304119.

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Reports on the topic "PBpa"

1

Fisher, Jeff, Michael Bartlett, and Shonetta D. Gregg. Development of a PBPK Model for JP-8. Defense Technical Information Center, 2006. http://dx.doi.org/10.21236/ada458543.

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Kennedy, Penny S., and Joe T. McClure. Performance-Based Service Acquisition (PBSA) Study and Graduate Level Course Material. Defense Technical Information Center, 2005. http://dx.doi.org/10.21236/ada442999.

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Kojima, M., D. C. Sun, and J. H. Magill. Phase Transitions and Structure Changes in Poly(bis(Phenoxy)Phosphazene) -PBPP. Defense Technical Information Center, 1987. http://dx.doi.org/10.21236/ada198504.

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Baich, M. A. IIT B52 Antifoam Impact Upon PBA Hydrolysis Kinetics. Office of Scientific and Technical Information (OSTI), 2001. http://dx.doi.org/10.2172/781740.

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Cave, William C. The Theoretical Underpinnings of Predictive Battlespace Awareness (PBA). Defense Technical Information Center, 2003. http://dx.doi.org/10.21236/ada418602.

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Bell, R. T., and R. I. Thorpe. PbPb Isochron Age of Uraniferous Phosphorite At the Base of the Menihek Formation, Labrador Trough. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1986. http://dx.doi.org/10.4095/120670.

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Green, T. A., R. W. Stinnett, and R. A. Gerber. Production of lithium positive ions from LiF thin films on the anode in PBFA II. Office of Scientific and Technical Information (OSTI), 1995. http://dx.doi.org/10.2172/116623.

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Avramidis, Christos. An Analysis of the Performance-Based Service Acquisition (PBSA) and Its Applicability to Hellenic Navy Service Acquisition Activities. Defense Technical Information Center, 2012. http://dx.doi.org/10.21236/ada573581.

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9

Payne, S. S. Analysis of the 1989 in-plasma B-dot probe experiments on the Sandia PBFA II plasma opening switch (POS). Office of Scientific and Technical Information (OSTI), 1989. http://dx.doi.org/10.2172/7162135.

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10

Frese, M. H. Dynamics of plasma injection along magnetic field lines in the PBFA II (Particle Beam Fusion Accelerator II) plasma opening switch. Office of Scientific and Technical Information (OSTI), 1989. http://dx.doi.org/10.2172/7161941.

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